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1Version 1.80.1 (2024-08-08)
2===========================
3
4<a id="1.80.1"></a>
5
6- [Fix miscompilation in the jump threading MIR optimization when comparing floats](https://github.com/rust-lang/rust/pull/128271)
7- [Revert changes to the `dead_code` lint from 1.80.0](https://github.com/rust-lang/rust/pull/128618)
8
9Version 1.80.0 (2024-07-25)
10==========================
11
12<a id="1.80-Language"></a>
13
14Language
15--------
16- [Document maximum allocation size](https://github.com/rust-lang/rust/pull/116675/)
17- [Allow zero-byte offsets and ZST read/writes on arbitrary pointers](https://github.com/rust-lang/rust/pull/117329/)
18- [Support C23's variadics without a named parameter](https://github.com/rust-lang/rust/pull/124048/)
19- [Stabilize `exclusive_range_pattern` feature](https://github.com/rust-lang/rust/pull/124459/)
20- [Guarantee layout and ABI of `Result` in some scenarios](https://github.com/rust-lang/rust/pull/124870)
21
22<a id="1.80-Compiler"></a>
23
24Compiler
25--------
26- [Update cc crate to v1.0.97 allowing additional spectre mitigations on MSVC targets](https://github.com/rust-lang/rust/pull/124892/)
27- [Allow field reordering on types marked `repr(packed(1))`](https://github.com/rust-lang/rust/pull/125360/)
28- [Add a lint against never type fallback affecting unsafe code](https://github.com/rust-lang/rust/pull/123939/)
29- [Disallow cast with trailing braced macro in let-else](https://github.com/rust-lang/rust/pull/125049/)
30- [Expand `for_loops_over_fallibles` lint to lint on fallibles behind references.](https://github.com/rust-lang/rust/pull/125156/)
31- [self-contained linker: retry linking without `-fuse-ld=lld` on CCs that don't support it](https://github.com/rust-lang/rust/pull/125417/)
32- [Do not parse CVarArgs (`...`) as a type in trait bounds](https://github.com/rust-lang/rust/pull/125863/)
33- Improvements to LLDB formatting [#124458](https://github.com/rust-lang/rust/pull/124458) [#124500](https://github.com/rust-lang/rust/pull/124500)
34- [For the wasm32-wasip2 target default to PIC and do not use `-fuse-ld=lld`](https://github.com/rust-lang/rust/pull/124858/)
35- [Add x86_64-unknown-linux-none as a tier 3 target](https://github.com/rust-lang/rust/pull/125023/)
36- [Lint on `foo.into_iter()` resolving to `&Box<[T]>: IntoIterator`](https://github.com/rust-lang/rust/pull/124097/)
37
38<a id="1.80-Libraries"></a>
39
40Libraries
41---------
42- [Add `size_of` and `size_of_val` and `align_of` and `align_of_val` to the prelude](https://github.com/rust-lang/rust/pull/123168/)
43- [Abort a process when FD ownership is violated](https://github.com/rust-lang/rust/pull/124210/)
44- [io::Write::write_fmt: panic if the formatter fails when the stream does not fail](https://github.com/rust-lang/rust/pull/125012/)
45- [Panic if `PathBuf::set_extension` would add a path separator](https://github.com/rust-lang/rust/pull/125070/)
46- [Add assert_unsafe_precondition to unchecked_{add,sub,neg,mul,shl,shr} methods](https://github.com/rust-lang/rust/pull/121571/)
47- [Update `c_char` on AIX to use the correct type](https://github.com/rust-lang/rust/pull/122986/)
48- [`offset_of!` no longer returns a temporary](https://github.com/rust-lang/rust/pull/124484/)
49- [Handle sigma in `str.to_lowercase` correctly](https://github.com/rust-lang/rust/pull/124773/)
50- [Raise `DEFAULT_MIN_STACK_SIZE` to at least 64KiB](https://github.com/rust-lang/rust/pull/126059/)
51
52<a id="1.80-Stabilized-APIs"></a>
53
54Stabilized APIs
55---------------
56- [`impl Default for Rc<CStr>`](https://doc.rust-lang.org/beta/alloc/rc/struct.Rc.html#impl-Default-for-Rc%3CCStr%3E)
57- [`impl Default for Rc<str>`](https://doc.rust-lang.org/beta/alloc/rc/struct.Rc.html#impl-Default-for-Rc%3Cstr%3E)
58- [`impl Default for Rc<[T]>`](https://doc.rust-lang.org/beta/alloc/rc/struct.Rc.html#impl-Default-for-Rc%3C%5BT%5D%3E)
59- [`impl Default for Arc<str>`](https://doc.rust-lang.org/beta/alloc/sync/struct.Arc.html#impl-Default-for-Arc%3Cstr%3E)
60- [`impl Default for Arc<CStr>`](https://doc.rust-lang.org/beta/alloc/sync/struct.Arc.html#impl-Default-for-Arc%3CCStr%3E)
61- [`impl Default for Arc<[T]>`](https://doc.rust-lang.org/beta/alloc/sync/struct.Arc.html#impl-Default-for-Arc%3C%5BT%5D%3E)
62- [`impl IntoIterator for Box<[T]>`](https://doc.rust-lang.org/beta/alloc/boxed/struct.Box.html#impl-IntoIterator-for-Box%3C%5BI%5D,+A%3E)
63- [`impl FromIterator<String> for Box<str>`](https://doc.rust-lang.org/beta/alloc/boxed/struct.Box.html#impl-FromIterator%3CString%3E-for-Box%3Cstr%3E)
64- [`impl FromIterator<char> for Box<str>`](https://doc.rust-lang.org/beta/alloc/boxed/struct.Box.html#impl-FromIterator%3Cchar%3E-for-Box%3Cstr%3E)
65- [`LazyCell`](https://doc.rust-lang.org/beta/core/cell/struct.LazyCell.html)
66- [`LazyLock`](https://doc.rust-lang.org/beta/std/sync/struct.LazyLock.html)
67- [`Duration::div_duration_f32`](https://doc.rust-lang.org/beta/std/time/struct.Duration.html#method.div_duration_f32)
68- [`Duration::div_duration_f64`](https://doc.rust-lang.org/beta/std/time/struct.Duration.html#method.div_duration_f64)
69- [`Option::take_if`](https://doc.rust-lang.org/beta/std/option/enum.Option.html#method.take_if)
70- [`Seek::seek_relative`](https://doc.rust-lang.org/beta/std/io/trait.Seek.html#method.seek_relative)
71- [`BinaryHeap::as_slice`](https://doc.rust-lang.org/beta/std/collections/struct.BinaryHeap.html#method.as_slice)
72- [`NonNull::offset`](https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.offset)
73- [`NonNull::byte_offset`](https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.byte_offset)
74- [`NonNull::add`](https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.add)
75- [`NonNull::byte_add`](https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.byte_add)
76- [`NonNull::sub`](https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.sub)
77- [`NonNull::byte_sub`](https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.byte_sub)
78- [`NonNull::offset_from`](https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.offset_from)
79- [`NonNull::byte_offset_from`](https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.byte_offset_from)
80- [`NonNull::read`](https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.read)
81- [`NonNull::read_volatile`](https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.read_volatile)
82- [`NonNull::read_unaligned`](https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.read_unaligned)
83- [`NonNull::write`](https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.write)
84- [`NonNull::write_volatile`](https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.write_volatile)
85- [`NonNull::write_unaligned`](https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.write_unaligned)
86- [`NonNull::write_bytes`](https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.write_bytes)
87- [`NonNull::copy_to`](https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.copy_to)
88- [`NonNull::copy_to_nonoverlapping`](https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.copy_to_nonoverlapping)
89- [`NonNull::copy_from`](https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.copy_from)
90- [`NonNull::copy_from_nonoverlapping`](https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.copy_from_nonoverlapping)
91- [`NonNull::replace`](https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.replace)
92- [`NonNull::swap`](https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.swap)
93- [`NonNull::drop_in_place`](https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.drop_in_place)
94- [`NonNull::align_offset`](https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.align_offset)
95- [`<[T]>::split_at_checked`](https://doc.rust-lang.org/beta/std/primitive.slice.html#method.split_at_checked)
96- [`<[T]>::split_at_mut_checked`](https://doc.rust-lang.org/beta/std/primitive.slice.html#method.split_at_mut_checked)
97- [`str::split_at_checked`](https://doc.rust-lang.org/beta/std/primitive.str.html#method.split_at_checked)
98- [`str::split_at_mut_checked`](https://doc.rust-lang.org/beta/std/primitive.str.html#method.split_at_mut_checked)
99- [`str::trim_ascii`](https://doc.rust-lang.org/beta/std/primitive.str.html#method.trim_ascii)
100- [`str::trim_ascii_start`](https://doc.rust-lang.org/beta/std/primitive.str.html#method.trim_ascii_start)
101- [`str::trim_ascii_end`](https://doc.rust-lang.org/beta/std/primitive.str.html#method.trim_ascii_end)
102- [`<[u8]>::trim_ascii`](https://doc.rust-lang.org/beta/core/primitive.slice.html#method.trim_ascii)
103- [`<[u8]>::trim_ascii_start`](https://doc.rust-lang.org/beta/core/primitive.slice.html#method.trim_ascii_start)
104- [`<[u8]>::trim_ascii_end`](https://doc.rust-lang.org/beta/core/primitive.slice.html#method.trim_ascii_end)
105- [`Ipv4Addr::BITS`](https://doc.rust-lang.org/beta/core/net/struct.Ipv4Addr.html#associatedconstant.BITS)
106- [`Ipv4Addr::to_bits`](https://doc.rust-lang.org/beta/core/net/struct.Ipv4Addr.html#method.to_bits)
107- [`Ipv4Addr::from_bits`](https://doc.rust-lang.org/beta/core/net/struct.Ipv4Addr.html#method.from_bits)
108- [`Ipv6Addr::BITS`](https://doc.rust-lang.org/beta/core/net/struct.Ipv6Addr.html#associatedconstant.BITS)
109- [`Ipv6Addr::to_bits`](https://doc.rust-lang.org/beta/core/net/struct.Ipv6Addr.html#method.to_bits)
110- [`Ipv6Addr::from_bits`](https://doc.rust-lang.org/beta/core/net/struct.Ipv6Addr.html#method.from_bits)
111- [`Vec::<[T; N]>::into_flattened`](https://doc.rust-lang.org/beta/alloc/vec/struct.Vec.html#method.into_flattened)
112- [`<[[T; N]]>::as_flattened`](https://doc.rust-lang.org/beta/core/primitive.slice.html#method.as_flattened)
113- [`<[[T; N]]>::as_flattened_mut`](https://doc.rust-lang.org/beta/core/primitive.slice.html#method.as_flattened_mut)
114
115These APIs are now stable in const contexts:
116
117- [`<[T]>::last_chunk`](https://doc.rust-lang.org/beta/core/primitive.slice.html#method.last_chunk)
118- [`BinaryHeap::new`](https://doc.rust-lang.org/beta/std/collections/struct.BinaryHeap.html#method.new)
119
120<a id="1.80-Cargo"></a>
121
122Cargo
123-----
124- [Stabilize `-Zcheck-cfg` as always enabled](https://github.com/rust-lang/cargo/pull/13571/)
125- [Warn, rather than fail publish, if a target is excluded](https://github.com/rust-lang/cargo/pull/13713/)
126- [Add special `check-cfg` lint config for the `unexpected_cfgs` lint](https://github.com/rust-lang/cargo/pull/13913/)
127- [Stabilize `cargo update --precise <yanked>`](https://github.com/rust-lang/cargo/pull/13974/)
128- [Don't change file permissions on `Cargo.toml` when using `cargo add`](https://github.com/rust-lang/cargo/pull/13898/)
129- [Support using `cargo fix` on IPv6-only networks](https://github.com/rust-lang/cargo/pull/13907/)
130
131<a id="1.80-Rustdoc"></a>
132
133Rustdoc
134-----
135
136- [Allow searching for references](https://github.com/rust-lang/rust/pull/124148/)
137- [Stabilize `custom_code_classes_in_docs` feature](https://github.com/rust-lang/rust/pull/124577/)
138- [fix: In cross-crate scenarios show enum variants on type aliases of enums](https://github.com/rust-lang/rust/pull/125300/)
139
140<a id="1.80-Compatibility-Notes"></a>
141
142Compatibility Notes
143-------------------
144- [rustfmt estimates line lengths differently when using non-ascii characters](https://github.com/rust-lang/rustfmt/issues/6203)
145- [Type aliases are now handled correctly in orphan check](https://github.com/rust-lang/rust/pull/117164/)
146- [Allow instructing rustdoc to read from stdin via `-`](https://github.com/rust-lang/rust/pull/124611/)
147- [`std::env::{set_var, remove_var}` can no longer be converted to safe function pointers and no longer implement the `Fn` family of traits](https://github.com/rust-lang/rust/pull/124636)
148- [Warn (or error) when `Self` constructor from outer item is referenced in inner nested item](https://github.com/rust-lang/rust/pull/124187/)
149- [Turn `indirect_structural_match` and `pointer_structural_match` lints into hard errors](https://github.com/rust-lang/rust/pull/124661/)
150- [Make `where_clause_object_safety` lint a regular object safety violation](https://github.com/rust-lang/rust/pull/125380/)
151- [Turn `proc_macro_back_compat` lint into a hard error.](https://github.com/rust-lang/rust/pull/125596/)
152- [Detect unused structs even when implementing private traits](https://github.com/rust-lang/rust/pull/122382/)
153- [`std::sync::ReentrantLockGuard<T>` is no longer `Sync` if `T: !Sync`](https://github.com/rust-lang/rust/pull/125527) which means [`std::io::StdoutLock` and `std::io::StderrLock` are no longer Sync](https://github.com/rust-lang/rust/issues/127340)
154
155<a id="1.80-Internal-Changes"></a>
156
157Internal Changes
158----------------
159
160These changes do not affect any public interfaces of Rust, but they represent
161significant improvements to the performance or internals of rustc and related
162tools.
163
164- Misc improvements to size of generated html by rustdoc e.g. [#124738](https://github.com/rust-lang/rust/pull/124738/) and [#123734](https://github.com/rust-lang/rust/pull/123734/)
165- [MSVC targets no longer depend on libc](https://github.com/rust-lang/rust/pull/124050/)
166
167Version 1.79.0 (2024-06-13)
168==========================
169
170<a id="1.79.0-Language"></a>
171
172Language
173--------
174- [Stabilize inline `const {}` expressions.](https://github.com/rust-lang/rust/pull/104087/)
175- [Prevent opaque types being instantiated twice with different regions within the same function.](https://github.com/rust-lang/rust/pull/116935/)
176- [Stabilize WebAssembly target features that are in phase 4 and 5.](https://github.com/rust-lang/rust/pull/117457/)
177- [Add the `redundant_lifetimes` lint to detect lifetimes which are semantically redundant.](https://github.com/rust-lang/rust/pull/118391/)
178- [Stabilize the `unnameable_types` lint for public types that can't be named.](https://github.com/rust-lang/rust/pull/120144/)
179- [Enable debuginfo in macros, and stabilize `-C collapse-macro-debuginfo` and `#[collapse_debuginfo]`.](https://github.com/rust-lang/rust/pull/120845/)
180- [Propagate temporary lifetime extension into `if` and `match` expressions.](https://github.com/rust-lang/rust/pull/121346/)
181- [Restrict promotion of `const fn` calls.](https://github.com/rust-lang/rust/pull/121557/)
182- [Warn against refining impls of crate-private traits with `refining_impl_trait` lint.](https://github.com/rust-lang/rust/pull/121720/)
183- [Stabilize associated type bounds (RFC 2289).](https://github.com/rust-lang/rust/pull/122055/)
184- [Stabilize importing `main` from other modules or crates.](https://github.com/rust-lang/rust/pull/122060/)
185- [Check return types of function types for well-formedness](https://github.com/rust-lang/rust/pull/115538)
186- [Rework `impl Trait` lifetime inference](https://github.com/rust-lang/rust/pull/116891/)
187- [Change inductive trait solver cycles to be ambiguous](https://github.com/rust-lang/rust/pull/122791)
188
189<a id="1.79.0-Compiler"></a>
190
191Compiler
192--------
193- [Define `-C strip` to only affect binaries, not artifacts like `.pdb`.](https://github.com/rust-lang/rust/pull/115120/)
194- [Stabilize `-Crelro-level` for controlling runtime link hardening.](https://github.com/rust-lang/rust/pull/121694/)
195- [Stabilize checking of `cfg` names and values at compile-time with `--check-cfg`.](https://github.com/rust-lang/rust/pull/123501/)
196 *Note that this only stabilizes the compiler part, the Cargo part is still unstable in this release.*
197- [Add `aarch64-apple-visionos` and `aarch64-apple-visionos-sim` tier 3 targets.](https://github.com/rust-lang/rust/pull/121419/)
198- [Add `riscv32ima-unknown-none-elf` tier 3 target.](https://github.com/rust-lang/rust/pull/122696/)
199- [Promote several Windows targets to tier 2](https://github.com/rust-lang/rust/pull/121712): `aarch64-pc-windows-gnullvm`, `i686-pc-windows-gnullvm`, and `x86_64-pc-windows-gnullvm`.
200
201Refer to Rust's [platform support page][platform-support-doc]
202for more information on Rust's tiered platform support.
203
204<a id="1.79.0-Libraries"></a>
205
206Libraries
207---------
208
209- [Implement `FromIterator` for `(impl Default + Extend, impl Default + Extend)`.](https://github.com/rust-lang/rust/pull/107462/)
210- [Implement `{Div,Rem}Assign<NonZero<X>>` on `X`.](https://github.com/rust-lang/rust/pull/121952/)
211- [Document overrides of `clone_from()` in core/std.](https://github.com/rust-lang/rust/pull/122201/)
212- [Link MSVC default lib in core.](https://github.com/rust-lang/rust/pull/122268/)
213- [Caution against using `transmute` between pointers and integers.](https://github.com/rust-lang/rust/pull/122379/)
214- [Enable frame pointers for the standard library.](https://github.com/rust-lang/rust/pull/122646/)
215
216<a id="1.79.0-Stabilized-APIs"></a>
217
218Stabilized APIs
219---------------
220
221- [`{integer}::unchecked_add`](https://doc.rust-lang.org/stable/core/primitive.i32.html#method.unchecked_add)
222- [`{integer}::unchecked_mul`](https://doc.rust-lang.org/stable/core/primitive.i32.html#method.unchecked_mul)
223- [`{integer}::unchecked_sub`](https://doc.rust-lang.org/stable/core/primitive.i32.html#method.unchecked_sub)
224- [`<[T]>::split_at_unchecked`](https://doc.rust-lang.org/stable/core/primitive.slice.html#method.split_at_unchecked)
225- [`<[T]>::split_at_mut_unchecked`](https://doc.rust-lang.org/stable/core/primitive.slice.html#method.split_at_mut_unchecked)
226- [`<[u8]>::utf8_chunks`](https://doc.rust-lang.org/stable/core/primitive.slice.html#method.utf8_chunks)
227- [`str::Utf8Chunks`](https://doc.rust-lang.org/stable/core/str/struct.Utf8Chunks.html)
228- [`str::Utf8Chunk`](https://doc.rust-lang.org/stable/core/str/struct.Utf8Chunk.html)
229- [`<*const T>::is_aligned`](https://doc.rust-lang.org/stable/core/primitive.pointer.html#method.is_aligned)
230- [`<*mut T>::is_aligned`](https://doc.rust-lang.org/stable/core/primitive.pointer.html#method.is_aligned-1)
231- [`NonNull::is_aligned`](https://doc.rust-lang.org/stable/core/ptr/struct.NonNull.html#method.is_aligned)
232- [`<*const [T]>::len`](https://doc.rust-lang.org/stable/core/primitive.pointer.html#method.len)
233- [`<*mut [T]>::len`](https://doc.rust-lang.org/stable/core/primitive.pointer.html#method.len-1)
234- [`<*const [T]>::is_empty`](https://doc.rust-lang.org/stable/core/primitive.pointer.html#method.is_empty)
235- [`<*mut [T]>::is_empty`](https://doc.rust-lang.org/stable/core/primitive.pointer.html#method.is_empty-1)
236- [`NonNull::<[T]>::is_empty`](https://doc.rust-lang.org/stable/core/ptr/struct.NonNull.html#method.is_empty)
237- [`CStr::count_bytes`](https://doc.rust-lang.org/stable/core/ffi/c_str/struct.CStr.html#method.count_bytes)
238- [`io::Error::downcast`](https://doc.rust-lang.org/stable/std/io/struct.Error.html#method.downcast)
239- [`num::NonZero<T>`](https://doc.rust-lang.org/stable/core/num/struct.NonZero.html)
240- [`path::absolute`](https://doc.rust-lang.org/stable/std/path/fn.absolute.html)
241- [`proc_macro::Literal::byte_character`](https://doc.rust-lang.org/stable/proc_macro/struct.Literal.html#method.byte_character)
242- [`proc_macro::Literal::c_string`](https://doc.rust-lang.org/stable/proc_macro/struct.Literal.html#method.c_string)
243
244These APIs are now stable in const contexts:
245
246- [`Atomic*::into_inner`](https://doc.rust-lang.org/stable/core/sync/atomic/struct.AtomicUsize.html#method.into_inner)
247- [`io::Cursor::new`](https://doc.rust-lang.org/stable/std/io/struct.Cursor.html#method.new)
248- [`io::Cursor::get_ref`](https://doc.rust-lang.org/stable/std/io/struct.Cursor.html#method.get_ref)
249- [`io::Cursor::position`](https://doc.rust-lang.org/stable/std/io/struct.Cursor.html#method.position)
250- [`io::empty`](https://doc.rust-lang.org/stable/std/io/fn.empty.html)
251- [`io::repeat`](https://doc.rust-lang.org/stable/std/io/fn.repeat.html)
252- [`io::sink`](https://doc.rust-lang.org/stable/std/io/fn.sink.html)
253- [`panic::Location::caller`](https://doc.rust-lang.org/stable/std/panic/struct.Location.html#method.caller)
254- [`panic::Location::file`](https://doc.rust-lang.org/stable/std/panic/struct.Location.html#method.file)
255- [`panic::Location::line`](https://doc.rust-lang.org/stable/std/panic/struct.Location.html#method.line)
256- [`panic::Location::column`](https://doc.rust-lang.org/stable/std/panic/struct.Location.html#method.column)
257
258<a id="1.79.0-Cargo"></a>
259
260Cargo
261-----
262
263- [Prevent dashes in `lib.name`, always normalizing to `_`.](https://github.com/rust-lang/cargo/pull/12783/)
264- [Stabilize MSRV-aware version requirement selection in `cargo add`.](https://github.com/rust-lang/cargo/pull/13608/)
265- [Switch to using `gitoxide` by default for listing files.](https://github.com/rust-lang/cargo/pull/13696/)
266
267<a id="1.79.0-Rustdoc"></a>
268
269Rustdoc
270-----
271
272- [Always display stability version even if it's the same as the containing item.](https://github.com/rust-lang/rust/pull/118441/)
273- [Show a single search result for items with multiple paths.](https://github.com/rust-lang/rust/pull/119912/)
274- [Support typing `/` in docs to begin a search.](https://github.com/rust-lang/rust/pull/123355/)
275
276<a id="1.79.0-Misc"></a>
277
278Misc
279----
280
281<a id="1.79.0-Compatibility-Notes"></a>
282
283Compatibility Notes
284-------------------
285
286- [Update the minimum external LLVM to 17.](https://github.com/rust-lang/rust/pull/122649/)
287- [`RustcEncodable` and `RustcDecodable` are soft-destabilized, to be removed
288 from the prelude in next edition.](https://github.com/rust-lang/rust/pull/116016/)
289- [The `wasm_c_abi` future-incompatibility lint will warn about use of the
290 non-spec-compliant C ABI.](https://github.com/rust-lang/rust/pull/117918/)
291 Use `wasm-bindgen v0.2.88` to generate forward-compatible bindings.
292- [Check return types of function types for well-formedness](https://github.com/rust-lang/rust/pull/115538)
293
294Version 1.78.0 (2024-05-02)
295==========================
296
297<a id="1.78.0-Language"></a>
298
299Language
300--------
301- [Stabilize `#[cfg(target_abi = ...)]`](https://github.com/rust-lang/rust/pull/119590/)
302- [Stabilize the `#[diagnostic]` namespace and `#[diagnostic::on_unimplemented]` attribute](https://github.com/rust-lang/rust/pull/119888/)
303- [Make async-fn-in-trait implementable with concrete signatures](https://github.com/rust-lang/rust/pull/120103/)
304- [Make matching on NaN a hard error, and remove the rest of `illegal_floating_point_literal_pattern`](https://github.com/rust-lang/rust/pull/116284/)
305- [static mut: allow mutable reference to arbitrary types, not just slices and arrays](https://github.com/rust-lang/rust/pull/117614/)
306- [Extend `invalid_reference_casting` to include references casting to bigger memory layout](https://github.com/rust-lang/rust/pull/118983/)
307- [Add `non_contiguous_range_endpoints` lint for singleton gaps after exclusive ranges](https://github.com/rust-lang/rust/pull/118879/)
308- [Add `wasm_c_abi` lint for use of older wasm-bindgen versions](https://github.com/rust-lang/rust/pull/117918/)
309 This lint currently only works when using Cargo.
310- [Update `indirect_structural_match` and `pointer_structural_match` lints to match RFC](https://github.com/rust-lang/rust/pull/120423/)
311- [Make non-`PartialEq`-typed consts as patterns a hard error](https://github.com/rust-lang/rust/pull/120805/)
312- [Split `refining_impl_trait` lint into `_reachable`, `_internal` variants](https://github.com/rust-lang/rust/pull/121720/)
313- [Remove unnecessary type inference when using associated types inside of higher ranked `where`-bounds](https://github.com/rust-lang/rust/pull/119849)
314- [Weaken eager detection of cyclic types during type inference](https://github.com/rust-lang/rust/pull/119989)
315- [`trait Trait: Auto {}`: allow upcasting from `dyn Trait` to `dyn Trait + Auto`](https://github.com/rust-lang/rust/pull/119338)
316
317<a id="1.78.0-Compiler"></a>
318
319Compiler
320--------
321
322- [Made `INVALID_DOC_ATTRIBUTES` lint deny by default](https://github.com/rust-lang/rust/pull/111505/)
323- [Increase accuracy of redundant `use` checking](https://github.com/rust-lang/rust/pull/117772/)
324- [Suggest moving definition if non-found macro_rules! is defined later](https://github.com/rust-lang/rust/pull/121130/)
325- [Lower transmutes from int to pointer type as gep on null](https://github.com/rust-lang/rust/pull/121282/)
326
327Target changes:
328
329- [Windows tier 1 targets now require at least Windows 10](https://github.com/rust-lang/rust/pull/115141/)
330 - [Enable CMPXCHG16B, SSE3, SAHF/LAHF and 128-bit Atomics in tier 1 Windows](https://github.com/rust-lang/rust/pull/120820/)
331- [Add `wasm32-wasip1` tier 2 (without host tools) target](https://github.com/rust-lang/rust/pull/120468/)
332- [Add `wasm32-wasip2` tier 3 target](https://github.com/rust-lang/rust/pull/119616/)
333- [Rename `wasm32-wasi-preview1-threads` to `wasm32-wasip1-threads`](https://github.com/rust-lang/rust/pull/122170/)
334- [Add `arm64ec-pc-windows-msvc` tier 3 target](https://github.com/rust-lang/rust/pull/119199/)
335- [Add `armv8r-none-eabihf` tier 3 target for the Cortex-R52](https://github.com/rust-lang/rust/pull/110482/)
336- [Add `loongarch64-unknown-linux-musl` tier 3 target](https://github.com/rust-lang/rust/pull/121832/)
337
338Refer to Rust's [platform support page][platform-support-doc]
339for more information on Rust's tiered platform support.
340
341<a id="1.78.0-Libraries"></a>
342
343Libraries
344---------
345
346- [Bump Unicode to version 15.1.0, regenerate tables](https://github.com/rust-lang/rust/pull/120777/)
347- [Make align_offset, align_to well-behaved in all cases](https://github.com/rust-lang/rust/pull/121201/)
348- [PartialEq, PartialOrd: document expectations for transitive chains](https://github.com/rust-lang/rust/pull/115386/)
349- [Optimize away poison guards when std is built with panic=abort](https://github.com/rust-lang/rust/pull/100603/)
350- [Replace pthread `RwLock` with custom implementation](https://github.com/rust-lang/rust/pull/110211/)
351- [Implement unwind safety for Condvar on all platforms](https://github.com/rust-lang/rust/pull/121768/)
352- [Add ASCII fast-path for `char::is_grapheme_extended`](https://github.com/rust-lang/rust/pull/121138/)
353
354<a id="1.78.0-Stabilized-APIs"></a>
355
356Stabilized APIs
357---------------
358
359- [`impl Read for &Stdin`](https://doc.rust-lang.org/stable/std/io/struct.Stdin.html#impl-Read-for-%26Stdin)
360- [Accept non `'static` lifetimes for several `std::error::Error` related implementations](https://github.com/rust-lang/rust/pull/113833/)
361- [Make `impl<Fd: AsFd>` impl take `?Sized`](https://github.com/rust-lang/rust/pull/114655/)
362- [`impl From<TryReserveError> for io::Error`](https://doc.rust-lang.org/stable/std/io/struct.Error.html#impl-From%3CTryReserveError%3E-for-Error)
363
364These APIs are now stable in const contexts:
365
366- [`Barrier::new()`](https://doc.rust-lang.org/stable/std/sync/struct.Barrier.html#method.new)
367
368<a id="1.78.0-Cargo"></a>
369
370Cargo
371-----
372
373- [Stabilize lockfile v4](https://github.com/rust-lang/cargo/pull/12852/)
374- [Respect `rust-version` when generating lockfile](https://github.com/rust-lang/cargo/pull/12861/)
375- [Control `--charset` via auto-detecting config value](https://github.com/rust-lang/cargo/pull/13337/)
376- [Support `target.<triple>.rustdocflags` officially](https://github.com/rust-lang/cargo/pull/13197/)
377- [Stabilize global cache data tracking](https://github.com/rust-lang/cargo/pull/13492/)
378
379<a id="1.78.0-Misc"></a>
380
381Misc
382----
383
384- [rustdoc: add `--test-builder-wrapper` arg to support wrappers such as RUSTC_WRAPPER when building doctests](https://github.com/rust-lang/rust/pull/114651/)
385
386<a id="1.78.0-Compatibility-Notes"></a>
387
388Compatibility Notes
389-------------------
390
391- [Many unsafe precondition checks now run for user code with debug assertions enabled](https://github.com/rust-lang/rust/pull/120594/)
392 This change helps users catch undefined behavior in their code, though the details of how much is checked are generally not stable.
393- [riscv only supports split_debuginfo=off for now](https://github.com/rust-lang/rust/pull/120518/)
394- [Consistently check bounds on hidden types of `impl Trait`](https://github.com/rust-lang/rust/pull/121679)
395- [Change equality of higher ranked types to not rely on subtyping](https://github.com/rust-lang/rust/pull/118247)
396- [When called, additionally check bounds on normalized function return type](https://github.com/rust-lang/rust/pull/118882)
397- [Expand coverage for `arithmetic_overflow` lint](https://github.com/rust-lang/rust/pull/119432/)
398- [Fix detection of potential interior mutability in `const` initializers](https://github.com/rust-lang/rust/issues/121250)
399 This code was accidentally accepted. The fix can break generic code that borrows a value of unknown type,
400 as there is currently no way to declare "this type has no interior mutability". In the future, stabilizing
401 the [`Freeze` trait](https://github.com/rust-lang/rust/issues/121675) will allow proper support for such code.
402
403<a id="1.78.0-Internal-Changes"></a>
404
405Internal Changes
406----------------
407
408These changes do not affect any public interfaces of Rust, but they represent
409significant improvements to the performance or internals of rustc and related
410tools.
411
412- [Update to LLVM 18](https://github.com/rust-lang/rust/pull/120055/)
413- [Build `rustc` with 1CGU on `x86_64-pc-windows-msvc`](https://github.com/rust-lang/rust/pull/112267/)
414- [Build `rustc` with 1CGU on `x86_64-apple-darwin`](https://github.com/rust-lang/rust/pull/112268/)
415- [Introduce `run-make` V2 infrastructure, a `run_make_support` library and port over 2 tests as example](https://github.com/rust-lang/rust/pull/113026/)
416- [Windows: Implement condvar, mutex and rwlock using futex](https://github.com/rust-lang/rust/pull/121956/)
417
418Version 1.77.2 (2024-04-09)
419===========================
420
421<a id="1.77.2"></a>
422
423- [CVE-2024-24576: fix escaping of Windows batch file arguments in `std::process::Command`](https://blog.rust-lang.org/2024/04/09/cve-2024-24576.html)
424
425Version 1.77.1 (2024-03-28)
426===========================
427
428<a id="1.77.1"></a>
429
430- [Revert stripping debuginfo by default for Windows](https://github.com/rust-lang/cargo/pull/13654)
431 This fixes a regression in 1.77 by reverting to the previous default.
432 Platforms other than Windows are not affected.
433- Internal: [Fix heading anchor rendering in doc pages](https://github.com/rust-lang/rust/pull/122693)
434
435Version 1.77.0 (2024-03-21)
436==========================
437
438<a id="1.77.0-Language"></a>
439
440Language
441--------
442
443- [Reveal opaque types within the defining body for exhaustiveness checking.](https://github.com/rust-lang/rust/pull/116821/)
444- [Stabilize C-string literals.](https://github.com/rust-lang/rust/pull/117472/)
445- [Stabilize THIR unsafeck.](https://github.com/rust-lang/rust/pull/117673/)
446- [Add lint `static_mut_refs` to warn on references to mutable statics.](https://github.com/rust-lang/rust/pull/117556/)
447- [Support async recursive calls (as long as they have indirection).](https://github.com/rust-lang/rust/pull/117703/)
448- [Undeprecate lint `unstable_features` and make use of it in the compiler.](https://github.com/rust-lang/rust/pull/118639/)
449- [Make inductive cycles in coherence ambiguous always.](https://github.com/rust-lang/rust/pull/118649/)
450- [Get rid of type-driven traversal in const-eval interning](https://github.com/rust-lang/rust/pull/119044/),
451 only as a [future compatiblity lint](https://github.com/rust-lang/rust/pull/122204) for now.
452- [Deny braced macro invocations in let-else.](https://github.com/rust-lang/rust/pull/119062/)
453
454<a id="1.77.0-Compiler"></a>
455
456Compiler
457--------
458
459- [Include lint `soft_unstable` in future breakage reports.](https://github.com/rust-lang/rust/pull/116274/)
460- [Make `i128` and `u128` 16-byte aligned on x86-based targets.](https://github.com/rust-lang/rust/pull/116672/)
461- [Use `--verbose` in diagnostic output.](https://github.com/rust-lang/rust/pull/119129/)
462- [Improve spacing between printed tokens.](https://github.com/rust-lang/rust/pull/120227/)
463- [Merge the `unused_tuple_struct_fields` lint into `dead_code`.](https://github.com/rust-lang/rust/pull/118297/)
464- [Error on incorrect implied bounds in well-formedness check](https://github.com/rust-lang/rust/pull/118553/),
465 with a temporary exception for Bevy.
466- [Fix coverage instrumentation/reports for non-ASCII source code.](https://github.com/rust-lang/rust/pull/119033/)
467- [Fix `fn`/`const` items implied bounds and well-formedness check.](https://github.com/rust-lang/rust/pull/120019/)
468- [Promote `riscv32{im|imafc}-unknown-none-elf` targets to tier 2.](https://github.com/rust-lang/rust/pull/118704/)
469- Add several new tier 3 targets:
470 - [`aarch64-unknown-illumos`](https://github.com/rust-lang/rust/pull/112936/)
471 - [`hexagon-unknown-none-elf`](https://github.com/rust-lang/rust/pull/117601/)
472 - [`riscv32imafc-esp-espidf`](https://github.com/rust-lang/rust/pull/119738/)
473 - [`riscv32im-risc0-zkvm-elf`](https://github.com/rust-lang/rust/pull/117958/)
474
475Refer to Rust's [platform support page][platform-support-doc]
476for more information on Rust's tiered platform support.
477
478<a id="1.77.0-Libraries"></a>
479
480Libraries
481---------
482
483- [Implement `From<&[T; N]>` for `Cow<[T]>`.](https://github.com/rust-lang/rust/pull/113489/)
484- [Remove special-case handling of `vec.split_off(0)`.](https://github.com/rust-lang/rust/pull/119917/)
485
486<a id="1.77.0-Stabilized-APIs"></a>
487
488Stabilized APIs
489---------------
490
491- [`array::each_ref`](https://doc.rust-lang.org/stable/std/primitive.array.html#method.each_ref)
492- [`array::each_mut`](https://doc.rust-lang.org/stable/std/primitive.array.html#method.each_mut)
493- [`core::net`](https://doc.rust-lang.org/stable/core/net/index.html)
494- [`f32::round_ties_even`](https://doc.rust-lang.org/stable/std/primitive.f32.html#method.round_ties_even)
495- [`f64::round_ties_even`](https://doc.rust-lang.org/stable/std/primitive.f64.html#method.round_ties_even)
496- [`mem::offset_of!`](https://doc.rust-lang.org/stable/std/mem/macro.offset_of.html)
497- [`slice::first_chunk`](https://doc.rust-lang.org/stable/std/primitive.slice.html#method.first_chunk)
498- [`slice::first_chunk_mut`](https://doc.rust-lang.org/stable/std/primitive.slice.html#method.first_chunk_mut)
499- [`slice::split_first_chunk`](https://doc.rust-lang.org/stable/std/primitive.slice.html#method.split_first_chunk)
500- [`slice::split_first_chunk_mut`](https://doc.rust-lang.org/stable/std/primitive.slice.html#method.split_first_chunk_mut)
501- [`slice::last_chunk`](https://doc.rust-lang.org/stable/std/primitive.slice.html#method.last_chunk)
502- [`slice::last_chunk_mut`](https://doc.rust-lang.org/stable/std/primitive.slice.html#method.last_chunk_mut)
503- [`slice::split_last_chunk`](https://doc.rust-lang.org/stable/std/primitive.slice.html#method.split_last_chunk)
504- [`slice::split_last_chunk_mut`](https://doc.rust-lang.org/stable/std/primitive.slice.html#method.split_last_chunk_mut)
505- [`slice::chunk_by`](https://doc.rust-lang.org/stable/std/primitive.slice.html#method.chunk_by)
506- [`slice::chunk_by_mut`](https://doc.rust-lang.org/stable/std/primitive.slice.html#method.chunk_by_mut)
507- [`Bound::map`](https://doc.rust-lang.org/stable/std/ops/enum.Bound.html#method.map)
508- [`File::create_new`](https://doc.rust-lang.org/stable/std/fs/struct.File.html#method.create_new)
509- [`Mutex::clear_poison`](https://doc.rust-lang.org/stable/std/sync/struct.Mutex.html#method.clear_poison)
510- [`RwLock::clear_poison`](https://doc.rust-lang.org/stable/std/sync/struct.RwLock.html#method.clear_poison)
511
512<a id="1.77.0-Cargo"></a>
513
514Cargo
515-----
516
517- [Extend the build directive syntax with `cargo::`.](https://github.com/rust-lang/cargo/pull/12201/)
518- [Stabilize metadata `id` format as `PackageIDSpec`.](https://github.com/rust-lang/cargo/pull/12914/)
519- [Pull out `cargo-util-schemas` as a crate.](https://github.com/rust-lang/cargo/pull/13178/)
520- [Strip all debuginfo when debuginfo is not requested.](https://github.com/rust-lang/cargo/pull/13257/)
521- [Inherit jobserver from env for all kinds of runners.](https://github.com/rust-lang/cargo/pull/12776/)
522- [Deprecate rustc plugin support in cargo.](https://github.com/rust-lang/cargo/pull/13248/)
523
524<a id="1.77.0-Rustdoc"></a>
525
526Rustdoc
527-----
528
529- [Allows links in markdown headings.](https://github.com/rust-lang/rust/pull/117662/)
530- [Search for tuples and unit by type with `()`.](https://github.com/rust-lang/rust/pull/118194/)
531- [Clean up the source sidebar's hide button.](https://github.com/rust-lang/rust/pull/119066/)
532- [Prevent JS injection from `localStorage`.](https://github.com/rust-lang/rust/pull/120250/)
533
534<a id="1.77.0-Misc"></a>
535
536Misc
537----
538
539- [Recommend version-sorting for all sorting in style guide.](https://github.com/rust-lang/rust/pull/115046/)
540
541<a id="1.77.0-Internal-Changes"></a>
542
543Internal Changes
544----------------
545
546These changes do not affect any public interfaces of Rust, but they represent
547significant improvements to the performance or internals of rustc and related
548tools.
549
550- [Add more weirdness to `weird-exprs.rs`.](https://github.com/rust-lang/rust/pull/119028/)
551
552Version 1.76.0 (2024-02-08)
553==========================
554
555<a id="1.76.0-Language"></a>
556
557Language
558--------
559- [Document Rust ABI compatibility between various types](https://github.com/rust-lang/rust/pull/115476/)
560- [Also: guarantee that char and u32 are ABI-compatible](https://github.com/rust-lang/rust/pull/118032/)
561- [Add lint `ambiguous_wide_pointer_comparisons` that supersedes `clippy::vtable_address_comparisons`](https://github.com/rust-lang/rust/pull/117758)
562
563<a id="1.76.0-Compiler"></a>
564
565Compiler
566--------
567- [Lint pinned `#[must_use]` pointers (in particular, `Box<T>` where `T` is `#[must_use]`) in `unused_must_use`.](https://github.com/rust-lang/rust/pull/118054/)
568- [Soundness fix: fix computing the offset of an unsized field in a packed struct](https://github.com/rust-lang/rust/pull/118540/)
569- [Soundness fix: fix dynamic size/align computation logic for packed types with dyn Trait tail](https://github.com/rust-lang/rust/pull/118538/)
570- [Add `$message_type` field to distinguish json diagnostic outputs](https://github.com/rust-lang/rust/pull/115691/)
571- [Enable Rust to use the EHCont security feature of Windows](https://github.com/rust-lang/rust/pull/118013/)
572- [Add tier 3 {x86_64,i686}-win7-windows-msvc targets](https://github.com/rust-lang/rust/pull/118150/)
573- [Add tier 3 aarch64-apple-watchos target](https://github.com/rust-lang/rust/pull/119074/)
574- [Add tier 3 arm64e-apple-ios & arm64e-apple-darwin targets](https://github.com/rust-lang/rust/pull/115526/)
575
576Refer to Rust's [platform support page][platform-support-doc]
577for more information on Rust's tiered platform support.
578
579<a id="1.76.0-Libraries"></a>
580
581Libraries
582---------
583- [Add a column number to `dbg!()`](https://github.com/rust-lang/rust/pull/114962/)
584- [Add `std::hash::{DefaultHasher, RandomState}` exports](https://github.com/rust-lang/rust/pull/115694/)
585- [Fix rounding issue with exponents in fmt](https://github.com/rust-lang/rust/pull/116301/)
586- [Add T: ?Sized to `RwLockReadGuard` and `RwLockWriteGuard`'s Debug impls.](https://github.com/rust-lang/rust/pull/117138/)
587- [Windows: Allow `File::create` to work on hidden files](https://github.com/rust-lang/rust/pull/116438/)
588
589<a id="1.76.0-Stabilized-APIs"></a>
590
591Stabilized APIs
592---------------
593
594- [`Arc::unwrap_or_clone`](https://doc.rust-lang.org/stable/std/sync/struct.Arc.html#method.unwrap_or_clone)
595- [`Rc::unwrap_or_clone`](https://doc.rust-lang.org/stable/std/rc/struct.Rc.html#method.unwrap_or_clone)
596- [`Result::inspect`](https://doc.rust-lang.org/stable/std/result/enum.Result.html#method.inspect)
597- [`Result::inspect_err`](https://doc.rust-lang.org/stable/std/result/enum.Result.html#method.inspect_err)
598- [`Option::inspect`](https://doc.rust-lang.org/stable/std/option/enum.Option.html#method.inspect)
599- [`type_name_of_val`](https://doc.rust-lang.org/stable/std/any/fn.type_name_of_val.html)
600- [`std::hash::{DefaultHasher, RandomState}`](https://doc.rust-lang.org/stable/std/hash/index.html#structs)
601 These were previously available only through `std::collections::hash_map`.
602- [`ptr::{from_ref, from_mut}`](https://doc.rust-lang.org/stable/std/ptr/fn.from_ref.html)
603- [`ptr::addr_eq`](https://doc.rust-lang.org/stable/std/ptr/fn.addr_eq.html)
604
605<a id="1.76.0-Cargo"></a>
606
607Cargo
608-----
609
610See [Cargo release notes](https://github.com/rust-lang/cargo/blob/master/CHANGELOG.md#cargo-176-2024-02-08).
611
612<a id="1.76.0-Rustdoc"></a>
613
614Rustdoc
615-------
616
617- [Don't merge cfg and doc(cfg) attributes for re-exports](https://github.com/rust-lang/rust/pull/113091/)
618- [rustdoc: allow resizing the sidebar / hiding the top bar](https://github.com/rust-lang/rust/pull/115660/)
619- [rustdoc-search: add support for traits and associated types](https://github.com/rust-lang/rust/pull/116085/)
620- [rustdoc: Add highlighting for comments in items declaration](https://github.com/rust-lang/rust/pull/117869/)
621
622<a id="1.76.0-Compatibility-Notes"></a>
623
624Compatibility Notes
625-------------------
626- [Add allow-by-default lint for unit bindings](https://github.com/rust-lang/rust/pull/112380/)
627 This is expected to be upgraded to a warning by default in a future Rust
628 release. Some macros emit bindings with type `()` with user-provided spans,
629 which means that this lint will warn for user code.
630- [Remove x86_64-sun-solaris target.](https://github.com/rust-lang/rust/pull/118091/)
631- [Remove asmjs-unknown-emscripten target](https://github.com/rust-lang/rust/pull/117338/)
632- [Report errors in jobserver inherited through environment variables](https://github.com/rust-lang/rust/pull/113730/)
633 This [may warn](https://github.com/rust-lang/rust/issues/120515) on benign problems too.
634- [Update the minimum external LLVM to 16.](https://github.com/rust-lang/rust/pull/117947/)
635- [Improve `print_tts`](https://github.com/rust-lang/rust/pull/114571/)
636 This change can break some naive manual parsing of token trees in proc macro
637 code which expect a particular structure after `.to_string()`, rather than just arbitrary Rust code.
638- [Make `IMPLIED_BOUNDS_ENTAILMENT` into a hard error from a lint](https://github.com/rust-lang/rust/pull/117984/)
639- [Vec's allocation behavior was changed when collecting some iterators](https://github.com/rust-lang/rust/pull/110353)
640 Allocation behavior is currently not specified, nevertheless changes can be surprising.
641 See [`impl FromIterator for Vec`](https://doc.rust-lang.org/nightly/std/vec/struct.Vec.html#impl-FromIterator%3CT%3E-for-Vec%3CT%3E)
642 for more details.
643- [Properly reject `default` on free const items](https://github.com/rust-lang/rust/pull/117818/)
644
645Version 1.75.0 (2023-12-28)
646==========================
647
648<a id="1.75.0-Language"></a>
649
650Language
651--------
652
653- [Stabilize `async fn` and return-position `impl Trait` in traits.](https://github.com/rust-lang/rust/pull/115822/)
654- [Allow function pointer signatures containing `&mut T` in `const` contexts.](https://github.com/rust-lang/rust/pull/116015/)
655- [Match `usize`/`isize` exhaustively with half-open ranges.](https://github.com/rust-lang/rust/pull/116692/)
656- [Guarantee that `char` has the same size and alignment as `u32`.](https://github.com/rust-lang/rust/pull/116894/)
657- [Document that the null pointer has the 0 address.](https://github.com/rust-lang/rust/pull/116988/)
658- [Allow partially moved values in `match`.](https://github.com/rust-lang/rust/pull/103208/)
659- [Add notes about non-compliant FP behavior on 32bit x86 targets.](https://github.com/rust-lang/rust/pull/113053/)
660- [Stabilize ratified RISC-V target features.](https://github.com/rust-lang/rust/pull/116485/)
661
662<a id="1.75.0-Compiler"></a>
663
664Compiler
665--------
666
667- [Rework negative coherence to properly consider impls that only partly overlap.](https://github.com/rust-lang/rust/pull/112875/)
668- [Bump `COINDUCTIVE_OVERLAP_IN_COHERENCE` to deny, and warn in dependencies.](https://github.com/rust-lang/rust/pull/116493/)
669- [Consider alias bounds when computing liveness in NLL.](https://github.com/rust-lang/rust/pull/116733/)
670- [Add the V (vector) extension to the `riscv64-linux-android` target spec.](https://github.com/rust-lang/rust/pull/116618/)
671- [Automatically enable cross-crate inlining for small functions](https://github.com/rust-lang/rust/pull/116505)
672- Add several new tier 3 targets:
673 - [`csky-unknown-linux-gnuabiv2hf`](https://github.com/rust-lang/rust/pull/117049/)
674 - [`i586-unknown-netbsd`](https://github.com/rust-lang/rust/pull/117170/)
675 - [`mipsel-unknown-netbsd`](https://github.com/rust-lang/rust/pull/117356/)
676
677Refer to Rust's [platform support page][platform-support-doc]
678for more information on Rust's tiered platform support.
679
680<a id="1.75.0-Libraries"></a>
681
682Libraries
683---------
684
685- [Override `Waker::clone_from` to avoid cloning `Waker`s unnecessarily.](https://github.com/rust-lang/rust/pull/96979/)
686- [Implement `BufRead` for `VecDeque<u8>`.](https://github.com/rust-lang/rust/pull/110604/)
687- [Implement `FusedIterator` for `DecodeUtf16` when the inner iterator does.](https://github.com/rust-lang/rust/pull/110729/)
688- [Implement `Not, Bit{And,Or}{,Assign}` for IP addresses.](https://github.com/rust-lang/rust/pull/113747/)
689- [Implement `Default` for `ExitCode`.](https://github.com/rust-lang/rust/pull/114589/)
690- [Guarantee representation of None in NPO](https://github.com/rust-lang/rust/pull/115333/)
691- [Document when atomic loads are guaranteed read-only.](https://github.com/rust-lang/rust/pull/115577/)
692- [Broaden the consequences of recursive TLS initialization.](https://github.com/rust-lang/rust/pull/116172/)
693- [Windows: Support sub-millisecond sleep.](https://github.com/rust-lang/rust/pull/116461/)
694- [Fix generic bound of `str::SplitInclusive`'s `DoubleEndedIterator` impl](https://github.com/rust-lang/rust/pull/100806/)
695- [Fix exit status / wait status on non-Unix `cfg(unix)` platforms.](https://github.com/rust-lang/rust/pull/115108/)
696
697<a id="1.75.0-Stabilized-APIs"></a>
698
699Stabilized APIs
700---------------
701
702- [`Atomic*::from_ptr`](https://doc.rust-lang.org/stable/core/sync/atomic/struct.AtomicUsize.html#method.from_ptr)
703- [`FileTimes`](https://doc.rust-lang.org/stable/std/fs/struct.FileTimes.html)
704- [`FileTimesExt`](https://doc.rust-lang.org/stable/std/os/windows/fs/trait.FileTimesExt.html)
705- [`File::set_modified`](https://doc.rust-lang.org/stable/std/fs/struct.File.html#method.set_modified)
706- [`File::set_times`](https://doc.rust-lang.org/stable/std/fs/struct.File.html#method.set_times)
707- [`IpAddr::to_canonical`](https://doc.rust-lang.org/stable/core/net/enum.IpAddr.html#method.to_canonical)
708- [`Ipv6Addr::to_canonical`](https://doc.rust-lang.org/stable/core/net/struct.Ipv6Addr.html#method.to_canonical)
709- [`Option::as_slice`](https://doc.rust-lang.org/stable/core/option/enum.Option.html#method.as_slice)
710- [`Option::as_mut_slice`](https://doc.rust-lang.org/stable/core/option/enum.Option.html#method.as_mut_slice)
711- [`pointer::byte_add`](https://doc.rust-lang.org/stable/core/primitive.pointer.html#method.byte_add)
712- [`pointer::byte_offset`](https://doc.rust-lang.org/stable/core/primitive.pointer.html#method.byte_offset)
713- [`pointer::byte_offset_from`](https://doc.rust-lang.org/stable/core/primitive.pointer.html#method.byte_offset_from)
714- [`pointer::byte_sub`](https://doc.rust-lang.org/stable/core/primitive.pointer.html#method.byte_sub)
715- [`pointer::wrapping_byte_add`](https://doc.rust-lang.org/stable/core/primitive.pointer.html#method.wrapping_byte_add)
716- [`pointer::wrapping_byte_offset`](https://doc.rust-lang.org/stable/core/primitive.pointer.html#method.wrapping_byte_offset)
717- [`pointer::wrapping_byte_sub`](https://doc.rust-lang.org/stable/core/primitive.pointer.html#method.wrapping_byte_sub)
718
719These APIs are now stable in const contexts:
720
721- [`Ipv6Addr::to_ipv4_mapped`](https://doc.rust-lang.org/stable/core/net/struct.Ipv6Addr.html#method.to_ipv4_mapped)
722- [`MaybeUninit::assume_init_read`](https://doc.rust-lang.org/stable/core/mem/union.MaybeUninit.html#method.assume_init_read)
723- [`MaybeUninit::zeroed`](https://doc.rust-lang.org/stable/core/mem/union.MaybeUninit.html#method.zeroed)
724- [`mem::discriminant`](https://doc.rust-lang.org/stable/core/mem/fn.discriminant.html)
725- [`mem::zeroed`](https://doc.rust-lang.org/stable/core/mem/fn.zeroed.html)
726
727<a id="1.75.0-Cargo"></a>
728
729Cargo
730-----
731
732- [Add new packages to `[workspace.members]` automatically.](https://github.com/rust-lang/cargo/pull/12779/)
733- [Allow version-less `Cargo.toml` manifests.](https://github.com/rust-lang/cargo/pull/12786/)
734- [Make browser links out of HTML file paths.](https://github.com/rust-lang/cargo/pull/12889)
735
736<a id="1.75.0-Rustdoc"></a>
737
738Rustdoc
739-------
740
741- [Accept less invalid Rust in rustdoc.](https://github.com/rust-lang/rust/pull/117450/)
742- [Document lack of object safety on affected traits.](https://github.com/rust-lang/rust/pull/113241/)
743- [Hide `#[repr(transparent)]` if it isn't part of the public ABI.](https://github.com/rust-lang/rust/pull/115439/)
744- [Show enum discriminant if it is a C-like variant.](https://github.com/rust-lang/rust/pull/116142/)
745
746<a id="1.75.0-Compatibility-Notes"></a>
747
748Compatibility Notes
749-------------------
750
751- [FreeBSD targets now require at least version 12.](https://github.com/rust-lang/rust/pull/114521/)
752- [Formally demote tier 2 MIPS targets to tier 3.](https://github.com/rust-lang/rust/pull/115238/)
753- [Make misalignment a hard error in `const` contexts.](https://github.com/rust-lang/rust/pull/115524/)
754- [Fix detecting references to packed unsized fields.](https://github.com/rust-lang/rust/pull/115583/)
755- [Remove support for compiler plugins.](https://github.com/rust-lang/rust/pull/116412/)
756
757<a id="1.75.0-Internal-Changes"></a>
758
759Internal Changes
760----------------
761
762These changes do not affect any public interfaces of Rust, but they represent
763significant improvements to the performance or internals of rustc and related
764tools.
765
766- [Optimize `librustc_driver.so` with BOLT.](https://github.com/rust-lang/rust/pull/116352/)
767- [Enable parallel rustc front end in dev and nightly builds.](https://github.com/rust-lang/rust/pull/117435/)
768- [Distribute `rustc-codegen-cranelift` as rustup component on the nightly channel.](https://github.com/rust-lang/rust/pull/81746/)
769
770Version 1.74.1 (2023-12-07)
771===========================
772
773- [Resolved spurious STATUS_ACCESS_VIOLATIONs in LLVM](https://github.com/rust-lang/rust/pull/118464)
774- [Clarify guarantees for std::mem::discriminant](https://github.com/rust-lang/rust/pull/118006)
775- [Fix some subtyping-related regressions](https://github.com/rust-lang/rust/pull/116415)
776
777Version 1.74.0 (2023-11-16)
778==========================
779
780<a id="1.74.0-Language"></a>
781
782Language
783--------
784
785- [Codify that `std::mem::Discriminant<T>` does not depend on any lifetimes in T](https://github.com/rust-lang/rust/pull/104299/)
786- [Replace `private_in_public` lint with `private_interfaces` and `private_bounds` per RFC 2145.](https://github.com/rust-lang/rust/pull/113126/)
787 Read more in [RFC 2145](https://rust-lang.github.io/rfcs/2145-type-privacy.html).
788- [Allow explicit `#[repr(Rust)]`](https://github.com/rust-lang/rust/pull/114201/)
789- [closure field capturing: don't depend on alignment of packed fields](https://github.com/rust-lang/rust/pull/115315/)
790- [Enable MIR-based drop-tracking for `async` blocks](https://github.com/rust-lang/rust/pull/107421/)
791- [Stabilize `impl_trait_projections`](https://github.com/rust-lang/rust/pull/115659)
792
793<a id="1.74.0-Compiler"></a>
794
795Compiler
796--------
797
798- [stabilize combining +bundle and +whole-archive link modifiers](https://github.com/rust-lang/rust/pull/113301/)
799- [Stabilize `PATH` option for `--print KIND=PATH`](https://github.com/rust-lang/rust/pull/114183/)
800- [Enable ASAN/LSAN/TSAN for `*-apple-ios-macabi`](https://github.com/rust-lang/rust/pull/115644/)
801- [Promote loongarch64-unknown-none* to Tier 2](https://github.com/rust-lang/rust/pull/115368/)
802- [Add `i686-pc-windows-gnullvm` as a tier 3 target](https://github.com/rust-lang/rust/pull/115687/)
803
804<a id="1.74.0-Libraries"></a>
805
806Libraries
807---------
808
809- [Implement `From<OwnedFd/Handle>` for ChildStdin/out/err](https://github.com/rust-lang/rust/pull/98704/)
810- [Implement `From<{&,&mut} [T; N]>` for `Vec<T>` where `T: Clone`](https://github.com/rust-lang/rust/pull/111278/)
811- [impl Step for IP addresses](https://github.com/rust-lang/rust/pull/113748/)
812- [Implement `From<[T; N]>` for `Rc<[T]>` and `Arc<[T]>`](https://github.com/rust-lang/rust/pull/114041/)
813- [`impl TryFrom<char> for u16`](https://github.com/rust-lang/rust/pull/114065/)
814- [Stabilize `io_error_other` feature](https://github.com/rust-lang/rust/pull/115453/)
815- [Stabilize the `Saturating` type](https://github.com/rust-lang/rust/pull/115477/)
816- [Stabilize const_transmute_copy](https://github.com/rust-lang/rust/pull/115520/)
817
818<a id="1.74.0-Stabilized-APIs"></a>
819
820Stabilized APIs
821---------------
822
823- [`core::num::Saturating`](https://doc.rust-lang.org/stable/std/num/struct.Saturating.html)
824- [`impl From<io::Stdout> for std::process::Stdio`](https://doc.rust-lang.org/stable/std/process/struct.Stdio.html#impl-From%3CStdout%3E-for-Stdio)
825- [`impl From<io::Stderr> for std::process::Stdio`](https://doc.rust-lang.org/stable/std/process/struct.Stdio.html#impl-From%3CStderr%3E-for-Stdio)
826- [`impl From<OwnedHandle> for std::process::Child{Stdin, Stdout, Stderr}`](https://doc.rust-lang.org/stable/std/process/struct.ChildStderr.html#impl-From%3COwnedHandle%3E-for-ChildStderr)
827- [`impl From<OwnedFd> for std::process::Child{Stdin, Stdout, Stderr}`](https://doc.rust-lang.org/stable/std/process/struct.ChildStderr.html#impl-From%3COwnedFd%3E-for-ChildStderr)
828- [`std::ffi::OsString::from_encoded_bytes_unchecked`](https://doc.rust-lang.org/stable/std/ffi/struct.OsString.html#method.from_encoded_bytes_unchecked)
829- [`std::ffi::OsString::into_encoded_bytes`](https://doc.rust-lang.org/stable/std/ffi/struct.OsString.html#method.into_encoded_bytes)
830- [`std::ffi::OsStr::from_encoded_bytes_unchecked`](https://doc.rust-lang.org/stable/std/ffi/struct.OsStr.html#method.from_encoded_bytes_unchecked)
831- [`std::ffi::OsStr::as_encoded_bytes`](https://doc.rust-lang.org/stable/std/ffi/struct.OsStr.html#method.as_encoded_bytes)
832- [`std::io::Error::other`](https://doc.rust-lang.org/stable/std/io/struct.Error.html#method.other)
833- [`impl TryFrom<char> for u16`](https://doc.rust-lang.org/stable/std/primitive.u16.html#impl-TryFrom%3Cchar%3E-for-u16)
834- [`impl<T: Clone, const N: usize> From<&[T; N]> for Vec<T>`](https://doc.rust-lang.org/stable/std/vec/struct.Vec.html#impl-From%3C%26%5BT;+N%5D%3E-for-Vec%3CT,+Global%3E)
835- [`impl<T: Clone, const N: usize> From<&mut [T; N]> for Vec<T>`](https://doc.rust-lang.org/stable/std/vec/struct.Vec.html#impl-From%3C%26mut+%5BT;+N%5D%3E-for-Vec%3CT,+Global%3E)
836- [`impl<T, const N: usize> From<[T; N]> for Arc<[T]>`](https://doc.rust-lang.org/stable/std/sync/struct.Arc.html#impl-From%3C%5BT;+N%5D%3E-for-Arc%3C%5BT%5D,+Global%3E)
837- [`impl<T, const N: usize> From<[T; N]> for Rc<[T]>`](https://doc.rust-lang.org/stable/std/rc/struct.Rc.html#impl-From%3C%5BT;+N%5D%3E-for-Rc%3C%5BT%5D,+Global%3E)
838
839These APIs are now stable in const contexts:
840
841- [`core::mem::transmute_copy`](https://doc.rust-lang.org/beta/std/mem/fn.transmute_copy.html)
842- [`str::is_ascii`](https://doc.rust-lang.org/beta/std/primitive.str.html#method.is_ascii)
843- [`[u8]::is_ascii`](https://doc.rust-lang.org/beta/std/primitive.slice.html#method.is_ascii)
844
845<a id="1.74.0-Cargo"></a>
846
847Cargo
848-----
849
850- [In `Cargo.toml`, stabilize `[lints]`](https://github.com/rust-lang/cargo/pull/12648/)
851- [Stabilize credential-process and registry-auth](https://github.com/rust-lang/cargo/pull/12649/)
852- [Stabilize `--keep-going` build flag](https://github.com/rust-lang/cargo/pull/12568/)
853- [Add styling to `--help` output](https://github.com/rust-lang/cargo/pull/12578/)
854- [For `cargo clean`, add `--dry-run` flag and summary line at the end](https://github.com/rust-lang/cargo/pull/12638)
855- [For `cargo update`, make `--package` more convenient by being positional](https://github.com/rust-lang/cargo/pull/12545/)
856- [For `cargo update`, clarify meaning of --aggressive as --recursive](https://github.com/rust-lang/cargo/pull/12544/)
857- [Add '-n' as an alias for `--dry-run`](https://github.com/rust-lang/cargo/pull/12660/)
858- [Allow version-prefixes in pkgid's (e.g. `--package` flags) to resolve ambiguities](https://github.com/rust-lang/cargo/pull/12614/)
859- [In `.cargo/config.toml`, merge lists in precedence order](https://github.com/rust-lang/cargo/pull/12515/)
860- [Add support for `target.'cfg(..)'.linker`](https://github.com/rust-lang/cargo/pull/12535/)
861
862<a id="1.74.0-Rustdoc"></a>
863
864Rustdoc
865-------
866
867- [Add warning block support in rustdoc](https://github.com/rust-lang/rust/pull/106561/)
868- [rustdoc-search: add support for type parameters](https://github.com/rust-lang/rust/pull/112725/)
869- [rustdoc: show inner enum and struct in type definition for concrete type](https://github.com/rust-lang/rust/pull/114855/)
870
871<a id="1.74.0-Compatibility-Notes"></a>
872
873Compatibility Notes
874-------------------
875
876- [Raise minimum supported Apple OS versions](https://github.com/rust-lang/rust/pull/104385/)
877- [make Cell::swap panic if the Cells partially overlap](https://github.com/rust-lang/rust/pull/114795/)
878- [Reject invalid crate names in `--extern`](https://github.com/rust-lang/rust/pull/116001/)
879- [Don't resolve generic impls that may be shadowed by dyn built-in impls](https://github.com/rust-lang/rust/pull/114941/)
880- [The new `impl From<{&,&mut} [T; N]> for Vec<T>` is known to cause some inference failures with overly-generic code.](https://github.com/rust-lang/rust/issues/117054) In those examples using the `tui` crate, the combination of `AsRef<_>` and `Into<Vec>` leaves the middle type ambiguous, and the new `impl` adds another possibility, so it now requires an explicit type annotation.
881
882<a id="1.74.0-Internal-Changes"></a>
883
884Internal Changes
885----------------
886
887These changes do not affect any public interfaces of Rust, but they represent
888significant improvements to the performance or internals of rustc and related
889tools.
890
891None this cycle.
892
893Version 1.73.0 (2023-10-05)
894==========================
895
896<a id="1.73.0-Language"></a>
897
898Language
899--------
900
901- [Uplift `clippy::fn_null_check` lint as `useless_ptr_null_checks`.](https://github.com/rust-lang/rust/pull/111717/)
902- [Make `noop_method_call` warn by default.](https://github.com/rust-lang/rust/pull/111916/)
903- [Support interpolated block for `try` and `async` in macros.](https://github.com/rust-lang/rust/pull/112953/)
904- [Make `unconditional_recursion` lint detect recursive drops.](https://github.com/rust-lang/rust/pull/113902/)
905- [Future compatibility warning for some impls being incorrectly considered not overlapping.](https://github.com/rust-lang/rust/pull/114023/)
906- [The `invalid_reference_casting` lint is now **deny-by-default** (instead of allow-by-default)](https://github.com/rust-lang/rust/pull/112431)
907
908<a id="1.73.0-Compiler"></a>
909
910Compiler
911--------
912
913- [Write version information in a `.comment` section like GCC/Clang.](https://github.com/rust-lang/rust/pull/97550/)
914- [Add documentation on v0 symbol mangling.](https://github.com/rust-lang/rust/pull/97571/)
915- [Stabilize `extern "thiscall"` and `"thiscall-unwind"` ABIs.](https://github.com/rust-lang/rust/pull/114562/)
916- [Only check outlives goals on impl compared to trait.](https://github.com/rust-lang/rust/pull/109356/)
917- [Infer type in irrefutable slice patterns with fixed length as array.](https://github.com/rust-lang/rust/pull/113199/)
918- [Discard default auto trait impls if explicit ones exist.](https://github.com/rust-lang/rust/pull/113312/)
919- Add several new tier 3 targets:
920 - [`aarch64-unknown-teeos`](https://github.com/rust-lang/rust/pull/113480/)
921 - [`csky-unknown-linux-gnuabiv2`](https://github.com/rust-lang/rust/pull/113658/)
922 - [`riscv64-linux-android`](https://github.com/rust-lang/rust/pull/112858/)
923 - [`riscv64gc-unknown-hermit`](https://github.com/rust-lang/rust/pull/114004/)
924 - [`x86_64-unikraft-linux-musl`](https://github.com/rust-lang/rust/pull/113411/)
925 - [`x86_64-unknown-linux-ohos`](https://github.com/rust-lang/rust/pull/113061/)
926- [Add `wasm32-wasi-preview1-threads` as a tier 2 target.](https://github.com/rust-lang/rust/pull/112922/)
927
928Refer to Rust's [platform support page][platform-support-doc]
929for more information on Rust's tiered platform support.
930
931<a id="1.73.0-Libraries"></a>
932
933Libraries
934---------
935
936- [Add `Read`, `Write` and `Seek` impls for `Arc<File>`.](https://github.com/rust-lang/rust/pull/94748/)
937- [Merge functionality of `io::Sink` into `io::Empty`.](https://github.com/rust-lang/rust/pull/98154/)
938- [Implement `RefUnwindSafe` for `Backtrace`](https://github.com/rust-lang/rust/pull/100455/)
939- [Make `ExitStatus` implement `Default`](https://github.com/rust-lang/rust/pull/106425/)
940- [`impl SliceIndex<str> for (Bound<usize>, Bound<usize>)`](https://github.com/rust-lang/rust/pull/111081/)
941- [Change default panic handler message format.](https://github.com/rust-lang/rust/pull/112849/)
942- [Cleaner `assert_eq!` & `assert_ne!` panic messages.](https://github.com/rust-lang/rust/pull/111071/)
943- [Correct the (deprecated) Android `stat` struct definitions.](https://github.com/rust-lang/rust/pull/113130/)
944
945<a id="1.73.0-Stabilized-APIs"></a>
946
947Stabilized APIs
948---------------
949
950- [Unsigned `{integer}::div_ceil`](https://doc.rust-lang.org/stable/std/primitive.u32.html#method.div_ceil)
951- [Unsigned `{integer}::next_multiple_of`](https://doc.rust-lang.org/stable/std/primitive.u32.html#method.next_multiple_of)
952- [Unsigned `{integer}::checked_next_multiple_of`](https://doc.rust-lang.org/stable/std/primitive.u32.html#method.checked_next_multiple_of)
953- [`std::ffi::FromBytesUntilNulError`](https://doc.rust-lang.org/stable/std/ffi/struct.FromBytesUntilNulError.html)
954- [`std::os::unix::fs::chown`](https://doc.rust-lang.org/stable/std/os/unix/fs/fn.chown.html)
955- [`std::os::unix::fs::fchown`](https://doc.rust-lang.org/stable/std/os/unix/fs/fn.fchown.html)
956- [`std::os::unix::fs::lchown`](https://doc.rust-lang.org/stable/std/os/unix/fs/fn.lchown.html)
957- [`LocalKey::<Cell<T>>::get`](https://doc.rust-lang.org/stable/std/thread/struct.LocalKey.html#method.get)
958- [`LocalKey::<Cell<T>>::set`](https://doc.rust-lang.org/stable/std/thread/struct.LocalKey.html#method.set)
959- [`LocalKey::<Cell<T>>::take`](https://doc.rust-lang.org/stable/std/thread/struct.LocalKey.html#method.take)
960- [`LocalKey::<Cell<T>>::replace`](https://doc.rust-lang.org/stable/std/thread/struct.LocalKey.html#method.replace)
961- [`LocalKey::<RefCell<T>>::with_borrow`](https://doc.rust-lang.org/stable/std/thread/struct.LocalKey.html#method.with_borrow)
962- [`LocalKey::<RefCell<T>>::with_borrow_mut`](https://doc.rust-lang.org/stable/std/thread/struct.LocalKey.html#method.with_borrow_mut)
963- [`LocalKey::<RefCell<T>>::set`](https://doc.rust-lang.org/stable/std/thread/struct.LocalKey.html#method.set-1)
964- [`LocalKey::<RefCell<T>>::take`](https://doc.rust-lang.org/stable/std/thread/struct.LocalKey.html#method.take-1)
965- [`LocalKey::<RefCell<T>>::replace`](https://doc.rust-lang.org/stable/std/thread/struct.LocalKey.html#method.replace-1)
966
967These APIs are now stable in const contexts:
968
969- [`rc::Weak::new`](https://doc.rust-lang.org/stable/alloc/rc/struct.Weak.html#method.new)
970- [`sync::Weak::new`](https://doc.rust-lang.org/stable/alloc/sync/struct.Weak.html#method.new)
971- [`NonNull::as_ref`](https://doc.rust-lang.org/stable/core/ptr/struct.NonNull.html#method.as_ref)
972
973<a id="1.73.0-Cargo"></a>
974
975Cargo
976-----
977
978- [Bail out an error when using `cargo::` in custom build script.](https://github.com/rust-lang/cargo/pull/12332/)
979
980<a id="1.73.0-Misc"></a>
981
982Misc
983----
984
985<a id="1.73.0-Compatibility-Notes"></a>
986
987Compatibility Notes
988-------------------
989
990- [Update the minimum external LLVM to 15.](https://github.com/rust-lang/rust/pull/114148/)
991- [Check for non-defining uses of return position `impl Trait`.](https://github.com/rust-lang/rust/pull/112842/)
992
993<a id="1.73.0-Internal-Changes"></a>
994
995Internal Changes
996----------------
997
998These changes do not affect any public interfaces of Rust, but they represent
999significant improvements to the performance or internals of rustc and related
1000tools.
1001
1002- [Remove LLVM pointee types, supporting only opaque pointers.](https://github.com/rust-lang/rust/pull/105545/)
1003- [Port PGO/LTO/BOLT optimized build pipeline to Rust.](https://github.com/rust-lang/rust/pull/112235/)
1004- [Replace in-tree `rustc_apfloat` with the new version of the crate.](https://github.com/rust-lang/rust/pull/113843/)
1005- [Update to LLVM 17.](https://github.com/rust-lang/rust/pull/114048/)
1006- [Add `internal_features` lint for internal unstable features.](https://github.com/rust-lang/rust/pull/108955/)
1007- [Mention style for new syntax in tracking issue template.](https://github.com/rust-lang/rust/pull/113586/)
1008
1009Version 1.72.1 (2023-09-19)
1010===========================
1011
1012- [Adjust codegen change to improve LLVM codegen](https://github.com/rust-lang/rust/pull/115236)
1013- [rustdoc: Fix self ty params in objects with lifetimes](https://github.com/rust-lang/rust/pull/115276)
1014- [Fix regression in compile times](https://github.com/rust-lang/rust/pull/114948)
1015- Resolve some ICE regressions in the compiler:
1016 - [#115215](https://github.com/rust-lang/rust/pull/115215)
1017 - [#115559](https://github.com/rust-lang/rust/pull/115559)
1018
1019Version 1.72.0 (2023-08-24)
1020==========================
1021
1022<a id="1.72.0-Language"></a>
1023
1024Language
1025--------
1026
1027- [Replace const eval limit by a lint and add an exponential backoff warning](https://github.com/rust-lang/rust/pull/103877/)
1028- [expand: Change how `#![cfg(FALSE)]` behaves on crate root](https://github.com/rust-lang/rust/pull/110141/)
1029- [Stabilize inline asm for LoongArch64](https://github.com/rust-lang/rust/pull/111235/)
1030- [Uplift `clippy::undropped_manually_drops` lint](https://github.com/rust-lang/rust/pull/111530/)
1031- [Uplift `clippy::invalid_utf8_in_unchecked` lint](https://github.com/rust-lang/rust/pull/111543/) as `invalid_from_utf8_unchecked` and `invalid_from_utf8`
1032- [Uplift `clippy::cast_ref_to_mut` lint](https://github.com/rust-lang/rust/pull/111567/) as `invalid_reference_casting`
1033- [Uplift `clippy::cmp_nan` lint](https://github.com/rust-lang/rust/pull/111818/) as `invalid_nan_comparisons`
1034- [resolve: Remove artificial import ambiguity errors](https://github.com/rust-lang/rust/pull/112086/)
1035- [Don't require associated types with Self: Sized bounds in `dyn Trait` objects](https://github.com/rust-lang/rust/pull/112319/)
1036
1037<a id="1.72.0-Compiler"></a>
1038
1039Compiler
1040--------
1041
1042- [Remember names of `cfg`-ed out items to mention them in diagnostics](https://github.com/rust-lang/rust/pull/109005/)
1043- [Support for native WASM exceptions](https://github.com/rust-lang/rust/pull/111322/)
1044- [Add support for NetBSD/aarch64-be (big-endian arm64).](https://github.com/rust-lang/rust/pull/111326/)
1045- [Write to stdout if `-` is given as output file](https://github.com/rust-lang/rust/pull/111626/)
1046- [Force all native libraries to be statically linked when linking a static binary](https://github.com/rust-lang/rust/pull/111698/)
1047- [Add Tier 3 support for `loongarch64-unknown-none*`](https://github.com/rust-lang/rust/pull/112310/)
1048- [Prevent `.eh_frame` from being emitted for `-C panic=abort`](https://github.com/rust-lang/rust/pull/112403/)
1049- [Support 128-bit enum variant in debuginfo codegen](https://github.com/rust-lang/rust/pull/112474/)
1050- [compiler: update solaris/illumos to enable tsan support.](https://github.com/rust-lang/rust/pull/112039/)
1051
1052Refer to Rust's [platform support page][platform-support-doc]
1053for more information on Rust's tiered platform support.
1054
1055<a id="1.72.0-Libraries"></a>
1056
1057Libraries
1058---------
1059
1060- [Document memory orderings of `thread::{park, unpark}`](https://github.com/rust-lang/rust/pull/99587/)
1061- [io: soften ‘at most one write attempt’ requirement in io::Write::write](https://github.com/rust-lang/rust/pull/107200/)
1062- [Specify behavior of HashSet::insert](https://github.com/rust-lang/rust/pull/107619/)
1063- [Relax implicit `T: Sized` bounds on `BufReader<T>`, `BufWriter<T>` and `LineWriter<T>`](https://github.com/rust-lang/rust/pull/111074/)
1064- [Update runtime guarantee for `select_nth_unstable`](https://github.com/rust-lang/rust/pull/111974/)
1065- [Return `Ok` on kill if process has already exited](https://github.com/rust-lang/rust/pull/112594/)
1066- [Implement PartialOrd for `Vec`s over different allocators](https://github.com/rust-lang/rust/pull/112632/)
1067- [Use 128 bits for TypeId hash](https://github.com/rust-lang/rust/pull/109953/)
1068- [Don't drain-on-drop in DrainFilter impls of various collections.](https://github.com/rust-lang/rust/pull/104455/)
1069- [Make `{Arc,Rc,Weak}::ptr_eq` ignore pointer metadata](https://github.com/rust-lang/rust/pull/106450/)
1070
1071<a id="1.72.0-Rustdoc"></a>
1072
1073Rustdoc
1074-------
1075
1076- [Allow whitespace as path separator like double colon](https://github.com/rust-lang/rust/pull/108537/)
1077- [Add search result item types after their name](https://github.com/rust-lang/rust/pull/110688/)
1078- [Search for slices and arrays by type with `[]`](https://github.com/rust-lang/rust/pull/111958/)
1079- [Clean up type unification and "unboxing"](https://github.com/rust-lang/rust/pull/112233/)
1080
1081<a id="1.72.0-Stabilized-APIs"></a>
1082
1083Stabilized APIs
1084---------------
1085
1086- [`impl<T: Send> Sync for mpsc::Sender<T>`](https://doc.rust-lang.org/stable/std/sync/mpsc/struct.Sender.html#impl-Sync-for-Sender%3CT%3E)
1087- [`impl TryFrom<&OsStr> for &str`](https://doc.rust-lang.org/stable/std/primitive.str.html#impl-TryFrom%3C%26'a+OsStr%3E-for-%26'a+str)
1088- [`String::leak`](https://doc.rust-lang.org/stable/alloc/string/struct.String.html#method.leak)
1089
1090These APIs are now stable in const contexts:
1091
1092- [`CStr::from_bytes_with_nul`](https://doc.rust-lang.org/stable/std/ffi/struct.CStr.html#method.from_bytes_with_nul)
1093- [`CStr::to_bytes`](https://doc.rust-lang.org/stable/std/ffi/struct.CStr.html#method.to_bytes)
1094- [`CStr::to_bytes_with_nul`](https://doc.rust-lang.org/stable/std/ffi/struct.CStr.html#method.to_bytes_with_nul)
1095- [`CStr::to_str`](https://doc.rust-lang.org/stable/std/ffi/struct.CStr.html#method.to_str)
1096
1097<a id="1.72.0-Cargo"></a>
1098
1099Cargo
1100-----
1101
1102- Enable `-Zdoctest-in-workspace` by default. When running each documentation
1103 test, the working directory is set to the root directory of the package the
1104 test belongs to.
1105 [docs](https://doc.rust-lang.org/nightly/cargo/commands/cargo-test.html#working-directory-of-tests)
1106 [#12221](https://github.com/rust-lang/cargo/pull/12221)
1107 [#12288](https://github.com/rust-lang/cargo/pull/12288)
1108- Add support of the "default" keyword to reset previously set `build.jobs`
1109 parallelism back to the default.
1110 [#12222](https://github.com/rust-lang/cargo/pull/12222)
1111
1112<a id="1.72.0-Compatibility-Notes"></a>
1113
1114Compatibility Notes
1115-------------------
1116
1117- [Alter `Display` for `Ipv6Addr` for IPv4-compatible addresses](https://github.com/rust-lang/rust/pull/112606/)
1118- Cargo changed feature name validation check to a hard error. The warning was
1119 added in Rust 1.49. These extended characters aren't allowed on crates.io, so
1120 this should only impact users of other registries, or people who don't publish
1121 to a registry.
1122 [#12291](https://github.com/rust-lang/cargo/pull/12291)
1123- [Demoted `mips*-unknown-linux-gnu*` targets from host tier 2 to target tier 3 support.](https://github.com/rust-lang/rust/pull/113274)
1124
1125Version 1.71.1 (2023-08-03)
1126===========================
1127
1128- [Fix CVE-2023-38497: Cargo did not respect the umask when extracting dependencies](https://github.com/rust-lang/cargo/security/advisories/GHSA-j3xp-wfr4-hx87)
1129- [Fix bash completion for users of Rustup](https://github.com/rust-lang/rust/pull/113579)
1130- [Do not show `suspicious_double_ref_op` lint when calling `borrow()`](https://github.com/rust-lang/rust/pull/112517)
1131- [Fix ICE: substitute types before checking inlining compatibility](https://github.com/rust-lang/rust/pull/113802)
1132- [Fix ICE: don't use `can_eq` in `derive(..)` suggestion for missing method](https://github.com/rust-lang/rust/pull/111516)
1133- [Fix building Rust 1.71.0 from the source tarball](https://github.com/rust-lang/rust/issues/113678)
1134
1135Version 1.71.0 (2023-07-13)
1136==========================
1137
1138<a id="1.71.0-Language"></a>
1139
1140Language
1141--------
1142
1143- [Stabilize `raw-dylib`, `link_ordinal`, `import_name_type` and `-Cdlltool`.](https://github.com/rust-lang/rust/pull/109677/)
1144- [Uplift `clippy::{drop,forget}_{ref,copy}` lints.](https://github.com/rust-lang/rust/pull/109732/)
1145- [Type inference is more conservative around constrained vars.](https://github.com/rust-lang/rust/pull/110100/)
1146- [Use fulfillment to check `Drop` impl compatibility](https://github.com/rust-lang/rust/pull/110577/)
1147
1148<a id="1.71.0-Compiler"></a>
1149
1150Compiler
1151--------
1152
1153- [Evaluate place expression in `PlaceMention`](https://github.com/rust-lang/rust/pull/104844/),
1154 making `let _ =` patterns more consistent with respect to the borrow checker.
1155- [Add `--print deployment-target` flag for Apple targets.](https://github.com/rust-lang/rust/pull/105354/)
1156- [Stabilize `extern "C-unwind"` and friends.](https://github.com/rust-lang/rust/pull/106075/)
1157 The existing `extern "C"` etc. may change behavior for cross-language unwinding in a future release.
1158- [Update the version of musl used on `*-linux-musl` targets to 1.2.3](https://github.com/rust-lang/rust/pull/107129/),
1159 enabling [time64](https://musl.libc.org/time64.html) on 32-bit systems.
1160- [Stabilize `debugger_visualizer`](https://github.com/rust-lang/rust/pull/108668/)
1161 for embedding metadata like Microsoft's Natvis.
1162- [Enable flatten-format-args by default.](https://github.com/rust-lang/rust/pull/109999/)
1163- [Make `Self` respect tuple constructor privacy.](https://github.com/rust-lang/rust/pull/111245/)
1164- [Improve niche placement by trying two strategies and picking the better result.](https://github.com/rust-lang/rust/pull/108106/)
1165- [Use `apple-m1` as the target CPU for `aarch64-apple-darwin`.](https://github.com/rust-lang/rust/pull/109899/)
1166- [Add Tier 3 support for the `x86_64h-apple-darwin` target.](https://github.com/rust-lang/rust/pull/108795/)
1167- [Promote `loongarch64-unknown-linux-gnu` to Tier 2 with host tools.](https://github.com/rust-lang/rust/pull/110936/)
1168
1169Refer to Rust's [platform support page][platform-support-doc]
1170for more information on Rust's tiered platform support.
1171
1172<a id="1.71.0-Libraries"></a>
1173
1174Libraries
1175---------
1176- [Rework handling of recursive panics.](https://github.com/rust-lang/rust/pull/110975/)
1177 Additional panics are allowed while unwinding, as long as they are caught before escaping
1178 a `Drop` implementation, but panicking within a panic hook is now an immediate abort.
1179- [Loosen `From<&[T]> for Box<[T]>` bound to `T: Clone`.](https://github.com/rust-lang/rust/pull/103406/)
1180- [Remove unnecessary `T: Send` bound](https://github.com/rust-lang/rust/pull/111134/)
1181 in `Error for mpsc::SendError<T>` and `TrySendError<T>`.
1182- [Fix docs for `alloc::realloc`](https://github.com/rust-lang/rust/pull/108630/)
1183 to match `Layout` requirements that the size must not exceed `isize::MAX`.
1184- [Document `const {}` syntax for `std::thread_local`.](https://github.com/rust-lang/rust/pull/110620/)
1185 This syntax was stabilized in Rust 1.59, but not previously mentioned in release notes.
1186
1187<a id="1.71.0-Stabilized-APIs"></a>
1188
1189Stabilized APIs
1190---------------
1191
1192- [`CStr::is_empty`](https://doc.rust-lang.org/stable/std/ffi/struct.CStr.html#method.is_empty)
1193- [`BuildHasher::hash_one`](https://doc.rust-lang.org/stable/std/hash/trait.BuildHasher.html#method.hash_one)
1194- [`NonZeroI*::is_positive`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroI32.html#method.is_positive)
1195- [`NonZeroI*::is_negative`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroI32.html#method.is_negative)
1196- [`NonZeroI*::checked_neg`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroI32.html#method.checked_neg)
1197- [`NonZeroI*::overflowing_neg`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroI32.html#method.overflowing_neg)
1198- [`NonZeroI*::saturating_neg`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroI32.html#method.saturating_neg)
1199- [`NonZeroI*::wrapping_neg`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroI32.html#method.wrapping_neg)
1200- [`Neg for NonZeroI*`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroI32.html#impl-Neg-for-NonZeroI32)
1201- [`Neg for &NonZeroI*`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroI32.html#impl-Neg-for-%26NonZeroI32)
1202- [`From<[T; N]> for (T...)`](https://doc.rust-lang.org/stable/std/primitive.array.html#impl-From%3C%5BT;+1%5D%3E-for-(T,))
1203 (array to N-tuple for N in 1..=12)
1204- [`From<(T...)> for [T; N]`](https://doc.rust-lang.org/stable/std/primitive.array.html#impl-From%3C(T,)%3E-for-%5BT;+1%5D)
1205 (N-tuple to array for N in 1..=12)
1206- [`windows::io::AsHandle for Box<T>`](https://doc.rust-lang.org/stable/std/os/windows/io/trait.AsHandle.html#impl-AsHandle-for-Box%3CT%3E)
1207- [`windows::io::AsHandle for Rc<T>`](https://doc.rust-lang.org/stable/std/os/windows/io/trait.AsHandle.html#impl-AsHandle-for-Rc%3CT%3E)
1208- [`windows::io::AsHandle for Arc<T>`](https://doc.rust-lang.org/stable/std/os/windows/io/trait.AsHandle.html#impl-AsHandle-for-Arc%3CT%3E)
1209- [`windows::io::AsSocket for Box<T>`](https://doc.rust-lang.org/stable/std/os/windows/io/trait.AsSocket.html#impl-AsSocket-for-Box%3CT%3E)
1210- [`windows::io::AsSocket for Rc<T>`](https://doc.rust-lang.org/stable/std/os/windows/io/trait.AsSocket.html#impl-AsSocket-for-Rc%3CT%3E)
1211- [`windows::io::AsSocket for Arc<T>`](https://doc.rust-lang.org/stable/std/os/windows/io/trait.AsSocket.html#impl-AsSocket-for-Arc%3CT%3E)
1212
1213These APIs are now stable in const contexts:
1214
1215- [`<*const T>::read`](https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.read)
1216- [`<*const T>::read_unaligned`](https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.read_unaligned)
1217- [`<*mut T>::read`](https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.read-1)
1218- [`<*mut T>::read_unaligned`](https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.read_unaligned-1)
1219- [`ptr::read`](https://doc.rust-lang.org/stable/std/ptr/fn.read.html)
1220- [`ptr::read_unaligned`](https://doc.rust-lang.org/stable/std/ptr/fn.read_unaligned.html)
1221- [`<[T]>::split_at`](https://doc.rust-lang.org/stable/std/primitive.slice.html#method.split_at)
1222
1223<a id="1.71.0-Cargo"></a>
1224
1225Cargo
1226-----
1227- [Allow named debuginfo options in `Cargo.toml`.](https://github.com/rust-lang/cargo/pull/11958/)
1228- [Add `workspace_default_members` to the output of `cargo metadata`.](https://github.com/rust-lang/cargo/pull/11978/)
1229- [Automatically inherit workspace fields when running `cargo new`/`cargo init`.](https://github.com/rust-lang/cargo/pull/12069/)
1230
1231<a id="1.71.0-Rustdoc"></a>
1232
1233Rustdoc
1234-------
1235
1236- [Add a new `rustdoc::unescaped_backticks` lint for broken inline code.](https://github.com/rust-lang/rust/pull/105848/)
1237- [Support strikethrough with single tildes.](https://github.com/rust-lang/rust/pull/111152/) (`~~old~~` vs. `~new~`)
1238
1239<a id="1.71.0-Misc"></a>
1240
1241Misc
1242----
1243
1244<a id="1.71.0-Compatibility-Notes"></a>
1245
1246Compatibility Notes
1247-------------------
1248
1249- [Remove structural match from `TypeId`.](https://github.com/rust-lang/rust/pull/103291/)
1250 Code that uses a constant `TypeId` in a pattern will potentially be broken.
1251 Known cases have already been fixed -- in particular, users of the `log`
1252 crate's `kv_unstable` feature should update to `log v0.4.18` or later.
1253- [Add a `sysroot` crate to represent the standard library crates.](https://github.com/rust-lang/rust/pull/108865/)
1254 This does not affect stable users, but may require adjustment in tools that build their own standard library.
1255- [Cargo optimizes its usage under `rustup`.](https://github.com/rust-lang/cargo/pull/11917/) When
1256 Cargo detects it will run `rustc` pointing to a rustup proxy, it'll try bypassing the proxy and
1257 use the underlying binary directly. There are assumptions around the interaction with rustup and
1258 `RUSTUP_TOOLCHAIN`. However, it's not expected to affect normal users.
1259- [When querying a package, Cargo tries only the original name, all hyphens, and all underscores to
1260 handle misspellings.](https://github.com/rust-lang/cargo/pull/12083/) Previously, Cargo tried each
1261 combination of hyphens and underscores, causing excessive requests to crates.io.
1262- Cargo now [disallows `RUSTUP_HOME`](https://github.com/rust-lang/cargo/pull/12101/) and
1263 [`RUSTUP_TOOLCHAIN`](https://github.com/rust-lang/cargo/pull/12107/) in the `[env]` configuration
1264 table. This is considered to be not a use case Cargo would like to support, since it will likely
1265 cause problems or lead to confusion.
1266
1267<a id="1.71.0-Internal-Changes"></a>
1268
1269Internal Changes
1270----------------
1271
1272These changes do not affect any public interfaces of Rust, but they represent
1273significant improvements to the performance or internals of rustc and related
1274tools.
1275
1276
1277Version 1.70.0 (2023-06-01)
1278==========================
1279
1280<a id="1.70.0-Language"></a>
1281
1282Language
1283--------
1284- [Relax ordering rules for `asm!` operands](https://github.com/rust-lang/rust/pull/105798/)
1285- [Properly allow macro expanded `format_args` invocations to uses captures](https://github.com/rust-lang/rust/pull/106505/)
1286- [Lint ambiguous glob re-exports](https://github.com/rust-lang/rust/pull/107880/)
1287- [Perform const and unsafe checking for expressions in `let _ = expr` position.](https://github.com/rust-lang/rust/pull/102256/)
1288
1289<a id="1.70.0-Compiler"></a>
1290
1291Compiler
1292--------
1293- [Extend -Cdebuginfo with new options and named aliases](https://github.com/rust-lang/rust/pull/109808/)
1294 This provides a smaller version of debuginfo for cases that only need line number information
1295 (`-Cdebuginfo=line-tables-only`), which may eventually become the default for `-Cdebuginfo=1`.
1296- [Make `unused_allocation` lint against `Box::new` too](https://github.com/rust-lang/rust/pull/104363/)
1297- [Detect uninhabited types early in const eval](https://github.com/rust-lang/rust/pull/109435/)
1298- [Switch to LLD as default linker for {arm,thumb}v4t-none-eabi](https://github.com/rust-lang/rust/pull/109721/)
1299- [Add tier 3 target `loongarch64-unknown-linux-gnu`](https://github.com/rust-lang/rust/pull/96971)
1300- [Add tier 3 target for `i586-pc-nto-qnx700` (QNX Neutrino RTOS, version 7.0)](https://github.com/rust-lang/rust/pull/109173/),
1301- [Insert alignment checks for pointer dereferences as debug assertions](https://github.com/rust-lang/rust/pull/98112)
1302 This catches undefined behavior at runtime, and may cause existing code to fail.
1303
1304Refer to Rust's [platform support page][platform-support-doc]
1305for more information on Rust's tiered platform support.
1306
1307<a id="1.70.0-Libraries"></a>
1308
1309Libraries
1310---------
1311- [Document NonZeroXxx layout guarantees](https://github.com/rust-lang/rust/pull/94786/)
1312- [Windows: make `Command` prefer non-verbatim paths](https://github.com/rust-lang/rust/pull/96391/)
1313- [Implement Default for some alloc/core iterators](https://github.com/rust-lang/rust/pull/99929/)
1314- [Fix handling of trailing bare CR in str::lines](https://github.com/rust-lang/rust/pull/100311/)
1315- [allow negative numeric literals in `concat!`](https://github.com/rust-lang/rust/pull/106844/)
1316- [Add documentation about the memory layout of `Cell`](https://github.com/rust-lang/rust/pull/106921/)
1317- [Use `partial_cmp` to implement tuple `lt`/`le`/`ge`/`gt`](https://github.com/rust-lang/rust/pull/108157/)
1318- [Stabilize `atomic_as_ptr`](https://github.com/rust-lang/rust/pull/108419/)
1319- [Stabilize `nonnull_slice_from_raw_parts`](https://github.com/rust-lang/rust/pull/97506/)
1320- [Partial stabilization of `once_cell`](https://github.com/rust-lang/rust/pull/105587/)
1321- [Stabilize `nonzero_min_max`](https://github.com/rust-lang/rust/pull/106633/)
1322- [Flatten/inline format_args!() and (string and int) literal arguments into format_args!()](https://github.com/rust-lang/rust/pull/106824/)
1323- [Stabilize movbe target feature](https://github.com/rust-lang/rust/pull/107711/)
1324- [don't splice from files into pipes in io::copy](https://github.com/rust-lang/rust/pull/108283/)
1325- [Add a builtin unstable `FnPtr` trait that is implemented for all function pointers](https://github.com/rust-lang/rust/pull/108080/)
1326 This extends `Debug`, `Pointer`, `Hash`, `PartialEq`, `Eq`, `PartialOrd`, and `Ord`
1327 implementations for function pointers with all ABIs.
1328
1329<a id="1.70.0-Stabilized-APIs"></a>
1330
1331Stabilized APIs
1332---------------
1333
1334- [`NonZero*::MIN/MAX`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroI8.html#associatedconstant.MIN)
1335- [`BinaryHeap::retain`](https://doc.rust-lang.org/stable/std/collections/struct.BinaryHeap.html#method.retain)
1336- [`Default for std::collections::binary_heap::IntoIter`](https://doc.rust-lang.org/stable/std/collections/binary_heap/struct.IntoIter.html)
1337- [`Default for std::collections::btree_map::{IntoIter, Iter, IterMut}`](https://doc.rust-lang.org/stable/std/collections/btree_map/struct.IntoIter.html)
1338- [`Default for std::collections::btree_map::{IntoKeys, Keys}`](https://doc.rust-lang.org/stable/std/collections/btree_map/struct.IntoKeys.html)
1339- [`Default for std::collections::btree_map::{IntoValues, Values}`](https://doc.rust-lang.org/stable/std/collections/btree_map/struct.IntoValues.html)
1340- [`Default for std::collections::btree_map::Range`](https://doc.rust-lang.org/stable/std/collections/btree_map/struct.Range.html)
1341- [`Default for std::collections::btree_set::{IntoIter, Iter}`](https://doc.rust-lang.org/stable/std/collections/btree_set/struct.IntoIter.html)
1342- [`Default for std::collections::btree_set::Range`](https://doc.rust-lang.org/stable/std/collections/btree_set/struct.Range.html)
1343- [`Default for std::collections::linked_list::{IntoIter, Iter, IterMut}`](https://doc.rust-lang.org/stable/alloc/collections/linked_list/struct.IntoIter.html)
1344- [`Default for std::vec::IntoIter`](https://doc.rust-lang.org/stable/alloc/vec/struct.IntoIter.html#impl-Default-for-IntoIter%3CT,+A%3E)
1345- [`Default for std::iter::Chain`](https://doc.rust-lang.org/stable/std/iter/struct.Chain.html)
1346- [`Default for std::iter::Cloned`](https://doc.rust-lang.org/stable/std/iter/struct.Cloned.html)
1347- [`Default for std::iter::Copied`](https://doc.rust-lang.org/stable/std/iter/struct.Copied.html)
1348- [`Default for std::iter::Enumerate`](https://doc.rust-lang.org/stable/std/iter/struct.Enumerate.html)
1349- [`Default for std::iter::Flatten`](https://doc.rust-lang.org/stable/std/iter/struct.Flatten.html)
1350- [`Default for std::iter::Fuse`](https://doc.rust-lang.org/stable/std/iter/struct.Fuse.html)
1351- [`Default for std::iter::Rev`](https://doc.rust-lang.org/stable/std/iter/struct.Rev.html)
1352- [`Default for std::slice::Iter`](https://doc.rust-lang.org/stable/std/slice/struct.Iter.html)
1353- [`Default for std::slice::IterMut`](https://doc.rust-lang.org/stable/std/slice/struct.IterMut.html)
1354- [`Rc::into_inner`](https://doc.rust-lang.org/stable/alloc/rc/struct.Rc.html#method.into_inner)
1355- [`Arc::into_inner`](https://doc.rust-lang.org/stable/alloc/sync/struct.Arc.html#method.into_inner)
1356- [`std::cell::OnceCell`](https://doc.rust-lang.org/stable/std/cell/struct.OnceCell.html)
1357- [`Option::is_some_and`](https://doc.rust-lang.org/stable/std/option/enum.Option.html#method.is_some_and)
1358- [`NonNull::slice_from_raw_parts`](https://doc.rust-lang.org/stable/std/ptr/struct.NonNull.html#method.slice_from_raw_parts)
1359- [`Result::is_ok_and`](https://doc.rust-lang.org/stable/std/result/enum.Result.html#method.is_ok_and)
1360- [`Result::is_err_and`](https://doc.rust-lang.org/stable/std/result/enum.Result.html#method.is_err_and)
1361- [`std::sync::atomic::Atomic*::as_ptr`](https://doc.rust-lang.org/stable/std/sync/atomic/struct.AtomicU8.html#method.as_ptr)
1362- [`std::io::IsTerminal`](https://doc.rust-lang.org/stable/std/io/trait.IsTerminal.html)
1363- [`std::os::linux::net::SocketAddrExt`](https://doc.rust-lang.org/stable/std/os/linux/net/trait.SocketAddrExt.html)
1364- [`std::os::unix::net::UnixDatagram::bind_addr`](https://doc.rust-lang.org/stable/std/os/unix/net/struct.UnixDatagram.html#method.bind_addr)
1365- [`std::os::unix::net::UnixDatagram::connect_addr`](https://doc.rust-lang.org/stable/std/os/unix/net/struct.UnixDatagram.html#method.connect_addr)
1366- [`std::os::unix::net::UnixDatagram::send_to_addr`](https://doc.rust-lang.org/stable/std/os/unix/net/struct.UnixDatagram.html#method.send_to_addr)
1367- [`std::os::unix::net::UnixListener::bind_addr`](https://doc.rust-lang.org/stable/std/os/unix/net/struct.UnixListener.html#method.bind_addr)
1368- [`std::path::Path::as_mut_os_str`](https://doc.rust-lang.org/stable/std/path/struct.Path.html#method.as_mut_os_str)
1369- [`std::sync::OnceLock`](https://doc.rust-lang.org/stable/std/sync/struct.OnceLock.html)
1370
1371<a id="1.70.0-Cargo"></a>
1372
1373Cargo
1374-----
1375
1376- [Add `CARGO_PKG_README`](https://github.com/rust-lang/cargo/pull/11645/)
1377- [Make `sparse` the default protocol for crates.io](https://github.com/rust-lang/cargo/pull/11791/)
1378- [Accurately show status when downgrading dependencies](https://github.com/rust-lang/cargo/pull/11839/)
1379- [Use registry.default for login/logout](https://github.com/rust-lang/cargo/pull/11949/)
1380- [Stabilize `cargo logout`](https://github.com/rust-lang/cargo/pull/11950/)
1381
1382<a id="1.70.0-Misc"></a>
1383
1384Misc
1385----
1386
1387- [Stabilize rustdoc `--test-run-directory`](https://github.com/rust-lang/rust/pull/103682/)
1388
1389<a id="1.70.0-Compatibility-Notes"></a>
1390
1391Compatibility Notes
1392-------------------
1393
1394- [Prevent stable `libtest` from supporting `-Zunstable-options`](https://github.com/rust-lang/rust/pull/109044/)
1395- [Perform const and unsafe checking for expressions in `let _ = expr` position.](https://github.com/rust-lang/rust/pull/102256/)
1396- [WebAssembly targets enable `sign-ext` and `mutable-globals` features in codegen](https://github.com/rust-lang/rust/issues/109807)
1397 This may cause incompatibility with older execution environments.
1398- [Insert alignment checks for pointer dereferences as debug assertions](https://github.com/rust-lang/rust/pull/98112)
1399 This catches undefined behavior at runtime, and may cause existing code to fail.
1400
1401<a id="1.70.0-Internal-Changes"></a>
1402
1403Internal Changes
1404----------------
1405
1406These changes do not affect any public interfaces of Rust, but they represent
1407significant improvements to the performance or internals of rustc and related
1408tools.
1409
1410- [Upgrade to LLVM 16](https://github.com/rust-lang/rust/pull/109474/)
1411- [Use SipHash-1-3 instead of SipHash-2-4 for StableHasher](https://github.com/rust-lang/rust/pull/107925/)
1412
1413Version 1.69.0 (2023-04-20)
1414==========================
1415
1416<a id="1.69.0-Language"></a>
1417
1418Language
1419--------
1420
1421- [Deriving built-in traits on packed structs works with `Copy` fields.](https://github.com/rust-lang/rust/pull/104429/)
1422- [Stabilize the `cmpxchg16b` target feature on x86 and x86_64.](https://github.com/rust-lang/rust/pull/106774/)
1423- [Improve analysis of trait bounds for associated types.](https://github.com/rust-lang/rust/pull/103695/)
1424- [Allow associated types to be used as union fields.](https://github.com/rust-lang/rust/pull/106938/)
1425- [Allow `Self: Autotrait` bounds on dyn-safe trait methods.](https://github.com/rust-lang/rust/pull/107082/)
1426- [Treat `str` as containing `[u8]` for auto trait purposes.](https://github.com/rust-lang/rust/pull/107941/)
1427
1428<a id="1.69.0-Compiler"></a>
1429
1430Compiler
1431--------
1432
1433- [Upgrade `*-pc-windows-gnu` on CI to mingw-w64 v10 and GCC 12.2.](https://github.com/rust-lang/rust/pull/100178/)
1434- [Rework min_choice algorithm of member constraints.](https://github.com/rust-lang/rust/pull/105300/)
1435- [Support `true` and `false` as boolean flags in compiler arguments.](https://github.com/rust-lang/rust/pull/107043/)
1436- [Default `repr(C)` enums to `c_int` size.](https://github.com/rust-lang/rust/pull/107592/)
1437
1438<a id="1.69.0-Libraries"></a>
1439
1440Libraries
1441---------
1442
1443- [Implement the unstable `DispatchFromDyn` for cell types, allowing downstream experimentation with custom method receivers.](https://github.com/rust-lang/rust/pull/97373/)
1444- [Document that `fmt::Arguments::as_str()` may return `Some(_)` in more cases after optimization, subject to change.](https://github.com/rust-lang/rust/pull/106823/)
1445- [Implement `AsFd` and `AsRawFd` for `Rc`.](https://github.com/rust-lang/rust/pull/107317/)
1446
1447<a id="1.69.0-Stabilized-APIs"></a>
1448
1449Stabilized APIs
1450---------------
1451
1452- [`CStr::from_bytes_until_nul`](https://doc.rust-lang.org/stable/core/ffi/struct.CStr.html#method.from_bytes_until_nul)
1453- [`core::ffi::FromBytesUntilNulError`](https://doc.rust-lang.org/stable/core/ffi/struct.FromBytesUntilNulError.html)
1454
1455These APIs are now stable in const contexts:
1456
1457- [`SocketAddr::new`](https://doc.rust-lang.org/stable/std/net/enum.SocketAddr.html#method.new)
1458- [`SocketAddr::ip`](https://doc.rust-lang.org/stable/std/net/enum.SocketAddr.html#method.ip)
1459- [`SocketAddr::port`](https://doc.rust-lang.org/stable/std/net/enum.SocketAddr.html#method.port)
1460- [`SocketAddr::is_ipv4`](https://doc.rust-lang.org/stable/std/net/enum.SocketAddr.html#method.is_ipv4)
1461- [`SocketAddr::is_ipv6`](https://doc.rust-lang.org/stable/std/net/enum.SocketAddr.html#method.is_ipv6)
1462- [`SocketAddrV4::new`](https://doc.rust-lang.org/stable/std/net/struct.SocketAddrV4.html#method.new)
1463- [`SocketAddrV4::ip`](https://doc.rust-lang.org/stable/std/net/struct.SocketAddrV4.html#method.ip)
1464- [`SocketAddrV4::port`](https://doc.rust-lang.org/stable/std/net/struct.SocketAddrV4.html#method.port)
1465- [`SocketAddrV6::new`](https://doc.rust-lang.org/stable/std/net/struct.SocketAddrV6.html#method.new)
1466- [`SocketAddrV6::ip`](https://doc.rust-lang.org/stable/std/net/struct.SocketAddrV6.html#method.ip)
1467- [`SocketAddrV6::port`](https://doc.rust-lang.org/stable/std/net/struct.SocketAddrV6.html#method.port)
1468- [`SocketAddrV6::flowinfo`](https://doc.rust-lang.org/stable/std/net/struct.SocketAddrV6.html#method.flowinfo)
1469- [`SocketAddrV6::scope_id`](https://doc.rust-lang.org/stable/std/net/struct.SocketAddrV6.html#method.scope_id)
1470
1471<a id="1.69.0-Cargo"></a>
1472
1473Cargo
1474-----
1475
1476- [Cargo now suggests `cargo fix` or `cargo clippy --fix` when compilation warnings are auto-fixable.](https://github.com/rust-lang/cargo/pull/11558/)
1477- [Cargo now suggests `cargo add` if you try to install a library crate.](https://github.com/rust-lang/cargo/pull/11410/)
1478- [Cargo now sets the `CARGO_BIN_NAME` environment variable also for binary examples.](https://github.com/rust-lang/cargo/pull/11705/)
1479
1480<a id="1.69.0-Rustdoc"></a>
1481
1482Rustdoc
1483-----
1484
1485- [Vertically compact trait bound formatting.](https://github.com/rust-lang/rust/pull/102842/)
1486- [Only include stable lints in `rustdoc::all` group.](https://github.com/rust-lang/rust/pull/106316/)
1487- [Compute maximum Levenshtein distance based on the query.](https://github.com/rust-lang/rust/pull/107141/)
1488- [Remove inconsistently-present sidebar tooltips.](https://github.com/rust-lang/rust/pull/107490/)
1489- [Search by macro when query ends with `!`.](https://github.com/rust-lang/rust/pull/108143/)
1490
1491<a id="1.69.0-Compatibility-Notes"></a>
1492
1493Compatibility Notes
1494-------------------
1495
1496- [The `rust-analysis` component from `rustup` now only contains a warning placeholder.](https://github.com/rust-lang/rust/pull/101841/) This was primarily intended for RLS, and the corresponding `-Zsave-analysis` flag has been removed from the compiler as well.
1497- [Unaligned references to packed fields are now a hard error.](https://github.com/rust-lang/rust/pull/102513/) This has been a warning since 1.53, and denied by default with a future-compatibility warning since 1.62.
1498- [Update the minimum external LLVM to 14.](https://github.com/rust-lang/rust/pull/107573/)
1499- [Cargo now emits errors on invalid characters in a registry token.](https://github.com/rust-lang/cargo/pull/11600/)
1500- [When `default-features` is set to false of a workspace dependency, and an inherited dependency of a member has `default-features = true`, Cargo will enable default features of that dependency.](https://github.com/rust-lang/cargo/pull/11409/)
1501- [Cargo denies `CARGO_HOME` in the `[env]` configuration table. Cargo itself doesn't pick up this value, but recursive calls to cargo would, which was not intended.](https://github.com/rust-lang/cargo/pull/11644/)
1502- [Debuginfo for build dependencies is now off if not explicitly set. This is expected to improve the overall build time.](https://github.com/rust-lang/cargo/pull/11252/)
1503- [The Rust distribution no longer always includes rustdoc](https://github.com/rust-lang/rust/pull/106886)
1504 If `tools = [...]` is set in config.toml, we will respect a missing rustdoc in that list. By
1505 default rustdoc remains included. To retain the prior behavior explicitly add `"rustdoc"` to the
1506 list.
1507
1508<a id="1.69.0-Internal-Changes"></a>
1509
1510Internal Changes
1511----------------
1512
1513These changes do not affect any public interfaces of Rust, but they represent
1514significant improvements to the performance or internals of rustc and related
1515tools.
1516
1517- [Move `format_args!()` into AST (and expand it during AST lowering)](https://github.com/rust-lang/rust/pull/106745/)
1518
1519Version 1.68.2 (2023-03-28)
1520===========================
1521
1522- [Update the GitHub RSA host key bundled within Cargo](https://github.com/rust-lang/cargo/pull/11883).
1523 The key was [rotated by GitHub](https://github.blog/2023-03-23-we-updated-our-rsa-ssh-host-key/)
1524 on 2023-03-24 after the old one leaked.
1525- [Mark the old GitHub RSA host key as revoked](https://github.com/rust-lang/cargo/pull/11889).
1526 This will prevent Cargo from accepting the leaked key even when trusted by
1527 the system.
1528- [Add support for `@revoked` and a better error message for `@cert-authority` in Cargo's SSH host key verification](https://github.com/rust-lang/cargo/pull/11635)
1529
1530Version 1.68.1 (2023-03-23)
1531===========================
1532
1533- [Fix miscompilation in produced Windows MSVC artifacts](https://github.com/rust-lang/rust/pull/109094)
1534 This was introduced by enabling ThinLTO for the distributed rustc which led
1535 to miscompilations in the resulting binary. Currently this is believed to be
1536 limited to the -Zdylib-lto flag used for rustc compilation, rather than a
1537 general bug in ThinLTO, so only rustc artifacts should be affected.
1538- [Fix --enable-local-rust builds](https://github.com/rust-lang/rust/pull/109111/)
1539- [Treat `$prefix-clang` as `clang` in linker detection code](https://github.com/rust-lang/rust/pull/109156)
1540- [Fix panic in compiler code](https://github.com/rust-lang/rust/pull/108162)
1541
1542Version 1.68.0 (2023-03-09)
1543==========================
1544
1545<a id="1.68.0-Language"></a>
1546
1547Language
1548--------
1549
1550- [Stabilize default_alloc_error_handler](https://github.com/rust-lang/rust/pull/102318/)
1551 This allows usage of `alloc` on stable without requiring the
1552 definition of a handler for allocation failure. Defining custom handlers is still unstable.
1553- [Stabilize `efiapi` calling convention.](https://github.com/rust-lang/rust/pull/105795/)
1554- [Remove implicit promotion for types with drop glue](https://github.com/rust-lang/rust/pull/105085/)
1555
1556<a id="1.68.0-Compiler"></a>
1557
1558Compiler
1559--------
1560
1561- [Change `bindings_with_variant_name` to deny-by-default](https://github.com/rust-lang/rust/pull/104154/)
1562- [Allow .. to be parsed as let initializer](https://github.com/rust-lang/rust/pull/105701/)
1563- [Add `armv7-sony-vita-newlibeabihf` as a tier 3 target](https://github.com/rust-lang/rust/pull/105712/)
1564- [Always check alignment during compile-time const evaluation](https://github.com/rust-lang/rust/pull/104616/)
1565- [Disable "split dwarf inlining" by default.](https://github.com/rust-lang/rust/pull/106709/)
1566- [Add vendor to Fuchsia's target triple](https://github.com/rust-lang/rust/pull/106429/)
1567- [Enable sanitizers for s390x-linux](https://github.com/rust-lang/rust/pull/107127/)
1568
1569<a id="1.68.0-Libraries"></a>
1570
1571Libraries
1572---------
1573
1574- [Loosen the bound on the Debug implementation of Weak.](https://github.com/rust-lang/rust/pull/90291/)
1575- [Make `std::task::Context` !Send and !Sync](https://github.com/rust-lang/rust/pull/95985/)
1576- [PhantomData layout guarantees](https://github.com/rust-lang/rust/pull/104081/)
1577- [Don't derive Debug for `OnceWith` & `RepeatWith`](https://github.com/rust-lang/rust/pull/104163/)
1578- [Implement DerefMut for PathBuf](https://github.com/rust-lang/rust/pull/105018/)
1579- [Add O(1) `Vec -> VecDeque` conversion guarantee](https://github.com/rust-lang/rust/pull/105128/)
1580- [Leak amplification for peek_mut() to ensure BinaryHeap's invariant is always met](https://github.com/rust-lang/rust/pull/105851/)
1581
1582<a id="1.68.0-Stabilized-APIs"></a>
1583
1584Stabilized APIs
1585---------------
1586
1587- [`{core,std}::pin::pin!`](https://doc.rust-lang.org/stable/std/pin/macro.pin.html)
1588- [`impl From<bool> for {f32,f64}`](https://doc.rust-lang.org/stable/std/primitive.f32.html#impl-From%3Cbool%3E-for-f32)
1589- [`std::path::MAIN_SEPARATOR_STR`](https://doc.rust-lang.org/stable/std/path/constant.MAIN_SEPARATOR_STR.html)
1590- [`impl DerefMut for PathBuf`](https://doc.rust-lang.org/stable/std/path/struct.PathBuf.html#impl-DerefMut-for-PathBuf)
1591
1592These APIs are now stable in const contexts:
1593
1594- [`VecDeque::new`](https://doc.rust-lang.org/stable/std/collections/struct.VecDeque.html#method.new)
1595
1596<a id="1.68.0-Cargo"></a>
1597
1598Cargo
1599-----
1600
1601- [Stabilize sparse registry support for crates.io](https://github.com/rust-lang/cargo/pull/11224/)
1602- [`cargo build --verbose` tells you more about why it recompiles.](https://github.com/rust-lang/cargo/pull/11407/)
1603- [Show progress of crates.io index update even `net.git-fetch-with-cli` option enabled](https://github.com/rust-lang/cargo/pull/11579/)
1604
1605<a id="1.68.0-Misc"></a>
1606
1607Misc
1608----
1609
1610<a id="1.68.0-Compatibility-Notes"></a>
1611
1612Compatibility Notes
1613-------------------
1614
1615- [Only support Android NDK 25 or newer](https://blog.rust-lang.org/2023/01/09/android-ndk-update-r25.html)
1616- [Add `SEMICOLON_IN_EXPRESSIONS_FROM_MACROS` to future-incompat report](https://github.com/rust-lang/rust/pull/103418/)
1617- [Only specify `--target` by default for `-Zgcc-ld=lld` on wasm](https://github.com/rust-lang/rust/pull/101792/)
1618- [Bump `IMPLIED_BOUNDS_ENTAILMENT` to Deny + ReportNow](https://github.com/rust-lang/rust/pull/106465/)
1619- [`std::task::Context` no longer implements Send and Sync](https://github.com/rust-lang/rust/pull/95985)
1620
1621<a id="1.68.0-Internal-Changes"></a>
1622
1623Internal Changes
1624----------------
1625
1626These changes do not affect any public interfaces of Rust, but they represent
1627significant improvements to the performance or internals of rustc and related
1628tools.
1629
1630- [Encode spans relative to the enclosing item](https://github.com/rust-lang/rust/pull/84762/)
1631- [Don't normalize in AstConv](https://github.com/rust-lang/rust/pull/101947/)
1632- [Find the right lower bound region in the scenario of partial order relations](https://github.com/rust-lang/rust/pull/104765/)
1633- [Fix impl block in const expr](https://github.com/rust-lang/rust/pull/104889/)
1634- [Check ADT fields for copy implementations considering regions](https://github.com/rust-lang/rust/pull/105102/)
1635- [rustdoc: simplify JS search routine by not messing with lev distance](https://github.com/rust-lang/rust/pull/105796/)
1636- [Enable ThinLTO for rustc on `x86_64-pc-windows-msvc`](https://github.com/rust-lang/rust/pull/103591/)
1637- [Enable ThinLTO for rustc on `x86_64-apple-darwin`](https://github.com/rust-lang/rust/pull/103647/)
1638
1639Version 1.67.1 (2023-02-09)
1640===========================
1641
1642- [Fix interoperability with thin archives.](https://github.com/rust-lang/rust/pull/107360)
1643- [Fix an internal error in the compiler build process.](https://github.com/rust-lang/rust/pull/105624)
1644- [Downgrade `clippy::uninlined_format_args` to pedantic.](https://github.com/rust-lang/rust-clippy/pull/10265)
1645
1646Version 1.67.0 (2023-01-26)
1647==========================
1648
1649<a id="1.67.0-Language"></a>
1650
1651Language
1652--------
1653
1654- [Make `Sized` predicates coinductive, allowing cycles.](https://github.com/rust-lang/rust/pull/100386/)
1655- [`#[must_use]` annotations on `async fn` also affect the `Future::Output`.](https://github.com/rust-lang/rust/pull/100633/)
1656- [Elaborate supertrait obligations when deducing closure signatures.](https://github.com/rust-lang/rust/pull/101834/)
1657- [Invalid literals are no longer an error under `cfg(FALSE)`.](https://github.com/rust-lang/rust/pull/102944/)
1658- [Unreserve braced enum variants in value namespace.](https://github.com/rust-lang/rust/pull/103578/)
1659
1660<a id="1.67.0-Compiler"></a>
1661
1662Compiler
1663--------
1664
1665- [Enable varargs support for calling conventions other than `C` or `cdecl`.](https://github.com/rust-lang/rust/pull/97971/)
1666- [Add new MIR constant propagation based on dataflow analysis.](https://github.com/rust-lang/rust/pull/101168/)
1667- [Optimize field ordering by grouping m\*2^n-sized fields with equivalently aligned ones.](https://github.com/rust-lang/rust/pull/102750/)
1668- [Stabilize native library modifier `verbatim`.](https://github.com/rust-lang/rust/pull/104360/)
1669
1670Added, updated, and removed targets:
1671
1672- [Add a tier 3 target for PowerPC on AIX](https://github.com/rust-lang/rust/pull/102293/), `powerpc64-ibm-aix`.
1673- [Add a tier 3 target for the Sony PlayStation 1](https://github.com/rust-lang/rust/pull/102689/), `mipsel-sony-psx`.
1674- [Add tier 3 `no_std` targets for the QNX Neutrino RTOS](https://github.com/rust-lang/rust/pull/102701/),
1675 `aarch64-unknown-nto-qnx710` and `x86_64-pc-nto-qnx710`.
1676- [Promote UEFI targets to tier 2](https://github.com/rust-lang/rust/pull/103933/), `aarch64-unknown-uefi`, `i686-unknown-uefi`, and `x86_64-unknown-uefi`.
1677- [Remove tier 3 `linuxkernel` targets](https://github.com/rust-lang/rust/pull/104015/) (not used by the actual kernel).
1678
1679Refer to Rust's [platform support page][platform-support-doc]
1680for more information on Rust's tiered platform support.
1681
1682<a id="1.67.0-Libraries"></a>
1683
1684Libraries
1685---------
1686
1687- [Merge `crossbeam-channel` into `std::sync::mpsc`.](https://github.com/rust-lang/rust/pull/93563/)
1688- [Fix inconsistent rounding of 0.5 when formatted to 0 decimal places.](https://github.com/rust-lang/rust/pull/102935/)
1689- [Derive `Eq` and `Hash` for `ControlFlow`.](https://github.com/rust-lang/rust/pull/103084/)
1690- [Don't build `compiler_builtins` with `-C panic=abort`.](https://github.com/rust-lang/rust/pull/103786/)
1691
1692<a id="1.67.0-Stabilized-APIs"></a>
1693
1694Stabilized APIs
1695---------------
1696
1697- [`{integer}::checked_ilog`](https://doc.rust-lang.org/stable/std/primitive.i32.html#method.checked_ilog)
1698- [`{integer}::checked_ilog2`](https://doc.rust-lang.org/stable/std/primitive.i32.html#method.checked_ilog2)
1699- [`{integer}::checked_ilog10`](https://doc.rust-lang.org/stable/std/primitive.i32.html#method.checked_ilog10)
1700- [`{integer}::ilog`](https://doc.rust-lang.org/stable/std/primitive.i32.html#method.ilog)
1701- [`{integer}::ilog2`](https://doc.rust-lang.org/stable/std/primitive.i32.html#method.ilog2)
1702- [`{integer}::ilog10`](https://doc.rust-lang.org/stable/std/primitive.i32.html#method.ilog10)
1703- [`NonZeroU*::ilog2`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroU32.html#method.ilog2)
1704- [`NonZeroU*::ilog10`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroU32.html#method.ilog10)
1705- [`NonZero*::BITS`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroU32.html#associatedconstant.BITS)
1706
1707These APIs are now stable in const contexts:
1708
1709- [`char::from_u32`](https://doc.rust-lang.org/stable/std/primitive.char.html#method.from_u32)
1710- [`char::from_digit`](https://doc.rust-lang.org/stable/std/primitive.char.html#method.from_digit)
1711- [`char::to_digit`](https://doc.rust-lang.org/stable/std/primitive.char.html#method.to_digit)
1712- [`core::char::from_u32`](https://doc.rust-lang.org/stable/core/char/fn.from_u32.html)
1713- [`core::char::from_digit`](https://doc.rust-lang.org/stable/core/char/fn.from_digit.html)
1714
1715<a id="1.67.0-Compatibility-Notes"></a>
1716
1717Compatibility Notes
1718-------------------
1719
1720- [The layout of `repr(Rust)` types now groups m\*2^n-sized fields with
1721 equivalently aligned ones.](https://github.com/rust-lang/rust/pull/102750/)
1722 This is intended to be an optimization, but it is also known to increase type
1723 sizes in a few cases for the placement of enum tags. As a reminder, the layout
1724 of `repr(Rust)` types is an implementation detail, subject to change.
1725- [0.5 now rounds to 0 when formatted to 0 decimal places.](https://github.com/rust-lang/rust/pull/102935/)
1726 This makes it consistent with the rest of floating point formatting that
1727 rounds ties toward even digits.
1728- [Chains of `&&` and `||` will now drop temporaries from their sub-expressions in
1729 evaluation order, left-to-right.](https://github.com/rust-lang/rust/pull/103293/)
1730 Previously, it was "twisted" such that the _first_ expression dropped its
1731 temporaries _last_, after all of the other expressions dropped in order.
1732- [Underscore suffixes on string literals are now a hard error.](https://github.com/rust-lang/rust/pull/103914/)
1733 This has been a future-compatibility warning since 1.20.0.
1734- [Stop passing `-export-dynamic` to `wasm-ld`.](https://github.com/rust-lang/rust/pull/105405/)
1735- [`main` is now mangled as `__main_void` on `wasm32-wasi`.](https://github.com/rust-lang/rust/pull/105468/)
1736- [Cargo now emits an error if there are multiple registries in the configuration
1737 with the same index URL.](https://github.com/rust-lang/cargo/pull/10592)
1738
1739<a id="1.67.0-Internal-Changes"></a>
1740
1741Internal Changes
1742----------------
1743
1744These changes do not affect any public interfaces of Rust, but they represent
1745significant improvements to the performance or internals of rustc and related
1746tools.
1747
1748- [Rewrite LLVM's archive writer in Rust.](https://github.com/rust-lang/rust/pull/97485/)
1749
1750Version 1.66.1 (2023-01-10)
1751===========================
1752
1753- Added validation of SSH host keys for git URLs in Cargo ([CVE-2022-46176](https://www.cve.org/CVERecord?id=CVE-2022-46176))
1754
1755Version 1.66.0 (2022-12-15)
1756==========================
1757
1758Language
1759--------
1760- [Permit specifying explicit discriminants on all `repr(Int)` enums](https://github.com/rust-lang/rust/pull/95710/)
1761 ```rust
1762 #[repr(u8)]
1763 enum Foo {
1764 A(u8) = 0,
1765 B(i8) = 1,
1766 C(bool) = 42,
1767 }
1768 ```
1769- [Allow transmutes between the same type differing only in lifetimes](https://github.com/rust-lang/rust/pull/101520/)
1770- [Change constant evaluation errors from a deny-by-default lint to a hard error](https://github.com/rust-lang/rust/pull/102091/)
1771- [Trigger `must_use` on `impl Trait` for supertraits](https://github.com/rust-lang/rust/pull/102287/)
1772 This makes `impl ExactSizeIterator` respect the existing `#[must_use]` annotation on `Iterator`.
1773- [Allow `..=X` in patterns](https://github.com/rust-lang/rust/pull/102275/)
1774- [Uplift `clippy::for_loops_over_fallibles` lint into rustc](https://github.com/rust-lang/rust/pull/99696/)
1775- [Stabilize `sym` operands in inline assembly](https://github.com/rust-lang/rust/pull/103168/)
1776- [Update to Unicode 15](https://github.com/rust-lang/rust/pull/101912/)
1777- [Opaque types no longer imply lifetime bounds](https://github.com/rust-lang/rust/pull/95474/)
1778 This is a soundness fix which may break code that was erroneously relying on this behavior.
1779
1780Compiler
1781--------
1782- [Add armv5te-none-eabi and thumbv5te-none-eabi tier 3 targets](https://github.com/rust-lang/rust/pull/101329/)
1783 - Refer to Rust's [platform support page][platform-support-doc] for more
1784 information on Rust's tiered platform support.
1785- [Add support for linking against macOS universal libraries](https://github.com/rust-lang/rust/pull/98736)
1786
1787Libraries
1788---------
1789- [Fix `#[derive(Default)]` on a generic `#[default]` enum adding unnecessary `Default` bounds](https://github.com/rust-lang/rust/pull/101040/)
1790- [Update to Unicode 15](https://github.com/rust-lang/rust/pull/101821/)
1791
1792Stabilized APIs
1793---------------
1794
1795- [`proc_macro::Span::source_text`](https://doc.rust-lang.org/stable/proc_macro/struct.Span.html#method.source_text)
1796- [`uX::{checked_add_signed, overflowing_add_signed, saturating_add_signed, wrapping_add_signed}`](https://doc.rust-lang.org/stable/std/primitive.u8.html#method.checked_add_signed)
1797- [`iX::{checked_add_unsigned, overflowing_add_unsigned, saturating_add_unsigned, wrapping_add_unsigned}`](https://doc.rust-lang.org/stable/std/primitive.i8.html#method.checked_add_unsigned)
1798- [`iX::{checked_sub_unsigned, overflowing_sub_unsigned, saturating_sub_unsigned, wrapping_sub_unsigned}`](https://doc.rust-lang.org/stable/std/primitive.i8.html#method.checked_sub_unsigned)
1799- [`BTreeSet::{first, last, pop_first, pop_last}`](https://doc.rust-lang.org/stable/std/collections/struct.BTreeSet.html#method.first)
1800- [`BTreeMap::{first_key_value, last_key_value, first_entry, last_entry, pop_first, pop_last}`](https://doc.rust-lang.org/stable/std/collections/struct.BTreeMap.html#method.first_key_value)
1801- [Add `AsFd` implementations for stdio lock types on WASI.](https://github.com/rust-lang/rust/pull/101768/)
1802- [`impl TryFrom<Vec<T>> for Box<[T; N]>`](https://doc.rust-lang.org/stable/std/boxed/struct.Box.html#impl-TryFrom%3CVec%3CT%2C%20Global%3E%3E-for-Box%3C%5BT%3B%20N%5D%2C%20Global%3E)
1803- [`core::hint::black_box`](https://doc.rust-lang.org/stable/std/hint/fn.black_box.html)
1804- [`Duration::try_from_secs_{f32,f64}`](https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.try_from_secs_f32)
1805- [`Option::unzip`](https://doc.rust-lang.org/stable/std/option/enum.Option.html#method.unzip)
1806- [`std::os::fd`](https://doc.rust-lang.org/stable/std/os/fd/index.html)
1807
1808
1809Rustdoc
1810-------
1811
1812- [Add Rustdoc warning for invalid HTML tags in the documentation](https://github.com/rust-lang/rust/pull/101720/)
1813
1814Cargo
1815-----
1816
1817- [Added `cargo remove` to remove dependencies from Cargo.toml](https://doc.rust-lang.org/nightly/cargo/commands/cargo-remove.html)
1818- [`cargo publish` now waits for the new version to be downloadable before exiting](https://github.com/rust-lang/cargo/pull/11062)
1819
1820See [detailed release notes](https://github.com/rust-lang/cargo/blob/master/CHANGELOG.md#cargo-166-2022-12-15) for more.
1821
1822Compatibility Notes
1823-------------------
1824
1825- [Only apply `ProceduralMasquerade` hack to older versions of `rental`](https://github.com/rust-lang/rust/pull/94063/)
1826- [Don't export `__heap_base` and `__data_end` on wasm32-wasi.](https://github.com/rust-lang/rust/pull/102385/)
1827- [Don't export `__wasm_init_memory` on WebAssembly.](https://github.com/rust-lang/rust/pull/102426/)
1828- [Only export `__tls_*` on wasm32-unknown-unknown.](https://github.com/rust-lang/rust/pull/102440/)
1829- [Don't link to `libresolv` in libstd on Darwin](https://github.com/rust-lang/rust/pull/102766/)
1830- [Update libstd's libc to 0.2.135 (to make `libstd` no longer pull in `libiconv.dylib` on Darwin)](https://github.com/rust-lang/rust/pull/103277/)
1831- [Opaque types no longer imply lifetime bounds](https://github.com/rust-lang/rust/pull/95474/)
1832 This is a soundness fix which may break code that was erroneously relying on this behavior.
1833- [Make `order_dependent_trait_objects` show up in future-breakage reports](https://github.com/rust-lang/rust/pull/102635/)
1834- [Change std::process::Command spawning to default to inheriting the parent's signal mask](https://github.com/rust-lang/rust/pull/101077/)
1835
1836Internal Changes
1837----------------
1838
1839These changes do not affect any public interfaces of Rust, but they represent
1840significant improvements to the performance or internals of rustc and related
1841tools.
1842
1843- [Enable BOLT for LLVM compilation](https://github.com/rust-lang/rust/pull/94381/)
1844- [Enable LTO for rustc_driver.so](https://github.com/rust-lang/rust/pull/101403/)
1845
1846Version 1.65.0 (2022-11-03)
1847==========================
1848
1849Language
1850--------
1851- [Error on `as` casts of enums with `#[non_exhaustive]` variants](https://github.com/rust-lang/rust/pull/92744/)
1852- [Stabilize `let else`](https://github.com/rust-lang/rust/pull/93628/)
1853- [Stabilize generic associated types (GATs)](https://github.com/rust-lang/rust/pull/96709/)
1854- [Add lints `let_underscore_drop` and `let_underscore_lock` from Clippy](https://github.com/rust-lang/rust/pull/97739/)
1855- [Stabilize `break`ing from arbitrary labeled blocks ("label-break-value")](https://github.com/rust-lang/rust/pull/99332/)
1856- [Uninitialized integers, floats, and raw pointers are now considered immediate UB](https://github.com/rust-lang/rust/pull/98919/).
1857 Usage of `MaybeUninit` is the correct way to work with uninitialized memory.
1858- [Stabilize raw-dylib for Windows x86_64, aarch64, and thumbv7a](https://github.com/rust-lang/rust/pull/99916/)
1859- [Do not allow `Drop` impl on foreign ADTs](https://github.com/rust-lang/rust/pull/99576/)
1860
1861Compiler
1862--------
1863- [Stabilize -Csplit-debuginfo on Linux](https://github.com/rust-lang/rust/pull/98051/)
1864- [Use niche-filling optimization even when multiple variants have data](https://github.com/rust-lang/rust/pull/94075/)
1865- [Associated type projections are now verified to be well-formed prior to resolving the underlying type](https://github.com/rust-lang/rust/pull/99217/#issuecomment-1209365630)
1866- [Stringify non-shorthand visibility correctly](https://github.com/rust-lang/rust/pull/100350/)
1867- [Normalize struct field types when unsizing](https://github.com/rust-lang/rust/pull/101831/)
1868- [Update to LLVM 15](https://github.com/rust-lang/rust/pull/99464/)
1869- [Fix aarch64 call abi to correctly zeroext when needed](https://github.com/rust-lang/rust/pull/97800/)
1870- [debuginfo: Generalize C++-like encoding for enums](https://github.com/rust-lang/rust/pull/98393/)
1871- [Add `special_module_name` lint](https://github.com/rust-lang/rust/pull/94467/)
1872- [Add support for generating unique profraw files by default when using `-C instrument-coverage`](https://github.com/rust-lang/rust/pull/100384/)
1873- [Allow dynamic linking for iOS/tvOS targets](https://github.com/rust-lang/rust/pull/100636/)
1874
1875New targets:
1876
1877- [Add armv4t-none-eabi as a tier 3 target](https://github.com/rust-lang/rust/pull/100244/)
1878- [Add powerpc64-unknown-openbsd and riscv64-unknown-openbsd as tier 3 targets](https://github.com/rust-lang/rust/pull/101025/)
1879 - Refer to Rust's [platform support page][platform-support-doc] for more
1880 information on Rust's tiered platform support.
1881
1882Libraries
1883---------
1884
1885- [Don't generate `PartialEq::ne` in derive(PartialEq)](https://github.com/rust-lang/rust/pull/98655/)
1886- [Windows RNG: Use `BCRYPT_RNG_ALG_HANDLE` by default](https://github.com/rust-lang/rust/pull/101325/)
1887- [Forbid mixing `System` with direct system allocator calls](https://github.com/rust-lang/rust/pull/101394/)
1888- [Document no support for writing to non-blocking stdio/stderr](https://github.com/rust-lang/rust/pull/101416/)
1889- [`std::layout::Layout` size must not overflow `isize::MAX` when rounded up to `align`](https://github.com/rust-lang/rust/pull/95295)
1890 This also changes the safety conditions on `Layout::from_size_align_unchecked`.
1891
1892Stabilized APIs
1893---------------
1894
1895- [`std::backtrace::Backtrace`](https://doc.rust-lang.org/stable/std/backtrace/struct.Backtrace.html)
1896- [`Bound::as_ref`](https://doc.rust-lang.org/stable/std/ops/enum.Bound.html#method.as_ref)
1897- [`std::io::read_to_string`](https://doc.rust-lang.org/stable/std/io/fn.read_to_string.html)
1898- [`<*const T>::cast_mut`](https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.cast_mut)
1899- [`<*mut T>::cast_const`](https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.cast_const)
1900
1901These APIs are now stable in const contexts:
1902
1903- [`<*const T>::offset_from`](https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.offset_from)
1904- [`<*mut T>::offset_from`](https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.offset_from)
1905
1906Cargo
1907-----
1908
1909- [Apply GitHub fast path even for partial hashes](https://github.com/rust-lang/cargo/pull/10807/)
1910- [Do not add home bin path to PATH if it's already there](https://github.com/rust-lang/cargo/pull/11023/)
1911- [Take priority into account within the pending queue](https://github.com/rust-lang/cargo/pull/11032/).
1912 This slightly optimizes job scheduling by Cargo, with typically small improvements on larger crate graph builds.
1913
1914Compatibility Notes
1915-------------------
1916
1917- [`std::layout::Layout` size must not overflow `isize::MAX` when rounded up to `align`](https://github.com/rust-lang/rust/pull/95295).
1918 This also changes the safety conditions on `Layout::from_size_align_unchecked`.
1919- [`PollFn` now only implements `Unpin` if the closure is `Unpin`](https://github.com/rust-lang/rust/pull/102737).
1920 This is a possible breaking change if users were relying on the blanket unpin implementation.
1921 See discussion on the PR for details of why this change was made.
1922- [Drop ExactSizeIterator impl from std::char::EscapeAscii](https://github.com/rust-lang/rust/pull/99880)
1923 This is a backwards-incompatible change to the standard library's surface
1924 area, but is unlikely to affect real world usage.
1925- [Do not consider a single repeated lifetime eligible for elision in the return type](https://github.com/rust-lang/rust/pull/103450)
1926 This behavior was unintentionally changed in 1.64.0, and this release reverts that change by making this an error again.
1927- [Reenable disabled early syntax gates as future-incompatibility lints](https://github.com/rust-lang/rust/pull/99935/)
1928- [Update the minimum external LLVM to 13](https://github.com/rust-lang/rust/pull/100460/)
1929- [Don't duplicate file descriptors into stdio fds](https://github.com/rust-lang/rust/pull/101426/)
1930- [Sunset RLS](https://github.com/rust-lang/rust/pull/100863/)
1931- [Deny usage of `#![cfg_attr(..., crate_type = ...)]` to set the crate type](https://github.com/rust-lang/rust/pull/99784/)
1932 This strengthens the forward compatibility lint deprecated_cfg_attr_crate_type_name to deny.
1933- [`llvm-has-rust-patches` allows setting the build system to treat the LLVM as having Rust-specific patches](https://github.com/rust-lang/rust/pull/101072)
1934 This option may need to be set for distributions that are building Rust with a patched LLVM via `llvm-config`, not the built-in LLVM.
1935- Combining three or more languages (e.g. Objective C, C++ and Rust) into one binary may hit linker limitations when using `lld`. For more information, see [issue 102754][102754].
1936
1937[102754]: https://github.com/rust-lang/rust/issues/102754
1938
1939Internal Changes
1940----------------
1941
1942These changes do not affect any public interfaces of Rust, but they represent
1943significant improvements to the performance or internals of rustc and related
1944tools.
1945
1946- [Add `x.sh` and `x.ps1` shell scripts](https://github.com/rust-lang/rust/pull/99992/)
1947- [compiletest: use target cfg instead of hard-coded tables](https://github.com/rust-lang/rust/pull/100260/)
1948- [Use object instead of LLVM for reading bitcode from rlibs](https://github.com/rust-lang/rust/pull/98100/)
1949- [Enable MIR inlining for optimized compilations](https://github.com/rust-lang/rust/pull/91743)
1950 This provides a 3-10% improvement in compiletimes for real world crates. See [perf results](https://perf.rust-lang.org/compare.html?start=aedf78e56b2279cc869962feac5153b6ba7001ed&end=0075bb4fad68e64b6d1be06bf2db366c30bc75e1&stat=instructions:u).
1951
1952Version 1.64.0 (2022-09-22)
1953===========================
1954
1955Language
1956--------
1957- [Unions with mutable references or tuples of allowed types are now allowed](https://github.com/rust-lang/rust/pull/97995/)
1958- It is now considered valid to deallocate memory pointed to by a shared reference `&T` [if every byte in `T` is inside an `UnsafeCell`](https://github.com/rust-lang/rust/pull/98017/)
1959- Unused tuple struct fields are now warned against in an allow-by-default lint, [`unused_tuple_struct_fields`](https://github.com/rust-lang/rust/pull/95977/), similar to the existing warning for unused struct fields. This lint will become warn-by-default in the future.
1960
1961Compiler
1962--------
1963- [Add Nintendo Switch as tier 3 target](https://github.com/rust-lang/rust/pull/88991/)
1964 - Refer to Rust's [platform support page][platform-support-doc] for more
1965 information on Rust's tiered platform support.
1966- [Only compile `#[used]` as llvm.compiler.used for ELF targets](https://github.com/rust-lang/rust/pull/93718/)
1967- [Add the `--diagnostic-width` compiler flag to define the terminal width.](https://github.com/rust-lang/rust/pull/95635/)
1968- [Add support for link-flavor `rust-lld` for iOS, tvOS and watchOS](https://github.com/rust-lang/rust/pull/98771/)
1969
1970Libraries
1971---------
1972- [Remove restrictions on compare-exchange memory ordering.](https://github.com/rust-lang/rust/pull/98383/)
1973- You can now `write!` or `writeln!` into an `OsString`: [Implement `fmt::Write` for `OsString`](https://github.com/rust-lang/rust/pull/97915/)
1974- [Make RwLockReadGuard covariant](https://github.com/rust-lang/rust/pull/96820/)
1975- [Implement `FusedIterator` for `std::net::[Into]Incoming`](https://github.com/rust-lang/rust/pull/97300/)
1976- [`impl<T: AsRawFd> AsRawFd for {Arc,Box}<T>`](https://github.com/rust-lang/rust/pull/97437/)
1977- [`ptr::copy` and `ptr::swap` are doing untyped copies](https://github.com/rust-lang/rust/pull/97712/)
1978- [Add cgroupv1 support to `available_parallelism`](https://github.com/rust-lang/rust/pull/97925/)
1979- [Mitigate many incorrect uses of `mem::uninitialized`](https://github.com/rust-lang/rust/pull/99182/)
1980
1981Stabilized APIs
1982---------------
1983
1984- [`future::IntoFuture`](https://doc.rust-lang.org/stable/std/future/trait.IntoFuture.html)
1985- [`future::poll_fn`](https://doc.rust-lang.org/stable/std/future/fn.poll_fn.html)
1986- [`task::ready!`](https://doc.rust-lang.org/stable/std/task/macro.ready.html)
1987- [`num::NonZero*::checked_mul`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroUsize.html#method.checked_mul)
1988- [`num::NonZero*::checked_pow`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroUsize.html#method.checked_pow)
1989- [`num::NonZero*::saturating_mul`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroUsize.html#method.saturating_mul)
1990- [`num::NonZero*::saturating_pow`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroUsize.html#method.saturating_pow)
1991- [`num::NonZeroI*::abs`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroIsize.html#method.abs)
1992- [`num::NonZeroI*::checked_abs`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroIsize.html#method.checked_abs)
1993- [`num::NonZeroI*::overflowing_abs`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroIsize.html#method.overflowing_abs)
1994- [`num::NonZeroI*::saturating_abs`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroIsize.html#method.saturating_abs)
1995- [`num::NonZeroI*::unsigned_abs`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroIsize.html#method.unsigned_abs)
1996- [`num::NonZeroI*::wrapping_abs`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroIsize.html#method.wrapping_abs)
1997- [`num::NonZeroU*::checked_add`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroUsize.html#method.checked_add)
1998- [`num::NonZeroU*::checked_next_power_of_two`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroUsize.html#method.checked_next_power_of_two)
1999- [`num::NonZeroU*::saturating_add`](https://doc.rust-lang.org/stable/std/num/struct.NonZeroUsize.html#method.saturating_add)
2000- [`os::unix::process::CommandExt::process_group`](https://doc.rust-lang.org/stable/std/os/unix/process/trait.CommandExt.html#tymethod.process_group)
2001- [`os::windows::fs::FileTypeExt::is_symlink_dir`](https://doc.rust-lang.org/stable/std/os/windows/fs/trait.FileTypeExt.html#tymethod.is_symlink_dir)
2002- [`os::windows::fs::FileTypeExt::is_symlink_file`](https://doc.rust-lang.org/stable/std/os/windows/fs/trait.FileTypeExt.html#tymethod.is_symlink_file)
2003
2004These types were previously stable in `std::ffi`, but are now also available in `core` and `alloc`:
2005
2006- [`core::ffi::CStr`](https://doc.rust-lang.org/stable/core/ffi/struct.CStr.html)
2007- [`core::ffi::FromBytesWithNulError`](https://doc.rust-lang.org/stable/core/ffi/struct.FromBytesWithNulError.html)
2008- [`alloc::ffi::CString`](https://doc.rust-lang.org/stable/alloc/ffi/struct.CString.html)
2009- [`alloc::ffi::FromVecWithNulError`](https://doc.rust-lang.org/stable/alloc/ffi/struct.FromVecWithNulError.html)
2010- [`alloc::ffi::IntoStringError`](https://doc.rust-lang.org/stable/alloc/ffi/struct.IntoStringError.html)
2011- [`alloc::ffi::NulError`](https://doc.rust-lang.org/stable/alloc/ffi/struct.NulError.html)
2012
2013These types were previously stable in `std::os::raw`, but are now also available in `core::ffi` and `std::ffi`:
2014
2015- [`ffi::c_char`](https://doc.rust-lang.org/stable/std/ffi/type.c_char.html)
2016- [`ffi::c_double`](https://doc.rust-lang.org/stable/std/ffi/type.c_double.html)
2017- [`ffi::c_float`](https://doc.rust-lang.org/stable/std/ffi/type.c_float.html)
2018- [`ffi::c_int`](https://doc.rust-lang.org/stable/std/ffi/type.c_int.html)
2019- [`ffi::c_long`](https://doc.rust-lang.org/stable/std/ffi/type.c_long.html)
2020- [`ffi::c_longlong`](https://doc.rust-lang.org/stable/std/ffi/type.c_longlong.html)
2021- [`ffi::c_schar`](https://doc.rust-lang.org/stable/std/ffi/type.c_schar.html)
2022- [`ffi::c_short`](https://doc.rust-lang.org/stable/std/ffi/type.c_short.html)
2023- [`ffi::c_uchar`](https://doc.rust-lang.org/stable/std/ffi/type.c_uchar.html)
2024- [`ffi::c_uint`](https://doc.rust-lang.org/stable/std/ffi/type.c_uint.html)
2025- [`ffi::c_ulong`](https://doc.rust-lang.org/stable/std/ffi/type.c_ulong.html)
2026- [`ffi::c_ulonglong`](https://doc.rust-lang.org/stable/std/ffi/type.c_ulonglong.html)
2027- [`ffi::c_ushort`](https://doc.rust-lang.org/stable/std/ffi/type.c_ushort.html)
2028
2029These APIs are now usable in const contexts:
2030
2031- [`slice::from_raw_parts`](https://doc.rust-lang.org/stable/core/slice/fn.from_raw_parts.html)
2032
2033Cargo
2034-----
2035- [Packages can now inherit settings from the workspace so that the settings
2036 can be centralized in one place.](https://github.com/rust-lang/cargo/pull/10859) See
2037 [`workspace.package`](https://doc.rust-lang.org/nightly/cargo/reference/workspaces.html#the-workspacepackage-table)
2038 and
2039 [`workspace.dependencies`](https://doc.rust-lang.org/nightly/cargo/reference/workspaces.html#the-workspacedependencies-table)
2040 for more details on how to define these common settings.
2041- [Cargo commands can now accept multiple `--target` flags to build for
2042 multiple targets at once](https://github.com/rust-lang/cargo/pull/10766), and the
2043 [`build.target`](https://doc.rust-lang.org/nightly/cargo/reference/config.html#buildtarget)
2044 config option may now take an array of multiple targets.
2045- [The `--jobs` argument can now take a negative number to count backwards from
2046 the max CPUs.](https://github.com/rust-lang/cargo/pull/10844)
2047- [`cargo add` will now update `Cargo.lock`.](https://github.com/rust-lang/cargo/pull/10902)
2048- [Added](https://github.com/rust-lang/cargo/pull/10838) the
2049 [`--crate-type`](https://doc.rust-lang.org/nightly/cargo/commands/cargo-rustc.html#option-cargo-rustc---crate-type)
2050 flag to `cargo rustc` to override the crate type.
2051- [Significantly improved the performance fetching git dependencies from GitHub
2052 when using a hash in the `rev` field.](https://github.com/rust-lang/cargo/pull/10079)
2053
2054Misc
2055----
2056- [The `rust-analyzer` rustup component is now available on the stable channel.](https://github.com/rust-lang/rust/pull/98640/)
2057
2058Compatibility Notes
2059-------------------
2060- The minimum required versions for all `-linux-gnu` targets are now at least kernel 3.2 and glibc 2.17, for targets that previously supported older versions: [Increase the minimum linux-gnu versions](https://github.com/rust-lang/rust/pull/95026/)
2061- [Network primitives are now implemented with the ideal Rust layout, not the C system layout](https://github.com/rust-lang/rust/pull/78802/). This can cause problems when transmuting the types.
2062- [Add assertion that `transmute_copy`'s `U` is not larger than `T`](https://github.com/rust-lang/rust/pull/98839/)
2063- [A soundness bug in `BTreeMap` was fixed](https://github.com/rust-lang/rust/pull/99413/) that allowed data it was borrowing to be dropped before the container.
2064- [The Drop behavior of C-like enums cast to ints has changed](https://github.com/rust-lang/rust/pull/96862/). These are already discouraged by a compiler warning.
2065- [Relate late-bound closure lifetimes to parent fn in NLL](https://github.com/rust-lang/rust/pull/98835/)
2066- [Errors at const-eval time are now in future incompatibility reports](https://github.com/rust-lang/rust/pull/97743/)
2067- On the `thumbv6m-none-eabi` target, some incorrect `asm!` statements were erroneously accepted if they used the high registers (r8 to r14) as an input/output operand. [This is no longer accepted](https://github.com/rust-lang/rust/pull/99155/).
2068- [`impl Trait` was accidentally accepted as the associated type value of return-position `impl Trait`](https://github.com/rust-lang/rust/pull/97346/), without fulfilling all the trait bounds of that associated type, as long as the hidden type satisfies said bounds. This has been fixed.
2069
2070Internal Changes
2071----------------
2072
2073These changes do not affect any public interfaces of Rust, but they represent
2074significant improvements to the performance or internals of rustc and related
2075tools.
2076
2077- Windows builds now use profile-guided optimization, providing 10-20% improvements to compiler performance: [Utilize PGO for windows x64 rustc dist builds](https://github.com/rust-lang/rust/pull/96978/)
2078- [Stop keeping metadata in memory before writing it to disk](https://github.com/rust-lang/rust/pull/96544/)
2079- [compiletest: strip debuginfo by default for mode=ui](https://github.com/rust-lang/rust/pull/98140/)
2080- Many improvements to generated code for derives, including performance improvements:
2081 - [Don't use match-destructuring for derived ops on structs.](https://github.com/rust-lang/rust/pull/98446/)
2082 - [Many small deriving cleanups](https://github.com/rust-lang/rust/pull/98741/)
2083 - [More derive output improvements](https://github.com/rust-lang/rust/pull/98758/)
2084 - [Clarify deriving code](https://github.com/rust-lang/rust/pull/98915/)
2085 - [Final derive output improvements](https://github.com/rust-lang/rust/pull/99046/)
2086 - [Stop injecting `#[allow(unused_qualifications)]` in generated `derive` implementations](https://github.com/rust-lang/rust/pull/99485/)
2087 - [Improve `derive(Debug)`](https://github.com/rust-lang/rust/pull/98190/)
2088- [Bump to clap 3](https://github.com/rust-lang/rust/pull/98213/)
2089- [fully move dropck to mir](https://github.com/rust-lang/rust/pull/98641/)
2090- [Optimize `Vec::insert` for the case where `index == len`.](https://github.com/rust-lang/rust/pull/98755/)
2091- [Convert rust-analyzer to an in-tree tool](https://github.com/rust-lang/rust/pull/99603/)
2092
2093Version 1.63.0 (2022-08-11)
2094==========================
2095
2096Language
2097--------
2098- [Remove migrate borrowck mode for pre-NLL errors.][95565]
2099- [Modify MIR building to drop repeat expressions with length zero.][95953]
2100- [Remove label/lifetime shadowing warnings.][96296]
2101- [Allow explicit generic arguments in the presence of `impl Trait` args.][96868]
2102- [Make `cenum_impl_drop_cast` warnings deny-by-default.][97652]
2103- [Prevent unwinding when `-C panic=abort` is used regardless of declared ABI.][96959]
2104- [lub: don't bail out due to empty binders.][97867]
2105
2106Compiler
2107--------
2108- [Stabilize the `bundle` native library modifier,][95818] also removing the
2109 deprecated `static-nobundle` linking kind.
2110- [Add Apple WatchOS compile targets\*.][95243]
2111- [Add a Windows application manifest to rustc-main.][96737]
2112
2113\* Refer to Rust's [platform support page][platform-support-doc] for more
2114 information on Rust's tiered platform support.
2115
2116Libraries
2117---------
2118- [Implement `Copy`, `Clone`, `PartialEq` and `Eq` for `core::fmt::Alignment`.][94530]
2119- [Extend `ptr::null` and `null_mut` to all thin (including extern) types.][94954]
2120- [`impl Read and Write for VecDeque<u8>`.][95632]
2121- [STD support for the Nintendo 3DS.][95897]
2122- [Use rounding in float to Duration conversion methods.][96051]
2123- [Make write/print macros eagerly drop temporaries.][96455]
2124- [Implement internal traits that enable `[OsStr]::join`.][96881]
2125- [Implement `Hash` for `core::alloc::Layout`.][97034]
2126- [Add capacity documentation for `OsString`.][97202]
2127- [Put a bound on collection misbehavior.][97316]
2128- [Make `std::mem::needs_drop` accept `?Sized`.][97675]
2129- [`impl Termination for Infallible` and then make the `Result` impls of `Termination` more generic.][97803]
2130- [Document Rust's stance on `/proc/self/mem`.][97837]
2131
2132Stabilized APIs
2133---------------
2134
2135- [`array::from_fn`]
2136- [`Box::into_pin`]
2137- [`BinaryHeap::try_reserve`]
2138- [`BinaryHeap::try_reserve_exact`]
2139- [`OsString::try_reserve`]
2140- [`OsString::try_reserve_exact`]
2141- [`PathBuf::try_reserve`]
2142- [`PathBuf::try_reserve_exact`]
2143- [`Path::try_exists`]
2144- [`Ref::filter_map`]
2145- [`RefMut::filter_map`]
2146- [`NonNull::<[T]>::len`][`NonNull::<slice>::len`]
2147- [`ToOwned::clone_into`]
2148- [`Ipv6Addr::to_ipv4_mapped`]
2149- [`unix::io::AsFd`]
2150- [`unix::io::BorrowedFd<'fd>`]
2151- [`unix::io::OwnedFd`]
2152- [`windows::io::AsHandle`]
2153- [`windows::io::BorrowedHandle<'handle>`]
2154- [`windows::io::OwnedHandle`]
2155- [`windows::io::HandleOrInvalid`]
2156- [`windows::io::HandleOrNull`]
2157- [`windows::io::InvalidHandleError`]
2158- [`windows::io::NullHandleError`]
2159- [`windows::io::AsSocket`]
2160- [`windows::io::BorrowedSocket<'handle>`]
2161- [`windows::io::OwnedSocket`]
2162- [`thread::scope`]
2163- [`thread::Scope`]
2164- [`thread::ScopedJoinHandle`]
2165
2166These APIs are now usable in const contexts:
2167
2168- [`array::from_ref`]
2169- [`slice::from_ref`]
2170- [`intrinsics::copy`]
2171- [`intrinsics::copy_nonoverlapping`]
2172- [`<*const T>::copy_to`]
2173- [`<*const T>::copy_to_nonoverlapping`]
2174- [`<*mut T>::copy_to`]
2175- [`<*mut T>::copy_to_nonoverlapping`]
2176- [`<*mut T>::copy_from`]
2177- [`<*mut T>::copy_from_nonoverlapping`]
2178- [`str::from_utf8`]
2179- [`Utf8Error::error_len`]
2180- [`Utf8Error::valid_up_to`]
2181- [`Condvar::new`]
2182- [`Mutex::new`]
2183- [`RwLock::new`]
2184
2185Cargo
2186-----
2187- [Stabilize the `--config path` command-line argument.][cargo/10755]
2188- [Expose rust-version in the environment as `CARGO_PKG_RUST_VERSION`.][cargo/10713]
2189
2190Compatibility Notes
2191-------------------
2192
2193- [`#[link]` attributes are now checked more strictly,][96885] which may introduce
2194 errors for invalid attribute arguments that were previously ignored.
2195- [Rounding is now used when converting a float to a `Duration`.][96051] The converted
2196 duration can differ slightly from what it was.
2197
2198Internal Changes
2199----------------
2200
2201These changes provide no direct user facing benefits, but represent significant
2202improvements to the internals and overall performance of rustc
2203and related tools.
2204
2205- [Prepare Rust for LLVM opaque pointers.][94214]
2206
2207[94214]: https://github.com/rust-lang/rust/pull/94214/
2208[94530]: https://github.com/rust-lang/rust/pull/94530/
2209[94954]: https://github.com/rust-lang/rust/pull/94954/
2210[95243]: https://github.com/rust-lang/rust/pull/95243/
2211[95565]: https://github.com/rust-lang/rust/pull/95565/
2212[95632]: https://github.com/rust-lang/rust/pull/95632/
2213[95818]: https://github.com/rust-lang/rust/pull/95818/
2214[95897]: https://github.com/rust-lang/rust/pull/95897/
2215[95953]: https://github.com/rust-lang/rust/pull/95953/
2216[96051]: https://github.com/rust-lang/rust/pull/96051/
2217[96296]: https://github.com/rust-lang/rust/pull/96296/
2218[96455]: https://github.com/rust-lang/rust/pull/96455/
2219[96737]: https://github.com/rust-lang/rust/pull/96737/
2220[96868]: https://github.com/rust-lang/rust/pull/96868/
2221[96881]: https://github.com/rust-lang/rust/pull/96881/
2222[96885]: https://github.com/rust-lang/rust/pull/96885/
2223[96959]: https://github.com/rust-lang/rust/pull/96959/
2224[97034]: https://github.com/rust-lang/rust/pull/97034/
2225[97202]: https://github.com/rust-lang/rust/pull/97202/
2226[97316]: https://github.com/rust-lang/rust/pull/97316/
2227[97652]: https://github.com/rust-lang/rust/pull/97652/
2228[97675]: https://github.com/rust-lang/rust/pull/97675/
2229[97803]: https://github.com/rust-lang/rust/pull/97803/
2230[97837]: https://github.com/rust-lang/rust/pull/97837/
2231[97867]: https://github.com/rust-lang/rust/pull/97867/
2232[cargo/10713]: https://github.com/rust-lang/cargo/pull/10713/
2233[cargo/10755]: https://github.com/rust-lang/cargo/pull/10755/
2234
2235[`array::from_fn`]: https://doc.rust-lang.org/stable/std/array/fn.from_fn.html
2236[`Box::into_pin`]: https://doc.rust-lang.org/stable/std/boxed/struct.Box.html#method.into_pin
2237[`BinaryHeap::try_reserve_exact`]: https://doc.rust-lang.org/stable/alloc/collections/binary_heap/struct.BinaryHeap.html#method.try_reserve_exact
2238[`BinaryHeap::try_reserve`]: https://doc.rust-lang.org/stable/std/collections/struct.BinaryHeap.html#method.try_reserve
2239[`OsString::try_reserve`]: https://doc.rust-lang.org/stable/std/ffi/struct.OsString.html#method.try_reserve
2240[`OsString::try_reserve_exact`]: https://doc.rust-lang.org/stable/std/ffi/struct.OsString.html#method.try_reserve_exact
2241[`PathBuf::try_reserve`]: https://doc.rust-lang.org/stable/std/path/struct.PathBuf.html#method.try_reserve
2242[`PathBuf::try_reserve_exact`]: https://doc.rust-lang.org/stable/std/path/struct.PathBuf.html#method.try_reserve_exact
2243[`Path::try_exists`]: https://doc.rust-lang.org/stable/std/path/struct.Path.html#method.try_exists
2244[`Ref::filter_map`]: https://doc.rust-lang.org/stable/std/cell/struct.Ref.html#method.filter_map
2245[`RefMut::filter_map`]: https://doc.rust-lang.org/stable/std/cell/struct.RefMut.html#method.filter_map
2246[`NonNull::<slice>::len`]: https://doc.rust-lang.org/stable/std/ptr/struct.NonNull.html#method.len
2247[`ToOwned::clone_into`]: https://doc.rust-lang.org/stable/std/borrow/trait.ToOwned.html#method.clone_into
2248[`Ipv6Addr::to_ipv4_mapped`]: https://doc.rust-lang.org/stable/std/net/struct.Ipv6Addr.html#method.to_ipv4_mapped
2249[`unix::io::AsFd`]: https://doc.rust-lang.org/stable/std/os/unix/io/trait.AsFd.html
2250[`unix::io::BorrowedFd<'fd>`]: https://doc.rust-lang.org/stable/std/os/unix/io/struct.BorrowedFd.html
2251[`unix::io::OwnedFd`]: https://doc.rust-lang.org/stable/std/os/unix/io/struct.OwnedFd.html
2252[`windows::io::AsHandle`]: https://doc.rust-lang.org/stable/std/os/windows/io/trait.AsHandle.html
2253[`windows::io::BorrowedHandle<'handle>`]: https://doc.rust-lang.org/stable/std/os/windows/io/struct.BorrowedHandle.html
2254[`windows::io::OwnedHandle`]: https://doc.rust-lang.org/stable/std/os/windows/io/struct.OwnedHandle.html
2255[`windows::io::HandleOrInvalid`]: https://doc.rust-lang.org/stable/std/os/windows/io/struct.HandleOrInvalid.html
2256[`windows::io::HandleOrNull`]: https://doc.rust-lang.org/stable/std/os/windows/io/struct.HandleOrNull.html
2257[`windows::io::InvalidHandleError`]: https://doc.rust-lang.org/stable/std/os/windows/io/struct.InvalidHandleError.html
2258[`windows::io::NullHandleError`]: https://doc.rust-lang.org/stable/std/os/windows/io/struct.NullHandleError.html
2259[`windows::io::AsSocket`]: https://doc.rust-lang.org/stable/std/os/windows/io/trait.AsSocket.html
2260[`windows::io::BorrowedSocket<'handle>`]: https://doc.rust-lang.org/stable/std/os/windows/io/struct.BorrowedSocket.html
2261[`windows::io::OwnedSocket`]: https://doc.rust-lang.org/stable/std/os/windows/io/struct.OwnedSocket.html
2262[`thread::scope`]: https://doc.rust-lang.org/stable/std/thread/fn.scope.html
2263[`thread::Scope`]: https://doc.rust-lang.org/stable/std/thread/struct.Scope.html
2264[`thread::ScopedJoinHandle`]: https://doc.rust-lang.org/stable/std/thread/struct.ScopedJoinHandle.html
2265
2266[`array::from_ref`]: https://doc.rust-lang.org/stable/std/array/fn.from_ref.html
2267[`slice::from_ref`]: https://doc.rust-lang.org/stable/std/slice/fn.from_ref.html
2268[`intrinsics::copy`]: https://doc.rust-lang.org/stable/std/intrinsics/fn.copy.html
2269[`intrinsics::copy_nonoverlapping`]: https://doc.rust-lang.org/stable/std/intrinsics/fn.copy_nonoverlapping.html
2270[`<*const T>::copy_to`]: https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.copy_to
2271[`<*const T>::copy_to_nonoverlapping`]: https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.copy_to_nonoverlapping
2272[`<*mut T>::copy_to`]: https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.copy_to-1
2273[`<*mut T>::copy_to_nonoverlapping`]: https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.copy_to_nonoverlapping-1
2274[`<*mut T>::copy_from`]: https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.copy_from
2275[`<*mut T>::copy_from_nonoverlapping`]: https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.copy_from_nonoverlapping
2276[`str::from_utf8`]: https://doc.rust-lang.org/stable/std/str/fn.from_utf8.html
2277[`Utf8Error::error_len`]: https://doc.rust-lang.org/stable/std/str/struct.Utf8Error.html#method.error_len
2278[`Utf8Error::valid_up_to`]: https://doc.rust-lang.org/stable/std/str/struct.Utf8Error.html#method.valid_up_to
2279[`Condvar::new`]: https://doc.rust-lang.org/stable/std/sync/struct.Condvar.html#method.new
2280[`Mutex::new`]: https://doc.rust-lang.org/stable/std/sync/struct.Mutex.html#method.new
2281[`RwLock::new`]: https://doc.rust-lang.org/stable/std/sync/struct.RwLock.html#method.new
2282
2283Version 1.62.1 (2022-07-19)
2284==========================
2285
2286Rust 1.62.1 addresses a few recent regressions in the compiler and standard
2287library, and also mitigates a CPU vulnerability on Intel SGX.
2288
2289* [The compiler fixed unsound function coercions involving `impl Trait` return types.][98608]
2290* [The compiler fixed an incremental compilation bug with `async fn` lifetimes.][98890]
2291* [Windows added a fallback for overlapped I/O in synchronous reads and writes.][98950]
2292* [The `x86_64-fortanix-unknown-sgx` target added a mitigation for the
2293 MMIO stale data vulnerability][98126], advisory [INTEL-SA-00615].
2294
2295[98608]: https://github.com/rust-lang/rust/issues/98608
2296[98890]: https://github.com/rust-lang/rust/issues/98890
2297[98950]: https://github.com/rust-lang/rust/pull/98950
2298[98126]: https://github.com/rust-lang/rust/pull/98126
2299[INTEL-SA-00615]: https://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-00615.html
2300
2301Version 1.62.0 (2022-06-30)
2302==========================
2303
2304Language
2305--------
2306
2307- [Stabilize `#[derive(Default)]` on enums with a `#[default]` variant][94457]
2308- [Teach flow sensitive checks that visibly uninhabited call expressions never return][93313]
2309- [Fix constants not getting dropped if part of a diverging expression][94775]
2310- [Support unit struct/enum variant in destructuring assignment][95380]
2311- [Remove mutable_borrow_reservation_conflict lint and allow the code pattern][96268]
2312- [`const` functions may now specify `extern "C"` or `extern "Rust"`][95346]
2313
2314Compiler
2315--------
2316
2317- [linker: Stop using whole-archive on dependencies of dylibs][96436]
2318- [Make `unaligned_references` lint deny-by-default][95372]
2319 This lint is also a future compatibility lint, and is expected to eventually
2320 become a hard error.
2321- [Only add codegen backend to dep info if -Zbinary-dep-depinfo is used][93969]
2322- [Reject `#[thread_local]` attribute on non-static items][95006]
2323- [Add tier 3 `aarch64-pc-windows-gnullvm` and `x86_64-pc-windows-gnullvm` targets\*][94872]
2324- [Implement a lint to warn about unused macro rules][96150]
2325- [Promote `x86_64-unknown-none` target to Tier 2\*][95705]
2326
2327\* Refer to Rust's [platform support page][platform-support-doc] for more
2328 information on Rust's tiered platform support.
2329
2330Libraries
2331---------
2332
2333- [Windows: Use a pipe relay for chaining pipes][95841]
2334- [Replace Linux Mutex and Condvar with futex based ones.][95035]
2335- [Replace RwLock by a futex based one on Linux][95801]
2336- [std: directly use pthread in UNIX parker implementation][96393]
2337
2338Stabilized APIs
2339---------------
2340
2341- [`bool::then_some`]
2342- [`f32::total_cmp`]
2343- [`f64::total_cmp`]
2344- [`Stdin::lines`]
2345- [`windows::CommandExt::raw_arg`]
2346- [`impl<T: Default> Default for AssertUnwindSafe<T>`]
2347- [`From<Rc<str>> for Rc<[u8]>`][rc-u8-from-str]
2348- [`From<Arc<str>> for Arc<[u8]>`][arc-u8-from-str]
2349- [`FusedIterator for EncodeWide`]
2350- [RDM intrinsics on aarch64][stdarch/1285]
2351
2352Clippy
2353------
2354
2355- [Create clippy lint against unexpectedly late drop for temporaries in match scrutinee expressions][94206]
2356
2357Cargo
2358-----
2359
2360- Added the `cargo add` command for adding dependencies to `Cargo.toml` from
2361 the command-line.
2362 [docs](https://doc.rust-lang.org/nightly/cargo/commands/cargo-add.html)
2363- Package ID specs now support `name@version` syntax in addition to the
2364 previous `name:version` to align with the behavior in `cargo add` and other
2365 tools. `cargo install` and `cargo yank` also now support this syntax so the
2366 version does not need to passed as a separate flag.
2367- The `git` and `registry` directories in Cargo's home directory (usually
2368 `~/.cargo`) are now marked as cache directories so that they are not
2369 included in backups or content indexing (on Windows).
2370- Added automatic `@` argfile support, which will use "response files" if the
2371 command-line to `rustc` exceeds the operating system's limit.
2372
2373Compatibility Notes
2374-------------------
2375
2376- `cargo test` now passes `--target` to `rustdoc` if the specified target is
2377 the same as the host target.
2378 [#10594](https://github.com/rust-lang/cargo/pull/10594)
2379- [rustdoc: doctests are now run on unexported `macro_rules!` macros, matching other private items][96630]
2380- [rustdoc: Remove .woff font files][96279]
2381- [Enforce Copy bounds for repeat elements while considering lifetimes][95819]
2382- [Windows: Fix potential unsoundness by aborting if `File` reads or writes cannot
2383 complete synchronously][95469].
2384
2385Internal Changes
2386----------------
2387
2388- [Unify ReentrantMutex implementations across all platforms][96042]
2389
2390These changes provide no direct user facing benefits, but represent significant
2391improvements to the internals and overall performance of rustc
2392and related tools.
2393
2394[93313]: https://github.com/rust-lang/rust/pull/93313/
2395[93969]: https://github.com/rust-lang/rust/pull/93969/
2396[94206]: https://github.com/rust-lang/rust/pull/94206/
2397[94457]: https://github.com/rust-lang/rust/pull/94457/
2398[94775]: https://github.com/rust-lang/rust/pull/94775/
2399[94872]: https://github.com/rust-lang/rust/pull/94872/
2400[95006]: https://github.com/rust-lang/rust/pull/95006/
2401[95035]: https://github.com/rust-lang/rust/pull/95035/
2402[95346]: https://github.com/rust-lang/rust/pull/95346/
2403[95372]: https://github.com/rust-lang/rust/pull/95372/
2404[95380]: https://github.com/rust-lang/rust/pull/95380/
2405[95431]: https://github.com/rust-lang/rust/pull/95431/
2406[95469]: https://github.com/rust-lang/rust/pull/95469/
2407[95705]: https://github.com/rust-lang/rust/pull/95705/
2408[95801]: https://github.com/rust-lang/rust/pull/95801/
2409[95819]: https://github.com/rust-lang/rust/pull/95819/
2410[95841]: https://github.com/rust-lang/rust/pull/95841/
2411[96042]: https://github.com/rust-lang/rust/pull/96042/
2412[96150]: https://github.com/rust-lang/rust/pull/96150/
2413[96268]: https://github.com/rust-lang/rust/pull/96268/
2414[96279]: https://github.com/rust-lang/rust/pull/96279/
2415[96393]: https://github.com/rust-lang/rust/pull/96393/
2416[96436]: https://github.com/rust-lang/rust/pull/96436/
2417[96557]: https://github.com/rust-lang/rust/pull/96557/
2418[96630]: https://github.com/rust-lang/rust/pull/96630/
2419
2420[`bool::then_some`]: https://doc.rust-lang.org/stable/std/primitive.bool.html#method.then_some
2421[`f32::total_cmp`]: https://doc.rust-lang.org/stable/std/primitive.f32.html#method.total_cmp
2422[`f64::total_cmp`]: https://doc.rust-lang.org/stable/std/primitive.f64.html#method.total_cmp
2423[`Stdin::lines`]: https://doc.rust-lang.org/stable/std/io/struct.Stdin.html#method.lines
2424[`impl<T: Default> Default for AssertUnwindSafe<T>`]: https://doc.rust-lang.org/stable/std/panic/struct.AssertUnwindSafe.html#impl-Default
2425[rc-u8-from-str]: https://doc.rust-lang.org/stable/std/rc/struct.Rc.html#impl-From%3CRc%3Cstr%3E%3E
2426[arc-u8-from-str]: https://doc.rust-lang.org/stable/std/sync/struct.Arc.html#impl-From%3CArc%3Cstr%3E%3E
2427[stdarch/1285]: https://github.com/rust-lang/stdarch/pull/1285
2428[`windows::CommandExt::raw_arg`]: https://doc.rust-lang.org/stable/std/os/windows/process/trait.CommandExt.html#tymethod.raw_arg
2429[`FusedIterator for EncodeWide`]: https://doc.rust-lang.org/stable/std/os/windows/ffi/struct.EncodeWide.html#impl-FusedIterator
2430
2431Version 1.61.0 (2022-05-19)
2432==========================
2433
2434Language
2435--------
2436
2437- [`const fn` signatures can now include generic trait bounds][93827]
2438- [`const fn` signatures can now use `impl Trait` in argument and return position][93827]
2439- [Function pointers can now be created, cast, and passed around in a `const fn`][93827]
2440- [Recursive calls can now set the value of a function's opaque `impl Trait` return type][94081]
2441
2442Compiler
2443--------
2444
2445- [Linking modifier syntax in `#[link]` attributes and on the command line, as well as the `whole-archive` modifier specifically, are now supported][93901]
2446- [The `char` type is now described as UTF-32 in debuginfo][89887]
2447- The [`#[target_feature]`][target_feature] attribute [can now be used with aarch64 features][90621]
2448- X86 [`#[target_feature = "adx"]` is now stable][93745]
2449
2450Libraries
2451---------
2452
2453- [`ManuallyDrop<T>` is now documented to have the same layout as `T`][88375]
2454- [`#[ignore = "…"]` messages are printed when running tests][92714]
2455- [Consistently show absent stdio handles on Windows as NULL handles][93263]
2456- [Make `std::io::stdio::lock()` return `'static` handles.][93965] Previously, the creation of locked handles to stdin/stdout/stderr would borrow the handles being locked, which prevented writing `let out = std::io::stdout().lock();` because `out` would outlive the return value of `stdout()`. Such code now works, eliminating a common pitfall that affected many Rust users.
2457- [`Vec::from_raw_parts` is now less restrictive about its inputs][95016]
2458- [`std::thread::available_parallelism` now takes cgroup quotas into account.][92697] Since `available_parallelism` is often used to create a thread pool for parallel computation, which may be CPU-bound for performance, `available_parallelism` will return a value consistent with the ability to use that many threads continuously, if possible. For instance, in a container with 8 virtual CPUs but quotas only allowing for 50% usage, `available_parallelism` will return 4.
2459
2460Stabilized APIs
2461---------------
2462
2463- [`Pin::static_mut`]
2464- [`Pin::static_ref`]
2465- [`Vec::retain_mut`]
2466- [`VecDeque::retain_mut`]
2467- [`Write` for `Cursor<[u8; N]>`][cursor-write-array]
2468- [`std::os::unix::net::SocketAddr::from_pathname`]
2469- [`std::process::ExitCode`] and [`std::process::Termination`]. The stabilization of these two APIs now makes it possible for programs to return errors from `main` with custom exit codes.
2470- [`std::thread::JoinHandle::is_finished`]
2471
2472These APIs are now usable in const contexts:
2473
2474- [`<*const T>::offset` and `<*mut T>::offset`][ptr-offset]
2475- [`<*const T>::wrapping_offset` and `<*mut T>::wrapping_offset`][ptr-wrapping_offset]
2476- [`<*const T>::add` and `<*mut T>::add`][ptr-add]
2477- [`<*const T>::sub` and `<*mut T>::sub`][ptr-sub]
2478- [`<*const T>::wrapping_add` and `<*mut T>::wrapping_add`][ptr-wrapping_add]
2479- [`<*const T>::wrapping_sub` and `<*mut T>::wrapping_sub`][ptr-wrapping_sub]
2480- [`<[T]>::as_mut_ptr`][slice-as_mut_ptr]
2481- [`<[T]>::as_ptr_range`][slice-as_ptr_range]
2482- [`<[T]>::as_mut_ptr_range`][slice-as_mut_ptr_range]
2483
2484Cargo
2485-----
2486
2487No feature changes, but see compatibility notes.
2488
2489Compatibility Notes
2490-------------------
2491
2492- Previously native static libraries were linked as `whole-archive` in some cases, but now rustc tries not to use `whole-archive` unless explicitly requested. This [change][93901] may result in linking errors in some cases. To fix such errors, native libraries linked from the command line, build scripts, or [`#[link]` attributes][link-attr] need to
2493 - (more common) either be reordered to respect dependencies between them (if `a` depends on `b` then `a` should go first and `b` second)
2494 - (less common) or be updated to use the [`+whole-archive`] modifier.
2495- [Catching a second unwind from FFI code while cleaning up from a Rust panic now causes the process to abort][92911]
2496- [Proc macros no longer see `ident` matchers wrapped in groups][92472]
2497- [The number of `#` in `r#` raw string literals is now required to be less than 256][95251]
2498- [When checking that a dyn type satisfies a trait bound, supertrait bounds are now enforced][92285]
2499- [`cargo vendor` now only accepts one value for each `--sync` flag][cargo/10448]
2500- [`cfg` predicates in `all()` and `any()` are always evaluated to detect errors, instead of short-circuiting.][94295] The compatibility considerations here arise in nightly-only code that used the short-circuiting behavior of `all` to write something like `cfg(all(feature = "nightly", syntax-requiring-nightly))`, which will now fail to compile. Instead, use either `cfg_attr(feature = "nightly", ...)` or nested uses of `cfg`.
2501- [bootstrap: static-libstdcpp is now enabled by default, and can now be disabled when llvm-tools is enabled][94832]
2502
2503Internal Changes
2504----------------
2505
2506These changes provide no direct user facing benefits, but represent significant
2507improvements to the internals and overall performance of rustc
2508and related tools.
2509
2510- [debuginfo: Refactor debuginfo generation for types][94261]
2511- [Remove the everybody loops pass][93913]
2512
2513[88375]: https://github.com/rust-lang/rust/pull/88375/
2514[89887]: https://github.com/rust-lang/rust/pull/89887/
2515[90621]: https://github.com/rust-lang/rust/pull/90621/
2516[92285]: https://github.com/rust-lang/rust/pull/92285/
2517[92472]: https://github.com/rust-lang/rust/pull/92472/
2518[92697]: https://github.com/rust-lang/rust/pull/92697/
2519[92714]: https://github.com/rust-lang/rust/pull/92714/
2520[92911]: https://github.com/rust-lang/rust/pull/92911/
2521[93263]: https://github.com/rust-lang/rust/pull/93263/
2522[93745]: https://github.com/rust-lang/rust/pull/93745/
2523[93827]: https://github.com/rust-lang/rust/pull/93827/
2524[93901]: https://github.com/rust-lang/rust/pull/93901/
2525[93913]: https://github.com/rust-lang/rust/pull/93913/
2526[93965]: https://github.com/rust-lang/rust/pull/93965/
2527[94081]: https://github.com/rust-lang/rust/pull/94081/
2528[94261]: https://github.com/rust-lang/rust/pull/94261/
2529[94295]: https://github.com/rust-lang/rust/pull/94295/
2530[94832]: https://github.com/rust-lang/rust/pull/94832/
2531[95016]: https://github.com/rust-lang/rust/pull/95016/
2532[95251]: https://github.com/rust-lang/rust/pull/95251/
2533[`+whole-archive`]: https://doc.rust-lang.org/stable/rustc/command-line-arguments.html#linking-modifiers-whole-archive
2534[`Pin::static_mut`]: https://doc.rust-lang.org/stable/std/pin/struct.Pin.html#method.static_mut
2535[`Pin::static_ref`]: https://doc.rust-lang.org/stable/std/pin/struct.Pin.html#method.static_ref
2536[`Vec::retain_mut`]: https://doc.rust-lang.org/stable/std/vec/struct.Vec.html#method.retain_mut
2537[`VecDeque::retain_mut`]: https://doc.rust-lang.org/stable/std/collections/struct.VecDeque.html#method.retain_mut
2538[`std::os::unix::net::SocketAddr::from_pathname`]: https://doc.rust-lang.org/stable/std/os/unix/net/struct.SocketAddr.html#method.from_pathname
2539[`std::process::ExitCode`]: https://doc.rust-lang.org/stable/std/process/struct.ExitCode.html
2540[`std::process::Termination`]: https://doc.rust-lang.org/stable/std/process/trait.Termination.html
2541[`std::thread::JoinHandle::is_finished`]: https://doc.rust-lang.org/stable/std/thread/struct.JoinHandle.html#method.is_finished
2542[cargo/10448]: https://github.com/rust-lang/cargo/pull/10448/
2543[cursor-write-array]: https://doc.rust-lang.org/stable/std/io/struct.Cursor.html#impl-Write-4
2544[link-attr]: https://doc.rust-lang.org/stable/reference/items/external-blocks.html#the-link-attribute
2545[ptr-add]: https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.add
2546[ptr-offset]: https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.offset
2547[ptr-sub]: https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.sub
2548[ptr-wrapping_add]: https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.wrapping_add
2549[ptr-wrapping_offset]: https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.wrapping_offset
2550[ptr-wrapping_sub]: https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.wrapping_sub
2551[slice-as_mut_ptr]: https://doc.rust-lang.org/stable/std/primitive.slice.html#method.as_mut_ptr
2552[slice-as_mut_ptr_range]: https://doc.rust-lang.org/stable/std/primitive.slice.html#method.as_mut_ptr_range
2553[slice-as_ptr_range]: https://doc.rust-lang.org/stable/std/primitive.slice.html#method.as_ptr_range
2554[target_feature]: https://doc.rust-lang.org/reference/attributes/codegen.html#the-target_feature-attribute
2555
2556
2557Version 1.60.0 (2022-04-07)
2558==========================
2559
2560Language
2561--------
2562- [Stabilize `#[cfg(panic = "...")]` for either `"unwind"` or `"abort"`.][93658]
2563- [Stabilize `#[cfg(target_has_atomic = "...")]` for each integer size and `"ptr"`.][93824]
2564
2565Compiler
2566--------
2567- [Enable combining `+crt-static` and `relocation-model=pic` on `x86_64-unknown-linux-gnu`][86374]
2568- [Fixes wrong `unreachable_pub` lints on nested and glob public reexport][87487]
2569- [Stabilize `-Z instrument-coverage` as `-C instrument-coverage`][90132]
2570- [Stabilize `-Z print-link-args` as `--print link-args`][91606]
2571- [Add new Tier 3 target `mips64-openwrt-linux-musl`\*][92300]
2572- [Add new Tier 3 target `armv7-unknown-linux-uclibceabi` (softfloat)\*][92383]
2573- [Fix invalid removal of newlines from doc comments][92357]
2574- [Add kernel target for RustyHermit][92670]
2575- [Deny mixing bin crate type with lib crate types][92933]
2576- [Make rustc use `RUST_BACKTRACE=full` by default][93566]
2577- [Upgrade to LLVM 14][93577]
2578
2579\* Refer to Rust's [platform support page][platform-support-doc] for more
2580 information on Rust's tiered platform support.
2581
2582Libraries
2583---------
2584- [Guarantee call order for `sort_by_cached_key`][89621]
2585- [Improve `Duration::try_from_secs_f32`/`f64` accuracy by directly processing exponent and mantissa][90247]
2586- [Make `Instant::{duration_since, elapsed, sub}` saturating][89926]
2587- [Remove non-monotonic clocks workarounds in `Instant::now`][89926]
2588- [Make `BuildHasherDefault`, `iter::Empty` and `future::Pending` covariant][92630]
2589
2590Stabilized APIs
2591---------------
2592- [`Arc::new_cyclic`][arc_new_cyclic]
2593- [`Rc::new_cyclic`][rc_new_cyclic]
2594- [`slice::EscapeAscii`][slice_escape_ascii]
2595- [`<[u8]>::escape_ascii`][slice_u8_escape_ascii]
2596- [`u8::escape_ascii`][u8_escape_ascii]
2597- [`Vec::spare_capacity_mut`][vec_spare_capacity_mut]
2598- [`MaybeUninit::assume_init_drop`][assume_init_drop]
2599- [`MaybeUninit::assume_init_read`][assume_init_read]
2600- [`i8::abs_diff`][i8_abs_diff]
2601- [`i16::abs_diff`][i16_abs_diff]
2602- [`i32::abs_diff`][i32_abs_diff]
2603- [`i64::abs_diff`][i64_abs_diff]
2604- [`i128::abs_diff`][i128_abs_diff]
2605- [`isize::abs_diff`][isize_abs_diff]
2606- [`u8::abs_diff`][u8_abs_diff]
2607- [`u16::abs_diff`][u16_abs_diff]
2608- [`u32::abs_diff`][u32_abs_diff]
2609- [`u64::abs_diff`][u64_abs_diff]
2610- [`u128::abs_diff`][u128_abs_diff]
2611- [`usize::abs_diff`][usize_abs_diff]
2612- [`Display for io::ErrorKind`][display_error_kind]
2613- [`From<u8> for ExitCode`][from_u8_exit_code]
2614- [`Not for !` (the "never" type)][not_never]
2615- [_Op_`Assign<$t> for Wrapping<$t>`][wrapping_assign_ops]
2616- [`arch::is_aarch64_feature_detected!`][is_aarch64_feature_detected]
2617
2618Cargo
2619-----
2620- [Port cargo from `toml-rs` to `toml_edit`][cargo/10086]
2621- [Stabilize `-Ztimings` as `--timings`][cargo/10245]
2622- [Stabilize namespaced and weak dependency features.][cargo/10269]
2623- [Accept more `cargo:rustc-link-arg-*` types from build script output.][cargo/10274]
2624- [cargo-new should not add ignore rule on Cargo.lock inside subdirs][cargo/10379]
2625
2626Misc
2627----
2628- [Ship docs on Tier 2 platforms by reusing the closest Tier 1 platform docs][92800]
2629- [Drop rustc-docs from complete profile][93742]
2630- [bootstrap: tidy up flag handling for llvm build][93918]
2631
2632Compatibility Notes
2633-------------------
2634- [Remove compiler-rt linking hack on Android][83822]
2635- [Mitigations for platforms with non-monotonic clocks have been removed from
2636 `Instant::now`][89926]. On platforms that don't provide monotonic clocks, an
2637 instant is not guaranteed to be greater than an earlier instant anymore.
2638- [`Instant::{duration_since, elapsed, sub}` do not panic anymore on underflow,
2639 saturating to `0` instead][89926]. In the real world the panic happened mostly
2640 on platforms with buggy monotonic clock implementations rather than catching
2641 programming errors like reversing the start and end times. Such programming
2642 errors will now results in `0` rather than a panic.
2643- In a future release we're planning to increase the baseline requirements for
2644 the Linux kernel to version 3.2, and for glibc to version 2.17. We'd love
2645 your feedback in [PR #95026][95026].
2646
2647Internal Changes
2648----------------
2649
2650These changes provide no direct user facing benefits, but represent significant
2651improvements to the internals and overall performance of rustc
2652and related tools.
2653
2654- [Switch all libraries to the 2021 edition][92068]
2655
2656[83822]: https://github.com/rust-lang/rust/pull/83822
2657[86374]: https://github.com/rust-lang/rust/pull/86374
2658[87487]: https://github.com/rust-lang/rust/pull/87487
2659[89621]: https://github.com/rust-lang/rust/pull/89621
2660[89926]: https://github.com/rust-lang/rust/pull/89926
2661[90132]: https://github.com/rust-lang/rust/pull/90132
2662[90247]: https://github.com/rust-lang/rust/pull/90247
2663[91606]: https://github.com/rust-lang/rust/pull/91606
2664[92068]: https://github.com/rust-lang/rust/pull/92068
2665[92300]: https://github.com/rust-lang/rust/pull/92300
2666[92357]: https://github.com/rust-lang/rust/pull/92357
2667[92383]: https://github.com/rust-lang/rust/pull/92383
2668[92630]: https://github.com/rust-lang/rust/pull/92630
2669[92670]: https://github.com/rust-lang/rust/pull/92670
2670[92800]: https://github.com/rust-lang/rust/pull/92800
2671[92933]: https://github.com/rust-lang/rust/pull/92933
2672[93566]: https://github.com/rust-lang/rust/pull/93566
2673[93577]: https://github.com/rust-lang/rust/pull/93577
2674[93658]: https://github.com/rust-lang/rust/pull/93658
2675[93742]: https://github.com/rust-lang/rust/pull/93742
2676[93824]: https://github.com/rust-lang/rust/pull/93824
2677[93918]: https://github.com/rust-lang/rust/pull/93918
2678[95026]: https://github.com/rust-lang/rust/pull/95026
2679
2680[cargo/10086]: https://github.com/rust-lang/cargo/pull/10086
2681[cargo/10245]: https://github.com/rust-lang/cargo/pull/10245
2682[cargo/10269]: https://github.com/rust-lang/cargo/pull/10269
2683[cargo/10274]: https://github.com/rust-lang/cargo/pull/10274
2684[cargo/10379]: https://github.com/rust-lang/cargo/pull/10379
2685
2686[arc_new_cyclic]: https://doc.rust-lang.org/stable/std/sync/struct.Arc.html#method.new_cyclic
2687[rc_new_cyclic]: https://doc.rust-lang.org/stable/std/rc/struct.Rc.html#method.new_cyclic
2688[slice_escape_ascii]: https://doc.rust-lang.org/stable/std/slice/struct.EscapeAscii.html
2689[slice_u8_escape_ascii]: https://doc.rust-lang.org/stable/std/primitive.slice.html#method.escape_ascii
2690[u8_escape_ascii]: https://doc.rust-lang.org/stable/std/primitive.u8.html#method.escape_ascii
2691[vec_spare_capacity_mut]: https://doc.rust-lang.org/stable/std/vec/struct.Vec.html#method.spare_capacity_mut
2692[assume_init_drop]: https://doc.rust-lang.org/stable/std/mem/union.MaybeUninit.html#method.assume_init_drop
2693[assume_init_read]: https://doc.rust-lang.org/stable/std/mem/union.MaybeUninit.html#method.assume_init_read
2694[i8_abs_diff]: https://doc.rust-lang.org/stable/std/primitive.i8.html#method.abs_diff
2695[i16_abs_diff]: https://doc.rust-lang.org/stable/std/primitive.i16.html#method.abs_diff
2696[i32_abs_diff]: https://doc.rust-lang.org/stable/std/primitive.i32.html#method.abs_diff
2697[i64_abs_diff]: https://doc.rust-lang.org/stable/std/primitive.i64.html#method.abs_diff
2698[i128_abs_diff]: https://doc.rust-lang.org/stable/std/primitive.i128.html#method.abs_diff
2699[isize_abs_diff]: https://doc.rust-lang.org/stable/std/primitive.isize.html#method.abs_diff
2700[u8_abs_diff]: https://doc.rust-lang.org/stable/std/primitive.u8.html#method.abs_diff
2701[u16_abs_diff]: https://doc.rust-lang.org/stable/std/primitive.u16.html#method.abs_diff
2702[u32_abs_diff]: https://doc.rust-lang.org/stable/std/primitive.u32.html#method.abs_diff
2703[u64_abs_diff]: https://doc.rust-lang.org/stable/std/primitive.u64.html#method.abs_diff
2704[u128_abs_diff]: https://doc.rust-lang.org/stable/std/primitive.u128.html#method.abs_diff
2705[usize_abs_diff]: https://doc.rust-lang.org/stable/std/primitive.usize.html#method.abs_diff
2706[display_error_kind]: https://doc.rust-lang.org/stable/std/io/enum.ErrorKind.html#impl-Display
2707[from_u8_exit_code]: https://doc.rust-lang.org/stable/std/process/struct.ExitCode.html#impl-From%3Cu8%3E
2708[not_never]: https://doc.rust-lang.org/stable/std/primitive.never.html#impl-Not
2709[wrapping_assign_ops]: https://doc.rust-lang.org/stable/std/num/struct.Wrapping.html#trait-implementations
2710[is_aarch64_feature_detected]: https://doc.rust-lang.org/stable/std/arch/macro.is_aarch64_feature_detected.html
2711
2712Version 1.59.0 (2022-02-24)
2713==========================
2714
2715Language
2716--------
2717
2718- [Stabilize default arguments for const parameters and remove the ordering restriction for type and const parameters][90207]
2719- [Stabilize destructuring assignment][90521]
2720- [Relax private in public lint on generic bounds and where clauses of trait impls][90586]
2721- [Stabilize asm! and global_asm! for x86, x86_64, ARM, Aarch64, and RISC-V][91728]
2722
2723Compiler
2724--------
2725
2726- [Stabilize new symbol mangling format, leaving it opt-in (-Csymbol-mangling-version=v0)][90128]
2727- [Emit LLVM optimization remarks when enabled with `-Cremark`][90833]
2728- [Fix sparc64 ABI for aggregates with floating point members][91003]
2729- [Warn when a `#[test]`-like built-in attribute macro is present multiple times.][91172]
2730- [Add support for riscv64gc-unknown-freebsd][91284]
2731- [Stabilize `-Z emit-future-incompat` as `--json future-incompat`][91535]
2732- [Soft disable incremental compilation][94124]
2733
2734This release disables incremental compilation, unless the user has explicitly
2735opted in via the newly added RUSTC_FORCE_INCREMENTAL=1 environment variable.
2736This is due to a known and relatively frequently occurring bug in incremental
2737compilation, which causes builds to issue internal compiler errors. This
2738particular bug is already fixed on nightly, but that fix has not yet rolled out
2739to stable and is deemed too risky for a direct stable backport.
2740
2741As always, we encourage users to test with nightly and report bugs so that we
2742can track failures and fix issues earlier.
2743
2744See [94124] for more details.
2745
2746[94124]: https://github.com/rust-lang/rust/issues/94124
2747
2748Libraries
2749---------
2750
2751- [Remove unnecessary bounds for some Hash{Map,Set} methods][91593]
2752
2753Stabilized APIs
2754---------------
2755
2756- [`std::thread::available_parallelism`][available_parallelism]
2757- [`Result::copied`][result-copied]
2758- [`Result::cloned`][result-cloned]
2759- [`arch::asm!`][asm]
2760- [`arch::global_asm!`][global_asm]
2761- [`ops::ControlFlow::is_break`][is_break]
2762- [`ops::ControlFlow::is_continue`][is_continue]
2763- [`TryFrom<char> for u8`][try_from_char_u8]
2764- [`char::TryFromCharError`][try_from_char_err]
2765 implementing `Clone`, `Debug`, `Display`, `PartialEq`, `Copy`, `Eq`, `Error`
2766- [`iter::zip`][zip]
2767- [`NonZeroU8::is_power_of_two`][is_power_of_two8]
2768- [`NonZeroU16::is_power_of_two`][is_power_of_two16]
2769- [`NonZeroU32::is_power_of_two`][is_power_of_two32]
2770- [`NonZeroU64::is_power_of_two`][is_power_of_two64]
2771- [`NonZeroU128::is_power_of_two`][is_power_of_two128]
2772- [`NonZeroUsize::is_power_of_two`][is_power_of_two_usize]
2773- [`DoubleEndedIterator for ToLowercase`][lowercase]
2774- [`DoubleEndedIterator for ToUppercase`][uppercase]
2775- [`TryFrom<&mut [T]> for [T; N]`][tryfrom_ref_arr]
2776- [`UnwindSafe for Once`][unwindsafe_once]
2777- [`RefUnwindSafe for Once`][refunwindsafe_once]
2778- [armv8 neon intrinsics for aarch64][stdarch/1266]
2779
2780Const-stable:
2781
2782- [`mem::MaybeUninit::as_ptr`][muninit_ptr]
2783- [`mem::MaybeUninit::assume_init`][muninit_init]
2784- [`mem::MaybeUninit::assume_init_ref`][muninit_init_ref]
2785- [`ffi::CStr::from_bytes_with_nul_unchecked`][cstr_from_bytes]
2786
2787Cargo
2788-----
2789
2790- [Stabilize the `strip` profile option][cargo/10088]
2791- [Stabilize future-incompat-report][cargo/10165]
2792- [Support abbreviating `--release` as `-r`][cargo/10133]
2793- [Support `term.quiet` configuration][cargo/10152]
2794- [Remove `--host` from cargo {publish,search,login}][cargo/10145]
2795
2796Compatibility Notes
2797-------------------
2798
2799- [Refactor weak symbols in std::sys::unix][90846]
2800 This may add new, versioned, symbols when building with a newer glibc, as the
2801 standard library uses weak linkage rather than dynamically attempting to load
2802 certain symbols at runtime.
2803- [Deprecate crate_type and crate_name nested inside `#![cfg_attr]`][83744]
2804 This adds a future compatibility lint to supporting the use of cfg_attr
2805 wrapping either crate_type or crate_name specification within Rust files;
2806 it is recommended that users migrate to setting the equivalent command line
2807 flags.
2808- [Remove effect of `#[no_link]` attribute on name resolution][92034]
2809 This may expose new names, leading to conflicts with preexisting names in a
2810 given namespace and a compilation failure.
2811- [Cargo will document libraries before binaries.][cargo/10172]
2812- [Respect doc=false in dependencies, not just the root crate][cargo/10201]
2813- [Weaken guarantee around advancing underlying iterators in zip][83791]
2814- [Make split_inclusive() on an empty slice yield an empty output][89825]
2815- [Update std::env::temp_dir to use GetTempPath2 on Windows when available.][89999]
2816- [unreachable! was updated to match other formatting macro behavior on Rust 2021][92137]
2817
2818Internal Changes
2819----------------
2820
2821These changes provide no direct user facing benefits, but represent significant
2822improvements to the internals and overall performance of rustc
2823and related tools.
2824
2825- [Fix many cases of normalization-related ICEs][91255]
2826- [Replace dominators algorithm with simple Lengauer-Tarjan][85013]
2827- [Store liveness in interval sets for region inference][90637]
2828
2829- [Remove `in_band_lifetimes` from the compiler and standard library, in preparation for removing this
2830 unstable feature.][91867]
2831
2832[91867]: https://github.com/rust-lang/rust/issues/91867
2833[83744]: https://github.com/rust-lang/rust/pull/83744/
2834[83791]: https://github.com/rust-lang/rust/pull/83791/
2835[85013]: https://github.com/rust-lang/rust/pull/85013/
2836[89825]: https://github.com/rust-lang/rust/pull/89825/
2837[89999]: https://github.com/rust-lang/rust/pull/89999/
2838[90128]: https://github.com/rust-lang/rust/pull/90128/
2839[90207]: https://github.com/rust-lang/rust/pull/90207/
2840[90521]: https://github.com/rust-lang/rust/pull/90521/
2841[90586]: https://github.com/rust-lang/rust/pull/90586/
2842[90637]: https://github.com/rust-lang/rust/pull/90637/
2843[90833]: https://github.com/rust-lang/rust/pull/90833/
2844[90846]: https://github.com/rust-lang/rust/pull/90846/
2845[91003]: https://github.com/rust-lang/rust/pull/91003/
2846[91172]: https://github.com/rust-lang/rust/pull/91172/
2847[91255]: https://github.com/rust-lang/rust/pull/91255/
2848[91284]: https://github.com/rust-lang/rust/pull/91284/
2849[91535]: https://github.com/rust-lang/rust/pull/91535/
2850[91593]: https://github.com/rust-lang/rust/pull/91593/
2851[91728]: https://github.com/rust-lang/rust/pull/91728/
2852[91878]: https://github.com/rust-lang/rust/pull/91878/
2853[91896]: https://github.com/rust-lang/rust/pull/91896/
2854[91926]: https://github.com/rust-lang/rust/pull/91926/
2855[91984]: https://github.com/rust-lang/rust/pull/91984/
2856[92020]: https://github.com/rust-lang/rust/pull/92020/
2857[92034]: https://github.com/rust-lang/rust/pull/92034/
2858[92137]: https://github.com/rust-lang/rust/pull/92137/
2859[92483]: https://github.com/rust-lang/rust/pull/92483/
2860[cargo/10088]: https://github.com/rust-lang/cargo/pull/10088/
2861[cargo/10133]: https://github.com/rust-lang/cargo/pull/10133/
2862[cargo/10145]: https://github.com/rust-lang/cargo/pull/10145/
2863[cargo/10152]: https://github.com/rust-lang/cargo/pull/10152/
2864[cargo/10165]: https://github.com/rust-lang/cargo/pull/10165/
2865[cargo/10172]: https://github.com/rust-lang/cargo/pull/10172/
2866[cargo/10201]: https://github.com/rust-lang/cargo/pull/10201/
2867[cargo/10269]: https://github.com/rust-lang/cargo/pull/10269/
2868
2869[cstr_from_bytes]: https://doc.rust-lang.org/stable/std/ffi/struct.CStr.html#method.from_bytes_with_nul_unchecked
2870[muninit_ptr]: https://doc.rust-lang.org/stable/std/mem/union.MaybeUninit.html#method.as_ptr
2871[muninit_init]: https://doc.rust-lang.org/stable/std/mem/union.MaybeUninit.html#method.assume_init
2872[muninit_init_ref]: https://doc.rust-lang.org/stable/std/mem/union.MaybeUninit.html#method.assume_init_ref
2873[unwindsafe_once]: https://doc.rust-lang.org/stable/std/sync/struct.Once.html#impl-UnwindSafe
2874[refunwindsafe_once]: https://doc.rust-lang.org/stable/std/sync/struct.Once.html#impl-RefUnwindSafe
2875[tryfrom_ref_arr]: https://doc.rust-lang.org/stable/std/convert/trait.TryFrom.html#impl-TryFrom%3C%26%27_%20mut%20%5BT%5D%3E
2876[lowercase]: https://doc.rust-lang.org/stable/std/char/struct.ToLowercase.html#impl-DoubleEndedIterator
2877[uppercase]: https://doc.rust-lang.org/stable/std/char/struct.ToUppercase.html#impl-DoubleEndedIterator
2878[try_from_char_err]: https://doc.rust-lang.org/stable/std/char/struct.TryFromCharError.html
2879[available_parallelism]: https://doc.rust-lang.org/stable/std/thread/fn.available_parallelism.html
2880[result-copied]: https://doc.rust-lang.org/stable/std/result/enum.Result.html#method.copied
2881[result-cloned]: https://doc.rust-lang.org/stable/std/result/enum.Result.html#method.cloned
2882[asm]: https://doc.rust-lang.org/stable/core/arch/macro.asm.html
2883[global_asm]: https://doc.rust-lang.org/stable/core/arch/macro.global_asm.html
2884[is_break]: https://doc.rust-lang.org/stable/std/ops/enum.ControlFlow.html#method.is_break
2885[is_continue]: https://doc.rust-lang.org/stable/std/ops/enum.ControlFlow.html#method.is_continue
2886[try_from_char_u8]: https://doc.rust-lang.org/stable/std/primitive.char.html#impl-TryFrom%3Cchar%3E
2887[zip]: https://doc.rust-lang.org/stable/std/iter/fn.zip.html
2888[is_power_of_two8]: https://doc.rust-lang.org/stable/core/num/struct.NonZeroU8.html#method.is_power_of_two
2889[is_power_of_two16]: https://doc.rust-lang.org/stable/core/num/struct.NonZeroU16.html#method.is_power_of_two
2890[is_power_of_two32]: https://doc.rust-lang.org/stable/core/num/struct.NonZeroU32.html#method.is_power_of_two
2891[is_power_of_two64]: https://doc.rust-lang.org/stable/core/num/struct.NonZeroU64.html#method.is_power_of_two
2892[is_power_of_two128]: https://doc.rust-lang.org/stable/core/num/struct.NonZeroU128.html#method.is_power_of_two
2893[is_power_of_two_usize]: https://doc.rust-lang.org/stable/core/num/struct.NonZeroUsize.html#method.is_power_of_two
2894[stdarch/1266]: https://github.com/rust-lang/stdarch/pull/1266
2895
2896Version 1.58.1 (2022-01-20)
2897===========================
2898
2899* Fix race condition in `std::fs::remove_dir_all` ([CVE-2022-21658])
2900* [Handle captured arguments in the `useless_format` Clippy lint][clippy/8295]
2901* [Move `non_send_fields_in_send_ty` Clippy lint to nursery][clippy/8075]
2902* [Fix wrong error message displayed when some imports are missing][91254]
2903* [Fix rustfmt not formatting generated files from stdin][92912]
2904
2905[CVE-2022-21658]: https://www.cve.org/CVERecord?id=CVE-2022-21658
2906[91254]: https://github.com/rust-lang/rust/pull/91254
2907[92912]: https://github.com/rust-lang/rust/pull/92912
2908[clippy/8075]: https://github.com/rust-lang/rust-clippy/pull/8075
2909[clippy/8295]: https://github.com/rust-lang/rust-clippy/pull/8295
2910
2911Version 1.58.0 (2022-01-13)
2912==========================
2913
2914Language
2915--------
2916
2917- [Format strings can now capture arguments simply by writing `{ident}` in the string.][90473] This works in all macros accepting format strings. Support for this in `panic!` (`panic!("{ident}")`) requires the 2021 edition; panic invocations in previous editions that appear to be trying to use this will result in a warning lint about not having the intended effect.
2918- [`*const T` pointers can now be dereferenced in const contexts.][89551]
2919- [The rules for when a generic struct implements `Unsize` have been relaxed.][90417]
2920
2921Compiler
2922--------
2923
2924- [Add LLVM CFI support to the Rust compiler][89652]
2925- [Stabilize -Z strip as -C strip][90058]. Note that while release builds already don't add debug symbols for the code you compile, the compiled standard library that ships with Rust includes debug symbols, so you may want to use the `strip` option to remove these symbols to produce smaller release binaries. Note that this release only includes support in rustc, not directly in cargo.
2926- [Add support for LLVM coverage mapping format versions 5 and 6][91207]
2927- [Emit LLVM optimization remarks when enabled with `-Cremark`][90833]
2928- [Update the minimum external LLVM to 12][90175]
2929- [Add `x86_64-unknown-none` at Tier 3*][89062]
2930- [Build musl dist artifacts with debuginfo enabled][90733]. When building release binaries using musl, you may want to use the newly stabilized strip option to remove these debug symbols, reducing the size of your binaries.
2931- [Don't abort compilation after giving a lint error][87337]
2932- [Error messages point at the source of trait bound obligations in more places][89580]
2933
2934\* Refer to Rust's [platform support page][platform-support-doc] for more
2935 information on Rust's tiered platform support.
2936
2937Libraries
2938---------
2939
2940- [All remaining functions in the standard library have `#[must_use]` annotations where appropriate][89692], producing a warning when ignoring their return value. This helps catch mistakes such as expecting a function to mutate a value in place rather than return a new value.
2941- [Paths are automatically canonicalized on Windows for operations that support it][89174]
2942- [Re-enable debug checks for `copy` and `copy_nonoverlapping`][90041]
2943- [Implement `RefUnwindSafe` for `Rc<T>`][87467]
2944- [Make RSplit<T, P>: Clone not require T: Clone][90117]
2945- [Implement `Termination` for `Result<Infallible, E>`][88601]. This allows writing `fn main() -> Result<Infallible, ErrorType>`, for a program whose successful exits never involve returning from `main` (for instance, a program that calls `exit`, or that uses `exec` to run another program).
2946
2947Stabilized APIs
2948---------------
2949
2950- [`Metadata::is_symlink`]
2951- [`Path::is_symlink`]
2952- [`{integer}::saturating_div`]
2953- [`Option::unwrap_unchecked`]
2954- [`Result::unwrap_unchecked`]
2955- [`Result::unwrap_err_unchecked`]
2956- [`File::options`]
2957
2958These APIs are now usable in const contexts:
2959
2960- [`Duration::new`]
2961- [`Duration::checked_add`]
2962- [`Duration::saturating_add`]
2963- [`Duration::checked_sub`]
2964- [`Duration::saturating_sub`]
2965- [`Duration::checked_mul`]
2966- [`Duration::saturating_mul`]
2967- [`Duration::checked_div`]
2968
2969Cargo
2970-----
2971
2972- [Add --message-format for install command][cargo/10107]
2973- [Warn when alias shadows external subcommand][cargo/10082]
2974
2975Rustdoc
2976-------
2977
2978- [Show all Deref implementations recursively in rustdoc][90183]
2979- [Use computed visibility in rustdoc][88447]
2980
2981Compatibility Notes
2982-------------------
2983
2984- [Try all stable method candidates first before trying unstable ones][90329]. This change ensures that adding new nightly-only methods to the Rust standard library will not break code invoking methods of the same name from traits outside the standard library.
2985- Windows: [`std::process::Command` will no longer search the current directory for executables.][87704]
2986- [All proc-macro backward-compatibility lints are now deny-by-default.][88041]
2987- [proc_macro: Append .0 to unsuffixed float if it would otherwise become int token][90297]
2988- [Refactor weak symbols in std::sys::unix][90846]. This optimizes accesses to glibc functions, by avoiding the use of dlopen. This does not increase the [minimum expected version of glibc](https://doc.rust-lang.org/nightly/rustc/platform-support.html). However, software distributions that use symbol versions to detect library dependencies, and which take weak symbols into account in that analysis, may detect rust binaries as requiring newer versions of glibc.
2989- [rustdoc now rejects some unexpected semicolons in doctests][91026]
2990
2991Internal Changes
2992----------------
2993
2994These changes provide no direct user facing benefits, but represent significant
2995improvements to the internals and overall performance of rustc
2996and related tools.
2997
2998- [Implement coherence checks for negative trait impls][90104]
2999- [Add rustc lint, warning when iterating over hashmaps][89558]
3000- [Optimize live point computation][90491]
3001- [Enable verification for 1/32nd of queries loaded from disk][90361]
3002- [Implement version of normalize_erasing_regions that allows for normalization failure][91255]
3003
3004[87337]: https://github.com/rust-lang/rust/pull/87337/
3005[87467]: https://github.com/rust-lang/rust/pull/87467/
3006[87704]: https://github.com/rust-lang/rust/pull/87704/
3007[88041]: https://github.com/rust-lang/rust/pull/88041/
3008[88447]: https://github.com/rust-lang/rust/pull/88447/
3009[88601]: https://github.com/rust-lang/rust/pull/88601/
3010[89062]: https://github.com/rust-lang/rust/pull/89062/
3011[89174]: https://github.com/rust-lang/rust/pull/89174/
3012[89551]: https://github.com/rust-lang/rust/pull/89551/
3013[89558]: https://github.com/rust-lang/rust/pull/89558/
3014[89580]: https://github.com/rust-lang/rust/pull/89580/
3015[89652]: https://github.com/rust-lang/rust/pull/89652/
3016[90041]: https://github.com/rust-lang/rust/pull/90041/
3017[90058]: https://github.com/rust-lang/rust/pull/90058/
3018[90104]: https://github.com/rust-lang/rust/pull/90104/
3019[90117]: https://github.com/rust-lang/rust/pull/90117/
3020[90175]: https://github.com/rust-lang/rust/pull/90175/
3021[90183]: https://github.com/rust-lang/rust/pull/90183/
3022[90297]: https://github.com/rust-lang/rust/pull/90297/
3023[90329]: https://github.com/rust-lang/rust/pull/90329/
3024[90361]: https://github.com/rust-lang/rust/pull/90361/
3025[90417]: https://github.com/rust-lang/rust/pull/90417/
3026[90473]: https://github.com/rust-lang/rust/pull/90473/
3027[90491]: https://github.com/rust-lang/rust/pull/90491/
3028[90733]: https://github.com/rust-lang/rust/pull/90733/
3029[90833]: https://github.com/rust-lang/rust/pull/90833/
3030[90846]: https://github.com/rust-lang/rust/pull/90846/
3031[91026]: https://github.com/rust-lang/rust/pull/91026/
3032[91207]: https://github.com/rust-lang/rust/pull/91207/
3033[91255]: https://github.com/rust-lang/rust/pull/91255/
3034[cargo/10082]: https://github.com/rust-lang/cargo/pull/10082/
3035[cargo/10107]: https://github.com/rust-lang/cargo/pull/10107/
3036[`Metadata::is_symlink`]: https://doc.rust-lang.org/stable/std/fs/struct.Metadata.html#method.is_symlink
3037[`Path::is_symlink`]: https://doc.rust-lang.org/stable/std/path/struct.Path.html#method.is_symlink
3038[`{integer}::saturating_div`]: https://doc.rust-lang.org/stable/std/primitive.i8.html#method.saturating_div
3039[`Option::unwrap_unchecked`]: https://doc.rust-lang.org/stable/std/option/enum.Option.html#method.unwrap_unchecked
3040[`Result::unwrap_unchecked`]: https://doc.rust-lang.org/stable/std/result/enum.Result.html#method.unwrap_unchecked
3041[`Result::unwrap_err_unchecked`]: https://doc.rust-lang.org/stable/std/result/enum.Result.html#method.unwrap_err_unchecked
3042[`File::options`]: https://doc.rust-lang.org/stable/std/fs/struct.File.html#method.options
3043[`Duration::new`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.new
3044
3045Version 1.57.0 (2021-12-02)
3046==========================
3047
3048Language
3049--------
3050
3051- [Macro attributes may follow `#[derive]` and will see the original (pre-`cfg`) input.][87220]
3052- [Accept curly-brace macros in expressions, like `m!{ .. }.method()` and `m!{ .. }?`.][88690]
3053- [Allow panicking in constant evaluation.][89508]
3054- [Ignore derived `Clone` and `Debug` implementations during dead code analysis.][85200]
3055
3056Compiler
3057--------
3058
3059- [Create more accurate debuginfo for vtables.][89597]
3060- [Add `armv6k-nintendo-3ds` at Tier 3\*.][88529]
3061- [Add `armv7-unknown-linux-uclibceabihf` at Tier 3\*.][88952]
3062- [Add `m68k-unknown-linux-gnu` at Tier 3\*.][88321]
3063- [Add SOLID targets at Tier 3\*:][86191] `aarch64-kmc-solid_asp3`, `armv7a-kmc-solid_asp3-eabi`, `armv7a-kmc-solid_asp3-eabihf`
3064
3065\* Refer to Rust's [platform support page][platform-support-doc] for more
3066 information on Rust's tiered platform support.
3067
3068Libraries
3069---------
3070
3071- [Avoid allocations and copying in `Vec::leak`][89337]
3072- [Add `#[repr(i8)]` to `Ordering`][89507]
3073- [Optimize `File::read_to_end` and `read_to_string`][89582]
3074- [Update to Unicode 14.0][89614]
3075- [Many more functions are marked `#[must_use]`][89692], producing a warning
3076 when ignoring their return value. This helps catch mistakes such as expecting
3077 a function to mutate a value in place rather than return a new value.
3078
3079Stabilised APIs
3080---------------
3081
3082- [`[T; N]::as_mut_slice`][`array::as_mut_slice`]
3083- [`[T; N]::as_slice`][`array::as_slice`]
3084- [`collections::TryReserveError`]
3085- [`HashMap::try_reserve`]
3086- [`HashSet::try_reserve`]
3087- [`String::try_reserve`]
3088- [`String::try_reserve_exact`]
3089- [`Vec::try_reserve`]
3090- [`Vec::try_reserve_exact`]
3091- [`VecDeque::try_reserve`]
3092- [`VecDeque::try_reserve_exact`]
3093- [`Iterator::map_while`]
3094- [`iter::MapWhile`]
3095- [`proc_macro::is_available`]
3096- [`Command::get_program`]
3097- [`Command::get_args`]
3098- [`Command::get_envs`]
3099- [`Command::get_current_dir`]
3100- [`CommandArgs`]
3101- [`CommandEnvs`]
3102
3103These APIs are now usable in const contexts:
3104
3105- [`hint::unreachable_unchecked`]
3106
3107Cargo
3108-----
3109
3110- [Stabilize custom profiles][cargo/9943]
3111
3112Compatibility notes
3113-------------------
3114
3115- [Ignore derived `Clone` and `Debug` implementations during dead code analysis.][85200]
3116 This will break some builds that set `#![deny(dead_code)]`.
3117
3118Internal changes
3119----------------
3120These changes provide no direct user facing benefits, but represent significant
3121improvements to the internals and overall performance of rustc
3122and related tools.
3123
3124- [Added an experimental backend for codegen with `libgccjit`.][87260]
3125
3126[85200]: https://github.com/rust-lang/rust/pull/85200/
3127[86191]: https://github.com/rust-lang/rust/pull/86191/
3128[87220]: https://github.com/rust-lang/rust/pull/87220/
3129[87260]: https://github.com/rust-lang/rust/pull/87260/
3130[88321]: https://github.com/rust-lang/rust/pull/88321/
3131[88529]: https://github.com/rust-lang/rust/pull/88529/
3132[88690]: https://github.com/rust-lang/rust/pull/88690/
3133[88952]: https://github.com/rust-lang/rust/pull/88952/
3134[89337]: https://github.com/rust-lang/rust/pull/89337/
3135[89507]: https://github.com/rust-lang/rust/pull/89507/
3136[89508]: https://github.com/rust-lang/rust/pull/89508/
3137[89582]: https://github.com/rust-lang/rust/pull/89582/
3138[89597]: https://github.com/rust-lang/rust/pull/89597/
3139[89614]: https://github.com/rust-lang/rust/pull/89614/
3140[89692]: https://github.com/rust-lang/rust/issues/89692/
3141[cargo/9943]: https://github.com/rust-lang/cargo/pull/9943/
3142[`array::as_mut_slice`]: https://doc.rust-lang.org/std/primitive.array.html#method.as_mut_slice
3143[`array::as_slice`]: https://doc.rust-lang.org/std/primitive.array.html#method.as_slice
3144[`collections::TryReserveError`]: https://doc.rust-lang.org/std/collections/struct.TryReserveError.html
3145[`HashMap::try_reserve`]: https://doc.rust-lang.org/std/collections/hash_map/struct.HashMap.html#method.try_reserve
3146[`HashSet::try_reserve`]: https://doc.rust-lang.org/std/collections/hash_set/struct.HashSet.html#method.try_reserve
3147[`String::try_reserve`]: https://doc.rust-lang.org/alloc/string/struct.String.html#method.try_reserve
3148[`String::try_reserve_exact`]: https://doc.rust-lang.org/alloc/string/struct.String.html#method.try_reserve_exact
3149[`Vec::try_reserve`]: https://doc.rust-lang.org/std/vec/struct.Vec.html#method.try_reserve
3150[`Vec::try_reserve_exact`]: https://doc.rust-lang.org/std/vec/struct.Vec.html#method.try_reserve_exact
3151[`VecDeque::try_reserve`]: https://doc.rust-lang.org/std/collections/struct.VecDeque.html#method.try_reserve
3152[`VecDeque::try_reserve_exact`]: https://doc.rust-lang.org/std/collections/struct.VecDeque.html#method.try_reserve_exact
3153[`Iterator::map_while`]: https://doc.rust-lang.org/std/iter/trait.Iterator.html#method.map_while
3154[`iter::MapWhile`]: https://doc.rust-lang.org/std/iter/struct.MapWhile.html
3155[`proc_macro::is_available`]: https://doc.rust-lang.org/proc_macro/fn.is_available.html
3156[`Command::get_program`]: https://doc.rust-lang.org/std/process/struct.Command.html#method.get_program
3157[`Command::get_args`]: https://doc.rust-lang.org/std/process/struct.Command.html#method.get_args
3158[`Command::get_envs`]: https://doc.rust-lang.org/std/process/struct.Command.html#method.get_envs
3159[`Command::get_current_dir`]: https://doc.rust-lang.org/std/process/struct.Command.html#method.get_current_dir
3160[`CommandArgs`]: https://doc.rust-lang.org/std/process/struct.CommandArgs.html
3161[`CommandEnvs`]: https://doc.rust-lang.org/std/process/struct.CommandEnvs.html
3162
3163Version 1.56.1 (2021-11-01)
3164===========================
3165
3166- New lints to detect the presence of bidirectional-override Unicode
3167 codepoints in the compiled source code ([CVE-2021-42574])
3168
3169[CVE-2021-42574]: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-42574
3170
3171Version 1.56.0 (2021-10-21)
3172========================
3173
3174Language
3175--------
3176
3177- [The 2021 Edition is now stable.][rust#88100]
3178 See [the edition guide][rust-2021-edition-guide] for more details.
3179- [The pattern in `binding @ pattern` can now also introduce new bindings.][rust#85305]
3180- [Union field access is permitted in `const fn`.][rust#85769]
3181
3182[rust-2021-edition-guide]: https://doc.rust-lang.org/nightly/edition-guide/rust-2021/index.html
3183
3184Compiler
3185--------
3186
3187- [Upgrade to LLVM 13.][rust#87570]
3188- [Support memory, address, and thread sanitizers on aarch64-unknown-freebsd.][rust#88023]
3189- [Allow specifying a deployment target version for all iOS targets][rust#87699]
3190- [Warnings can be forced on with `--force-warn`.][rust#87472]
3191 This feature is primarily intended for usage by `cargo fix`, rather than end users.
3192- [Promote `aarch64-apple-ios-sim` to Tier 2\*.][rust#87760]
3193- [Add `powerpc-unknown-freebsd` at Tier 3\*.][rust#87370]
3194- [Add `riscv32imc-esp-espidf` at Tier 3\*.][rust#87666]
3195
3196\* Refer to Rust's [platform support page][platform-support-doc] for more
3197information on Rust's tiered platform support.
3198
3199Libraries
3200---------
3201
3202- [Allow writing of incomplete UTF-8 sequences via stdout/stderr on Windows.][rust#83342]
3203 The Windows console still requires valid Unicode, but this change allows
3204 splitting a UTF-8 character across multiple write calls. This allows, for
3205 instance, programs that just read and write data buffers (e.g. copying a file
3206 to stdout) without regard for Unicode or character boundaries.
3207- [Prefer `AtomicU{64,128}` over Mutex for Instant backsliding protection.][rust#83093]
3208 For this use case, atomics scale much better under contention.
3209- [Implement `Extend<(A, B)>` for `(Extend<A>, Extend<B>)`][rust#85835]
3210- [impl Default, Copy, Clone for std::io::Sink and std::io::Empty][rust#86744]
3211- [`impl From<[(K, V); N]>` for all collections.][rust#84111]
3212- [Remove `P: Unpin` bound on impl Future for Pin.][rust#81363]
3213- [Treat invalid environment variable names as nonexistent.][rust#86183]
3214 Previously, the environment functions would panic if given a variable name
3215 with an internal null character or equal sign (`=`). Now, these functions will
3216 just treat such names as nonexistent variables, since the OS cannot represent
3217 the existence of a variable with such a name.
3218
3219Stabilised APIs
3220---------------
3221
3222- [`std::os::unix::fs::chroot`]
3223- [`UnsafeCell::raw_get`]
3224- [`BufWriter::into_parts`]
3225- [`core::panic::{UnwindSafe, RefUnwindSafe, AssertUnwindSafe}`]
3226 These APIs were previously stable in `std`, but are now also available in `core`.
3227- [`Vec::shrink_to`]
3228- [`String::shrink_to`]
3229- [`OsString::shrink_to`]
3230- [`PathBuf::shrink_to`]
3231- [`BinaryHeap::shrink_to`]
3232- [`VecDeque::shrink_to`]
3233- [`HashMap::shrink_to`]
3234- [`HashSet::shrink_to`]
3235
3236These APIs are now usable in const contexts:
3237
3238- [`std::mem::transmute`]
3239- [`[T]::first`][`slice::first`]
3240- [`[T]::split_first`][`slice::split_first`]
3241- [`[T]::last`][`slice::last`]
3242- [`[T]::split_last`][`slice::split_last`]
3243
3244Cargo
3245-----
3246
3247- [Cargo supports specifying a minimum supported Rust version in Cargo.toml.][`rust-version`]
3248 This has no effect at present on dependency version selection.
3249 We encourage crates to specify their minimum supported Rust version, and we encourage CI systems
3250 that support Rust code to include a crate's specified minimum version in the test matrix for that
3251 crate by default.
3252
3253Compatibility notes
3254-------------------
3255
3256- [Update to new argument parsing rules on Windows.][rust#87580]
3257 This adjusts Rust's standard library to match the behavior of the standard
3258 libraries for C/C++. The rules have changed slightly over time, and this PR
3259 brings us to the latest set of rules (changed in 2008).
3260- [Disallow the aapcs calling convention on aarch64][rust#88399]
3261 This was already not supported by LLVM; this change surfaces this lack of
3262 support with a better error message.
3263- [Make `SEMICOLON_IN_EXPRESSIONS_FROM_MACROS` warn by default][rust#87385]
3264- [Warn when an escaped newline skips multiple lines.][rust#87671]
3265- [Calls to `libc::getpid` / `std::process::id` from `Command::pre_exec`
3266 may return different values on glibc <= 2.24.][rust#81825]
3267 Rust now invokes the `clone3` system call directly, when available, to use new functionality
3268 available via that system call. Older versions of glibc cache the result of `getpid`, and only
3269 update that cache when calling glibc's clone/fork functions, so a direct system call bypasses
3270 that cache update. glibc 2.25 and newer no longer cache `getpid` for exactly this reason.
3271
3272Internal changes
3273----------------
3274These changes provide no direct user facing benefits, but represent significant
3275improvements to the internals and overall performance of rustc
3276and related tools.
3277
3278- [LLVM is compiled with PGO in published x86_64-unknown-linux-gnu artifacts.][rust#88069]
3279 This improves the performance of most Rust builds.
3280- [Unify representation of macros in internal data structures.][rust#88019]
3281 This change fixes a host of bugs with the handling of macros by the compiler,
3282 as well as rustdoc.
3283
3284[`std::os::unix::fs::chroot`]: https://doc.rust-lang.org/stable/std/os/unix/fs/fn.chroot.html
3285[`UnsafeCell::raw_get`]: https://doc.rust-lang.org/stable/std/cell/struct.UnsafeCell.html#method.raw_get
3286[`BufWriter::into_parts`]: https://doc.rust-lang.org/stable/std/io/struct.BufWriter.html#method.into_parts
3287[`core::panic::{UnwindSafe, RefUnwindSafe, AssertUnwindSafe}`]: https://github.com/rust-lang/rust/pull/84662
3288[`Vec::shrink_to`]: https://doc.rust-lang.org/stable/std/vec/struct.Vec.html#method.shrink_to
3289[`String::shrink_to`]: https://doc.rust-lang.org/stable/std/string/struct.String.html#method.shrink_to
3290[`OsString::shrink_to`]: https://doc.rust-lang.org/stable/std/ffi/struct.OsString.html#method.shrink_to
3291[`PathBuf::shrink_to`]: https://doc.rust-lang.org/stable/std/path/struct.PathBuf.html#method.shrink_to
3292[`BinaryHeap::shrink_to`]: https://doc.rust-lang.org/stable/std/collections/struct.BinaryHeap.html#method.shrink_to
3293[`VecDeque::shrink_to`]: https://doc.rust-lang.org/stable/std/collections/struct.VecDeque.html#method.shrink_to
3294[`HashMap::shrink_to`]: https://doc.rust-lang.org/stable/std/collections/hash_map/struct.HashMap.html#method.shrink_to
3295[`HashSet::shrink_to`]: https://doc.rust-lang.org/stable/std/collections/hash_set/struct.HashSet.html#method.shrink_to
3296[`std::mem::transmute`]: https://doc.rust-lang.org/stable/std/mem/fn.transmute.html
3297[`slice::first`]: https://doc.rust-lang.org/stable/std/primitive.slice.html#method.first
3298[`slice::split_first`]: https://doc.rust-lang.org/stable/std/primitive.slice.html#method.split_first
3299[`slice::last`]: https://doc.rust-lang.org/stable/std/primitive.slice.html#method.last
3300[`slice::split_last`]: https://doc.rust-lang.org/stable/std/primitive.slice.html#method.split_last
3301[`rust-version`]: https://doc.rust-lang.org/nightly/cargo/reference/manifest.html#the-rust-version-field
3302[rust#87671]: https://github.com/rust-lang/rust/pull/87671
3303[rust#86183]: https://github.com/rust-lang/rust/pull/86183
3304[rust#87385]: https://github.com/rust-lang/rust/pull/87385
3305[rust#88100]: https://github.com/rust-lang/rust/pull/88100
3306[rust#85305]: https://github.com/rust-lang/rust/pull/85305
3307[rust#88069]: https://github.com/rust-lang/rust/pull/88069
3308[rust#87472]: https://github.com/rust-lang/rust/pull/87472
3309[rust#87699]: https://github.com/rust-lang/rust/pull/87699
3310[rust#87570]: https://github.com/rust-lang/rust/pull/87570
3311[rust#88023]: https://github.com/rust-lang/rust/pull/88023
3312[rust#87760]: https://github.com/rust-lang/rust/pull/87760
3313[rust#87370]: https://github.com/rust-lang/rust/pull/87370
3314[rust#87580]: https://github.com/rust-lang/rust/pull/87580
3315[rust#83342]: https://github.com/rust-lang/rust/pull/83342
3316[rust#83093]: https://github.com/rust-lang/rust/pull/83093
3317[rust#85835]: https://github.com/rust-lang/rust/pull/85835
3318[rust#86744]: https://github.com/rust-lang/rust/pull/86744
3319[rust#81363]: https://github.com/rust-lang/rust/pull/81363
3320[rust#84111]: https://github.com/rust-lang/rust/pull/84111
3321[rust#85769]: https://github.com/rust-lang/rust/pull/85769#issuecomment-854363720
3322[rust#88399]: https://github.com/rust-lang/rust/pull/88399
3323[rust#81825]: https://github.com/rust-lang/rust/pull/81825#issuecomment-808406918
3324[rust#88019]: https://github.com/rust-lang/rust/pull/88019
3325[rust#87666]: https://github.com/rust-lang/rust/pull/87666
3326
3327Version 1.55.0 (2021-09-09)
3328============================
3329
3330Language
3331--------
3332- [You can now write open "from" range patterns (`X..`), which will start at `X` and
3333 will end at the maximum value of the integer.][83918]
3334- [You can now explicitly import the prelude of different editions
3335 through `std::prelude` (e.g. `use std::prelude::rust_2021::*;`).][86294]
3336
3337Compiler
3338--------
3339- [Added tier 3\* support for `powerpc64le-unknown-freebsd`.][83572]
3340
3341\* Refer to Rust's [platform support page][platform-support-doc] for more
3342 information on Rust's tiered platform support.
3343
3344Libraries
3345---------
3346
3347- [Updated std's float parsing to use the Eisel-Lemire algorithm.][86761]
3348 These improvements should in general provide faster string parsing of floats,
3349 no longer reject certain valid floating point values, and reduce
3350 the produced code size for non-stripped artifacts.
3351- [`string::Drain` now implements `AsRef<str>` and `AsRef<[u8]>`.][86858]
3352
3353Stabilised APIs
3354---------------
3355
3356- [`Bound::cloned`]
3357- [`Drain::as_str`]
3358- [`IntoInnerError::into_error`]
3359- [`IntoInnerError::into_parts`]
3360- [`MaybeUninit::assume_init_mut`]
3361- [`MaybeUninit::assume_init_ref`]
3362- [`MaybeUninit::write`]
3363- [`array::map`]
3364- [`ops::ControlFlow`]
3365- [`x86::_bittest`]
3366- [`x86::_bittestandcomplement`]
3367- [`x86::_bittestandreset`]
3368- [`x86::_bittestandset`]
3369- [`x86_64::_bittest64`]
3370- [`x86_64::_bittestandcomplement64`]
3371- [`x86_64::_bittestandreset64`]
3372- [`x86_64::_bittestandset64`]
3373
3374The following previously stable functions are now `const`.
3375
3376- [`str::from_utf8_unchecked`]
3377
3378
3379Cargo
3380-----
3381- [Cargo will now deduplicate compiler diagnostics to the terminal when invoking
3382 rustc in parallel such as when using `cargo test`.][cargo/9675]
3383- [The package definition in `cargo metadata` now includes the `"default_run"`
3384 field from the manifest.][cargo/9550]
3385- [Added `cargo d` as an alias for `cargo doc`.][cargo/9680]
3386- [Added `{lib}` as formatting option for `cargo tree` to print the `"lib_name"`
3387 of packages.][cargo/9663]
3388
3389Rustdoc
3390-------
3391- [Added "Go to item on exact match" search option.][85876]
3392- [The "Implementors" section on traits no longer shows redundant
3393 method definitions.][85970]
3394- [Trait implementations are toggled open by default.][86260] This should make the
3395 implementations more searchable by tools like `CTRL+F` in your browser.
3396- [Intra-doc links should now correctly resolve associated items (e.g. methods)
3397 through type aliases.][86334]
3398- [Traits which are marked with `#[doc(hidden)]` will no longer appear in the
3399 "Trait Implementations" section.][86513]
3400
3401
3402Compatibility Notes
3403-------------------
3404- [std functions that return an `io::Error` will no longer use the
3405 `ErrorKind::Other` variant.][85746] This is to better reflect that these
3406 kinds of errors could be categorised [into newer more specific `ErrorKind`
3407 variants][79965], and that they do not represent a user error.
3408- [Using environment variable names with `process::Command` on Windows now
3409 behaves as expected.][85270] Previously using environment variables with
3410 `Command` would cause them to be ASCII-uppercased.
3411- [Rustdoc will now warn on using rustdoc lints that aren't prefixed
3412 with `rustdoc::`][86849]
3413- `RUSTFLAGS` is no longer set for build scripts. Build scripts
3414 should use `CARGO_ENCODED_RUSTFLAGS` instead. See the
3415 [documentation](https://doc.rust-lang.org/nightly/cargo/reference/environment-variables.html#environment-variables-cargo-sets-for-build-scripts)
3416 for more details.
3417
3418[86849]: https://github.com/rust-lang/rust/pull/86849
3419[86513]: https://github.com/rust-lang/rust/pull/86513
3420[86334]: https://github.com/rust-lang/rust/pull/86334
3421[86260]: https://github.com/rust-lang/rust/pull/86260
3422[85970]: https://github.com/rust-lang/rust/pull/85970
3423[85876]: https://github.com/rust-lang/rust/pull/85876
3424[83572]: https://github.com/rust-lang/rust/pull/83572
3425[86294]: https://github.com/rust-lang/rust/pull/86294
3426[86858]: https://github.com/rust-lang/rust/pull/86858
3427[86761]: https://github.com/rust-lang/rust/pull/86761
3428[85746]: https://github.com/rust-lang/rust/pull/85746
3429[85270]: https://github.com/rust-lang/rust/pull/85270
3430[83918]: https://github.com/rust-lang/rust/pull/83918
3431[79965]: https://github.com/rust-lang/rust/pull/79965
3432[cargo/9663]: https://github.com/rust-lang/cargo/pull/9663
3433[cargo/9675]: https://github.com/rust-lang/cargo/pull/9675
3434[cargo/9550]: https://github.com/rust-lang/cargo/pull/9550
3435[cargo/9680]: https://github.com/rust-lang/cargo/pull/9680
3436[`array::map`]: https://doc.rust-lang.org/stable/std/primitive.array.html#method.map
3437[`Bound::cloned`]: https://doc.rust-lang.org/stable/std/ops/enum.Bound.html#method.cloned
3438[`Drain::as_str`]: https://doc.rust-lang.org/stable/std/string/struct.Drain.html#method.as_str
3439[`IntoInnerError::into_error`]: https://doc.rust-lang.org/stable/std/io/struct.IntoInnerError.html#method.into_error
3440[`IntoInnerError::into_parts`]: https://doc.rust-lang.org/stable/std/io/struct.IntoInnerError.html#method.into_parts
3441[`MaybeUninit::assume_init_mut`]: https://doc.rust-lang.org/stable/std/mem/union.MaybeUninit.html#method.assume_init_mut
3442[`MaybeUninit::assume_init_ref`]: https://doc.rust-lang.org/stable/std/mem/union.MaybeUninit.html#method.assume_init_ref
3443[`MaybeUninit::write`]: https://doc.rust-lang.org/stable/std/mem/union.MaybeUninit.html#method.write
3444[`ops::ControlFlow`]: https://doc.rust-lang.org/stable/std/ops/enum.ControlFlow.html
3445[`str::from_utf8_unchecked`]: https://doc.rust-lang.org/stable/std/str/fn.from_utf8_unchecked.html
3446[`x86::_bittest`]: https://doc.rust-lang.org/stable/core/arch/x86/fn._bittest.html
3447[`x86::_bittestandcomplement`]: https://doc.rust-lang.org/stable/core/arch/x86/fn._bittestandcomplement.html
3448[`x86::_bittestandreset`]: https://doc.rust-lang.org/stable/core/arch/x86/fn._bittestandreset.html
3449[`x86::_bittestandset`]: https://doc.rust-lang.org/stable/core/arch/x86/fn._bittestandset.html
3450[`x86_64::_bittest64`]: https://doc.rust-lang.org/stable/core/arch/x86_64/fn._bittest64.html
3451[`x86_64::_bittestandcomplement64`]: https://doc.rust-lang.org/stable/core/arch/x86_64/fn._bittestandcomplement64.html
3452[`x86_64::_bittestandreset64`]: https://doc.rust-lang.org/stable/core/arch/x86_64/fn._bittestandreset64.html
3453[`x86_64::_bittestandset64`]: https://doc.rust-lang.org/stable/core/arch/x86_64/fn._bittestandset64.html
3454
3455
3456Version 1.54.0 (2021-07-29)
3457============================
3458
3459Language
3460-----------------------
3461
3462- [You can now use macros for values in some built-in attributes.][83366]
3463 This primarily allows you to call macros within the `#[doc]` attribute. For
3464 example, to include external documentation in your crate, you can now write
3465 the following:
3466 ```rust
3467 #![doc = include_str!("README.md")]
3468 ```
3469
3470- [You can now cast between unsized slice types (and types which contain
3471 unsized slices) in `const fn`.][85078]
3472- [You can now use multiple generic lifetimes with `impl Trait` where the
3473 lifetimes don't explicitly outlive another.][84701] In code this means
3474 that you can now have `impl Trait<'a, 'b>` where as before you could
3475 only have `impl Trait<'a, 'b> where 'b: 'a`.
3476
3477Compiler
3478-----------------------
3479
3480- [Rustc will now search for custom JSON targets in
3481 `/lib/rustlib/<target-triple>/target.json` where `/` is the "sysroot"
3482 directory.][83800] You can find your sysroot directory by running
3483 `rustc --print sysroot`.
3484- [Added `wasm` as a `target_family` for WebAssembly platforms.][84072]
3485- [You can now use `#[target_feature]` on safe functions when targeting
3486 WebAssembly platforms.][84988]
3487- [Improved debugger output for enums on Windows MSVC platforms.][85292]
3488- [Added tier 3\* support for `bpfel-unknown-none`
3489 and `bpfeb-unknown-none`.][79608]
3490- [`-Zmutable-noalias=yes`][82834] is enabled by default when using LLVM 12 or above.
3491
3492\* Refer to Rust's [platform support page][platform-support-doc] for more
3493 information on Rust's tiered platform support.
3494
3495Libraries
3496-----------------------
3497
3498- [`panic::panic_any` will now `#[track_caller]`.][85745]
3499- [Added `OutOfMemory` as a variant of `io::ErrorKind`.][84744]
3500- [ `proc_macro::Literal` now implements `FromStr`.][84717]
3501- [The implementations of vendor intrinsics in core::arch have been
3502 significantly refactored.][83278] The main user-visible changes are
3503 a 50% reduction in the size of libcore.rlib and stricter validation
3504 of constant operands passed to intrinsics. The latter is technically
3505 a breaking change, but allows Rust to more closely match the C vendor
3506 intrinsics API.
3507
3508Stabilized APIs
3509---------------
3510
3511- [`BTreeMap::into_keys`]
3512- [`BTreeMap::into_values`]
3513- [`HashMap::into_keys`]
3514- [`HashMap::into_values`]
3515- [`arch::wasm32`]
3516- [`VecDeque::binary_search`]
3517- [`VecDeque::binary_search_by`]
3518- [`VecDeque::binary_search_by_key`]
3519- [`VecDeque::partition_point`]
3520
3521Cargo
3522-----
3523
3524- [Added the `--prune <spec>` option to `cargo-tree` to remove a package from
3525 the dependency graph.][cargo/9520]
3526- [Added the `--depth` option to `cargo-tree` to print only to a certain depth
3527 in the tree ][cargo/9499]
3528- [Added the `no-proc-macro` value to `cargo-tree --edges` to hide procedural
3529 macro dependencies.][cargo/9488]
3530- [A new environment variable named `CARGO_TARGET_TMPDIR` is available.][cargo/9375]
3531 This variable points to a directory that integration tests and benches
3532 can use as a "scratchpad" for testing filesystem operations.
3533
3534Compatibility Notes
3535-------------------
3536- [Mixing Option and Result via `?` is no longer permitted in closures for inferred types.][86831]
3537- [Previously unsound code is no longer permitted where different constructors in branches
3538 could require different lifetimes.][85574]
3539- As previously mentioned the [`std::arch` intrinsics now uses stricter const checking][83278]
3540 than before and may reject some previously accepted code.
3541- [`i128` multiplication on Cortex M0+ platforms currently unconditionally causes overflow
3542 when compiled with `codegen-units = 1`.][86063]
3543
3544[85574]: https://github.com/rust-lang/rust/issues/85574
3545[86831]: https://github.com/rust-lang/rust/issues/86831
3546[86063]: https://github.com/rust-lang/rust/issues/86063
3547[79608]: https://github.com/rust-lang/rust/pull/79608
3548[84988]: https://github.com/rust-lang/rust/pull/84988
3549[84701]: https://github.com/rust-lang/rust/pull/84701
3550[84072]: https://github.com/rust-lang/rust/pull/84072
3551[85745]: https://github.com/rust-lang/rust/pull/85745
3552[84744]: https://github.com/rust-lang/rust/pull/84744
3553[85078]: https://github.com/rust-lang/rust/pull/85078
3554[84717]: https://github.com/rust-lang/rust/pull/84717
3555[83800]: https://github.com/rust-lang/rust/pull/83800
3556[83366]: https://github.com/rust-lang/rust/pull/83366
3557[83278]: https://github.com/rust-lang/rust/pull/83278
3558[85292]: https://github.com/rust-lang/rust/pull/85292
3559[82834]: https://github.com/rust-lang/rust/pull/82834
3560[cargo/9520]: https://github.com/rust-lang/cargo/pull/9520
3561[cargo/9499]: https://github.com/rust-lang/cargo/pull/9499
3562[cargo/9488]: https://github.com/rust-lang/cargo/pull/9488
3563[cargo/9375]: https://github.com/rust-lang/cargo/pull/9375
3564[`BTreeMap::into_keys`]: https://doc.rust-lang.org/std/collections/struct.BTreeMap.html#method.into_keys
3565[`BTreeMap::into_values`]: https://doc.rust-lang.org/std/collections/struct.BTreeMap.html#method.into_values
3566[`HashMap::into_keys`]: https://doc.rust-lang.org/std/collections/struct.HashMap.html#method.into_keys
3567[`HashMap::into_values`]: https://doc.rust-lang.org/std/collections/struct.HashMap.html#method.into_values
3568[`arch::wasm32`]: https://doc.rust-lang.org/core/arch/wasm32/index.html
3569[`VecDeque::binary_search`]: https://doc.rust-lang.org/std/collections/struct.VecDeque.html#method.binary_search
3570[`VecDeque::binary_search_by`]: https://doc.rust-lang.org/std/collections/struct.VecDeque.html#method.binary_search_by
3571
3572[`VecDeque::binary_search_by_key`]: https://doc.rust-lang.org/std/collections/struct.VecDeque.html#method.binary_search_by_key
3573
3574[`VecDeque::partition_point`]: https://doc.rust-lang.org/std/collections/struct.VecDeque.html#method.partition_point
3575
3576Version 1.53.0 (2021-06-17)
3577============================
3578
3579Language
3580-----------------------
3581- [You can now use unicode for identifiers.][83799] This allows multilingual
3582 identifiers but still doesn't allow glyphs that are not considered characters
3583 such as `◆` or `🦀`. More specifically you can now use any identifier that
3584 matches the UAX #31 "Unicode Identifier and Pattern Syntax" standard. This
3585 is the same standard as languages like Python, however Rust uses NFC
3586 normalization which may be different from other languages.
3587- [You can now specify "or patterns" inside pattern matches.][79278]
3588 Previously you could only use `|` (OR) on complete patterns. E.g.
3589 ```rust
3590 let x = Some(2u8);
3591 // Before
3592 matches!(x, Some(1) | Some(2));
3593 // Now
3594 matches!(x, Some(1 | 2));
3595 ```
3596- [Added the `:pat_param` `macro_rules!` matcher.][83386] This matcher
3597 has the same semantics as the `:pat` matcher. This is to allow `:pat`
3598 to change semantics to being a pattern fragment in a future edition.
3599
3600Compiler
3601-----------------------
3602- [Updated the minimum external LLVM version to LLVM 10.][83387]
3603- [Added Tier 3\* support for the `wasm64-unknown-unknown` target.][80525]
3604- [Improved debuginfo for closures and async functions on Windows MSVC.][83941]
3605
3606\* Refer to Rust's [platform support page][platform-support-doc] for more
3607information on Rust's tiered platform support.
3608
3609Libraries
3610-----------------------
3611- [Abort messages will now forward to `android_set_abort_message` on
3612 Android platforms when available.][81469]
3613- [`slice::IterMut<'_, T>` now implements `AsRef<[T]>`][82771]
3614- [Arrays of any length now implement `IntoIterator`.][84147]
3615 Currently calling `.into_iter()` as a method on an array will
3616 return `impl Iterator<Item=&T>`, but this may change in a
3617 future edition to change `Item` to `T`. Calling `IntoIterator::into_iter`
3618 directly on arrays will provide `impl Iterator<Item=T>` as expected.
3619- [`leading_zeros`, and `trailing_zeros` are now available on all
3620 `NonZero` integer types.][84082]
3621- [`{f32, f64}::from_str` now parse and print special values
3622 (`NaN`, `-0`) according to IEEE 754.][78618]
3623- [You can now index into slices using `(Bound<usize>, Bound<usize>)`.][77704]
3624- [Add the `BITS` associated constant to all numeric types.][82565]
3625
3626Stabilised APIs
3627---------------
3628- [`AtomicBool::fetch_update`]
3629- [`AtomicPtr::fetch_update`]
3630- [`BTreeMap::retain`]
3631- [`BTreeSet::retain`]
3632- [`BufReader::seek_relative`]
3633- [`DebugStruct::non_exhaustive`]
3634- [`Duration::MAX`]
3635- [`Duration::ZERO`]
3636- [`Duration::is_zero`]
3637- [`Duration::saturating_add`]
3638- [`Duration::saturating_mul`]
3639- [`Duration::saturating_sub`]
3640- [`ErrorKind::Unsupported`]
3641- [`Option::insert`]
3642- [`Ordering::is_eq`]
3643- [`Ordering::is_ge`]
3644- [`Ordering::is_gt`]
3645- [`Ordering::is_le`]
3646- [`Ordering::is_lt`]
3647- [`Ordering::is_ne`]
3648- [`OsStr::is_ascii`]
3649- [`OsStr::make_ascii_lowercase`]
3650- [`OsStr::make_ascii_uppercase`]
3651- [`OsStr::to_ascii_lowercase`]
3652- [`OsStr::to_ascii_uppercase`]
3653- [`Peekable::peek_mut`]
3654- [`Rc::decrement_strong_count`]
3655- [`Rc::increment_strong_count`]
3656- [`Vec::extend_from_within`]
3657- [`array::from_mut`]
3658- [`array::from_ref`]
3659- [`cmp::max_by_key`]
3660- [`cmp::max_by`]
3661- [`cmp::min_by_key`]
3662- [`cmp::min_by`]
3663- [`f32::is_subnormal`]
3664- [`f64::is_subnormal`]
3665
3666Cargo
3667-----------------------
3668- [Cargo now supports git repositories where the default `HEAD` branch is not
3669 "master".][cargo/9392] This also includes a switch to the version 3 `Cargo.lock` format
3670 which can handle default branches correctly.
3671- [macOS targets now default to `unpacked` split-debuginfo.][cargo/9298]
3672- [The `authors` field is no longer included in `Cargo.toml` for new
3673 projects.][cargo/9282]
3674
3675Rustdoc
3676-----------------------
3677- [Added the `rustdoc::bare_urls` lint that warns when you have URLs
3678 without hyperlinks.][81764]
3679
3680Compatibility Notes
3681-------------------
3682- [Implement token-based handling of attributes during expansion][82608]
3683- [`Ipv4::from_str` will now reject octal format IP addresses in addition
3684 to rejecting hexadecimal IP addresses.][83652] The octal format can lead
3685 to confusion and potential security vulnerabilities and [is no
3686 longer recommended][ietf6943].
3687- [The added `BITS` constant may conflict with external definitions.][85667]
3688 In particular, this was known to be a problem in the `lexical-core` crate,
3689 but they have published fixes for semantic versions 0.4 through 0.7. To
3690 update this dependency alone, use `cargo update -p lexical-core`.
3691- Incremental compilation remains off by default, unless one uses the `RUSTC_FORCE_INCREMENTAL=1` environment variable added in 1.52.1.
3692
3693Internal Only
3694-------------
3695These changes provide no direct user facing benefits, but represent significant
3696improvements to the internals and overall performance of rustc and
3697related tools.
3698
3699- [Rework the `std::sys::windows::alloc` implementation.][83065]
3700- [rustdoc: Don't enter an infer_ctxt in get_blanket_impls for impls that aren't blanket impls.][82864]
3701- [rustdoc: Only look at blanket impls in `get_blanket_impls`][83681]
3702- [Rework rustdoc const type][82873]
3703
3704[85667]: https://github.com/rust-lang/rust/pull/85667
3705[83386]: https://github.com/rust-lang/rust/pull/83386
3706[82771]: https://github.com/rust-lang/rust/pull/82771
3707[84147]: https://github.com/rust-lang/rust/pull/84147
3708[84082]: https://github.com/rust-lang/rust/pull/84082
3709[83799]: https://github.com/rust-lang/rust/pull/83799
3710[83681]: https://github.com/rust-lang/rust/pull/83681
3711[83652]: https://github.com/rust-lang/rust/pull/83652
3712[83387]: https://github.com/rust-lang/rust/pull/83387
3713[82873]: https://github.com/rust-lang/rust/pull/82873
3714[82864]: https://github.com/rust-lang/rust/pull/82864
3715[82608]: https://github.com/rust-lang/rust/pull/82608
3716[82565]: https://github.com/rust-lang/rust/pull/82565
3717[80525]: https://github.com/rust-lang/rust/pull/80525
3718[79278]: https://github.com/rust-lang/rust/pull/79278
3719[78618]: https://github.com/rust-lang/rust/pull/78618
3720[77704]: https://github.com/rust-lang/rust/pull/77704
3721[83941]: https://github.com/rust-lang/rust/pull/83941
3722[83065]: https://github.com/rust-lang/rust/pull/83065
3723[81764]: https://github.com/rust-lang/rust/pull/81764
3724[81469]: https://github.com/rust-lang/rust/pull/81469
3725[cargo/9298]: https://github.com/rust-lang/cargo/pull/9298
3726[cargo/9282]: https://github.com/rust-lang/cargo/pull/9282
3727[cargo/9392]: https://github.com/rust-lang/cargo/pull/9392
3728[`AtomicBool::fetch_update`]: https://doc.rust-lang.org/std/sync/atomic/struct.AtomicBool.html#method.fetch_update
3729[`AtomicPtr::fetch_update`]: https://doc.rust-lang.org/std/sync/atomic/struct.AtomicPtr.html#method.fetch_update
3730[`BTreeMap::retain`]: https://doc.rust-lang.org/std/collections/struct.BTreeMap.html#method.retain
3731[`BTreeSet::retain`]: https://doc.rust-lang.org/std/collections/struct.BTreeSet.html#method.retain
3732[`BufReader::seek_relative`]: https://doc.rust-lang.org/std/io/struct.BufReader.html#method.seek_relative
3733[`DebugStruct::non_exhaustive`]: https://doc.rust-lang.org/std/fmt/struct.DebugStruct.html#method.finish_non_exhaustive
3734[`Duration::MAX`]: https://doc.rust-lang.org/std/time/struct.Duration.html#associatedconstant.MAX
3735[`Duration::ZERO`]: https://doc.rust-lang.org/std/time/struct.Duration.html#associatedconstant.ZERO
3736[`Duration::is_zero`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.is_zero
3737[`Duration::saturating_add`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.saturating_add
3738[`Duration::saturating_mul`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.saturating_mul
3739[`Duration::saturating_sub`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.saturating_sub
3740[`ErrorKind::Unsupported`]: https://doc.rust-lang.org/std/io/enum.ErrorKind.html#variant.Unsupported
3741[`Option::insert`]: https://doc.rust-lang.org/std/option/enum.Option.html#method.insert
3742[`Ordering::is_eq`]: https://doc.rust-lang.org/std/cmp/enum.Ordering.html#method.is_eq
3743[`Ordering::is_ge`]: https://doc.rust-lang.org/std/cmp/enum.Ordering.html#method.is_ge
3744[`Ordering::is_gt`]: https://doc.rust-lang.org/std/cmp/enum.Ordering.html#method.is_gt
3745[`Ordering::is_le`]: https://doc.rust-lang.org/std/cmp/enum.Ordering.html#method.is_le
3746[`Ordering::is_lt`]: https://doc.rust-lang.org/std/cmp/enum.Ordering.html#method.is_lt
3747[`Ordering::is_ne`]: https://doc.rust-lang.org/std/cmp/enum.Ordering.html#method.is_ne
3748[`OsStr::is_ascii`]: https://doc.rust-lang.org/std/ffi/struct.OsStr.html#method.is_ascii
3749[`OsStr::make_ascii_lowercase`]: https://doc.rust-lang.org/std/ffi/struct.OsStr.html#method.make_ascii_lowercase
3750[`OsStr::make_ascii_uppercase`]: https://doc.rust-lang.org/std/ffi/struct.OsStr.html#method.make_ascii_uppercase
3751[`OsStr::to_ascii_lowercase`]: https://doc.rust-lang.org/std/ffi/struct.OsStr.html#method.to_ascii_lowercase
3752[`OsStr::to_ascii_uppercase`]: https://doc.rust-lang.org/std/ffi/struct.OsStr.html#method.to_ascii_uppercase
3753[`Peekable::peek_mut`]: https://doc.rust-lang.org/std/iter/struct.Peekable.html#method.peek_mut
3754[`Rc::decrement_strong_count`]: https://doc.rust-lang.org/std/rc/struct.Rc.html#method.decrement_strong_count
3755[`Rc::increment_strong_count`]: https://doc.rust-lang.org/std/rc/struct.Rc.html#method.increment_strong_count
3756[`Vec::extend_from_within`]: https://doc.rust-lang.org/beta/std/vec/struct.Vec.html#method.extend_from_within
3757[`array::from_mut`]: https://doc.rust-lang.org/beta/std/array/fn.from_mut.html
3758[`array::from_ref`]: https://doc.rust-lang.org/beta/std/array/fn.from_ref.html
3759[`cmp::max_by_key`]: https://doc.rust-lang.org/beta/std/cmp/fn.max_by_key.html
3760[`cmp::max_by`]: https://doc.rust-lang.org/beta/std/cmp/fn.max_by.html
3761[`cmp::min_by_key`]: https://doc.rust-lang.org/beta/std/cmp/fn.min_by_key.html
3762[`cmp::min_by`]: https://doc.rust-lang.org/beta/std/cmp/fn.min_by.html
3763[`f32::is_subnormal`]: https://doc.rust-lang.org/std/primitive.f32.html#method.is_subnormal
3764[`f64::is_subnormal`]: https://doc.rust-lang.org/std/primitive.f64.html#method.is_subnormal
3765[ietf6943]: https://datatracker.ietf.org/doc/html/rfc6943#section-3.1.1
3766
3767
3768Version 1.52.1 (2021-05-10)
3769============================
3770
3771This release disables incremental compilation, unless the user has explicitly
3772opted in via the newly added RUSTC_FORCE_INCREMENTAL=1 environment variable.
3773
3774This is due to the widespread, and frequently occurring, breakage encountered by
3775Rust users due to newly enabled incremental verification in 1.52.0. Notably,
3776Rust users **should** upgrade to 1.52.0 or 1.52.1: the bugs that are detected by
3777newly added incremental verification are still present in past stable versions,
3778and are not yet fixed on any channel. These bugs can lead to miscompilation of
3779Rust binaries.
3780
3781These problems only affect incremental builds, so release builds with Cargo
3782should not be affected unless the user has explicitly opted into incremental.
3783Debug and check builds are affected.
3784
3785See [84970] for more details.
3786
3787[84970]: https://github.com/rust-lang/rust/issues/84970
3788
3789Version 1.52.0 (2021-05-06)
3790============================
3791
3792Language
3793--------
3794- [Added the `unsafe_op_in_unsafe_fn` lint, which checks whether the unsafe code
3795 in an `unsafe fn` is wrapped in a `unsafe` block.][79208] This lint
3796 is allowed by default, and may become a warning or hard error in a
3797 future edition.
3798- [You can now cast mutable references to arrays to a pointer of the same type as
3799 the element.][81479]
3800
3801Compiler
3802--------
3803- [Upgraded the default LLVM to LLVM 12.][81451]
3804
3805Added tier 3\* support for the following targets.
3806
3807- [`s390x-unknown-linux-musl`][82166]
3808- [`riscv32gc-unknown-linux-musl` & `riscv64gc-unknown-linux-musl`][82202]
3809- [`powerpc-unknown-openbsd`][82733]
3810
3811\* Refer to Rust's [platform support page][platform-support-doc] for more
3812information on Rust's tiered platform support.
3813
3814Libraries
3815---------
3816- [`OsString` now implements `Extend` and `FromIterator`.][82121]
3817- [`cmp::Reverse` now has `#[repr(transparent)]` representation.][81879]
3818- [`Arc<impl Error>` now implements `error::Error`.][80553]
3819- [All integer division and remainder operations are now `const`.][80962]
3820
3821Stabilised APIs
3822-------------
3823- [`Arguments::as_str`]
3824- [`char::MAX`]
3825- [`char::REPLACEMENT_CHARACTER`]
3826- [`char::UNICODE_VERSION`]
3827- [`char::decode_utf16`]
3828- [`char::from_digit`]
3829- [`char::from_u32_unchecked`]
3830- [`char::from_u32`]
3831- [`slice::partition_point`]
3832- [`str::rsplit_once`]
3833- [`str::split_once`]
3834
3835The following previously stable APIs are now `const`.
3836
3837- [`char::len_utf8`]
3838- [`char::len_utf16`]
3839- [`char::to_ascii_uppercase`]
3840- [`char::to_ascii_lowercase`]
3841- [`char::eq_ignore_ascii_case`]
3842- [`u8::to_ascii_uppercase`]
3843- [`u8::to_ascii_lowercase`]
3844- [`u8::eq_ignore_ascii_case`]
3845
3846Rustdoc
3847-------
3848- [Rustdoc lints are now treated as a tool lint, meaning that
3849 lints are now prefixed with `rustdoc::` (e.g. `#[warn(rustdoc::broken_intra_doc_links)]`).][80527]
3850 Using the old style is still allowed, and will become a warning in
3851 a future release.
3852- [Rustdoc now supports argument files.][82261]
3853- [Rustdoc now generates smart punctuation for documentation.][79423]
3854- [You can now use "task lists" in Rustdoc Markdown.][81766] E.g.
3855 ```markdown
3856 - [x] Complete
3857 - [ ] Todo
3858 ```
3859
3860Misc
3861----
3862- [You can now pass multiple filters to tests.][81356] E.g.
3863 `cargo test -- foo bar` will run all tests that match `foo` and `bar`.
3864- [Rustup now distributes PDB symbols for the `std` library on Windows,
3865 allowing you to see `std` symbols when debugging.][82218]
3866
3867Internal Only
3868-------------
3869These changes provide no direct user facing benefits, but represent significant
3870improvements to the internals and overall performance of rustc and
3871related tools.
3872
3873- [Check the result cache before the DepGraph when ensuring queries][81855]
3874- [Try fast_reject::simplify_type in coherence before doing full check][81744]
3875- [Only store a LocalDefId in some HIR nodes][81611]
3876- [Store HIR attributes in a side table][79519]
3877
3878Compatibility Notes
3879-------------------
3880- [Cargo build scripts are now forbidden from setting `RUSTC_BOOTSTRAP`.][cargo/9181]
3881- [Removed support for the `x86_64-rumprun-netbsd` target.][82594]
3882- [Deprecated the `x86_64-sun-solaris` target in favor of `x86_64-pc-solaris`.][82216]
3883- [Rustdoc now only accepts `,`, ` `, and `\t` as delimiters for specifying
3884 languages in code blocks.][78429]
3885- [Rustc now catches more cases of `pub_use_of_private_extern_crate`][80763]
3886- [Changes in how proc macros handle whitespace may lead to panics when used
3887 with older `proc-macro-hack` versions. A `cargo update` should be sufficient to fix this in all cases.][84136]
3888- [Turn `#[derive]` into a regular macro attribute][79078]
3889
3890[84136]: https://github.com/rust-lang/rust/issues/84136
3891[80763]: https://github.com/rust-lang/rust/pull/80763
3892[82166]: https://github.com/rust-lang/rust/pull/82166
3893[82121]: https://github.com/rust-lang/rust/pull/82121
3894[81879]: https://github.com/rust-lang/rust/pull/81879
3895[82261]: https://github.com/rust-lang/rust/pull/82261
3896[82218]: https://github.com/rust-lang/rust/pull/82218
3897[82216]: https://github.com/rust-lang/rust/pull/82216
3898[82202]: https://github.com/rust-lang/rust/pull/82202
3899[81855]: https://github.com/rust-lang/rust/pull/81855
3900[81766]: https://github.com/rust-lang/rust/pull/81766
3901[81744]: https://github.com/rust-lang/rust/pull/81744
3902[81611]: https://github.com/rust-lang/rust/pull/81611
3903[81479]: https://github.com/rust-lang/rust/pull/81479
3904[81451]: https://github.com/rust-lang/rust/pull/81451
3905[81356]: https://github.com/rust-lang/rust/pull/81356
3906[80962]: https://github.com/rust-lang/rust/pull/80962
3907[80553]: https://github.com/rust-lang/rust/pull/80553
3908[80527]: https://github.com/rust-lang/rust/pull/80527
3909[79519]: https://github.com/rust-lang/rust/pull/79519
3910[79423]: https://github.com/rust-lang/rust/pull/79423
3911[79208]: https://github.com/rust-lang/rust/pull/79208
3912[78429]: https://github.com/rust-lang/rust/pull/78429
3913[82733]: https://github.com/rust-lang/rust/pull/82733
3914[82594]: https://github.com/rust-lang/rust/pull/82594
3915[79078]: https://github.com/rust-lang/rust/pull/79078
3916[cargo/9181]: https://github.com/rust-lang/cargo/pull/9181
3917[`char::MAX`]: https://doc.rust-lang.org/std/primitive.char.html#associatedconstant.MAX
3918[`char::REPLACEMENT_CHARACTER`]: https://doc.rust-lang.org/std/primitive.char.html#associatedconstant.REPLACEMENT_CHARACTER
3919[`char::UNICODE_VERSION`]: https://doc.rust-lang.org/std/primitive.char.html#associatedconstant.UNICODE_VERSION
3920[`char::decode_utf16`]: https://doc.rust-lang.org/std/primitive.char.html#method.decode_utf16
3921[`char::from_u32`]: https://doc.rust-lang.org/std/primitive.char.html#method.from_u32
3922[`char::from_u32_unchecked`]: https://doc.rust-lang.org/std/primitive.char.html#method.from_u32_unchecked
3923[`char::from_digit`]: https://doc.rust-lang.org/std/primitive.char.html#method.from_digit
3924[`Peekable::next_if`]: https://doc.rust-lang.org/stable/std/iter/struct.Peekable.html#method.next_if
3925[`Peekable::next_if_eq`]: https://doc.rust-lang.org/stable/std/iter/struct.Peekable.html#method.next_if_eq
3926[`Arguments::as_str`]: https://doc.rust-lang.org/stable/std/fmt/struct.Arguments.html#method.as_str
3927[`str::split_once`]: https://doc.rust-lang.org/stable/std/primitive.str.html#method.split_once
3928[`str::rsplit_once`]: https://doc.rust-lang.org/stable/std/primitive.str.html#method.rsplit_once
3929[`slice::partition_point`]: https://doc.rust-lang.org/stable/std/primitive.slice.html#method.partition_point
3930[`char::len_utf8`]: https://doc.rust-lang.org/stable/std/primitive.char.html#method.len_utf8
3931[`char::len_utf16`]: https://doc.rust-lang.org/stable/std/primitive.char.html#method.len_utf16
3932[`char::to_ascii_uppercase`]: https://doc.rust-lang.org/stable/std/primitive.char.html#method.to_ascii_uppercase
3933[`char::to_ascii_lowercase`]: https://doc.rust-lang.org/stable/std/primitive.char.html#method.to_ascii_lowercase
3934[`char::eq_ignore_ascii_case`]: https://doc.rust-lang.org/stable/std/primitive.char.html#method.eq_ignore_ascii_case
3935[`u8::to_ascii_uppercase`]: https://doc.rust-lang.org/stable/std/primitive.u8.html#method.to_ascii_uppercase
3936[`u8::to_ascii_lowercase`]: https://doc.rust-lang.org/stable/std/primitive.u8.html#method.to_ascii_lowercase
3937[`u8::eq_ignore_ascii_case`]: https://doc.rust-lang.org/stable/std/primitive.u8.html#method.eq_ignore_ascii_case
3938
3939Version 1.51.0 (2021-03-25)
3940============================
3941
3942Language
3943--------
3944- [You can now parameterize items such as functions, traits, and `struct`s by constant
3945 values in addition to by types and lifetimes.][79135] Also known as "const generics"
3946 E.g. you can now write the following. Note: Only values of primitive integers,
3947 `bool`, or `char` types are currently permitted.
3948 ```rust
3949 struct GenericArray<T, const LENGTH: usize> {
3950 inner: [T; LENGTH]
3951 }
3952
3953 impl<T, const LENGTH: usize> GenericArray<T, LENGTH> {
3954 const fn last(&self) -> Option<&T> {
3955 if LENGTH == 0 {
3956 None
3957 } else {
3958 Some(&self.inner[LENGTH - 1])
3959 }
3960 }
3961 }
3962 ```
3963
3964
3965Compiler
3966--------
3967
3968- [Added the `-Csplit-debuginfo` codegen option for macOS platforms.][79570]
3969 This option controls whether debug information is split across multiple files
3970 or packed into a single file. **Note** This option is unstable on other platforms.
3971- [Added tier 3\* support for `aarch64_be-unknown-linux-gnu`,
3972 `aarch64-unknown-linux-gnu_ilp32`, and `aarch64_be-unknown-linux-gnu_ilp32` targets.][81455]
3973- [Added tier 3 support for `i386-unknown-linux-gnu` and `i486-unknown-linux-gnu` targets.][80662]
3974- [The `target-cpu=native` option will now detect individual features of CPUs.][80749]
3975
3976\* Refer to Rust's [platform support page][platform-support-doc] for more
3977information on Rust's tiered platform support.
3978
3979Libraries
3980---------
3981
3982- [`Box::downcast` is now also implemented for any `dyn Any + Send + Sync` object.][80945]
3983- [`str` now implements `AsMut<str>`.][80279]
3984- [`u64` and `u128` now implement `From<char>`.][79502]
3985- [`Error` is now implemented for `&T` where `T` implements `Error`.][75180]
3986- [`Poll::{map_ok, map_err}` are now implemented for `Poll<Option<Result<T, E>>>`.][80968]
3987- [`unsigned_abs` is now implemented for all signed integer types.][80959]
3988- [`io::Empty` now implements `io::Seek`.][78044]
3989- [`rc::Weak<T>` and `sync::Weak<T>`'s methods such as `as_ptr` are now implemented for
3990 `T: ?Sized` types.][80764]
3991- [`Div` and `Rem` by their `NonZero` variant is now implemented for all unsigned integers.][79134]
3992
3993
3994Stabilized APIs
3995---------------
3996
3997- [`Arc::decrement_strong_count`]
3998- [`Arc::increment_strong_count`]
3999- [`Once::call_once_force`]
4000- [`Peekable::next_if_eq`]
4001- [`Peekable::next_if`]
4002- [`Seek::stream_position`]
4003- [`array::IntoIter`]
4004- [`panic::panic_any`]
4005- [`ptr::addr_of!`]
4006- [`ptr::addr_of_mut!`]
4007- [`slice::fill_with`]
4008- [`slice::split_inclusive_mut`]
4009- [`slice::split_inclusive`]
4010- [`slice::strip_prefix`]
4011- [`slice::strip_suffix`]
4012- [`str::split_inclusive`]
4013- [`sync::OnceState`]
4014- [`task::Wake`]
4015- [`VecDeque::range`]
4016- [`VecDeque::range_mut`]
4017
4018Cargo
4019-----
4020- [Added the `split-debuginfo` profile option to control the -Csplit-debuginfo
4021 codegen option.][cargo/9112]
4022- [Added the `resolver` field to `Cargo.toml` to enable the new feature resolver
4023 and CLI option behavior.][cargo/8997] Version 2 of the feature resolver will try
4024 to avoid unifying features of dependencies where that unification could be unwanted.
4025 Such as using the same dependency with a `std` feature in a build scripts and
4026 proc-macros, while using the `no-std` feature in the final binary. See the
4027 [Cargo book documentation][feature-resolver@2.0] for more information on the feature.
4028
4029Rustdoc
4030-------
4031
4032- [Rustdoc will now include documentation for methods available from _nested_ `Deref` traits.][80653]
4033- [You can now provide a `--default-theme` flag which sets the default theme to use for
4034 documentation.][79642]
4035
4036Various improvements to intra-doc links:
4037
4038- [You can link to non-path primitives such as `slice`.][80181]
4039- [You can link to associated items.][74489]
4040- [You can now include generic parameters when linking to items, like `Vec<T>`.][76934]
4041
4042Misc
4043----
4044- [You can now pass `--include-ignored` to tests (e.g. with
4045 `cargo test -- --include-ignored`) to include testing tests marked `#[ignore]`.][80053]
4046
4047Compatibility Notes
4048-------------------
4049
4050- [WASI platforms no longer use the `wasm-bindgen` ABI, and instead use the wasm32 ABI.][79998]
4051- [`rustc` no longer promotes division, modulo and indexing operations to `const` that
4052 could fail.][80579]
4053- [The minimum version of glibc for the following platforms has been bumped to version 2.31
4054 for the distributed artifacts.][81521]
4055 - `armv5te-unknown-linux-gnueabi`
4056 - `sparc64-unknown-linux-gnu`
4057 - `thumbv7neon-unknown-linux-gnueabihf`
4058 - `armv7-unknown-linux-gnueabi`
4059 - `x86_64-unknown-linux-gnux32`
4060- [`atomic::spin_loop_hint` has been deprecated.][80966] It's recommended to use `hint::spin_loop` instead.
4061
4062Internal Only
4063-------------
4064
4065- [Consistently avoid constructing optimized MIR when not doing codegen][80718]
4066
4067[79135]: https://github.com/rust-lang/rust/pull/79135
4068[74489]: https://github.com/rust-lang/rust/pull/74489
4069[76934]: https://github.com/rust-lang/rust/pull/76934
4070[79570]: https://github.com/rust-lang/rust/pull/79570
4071[80181]: https://github.com/rust-lang/rust/pull/80181
4072[79642]: https://github.com/rust-lang/rust/pull/79642
4073[80945]: https://github.com/rust-lang/rust/pull/80945
4074[80279]: https://github.com/rust-lang/rust/pull/80279
4075[80053]: https://github.com/rust-lang/rust/pull/80053
4076[79502]: https://github.com/rust-lang/rust/pull/79502
4077[75180]: https://github.com/rust-lang/rust/pull/75180
4078[81521]: https://github.com/rust-lang/rust/pull/81521
4079[80968]: https://github.com/rust-lang/rust/pull/80968
4080[80959]: https://github.com/rust-lang/rust/pull/80959
4081[80718]: https://github.com/rust-lang/rust/pull/80718
4082[80653]: https://github.com/rust-lang/rust/pull/80653
4083[80579]: https://github.com/rust-lang/rust/pull/80579
4084[79998]: https://github.com/rust-lang/rust/pull/79998
4085[78044]: https://github.com/rust-lang/rust/pull/78044
4086[81455]: https://github.com/rust-lang/rust/pull/81455
4087[80764]: https://github.com/rust-lang/rust/pull/80764
4088[80749]: https://github.com/rust-lang/rust/pull/80749
4089[80662]: https://github.com/rust-lang/rust/pull/80662
4090[79134]: https://github.com/rust-lang/rust/pull/79134
4091[80966]: https://github.com/rust-lang/rust/pull/80966
4092[cargo/8997]: https://github.com/rust-lang/cargo/pull/8997
4093[cargo/9112]: https://github.com/rust-lang/cargo/pull/9112
4094[feature-resolver@2.0]: https://doc.rust-lang.org/nightly/cargo/reference/features.html#feature-resolver-version-2
4095[`Once::call_once_force`]: https://doc.rust-lang.org/stable/std/sync/struct.Once.html#method.call_once_force
4096[`sync::OnceState`]: https://doc.rust-lang.org/stable/std/sync/struct.OnceState.html
4097[`panic::panic_any`]: https://doc.rust-lang.org/stable/std/panic/fn.panic_any.html
4098[`slice::strip_prefix`]: https://doc.rust-lang.org/stable/std/primitive.slice.html#method.strip_prefix
4099[`slice::strip_suffix`]: https://doc.rust-lang.org/stable/std/primitive.slice.html#method.strip_suffix
4100[`Arc::increment_strong_count`]: https://doc.rust-lang.org/nightly/std/sync/struct.Arc.html#method.increment_strong_count
4101[`Arc::decrement_strong_count`]: https://doc.rust-lang.org/nightly/std/sync/struct.Arc.html#method.decrement_strong_count
4102[`slice::fill_with`]: https://doc.rust-lang.org/nightly/std/primitive.slice.html#method.fill_with
4103[`ptr::addr_of!`]: https://doc.rust-lang.org/nightly/std/ptr/macro.addr_of.html
4104[`ptr::addr_of_mut!`]: https://doc.rust-lang.org/nightly/std/ptr/macro.addr_of_mut.html
4105[`array::IntoIter`]: https://doc.rust-lang.org/nightly/std/array/struct.IntoIter.html
4106[`slice::split_inclusive`]: https://doc.rust-lang.org/nightly/std/primitive.slice.html#method.split_inclusive
4107[`slice::split_inclusive_mut`]: https://doc.rust-lang.org/nightly/std/primitive.slice.html#method.split_inclusive_mut
4108[`str::split_inclusive`]: https://doc.rust-lang.org/nightly/std/primitive.str.html#method.split_inclusive
4109[`task::Wake`]: https://doc.rust-lang.org/nightly/std/task/trait.Wake.html
4110[`Seek::stream_position`]: https://doc.rust-lang.org/nightly/std/io/trait.Seek.html#method.stream_position
4111[`Peekable::next_if`]: https://doc.rust-lang.org/nightly/std/iter/struct.Peekable.html#method.next_if
4112[`Peekable::next_if_eq`]: https://doc.rust-lang.org/nightly/std/iter/struct.Peekable.html#method.next_if_eq
4113[`VecDeque::range`]: https://doc.rust-lang.org/nightly/std/collections/struct.VecDeque.html#method.range
4114[`VecDeque::range_mut`]: https://doc.rust-lang.org/nightly/std/collections/struct.VecDeque.html#method.range_mut
4115
4116Version 1.50.0 (2021-02-11)
4117============================
4118
4119Language
4120-----------------------
4121- [You can now use `const` values for `x` in `[x; N]` array expressions.][79270]
4122 This has been technically possible since 1.38.0, as it was unintentionally stabilized.
4123- [Assignments to `ManuallyDrop<T>` union fields are now considered safe.][78068]
4124
4125Compiler
4126-----------------------
4127- [Added tier 3\* support for the `armv5te-unknown-linux-uclibceabi` target.][78142]
4128- [Added tier 3 support for the `aarch64-apple-ios-macabi` target.][77484]
4129- [The `x86_64-unknown-freebsd` is now built with the full toolset.][79484]
4130- [Dropped support for all cloudabi targets.][78439]
4131
4132\* Refer to Rust's [platform support page][platform-support-doc] for more
4133information on Rust's tiered platform support.
4134
4135Libraries
4136-----------------------
4137
4138- [`proc_macro::Punct` now implements `PartialEq<char>`.][78636]
4139- [`ops::{Index, IndexMut}` are now implemented for fixed sized arrays of any length.][74989]
4140- [On Unix platforms, the `std::fs::File` type now has a "niche" of `-1`.][74699]
4141 This value cannot be a valid file descriptor, and now means `Option<File>` takes
4142 up the same amount of space as `File`.
4143
4144Stabilized APIs
4145---------------
4146
4147- [`bool::then`]
4148- [`btree_map::Entry::or_insert_with_key`]
4149- [`f32::clamp`]
4150- [`f64::clamp`]
4151- [`hash_map::Entry::or_insert_with_key`]
4152- [`Ord::clamp`]
4153- [`RefCell::take`]
4154- [`slice::fill`]
4155- [`UnsafeCell::get_mut`]
4156
4157The following previously stable methods are now `const`.
4158
4159- [`IpAddr::is_ipv4`]
4160- [`IpAddr::is_ipv6`]
4161- [`IpAddr::is_unspecified`]
4162- [`IpAddr::is_loopback`]
4163- [`IpAddr::is_multicast`]
4164- [`Ipv4Addr::octets`]
4165- [`Ipv4Addr::is_loopback`]
4166- [`Ipv4Addr::is_private`]
4167- [`Ipv4Addr::is_link_local`]
4168- [`Ipv4Addr::is_multicast`]
4169- [`Ipv4Addr::is_broadcast`]
4170- [`Ipv4Addr::is_documentation`]
4171- [`Ipv4Addr::to_ipv6_compatible`]
4172- [`Ipv4Addr::to_ipv6_mapped`]
4173- [`Ipv6Addr::segments`]
4174- [`Ipv6Addr::is_unspecified`]
4175- [`Ipv6Addr::is_loopback`]
4176- [`Ipv6Addr::is_multicast`]
4177- [`Ipv6Addr::to_ipv4`]
4178- [`Layout::size`]
4179- [`Layout::align`]
4180- [`Layout::from_size_align`]
4181- `pow` for all integer types.
4182- `checked_pow` for all integer types.
4183- `saturating_pow` for all integer types.
4184- `wrapping_pow` for all integer types.
4185- `next_power_of_two` for all unsigned integer types.
4186- `checked_next_power_of_two` for all unsigned integer types.
4187
4188Cargo
4189-----------------------
4190
4191- [Added the `[build.rustc-workspace-wrapper]` option.][cargo/8976]
4192 This option sets a wrapper to execute instead of `rustc`, for workspace members only.
4193- [`cargo:rerun-if-changed` will now, if provided a directory, scan the entire
4194 contents of that directory for changes.][cargo/8973]
4195- [Added the `--workspace` flag to the `cargo update` command.][cargo/8725]
4196
4197Misc
4198----
4199
4200- [The search results tab and the help button are focusable with keyboard in rustdoc.][79896]
4201- [Running tests will now print the total time taken to execute.][75752]
4202
4203Compatibility Notes
4204-------------------
4205
4206- [The `compare_and_swap` method on atomics has been deprecated.][79261] It's
4207 recommended to use the `compare_exchange` and `compare_exchange_weak` methods instead.
4208- [Changes in how `TokenStream`s are checked have fixed some cases where you could write
4209 unhygenic `macro_rules!` macros.][79472]
4210- [`#![test]` as an inner attribute is now considered unstable like other inner macro
4211 attributes, and reports an error by default through the `soft_unstable` lint.][79003]
4212- [Overriding a `forbid` lint at the same level that it was set is now a hard error.][78864]
4213- [You can no longer intercept `panic!` calls by supplying your own macro.][78343] It's
4214 recommended to use the `#[panic_handler]` attribute to provide your own implementation.
4215- [Semi-colons after item statements (e.g. `struct Foo {};`) now produce a warning.][78296]
4216
4217[74989]: https://github.com/rust-lang/rust/pull/74989
4218[79261]: https://github.com/rust-lang/rust/pull/79261
4219[79896]: https://github.com/rust-lang/rust/pull/79896
4220[79484]: https://github.com/rust-lang/rust/pull/79484
4221[79472]: https://github.com/rust-lang/rust/pull/79472
4222[79270]: https://github.com/rust-lang/rust/pull/79270
4223[79003]: https://github.com/rust-lang/rust/pull/79003
4224[78864]: https://github.com/rust-lang/rust/pull/78864
4225[78636]: https://github.com/rust-lang/rust/pull/78636
4226[78439]: https://github.com/rust-lang/rust/pull/78439
4227[78343]: https://github.com/rust-lang/rust/pull/78343
4228[78296]: https://github.com/rust-lang/rust/pull/78296
4229[78068]: https://github.com/rust-lang/rust/pull/78068
4230[75752]: https://github.com/rust-lang/rust/pull/75752
4231[74699]: https://github.com/rust-lang/rust/pull/74699
4232[78142]: https://github.com/rust-lang/rust/pull/78142
4233[77484]: https://github.com/rust-lang/rust/pull/77484
4234[cargo/8976]: https://github.com/rust-lang/cargo/pull/8976
4235[cargo/8973]: https://github.com/rust-lang/cargo/pull/8973
4236[cargo/8725]: https://github.com/rust-lang/cargo/pull/8725
4237[`IpAddr::is_ipv4`]: https://doc.rust-lang.org/stable/std/net/enum.IpAddr.html#method.is_ipv4
4238[`IpAddr::is_ipv6`]: https://doc.rust-lang.org/stable/std/net/enum.IpAddr.html#method.is_ipv6
4239[`IpAddr::is_unspecified`]: https://doc.rust-lang.org/stable/std/net/enum.IpAddr.html#method.is_unspecified
4240[`IpAddr::is_loopback`]: https://doc.rust-lang.org/stable/std/net/enum.IpAddr.html#method.is_loopback
4241[`IpAddr::is_multicast`]: https://doc.rust-lang.org/stable/std/net/enum.IpAddr.html#method.is_multicast
4242[`Ipv4Addr::octets`]: https://doc.rust-lang.org/stable/std/net/struct.Ipv4Addr.html#method.octets
4243[`Ipv4Addr::is_loopback`]: https://doc.rust-lang.org/stable/std/net/struct.Ipv4Addr.html#method.is_loopback
4244[`Ipv4Addr::is_private`]: https://doc.rust-lang.org/stable/std/net/struct.Ipv4Addr.html#method.is_private
4245[`Ipv4Addr::is_link_local`]: https://doc.rust-lang.org/stable/std/net/struct.Ipv4Addr.html#method.is_link_local
4246[`Ipv4Addr::is_multicast`]: https://doc.rust-lang.org/stable/std/net/struct.Ipv4Addr.html#method.is_multicast
4247[`Ipv4Addr::is_broadcast`]: https://doc.rust-lang.org/stable/std/net/struct.Ipv4Addr.html#method.is_broadcast
4248[`Ipv4Addr::is_documentation`]: https://doc.rust-lang.org/stable/std/net/struct.Ipv4Addr.html#method.is_documentation
4249[`Ipv4Addr::to_ipv6_compatible`]: https://doc.rust-lang.org/stable/std/net/struct.Ipv4Addr.html#method.to_ipv6_compatible
4250[`Ipv4Addr::to_ipv6_mapped`]: https://doc.rust-lang.org/stable/std/net/struct.Ipv4Addr.html#method.to_ipv6_mapped
4251[`Ipv6Addr::segments`]: https://doc.rust-lang.org/stable/std/net/struct.Ipv6Addr.html#method.segments
4252[`Ipv6Addr::is_unspecified`]: https://doc.rust-lang.org/stable/std/net/struct.Ipv6Addr.html#method.is_unspecified
4253[`Ipv6Addr::is_loopback`]: https://doc.rust-lang.org/stable/std/net/struct.Ipv6Addr.html#method.is_loopback
4254[`Ipv6Addr::is_multicast`]: https://doc.rust-lang.org/stable/std/net/struct.Ipv6Addr.html#method.is_multicast
4255[`Ipv6Addr::to_ipv4`]: https://doc.rust-lang.org/stable/std/net/struct.Ipv6Addr.html#method.to_ipv4
4256[`Layout::align`]: https://doc.rust-lang.org/stable/std/alloc/struct.Layout.html#method.align
4257[`Layout::from_size_align`]: https://doc.rust-lang.org/stable/std/alloc/struct.Layout.html#method.from_size_align
4258[`Layout::size`]: https://doc.rust-lang.org/stable/std/alloc/struct.Layout.html#method.size
4259[`Ord::clamp`]: https://doc.rust-lang.org/stable/std/cmp/trait.Ord.html#method.clamp
4260[`RefCell::take`]: https://doc.rust-lang.org/stable/std/cell/struct.RefCell.html#method.take
4261[`UnsafeCell::get_mut`]: https://doc.rust-lang.org/stable/std/cell/struct.UnsafeCell.html#method.get_mut
4262[`bool::then`]: https://doc.rust-lang.org/stable/std/primitive.bool.html#method.then
4263[`btree_map::Entry::or_insert_with_key`]: https://doc.rust-lang.org/stable/std/collections/btree_map/enum.Entry.html#method.or_insert_with_key
4264[`f32::clamp`]: https://doc.rust-lang.org/stable/std/primitive.f32.html#method.clamp
4265[`f64::clamp`]: https://doc.rust-lang.org/stable/std/primitive.f64.html#method.clamp
4266[`hash_map::Entry::or_insert_with_key`]: https://doc.rust-lang.org/stable/std/collections/hash_map/enum.Entry.html#method.or_insert_with_key
4267[`slice::fill`]: https://doc.rust-lang.org/stable/std/primitive.slice.html#method.fill
4268
4269
4270Version 1.49.0 (2020-12-31)
4271============================
4272
4273Language
4274-----------------------
4275
4276- [Unions can now implement `Drop`, and you can now have a field in a union
4277 with `ManuallyDrop<T>`.][77547]
4278- [You can now cast uninhabited enums to integers.][76199]
4279- [You can now bind by reference and by move in patterns.][76119] This
4280 allows you to selectively borrow individual components of a type. E.g.
4281 ```rust
4282 #[derive(Debug)]
4283 struct Person {
4284 name: String,
4285 age: u8,
4286 }
4287
4288 let person = Person {
4289 name: String::from("Alice"),
4290 age: 20,
4291 };
4292
4293 // `name` is moved out of person, but `age` is referenced.
4294 let Person { name, ref age } = person;
4295 println!("{} {}", name, age);
4296 ```
4297
4298Compiler
4299-----------------------
4300
4301- [Added tier 1\* support for `aarch64-unknown-linux-gnu`.][78228]
4302- [Added tier 2 support for `aarch64-apple-darwin`.][75991]
4303- [Added tier 2 support for `aarch64-pc-windows-msvc`.][75914]
4304- [Added tier 3 support for `mipsel-unknown-none`.][78676]
4305- [Raised the minimum supported LLVM version to LLVM 9.][78848]
4306- [Output from threads spawned in tests is now captured.][78227]
4307- [Change os and vendor values to "none" and "unknown" for some targets][78951]
4308
4309\* Refer to Rust's [platform support page][platform-support-doc] for more
4310information on Rust's tiered platform support.
4311
4312Libraries
4313-----------------------
4314
4315- [`RangeInclusive` now checks for exhaustion when calling `contains` and indexing.][78109]
4316- [`ToString::to_string` now no longer shrinks the internal buffer in the default implementation.][77997]
4317
4318Stabilized APIs
4319---------------
4320
4321- [`slice::select_nth_unstable`]
4322- [`slice::select_nth_unstable_by`]
4323- [`slice::select_nth_unstable_by_key`]
4324
4325The following previously stable methods are now `const`.
4326
4327- [`Poll::is_ready`]
4328- [`Poll::is_pending`]
4329
4330Cargo
4331-----------------------
4332- [Building a crate with `cargo-package` should now be independently reproducible.][cargo/8864]
4333- [`cargo-tree` now marks proc-macro crates.][cargo/8765]
4334- [Added `CARGO_PRIMARY_PACKAGE` build-time environment variable.][cargo/8758] This
4335 variable will be set if the crate being built is one the user selected to build, either
4336 with `-p` or through defaults.
4337- [You can now use glob patterns when specifying packages & targets.][cargo/8752]
4338
4339
4340Compatibility Notes
4341-------------------
4342
4343- [Demoted `i686-unknown-freebsd` from host tier 2 to target tier 2 support.][78746]
4344- [Macros that end with a semi-colon are now treated as statements even if they expand to nothing.][78376]
4345- [Rustc will now check for the validity of some built-in attributes on enum variants.][77015]
4346 Previously such invalid or unused attributes could be ignored.
4347- Leading whitespace is stripped more uniformly in documentation comments, which may change behavior. You
4348 read [this post about the changes][rustdoc-ws-post] for more details.
4349- [Trait bounds are no longer inferred for associated types.][79904]
4350
4351Internal Only
4352-------------
4353These changes provide no direct user facing benefits, but represent significant
4354improvements to the internals and overall performance of rustc and
4355related tools.
4356
4357- [rustc's internal crates are now compiled using the `initial-exec` Thread
4358 Local Storage model.][78201]
4359- [Calculate visibilities once in resolve.][78077]
4360- [Added `system` to the `llvm-libunwind` bootstrap config option.][77703]
4361- [Added `--color` for configuring terminal color support to bootstrap.][79004]
4362
4363
4364[75991]: https://github.com/rust-lang/rust/pull/75991
4365[78951]: https://github.com/rust-lang/rust/pull/78951
4366[78848]: https://github.com/rust-lang/rust/pull/78848
4367[78746]: https://github.com/rust-lang/rust/pull/78746
4368[78376]: https://github.com/rust-lang/rust/pull/78376
4369[78228]: https://github.com/rust-lang/rust/pull/78228
4370[78227]: https://github.com/rust-lang/rust/pull/78227
4371[78201]: https://github.com/rust-lang/rust/pull/78201
4372[78109]: https://github.com/rust-lang/rust/pull/78109
4373[78077]: https://github.com/rust-lang/rust/pull/78077
4374[77997]: https://github.com/rust-lang/rust/pull/77997
4375[77703]: https://github.com/rust-lang/rust/pull/77703
4376[77547]: https://github.com/rust-lang/rust/pull/77547
4377[77015]: https://github.com/rust-lang/rust/pull/77015
4378[76199]: https://github.com/rust-lang/rust/pull/76199
4379[76119]: https://github.com/rust-lang/rust/pull/76119
4380[75914]: https://github.com/rust-lang/rust/pull/75914
4381[79004]: https://github.com/rust-lang/rust/pull/79004
4382[78676]: https://github.com/rust-lang/rust/pull/78676
4383[79904]: https://github.com/rust-lang/rust/issues/79904
4384[cargo/8864]: https://github.com/rust-lang/cargo/pull/8864
4385[cargo/8765]: https://github.com/rust-lang/cargo/pull/8765
4386[cargo/8758]: https://github.com/rust-lang/cargo/pull/8758
4387[cargo/8752]: https://github.com/rust-lang/cargo/pull/8752
4388[`slice::select_nth_unstable`]: https://doc.rust-lang.org/nightly/std/primitive.slice.html#method.select_nth_unstable
4389[`slice::select_nth_unstable_by`]: https://doc.rust-lang.org/nightly/std/primitive.slice.html#method.select_nth_unstable_by
4390[`slice::select_nth_unstable_by_key`]: https://doc.rust-lang.org/nightly/std/primitive.slice.html#method.select_nth_unstable_by_key
4391[`Poll::is_ready`]: https://doc.rust-lang.org/stable/std/task/enum.Poll.html#method.is_ready
4392[`Poll::is_pending`]: https://doc.rust-lang.org/stable/std/task/enum.Poll.html#method.is_pending
4393[rustdoc-ws-post]: https://blog.guillaume-gomez.fr/articles/2020-11-11+New+doc+comment+handling+in+rustdoc
4394
4395Version 1.48.0 (2020-11-19)
4396==========================
4397
4398Language
4399--------
4400
4401- [The `unsafe` keyword is now syntactically permitted on modules.][75857] This
4402 is still rejected *semantically*, but can now be parsed by procedural macros.
4403
4404Compiler
4405--------
4406- [Stabilised the `-C link-self-contained=<yes|no>` compiler flag.][76158] This tells
4407 `rustc` whether to link its own C runtime and libraries or to rely on a external
4408 linker to find them. (Supported only on `windows-gnu`, `linux-musl`, and `wasi` platforms.)
4409- [You can now use `-C target-feature=+crt-static` on `linux-gnu` targets.][77386]
4410 Note: If you're using cargo you must explicitly pass the `--target` flag.
4411- [Added tier 2\* support for `aarch64-unknown-linux-musl`.][76420]
4412
4413\* Refer to Rust's [platform support page][platform-support-doc] for more
4414information on Rust's tiered platform support.
4415
4416Libraries
4417---------
4418- [`io::Write` is now implemented for `&ChildStdin` `&Sink`, `&Stdout`,
4419 and `&Stderr`.][76275]
4420- [All arrays of any length now implement `TryFrom<Vec<T>>`.][76310]
4421- [The `matches!` macro now supports having a trailing comma.][74880]
4422- [`Vec<A>` now implements `PartialEq<[B]>` where `A: PartialEq<B>`.][74194]
4423- [The `RefCell::{replace, replace_with, clone}` methods now all use `#[track_caller]`.][77055]
4424
4425Stabilized APIs
4426---------------
4427- [`slice::as_ptr_range`]
4428- [`slice::as_mut_ptr_range`]
4429- [`VecDeque::make_contiguous`]
4430- [`future::pending`]
4431- [`future::ready`]
4432
4433The following previously stable methods are now `const fn`'s:
4434
4435- [`Option::is_some`]
4436- [`Option::is_none`]
4437- [`Option::as_ref`]
4438- [`Result::is_ok`]
4439- [`Result::is_err`]
4440- [`Result::as_ref`]
4441- [`Ordering::reverse`]
4442- [`Ordering::then`]
4443
4444Cargo
4445-----
4446
4447Rustdoc
4448-------
4449- [You can now link to items in `rustdoc` using the intra-doc link
4450 syntax.][74430] E.g. ``/// Uses [`std::future`]`` will automatically generate
4451 a link to `std::future`'s documentation. See ["Linking to items by
4452 name"][intradoc-links] for more information.
4453- [You can now specify `#[doc(alias = "<alias>")]` on items to add search aliases
4454 when searching through `rustdoc`'s UI.][75740]
4455
4456Compatibility Notes
4457-------------------
4458- [Promotion of references to `'static` lifetime inside `const fn` now follows the
4459 same rules as inside a `fn` body.][75502] In particular, `&foo()` will not be
4460 promoted to `'static` lifetime any more inside `const fn`s.
4461- [Associated type bindings on trait objects are now verified to meet the bounds
4462 declared on the trait when checking that they implement the trait.][27675]
4463- [When trait bounds on associated types or opaque types are ambiguous, the
4464 compiler no longer makes an arbitrary choice on which bound to use.][54121]
4465- [Fixed recursive nonterminals not being expanded in macros during
4466 pretty-print/reparse check.][77153] This may cause errors if your macro wasn't
4467 correctly handling recursive nonterminal tokens.
4468- [`&mut` references to non zero-sized types are no longer promoted.][75585]
4469- [`rustc` will now warn if you use attributes like `#[link_name]` or `#[cold]`
4470 in places where they have no effect.][73461]
4471- [Updated `_mm256_extract_epi8` and `_mm256_extract_epi16` signatures in
4472 `arch::{x86, x86_64}` to return `i32` to match the vendor signatures.][73166]
4473- [`mem::uninitialized` will now panic if any inner types inside a struct or enum
4474 disallow zero-initialization.][71274]
4475- [`#[target_feature]` will now error if used in a place where it has no effect.][78143]
4476- [Foreign exceptions are now caught by `catch_unwind` and will cause an abort.][70212]
4477 Note: This behaviour is not guaranteed and is still considered undefined behaviour,
4478 see the [`catch_unwind`] documentation for further information.
4479
4480
4481
4482Internal Only
4483-------------
4484These changes provide no direct user facing benefits, but represent significant
4485improvements to the internals and overall performance of rustc and
4486related tools.
4487
4488- [Building `rustc` from source now uses `ninja` by default over `make`.][74922]
4489 You can continue building with `make` by setting `ninja=false` in
4490 your `config.toml`.
4491- [cg_llvm: `fewer_names` in `uncached_llvm_type`][76030]
4492- [Made `ensure_sufficient_stack()` non-generic][76680]
4493
4494[78143]: https://github.com/rust-lang/rust/issues/78143
4495[76680]: https://github.com/rust-lang/rust/pull/76680/
4496[76030]: https://github.com/rust-lang/rust/pull/76030/
4497[70212]: https://github.com/rust-lang/rust/pull/70212/
4498[27675]: https://github.com/rust-lang/rust/issues/27675/
4499[54121]: https://github.com/rust-lang/rust/issues/54121/
4500[71274]: https://github.com/rust-lang/rust/pull/71274/
4501[77386]: https://github.com/rust-lang/rust/pull/77386/
4502[77153]: https://github.com/rust-lang/rust/pull/77153/
4503[77055]: https://github.com/rust-lang/rust/pull/77055/
4504[76275]: https://github.com/rust-lang/rust/pull/76275/
4505[76310]: https://github.com/rust-lang/rust/pull/76310/
4506[76420]: https://github.com/rust-lang/rust/pull/76420/
4507[76158]: https://github.com/rust-lang/rust/pull/76158/
4508[75857]: https://github.com/rust-lang/rust/pull/75857/
4509[75585]: https://github.com/rust-lang/rust/pull/75585/
4510[75740]: https://github.com/rust-lang/rust/pull/75740/
4511[75502]: https://github.com/rust-lang/rust/pull/75502/
4512[74880]: https://github.com/rust-lang/rust/pull/74880/
4513[74922]: https://github.com/rust-lang/rust/pull/74922/
4514[74430]: https://github.com/rust-lang/rust/pull/74430/
4515[74194]: https://github.com/rust-lang/rust/pull/74194/
4516[73461]: https://github.com/rust-lang/rust/pull/73461/
4517[73166]: https://github.com/rust-lang/rust/pull/73166/
4518[intradoc-links]: https://doc.rust-lang.org/rustdoc/linking-to-items-by-name.html
4519[`catch_unwind`]: https://doc.rust-lang.org/std/panic/fn.catch_unwind.html
4520[`Option::is_some`]: https://doc.rust-lang.org/std/option/enum.Option.html#method.is_some
4521[`Option::is_none`]: https://doc.rust-lang.org/std/option/enum.Option.html#method.is_none
4522[`Option::as_ref`]: https://doc.rust-lang.org/std/option/enum.Option.html#method.as_ref
4523[`Result::is_ok`]: https://doc.rust-lang.org/std/result/enum.Result.html#method.is_ok
4524[`Result::is_err`]: https://doc.rust-lang.org/std/result/enum.Result.html#method.is_err
4525[`Result::as_ref`]: https://doc.rust-lang.org/std/result/enum.Result.html#method.as_ref
4526[`Ordering::reverse`]: https://doc.rust-lang.org/std/cmp/enum.Ordering.html#method.reverse
4527[`Ordering::then`]: https://doc.rust-lang.org/std/cmp/enum.Ordering.html#method.then
4528[`slice::as_ptr_range`]: https://doc.rust-lang.org/std/primitive.slice.html#method.as_ptr_range
4529[`slice::as_mut_ptr_range`]: https://doc.rust-lang.org/std/primitive.slice.html#method.as_mut_ptr_range
4530[`VecDeque::make_contiguous`]: https://doc.rust-lang.org/std/collections/struct.VecDeque.html#method.make_contiguous
4531[`future::pending`]: https://doc.rust-lang.org/std/future/fn.pending.html
4532[`future::ready`]: https://doc.rust-lang.org/std/future/fn.ready.html
4533
4534
4535Version 1.47.0 (2020-10-08)
4536==========================
4537
4538Language
4539--------
4540- [Closures will now warn when not used.][74869]
4541
4542Compiler
4543--------
4544- [Stabilized the `-C control-flow-guard` codegen option][73893], which enables
4545 [Control Flow Guard][1.47.0-cfg] for Windows platforms, and is ignored on other
4546 platforms.
4547- [Upgraded to LLVM 11.][73526]
4548- [Added tier 3\* support for the `thumbv4t-none-eabi` target.][74419]
4549- [Upgrade the FreeBSD toolchain to version 11.4][75204]
4550- [`RUST_BACKTRACE`'s output is now more compact.][75048]
4551
4552\* Refer to Rust's [platform support page][platform-support-doc] for more
4553information on Rust's tiered platform support.
4554
4555Libraries
4556---------
4557- [`CStr` now implements `Index<RangeFrom<usize>>`.][74021]
4558- [Traits in `std`/`core` are now implemented for arrays of any length, not just
4559 those of length less than 33.][74060]
4560- [`ops::RangeFull` and `ops::Range` now implement Default.][73197]
4561- [`panic::Location` now implements `Copy`, `Clone`, `Eq`, `Hash`, `Ord`,
4562 `PartialEq`, and `PartialOrd`.][73583]
4563
4564Stabilized APIs
4565---------------
4566- [`Ident::new_raw`]
4567- [`Range::is_empty`]
4568- [`RangeInclusive::is_empty`]
4569- [`Result::as_deref`]
4570- [`Result::as_deref_mut`]
4571- [`Vec::leak`]
4572- [`pointer::offset_from`]
4573- [`f32::TAU`]
4574- [`f64::TAU`]
4575
4576The following previously stable APIs have now been made const.
4577
4578- [The `new` method for all `NonZero` integers.][73858]
4579- [The `checked_add`,`checked_sub`,`checked_mul`,`checked_neg`, `checked_shl`,
4580 `checked_shr`, `saturating_add`, `saturating_sub`, and `saturating_mul`
4581 methods for all integers.][73858]
4582- [The `checked_abs`, `saturating_abs`, `saturating_neg`, and `signum` for all
4583 signed integers.][73858]
4584- [The `is_ascii_alphabetic`, `is_ascii_uppercase`, `is_ascii_lowercase`,
4585 `is_ascii_alphanumeric`, `is_ascii_digit`, `is_ascii_hexdigit`,
4586 `is_ascii_punctuation`, `is_ascii_graphic`, `is_ascii_whitespace`, and
4587 `is_ascii_control` methods for `char` and `u8`.][73858]
4588
4589Cargo
4590-----
4591- [`build-dependencies` are now built with opt-level 0 by default.][cargo/8500]
4592 You can override this by setting the following in your `Cargo.toml`.
4593 ```toml
4594 [profile.release.build-override]
4595 opt-level = 3
4596 ```
4597- [`cargo-help` will now display man pages for commands rather just the
4598 `--help` text.][cargo/8456]
4599- [`cargo-metadata` now emits a `test` field indicating if a target has
4600 tests enabled.][cargo/8478]
4601- [`workspace.default-members` now respects `workspace.exclude`.][cargo/8485]
4602- [`cargo-publish` will now use an alternative registry by default if it's the
4603 only registry specified in `package.publish`.][cargo/8571]
4604
4605Misc
4606----
4607- [Added a help button beside Rustdoc's searchbar that explains rustdoc's
4608 type based search.][75366]
4609- [Added the Ayu theme to rustdoc.][71237]
4610
4611Compatibility Notes
4612-------------------
4613- [Bumped the minimum supported Emscripten version to 1.39.20.][75716]
4614- [Fixed a regression parsing `{} && false` in tail expressions.][74650]
4615- [Added changes to how proc-macros are expanded in `macro_rules!` that should
4616 help to preserve more span information.][73084] These changes may cause
4617 compilation errors if your macro was unhygenic or didn't correctly handle
4618 `Delimiter::None`.
4619- [Moved support for the CloudABI target to tier 3.][75568]
4620- [`linux-gnu` targets now require minimum kernel 2.6.32 and glibc 2.11.][74163]
4621- [Added the `rustc-docs` component.][75560] This allows you to install
4622 and read the documentation for the compiler internal APIs. (Currently only
4623 available for `x86_64-unknown-linux-gnu`.)
4624
4625Internal Only
4626--------
4627
4628- [Improved default settings for bootstrapping in `x.py`.][73964] You can read details about this change in the ["Changes to `x.py` defaults"](https://blog.rust-lang.org/inside-rust/2020/08/30/changes-to-x-py-defaults.html) post on the Inside Rust blog.
4629
4630[1.47.0-cfg]: https://docs.microsoft.com/en-us/windows/win32/secbp/control-flow-guard
4631[75048]: https://github.com/rust-lang/rust/pull/75048/
4632[74163]: https://github.com/rust-lang/rust/pull/74163/
4633[71237]: https://github.com/rust-lang/rust/pull/71237/
4634[74869]: https://github.com/rust-lang/rust/pull/74869/
4635[73858]: https://github.com/rust-lang/rust/pull/73858/
4636[75716]: https://github.com/rust-lang/rust/pull/75716/
4637[75560]: https://github.com/rust-lang/rust/pull/75560/
4638[75568]: https://github.com/rust-lang/rust/pull/75568/
4639[75366]: https://github.com/rust-lang/rust/pull/75366/
4640[75204]: https://github.com/rust-lang/rust/pull/75204/
4641[74650]: https://github.com/rust-lang/rust/pull/74650/
4642[74419]: https://github.com/rust-lang/rust/pull/74419/
4643[73964]: https://github.com/rust-lang/rust/pull/73964/
4644[74021]: https://github.com/rust-lang/rust/pull/74021/
4645[74060]: https://github.com/rust-lang/rust/pull/74060/
4646[73893]: https://github.com/rust-lang/rust/pull/73893/
4647[73526]: https://github.com/rust-lang/rust/pull/73526/
4648[73583]: https://github.com/rust-lang/rust/pull/73583/
4649[73084]: https://github.com/rust-lang/rust/pull/73084/
4650[73197]: https://github.com/rust-lang/rust/pull/73197/
4651[cargo/8456]: https://github.com/rust-lang/cargo/pull/8456/
4652[cargo/8478]: https://github.com/rust-lang/cargo/pull/8478/
4653[cargo/8485]: https://github.com/rust-lang/cargo/pull/8485/
4654[cargo/8500]: https://github.com/rust-lang/cargo/pull/8500/
4655[cargo/8571]: https://github.com/rust-lang/cargo/pull/8571/
4656[`Ident::new_raw`]: https://doc.rust-lang.org/nightly/proc_macro/struct.Ident.html#method.new_raw
4657[`Range::is_empty`]: https://doc.rust-lang.org/nightly/std/ops/struct.Range.html#method.is_empty
4658[`RangeInclusive::is_empty`]: https://doc.rust-lang.org/nightly/std/ops/struct.RangeInclusive.html#method.is_empty
4659[`Result::as_deref_mut`]: https://doc.rust-lang.org/nightly/std/result/enum.Result.html#method.as_deref_mut
4660[`Result::as_deref`]: https://doc.rust-lang.org/nightly/std/result/enum.Result.html#method.as_deref
4661[`Vec::leak`]: https://doc.rust-lang.org/nightly/std/vec/struct.Vec.html#method.leak
4662[`f32::TAU`]: https://doc.rust-lang.org/nightly/std/f32/consts/constant.TAU.html
4663[`f64::TAU`]: https://doc.rust-lang.org/nightly/std/f64/consts/constant.TAU.html
4664[`pointer::offset_from`]: https://doc.rust-lang.org/nightly/std/primitive.pointer.html#method.offset_from
4665
4666
4667Version 1.46.0 (2020-08-27)
4668==========================
4669
4670Language
4671--------
4672- [`if`, `match`, and `loop` expressions can now be used in const functions.][72437]
4673- [Additionally you are now also able to coerce and cast to slices (`&[T]`) in
4674 const functions.][73862]
4675- [The `#[track_caller]` attribute can now be added to functions to use the
4676 function's caller's location information for panic messages.][72445]
4677- [Recursively indexing into tuples no longer needs parentheses.][71322] E.g.
4678 `x.0.0` over `(x.0).0`.
4679- [`mem::transmute` can now be used in statics and constants.][72920] **Note**
4680 You currently can't use `mem::transmute` in constant functions.
4681
4682Compiler
4683--------
4684- [You can now use the `cdylib` target on Apple iOS and tvOS platforms.][73516]
4685- [Enabled static "Position Independent Executables" by default
4686 for `x86_64-unknown-linux-musl`.][70740]
4687
4688Libraries
4689---------
4690- [`mem::forget` is now a `const fn`.][73887]
4691- [`String` now implements `From<char>`.][73466]
4692- [The `leading_ones`, and `trailing_ones` methods have been stabilised for all
4693 integer types.][73032]
4694- [`vec::IntoIter<T>` now implements `AsRef<[T]>`.][72583]
4695- [All non-zero integer types (`NonZeroU8`) now implement `TryFrom` for their
4696 zero-able equivalent (e.g. `TryFrom<u8>`).][72717]
4697- [`&[T]` and `&mut [T]` now implement `PartialEq<Vec<T>>`.][71660]
4698- [`(String, u16)` now implements `ToSocketAddrs`.][73007]
4699- [`vec::Drain<'_, T>` now implements `AsRef<[T]>`.][72584]
4700
4701Stabilized APIs
4702---------------
4703- [`Option::zip`]
4704- [`vec::Drain::as_slice`]
4705
4706Cargo
4707-----
4708Added a number of new environment variables that are now available when
4709compiling your crate.
4710
4711- [`CARGO_BIN_NAME` and `CARGO_CRATE_NAME`][cargo/8270] Providing the name of
4712 the specific binary being compiled and the name of the crate.
4713- [`CARGO_PKG_LICENSE`][cargo/8325] The license from the manifest of the package.
4714- [`CARGO_PKG_LICENSE_FILE`][cargo/8387] The path to the license file.
4715
4716Compatibility Notes
4717-------------------
4718- [The target configuration option `abi_blacklist` has been renamed
4719 to `unsupported_abis`.][74150] The old name will still continue to work.
4720- [Rustc will now warn if you cast a C-like enum that implements `Drop`.][72331]
4721 This was previously accepted but will become a hard error in a future release.
4722- [Rustc will fail to compile if you have a struct with
4723 `#[repr(i128)]` or `#[repr(u128)]`.][74109] This representation is currently only
4724 allowed on `enum`s.
4725- [Tokens passed to `macro_rules!` are now always captured.][73293] This helps
4726 ensure that spans have the correct information, and may cause breakage if you
4727 were relying on receiving spans with dummy information.
4728- [The InnoSetup installer for Windows is no longer available.][72569] This was
4729 a legacy installer that was replaced by a MSI installer a few years ago but
4730 was still being built.
4731- [`{f32, f64}::asinh` now returns the correct values for negative numbers.][72486]
4732- [Rustc will no longer accept overlapping trait implementations that only
4733 differ in how the lifetime was bound.][72493]
4734- [Rustc now correctly relates the lifetime of an existential associated
4735 type.][71896] This fixes some edge cases where `rustc` would erroneously allow
4736 you to pass a shorter lifetime than expected.
4737- [Rustc now dynamically links to `libz` (also called `zlib`) on Linux.][74420]
4738 The library will need to be installed for `rustc` to work, even though we
4739 expect it to be already available on most systems.
4740- [Tests annotated with `#[should_panic]` are broken on ARMv7 while running
4741 under QEMU.][74820]
4742- [Pretty printing of some tokens in procedural macros changed.][75453] The
4743 exact output returned by rustc's pretty printing is an unstable
4744 implementation detail: we recommend any macro relying on it to switch to a
4745 more robust parsing system.
4746
4747[75453]: https://github.com/rust-lang/rust/issues/75453/
4748[74820]: https://github.com/rust-lang/rust/issues/74820/
4749[74420]: https://github.com/rust-lang/rust/issues/74420/
4750[74109]: https://github.com/rust-lang/rust/pull/74109/
4751[74150]: https://github.com/rust-lang/rust/pull/74150/
4752[73862]: https://github.com/rust-lang/rust/pull/73862/
4753[73887]: https://github.com/rust-lang/rust/pull/73887/
4754[73466]: https://github.com/rust-lang/rust/pull/73466/
4755[73516]: https://github.com/rust-lang/rust/pull/73516/
4756[73293]: https://github.com/rust-lang/rust/pull/73293/
4757[73007]: https://github.com/rust-lang/rust/pull/73007/
4758[73032]: https://github.com/rust-lang/rust/pull/73032/
4759[72920]: https://github.com/rust-lang/rust/pull/72920/
4760[72569]: https://github.com/rust-lang/rust/pull/72569/
4761[72583]: https://github.com/rust-lang/rust/pull/72583/
4762[72584]: https://github.com/rust-lang/rust/pull/72584/
4763[72717]: https://github.com/rust-lang/rust/pull/72717/
4764[72437]: https://github.com/rust-lang/rust/pull/72437/
4765[72445]: https://github.com/rust-lang/rust/pull/72445/
4766[72486]: https://github.com/rust-lang/rust/pull/72486/
4767[72493]: https://github.com/rust-lang/rust/pull/72493/
4768[72331]: https://github.com/rust-lang/rust/pull/72331/
4769[71896]: https://github.com/rust-lang/rust/pull/71896/
4770[71660]: https://github.com/rust-lang/rust/pull/71660/
4771[71322]: https://github.com/rust-lang/rust/pull/71322/
4772[70740]: https://github.com/rust-lang/rust/pull/70740/
4773[cargo/8270]: https://github.com/rust-lang/cargo/pull/8270/
4774[cargo/8325]: https://github.com/rust-lang/cargo/pull/8325/
4775[cargo/8387]: https://github.com/rust-lang/cargo/pull/8387/
4776[`Option::zip`]: https://doc.rust-lang.org/stable/std/option/enum.Option.html#method.zip
4777[`vec::Drain::as_slice`]: https://doc.rust-lang.org/stable/std/vec/struct.Drain.html#method.as_slice
4778
4779
4780Version 1.45.2 (2020-08-03)
4781==========================
4782
4783* [Fix bindings in tuple struct patterns][74954]
4784* [Fix track_caller integration with trait objects][74784]
4785
4786[74954]: https://github.com/rust-lang/rust/issues/74954
4787[74784]: https://github.com/rust-lang/rust/issues/74784
4788
4789
4790Version 1.45.1 (2020-07-30)
4791==========================
4792
4793* [Fix const propagation with references.][73613]
4794* [rustfmt accepts rustfmt_skip in cfg_attr again.][73078]
4795* [Avoid spurious implicit region bound.][74509]
4796* [Install clippy on x.py install][74457]
4797
4798[73613]: https://github.com/rust-lang/rust/pull/73613
4799[73078]: https://github.com/rust-lang/rust/issues/73078
4800[74509]: https://github.com/rust-lang/rust/pull/74509
4801[74457]: https://github.com/rust-lang/rust/pull/74457
4802
4803
4804Version 1.45.0 (2020-07-16)
4805==========================
4806
4807Language
4808--------
4809- [Out of range float to int conversions using `as` has been defined as a saturating
4810 conversion.][71269] This was previously undefined behaviour, but you can use the
4811 `{f64, f32}::to_int_unchecked` methods to continue using the current behaviour, which
4812 may be desirable in rare performance sensitive situations.
4813- [`mem::Discriminant<T>` now uses `T`'s discriminant type instead of always
4814 using `u64`.][70705]
4815- [Function like procedural macros can now be used in expression, pattern, and statement
4816 positions.][68717] This means you can now use a function-like procedural macro
4817 anywhere you can use a declarative (`macro_rules!`) macro.
4818
4819Compiler
4820--------
4821- [You can now override individual target features through the `target-feature`
4822 flag.][72094] E.g. `-C target-feature=+avx2 -C target-feature=+fma` is now
4823 equivalent to `-C target-feature=+avx2,+fma`.
4824- [Added the `force-unwind-tables` flag.][69984] This option allows
4825 rustc to always generate unwind tables regardless of panic strategy.
4826- [Added the `embed-bitcode` flag.][71716] This codegen flag allows rustc
4827 to include LLVM bitcode into generated `rlib`s (this is on by default).
4828- [Added the `tiny` value to the `code-model` codegen flag.][72397]
4829- [Added tier 3 support\* for the `mipsel-sony-psp` target.][72062]
4830- [Added tier 3 support for the `thumbv7a-uwp-windows-msvc` target.][72133]
4831- [Upgraded to LLVM 10.][67759]
4832
4833\* Refer to Rust's [platform support page][platform-support-doc] for more
4834information on Rust's tiered platform support.
4835
4836
4837Libraries
4838---------
4839- [`net::{SocketAddr, SocketAddrV4, SocketAddrV6}` now implements `PartialOrd`
4840 and `Ord`.][72239]
4841- [`proc_macro::TokenStream` now implements `Default`.][72234]
4842- [You can now use `char` with
4843 `ops::{Range, RangeFrom, RangeFull, RangeInclusive, RangeTo}` to iterate over
4844 a range of codepoints.][72413] E.g.
4845 you can now write the following;
4846 ```rust
4847 for ch in 'a'..='z' {
4848 print!("{}", ch);
4849 }
4850 println!();
4851 // Prints "abcdefghijklmnopqrstuvwxyz"
4852 ```
4853- [`OsString` now implements `FromStr`.][71662]
4854- [The `saturating_neg` method has been added to all signed integer primitive
4855 types, and the `saturating_abs` method has been added for all integer
4856 primitive types.][71886]
4857- [`Arc<T>`, `Rc<T>` now implement `From<Cow<'_, T>>`, and `Box` now
4858 implements `From<Cow>` when `T` is `[T: Copy]`, `str`, `CStr`, `OsStr`,
4859 or `Path`.][71447]
4860- [`Box<[T]>` now implements `From<[T; N]>`.][71095]
4861- [`BitOr` and `BitOrAssign` are implemented for all `NonZero`
4862 integer types.][69813]
4863- [The `fetch_min`, and `fetch_max` methods have been added to all atomic
4864 integer types.][72324]
4865- [The `fetch_update` method has been added to all atomic integer types.][71843]
4866
4867Stabilized APIs
4868---------------
4869- [`Arc::as_ptr`]
4870- [`BTreeMap::remove_entry`]
4871- [`Rc::as_ptr`]
4872- [`rc::Weak::as_ptr`]
4873- [`rc::Weak::from_raw`]
4874- [`rc::Weak::into_raw`]
4875- [`str::strip_prefix`]
4876- [`str::strip_suffix`]
4877- [`sync::Weak::as_ptr`]
4878- [`sync::Weak::from_raw`]
4879- [`sync::Weak::into_raw`]
4880- [`char::UNICODE_VERSION`]
4881- [`Span::resolved_at`]
4882- [`Span::located_at`]
4883- [`Span::mixed_site`]
4884- [`unix::process::CommandExt::arg0`]
4885
4886Cargo
4887-----
4888
4889- [Cargo uses the `embed-bitcode` flag to optimize disk usage and build
4890 time.][cargo/8066]
4891
4892Misc
4893----
4894- [Rustdoc now supports strikethrough text in Markdown.][71928] E.g.
4895 `~~outdated information~~` becomes "~~outdated information~~".
4896- [Added an emoji to Rustdoc's deprecated API message.][72014]
4897
4898Compatibility Notes
4899-------------------
4900- [Trying to self initialize a static value (that is creating a value using
4901 itself) is unsound and now causes a compile error.][71140]
4902- [`{f32, f64}::powi` now returns a slightly different value on Windows.][73420]
4903 This is due to changes in LLVM's intrinsics which `{f32, f64}::powi` uses.
4904- [Rustdoc's CLI's extra error exit codes have been removed.][71900] These were
4905 previously undocumented and not intended for public use. Rustdoc still provides
4906 a non-zero exit code on errors.
4907- [Rustc's `lto` flag is incompatible with the new `embed-bitcode=no`.][71848]
4908 This may cause issues if LTO is enabled through `RUSTFLAGS` or `cargo rustc`
4909 flags while cargo is adding `embed-bitcode` itself. The recommended way to
4910 control LTO is with Cargo profiles, either in `Cargo.toml` or `.cargo/config`,
4911 or by setting `CARGO_PROFILE_<name>_LTO` in the environment.
4912
4913Internals Only
4914--------------
4915- [Make clippy a git subtree instead of a git submodule][70655]
4916- [Unify the undo log of all snapshot types][69464]
4917
4918[71848]: https://github.com/rust-lang/rust/issues/71848/
4919[73420]: https://github.com/rust-lang/rust/issues/73420/
4920[72324]: https://github.com/rust-lang/rust/pull/72324/
4921[71843]: https://github.com/rust-lang/rust/pull/71843/
4922[71886]: https://github.com/rust-lang/rust/pull/71886/
4923[72234]: https://github.com/rust-lang/rust/pull/72234/
4924[72239]: https://github.com/rust-lang/rust/pull/72239/
4925[72397]: https://github.com/rust-lang/rust/pull/72397/
4926[72413]: https://github.com/rust-lang/rust/pull/72413/
4927[72014]: https://github.com/rust-lang/rust/pull/72014/
4928[72062]: https://github.com/rust-lang/rust/pull/72062/
4929[72094]: https://github.com/rust-lang/rust/pull/72094/
4930[72133]: https://github.com/rust-lang/rust/pull/72133/
4931[67759]: https://github.com/rust-lang/rust/pull/67759/
4932[71900]: https://github.com/rust-lang/rust/pull/71900/
4933[71928]: https://github.com/rust-lang/rust/pull/71928/
4934[71662]: https://github.com/rust-lang/rust/pull/71662/
4935[71716]: https://github.com/rust-lang/rust/pull/71716/
4936[71447]: https://github.com/rust-lang/rust/pull/71447/
4937[71269]: https://github.com/rust-lang/rust/pull/71269/
4938[71095]: https://github.com/rust-lang/rust/pull/71095/
4939[71140]: https://github.com/rust-lang/rust/pull/71140/
4940[70655]: https://github.com/rust-lang/rust/pull/70655/
4941[70705]: https://github.com/rust-lang/rust/pull/70705/
4942[69984]: https://github.com/rust-lang/rust/pull/69984/
4943[69813]: https://github.com/rust-lang/rust/pull/69813/
4944[69464]: https://github.com/rust-lang/rust/pull/69464/
4945[68717]: https://github.com/rust-lang/rust/pull/68717/
4946[cargo/8066]: https://github.com/rust-lang/cargo/pull/8066
4947[`Arc::as_ptr`]: https://doc.rust-lang.org/stable/std/sync/struct.Arc.html#method.as_ptr
4948[`BTreeMap::remove_entry`]: https://doc.rust-lang.org/stable/std/collections/struct.BTreeMap.html#method.remove_entry
4949[`Rc::as_ptr`]: https://doc.rust-lang.org/stable/std/rc/struct.Rc.html#method.as_ptr
4950[`rc::Weak::as_ptr`]: https://doc.rust-lang.org/stable/std/rc/struct.Weak.html#method.as_ptr
4951[`rc::Weak::from_raw`]: https://doc.rust-lang.org/stable/std/rc/struct.Weak.html#method.from_raw
4952[`rc::Weak::into_raw`]: https://doc.rust-lang.org/stable/std/rc/struct.Weak.html#method.into_raw
4953[`sync::Weak::as_ptr`]: https://doc.rust-lang.org/stable/std/sync/struct.Weak.html#method.as_ptr
4954[`sync::Weak::from_raw`]: https://doc.rust-lang.org/stable/std/sync/struct.Weak.html#method.from_raw
4955[`sync::Weak::into_raw`]: https://doc.rust-lang.org/stable/std/sync/struct.Weak.html#method.into_raw
4956[`str::strip_prefix`]: https://doc.rust-lang.org/stable/std/primitive.str.html#method.strip_prefix
4957[`str::strip_suffix`]: https://doc.rust-lang.org/stable/std/primitive.str.html#method.strip_suffix
4958[`char::UNICODE_VERSION`]: https://doc.rust-lang.org/stable/std/char/constant.UNICODE_VERSION.html
4959[`Span::resolved_at`]: https://doc.rust-lang.org/stable/proc_macro/struct.Span.html#method.resolved_at
4960[`Span::located_at`]: https://doc.rust-lang.org/stable/proc_macro/struct.Span.html#method.located_at
4961[`Span::mixed_site`]: https://doc.rust-lang.org/stable/proc_macro/struct.Span.html#method.mixed_site
4962[`unix::process::CommandExt::arg0`]: https://doc.rust-lang.org/std/os/unix/process/trait.CommandExt.html#tymethod.arg0
4963
4964
4965Version 1.44.1 (2020-06-18)
4966===========================
4967
4968* [rustfmt accepts rustfmt_skip in cfg_attr again.][73078]
4969* [Don't hash executable filenames on apple platforms, fixing backtraces.][cargo/8329]
4970* [Fix crashes when finding backtrace on macOS.][71397]
4971* [Clippy applies lint levels into different files.][clippy/5356]
4972
4973[71397]: https://github.com/rust-lang/rust/issues/71397
4974[73078]: https://github.com/rust-lang/rust/issues/73078
4975[cargo/8329]: https://github.com/rust-lang/cargo/pull/8329
4976[clippy/5356]: https://github.com/rust-lang/rust-clippy/issues/5356
4977
4978
4979Version 1.44.0 (2020-06-04)
4980==========================
4981
4982Language
4983--------
4984- [You can now use `async/.await` with `#[no_std]` enabled.][69033]
4985- [Added the `unused_braces` lint.][70081]
4986
4987**Syntax-only changes**
4988
4989- [Expansion-driven outline module parsing][69838]
4990```rust
4991#[cfg(FALSE)]
4992mod foo {
4993 mod bar {
4994 mod baz; // `foo/bar/baz.rs` doesn't exist, but no error!
4995 }
4996}
4997```
4998
4999These are still rejected semantically, so you will likely receive an error but
5000these changes can be seen and parsed by macros and conditional compilation.
5001
5002Compiler
5003--------
5004- [Rustc now respects the `-C codegen-units` flag in incremental mode.][70156]
5005 Additionally when in incremental mode rustc defaults to 256 codegen units.
5006- [Refactored `catch_unwind` to have zero-cost, unless unwinding is enabled and
5007 a panic is thrown.][67502]
5008- [Added tier 3\* support for the `aarch64-unknown-none` and
5009 `aarch64-unknown-none-softfloat` targets.][68334]
5010- [Added tier 3 support for `arm64-apple-tvos` and
5011 `x86_64-apple-tvos` targets.][68191]
5012
5013
5014Libraries
5015---------
5016- [Special cased `vec![]` to map directly to `Vec::new()`.][70632] This allows
5017 `vec![]` to be able to be used in `const` contexts.
5018- [`convert::Infallible` now implements `Hash`.][70281]
5019- [`OsString` now implements `DerefMut` and `IndexMut` returning
5020 a `&mut OsStr`.][70048]
5021- [Unicode 13 is now supported.][69929]
5022- [`String` now implements `From<&mut str>`.][69661]
5023- [`IoSlice` now implements `Copy`.][69403]
5024- [`Vec<T>` now implements `From<[T; N]>`.][68692] Where `N` is at most 32.
5025- [`proc_macro::LexError` now implements `fmt::Display` and `Error`.][68899]
5026- [`from_le_bytes`, `to_le_bytes`, `from_be_bytes`, `to_be_bytes`,
5027 `from_ne_bytes`, and `to_ne_bytes` methods are now `const` for all
5028 integer types.][69373]
5029
5030Stabilized APIs
5031---------------
5032- [`PathBuf::with_capacity`]
5033- [`PathBuf::capacity`]
5034- [`PathBuf::clear`]
5035- [`PathBuf::reserve`]
5036- [`PathBuf::reserve_exact`]
5037- [`PathBuf::shrink_to_fit`]
5038- [`f32::to_int_unchecked`]
5039- [`f64::to_int_unchecked`]
5040- [`Layout::align_to`]
5041- [`Layout::pad_to_align`]
5042- [`Layout::array`]
5043- [`Layout::extend`]
5044
5045Cargo
5046-----
5047- [Added the `cargo tree` command which will print a tree graph of
5048 your dependencies.][cargo/8062] E.g.
5049 ```
5050 mdbook v0.3.2 (/Users/src/rust/mdbook)
5051 ├── ammonia v3.0.0
5052 │ ├── html5ever v0.24.0
5053 │ │ ├── log v0.4.8
5054 │ │ │ └── cfg-if v0.1.9
5055 │ │ ├── mac v0.1.1
5056 │ │ └── markup5ever v0.9.0
5057 │ │ ├── log v0.4.8 (*)
5058 │ │ ├── phf v0.7.24
5059 │ │ │ └── phf_shared v0.7.24
5060 │ │ │ ├── siphasher v0.2.3
5061 │ │ │ └── unicase v1.4.2
5062 │ │ │ [build-dependencies]
5063 │ │ │ └── version_check v0.1.5
5064 ...
5065 ```
5066 You can also display dependencies on multiple versions of the same crate with
5067 `cargo tree -d` (short for `cargo tree --duplicates`).
5068
5069Misc
5070----
5071- [Rustdoc now allows you to specify `--crate-version` to have rustdoc include
5072 the version in the sidebar.][69494]
5073
5074Compatibility Notes
5075-------------------
5076- [Rustc now correctly generates static libraries on Windows GNU targets with
5077 the `.a` extension, rather than the previous `.lib`.][70937]
5078- [Removed the `-C no_integrated_as` flag from rustc.][70345]
5079- [The `file_name` property in JSON output of macro errors now points the actual
5080 source file rather than the previous format of `<NAME macros>`.][70969]
5081 **Note:** this may not point to a file that actually exists on the user's system.
5082- [The minimum required external LLVM version has been bumped to LLVM 8.][71147]
5083- [`mem::{zeroed, uninitialised}` will now panic when used with types that do
5084 not allow zero initialization such as `NonZeroU8`.][66059] This was
5085 previously a warning.
5086- [In 1.45.0 (the next release) converting a `f64` to `u32` using the `as`
5087 operator has been defined as a saturating operation.][71269] This was previously
5088 undefined behaviour, but you can use the `{f64, f32}::to_int_unchecked` methods to
5089 continue using the current behaviour, which may be desirable in rare performance
5090 sensitive situations.
5091
5092Internal Only
5093-------------
5094These changes provide no direct user facing benefits, but represent significant
5095improvements to the internals and overall performance of rustc and
5096related tools.
5097
5098- [dep_graph Avoid allocating a set on when the number reads are small.][69778]
5099- [Replace big JS dict with JSON parsing.][71250]
5100
5101[69373]: https://github.com/rust-lang/rust/pull/69373/
5102[66059]: https://github.com/rust-lang/rust/pull/66059/
5103[68191]: https://github.com/rust-lang/rust/pull/68191/
5104[68899]: https://github.com/rust-lang/rust/pull/68899/
5105[71147]: https://github.com/rust-lang/rust/pull/71147/
5106[71250]: https://github.com/rust-lang/rust/pull/71250/
5107[70937]: https://github.com/rust-lang/rust/pull/70937/
5108[70969]: https://github.com/rust-lang/rust/pull/70969/
5109[70632]: https://github.com/rust-lang/rust/pull/70632/
5110[70281]: https://github.com/rust-lang/rust/pull/70281/
5111[70345]: https://github.com/rust-lang/rust/pull/70345/
5112[70048]: https://github.com/rust-lang/rust/pull/70048/
5113[70081]: https://github.com/rust-lang/rust/pull/70081/
5114[70156]: https://github.com/rust-lang/rust/pull/70156/
5115[71269]: https://github.com/rust-lang/rust/pull/71269/
5116[69838]: https://github.com/rust-lang/rust/pull/69838/
5117[69929]: https://github.com/rust-lang/rust/pull/69929/
5118[69661]: https://github.com/rust-lang/rust/pull/69661/
5119[69778]: https://github.com/rust-lang/rust/pull/69778/
5120[69494]: https://github.com/rust-lang/rust/pull/69494/
5121[69403]: https://github.com/rust-lang/rust/pull/69403/
5122[69033]: https://github.com/rust-lang/rust/pull/69033/
5123[68692]: https://github.com/rust-lang/rust/pull/68692/
5124[68334]: https://github.com/rust-lang/rust/pull/68334/
5125[67502]: https://github.com/rust-lang/rust/pull/67502/
5126[cargo/8062]: https://github.com/rust-lang/cargo/pull/8062/
5127[`PathBuf::with_capacity`]: https://doc.rust-lang.org/std/path/struct.PathBuf.html#method.with_capacity
5128[`PathBuf::capacity`]: https://doc.rust-lang.org/std/path/struct.PathBuf.html#method.capacity
5129[`PathBuf::clear`]: https://doc.rust-lang.org/std/path/struct.PathBuf.html#method.clear
5130[`PathBuf::reserve`]: https://doc.rust-lang.org/std/path/struct.PathBuf.html#method.reserve
5131[`PathBuf::reserve_exact`]: https://doc.rust-lang.org/std/path/struct.PathBuf.html#method.reserve_exact
5132[`PathBuf::shrink_to_fit`]: https://doc.rust-lang.org/std/path/struct.PathBuf.html#method.shrink_to_fit
5133[`f32::to_int_unchecked`]: https://doc.rust-lang.org/std/primitive.f32.html#method.to_int_unchecked
5134[`f64::to_int_unchecked`]: https://doc.rust-lang.org/std/primitive.f64.html#method.to_int_unchecked
5135[`Layout::align_to`]: https://doc.rust-lang.org/std/alloc/struct.Layout.html#method.align_to
5136[`Layout::pad_to_align`]: https://doc.rust-lang.org/std/alloc/struct.Layout.html#method.pad_to_align
5137[`Layout::array`]: https://doc.rust-lang.org/std/alloc/struct.Layout.html#method.array
5138[`Layout::extend`]: https://doc.rust-lang.org/std/alloc/struct.Layout.html#method.extend
5139
5140
5141Version 1.43.1 (2020-05-07)
5142===========================
5143
5144* [Updated openssl-src to 1.1.1g for CVE-2020-1967.][71430]
5145* [Fixed the stabilization of AVX-512 features.][71473]
5146* [Fixed `cargo package --list` not working with unpublished dependencies.][cargo/8151]
5147
5148[71430]: https://github.com/rust-lang/rust/pull/71430
5149[71473]: https://github.com/rust-lang/rust/issues/71473
5150[cargo/8151]: https://github.com/rust-lang/cargo/issues/8151
5151
5152
5153Version 1.43.0 (2020-04-23)
5154==========================
5155
5156Language
5157--------
5158- [Fixed using binary operations with `&{number}` (e.g. `&1.0`) not having
5159 the type inferred correctly.][68129]
5160- [Attributes such as `#[cfg()]` can now be used on `if` expressions.][69201]
5161
5162**Syntax only changes**
5163- [Allow `type Foo: Ord` syntactically.][69361]
5164- [Fuse associated and extern items up to defaultness.][69194]
5165- [Syntactically allow `self` in all `fn` contexts.][68764]
5166- [Merge `fn` syntax + cleanup item parsing.][68728]
5167- [`item` macro fragments can be interpolated into `trait`s, `impl`s, and `extern` blocks.][69366]
5168 For example, you may now write:
5169 ```rust
5170 macro_rules! mac_trait {
5171 ($i:item) => {
5172 trait T { $i }
5173 }
5174 }
5175 mac_trait! {
5176 fn foo() {}
5177 }
5178 ```
5179
5180These are still rejected *semantically*, so you will likely receive an error but
5181these changes can be seen and parsed by macros and
5182conditional compilation.
5183
5184
5185Compiler
5186--------
5187- [You can now pass multiple lint flags to rustc to override the previous
5188 flags.][67885] For example; `rustc -D unused -A unused-variables` denies
5189 everything in the `unused` lint group except `unused-variables` which
5190 is explicitly allowed. However, passing `rustc -A unused-variables -D unused` denies
5191 everything in the `unused` lint group **including** `unused-variables` since
5192 the allow flag is specified before the deny flag (and therefore overridden).
5193- [rustc will now prefer your system MinGW libraries over its bundled libraries
5194 if they are available on `windows-gnu`.][67429]
5195- [rustc now buffers errors/warnings printed in JSON.][69227]
5196
5197Libraries
5198---------
5199- [`Arc<[T; N]>`, `Box<[T; N]>`, and `Rc<[T; N]>`, now implement
5200 `TryFrom<Arc<[T]>>`,`TryFrom<Box<[T]>>`, and `TryFrom<Rc<[T]>>`
5201 respectively.][69538] **Note** These conversions are only available when `N`
5202 is `0..=32`.
5203- [You can now use associated constants on floats and integers directly, rather
5204 than having to import the module.][68952] e.g. You can now write `u32::MAX` or
5205 `f32::NAN` with no imports.
5206- [`u8::is_ascii` is now `const`.][68984]
5207- [`String` now implements `AsMut<str>`.][68742]
5208- [Added the `primitive` module to `std` and `core`.][67637] This module
5209 reexports Rust's primitive types. This is mainly useful in macros
5210 where you want avoid these types being shadowed.
5211- [Relaxed some of the trait bounds on `HashMap` and `HashSet`.][67642]
5212- [`string::FromUtf8Error` now implements `Clone + Eq`.][68738]
5213
5214Stabilized APIs
5215---------------
5216- [`Once::is_completed`]
5217- [`f32::LOG10_2`]
5218- [`f32::LOG2_10`]
5219- [`f64::LOG10_2`]
5220- [`f64::LOG2_10`]
5221- [`iter::once_with`]
5222
5223Cargo
5224-----
5225- [You can now set config `[profile]`s in your `.cargo/config`, or through
5226 your environment.][cargo/7823]
5227- [Cargo will now set `CARGO_BIN_EXE_<name>` pointing to a binary's
5228 executable path when running integration tests or benchmarks.][cargo/7697]
5229 `<name>` is the name of your binary as-is e.g. If you wanted the executable
5230 path for a binary named `my-program`you would use `env!("CARGO_BIN_EXE_my-program")`.
5231
5232Misc
5233----
5234- [Certain checks in the `const_err` lint were deemed unrelated to const
5235 evaluation][69185], and have been moved to the `unconditional_panic` and
5236 `arithmetic_overflow` lints.
5237
5238Compatibility Notes
5239-------------------
5240
5241- [Having trailing syntax in the `assert!` macro is now a hard error.][69548] This
5242 has been a warning since 1.36.0.
5243- [Fixed `Self` not having the correctly inferred type.][69340] This incorrectly
5244 led to some instances being accepted, and now correctly emits a hard error.
5245
5246[69340]: https://github.com/rust-lang/rust/pull/69340
5247
5248Internal Only
5249-------------
5250These changes provide no direct user facing benefits, but represent significant
5251improvements to the internals and overall performance of `rustc` and
5252related tools.
5253
5254- [All components are now built with `opt-level=3` instead of `2`.][67878]
5255- [Improved how rustc generates drop code.][67332]
5256- [Improved performance from `#[inline]`-ing certain hot functions.][69256]
5257- [traits: preallocate 2 Vecs of known initial size][69022]
5258- [Avoid exponential behaviour when relating types][68772]
5259- [Skip `Drop` terminators for enum variants without drop glue][68943]
5260- [Improve performance of coherence checks][68966]
5261- [Deduplicate types in the generator witness][68672]
5262- [Invert control in struct_lint_level.][68725]
5263
5264[67332]: https://github.com/rust-lang/rust/pull/67332/
5265[67429]: https://github.com/rust-lang/rust/pull/67429/
5266[67637]: https://github.com/rust-lang/rust/pull/67637/
5267[67642]: https://github.com/rust-lang/rust/pull/67642/
5268[67878]: https://github.com/rust-lang/rust/pull/67878/
5269[67885]: https://github.com/rust-lang/rust/pull/67885/
5270[68129]: https://github.com/rust-lang/rust/pull/68129/
5271[68672]: https://github.com/rust-lang/rust/pull/68672/
5272[68725]: https://github.com/rust-lang/rust/pull/68725/
5273[68728]: https://github.com/rust-lang/rust/pull/68728/
5274[68738]: https://github.com/rust-lang/rust/pull/68738/
5275[68742]: https://github.com/rust-lang/rust/pull/68742/
5276[68764]: https://github.com/rust-lang/rust/pull/68764/
5277[68772]: https://github.com/rust-lang/rust/pull/68772/
5278[68943]: https://github.com/rust-lang/rust/pull/68943/
5279[68952]: https://github.com/rust-lang/rust/pull/68952/
5280[68966]: https://github.com/rust-lang/rust/pull/68966/
5281[68984]: https://github.com/rust-lang/rust/pull/68984/
5282[69022]: https://github.com/rust-lang/rust/pull/69022/
5283[69185]: https://github.com/rust-lang/rust/pull/69185/
5284[69194]: https://github.com/rust-lang/rust/pull/69194/
5285[69201]: https://github.com/rust-lang/rust/pull/69201/
5286[69227]: https://github.com/rust-lang/rust/pull/69227/
5287[69548]: https://github.com/rust-lang/rust/pull/69548/
5288[69256]: https://github.com/rust-lang/rust/pull/69256/
5289[69361]: https://github.com/rust-lang/rust/pull/69361/
5290[69366]: https://github.com/rust-lang/rust/pull/69366/
5291[69538]: https://github.com/rust-lang/rust/pull/69538/
5292[cargo/7823]: https://github.com/rust-lang/cargo/pull/7823
5293[cargo/7697]: https://github.com/rust-lang/cargo/pull/7697
5294[`Once::is_completed`]: https://doc.rust-lang.org/std/sync/struct.Once.html#method.is_completed
5295[`f32::LOG10_2`]: https://doc.rust-lang.org/std/f32/consts/constant.LOG10_2.html
5296[`f32::LOG2_10`]: https://doc.rust-lang.org/std/f32/consts/constant.LOG2_10.html
5297[`f64::LOG10_2`]: https://doc.rust-lang.org/std/f64/consts/constant.LOG10_2.html
5298[`f64::LOG2_10`]: https://doc.rust-lang.org/std/f64/consts/constant.LOG2_10.html
5299[`iter::once_with`]: https://doc.rust-lang.org/std/iter/fn.once_with.html
5300
5301
5302Version 1.42.0 (2020-03-12)
5303==========================
5304
5305Language
5306--------
5307- [You can now use the slice pattern syntax with subslices.][67712] e.g.
5308 ```rust
5309 fn foo(words: &[&str]) {
5310 match words {
5311 ["Hello", "World", "!", ..] => println!("Hello World!"),
5312 ["Foo", "Bar", ..] => println!("Baz"),
5313 rest => println!("{:?}", rest),
5314 }
5315 }
5316 ```
5317- [You can now use `#[repr(transparent)]` on univariant `enum`s.][68122] Meaning
5318 that you can create an enum that has the exact layout and ABI of the type
5319 it contains.
5320- [You can now use outer attribute procedural macros on inline modules.][64273]
5321- [There are some *syntax-only* changes:][67131]
5322 - `default` is syntactically allowed before items in `trait` definitions.
5323 - Items in `impl`s (i.e. `const`s, `type`s, and `fn`s) may syntactically
5324 leave out their bodies in favor of `;`.
5325 - Bounds on associated types in `impl`s are now syntactically allowed
5326 (e.g. `type Foo: Ord;`).
5327 - `...` (the C-variadic type) may occur syntactically directly as the type of
5328 any function parameter.
5329
5330 These are still rejected *semantically*, so you will likely receive an error
5331 but these changes can be seen and parsed by procedural macros and
5332 conditional compilation.
5333
5334Compiler
5335--------
5336- [Added tier 2\* support for `armv7a-none-eabi`.][68253]
5337- [Added tier 2 support for `riscv64gc-unknown-linux-gnu`.][68339]
5338- [`Option::{expect,unwrap}` and
5339 `Result::{expect, expect_err, unwrap, unwrap_err}` now produce panic messages
5340 pointing to the location where they were called, rather than
5341 `core`'s internals. ][67887]
5342
5343\* Refer to Rust's [platform support page][platform-support-doc] for more
5344information on Rust's tiered platform support.
5345
5346Libraries
5347---------
5348- [`iter::Empty<T>` now implements `Send` and `Sync` for any `T`.][68348]
5349- [`Pin::{map_unchecked, map_unchecked_mut}` no longer require the return type
5350 to implement `Sized`.][67935]
5351- [`io::Cursor` now derives `PartialEq` and `Eq`.][67233]
5352- [`Layout::new` is now `const`.][66254]
5353- [Added Standard Library support for `riscv64gc-unknown-linux-gnu`.][66899]
5354
5355
5356Stabilized APIs
5357---------------
5358- [`CondVar::wait_while`]
5359- [`CondVar::wait_timeout_while`]
5360- [`DebugMap::key`]
5361- [`DebugMap::value`]
5362- [`ManuallyDrop::take`]
5363- [`matches!`]
5364- [`ptr::slice_from_raw_parts_mut`]
5365- [`ptr::slice_from_raw_parts`]
5366
5367Cargo
5368-----
5369- [You no longer need to include `extern crate proc_macro;` to be able to
5370 `use proc_macro;` in the `2018` edition.][cargo/7700]
5371
5372Compatibility Notes
5373-------------------
5374- [`Error::description` has been deprecated, and its use will now produce a
5375 warning.][66919] It's recommended to use `Display`/`to_string` instead.
5376
5377[68253]: https://github.com/rust-lang/rust/pull/68253/
5378[68348]: https://github.com/rust-lang/rust/pull/68348/
5379[67935]: https://github.com/rust-lang/rust/pull/67935/
5380[68339]: https://github.com/rust-lang/rust/pull/68339/
5381[68122]: https://github.com/rust-lang/rust/pull/68122/
5382[64273]: https://github.com/rust-lang/rust/pull/64273/
5383[67712]: https://github.com/rust-lang/rust/pull/67712/
5384[67887]: https://github.com/rust-lang/rust/pull/67887/
5385[67131]: https://github.com/rust-lang/rust/pull/67131/
5386[67233]: https://github.com/rust-lang/rust/pull/67233/
5387[66899]: https://github.com/rust-lang/rust/pull/66899/
5388[66919]: https://github.com/rust-lang/rust/pull/66919/
5389[66254]: https://github.com/rust-lang/rust/pull/66254/
5390[cargo/7700]: https://github.com/rust-lang/cargo/pull/7700
5391[`DebugMap::key`]: https://doc.rust-lang.org/stable/std/fmt/struct.DebugMap.html#method.key
5392[`DebugMap::value`]: https://doc.rust-lang.org/stable/std/fmt/struct.DebugMap.html#method.value
5393[`ManuallyDrop::take`]: https://doc.rust-lang.org/stable/std/mem/struct.ManuallyDrop.html#method.take
5394[`matches!`]: https://doc.rust-lang.org/stable/std/macro.matches.html
5395[`ptr::slice_from_raw_parts_mut`]: https://doc.rust-lang.org/stable/std/ptr/fn.slice_from_raw_parts_mut.html
5396[`ptr::slice_from_raw_parts`]: https://doc.rust-lang.org/stable/std/ptr/fn.slice_from_raw_parts.html
5397[`CondVar::wait_while`]: https://doc.rust-lang.org/stable/std/sync/struct.Condvar.html#method.wait_while
5398[`CondVar::wait_timeout_while`]: https://doc.rust-lang.org/stable/std/sync/struct.Condvar.html#method.wait_timeout_while
5399
5400
5401Version 1.41.1 (2020-02-27)
5402===========================
5403
5404* [Always check types of static items][69145]
5405* [Always check lifetime bounds of `Copy` impls][69145]
5406* [Fix miscompilation in callers of `Layout::repeat`][69225]
5407* [Rust 1.41.0 was announced as the last Rust release with tier 1 or tier 2 support for 32-bit Apple targets][apple-32bit-drop].
5408 That announcement did not expect a patch release. 1.41.1 also includes release binaries for these targets.
5409
5410[69225]: https://github.com/rust-lang/rust/issues/69225
5411[69145]: https://github.com/rust-lang/rust/pull/69145
5412
5413
5414Version 1.41.0 (2020-01-30)
5415===========================
5416
5417Language
5418--------
5419
5420- [You can now pass type parameters to foreign items when implementing
5421 traits.][65879] E.g. You can now write `impl<T> From<Foo> for Vec<T> {}`.
5422- [You can now arbitrarily nest receiver types in the `self` position.][64325] E.g. you can
5423 now write `fn foo(self: Box<Box<Self>>) {}`. Previously only `Self`, `&Self`,
5424 `&mut Self`, `Arc<Self>`, `Rc<Self>`, and `Box<Self>` were allowed.
5425- [You can now use any valid identifier in a `format_args` macro.][66847]
5426 Previously identifiers starting with an underscore were not allowed.
5427- [Visibility modifiers (e.g. `pub`) are now syntactically allowed on trait items and
5428 enum variants.][66183] These are still rejected semantically, but
5429 can be seen and parsed by procedural macros and conditional compilation.
5430- [You can now define a Rust `extern "C"` function with `Box<T>` and use `T*` as the corresponding
5431 type on the C side.][62514] Please see [the documentation][box-memory-layout] for more information,
5432 including the important caveat about preferring to avoid `Box<T>` in Rust signatures for functions defined in C.
5433
5434[box-memory-layout]: https://doc.rust-lang.org/std/boxed/index.html#memory-layout
5435
5436Compiler
5437--------
5438
5439- [Rustc will now warn if you have unused loop `'label`s.][66325]
5440- [Removed support for the `i686-unknown-dragonfly` target.][67255]
5441- [Added tier 3 support\* for the `riscv64gc-unknown-linux-gnu` target.][66661]
5442- [You can now pass an arguments file passing the `@path` syntax
5443 to rustc.][66172] Note that the format differs somewhat from what is
5444 found in other tooling; please see [the documentation][argfile-docs] for
5445 more information.
5446- [You can now provide `--extern` flag without a path, indicating that it is
5447 available from the search path or specified with an `-L` flag.][64882]
5448
5449\* Refer to Rust's [platform support page][platform-support-doc] for more
5450information on Rust's tiered platform support.
5451
5452[argfile-docs]: https://doc.rust-lang.org/nightly/rustc/command-line-arguments.html#path-load-command-line-flags-from-a-path
5453
5454Libraries
5455---------
5456
5457- [The `core::panic` module is now stable.][66771] It was already stable
5458 through `std`.
5459- [`NonZero*` numerics now implement `From<NonZero*>` if it's a smaller integer
5460 width.][66277] E.g. `NonZeroU16` now implements `From<NonZeroU8>`.
5461- [`MaybeUninit<T>` now implements `fmt::Debug`.][65013]
5462
5463Stabilized APIs
5464---------------
5465
5466- [`Result::map_or`]
5467- [`Result::map_or_else`]
5468- [`std::rc::Weak::weak_count`]
5469- [`std::rc::Weak::strong_count`]
5470- [`std::sync::Weak::weak_count`]
5471- [`std::sync::Weak::strong_count`]
5472
5473Cargo
5474-----
5475
5476- [Cargo will now document all the private items for binary crates
5477 by default.][cargo/7593]
5478- [`cargo-install` will now reinstall the package if it detects that it is out
5479 of date.][cargo/7560]
5480- [Cargo.lock now uses a more git friendly format that should help to reduce
5481 merge conflicts.][cargo/7579]
5482- [You can now override specific dependencies's build settings][cargo/7591] E.g.
5483 `[profile.dev.package.image] opt-level = 2` sets the `image` crate's
5484 optimisation level to `2` for debug builds. You can also use
5485 `[profile.<profile>.build-override]` to override build scripts and
5486 their dependencies.
5487
5488Misc
5489----
5490
5491- [You can now specify `edition` in documentation code blocks to compile the block
5492 for that edition.][66238] E.g. `edition2018` tells rustdoc that the code sample
5493 should be compiled the 2018 edition of Rust.
5494- [You can now provide custom themes to rustdoc with `--theme`, and check the
5495 current theme with `--check-theme`.][54733]
5496- [You can use `#[cfg(doc)]` to compile an item when building documentation.][61351]
5497
5498Compatibility Notes
5499-------------------
5500
5501- [As previously announced 1.41 will be the last tier 1 release for 32-bit
5502 Apple targets.][apple-32bit-drop] This means that the source code is still
5503 available to build, but the targets are no longer being tested and release
5504 binaries for those platforms will no longer be distributed by the Rust project.
5505 Please refer to the linked blog post for more information.
5506
5507[54733]: https://github.com/rust-lang/rust/pull/54733/
5508[61351]: https://github.com/rust-lang/rust/pull/61351/
5509[62514]: https://github.com/rust-lang/rust/pull/62514/
5510[67255]: https://github.com/rust-lang/rust/pull/67255/
5511[66661]: https://github.com/rust-lang/rust/pull/66661/
5512[66771]: https://github.com/rust-lang/rust/pull/66771/
5513[66847]: https://github.com/rust-lang/rust/pull/66847/
5514[66238]: https://github.com/rust-lang/rust/pull/66238/
5515[66277]: https://github.com/rust-lang/rust/pull/66277/
5516[66325]: https://github.com/rust-lang/rust/pull/66325/
5517[66172]: https://github.com/rust-lang/rust/pull/66172/
5518[66183]: https://github.com/rust-lang/rust/pull/66183/
5519[65879]: https://github.com/rust-lang/rust/pull/65879/
5520[65013]: https://github.com/rust-lang/rust/pull/65013/
5521[64882]: https://github.com/rust-lang/rust/pull/64882/
5522[64325]: https://github.com/rust-lang/rust/pull/64325/
5523[cargo/7560]: https://github.com/rust-lang/cargo/pull/7560/
5524[cargo/7579]: https://github.com/rust-lang/cargo/pull/7579/
5525[cargo/7591]: https://github.com/rust-lang/cargo/pull/7591/
5526[cargo/7593]: https://github.com/rust-lang/cargo/pull/7593/
5527[`Result::map_or_else`]: https://doc.rust-lang.org/std/result/enum.Result.html#method.map_or_else
5528[`Result::map_or`]: https://doc.rust-lang.org/std/result/enum.Result.html#method.map_or
5529[`std::rc::Weak::weak_count`]: https://doc.rust-lang.org/std/rc/struct.Weak.html#method.weak_count
5530[`std::rc::Weak::strong_count`]: https://doc.rust-lang.org/std/rc/struct.Weak.html#method.strong_count
5531[`std::sync::Weak::weak_count`]: https://doc.rust-lang.org/std/sync/struct.Weak.html#method.weak_count
5532[`std::sync::Weak::strong_count`]: https://doc.rust-lang.org/std/sync/struct.Weak.html#method.strong_count
5533[apple-32bit-drop]: https://blog.rust-lang.org/2020/01/03/reducing-support-for-32-bit-apple-targets.html
5534
5535Version 1.40.0 (2019-12-19)
5536===========================
5537
5538Language
5539--------
5540- [You can now use tuple `struct`s and tuple `enum` variant's constructors in
5541 `const` contexts.][65188] e.g.
5542
5543 ```rust
5544 pub struct Point(i32, i32);
5545
5546 const ORIGIN: Point = {
5547 let constructor = Point;
5548
5549 constructor(0, 0)
5550 };
5551 ```
5552
5553- [You can now mark `struct`s, `enum`s, and `enum` variants with the `#[non_exhaustive]` attribute to
5554 indicate that there may be variants or fields added in the future.][64639]
5555 For example this requires adding a wild-card branch (`_ => {}`) to any match
5556 statements on a non-exhaustive `enum`. [(RFC 2008)]
5557- [You can now use function-like procedural macros in `extern` blocks and in
5558 type positions.][63931] e.g. `type Generated = macro!();`
5559- [Function-like and attribute procedural macros can now emit
5560 `macro_rules!` items, so you can now have your macros generate macros.][64035]
5561- [The `meta` pattern matcher in `macro_rules!` now correctly matches the modern
5562 attribute syntax.][63674] For example `(#[$m:meta])` now matches `#[attr]`,
5563 `#[attr{tokens}]`, `#[attr[tokens]]`, and `#[attr(tokens)]`.
5564
5565Compiler
5566--------
5567- [Added tier 3 support\* for the
5568 `thumbv7neon-unknown-linux-musleabihf` target.][66103]
5569- [Added tier 3 support for the
5570 `aarch64-unknown-none-softfloat` target.][64589]
5571- [Added tier 3 support for the `mips64-unknown-linux-muslabi64`, and
5572 `mips64el-unknown-linux-muslabi64` targets.][65843]
5573
5574\* Refer to Rust's [platform support page][platform-support-doc] for more
5575 information on Rust's tiered platform support.
5576
5577Libraries
5578---------
5579- [The `is_power_of_two` method on unsigned numeric types is now a `const` function.][65092]
5580
5581Stabilized APIs
5582---------------
5583- [`BTreeMap::get_key_value`]
5584- [`HashMap::get_key_value`]
5585- [`Option::as_deref_mut`]
5586- [`Option::as_deref`]
5587- [`Option::flatten`]
5588- [`UdpSocket::peer_addr`]
5589- [`f32::to_be_bytes`]
5590- [`f32::to_le_bytes`]
5591- [`f32::to_ne_bytes`]
5592- [`f64::to_be_bytes`]
5593- [`f64::to_le_bytes`]
5594- [`f64::to_ne_bytes`]
5595- [`f32::from_be_bytes`]
5596- [`f32::from_le_bytes`]
5597- [`f32::from_ne_bytes`]
5598- [`f64::from_be_bytes`]
5599- [`f64::from_le_bytes`]
5600- [`f64::from_ne_bytes`]
5601- [`mem::take`]
5602- [`slice::repeat`]
5603- [`todo!`]
5604
5605Cargo
5606-----
5607- [Cargo will now always display warnings, rather than only on
5608 fresh builds.][cargo/7450]
5609- [Feature flags (except `--all-features`) passed to a virtual workspace will
5610 now produce an error.][cargo/7507] Previously these flags were ignored.
5611- [You can now publish `dev-dependencies` without including
5612 a `version`.][cargo/7333]
5613
5614Misc
5615----
5616- [You can now specify the `#[cfg(doctest)]` attribute to include an item only
5617 when running documentation tests with `rustdoc`.][63803]
5618
5619Compatibility Notes
5620-------------------
5621- [As previously announced, any previous NLL warnings in the 2015 edition are
5622 now hard errors.][64221]
5623- [The `include!` macro will now warn if it failed to include the
5624 entire file.][64284] The `include!` macro unintentionally only includes the
5625 first _expression_ in a file, and this can be unintuitive. This will become
5626 either a hard error in a future release, or the behavior may be fixed to include all expressions as expected.
5627- [Using `#[inline]` on function prototypes and consts now emits a warning under
5628 `unused_attribute` lint.][65294] Using `#[inline]` anywhere else inside traits
5629 or `extern` blocks now correctly emits a hard error.
5630
5631[65294]: https://github.com/rust-lang/rust/pull/65294/
5632[66103]: https://github.com/rust-lang/rust/pull/66103/
5633[65843]: https://github.com/rust-lang/rust/pull/65843/
5634[65188]: https://github.com/rust-lang/rust/pull/65188/
5635[65092]: https://github.com/rust-lang/rust/pull/65092/
5636[64589]: https://github.com/rust-lang/rust/pull/64589/
5637[64639]: https://github.com/rust-lang/rust/pull/64639/
5638[64221]: https://github.com/rust-lang/rust/pull/64221/
5639[64284]: https://github.com/rust-lang/rust/pull/64284/
5640[63931]: https://github.com/rust-lang/rust/pull/63931/
5641[64035]: https://github.com/rust-lang/rust/pull/64035/
5642[63674]: https://github.com/rust-lang/rust/pull/63674/
5643[63803]: https://github.com/rust-lang/rust/pull/63803/
5644[cargo/7450]: https://github.com/rust-lang/cargo/pull/7450/
5645[cargo/7507]: https://github.com/rust-lang/cargo/pull/7507/
5646[cargo/7333]: https://github.com/rust-lang/cargo/pull/7333/
5647[(rfc 2008)]: https://rust-lang.github.io/rfcs/2008-non-exhaustive.html
5648[`f32::to_be_bytes`]: https://doc.rust-lang.org/std/primitive.f32.html#method.to_be_bytes
5649[`f32::to_le_bytes`]: https://doc.rust-lang.org/std/primitive.f32.html#method.to_le_bytes
5650[`f32::to_ne_bytes`]: https://doc.rust-lang.org/std/primitive.f32.html#method.to_ne_bytes
5651[`f64::to_be_bytes`]: https://doc.rust-lang.org/std/primitive.f64.html#method.to_be_bytes
5652[`f64::to_le_bytes`]: https://doc.rust-lang.org/std/primitive.f64.html#method.to_le_bytes
5653[`f64::to_ne_bytes`]: https://doc.rust-lang.org/std/primitive.f64.html#method.to_ne_bytes
5654[`f32::from_be_bytes`]: https://doc.rust-lang.org/std/primitive.f32.html#method.from_be_bytes
5655[`f32::from_le_bytes`]: https://doc.rust-lang.org/std/primitive.f32.html#method.from_le_bytes
5656[`f32::from_ne_bytes`]: https://doc.rust-lang.org/std/primitive.f32.html#method.from_ne_bytes
5657[`f64::from_be_bytes`]: https://doc.rust-lang.org/std/primitive.f64.html#method.from_be_bytes
5658[`f64::from_le_bytes`]: https://doc.rust-lang.org/std/primitive.f64.html#method.from_le_bytes
5659[`f64::from_ne_bytes`]: https://doc.rust-lang.org/std/primitive.f64.html#method.from_ne_bytes
5660[`option::flatten`]: https://doc.rust-lang.org/std/option/enum.Option.html#method.flatten
5661[`option::as_deref`]: https://doc.rust-lang.org/std/option/enum.Option.html#method.as_deref
5662[`option::as_deref_mut`]: https://doc.rust-lang.org/std/option/enum.Option.html#method.as_deref_mut
5663[`hashmap::get_key_value`]: https://doc.rust-lang.org/std/collections/struct.HashMap.html#method.get_key_value
5664[`btreemap::get_key_value`]: https://doc.rust-lang.org/std/collections/struct.BTreeMap.html#method.get_key_value
5665[`slice::repeat`]: https://doc.rust-lang.org/std/primitive.slice.html#method.repeat
5666[`mem::take`]: https://doc.rust-lang.org/std/mem/fn.take.html
5667[`udpsocket::peer_addr`]: https://doc.rust-lang.org/std/net/struct.UdpSocket.html#method.peer_addr
5668[`todo!`]: https://doc.rust-lang.org/std/macro.todo.html
5669
5670
5671Version 1.39.0 (2019-11-07)
5672===========================
5673
5674Language
5675--------
5676- [You can now create `async` functions and blocks with `async fn`, `async move {}`, and
5677 `async {}` respectively, and you can now call `.await` on async expressions.][63209]
5678- [You can now use certain attributes on function, closure, and function pointer
5679 parameters.][64010] These attributes include `cfg`, `cfg_attr`, `allow`, `warn`,
5680 `deny`, `forbid` as well as inert helper attributes used by procedural macro
5681 attributes applied to items. e.g.
5682 ```rust
5683 fn len(
5684 #[cfg(windows)] slice: &[u16],
5685 #[cfg(not(windows))] slice: &[u8],
5686 ) -> usize {
5687 slice.len()
5688 }
5689 ```
5690- [You can now take shared references to bind-by-move patterns in the `if` guards
5691 of `match` arms.][63118] e.g.
5692 ```rust
5693 fn main() {
5694 let array: Box<[u8; 4]> = Box::new([1, 2, 3, 4]);
5695
5696 match array {
5697 nums
5698 // ---- `nums` is bound by move.
5699 if nums.iter().sum::<u8>() == 10
5700 // ^------ `.iter()` implicitly takes a reference to `nums`.
5701 => {
5702 drop(nums);
5703 // ----------- Legal as `nums` was bound by move and so we have ownership.
5704 }
5705 _ => unreachable!(),
5706 }
5707 }
5708 ```
5709
5710
5711
5712Compiler
5713--------
5714- [Added tier 3\* support for the `i686-unknown-uefi` target.][64334]
5715- [Added tier 3 support for the `sparc64-unknown-openbsd` target.][63595]
5716- [rustc will now trim code snippets in diagnostics to fit in your terminal.][63402]
5717 **Note** Cargo currently doesn't use this feature. Refer to
5718 [cargo#7315][cargo/7315] to track this feature's progress.
5719- [You can now pass `--show-output` argument to test binaries to print the
5720 output of successful tests.][62600]
5721
5722
5723\* Refer to Rust's [platform support page][platform-support-doc] for more
5724information on Rust's tiered platform support.
5725
5726Libraries
5727---------
5728- [`Vec::new` and `String::new` are now `const` functions.][64028]
5729- [`LinkedList::new` is now a `const` function.][63684]
5730- [`str::len`, `[T]::len` and `str::as_bytes` are now `const` functions.][63770]
5731- [The `abs`, `wrapping_abs`, and `overflowing_abs` numeric functions are
5732 now `const`.][63786]
5733
5734Stabilized APIs
5735---------------
5736- [`Pin::into_inner`]
5737- [`Instant::checked_duration_since`]
5738- [`Instant::saturating_duration_since`]
5739
5740Cargo
5741-----
5742- [You can now publish git dependencies if supplied with a `version`.][cargo/7237]
5743- [The `--all` flag has been renamed to `--workspace`.][cargo/7241] Using
5744 `--all` is now deprecated.
5745
5746Misc
5747----
5748- [You can now pass `-Clinker` to rustdoc to control the linker used
5749 for compiling doctests.][63834]
5750
5751Compatibility Notes
5752-------------------
5753- [Code that was previously accepted by the old borrow checker, but rejected by
5754 the NLL borrow checker is now a hard error in Rust 2018.][63565] This was
5755 previously a warning, and will also become a hard error in the Rust 2015
5756 edition in the 1.40.0 release.
5757- [`rustdoc` now requires `rustc` to be installed and in the same directory to
5758 run tests.][63827] This should improve performance when running a large
5759 amount of doctests.
5760- [The `try!` macro will now issue a deprecation warning.][62672] It is
5761 recommended to use the `?` operator instead.
5762- [`asinh(-0.0)` now correctly returns `-0.0`.][63698] Previously this
5763 returned `0.0`.
5764
5765[62600]: https://github.com/rust-lang/rust/pull/62600/
5766[62672]: https://github.com/rust-lang/rust/pull/62672/
5767[63118]: https://github.com/rust-lang/rust/pull/63118/
5768[63209]: https://github.com/rust-lang/rust/pull/63209/
5769[63402]: https://github.com/rust-lang/rust/pull/63402/
5770[63565]: https://github.com/rust-lang/rust/pull/63565/
5771[63595]: https://github.com/rust-lang/rust/pull/63595/
5772[63684]: https://github.com/rust-lang/rust/pull/63684/
5773[63698]: https://github.com/rust-lang/rust/pull/63698/
5774[63770]: https://github.com/rust-lang/rust/pull/63770/
5775[63786]: https://github.com/rust-lang/rust/pull/63786/
5776[63827]: https://github.com/rust-lang/rust/pull/63827/
5777[63834]: https://github.com/rust-lang/rust/pull/63834/
5778[64010]: https://github.com/rust-lang/rust/pull/64010/
5779[64028]: https://github.com/rust-lang/rust/pull/64028/
5780[64334]: https://github.com/rust-lang/rust/pull/64334/
5781[cargo/7237]: https://github.com/rust-lang/cargo/pull/7237/
5782[cargo/7241]: https://github.com/rust-lang/cargo/pull/7241/
5783[cargo/7315]: https://github.com/rust-lang/cargo/pull/7315/
5784[`Pin::into_inner`]: https://doc.rust-lang.org/std/pin/struct.Pin.html#method.into_inner
5785[`Instant::checked_duration_since`]: https://doc.rust-lang.org/std/time/struct.Instant.html#method.checked_duration_since
5786[`Instant::saturating_duration_since`]: https://doc.rust-lang.org/std/time/struct.Instant.html#method.saturating_duration_since
5787
5788Version 1.38.0 (2019-09-26)
5789==========================
5790
5791Language
5792--------
5793- [The `#[global_allocator]` attribute can now be used in submodules.][62735]
5794- [The `#[deprecated]` attribute can now be used on macros.][62042]
5795
5796Compiler
5797--------
5798- [Added pipelined compilation support to `rustc`.][62766] This will
5799 improve compilation times in some cases. For further information please refer
5800 to the [_"Evaluating pipelined rustc compilation"_][pipeline-internals] thread.
5801- [Added tier 3\* support for the `aarch64-uwp-windows-msvc`, `i686-uwp-windows-gnu`,
5802 `i686-uwp-windows-msvc`, `x86_64-uwp-windows-gnu`, and
5803 `x86_64-uwp-windows-msvc` targets.][60260]
5804- [Added tier 3 support for the `armv7-unknown-linux-gnueabi` and
5805 `armv7-unknown-linux-musleabi` targets.][63107]
5806- [Added tier 3 support for the `hexagon-unknown-linux-musl` target.][62814]
5807- [Added tier 3 support for the `riscv32i-unknown-none-elf` target.][62784]
5808- [Upgraded to LLVM 9.][62592]
5809
5810\* Refer to Rust's [platform support page][platform-support-doc] for more
5811information on Rust's tiered platform support.
5812
5813Libraries
5814---------
5815- [`ascii::EscapeDefault` now implements `Clone` and `Display`.][63421]
5816- [Derive macros for prelude traits (e.g. `Clone`, `Debug`, `Hash`) are now
5817 available at the same path as the trait.][63056] (e.g. The `Clone` derive macro
5818 is available at `std::clone::Clone`). This also makes all built-in macros
5819 available in `std`/`core` root. e.g. `std::include_bytes!`.
5820- [`str::Chars` now implements `Debug`.][63000]
5821- [`slice::{concat, connect, join}` now accepts `&[T]` in addition to `&T`.][62528]
5822- [`*const T` and `*mut T` now implement `marker::Unpin`.][62583]
5823- [`Arc<[T]>` and `Rc<[T]>` now implement `FromIterator<T>`.][61953]
5824- [Added euclidean remainder and division operations (`div_euclid`,
5825 `rem_euclid`) to all numeric primitives.][61884] Additionally `checked`,
5826 `overflowing`, and `wrapping` versions are available for all
5827 integer primitives.
5828- [`thread::AccessError` now implements `Clone`, `Copy`, `Eq`, `Error`, and
5829 `PartialEq`.][61491]
5830- [`iter::{StepBy, Peekable, Take}` now implement `DoubleEndedIterator`.][61457]
5831
5832Stabilized APIs
5833---------------
5834- [`<*const T>::cast`]
5835- [`<*mut T>::cast`]
5836- [`Duration::as_secs_f32`]
5837- [`Duration::as_secs_f64`]
5838- [`Duration::div_f32`]
5839- [`Duration::div_f64`]
5840- [`Duration::from_secs_f32`]
5841- [`Duration::from_secs_f64`]
5842- [`Duration::mul_f32`]
5843- [`Duration::mul_f64`]
5844- [`any::type_name`]
5845
5846Cargo
5847-----
5848- [Added pipelined compilation support to `cargo`.][cargo/7143]
5849- [You can now pass the `--features` option multiple times to enable
5850 multiple features.][cargo/7084]
5851
5852Rustdoc
5853-------
5854
5855- [Documentation on `pub use` statements is prepended to the documentation of the re-exported item][63048]
5856
5857Misc
5858----
5859- [`rustc` will now warn about some incorrect uses of
5860 `mem::{uninitialized, zeroed}` that are known to cause undefined behaviour.][63346]
5861
5862Compatibility Notes
5863-------------------
5864- The [`x86_64-unknown-uefi` platform can not be built][62785] with rustc
5865 1.38.0.
5866- The [`armv7-unknown-linux-gnueabihf` platform is known to have
5867 issues][62896] with certain crates such as libc.
5868
5869[60260]: https://github.com/rust-lang/rust/pull/60260/
5870[61457]: https://github.com/rust-lang/rust/pull/61457/
5871[61491]: https://github.com/rust-lang/rust/pull/61491/
5872[61884]: https://github.com/rust-lang/rust/pull/61884/
5873[61953]: https://github.com/rust-lang/rust/pull/61953/
5874[62042]: https://github.com/rust-lang/rust/pull/62042/
5875[62528]: https://github.com/rust-lang/rust/pull/62528/
5876[62583]: https://github.com/rust-lang/rust/pull/62583/
5877[62735]: https://github.com/rust-lang/rust/pull/62735/
5878[62766]: https://github.com/rust-lang/rust/pull/62766/
5879[62784]: https://github.com/rust-lang/rust/pull/62784/
5880[62592]: https://github.com/rust-lang/rust/pull/62592/
5881[62785]: https://github.com/rust-lang/rust/issues/62785/
5882[62814]: https://github.com/rust-lang/rust/pull/62814/
5883[62896]: https://github.com/rust-lang/rust/issues/62896/
5884[63000]: https://github.com/rust-lang/rust/pull/63000/
5885[63056]: https://github.com/rust-lang/rust/pull/63056/
5886[63107]: https://github.com/rust-lang/rust/pull/63107/
5887[63346]: https://github.com/rust-lang/rust/pull/63346/
5888[63421]: https://github.com/rust-lang/rust/pull/63421/
5889[cargo/7084]: https://github.com/rust-lang/cargo/pull/7084/
5890[cargo/7143]: https://github.com/rust-lang/cargo/pull/7143/
5891[63048]: https://github.com/rust-lang/rust/pull/63048
5892[`<*const T>::cast`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.cast
5893[`<*mut T>::cast`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.cast
5894[`Duration::as_secs_f32`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.as_secs_f32
5895[`Duration::as_secs_f64`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.as_secs_f64
5896[`Duration::div_f32`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.div_f32
5897[`Duration::div_f64`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.div_f64
5898[`Duration::from_secs_f32`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.from_secs_f32
5899[`Duration::from_secs_f64`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.from_secs_f64
5900[`Duration::mul_f32`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.mul_f32
5901[`Duration::mul_f64`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.mul_f64
5902[`any::type_name`]: https://doc.rust-lang.org/std/any/fn.type_name.html
5903[platform-support-doc]: https://doc.rust-lang.org/nightly/rustc/platform-support.html
5904[pipeline-internals]: https://internals.rust-lang.org/t/evaluating-pipelined-rustc-compilation/10199
5905
5906Version 1.37.0 (2019-08-15)
5907==========================
5908
5909Language
5910--------
5911- `#[must_use]` will now warn if the type is contained in a [tuple][61100],
5912 [`Box`][62228], or an [array][62235] and unused.
5913- [You can now use the `cfg` and `cfg_attr` attributes on
5914 generic parameters.][61547]
5915- [You can now use enum variants through type alias.][61682] e.g. You can
5916 write the following:
5917 ```rust
5918 type MyOption = Option<u8>;
5919
5920 fn increment_or_zero(x: MyOption) -> u8 {
5921 match x {
5922 MyOption::Some(y) => y + 1,
5923 MyOption::None => 0,
5924 }
5925 }
5926 ```
5927- [You can now use `_` as an identifier for consts.][61347] e.g. You can write
5928 `const _: u32 = 5;`.
5929- [You can now use `#[repr(align(X)]` on enums.][61229]
5930- [The `?` Kleene macro operator is now available in the
5931 2015 edition.][60932]
5932
5933Compiler
5934--------
5935- [You can now enable Profile-Guided Optimization with the `-C profile-generate`
5936 and `-C profile-use` flags.][61268] For more information on how to use profile
5937 guided optimization, please refer to the [rustc book][rustc-book-pgo].
5938- [The `rust-lldb` wrapper script should now work again.][61827]
5939
5940Libraries
5941---------
5942- [`mem::MaybeUninit<T>` is now ABI-compatible with `T`.][61802]
5943
5944Stabilized APIs
5945---------------
5946- [`BufReader::buffer`]
5947- [`BufWriter::buffer`]
5948- [`Cell::from_mut`]
5949- [`Cell<[T]>::as_slice_of_cells`][`Cell<slice>::as_slice_of_cells`]
5950- [`DoubleEndedIterator::nth_back`]
5951- [`Option::xor`]
5952- [`Wrapping::reverse_bits`]
5953- [`i128::reverse_bits`]
5954- [`i16::reverse_bits`]
5955- [`i32::reverse_bits`]
5956- [`i64::reverse_bits`]
5957- [`i8::reverse_bits`]
5958- [`isize::reverse_bits`]
5959- [`slice::copy_within`]
5960- [`u128::reverse_bits`]
5961- [`u16::reverse_bits`]
5962- [`u32::reverse_bits`]
5963- [`u64::reverse_bits`]
5964- [`u8::reverse_bits`]
5965- [`usize::reverse_bits`]
5966
5967Cargo
5968-----
5969- [`Cargo.lock` files are now included by default when publishing executable crates
5970 with executables.][cargo/7026]
5971- [You can now specify `default-run="foo"` in `[package]` to specify the
5972 default executable to use for `cargo run`.][cargo/7056]
5973
5974Misc
5975----
5976
5977Compatibility Notes
5978-------------------
5979- [Using `...` for inclusive range patterns will now warn by default.][61342]
5980 Please transition your code to using the `..=` syntax for inclusive
5981 ranges instead.
5982- [Using a trait object without the `dyn` will now warn by default.][61203]
5983 Please transition your code to use `dyn Trait` for trait objects instead.
5984
5985[62228]: https://github.com/rust-lang/rust/pull/62228/
5986[62235]: https://github.com/rust-lang/rust/pull/62235/
5987[61802]: https://github.com/rust-lang/rust/pull/61802/
5988[61827]: https://github.com/rust-lang/rust/pull/61827/
5989[61547]: https://github.com/rust-lang/rust/pull/61547/
5990[61682]: https://github.com/rust-lang/rust/pull/61682/
5991[61268]: https://github.com/rust-lang/rust/pull/61268/
5992[61342]: https://github.com/rust-lang/rust/pull/61342/
5993[61347]: https://github.com/rust-lang/rust/pull/61347/
5994[61100]: https://github.com/rust-lang/rust/pull/61100/
5995[61203]: https://github.com/rust-lang/rust/pull/61203/
5996[61229]: https://github.com/rust-lang/rust/pull/61229/
5997[60932]: https://github.com/rust-lang/rust/pull/60932/
5998[cargo/7026]: https://github.com/rust-lang/cargo/pull/7026/
5999[cargo/7056]: https://github.com/rust-lang/cargo/pull/7056/
6000[`BufReader::buffer`]: https://doc.rust-lang.org/std/io/struct.BufReader.html#method.buffer
6001[`BufWriter::buffer`]: https://doc.rust-lang.org/std/io/struct.BufWriter.html#method.buffer
6002[`Cell::from_mut`]: https://doc.rust-lang.org/std/cell/struct.Cell.html#method.from_mut
6003[`Cell<slice>::as_slice_of_cells`]: https://doc.rust-lang.org/std/cell/struct.Cell.html#method.as_slice_of_cells
6004[`DoubleEndedIterator::nth_back`]: https://doc.rust-lang.org/std/iter/trait.DoubleEndedIterator.html#method.nth_back
6005[`Option::xor`]: https://doc.rust-lang.org/std/option/enum.Option.html#method.xor
6006[`Wrapping::reverse_bits`]: https://doc.rust-lang.org/std/num/struct.Wrapping.html#method.reverse_bits
6007[`i128::reverse_bits`]: https://doc.rust-lang.org/std/primitive.i128.html#method.reverse_bits
6008[`i16::reverse_bits`]: https://doc.rust-lang.org/std/primitive.i16.html#method.reverse_bits
6009[`i32::reverse_bits`]: https://doc.rust-lang.org/std/primitive.i32.html#method.reverse_bits
6010[`i64::reverse_bits`]: https://doc.rust-lang.org/std/primitive.i64.html#method.reverse_bits
6011[`i8::reverse_bits`]: https://doc.rust-lang.org/std/primitive.i8.html#method.reverse_bits
6012[`isize::reverse_bits`]: https://doc.rust-lang.org/std/primitive.isize.html#method.reverse_bits
6013[`slice::copy_within`]: https://doc.rust-lang.org/std/primitive.slice.html#method.copy_within
6014[`u128::reverse_bits`]: https://doc.rust-lang.org/std/primitive.u128.html#method.reverse_bits
6015[`u16::reverse_bits`]: https://doc.rust-lang.org/std/primitive.u16.html#method.reverse_bits
6016[`u32::reverse_bits`]: https://doc.rust-lang.org/std/primitive.u32.html#method.reverse_bits
6017[`u64::reverse_bits`]: https://doc.rust-lang.org/std/primitive.u64.html#method.reverse_bits
6018[`u8::reverse_bits`]: https://doc.rust-lang.org/std/primitive.u8.html#method.reverse_bits
6019[`usize::reverse_bits`]: https://doc.rust-lang.org/std/primitive.usize.html#method.reverse_bits
6020[rustc-book-pgo]: https://doc.rust-lang.org/rustc/profile-guided-optimization.html
6021
6022
6023Version 1.36.0 (2019-07-04)
6024==========================
6025
6026Language
6027--------
6028- [Non-Lexical Lifetimes are now enabled on the 2015 edition.][59114]
6029- [The order of traits in trait objects no longer affects the semantics of that
6030 object.][59445] e.g. `dyn Send + fmt::Debug` is now equivalent to
6031 `dyn fmt::Debug + Send`, where this was previously not the case.
6032
6033Libraries
6034---------
6035- [`HashMap`'s implementation has been replaced with `hashbrown::HashMap` implementation.][58623]
6036- [`TryFromSliceError` now implements `From<Infallible>`.][60318]
6037- [`mem::needs_drop` is now available as a const fn.][60364]
6038- [`alloc::Layout::from_size_align_unchecked` is now available as a const fn.][60370]
6039- [`String` now implements `BorrowMut<str>`.][60404]
6040- [`io::Cursor` now implements `Default`.][60234]
6041- [Both `NonNull::{dangling, cast}` are now const fns.][60244]
6042- [The `alloc` crate is now stable.][59675] `alloc` allows you to use a subset
6043 of `std` (e.g. `Vec`, `Box`, `Arc`) in `#![no_std]` environments if the
6044 environment has access to heap memory allocation.
6045- [`String` now implements `From<&String>`.][59825]
6046- [You can now pass multiple arguments to the `dbg!` macro.][59826] `dbg!` will
6047 return a tuple of each argument when there is multiple arguments.
6048- [`Result::{is_err, is_ok}` are now `#[must_use]` and will produce a warning if
6049 not used.][59648]
6050
6051Stabilized APIs
6052---------------
6053- [`VecDeque::rotate_left`]
6054- [`VecDeque::rotate_right`]
6055- [`Iterator::copied`]
6056- [`io::IoSlice`]
6057- [`io::IoSliceMut`]
6058- [`Read::read_vectored`]
6059- [`Write::write_vectored`]
6060- [`str::as_mut_ptr`]
6061- [`mem::MaybeUninit`]
6062- [`pointer::align_offset`]
6063- [`future::Future`]
6064- [`task::Context`]
6065- [`task::RawWaker`]
6066- [`task::RawWakerVTable`]
6067- [`task::Waker`]
6068- [`task::Poll`]
6069
6070Cargo
6071-----
6072- [Cargo will now produce an error if you attempt to use the name of a required dependency as a feature.][cargo/6860]
6073- [You can now pass the `--offline` flag to run cargo without accessing the network.][cargo/6934]
6074
6075You can find further change's in [Cargo's 1.36.0 release notes][cargo-1-36-0].
6076
6077Clippy
6078------
6079There have been numerous additions and fixes to clippy, see [Clippy's 1.36.0 release notes][clippy-1-36-0] for more details.
6080
6081Misc
6082----
6083
6084Compatibility Notes
6085-------------------
6086- With the stabilisation of `mem::MaybeUninit`, `mem::uninitialized` use is no
6087 longer recommended, and will be deprecated in 1.39.0.
6088
6089[60318]: https://github.com/rust-lang/rust/pull/60318/
6090[60364]: https://github.com/rust-lang/rust/pull/60364/
6091[60370]: https://github.com/rust-lang/rust/pull/60370/
6092[60404]: https://github.com/rust-lang/rust/pull/60404/
6093[60234]: https://github.com/rust-lang/rust/pull/60234/
6094[60244]: https://github.com/rust-lang/rust/pull/60244/
6095[58623]: https://github.com/rust-lang/rust/pull/58623/
6096[59648]: https://github.com/rust-lang/rust/pull/59648/
6097[59675]: https://github.com/rust-lang/rust/pull/59675/
6098[59825]: https://github.com/rust-lang/rust/pull/59825/
6099[59826]: https://github.com/rust-lang/rust/pull/59826/
6100[59445]: https://github.com/rust-lang/rust/pull/59445/
6101[59114]: https://github.com/rust-lang/rust/pull/59114/
6102[cargo/6860]: https://github.com/rust-lang/cargo/pull/6860/
6103[cargo/6934]: https://github.com/rust-lang/cargo/pull/6934/
6104[`VecDeque::rotate_left`]: https://doc.rust-lang.org/std/collections/struct.VecDeque.html#method.rotate_left
6105[`VecDeque::rotate_right`]: https://doc.rust-lang.org/std/collections/struct.VecDeque.html#method.rotate_right
6106[`Iterator::copied`]: https://doc.rust-lang.org/std/iter/trait.Iterator.html#tymethod.copied
6107[`io::IoSlice`]: https://doc.rust-lang.org/std/io/struct.IoSlice.html
6108[`io::IoSliceMut`]: https://doc.rust-lang.org/std/io/struct.IoSliceMut.html
6109[`Read::read_vectored`]: https://doc.rust-lang.org/std/io/trait.Read.html#method.read_vectored
6110[`Write::write_vectored`]: https://doc.rust-lang.org/std/io/trait.Write.html#method.write_vectored
6111[`str::as_mut_ptr`]: https://doc.rust-lang.org/std/primitive.str.html#method.as_mut_ptr
6112[`mem::MaybeUninit`]: https://doc.rust-lang.org/std/mem/union.MaybeUninit.html
6113[`pointer::align_offset`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.align_offset
6114[`future::Future`]: https://doc.rust-lang.org/std/future/trait.Future.html
6115[`task::Context`]: https://doc.rust-lang.org/beta/std/task/struct.Context.html
6116[`task::RawWaker`]: https://doc.rust-lang.org/beta/std/task/struct.RawWaker.html
6117[`task::RawWakerVTable`]: https://doc.rust-lang.org/beta/std/task/struct.RawWakerVTable.html
6118[`task::Waker`]: https://doc.rust-lang.org/beta/std/task/struct.Waker.html
6119[`task::Poll`]: https://doc.rust-lang.org/beta/std/task/enum.Poll.html
6120[clippy-1-36-0]: https://github.com/rust-lang/rust-clippy/blob/master/CHANGELOG.md#rust-136
6121[cargo-1-36-0]: https://github.com/rust-lang/cargo/blob/master/CHANGELOG.md#cargo-136-2019-07-04
6122
6123
6124Version 1.35.0 (2019-05-23)
6125==========================
6126
6127Language
6128--------
6129- [`FnOnce`, `FnMut`, and the `Fn` traits are now implemented for `Box<FnOnce>`,
6130 `Box<FnMut>`, and `Box<Fn>` respectively.][59500]
6131- [You can now coerce closures into unsafe function pointers.][59580] e.g.
6132 ```rust
6133 unsafe fn call_unsafe(func: unsafe fn()) {
6134 func()
6135 }
6136
6137 pub fn main() {
6138 unsafe { call_unsafe(|| {}); }
6139 }
6140 ```
6141
6142
6143Compiler
6144--------
6145- [Added the `armv6-unknown-freebsd-gnueabihf` and
6146 `armv7-unknown-freebsd-gnueabihf` targets.][58080]
6147- [Added the `wasm32-unknown-wasi` target.][59464]
6148
6149
6150Libraries
6151---------
6152- [`Thread` will now show its ID in `Debug` output.][59460]
6153- [`StdinLock`, `StdoutLock`, and `StderrLock` now implement `AsRawFd`.][59512]
6154- [`alloc::System` now implements `Default`.][59451]
6155- [Expanded `Debug` output (`{:#?}`) for structs now has a trailing comma on the
6156 last field.][59076]
6157- [`char::{ToLowercase, ToUppercase}` now
6158 implement `ExactSizeIterator`.][58778]
6159- [All `NonZero` numeric types now implement `FromStr`.][58717]
6160- [Removed the `Read` trait bounds
6161 on the `BufReader::{get_ref, get_mut, into_inner}` methods.][58423]
6162- [You can now call the `dbg!` macro without any parameters to print the file
6163 and line where it is called.][57847]
6164- [In place ASCII case conversions are now up to 4× faster.][59283]
6165 e.g. `str::make_ascii_lowercase`
6166- [`hash_map::{OccupiedEntry, VacantEntry}` now implement `Sync`
6167 and `Send`.][58369]
6168
6169Stabilized APIs
6170---------------
6171- [`f32::copysign`]
6172- [`f64::copysign`]
6173- [`RefCell::replace_with`]
6174- [`RefCell::map_split`]
6175- [`ptr::hash`]
6176- [`Range::contains`]
6177- [`RangeFrom::contains`]
6178- [`RangeTo::contains`]
6179- [`RangeInclusive::contains`]
6180- [`RangeToInclusive::contains`]
6181- [`Option::copied`]
6182
6183Cargo
6184-----
6185- [You can now set `cargo:rustc-cdylib-link-arg` at build time to pass custom
6186 linker arguments when building a `cdylib`.][cargo/6298] Its usage is highly
6187 platform specific.
6188
6189Misc
6190----
6191- [The Rust toolchain is now available natively for musl based distros.][58575]
6192
6193[59460]: https://github.com/rust-lang/rust/pull/59460/
6194[59464]: https://github.com/rust-lang/rust/pull/59464/
6195[59500]: https://github.com/rust-lang/rust/pull/59500/
6196[59512]: https://github.com/rust-lang/rust/pull/59512/
6197[59580]: https://github.com/rust-lang/rust/pull/59580/
6198[59283]: https://github.com/rust-lang/rust/pull/59283/
6199[59451]: https://github.com/rust-lang/rust/pull/59451/
6200[59076]: https://github.com/rust-lang/rust/pull/59076/
6201[58778]: https://github.com/rust-lang/rust/pull/58778/
6202[58717]: https://github.com/rust-lang/rust/pull/58717/
6203[58369]: https://github.com/rust-lang/rust/pull/58369/
6204[58423]: https://github.com/rust-lang/rust/pull/58423/
6205[58080]: https://github.com/rust-lang/rust/pull/58080/
6206[57847]: https://github.com/rust-lang/rust/pull/57847/
6207[58575]: https://github.com/rust-lang/rust/pull/58575
6208[cargo/6298]: https://github.com/rust-lang/cargo/pull/6298/
6209[`f32::copysign`]: https://doc.rust-lang.org/stable/std/primitive.f32.html#method.copysign
6210[`f64::copysign`]: https://doc.rust-lang.org/stable/std/primitive.f64.html#method.copysign
6211[`RefCell::replace_with`]: https://doc.rust-lang.org/stable/std/cell/struct.RefCell.html#method.replace_with
6212[`RefCell::map_split`]: https://doc.rust-lang.org/stable/std/cell/struct.RefCell.html#method.map_split
6213[`ptr::hash`]: https://doc.rust-lang.org/stable/std/ptr/fn.hash.html
6214[`Range::contains`]: https://doc.rust-lang.org/std/ops/struct.Range.html#method.contains
6215[`RangeFrom::contains`]: https://doc.rust-lang.org/std/ops/struct.RangeFrom.html#method.contains
6216[`RangeTo::contains`]: https://doc.rust-lang.org/std/ops/struct.RangeTo.html#method.contains
6217[`RangeInclusive::contains`]: https://doc.rust-lang.org/std/ops/struct.RangeInclusive.html#method.contains
6218[`RangeToInclusive::contains`]: https://doc.rust-lang.org/std/ops/struct.RangeToInclusive.html#method.contains
6219[`Option::copied`]: https://doc.rust-lang.org/std/option/enum.Option.html#method.copied
6220
6221Version 1.34.2 (2019-05-14)
6222===========================
6223
6224* [Destabilize the `Error::type_id` function due to a security
6225 vulnerability][60785] ([CVE-2019-12083])
6226
6227[60785]: https://github.com/rust-lang/rust/pull/60785
6228[CVE-2019-12083]: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-12083
6229
6230Version 1.34.1 (2019-04-25)
6231===========================
6232
6233* [Fix false positives for the `redundant_closure` Clippy lint][clippy/3821]
6234* [Fix false positives for the `missing_const_for_fn` Clippy lint][clippy/3844]
6235* [Fix Clippy panic when checking some macros][clippy/3805]
6236
6237[clippy/3821]: https://github.com/rust-lang/rust-clippy/pull/3821
6238[clippy/3844]: https://github.com/rust-lang/rust-clippy/pull/3844
6239[clippy/3805]: https://github.com/rust-lang/rust-clippy/pull/3805
6240
6241Version 1.34.0 (2019-04-11)
6242==========================
6243
6244Language
6245--------
6246- [You can now use `#[deprecated = "reason"]`][58166] as a shorthand for
6247 `#[deprecated(note = "reason")]`. This was previously allowed by mistake
6248 but had no effect.
6249- [You can now accept token streams in `#[attr()]`,`#[attr[]]`, and
6250 `#[attr{}]` procedural macros.][57367]
6251- [You can now write `extern crate self as foo;`][57407] to import your
6252 crate's root into the extern prelude.
6253
6254
6255Compiler
6256--------
6257- [You can now target `riscv64imac-unknown-none-elf` and
6258 `riscv64gc-unknown-none-elf`.][58406]
6259- [You can now enable linker plugin LTO optimisations with
6260 `-C linker-plugin-lto`.][58057] This allows rustc to compile your Rust code
6261 into LLVM bitcode allowing LLVM to perform LTO optimisations across C/C++ FFI
6262 boundaries.
6263- [You can now target `powerpc64-unknown-freebsd`.][57809]
6264
6265
6266Libraries
6267---------
6268- [The trait bounds have been removed on some of `HashMap<K, V, S>`'s and
6269 `HashSet<T, S>`'s basic methods.][58370] Most notably you no longer require
6270 the `Hash` trait to create an iterator.
6271- [The `Ord` trait bounds have been removed on some of `BinaryHeap<T>`'s basic
6272 methods.][58421] Most notably you no longer require the `Ord` trait to create
6273 an iterator.
6274- [The methods `overflowing_neg` and `wrapping_neg` are now `const` functions
6275 for all numeric types.][58044]
6276- [Indexing a `str` is now generic over all types that
6277 implement `SliceIndex<str>`.][57604]
6278- [`str::trim`, `str::trim_matches`, `str::trim_{start, end}`, and
6279 `str::trim_{start, end}_matches` are now `#[must_use]`][57106] and will
6280 produce a warning if their returning type is unused.
6281- [The methods `checked_pow`, `saturating_pow`, `wrapping_pow`, and
6282 `overflowing_pow` are now available for all numeric types.][57873] These are
6283 equivalent to methods such as `wrapping_add` for the `pow` operation.
6284
6285
6286Stabilized APIs
6287---------------
6288
6289#### std & core
6290* [`Any::type_id`]
6291* [`Error::type_id`]
6292* [`atomic::AtomicI16`]
6293* [`atomic::AtomicI32`]
6294* [`atomic::AtomicI64`]
6295* [`atomic::AtomicI8`]
6296* [`atomic::AtomicU16`]
6297* [`atomic::AtomicU32`]
6298* [`atomic::AtomicU64`]
6299* [`atomic::AtomicU8`]
6300* [`convert::Infallible`]
6301* [`convert::TryFrom`]
6302* [`convert::TryInto`]
6303* [`iter::from_fn`]
6304* [`iter::successors`]
6305* [`num::NonZeroI128`]
6306* [`num::NonZeroI16`]
6307* [`num::NonZeroI32`]
6308* [`num::NonZeroI64`]
6309* [`num::NonZeroI8`]
6310* [`num::NonZeroIsize`]
6311* [`slice::sort_by_cached_key`]
6312* [`str::escape_debug`]
6313* [`str::escape_default`]
6314* [`str::escape_unicode`]
6315* [`str::split_ascii_whitespace`]
6316
6317#### std
6318* [`Instant::checked_add`]
6319* [`Instant::checked_sub`]
6320* [`SystemTime::checked_add`]
6321* [`SystemTime::checked_sub`]
6322
6323Cargo
6324-----
6325- [You can now use alternative registries to crates.io.][cargo/6654]
6326
6327Misc
6328----
6329- [You can now use the `?` operator in your documentation tests without manually
6330 adding `fn main() -> Result<(), _> {}`.][56470]
6331
6332Compatibility Notes
6333-------------------
6334- [`Command::before_exec` is being replaced by the unsafe method
6335 `Command::pre_exec`][58059] and will be deprecated with Rust 1.37.0.
6336- [Use of `ATOMIC_{BOOL, ISIZE, USIZE}_INIT` is now deprecated][57425] as you
6337 can now use `const` functions in `static` variables.
6338
6339[58370]: https://github.com/rust-lang/rust/pull/58370/
6340[58406]: https://github.com/rust-lang/rust/pull/58406/
6341[58421]: https://github.com/rust-lang/rust/pull/58421/
6342[58166]: https://github.com/rust-lang/rust/pull/58166/
6343[58044]: https://github.com/rust-lang/rust/pull/58044/
6344[58057]: https://github.com/rust-lang/rust/pull/58057/
6345[58059]: https://github.com/rust-lang/rust/pull/58059/
6346[57809]: https://github.com/rust-lang/rust/pull/57809/
6347[57873]: https://github.com/rust-lang/rust/pull/57873/
6348[57604]: https://github.com/rust-lang/rust/pull/57604/
6349[57367]: https://github.com/rust-lang/rust/pull/57367/
6350[57407]: https://github.com/rust-lang/rust/pull/57407/
6351[57425]: https://github.com/rust-lang/rust/pull/57425/
6352[57106]: https://github.com/rust-lang/rust/pull/57106/
6353[56470]: https://github.com/rust-lang/rust/pull/56470/
6354[cargo/6654]: https://github.com/rust-lang/cargo/pull/6654/
6355[`Any::type_id`]: https://doc.rust-lang.org/std/any/trait.Any.html#tymethod.type_id
6356[`Error::type_id`]: https://doc.rust-lang.org/std/error/trait.Error.html#method.type_id
6357[`atomic::AtomicI16`]: https://doc.rust-lang.org/std/sync/atomic/struct.AtomicI16.html
6358[`atomic::AtomicI32`]: https://doc.rust-lang.org/std/sync/atomic/struct.AtomicI32.html
6359[`atomic::AtomicI64`]: https://doc.rust-lang.org/std/sync/atomic/struct.AtomicI64.html
6360[`atomic::AtomicI8`]: https://doc.rust-lang.org/std/sync/atomic/struct.AtomicI8.html
6361[`atomic::AtomicU16`]: https://doc.rust-lang.org/std/sync/atomic/struct.AtomicU16.html
6362[`atomic::AtomicU32`]: https://doc.rust-lang.org/std/sync/atomic/struct.AtomicU32.html
6363[`atomic::AtomicU64`]: https://doc.rust-lang.org/std/sync/atomic/struct.AtomicU64.html
6364[`atomic::AtomicU8`]: https://doc.rust-lang.org/std/sync/atomic/struct.AtomicU8.html
6365[`convert::Infallible`]: https://doc.rust-lang.org/std/convert/enum.Infallible.html
6366[`convert::TryFrom`]: https://doc.rust-lang.org/std/convert/trait.TryFrom.html
6367[`convert::TryInto`]: https://doc.rust-lang.org/std/convert/trait.TryInto.html
6368[`iter::from_fn`]: https://doc.rust-lang.org/std/iter/fn.from_fn.html
6369[`iter::successors`]: https://doc.rust-lang.org/std/iter/fn.successors.html
6370[`num::NonZeroI128`]: https://doc.rust-lang.org/std/num/struct.NonZeroI128.html
6371[`num::NonZeroI16`]: https://doc.rust-lang.org/std/num/struct.NonZeroI16.html
6372[`num::NonZeroI32`]: https://doc.rust-lang.org/std/num/struct.NonZeroI32.html
6373[`num::NonZeroI64`]: https://doc.rust-lang.org/std/num/struct.NonZeroI64.html
6374[`num::NonZeroI8`]: https://doc.rust-lang.org/std/num/struct.NonZeroI8.html
6375[`num::NonZeroIsize`]: https://doc.rust-lang.org/std/num/struct.NonZeroIsize.html
6376[`slice::sort_by_cached_key`]: https://doc.rust-lang.org/std/primitive.slice.html#method.sort_by_cached_key
6377[`str::escape_debug`]: https://doc.rust-lang.org/std/primitive.str.html#method.escape_debug
6378[`str::escape_default`]: https://doc.rust-lang.org/std/primitive.str.html#method.escape_default
6379[`str::escape_unicode`]: https://doc.rust-lang.org/std/primitive.str.html#method.escape_unicode
6380[`str::split_ascii_whitespace`]: https://doc.rust-lang.org/std/primitive.str.html#method.split_ascii_whitespace
6381[`Instant::checked_add`]: https://doc.rust-lang.org/std/time/struct.Instant.html#method.checked_add
6382[`Instant::checked_sub`]: https://doc.rust-lang.org/std/time/struct.Instant.html#method.checked_sub
6383[`SystemTime::checked_add`]: https://doc.rust-lang.org/std/time/struct.SystemTime.html#method.checked_add
6384[`SystemTime::checked_sub`]: https://doc.rust-lang.org/std/time/struct.SystemTime.html#method.checked_sub
6385
6386
6387Version 1.33.0 (2019-02-28)
6388==========================
6389
6390Language
6391--------
6392- [You can now use the `cfg(target_vendor)` attribute.][57465] E.g.
6393 `#[cfg(target_vendor="apple")] fn main() { println!("Hello Apple!"); }`
6394- [Integer patterns such as in a match expression can now be exhaustive.][56362]
6395 E.g. You can have match statement on a `u8` that covers `0..=255` and
6396 you would no longer be required to have a `_ => unreachable!()` case.
6397- [You can now have multiple patterns in `if let` and `while let`
6398 expressions.][57532] You can do this with the same syntax as a `match`
6399 expression. E.g.
6400 ```rust
6401 enum Creature {
6402 Crab(String),
6403 Lobster(String),
6404 Person(String),
6405 }
6406
6407 fn main() {
6408 let state = Creature::Crab("Ferris");
6409
6410 if let Creature::Crab(name) | Creature::Person(name) = state {
6411 println!("This creature's name is: {}", name);
6412 }
6413 }
6414 ```
6415- [You can now have irrefutable `if let` and `while let` patterns.][57535] Using
6416 this feature will by default produce a warning as this behaviour can be
6417 unintuitive. E.g. `if let _ = 5 {}`
6418- [You can now use `let` bindings, assignments, expression statements,
6419 and irrefutable pattern destructuring in const functions.][57175]
6420- [You can now call unsafe const functions.][57067] E.g.
6421 ```rust
6422 const unsafe fn foo() -> i32 { 5 }
6423 const fn bar() -> i32 {
6424 unsafe { foo() }
6425 }
6426 ```
6427- [You can now specify multiple attributes in a `cfg_attr` attribute.][57332]
6428 E.g. `#[cfg_attr(all(), must_use, optimize)]`
6429- [You can now specify a specific alignment with the `#[repr(packed)]`
6430 attribute.][57049] E.g. `#[repr(packed(2))] struct Foo(i16, i32);` is a struct
6431 with an alignment of 2 bytes and a size of 6 bytes.
6432- [You can now import an item from a module as an `_`.][56303] This allows you to
6433 import a trait's impls, and not have the name in the namespace. E.g.
6434 ```rust
6435 use std::io::Read as _;
6436
6437 // Allowed as there is only one `Read` in the module.
6438 pub trait Read {}
6439 ```
6440- [You may now use `Rc`, `Arc`, and `Pin` as method receivers][56805].
6441
6442Compiler
6443--------
6444- [You can now set a linker flavor for `rustc` with the `-Clinker-flavor`
6445 command line argument.][56351]
6446- [The minimum required LLVM version has been bumped to 6.0.][56642]
6447- [Added support for the PowerPC64 architecture on FreeBSD.][57615]
6448- [The `x86_64-fortanix-unknown-sgx` target support has been upgraded to
6449 tier 2 support.][57130] Visit the [platform support][platform-support] page for
6450 information on Rust's platform support.
6451- [Added support for the `thumbv7neon-linux-androideabi` and
6452 `thumbv7neon-unknown-linux-gnueabihf` targets.][56947]
6453- [Added support for the `x86_64-unknown-uefi` target.][56769]
6454
6455Libraries
6456---------
6457- [The methods `overflowing_{add, sub, mul, shl, shr}` are now `const`
6458 functions for all numeric types.][57566]
6459- [The methods `rotate_left`, `rotate_right`, and `wrapping_{add, sub, mul, shl, shr}`
6460 are now `const` functions for all numeric types.][57105]
6461- [The methods `is_positive` and `is_negative` are now `const` functions for
6462 all signed numeric types.][57105]
6463- [The `get` method for all `NonZero` types is now `const`.][57167]
6464- [The methods `count_ones`, `count_zeros`, `leading_zeros`, `trailing_zeros`,
6465 `swap_bytes`, `from_be`, `from_le`, `to_be`, `to_le` are now `const` for all
6466 numeric types.][57234]
6467- [`Ipv4Addr::new` is now a `const` function][57234]
6468
6469Stabilized APIs
6470---------------
6471- [`unix::FileExt::read_exact_at`]
6472- [`unix::FileExt::write_all_at`]
6473- [`Option::transpose`]
6474- [`Result::transpose`]
6475- [`convert::identity`]
6476- [`pin::Pin`]
6477- [`marker::Unpin`]
6478- [`marker::PhantomPinned`]
6479- [`Vec::resize_with`]
6480- [`VecDeque::resize_with`]
6481- [`Duration::as_millis`]
6482- [`Duration::as_micros`]
6483- [`Duration::as_nanos`]
6484
6485
6486Cargo
6487-----
6488- [You can now publish crates that require a feature flag to compile with
6489 `cargo publish --features` or `cargo publish --all-features`.][cargo/6453]
6490- [Cargo should now rebuild a crate if a file was modified during the initial
6491 build.][cargo/6484]
6492
6493Compatibility Notes
6494-------------------
6495- The methods `str::{trim_left, trim_right, trim_left_matches, trim_right_matches}`
6496 are now deprecated in the standard library, and their usage will now produce a warning.
6497 Please use the `str::{trim_start, trim_end, trim_start_matches, trim_end_matches}`
6498 methods instead.
6499- The `Error::cause` method has been deprecated in favor of `Error::source` which supports
6500 downcasting.
6501- [Libtest no longer creates a new thread for each test when
6502 `--test-threads=1`. It also runs the tests in deterministic order][56243]
6503
6504[56243]: https://github.com/rust-lang/rust/pull/56243
6505[56303]: https://github.com/rust-lang/rust/pull/56303/
6506[56351]: https://github.com/rust-lang/rust/pull/56351/
6507[56362]: https://github.com/rust-lang/rust/pull/56362
6508[56642]: https://github.com/rust-lang/rust/pull/56642/
6509[56769]: https://github.com/rust-lang/rust/pull/56769/
6510[56805]: https://github.com/rust-lang/rust/pull/56805
6511[56947]: https://github.com/rust-lang/rust/pull/56947/
6512[57049]: https://github.com/rust-lang/rust/pull/57049/
6513[57067]: https://github.com/rust-lang/rust/pull/57067/
6514[57105]: https://github.com/rust-lang/rust/pull/57105
6515[57130]: https://github.com/rust-lang/rust/pull/57130/
6516[57167]: https://github.com/rust-lang/rust/pull/57167/
6517[57175]: https://github.com/rust-lang/rust/pull/57175/
6518[57234]: https://github.com/rust-lang/rust/pull/57234/
6519[57332]: https://github.com/rust-lang/rust/pull/57332/
6520[57465]: https://github.com/rust-lang/rust/pull/57465/
6521[57532]: https://github.com/rust-lang/rust/pull/57532/
6522[57535]: https://github.com/rust-lang/rust/pull/57535/
6523[57566]: https://github.com/rust-lang/rust/pull/57566/
6524[57615]: https://github.com/rust-lang/rust/pull/57615/
6525[cargo/6453]: https://github.com/rust-lang/cargo/pull/6453/
6526[cargo/6484]: https://github.com/rust-lang/cargo/pull/6484/
6527[`unix::FileExt::read_exact_at`]: https://doc.rust-lang.org/std/os/unix/fs/trait.FileExt.html#method.read_exact_at
6528[`unix::FileExt::write_all_at`]: https://doc.rust-lang.org/std/os/unix/fs/trait.FileExt.html#method.write_all_at
6529[`Option::transpose`]: https://doc.rust-lang.org/std/option/enum.Option.html#method.transpose
6530[`Result::transpose`]: https://doc.rust-lang.org/std/result/enum.Result.html#method.transpose
6531[`convert::identity`]: https://doc.rust-lang.org/std/convert/fn.identity.html
6532[`pin::Pin`]: https://doc.rust-lang.org/std/pin/struct.Pin.html
6533[`marker::Unpin`]: https://doc.rust-lang.org/stable/std/marker/trait.Unpin.html
6534[`marker::PhantomPinned`]: https://doc.rust-lang.org/nightly/std/marker/struct.PhantomPinned.html
6535[`Vec::resize_with`]: https://doc.rust-lang.org/std/vec/struct.Vec.html#method.resize_with
6536[`VecDeque::resize_with`]: https://doc.rust-lang.org/std/collections/struct.VecDeque.html#method.resize_with
6537[`Duration::as_millis`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.as_millis
6538[`Duration::as_micros`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.as_micros
6539[`Duration::as_nanos`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.as_nanos
6540[platform-support]: https://forge.rust-lang.org/platform-support.html
6541
6542Version 1.32.0 (2019-01-17)
6543==========================
6544
6545Language
6546--------
6547#### 2018 edition
6548- [You can now use the `?` operator in macro definitions.][56245] The `?`
6549 operator allows you to specify zero or one repetitions similar to the `*` and
6550 `+` operators.
6551- [Module paths with no leading keyword like `super`, `self`, or `crate`, will
6552 now always resolve to the item (`enum`, `struct`, etc.) available in the
6553 module if present, before resolving to a external crate or an item the prelude.][56759]
6554 E.g.
6555 ```rust
6556 enum Color { Red, Green, Blue }
6557
6558 use Color::*;
6559 ```
6560
6561#### All editions
6562- [You can now match against `PhantomData<T>` types.][55837]
6563- [You can now match against literals in macros with the `literal`
6564 specifier.][56072] This will match against a literal of any type.
6565 E.g. `1`, `'A'`, `"Hello World"`
6566- [Self can now be used as a constructor and pattern for unit and tuple structs.][56365] E.g.
6567 ```rust
6568 struct Point(i32, i32);
6569
6570 impl Point {
6571 pub fn new(x: i32, y: i32) -> Self {
6572 Self(x, y)
6573 }
6574
6575 pub fn is_origin(&self) -> bool {
6576 match self {
6577 Self(0, 0) => true,
6578 _ => false,
6579 }
6580 }
6581 }
6582 ```
6583- [Self can also now be used in type definitions.][56366] E.g.
6584 ```rust
6585 enum List<T>
6586 where
6587 Self: PartialOrd<Self> // can write `Self` instead of `List<T>`
6588 {
6589 Nil,
6590 Cons(T, Box<Self>) // likewise here
6591 }
6592 ```
6593- [You can now mark traits with `#[must_use]`.][55663] This provides a warning if
6594 a `impl Trait` or `dyn Trait` is returned and unused in the program.
6595
6596Compiler
6597--------
6598- [The default allocator has changed from jemalloc to the default allocator on
6599 your system.][55238] The compiler itself on Linux & macOS will still use
6600 jemalloc, but programs compiled with it will use the system allocator.
6601- [Added the `aarch64-pc-windows-msvc` target.][55702]
6602
6603Libraries
6604---------
6605- [`PathBuf` now implements `FromStr`.][55148]
6606- [`Box<[T]>` now implements `FromIterator<T>`.][55843]
6607- [The `dbg!` macro has been stabilized.][56395] This macro enables you to
6608 easily debug expressions in your rust program. E.g.
6609 ```rust
6610 let a = 2;
6611 let b = dbg!(a * 2) + 1;
6612 // ^-- prints: [src/main.rs:4] a * 2 = 4
6613 assert_eq!(b, 5);
6614 ```
6615
6616The following APIs are now `const` functions and can be used in a
6617`const` context.
6618
6619- [`Cell::as_ptr`]
6620- [`UnsafeCell::get`]
6621- [`char::is_ascii`]
6622- [`iter::empty`]
6623- [`ManuallyDrop::new`]
6624- [`ManuallyDrop::into_inner`]
6625- [`RangeInclusive::start`]
6626- [`RangeInclusive::end`]
6627- [`NonNull::as_ptr`]
6628- [`slice::as_ptr`]
6629- [`str::as_ptr`]
6630- [`Duration::as_secs`]
6631- [`Duration::subsec_millis`]
6632- [`Duration::subsec_micros`]
6633- [`Duration::subsec_nanos`]
6634- [`CStr::as_ptr`]
6635- [`Ipv4Addr::is_unspecified`]
6636- [`Ipv6Addr::new`]
6637- [`Ipv6Addr::octets`]
6638
6639Stabilized APIs
6640---------------
6641- [`i8::to_be_bytes`]
6642- [`i8::to_le_bytes`]
6643- [`i8::to_ne_bytes`]
6644- [`i8::from_be_bytes`]
6645- [`i8::from_le_bytes`]
6646- [`i8::from_ne_bytes`]
6647- [`i16::to_be_bytes`]
6648- [`i16::to_le_bytes`]
6649- [`i16::to_ne_bytes`]
6650- [`i16::from_be_bytes`]
6651- [`i16::from_le_bytes`]
6652- [`i16::from_ne_bytes`]
6653- [`i32::to_be_bytes`]
6654- [`i32::to_le_bytes`]
6655- [`i32::to_ne_bytes`]
6656- [`i32::from_be_bytes`]
6657- [`i32::from_le_bytes`]
6658- [`i32::from_ne_bytes`]
6659- [`i64::to_be_bytes`]
6660- [`i64::to_le_bytes`]
6661- [`i64::to_ne_bytes`]
6662- [`i64::from_be_bytes`]
6663- [`i64::from_le_bytes`]
6664- [`i64::from_ne_bytes`]
6665- [`i128::to_be_bytes`]
6666- [`i128::to_le_bytes`]
6667- [`i128::to_ne_bytes`]
6668- [`i128::from_be_bytes`]
6669- [`i128::from_le_bytes`]
6670- [`i128::from_ne_bytes`]
6671- [`isize::to_be_bytes`]
6672- [`isize::to_le_bytes`]
6673- [`isize::to_ne_bytes`]
6674- [`isize::from_be_bytes`]
6675- [`isize::from_le_bytes`]
6676- [`isize::from_ne_bytes`]
6677- [`u8::to_be_bytes`]
6678- [`u8::to_le_bytes`]
6679- [`u8::to_ne_bytes`]
6680- [`u8::from_be_bytes`]
6681- [`u8::from_le_bytes`]
6682- [`u8::from_ne_bytes`]
6683- [`u16::to_be_bytes`]
6684- [`u16::to_le_bytes`]
6685- [`u16::to_ne_bytes`]
6686- [`u16::from_be_bytes`]
6687- [`u16::from_le_bytes`]
6688- [`u16::from_ne_bytes`]
6689- [`u32::to_be_bytes`]
6690- [`u32::to_le_bytes`]
6691- [`u32::to_ne_bytes`]
6692- [`u32::from_be_bytes`]
6693- [`u32::from_le_bytes`]
6694- [`u32::from_ne_bytes`]
6695- [`u64::to_be_bytes`]
6696- [`u64::to_le_bytes`]
6697- [`u64::to_ne_bytes`]
6698- [`u64::from_be_bytes`]
6699- [`u64::from_le_bytes`]
6700- [`u64::from_ne_bytes`]
6701- [`u128::to_be_bytes`]
6702- [`u128::to_le_bytes`]
6703- [`u128::to_ne_bytes`]
6704- [`u128::from_be_bytes`]
6705- [`u128::from_le_bytes`]
6706- [`u128::from_ne_bytes`]
6707- [`usize::to_be_bytes`]
6708- [`usize::to_le_bytes`]
6709- [`usize::to_ne_bytes`]
6710- [`usize::from_be_bytes`]
6711- [`usize::from_le_bytes`]
6712- [`usize::from_ne_bytes`]
6713
6714Cargo
6715-----
6716- [You can now run `cargo c` as an alias for `cargo check`.][cargo/6218]
6717- [Usernames are now allowed in alt registry URLs.][cargo/6242]
6718
6719Misc
6720----
6721- [`libproc_macro` has been added to the `rust-src` distribution.][55280]
6722
6723Compatibility Notes
6724-------------------
6725- [The argument types for AVX's
6726 `_mm256_stream_si256`, `_mm256_stream_pd`, `_mm256_stream_ps`][55610] have
6727 been changed from `*const` to `*mut` as the previous implementation
6728 was unsound.
6729
6730
6731[55148]: https://github.com/rust-lang/rust/pull/55148/
6732[55238]: https://github.com/rust-lang/rust/pull/55238/
6733[55280]: https://github.com/rust-lang/rust/pull/55280/
6734[55610]: https://github.com/rust-lang/rust/pull/55610/
6735[55663]: https://github.com/rust-lang/rust/pull/55663/
6736[55702]: https://github.com/rust-lang/rust/pull/55702/
6737[55837]: https://github.com/rust-lang/rust/pull/55837/
6738[55843]: https://github.com/rust-lang/rust/pull/55843/
6739[56072]: https://github.com/rust-lang/rust/pull/56072/
6740[56245]: https://github.com/rust-lang/rust/pull/56245/
6741[56365]: https://github.com/rust-lang/rust/pull/56365/
6742[56366]: https://github.com/rust-lang/rust/pull/56366/
6743[56395]: https://github.com/rust-lang/rust/pull/56395/
6744[56759]: https://github.com/rust-lang/rust/pull/56759/
6745[cargo/6218]: https://github.com/rust-lang/cargo/pull/6218/
6746[cargo/6242]: https://github.com/rust-lang/cargo/pull/6242/
6747[`CStr::as_ptr`]: https://doc.rust-lang.org/std/ffi/struct.CStr.html#method.as_ptr
6748[`Cell::as_ptr`]: https://doc.rust-lang.org/std/cell/struct.Cell.html#method.as_ptr
6749[`Duration::as_secs`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.as_secs
6750[`Duration::subsec_micros`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.subsec_micros
6751[`Duration::subsec_millis`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.subsec_millis
6752[`Duration::subsec_nanos`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.subsec_nanos
6753[`Ipv4Addr::is_unspecified`]: https://doc.rust-lang.org/std/net/struct.Ipv4Addr.html#method.is_unspecified
6754[`Ipv6Addr::new`]: https://doc.rust-lang.org/std/net/struct.Ipv6Addr.html#method.new
6755[`Ipv6Addr::octets`]: https://doc.rust-lang.org/std/net/struct.Ipv6Addr.html#method.octets
6756[`ManuallyDrop::into_inner`]: https://doc.rust-lang.org/std/mem/struct.ManuallyDrop.html#method.into_inner
6757[`ManuallyDrop::new`]: https://doc.rust-lang.org/std/mem/struct.ManuallyDrop.html#method.new
6758[`NonNull::as_ptr`]: https://doc.rust-lang.org/std/ptr/struct.NonNull.html#method.as_ptr
6759[`RangeInclusive::end`]: https://doc.rust-lang.org/std/ops/struct.RangeInclusive.html#method.end
6760[`RangeInclusive::start`]: https://doc.rust-lang.org/std/ops/struct.RangeInclusive.html#method.start
6761[`UnsafeCell::get`]: https://doc.rust-lang.org/std/cell/struct.UnsafeCell.html#method.get
6762[`slice::as_ptr`]: https://doc.rust-lang.org/std/primitive.slice.html#method.as_ptr
6763[`char::is_ascii`]: https://doc.rust-lang.org/std/primitive.char.html#method.is_ascii
6764[`i128::from_be_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i128.html#method.from_be_bytes
6765[`i128::from_le_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i128.html#method.from_le_bytes
6766[`i128::from_ne_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i128.html#method.from_ne_bytes
6767[`i128::to_be_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i128.html#method.to_be_bytes
6768[`i128::to_le_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i128.html#method.to_le_bytes
6769[`i128::to_ne_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i128.html#method.to_ne_bytes
6770[`i16::from_be_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i16.html#method.from_be_bytes
6771[`i16::from_le_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i16.html#method.from_le_bytes
6772[`i16::from_ne_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i16.html#method.from_ne_bytes
6773[`i16::to_be_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i16.html#method.to_be_bytes
6774[`i16::to_le_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i16.html#method.to_le_bytes
6775[`i16::to_ne_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i16.html#method.to_ne_bytes
6776[`i32::from_be_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i32.html#method.from_be_bytes
6777[`i32::from_le_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i32.html#method.from_le_bytes
6778[`i32::from_ne_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i32.html#method.from_ne_bytes
6779[`i32::to_be_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i32.html#method.to_be_bytes
6780[`i32::to_le_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i32.html#method.to_le_bytes
6781[`i32::to_ne_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i32.html#method.to_ne_bytes
6782[`i64::from_be_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i64.html#method.from_be_bytes
6783[`i64::from_le_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i64.html#method.from_le_bytes
6784[`i64::from_ne_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i64.html#method.from_ne_bytes
6785[`i64::to_be_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i64.html#method.to_be_bytes
6786[`i64::to_le_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i64.html#method.to_le_bytes
6787[`i64::to_ne_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i64.html#method.to_ne_bytes
6788[`i8::from_be_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i8.html#method.from_be_bytes
6789[`i8::from_le_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i8.html#method.from_le_bytes
6790[`i8::from_ne_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i8.html#method.from_ne_bytes
6791[`i8::to_be_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i8.html#method.to_be_bytes
6792[`i8::to_le_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i8.html#method.to_le_bytes
6793[`i8::to_ne_bytes`]: https://doc.rust-lang.org/stable/std/primitive.i8.html#method.to_ne_bytes
6794[`isize::from_be_bytes`]: https://doc.rust-lang.org/stable/std/primitive.isize.html#method.from_be_bytes
6795[`isize::from_le_bytes`]: https://doc.rust-lang.org/stable/std/primitive.isize.html#method.from_le_bytes
6796[`isize::from_ne_bytes`]: https://doc.rust-lang.org/stable/std/primitive.isize.html#method.from_ne_bytes
6797[`isize::to_be_bytes`]: https://doc.rust-lang.org/stable/std/primitive.isize.html#method.to_be_bytes
6798[`isize::to_le_bytes`]: https://doc.rust-lang.org/stable/std/primitive.isize.html#method.to_le_bytes
6799[`isize::to_ne_bytes`]: https://doc.rust-lang.org/stable/std/primitive.isize.html#method.to_ne_bytes
6800[`iter::empty`]: https://doc.rust-lang.org/std/iter/fn.empty.html
6801[`str::as_ptr`]: https://doc.rust-lang.org/std/primitive.str.html#method.as_ptr
6802[`u128::from_be_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u128.html#method.from_be_bytes
6803[`u128::from_le_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u128.html#method.from_le_bytes
6804[`u128::from_ne_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u128.html#method.from_ne_bytes
6805[`u128::to_be_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u128.html#method.to_be_bytes
6806[`u128::to_le_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u128.html#method.to_le_bytes
6807[`u128::to_ne_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u128.html#method.to_ne_bytes
6808[`u16::from_be_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u16.html#method.from_be_bytes
6809[`u16::from_le_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u16.html#method.from_le_bytes
6810[`u16::from_ne_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u16.html#method.from_ne_bytes
6811[`u16::to_be_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u16.html#method.to_be_bytes
6812[`u16::to_le_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u16.html#method.to_le_bytes
6813[`u16::to_ne_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u16.html#method.to_ne_bytes
6814[`u32::from_be_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u32.html#method.from_be_bytes
6815[`u32::from_le_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u32.html#method.from_le_bytes
6816[`u32::from_ne_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u32.html#method.from_ne_bytes
6817[`u32::to_be_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u32.html#method.to_be_bytes
6818[`u32::to_le_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u32.html#method.to_le_bytes
6819[`u32::to_ne_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u32.html#method.to_ne_bytes
6820[`u64::from_be_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u64.html#method.from_be_bytes
6821[`u64::from_le_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u64.html#method.from_le_bytes
6822[`u64::from_ne_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u64.html#method.from_ne_bytes
6823[`u64::to_be_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u64.html#method.to_be_bytes
6824[`u64::to_le_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u64.html#method.to_le_bytes
6825[`u64::to_ne_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u64.html#method.to_ne_bytes
6826[`u8::from_be_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u8.html#method.from_be_bytes
6827[`u8::from_le_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u8.html#method.from_le_bytes
6828[`u8::from_ne_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u8.html#method.from_ne_bytes
6829[`u8::to_be_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u8.html#method.to_be_bytes
6830[`u8::to_le_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u8.html#method.to_le_bytes
6831[`u8::to_ne_bytes`]: https://doc.rust-lang.org/stable/std/primitive.u8.html#method.to_ne_bytes
6832[`usize::from_be_bytes`]: https://doc.rust-lang.org/stable/std/primitive.usize.html#method.from_be_bytes
6833[`usize::from_le_bytes`]: https://doc.rust-lang.org/stable/std/primitive.usize.html#method.from_le_bytes
6834[`usize::from_ne_bytes`]: https://doc.rust-lang.org/stable/std/primitive.usize.html#method.from_ne_bytes
6835[`usize::to_be_bytes`]: https://doc.rust-lang.org/stable/std/primitive.usize.html#method.to_be_bytes
6836[`usize::to_le_bytes`]: https://doc.rust-lang.org/stable/std/primitive.usize.html#method.to_le_bytes
6837[`usize::to_ne_bytes`]: https://doc.rust-lang.org/stable/std/primitive.usize.html#method.to_ne_bytes
6838
6839
6840Version 1.31.1 (2018-12-20)
6841===========================
6842
6843- [Fix Rust failing to build on `powerpc-unknown-netbsd`][56562]
6844- [Fix broken go-to-definition in RLS][rls/1171]
6845- [Fix infinite loop on hover in RLS][rls/1170]
6846
6847[56562]: https://github.com/rust-lang/rust/pull/56562
6848[rls/1171]: https://github.com/rust-lang/rls/issues/1171
6849[rls/1170]: https://github.com/rust-lang/rls/pull/1170
6850
6851Version 1.31.0 (2018-12-06)
6852==========================
6853
6854Language
6855--------
6856- 🎉 [This version marks the release of the 2018 edition of Rust.][54057] 🎉
6857- [New lifetime elision rules now allow for eliding lifetimes in functions and
6858 impl headers.][54778] E.g. `impl<'a> Reader for BufReader<'a> {}` can now be
6859 `impl Reader for BufReader<'_> {}`. Lifetimes are still required to be defined
6860 in structs.
6861- [You can now define and use `const` functions.][54835] These are currently
6862 a strict minimal subset of the [const fn RFC][RFC-911]. Refer to the
6863 [language reference][const-reference] for what exactly is available.
6864- [You can now use tool lints, which allow you to scope lints from external
6865 tools using attributes.][54870] E.g. `#[allow(clippy::filter_map)]`.
6866- [`#[no_mangle]` and `#[export_name]` attributes can now be located anywhere in
6867 a crate, not just in exported functions.][54451]
6868- [You can now use parentheses in pattern matches.][54497]
6869
6870Compiler
6871--------
6872- [Updated musl to 1.1.20][54430]
6873
6874Libraries
6875---------
6876- [You can now convert `num::NonZero*` types to their raw equivalents using the
6877 `From` trait.][54240] E.g. `u8` now implements `From<NonZeroU8>`.
6878- [You can now convert a `&Option<T>` into `Option<&T>` and `&mut Option<T>`
6879 into `Option<&mut T>` using the `From` trait.][53218]
6880- [You can now multiply (`*`) a `time::Duration` by a `u32`.][52813]
6881
6882
6883Stabilized APIs
6884---------------
6885- [`slice::align_to`]
6886- [`slice::align_to_mut`]
6887- [`slice::chunks_exact`]
6888- [`slice::chunks_exact_mut`]
6889- [`slice::rchunks`]
6890- [`slice::rchunks_mut`]
6891- [`slice::rchunks_exact`]
6892- [`slice::rchunks_exact_mut`]
6893- [`Option::replace`]
6894
6895Cargo
6896-----
6897- [Cargo will now download crates in parallel using HTTP/2.][cargo/6005]
6898- [You can now rename packages in your Cargo.toml][cargo/6319] We have a guide
6899 on [how to use the `package` key in your dependencies.][cargo-rename-reference]
6900
6901[52813]: https://github.com/rust-lang/rust/pull/52813/
6902[53218]: https://github.com/rust-lang/rust/pull/53218/
6903[54057]: https://github.com/rust-lang/rust/pull/54057/
6904[54240]: https://github.com/rust-lang/rust/pull/54240/
6905[54430]: https://github.com/rust-lang/rust/pull/54430/
6906[54451]: https://github.com/rust-lang/rust/pull/54451/
6907[54497]: https://github.com/rust-lang/rust/pull/54497/
6908[54778]: https://github.com/rust-lang/rust/pull/54778/
6909[54835]: https://github.com/rust-lang/rust/pull/54835/
6910[54870]: https://github.com/rust-lang/rust/pull/54870/
6911[RFC-911]: https://github.com/rust-lang/rfcs/pull/911
6912[`Option::replace`]: https://doc.rust-lang.org/std/option/enum.Option.html#method.replace
6913[`slice::align_to_mut`]: https://doc.rust-lang.org/std/primitive.slice.html#method.align_to_mut
6914[`slice::align_to`]: https://doc.rust-lang.org/std/primitive.slice.html#method.align_to
6915[`slice::chunks_exact_mut`]: https://doc.rust-lang.org/std/primitive.slice.html#method.chunks_exact_mut
6916[`slice::chunks_exact`]: https://doc.rust-lang.org/std/primitive.slice.html#method.chunks_exact
6917[`slice::rchunks_exact_mut`]: https://doc.rust-lang.org/std/primitive.slice.html#method.rchunks_mut
6918[`slice::rchunks_exact`]: https://doc.rust-lang.org/std/primitive.slice.html#method.rchunks_exact
6919[`slice::rchunks_mut`]: https://doc.rust-lang.org/std/primitive.slice.html#method.rchunks_mut
6920[`slice::rchunks`]: https://doc.rust-lang.org/std/primitive.slice.html#method.rchunks
6921[cargo/6005]: https://github.com/rust-lang/cargo/pull/6005/
6922[cargo/6319]: https://github.com/rust-lang/cargo/pull/6319/
6923[cargo-rename-reference]: https://doc.rust-lang.org/cargo/reference/specifying-dependencies.html#renaming-dependencies-in-cargotoml
6924[const-reference]: https://doc.rust-lang.org/reference/items/functions.html#const-functions
6925
6926Version 1.30.1 (2018-11-08)
6927===========================
6928
6929- [Fixed overflow ICE in rustdoc][54199]
6930- [Cap Cargo progress bar width at 60 in MSYS terminals][cargo/6122]
6931
6932[54199]: https://github.com/rust-lang/rust/pull/54199
6933[cargo/6122]: https://github.com/rust-lang/cargo/pull/6122
6934
6935Version 1.30.0 (2018-10-25)
6936==========================
6937
6938Language
6939--------
6940- [Procedural macros are now available.][52081] These kinds of macros allow for
6941 more powerful code generation. There is a [new chapter available][proc-macros]
6942 in the Rust Programming Language book that goes further in depth.
6943- [You can now use keywords as identifiers using the raw identifiers
6944 syntax (`r#`),][53236] e.g. `let r#for = true;`
6945- [Using anonymous parameters in traits is now deprecated with a warning and
6946 will be a hard error in the 2018 edition.][53272]
6947- [You can now use `crate` in paths.][54404] This allows you to refer to the
6948 crate root in the path, e.g. `use crate::foo;` refers to `foo` in `src/lib.rs`.
6949- [Using a external crate no longer requires being prefixed with `::`.][54404]
6950 Previously, using a external crate in a module without a use statement
6951 required `let json = ::serde_json::from_str(foo);` but can now be written
6952 as `let json = serde_json::from_str(foo);`.
6953- [You can now apply the `#[used]` attribute to static items to prevent the
6954 compiler from optimising them away, even if they appear to be unused,][51363]
6955 e.g. `#[used] static FOO: u32 = 1;`
6956- [You can now import and reexport macros from other crates with the `use`
6957 syntax.][50911] Macros exported with `#[macro_export]` are now placed into
6958 the root module of the crate. If your macro relies on calling other local
6959 macros, it is recommended to export with the
6960 `#[macro_export(local_inner_macros)]` attribute so users won't have to import
6961 those macros.
6962- [You can now catch visibility keywords (e.g. `pub`, `pub(crate)`) in macros
6963 using the `vis` specifier.][53370]
6964- [Non-macro attributes now allow all forms of literals, not just
6965 strings.][53044] Previously, you would write `#[attr("true")]`, and you can now
6966 write `#[attr(true)]`.
6967- [You can now specify a function to handle a panic in the Rust runtime with the
6968 `#[panic_handler]` attribute.][51366]
6969
6970Compiler
6971--------
6972- [Added the `riscv32imc-unknown-none-elf` target.][53822]
6973- [Added the `aarch64-unknown-netbsd` target][53165]
6974- [Upgraded to LLVM 8.][53611]
6975
6976Libraries
6977---------
6978- [`ManuallyDrop` now allows the inner type to be unsized.][53033]
6979
6980Stabilized APIs
6981---------------
6982- [`Ipv4Addr::BROADCAST`]
6983- [`Ipv4Addr::LOCALHOST`]
6984- [`Ipv4Addr::UNSPECIFIED`]
6985- [`Ipv6Addr::LOCALHOST`]
6986- [`Ipv6Addr::UNSPECIFIED`]
6987- [`Iterator::find_map`]
6988
6989 The following methods are replacement methods for `trim_left`, `trim_right`,
6990 `trim_left_matches`, and `trim_right_matches`, which will be deprecated
6991 in 1.33.0:
6992- [`str::trim_end_matches`]
6993- [`str::trim_end`]
6994- [`str::trim_start_matches`]
6995- [`str::trim_start`]
6996
6997Cargo
6998----
6999- [`cargo run` doesn't require specifying a package in workspaces.][cargo/5877]
7000- [`cargo doc` now supports `--message-format=json`.][cargo/5878] This is
7001 equivalent to calling `rustdoc --error-format=json`.
7002- [Cargo will now provide a progress bar for builds.][cargo/5995]
7003
7004Misc
7005----
7006- [`rustdoc` allows you to specify what edition to treat your code as with the
7007 `--edition` option.][54057]
7008- [`rustdoc` now has the `--color` (specify whether to output color) and
7009 `--error-format` (specify error format, e.g. `json`) options.][53003]
7010- [We now distribute a `rust-gdbgui` script that invokes `gdbgui` with Rust
7011 debug symbols.][53774]
7012- [Attributes from Rust tools such as `rustfmt` or `clippy` are now
7013 available,][53459] e.g. `#[rustfmt::skip]` will skip formatting the next item.
7014
7015[50911]: https://github.com/rust-lang/rust/pull/50911/
7016[51363]: https://github.com/rust-lang/rust/pull/51363/
7017[51366]: https://github.com/rust-lang/rust/pull/51366/
7018[52081]: https://github.com/rust-lang/rust/pull/52081/
7019[53003]: https://github.com/rust-lang/rust/pull/53003/
7020[53033]: https://github.com/rust-lang/rust/pull/53033/
7021[53044]: https://github.com/rust-lang/rust/pull/53044/
7022[53165]: https://github.com/rust-lang/rust/pull/53165/
7023[53611]: https://github.com/rust-lang/rust/pull/53611/
7024[53236]: https://github.com/rust-lang/rust/pull/53236/
7025[53272]: https://github.com/rust-lang/rust/pull/53272/
7026[53370]: https://github.com/rust-lang/rust/pull/53370/
7027[53459]: https://github.com/rust-lang/rust/pull/53459/
7028[53774]: https://github.com/rust-lang/rust/pull/53774/
7029[53822]: https://github.com/rust-lang/rust/pull/53822/
7030[54057]: https://github.com/rust-lang/rust/pull/54057/
7031[54404]: https://github.com/rust-lang/rust/pull/54404/
7032[cargo/5877]: https://github.com/rust-lang/cargo/pull/5877/
7033[cargo/5878]: https://github.com/rust-lang/cargo/pull/5878/
7034[cargo/5995]: https://github.com/rust-lang/cargo/pull/5995/
7035[proc-macros]: https://doc.rust-lang.org/nightly/book/2018-edition/ch19-06-macros.html
7036
7037[`Ipv4Addr::BROADCAST`]: https://doc.rust-lang.org/nightly/std/net/struct.Ipv4Addr.html#associatedconstant.BROADCAST
7038[`Ipv4Addr::LOCALHOST`]: https://doc.rust-lang.org/nightly/std/net/struct.Ipv4Addr.html#associatedconstant.LOCALHOST
7039[`Ipv4Addr::UNSPECIFIED`]: https://doc.rust-lang.org/nightly/std/net/struct.Ipv4Addr.html#associatedconstant.UNSPECIFIED
7040[`Ipv6Addr::LOCALHOST`]: https://doc.rust-lang.org/nightly/std/net/struct.Ipv6Addr.html#associatedconstant.LOCALHOST
7041[`Ipv6Addr::UNSPECIFIED`]: https://doc.rust-lang.org/nightly/std/net/struct.Ipv6Addr.html#associatedconstant.UNSPECIFIED
7042[`Iterator::find_map`]: https://doc.rust-lang.org/std/iter/trait.Iterator.html#method.find_map
7043[`str::trim_end_matches`]: https://doc.rust-lang.org/nightly/std/primitive.str.html#method.trim_end_matches
7044[`str::trim_end`]: https://doc.rust-lang.org/nightly/std/primitive.str.html#method.trim_end
7045[`str::trim_start_matches`]: https://doc.rust-lang.org/nightly/std/primitive.str.html#method.trim_start_matches
7046[`str::trim_start`]: https://doc.rust-lang.org/nightly/std/primitive.str.html#method.trim_start
7047
7048
7049Version 1.29.2 (2018-10-11)
7050===========================
7051
7052- [Workaround for an aliasing-related LLVM bug, which caused miscompilation.][54639]
7053- The `rls-preview` component on the windows-gnu targets has been restored.
7054
7055[54639]: https://github.com/rust-lang/rust/pull/54639
7056
7057
7058Version 1.29.1 (2018-09-25)
7059===========================
7060
7061Security Notes
7062--------------
7063
7064- The standard library's `str::repeat` function contained an out of bounds write
7065 caused by an integer overflow. This has been fixed by deterministically
7066 panicking when an overflow happens.
7067
7068 Thank you to Scott McMurray for responsibly disclosing this vulnerability to
7069 us.
7070
7071
7072Version 1.29.0 (2018-09-13)
7073==========================
7074
7075Compiler
7076--------
7077- [Bumped minimum LLVM version to 5.0.][51899]
7078- [Added `powerpc64le-unknown-linux-musl` target.][51619]
7079- [Added `aarch64-unknown-hermit` and `x86_64-unknown-hermit` targets.][52861]
7080- [Upgraded to LLVM 7.][51966]
7081
7082Libraries
7083---------
7084- [`Once::call_once` no longer requires `Once` to be `'static`.][52239]
7085- [`BuildHasherDefault` now implements `PartialEq` and `Eq`.][52402]
7086- [`Box<CStr>`, `Box<OsStr>`, and `Box<Path>` now implement `Clone`.][51912]
7087- [Implemented `PartialEq<&str>` for `OsString` and `PartialEq<OsString>`
7088 for `&str`.][51178]
7089- [`Cell<T>` now allows `T` to be unsized.][50494]
7090- [`SocketAddr` is now stable on Redox.][52656]
7091
7092Stabilized APIs
7093---------------
7094- [`Arc::downcast`]
7095- [`Iterator::flatten`]
7096- [`Rc::downcast`]
7097
7098Cargo
7099-----
7100- [Cargo can silently fix some bad lockfiles.][cargo/5831] You can use
7101 `--locked` to disable this behavior.
7102- [`cargo-install` will now allow you to cross compile an install
7103 using `--target`.][cargo/5614]
7104- [Added the `cargo-fix` subcommand to automatically move project code from
7105 2015 edition to 2018.][cargo/5723]
7106- [`cargo doc` can now optionally document private types using the
7107 `--document-private-items` flag.][cargo/5543]
7108
7109Misc
7110----
7111- [`rustdoc` now has the `--cap-lints` option which demotes all lints above
7112 the specified level to that level.][52354] For example `--cap-lints warn`
7113 will demote `deny` and `forbid` lints to `warn`.
7114- [`rustc` and `rustdoc` will now have the exit code of `1` if compilation
7115 fails and `101` if there is a panic.][52197]
7116- [A preview of clippy has been made available through rustup.][51122]
7117 You can install the preview with `rustup component add clippy-preview`.
7118
7119Compatibility Notes
7120-------------------
7121- [`str::{slice_unchecked, slice_unchecked_mut}` are now deprecated.][51807]
7122 Use `str::get_unchecked(begin..end)` instead.
7123- [`std::env::home_dir` is now deprecated for its unintuitive behavior.][51656]
7124 Consider using the `home_dir` function from
7125 https://crates.io/crates/dirs instead.
7126- [`rustc` will no longer silently ignore invalid data in target spec.][52330]
7127- [`cfg` attributes and `--cfg` command line flags are now more
7128 strictly validated.][53893]
7129
7130[53893]: https://github.com/rust-lang/rust/pull/53893/
7131[52861]: https://github.com/rust-lang/rust/pull/52861/
7132[51966]: https://github.com/rust-lang/rust/pull/51966/
7133[52656]: https://github.com/rust-lang/rust/pull/52656/
7134[52239]: https://github.com/rust-lang/rust/pull/52239/
7135[52330]: https://github.com/rust-lang/rust/pull/52330/
7136[52354]: https://github.com/rust-lang/rust/pull/52354/
7137[52402]: https://github.com/rust-lang/rust/pull/52402/
7138[52197]: https://github.com/rust-lang/rust/pull/52197/
7139[51807]: https://github.com/rust-lang/rust/pull/51807/
7140[51899]: https://github.com/rust-lang/rust/pull/51899/
7141[51912]: https://github.com/rust-lang/rust/pull/51912/
7142[51619]: https://github.com/rust-lang/rust/pull/51619/
7143[51656]: https://github.com/rust-lang/rust/pull/51656/
7144[51178]: https://github.com/rust-lang/rust/pull/51178/
7145[51122]: https://github.com/rust-lang/rust/pull/51122
7146[50494]: https://github.com/rust-lang/rust/pull/50494/
7147[cargo/5543]: https://github.com/rust-lang/cargo/pull/5543
7148[cargo/5614]: https://github.com/rust-lang/cargo/pull/5614/
7149[cargo/5723]: https://github.com/rust-lang/cargo/pull/5723/
7150[cargo/5831]: https://github.com/rust-lang/cargo/pull/5831/
7151[`Arc::downcast`]: https://doc.rust-lang.org/std/sync/struct.Arc.html#method.downcast
7152[`Iterator::flatten`]: https://doc.rust-lang.org/std/iter/trait.Iterator.html#method.flatten
7153[`Rc::downcast`]: https://doc.rust-lang.org/std/rc/struct.Rc.html#method.downcast
7154
7155
7156Version 1.28.0 (2018-08-02)
7157===========================
7158
7159Language
7160--------
7161- [The `#[repr(transparent)]` attribute is now stable.][51562] This attribute
7162 allows a Rust newtype wrapper (`struct NewType<T>(T);`) to be represented as
7163 the inner type across Foreign Function Interface (FFI) boundaries.
7164- [The keywords `pure`, `sizeof`, `alignof`, and `offsetof` have been unreserved
7165 and can now be used as identifiers.][51196]
7166- [The `GlobalAlloc` trait and `#[global_allocator]` attribute are now
7167 stable.][51241] This will allow users to specify a global allocator for
7168 their program.
7169- [Unit test functions marked with the `#[test]` attribute can now return
7170 `Result<(), E: Debug>` in addition to `()`.][51298]
7171- [The `lifetime` specifier for `macro_rules!` is now stable.][50385] This
7172 allows macros to easily target lifetimes.
7173
7174Compiler
7175--------
7176- [The `s` and `z` optimisation levels are now stable.][50265] These optimisations
7177 prioritise making smaller binary sizes. `z` is the same as `s` with the
7178 exception that it does not vectorise loops, which typically results in an even
7179 smaller binary.
7180- [The short error format is now stable.][49546] Specified with
7181 `--error-format=short` this option will provide a more compressed output of
7182 rust error messages.
7183- [Added a lint warning when you have duplicated `macro_export`s.][50143]
7184- [Reduced the number of allocations in the macro parser.][50855] This can
7185 improve compile times of macro heavy crates on average by 5%.
7186
7187Libraries
7188---------
7189- [Implemented `Default` for `&mut str`.][51306]
7190- [Implemented `From<bool>` for all integer and unsigned number types.][50554]
7191- [Implemented `Extend` for `()`.][50234]
7192- [The `Debug` implementation of `time::Duration` should now be more easily
7193 human readable.][50364] Previously a `Duration` of one second would printed as
7194 `Duration { secs: 1, nanos: 0 }` and will now be printed as `1s`.
7195- [Implemented `From<&String>` for `Cow<str>`, `From<&Vec<T>>` for `Cow<[T]>`,
7196 `From<Cow<CStr>>` for `CString`, `From<CString>, From<CStr>, From<&CString>`
7197 for `Cow<CStr>`, `From<OsString>, From<OsStr>, From<&OsString>` for
7198 `Cow<OsStr>`, `From<&PathBuf>` for `Cow<Path>`, and `From<Cow<Path>>`
7199 for `PathBuf`.][50170]
7200- [Implemented `Shl` and `Shr` for `Wrapping<u128>`
7201 and `Wrapping<i128>`.][50465]
7202- [`DirEntry::metadata` now uses `fstatat` instead of `lstat` when
7203 possible.][51050] This can provide up to a 40% speed increase.
7204- [Improved error messages when using `format!`.][50610]
7205
7206Stabilized APIs
7207---------------
7208- [`Iterator::step_by`]
7209- [`Path::ancestors`]
7210- [`SystemTime::UNIX_EPOCH`]
7211- [`alloc::GlobalAlloc`]
7212- [`alloc::Layout`]
7213- [`alloc::LayoutErr`]
7214- [`alloc::System`]
7215- [`alloc::alloc`]
7216- [`alloc::alloc_zeroed`]
7217- [`alloc::dealloc`]
7218- [`alloc::realloc`]
7219- [`alloc::handle_alloc_error`]
7220- [`btree_map::Entry::or_default`]
7221- [`fmt::Alignment`]
7222- [`hash_map::Entry::or_default`]
7223- [`iter::repeat_with`]
7224- [`num::NonZeroUsize`]
7225- [`num::NonZeroU128`]
7226- [`num::NonZeroU16`]
7227- [`num::NonZeroU32`]
7228- [`num::NonZeroU64`]
7229- [`num::NonZeroU8`]
7230- [`ops::RangeBounds`]
7231- [`slice::SliceIndex`]
7232- [`slice::from_mut`]
7233- [`slice::from_ref`]
7234- [`{Any + Send + Sync}::downcast_mut`]
7235- [`{Any + Send + Sync}::downcast_ref`]
7236- [`{Any + Send + Sync}::is`]
7237
7238Cargo
7239-----
7240- [Cargo will now no longer allow you to publish crates with build scripts that
7241 modify the `src` directory.][cargo/5584] The `src` directory in a crate should be
7242 considered to be immutable.
7243
7244Misc
7245----
7246- [The `suggestion_applicability` field in `rustc`'s json output is now
7247 stable.][50486] This will allow dev tools to check whether a code suggestion
7248 would apply to them.
7249
7250Compatibility Notes
7251-------------------
7252- [Rust will consider trait objects with duplicated constraints to be the same
7253 type as without the duplicated constraint.][51276] For example the below code will
7254 now fail to compile.
7255 ```rust
7256 trait Trait {}
7257
7258 impl Trait + Send {
7259 fn test(&self) { println!("one"); } //~ ERROR duplicate definitions with name `test`
7260 }
7261
7262 impl Trait + Send + Send {
7263 fn test(&self) { println!("two"); }
7264 }
7265 ```
7266
7267[49546]: https://github.com/rust-lang/rust/pull/49546/
7268[50143]: https://github.com/rust-lang/rust/pull/50143/
7269[50170]: https://github.com/rust-lang/rust/pull/50170/
7270[50234]: https://github.com/rust-lang/rust/pull/50234/
7271[50265]: https://github.com/rust-lang/rust/pull/50265/
7272[50364]: https://github.com/rust-lang/rust/pull/50364/
7273[50385]: https://github.com/rust-lang/rust/pull/50385/
7274[50465]: https://github.com/rust-lang/rust/pull/50465/
7275[50486]: https://github.com/rust-lang/rust/pull/50486/
7276[50554]: https://github.com/rust-lang/rust/pull/50554/
7277[50610]: https://github.com/rust-lang/rust/pull/50610/
7278[50855]: https://github.com/rust-lang/rust/pull/50855/
7279[51050]: https://github.com/rust-lang/rust/pull/51050/
7280[51196]: https://github.com/rust-lang/rust/pull/51196/
7281[51241]: https://github.com/rust-lang/rust/pull/51241/
7282[51276]: https://github.com/rust-lang/rust/pull/51276/
7283[51298]: https://github.com/rust-lang/rust/pull/51298/
7284[51306]: https://github.com/rust-lang/rust/pull/51306/
7285[51562]: https://github.com/rust-lang/rust/pull/51562/
7286[cargo/5584]: https://github.com/rust-lang/cargo/pull/5584/
7287[`Iterator::step_by`]: https://doc.rust-lang.org/std/iter/trait.Iterator.html#method.step_by
7288[`Path::ancestors`]: https://doc.rust-lang.org/std/path/struct.Path.html#method.ancestors
7289[`SystemTime::UNIX_EPOCH`]: https://doc.rust-lang.org/std/time/struct.SystemTime.html#associatedconstant.UNIX_EPOCH
7290[`alloc::GlobalAlloc`]: https://doc.rust-lang.org/std/alloc/trait.GlobalAlloc.html
7291[`alloc::Layout`]: https://doc.rust-lang.org/std/alloc/struct.Layout.html
7292[`alloc::LayoutErr`]: https://doc.rust-lang.org/std/alloc/struct.LayoutErr.html
7293[`alloc::System`]: https://doc.rust-lang.org/std/alloc/struct.System.html
7294[`alloc::alloc`]: https://doc.rust-lang.org/std/alloc/fn.alloc.html
7295[`alloc::alloc_zeroed`]: https://doc.rust-lang.org/std/alloc/fn.alloc_zeroed.html
7296[`alloc::dealloc`]: https://doc.rust-lang.org/std/alloc/fn.dealloc.html
7297[`alloc::realloc`]: https://doc.rust-lang.org/std/alloc/fn.realloc.html
7298[`alloc::handle_alloc_error`]: https://doc.rust-lang.org/std/alloc/fn.handle_alloc_error.html
7299[`btree_map::Entry::or_default`]: https://doc.rust-lang.org/std/collections/btree_map/enum.Entry.html#method.or_default
7300[`fmt::Alignment`]: https://doc.rust-lang.org/std/fmt/enum.Alignment.html
7301[`hash_map::Entry::or_default`]: https://doc.rust-lang.org/std/collections/hash_map/enum.Entry.html#method.or_default
7302[`iter::repeat_with`]: https://doc.rust-lang.org/std/iter/fn.repeat_with.html
7303[`num::NonZeroUsize`]: https://doc.rust-lang.org/std/num/struct.NonZeroUsize.html
7304[`num::NonZeroU128`]: https://doc.rust-lang.org/std/num/struct.NonZeroU128.html
7305[`num::NonZeroU16`]: https://doc.rust-lang.org/std/num/struct.NonZeroU16.html
7306[`num::NonZeroU32`]: https://doc.rust-lang.org/std/num/struct.NonZeroU32.html
7307[`num::NonZeroU64`]: https://doc.rust-lang.org/std/num/struct.NonZeroU64.html
7308[`num::NonZeroU8`]: https://doc.rust-lang.org/std/num/struct.NonZeroU8.html
7309[`ops::RangeBounds`]: https://doc.rust-lang.org/std/ops/trait.RangeBounds.html
7310[`slice::SliceIndex`]: https://doc.rust-lang.org/std/slice/trait.SliceIndex.html
7311[`slice::from_mut`]: https://doc.rust-lang.org/std/slice/fn.from_mut.html
7312[`slice::from_ref`]: https://doc.rust-lang.org/std/slice/fn.from_ref.html
7313[`{Any + Send + Sync}::downcast_mut`]: https://doc.rust-lang.org/std/any/trait.Any.html#method.downcast_mut-2
7314[`{Any + Send + Sync}::downcast_ref`]: https://doc.rust-lang.org/std/any/trait.Any.html#method.downcast_ref-2
7315[`{Any + Send + Sync}::is`]: https://doc.rust-lang.org/std/any/trait.Any.html#method.is-2
7316
7317Version 1.27.2 (2018-07-20)
7318===========================
7319
7320Compatibility Notes
7321-------------------
7322
7323- The borrow checker was fixed to avoid potential unsoundness when using
7324 match ergonomics: [#52213][52213].
7325
7326[52213]: https://github.com/rust-lang/rust/issues/52213
7327
7328Version 1.27.1 (2018-07-10)
7329===========================
7330
7331Security Notes
7332--------------
7333
7334- rustdoc would execute plugins in the /tmp/rustdoc/plugins directory
7335 when running, which enabled executing code as some other user on a
7336 given machine. This release fixes that vulnerability; you can read
7337 more about this on the [blog][rustdoc-sec]. The associated CVE is [CVE-2018-1000622].
7338
7339 Thank you to Red Hat for responsibly disclosing this vulnerability to us.
7340
7341Compatibility Notes
7342-------------------
7343
7344- The borrow checker was fixed to avoid an additional potential unsoundness when using
7345 match ergonomics: [#51415][51415], [#49534][49534].
7346
7347[51415]: https://github.com/rust-lang/rust/issues/51415
7348[49534]: https://github.com/rust-lang/rust/issues/49534
7349[rustdoc-sec]: https://blog.rust-lang.org/2018/07/06/security-advisory-for-rustdoc.html
7350[CVE-2018-1000622]: https://cve.mitre.org/cgi-bin/cvename.cgi?name=%20CVE-2018-1000622
7351
7352Version 1.27.0 (2018-06-21)
7353==========================
7354
7355Language
7356--------
7357- [Removed 'proc' from the reserved keywords list.][49699] This allows `proc` to
7358 be used as an identifier.
7359- [The dyn syntax is now available.][49968] This syntax is equivalent to the
7360 bare `Trait` syntax, and should make it clearer when being used in tandem with
7361 `impl Trait` because it is equivalent to the following syntax:
7362 `&Trait == &dyn Trait`, `&mut Trait == &mut dyn Trait`, and
7363 `Box<Trait> == Box<dyn Trait>`.
7364- [Attributes on generic parameters such as types and lifetimes are
7365 now stable.][48851] e.g.
7366 `fn foo<#[lifetime_attr] 'a, #[type_attr] T: 'a>() {}`
7367- [The `#[must_use]` attribute can now also be used on functions as well as
7368 types.][48925] It provides a lint that by default warns users when the
7369 value returned by a function has not been used.
7370
7371Compiler
7372--------
7373- [Added the `armv5te-unknown-linux-musleabi` target.][50423]
7374
7375Libraries
7376---------
7377- [SIMD (Single Instruction Multiple Data) on x86/x86_64 is now stable.][49664]
7378 This includes [`arch::x86`] & [`arch::x86_64`] modules which contain
7379 SIMD intrinsics, a new macro called `is_x86_feature_detected!`, the
7380 `#[target_feature(enable="")]` attribute, and adding `target_feature = ""` to
7381 the `cfg` attribute.
7382- [A lot of methods for `[u8]`, `f32`, and `f64` previously only available in
7383 std are now available in core.][49896]
7384- [The generic `Rhs` type parameter on `ops::{Shl, ShlAssign, Shr}` now defaults
7385 to `Self`.][49630]
7386- [`std::str::replace` now has the `#[must_use]` attribute][50177] to clarify
7387 that the operation isn't done in place.
7388- [`Clone::clone`, `Iterator::collect`, and `ToOwned::to_owned` now have
7389 the `#[must_use]` attribute][49533] to warn about unused potentially
7390 expensive allocations.
7391
7392Stabilized APIs
7393---------------
7394- [`DoubleEndedIterator::rfind`]
7395- [`DoubleEndedIterator::rfold`]
7396- [`DoubleEndedIterator::try_rfold`]
7397- [`Duration::from_micros`]
7398- [`Duration::from_nanos`]
7399- [`Duration::subsec_micros`]
7400- [`Duration::subsec_millis`]
7401- [`HashMap::remove_entry`]
7402- [`Iterator::try_fold`]
7403- [`Iterator::try_for_each`]
7404- [`NonNull::cast`]
7405- [`Option::filter`]
7406- [`String::replace_range`]
7407- [`Take::set_limit`]
7408- [`hint::unreachable_unchecked`]
7409- [`os::unix::process::parent_id`]
7410- [`ptr::swap_nonoverlapping`]
7411- [`slice::rsplit_mut`]
7412- [`slice::rsplit`]
7413- [`slice::swap_with_slice`]
7414
7415Cargo
7416-----
7417- [`cargo-metadata` now includes `authors`, `categories`, `keywords`,
7418 `readme`, and `repository` fields.][cargo/5386]
7419- [`cargo-metadata` now includes a package's `metadata` table.][cargo/5360]
7420- [Added the `--target-dir` optional argument.][cargo/5393] This allows you to specify
7421 a different directory than `target` for placing compilation artifacts.
7422- [Cargo will be adding automatic target inference for binaries, benchmarks,
7423 examples, and tests in the Rust 2018 edition.][cargo/5335] If your project specifies
7424 specific targets, e.g. using `[[bin]]`, and have other binaries in locations
7425 where cargo would infer a binary, Cargo will produce a warning. You can
7426 disable this feature ahead of time by setting any of the following to false:
7427 `autobins`, `autobenches`, `autoexamples`, `autotests`.
7428- [Cargo will now cache compiler information.][cargo/5359] This can be disabled by
7429 setting `CARGO_CACHE_RUSTC_INFO=0` in your environment.
7430
7431Misc
7432----
7433- [Added “The Rustc book” into the official documentation.][49707]
7434 [“The Rustc book”] documents and teaches how to use the rustc compiler.
7435- [All books available on `doc.rust-lang.org` are now searchable.][49623]
7436
7437Compatibility Notes
7438-------------------
7439- [Calling a `CharExt` or `StrExt` method directly on core will no longer
7440 work.][49896] e.g. `::core::prelude::v1::StrExt::is_empty("")` will not
7441 compile, `"".is_empty()` will still compile.
7442- [`Debug` output on `atomic::{AtomicBool, AtomicIsize, AtomicPtr, AtomicUsize}`
7443 will only print the inner type.][48553] E.g.
7444 `print!("{:?}", AtomicBool::new(true))` will print `true`,
7445 not `AtomicBool(true)`.
7446- [The maximum number for `repr(align(N))` is now 2²⁹.][50378] Previously you
7447 could enter higher numbers but they were not supported by LLVM. Up to 512MB
7448 alignment should cover all use cases.
7449- The `.description()` method on the `std::error::Error` trait
7450 [has been soft-deprecated][50163]. It is no longer required to implement it.
7451
7452[48553]: https://github.com/rust-lang/rust/pull/48553/
7453[48851]: https://github.com/rust-lang/rust/pull/48851/
7454[48925]: https://github.com/rust-lang/rust/pull/48925/
7455[49533]: https://github.com/rust-lang/rust/pull/49533/
7456[49623]: https://github.com/rust-lang/rust/pull/49623/
7457[49630]: https://github.com/rust-lang/rust/pull/49630/
7458[49664]: https://github.com/rust-lang/rust/pull/49664/
7459[49699]: https://github.com/rust-lang/rust/pull/49699/
7460[49707]: https://github.com/rust-lang/rust/pull/49707/
7461[49896]: https://github.com/rust-lang/rust/pull/49896/
7462[49968]: https://github.com/rust-lang/rust/pull/49968/
7463[50163]: https://github.com/rust-lang/rust/pull/50163
7464[50177]: https://github.com/rust-lang/rust/pull/50177/
7465[50378]: https://github.com/rust-lang/rust/pull/50378/
7466[50423]: https://github.com/rust-lang/rust/pull/50423/
7467[cargo/5335]: https://github.com/rust-lang/cargo/pull/5335/
7468[cargo/5359]: https://github.com/rust-lang/cargo/pull/5359/
7469[cargo/5360]: https://github.com/rust-lang/cargo/pull/5360/
7470[cargo/5386]: https://github.com/rust-lang/cargo/pull/5386/
7471[cargo/5393]: https://github.com/rust-lang/cargo/pull/5393/
7472[`DoubleEndedIterator::rfind`]: https://doc.rust-lang.org/std/iter/trait.DoubleEndedIterator.html#method.rfind
7473[`DoubleEndedIterator::rfold`]: https://doc.rust-lang.org/std/iter/trait.DoubleEndedIterator.html#method.rfold
7474[`DoubleEndedIterator::try_rfold`]: https://doc.rust-lang.org/std/iter/trait.DoubleEndedIterator.html#method.try_rfold
7475[`Duration::from_micros`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.from_micros
7476[`Duration::from_nanos`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.from_nanos
7477[`Duration::subsec_micros`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.subsec_micros
7478[`Duration::subsec_millis`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.subsec_millis
7479[`HashMap::remove_entry`]: https://doc.rust-lang.org/std/collections/struct.HashMap.html#method.remove_entry
7480[`Iterator::try_fold`]: https://doc.rust-lang.org/std/iter/trait.Iterator.html#method.try_fold
7481[`Iterator::try_for_each`]: https://doc.rust-lang.org/std/iter/trait.Iterator.html#method.try_for_each
7482[`NonNull::cast`]: https://doc.rust-lang.org/std/ptr/struct.NonNull.html#method.cast
7483[`Option::filter`]: https://doc.rust-lang.org/std/option/enum.Option.html#method.filter
7484[`String::replace_range`]: https://doc.rust-lang.org/std/string/struct.String.html#method.replace_range
7485[`Take::set_limit`]: https://doc.rust-lang.org/std/io/struct.Take.html#method.set_limit
7486[`hint::unreachable_unchecked`]: https://doc.rust-lang.org/std/hint/fn.unreachable_unchecked.html
7487[`os::unix::process::parent_id`]: https://doc.rust-lang.org/std/os/unix/process/fn.parent_id.html
7488[`process::id`]: https://doc.rust-lang.org/std/process/fn.id.html
7489[`ptr::swap_nonoverlapping`]: https://doc.rust-lang.org/std/ptr/fn.swap_nonoverlapping.html
7490[`slice::rsplit_mut`]: https://doc.rust-lang.org/std/primitive.slice.html#method.rsplit_mut
7491[`slice::rsplit`]: https://doc.rust-lang.org/std/primitive.slice.html#method.rsplit
7492[`slice::swap_with_slice`]: https://doc.rust-lang.org/std/primitive.slice.html#method.swap_with_slice
7493[`arch::x86_64`]: https://doc.rust-lang.org/std/arch/x86_64/index.html
7494[`arch::x86`]: https://doc.rust-lang.org/std/arch/x86/index.html
7495[“The Rustc book”]: https://doc.rust-lang.org/rustc
7496
7497
7498Version 1.26.2 (2018-06-05)
7499==========================
7500
7501Compatibility Notes
7502-------------------
7503
7504- [The borrow checker was fixed to avoid unsoundness when using match ergonomics.][51117]
7505
7506[51117]: https://github.com/rust-lang/rust/issues/51117
7507
7508
7509Version 1.26.1 (2018-05-29)
7510==========================
7511
7512Tools
7513-----
7514
7515- [RLS now works on Windows.][50646]
7516- [Rustfmt stopped badly formatting text in some cases.][rustfmt/2695]
7517
7518
7519Compatibility Notes
7520--------
7521
7522- [`fn main() -> impl Trait` no longer works for non-Termination
7523 trait.][50656]
7524 This reverts an accidental stabilization.
7525- [`NaN > NaN` no longer returns true in const-fn contexts.][50812]
7526- [Prohibit using turbofish for `impl Trait` in method arguments.][50950]
7527
7528[50646]: https://github.com/rust-lang/rust/issues/50646
7529[50656]: https://github.com/rust-lang/rust/pull/50656
7530[50812]: https://github.com/rust-lang/rust/pull/50812
7531[50950]: https://github.com/rust-lang/rust/issues/50950
7532[rustfmt/2695]: https://github.com/rust-lang-nursery/rustfmt/issues/2695
7533
7534Version 1.26.0 (2018-05-10)
7535==========================
7536
7537Language
7538--------
7539- [Closures now implement `Copy` and/or `Clone` if all captured variables
7540 implement either or both traits.][49299]
7541- [The inclusive range syntax e.g. `for x in 0..=10` is now stable.][47813]
7542- [The `'_` lifetime is now stable. The underscore lifetime can be used anywhere a
7543 lifetime can be elided.][49458]
7544- [`impl Trait` is now stable allowing you to have abstract types in returns
7545 or in function parameters.][49255] E.g. `fn foo() -> impl Iterator<Item=u8>` or
7546 `fn open(path: impl AsRef<Path>)`.
7547- [Pattern matching will now automatically apply dereferences.][49394]
7548- [128-bit integers in the form of `u128` and `i128` are now stable.][49101]
7549- [`main` can now return `Result<(), E: Debug>`][49162] in addition to `()`.
7550- [A lot of operations are now available in a const context.][46882] E.g. You
7551 can now index into constant arrays, reference and dereference into constants,
7552 and use tuple struct constructors.
7553- [Fixed entry slice patterns are now stable.][48516] E.g.
7554 ```rust
7555 let points = [1, 2, 3, 4];
7556 match points {
7557 [1, 2, 3, 4] => println!("All points were sequential."),
7558 _ => println!("Not all points were sequential."),
7559 }
7560 ```
7561
7562
7563Compiler
7564--------
7565- [LLD is now used as the default linker for `wasm32-unknown-unknown`.][48125]
7566- [Fixed exponential projection complexity on nested types.][48296]
7567 This can provide up to a ~12% reduction in compile times for certain crates.
7568- [Added the `--remap-path-prefix` option to rustc.][48359] Allowing you
7569 to remap path prefixes outputted by the compiler.
7570- [Added `powerpc-unknown-netbsd` target.][48281]
7571
7572Libraries
7573---------
7574- [Implemented `From<u16> for usize` & `From<{u8, i16}> for isize`.][49305]
7575- [Added hexadecimal formatting for integers with fmt::Debug][48978]
7576 e.g. `assert!(format!("{:02x?}", b"Foo\0") == "[46, 6f, 6f, 00]")`
7577- [Implemented `Default, Hash` for `cmp::Reverse`.][48628]
7578- [Optimized `str::repeat` being 8x faster in large cases.][48657]
7579- [`ascii::escape_default` is now available in libcore.][48735]
7580- [Trailing commas are now supported in std and core macros.][48056]
7581- [Implemented `Copy, Clone` for `cmp::Reverse`][47379]
7582- [Implemented `Clone` for `char::{ToLowercase, ToUppercase}`.][48629]
7583
7584Stabilized APIs
7585---------------
7586- [`*const T::add`]
7587- [`*const T::copy_to_nonoverlapping`]
7588- [`*const T::copy_to`]
7589- [`*const T::read_unaligned`]
7590- [`*const T::read_volatile`]
7591- [`*const T::read`]
7592- [`*const T::sub`]
7593- [`*const T::wrapping_add`]
7594- [`*const T::wrapping_sub`]
7595- [`*mut T::add`]
7596- [`*mut T::copy_to_nonoverlapping`]
7597- [`*mut T::copy_to`]
7598- [`*mut T::read_unaligned`]
7599- [`*mut T::read_volatile`]
7600- [`*mut T::read`]
7601- [`*mut T::replace`]
7602- [`*mut T::sub`]
7603- [`*mut T::swap`]
7604- [`*mut T::wrapping_add`]
7605- [`*mut T::wrapping_sub`]
7606- [`*mut T::write_bytes`]
7607- [`*mut T::write_unaligned`]
7608- [`*mut T::write_volatile`]
7609- [`*mut T::write`]
7610- [`Box::leak`]
7611- [`FromUtf8Error::as_bytes`]
7612- [`LocalKey::try_with`]
7613- [`Option::cloned`]
7614- [`btree_map::Entry::and_modify`]
7615- [`fs::read_to_string`]
7616- [`fs::read`]
7617- [`fs::write`]
7618- [`hash_map::Entry::and_modify`]
7619- [`iter::FusedIterator`]
7620- [`ops::RangeInclusive`]
7621- [`ops::RangeToInclusive`]
7622- [`process::id`]
7623- [`slice::rotate_left`]
7624- [`slice::rotate_right`]
7625- [`String::retain`]
7626
7627
7628Cargo
7629-----
7630- [Cargo will now output path to custom commands when `-v` is
7631 passed with `--list`][cargo/5041]
7632- [The Cargo binary version is now the same as the Rust version][cargo/5083]
7633
7634Misc
7635----
7636- [The second edition of "The Rust Programming Language" book is now recommended
7637 over the first.][48404]
7638
7639Compatibility Notes
7640-------------------
7641
7642- [aliasing a `Fn` trait as `dyn` no longer works.][48481] E.g. the following
7643 syntax is now invalid.
7644 ```
7645 use std::ops::Fn as dyn;
7646 fn g(_: Box<dyn(std::fmt::Debug)>) {}
7647 ```
7648- [The result of dereferences are no longer promoted to `'static`.][47408]
7649 e.g.
7650 ```rust
7651 fn main() {
7652 const PAIR: &(i32, i32) = &(0, 1);
7653 let _reversed_pair: &'static _ = &(PAIR.1, PAIR.0); // Doesn't work
7654 }
7655 ```
7656- [Deprecate `AsciiExt` trait in favor of inherent methods.][49109]
7657- [`".e0"` will now no longer parse as `0.0` and will instead cause
7658 an error.][48235]
7659- [Removed hoedown from rustdoc.][48274]
7660- [Bounds on higher-kinded lifetimes a hard error.][48326]
7661
7662[46882]: https://github.com/rust-lang/rust/pull/46882
7663[47379]: https://github.com/rust-lang/rust/pull/47379
7664[47408]: https://github.com/rust-lang/rust/pull/47408
7665[47813]: https://github.com/rust-lang/rust/pull/47813
7666[48056]: https://github.com/rust-lang/rust/pull/48056
7667[48125]: https://github.com/rust-lang/rust/pull/48125
7668[48235]: https://github.com/rust-lang/rust/pull/48235
7669[48274]: https://github.com/rust-lang/rust/pull/48274
7670[48281]: https://github.com/rust-lang/rust/pull/48281
7671[48296]: https://github.com/rust-lang/rust/pull/48296
7672[48326]: https://github.com/rust-lang/rust/pull/48326
7673[48359]: https://github.com/rust-lang/rust/pull/48359
7674[48404]: https://github.com/rust-lang/rust/pull/48404
7675[48481]: https://github.com/rust-lang/rust/pull/48481
7676[48516]: https://github.com/rust-lang/rust/pull/48516
7677[48628]: https://github.com/rust-lang/rust/pull/48628
7678[48629]: https://github.com/rust-lang/rust/pull/48629
7679[48657]: https://github.com/rust-lang/rust/pull/48657
7680[48735]: https://github.com/rust-lang/rust/pull/48735
7681[48978]: https://github.com/rust-lang/rust/pull/48978
7682[49101]: https://github.com/rust-lang/rust/pull/49101
7683[49109]: https://github.com/rust-lang/rust/pull/49109
7684[49162]: https://github.com/rust-lang/rust/pull/49162
7685[49255]: https://github.com/rust-lang/rust/pull/49255
7686[49299]: https://github.com/rust-lang/rust/pull/49299
7687[49305]: https://github.com/rust-lang/rust/pull/49305
7688[49394]: https://github.com/rust-lang/rust/pull/49394
7689[49458]: https://github.com/rust-lang/rust/pull/49458
7690[`*const T::add`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.add
7691[`*const T::copy_to_nonoverlapping`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.copy_to_nonoverlapping
7692[`*const T::copy_to`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.copy_to
7693[`*const T::read_unaligned`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.read_unaligned
7694[`*const T::read_volatile`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.read_volatile
7695[`*const T::read`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.read
7696[`*const T::sub`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.sub
7697[`*const T::wrapping_add`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.wrapping_add
7698[`*const T::wrapping_sub`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.wrapping_sub
7699[`*mut T::add`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.add-1
7700[`*mut T::copy_to_nonoverlapping`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.copy_to_nonoverlapping-1
7701[`*mut T::copy_to`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.copy_to-1
7702[`*mut T::read_unaligned`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.read_unaligned-1
7703[`*mut T::read_volatile`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.read_volatile-1
7704[`*mut T::read`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.read-1
7705[`*mut T::replace`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.replace
7706[`*mut T::sub`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.sub-1
7707[`*mut T::swap`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.swap
7708[`*mut T::wrapping_add`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.wrapping_add-1
7709[`*mut T::wrapping_sub`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.wrapping_sub-1
7710[`*mut T::write_bytes`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.write_bytes
7711[`*mut T::write_unaligned`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.write_unaligned
7712[`*mut T::write_volatile`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.write_volatile
7713[`*mut T::write`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.write
7714[`Box::leak`]: https://doc.rust-lang.org/std/boxed/struct.Box.html#method.leak
7715[`FromUtf8Error::as_bytes`]: https://doc.rust-lang.org/std/string/struct.FromUtf8Error.html#method.as_bytes
7716[`LocalKey::try_with`]: https://doc.rust-lang.org/std/thread/struct.LocalKey.html#method.try_with
7717[`Option::cloned`]: https://doc.rust-lang.org/std/option/enum.Option.html#method.cloned
7718[`btree_map::Entry::and_modify`]: https://doc.rust-lang.org/std/collections/btree_map/enum.Entry.html#method.and_modify
7719[`fs::read_to_string`]: https://doc.rust-lang.org/std/fs/fn.read_to_string.html
7720[`fs::read`]: https://doc.rust-lang.org/std/fs/fn.read.html
7721[`fs::write`]: https://doc.rust-lang.org/std/fs/fn.write.html
7722[`hash_map::Entry::and_modify`]: https://doc.rust-lang.org/std/collections/hash_map/enum.Entry.html#method.and_modify
7723[`iter::FusedIterator`]: https://doc.rust-lang.org/std/iter/trait.FusedIterator.html
7724[`ops::RangeInclusive`]: https://doc.rust-lang.org/std/ops/struct.RangeInclusive.html
7725[`ops::RangeToInclusive`]: https://doc.rust-lang.org/std/ops/struct.RangeToInclusive.html
7726[`process::id`]: https://doc.rust-lang.org/std/process/fn.id.html
7727[`slice::rotate_left`]: https://doc.rust-lang.org/std/primitive.slice.html#method.rotate_left
7728[`slice::rotate_right`]: https://doc.rust-lang.org/std/primitive.slice.html#method.rotate_right
7729[`String::retain`]: https://doc.rust-lang.org/std/string/struct.String.html#method.retain
7730[cargo/5041]: https://github.com/rust-lang/cargo/pull/5041
7731[cargo/5083]: https://github.com/rust-lang/cargo/pull/5083
7732
7733
7734Version 1.25.0 (2018-03-29)
7735==========================
7736
7737Language
7738--------
7739- [The `#[repr(align(x))]` attribute is now stable.][47006] [RFC 1358]
7740- [You can now use nested groups of imports.][47948]
7741 e.g. `use std::{fs::File, io::Read, path::{Path, PathBuf}};`
7742- [You can now have `|` at the start of a match arm.][47947] e.g.
7743```rust
7744enum Foo { A, B, C }
7745
7746fn main() {
7747 let x = Foo::A;
7748 match x {
7749 | Foo::A
7750 | Foo::B => println!("AB"),
7751 | Foo::C => println!("C"),
7752 }
7753}
7754```
7755
7756Compiler
7757--------
7758- [Upgraded to LLVM 6.][47828]
7759- [Added `-C lto=val` option.][47521]
7760- [Added `i586-unknown-linux-musl` target][47282]
7761
7762Libraries
7763---------
7764- [Impl Send for `process::Command` on Unix.][47760]
7765- [Impl PartialEq and Eq for `ParseCharError`.][47790]
7766- [`UnsafeCell::into_inner` is now safe.][47204]
7767- [Implement libstd for CloudABI.][47268]
7768- [`Float::{from_bits, to_bits}` is now available in libcore.][46931]
7769- [Implement `AsRef<Path>` for Component][46985]
7770- [Implemented `Write` for `Cursor<&mut Vec<u8>>`][46830]
7771- [Moved `Duration` to libcore.][46666]
7772
7773Stabilized APIs
7774---------------
7775- [`Location::column`]
7776- [`ptr::NonNull`]
7777
7778The following functions can now be used in a constant expression.
7779eg. `static MINUTE: Duration = Duration::from_secs(60);`
7780- [`Duration::new`][47300]
7781- [`Duration::from_secs`][47300]
7782- [`Duration::from_millis`][47300]
7783
7784Cargo
7785-----
7786- [`cargo new` no longer removes `rust` or `rs` prefixes/suffixes.][cargo/5013]
7787- [`cargo new` now defaults to creating a binary crate, instead of a
7788 library crate.][cargo/5029]
7789
7790Misc
7791----
7792- [Rust by example is now shipped with new releases][46196]
7793
7794Compatibility Notes
7795-------------------
7796- [Deprecated `net::lookup_host`.][47510]
7797- [`rustdoc` has switched to pulldown as the default markdown renderer.][47398]
7798- The borrow checker was sometimes incorrectly permitting overlapping borrows
7799 around indexing operations (see [#47349][47349]). This has been fixed (which also
7800 enabled some correct code that used to cause errors (e.g. [#33903][33903] and [#46095][46095]).
7801- [Removed deprecated unstable attribute `#[simd]`.][47251]
7802
7803[33903]: https://github.com/rust-lang/rust/pull/33903
7804[47947]: https://github.com/rust-lang/rust/pull/47947
7805[47948]: https://github.com/rust-lang/rust/pull/47948
7806[47760]: https://github.com/rust-lang/rust/pull/47760
7807[47790]: https://github.com/rust-lang/rust/pull/47790
7808[47828]: https://github.com/rust-lang/rust/pull/47828
7809[47398]: https://github.com/rust-lang/rust/pull/47398
7810[47510]: https://github.com/rust-lang/rust/pull/47510
7811[47521]: https://github.com/rust-lang/rust/pull/47521
7812[47204]: https://github.com/rust-lang/rust/pull/47204
7813[47251]: https://github.com/rust-lang/rust/pull/47251
7814[47268]: https://github.com/rust-lang/rust/pull/47268
7815[47282]: https://github.com/rust-lang/rust/pull/47282
7816[47300]: https://github.com/rust-lang/rust/pull/47300
7817[47349]: https://github.com/rust-lang/rust/pull/47349
7818[46931]: https://github.com/rust-lang/rust/pull/46931
7819[46985]: https://github.com/rust-lang/rust/pull/46985
7820[47006]: https://github.com/rust-lang/rust/pull/47006
7821[46830]: https://github.com/rust-lang/rust/pull/46830
7822[46095]: https://github.com/rust-lang/rust/pull/46095
7823[46666]: https://github.com/rust-lang/rust/pull/46666
7824[46196]: https://github.com/rust-lang/rust/pull/46196
7825[cargo/5013]: https://github.com/rust-lang/cargo/pull/5013
7826[cargo/5029]: https://github.com/rust-lang/cargo/pull/5029
7827[RFC 1358]: https://github.com/rust-lang/rfcs/pull/1358
7828[`Location::column`]: https://doc.rust-lang.org/std/panic/struct.Location.html#method.column
7829[`ptr::NonNull`]: https://doc.rust-lang.org/std/ptr/struct.NonNull.html
7830
7831
7832Version 1.24.1 (2018-03-01)
7833==========================
7834
7835 - [Do not abort when unwinding through FFI][48251]
7836 - [Emit UTF-16 files for linker arguments on Windows][48318]
7837 - [Make the error index generator work again][48308]
7838 - [Cargo will warn on Windows 7 if an update is needed][cargo/5069].
7839
7840[48251]: https://github.com/rust-lang/rust/issues/48251
7841[48308]: https://github.com/rust-lang/rust/issues/48308
7842[48318]: https://github.com/rust-lang/rust/issues/48318
7843[cargo/5069]: https://github.com/rust-lang/cargo/pull/5069
7844
7845
7846Version 1.24.0 (2018-02-15)
7847==========================
7848
7849Language
7850--------
7851- [External `sysv64` ffi is now available.][46528]
7852 eg. `extern "sysv64" fn foo () {}`
7853
7854Compiler
7855--------
7856- [rustc now uses 16 codegen units by default for release builds.][46910]
7857 For the fastest builds, utilize `codegen-units=1`.
7858- [Added `armv4t-unknown-linux-gnueabi` target.][47018]
7859- [Add `aarch64-unknown-openbsd` support][46760]
7860
7861Libraries
7862---------
7863- [`str::find::<char>` now uses memchr.][46735] This should lead to a 10x
7864 improvement in performance in the majority of cases.
7865- [`OsStr`'s `Debug` implementation is now lossless and consistent
7866 with Windows.][46798]
7867- [`time::{SystemTime, Instant}` now implement `Hash`.][46828]
7868- [impl `From<bool>` for `AtomicBool`][46293]
7869- [impl `From<{CString, &CStr}>` for `{Arc<CStr>, Rc<CStr>}`][45990]
7870- [impl `From<{OsString, &OsStr}>` for `{Arc<OsStr>, Rc<OsStr>}`][45990]
7871- [impl `From<{PathBuf, &Path}>` for `{Arc<Path>, Rc<Path>}`][45990]
7872- [float::from_bits now just uses transmute.][46012] This provides
7873 some optimisations from LLVM.
7874- [Copied `AsciiExt` methods onto `char`][46077]
7875- [Remove `T: Sized` requirement on `ptr::is_null()`][46094]
7876- [impl `From<RecvError>` for `{TryRecvError, RecvTimeoutError}`][45506]
7877- [Optimised `f32::{min, max}` to generate more efficient x86 assembly][47080]
7878- [`[u8]::contains` now uses memchr which provides a 3x speed improvement][46713]
7879
7880Stabilized APIs
7881---------------
7882- [`RefCell::replace`]
7883- [`RefCell::swap`]
7884- [`atomic::spin_loop_hint`]
7885
7886The following functions can now be used in a constant expression.
7887eg. `let buffer: [u8; size_of::<usize>()];`, `static COUNTER: AtomicUsize = AtomicUsize::new(1);`
7888
7889- [`AtomicBool::new`][46287]
7890- [`AtomicUsize::new`][46287]
7891- [`AtomicIsize::new`][46287]
7892- [`AtomicPtr::new`][46287]
7893- [`Cell::new`][46287]
7894- [`{integer}::min_value`][46287]
7895- [`{integer}::max_value`][46287]
7896- [`mem::size_of`][46287]
7897- [`mem::align_of`][46287]
7898- [`ptr::null`][46287]
7899- [`ptr::null_mut`][46287]
7900- [`RefCell::new`][46287]
7901- [`UnsafeCell::new`][46287]
7902
7903Cargo
7904-----
7905- [Added a `workspace.default-members` config that
7906 overrides implied `--all` in virtual workspaces.][cargo/4743]
7907- [Enable incremental by default on development builds.][cargo/4817] Also added
7908 configuration keys to `Cargo.toml` and `.cargo/config` to disable on a
7909 per-project or global basis respectively.
7910
7911Misc
7912----
7913
7914Compatibility Notes
7915-------------------
7916- [Floating point types `Debug` impl now always prints a decimal point.][46831]
7917- [`Ipv6Addr` now rejects superfluous `::`'s in IPv6 addresses][46671] This is
7918 in accordance with IETF RFC 4291 §2.2.
7919- [Unwinding will no longer go past FFI boundaries, and will instead abort.][46833]
7920- [`Formatter::flags` method is now deprecated.][46284] The `sign_plus`,
7921 `sign_minus`, `alternate`, and `sign_aware_zero_pad` should be used instead.
7922- [Leading zeros in tuple struct members is now an error][47084]
7923- [`column!()` macro is one-based instead of zero-based][46977]
7924- [`fmt::Arguments` can no longer be shared across threads][45198]
7925- [Access to `#[repr(packed)]` struct fields is now unsafe][44884]
7926- [Cargo sets a different working directory for the compiler][cargo/4788]
7927
7928[44884]: https://github.com/rust-lang/rust/pull/44884
7929[45198]: https://github.com/rust-lang/rust/pull/45198
7930[45506]: https://github.com/rust-lang/rust/pull/45506
7931[45990]: https://github.com/rust-lang/rust/pull/45990
7932[46012]: https://github.com/rust-lang/rust/pull/46012
7933[46077]: https://github.com/rust-lang/rust/pull/46077
7934[46094]: https://github.com/rust-lang/rust/pull/46094
7935[46284]: https://github.com/rust-lang/rust/pull/46284
7936[46287]: https://github.com/rust-lang/rust/pull/46287
7937[46293]: https://github.com/rust-lang/rust/pull/46293
7938[46528]: https://github.com/rust-lang/rust/pull/46528
7939[46671]: https://github.com/rust-lang/rust/pull/46671
7940[46713]: https://github.com/rust-lang/rust/pull/46713
7941[46735]: https://github.com/rust-lang/rust/pull/46735
7942[46760]: https://github.com/rust-lang/rust/pull/46760
7943[46798]: https://github.com/rust-lang/rust/pull/46798
7944[46828]: https://github.com/rust-lang/rust/pull/46828
7945[46831]: https://github.com/rust-lang/rust/pull/46831
7946[46833]: https://github.com/rust-lang/rust/pull/46833
7947[46910]: https://github.com/rust-lang/rust/pull/46910
7948[46977]: https://github.com/rust-lang/rust/pull/46977
7949[47018]: https://github.com/rust-lang/rust/pull/47018
7950[47080]: https://github.com/rust-lang/rust/pull/47080
7951[47084]: https://github.com/rust-lang/rust/pull/47084
7952[cargo/4743]: https://github.com/rust-lang/cargo/pull/4743
7953[cargo/4788]: https://github.com/rust-lang/cargo/pull/4788
7954[cargo/4817]: https://github.com/rust-lang/cargo/pull/4817
7955[`RefCell::replace`]: https://doc.rust-lang.org/std/cell/struct.RefCell.html#method.replace
7956[`RefCell::swap`]: https://doc.rust-lang.org/std/cell/struct.RefCell.html#method.swap
7957[`atomic::spin_loop_hint`]: https://doc.rust-lang.org/std/sync/atomic/fn.spin_loop_hint.html
7958
7959
7960Version 1.23.0 (2018-01-04)
7961==========================
7962
7963Language
7964--------
7965- [Arbitrary `auto` traits are now permitted in trait objects.][45772]
7966- [rustc now uses subtyping on the left hand side of binary operations.][45435]
7967 Which should fix some confusing errors in some operations.
7968
7969Compiler
7970--------
7971- [Enabled `TrapUnreachable` in LLVM which should mitigate the impact of
7972 undefined behavior.][45920]
7973- [rustc now suggests renaming import if names clash.][45660]
7974- [Display errors/warnings correctly when there are zero-width or
7975 wide characters.][45711]
7976- [rustc now avoids unnecessary copies of arguments that are
7977 simple bindings][45380] This should improve memory usage on average by 5-10%.
7978- [Updated musl used to build musl rustc to 1.1.17][45393]
7979
7980Libraries
7981---------
7982- [Allow a trailing comma in `assert_eq/ne` macro][45887]
7983- [Implement Hash for raw pointers to unsized types][45483]
7984- [impl `From<*mut T>` for `AtomicPtr<T>`][45610]
7985- [impl `From<usize/isize>` for `AtomicUsize/AtomicIsize`.][45610]
7986- [Removed the `T: Sync` requirement for `RwLock<T>: Send`][45267]
7987- [Removed `T: Sized` requirement for `{<*const T>, <*mut T>}::as_ref`
7988 and `<*mut T>::as_mut`][44932]
7989- [Optimized `Thread::{park, unpark}` implementation][45524]
7990- [Improved `SliceExt::binary_search` performance.][45333]
7991- [impl `FromIterator<()>` for `()`][45379]
7992- [Copied `AsciiExt` trait methods to primitive types.][44042] Use of `AsciiExt`
7993 is now deprecated.
7994
7995Stabilized APIs
7996---------------
7997
7998Cargo
7999-----
8000- [Cargo now supports uninstallation of multiple packages][cargo/4561]
8001 eg. `cargo uninstall foo bar` uninstalls `foo` and `bar`.
8002- [Added unit test checking to `cargo check`][cargo/4592]
8003- [Cargo now lets you install a specific version
8004 using `cargo install --version`][cargo/4637]
8005
8006Misc
8007----
8008- [Releases now ship with the Cargo book documentation.][45692]
8009- [rustdoc now prints rendering warnings on every run.][45324]
8010
8011Compatibility Notes
8012-------------------
8013- [Changes have been made to type equality to make it more correct,
8014 in rare cases this could break some code.][45853] [Tracking issue for
8015 further information][45852]
8016- [`char::escape_debug` now uses Unicode 10 over 9.][45571]
8017- [Upgraded Android SDK to 27, and NDK to r15c.][45580] This drops support for
8018 Android 9, the minimum supported version is Android 14.
8019- [Bumped the minimum LLVM to 3.9][45326]
8020
8021[44042]: https://github.com/rust-lang/rust/pull/44042
8022[44932]: https://github.com/rust-lang/rust/pull/44932
8023[45267]: https://github.com/rust-lang/rust/pull/45267
8024[45324]: https://github.com/rust-lang/rust/pull/45324
8025[45326]: https://github.com/rust-lang/rust/pull/45326
8026[45333]: https://github.com/rust-lang/rust/pull/45333
8027[45379]: https://github.com/rust-lang/rust/pull/45379
8028[45380]: https://github.com/rust-lang/rust/pull/45380
8029[45393]: https://github.com/rust-lang/rust/pull/45393
8030[45435]: https://github.com/rust-lang/rust/pull/45435
8031[45483]: https://github.com/rust-lang/rust/pull/45483
8032[45524]: https://github.com/rust-lang/rust/pull/45524
8033[45571]: https://github.com/rust-lang/rust/pull/45571
8034[45580]: https://github.com/rust-lang/rust/pull/45580
8035[45610]: https://github.com/rust-lang/rust/pull/45610
8036[45660]: https://github.com/rust-lang/rust/pull/45660
8037[45692]: https://github.com/rust-lang/rust/pull/45692
8038[45711]: https://github.com/rust-lang/rust/pull/45711
8039[45772]: https://github.com/rust-lang/rust/pull/45772
8040[45852]: https://github.com/rust-lang/rust/issues/45852
8041[45853]: https://github.com/rust-lang/rust/pull/45853
8042[45887]: https://github.com/rust-lang/rust/pull/45887
8043[45920]: https://github.com/rust-lang/rust/pull/45920
8044[cargo/4561]: https://github.com/rust-lang/cargo/pull/4561
8045[cargo/4592]: https://github.com/rust-lang/cargo/pull/4592
8046[cargo/4637]: https://github.com/rust-lang/cargo/pull/4637
8047
8048
8049Version 1.22.1 (2017-11-22)
8050==========================
8051
8052- [Update Cargo to fix an issue with macOS 10.13 "High Sierra"][46183]
8053
8054[46183]: https://github.com/rust-lang/rust/pull/46183
8055
8056Version 1.22.0 (2017-11-22)
8057==========================
8058
8059Language
8060--------
8061- [`non_snake_case` lint now allows extern no-mangle functions][44966]
8062- [Now accepts underscores in unicode escapes][43716]
8063- [`T op= &T` now works for numeric types.][44287] eg. `let mut x = 2; x += &8;`
8064- [types that impl `Drop` are now allowed in `const` and `static` types][44456]
8065
8066Compiler
8067--------
8068- [rustc now defaults to having 16 codegen units at debug on supported platforms.][45064]
8069- [rustc will no longer inline in codegen units when compiling for debug][45075]
8070 This should decrease compile times for debug builds.
8071- [strict memory alignment now enabled on ARMv6][45094]
8072- [Remove support for the PNaCl target `le32-unknown-nacl`][45041]
8073
8074Libraries
8075---------
8076- [Allow atomic operations up to 32 bits
8077 on `armv5te_unknown_linux_gnueabi`][44978]
8078- [`Box<Error>` now impls `From<Cow<str>>`][44466]
8079- [`std::mem::Discriminant` is now guaranteed to be `Send + Sync`][45095]
8080- [`fs::copy` now returns the length of the main stream on NTFS.][44895]
8081- [Properly detect overflow in `Instant += Duration`.][44220]
8082- [impl `Hasher` for `{&mut Hasher, Box<Hasher>}`][44015]
8083- [impl `fmt::Debug` for `SplitWhitespace`.][44303]
8084- [`Option<T>` now impls `Try`][42526] This allows for using `?` with `Option` types.
8085
8086Stabilized APIs
8087---------------
8088
8089Cargo
8090-----
8091- [Cargo will now build multi file examples in subdirectories of the `examples`
8092 folder that have a `main.rs` file.][cargo/4496]
8093- [Changed `[root]` to `[package]` in `Cargo.lock`][cargo/4571] Packages with
8094 the old format will continue to work and can be updated with `cargo update`.
8095- [Now supports vendoring git repositories][cargo/3992]
8096
8097Misc
8098----
8099- [`libbacktrace` is now available on Apple platforms.][44251]
8100- [Stabilised the `compile_fail` attribute for code fences in doc-comments.][43949]
8101 This now lets you specify that a given code example will fail to compile.
8102
8103Compatibility Notes
8104-------------------
8105- [The minimum Android version that rustc can build for has been bumped
8106 to `4.0` from `2.3`][45656]
8107- [Allowing `T op= &T` for numeric types has broken some type
8108 inference cases][45480]
8109
8110
8111[42526]: https://github.com/rust-lang/rust/pull/42526
8112[43716]: https://github.com/rust-lang/rust/pull/43716
8113[43949]: https://github.com/rust-lang/rust/pull/43949
8114[44015]: https://github.com/rust-lang/rust/pull/44015
8115[44220]: https://github.com/rust-lang/rust/pull/44220
8116[44251]: https://github.com/rust-lang/rust/pull/44251
8117[44287]: https://github.com/rust-lang/rust/pull/44287
8118[44303]: https://github.com/rust-lang/rust/pull/44303
8119[44456]: https://github.com/rust-lang/rust/pull/44456
8120[44466]: https://github.com/rust-lang/rust/pull/44466
8121[44895]: https://github.com/rust-lang/rust/pull/44895
8122[44966]: https://github.com/rust-lang/rust/pull/44966
8123[44978]: https://github.com/rust-lang/rust/pull/44978
8124[45041]: https://github.com/rust-lang/rust/pull/45041
8125[45064]: https://github.com/rust-lang/rust/pull/45064
8126[45075]: https://github.com/rust-lang/rust/pull/45075
8127[45094]: https://github.com/rust-lang/rust/pull/45094
8128[45095]: https://github.com/rust-lang/rust/pull/45095
8129[45480]: https://github.com/rust-lang/rust/issues/45480
8130[45656]: https://github.com/rust-lang/rust/pull/45656
8131[cargo/3992]: https://github.com/rust-lang/cargo/pull/3992
8132[cargo/4496]: https://github.com/rust-lang/cargo/pull/4496
8133[cargo/4571]: https://github.com/rust-lang/cargo/pull/4571
8134
8135
8136
8137
8138
8139
8140Version 1.21.0 (2017-10-12)
8141==========================
8142
8143Language
8144--------
8145- [You can now use static references for literals.][43838]
8146 Example:
8147 ```rust
8148 fn main() {
8149 let x: &'static u32 = &0;
8150 }
8151 ```
8152- [Relaxed path syntax. Optional `::` before `<` is now allowed in all contexts.][43540]
8153 Example:
8154 ```rust
8155 my_macro!(Vec<i32>::new); // Always worked
8156 my_macro!(Vec::<i32>::new); // Now works
8157 ```
8158
8159Compiler
8160--------
8161- [Upgraded jemalloc to 4.5.0][43911]
8162- [Enabled unwinding panics on Redox][43917]
8163- [Now runs LLVM in parallel during translation phase.][43506]
8164 This should reduce peak memory usage.
8165
8166Libraries
8167---------
8168- [Generate builtin impls for `Clone` for all arrays and tuples that
8169 are `T: Clone`][43690]
8170- [`Stdin`, `Stdout`, and `Stderr` now implement `AsRawFd`.][43459]
8171- [`Rc` and `Arc` now implement `From<&[T]> where T: Clone`, `From<str>`,
8172 `From<String>`, `From<Box<T>> where T: ?Sized`, and `From<Vec<T>>`.][42565]
8173
8174Stabilized APIs
8175---------------
8176
8177[`std::mem::discriminant`]
8178
8179Cargo
8180-----
8181- [You can now call `cargo install` with multiple package names][cargo/4216]
8182- [Cargo commands inside a virtual workspace will now implicitly
8183 pass `--all`][cargo/4335]
8184- [Added a `[patch]` section to `Cargo.toml` to handle
8185 prepublication dependencies][cargo/4123] [RFC 1969]
8186- [`include` & `exclude` fields in `Cargo.toml` now accept gitignore
8187 like patterns][cargo/4270]
8188- [Added the `--all-targets` option][cargo/4400]
8189- [Using required dependencies as a feature is now deprecated and emits
8190 a warning][cargo/4364]
8191
8192
8193Misc
8194----
8195- [Cargo docs are moving][43916]
8196 to [doc.rust-lang.org/cargo](https://doc.rust-lang.org/cargo)
8197- [The rustdoc book is now available][43863]
8198 at [doc.rust-lang.org/rustdoc](https://doc.rust-lang.org/rustdoc)
8199- [Added a preview of RLS has been made available through rustup][44204]
8200 Install with `rustup component add rls-preview`
8201- [`std::os` documentation for Unix, Linux, and Windows now appears on doc.rust-lang.org][43348]
8202 Previously only showed `std::os::unix`.
8203
8204Compatibility Notes
8205-------------------
8206- [Changes in method matching against higher-ranked types][43880] This may cause
8207 breakage in subtyping corner cases. [A more in-depth explanation is available.][info/43880]
8208- [rustc's JSON error output's byte position start at top of file.][42973]
8209 Was previously relative to the rustc's internal `CodeMap` struct which
8210 required the unstable library `libsyntax` to correctly use.
8211- [`unused_results` lint no longer ignores booleans][43728]
8212
8213[42565]: https://github.com/rust-lang/rust/pull/42565
8214[42973]: https://github.com/rust-lang/rust/pull/42973
8215[43348]: https://github.com/rust-lang/rust/pull/43348
8216[43459]: https://github.com/rust-lang/rust/pull/43459
8217[43506]: https://github.com/rust-lang/rust/pull/43506
8218[43540]: https://github.com/rust-lang/rust/pull/43540
8219[43690]: https://github.com/rust-lang/rust/pull/43690
8220[43728]: https://github.com/rust-lang/rust/pull/43728
8221[43838]: https://github.com/rust-lang/rust/pull/43838
8222[43863]: https://github.com/rust-lang/rust/pull/43863
8223[43880]: https://github.com/rust-lang/rust/pull/43880
8224[43911]: https://github.com/rust-lang/rust/pull/43911
8225[43916]: https://github.com/rust-lang/rust/pull/43916
8226[43917]: https://github.com/rust-lang/rust/pull/43917
8227[44204]: https://github.com/rust-lang/rust/pull/44204
8228[cargo/4123]: https://github.com/rust-lang/cargo/pull/4123
8229[cargo/4216]: https://github.com/rust-lang/cargo/pull/4216
8230[cargo/4270]: https://github.com/rust-lang/cargo/pull/4270
8231[cargo/4335]: https://github.com/rust-lang/cargo/pull/4335
8232[cargo/4364]: https://github.com/rust-lang/cargo/pull/4364
8233[cargo/4400]: https://github.com/rust-lang/cargo/pull/4400
8234[RFC 1969]: https://github.com/rust-lang/rfcs/pull/1969
8235[info/43880]: https://github.com/rust-lang/rust/issues/44224#issuecomment-330058902
8236[`std::mem::discriminant`]: https://doc.rust-lang.org/std/mem/fn.discriminant.html
8237
8238Version 1.20.0 (2017-08-31)
8239===========================
8240
8241Language
8242--------
8243- [Associated constants are now stabilised.][42809]
8244- [A lot of macro bugs are now fixed.][42913]
8245
8246Compiler
8247--------
8248
8249- [Struct fields are now properly coerced to the expected field type.][42807]
8250- [Enabled wasm LLVM backend][42571] WASM can now be built with the
8251 `wasm32-experimental-emscripten` target.
8252- [Changed some of the error messages to be more helpful.][42033]
8253- [Add support for RELRO(RELocation Read-Only) for platforms that support
8254 it.][43170]
8255- [rustc now reports the total number of errors on compilation failure][43015]
8256 previously this was only the number of errors in the pass that failed.
8257- [Expansion in rustc has been sped up 29x.][42533]
8258- [added `msp430-none-elf` target.][43099]
8259- [rustc will now suggest one-argument enum variant to fix type mismatch when
8260 applicable][43178]
8261- [Fixes backtraces on Redox][43228]
8262- [rustc now identifies different versions of same crate when absolute paths of
8263 different types match in an error message.][42826]
8264
8265Libraries
8266---------
8267
8268
8269- [Relaxed Debug constraints on `{HashMap,BTreeMap}::{Keys,Values}`.][42854]
8270- [Impl `PartialEq`, `Eq`, `PartialOrd`, `Ord`, `Debug`, `Hash` for unsized
8271 tuples.][43011]
8272- [Impl `fmt::{Display, Debug}` for `Ref`, `RefMut`, `MutexGuard`,
8273 `RwLockReadGuard`, `RwLockWriteGuard`][42822]
8274- [Impl `Clone` for `DefaultHasher`.][42799]
8275- [Impl `Sync` for `SyncSender`.][42397]
8276- [Impl `FromStr` for `char`][42271]
8277- [Fixed how `{f32, f64}::{is_sign_negative, is_sign_positive}` handles
8278 NaN.][42431]
8279- [allow messages in the `unimplemented!()` macro.][42155]
8280 ie. `unimplemented!("Waiting for 1.21 to be stable")`
8281- [`pub(restricted)` is now supported in the `thread_local!` macro.][43185]
8282- [Upgrade to Unicode 10.0.0][42999]
8283- [Reimplemented `{f32, f64}::{min, max}` in Rust instead of using CMath.][42430]
8284- [Skip the main thread's manual stack guard on Linux][43072]
8285- [Iterator::nth for `ops::{Range, RangeFrom}` is now done in *O*(1) time][43077]
8286- [`#[repr(align(N))]` attribute max number is now 2^31 - 1.][43097] This was
8287 previously 2^15.
8288- [`{OsStr, Path}::Display` now avoids allocations where possible][42613]
8289
8290Stabilized APIs
8291---------------
8292
8293- [`CStr::into_c_string`]
8294- [`CString::as_c_str`]
8295- [`CString::into_boxed_c_str`]
8296- [`Chain::get_mut`]
8297- [`Chain::get_ref`]
8298- [`Chain::into_inner`]
8299- [`Option::get_or_insert_with`]
8300- [`Option::get_or_insert`]
8301- [`OsStr::into_os_string`]
8302- [`OsString::into_boxed_os_str`]
8303- [`Take::get_mut`]
8304- [`Take::get_ref`]
8305- [`Utf8Error::error_len`]
8306- [`char::EscapeDebug`]
8307- [`char::escape_debug`]
8308- [`compile_error!`]
8309- [`f32::from_bits`]
8310- [`f32::to_bits`]
8311- [`f64::from_bits`]
8312- [`f64::to_bits`]
8313- [`mem::ManuallyDrop`]
8314- [`slice::sort_unstable_by_key`]
8315- [`slice::sort_unstable_by`]
8316- [`slice::sort_unstable`]
8317- [`str::from_boxed_utf8_unchecked`]
8318- [`str::as_bytes_mut`]
8319- [`str::as_bytes_mut`]
8320- [`str::from_utf8_mut`]
8321- [`str::from_utf8_unchecked_mut`]
8322- [`str::get_mut`]
8323- [`str::get_unchecked_mut`]
8324- [`str::get_unchecked`]
8325- [`str::get`]
8326- [`str::into_boxed_bytes`]
8327
8328
8329Cargo
8330-----
8331- [Cargo API token location moved from `~/.cargo/config` to
8332 `~/.cargo/credentials`.][cargo/3978]
8333- [Cargo will now build `main.rs` binaries that are in sub-directories of
8334 `src/bin`.][cargo/4214] ie. Having `src/bin/server/main.rs` and
8335 `src/bin/client/main.rs` generates `target/debug/server` and `target/debug/client`
8336- [You can now specify version of a binary when installed through
8337 `cargo install` using `--vers`.][cargo/4229]
8338- [Added `--no-fail-fast` flag to cargo to run all benchmarks regardless of
8339 failure.][cargo/4248]
8340- [Changed the convention around which file is the crate root.][cargo/4259]
8341
8342Compatibility Notes
8343-------------------
8344
8345- [Functions with `'static` in their return types will now not be as usable as
8346 if they were using lifetime parameters instead.][42417]
8347- [The reimplementation of `{f32, f64}::is_sign_{negative, positive}` now
8348 takes the sign of NaN into account where previously didn't.][42430]
8349
8350[42033]: https://github.com/rust-lang/rust/pull/42033
8351[42155]: https://github.com/rust-lang/rust/pull/42155
8352[42271]: https://github.com/rust-lang/rust/pull/42271
8353[42397]: https://github.com/rust-lang/rust/pull/42397
8354[42417]: https://github.com/rust-lang/rust/pull/42417
8355[42430]: https://github.com/rust-lang/rust/pull/42430
8356[42431]: https://github.com/rust-lang/rust/pull/42431
8357[42533]: https://github.com/rust-lang/rust/pull/42533
8358[42571]: https://github.com/rust-lang/rust/pull/42571
8359[42613]: https://github.com/rust-lang/rust/pull/42613
8360[42799]: https://github.com/rust-lang/rust/pull/42799
8361[42807]: https://github.com/rust-lang/rust/pull/42807
8362[42809]: https://github.com/rust-lang/rust/pull/42809
8363[42822]: https://github.com/rust-lang/rust/pull/42822
8364[42826]: https://github.com/rust-lang/rust/pull/42826
8365[42854]: https://github.com/rust-lang/rust/pull/42854
8366[42913]: https://github.com/rust-lang/rust/pull/42913
8367[42999]: https://github.com/rust-lang/rust/pull/42999
8368[43011]: https://github.com/rust-lang/rust/pull/43011
8369[43015]: https://github.com/rust-lang/rust/pull/43015
8370[43072]: https://github.com/rust-lang/rust/pull/43072
8371[43077]: https://github.com/rust-lang/rust/pull/43077
8372[43097]: https://github.com/rust-lang/rust/pull/43097
8373[43099]: https://github.com/rust-lang/rust/pull/43099
8374[43170]: https://github.com/rust-lang/rust/pull/43170
8375[43178]: https://github.com/rust-lang/rust/pull/43178
8376[43185]: https://github.com/rust-lang/rust/pull/43185
8377[43228]: https://github.com/rust-lang/rust/pull/43228
8378[cargo/3978]: https://github.com/rust-lang/cargo/pull/3978
8379[cargo/4214]: https://github.com/rust-lang/cargo/pull/4214
8380[cargo/4229]: https://github.com/rust-lang/cargo/pull/4229
8381[cargo/4248]: https://github.com/rust-lang/cargo/pull/4248
8382[cargo/4259]: https://github.com/rust-lang/cargo/pull/4259
8383[`CStr::into_c_string`]: https://doc.rust-lang.org/std/ffi/struct.CStr.html#method.into_c_string
8384[`CString::as_c_str`]: https://doc.rust-lang.org/std/ffi/struct.CString.html#method.as_c_str
8385[`CString::into_boxed_c_str`]: https://doc.rust-lang.org/std/ffi/struct.CString.html#method.into_boxed_c_str
8386[`Chain::get_mut`]: https://doc.rust-lang.org/std/io/struct.Chain.html#method.get_mut
8387[`Chain::get_ref`]: https://doc.rust-lang.org/std/io/struct.Chain.html#method.get_ref
8388[`Chain::into_inner`]: https://doc.rust-lang.org/std/io/struct.Chain.html#method.into_inner
8389[`Option::get_or_insert_with`]: https://doc.rust-lang.org/std/option/enum.Option.html#method.get_or_insert_with
8390[`Option::get_or_insert`]: https://doc.rust-lang.org/std/option/enum.Option.html#method.get_or_insert
8391[`OsStr::into_os_string`]: https://doc.rust-lang.org/std/ffi/struct.OsStr.html#method.into_os_string
8392[`OsString::into_boxed_os_str`]: https://doc.rust-lang.org/std/ffi/struct.OsString.html#method.into_boxed_os_str
8393[`Take::get_mut`]: https://doc.rust-lang.org/std/io/struct.Take.html#method.get_mut
8394[`Take::get_ref`]: https://doc.rust-lang.org/std/io/struct.Take.html#method.get_ref
8395[`Utf8Error::error_len`]: https://doc.rust-lang.org/std/str/struct.Utf8Error.html#method.error_len
8396[`char::EscapeDebug`]: https://doc.rust-lang.org/std/char/struct.EscapeDebug.html
8397[`char::escape_debug`]: https://doc.rust-lang.org/std/primitive.char.html#method.escape_debug
8398[`compile_error!`]: https://doc.rust-lang.org/std/macro.compile_error.html
8399[`f32::from_bits`]: https://doc.rust-lang.org/std/primitive.f32.html#method.from_bits
8400[`f32::to_bits`]: https://doc.rust-lang.org/std/primitive.f32.html#method.to_bits
8401[`f64::from_bits`]: https://doc.rust-lang.org/std/primitive.f64.html#method.from_bits
8402[`f64::to_bits`]: https://doc.rust-lang.org/std/primitive.f64.html#method.to_bits
8403[`mem::ManuallyDrop`]: https://doc.rust-lang.org/std/mem/union.ManuallyDrop.html
8404[`slice::sort_unstable_by_key`]: https://doc.rust-lang.org/std/primitive.slice.html#method.sort_unstable_by_key
8405[`slice::sort_unstable_by`]: https://doc.rust-lang.org/std/primitive.slice.html#method.sort_unstable_by
8406[`slice::sort_unstable`]: https://doc.rust-lang.org/std/primitive.slice.html#method.sort_unstable
8407[`str::from_boxed_utf8_unchecked`]: https://doc.rust-lang.org/std/str/fn.from_boxed_utf8_unchecked.html
8408[`str::as_bytes_mut`]: https://doc.rust-lang.org/std/primitive.str.html#method.as_bytes_mut
8409[`str::from_utf8_mut`]: https://doc.rust-lang.org/std/str/fn.from_utf8_mut.html
8410[`str::from_utf8_unchecked_mut`]: https://doc.rust-lang.org/std/str/fn.from_utf8_unchecked_mut.html
8411[`str::get_mut`]: https://doc.rust-lang.org/std/primitive.str.html#method.get_mut
8412[`str::get_unchecked_mut`]: https://doc.rust-lang.org/std/primitive.str.html#method.get_unchecked_mut
8413[`str::get_unchecked`]: https://doc.rust-lang.org/std/primitive.str.html#method.get_unchecked
8414[`str::get`]: https://doc.rust-lang.org/std/primitive.str.html#method.get
8415[`str::into_boxed_bytes`]: https://doc.rust-lang.org/std/primitive.str.html#method.into_boxed_bytes
8416
8417
8418Version 1.19.0 (2017-07-20)
8419===========================
8420
8421Language
8422--------
8423
8424- [Numeric fields can now be used for creating tuple structs.][41145] [RFC 1506]
8425 For example `struct Point(u32, u32); let x = Point { 0: 7, 1: 0 };`.
8426- [Macro recursion limit increased to 1024 from 64.][41676]
8427- [Added lint for detecting unused macros.][41907]
8428- [`loop` can now return a value with `break`.][42016] [RFC 1624]
8429 For example: `let x = loop { break 7; };`
8430- [C compatible `union`s are now available.][42068] [RFC 1444] They can only
8431 contain `Copy` types and cannot have a `Drop` implementation.
8432 Example: `union Foo { bar: u8, baz: usize }`
8433- [Non capturing closures can now be coerced into `fn`s,][42162] [RFC 1558]
8434 Example: `let foo: fn(u8) -> u8 = |v: u8| { v };`
8435
8436Compiler
8437--------
8438
8439- [Add support for bootstrapping the Rust compiler toolchain on Android.][41370]
8440- [Change `arm-linux-androideabi` to correspond to the `armeabi`
8441 official ABI.][41656] If you wish to continue targeting the `armeabi-v7a` ABI
8442 you should use `--target armv7-linux-androideabi`.
8443- [Fixed ICE when removing a source file between compilation sessions.][41873]
8444- [Minor optimisation of string operations.][42037]
8445- [Compiler error message is now `aborting due to previous error(s)` instead of
8446 `aborting due to N previous errors`][42150] This was previously inaccurate and
8447 would only count certain kinds of errors.
8448- [The compiler now supports Visual Studio 2017][42225]
8449- [The compiler is now built against LLVM 4.0.1 by default][42948]
8450- [Added a lot][42264] of [new error codes][42302]
8451- [Added `target-feature=+crt-static` option][37406] [RFC 1721] Which allows
8452 libraries with C Run-time Libraries(CRT) to be statically linked.
8453- [Fixed various ARM codegen bugs][42740]
8454
8455Libraries
8456---------
8457
8458- [`String` now implements `FromIterator<Cow<'a, str>>` and
8459 `Extend<Cow<'a, str>>`][41449]
8460- [`Vec` now implements `From<&mut [T]>`][41530]
8461- [`Box<[u8]>` now implements `From<Box<str>>`][41258]
8462- [`SplitWhitespace` now implements `Clone`][41659]
8463- [`[u8]::reverse` is now 5x faster and `[u16]::reverse` is now
8464 1.5x faster][41764]
8465- [`eprint!` and `eprintln!` macros added to prelude.][41192] Same as the `print!`
8466 macros, but for printing to stderr.
8467
8468Stabilized APIs
8469---------------
8470
8471- [`OsString::shrink_to_fit`]
8472- [`cmp::Reverse`]
8473- [`Command::envs`]
8474- [`thread::ThreadId`]
8475
8476Cargo
8477-----
8478
8479- [Build scripts can now add environment variables to the environment
8480 the crate is being compiled in.
8481 Example: `println!("cargo:rustc-env=FOO=bar");`][cargo/3929]
8482- [Subcommands now replace the current process rather than spawning a new
8483 child process][cargo/3970]
8484- [Workspace members can now accept glob file patterns][cargo/3979]
8485- [Added `--all` flag to the `cargo bench` subcommand to run benchmarks of all
8486 the members in a given workspace.][cargo/3988]
8487- [Updated `libssh2-sys` to 0.2.6][cargo/4008]
8488- [Target directory path is now in the cargo metadata][cargo/4022]
8489- [Cargo no longer checks out a local working directory for the
8490 crates.io index][cargo/4026] This should provide smaller file size for the
8491 registry, and improve cloning times, especially on Windows machines.
8492- [Added an `--exclude` option for excluding certain packages when using the
8493 `--all` option][cargo/4031]
8494- [Cargo will now automatically retry when receiving a 5xx error
8495 from crates.io][cargo/4032]
8496- [The `--features` option now accepts multiple comma or space
8497 delimited values.][cargo/4084]
8498- [Added support for custom target specific runners][cargo/3954]
8499
8500Misc
8501----
8502
8503- [Added `rust-windbg.cmd`][39983] for loading rust `.natvis` files in the
8504 Windows Debugger.
8505- [Rust will now release XZ compressed packages][rust-installer/57]
8506- [rustup will now prefer to download rust packages with
8507 XZ compression][rustup/1100] over GZip packages.
8508- [Added the ability to escape `#` in rust documentation][41785] By adding
8509 additional `#`'s ie. `##` is now `#`
8510
8511Compatibility Notes
8512-------------------
8513
8514- [`MutexGuard<T>` may only be `Sync` if `T` is `Sync`.][41624]
8515- [`-Z` flags are now no longer allowed to be used on the stable
8516 compiler.][41751] This has been a warning for a year previous to this.
8517- [As a result of the `-Z` flag change, the `cargo-check` plugin no
8518 longer works][42844]. Users should migrate to the built-in `check`
8519 command, which has been available since 1.16.
8520- [Ending a float literal with `._` is now a hard error.
8521 Example: `42._` .][41946]
8522- [Any use of a private `extern crate` outside of its module is now a
8523 hard error.][36886] This was previously a warning.
8524- [`use ::self::foo;` is now a hard error.][36888] `self` paths are always
8525 relative while the `::` prefix makes a path absolute, but was ignored and the
8526 path was relative regardless.
8527- [Floating point constants in match patterns is now a hard error][36890]
8528 This was previously a warning.
8529- [Struct or enum constants that don't derive `PartialEq` & `Eq` used
8530 match patterns is now a hard error][36891] This was previously a warning.
8531- [Lifetimes named `'_` are no longer allowed.][36892] This was previously
8532 a warning.
8533- [From the pound escape, lines consisting of multiple `#`s are
8534 now visible][41785]
8535- [It is an error to re-export private enum variants][42460]. This is
8536 known to break a number of crates that depend on an older version of
8537 mustache.
8538- [On Windows, if `VCINSTALLDIR` is set incorrectly, `rustc` will try
8539 to use it to find the linker, and the build will fail where it did
8540 not previously][42607]
8541
8542[36886]: https://github.com/rust-lang/rust/issues/36886
8543[36888]: https://github.com/rust-lang/rust/issues/36888
8544[36890]: https://github.com/rust-lang/rust/issues/36890
8545[36891]: https://github.com/rust-lang/rust/issues/36891
8546[36892]: https://github.com/rust-lang/rust/issues/36892
8547[37406]: https://github.com/rust-lang/rust/issues/37406
8548[39983]: https://github.com/rust-lang/rust/pull/39983
8549[41145]: https://github.com/rust-lang/rust/pull/41145
8550[41192]: https://github.com/rust-lang/rust/pull/41192
8551[41258]: https://github.com/rust-lang/rust/pull/41258
8552[41370]: https://github.com/rust-lang/rust/pull/41370
8553[41449]: https://github.com/rust-lang/rust/pull/41449
8554[41530]: https://github.com/rust-lang/rust/pull/41530
8555[41624]: https://github.com/rust-lang/rust/pull/41624
8556[41656]: https://github.com/rust-lang/rust/pull/41656
8557[41659]: https://github.com/rust-lang/rust/pull/41659
8558[41676]: https://github.com/rust-lang/rust/pull/41676
8559[41751]: https://github.com/rust-lang/rust/pull/41751
8560[41764]: https://github.com/rust-lang/rust/pull/41764
8561[41785]: https://github.com/rust-lang/rust/pull/41785
8562[41873]: https://github.com/rust-lang/rust/pull/41873
8563[41907]: https://github.com/rust-lang/rust/pull/41907
8564[41946]: https://github.com/rust-lang/rust/pull/41946
8565[42016]: https://github.com/rust-lang/rust/pull/42016
8566[42037]: https://github.com/rust-lang/rust/pull/42037
8567[42068]: https://github.com/rust-lang/rust/pull/42068
8568[42150]: https://github.com/rust-lang/rust/pull/42150
8569[42162]: https://github.com/rust-lang/rust/pull/42162
8570[42225]: https://github.com/rust-lang/rust/pull/42225
8571[42264]: https://github.com/rust-lang/rust/pull/42264
8572[42302]: https://github.com/rust-lang/rust/pull/42302
8573[42460]: https://github.com/rust-lang/rust/issues/42460
8574[42607]: https://github.com/rust-lang/rust/issues/42607
8575[42740]: https://github.com/rust-lang/rust/pull/42740
8576[42844]: https://github.com/rust-lang/rust/issues/42844
8577[42948]: https://github.com/rust-lang/rust/pull/42948
8578[RFC 1444]: https://github.com/rust-lang/rfcs/pull/1444
8579[RFC 1506]: https://github.com/rust-lang/rfcs/pull/1506
8580[RFC 1558]: https://github.com/rust-lang/rfcs/pull/1558
8581[RFC 1624]: https://github.com/rust-lang/rfcs/pull/1624
8582[RFC 1721]: https://github.com/rust-lang/rfcs/pull/1721
8583[`Command::envs`]: https://doc.rust-lang.org/std/process/struct.Command.html#method.envs
8584[`OsString::shrink_to_fit`]: https://doc.rust-lang.org/std/ffi/struct.OsString.html#method.shrink_to_fit
8585[`cmp::Reverse`]: https://doc.rust-lang.org/std/cmp/struct.Reverse.html
8586[`thread::ThreadId`]: https://doc.rust-lang.org/std/thread/struct.ThreadId.html
8587[cargo/3929]: https://github.com/rust-lang/cargo/pull/3929
8588[cargo/3954]: https://github.com/rust-lang/cargo/pull/3954
8589[cargo/3970]: https://github.com/rust-lang/cargo/pull/3970
8590[cargo/3979]: https://github.com/rust-lang/cargo/pull/3979
8591[cargo/3988]: https://github.com/rust-lang/cargo/pull/3988
8592[cargo/4008]: https://github.com/rust-lang/cargo/pull/4008
8593[cargo/4022]: https://github.com/rust-lang/cargo/pull/4022
8594[cargo/4026]: https://github.com/rust-lang/cargo/pull/4026
8595[cargo/4031]: https://github.com/rust-lang/cargo/pull/4031
8596[cargo/4032]: https://github.com/rust-lang/cargo/pull/4032
8597[cargo/4084]: https://github.com/rust-lang/cargo/pull/4084
8598[rust-installer/57]: https://github.com/rust-lang/rust-installer/pull/57
8599[rustup/1100]: https://github.com/rust-lang-nursery/rustup.rs/pull/1100
8600
8601
8602Version 1.18.0 (2017-06-08)
8603===========================
8604
8605Language
8606--------
8607
8608- [Stabilize pub(restricted)][40556] `pub` can now accept a module path to
8609 make the item visible to just that module tree. Also accepts the keyword
8610 `crate` to make something public to the whole crate but not users of the
8611 library. Example: `pub(crate) mod utils;`. [RFC 1422].
8612- [Stabilize `#![windows_subsystem]` attribute][40870] conservative exposure of the
8613 `/SUBSYSTEM` linker flag on Windows platforms. [RFC 1665].
8614- [Refactor of trait object type parsing][40043] Now `ty` in macros can accept
8615 types like `Write + Send`, trailing `+` are now supported in trait objects,
8616 and better error reporting for trait objects starting with `?Sized`.
8617- [0e+10 is now a valid floating point literal][40589]
8618- [Now warns if you bind a lifetime parameter to 'static][40734]
8619- [Tuples, Enum variant fields, and structs with no `repr` attribute or with
8620 `#[repr(Rust)]` are reordered to minimize padding and produce a smaller
8621 representation in some cases.][40377]
8622
8623Compiler
8624--------
8625
8626- [rustc can now emit mir with `--emit mir`][39891]
8627- [Improved LLVM IR for trivial functions][40367]
8628- [Added explanation for E0090(Wrong number of lifetimes are supplied)][40723]
8629- [rustc compilation is now 15%-20% faster][41469] Thanks to optimisation
8630 opportunities found through profiling
8631- [Improved backtrace formatting when panicking][38165]
8632
8633Libraries
8634---------
8635
8636- [Specialized `Vec::from_iter` being passed `vec::IntoIter`][40731] if the
8637 iterator hasn't been advanced the original `Vec` is reassembled with no actual
8638 iteration or reallocation.
8639- [Simplified HashMap Bucket interface][40561] provides performance
8640 improvements for iterating and cloning.
8641- [Specialize Vec::from_elem to use calloc][40409]
8642- [Fixed Race condition in fs::create_dir_all][39799]
8643- [No longer caching stdio on Windows][40516]
8644- [Optimized insertion sort in slice][40807] insertion sort in some cases
8645 2.50%~ faster and in one case now 12.50% faster.
8646- [Optimized `AtomicBool::fetch_nand`][41143]
8647
8648Stabilized APIs
8649---------------
8650
8651- [`Child::try_wait`]
8652- [`HashMap::retain`]
8653- [`HashSet::retain`]
8654- [`PeekMut::pop`]
8655- [`TcpStream::peek`]
8656- [`UdpSocket::peek`]
8657- [`UdpSocket::peek_from`]
8658
8659Cargo
8660-----
8661
8662- [Added partial Pijul support][cargo/3842] Pijul is a version control system in Rust.
8663 You can now create new cargo projects with Pijul using `cargo new --vcs pijul`
8664- [Now always emits build script warnings for crates that fail to build][cargo/3847]
8665- [Added Android build support][cargo/3885]
8666- [Added `--bins` and `--tests` flags][cargo/3901] now you can build all programs
8667 of a certain type, for example `cargo build --bins` will build all
8668 binaries.
8669- [Added support for haiku][cargo/3952]
8670
8671Misc
8672----
8673
8674- [rustdoc can now use pulldown-cmark with the `--enable-commonmark` flag][40338]
8675- [Rust now uses the official cross compiler for NetBSD][40612]
8676- [rustdoc now accepts `#` at the start of files][40828]
8677- [Fixed jemalloc support for musl][41168]
8678
8679Compatibility Notes
8680-------------------
8681
8682- [Changes to how the `0` flag works in format!][40241] Padding zeroes are now
8683 always placed after the sign if it exists and before the digits. With the `#`
8684 flag the zeroes are placed after the prefix and before the digits.
8685- [Due to the struct field optimisation][40377], using `transmute` on structs
8686 that have no `repr` attribute or `#[repr(Rust)]` will no longer work. This has
8687 always been undefined behavior, but is now more likely to break in practice.
8688- [The refactor of trait object type parsing][40043] fixed a bug where `+` was
8689 receiving the wrong priority parsing things like `&for<'a> Tr<'a> + Send` as
8690 `&(for<'a> Tr<'a> + Send)` instead of `(&for<'a> Tr<'a>) + Send`
8691- [Overlapping inherent `impl`s are now a hard error][40728]
8692- [`PartialOrd` and `Ord` must agree on the ordering.][41270]
8693- [`rustc main.rs -o out --emit=asm,llvm-ir`][41085] Now will output
8694 `out.asm` and `out.ll` instead of only one of the filetypes.
8695- [ calling a function that returns `Self` will no longer work][41805] when
8696 the size of `Self` cannot be statically determined.
8697- [rustc now builds with a "pthreads" flavour of MinGW for Windows GNU][40805]
8698 this has caused a few regressions namely:
8699
8700 - Changed the link order of local static/dynamic libraries (respecting the
8701 order on given rather than having the compiler reorder).
8702 - Changed how MinGW is linked, native code linked to dynamic libraries
8703 may require manually linking to the gcc support library (for the native
8704 code itself)
8705
8706[38165]: https://github.com/rust-lang/rust/pull/38165
8707[39799]: https://github.com/rust-lang/rust/pull/39799
8708[39891]: https://github.com/rust-lang/rust/pull/39891
8709[40043]: https://github.com/rust-lang/rust/pull/40043
8710[40241]: https://github.com/rust-lang/rust/pull/40241
8711[40338]: https://github.com/rust-lang/rust/pull/40338
8712[40367]: https://github.com/rust-lang/rust/pull/40367
8713[40377]: https://github.com/rust-lang/rust/pull/40377
8714[40409]: https://github.com/rust-lang/rust/pull/40409
8715[40516]: https://github.com/rust-lang/rust/pull/40516
8716[40556]: https://github.com/rust-lang/rust/pull/40556
8717[40561]: https://github.com/rust-lang/rust/pull/40561
8718[40589]: https://github.com/rust-lang/rust/pull/40589
8719[40612]: https://github.com/rust-lang/rust/pull/40612
8720[40723]: https://github.com/rust-lang/rust/pull/40723
8721[40728]: https://github.com/rust-lang/rust/pull/40728
8722[40731]: https://github.com/rust-lang/rust/pull/40731
8723[40734]: https://github.com/rust-lang/rust/pull/40734
8724[40805]: https://github.com/rust-lang/rust/pull/40805
8725[40807]: https://github.com/rust-lang/rust/pull/40807
8726[40828]: https://github.com/rust-lang/rust/pull/40828
8727[40870]: https://github.com/rust-lang/rust/pull/40870
8728[41085]: https://github.com/rust-lang/rust/pull/41085
8729[41143]: https://github.com/rust-lang/rust/pull/41143
8730[41168]: https://github.com/rust-lang/rust/pull/41168
8731[41270]: https://github.com/rust-lang/rust/issues/41270
8732[41469]: https://github.com/rust-lang/rust/pull/41469
8733[41805]: https://github.com/rust-lang/rust/issues/41805
8734[RFC 1422]: https://github.com/rust-lang/rfcs/blob/master/text/1422-pub-restricted.md
8735[RFC 1665]: https://github.com/rust-lang/rfcs/blob/master/text/1665-windows-subsystem.md
8736[`Child::try_wait`]: https://doc.rust-lang.org/std/process/struct.Child.html#method.try_wait
8737[`HashMap::retain`]: https://doc.rust-lang.org/std/collections/struct.HashMap.html#method.retain
8738[`HashSet::retain`]: https://doc.rust-lang.org/std/collections/struct.HashSet.html#method.retain
8739[`PeekMut::pop`]: https://doc.rust-lang.org/std/collections/binary_heap/struct.PeekMut.html#method.pop
8740[`TcpStream::peek`]: https://doc.rust-lang.org/std/net/struct.TcpStream.html#method.peek
8741[`UdpSocket::peek_from`]: https://doc.rust-lang.org/std/net/struct.UdpSocket.html#method.peek_from
8742[`UdpSocket::peek`]: https://doc.rust-lang.org/std/net/struct.UdpSocket.html#method.peek
8743[cargo/3842]: https://github.com/rust-lang/cargo/pull/3842
8744[cargo/3847]: https://github.com/rust-lang/cargo/pull/3847
8745[cargo/3885]: https://github.com/rust-lang/cargo/pull/3885
8746[cargo/3901]: https://github.com/rust-lang/cargo/pull/3901
8747[cargo/3952]: https://github.com/rust-lang/cargo/pull/3952
8748
8749
8750Version 1.17.0 (2017-04-27)
8751===========================
8752
8753Language
8754--------
8755
8756* [The lifetime of statics and consts defaults to `'static`][39265]. [RFC 1623]
8757* [Fields of structs may be initialized without duplicating the field/variable
8758 names][39761]. [RFC 1682]
8759* [`Self` may be included in the `where` clause of `impls`][38864]. [RFC 1647]
8760* [When coercing to an unsized type lifetimes must be equal][40319]. That is,
8761 there is no subtyping between `T` and `U` when `T: Unsize<U>`. For example,
8762 coercing `&mut [&'a X; N]` to `&mut [&'b X]` requires `'a` be equal to
8763 `'b`. Soundness fix.
8764* [Values passed to the indexing operator, `[]`, automatically coerce][40166]
8765* [Static variables may contain references to other statics][40027]
8766
8767Compiler
8768--------
8769
8770* [Exit quickly on only `--emit dep-info`][40336]
8771* [Make `-C relocation-model` more correctly determine whether the linker
8772 creates a position-independent executable][40245]
8773* [Add `-C overflow-checks` to directly control whether integer overflow
8774 panics][40037]
8775* [The rustc type checker now checks items on demand instead of in a single
8776 in-order pass][40008]. This is mostly an internal refactoring in support of
8777 future work, including incremental type checking, but also resolves [RFC
8778 1647], allowing `Self` to appear in `impl` `where` clauses.
8779* [Optimize vtable loads][39995]
8780* [Turn off vectorization for Emscripten targets][39990]
8781* [Provide suggestions for unknown macros imported with `use`][39953]
8782* [Fix ICEs in path resolution][39939]
8783* [Strip exception handling code on Emscripten when `panic=abort`][39193]
8784* [Add clearer error message using `&str + &str`][39116]
8785
8786Stabilized APIs
8787---------------
8788
8789* [`Arc::into_raw`]
8790* [`Arc::from_raw`]
8791* [`Arc::ptr_eq`]
8792* [`Rc::into_raw`]
8793* [`Rc::from_raw`]
8794* [`Rc::ptr_eq`]
8795* [`Ordering::then`]
8796* [`Ordering::then_with`]
8797* [`BTreeMap::range`]
8798* [`BTreeMap::range_mut`]
8799* [`collections::Bound`]
8800* [`process::abort`]
8801* [`ptr::read_unaligned`]
8802* [`ptr::write_unaligned`]
8803* [`Result::expect_err`]
8804* [`Cell::swap`]
8805* [`Cell::replace`]
8806* [`Cell::into_inner`]
8807* [`Cell::take`]
8808
8809Libraries
8810---------
8811
8812* [`BTreeMap` and `BTreeSet` can iterate over ranges][27787]
8813* [`Cell` can store non-`Copy` types][39793]. [RFC 1651]
8814* [`String` implements `FromIterator<&char>`][40028]
8815* `Box` [implements][40009] a number of new conversions:
8816 `From<Box<str>> for String`,
8817 `From<Box<[T]>> for Vec<T>`,
8818 `From<Box<CStr>> for CString`,
8819 `From<Box<OsStr>> for OsString`,
8820 `From<Box<Path>> for PathBuf`,
8821 `Into<Box<str>> for String`,
8822 `Into<Box<[T]>> for Vec<T>`,
8823 `Into<Box<CStr>> for CString`,
8824 `Into<Box<OsStr>> for OsString`,
8825 `Into<Box<Path>> for PathBuf`,
8826 `Default for Box<str>`,
8827 `Default for Box<CStr>`,
8828 `Default for Box<OsStr>`,
8829 `From<&CStr> for Box<CStr>`,
8830 `From<&OsStr> for Box<OsStr>`,
8831 `From<&Path> for Box<Path>`
8832* [`ffi::FromBytesWithNulError` implements `Error` and `Display`][39960]
8833* [Specialize `PartialOrd<A> for [A] where A: Ord`][39642]
8834* [Slightly optimize `slice::sort`][39538]
8835* [Add `ToString` trait specialization for `Cow<'a, str>` and `String`][39440]
8836* [`Box<[T]>` implements `From<&[T]> where T: Copy`,
8837 `Box<str>` implements `From<&str>`][39438]
8838* [`IpAddr` implements `From` for various arrays. `SocketAddr` implements
8839 `From<(I, u16)> where I: Into<IpAddr>`][39372]
8840* [`format!` estimates the needed capacity before writing a string][39356]
8841* [Support unprivileged symlink creation in Windows][38921]
8842* [`PathBuf` implements `Default`][38764]
8843* [Implement `PartialEq<[A]>` for `VecDeque<A>`][38661]
8844* [`HashMap` resizes adaptively][38368] to guard against DOS attacks
8845 and poor hash functions.
8846
8847Cargo
8848-----
8849
8850* [Add `cargo check --all`][cargo/3731]
8851* [Add an option to ignore SSL revocation checking][cargo/3699]
8852* [Add `cargo run --package`][cargo/3691]
8853* [Add `required_features`][cargo/3667]
8854* [Assume `build.rs` is a build script][cargo/3664]
8855* [Find workspace via `workspace_root` link in containing member][cargo/3562]
8856
8857Misc
8858----
8859
8860* [Documentation is rendered with mdbook instead of the obsolete, in-tree
8861 `rustbook`][39633]
8862* [The "Unstable Book" documents nightly-only features][ubook]
8863* [Improve the style of the sidebar in rustdoc output][40265]
8864* [Configure build correctly on 64-bit CPU's with the armhf ABI][40261]
8865* [Fix MSP430 breakage due to `i128`][40257]
8866* [Preliminary Solaris/SPARCv9 support][39903]
8867* [`rustc` is linked statically on Windows MSVC targets][39837], allowing it to
8868 run without installing the MSVC runtime.
8869* [`rustdoc --test` includes file names in test names][39788]
8870* This release includes builds of `std` for `sparc64-unknown-linux-gnu`,
8871 `aarch64-unknown-linux-fuchsia`, and `x86_64-unknown-linux-fuchsia`.
8872* [Initial support for `aarch64-unknown-freebsd`][39491]
8873* [Initial support for `i686-unknown-netbsd`][39426]
8874* [This release no longer includes the old makefile build system][39431]. Rust
8875 is built with a custom build system, written in Rust, and with Cargo.
8876* [Add Debug implementations for libcollection structs][39002]
8877* [`TypeId` implements `PartialOrd` and `Ord`][38981]
8878* [`--test-threads=0` produces an error][38945]
8879* [`rustup` installs documentation by default][40526]
8880* [The Rust source includes NatVis visualizations][39843]. These can be used by
8881 WinDbg and Visual Studio to improve the debugging experience.
8882
8883Compatibility Notes
8884-------------------
8885
8886* [Rust 1.17 does not correctly detect the MSVC 2017 linker][38584]. As a
8887 workaround, either use MSVC 2015 or run vcvars.bat.
8888* [When coercing to an unsized type lifetimes must be equal][40319]. That is,
8889 disallow subtyping between `T` and `U` when `T: Unsize<U>`, e.g. coercing
8890 `&mut [&'a X; N]` to `&mut [&'b X]` requires `'a` be equal to `'b`. Soundness
8891 fix.
8892* [`format!` and `Display::to_string` panic if an underlying formatting
8893 implementation returns an error][40117]. Previously the error was silently
8894 ignored. It is incorrect for `write_fmt` to return an error when writing
8895 to a string.
8896* [In-tree crates are verified to be unstable][39851]. Previously, some minor
8897 crates were marked stable and could be accessed from the stable toolchain.
8898* [Rust git source no longer includes vendored crates][39728]. Those that need
8899 to build with vendored crates should build from release tarballs.
8900* [Fix inert attributes from `proc_macro_derives`][39572]
8901* [During crate resolution, rustc prefers a crate in the sysroot if two crates
8902 are otherwise identical][39518]. Unlikely to be encountered outside the Rust
8903 build system.
8904* [Fixed bugs around how type inference interacts with dead-code][39485]. The
8905 existing code generally ignores the type of dead-code unless a type-hint is
8906 provided; this can cause surprising inference interactions particularly around
8907 defaulting. The new code uniformly ignores the result type of dead-code.
8908* [Tuple-struct constructors with private fields are no longer visible][38932]
8909* [Lifetime parameters that do not appear in the arguments are now considered
8910 early-bound][38897], resolving a soundness bug (#[32330]). The
8911 `hr_lifetime_in_assoc_type` future-compatibility lint has been in effect since
8912 April of 2016.
8913* [rustdoc: fix doctests with non-feature crate attributes][38161]
8914* [Make transmuting from fn item types to pointer-sized types a hard
8915 error][34198]
8916
8917[27787]: https://github.com/rust-lang/rust/issues/27787
8918[32330]: https://github.com/rust-lang/rust/issues/32330
8919[34198]: https://github.com/rust-lang/rust/pull/34198
8920[38161]: https://github.com/rust-lang/rust/pull/38161
8921[38368]: https://github.com/rust-lang/rust/pull/38368
8922[38584]: https://github.com/rust-lang/rust/issues/38584
8923[38661]: https://github.com/rust-lang/rust/pull/38661
8924[38764]: https://github.com/rust-lang/rust/pull/38764
8925[38864]: https://github.com/rust-lang/rust/issues/38864
8926[38897]: https://github.com/rust-lang/rust/pull/38897
8927[38921]: https://github.com/rust-lang/rust/pull/38921
8928[38932]: https://github.com/rust-lang/rust/pull/38932
8929[38945]: https://github.com/rust-lang/rust/pull/38945
8930[38981]: https://github.com/rust-lang/rust/pull/38981
8931[39002]: https://github.com/rust-lang/rust/pull/39002
8932[39116]: https://github.com/rust-lang/rust/pull/39116
8933[39193]: https://github.com/rust-lang/rust/pull/39193
8934[39265]: https://github.com/rust-lang/rust/pull/39265
8935[39356]: https://github.com/rust-lang/rust/pull/39356
8936[39372]: https://github.com/rust-lang/rust/pull/39372
8937[39426]: https://github.com/rust-lang/rust/pull/39426
8938[39431]: https://github.com/rust-lang/rust/pull/39431
8939[39438]: https://github.com/rust-lang/rust/pull/39438
8940[39440]: https://github.com/rust-lang/rust/pull/39440
8941[39485]: https://github.com/rust-lang/rust/pull/39485
8942[39491]: https://github.com/rust-lang/rust/pull/39491
8943[39518]: https://github.com/rust-lang/rust/pull/39518
8944[39538]: https://github.com/rust-lang/rust/pull/39538
8945[39572]: https://github.com/rust-lang/rust/pull/39572
8946[39633]: https://github.com/rust-lang/rust/pull/39633
8947[39642]: https://github.com/rust-lang/rust/pull/39642
8948[39728]: https://github.com/rust-lang/rust/pull/39728
8949[39761]: https://github.com/rust-lang/rust/pull/39761
8950[39788]: https://github.com/rust-lang/rust/pull/39788
8951[39793]: https://github.com/rust-lang/rust/pull/39793
8952[39837]: https://github.com/rust-lang/rust/pull/39837
8953[39843]: https://github.com/rust-lang/rust/pull/39843
8954[39851]: https://github.com/rust-lang/rust/pull/39851
8955[39903]: https://github.com/rust-lang/rust/pull/39903
8956[39939]: https://github.com/rust-lang/rust/pull/39939
8957[39953]: https://github.com/rust-lang/rust/pull/39953
8958[39960]: https://github.com/rust-lang/rust/pull/39960
8959[39990]: https://github.com/rust-lang/rust/pull/39990
8960[39995]: https://github.com/rust-lang/rust/pull/39995
8961[40008]: https://github.com/rust-lang/rust/pull/40008
8962[40009]: https://github.com/rust-lang/rust/pull/40009
8963[40027]: https://github.com/rust-lang/rust/pull/40027
8964[40028]: https://github.com/rust-lang/rust/pull/40028
8965[40037]: https://github.com/rust-lang/rust/pull/40037
8966[40117]: https://github.com/rust-lang/rust/pull/40117
8967[40166]: https://github.com/rust-lang/rust/pull/40166
8968[40245]: https://github.com/rust-lang/rust/pull/40245
8969[40257]: https://github.com/rust-lang/rust/pull/40257
8970[40261]: https://github.com/rust-lang/rust/pull/40261
8971[40265]: https://github.com/rust-lang/rust/pull/40265
8972[40319]: https://github.com/rust-lang/rust/pull/40319
8973[40336]: https://github.com/rust-lang/rust/pull/40336
8974[40526]: https://github.com/rust-lang/rust/pull/40526
8975[RFC 1623]: https://github.com/rust-lang/rfcs/blob/master/text/1623-static.md
8976[RFC 1647]: https://github.com/rust-lang/rfcs/blob/master/text/1647-allow-self-in-where-clauses.md
8977[RFC 1651]: https://github.com/rust-lang/rfcs/blob/master/text/1651-movecell.md
8978[RFC 1682]: https://github.com/rust-lang/rfcs/blob/master/text/1682-field-init-shorthand.md
8979[`Arc::from_raw`]: https://doc.rust-lang.org/std/sync/struct.Arc.html#method.from_raw
8980[`Arc::into_raw`]: https://doc.rust-lang.org/std/sync/struct.Arc.html#method.into_raw
8981[`Arc::ptr_eq`]: https://doc.rust-lang.org/std/sync/struct.Arc.html#method.ptr_eq
8982[`BTreeMap::range_mut`]: https://doc.rust-lang.org/std/collections/btree_map/struct.BTreeMap.html#method.range_mut
8983[`BTreeMap::range`]: https://doc.rust-lang.org/std/collections/btree_map/struct.BTreeMap.html#method.range
8984[`Cell::into_inner`]: https://doc.rust-lang.org/std/cell/struct.Cell.html#method.into_inner
8985[`Cell::replace`]: https://doc.rust-lang.org/std/cell/struct.Cell.html#method.replace
8986[`Cell::swap`]: https://doc.rust-lang.org/std/cell/struct.Cell.html#method.swap
8987[`Cell::take`]: https://doc.rust-lang.org/std/cell/struct.Cell.html#method.take
8988[`Ordering::then_with`]: https://doc.rust-lang.org/std/cmp/enum.Ordering.html#method.then_with
8989[`Ordering::then`]: https://doc.rust-lang.org/std/cmp/enum.Ordering.html#method.then
8990[`Rc::from_raw`]: https://doc.rust-lang.org/std/rc/struct.Rc.html#method.from_raw
8991[`Rc::into_raw`]: https://doc.rust-lang.org/std/rc/struct.Rc.html#method.into_raw
8992[`Rc::ptr_eq`]: https://doc.rust-lang.org/std/rc/struct.Rc.html#method.ptr_eq
8993[`Result::expect_err`]: https://doc.rust-lang.org/std/result/enum.Result.html#method.expect_err
8994[`collections::Bound`]: https://doc.rust-lang.org/std/collections/enum.Bound.html
8995[`process::abort`]: https://doc.rust-lang.org/std/process/fn.abort.html
8996[`ptr::read_unaligned`]: https://doc.rust-lang.org/std/ptr/fn.read_unaligned.html
8997[`ptr::write_unaligned`]: https://doc.rust-lang.org/std/ptr/fn.write_unaligned.html
8998[cargo/3562]: https://github.com/rust-lang/cargo/pull/3562
8999[cargo/3664]: https://github.com/rust-lang/cargo/pull/3664
9000[cargo/3667]: https://github.com/rust-lang/cargo/pull/3667
9001[cargo/3691]: https://github.com/rust-lang/cargo/pull/3691
9002[cargo/3699]: https://github.com/rust-lang/cargo/pull/3699
9003[cargo/3731]: https://github.com/rust-lang/cargo/pull/3731
9004[ubook]: https://doc.rust-lang.org/unstable-book/
9005
9006
9007Version 1.16.0 (2017-03-16)
9008===========================
9009
9010Language
9011--------
9012
9013* [The compiler's `dead_code` lint now accounts for type aliases][38051].
9014* [Uninhabitable enums (those without any variants) no longer permit wildcard
9015 match patterns][38069]
9016* [Clean up semantics of `self` in an import list][38313]
9017* [`Self` may appear in `impl` headers][38920]
9018* [`Self` may appear in struct expressions][39282]
9019
9020Compiler
9021--------
9022
9023* [`rustc` now supports `--emit=metadata`, which causes rustc to emit
9024 a `.rmeta` file containing only crate metadata][38571]. This can be
9025 used by tools like the Rust Language Service to perform
9026 metadata-only builds.
9027* [Levenshtein based typo suggestions now work in most places, while
9028 previously they worked only for fields and sometimes for local
9029 variables][38927]. Together with the overhaul of "no
9030 resolution"/"unexpected resolution" errors (#[38154]) they result in
9031 large and systematic improvement in resolution diagnostics.
9032* [Fix `transmute::<T, U>` where `T` requires a bigger alignment than
9033 `U`][38670]
9034* [rustc: use -Xlinker when specifying an rpath with ',' in it][38798]
9035* [`rustc` no longer attempts to provide "consider using an explicit
9036 lifetime" suggestions][37057]. They were inaccurate.
9037
9038Stabilized APIs
9039---------------
9040
9041* [`VecDeque::truncate`]
9042* [`VecDeque::resize`]
9043* [`String::insert_str`]
9044* [`Duration::checked_add`]
9045* [`Duration::checked_sub`]
9046* [`Duration::checked_div`]
9047* [`Duration::checked_mul`]
9048* [`str::replacen`]
9049* [`str::repeat`]
9050* [`SocketAddr::is_ipv4`]
9051* [`SocketAddr::is_ipv6`]
9052* [`IpAddr::is_ipv4`]
9053* [`IpAddr::is_ipv6`]
9054* [`Vec::dedup_by`]
9055* [`Vec::dedup_by_key`]
9056* [`Result::unwrap_or_default`]
9057* [`<*const T>::wrapping_offset`]
9058* [`<*mut T>::wrapping_offset`]
9059* `CommandExt::creation_flags`
9060* [`File::set_permissions`]
9061* [`String::split_off`]
9062
9063Libraries
9064---------
9065
9066* [`[T]::binary_search` and `[T]::binary_search_by_key` now take
9067 their argument by `Borrow` parameter][37761]
9068* [All public types in std implement `Debug`][38006]
9069* [`IpAddr` implements `From<Ipv4Addr>` and `From<Ipv6Addr>`][38327]
9070* [`Ipv6Addr` implements `From<[u16; 8]>`][38131]
9071* [Ctrl-Z returns from `Stdin.read()` when reading from the console on
9072 Windows][38274]
9073* [std: Fix partial writes in `LineWriter`][38062]
9074* [std: Clamp max read/write sizes on Unix][38622]
9075* [Use more specific panic message for `&str` slicing errors][38066]
9076* [`TcpListener::set_only_v6` is deprecated][38304]. This
9077 functionality cannot be achieved in std currently.
9078* [`writeln!`, like `println!`, now accepts a form with no string
9079 or formatting arguments, to just print a newline][38469]
9080* [Implement `iter::Sum` and `iter::Product` for `Result`][38580]
9081* [Reduce the size of static data in `std_unicode::tables`][38781]
9082* [`char::EscapeDebug`, `EscapeDefault`, `EscapeUnicode`,
9083 `CaseMappingIter`, `ToLowercase`, `ToUppercase`, implement
9084 `Display`][38909]
9085* [`Duration` implements `Sum`][38712]
9086* [`String` implements `ToSocketAddrs`][39048]
9087
9088Cargo
9089-----
9090
9091* [The `cargo check` command does a type check of a project without
9092 building it][cargo/3296]
9093* [crates.io will display CI badges from Travis and AppVeyor, if
9094 specified in Cargo.toml][cargo/3546]
9095* [crates.io will display categories listed in Cargo.toml][cargo/3301]
9096* [Compilation profiles accept integer values for `debug`, in addition
9097 to `true` and `false`. These are passed to `rustc` as the value to
9098 `-C debuginfo`][cargo/3534]
9099* [Implement `cargo --version --verbose`][cargo/3604]
9100* [All builds now output 'dep-info' build dependencies compatible with
9101 make and ninja][cargo/3557]
9102* [Build all workspace members with `build --all`][cargo/3511]
9103* [Document all workspace members with `doc --all`][cargo/3515]
9104* [Path deps outside workspace are not members][cargo/3443]
9105
9106Misc
9107----
9108
9109* [`rustdoc` has a `--sysroot` argument that, like `rustc`, specifies
9110 the path to the Rust implementation][38589]
9111* [The `armv7-linux-androideabi` target no longer enables NEON
9112 extensions, per Google's ABI guide][38413]
9113* [The stock standard library can be compiled for Redox OS][38401]
9114* [Rust has initial SPARC support][38726]. Tier 3. No builds
9115 available.
9116* [Rust has experimental support for Nvidia PTX][38559]. Tier 3. No
9117 builds available.
9118* [Fix backtraces on i686-pc-windows-gnu by disabling FPO][39379]
9119
9120Compatibility Notes
9121-------------------
9122
9123* [Uninhabitable enums (those without any variants) no longer permit wildcard
9124 match patterns][38069]
9125* In this release, references to uninhabited types can not be
9126 pattern-matched. This was accidentally allowed in 1.15.
9127* [The compiler's `dead_code` lint now accounts for type aliases][38051].
9128* [Ctrl-Z returns from `Stdin.read()` when reading from the console on
9129 Windows][38274]
9130* [Clean up semantics of `self` in an import list][38313]
9131* Reimplemented lifetime elision. This change was almost entirely compatible
9132 with existing code, but it did close a number of small bugs and loopholes,
9133 as well as being more accepting in some other [cases][41105].
9134
9135[37057]: https://github.com/rust-lang/rust/pull/37057
9136[37761]: https://github.com/rust-lang/rust/pull/37761
9137[38006]: https://github.com/rust-lang/rust/pull/38006
9138[38051]: https://github.com/rust-lang/rust/pull/38051
9139[38062]: https://github.com/rust-lang/rust/pull/38062
9140[38622]: https://github.com/rust-lang/rust/pull/38622
9141[38066]: https://github.com/rust-lang/rust/pull/38066
9142[38069]: https://github.com/rust-lang/rust/pull/38069
9143[38131]: https://github.com/rust-lang/rust/pull/38131
9144[38154]: https://github.com/rust-lang/rust/pull/38154
9145[38274]: https://github.com/rust-lang/rust/pull/38274
9146[38304]: https://github.com/rust-lang/rust/pull/38304
9147[38313]: https://github.com/rust-lang/rust/pull/38313
9148[38327]: https://github.com/rust-lang/rust/pull/38327
9149[38401]: https://github.com/rust-lang/rust/pull/38401
9150[38413]: https://github.com/rust-lang/rust/pull/38413
9151[38469]: https://github.com/rust-lang/rust/pull/38469
9152[38559]: https://github.com/rust-lang/rust/pull/38559
9153[38571]: https://github.com/rust-lang/rust/pull/38571
9154[38580]: https://github.com/rust-lang/rust/pull/38580
9155[38589]: https://github.com/rust-lang/rust/pull/38589
9156[38670]: https://github.com/rust-lang/rust/pull/38670
9157[38712]: https://github.com/rust-lang/rust/pull/38712
9158[38726]: https://github.com/rust-lang/rust/pull/38726
9159[38781]: https://github.com/rust-lang/rust/pull/38781
9160[38798]: https://github.com/rust-lang/rust/pull/38798
9161[38909]: https://github.com/rust-lang/rust/pull/38909
9162[38920]: https://github.com/rust-lang/rust/pull/38920
9163[38927]: https://github.com/rust-lang/rust/pull/38927
9164[39048]: https://github.com/rust-lang/rust/pull/39048
9165[39282]: https://github.com/rust-lang/rust/pull/39282
9166[39379]: https://github.com/rust-lang/rust/pull/39379
9167[41105]: https://github.com/rust-lang/rust/issues/41105
9168[`<*const T>::wrapping_offset`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.wrapping_offset
9169[`<*mut T>::wrapping_offset`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.wrapping_offset-1
9170[`Duration::checked_add`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.checked_add
9171[`Duration::checked_div`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.checked_div
9172[`Duration::checked_mul`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.checked_mul
9173[`Duration::checked_sub`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.checked_sub
9174[`File::set_permissions`]: https://doc.rust-lang.org/std/fs/struct.File.html#method.set_permissions
9175[`IpAddr::is_ipv4`]: https://doc.rust-lang.org/std/net/enum.IpAddr.html#method.is_ipv4
9176[`IpAddr::is_ipv6`]: https://doc.rust-lang.org/std/net/enum.IpAddr.html#method.is_ipv6
9177[`Result::unwrap_or_default`]: https://doc.rust-lang.org/std/result/enum.Result.html#method.unwrap_or_default
9178[`SocketAddr::is_ipv4`]: https://doc.rust-lang.org/std/net/enum.SocketAddr.html#method.is_ipv4
9179[`SocketAddr::is_ipv6`]: https://doc.rust-lang.org/std/net/enum.SocketAddr.html#method.is_ipv6
9180[`String::insert_str`]: https://doc.rust-lang.org/std/string/struct.String.html#method.insert_str
9181[`String::split_off`]: https://doc.rust-lang.org/std/string/struct.String.html#method.split_off
9182[`Vec::dedup_by_key`]: https://doc.rust-lang.org/std/vec/struct.Vec.html#method.dedup_by_key
9183[`Vec::dedup_by`]: https://doc.rust-lang.org/std/vec/struct.Vec.html#method.dedup_by
9184[`VecDeque::resize`]: https://doc.rust-lang.org/std/collections/vec_deque/struct.VecDeque.html#method.resize
9185[`VecDeque::truncate`]: https://doc.rust-lang.org/std/collections/vec_deque/struct.VecDeque.html#method.truncate
9186[`str::repeat`]: https://doc.rust-lang.org/std/primitive.str.html#method.repeat
9187[`str::replacen`]: https://doc.rust-lang.org/std/primitive.str.html#method.replacen
9188[cargo/3296]: https://github.com/rust-lang/cargo/pull/3296
9189[cargo/3301]: https://github.com/rust-lang/cargo/pull/3301
9190[cargo/3443]: https://github.com/rust-lang/cargo/pull/3443
9191[cargo/3511]: https://github.com/rust-lang/cargo/pull/3511
9192[cargo/3515]: https://github.com/rust-lang/cargo/pull/3515
9193[cargo/3534]: https://github.com/rust-lang/cargo/pull/3534
9194[cargo/3546]: https://github.com/rust-lang/cargo/pull/3546
9195[cargo/3557]: https://github.com/rust-lang/cargo/pull/3557
9196[cargo/3604]: https://github.com/rust-lang/cargo/pull/3604
9197
9198
9199Version 1.15.1 (2017-02-09)
9200===========================
9201
9202* [Fix IntoIter::as_mut_slice's signature][39466]
9203* [Compile compiler builtins with `-fPIC` on 32-bit platforms][39523]
9204
9205[39466]: https://github.com/rust-lang/rust/pull/39466
9206[39523]: https://github.com/rust-lang/rust/pull/39523
9207
9208
9209Version 1.15.0 (2017-02-02)
9210===========================
9211
9212Language
9213--------
9214
9215* Basic procedural macros allowing custom `#[derive]`, aka "macros 1.1", are
9216 stable. This allows popular code-generating crates like Serde and Diesel to
9217 work ergonomically. [RFC 1681].
9218* [Tuple structs may be empty. Unary and empty tuple structs may be instantiated
9219 with curly braces][36868]. Part of [RFC 1506].
9220* [A number of minor changes to name resolution have been activated][37127].
9221 They add up to more consistent semantics, allowing for future evolution of
9222 Rust macros. Specified in [RFC 1560], see its section on ["changes"] for
9223 details of what is different. The breaking changes here have been transitioned
9224 through the [`legacy_imports`] lint since 1.14, with no known regressions.
9225* [In `macro_rules`, `path` fragments can now be parsed as type parameter
9226 bounds][38279]
9227* [`?Sized` can be used in `where` clauses][37791]
9228* [There is now a limit on the size of monomorphized types and it can be
9229 modified with the `#![type_size_limit]` crate attribute, similarly to
9230 the `#![recursion_limit]` attribute][37789]
9231
9232Compiler
9233--------
9234
9235* [On Windows, the compiler will apply dllimport attributes when linking to
9236 extern functions][37973]. Additional attributes and flags can control which
9237 library kind is linked and its name. [RFC 1717].
9238* [Rust-ABI symbols are no longer exported from cdylibs][38117]
9239* [The `--test` flag works with procedural macro crates][38107]
9240* [Fix `extern "aapcs" fn` ABI][37814]
9241* [The `-C no-stack-check` flag is deprecated][37636]. It does nothing.
9242* [The `format!` expander recognizes incorrect `printf` and shell-style
9243 formatting directives and suggests the correct format][37613].
9244* [Only report one error for all unused imports in an import list][37456]
9245
9246Compiler Performance
9247--------------------
9248
9249* [Avoid unnecessary `mk_ty` calls in `Ty::super_fold_with`][37705]
9250* [Avoid more unnecessary `mk_ty` calls in `Ty::super_fold_with`][37979]
9251* [Don't clone in `UnificationTable::probe`][37848]
9252* [Remove `scope_auxiliary` to cut RSS by 10%][37764]
9253* [Use small vectors in type walker][37760]
9254* [Macro expansion performance was improved][37701]
9255* [Change `HirVec<P<T>>` to `HirVec<T>` in `hir::Expr`][37642]
9256* [Replace FNV with a faster hash function][37229]
9257
9258Stabilized APIs
9259---------------
9260
9261* [`std::iter::Iterator::min_by`]
9262* [`std::iter::Iterator::max_by`]
9263* [`std::os::*::fs::FileExt`]
9264* [`std::sync::atomic::Atomic*::get_mut`]
9265* [`std::sync::atomic::Atomic*::into_inner`]
9266* [`std::vec::IntoIter::as_slice`]
9267* [`std::vec::IntoIter::as_mut_slice`]
9268* [`std::sync::mpsc::Receiver::try_iter`]
9269* [`std::os::unix::process::CommandExt::before_exec`]
9270* [`std::rc::Rc::strong_count`]
9271* [`std::rc::Rc::weak_count`]
9272* [`std::sync::Arc::strong_count`]
9273* [`std::sync::Arc::weak_count`]
9274* [`std::char::encode_utf8`]
9275* [`std::char::encode_utf16`]
9276* [`std::cell::Ref::clone`]
9277* [`std::io::Take::into_inner`]
9278
9279Libraries
9280---------
9281
9282* [The standard sorting algorithm has been rewritten for dramatic performance
9283 improvements][38192]. It is a hybrid merge sort, drawing influences from
9284 Timsort. Previously it was a naive merge sort.
9285* [`Iterator::nth` no longer has a `Sized` bound][38134]
9286* [`Extend<&T>` is specialized for `Vec` where `T: Copy`][38182] to improve
9287 performance.
9288* [`chars().count()` is much faster][37888] and so are [`chars().last()`
9289 and `char_indices().last()`][37882]
9290* [Fix ARM Objective-C ABI in `std::env::args`][38146]
9291* [Chinese characters display correctly in `fmt::Debug`][37855]
9292* [Derive `Default` for `Duration`][37699]
9293* [Support creation of anonymous pipes on WinXP/2k][37677]
9294* [`mpsc::RecvTimeoutError` implements `Error`][37527]
9295* [Don't pass overlapped handles to processes][38835]
9296
9297Cargo
9298-----
9299
9300* [In this release, Cargo build scripts no longer have access to the `OUT_DIR`
9301 environment variable at build time via `env!("OUT_DIR")`][cargo/3368]. They
9302 should instead check the variable at runtime with `std::env`. That the value
9303 was set at build time was a bug, and incorrect when cross-compiling. This
9304 change is known to cause breakage.
9305* [Add `--all` flag to `cargo test`][cargo/3221]
9306* [Compile statically against the MSVC CRT][cargo/3363]
9307* [Mix feature flags into fingerprint/metadata shorthash][cargo/3102]
9308* [Link OpenSSL statically on OSX][cargo/3311]
9309* [Apply new fingerprinting to build dir outputs][cargo/3310]
9310* [Test for bad path overrides with summaries][cargo/3336]
9311* [Require `cargo install --vers` to take a semver version][cargo/3338]
9312* [Fix retrying crate downloads for network errors][cargo/3348]
9313* [Implement string lookup for `build.rustflags` config key][cargo/3356]
9314* [Emit more info on --message-format=json][cargo/3319]
9315* [Assume `build.rs` in the same directory as `Cargo.toml` is a build script][cargo/3361]
9316* [Don't ignore errors in workspace manifest][cargo/3409]
9317* [Fix `--message-format JSON` when rustc emits non-JSON warnings][cargo/3410]
9318
9319Tooling
9320-------
9321
9322* [Test runners (binaries built with `--test`) now support a `--list` argument
9323 that lists the tests it contains][38185]
9324* [Test runners now support a `--exact` argument that makes the test filter
9325 match exactly, instead of matching only a substring of the test name][38181]
9326* [rustdoc supports a `--playground-url` flag][37763]
9327* [rustdoc provides more details about `#[should_panic]` errors][37749]
9328
9329Misc
9330----
9331
9332* [The Rust build system is now written in Rust][37817]. The Makefiles may
9333 continue to be used in this release by passing `--disable-rustbuild` to the
9334 configure script, but they will be deleted soon. Note that the new build
9335 system uses a different on-disk layout that will likely affect any scripts
9336 building Rust.
9337* [Rust supports i686-unknown-openbsd][38086]. Tier 3 support. No testing or
9338 releases.
9339* [Rust supports the MSP430][37627]. Tier 3 support. No testing or releases.
9340* [Rust supports the ARMv5TE architecture][37615]. Tier 3 support. No testing or
9341 releases.
9342
9343Compatibility Notes
9344-------------------
9345
9346* [A number of minor changes to name resolution have been activated][37127].
9347 They add up to more consistent semantics, allowing for future evolution of
9348 Rust macros. Specified in [RFC 1560], see its section on ["changes"] for
9349 details of what is different. The breaking changes here have been transitioned
9350 through the [`legacy_imports`] lint since 1.14, with no known regressions.
9351* [In this release, Cargo build scripts no longer have access to the `OUT_DIR`
9352 environment variable at build time via `env!("OUT_DIR")`][cargo/3368]. They
9353 should instead check the variable at runtime with `std::env`. That the value
9354 was set at build time was a bug, and incorrect when cross-compiling. This
9355 change is known to cause breakage.
9356* [Higher-ranked lifetimes are no longer allowed to appear _only_ in associated
9357 types][33685]. The [`hr_lifetime_in_assoc_type` lint] has been a warning since
9358 1.10 and is now an error by default. It will become a hard error in the near
9359 future.
9360* [The semantics relating modules to file system directories are changing in
9361 minor ways][37602]. This is captured in the new `legacy_directory_ownership`
9362 lint, which is a warning in this release, and will become a hard error in the
9363 future.
9364* [Rust-ABI symbols are no longer exported from cdylibs][38117]
9365* [Once `Peekable` peeks a `None` it will return that `None` without re-querying
9366 the underlying iterator][37834]
9367
9368["changes"]: https://github.com/rust-lang/rfcs/blob/master/text/1560-name-resolution.md#changes-to-name-resolution-rules
9369[33685]: https://github.com/rust-lang/rust/issues/33685
9370[36868]: https://github.com/rust-lang/rust/pull/36868
9371[37127]: https://github.com/rust-lang/rust/pull/37127
9372[37229]: https://github.com/rust-lang/rust/pull/37229
9373[37456]: https://github.com/rust-lang/rust/pull/37456
9374[37527]: https://github.com/rust-lang/rust/pull/37527
9375[37602]: https://github.com/rust-lang/rust/pull/37602
9376[37613]: https://github.com/rust-lang/rust/pull/37613
9377[37615]: https://github.com/rust-lang/rust/pull/37615
9378[37636]: https://github.com/rust-lang/rust/pull/37636
9379[37627]: https://github.com/rust-lang/rust/pull/37627
9380[37642]: https://github.com/rust-lang/rust/pull/37642
9381[37677]: https://github.com/rust-lang/rust/pull/37677
9382[37699]: https://github.com/rust-lang/rust/pull/37699
9383[37701]: https://github.com/rust-lang/rust/pull/37701
9384[37705]: https://github.com/rust-lang/rust/pull/37705
9385[37749]: https://github.com/rust-lang/rust/pull/37749
9386[37760]: https://github.com/rust-lang/rust/pull/37760
9387[37763]: https://github.com/rust-lang/rust/pull/37763
9388[37764]: https://github.com/rust-lang/rust/pull/37764
9389[37789]: https://github.com/rust-lang/rust/pull/37789
9390[37791]: https://github.com/rust-lang/rust/pull/37791
9391[37814]: https://github.com/rust-lang/rust/pull/37814
9392[37817]: https://github.com/rust-lang/rust/pull/37817
9393[37834]: https://github.com/rust-lang/rust/pull/37834
9394[37848]: https://github.com/rust-lang/rust/pull/37848
9395[37855]: https://github.com/rust-lang/rust/pull/37855
9396[37882]: https://github.com/rust-lang/rust/pull/37882
9397[37888]: https://github.com/rust-lang/rust/pull/37888
9398[37973]: https://github.com/rust-lang/rust/pull/37973
9399[37979]: https://github.com/rust-lang/rust/pull/37979
9400[38086]: https://github.com/rust-lang/rust/pull/38086
9401[38107]: https://github.com/rust-lang/rust/pull/38107
9402[38117]: https://github.com/rust-lang/rust/pull/38117
9403[38134]: https://github.com/rust-lang/rust/pull/38134
9404[38146]: https://github.com/rust-lang/rust/pull/38146
9405[38181]: https://github.com/rust-lang/rust/pull/38181
9406[38182]: https://github.com/rust-lang/rust/pull/38182
9407[38185]: https://github.com/rust-lang/rust/pull/38185
9408[38192]: https://github.com/rust-lang/rust/pull/38192
9409[38279]: https://github.com/rust-lang/rust/pull/38279
9410[38835]: https://github.com/rust-lang/rust/pull/38835
9411[RFC 1506]: https://github.com/rust-lang/rfcs/blob/master/text/1506-adt-kinds.md
9412[RFC 1560]: https://github.com/rust-lang/rfcs/blob/master/text/1560-name-resolution.md
9413[RFC 1681]: https://github.com/rust-lang/rfcs/blob/master/text/1681-macros-1.1.md
9414[RFC 1717]: https://github.com/rust-lang/rfcs/blob/master/text/1717-dllimport.md
9415[`hr_lifetime_in_assoc_type` lint]: https://github.com/rust-lang/rust/issues/33685
9416[`legacy_imports`]: https://github.com/rust-lang/rust/pull/38271
9417[cargo/3102]: https://github.com/rust-lang/cargo/pull/3102
9418[cargo/3221]: https://github.com/rust-lang/cargo/pull/3221
9419[cargo/3310]: https://github.com/rust-lang/cargo/pull/3310
9420[cargo/3311]: https://github.com/rust-lang/cargo/pull/3311
9421[cargo/3319]: https://github.com/rust-lang/cargo/pull/3319
9422[cargo/3336]: https://github.com/rust-lang/cargo/pull/3336
9423[cargo/3338]: https://github.com/rust-lang/cargo/pull/3338
9424[cargo/3348]: https://github.com/rust-lang/cargo/pull/3348
9425[cargo/3356]: https://github.com/rust-lang/cargo/pull/3356
9426[cargo/3361]: https://github.com/rust-lang/cargo/pull/3361
9427[cargo/3363]: https://github.com/rust-lang/cargo/pull/3363
9428[cargo/3368]: https://github.com/rust-lang/cargo/issues/3368
9429[cargo/3409]: https://github.com/rust-lang/cargo/pull/3409
9430[cargo/3410]: https://github.com/rust-lang/cargo/pull/3410
9431[`std::iter::Iterator::min_by`]: https://doc.rust-lang.org/std/iter/trait.Iterator.html#method.min_by
9432[`std::iter::Iterator::max_by`]: https://doc.rust-lang.org/std/iter/trait.Iterator.html#method.max_by
9433[`std::os::*::fs::FileExt`]: https://doc.rust-lang.org/std/os/unix/fs/trait.FileExt.html
9434[`std::sync::atomic::Atomic*::get_mut`]: https://doc.rust-lang.org/std/sync/atomic/struct.AtomicU8.html#method.get_mut
9435[`std::sync::atomic::Atomic*::into_inner`]: https://doc.rust-lang.org/std/sync/atomic/struct.AtomicU8.html#method.into_inner
9436[`std::vec::IntoIter::as_slice`]: https://doc.rust-lang.org/std/vec/struct.IntoIter.html#method.as_slice
9437[`std::vec::IntoIter::as_mut_slice`]: https://doc.rust-lang.org/std/vec/struct.IntoIter.html#method.as_mut_slice
9438[`std::sync::mpsc::Receiver::try_iter`]: https://doc.rust-lang.org/std/sync/mpsc/struct.Receiver.html#method.try_iter
9439[`std::os::unix::process::CommandExt::before_exec`]: https://doc.rust-lang.org/std/os/unix/process/trait.CommandExt.html#tymethod.before_exec
9440[`std::rc::Rc::strong_count`]: https://doc.rust-lang.org/std/rc/struct.Rc.html#method.strong_count
9441[`std::rc::Rc::weak_count`]: https://doc.rust-lang.org/std/rc/struct.Rc.html#method.weak_count
9442[`std::sync::Arc::strong_count`]: https://doc.rust-lang.org/std/sync/struct.Arc.html#method.strong_count
9443[`std::sync::Arc::weak_count`]: https://doc.rust-lang.org/std/sync/struct.Arc.html#method.weak_count
9444[`std::char::encode_utf8`]: https://doc.rust-lang.org/std/primitive.char.html#method.encode_utf8
9445[`std::char::encode_utf16`]: https://doc.rust-lang.org/std/primitive.char.html#method.encode_utf16
9446[`std::cell::Ref::clone`]: https://doc.rust-lang.org/std/cell/struct.Ref.html#method.clone
9447[`std::io::Take::into_inner`]: https://doc.rust-lang.org/std/io/struct.Take.html#method.into_inner
9448
9449
9450Version 1.14.0 (2016-12-22)
9451===========================
9452
9453Language
9454--------
9455
9456* [`..` matches multiple tuple fields in enum variants, structs
9457 and tuples][36843]. [RFC 1492].
9458* [Safe `fn` items can be coerced to `unsafe fn` pointers][37389]
9459* [`use *` and `use ::*` both glob-import from the crate root][37367]
9460* [It's now possible to call a `Vec<Box<Fn()>>` without explicit
9461 dereferencing][36822]
9462
9463Compiler
9464--------
9465
9466* [Mark enums with non-zero discriminant as non-zero][37224]
9467* [Lower-case `static mut` names are linted like other
9468 statics and consts][37162]
9469* [Fix ICE on some macros in const integer positions
9470 (e.g. `[u8; m!()]`)][36819]
9471* [Improve error message and snippet for "did you mean `x`"][36798]
9472* [Add a panic-strategy field to the target specification][36794]
9473* [Include LLVM version in `--version --verbose`][37200]
9474
9475Compile-time Optimizations
9476--------------------------
9477
9478* [Improve macro expansion performance][37569]
9479* [Shrink `Expr_::ExprInlineAsm`][37445]
9480* [Replace all uses of SHA-256 with BLAKE2b][37439]
9481* [Reduce the number of bytes hashed by `IchHasher`][37427]
9482* [Avoid more allocations when compiling html5ever][37373]
9483* [Use `SmallVector` in `CombineFields::instantiate`][37322]
9484* [Avoid some allocations in the macro parser][37318]
9485* [Use a faster deflate setting][37298]
9486* [Add `ArrayVec` and `AccumulateVec` to reduce heap allocations
9487 during interning of slices][37270]
9488* [Optimize `write_metadata`][37267]
9489* [Don't process obligation forest cycles when stalled][37231]
9490* [Avoid many `CrateConfig` clones][37161]
9491* [Optimize `Substs::super_fold_with`][37108]
9492* [Optimize `ObligationForest`'s `NodeState` handling][36993]
9493* [Speed up `plug_leaks`][36917]
9494
9495Libraries
9496---------
9497
9498* [`println!()`, with no arguments, prints newline][36825].
9499 Previously, an empty string was required to achieve the same.
9500* [`Wrapping` impls standard binary and unary operators, as well as
9501 the `Sum` and `Product` iterators][37356]
9502* [Implement `From<Cow<str>> for String` and `From<Cow<[T]>> for
9503 Vec<T>`][37326]
9504* [Improve `fold` performance for `chain`, `cloned`, `map`, and
9505 `VecDeque` iterators][37315]
9506* [Improve `SipHasher` performance on small values][37312]
9507* [Add Iterator trait TrustedLen to enable better FromIterator /
9508 Extend][37306]
9509* [Expand `.zip()` specialization to `.map()` and `.cloned()`][37230]
9510* [`ReadDir` implements `Debug`][37221]
9511* [Implement `RefUnwindSafe` for atomic types][37178]
9512* [Specialize `Vec::extend` to `Vec::extend_from_slice`][37094]
9513* [Avoid allocations in `Decoder::read_str`][37064]
9514* [`io::Error` implements `From<io::ErrorKind>`][37037]
9515* [Impl `Debug` for raw pointers to unsized data][36880]
9516* [Don't reuse `HashMap` random seeds][37470]
9517* [The internal memory layout of `HashMap` is more cache-friendly, for
9518 significant improvements in some operations][36692]
9519* [`HashMap` uses less memory on 32-bit architectures][36595]
9520* [Impl `Add<{str, Cow<str>}>` for `Cow<str>`][36430]
9521
9522Cargo
9523-----
9524
9525* [Expose rustc cfg values to build scripts][cargo/3243]
9526* [Allow cargo to work with read-only `CARGO_HOME`][cargo/3259]
9527* [Fix passing --features when testing multiple packages][cargo/3280]
9528* [Use a single profile set per workspace][cargo/3249]
9529* [Load `replace` sections from lock files][cargo/3220]
9530* [Ignore `panic` configuration for test/bench profiles][cargo/3175]
9531
9532Tooling
9533-------
9534
9535* [rustup is the recommended Rust installation method][1.14rustup]
9536* This release includes host (rustc) builds for Linux on MIPS, PowerPC, and
9537 S390x. These are [tier 2] platforms and may have major defects. Follow the
9538 instructions on the website to install, or add the targets to an existing
9539 installation with `rustup target add`. The new target triples are:
9540 - `mips-unknown-linux-gnu`
9541 - `mipsel-unknown-linux-gnu`
9542 - `mips64-unknown-linux-gnuabi64`
9543 - `mips64el-unknown-linux-gnuabi64 `
9544 - `powerpc-unknown-linux-gnu`
9545 - `powerpc64-unknown-linux-gnu`
9546 - `powerpc64le-unknown-linux-gnu`
9547 - `s390x-unknown-linux-gnu `
9548* This release includes target (std) builds for ARM Linux running MUSL
9549 libc. These are [tier 2] platforms and may have major defects. Add the
9550 following triples to an existing rustup installation with `rustup target add`:
9551 - `arm-unknown-linux-musleabi`
9552 - `arm-unknown-linux-musleabihf`
9553 - `armv7-unknown-linux-musleabihf`
9554* This release includes [experimental support for WebAssembly][1.14wasm], via
9555 the `wasm32-unknown-emscripten` target. This target is known to have major
9556 defects. Please test, report, and fix.
9557* rustup no longer installs documentation by default. Run `rustup
9558 component add rust-docs` to install.
9559* [Fix line stepping in debugger][37310]
9560* [Enable line number debuginfo in releases][37280]
9561
9562Misc
9563----
9564
9565* [Disable jemalloc on aarch64/powerpc/mips][37392]
9566* [Add support for Fuchsia OS][37313]
9567* [Detect local-rebuild by only MAJOR.MINOR version][37273]
9568
9569Compatibility Notes
9570-------------------
9571
9572* [A number of forward-compatibility lints used by the compiler
9573 to gradually introduce language changes have been converted
9574 to deny by default][36894]:
9575 - ["use of inaccessible extern crate erroneously allowed"][36886]
9576 - ["type parameter default erroneously allowed in invalid location"][36887]
9577 - ["detects super or self keywords at the beginning of global path"][36888]
9578 - ["two overlapping inherent impls define an item with the same name
9579 were erroneously allowed"][36889]
9580 - ["floating-point constants cannot be used in patterns"][36890]
9581 - ["constants of struct or enum type can only be used in a pattern if
9582 the struct or enum has `#[derive(PartialEq, Eq)]`"][36891]
9583 - ["lifetimes or labels named `'_` were erroneously allowed"][36892]
9584* [Prohibit patterns in trait methods without bodies][37378]
9585* [The atomic `Ordering` enum may not be matched exhaustively][37351]
9586* [Future-proofing `#[no_link]` breaks some obscure cases][37247]
9587* [The `$crate` macro variable is accepted in fewer locations][37213]
9588* [Impls specifying extra region requirements beyond the trait
9589 they implement are rejected][37167]
9590* [Enums may not be unsized][37111]. Unsized enums are intended to
9591 work but never have. For now they are forbidden.
9592* [Enforce the shadowing restrictions from RFC 1560 for today's macros][36767]
9593
9594[tier 2]: https://forge.rust-lang.org/platform-support.html
9595[1.14rustup]: https://internals.rust-lang.org/t/beta-testing-rustup-rs/3316/204
9596[1.14wasm]: https://users.rust-lang.org/t/compiling-to-the-web-with-rust-and-emscripten/7627
9597[36430]: https://github.com/rust-lang/rust/pull/36430
9598[36595]: https://github.com/rust-lang/rust/pull/36595
9599[36692]: https://github.com/rust-lang/rust/pull/36692
9600[36767]: https://github.com/rust-lang/rust/pull/36767
9601[36794]: https://github.com/rust-lang/rust/pull/36794
9602[36798]: https://github.com/rust-lang/rust/pull/36798
9603[36819]: https://github.com/rust-lang/rust/pull/36819
9604[36822]: https://github.com/rust-lang/rust/pull/36822
9605[36825]: https://github.com/rust-lang/rust/pull/36825
9606[36843]: https://github.com/rust-lang/rust/pull/36843
9607[36880]: https://github.com/rust-lang/rust/pull/36880
9608[36886]: https://github.com/rust-lang/rust/issues/36886
9609[36887]: https://github.com/rust-lang/rust/issues/36887
9610[36888]: https://github.com/rust-lang/rust/issues/36888
9611[36889]: https://github.com/rust-lang/rust/issues/36889
9612[36890]: https://github.com/rust-lang/rust/issues/36890
9613[36891]: https://github.com/rust-lang/rust/issues/36891
9614[36892]: https://github.com/rust-lang/rust/issues/36892
9615[36894]: https://github.com/rust-lang/rust/pull/36894
9616[36917]: https://github.com/rust-lang/rust/pull/36917
9617[36993]: https://github.com/rust-lang/rust/pull/36993
9618[37037]: https://github.com/rust-lang/rust/pull/37037
9619[37064]: https://github.com/rust-lang/rust/pull/37064
9620[37094]: https://github.com/rust-lang/rust/pull/37094
9621[37108]: https://github.com/rust-lang/rust/pull/37108
9622[37111]: https://github.com/rust-lang/rust/pull/37111
9623[37161]: https://github.com/rust-lang/rust/pull/37161
9624[37162]: https://github.com/rust-lang/rust/pull/37162
9625[37167]: https://github.com/rust-lang/rust/pull/37167
9626[37178]: https://github.com/rust-lang/rust/pull/37178
9627[37200]: https://github.com/rust-lang/rust/pull/37200
9628[37213]: https://github.com/rust-lang/rust/pull/37213
9629[37221]: https://github.com/rust-lang/rust/pull/37221
9630[37224]: https://github.com/rust-lang/rust/pull/37224
9631[37230]: https://github.com/rust-lang/rust/pull/37230
9632[37231]: https://github.com/rust-lang/rust/pull/37231
9633[37247]: https://github.com/rust-lang/rust/pull/37247
9634[37267]: https://github.com/rust-lang/rust/pull/37267
9635[37270]: https://github.com/rust-lang/rust/pull/37270
9636[37273]: https://github.com/rust-lang/rust/pull/37273
9637[37280]: https://github.com/rust-lang/rust/pull/37280
9638[37298]: https://github.com/rust-lang/rust/pull/37298
9639[37306]: https://github.com/rust-lang/rust/pull/37306
9640[37310]: https://github.com/rust-lang/rust/pull/37310
9641[37312]: https://github.com/rust-lang/rust/pull/37312
9642[37313]: https://github.com/rust-lang/rust/pull/37313
9643[37315]: https://github.com/rust-lang/rust/pull/37315
9644[37318]: https://github.com/rust-lang/rust/pull/37318
9645[37322]: https://github.com/rust-lang/rust/pull/37322
9646[37326]: https://github.com/rust-lang/rust/pull/37326
9647[37351]: https://github.com/rust-lang/rust/pull/37351
9648[37356]: https://github.com/rust-lang/rust/pull/37356
9649[37367]: https://github.com/rust-lang/rust/pull/37367
9650[37373]: https://github.com/rust-lang/rust/pull/37373
9651[37378]: https://github.com/rust-lang/rust/pull/37378
9652[37389]: https://github.com/rust-lang/rust/pull/37389
9653[37392]: https://github.com/rust-lang/rust/pull/37392
9654[37427]: https://github.com/rust-lang/rust/pull/37427
9655[37439]: https://github.com/rust-lang/rust/pull/37439
9656[37445]: https://github.com/rust-lang/rust/pull/37445
9657[37470]: https://github.com/rust-lang/rust/pull/37470
9658[37569]: https://github.com/rust-lang/rust/pull/37569
9659[RFC 1492]: https://github.com/rust-lang/rfcs/blob/master/text/1492-dotdot-in-patterns.md
9660[cargo/3175]: https://github.com/rust-lang/cargo/pull/3175
9661[cargo/3220]: https://github.com/rust-lang/cargo/pull/3220
9662[cargo/3243]: https://github.com/rust-lang/cargo/pull/3243
9663[cargo/3249]: https://github.com/rust-lang/cargo/pull/3249
9664[cargo/3259]: https://github.com/rust-lang/cargo/pull/3259
9665[cargo/3280]: https://github.com/rust-lang/cargo/pull/3280
9666
9667
9668Version 1.13.0 (2016-11-10)
9669===========================
9670
9671Language
9672--------
9673
9674* [Stabilize the `?` operator][36995]. `?` is a simple way to propagate
9675 errors, like the `try!` macro, described in [RFC 0243].
9676* [Stabilize macros in type position][36014]. Described in [RFC 873].
9677* [Stabilize attributes on statements][36995]. Described in [RFC 0016].
9678* [Fix `#[derive]` for empty tuple structs/variants][35728]
9679* [Fix lifetime rules for 'if' conditions][36029]
9680* [Avoid loading and parsing unconfigured non-inline modules][36482]
9681
9682Compiler
9683--------
9684
9685* [Add the `-C link-arg` argument][36574]
9686* [Remove the old AST-based backend from rustc_trans][35764]
9687* [Don't enable NEON by default on armv7 Linux][35814]
9688* [Fix debug line number info for macro expansions][35238]
9689* [Do not emit "class method" debuginfo for types that are not
9690 DICompositeType][36008]
9691* [Warn about multiple conflicting #[repr] hints][34623]
9692* [When sizing DST, don't double-count nested struct prefixes][36351]
9693* [Default RUST_MIN_STACK to 16MiB for now][36505]
9694* [Improve rlib metadata format][36551]. Reduces rlib size significantly.
9695* [Reject macros with empty repetitions to avoid infinite loop][36721]
9696* [Expand macros without recursing to avoid stack overflows][36214]
9697
9698Diagnostics
9699-----------
9700
9701* [Replace macro backtraces with labeled local uses][35702]
9702* [Improve error message for misplaced doc comments][33922]
9703* [Buffer unix and lock windows to prevent message interleaving][35975]
9704* [Update lifetime errors to specifically note temporaries][36171]
9705* [Special case a few colors for Windows][36178]
9706* [Suggest `use self` when such an import resolves][36289]
9707* [Be more specific when type parameter shadows primitive type][36338]
9708* Many minor improvements
9709
9710Compile-time Optimizations
9711--------------------------
9712
9713* [Compute and cache HIR hashes at beginning][35854]
9714* [Don't hash types in loan paths][36004]
9715* [Cache projections in trans][35761]
9716* [Optimize the parser's last token handling][36527]
9717* [Only instantiate #[inline] functions in codegen units referencing
9718 them][36524]. This leads to big improvements in cases where crates export
9719 define many inline functions without using them directly.
9720* [Lazily allocate TypedArena's first chunk][36592]
9721* [Don't allocate during default HashSet creation][36734]
9722
9723Stabilized APIs
9724---------------
9725
9726* [`checked_abs`]
9727* [`wrapping_abs`]
9728* [`overflowing_abs`]
9729* [`RefCell::try_borrow`]
9730* [`RefCell::try_borrow_mut`]
9731
9732Libraries
9733---------
9734
9735* [Add `assert_ne!` and `debug_assert_ne!`][35074]
9736* [Make `vec_deque::Drain`, `hash_map::Drain`, and `hash_set::Drain`
9737 covariant][35354]
9738* [Implement `AsRef<[T]>` for `std::slice::Iter`][35559]
9739* [Implement `Debug` for `std::vec::IntoIter`][35707]
9740* [`CString`: avoid excessive growth just to 0-terminate][35871]
9741* [Implement `CoerceUnsized` for `{Cell, RefCell, UnsafeCell}`][35627]
9742* [Use arc4rand on FreeBSD][35884]
9743* [memrchr: Correct aligned offset computation][35969]
9744* [Improve Demangling of Rust Symbols][36059]
9745* [Use monotonic time in condition variables][35048]
9746* [Implement `Debug` for `std::path::{Components,Iter}`][36101]
9747* [Implement conversion traits for `char`][35755]
9748* [Fix illegal instruction caused by overflow in channel cloning][36104]
9749* [Zero first byte of CString on drop][36264]
9750* [Inherit overflow checks for sum and product][36372]
9751* [Add missing Eq implementations][36423]
9752* [Implement `Debug` for `DirEntry`][36631]
9753* [When `getaddrinfo` returns `EAI_SYSTEM` retrieve actual error from
9754 `errno`][36754]
9755* [`SipHasher`] is deprecated. Use [`DefaultHasher`].
9756* [Implement more traits for `std::io::ErrorKind`][35911]
9757* [Optimize BinaryHeap bounds checking][36072]
9758* [Work around pointer aliasing issue in `Vec::extend_from_slice`,
9759 `extend_with_element`][36355]
9760* [Fix overflow checking in unsigned pow()][34942]
9761
9762Cargo
9763-----
9764
9765* This release includes security fixes to both curl and OpenSSL.
9766* [Fix transitive doctests when panic=abort][cargo/3021]
9767* [Add --all-features flag to cargo][cargo/3038]
9768* [Reject path-based dependencies in `cargo package`][cargo/3060]
9769* [Don't parse the home directory more than once][cargo/3078]
9770* [Don't try to generate Cargo.lock on empty workspaces][cargo/3092]
9771* [Update OpenSSL to 1.0.2j][cargo/3121]
9772* [Add license and license_file to cargo metadata output][cargo/3110]
9773* [Make crates-io registry URL optional in config; ignore all changes to
9774 source.crates-io][cargo/3089]
9775* [Don't download dependencies from other platforms][cargo/3123]
9776* [Build transitive dev-dependencies when needed][cargo/3125]
9777* [Add support for per-target rustflags in .cargo/config][cargo/3157]
9778* [Avoid updating registry when adding existing deps][cargo/3144]
9779* [Warn about path overrides that won't work][cargo/3136]
9780* [Use workspaces during `cargo install`][cargo/3146]
9781* [Leak mspdbsrv.exe processes on Windows][cargo/3162]
9782* [Add --message-format flag][cargo/3000]
9783* [Pass target environment for rustdoc][cargo/3205]
9784* [Use `CommandExt::exec` for `cargo run` on Unix][cargo/2818]
9785* [Update curl and curl-sys][cargo/3241]
9786* [Call rustdoc test with the correct cfg flags of a package][cargo/3242]
9787
9788Tooling
9789-------
9790
9791* [rustdoc: Add the `--sysroot` argument][36586]
9792* [rustdoc: Fix a couple of issues with the search results][35655]
9793* [rustdoc: remove the `!` from macro URLs and titles][35234]
9794* [gdb: Fix pretty-printing special-cased Rust types][35585]
9795* [rustdoc: Filter more incorrect methods inherited through Deref][36266]
9796
9797Misc
9798----
9799
9800* [Remove unmaintained style guide][35124]
9801* [Add s390x support][36369]
9802* [Initial work at Haiku OS support][36727]
9803* [Add mips-uclibc targets][35734]
9804* [Crate-ify compiler-rt into compiler-builtins][35021]
9805* [Add rustc version info (git hash + date) to dist tarball][36213]
9806* Many documentation improvements
9807
9808Compatibility Notes
9809-------------------
9810
9811* [`SipHasher`] is deprecated. Use [`DefaultHasher`].
9812* [Deny (by default) transmuting from fn item types to pointer-sized
9813 types][34923]. Continuing the long transition to zero-sized fn items,
9814 per [RFC 401].
9815* [Fix `#[derive]` for empty tuple structs/variants][35728].
9816 Part of [RFC 1506].
9817* [Issue deprecation warnings for safe accesses to extern statics][36173]
9818* [Fix lifetime rules for 'if' conditions][36029].
9819* [Inherit overflow checks for sum and product][36372].
9820* [Forbid user-defined macros named "macro_rules"][36730].
9821
9822[33922]: https://github.com/rust-lang/rust/pull/33922
9823[34623]: https://github.com/rust-lang/rust/pull/34623
9824[34923]: https://github.com/rust-lang/rust/pull/34923
9825[34942]: https://github.com/rust-lang/rust/pull/34942
9826[35021]: https://github.com/rust-lang/rust/pull/35021
9827[35048]: https://github.com/rust-lang/rust/pull/35048
9828[35074]: https://github.com/rust-lang/rust/pull/35074
9829[35124]: https://github.com/rust-lang/rust/pull/35124
9830[35234]: https://github.com/rust-lang/rust/pull/35234
9831[35238]: https://github.com/rust-lang/rust/pull/35238
9832[35354]: https://github.com/rust-lang/rust/pull/35354
9833[35559]: https://github.com/rust-lang/rust/pull/35559
9834[35585]: https://github.com/rust-lang/rust/pull/35585
9835[35627]: https://github.com/rust-lang/rust/pull/35627
9836[35655]: https://github.com/rust-lang/rust/pull/35655
9837[35702]: https://github.com/rust-lang/rust/pull/35702
9838[35707]: https://github.com/rust-lang/rust/pull/35707
9839[35728]: https://github.com/rust-lang/rust/pull/35728
9840[35734]: https://github.com/rust-lang/rust/pull/35734
9841[35755]: https://github.com/rust-lang/rust/pull/35755
9842[35761]: https://github.com/rust-lang/rust/pull/35761
9843[35764]: https://github.com/rust-lang/rust/pull/35764
9844[35814]: https://github.com/rust-lang/rust/pull/35814
9845[35854]: https://github.com/rust-lang/rust/pull/35854
9846[35871]: https://github.com/rust-lang/rust/pull/35871
9847[35884]: https://github.com/rust-lang/rust/pull/35884
9848[35911]: https://github.com/rust-lang/rust/pull/35911
9849[35969]: https://github.com/rust-lang/rust/pull/35969
9850[35975]: https://github.com/rust-lang/rust/pull/35975
9851[36004]: https://github.com/rust-lang/rust/pull/36004
9852[36008]: https://github.com/rust-lang/rust/pull/36008
9853[36014]: https://github.com/rust-lang/rust/pull/36014
9854[36029]: https://github.com/rust-lang/rust/pull/36029
9855[36059]: https://github.com/rust-lang/rust/pull/36059
9856[36072]: https://github.com/rust-lang/rust/pull/36072
9857[36101]: https://github.com/rust-lang/rust/pull/36101
9858[36104]: https://github.com/rust-lang/rust/pull/36104
9859[36171]: https://github.com/rust-lang/rust/pull/36171
9860[36173]: https://github.com/rust-lang/rust/pull/36173
9861[36178]: https://github.com/rust-lang/rust/pull/36178
9862[36213]: https://github.com/rust-lang/rust/pull/36213
9863[36214]: https://github.com/rust-lang/rust/pull/36214
9864[36264]: https://github.com/rust-lang/rust/pull/36264
9865[36266]: https://github.com/rust-lang/rust/pull/36266
9866[36289]: https://github.com/rust-lang/rust/pull/36289
9867[36338]: https://github.com/rust-lang/rust/pull/36338
9868[36351]: https://github.com/rust-lang/rust/pull/36351
9869[36355]: https://github.com/rust-lang/rust/pull/36355
9870[36369]: https://github.com/rust-lang/rust/pull/36369
9871[36372]: https://github.com/rust-lang/rust/pull/36372
9872[36423]: https://github.com/rust-lang/rust/pull/36423
9873[36482]: https://github.com/rust-lang/rust/pull/36482
9874[36505]: https://github.com/rust-lang/rust/pull/36505
9875[36524]: https://github.com/rust-lang/rust/pull/36524
9876[36527]: https://github.com/rust-lang/rust/pull/36527
9877[36551]: https://github.com/rust-lang/rust/pull/36551
9878[36574]: https://github.com/rust-lang/rust/pull/36574
9879[36586]: https://github.com/rust-lang/rust/pull/36586
9880[36592]: https://github.com/rust-lang/rust/pull/36592
9881[36631]: https://github.com/rust-lang/rust/pull/36631
9882[36721]: https://github.com/rust-lang/rust/pull/36721
9883[36727]: https://github.com/rust-lang/rust/pull/36727
9884[36730]: https://github.com/rust-lang/rust/pull/36730
9885[36734]: https://github.com/rust-lang/rust/pull/36734
9886[36754]: https://github.com/rust-lang/rust/pull/36754
9887[36995]: https://github.com/rust-lang/rust/pull/36995
9888[RFC 0016]: https://github.com/rust-lang/rfcs/blob/master/text/0016-more-attributes.md
9889[RFC 0243]: https://github.com/rust-lang/rfcs/blob/master/text/0243-trait-based-exception-handling.md
9890[RFC 1506]: https://github.com/rust-lang/rfcs/blob/master/text/1506-adt-kinds.md
9891[RFC 401]: https://github.com/rust-lang/rfcs/blob/master/text/0401-coercions.md
9892[RFC 873]: https://github.com/rust-lang/rfcs/blob/master/text/0873-type-macros.md
9893[cargo/2818]: https://github.com/rust-lang/cargo/pull/2818
9894[cargo/3000]: https://github.com/rust-lang/cargo/pull/3000
9895[cargo/3021]: https://github.com/rust-lang/cargo/pull/3021
9896[cargo/3038]: https://github.com/rust-lang/cargo/pull/3038
9897[cargo/3060]: https://github.com/rust-lang/cargo/pull/3060
9898[cargo/3078]: https://github.com/rust-lang/cargo/pull/3078
9899[cargo/3089]: https://github.com/rust-lang/cargo/pull/3089
9900[cargo/3092]: https://github.com/rust-lang/cargo/pull/3092
9901[cargo/3110]: https://github.com/rust-lang/cargo/pull/3110
9902[cargo/3121]: https://github.com/rust-lang/cargo/pull/3121
9903[cargo/3123]: https://github.com/rust-lang/cargo/pull/3123
9904[cargo/3125]: https://github.com/rust-lang/cargo/pull/3125
9905[cargo/3136]: https://github.com/rust-lang/cargo/pull/3136
9906[cargo/3144]: https://github.com/rust-lang/cargo/pull/3144
9907[cargo/3146]: https://github.com/rust-lang/cargo/pull/3146
9908[cargo/3157]: https://github.com/rust-lang/cargo/pull/3157
9909[cargo/3162]: https://github.com/rust-lang/cargo/pull/3162
9910[cargo/3205]: https://github.com/rust-lang/cargo/pull/3205
9911[cargo/3241]: https://github.com/rust-lang/cargo/pull/3241
9912[cargo/3242]: https://github.com/rust-lang/cargo/pull/3242
9913[`checked_abs`]: https://doc.rust-lang.org/std/primitive.i32.html#method.checked_abs
9914[`wrapping_abs`]: https://doc.rust-lang.org/std/primitive.i32.html#method.wrapping_abs
9915[`overflowing_abs`]: https://doc.rust-lang.org/std/primitive.i32.html#method.overflowing_abs
9916[`RefCell::try_borrow`]: https://doc.rust-lang.org/std/cell/struct.RefCell.html#method.try_borrow
9917[`RefCell::try_borrow_mut`]: https://doc.rust-lang.org/std/cell/struct.RefCell.html#method.try_borrow_mut
9918[`SipHasher`]: https://doc.rust-lang.org/std/hash/struct.SipHasher.html
9919[`DefaultHasher`]: https://doc.rust-lang.org/std/collections/hash_map/struct.DefaultHasher.html
9920
9921
9922Version 1.12.1 (2016-10-20)
9923===========================
9924
9925Regression Fixes
9926----------------
9927
9928* [ICE: 'rustc' panicked at 'assertion failed: concrete_substs.is_normalized_for_trans()' #36381][36381]
9929* [Confusion with double negation and booleans][36856]
9930* [rustc 1.12.0 fails with SIGSEGV in release mode (syn crate 0.8.0)][36875]
9931* [Rustc 1.12.0 Windows build of `ethcore` crate fails with LLVM error][36924]
9932* [1.12.0: High memory usage when linking in release mode with debug info][36926]
9933* [Corrupted memory after updated to 1.12][36936]
9934* ["Let NullaryConstructor = something;" causes internal compiler error: "tried to overwrite interned AdtDef"][37026]
9935* [Fix ICE: inject bitcast if types mismatch for invokes/calls/stores][37112]
9936* [debuginfo: Handle spread_arg case in MIR-trans in a more stable way.][37153]
9937
9938[36381]: https://github.com/rust-lang/rust/issues/36381
9939[36856]: https://github.com/rust-lang/rust/issues/36856
9940[36875]: https://github.com/rust-lang/rust/issues/36875
9941[36924]: https://github.com/rust-lang/rust/issues/36924
9942[36926]: https://github.com/rust-lang/rust/issues/36926
9943[36936]: https://github.com/rust-lang/rust/issues/36936
9944[37026]: https://github.com/rust-lang/rust/issues/37026
9945[37112]: https://github.com/rust-lang/rust/issues/37112
9946[37153]: https://github.com/rust-lang/rust/issues/37153
9947
9948
9949Version 1.12.0 (2016-09-29)
9950===========================
9951
9952Highlights
9953----------
9954
9955* [`rustc` translates code to LLVM IR via its own "middle" IR (MIR)](https://github.com/rust-lang/rust/pull/34096).
9956 This translation pass is far simpler than the previous AST->LLVM pass, and
9957 creates opportunities to perform new optimizations directly on the MIR. It
9958 was previously described [on the Rust blog](https://blog.rust-lang.org/2016/04/19/MIR.html).
9959* [`rustc` presents a new, more readable error format, along with
9960 machine-readable JSON error output for use by IDEs](https://github.com/rust-lang/rust/pull/35401).
9961 Most common editors supporting Rust have been updated to work with it. It was
9962 previously described [on the Rust blog](https://blog.rust-lang.org/2016/08/10/Shape-of-errors-to-come.html).
9963
9964Compiler
9965--------
9966
9967* [`rustc` translates code to LLVM IR via its own "middle" IR (MIR)](https://github.com/rust-lang/rust/pull/34096).
9968 This translation pass is far simpler than the previous AST->LLVM pass, and
9969 creates opportunities to perform new optimizations directly on the MIR. It
9970 was previously described [on the Rust blog](https://blog.rust-lang.org/2016/04/19/MIR.html).
9971* [Print the Rust target name, not the LLVM target name, with
9972 `--print target-list`](https://github.com/rust-lang/rust/pull/35489)
9973* [The computation of `TypeId` is correct in some cases where it was previously
9974 producing inconsistent results](https://github.com/rust-lang/rust/pull/35267)
9975* [The `mips-unknown-linux-gnu` target uses hardware floating point by default](https://github.com/rust-lang/rust/pull/34910)
9976* [The `rustc` arguments, `--print target-cpus`, `--print target-features`,
9977 `--print relocation-models`, and `--print code-models` print the available
9978 options to the `-C target-cpu`, `-C target-feature`, `-C relocation-model` and
9979 `-C code-model` code generation arguments](https://github.com/rust-lang/rust/pull/34845)
9980* [`rustc` supports three new MUSL targets on ARM: `arm-unknown-linux-musleabi`,
9981 `arm-unknown-linux-musleabihf`, and `armv7-unknown-linux-musleabihf`](https://github.com/rust-lang/rust/pull/35060).
9982 These targets produce statically-linked binaries. There are no binary release
9983 builds yet though.
9984
9985Diagnostics
9986-----------
9987
9988* [`rustc` presents a new, more readable error format, along with
9989 machine-readable JSON error output for use by IDEs](https://github.com/rust-lang/rust/pull/35401).
9990 Most common editors supporting Rust have been updated to work with it. It was
9991 previously described [on the Rust blog](https://blog.rust-lang.org/2016/08/10/Shape-of-errors-to-come.html).
9992* [In error descriptions, references are now described in plain English,
9993 instead of as "&-ptr"](https://github.com/rust-lang/rust/pull/35611)
9994* [In error type descriptions, unknown numeric types are named `{integer}` or
9995 `{float}` instead of `_`](https://github.com/rust-lang/rust/pull/35080)
9996* [`rustc` emits a clearer error when inner attributes follow a doc comment](https://github.com/rust-lang/rust/pull/34676)
9997
9998Language
9999--------
10000
10001* [`macro_rules!` invocations can be made within `macro_rules!` invocations](https://github.com/rust-lang/rust/pull/34925)
10002* [`macro_rules!` meta-variables are hygienic](https://github.com/rust-lang/rust/pull/35453)
10003* [`macro_rules!` `tt` matchers can be reparsed correctly, making them much more
10004 useful](https://github.com/rust-lang/rust/pull/34908)
10005* [`macro_rules!` `stmt` matchers correctly consume the entire contents when
10006 inside non-braces invocations](https://github.com/rust-lang/rust/pull/34886)
10007* [Semicolons are properly required as statement delimiters inside
10008 `macro_rules!` invocations](https://github.com/rust-lang/rust/pull/34660)
10009* [`cfg_attr` works on `path` attributes](https://github.com/rust-lang/rust/pull/34546)
10010
10011Stabilized APIs
10012---------------
10013
10014* [`Cell::as_ptr`](https://doc.rust-lang.org/std/cell/struct.Cell.html#method.as_ptr)
10015* [`RefCell::as_ptr`](https://doc.rust-lang.org/std/cell/struct.RefCell.html#method.as_ptr)
10016* [`IpAddr::is_unspecified`](https://doc.rust-lang.org/std/net/enum.IpAddr.html#method.is_unspecified)
10017* [`IpAddr::is_loopback`](https://doc.rust-lang.org/std/net/enum.IpAddr.html#method.is_loopback)
10018* [`IpAddr::is_multicast`](https://doc.rust-lang.org/std/net/enum.IpAddr.html#method.is_multicast)
10019* [`Ipv4Addr::is_unspecified`](https://doc.rust-lang.org/std/net/struct.Ipv4Addr.html#method.is_unspecified)
10020* [`Ipv6Addr::octets`](https://doc.rust-lang.org/std/net/struct.Ipv6Addr.html#method.octets)
10021* [`LinkedList::contains`](https://doc.rust-lang.org/std/collections/linked_list/struct.LinkedList.html#method.contains)
10022* [`VecDeque::contains`](https://doc.rust-lang.org/std/collections/vec_deque/struct.VecDeque.html#method.contains)
10023* [`ExitStatusExt::from_raw`](https://doc.rust-lang.org/std/os/unix/process/trait.ExitStatusExt.html#tymethod.from_raw).
10024 Both on Unix and Windows.
10025* [`Receiver::recv_timeout`](https://doc.rust-lang.org/std/sync/mpsc/struct.Receiver.html#method.recv_timeout)
10026* [`RecvTimeoutError`](https://doc.rust-lang.org/std/sync/mpsc/enum.RecvTimeoutError.html)
10027* [`BinaryHeap::peek_mut`](https://doc.rust-lang.org/std/collections/binary_heap/struct.BinaryHeap.html#method.peek_mut)
10028* [`PeekMut`](https://doc.rust-lang.org/std/collections/binary_heap/struct.PeekMut.html)
10029* [`iter::Product`](https://doc.rust-lang.org/std/iter/trait.Product.html)
10030* [`iter::Sum`](https://doc.rust-lang.org/std/iter/trait.Sum.html)
10031* [`OccupiedEntry::remove_entry`](https://doc.rust-lang.org/std/collections/btree_map/struct.OccupiedEntry.html#method.remove_entry)
10032* [`VacantEntry::into_key`](https://doc.rust-lang.org/std/collections/btree_map/struct.VacantEntry.html#method.into_key)
10033
10034Libraries
10035---------
10036
10037* [The `format!` macro and friends now allow a single argument to be formatted
10038 in multiple styles](https://github.com/rust-lang/rust/pull/33642)
10039* [The lifetime bounds on `[T]::binary_search_by` and
10040 `[T]::binary_search_by_key` have been adjusted to be more flexible](https://github.com/rust-lang/rust/pull/34762)
10041* [`Option` implements `From` for its contained type](https://github.com/rust-lang/rust/pull/34828)
10042* [`Cell`, `RefCell` and `UnsafeCell` implement `From` for their contained type](https://github.com/rust-lang/rust/pull/35392)
10043* [`RwLock` panics if the reader count overflows](https://github.com/rust-lang/rust/pull/35378)
10044* [`vec_deque::Drain`, `hash_map::Drain` and `hash_set::Drain` are covariant](https://github.com/rust-lang/rust/pull/35354)
10045* [`vec::Drain` and `binary_heap::Drain` are covariant](https://github.com/rust-lang/rust/pull/34951)
10046* [`Cow<str>` implements `FromIterator` for `char`, `&str` and `String`](https://github.com/rust-lang/rust/pull/35064)
10047* [Sockets on Linux are correctly closed in subprocesses via `SOCK_CLOEXEC`](https://github.com/rust-lang/rust/pull/34946)
10048* [`hash_map::Entry`, `hash_map::VacantEntry` and `hash_map::OccupiedEntry`
10049 implement `Debug`](https://github.com/rust-lang/rust/pull/34937)
10050* [`btree_map::Entry`, `btree_map::VacantEntry` and `btree_map::OccupiedEntry`
10051 implement `Debug`](https://github.com/rust-lang/rust/pull/34885)
10052* [`String` implements `AddAssign`](https://github.com/rust-lang/rust/pull/34890)
10053* [Variadic `extern fn` pointers implement the `Clone`, `PartialEq`, `Eq`,
10054 `PartialOrd`, `Ord`, `Hash`, `fmt::Pointer`, and `fmt::Debug` traits](https://github.com/rust-lang/rust/pull/34879)
10055* [`FileType` implements `Debug`](https://github.com/rust-lang/rust/pull/34757)
10056* [References to `Mutex` and `RwLock` are unwind-safe](https://github.com/rust-lang/rust/pull/34756)
10057* [`mpsc::sync_channel` `Receiver`s return any available message before
10058 reporting a disconnect](https://github.com/rust-lang/rust/pull/34731)
10059* [Unicode definitions have been updated to 9.0](https://github.com/rust-lang/rust/pull/34599)
10060* [`env` iterators implement `DoubleEndedIterator`](https://github.com/rust-lang/rust/pull/33312)
10061
10062Cargo
10063-----
10064
10065* [Support local mirrors of registries](https://github.com/rust-lang/cargo/pull/2857)
10066* [Add support for command aliases](https://github.com/rust-lang/cargo/pull/2679)
10067* [Allow `opt-level="s"` / `opt-level="z"` in profile overrides](https://github.com/rust-lang/cargo/pull/3007)
10068* [Make `cargo doc --open --target` work as expected](https://github.com/rust-lang/cargo/pull/2988)
10069* [Speed up noop registry updates](https://github.com/rust-lang/cargo/pull/2974)
10070* [Update OpenSSL](https://github.com/rust-lang/cargo/pull/2971)
10071* [Fix `--panic=abort` with plugins](https://github.com/rust-lang/cargo/pull/2954)
10072* [Always pass `-C metadata` to the compiler](https://github.com/rust-lang/cargo/pull/2946)
10073* [Fix depending on git repos with workspaces](https://github.com/rust-lang/cargo/pull/2938)
10074* [Add a `--lib` flag to `cargo new`](https://github.com/rust-lang/cargo/pull/2921)
10075* [Add `http.cainfo` for custom certs](https://github.com/rust-lang/cargo/pull/2917)
10076* [Indicate the compilation profile after compiling](https://github.com/rust-lang/cargo/pull/2909)
10077* [Allow enabling features for dependencies with `--features`](https://github.com/rust-lang/cargo/pull/2876)
10078* [Add `--jobs` flag to `cargo package`](https://github.com/rust-lang/cargo/pull/2867)
10079* [Add `--dry-run` to `cargo publish`](https://github.com/rust-lang/cargo/pull/2849)
10080* [Add support for `RUSTDOCFLAGS`](https://github.com/rust-lang/cargo/pull/2794)
10081
10082Performance
10083-----------
10084
10085* [`panic::catch_unwind` is more optimized](https://github.com/rust-lang/rust/pull/35444)
10086* [`panic::catch_unwind` no longer accesses thread-local storage on entry](https://github.com/rust-lang/rust/pull/34866)
10087
10088Tooling
10089-------
10090
10091* [Test binaries now support a `--test-threads` argument to specify the number
10092 of threads used to run tests, and which acts the same as the
10093 `RUST_TEST_THREADS` environment variable](https://github.com/rust-lang/rust/pull/35414)
10094* [The test runner now emits a warning when tests run over 60 seconds](https://github.com/rust-lang/rust/pull/35405)
10095* [rustdoc: Fix methods in search results](https://github.com/rust-lang/rust/pull/34752)
10096* [`rust-lldb` warns about unsupported versions of LLDB](https://github.com/rust-lang/rust/pull/34646)
10097* [Rust releases now come with source packages that can be installed by rustup
10098 via `rustup component add rust-src`](https://github.com/rust-lang/rust/pull/34366).
10099 The resulting source code can be used by tools and IDES, located in the
10100 sysroot under `lib/rustlib/src`.
10101
10102Misc
10103----
10104
10105* [The compiler can now be built against LLVM 3.9](https://github.com/rust-lang/rust/pull/35594)
10106* Many minor improvements to the documentation.
10107* [The Rust exception handling "personality" routine is now written in Rust](https://github.com/rust-lang/rust/pull/34832)
10108
10109Compatibility Notes
10110-------------------
10111
10112* [When printing Windows `OsStr`s, unpaired surrogate codepoints are escaped
10113 with the lowercase format instead of the uppercase](https://github.com/rust-lang/rust/pull/35084)
10114* [When formatting strings, if "precision" is specified, the "fill",
10115 "align" and "width" specifiers are no longer ignored](https://github.com/rust-lang/rust/pull/34544)
10116* [The `Debug` impl for strings no longer escapes all non-ASCII characters](https://github.com/rust-lang/rust/pull/34485)
10117
10118
10119Version 1.11.0 (2016-08-18)
10120===========================
10121
10122Language
10123--------
10124
10125* [Support nested `cfg_attr` attributes](https://github.com/rust-lang/rust/pull/34216)
10126* [Allow statement-generating braced macro invocations at the end of blocks](https://github.com/rust-lang/rust/pull/34436)
10127* [Macros can be expanded inside of trait definitions](https://github.com/rust-lang/rust/pull/34213)
10128* [`#[macro_use]` works properly when it is itself expanded from a macro](https://github.com/rust-lang/rust/pull/34032)
10129
10130Stabilized APIs
10131---------------
10132
10133* [`BinaryHeap::append`](https://doc.rust-lang.org/std/collections/binary_heap/struct.BinaryHeap.html#method.append)
10134* [`BTreeMap::append`](https://doc.rust-lang.org/std/collections/btree_map/struct.BTreeMap.html#method.append)
10135* [`BTreeMap::split_off`](https://doc.rust-lang.org/std/collections/btree_map/struct.BTreeMap.html#method.split_off)
10136* [`BTreeSet::append`](https://doc.rust-lang.org/std/collections/btree_set/struct.BTreeSet.html#method.append)
10137* [`BTreeSet::split_off`](https://doc.rust-lang.org/std/collections/btree_set/struct.BTreeSet.html#method.split_off)
10138* [`f32::to_degrees`](https://doc.rust-lang.org/std/primitive.f32.html#method.to_degrees)
10139 (in libcore - previously stabilized in libstd)
10140* [`f32::to_radians`](https://doc.rust-lang.org/std/primitive.f32.html#method.to_radians)
10141 (in libcore - previously stabilized in libstd)
10142* [`f64::to_degrees`](https://doc.rust-lang.org/std/primitive.f64.html#method.to_degrees)
10143 (in libcore - previously stabilized in libstd)
10144* [`f64::to_radians`](https://doc.rust-lang.org/std/primitive.f64.html#method.to_radians)
10145 (in libcore - previously stabilized in libstd)
10146* [`Iterator::sum`](https://doc.rust-lang.org/std/iter/trait.Iterator.html#method.sum)
10147* [`Iterator::product`](https://doc.rust-lang.org/std/iter/trait.Iterator.html#method.product)
10148* [`Cell::get_mut`](https://doc.rust-lang.org/std/cell/struct.Cell.html#method.get_mut)
10149* [`RefCell::get_mut`](https://doc.rust-lang.org/std/cell/struct.RefCell.html#method.get_mut)
10150
10151Libraries
10152---------
10153
10154* [The `thread_local!` macro supports multiple definitions in a single
10155 invocation, and can apply attributes](https://github.com/rust-lang/rust/pull/34077)
10156* [`Cow` implements `Default`](https://github.com/rust-lang/rust/pull/34305)
10157* [`Wrapping` implements binary, octal, lower-hex and upper-hex
10158 `Display` formatting](https://github.com/rust-lang/rust/pull/34190)
10159* [The range types implement `Hash`](https://github.com/rust-lang/rust/pull/34180)
10160* [`lookup_host` ignores unknown address types](https://github.com/rust-lang/rust/pull/34067)
10161* [`assert_eq!` accepts a custom error message, like `assert!` does](https://github.com/rust-lang/rust/pull/33976)
10162* [The main thread is now called "main" instead of "&lt;main&gt;"](https://github.com/rust-lang/rust/pull/33803)
10163
10164Cargo
10165-----
10166
10167* [Disallow specifying features of transitive deps](https://github.com/rust-lang/cargo/pull/2821)
10168* [Add color support for Windows consoles](https://github.com/rust-lang/cargo/pull/2804)
10169* [Fix `harness = false` on `[lib]` sections](https://github.com/rust-lang/cargo/pull/2795)
10170* [Don't panic when `links` contains a '.'](https://github.com/rust-lang/cargo/pull/2787)
10171* [Build scripts can emit warnings](https://github.com/rust-lang/cargo/pull/2630),
10172 and `-vv` prints warnings for all crates.
10173* [Ignore file locks on OS X NFS mounts](https://github.com/rust-lang/cargo/pull/2720)
10174* [Don't warn about `package.metadata` keys](https://github.com/rust-lang/cargo/pull/2668).
10175 This provides room for expansion by arbitrary tools.
10176* [Add support for cdylib crate types](https://github.com/rust-lang/cargo/pull/2741)
10177* [Prevent publishing crates when files are dirty](https://github.com/rust-lang/cargo/pull/2781)
10178* [Don't fetch all crates on clean](https://github.com/rust-lang/cargo/pull/2704)
10179* [Propagate --color option to rustc](https://github.com/rust-lang/cargo/pull/2779)
10180* [Fix `cargo doc --open` on Windows](https://github.com/rust-lang/cargo/pull/2780)
10181* [Improve autocompletion](https://github.com/rust-lang/cargo/pull/2772)
10182* [Configure colors of stderr as well as stdout](https://github.com/rust-lang/cargo/pull/2739)
10183
10184Performance
10185-----------
10186
10187* [Caching projections speeds up type check dramatically for some
10188 workloads](https://github.com/rust-lang/rust/pull/33816)
10189* [The default `HashMap` hasher is SipHash 1-3 instead of SipHash 2-4](https://github.com/rust-lang/rust/pull/33940)
10190 This hasher is faster, but is believed to provide sufficient
10191 protection from collision attacks.
10192* [Comparison of `Ipv4Addr` is 10x faster](https://github.com/rust-lang/rust/pull/33891)
10193
10194Rustdoc
10195-------
10196
10197* [Fix empty implementation section on some module pages](https://github.com/rust-lang/rust/pull/34536)
10198* [Fix inlined renamed re-exports in import lists](https://github.com/rust-lang/rust/pull/34479)
10199* [Fix search result layout for enum variants and struct fields](https://github.com/rust-lang/rust/pull/34477)
10200* [Fix issues with source links to external crates](https://github.com/rust-lang/rust/pull/34387)
10201* [Fix redirect pages for renamed re-exports](https://github.com/rust-lang/rust/pull/34245)
10202
10203Tooling
10204-------
10205
10206* [rustc is better at finding the MSVC toolchain](https://github.com/rust-lang/rust/pull/34492)
10207* [When emitting debug info, rustc emits frame pointers for closures,
10208 shims and glue, as it does for all other functions](https://github.com/rust-lang/rust/pull/33909)
10209* [rust-lldb warns about unsupported versions of LLDB](https://github.com/rust-lang/rust/pull/34646)
10210* Many more errors have been given error codes and extended
10211 explanations
10212* API documentation continues to be improved, with many new examples
10213
10214Misc
10215----
10216
10217* [rustc no longer hangs when dependencies recursively re-export
10218 submodules](https://github.com/rust-lang/rust/pull/34542)
10219* [rustc requires LLVM 3.7+](https://github.com/rust-lang/rust/pull/34104)
10220* [The 'How Safe and Unsafe Interact' chapter of The Rustonomicon was
10221 rewritten](https://github.com/rust-lang/rust/pull/33895)
10222* [rustc support 16-bit pointer sizes](https://github.com/rust-lang/rust/pull/33460).
10223 No targets use this yet, but it works toward AVR support.
10224
10225Compatibility Notes
10226-------------------
10227
10228* [`const`s and `static`s may not have unsized types](https://github.com/rust-lang/rust/pull/34443)
10229* [The new follow-set rules that place restrictions on `macro_rules!`
10230 in order to ensure syntax forward-compatibility have been enabled](https://github.com/rust-lang/rust/pull/33982)
10231 This was an [amendment to RFC 550](https://github.com/rust-lang/rfcs/pull/1384),
10232 and has been a warning since 1.10.
10233* [`cfg` attribute process has been refactored to fix various bugs](https://github.com/rust-lang/rust/pull/33706).
10234 This causes breakage in some corner cases.
10235
10236
10237Version 1.10.0 (2016-07-07)
10238===========================
10239
10240Language
10241--------
10242
10243* [`Copy` types are required to have a trivial implementation of `Clone`](https://github.com/rust-lang/rust/pull/33420).
10244 [RFC 1521](https://github.com/rust-lang/rfcs/blob/master/text/1521-copy-clone-semantics.md).
10245* [Single-variant enums support the `#[repr(..)]` attribute](https://github.com/rust-lang/rust/pull/33355).
10246* [Fix `#[derive(RustcEncodable)]` in the presence of other `encode` methods](https://github.com/rust-lang/rust/pull/32908).
10247* [`panic!` can be converted to a runtime abort with the
10248 `-C panic=abort` flag](https://github.com/rust-lang/rust/pull/32900).
10249 [RFC 1513](https://github.com/rust-lang/rfcs/blob/master/text/1513-less-unwinding.md).
10250* [Add a new crate type, 'cdylib'](https://github.com/rust-lang/rust/pull/33553).
10251 cdylibs are dynamic libraries suitable for loading by non-Rust hosts.
10252 [RFC 1510](https://github.com/rust-lang/rfcs/blob/master/text/1510-cdylib.md).
10253 Note that Cargo does not yet directly support cdylibs.
10254
10255Stabilized APIs
10256---------------
10257
10258* `os::windows::fs::OpenOptionsExt::access_mode`
10259* `os::windows::fs::OpenOptionsExt::share_mode`
10260* `os::windows::fs::OpenOptionsExt::custom_flags`
10261* `os::windows::fs::OpenOptionsExt::attributes`
10262* `os::windows::fs::OpenOptionsExt::security_qos_flags`
10263* `os::unix::fs::OpenOptionsExt::custom_flags`
10264* [`sync::Weak::new`](http://doc.rust-lang.org/alloc/arc/struct.Weak.html#method.new)
10265* `Default for sync::Weak`
10266* [`panic::set_hook`](http://doc.rust-lang.org/std/panic/fn.set_hook.html)
10267* [`panic::take_hook`](http://doc.rust-lang.org/std/panic/fn.take_hook.html)
10268* [`panic::PanicInfo`](http://doc.rust-lang.org/std/panic/struct.PanicInfo.html)
10269* [`panic::PanicInfo::payload`](http://doc.rust-lang.org/std/panic/struct.PanicInfo.html#method.payload)
10270* [`panic::PanicInfo::location`](http://doc.rust-lang.org/std/panic/struct.PanicInfo.html#method.location)
10271* [`panic::Location`](http://doc.rust-lang.org/std/panic/struct.Location.html)
10272* [`panic::Location::file`](http://doc.rust-lang.org/std/panic/struct.Location.html#method.file)
10273* [`panic::Location::line`](http://doc.rust-lang.org/std/panic/struct.Location.html#method.line)
10274* [`ffi::CStr::from_bytes_with_nul`](http://doc.rust-lang.org/std/ffi/struct.CStr.html#method.from_bytes_with_nul)
10275* [`ffi::CStr::from_bytes_with_nul_unchecked`](http://doc.rust-lang.org/std/ffi/struct.CStr.html#method.from_bytes_with_nul_unchecked)
10276* [`ffi::FromBytesWithNulError`](http://doc.rust-lang.org/std/ffi/struct.FromBytesWithNulError.html)
10277* [`fs::Metadata::modified`](http://doc.rust-lang.org/std/fs/struct.Metadata.html#method.modified)
10278* [`fs::Metadata::accessed`](http://doc.rust-lang.org/std/fs/struct.Metadata.html#method.accessed)
10279* [`fs::Metadata::created`](http://doc.rust-lang.org/std/fs/struct.Metadata.html#method.created)
10280* `sync::atomic::Atomic{Usize,Isize,Bool,Ptr}::compare_exchange`
10281* `sync::atomic::Atomic{Usize,Isize,Bool,Ptr}::compare_exchange_weak`
10282* `collections::{btree,hash}_map::{Occupied,Vacant,}Entry::key`
10283* `os::unix::net::{UnixStream, UnixListener, UnixDatagram, SocketAddr}`
10284* [`SocketAddr::is_unnamed`](http://doc.rust-lang.org/std/os/unix/net/struct.SocketAddr.html#method.is_unnamed)
10285* [`SocketAddr::as_pathname`](http://doc.rust-lang.org/std/os/unix/net/struct.SocketAddr.html#method.as_pathname)
10286* [`UnixStream::connect`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixStream.html#method.connect)
10287* [`UnixStream::pair`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixStream.html#method.pair)
10288* [`UnixStream::try_clone`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixStream.html#method.try_clone)
10289* [`UnixStream::local_addr`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixStream.html#method.local_addr)
10290* [`UnixStream::peer_addr`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixStream.html#method.peer_addr)
10291* [`UnixStream::set_read_timeout`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixStream.html#method.read_timeout)
10292* [`UnixStream::set_write_timeout`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixStream.html#method.write_timeout)
10293* [`UnixStream::read_timeout`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixStream.html#method.read_timeout)
10294* [`UnixStream::write_timeout`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixStream.html#method.write_timeout)
10295* [`UnixStream::set_nonblocking`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixStream.html#method.set_nonblocking)
10296* [`UnixStream::take_error`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixStream.html#method.take_error)
10297* [`UnixStream::shutdown`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixStream.html#method.shutdown)
10298* Read/Write/RawFd impls for `UnixStream`
10299* [`UnixListener::bind`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixListener.html#method.bind)
10300* [`UnixListener::accept`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixListener.html#method.accept)
10301* [`UnixListener::try_clone`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixListener.html#method.try_clone)
10302* [`UnixListener::local_addr`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixListener.html#method.local_addr)
10303* [`UnixListener::set_nonblocking`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixListener.html#method.set_nonblocking)
10304* [`UnixListener::take_error`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixListener.html#method.take_error)
10305* [`UnixListener::incoming`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixListener.html#method.incoming)
10306* RawFd impls for `UnixListener`
10307* [`UnixDatagram::bind`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.bind)
10308* [`UnixDatagram::unbound`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.unbound)
10309* [`UnixDatagram::pair`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.pair)
10310* [`UnixDatagram::connect`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.connect)
10311* [`UnixDatagram::try_clone`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.try_clone)
10312* [`UnixDatagram::local_addr`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.local_addr)
10313* [`UnixDatagram::peer_addr`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.peer_addr)
10314* [`UnixDatagram::recv_from`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.recv_from)
10315* [`UnixDatagram::recv`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.recv)
10316* [`UnixDatagram::send_to`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.send_to)
10317* [`UnixDatagram::send`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.send)
10318* [`UnixDatagram::set_read_timeout`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.set_read_timeout)
10319* [`UnixDatagram::set_write_timeout`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.set_write_timeout)
10320* [`UnixDatagram::read_timeout`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.read_timeout)
10321* [`UnixDatagram::write_timeout`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.write_timeout)
10322* [`UnixDatagram::set_nonblocking`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.set_nonblocking)
10323* [`UnixDatagram::take_error`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.take_error)
10324* [`UnixDatagram::shutdown`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.shutdown)
10325* RawFd impls for `UnixDatagram`
10326* `{BTree,Hash}Map::values_mut`
10327* [`<[_]>::binary_search_by_key`](http://doc.rust-lang.org/std/primitive.slice.html#method.binary_search_by_key)
10328
10329Libraries
10330---------
10331
10332* [The `abs_sub` method of floats is deprecated](https://github.com/rust-lang/rust/pull/33664).
10333 The semantics of this minor method are subtle and probably not what
10334 most people want.
10335* [Add implementation of Ord for Cell<T> and RefCell<T> where T: Ord](https://github.com/rust-lang/rust/pull/33306).
10336* [On Linux, if `HashMap`s can't be initialized with `getrandom` they
10337 will fall back to `/dev/urandom` temporarily to avoid blocking
10338 during early boot](https://github.com/rust-lang/rust/pull/33086).
10339* [Implemented negation for wrapping numerals](https://github.com/rust-lang/rust/pull/33067).
10340* [Implement `Clone` for `binary_heap::IntoIter`](https://github.com/rust-lang/rust/pull/33050).
10341* [Implement `Display` and `Hash` for `std::num::Wrapping`](https://github.com/rust-lang/rust/pull/33023).
10342* [Add `Default` implementation for `&CStr`, `CString`](https://github.com/rust-lang/rust/pull/32990).
10343* [Implement `From<Vec<T>>` and `Into<Vec<T>>` for `VecDeque<T>`](https://github.com/rust-lang/rust/pull/32866).
10344* [Implement `Default` for `UnsafeCell`, `fmt::Error`, `Condvar`,
10345 `Mutex`, `RwLock`](https://github.com/rust-lang/rust/pull/32785).
10346
10347Cargo
10348-----
10349* [Cargo.toml supports the `profile.*.panic` option](https://github.com/rust-lang/cargo/pull/2687).
10350 This controls the runtime behavior of the `panic!` macro
10351 and can be either "unwind" (the default), or "abort".
10352 [RFC 1513](https://github.com/rust-lang/rfcs/blob/master/text/1513-less-unwinding.md).
10353* [Don't throw away errors with `-p` arguments](https://github.com/rust-lang/cargo/pull/2723).
10354* [Report status to stderr instead of stdout](https://github.com/rust-lang/cargo/pull/2693).
10355* [Build scripts are passed a `CARGO_MANIFEST_LINKS` environment
10356 variable that corresponds to the `links` field of the manifest](https://github.com/rust-lang/cargo/pull/2710).
10357* [Ban keywords from crate names](https://github.com/rust-lang/cargo/pull/2707).
10358* [Canonicalize `CARGO_HOME` on Windows](https://github.com/rust-lang/cargo/pull/2604).
10359* [Retry network requests](https://github.com/rust-lang/cargo/pull/2396).
10360 By default they are retried twice, which can be customized with the
10361 `net.retry` value in `.cargo/config`.
10362* [Don't print extra error info for failing subcommands](https://github.com/rust-lang/cargo/pull/2674).
10363* [Add `--force` flag to `cargo install`](https://github.com/rust-lang/cargo/pull/2405).
10364* [Don't use `flock` on NFS mounts](https://github.com/rust-lang/cargo/pull/2623).
10365* [Prefer building `cargo install` artifacts in temporary directories](https://github.com/rust-lang/cargo/pull/2610).
10366 Makes it possible to install multiple crates in parallel.
10367* [Add `cargo test --doc`](https://github.com/rust-lang/cargo/pull/2578).
10368* [Add `cargo --explain`](https://github.com/rust-lang/cargo/pull/2551).
10369* [Don't print warnings when `-q` is passed](https://github.com/rust-lang/cargo/pull/2576).
10370* [Add `cargo doc --lib` and `--bin`](https://github.com/rust-lang/cargo/pull/2577).
10371* [Don't require build script output to be UTF-8](https://github.com/rust-lang/cargo/pull/2560).
10372* [Correctly attempt multiple git usernames](https://github.com/rust-lang/cargo/pull/2584).
10373
10374Performance
10375-----------
10376
10377* [rustc memory usage was reduced by refactoring the context used for
10378 type checking](https://github.com/rust-lang/rust/pull/33425).
10379* [Speed up creation of `HashMap`s by caching the random keys used
10380 to initialize the hash state](https://github.com/rust-lang/rust/pull/33318).
10381* [The `find` implementation for `Chain` iterators is 2x faster](https://github.com/rust-lang/rust/pull/33289).
10382* [Trait selection optimizations speed up type checking by 15%](https://github.com/rust-lang/rust/pull/33138).
10383* [Efficient trie lookup for boolean Unicode properties](https://github.com/rust-lang/rust/pull/33098).
10384 10x faster than the previous lookup tables.
10385* [Special case `#[derive(Copy, Clone)]` to avoid bloat](https://github.com/rust-lang/rust/pull/31414).
10386
10387Usability
10388---------
10389
10390* Many incremental improvements to documentation and rustdoc.
10391* [rustdoc: List blanket trait impls](https://github.com/rust-lang/rust/pull/33514).
10392* [rustdoc: Clean up ABI rendering](https://github.com/rust-lang/rust/pull/33151).
10393* [Indexing with the wrong type produces a more informative error](https://github.com/rust-lang/rust/pull/33401).
10394* [Improve diagnostics for constants being used in irrefutable patterns](https://github.com/rust-lang/rust/pull/33406).
10395* [When many method candidates are in scope limit the suggestions to 10](https://github.com/rust-lang/rust/pull/33338).
10396* [Remove confusing suggestion when calling a `fn` type](https://github.com/rust-lang/rust/pull/33325).
10397* [Do not suggest changing `&mut self` to `&mut mut self`](https://github.com/rust-lang/rust/pull/33319).
10398
10399Misc
10400----
10401
10402* [Update i686-linux-android features to match Android ABI](https://github.com/rust-lang/rust/pull/33651).
10403* [Update aarch64-linux-android features to match Android ABI](https://github.com/rust-lang/rust/pull/33500).
10404* [`std` no longer prints backtraces on platforms where the running
10405 module must be loaded with `env::current_exe`, which can't be relied
10406 on](https://github.com/rust-lang/rust/pull/33554).
10407* This release includes std binaries for the i586-unknown-linux-gnu,
10408 i686-unknown-linux-musl, and armv7-linux-androideabi targets. The
10409 i586 target is for old x86 hardware without SSE2, and the armv7
10410 target is for Android running on modern ARM architectures.
10411* [The `rust-gdb` and `rust-lldb` scripts are distributed on all
10412 Unix platforms](https://github.com/rust-lang/rust/pull/32835).
10413* [On Unix the runtime aborts by calling `libc::abort` instead of
10414 generating an illegal instruction](https://github.com/rust-lang/rust/pull/31457).
10415* [Rust is now bootstrapped from the previous release of Rust,
10416 instead of a snapshot from an arbitrary commit](https://github.com/rust-lang/rust/pull/32942).
10417
10418Compatibility Notes
10419-------------------
10420
10421* [`AtomicBool` is now bool-sized, not word-sized](https://github.com/rust-lang/rust/pull/33579).
10422* [`target_env` for Linux ARM targets is just `gnu`, not
10423 `gnueabihf`, `gnueabi`, etc](https://github.com/rust-lang/rust/pull/33403).
10424* [Consistently panic on overflow in `Duration::new`](https://github.com/rust-lang/rust/pull/33072).
10425* [Change `String::truncate` to panic less](https://github.com/rust-lang/rust/pull/32977).
10426* [Add `:block` to the follow set for `:ty` and `:path`](https://github.com/rust-lang/rust/pull/32945).
10427 Affects how macros are parsed.
10428* [Fix macro hygiene bug](https://github.com/rust-lang/rust/pull/32923).
10429* [Feature-gated attributes on macro-generated macro invocations are
10430 now rejected](https://github.com/rust-lang/rust/pull/32791).
10431* [Suppress fallback and ambiguity errors during type inference](https://github.com/rust-lang/rust/pull/32258).
10432 This caused some minor changes to type inference.
10433
10434
10435Version 1.9.0 (2016-05-26)
10436==========================
10437
10438Language
10439--------
10440
10441* The `#[deprecated]` attribute when applied to an API will generate
10442 warnings when used. The warnings may be suppressed with
10443 `#[allow(deprecated)]`. [RFC 1270].
10444* [`fn` item types are zero sized, and each `fn` names a unique
10445 type][1.9fn]. This will break code that transmutes `fn`s, so calling
10446 `transmute` on a `fn` type will generate a warning for a few cycles,
10447 then will be converted to an error.
10448* [Field and method resolution understand visibility, so private
10449 fields and methods cannot prevent the proper use of public fields
10450 and methods][1.9fv].
10451* [The parser considers unicode codepoints in the
10452 `PATTERN_WHITE_SPACE` category to be whitespace][1.9ws].
10453
10454Stabilized APIs
10455---------------
10456
10457* [`std::panic`]
10458* [`std::panic::catch_unwind`] (renamed from `recover`)
10459* [`std::panic::resume_unwind`] (renamed from `propagate`)
10460* [`std::panic::AssertUnwindSafe`] (renamed from `AssertRecoverSafe`)
10461* [`std::panic::UnwindSafe`] (renamed from `RecoverSafe`)
10462* [`str::is_char_boundary`]
10463* [`<*const T>::as_ref`]
10464* [`<*mut T>::as_ref`]
10465* [`<*mut T>::as_mut`]
10466* [`AsciiExt::make_ascii_uppercase`]
10467* [`AsciiExt::make_ascii_lowercase`]
10468* [`char::decode_utf16`]
10469* [`char::DecodeUtf16`]
10470* [`char::DecodeUtf16Error`]
10471* [`char::DecodeUtf16Error::unpaired_surrogate`]
10472* [`BTreeSet::take`]
10473* [`BTreeSet::replace`]
10474* [`BTreeSet::get`]
10475* [`HashSet::take`]
10476* [`HashSet::replace`]
10477* [`HashSet::get`]
10478* [`OsString::with_capacity`]
10479* [`OsString::clear`]
10480* [`OsString::capacity`]
10481* [`OsString::reserve`]
10482* [`OsString::reserve_exact`]
10483* [`OsStr::is_empty`]
10484* [`OsStr::len`]
10485* [`std::os::unix::thread`]
10486* [`RawPthread`]
10487* [`JoinHandleExt`]
10488* [`JoinHandleExt::as_pthread_t`]
10489* [`JoinHandleExt::into_pthread_t`]
10490* [`HashSet::hasher`]
10491* [`HashMap::hasher`]
10492* [`CommandExt::exec`]
10493* [`File::try_clone`]
10494* [`SocketAddr::set_ip`]
10495* [`SocketAddr::set_port`]
10496* [`SocketAddrV4::set_ip`]
10497* [`SocketAddrV4::set_port`]
10498* [`SocketAddrV6::set_ip`]
10499* [`SocketAddrV6::set_port`]
10500* [`SocketAddrV6::set_flowinfo`]
10501* [`SocketAddrV6::set_scope_id`]
10502* [`slice::copy_from_slice`]
10503* [`ptr::read_volatile`]
10504* [`ptr::write_volatile`]
10505* [`OpenOptions::create_new`]
10506* [`TcpStream::set_nodelay`]
10507* [`TcpStream::nodelay`]
10508* [`TcpStream::set_ttl`]
10509* [`TcpStream::ttl`]
10510* [`TcpStream::set_only_v6`]
10511* [`TcpStream::only_v6`]
10512* [`TcpStream::take_error`]
10513* [`TcpStream::set_nonblocking`]
10514* [`TcpListener::set_ttl`]
10515* [`TcpListener::ttl`]
10516* [`TcpListener::set_only_v6`]
10517* [`TcpListener::only_v6`]
10518* [`TcpListener::take_error`]
10519* [`TcpListener::set_nonblocking`]
10520* [`UdpSocket::set_broadcast`]
10521* [`UdpSocket::broadcast`]
10522* [`UdpSocket::set_multicast_loop_v4`]
10523* [`UdpSocket::multicast_loop_v4`]
10524* [`UdpSocket::set_multicast_ttl_v4`]
10525* [`UdpSocket::multicast_ttl_v4`]
10526* [`UdpSocket::set_multicast_loop_v6`]
10527* [`UdpSocket::multicast_loop_v6`]
10528* [`UdpSocket::set_multicast_ttl_v6`]
10529* [`UdpSocket::multicast_ttl_v6`]
10530* [`UdpSocket::set_ttl`]
10531* [`UdpSocket::ttl`]
10532* [`UdpSocket::set_only_v6`]
10533* [`UdpSocket::only_v6`]
10534* [`UdpSocket::join_multicast_v4`]
10535* [`UdpSocket::join_multicast_v6`]
10536* [`UdpSocket::leave_multicast_v4`]
10537* [`UdpSocket::leave_multicast_v6`]
10538* [`UdpSocket::take_error`]
10539* [`UdpSocket::connect`]
10540* [`UdpSocket::send`]
10541* [`UdpSocket::recv`]
10542* [`UdpSocket::set_nonblocking`]
10543
10544Libraries
10545---------
10546
10547* [`std::sync::Once` is poisoned if its initialization function
10548 fails][1.9o].
10549* [`cell::Ref` and `cell::RefMut` can contain unsized types][1.9cu].
10550* [Most types implement `fmt::Debug`][1.9db].
10551* [The default buffer size used by `BufReader` and `BufWriter` was
10552 reduced to 8K, from 64K][1.9bf]. This is in line with the buffer size
10553 used by other languages.
10554* [`Instant`, `SystemTime` and `Duration` implement `+=` and `-=`.
10555 `Duration` additionally implements `*=` and `/=`][1.9ta].
10556* [`Skip` is a `DoubleEndedIterator`][1.9sk].
10557* [`From<[u8; 4]>` is implemented for `Ipv4Addr`][1.9fi].
10558* [`Chain` implements `BufRead`][1.9ch].
10559* [`HashMap`, `HashSet` and iterators are covariant][1.9hc].
10560
10561Cargo
10562-----
10563
10564* [Cargo can now run concurrently][1.9cc].
10565* [Top-level overrides allow specific revisions of crates to be
10566 overridden through the entire crate graph][1.9ct]. This is intended
10567 to make upgrades easier for large projects, by allowing crates to be
10568 forked temporarily until they've been upgraded and republished.
10569* [Cargo exports a `CARGO_PKG_AUTHORS` environment variable][1.9cp].
10570* [Cargo will pass the contents of the `RUSTFLAGS` variable to `rustc`
10571 on the commandline][1.9cf]. `rustc` arguments can also be specified
10572 in the `build.rustflags` configuration key.
10573
10574Performance
10575-----------
10576
10577* [The time complexity of comparing variables for equivalence during type
10578 unification is reduced from _O_(_n_!) to _O_(_n_)][1.9tu]. This leads
10579 to major compilation time improvement in some scenarios.
10580* [`ToString` is specialized for `str`, giving it the same performance
10581 as `to_owned`][1.9ts].
10582* [Spawning processes with `Command::output` no longer creates extra
10583 threads][1.9sp].
10584* [`#[derive(PartialEq)]` and `#[derive(PartialOrd)]` emit less code
10585 for C-like enums][1.9cl].
10586
10587Misc
10588----
10589
10590* [Passing the `--quiet` flag to a test runner will produce
10591 much-abbreviated output][1.9q].
10592* The Rust Project now publishes std binaries for the
10593 `mips-unknown-linux-musl`, `mipsel-unknown-linux-musl`, and
10594 `i586-pc-windows-msvc` targets.
10595
10596Compatibility Notes
10597-------------------
10598
10599* [`std::sync::Once` is poisoned if its initialization function
10600 fails][1.9o].
10601* [It is illegal to define methods with the same name in overlapping
10602 inherent `impl` blocks][1.9sn].
10603* [`fn` item types are zero sized, and each `fn` names a unique
10604 type][1.9fn]. This will break code that transmutes `fn`s, so calling
10605 `transmute` on a `fn` type will generate a warning for a few cycles,
10606 then will be converted to an error.
10607* [Improvements to const evaluation may trigger new errors when integer
10608 literals are out of range][1.9ce].
10609
10610
10611[1.9bf]: https://github.com/rust-lang/rust/pull/32695
10612[1.9cc]: https://github.com/rust-lang/cargo/pull/2486
10613[1.9ce]: https://github.com/rust-lang/rust/pull/30587
10614[1.9cf]: https://github.com/rust-lang/cargo/pull/2241
10615[1.9ch]: https://github.com/rust-lang/rust/pull/32541
10616[1.9cl]: https://github.com/rust-lang/rust/pull/31977
10617[1.9cp]: https://github.com/rust-lang/cargo/pull/2465
10618[1.9ct]: https://github.com/rust-lang/cargo/pull/2385
10619[1.9cu]: https://github.com/rust-lang/rust/pull/32652
10620[1.9db]: https://github.com/rust-lang/rust/pull/32054
10621[1.9fi]: https://github.com/rust-lang/rust/pull/32050
10622[1.9fn]: https://github.com/rust-lang/rust/pull/31710
10623[1.9fv]: https://github.com/rust-lang/rust/pull/31938
10624[1.9hc]: https://github.com/rust-lang/rust/pull/32635
10625[1.9o]: https://github.com/rust-lang/rust/pull/32325
10626[1.9q]: https://github.com/rust-lang/rust/pull/31887
10627[1.9sk]: https://github.com/rust-lang/rust/pull/31700
10628[1.9sn]: https://github.com/rust-lang/rust/pull/31925
10629[1.9sp]: https://github.com/rust-lang/rust/pull/31618
10630[1.9ta]: https://github.com/rust-lang/rust/pull/32448
10631[1.9ts]: https://github.com/rust-lang/rust/pull/32586
10632[1.9tu]: https://github.com/rust-lang/rust/pull/32062
10633[1.9ws]: https://github.com/rust-lang/rust/pull/29734
10634[RFC 1270]: https://github.com/rust-lang/rfcs/blob/master/text/1270-deprecation.md
10635[`<*const T>::as_ref`]: http://doc.rust-lang.org/nightly/std/primitive.pointer.html#method.as_ref
10636[`<*mut T>::as_mut`]: http://doc.rust-lang.org/nightly/std/primitive.pointer.html#method.as_mut
10637[`<*mut T>::as_ref`]: http://doc.rust-lang.org/nightly/std/primitive.pointer.html#method.as_ref
10638[`slice::copy_from_slice`]: http://doc.rust-lang.org/nightly/std/primitive.slice.html#method.copy_from_slice
10639[`AsciiExt::make_ascii_lowercase`]: http://doc.rust-lang.org/nightly/std/ascii/trait.AsciiExt.html#tymethod.make_ascii_lowercase
10640[`AsciiExt::make_ascii_uppercase`]: http://doc.rust-lang.org/nightly/std/ascii/trait.AsciiExt.html#tymethod.make_ascii_uppercase
10641[`BTreeSet::get`]: http://doc.rust-lang.org/nightly/collections/btree/set/struct.BTreeSet.html#method.get
10642[`BTreeSet::replace`]: http://doc.rust-lang.org/nightly/collections/btree/set/struct.BTreeSet.html#method.replace
10643[`BTreeSet::take`]: http://doc.rust-lang.org/nightly/collections/btree/set/struct.BTreeSet.html#method.take
10644[`CommandExt::exec`]: http://doc.rust-lang.org/nightly/std/os/unix/process/trait.CommandExt.html#tymethod.exec
10645[`File::try_clone`]: http://doc.rust-lang.org/nightly/std/fs/struct.File.html#method.try_clone
10646[`HashMap::hasher`]: http://doc.rust-lang.org/nightly/std/collections/struct.HashMap.html#method.hasher
10647[`HashSet::get`]: http://doc.rust-lang.org/nightly/std/collections/struct.HashSet.html#method.get
10648[`HashSet::hasher`]: http://doc.rust-lang.org/nightly/std/collections/struct.HashSet.html#method.hasher
10649[`HashSet::replace`]: http://doc.rust-lang.org/nightly/std/collections/struct.HashSet.html#method.replace
10650[`HashSet::take`]: http://doc.rust-lang.org/nightly/std/collections/struct.HashSet.html#method.take
10651[`JoinHandleExt::as_pthread_t`]: http://doc.rust-lang.org/nightly/std/os/unix/thread/trait.JoinHandleExt.html#tymethod.as_pthread_t
10652[`JoinHandleExt::into_pthread_t`]: http://doc.rust-lang.org/nightly/std/os/unix/thread/trait.JoinHandleExt.html#tymethod.into_pthread_t
10653[`JoinHandleExt`]: http://doc.rust-lang.org/nightly/std/os/unix/thread/trait.JoinHandleExt.html
10654[`OpenOptions::create_new`]: http://doc.rust-lang.org/nightly/std/fs/struct.OpenOptions.html#method.create_new
10655[`OsStr::is_empty`]: http://doc.rust-lang.org/nightly/std/ffi/struct.OsStr.html#method.is_empty
10656[`OsStr::len`]: http://doc.rust-lang.org/nightly/std/ffi/struct.OsStr.html#method.len
10657[`OsString::capacity`]: http://doc.rust-lang.org/nightly/std/ffi/struct.OsString.html#method.capacity
10658[`OsString::clear`]: http://doc.rust-lang.org/nightly/std/ffi/struct.OsString.html#method.clear
10659[`OsString::reserve_exact`]: http://doc.rust-lang.org/nightly/std/ffi/struct.OsString.html#method.reserve_exact
10660[`OsString::reserve`]: http://doc.rust-lang.org/nightly/std/ffi/struct.OsString.html#method.reserve
10661[`OsString::with_capacity`]: http://doc.rust-lang.org/nightly/std/ffi/struct.OsString.html#method.with_capacity
10662[`RawPthread`]: http://doc.rust-lang.org/nightly/std/os/unix/thread/type.RawPthread.html
10663[`SocketAddr::set_ip`]: http://doc.rust-lang.org/nightly/std/net/enum.SocketAddr.html#method.set_ip
10664[`SocketAddr::set_port`]: http://doc.rust-lang.org/nightly/std/net/enum.SocketAddr.html#method.set_port
10665[`SocketAddrV4::set_ip`]: http://doc.rust-lang.org/nightly/std/net/struct.SocketAddrV4.html#method.set_ip
10666[`SocketAddrV4::set_port`]: http://doc.rust-lang.org/nightly/std/net/struct.SocketAddrV4.html#method.set_port
10667[`SocketAddrV6::set_flowinfo`]: http://doc.rust-lang.org/nightly/std/net/struct.SocketAddrV6.html#method.set_flowinfo
10668[`SocketAddrV6::set_ip`]: http://doc.rust-lang.org/nightly/std/net/struct.SocketAddrV6.html#method.set_ip
10669[`SocketAddrV6::set_port`]: http://doc.rust-lang.org/nightly/std/net/struct.SocketAddrV6.html#method.set_port
10670[`SocketAddrV6::set_scope_id`]: http://doc.rust-lang.org/nightly/std/net/struct.SocketAddrV6.html#method.set_scope_id
10671[`TcpListener::only_v6`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.only_v6
10672[`TcpListener::set_nonblocking`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.set_nonblocking
10673[`TcpListener::set_only_v6`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.set_only_v6
10674[`TcpListener::set_ttl`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.set_ttl
10675[`TcpListener::take_error`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.take_error
10676[`TcpListener::ttl`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.ttl
10677[`TcpStream::nodelay`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.nodelay
10678[`TcpStream::only_v6`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.only_v6
10679[`TcpStream::set_nodelay`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.set_nodelay
10680[`TcpStream::set_nonblocking`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.set_nonblocking
10681[`TcpStream::set_only_v6`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.set_only_v6
10682[`TcpStream::set_ttl`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.set_ttl
10683[`TcpStream::take_error`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.take_error
10684[`TcpStream::ttl`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.ttl
10685[`UdpSocket::broadcast`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.broadcast
10686[`UdpSocket::connect`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.connect
10687[`UdpSocket::join_multicast_v4`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.join_multicast_v4
10688[`UdpSocket::join_multicast_v6`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.join_multicast_v6
10689[`UdpSocket::leave_multicast_v4`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.leave_multicast_v4
10690[`UdpSocket::leave_multicast_v6`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.leave_multicast_v6
10691[`UdpSocket::multicast_loop_v4`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.multicast_loop_v4
10692[`UdpSocket::multicast_loop_v6`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.multicast_loop_v6
10693[`UdpSocket::multicast_ttl_v4`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.multicast_ttl_v4
10694[`UdpSocket::multicast_ttl_v6`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.multicast_ttl_v6
10695[`UdpSocket::only_v6`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.only_v6
10696[`UdpSocket::recv`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.recv
10697[`UdpSocket::send`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.send
10698[`UdpSocket::set_broadcast`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.set_broadcast
10699[`UdpSocket::set_multicast_loop_v4`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.set_multicast_loop_v4
10700[`UdpSocket::set_multicast_loop_v6`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.set_multicast_loop_v6
10701[`UdpSocket::set_multicast_ttl_v4`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.set_multicast_ttl_v4
10702[`UdpSocket::set_multicast_ttl_v6`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.set_multicast_ttl_v6
10703[`UdpSocket::set_nonblocking`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.set_nonblocking
10704[`UdpSocket::set_only_v6`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.set_only_v6
10705[`UdpSocket::set_ttl`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.set_ttl
10706[`UdpSocket::take_error`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.take_error
10707[`UdpSocket::ttl`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.ttl
10708[`char::DecodeUtf16Error::unpaired_surrogate`]: http://doc.rust-lang.org/nightly/std/char/struct.DecodeUtf16Error.html#method.unpaired_surrogate
10709[`char::DecodeUtf16Error`]: http://doc.rust-lang.org/nightly/std/char/struct.DecodeUtf16Error.html
10710[`char::DecodeUtf16`]: http://doc.rust-lang.org/nightly/std/char/struct.DecodeUtf16.html
10711[`char::decode_utf16`]: http://doc.rust-lang.org/nightly/std/char/fn.decode_utf16.html
10712[`ptr::read_volatile`]: http://doc.rust-lang.org/nightly/std/ptr/fn.read_volatile.html
10713[`ptr::write_volatile`]: http://doc.rust-lang.org/nightly/std/ptr/fn.write_volatile.html
10714[`std::os::unix::thread`]: http://doc.rust-lang.org/nightly/std/os/unix/thread/index.html
10715[`std::panic::AssertUnwindSafe`]: http://doc.rust-lang.org/nightly/std/panic/struct.AssertUnwindSafe.html
10716[`std::panic::UnwindSafe`]: http://doc.rust-lang.org/nightly/std/panic/trait.UnwindSafe.html
10717[`std::panic::catch_unwind`]: http://doc.rust-lang.org/nightly/std/panic/fn.catch_unwind.html
10718[`std::panic::resume_unwind`]: http://doc.rust-lang.org/nightly/std/panic/fn.resume_unwind.html
10719[`std::panic`]: http://doc.rust-lang.org/nightly/std/panic/index.html
10720[`str::is_char_boundary`]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.is_char_boundary
10721
10722
10723Version 1.8.0 (2016-04-14)
10724==========================
10725
10726Language
10727--------
10728
10729* Rust supports overloading of compound assignment statements like
10730 `+=` by implementing the [`AddAssign`], [`SubAssign`],
10731 [`MulAssign`], [`DivAssign`], [`RemAssign`], [`BitAndAssign`],
10732 [`BitOrAssign`], [`BitXorAssign`], [`ShlAssign`], or [`ShrAssign`]
10733 traits. [RFC 953].
10734* Empty structs can be defined with braces, as in `struct Foo { }`, in
10735 addition to the non-braced form, `struct Foo;`. [RFC 218].
10736
10737Libraries
10738---------
10739
10740* Stabilized APIs:
10741 * [`str::encode_utf16`] (renamed from `utf16_units`)
10742 * [`str::EncodeUtf16`] (renamed from `Utf16Units`)
10743 * [`Ref::map`]
10744 * [`RefMut::map`]
10745 * [`ptr::drop_in_place`]
10746 * [`time::Instant`]
10747 * [`time::SystemTime`]
10748 * [`Instant::now`]
10749 * [`Instant::duration_since`] (renamed from `duration_from_earlier`)
10750 * [`Instant::elapsed`]
10751 * [`SystemTime::now`]
10752 * [`SystemTime::duration_since`] (renamed from `duration_from_earlier`)
10753 * [`SystemTime::elapsed`]
10754 * Various `Add`/`Sub` impls for `Time` and `SystemTime`
10755 * [`SystemTimeError`]
10756 * [`SystemTimeError::duration`]
10757 * Various impls for `SystemTimeError`
10758 * [`UNIX_EPOCH`]
10759 * [`AddAssign`], [`SubAssign`], [`MulAssign`], [`DivAssign`],
10760 [`RemAssign`], [`BitAndAssign`], [`BitOrAssign`],
10761 [`BitXorAssign`], [`ShlAssign`], [`ShrAssign`].
10762* [The `write!` and `writeln!` macros correctly emit errors if any of
10763 their arguments can't be formatted][1.8w].
10764* [Various I/O functions support large files on 32-bit Linux][1.8l].
10765* [The Unix-specific `raw` modules, which contain a number of
10766 redefined C types are deprecated][1.8r], including `os::raw::unix`,
10767 `os::raw::macos`, and `os::raw::linux`. These modules defined types
10768 such as `ino_t` and `dev_t`. The inconsistency of these definitions
10769 across platforms was making it difficult to implement `std`
10770 correctly. Those that need these definitions should use the `libc`
10771 crate. [RFC 1415].
10772* The Unix-specific `MetadataExt` traits, including
10773 `os::unix::fs::MetadataExt`, which expose values such as inode
10774 numbers [no longer return platform-specific types][1.8r], but
10775 instead return widened integers. [RFC 1415].
10776* [`btree_set::{IntoIter, Iter, Range}` are covariant][1.8cv].
10777* [Atomic loads and stores are not volatile][1.8a].
10778* [All types in `sync::mpsc` implement `fmt::Debug`][1.8mp].
10779
10780Performance
10781-----------
10782
10783* [Inlining hash functions lead to a 3% compile-time improvement in
10784 some workloads][1.8h].
10785* When using jemalloc, its symbols are [unprefixed so that it
10786 overrides the libc malloc implementation][1.8h]. This means that for
10787 rustc, LLVM is now using jemalloc, which results in a 6%
10788 compile-time improvement on a specific workload.
10789* [Avoid quadratic growth in function size due to cleanups][1.8cu].
10790
10791Misc
10792----
10793
10794* [32-bit MSVC builds finally implement unwinding][1.8ms].
10795 i686-pc-windows-msvc is now considered a tier-1 platform.
10796* [The `--print targets` flag prints a list of supported targets][1.8t].
10797* [The `--print cfg` flag prints the `cfg`s defined for the current
10798 target][1.8cf].
10799* [`rustc` can be built with an new Cargo-based build system, written
10800 in Rust][1.8b]. It will eventually replace Rust's Makefile-based
10801 build system. To enable it configure with `configure --rustbuild`.
10802* [Errors for non-exhaustive `match` patterns now list up to 3 missing
10803 variants while also indicating the total number of missing variants
10804 if more than 3][1.8m].
10805* [Executable stacks are disabled on Linux and BSD][1.8nx].
10806* The Rust Project now publishes binary releases of the standard
10807 library for a number of tier-2 targets:
10808 `armv7-unknown-linux-gnueabihf`, `powerpc-unknown-linux-gnu`,
10809 `powerpc64-unknown-linux-gnu`, `powerpc64le-unknown-linux-gnu`
10810 `x86_64-rumprun-netbsd`. These can be installed with
10811 tools such as [multirust][1.8mr].
10812
10813Cargo
10814-----
10815
10816* [`cargo init` creates a new Cargo project in the current
10817 directory][1.8ci]. It is otherwise like `cargo new`.
10818* [Cargo has configuration keys for `-v` and
10819 `--color`][1.8cc]. `verbose` and `color`, respectively, go in the
10820 `[term]` section of `.cargo/config`.
10821* [Configuration keys that evaluate to strings or integers can be set
10822 via environment variables][1.8ce]. For example the `build.jobs` key
10823 can be set via `CARGO_BUILD_JOBS`. Environment variables take
10824 precedence over config files.
10825* [Target-specific dependencies support Rust `cfg` syntax for
10826 describing targets][1.8cfg] so that dependencies for multiple
10827 targets can be specified together. [RFC 1361].
10828* [The environment variables `CARGO_TARGET_ROOT`, `RUSTC`, and
10829 `RUSTDOC` take precedence over the `build.target-dir`,
10830 `build.rustc`, and `build.rustdoc` configuration values][1.8cfv].
10831* [The child process tree is killed on Windows when Cargo is
10832 killed][1.8ck].
10833* [The `build.target` configuration value sets the target platform,
10834 like `--target`][1.8ct].
10835
10836Compatibility Notes
10837-------------------
10838
10839* [Unstable compiler flags have been further restricted][1.8u]. Since
10840 1.0 `-Z` flags have been considered unstable, and other flags that
10841 were considered unstable additionally required passing `-Z
10842 unstable-options` to access. Unlike unstable language and library
10843 features though, these options have been accessible on the stable
10844 release channel. Going forward, *new unstable flags will not be
10845 available on the stable release channel*, and old unstable flags
10846 will warn about their usage. In the future, all unstable flags will
10847 be unavailable on the stable release channel.
10848* [It is no longer possible to `match` on empty enum variants using
10849 the `Variant(..)` syntax][1.8v]. This has been a warning since 1.6.
10850* The Unix-specific `MetadataExt` traits, including
10851 `os::unix::fs::MetadataExt`, which expose values such as inode
10852 numbers [no longer return platform-specific types][1.8r], but
10853 instead return widened integers. [RFC 1415].
10854* [Modules sourced from the filesystem cannot appear within arbitrary
10855 blocks, but only within other modules][1.8mf].
10856* [`--cfg` compiler flags are parsed strictly as identifiers][1.8c].
10857* On Unix, [stack overflow triggers a runtime abort instead of a
10858 SIGSEGV][1.8so].
10859* [`Command::spawn` and its equivalents return an error if any of
10860 its command-line arguments contain interior `NUL`s][1.8n].
10861* [Tuple and unit enum variants from other crates are in the type
10862 namespace][1.8tn].
10863* [On Windows `rustc` emits `.lib` files for the `staticlib` library
10864 type instead of `.a` files][1.8st]. Additionally, for the MSVC
10865 toolchain, `rustc` emits import libraries named `foo.dll.lib`
10866 instead of `foo.lib`.
10867
10868
10869[1.8a]: https://github.com/rust-lang/rust/pull/30962
10870[1.8b]: https://github.com/rust-lang/rust/pull/31123
10871[1.8c]: https://github.com/rust-lang/rust/pull/31530
10872[1.8cc]: https://github.com/rust-lang/cargo/pull/2397
10873[1.8ce]: https://github.com/rust-lang/cargo/pull/2398
10874[1.8cf]: https://github.com/rust-lang/rust/pull/31278
10875[1.8cfg]: https://github.com/rust-lang/cargo/pull/2328
10876[1.8ci]: https://github.com/rust-lang/cargo/pull/2081
10877[1.8ck]: https://github.com/rust-lang/cargo/pull/2370
10878[1.8ct]: https://github.com/rust-lang/cargo/pull/2335
10879[1.8cu]: https://github.com/rust-lang/rust/pull/31390
10880[1.8cfv]: https://github.com/rust-lang/cargo/issues/2365
10881[1.8cv]: https://github.com/rust-lang/rust/pull/30998
10882[1.8h]: https://github.com/rust-lang/rust/pull/31460
10883[1.8l]: https://github.com/rust-lang/rust/pull/31668
10884[1.8m]: https://github.com/rust-lang/rust/pull/31020
10885[1.8mf]: https://github.com/rust-lang/rust/pull/31534
10886[1.8mp]: https://github.com/rust-lang/rust/pull/30894
10887[1.8mr]: https://users.rust-lang.org/t/multirust-0-8-with-cross-std-installation/4901
10888[1.8ms]: https://github.com/rust-lang/rust/pull/30448
10889[1.8n]: https://github.com/rust-lang/rust/pull/31056
10890[1.8nx]: https://github.com/rust-lang/rust/pull/30859
10891[1.8r]: https://github.com/rust-lang/rust/pull/31551
10892[1.8so]: https://github.com/rust-lang/rust/pull/31333
10893[1.8st]: https://github.com/rust-lang/rust/pull/29520
10894[1.8t]: https://github.com/rust-lang/rust/pull/31358
10895[1.8tn]: https://github.com/rust-lang/rust/pull/30882
10896[1.8u]: https://github.com/rust-lang/rust/pull/31793
10897[1.8v]: https://github.com/rust-lang/rust/pull/31757
10898[1.8w]: https://github.com/rust-lang/rust/pull/31904
10899[RFC 1361]: https://github.com/rust-lang/rfcs/blob/master/text/1361-cargo-cfg-dependencies.md
10900[RFC 1415]: https://github.com/rust-lang/rfcs/blob/master/text/1415-trim-std-os.md
10901[RFC 218]: https://github.com/rust-lang/rfcs/blob/master/text/0218-empty-struct-with-braces.md
10902[RFC 953]: https://github.com/rust-lang/rfcs/blob/master/text/0953-op-assign.md
10903[`AddAssign`]: http://doc.rust-lang.org/nightly/std/ops/trait.AddAssign.html
10904[`BitAndAssign`]: http://doc.rust-lang.org/nightly/std/ops/trait.BitAndAssign.html
10905[`BitOrAssign`]: http://doc.rust-lang.org/nightly/std/ops/trait.BitOrAssign.html
10906[`BitXorAssign`]: http://doc.rust-lang.org/nightly/std/ops/trait.BitXorAssign.html
10907[`DivAssign`]: http://doc.rust-lang.org/nightly/std/ops/trait.DivAssign.html
10908[`Instant::duration_since`]: http://doc.rust-lang.org/nightly/std/time/struct.Instant.html#method.duration_since
10909[`Instant::elapsed`]: http://doc.rust-lang.org/nightly/std/time/struct.Instant.html#method.elapsed
10910[`Instant::now`]: http://doc.rust-lang.org/nightly/std/time/struct.Instant.html#method.now
10911[`MulAssign`]: http://doc.rust-lang.org/nightly/std/ops/trait.MulAssign.html
10912[`Ref::map`]: http://doc.rust-lang.org/nightly/std/cell/struct.Ref.html#method.map
10913[`RefMut::map`]: http://doc.rust-lang.org/nightly/std/cell/struct.RefMut.html#method.map
10914[`RemAssign`]: http://doc.rust-lang.org/nightly/std/ops/trait.RemAssign.html
10915[`ShlAssign`]: http://doc.rust-lang.org/nightly/std/ops/trait.ShlAssign.html
10916[`ShrAssign`]: http://doc.rust-lang.org/nightly/std/ops/trait.ShrAssign.html
10917[`SubAssign`]: http://doc.rust-lang.org/nightly/std/ops/trait.SubAssign.html
10918[`SystemTime::duration_since`]: http://doc.rust-lang.org/nightly/std/time/struct.SystemTime.html#method.duration_since
10919[`SystemTime::elapsed`]: http://doc.rust-lang.org/nightly/std/time/struct.SystemTime.html#method.elapsed
10920[`SystemTime::now`]: http://doc.rust-lang.org/nightly/std/time/struct.SystemTime.html#method.now
10921[`SystemTimeError::duration`]: http://doc.rust-lang.org/nightly/std/time/struct.SystemTimeError.html#method.duration
10922[`SystemTimeError`]: http://doc.rust-lang.org/nightly/std/time/struct.SystemTimeError.html
10923[`UNIX_EPOCH`]: http://doc.rust-lang.org/nightly/std/time/constant.UNIX_EPOCH.html
10924[`ptr::drop_in_place`]: http://doc.rust-lang.org/nightly/std/ptr/fn.drop_in_place.html
10925[`str::EncodeUtf16`]: http://doc.rust-lang.org/nightly/std/str/struct.EncodeUtf16.html
10926[`str::encode_utf16`]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.encode_utf16
10927[`time::Instant`]: http://doc.rust-lang.org/nightly/std/time/struct.Instant.html
10928[`time::SystemTime`]: http://doc.rust-lang.org/nightly/std/time/struct.SystemTime.html
10929
10930
10931Version 1.7.0 (2016-03-03)
10932==========================
10933
10934Libraries
10935---------
10936
10937* Stabilized APIs
10938 * `Path`
10939 * [`Path::strip_prefix`] (renamed from relative_from)
10940 * [`path::StripPrefixError`] (new error type returned from strip_prefix)
10941 * `Ipv4Addr`
10942 * [`Ipv4Addr::is_loopback`]
10943 * [`Ipv4Addr::is_private`]
10944 * [`Ipv4Addr::is_link_local`]
10945 * [`Ipv4Addr::is_multicast`]
10946 * [`Ipv4Addr::is_broadcast`]
10947 * [`Ipv4Addr::is_documentation`]
10948 * `Ipv6Addr`
10949 * [`Ipv6Addr::is_unspecified`]
10950 * [`Ipv6Addr::is_loopback`]
10951 * [`Ipv6Addr::is_multicast`]
10952 * `Vec`
10953 * [`Vec::as_slice`]
10954 * [`Vec::as_mut_slice`]
10955 * `String`
10956 * [`String::as_str`]
10957 * [`String::as_mut_str`]
10958 * Slices
10959 * `<[T]>::`[`clone_from_slice`], which now requires the two slices to
10960 be the same length
10961 * `<[T]>::`[`sort_by_key`]
10962 * checked, saturated, and overflowing operations
10963 * [`i32::checked_rem`], [`i32::checked_neg`], [`i32::checked_shl`], [`i32::checked_shr`]
10964 * [`i32::saturating_mul`]
10965 * [`i32::overflowing_add`], [`i32::overflowing_sub`], [`i32::overflowing_mul`], [`i32::overflowing_div`]
10966 * [`i32::overflowing_rem`], [`i32::overflowing_neg`], [`i32::overflowing_shl`], [`i32::overflowing_shr`]
10967 * [`u32::checked_rem`], [`u32::checked_neg`], [`u32::checked_shl`], [`u32::checked_shl`]
10968 * [`u32::saturating_mul`]
10969 * [`u32::overflowing_add`], [`u32::overflowing_sub`], [`u32::overflowing_mul`], [`u32::overflowing_div`]
10970 * [`u32::overflowing_rem`], [`u32::overflowing_neg`], [`u32::overflowing_shl`], [`u32::overflowing_shr`]
10971 * and checked, saturated, and overflowing operations for other primitive types
10972 * FFI
10973 * [`ffi::IntoStringError`]
10974 * [`CString::into_string`]
10975 * [`CString::into_bytes`]
10976 * [`CString::into_bytes_with_nul`]
10977 * `From<CString> for Vec<u8>`
10978 * `IntoStringError`
10979 * [`IntoStringError::into_cstring`]
10980 * [`IntoStringError::utf8_error`]
10981 * `Error for IntoStringError`
10982 * Hashing
10983 * [`std::hash::BuildHasher`]
10984 * [`BuildHasher::Hasher`]
10985 * [`BuildHasher::build_hasher`]
10986 * [`std::hash::BuildHasherDefault`]
10987 * [`HashMap::with_hasher`]
10988 * [`HashMap::with_capacity_and_hasher`]
10989 * [`HashSet::with_hasher`]
10990 * [`HashSet::with_capacity_and_hasher`]
10991 * [`std::collections::hash_map::RandomState`]
10992 * [`RandomState::new`]
10993* [Validating UTF-8 is faster by a factor of between 7 and 14x for
10994 ASCII input][1.7utf8]. This means that creating `String`s and `str`s
10995 from bytes is faster.
10996* [The performance of `LineWriter` (and thus `io::stdout`) was
10997 improved by using `memchr` to search for newlines][1.7m].
10998* [`f32::to_degrees` and `f32::to_radians` are stable][1.7f]. The
10999 `f64` variants were stabilized previously.
11000* [`BTreeMap` was rewritten to use less memory and improve the performance
11001 of insertion and iteration, the latter by as much as 5x][1.7bm].
11002* [`BTreeSet` and its iterators, `Iter`, `IntoIter`, and `Range` are
11003 covariant over their contained type][1.7bt].
11004* [`LinkedList` and its iterators, `Iter` and `IntoIter` are covariant
11005 over their contained type][1.7ll].
11006* [`str::replace` now accepts a `Pattern`][1.7rp], like other string
11007 searching methods.
11008* [`Any` is implemented for unsized types][1.7a].
11009* [`Hash` is implemented for `Duration`][1.7h].
11010
11011Misc
11012----
11013
11014* [When running tests with `--test`, rustdoc will pass `--cfg`
11015 arguments to the compiler][1.7dt].
11016* [The compiler is built with RPATH information by default][1.7rpa].
11017 This means that it will be possible to run `rustc` when installed in
11018 unusual configurations without configuring the dynamic linker search
11019 path explicitly.
11020* [`rustc` passes `--enable-new-dtags` to GNU ld][1.7dta]. This makes
11021 any RPATH entries (emitted with `-C rpath`) *not* take precedence
11022 over `LD_LIBRARY_PATH`.
11023
11024Cargo
11025-----
11026
11027* [`cargo rustc` accepts a `--profile` flag that runs `rustc` under
11028 any of the compilation profiles, 'dev', 'bench', or 'test'][1.7cp].
11029* [The `rerun-if-changed` build script directive no longer causes the
11030 build script to incorrectly run twice in certain scenarios][1.7rr].
11031
11032Compatibility Notes
11033-------------------
11034
11035* Soundness fixes to the interactions between associated types and
11036 lifetimes, specified in [RFC 1214], [now generate errors][1.7sf] for
11037 code that violates the new rules. This is a significant change that
11038 is known to break existing code, so it has emitted warnings for the
11039 new error cases since 1.4 to give crate authors time to adapt. The
11040 details of what is changing are subtle; read the RFC for more.
11041* [Several bugs in the compiler's visibility calculations were
11042 fixed][1.7v]. Since this was found to break significant amounts of
11043 code, the new errors will be emitted as warnings for several release
11044 cycles, under the `private_in_public` lint.
11045* Defaulted type parameters were accidentally accepted in positions
11046 that were not intended. In this release, [defaulted type parameters
11047 appearing outside of type definitions will generate a
11048 warning][1.7d], which will become an error in future releases.
11049* [Parsing "." as a float results in an error instead of 0][1.7p].
11050 That is, `".".parse::<f32>()` returns `Err`, not `Ok(0.0)`.
11051* [Borrows of closure parameters may not outlive the closure][1.7bc].
11052
11053[1.7a]: https://github.com/rust-lang/rust/pull/30928
11054[1.7bc]: https://github.com/rust-lang/rust/pull/30341
11055[1.7bm]: https://github.com/rust-lang/rust/pull/30426
11056[1.7bt]: https://github.com/rust-lang/rust/pull/30998
11057[1.7cp]: https://github.com/rust-lang/cargo/pull/2224
11058[1.7d]: https://github.com/rust-lang/rust/pull/30724
11059[1.7dt]: https://github.com/rust-lang/rust/pull/30372
11060[1.7dta]: https://github.com/rust-lang/rust/pull/30394
11061[1.7f]: https://github.com/rust-lang/rust/pull/30672
11062[1.7h]: https://github.com/rust-lang/rust/pull/30818
11063[1.7ll]: https://github.com/rust-lang/rust/pull/30663
11064[1.7m]: https://github.com/rust-lang/rust/pull/30381
11065[1.7p]: https://github.com/rust-lang/rust/pull/30681
11066[1.7rp]: https://github.com/rust-lang/rust/pull/29498
11067[1.7rpa]: https://github.com/rust-lang/rust/pull/30353
11068[1.7rr]: https://github.com/rust-lang/cargo/pull/2279
11069[1.7sf]: https://github.com/rust-lang/rust/pull/30389
11070[1.7utf8]: https://github.com/rust-lang/rust/pull/30740
11071[1.7v]: https://github.com/rust-lang/rust/pull/29973
11072[RFC 1214]: https://github.com/rust-lang/rfcs/blob/master/text/1214-projections-lifetimes-and-wf.md
11073[`BuildHasher::Hasher`]: http://doc.rust-lang.org/nightly/std/hash/trait.Hasher.html
11074[`BuildHasher::build_hasher`]: http://doc.rust-lang.org/nightly/std/hash/trait.BuildHasher.html#tymethod.build_hasher
11075[`CString::into_bytes_with_nul`]: http://doc.rust-lang.org/nightly/std/ffi/struct.CString.html#method.into_bytes_with_nul
11076[`CString::into_bytes`]: http://doc.rust-lang.org/nightly/std/ffi/struct.CString.html#method.into_bytes
11077[`CString::into_string`]: http://doc.rust-lang.org/nightly/std/ffi/struct.CString.html#method.into_string
11078[`HashMap::with_capacity_and_hasher`]: http://doc.rust-lang.org/nightly/std/collections/struct.HashMap.html#method.with_capacity_and_hasher
11079[`HashMap::with_hasher`]: http://doc.rust-lang.org/nightly/std/collections/struct.HashMap.html#method.with_hasher
11080[`HashSet::with_capacity_and_hasher`]: http://doc.rust-lang.org/nightly/std/collections/struct.HashSet.html#method.with_capacity_and_hasher
11081[`HashSet::with_hasher`]: http://doc.rust-lang.org/nightly/std/collections/struct.HashSet.html#method.with_hasher
11082[`IntoStringError::into_cstring`]: http://doc.rust-lang.org/nightly/std/ffi/struct.IntoStringError.html#method.into_cstring
11083[`IntoStringError::utf8_error`]: http://doc.rust-lang.org/nightly/std/ffi/struct.IntoStringError.html#method.utf8_error
11084[`Ipv4Addr::is_broadcast`]: http://doc.rust-lang.org/nightly/std/net/struct.Ipv4Addr.html#method.is_broadcast
11085[`Ipv4Addr::is_documentation`]: http://doc.rust-lang.org/nightly/std/net/struct.Ipv4Addr.html#method.is_documentation
11086[`Ipv4Addr::is_link_local`]: http://doc.rust-lang.org/nightly/std/net/struct.Ipv4Addr.html#method.is_link_local
11087[`Ipv4Addr::is_loopback`]: http://doc.rust-lang.org/nightly/std/net/struct.Ipv4Addr.html#method.is_loopback
11088[`Ipv4Addr::is_multicast`]: http://doc.rust-lang.org/nightly/std/net/struct.Ipv4Addr.html#method.is_multicast
11089[`Ipv4Addr::is_private`]: http://doc.rust-lang.org/nightly/std/net/struct.Ipv4Addr.html#method.is_private
11090[`Ipv6Addr::is_loopback`]: http://doc.rust-lang.org/nightly/std/net/struct.Ipv6Addr.html#method.is_loopback
11091[`Ipv6Addr::is_multicast`]: http://doc.rust-lang.org/nightly/std/net/struct.Ipv6Addr.html#method.is_multicast
11092[`Ipv6Addr::is_unspecified`]: http://doc.rust-lang.org/nightly/std/net/struct.Ipv6Addr.html#method.is_unspecified
11093[`Path::strip_prefix`]: http://doc.rust-lang.org/nightly/std/path/struct.Path.html#method.strip_prefix
11094[`RandomState::new`]: http://doc.rust-lang.org/nightly/std/collections/hash_map/struct.RandomState.html#method.new
11095[`String::as_mut_str`]: http://doc.rust-lang.org/nightly/std/string/struct.String.html#method.as_mut_str
11096[`String::as_str`]: http://doc.rust-lang.org/nightly/std/string/struct.String.html#method.as_str
11097[`Vec::as_mut_slice`]: http://doc.rust-lang.org/nightly/std/vec/struct.Vec.html#method.as_mut_slice
11098[`Vec::as_slice`]: http://doc.rust-lang.org/nightly/std/vec/struct.Vec.html#method.as_slice
11099[`clone_from_slice`]: http://doc.rust-lang.org/nightly/std/primitive.slice.html#method.clone_from_slice
11100[`ffi::IntoStringError`]: http://doc.rust-lang.org/nightly/std/ffi/struct.IntoStringError.html
11101[`i32::checked_neg`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.checked_neg
11102[`i32::checked_rem`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.checked_rem
11103[`i32::checked_shl`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.checked_shl
11104[`i32::checked_shr`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.checked_shr
11105[`i32::overflowing_add`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.overflowing_add
11106[`i32::overflowing_div`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.overflowing_div
11107[`i32::overflowing_mul`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.overflowing_mul
11108[`i32::overflowing_neg`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.overflowing_neg
11109[`i32::overflowing_rem`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.overflowing_rem
11110[`i32::overflowing_shl`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.overflowing_shl
11111[`i32::overflowing_shr`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.overflowing_shr
11112[`i32::overflowing_sub`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.overflowing_sub
11113[`i32::saturating_mul`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.saturating_mul
11114[`path::StripPrefixError`]: http://doc.rust-lang.org/nightly/std/path/struct.StripPrefixError.html
11115[`sort_by_key`]: http://doc.rust-lang.org/nightly/std/primitive.slice.html#method.sort_by_key
11116[`std::collections::hash_map::RandomState`]: http://doc.rust-lang.org/nightly/std/collections/hash_map/struct.RandomState.html
11117[`std::hash::BuildHasherDefault`]: http://doc.rust-lang.org/nightly/std/hash/struct.BuildHasherDefault.html
11118[`std::hash::BuildHasher`]: http://doc.rust-lang.org/nightly/std/hash/trait.BuildHasher.html
11119[`u32::checked_neg`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.checked_neg
11120[`u32::checked_rem`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.checked_rem
11121[`u32::checked_neg`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.checked_neg
11122[`u32::checked_shl`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.checked_shl
11123[`u32::overflowing_add`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.overflowing_add
11124[`u32::overflowing_div`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.overflowing_div
11125[`u32::overflowing_mul`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.overflowing_mul
11126[`u32::overflowing_neg`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.overflowing_neg
11127[`u32::overflowing_rem`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.overflowing_rem
11128[`u32::overflowing_shl`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.overflowing_shl
11129[`u32::overflowing_shr`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.overflowing_shr
11130[`u32::overflowing_sub`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.overflowing_sub
11131[`u32::saturating_mul`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.saturating_mul
11132
11133
11134Version 1.6.0 (2016-01-21)
11135==========================
11136
11137Language
11138--------
11139
11140* The `#![no_std]` attribute causes a crate to not be linked to the
11141 standard library, but only the [core library][1.6co], as described
11142 in [RFC 1184]. The core library defines common types and traits but
11143 has no platform dependencies whatsoever, and is the basis for Rust
11144 software in environments that cannot support a full port of the
11145 standard library, such as operating systems. Most of the core
11146 library is now stable.
11147
11148Libraries
11149---------
11150
11151* Stabilized APIs:
11152 [`Read::read_exact`],
11153 [`ErrorKind::UnexpectedEof`] (renamed from `UnexpectedEOF`),
11154 [`fs::DirBuilder`], [`fs::DirBuilder::new`],
11155 [`fs::DirBuilder::recursive`], [`fs::DirBuilder::create`],
11156 [`os::unix::fs::DirBuilderExt`],
11157 [`os::unix::fs::DirBuilderExt::mode`], [`vec::Drain`],
11158 [`vec::Vec::drain`], [`string::Drain`], [`string::String::drain`],
11159 [`vec_deque::Drain`], [`vec_deque::VecDeque::drain`],
11160 [`collections::hash_map::Drain`],
11161 [`collections::hash_map::HashMap::drain`],
11162 [`collections::hash_set::Drain`],
11163 [`collections::hash_set::HashSet::drain`],
11164 [`collections::binary_heap::Drain`],
11165 [`collections::binary_heap::BinaryHeap::drain`],
11166 [`Vec::extend_from_slice`] (renamed from `push_all`),
11167 [`Mutex::get_mut`], [`Mutex::into_inner`], [`RwLock::get_mut`],
11168 [`RwLock::into_inner`],
11169 [`Iterator::min_by_key`] (renamed from `min_by`),
11170 [`Iterator::max_by_key`] (renamed from `max_by`).
11171* The [core library][1.6co] is stable, as are most of its APIs.
11172* [The `assert_eq!` macro supports arguments that don't implement
11173 `Sized`][1.6ae], such as arrays. In this way it behaves more like
11174 `assert!`.
11175* Several timer functions that take duration in milliseconds [are
11176 deprecated in favor of those that take `Duration`][1.6ms]. These
11177 include `Condvar::wait_timeout_ms`, `thread::sleep_ms`, and
11178 `thread::park_timeout_ms`.
11179* The algorithm by which `Vec` reserves additional elements was
11180 [tweaked to not allocate excessive space][1.6a] while still growing
11181 exponentially.
11182* `From` conversions are [implemented from integers to floats][1.6f]
11183 in cases where the conversion is lossless. Thus they are not
11184 implemented for 32-bit ints to `f32`, nor for 64-bit ints to `f32`
11185 or `f64`. They are also not implemented for `isize` and `usize`
11186 because the implementations would be platform-specific. `From` is
11187 also implemented from `f32` to `f64`.
11188* `From<&Path>` and `From<PathBuf>` are implemented for `Cow<Path>`.
11189* `From<T>` is implemented for `Box<T>`, `Rc<T>` and `Arc<T>`.
11190* `IntoIterator` is implemented for `&PathBuf` and `&Path`.
11191* [`BinaryHeap` was refactored][1.6bh] for modest performance
11192 improvements.
11193* Sorting slices that are already sorted [is 50% faster in some
11194 cases][1.6s].
11195
11196Cargo
11197-----
11198
11199* Cargo will look in `$CARGO_HOME/bin` for subcommands [by default][1.6c].
11200* Cargo build scripts can specify their dependencies by emitting the
11201 [`rerun-if-changed`][1.6rr] key.
11202* crates.io will reject publication of crates with dependencies that
11203 have a wildcard version constraint. Crates with wildcard
11204 dependencies were seen to cause a variety of problems, as described
11205 in [RFC 1241]. Since 1.5 publication of such crates has emitted a
11206 warning.
11207* `cargo clean` [accepts a `--release` flag][1.6cc] to clean the
11208 release folder. A variety of artifacts that Cargo failed to clean
11209 are now correctly deleted.
11210
11211Misc
11212----
11213
11214* The `unreachable_code` lint [warns when a function call's argument
11215 diverges][1.6dv].
11216* The parser indicates [failures that may be caused by
11217 confusingly-similar Unicode characters][1.6uc]
11218* Certain macro errors [are reported at definition time][1.6m], not
11219 expansion.
11220
11221Compatibility Notes
11222-------------------
11223
11224* The compiler no longer makes use of the [`RUST_PATH`][1.6rp]
11225 environment variable when locating crates. This was a pre-cargo
11226 feature for integrating with the package manager that was
11227 accidentally never removed.
11228* [A number of bugs were fixed in the privacy checker][1.6p] that
11229 could cause previously-accepted code to break.
11230* [Modules and unit/tuple structs may not share the same name][1.6ts].
11231* [Bugs in pattern matching unit structs were fixed][1.6us]. The tuple
11232 struct pattern syntax (`Foo(..)`) can no longer be used to match
11233 unit structs. This is a warning now, but will become an error in
11234 future releases. Patterns that share the same name as a const are
11235 now an error.
11236* A bug was fixed that causes [rustc not to apply default type
11237 parameters][1.6xc] when resolving certain method implementations of
11238 traits defined in other crates.
11239
11240[1.6a]: https://github.com/rust-lang/rust/pull/29454
11241[1.6ae]: https://github.com/rust-lang/rust/pull/29770
11242[1.6bh]: https://github.com/rust-lang/rust/pull/29811
11243[1.6c]: https://github.com/rust-lang/cargo/pull/2192
11244[1.6cc]: https://github.com/rust-lang/cargo/pull/2131
11245[1.6co]: http://doc.rust-lang.org/core/index.html
11246[1.6dv]: https://github.com/rust-lang/rust/pull/30000
11247[1.6f]: https://github.com/rust-lang/rust/pull/29129
11248[1.6m]: https://github.com/rust-lang/rust/pull/29828
11249[1.6ms]: https://github.com/rust-lang/rust/pull/29604
11250[1.6p]: https://github.com/rust-lang/rust/pull/29726
11251[1.6rp]: https://github.com/rust-lang/rust/pull/30034
11252[1.6rr]: https://github.com/rust-lang/cargo/pull/2134
11253[1.6s]: https://github.com/rust-lang/rust/pull/29675
11254[1.6ts]: https://github.com/rust-lang/rust/issues/21546
11255[1.6uc]: https://github.com/rust-lang/rust/pull/29837
11256[1.6us]: https://github.com/rust-lang/rust/pull/29383
11257[1.6xc]: https://github.com/rust-lang/rust/issues/30123
11258[RFC 1184]: https://github.com/rust-lang/rfcs/blob/master/text/1184-stabilize-no_std.md
11259[RFC 1241]: https://github.com/rust-lang/rfcs/blob/master/text/1241-no-wildcard-deps.md
11260[`ErrorKind::UnexpectedEof`]: http://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html#variant.UnexpectedEof
11261[`Iterator::max_by_key`]: http://doc.rust-lang.org/nightly/std/iter/trait.Iterator.html#method.max_by_key
11262[`Iterator::min_by_key`]: http://doc.rust-lang.org/nightly/std/iter/trait.Iterator.html#method.min_by_key
11263[`Mutex::get_mut`]: http://doc.rust-lang.org/nightly/std/sync/struct.Mutex.html#method.get_mut
11264[`Mutex::into_inner`]: http://doc.rust-lang.org/nightly/std/sync/struct.Mutex.html#method.into_inner
11265[`Read::read_exact`]: http://doc.rust-lang.org/nightly/std/io/trait.Read.html#method.read_exact
11266[`RwLock::get_mut`]: http://doc.rust-lang.org/nightly/std/sync/struct.RwLock.html#method.get_mut
11267[`RwLock::into_inner`]: http://doc.rust-lang.org/nightly/std/sync/struct.RwLock.html#method.into_inner
11268[`Vec::extend_from_slice`]: http://doc.rust-lang.org/nightly/collections/vec/struct.Vec.html#method.extend_from_slice
11269[`collections::binary_heap::BinaryHeap::drain`]: http://doc.rust-lang.org/nightly/std/collections/binary_heap/struct.BinaryHeap.html#method.drain
11270[`collections::binary_heap::Drain`]: http://doc.rust-lang.org/nightly/std/collections/binary_heap/struct.Drain.html
11271[`collections::hash_map::Drain`]: http://doc.rust-lang.org/nightly/std/collections/hash_map/struct.Drain.html
11272[`collections::hash_map::HashMap::drain`]: http://doc.rust-lang.org/nightly/std/collections/hash_map/struct.HashMap.html#method.drain
11273[`collections::hash_set::Drain`]: http://doc.rust-lang.org/nightly/std/collections/hash_set/struct.Drain.html
11274[`collections::hash_set::HashSet::drain`]: http://doc.rust-lang.org/nightly/std/collections/hash_set/struct.HashSet.html#method.drain
11275[`fs::DirBuilder::create`]: http://doc.rust-lang.org/nightly/std/fs/struct.DirBuilder.html#method.create
11276[`fs::DirBuilder::new`]: http://doc.rust-lang.org/nightly/std/fs/struct.DirBuilder.html#method.new
11277[`fs::DirBuilder::recursive`]: http://doc.rust-lang.org/nightly/std/fs/struct.DirBuilder.html#method.recursive
11278[`fs::DirBuilder`]: http://doc.rust-lang.org/nightly/std/fs/struct.DirBuilder.html
11279[`os::unix::fs::DirBuilderExt::mode`]: http://doc.rust-lang.org/nightly/std/os/unix/fs/trait.DirBuilderExt.html#tymethod.mode
11280[`os::unix::fs::DirBuilderExt`]: http://doc.rust-lang.org/nightly/std/os/unix/fs/trait.DirBuilderExt.html
11281[`string::Drain`]: http://doc.rust-lang.org/nightly/std/string/struct.Drain.html
11282[`string::String::drain`]: http://doc.rust-lang.org/nightly/std/string/struct.String.html#method.drain
11283[`vec::Drain`]: http://doc.rust-lang.org/nightly/std/vec/struct.Drain.html
11284[`vec::Vec::drain`]: http://doc.rust-lang.org/nightly/std/vec/struct.Vec.html#method.drain
11285[`vec_deque::Drain`]: http://doc.rust-lang.org/nightly/std/collections/vec_deque/struct.Drain.html
11286[`vec_deque::VecDeque::drain`]: http://doc.rust-lang.org/nightly/std/collections/vec_deque/struct.VecDeque.html#method.drain
11287
11288
11289Version 1.5.0 (2015-12-10)
11290==========================
11291
11292* ~700 changes, numerous bugfixes
11293
11294Highlights
11295----------
11296
11297* Stabilized APIs:
11298 [`BinaryHeap::from`], [`BinaryHeap::into_sorted_vec`],
11299 [`BinaryHeap::into_vec`], [`Condvar::wait_timeout`],
11300 [`FileTypeExt::is_block_device`], [`FileTypeExt::is_char_device`],
11301 [`FileTypeExt::is_fifo`], [`FileTypeExt::is_socket`],
11302 [`FileTypeExt`], [`Formatter::alternate`], [`Formatter::fill`],
11303 [`Formatter::precision`], [`Formatter::sign_aware_zero_pad`],
11304 [`Formatter::sign_minus`], [`Formatter::sign_plus`],
11305 [`Formatter::width`], [`Iterator::cmp`], [`Iterator::eq`],
11306 [`Iterator::ge`], [`Iterator::gt`], [`Iterator::le`],
11307 [`Iterator::lt`], [`Iterator::ne`], [`Iterator::partial_cmp`],
11308 [`Path::canonicalize`], [`Path::exists`], [`Path::is_dir`],
11309 [`Path::is_file`], [`Path::metadata`], [`Path::read_dir`],
11310 [`Path::read_link`], [`Path::symlink_metadata`],
11311 [`Utf8Error::valid_up_to`], [`Vec::resize`],
11312 [`VecDeque::as_mut_slices`], [`VecDeque::as_slices`],
11313 [`VecDeque::insert`], [`VecDeque::shrink_to_fit`],
11314 [`VecDeque::swap_remove_back`], [`VecDeque::swap_remove_front`],
11315 [`slice::split_first_mut`], [`slice::split_first`],
11316 [`slice::split_last_mut`], [`slice::split_last`],
11317 [`char::from_u32_unchecked`], [`fs::canonicalize`],
11318 [`str::MatchIndices`], [`str::RMatchIndices`],
11319 [`str::match_indices`], [`str::rmatch_indices`],
11320 [`str::slice_mut_unchecked`], [`string::ParseError`].
11321* Rust applications hosted on crates.io can be installed locally to
11322 `~/.cargo/bin` with the [`cargo install`] command. Among other
11323 things this makes it easier to augment Cargo with new subcommands:
11324 when a binary named e.g. `cargo-foo` is found in `$PATH` it can be
11325 invoked as `cargo foo`.
11326* Crates with wildcard (`*`) dependencies will [emit warnings when
11327 published][1.5w]. In 1.6 it will no longer be possible to publish
11328 crates with wildcard dependencies.
11329
11330Breaking Changes
11331----------------
11332
11333* The rules determining when a particular lifetime must outlive
11334 a particular value (known as '[dropck]') have been [modified
11335 to not rely on parametricity][1.5p].
11336* [Implementations of `AsRef` and `AsMut` were added to `Box`, `Rc`,
11337 and `Arc`][1.5a]. Because these smart pointer types implement
11338 `Deref`, this causes breakage in cases where the interior type
11339 contains methods of the same name.
11340* [Correct a bug in Rc/Arc][1.5c] that caused [dropck] to be unaware
11341 that they could drop their content. Soundness fix.
11342* All method invocations are [properly checked][1.5wf1] for
11343 [well-formedness][1.5wf2]. Soundness fix.
11344* Traits whose supertraits contain `Self` are [not object
11345 safe][1.5o]. Soundness fix.
11346* Target specifications support a [`no_default_libraries`][1.5nd]
11347 setting that controls whether `-nodefaultlibs` is passed to the
11348 linker, and in turn the `is_like_windows` setting no longer affects
11349 the `-nodefaultlibs` flag.
11350* `#[derive(Show)]`, long-deprecated, [has been removed][1.5ds].
11351* The `#[inline]` and `#[repr]` attributes [can only appear
11352 in valid locations][1.5at].
11353* Native libraries linked from the local crate are [passed to
11354 the linker before native libraries from upstream crates][1.5nl].
11355* Two rarely-used attributes, `#[no_debug]` and
11356 `#[omit_gdb_pretty_printer_section]` [are feature gated][1.5fg].
11357* Negation of unsigned integers, which has been a warning for
11358 several releases, [is now behind a feature gate and will
11359 generate errors][1.5nu].
11360* The parser accidentally accepted visibility modifiers on
11361 enum variants, a bug [which has been fixed][1.5ev].
11362* [A bug was fixed that allowed `use` statements to import unstable
11363 features][1.5use].
11364
11365Language
11366--------
11367
11368* When evaluating expressions at compile-time that are not
11369 compile-time constants (const-evaluating expressions in non-const
11370 contexts), incorrect code such as overlong bitshifts and arithmetic
11371 overflow will [generate a warning instead of an error][1.5ce],
11372 delaying the error until runtime. This will allow the
11373 const-evaluator to be expanded in the future backwards-compatibly.
11374* The `improper_ctypes` lint [no longer warns about using `isize` and
11375 `usize` in FFI][1.5ict].
11376
11377Libraries
11378---------
11379
11380* `Arc<T>` and `Rc<T>` are [covariant with respect to `T` instead of
11381 invariant][1.5c].
11382* `Default` is [implemented for mutable slices][1.5d].
11383* `FromStr` is [implemented for `SockAddrV4` and `SockAddrV6`][1.5s].
11384* There are now `From` conversions [between floating point
11385 types][1.5f] where the conversions are lossless.
11386* There are now `From` conversions [between integer types][1.5i] where
11387 the conversions are lossless.
11388* [`fs::Metadata` implements `Clone`][1.5fs].
11389* The `parse` method [accepts a leading "+" when parsing
11390 integers][1.5pi].
11391* [`AsMut` is implemented for `Vec`][1.5am].
11392* The `clone_from` implementations for `String` and `BinaryHeap` [have
11393 been optimized][1.5cf] and no longer rely on the default impl.
11394* The `extern "Rust"`, `extern "C"`, `unsafe extern "Rust"` and
11395 `unsafe extern "C"` function types now [implement `Clone`,
11396 `PartialEq`, `Eq`, `PartialOrd`, `Ord`, `Hash`, `fmt::Pointer`, and
11397 `fmt::Debug` for up to 12 arguments][1.5fp].
11398* [Dropping `Vec`s is much faster in unoptimized builds when the
11399 element types don't implement `Drop`][1.5dv].
11400* A bug that caused in incorrect behavior when [combining `VecDeque`
11401 with zero-sized types][1.5vdz] was resolved.
11402* [`PartialOrd` for slices is faster][1.5po].
11403
11404Miscellaneous
11405-------------
11406
11407* [Crate metadata size was reduced by 20%][1.5md].
11408* [Improvements to code generation reduced the size of libcore by 3.3
11409 MB and rustc's memory usage by 18MB][1.5m].
11410* [Improvements to deref translation increased performance in
11411 unoptimized builds][1.5dr].
11412* Various errors in trait resolution [are deduplicated to only be
11413 reported once][1.5te].
11414* Rust has preliminary [support for rumprun kernels][1.5rr].
11415* Rust has preliminary [support for NetBSD on amd64][1.5na].
11416
11417[1.5use]: https://github.com/rust-lang/rust/pull/28364
11418[1.5po]: https://github.com/rust-lang/rust/pull/28436
11419[1.5ev]: https://github.com/rust-lang/rust/pull/28442
11420[1.5nu]: https://github.com/rust-lang/rust/pull/28468
11421[1.5dr]: https://github.com/rust-lang/rust/pull/28491
11422[1.5vdz]: https://github.com/rust-lang/rust/pull/28494
11423[1.5md]: https://github.com/rust-lang/rust/pull/28521
11424[1.5fg]: https://github.com/rust-lang/rust/pull/28522
11425[1.5dv]: https://github.com/rust-lang/rust/pull/28531
11426[1.5na]: https://github.com/rust-lang/rust/pull/28543
11427[1.5fp]: https://github.com/rust-lang/rust/pull/28560
11428[1.5rr]: https://github.com/rust-lang/rust/pull/28593
11429[1.5cf]: https://github.com/rust-lang/rust/pull/28602
11430[1.5nl]: https://github.com/rust-lang/rust/pull/28605
11431[1.5te]: https://github.com/rust-lang/rust/pull/28645
11432[1.5at]: https://github.com/rust-lang/rust/pull/28650
11433[1.5am]: https://github.com/rust-lang/rust/pull/28663
11434[1.5m]: https://github.com/rust-lang/rust/pull/28778
11435[1.5ict]: https://github.com/rust-lang/rust/pull/28779
11436[1.5a]: https://github.com/rust-lang/rust/pull/28811
11437[1.5pi]: https://github.com/rust-lang/rust/pull/28826
11438[1.5ce]: https://github.com/rust-lang/rfcs/blob/master/text/1229-compile-time-asserts.md
11439[1.5p]: https://github.com/rust-lang/rfcs/blob/master/text/1238-nonparametric-dropck.md
11440[1.5i]: https://github.com/rust-lang/rust/pull/28921
11441[1.5fs]: https://github.com/rust-lang/rust/pull/29021
11442[1.5f]: https://github.com/rust-lang/rust/pull/29129
11443[1.5ds]: https://github.com/rust-lang/rust/pull/29148
11444[1.5s]: https://github.com/rust-lang/rust/pull/29190
11445[1.5d]: https://github.com/rust-lang/rust/pull/29245
11446[1.5o]: https://github.com/rust-lang/rust/pull/29259
11447[1.5nd]: https://github.com/rust-lang/rust/pull/28578
11448[1.5wf2]: https://github.com/rust-lang/rfcs/blob/master/text/1214-projections-lifetimes-and-wf.md
11449[1.5wf1]: https://github.com/rust-lang/rust/pull/28669
11450[dropck]: https://doc.rust-lang.org/nightly/nomicon/dropck.html
11451[1.5c]: https://github.com/rust-lang/rust/pull/29110
11452[1.5w]: https://github.com/rust-lang/rfcs/blob/master/text/1241-no-wildcard-deps.md
11453[`cargo install`]: https://github.com/rust-lang/rfcs/blob/master/text/1200-cargo-install.md
11454[`BinaryHeap::from`]: http://doc.rust-lang.org/nightly/std/convert/trait.From.html#method.from
11455[`BinaryHeap::into_sorted_vec`]: http://doc.rust-lang.org/nightly/std/collections/struct.BinaryHeap.html#method.into_sorted_vec
11456[`BinaryHeap::into_vec`]: http://doc.rust-lang.org/nightly/std/collections/struct.BinaryHeap.html#method.into_vec
11457[`Condvar::wait_timeout`]: http://doc.rust-lang.org/nightly/std/sync/struct.Condvar.html#method.wait_timeout
11458[`FileTypeExt::is_block_device`]: http://doc.rust-lang.org/nightly/std/os/unix/fs/trait.FileTypeExt.html#tymethod.is_block_device
11459[`FileTypeExt::is_char_device`]: http://doc.rust-lang.org/nightly/std/os/unix/fs/trait.FileTypeExt.html#tymethod.is_char_device
11460[`FileTypeExt::is_fifo`]: http://doc.rust-lang.org/nightly/std/os/unix/fs/trait.FileTypeExt.html#tymethod.is_fifo
11461[`FileTypeExt::is_socket`]: http://doc.rust-lang.org/nightly/std/os/unix/fs/trait.FileTypeExt.html#tymethod.is_socket
11462[`FileTypeExt`]: http://doc.rust-lang.org/nightly/std/os/unix/fs/trait.FileTypeExt.html
11463[`Formatter::alternate`]: http://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html#method.alternate
11464[`Formatter::fill`]: http://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html#method.fill
11465[`Formatter::precision`]: http://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html#method.precision
11466[`Formatter::sign_aware_zero_pad`]: http://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html#method.sign_aware_zero_pad
11467[`Formatter::sign_minus`]: http://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html#method.sign_minus
11468[`Formatter::sign_plus`]: http://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html#method.sign_plus
11469[`Formatter::width`]: http://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html#method.width
11470[`Iterator::cmp`]: http://doc.rust-lang.org/nightly/core/iter/trait.Iterator.html#method.cmp
11471[`Iterator::eq`]: http://doc.rust-lang.org/nightly/core/iter/trait.Iterator.html#method.eq
11472[`Iterator::ge`]: http://doc.rust-lang.org/nightly/core/iter/trait.Iterator.html#method.ge
11473[`Iterator::gt`]: http://doc.rust-lang.org/nightly/core/iter/trait.Iterator.html#method.gt
11474[`Iterator::le`]: http://doc.rust-lang.org/nightly/core/iter/trait.Iterator.html#method.le
11475[`Iterator::lt`]: http://doc.rust-lang.org/nightly/core/iter/trait.Iterator.html#method.lt
11476[`Iterator::ne`]: http://doc.rust-lang.org/nightly/core/iter/trait.Iterator.html#method.ne
11477[`Iterator::partial_cmp`]: http://doc.rust-lang.org/nightly/core/iter/trait.Iterator.html#method.partial_cmp
11478[`Path::canonicalize`]: http://doc.rust-lang.org/nightly/std/path/struct.Path.html#method.canonicalize
11479[`Path::exists`]: http://doc.rust-lang.org/nightly/std/path/struct.Path.html#method.exists
11480[`Path::is_dir`]: http://doc.rust-lang.org/nightly/std/path/struct.Path.html#method.is_dir
11481[`Path::is_file`]: http://doc.rust-lang.org/nightly/std/path/struct.Path.html#method.is_file
11482[`Path::metadata`]: http://doc.rust-lang.org/nightly/std/path/struct.Path.html#method.metadata
11483[`Path::read_dir`]: http://doc.rust-lang.org/nightly/std/path/struct.Path.html#method.read_dir
11484[`Path::read_link`]: http://doc.rust-lang.org/nightly/std/path/struct.Path.html#method.read_link
11485[`Path::symlink_metadata`]: http://doc.rust-lang.org/nightly/std/path/struct.Path.html#method.symlink_metadata
11486[`Utf8Error::valid_up_to`]: http://doc.rust-lang.org/nightly/core/str/struct.Utf8Error.html#method.valid_up_to
11487[`Vec::resize`]: http://doc.rust-lang.org/nightly/std/vec/struct.Vec.html#method.resize
11488[`VecDeque::as_mut_slices`]: http://doc.rust-lang.org/nightly/std/collections/struct.VecDeque.html#method.as_mut_slices
11489[`VecDeque::as_slices`]: http://doc.rust-lang.org/nightly/std/collections/struct.VecDeque.html#method.as_slices
11490[`VecDeque::insert`]: http://doc.rust-lang.org/nightly/std/collections/struct.VecDeque.html#method.insert
11491[`VecDeque::shrink_to_fit`]: http://doc.rust-lang.org/nightly/std/collections/struct.VecDeque.html#method.shrink_to_fit
11492[`VecDeque::swap_remove_back`]: http://doc.rust-lang.org/nightly/std/collections/struct.VecDeque.html#method.swap_remove_back
11493[`VecDeque::swap_remove_front`]: http://doc.rust-lang.org/nightly/std/collections/struct.VecDeque.html#method.swap_remove_front
11494[`slice::split_first_mut`]: http://doc.rust-lang.org/nightly/std/primitive.slice.html#method.split_first_mut
11495[`slice::split_first`]: http://doc.rust-lang.org/nightly/std/primitive.slice.html#method.split_first
11496[`slice::split_last_mut`]: http://doc.rust-lang.org/nightly/std/primitive.slice.html#method.split_last_mut
11497[`slice::split_last`]: http://doc.rust-lang.org/nightly/std/primitive.slice.html#method.split_last
11498[`char::from_u32_unchecked`]: http://doc.rust-lang.org/nightly/std/char/fn.from_u32_unchecked.html
11499[`fs::canonicalize`]: http://doc.rust-lang.org/nightly/std/fs/fn.canonicalize.html
11500[`str::MatchIndices`]: http://doc.rust-lang.org/nightly/std/str/struct.MatchIndices.html
11501[`str::RMatchIndices`]: http://doc.rust-lang.org/nightly/std/str/struct.RMatchIndices.html
11502[`str::match_indices`]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.match_indices
11503[`str::rmatch_indices`]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.rmatch_indices
11504[`str::slice_mut_unchecked`]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.slice_mut_unchecked
11505[`string::ParseError`]: http://doc.rust-lang.org/nightly/std/string/enum.ParseError.html
11506
11507Version 1.4.0 (2015-10-29)
11508==========================
11509
11510* ~1200 changes, numerous bugfixes
11511
11512Highlights
11513----------
11514
11515* Windows builds targeting the 64-bit MSVC ABI and linker (instead of
11516 GNU) are now supported and recommended for use.
11517
11518Breaking Changes
11519----------------
11520
11521* [Several changes have been made to fix type soundness and improve
11522 the behavior of associated types][sound]. See [RFC 1214]. Although
11523 we have mostly introduced these changes as warnings this release, to
11524 become errors next release, there are still some scenarios that will
11525 see immediate breakage.
11526* [The `str::lines` and `BufRead::lines` iterators treat `\r\n` as
11527 line breaks in addition to `\n`][crlf].
11528* [Loans of `'static` lifetime extend to the end of a function][stat].
11529* [`str::parse` no longer introduces avoidable rounding error when
11530 parsing floating point numbers. Together with earlier changes to
11531 float formatting/output, "round trips" like f.to_string().parse()
11532 now preserve the value of f exactly. Additionally, leading plus
11533 signs are now accepted][fp3].
11534
11535
11536Language
11537--------
11538
11539* `use` statements that import multiple items [can now rename
11540 them][i], as in `use foo::{bar as kitten, baz as puppy}`.
11541* [Binops work correctly on fat pointers][binfat].
11542* `pub extern crate`, which does not behave as expected, [issues a
11543 warning][pec] until a better solution is found.
11544
11545Libraries
11546---------
11547
11548* [Many APIs were stabilized][stab]: `<Box<str>>::into_string`,
11549 [`Arc::downgrade`], [`Arc::get_mut`], [`Arc::make_mut`],
11550 [`Arc::try_unwrap`], [`Box::from_raw`], [`Box::into_raw`], [`CStr::to_str`],
11551 [`CStr::to_string_lossy`], [`CString::from_raw`], [`CString::into_raw`],
11552 [`IntoRawFd::into_raw_fd`], [`IntoRawFd`],
11553 `IntoRawHandle::into_raw_handle`, `IntoRawHandle`,
11554 `IntoRawSocket::into_raw_socket`, `IntoRawSocket`, [`Rc::downgrade`],
11555 [`Rc::get_mut`], [`Rc::make_mut`], [`Rc::try_unwrap`], [`Result::expect`],
11556 [`String::into_boxed_str`], [`TcpStream::read_timeout`],
11557 [`TcpStream::set_read_timeout`], [`TcpStream::set_write_timeout`],
11558 [`TcpStream::write_timeout`], [`UdpSocket::read_timeout`],
11559 [`UdpSocket::set_read_timeout`], [`UdpSocket::set_write_timeout`],
11560 [`UdpSocket::write_timeout`], `Vec::append`, `Vec::split_off`,
11561 [`VecDeque::append`], [`VecDeque::retain`], [`VecDeque::split_off`],
11562 [`rc::Weak::upgrade`], [`rc::Weak`], [`slice::Iter::as_slice`],
11563 [`slice::IterMut::into_slice`], [`str::CharIndices::as_str`],
11564 [`str::Chars::as_str`], [`str::split_at_mut`], [`str::split_at`],
11565 [`sync::Weak::upgrade`], [`sync::Weak`], [`thread::park_timeout`],
11566 [`thread::sleep`].
11567* [Some APIs were deprecated][dep]: `BTreeMap::with_b`,
11568 `BTreeSet::with_b`, `Option::as_mut_slice`, `Option::as_slice`,
11569 `Result::as_mut_slice`, `Result::as_slice`, `f32::from_str_radix`,
11570 `f64::from_str_radix`.
11571* [Reverse-searching strings is faster with the 'two-way'
11572 algorithm][s].
11573* [`std::io::copy` allows `?Sized` arguments][cc].
11574* The `Windows`, `Chunks`, and `ChunksMut` iterators over slices all
11575 [override `count`, `nth` and `last` with an *O*(1)
11576 implementation][it].
11577* [`Default` is implemented for arrays up to `[T; 32]`][d].
11578* [`IntoRawFd` has been added to the Unix-specific prelude,
11579 `IntoRawSocket` and `IntoRawHandle` to the Windows-specific
11580 prelude][pr].
11581* [`Extend<String>` and `FromIterator<String` are both implemented for
11582 `String`][es].
11583* [`IntoIterator` is implemented for references to `Option` and
11584 `Result`][into2].
11585* [`HashMap` and `HashSet` implement `Extend<&T>` where `T:
11586 Copy`][ext] as part of [RFC 839]. This will cause type inference
11587 breakage in rare situations.
11588* [`BinaryHeap` implements `Debug`][bh2].
11589* [`Borrow` and `BorrowMut` are implemented for fixed-size
11590 arrays][bm].
11591* [`extern fn`s with the "Rust" and "C" ABIs implement common
11592 traits including `Eq`, `Ord`, `Debug`, `Hash`][fp].
11593* [String comparison is faster][faststr].
11594* `&mut T` where `T: std::fmt::Write` [also implements
11595 `std::fmt::Write`][mutw].
11596* [A stable regression in `VecDeque::push_back` and other
11597 capacity-altering methods that caused panics for zero-sized types
11598 was fixed][vd].
11599* [Function pointers implement traits for up to 12 parameters][fp2].
11600
11601Miscellaneous
11602-------------
11603
11604* The compiler [no longer uses the 'morestack' feature to prevent
11605 stack overflow][mm]. Instead it uses guard pages and stack
11606 probes (though stack probes are not yet implemented on any platform
11607 but Windows).
11608* [The compiler matches traits faster when projections are involved][p].
11609* The 'improper_ctypes' lint [no longer warns about use of `isize` and
11610 `usize`][ffi].
11611* [Cargo now displays useful information about what its doing during
11612 `cargo update`][cu].
11613
11614[`Arc::downgrade`]: http://doc.rust-lang.org/nightly/alloc/arc/struct.Arc.html#method.downgrade
11615[`Arc::make_mut`]: http://doc.rust-lang.org/nightly/alloc/arc/struct.Arc.html#method.make_mut
11616[`Arc::get_mut`]: http://doc.rust-lang.org/nightly/alloc/arc/struct.Arc.html#method.get_mut
11617[`Arc::try_unwrap`]: http://doc.rust-lang.org/nightly/alloc/arc/struct.Arc.html#method.try_unwrap
11618[`Box::from_raw`]: http://doc.rust-lang.org/nightly/alloc/boxed/struct.Box.html#method.from_raw
11619[`Box::into_raw`]: http://doc.rust-lang.org/nightly/alloc/boxed/struct.Box.html#method.into_raw
11620[`CStr::to_str`]: http://doc.rust-lang.org/nightly/std/ffi/struct.CStr.html#method.to_str
11621[`CStr::to_string_lossy`]: http://doc.rust-lang.org/nightly/std/ffi/struct.CStr.html#method.to_string_lossy
11622[`CString::from_raw`]: http://doc.rust-lang.org/nightly/std/ffi/struct.CString.html#method.from_raw
11623[`CString::into_raw`]: http://doc.rust-lang.org/nightly/std/ffi/struct.CString.html#method.into_raw
11624[`IntoRawFd::into_raw_fd`]: http://doc.rust-lang.org/nightly/std/os/unix/io/trait.IntoRawFd.html#tymethod.into_raw_fd
11625[`IntoRawFd`]: http://doc.rust-lang.org/nightly/std/os/unix/io/trait.IntoRawFd.html
11626[`Rc::downgrade`]: http://doc.rust-lang.org/nightly/alloc/rc/struct.Rc.html#method.downgrade
11627[`Rc::get_mut`]: http://doc.rust-lang.org/nightly/alloc/rc/struct.Rc.html#method.get_mut
11628[`Rc::make_mut`]: http://doc.rust-lang.org/nightly/alloc/rc/struct.Rc.html#method.make_mut
11629[`Rc::try_unwrap`]: http://doc.rust-lang.org/nightly/alloc/rc/struct.Rc.html#method.try_unwrap
11630[`Result::expect`]: http://doc.rust-lang.org/nightly/core/result/enum.Result.html#method.expect
11631[`String::into_boxed_str`]: http://doc.rust-lang.org/nightly/collections/string/struct.String.html#method.into_boxed_str
11632[`TcpStream::read_timeout`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.read_timeout
11633[`TcpStream::set_read_timeout`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.set_read_timeout
11634[`TcpStream::write_timeout`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.write_timeout
11635[`TcpStream::set_write_timeout`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.set_write_timeout
11636[`UdpSocket::read_timeout`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.read_timeout
11637[`UdpSocket::set_read_timeout`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.set_read_timeout
11638[`UdpSocket::write_timeout`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.write_timeout
11639[`UdpSocket::set_write_timeout`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.set_write_timeout
11640[`VecDeque::append`]: http://doc.rust-lang.org/nightly/std/collections/struct.VecDeque.html#method.append
11641[`VecDeque::retain`]: http://doc.rust-lang.org/nightly/std/collections/struct.VecDeque.html#method.retain
11642[`VecDeque::split_off`]: http://doc.rust-lang.org/nightly/std/collections/struct.VecDeque.html#method.split_off
11643[`rc::Weak::upgrade`]: http://doc.rust-lang.org/nightly/std/rc/struct.Weak.html#method.upgrade
11644[`rc::Weak`]: http://doc.rust-lang.org/nightly/std/rc/struct.Weak.html
11645[`slice::Iter::as_slice`]: http://doc.rust-lang.org/nightly/std/slice/struct.Iter.html#method.as_slice
11646[`slice::IterMut::into_slice`]: http://doc.rust-lang.org/nightly/std/slice/struct.IterMut.html#method.into_slice
11647[`str::CharIndices::as_str`]: http://doc.rust-lang.org/nightly/std/str/struct.CharIndices.html#method.as_str
11648[`str::Chars::as_str`]: http://doc.rust-lang.org/nightly/std/str/struct.Chars.html#method.as_str
11649[`str::split_at_mut`]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.split_at_mut
11650[`str::split_at`]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.split_at
11651[`sync::Weak::upgrade`]: http://doc.rust-lang.org/nightly/std/sync/struct.Weak.html#method.upgrade
11652[`sync::Weak`]: http://doc.rust-lang.org/nightly/std/sync/struct.Weak.html
11653[`thread::park_timeout`]: http://doc.rust-lang.org/nightly/std/thread/fn.park_timeout.html
11654[`thread::sleep`]: http://doc.rust-lang.org/nightly/std/thread/fn.sleep.html
11655[bh2]: https://github.com/rust-lang/rust/pull/28156
11656[binfat]: https://github.com/rust-lang/rust/pull/28270
11657[bm]: https://github.com/rust-lang/rust/pull/28197
11658[cc]: https://github.com/rust-lang/rust/pull/27531
11659[crlf]: https://github.com/rust-lang/rust/pull/28034
11660[cu]: https://github.com/rust-lang/cargo/pull/1931
11661[d]: https://github.com/rust-lang/rust/pull/27825
11662[dep]: https://github.com/rust-lang/rust/pull/28339
11663[es]: https://github.com/rust-lang/rust/pull/27956
11664[ext]: https://github.com/rust-lang/rust/pull/28094
11665[faststr]: https://github.com/rust-lang/rust/pull/28338
11666[ffi]: https://github.com/rust-lang/rust/pull/28779
11667[fp]: https://github.com/rust-lang/rust/pull/28268
11668[fp2]: https://github.com/rust-lang/rust/pull/28560
11669[fp3]: https://github.com/rust-lang/rust/pull/27307
11670[i]: https://github.com/rust-lang/rust/pull/27451
11671[into2]: https://github.com/rust-lang/rust/pull/28039
11672[it]: https://github.com/rust-lang/rust/pull/27652
11673[mm]: https://github.com/rust-lang/rust/pull/27338
11674[mutw]: https://github.com/rust-lang/rust/pull/28368
11675[sound]: https://github.com/rust-lang/rust/pull/27641
11676[p]: https://github.com/rust-lang/rust/pull/27866
11677[pec]: https://github.com/rust-lang/rust/pull/28486
11678[pr]: https://github.com/rust-lang/rust/pull/27896
11679[RFC 839]: https://github.com/rust-lang/rfcs/blob/master/text/0839-embrace-extend-extinguish.md
11680[RFC 1214]: https://github.com/rust-lang/rfcs/blob/master/text/1214-projections-lifetimes-and-wf.md
11681[s]: https://github.com/rust-lang/rust/pull/27474
11682[stab]: https://github.com/rust-lang/rust/pull/28339
11683[stat]: https://github.com/rust-lang/rust/pull/28321
11684[vd]: https://github.com/rust-lang/rust/pull/28494
11685
11686Version 1.3.0 (2015-09-17)
11687==============================
11688
11689* ~900 changes, numerous bugfixes
11690
11691Highlights
11692----------
11693
11694* The [new object lifetime defaults][nold] have been [turned
11695 on][nold2] after a cycle of warnings about the change. Now types
11696 like `&'a Box<Trait>` (or `&'a Rc<Trait>`, etc) will change from
11697 being interpreted as `&'a Box<Trait+'a>` to `&'a
11698 Box<Trait+'static>`.
11699* [The Rustonomicon][nom] is a new book in the official documentation
11700 that dives into writing unsafe Rust.
11701* The [`Duration`] API, [has been stabilized][ds]. This basic unit of
11702 timekeeping is employed by other std APIs, as well as out-of-tree
11703 time crates.
11704
11705Breaking Changes
11706----------------
11707
11708* The [new object lifetime defaults][nold] have been [turned
11709 on][nold2] after a cycle of warnings about the change.
11710* There is a known [regression][lr] in how object lifetime elision is
11711 interpreted, the proper solution for which is undetermined.
11712* The `#[prelude_import]` attribute, an internal implementation
11713 detail, was accidentally stabilized previously. [It has been put
11714 behind the `prelude_import` feature gate][pi]. This change is
11715 believed to break no existing code.
11716* The behavior of [`size_of_val`][dst1] and [`align_of_val`][dst2] is
11717 [more sane for dynamically sized types][dst3]. Code that relied on
11718 the previous behavior is thought to be broken.
11719* The `dropck` rules, which checks that destructors can't access
11720 destroyed values, [have been updated][dropck] to match the
11721 [RFC][dropckrfc]. This fixes some soundness holes, and as such will
11722 cause some previously-compiling code to no longer build.
11723
11724Language
11725--------
11726
11727* The [new object lifetime defaults][nold] have been [turned
11728 on][nold2] after a cycle of warnings about the change.
11729* Semicolons may [now follow types and paths in
11730 macros](https://github.com/rust-lang/rust/pull/27000).
11731* The behavior of [`size_of_val`][dst1] and [`align_of_val`][dst2] is
11732 [more sane for dynamically sized types][dst3]. Code that relied on
11733 the previous behavior is not known to exist, and suspected to be
11734 broken.
11735* `'static` variables [may now be recursive][st].
11736* `ref` bindings choose between [`Deref`] and [`DerefMut`]
11737 implementations correctly.
11738* The `dropck` rules, which checks that destructors can't access
11739 destroyed values, [have been updated][dropck] to match the
11740 [RFC][dropckrfc].
11741
11742Libraries
11743---------
11744
11745* The [`Duration`] API, [has been stabilized][ds], as well as the
11746 `std::time` module, which presently contains only `Duration`.
11747* `Box<str>` and `Box<[T]>` both implement `Clone`.
11748* The owned C string, [`CString`], implements [`Borrow`] and the
11749 borrowed C string, [`CStr`], implements [`ToOwned`]. The two of
11750 these allow C strings to be borrowed and cloned in generic code.
11751* [`CStr`] implements [`Debug`].
11752* [`AtomicPtr`] implements [`Debug`].
11753* [`Error`] trait objects [can be downcast to their concrete types][e]
11754 in many common configurations, using the [`is`], [`downcast`],
11755 [`downcast_ref`] and [`downcast_mut`] methods, similarly to the
11756 [`Any`] trait.
11757* Searching for substrings now [employs the two-way algorithm][search]
11758 instead of doing a naive search. This gives major speedups to a
11759 number of methods, including [`contains`][sc], [`find`][sf],
11760 [`rfind`][srf], [`split`][ss]. [`starts_with`][ssw] and
11761 [`ends_with`][sew] are also faster.
11762* The performance of `PartialEq` for slices is [much faster][ps].
11763* The [`Hash`] trait offers the default method, [`hash_slice`], which
11764 is overridden and optimized by the implementations for scalars.
11765* The [`Hasher`] trait now has a number of specialized `write_*`
11766 methods for primitive types, for efficiency.
11767* The I/O-specific error type, [`std::io::Error`][ie], gained a set of
11768 methods for accessing the 'inner error', if any: [`get_ref`][iegr],
11769 [`get_mut`][iegm], [`into_inner`][ieii]. As well, the implementation
11770 of [`std::error::Error::cause`][iec] also delegates to the inner
11771 error.
11772* [`process::Child`][pc] gained the [`id`] method, which returns a
11773 `u32` representing the platform-specific process identifier.
11774* The [`connect`] method on slices is deprecated, replaced by the new
11775 [`join`] method (note that both of these are on the *unstable*
11776 [`SliceConcatExt`] trait, but through the magic of the prelude are
11777 available to stable code anyway).
11778* The [`Div`] operator is implemented for [`Wrapping`] types.
11779* [`DerefMut` is implemented for `String`][dms].
11780* Performance of SipHash (the default hasher for `HashMap`) is
11781 [better for long data][sh].
11782* [`AtomicPtr`] implements [`Send`].
11783* The [`read_to_end`] implementations for [`Stdin`] and [`File`]
11784 are now [specialized to use uninitialized buffers for increased
11785 performance][rte].
11786* Lifetime parameters of foreign functions [are now resolved
11787 properly][f].
11788
11789Misc
11790----
11791
11792* Rust can now, with some coercion, [produce programs that run on
11793 Windows XP][xp], though XP is not considered a supported platform.
11794* Porting Rust on Windows from the GNU toolchain to MSVC continues
11795 ([1][win1], [2][win2], [3][win3], [4][win4]). It is still not
11796 recommended for use in 1.3, though should be fully-functional
11797 in the [64-bit 1.4 beta][b14].
11798* On Fedora-based systems installation will [properly configure the
11799 dynamic linker][fl].
11800* The compiler gained many new extended error descriptions, which can
11801 be accessed with the `--explain` flag.
11802* The `dropck` pass, which checks that destructors can't access
11803 destroyed values, [has been rewritten][27261]. This fixes some
11804 soundness holes, and as such will cause some previously-compiling
11805 code to no longer build.
11806* `rustc` now uses [LLVM to write archive files where possible][ar].
11807 Eventually this will eliminate the compiler's dependency on the ar
11808 utility.
11809* Rust has [preliminary support for i686 FreeBSD][26959] (it has long
11810 supported FreeBSD on x86_64).
11811* The [`unused_mut`][lum], [`unconditional_recursion`][lur],
11812 [`improper_ctypes`][lic], and [`negate_unsigned`][lnu] lints are
11813 more strict.
11814* If landing pads are disabled (with `-Z no-landing-pads`), [`panic!`
11815 will kill the process instead of leaking][nlp].
11816
11817[`Any`]: http://doc.rust-lang.org/nightly/std/any/trait.Any.html
11818[`AtomicPtr`]: http://doc.rust-lang.org/nightly/std/sync/atomic/struct.AtomicPtr.html
11819[`Borrow`]: http://doc.rust-lang.org/nightly/std/borrow/trait.Borrow.html
11820[`CStr`]: http://doc.rust-lang.org/nightly/std/ffi/struct.CStr.html
11821[`CString`]: http://doc.rust-lang.org/nightly/std/ffi/struct.CString.html
11822[`Debug`]: http://doc.rust-lang.org/nightly/std/fmt/trait.Debug.html
11823[`DerefMut`]: http://doc.rust-lang.org/nightly/std/ops/trait.DerefMut.html
11824[`Deref`]: http://doc.rust-lang.org/nightly/std/ops/trait.Deref.html
11825[`Div`]: http://doc.rust-lang.org/nightly/std/ops/trait.Div.html
11826[`Duration`]: http://doc.rust-lang.org/nightly/std/time/struct.Duration.html
11827[`Error`]: http://doc.rust-lang.org/nightly/std/error/trait.Error.html
11828[`File`]: http://doc.rust-lang.org/nightly/std/fs/struct.File.html
11829[`Hash`]: http://doc.rust-lang.org/nightly/std/hash/trait.Hash.html
11830[`Hasher`]: http://doc.rust-lang.org/nightly/std/hash/trait.Hasher.html
11831[`Send`]: http://doc.rust-lang.org/nightly/std/marker/trait.Send.html
11832[`SliceConcatExt`]: http://doc.rust-lang.org/nightly/std/slice/trait.SliceConcatExt.html
11833[`Stdin`]: http://doc.rust-lang.org/nightly/std/io/struct.Stdin.html
11834[`ToOwned`]: http://doc.rust-lang.org/nightly/std/borrow/trait.ToOwned.html
11835[`Wrapping`]: http://doc.rust-lang.org/nightly/std/num/struct.Wrapping.html
11836[`connect`]: http://doc.rust-lang.org/nightly/std/slice/trait.SliceConcatExt.html#method.connect
11837[`downcast_mut`]: http://doc.rust-lang.org/nightly/std/error/trait.Error.html#method.downcast_mut
11838[`downcast_ref`]: http://doc.rust-lang.org/nightly/std/error/trait.Error.html#method.downcast_ref
11839[`downcast`]: http://doc.rust-lang.org/nightly/std/error/trait.Error.html#method.downcast
11840[`hash_slice`]: http://doc.rust-lang.org/nightly/std/hash/trait.Hash.html#method.hash_slice
11841[`id`]: http://doc.rust-lang.org/nightly/std/process/struct.Child.html#method.id
11842[`is`]: http://doc.rust-lang.org/nightly/std/error/trait.Error.html#method.is
11843[`join`]: http://doc.rust-lang.org/nightly/std/slice/trait.SliceConcatExt.html#method.join
11844[`read_to_end`]: http://doc.rust-lang.org/nightly/std/io/trait.Read.html#method.read_to_end
11845[ar]: https://github.com/rust-lang/rust/pull/26926
11846[b14]: https://static.rust-lang.org/dist/rust-beta-x86_64-pc-windows-msvc.msi
11847[dms]: https://github.com/rust-lang/rust/pull/26241
11848[27261]: https://github.com/rust-lang/rust/pull/27261
11849[dropckrfc]: https://github.com/rust-lang/rfcs/blob/master/text/0769-sound-generic-drop.md
11850[ds]: https://github.com/rust-lang/rust/pull/26818
11851[dst1]: http://doc.rust-lang.org/nightly/std/mem/fn.size_of_val.html
11852[dst2]: http://doc.rust-lang.org/nightly/std/mem/fn.align_of_val.html
11853[dst3]: https://github.com/rust-lang/rust/pull/27351
11854[e]: https://github.com/rust-lang/rust/pull/24793
11855[f]: https://github.com/rust-lang/rust/pull/26588
11856[26959]: https://github.com/rust-lang/rust/pull/26959
11857[fl]: https://github.com/rust-lang/rust-installer/pull/41
11858[ie]: http://doc.rust-lang.org/nightly/std/io/struct.Error.html
11859[iec]: http://doc.rust-lang.org/nightly/std/io/struct.Error.html#method.cause
11860[iegm]: http://doc.rust-lang.org/nightly/std/io/struct.Error.html#method.get_mut
11861[iegr]: http://doc.rust-lang.org/nightly/std/io/struct.Error.html#method.get_ref
11862[ieii]: http://doc.rust-lang.org/nightly/std/io/struct.Error.html#method.into_inner
11863[lic]: https://github.com/rust-lang/rust/pull/26583
11864[lnu]: https://github.com/rust-lang/rust/pull/27026
11865[lr]: https://github.com/rust-lang/rust/issues/27248
11866[lum]: https://github.com/rust-lang/rust/pull/26378
11867[lur]: https://github.com/rust-lang/rust/pull/26783
11868[nlp]: https://github.com/rust-lang/rust/pull/27176
11869[nold2]: https://github.com/rust-lang/rust/pull/27045
11870[nold]: https://github.com/rust-lang/rfcs/blob/master/text/1156-adjust-default-object-bounds.md
11871[nom]: http://doc.rust-lang.org/nightly/nomicon/
11872[pc]: http://doc.rust-lang.org/nightly/std/process/struct.Child.html
11873[pi]: https://github.com/rust-lang/rust/pull/26699
11874[ps]: https://github.com/rust-lang/rust/pull/26884
11875[rte]: https://github.com/rust-lang/rust/pull/26950
11876[sc]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.contains
11877[search]: https://github.com/rust-lang/rust/pull/26327
11878[sew]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.ends_with
11879[sf]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.find
11880[sh]: https://github.com/rust-lang/rust/pull/27280
11881[srf]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.rfind
11882[ss]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.split
11883[ssw]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.starts_with
11884[st]: https://github.com/rust-lang/rust/pull/26630
11885[win1]: https://github.com/rust-lang/rust/pull/26569
11886[win2]: https://github.com/rust-lang/rust/pull/26741
11887[win3]: https://github.com/rust-lang/rust/pull/26741
11888[win4]: https://github.com/rust-lang/rust/pull/27210
11889[xp]: https://github.com/rust-lang/rust/pull/26569
11890
11891Version 1.2.0 (2015-08-07)
11892==========================
11893
11894* ~1200 changes, numerous bugfixes
11895
11896Highlights
11897----------
11898
11899* [Dynamically-sized-type coercions][dst] allow smart pointer types
11900 like `Rc` to contain types without a fixed size, arrays and trait
11901 objects, finally enabling use of `Rc<[T]>` and completing the
11902 implementation of DST.
11903* [Parallel codegen][parcodegen] is now working again, which can
11904 substantially speed up large builds in debug mode; It also gets
11905 another ~33% speedup when bootstrapping on a 4 core machine (using 8
11906 jobs). It's not enabled by default, but will be "in the near
11907 future". It can be activated with the `-C codegen-units=N` flag to
11908 `rustc`.
11909* This is the first release with [experimental support for linking
11910 with the MSVC linker and lib C on Windows (instead of using the GNU
11911 variants via MinGW)][win]. It is yet recommended only for the most
11912 intrepid Rustaceans.
11913* Benchmark compilations are showing a 30% improvement in
11914 bootstrapping over 1.1.
11915
11916Breaking Changes
11917----------------
11918
11919* The [`to_uppercase`] and [`to_lowercase`] methods on `char` now do
11920 unicode case mapping, which is a previously-planned change in
11921 behavior and considered a bugfix.
11922* [`mem::align_of`] now specifies [the *minimum alignment* for
11923 T][align], which is usually the alignment programs are interested
11924 in, and the same value reported by clang's
11925 `alignof`. [`mem::min_align_of`] is deprecated. This is not known to
11926 break real code.
11927* [The `#[packed]` attribute is no longer silently accepted by the
11928 compiler][packed]. This attribute did nothing and code that
11929 mentioned it likely did not work as intended.
11930* Associated type defaults are [now behind the
11931 `associated_type_defaults` feature gate][ad]. In 1.1 associated type
11932 defaults *did not work*, but could be mentioned syntactically. As
11933 such this breakage has minimal impact.
11934
11935Language
11936--------
11937
11938* Patterns with `ref mut` now correctly invoke [`DerefMut`] when
11939 matching against dereferenceable values.
11940
11941Libraries
11942---------
11943
11944* The [`Extend`] trait, which grows a collection from an iterator, is
11945 implemented over iterators of references, for `String`, `Vec`,
11946 `LinkedList`, `VecDeque`, `EnumSet`, `BinaryHeap`, `VecMap`,
11947 `BTreeSet` and `BTreeMap`. [RFC][extend-rfc].
11948* The [`iter::once`] function returns an iterator that yields a single
11949 element, and [`iter::empty`] returns an iterator that yields no
11950 elements.
11951* The [`matches`] and [`rmatches`] methods on `str` return iterators
11952 over substring matches.
11953* [`Cell`] and [`RefCell`] both implement `Eq`.
11954* A number of methods for wrapping arithmetic are added to the
11955 integral types, [`wrapping_div`], [`wrapping_rem`],
11956 [`wrapping_neg`], [`wrapping_shl`], [`wrapping_shr`]. These are in
11957 addition to the existing [`wrapping_add`], [`wrapping_sub`], and
11958 [`wrapping_mul`] methods, and alternatives to the [`Wrapping`]
11959 type.. It is illegal for the default arithmetic operations in Rust
11960 to overflow; the desire to wrap must be explicit.
11961* The `{:#?}` formatting specifier [displays the alternate,
11962 pretty-printed][debugfmt] form of the `Debug` formatter. This
11963 feature was actually introduced prior to 1.0 with little
11964 fanfare.
11965* [`fmt::Formatter`] implements [`fmt::Write`], a `fmt`-specific trait
11966 for writing data to formatted strings, similar to [`io::Write`].
11967* [`fmt::Formatter`] adds 'debug builder' methods, [`debug_struct`],
11968 [`debug_tuple`], [`debug_list`], [`debug_set`], [`debug_map`]. These
11969 are used by code generators to emit implementations of [`Debug`].
11970* `str` has new [`to_uppercase`][strup] and [`to_lowercase`][strlow]
11971 methods that convert case, following Unicode case mapping.
11972* It is now easier to handle poisoned locks. The [`PoisonError`]
11973 type, returned by failing lock operations, exposes `into_inner`,
11974 `get_ref`, and `get_mut`, which all give access to the inner lock
11975 guard, and allow the poisoned lock to continue to operate. The
11976 `is_poisoned` method of [`RwLock`] and [`Mutex`] can poll for a
11977 poisoned lock without attempting to take the lock.
11978* On Unix the [`FromRawFd`] trait is implemented for [`Stdio`], and
11979 [`AsRawFd`] for [`ChildStdin`], [`ChildStdout`], [`ChildStderr`].
11980 On Windows the `FromRawHandle` trait is implemented for `Stdio`,
11981 and `AsRawHandle` for `ChildStdin`, `ChildStdout`,
11982 `ChildStderr`.
11983* [`io::ErrorKind`] has a new variant, `InvalidData`, which indicates
11984 malformed input.
11985
11986Misc
11987----
11988
11989* `rustc` employs smarter heuristics for guessing at [typos].
11990* `rustc` emits more efficient code for [no-op conversions between
11991 unsafe pointers][nop].
11992* Fat pointers are now [passed in pairs of immediate arguments][fat],
11993 resulting in faster compile times and smaller code.
11994
11995[`Extend`]: https://doc.rust-lang.org/nightly/std/iter/trait.Extend.html
11996[extend-rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0839-embrace-extend-extinguish.md
11997[`iter::once`]: https://doc.rust-lang.org/nightly/std/iter/fn.once.html
11998[`iter::empty`]: https://doc.rust-lang.org/nightly/std/iter/fn.empty.html
11999[`matches`]: https://doc.rust-lang.org/nightly/std/primitive.str.html#method.matches
12000[`rmatches`]: https://doc.rust-lang.org/nightly/std/primitive.str.html#method.rmatches
12001[`Cell`]: https://doc.rust-lang.org/nightly/std/cell/struct.Cell.html
12002[`RefCell`]: https://doc.rust-lang.org/nightly/std/cell/struct.RefCell.html
12003[`wrapping_add`]: https://doc.rust-lang.org/nightly/std/primitive.i8.html#method.wrapping_add
12004[`wrapping_sub`]: https://doc.rust-lang.org/nightly/std/primitive.i8.html#method.wrapping_sub
12005[`wrapping_mul`]: https://doc.rust-lang.org/nightly/std/primitive.i8.html#method.wrapping_mul
12006[`wrapping_div`]: https://doc.rust-lang.org/nightly/std/primitive.i8.html#method.wrapping_div
12007[`wrapping_rem`]: https://doc.rust-lang.org/nightly/std/primitive.i8.html#method.wrapping_rem
12008[`wrapping_neg`]: https://doc.rust-lang.org/nightly/std/primitive.i8.html#method.wrapping_neg
12009[`wrapping_shl`]: https://doc.rust-lang.org/nightly/std/primitive.i8.html#method.wrapping_shl
12010[`wrapping_shr`]: https://doc.rust-lang.org/nightly/std/primitive.i8.html#method.wrapping_shr
12011[`Wrapping`]: https://doc.rust-lang.org/nightly/std/num/struct.Wrapping.html
12012[`fmt::Formatter`]: https://doc.rust-lang.org/nightly/std/fmt/struct.Formatter.html
12013[`fmt::Write`]: https://doc.rust-lang.org/nightly/std/fmt/trait.Write.html
12014[`io::Write`]: https://doc.rust-lang.org/nightly/std/io/trait.Write.html
12015[`debug_struct`]: https://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html#method.debug_struct
12016[`debug_tuple`]: https://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html#method.debug_tuple
12017[`debug_list`]: https://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html#method.debug_list
12018[`debug_set`]: https://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html#method.debug_set
12019[`debug_map`]: https://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html#method.debug_map
12020[`Debug`]: https://doc.rust-lang.org/nightly/std/fmt/trait.Debug.html
12021[strup]: https://doc.rust-lang.org/nightly/std/primitive.str.html#method.to_uppercase
12022[strlow]: https://doc.rust-lang.org/nightly/std/primitive.str.html#method.to_lowercase
12023[`to_uppercase`]: https://doc.rust-lang.org/nightly/std/primitive.char.html#method.to_uppercase
12024[`to_lowercase`]: https://doc.rust-lang.org/nightly/std/primitive.char.html#method.to_lowercase
12025[`PoisonError`]: https://doc.rust-lang.org/nightly/std/sync/struct.PoisonError.html
12026[`RwLock`]: https://doc.rust-lang.org/nightly/std/sync/struct.RwLock.html
12027[`Mutex`]: https://doc.rust-lang.org/nightly/std/sync/struct.Mutex.html
12028[`FromRawFd`]: https://doc.rust-lang.org/nightly/std/os/unix/io/trait.FromRawFd.html
12029[`AsRawFd`]: https://doc.rust-lang.org/nightly/std/os/unix/io/trait.AsRawFd.html
12030[`Stdio`]: https://doc.rust-lang.org/nightly/std/process/struct.Stdio.html
12031[`ChildStdin`]: https://doc.rust-lang.org/nightly/std/process/struct.ChildStdin.html
12032[`ChildStdout`]: https://doc.rust-lang.org/nightly/std/process/struct.ChildStdout.html
12033[`ChildStderr`]: https://doc.rust-lang.org/nightly/std/process/struct.ChildStderr.html
12034[`io::ErrorKind`]: https://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html
12035[debugfmt]: https://www.reddit.com/r/rust/comments/3ceaui/psa_produces_prettyprinted_debug_output/
12036[`DerefMut`]: https://doc.rust-lang.org/nightly/std/ops/trait.DerefMut.html
12037[`mem::align_of`]: https://doc.rust-lang.org/nightly/std/mem/fn.align_of.html
12038[align]: https://github.com/rust-lang/rust/pull/25646
12039[`mem::min_align_of`]: https://doc.rust-lang.org/nightly/std/mem/fn.min_align_of.html
12040[typos]: https://github.com/rust-lang/rust/pull/26087
12041[nop]: https://github.com/rust-lang/rust/pull/26336
12042[fat]: https://github.com/rust-lang/rust/pull/26411
12043[dst]: https://github.com/rust-lang/rfcs/blob/master/text/0982-dst-coercion.md
12044[parcodegen]: https://github.com/rust-lang/rust/pull/26018
12045[packed]: https://github.com/rust-lang/rust/pull/25541
12046[ad]: https://github.com/rust-lang/rust/pull/27382
12047[win]: https://github.com/rust-lang/rust/pull/25350
12048
12049Version 1.1.0 (2015-06-25)
12050=========================
12051
12052* ~850 changes, numerous bugfixes
12053
12054Highlights
12055----------
12056
12057* The [`std::fs` module has been expanded][fs] to expand the set of
12058 functionality exposed:
12059 * `DirEntry` now supports optimizations like `file_type` and `metadata` which
12060 don't incur a syscall on some platforms.
12061 * A `symlink_metadata` function has been added.
12062 * The `fs::Metadata` structure now lowers to its OS counterpart, providing
12063 access to all underlying information.
12064* The compiler now contains extended explanations of many errors. When an error
12065 with an explanation occurs the compiler suggests using the `--explain` flag
12066 to read the explanation. Error explanations are also [available online][err-index].
12067* Thanks to multiple [improvements][sk] to [type checking][pre], as
12068 well as other work, the time to bootstrap the compiler decreased by
12069 32%.
12070
12071Libraries
12072---------
12073
12074* The [`str::split_whitespace`] method splits a string on unicode
12075 whitespace boundaries.
12076* On both Windows and Unix, new extension traits provide conversion of
12077 I/O types to and from the underlying system handles. On Unix, these
12078 traits are [`FromRawFd`] and [`AsRawFd`], on Windows `FromRawHandle`
12079 and `AsRawHandle`. These are implemented for `File`, `TcpStream`,
12080 `TcpListener`, and `UpdSocket`. Further implementations for
12081 `std::process` will be stabilized later.
12082* On Unix, [`std::os::unix::symlink`] creates symlinks. On
12083 Windows, symlinks can be created with
12084 `std::os::windows::symlink_dir` and
12085 `std::os::windows::symlink_file`.
12086* The `mpsc::Receiver` type can now be converted into an iterator with
12087 `into_iter` on the [`IntoIterator`] trait.
12088* `Ipv4Addr` can be created from `u32` with the `From<u32>`
12089 implementation of the [`From`] trait.
12090* The `Debug` implementation for `RangeFull` [creates output that is
12091 more consistent with other implementations][rf].
12092* [`Debug` is implemented for `File`][file].
12093* The `Default` implementation for `Arc` [no longer requires `Sync +
12094 Send`][arc].
12095* [The `Iterator` methods `count`, `nth`, and `last` have been
12096 overridden for slices to have *O*(1) performance instead of *O*(*n*)][si].
12097* Incorrect handling of paths on Windows has been improved in both the
12098 compiler and the standard library.
12099* [`AtomicPtr` gained a `Default` implementation][ap].
12100* In accordance with Rust's policy on arithmetic overflow `abs` now
12101 [panics on overflow when debug assertions are enabled][abs].
12102* The [`Cloned`] iterator, which was accidentally left unstable for
12103 1.0 [has been stabilized][c].
12104* The [`Incoming`] iterator, which iterates over incoming TCP
12105 connections, and which was accidentally unnamable in 1.0, [is now
12106 properly exported][inc].
12107* [`BinaryHeap`] no longer corrupts itself [when functions called by
12108 `sift_up` or `sift_down` panic][bh].
12109* The [`split_off`] method of `LinkedList` [no longer corrupts
12110 the list in certain scenarios][ll].
12111
12112Misc
12113----
12114
12115* Type checking performance [has improved notably][sk] with
12116 [multiple improvements][pre].
12117* The compiler [suggests code changes][ch] for more errors.
12118* rustc and it's build system have experimental support for [building
12119 toolchains against MUSL][m] instead of glibc on Linux.
12120* The compiler defines the `target_env` cfg value, which is used for
12121 distinguishing toolchains that are otherwise for the same
12122 platform. Presently this is set to `gnu` for common GNU Linux
12123 targets and for MinGW targets, and `musl` for MUSL Linux targets.
12124* The [`cargo rustc`][crc] command invokes a build with custom flags
12125 to rustc.
12126* [Android executables are always position independent][pie].
12127* [The `drop_with_repr_extern` lint warns about mixing `repr(C)`
12128 with `Drop`][24935].
12129
12130[`str::split_whitespace`]: https://doc.rust-lang.org/nightly/std/primitive.str.html#method.split_whitespace
12131[`FromRawFd`]: https://doc.rust-lang.org/nightly/std/os/unix/io/trait.FromRawFd.html
12132[`AsRawFd`]: https://doc.rust-lang.org/nightly/std/os/unix/io/trait.AsRawFd.html
12133[`std::os::unix::symlink`]: https://doc.rust-lang.org/nightly/std/os/unix/fs/fn.symlink.html
12134[`IntoIterator`]: https://doc.rust-lang.org/nightly/std/iter/trait.IntoIterator.html
12135[`From`]: https://doc.rust-lang.org/nightly/std/convert/trait.From.html
12136[rf]: https://github.com/rust-lang/rust/pull/24491
12137[err-index]: https://doc.rust-lang.org/error-index.html
12138[sk]: https://github.com/rust-lang/rust/pull/24615
12139[pre]: https://github.com/rust-lang/rust/pull/25323
12140[file]: https://github.com/rust-lang/rust/pull/24598
12141[ch]: https://github.com/rust-lang/rust/pull/24683
12142[arc]: https://github.com/rust-lang/rust/pull/24695
12143[si]: https://github.com/rust-lang/rust/pull/24701
12144[ap]: https://github.com/rust-lang/rust/pull/24834
12145[m]: https://github.com/rust-lang/rust/pull/24777
12146[fs]: https://github.com/rust-lang/rfcs/blob/master/text/1044-io-fs-2.1.md
12147[crc]: https://github.com/rust-lang/cargo/pull/1568
12148[pie]: https://github.com/rust-lang/rust/pull/24953
12149[abs]: https://github.com/rust-lang/rust/pull/25441
12150[c]: https://github.com/rust-lang/rust/pull/25496
12151[`Cloned`]: https://doc.rust-lang.org/nightly/std/iter/struct.Cloned.html
12152[`Incoming`]: https://doc.rust-lang.org/nightly/std/net/struct.Incoming.html
12153[inc]: https://github.com/rust-lang/rust/pull/25522
12154[bh]: https://github.com/rust-lang/rust/pull/25856
12155[`BinaryHeap`]: https://doc.rust-lang.org/nightly/std/collections/struct.BinaryHeap.html
12156[ll]: https://github.com/rust-lang/rust/pull/26022
12157[`split_off`]: https://doc.rust-lang.org/nightly/collections/linked_list/struct.LinkedList.html#method.split_off
12158[24935]: https://github.com/rust-lang/rust/pull/24935
12159
12160Version 1.0.0 (2015-05-15)
12161========================
12162
12163* ~1500 changes, numerous bugfixes
12164
12165Highlights
12166----------
12167
12168* The vast majority of the standard library is now `#[stable]`. It is
12169 no longer possible to use unstable features with a stable build of
12170 the compiler.
12171* Many popular crates on [crates.io] now work on the stable release
12172 channel.
12173* Arithmetic on basic integer types now [checks for overflow in debug
12174 builds][overflow].
12175
12176Language
12177--------
12178
12179* Several [restrictions have been added to trait coherence][coh] in
12180 order to make it easier for upstream authors to change traits
12181 without breaking downstream code.
12182* Digits of binary and octal literals are [lexed more eagerly][lex] to
12183 improve error messages and macro behavior. For example, `0b1234` is
12184 now lexed as `0b1234` instead of two tokens, `0b1` and `234`.
12185* Trait bounds [are always invariant][inv], eliminating the need for
12186 the `PhantomFn` and `MarkerTrait` lang items, which have been
12187 removed.
12188* ["-" is no longer a valid character in crate names][cr], the `extern crate
12189 "foo" as bar` syntax has been replaced with `extern crate foo as
12190 bar`, and Cargo now automatically translates "-" in *package* names
12191 to underscore for the crate name.
12192* [Lifetime shadowing is an error][lt].
12193* [`Send` no longer implies `'static`][send-rfc].
12194* [UFCS now supports trait-less associated paths][moar-ufcs] like
12195 `MyType::default()`.
12196* Primitive types [now have inherent methods][prim-inherent],
12197 obviating the need for extension traits like `SliceExt`.
12198* Methods with `Self: Sized` in their `where` clause are [considered
12199 object-safe][self-sized], allowing many extension traits like
12200 `IteratorExt` to be merged into the traits they extended.
12201* You can now [refer to associated types][assoc-where] whose
12202 corresponding trait bounds appear only in a `where` clause.
12203* The final bits of [OIBIT landed][oibit-final], meaning that traits
12204 like `Send` and `Sync` are now library-defined.
12205* A [Reflect trait][reflect] was introduced, which means that
12206 downcasting via the `Any` trait is effectively limited to concrete
12207 types. This helps retain the potentially-important "parametricity"
12208 property: generic code cannot behave differently for different type
12209 arguments except in minor ways.
12210* The `unsafe_destructor` feature is now deprecated in favor of the
12211 [new `dropck`][rfc769]. This change is a major reduction in unsafe
12212 code.
12213
12214Libraries
12215---------
12216
12217* The `thread_local` module [has been renamed to `std::thread`][th].
12218* The methods of `IteratorExt` [have been moved to the `Iterator`
12219 trait itself][23300].
12220* Several traits that implement Rust's conventions for type
12221 conversions, `AsMut`, `AsRef`, `From`, and `Into` have been
12222 [centralized in the `std::convert` module][con].
12223* The `FromError` trait [was removed in favor of `From`][fe].
12224* The basic sleep function [has moved to
12225 `std::thread::sleep_ms`][slp].
12226* The `splitn` function now takes an `n` parameter that represents the
12227 number of items yielded by the returned iterator [instead of the
12228 number of 'splits'][spl].
12229* [On Unix, all file descriptors are `CLOEXEC` by default][clo].
12230* [Derived implementations of `PartialOrd` now order enums according
12231 to their explicitly-assigned discriminants][po].
12232* [Methods for searching strings are generic over `Pattern`s][pat],
12233 implemented presently by `&char`, `&str`, `FnMut(char) -> bool` and
12234 some others.
12235* [In method resolution, object methods are resolved before inherent
12236 methods][meth].
12237* [`String::from_str` has been deprecated in favor of the `From` impl,
12238 `String::from`][24517].
12239* [`io::Error` implements `Sync`][ios].
12240* [The `words` method on `&str` has been replaced with
12241 `split_whitespace`][sw], to avoid answering the tricky question, 'what is
12242 a word?'
12243* The new path and IO modules are complete and `#[stable]`. This
12244 was the major library focus for this cycle.
12245* The path API was [revised][path-normalize] to normalize `.`,
12246 adjusting the tradeoffs in favor of the most common usage.
12247* A large number of remaining APIs in `std` were also stabilized
12248 during this cycle; about 75% of the non-deprecated API surface
12249 is now stable.
12250* The new [string pattern API][string-pattern] landed, which makes
12251 the string slice API much more internally consistent and flexible.
12252* A new set of [generic conversion traits][conversion] replaced
12253 many existing ad hoc traits.
12254* Generic numeric traits were [completely removed][num-traits]. This
12255 was made possible thanks to inherent methods for primitive types,
12256 and the removal gives maximal flexibility for designing a numeric
12257 hierarchy in the future.
12258* The `Fn` traits are now related via [inheritance][fn-inherit]
12259 and provide ergonomic [blanket implementations][fn-blanket].
12260* The `Index` and `IndexMut` traits were changed to
12261 [take the index by value][index-value], enabling code like
12262 `hash_map["string"]` to work.
12263* `Copy` now [inherits][copy-clone] from `Clone`, meaning that all
12264 `Copy` data is known to be `Clone` as well.
12265
12266Misc
12267----
12268
12269* Many errors now have extended explanations that can be accessed with
12270 the `--explain` flag to `rustc`.
12271* Many new examples have been added to the standard library
12272 documentation.
12273* rustdoc has received a number of improvements focused on completion
12274 and polish.
12275* Metadata was tuned, shrinking binaries [by 27%][metadata-shrink].
12276* Much headway was made on ecosystem-wide CI, making it possible
12277 to [compare builds for breakage][ci-compare].
12278
12279
12280[crates.io]: http://crates.io
12281[clo]: https://github.com/rust-lang/rust/pull/24034
12282[coh]: https://github.com/rust-lang/rfcs/blob/master/text/1023-rebalancing-coherence.md
12283[con]: https://github.com/rust-lang/rust/pull/23875
12284[cr]: https://github.com/rust-lang/rust/pull/23419
12285[fe]: https://github.com/rust-lang/rust/pull/23879
12286[23300]: https://github.com/rust-lang/rust/pull/23300
12287[inv]: https://github.com/rust-lang/rust/pull/23938
12288[ios]: https://github.com/rust-lang/rust/pull/24133
12289[lex]: https://github.com/rust-lang/rfcs/blob/master/text/0879-small-base-lexing.md
12290[lt]: https://github.com/rust-lang/rust/pull/24057
12291[meth]: https://github.com/rust-lang/rust/pull/24056
12292[pat]: https://github.com/rust-lang/rfcs/blob/master/text/0528-string-patterns.md
12293[po]: https://github.com/rust-lang/rust/pull/24270
12294[24517]: https://github.com/rust-lang/rust/pull/24517
12295[slp]: https://github.com/rust-lang/rust/pull/23949
12296[spl]: https://github.com/rust-lang/rfcs/blob/master/text/0979-align-splitn-with-other-languages.md
12297[sw]: https://github.com/rust-lang/rfcs/blob/master/text/1054-str-words.md
12298[th]: https://github.com/rust-lang/rfcs/blob/master/text/0909-move-thread-local-to-std-thread.md
12299[send-rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0458-send-improvements.md
12300[moar-ufcs]: https://github.com/rust-lang/rust/pull/22172
12301[prim-inherent]: https://github.com/rust-lang/rust/pull/23104
12302[overflow]: https://github.com/rust-lang/rfcs/blob/master/text/0560-integer-overflow.md
12303[metadata-shrink]: https://github.com/rust-lang/rust/pull/22971
12304[self-sized]: https://github.com/rust-lang/rust/pull/22301
12305[assoc-where]: https://github.com/rust-lang/rust/pull/22512
12306[string-pattern]: https://github.com/rust-lang/rust/pull/22466
12307[oibit-final]: https://github.com/rust-lang/rust/pull/21689
12308[reflect]: https://github.com/rust-lang/rust/pull/23712
12309[conversion]: https://github.com/rust-lang/rfcs/pull/529
12310[num-traits]: https://github.com/rust-lang/rust/pull/23549
12311[index-value]: https://github.com/rust-lang/rust/pull/23601
12312[rfc769]: https://github.com/rust-lang/rfcs/pull/769
12313[ci-compare]: https://gist.github.com/brson/a30a77836fbec057cbee
12314[fn-inherit]: https://github.com/rust-lang/rust/pull/23282
12315[fn-blanket]: https://github.com/rust-lang/rust/pull/23895
12316[copy-clone]: https://github.com/rust-lang/rust/pull/23860
12317[path-normalize]: https://github.com/rust-lang/rust/pull/23229
12318
12319
12320Version 1.0.0-alpha.2 (2015-02-20)
12321=====================================
12322
12323* ~1300 changes, numerous bugfixes
12324
12325* Highlights
12326
12327 * The various I/O modules were [overhauled][io-rfc] to reduce
12328 unnecessary abstractions and provide better interoperation with
12329 the underlying platform. The old `io` module remains temporarily
12330 at `std::old_io`.
12331 * The standard library now [participates in feature gating][feat],
12332 so use of unstable libraries now requires a `#![feature(...)]`
12333 attribute. The impact of this change is [described on the
12334 forum][feat-forum]. [RFC][feat-rfc].
12335
12336* Language
12337
12338 * `for` loops [now operate on the `IntoIterator` trait][into],
12339 which eliminates the need to call `.iter()`, etc. to iterate
12340 over collections. There are some new subtleties to remember
12341 though regarding what sort of iterators various types yield, in
12342 particular that `for foo in bar { }` yields values from a move
12343 iterator, destroying the original collection. [RFC][into-rfc].
12344 * Objects now have [default lifetime bounds][obj], so you don't
12345 have to write `Box<Trait+'static>` when you don't care about
12346 storing references. [RFC][obj-rfc].
12347 * In types that implement `Drop`, [lifetimes must outlive the
12348 value][drop]. This will soon make it possible to safely
12349 implement `Drop` for types where `#[unsafe_destructor]` is now
12350 required. Read the [gorgeous RFC][drop-rfc] for details.
12351 * The fully qualified <T as Trait>::X syntax lets you set the Self
12352 type for a trait method or associated type. [RFC][ufcs-rfc].
12353 * References to types that implement `Deref<U>` now [automatically
12354 coerce to references][deref] to the dereferenced type `U`,
12355 e.g. `&T where T: Deref<U>` automatically coerces to `&U`. This
12356 should eliminate many unsightly uses of `&*`, as when converting
12357 from references to vectors into references to
12358 slices. [RFC][deref-rfc].
12359 * The explicit [closure kind syntax][close] (`|&:|`, `|&mut:|`,
12360 `|:|`) is obsolete and closure kind is inferred from context.
12361 * [`Self` is a keyword][Self].
12362
12363* Libraries
12364
12365 * The `Show` and `String` formatting traits [have been
12366 renamed][fmt] to `Debug` and `Display` to more clearly reflect
12367 their related purposes. Automatically getting a string
12368 conversion to use with `format!("{:?}", something_to_debug)` is
12369 now written `#[derive(Debug)]`.
12370 * Abstract [OS-specific string types][osstr], `std::ff::{OsString,
12371 OsStr}`, provide strings in platform-specific encodings for easier
12372 interop with system APIs. [RFC][osstr-rfc].
12373 * The `boxed::into_raw` and `Box::from_raw` functions [convert
12374 between `Box<T>` and `*mut T`][boxraw], a common pattern for
12375 creating raw pointers.
12376
12377* Tooling
12378
12379 * Certain long error messages of the form 'expected foo found bar'
12380 are now [split neatly across multiple
12381 lines][multiline]. Examples in the PR.
12382 * On Unix Rust can be [uninstalled][un] by running
12383 `/usr/local/lib/rustlib/uninstall.sh`.
12384 * The `#[rustc_on_unimplemented]` attribute, requiring the
12385 'on_unimplemented' feature, lets rustc [display custom error
12386 messages when a trait is expected to be implemented for a type
12387 but is not][onun].
12388
12389* Misc
12390
12391 * Rust is tested against a [LALR grammar][lalr], which parses
12392 almost all the Rust files that rustc does.
12393
12394[boxraw]: https://github.com/rust-lang/rust/pull/21318
12395[close]: https://github.com/rust-lang/rust/pull/21843
12396[deref]: https://github.com/rust-lang/rust/pull/21351
12397[deref-rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0241-deref-conversions.md
12398[drop]: https://github.com/rust-lang/rust/pull/21972
12399[drop-rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0769-sound-generic-drop.md
12400[feat]: https://github.com/rust-lang/rust/pull/21248
12401[feat-forum]: https://users.rust-lang.org/t/psa-important-info-about-rustcs-new-feature-staging/82/5
12402[feat-rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0507-release-channels.md
12403[fmt]: https://github.com/rust-lang/rust/pull/21457
12404[into]: https://github.com/rust-lang/rust/pull/20790
12405[into-rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0235-collections-conventions.md#intoiterator-and-iterable
12406[io-rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0517-io-os-reform.md
12407[lalr]: https://github.com/rust-lang/rust/pull/21452
12408[multiline]: https://github.com/rust-lang/rust/pull/19870
12409[obj]: https://github.com/rust-lang/rust/pull/22230
12410[obj-rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0599-default-object-bound.md
12411[onun]: https://github.com/rust-lang/rust/pull/20889
12412[osstr]: https://github.com/rust-lang/rust/pull/21488
12413[osstr-rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0517-io-os-reform.md
12414[Self]: https://github.com/rust-lang/rust/pull/22158
12415[ufcs-rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0132-ufcs.md
12416[un]: https://github.com/rust-lang/rust/pull/22256
12417
12418
12419Version 1.0.0-alpha (2015-01-09)
12420==================================
12421
12422 * ~2400 changes, numerous bugfixes
12423
12424 * Highlights
12425
12426 * The language itself is considered feature complete for 1.0,
12427 though there will be many usability improvements and bugfixes
12428 before the final release.
12429 * Nearly 50% of the public API surface of the standard library has
12430 been declared 'stable'. Those interfaces are unlikely to change
12431 before 1.0.
12432 * The long-running debate over integer types has been
12433 [settled][ints]: Rust will ship with types named `isize` and
12434 `usize`, rather than `int` and `uint`, for pointer-sized
12435 integers. Guidelines will be rolled out during the alpha cycle.
12436 * Most crates that are not `std` have been moved out of the Rust
12437 distribution into the Cargo ecosystem so they can evolve
12438 separately and don't need to be stabilized as quickly, including
12439 'time', 'getopts', 'num', 'regex', and 'term'.
12440 * Documentation continues to be expanded with more API coverage, more
12441 examples, and more in-depth explanations. The guides have been
12442 consolidated into [The Rust Programming Language][trpl].
12443 * "[Rust By Example][rbe]" is now maintained by the Rust team.
12444 * All official Rust binary installers now come with [Cargo], the
12445 Rust package manager.
12446
12447* Language
12448
12449 * Closures have been [completely redesigned][unboxed] to be
12450 implemented in terms of traits, can now be used as generic type
12451 bounds and thus monomorphized and inlined, or via an opaque
12452 pointer (boxed) as in the old system. The new system is often
12453 referred to as 'unboxed' closures.
12454 * Traits now support [associated types][assoc], allowing families
12455 of related types to be defined together and used generically in
12456 powerful ways.
12457 * Enum variants are [namespaced by their type names][enum].
12458 * [`where` clauses][where] provide a more versatile and attractive
12459 syntax for specifying generic bounds, though the previous syntax
12460 remains valid.
12461 * Rust again picks a [fallback][fb] (either i32 or f64) for uninferred
12462 numeric types.
12463 * Rust [no longer has a runtime][rt] of any description, and only
12464 supports OS threads, not green threads.
12465 * At long last, Rust has been overhauled for 'dynamically-sized
12466 types' ([DST]), which integrates 'fat pointers' (object types,
12467 arrays, and `str`) more deeply into the type system, making it
12468 more consistent.
12469 * Rust now has a general [range syntax][range], `i..j`, `i..`, and
12470 `..j` that produce range types and which, when combined with the
12471 `Index` operator and multidispatch, leads to a convenient slice
12472 notation, `[i..j]`.
12473 * The new range syntax revealed an ambiguity in the fixed-length
12474 array syntax, so now fixed length arrays [are written `[T;
12475 N]`][arrays].
12476 * The `Copy` trait is no longer implemented automatically. Unsafe
12477 pointers no longer implement `Sync` and `Send` so types
12478 containing them don't automatically either. `Sync` and `Send`
12479 are now 'unsafe traits' so one can "forcibly" implement them via
12480 `unsafe impl` if a type confirms to the requirements for them
12481 even though the internals do not (e.g. structs containing unsafe
12482 pointers like `Arc`). These changes are intended to prevent some
12483 footguns and are collectively known as [opt-in built-in
12484 traits][oibit] (though `Sync` and `Send` will soon become pure
12485 library types unknown to the compiler).
12486 * Operator traits now take their operands [by value][ops], and
12487 comparison traits can use multidispatch to compare one type
12488 against multiple other types, allowing e.g. `String` to be
12489 compared with `&str`.
12490 * `if let` and `while let` are no longer feature-gated.
12491 * Rust has adopted a more [uniform syntax for escaping unicode
12492 characters][unicode].
12493 * `macro_rules!` [has been declared stable][mac]. Though it is a
12494 flawed system it is sufficiently popular that it must be usable
12495 for 1.0. Effort has gone into [future-proofing][mac-future] it
12496 in ways that will allow other macro systems to be developed in
12497 parallel, and won't otherwise impact the evolution of the
12498 language.
12499 * The prelude has been [pared back significantly][prelude] such
12500 that it is the minimum necessary to support the most pervasive
12501 code patterns, and through [generalized where clauses][where]
12502 many of the prelude extension traits have been consolidated.
12503 * Rust's rudimentary reflection [has been removed][refl], as it
12504 incurred too much code generation for little benefit.
12505 * [Struct variants][structvars] are no longer feature-gated.
12506 * Trait bounds can be [polymorphic over lifetimes][hrtb]. Also
12507 known as 'higher-ranked trait bounds', this crucially allows
12508 unboxed closures to work.
12509 * Macros invocations surrounded by parens or square brackets and
12510 not terminated by a semicolon are [parsed as
12511 expressions][macros], which makes expressions like `vec![1i32,
12512 2, 3].len()` work as expected.
12513 * Trait objects now implement their traits automatically, and
12514 traits that can be coerced to objects now must be [object
12515 safe][objsafe].
12516 * Automatically deriving traits is now done with `#[derive(...)]`
12517 not `#[deriving(...)]` for [consistency with other naming
12518 conventions][derive].
12519 * Importing the containing module or enum at the same time as
12520 items or variants they contain is [now done with `self` instead
12521 of `mod`][self], as in use `foo::{self, bar}`
12522 * Glob imports are no longer feature-gated.
12523 * The `box` operator and `box` patterns have been feature-gated
12524 pending a redesign. For now unique boxes should be allocated
12525 like other containers, with `Box::new`.
12526
12527* Libraries
12528
12529 * A [series][coll1] of [efforts][coll2] to establish
12530 [conventions][coll3] for collections types has resulted in API
12531 improvements throughout the standard library.
12532 * New [APIs for error handling][err] provide ergonomic interop
12533 between error types, and [new conventions][err-conv] describe
12534 more clearly the recommended error handling strategies in Rust.
12535 * The `fail!` macro has been renamed to [`panic!`][panic] so that
12536 it is easier to discuss failure in the context of error handling
12537 without making clarifications as to whether you are referring to
12538 the 'fail' macro or failure more generally.
12539 * On Linux, `OsRng` prefers the new, more reliable `getrandom`
12540 syscall when available.
12541 * The 'serialize' crate has been renamed 'rustc-serialize' and
12542 moved out of the distribution to Cargo. Although it is widely
12543 used now, it is expected to be superseded in the near future.
12544 * The `Show` formatter, typically implemented with
12545 `#[derive(Show)]` is [now requested with the `{:?}`
12546 specifier][show] and is intended for use by all types, for uses
12547 such as `println!` debugging. The new `String` formatter must be
12548 implemented by hand, uses the `{}` specifier, and is intended
12549 for full-fidelity conversions of things that can logically be
12550 represented as strings.
12551
12552* Tooling
12553
12554 * [Flexible target specification][flex] allows rustc's code
12555 generation to be configured to support otherwise-unsupported
12556 platforms.
12557 * Rust comes with rust-gdb and rust-lldb scripts that launch their
12558 respective debuggers with Rust-appropriate pretty-printing.
12559 * The Windows installation of Rust is distributed with the
12560 MinGW components currently required to link binaries on that
12561 platform.
12562
12563* Misc
12564
12565 * Nullable enum optimizations have been extended to more types so
12566 that e.g. `Option<Vec<T>>` and `Option<String>` take up no more
12567 space than the inner types themselves.
12568 * Work has begun on supporting AArch64.
12569
12570[Cargo]: https://crates.io
12571[unboxed]: http://smallcultfollowing.com/babysteps/blog/2014/11/26/purging-proc/
12572[enum]: https://github.com/rust-lang/rfcs/blob/master/text/0390-enum-namespacing.md
12573[flex]: https://github.com/rust-lang/rfcs/blob/master/text/0131-target-specification.md
12574[err]: https://github.com/rust-lang/rfcs/blob/master/text/0201-error-chaining.md
12575[err-conv]: https://github.com/rust-lang/rfcs/blob/master/text/0236-error-conventions.md
12576[rt]: https://github.com/rust-lang/rfcs/blob/master/text/0230-remove-runtime.md
12577[mac]: https://github.com/rust-lang/rfcs/blob/master/text/0453-macro-reform.md
12578[mac-future]: https://github.com/rust-lang/rfcs/pull/550
12579[DST]: http://smallcultfollowing.com/babysteps/blog/2014/01/05/dst-take-5/
12580[coll1]: https://github.com/rust-lang/rfcs/blob/master/text/0235-collections-conventions.md
12581[coll2]: https://github.com/rust-lang/rfcs/blob/master/text/0509-collections-reform-part-2.md
12582[coll3]: https://github.com/rust-lang/rfcs/blob/master/text/0216-collection-views.md
12583[ops]: https://github.com/rust-lang/rfcs/blob/master/text/0439-cmp-ops-reform.md
12584[prelude]: https://github.com/rust-lang/rfcs/blob/master/text/0503-prelude-stabilization.md
12585[where]: https://github.com/rust-lang/rfcs/blob/master/text/0135-where.md
12586[refl]: https://github.com/rust-lang/rfcs/blob/master/text/0379-remove-reflection.md
12587[panic]: https://github.com/rust-lang/rfcs/blob/master/text/0221-panic.md
12588[structvars]: https://github.com/rust-lang/rfcs/blob/master/text/0418-struct-variants.md
12589[hrtb]: https://github.com/rust-lang/rfcs/blob/master/text/0387-higher-ranked-trait-bounds.md
12590[unicode]: https://github.com/rust-lang/rfcs/blob/master/text/0446-es6-unicode-escapes.md
12591[oibit]: https://github.com/rust-lang/rfcs/blob/master/text/0019-opt-in-builtin-traits.md
12592[macros]: https://github.com/rust-lang/rfcs/blob/master/text/0378-expr-macros.md
12593[range]: https://github.com/rust-lang/rfcs/blob/master/text/0439-cmp-ops-reform.md#indexing-and-slicing
12594[arrays]: https://github.com/rust-lang/rfcs/blob/master/text/0520-new-array-repeat-syntax.md
12595[show]: https://github.com/rust-lang/rfcs/blob/master/text/0504-show-stabilization.md
12596[derive]: https://github.com/rust-lang/rfcs/blob/master/text/0534-deriving2derive.md
12597[self]: https://github.com/rust-lang/rfcs/blob/master/text/0532-self-in-use.md
12598[fb]: https://github.com/rust-lang/rfcs/blob/master/text/0212-restore-int-fallback.md
12599[objsafe]: https://github.com/rust-lang/rfcs/blob/master/text/0255-object-safety.md
12600[assoc]: https://github.com/rust-lang/rfcs/blob/master/text/0195-associated-items.md
12601[ints]: https://github.com/rust-lang/rfcs/pull/544#issuecomment-68760871
12602[trpl]: https://doc.rust-lang.org/book/index.html
12603[rbe]: http://rustbyexample.com/
12604
12605
12606Version 0.12.0 (2014-10-09)
12607=============================
12608
12609 * ~1900 changes, numerous bugfixes
12610
12611 * Highlights
12612
12613 * The introductory documentation (now called The Rust Guide) has
12614 been completely rewritten, as have a number of supplementary
12615 guides.
12616 * Rust's package manager, Cargo, continues to improve and is
12617 sometimes considered to be quite awesome.
12618 * Many API's in `std` have been reviewed and updated for
12619 consistency with the in-development Rust coding
12620 guidelines. The standard library documentation tracks
12621 stabilization progress.
12622 * Minor libraries have been moved out-of-tree to the rust-lang org
12623 on GitHub: uuid, semver, glob, num, hexfloat, fourcc. They can
12624 be installed with Cargo.
12625 * Lifetime elision allows lifetime annotations to be left off of
12626 function declarations in many common scenarios.
12627 * Rust now works on 64-bit Windows.
12628
12629 * Language
12630 * Indexing can be overloaded with the `Index` and `IndexMut`
12631 traits.
12632 * The `if let` construct takes a branch only if the `let` pattern
12633 matches, currently behind the 'if_let' feature gate.
12634 * 'where clauses', a more flexible syntax for specifying trait
12635 bounds that is more aesthetic, have been added for traits and
12636 free functions. Where clauses will in the future make it
12637 possible to constrain associated types, which would be
12638 impossible with the existing syntax.
12639 * A new slicing syntax (e.g. `[0..4]`) has been introduced behind
12640 the 'slicing_syntax' feature gate, and can be overloaded with
12641 the `Slice` or `SliceMut` traits.
12642 * The syntax for matching of sub-slices has been changed to use a
12643 postfix `..` instead of prefix (.e.g. `[a, b, c..]`), for
12644 consistency with other uses of `..` and to future-proof
12645 potential additional uses of the syntax.
12646 * The syntax for matching inclusive ranges in patterns has changed
12647 from `0..3` to `0...4` to be consistent with the exclusive range
12648 syntax for slicing.
12649 * Matching of sub-slices in non-tail positions (e.g. `[a.., b,
12650 c]`) has been put behind the 'advanced_slice_patterns' feature
12651 gate and may be removed in the future.
12652 * Components of tuples and tuple structs can be extracted using
12653 the `value.0` syntax, currently behind the `tuple_indexing`
12654 feature gate.
12655 * The `#[crate_id]` attribute is no longer supported; versioning
12656 is handled by the package manager.
12657 * Renaming crate imports are now written `extern crate foo as bar`
12658 instead of `extern crate bar = foo`.
12659 * Renaming use statements are now written `use foo as bar` instead
12660 of `use bar = foo`.
12661 * `let` and `match` bindings and argument names in macros are now
12662 hygienic.
12663 * The new, more efficient, closure types ('unboxed closures') have
12664 been added under a feature gate, 'unboxed_closures'. These will
12665 soon replace the existing closure types, once higher-ranked
12666 trait lifetimes are added to the language.
12667 * `move` has been added as a keyword, for indicating closures
12668 that capture by value.
12669 * Mutation and assignment is no longer allowed in pattern guards.
12670 * Generic structs and enums can now have trait bounds.
12671 * The `Share` trait is now called `Sync` to free up the term
12672 'shared' to refer to 'shared reference' (the default reference
12673 type.
12674 * Dynamically-sized types have been mostly implemented,
12675 unifying the behavior of fat-pointer types with the rest of the
12676 type system.
12677 * As part of dynamically-sized types, the `Sized` trait has been
12678 introduced, which qualifying types implement by default, and
12679 which type parameters expect by default. To specify that a type
12680 parameter does not need to be sized, write `<Sized? T>`. Most
12681 types are `Sized`, notable exceptions being unsized arrays
12682 (`[T]`) and trait types.
12683 * Closures can return `!`, as in `|| -> !` or `proc() -> !`.
12684 * Lifetime bounds can now be applied to type parameters and object
12685 types.
12686 * The old, reference counted GC type, `Gc<T>` which was once
12687 denoted by the `@` sigil, has finally been removed. GC will be
12688 revisited in the future.
12689
12690 * Libraries
12691 * Library documentation has been improved for a number of modules.
12692 * Bit-vectors, collections::bitv has been modernized.
12693 * The url crate is deprecated in favor of
12694 http://github.com/servo/rust-url, which can be installed with
12695 Cargo.
12696 * Most I/O stream types can be cloned and subsequently closed from
12697 a different thread.
12698 * A `std::time::Duration` type has been added for use in I/O
12699 methods that rely on timers, as well as in the 'time' crate's
12700 `Timespec` arithmetic.
12701 * The runtime I/O abstraction layer that enabled the green thread
12702 scheduler to do non-thread-blocking I/O has been removed, along
12703 with the libuv-based implementation employed by the green thread
12704 scheduler. This will greatly simplify the future I/O work.
12705 * `collections::btree` has been rewritten to have a more
12706 idiomatic and efficient design.
12707
12708 * Tooling
12709 * rustdoc output now indicates the stability levels of API's.
12710 * The `--crate-name` flag can specify the name of the crate
12711 being compiled, like `#[crate_name]`.
12712 * The `-C metadata` specifies additional metadata to hash into
12713 symbol names, and `-C extra-filename` specifies additional
12714 information to put into the output filename, for use by the
12715 package manager for versioning.
12716 * debug info generation has continued to improve and should be
12717 more reliable under both gdb and lldb.
12718 * rustc has experimental support for compiling in parallel
12719 using the `-C codegen-units` flag.
12720 * rustc no longer encodes rpath information into binaries by
12721 default.
12722
12723 * Misc
12724 * Stack usage has been optimized with LLVM lifetime annotations.
12725 * Official Rust binaries on Linux are more compatible with older
12726 kernels and distributions, built on CentOS 5.10.
12727
12728
12729Version 0.11.0 (2014-07-02)
12730==========================
12731
12732 * ~1700 changes, numerous bugfixes
12733
12734 * Language
12735 * ~[T] has been removed from the language. This type is superseded by
12736 the Vec<T> type.
12737 * ~str has been removed from the language. This type is superseded by
12738 the String type.
12739 * ~T has been removed from the language. This type is superseded by the
12740 Box<T> type.
12741 * @T has been removed from the language. This type is superseded by the
12742 standard library's std::gc::Gc<T> type.
12743 * Struct fields are now all private by default.
12744 * Vector indices and shift amounts are both required to be a `uint`
12745 instead of any integral type.
12746 * Byte character, byte string, and raw byte string literals are now all
12747 supported by prefixing the normal literal with a `b`.
12748 * Multiple ABIs are no longer allowed in an ABI string
12749 * The syntax for lifetimes on closures/procedures has been tweaked
12750 slightly: `<'a>|A, B|: 'b + K -> T`
12751 * Floating point modulus has been removed from the language; however it
12752 is still provided by a library implementation.
12753 * Private enum variants are now disallowed.
12754 * The `priv` keyword has been removed from the language.
12755 * A closure can no longer be invoked through a &-pointer.
12756 * The `use foo, bar, baz;` syntax has been removed from the language.
12757 * The transmute intrinsic no longer works on type parameters.
12758 * Statics now allow blocks/items in their definition.
12759 * Trait bounds are separated from objects with + instead of : now.
12760 * Objects can no longer be read while they are mutably borrowed.
12761 * The address of a static is now marked as insignificant unless the
12762 #[inline(never)] attribute is placed it.
12763 * The #[unsafe_destructor] attribute is now behind a feature gate.
12764 * Struct literals are no longer allowed in ambiguous positions such as
12765 if, while, match, and for..in.
12766 * Declaration of lang items and intrinsics are now feature-gated by
12767 default.
12768 * Integral literals no longer default to `int`, and floating point
12769 literals no longer default to `f64`. Literals must be suffixed with an
12770 appropriate type if inference cannot determine the type of the
12771 literal.
12772 * The Box<T> type is no longer implicitly borrowed to &mut T.
12773 * Procedures are now required to not capture borrowed references.
12774
12775 * Libraries
12776 * The standard library is now a "facade" over a number of underlying
12777 libraries. This means that development on the standard library should
12778 be speedier due to smaller crates, as well as a clearer line between
12779 all dependencies.
12780 * A new library, libcore, lives under the standard library's facade
12781 which is Rust's "0-assumption" library, suitable for embedded and
12782 kernel development for example.
12783 * A regex crate has been added to the standard distribution. This crate
12784 includes statically compiled regular expressions.
12785 * The unwrap/unwrap_err methods on Result require a Show bound for
12786 better error messages.
12787 * The return types of the std::comm primitives have been centralized
12788 around the Result type.
12789 * A number of I/O primitives have gained the ability to time out their
12790 operations.
12791 * A number of I/O primitives have gained the ability to close their
12792 reading/writing halves to cancel pending operations.
12793 * Reverse iterator methods have been removed in favor of `rev()` on
12794 their forward-iteration counterparts.
12795 * A bitflags! macro has been added to enable easy interop with C and
12796 management of bit flags.
12797 * A debug_assert! macro is now provided which is disabled when
12798 `--cfg ndebug` is passed to the compiler.
12799 * A graphviz crate has been added for creating .dot files.
12800 * The std::cast module has been migrated into std::mem.
12801 * The std::local_data api has been migrated from freestanding functions
12802 to being based on methods.
12803 * The Pod trait has been renamed to Copy.
12804 * jemalloc has been added as the default allocator for types.
12805 * The API for allocating memory has been changed to use proper alignment
12806 and sized deallocation
12807 * Connecting a TcpStream or binding a TcpListener is now based on a
12808 string address and a u16 port. This allows connecting to a hostname as
12809 opposed to an IP.
12810 * The Reader trait now contains a core method, read_at_least(), which
12811 correctly handles many repeated 0-length reads.
12812 * The process-spawning API is now centered around a builder-style
12813 Command struct.
12814 * The :? printing qualifier has been moved from the standard library to
12815 an external libdebug crate.
12816 * Eq/Ord have been renamed to PartialEq/PartialOrd. TotalEq/TotalOrd
12817 have been renamed to Eq/Ord.
12818 * The select/plural methods have been removed from format!. The escapes
12819 for { and } have also changed from \{ and \} to {{ and }},
12820 respectively.
12821 * The TaskBuilder API has been re-worked to be a true builder, and
12822 extension traits for spawning native/green tasks have been added.
12823
12824 * Tooling
12825 * All breaking changes to the language or libraries now have their
12826 commit message annotated with `[breaking-change]` to allow for easy
12827 discovery of breaking changes.
12828 * The compiler will now try to suggest how to annotate lifetimes if a
12829 lifetime-related error occurs.
12830 * Debug info continues to be improved greatly with general bug fixes and
12831 better support for situations like link time optimization (LTO).
12832 * Usage of syntax extensions when cross-compiling has been fixed.
12833 * Functionality equivalent to GCC & Clang's -ffunction-sections,
12834 -fdata-sections and --gc-sections has been enabled by default
12835 * The compiler is now stricter about where it will load module files
12836 from when a module is declared via `mod foo;`.
12837 * The #[phase(syntax)] attribute has been renamed to #[phase(plugin)].
12838 Syntax extensions are now discovered via a "plugin registrar" type
12839 which will be extended in the future to other various plugins.
12840 * Lints have been restructured to allow for dynamically loadable lints.
12841 * A number of rustdoc improvements:
12842 * The HTML output has been visually redesigned.
12843 * Markdown is now powered by hoedown instead of sundown.
12844 * Searching heuristics have been greatly improved.
12845 * The search index has been reduced in size by a great amount.
12846 * Cross-crate documentation via `pub use` has been greatly improved.
12847 * Primitive types are now hyperlinked and documented.
12848 * Documentation has been moved from static.rust-lang.org/doc to
12849 doc.rust-lang.org
12850 * A new sandbox, play.rust-lang.org, is available for running and
12851 sharing rust code examples on-line.
12852 * Unused attributes are now more robustly warned about.
12853 * The dead_code lint now warns about unused struct fields.
12854 * Cross-compiling to iOS is now supported.
12855 * Cross-compiling to mipsel is now supported.
12856 * Stability attributes are now inherited by default and no longer apply
12857 to intra-crate usage, only inter-crate usage.
12858 * Error message related to non-exhaustive match expressions have been
12859 greatly improved.
12860
12861
12862Version 0.10 (2014-04-03)
12863=========================
12864
12865 * ~1500 changes, numerous bugfixes
12866
12867 * Language
12868 * A new RFC process is now in place for modifying the language.
12869 * Patterns with `@`-pointers have been removed from the language.
12870 * Patterns with unique vectors (`~[T]`) have been removed from the
12871 language.
12872 * Patterns with unique strings (`~str`) have been removed from the
12873 language.
12874 * `@str` has been removed from the language.
12875 * `@[T]` has been removed from the language.
12876 * `@self` has been removed from the language.
12877 * `@Trait` has been removed from the language.
12878 * Headers on `~` allocations which contain `@` boxes inside the type for
12879 reference counting have been removed.
12880 * The semantics around the lifetimes of temporary expressions have changed,
12881 see #3511 and #11585 for more information.
12882 * Cross-crate syntax extensions are now possible, but feature gated. See
12883 #11151 for more information. This includes both `macro_rules!` macros as
12884 well as syntax extensions such as `format!`.
12885 * New lint modes have been added, and older ones have been turned on to be
12886 warn-by-default.
12887 * Unnecessary parentheses
12888 * Uppercase statics
12889 * Camel Case types
12890 * Uppercase variables
12891 * Publicly visible private types
12892 * `#[deriving]` with raw pointers
12893 * Unsafe functions can no longer be coerced to closures.
12894 * Various obscure macros such as `log_syntax!` are now behind feature gates.
12895 * The `#[simd]` attribute is now behind a feature gate.
12896 * Visibility is no longer allowed on `extern crate` statements, and
12897 unnecessary visibility (`priv`) is no longer allowed on `use` statements.
12898 * Trailing commas are now allowed in argument lists and tuple patterns.
12899 * The `do` keyword has been removed, it is now a reserved keyword.
12900 * Default type parameters have been implemented, but are feature gated.
12901 * Borrowed variables through captures in closures are now considered soundly.
12902 * `extern mod` is now `extern crate`
12903 * The `Freeze` trait has been removed.
12904 * The `Share` trait has been added for types that can be shared among
12905 threads.
12906 * Labels in macros are now hygienic.
12907 * Expression/statement macro invocations can be delimited with `{}` now.
12908 * Treatment of types allowed in `static mut` locations has been tweaked.
12909 * The `*` and `.` operators are now overloadable through the `Deref` and
12910 `DerefMut` traits.
12911 * `~Trait` and `proc` no longer have `Send` bounds by default.
12912 * Partial type hints are now supported with the `_` type marker.
12913 * An `Unsafe` type was introduced for interior mutability. It is now
12914 considered undefined to transmute from `&T` to `&mut T` without using the
12915 `Unsafe` type.
12916 * The #[linkage] attribute was implemented for extern statics/functions.
12917 * The inner attribute syntax has changed from `#[foo];` to `#![foo]`.
12918 * `Pod` was renamed to `Copy`.
12919
12920 * Libraries
12921 * The `libextra` library has been removed. It has now been decomposed into
12922 component libraries with smaller and more focused nuggets of
12923 functionality. The full list of libraries can be found on the
12924 documentation index page.
12925 * std: `std::condition` has been removed. All I/O errors are now propagated
12926 through the `Result` type. In order to assist with error handling, a
12927 `try!` macro for unwrapping errors with an early return and a lint for
12928 unused results has been added. See #12039 for more information.
12929 * std: The `vec` module has been renamed to `slice`.
12930 * std: A new vector type, `Vec<T>`, has been added in preparation for DST.
12931 This will become the only growable vector in the future.
12932 * std: `std::io` now has more public re-exports. Types such as `BufferedReader`
12933 are now found at `std::io::BufferedReader` instead of
12934 `std::io::buffered::BufferedReader`.
12935 * std: `print` and `println` are no longer in the prelude, the `print!` and
12936 `println!` macros are intended to be used instead.
12937 * std: `Rc` now has a `Weak` pointer for breaking cycles, and it no longer
12938 attempts to statically prevent cycles.
12939 * std: The standard distribution is adopting the policy of pushing failure
12940 to the user rather than failing in libraries. Many functions (such as
12941 `slice::last()`) now return `Option<T>` instead of `T` + failing.
12942 * std: `fmt::Default` has been renamed to `fmt::Show`, and it now has a new
12943 deriving mode: `#[deriving(Show)]`.
12944 * std: `ToStr` is now implemented for all types implementing `Show`.
12945 * std: The formatting trait methods now take `&self` instead of `&T`
12946 * std: The `invert()` method on iterators has been renamed to `rev()`
12947 * std: `std::num` has seen a reduction in the genericity of its traits,
12948 consolidating functionality into a few core traits.
12949 * std: Backtraces are now printed on task failure if the environment
12950 variable `RUST_BACKTRACE` is present.
12951 * std: Naming conventions for iterators have been standardized. More details
12952 can be found on the wiki's style guide.
12953 * std: `eof()` has been removed from the `Reader` trait. Specific types may
12954 still implement the function.
12955 * std: Networking types are now cloneable to allow simultaneous reads/writes.
12956 * std: `assert_approx_eq!` has been removed
12957 * std: The `e` and `E` formatting specifiers for floats have been added to
12958 print them in exponential notation.
12959 * std: The `Times` trait has been removed
12960 * std: Indications of variance and opting out of builtin bounds is done
12961 through marker types in `std::kinds::marker` now
12962 * std: `hash` has been rewritten, `IterBytes` has been removed, and
12963 `#[deriving(Hash)]` is now possible.
12964 * std: `SharedChan` has been removed, `Sender` is now cloneable.
12965 * std: `Chan` and `Port` were renamed to `Sender` and `Receiver`.
12966 * std: `Chan::new` is now `channel()`.
12967 * std: A new synchronous channel type has been implemented.
12968 * std: A `select!` macro is now provided for selecting over `Receiver`s.
12969 * std: `hashmap` and `trie` have been moved to `libcollections`
12970 * std: `run` has been rolled into `io::process`
12971 * std: `assert_eq!` now uses `{}` instead of `{:?}`
12972 * std: The equality and comparison traits have seen some reorganization.
12973 * std: `rand` has moved to `librand`.
12974 * std: `to_{lower,upper}case` has been implemented for `char`.
12975 * std: Logging has been moved to `liblog`.
12976 * collections: `HashMap` has been rewritten for higher performance and less
12977 memory usage.
12978 * native: The default runtime is now `libnative`. If `libgreen` is desired,
12979 it can be booted manually. The runtime guide has more information and
12980 examples.
12981 * native: All I/O functionality except signals has been implemented.
12982 * green: Task spawning with `libgreen` has been optimized with stack caching
12983 and various trimming of code.
12984 * green: Tasks spawned by `libgreen` now have an unmapped guard page.
12985 * sync: The `extra::sync` module has been updated to modern rust (and moved
12986 to the `sync` library), tweaking and improving various interfaces while
12987 dropping redundant functionality.
12988 * sync: A new `Barrier` type has been added to the `sync` library.
12989 * sync: An efficient mutex for native and green tasks has been implemented.
12990 * serialize: The `base64` module has seen some improvement. It treats
12991 newlines better, has non-string error values, and has seen general
12992 cleanup.
12993 * fourcc: A `fourcc!` macro was introduced
12994 * hexfloat: A `hexfloat!` macro was implemented for specifying floats via a
12995 hexadecimal literal.
12996
12997 * Tooling
12998 * `rustpkg` has been deprecated and removed from the main repository. Its
12999 replacement, `cargo`, is under development.
13000 * Nightly builds of rust are now available
13001 * The memory usage of rustc has been improved many times throughout this
13002 release cycle.
13003 * The build process supports disabling rpath support for the rustc binary
13004 itself.
13005 * Code generation has improved in some cases, giving more information to the
13006 LLVM optimization passes to enable more extensive optimizations.
13007 * Debuginfo compatibility with lldb on OSX has been restored.
13008 * The master branch is now gated on an android bot, making building for
13009 android much more reliable.
13010 * Output flags have been centralized into one `--emit` flag.
13011 * Crate type flags have been centralized into one `--crate-type` flag.
13012 * Codegen flags have been consolidated behind a `-C` flag.
13013 * Linking against outdated crates now has improved error messages.
13014 * Error messages with lifetimes will often suggest how to annotate the
13015 function to fix the error.
13016 * Many more types are documented in the standard library, and new guides
13017 were written.
13018 * Many `rustdoc` improvements:
13019 * code blocks are syntax highlighted.
13020 * render standalone markdown files.
13021 * the --test flag tests all code blocks by default.
13022 * exported macros are displayed.
13023 * re-exported types have their documentation inlined at the location of the
13024 first re-export.
13025 * search works across crates that have been rendered to the same output
13026 directory.
13027
13028
13029Version 0.9 (2014-01-09)
13030==========================
13031
13032 * ~1800 changes, numerous bugfixes
13033
13034 * Language
13035 * The `float` type has been removed. Use `f32` or `f64` instead.
13036 * A new facility for enabling experimental features (feature gating) has
13037 been added, using the crate-level `#[feature(foo)]` attribute.
13038 * Managed boxes (@) are now behind a feature gate
13039 (`#[feature(managed_boxes)]`) in preparation for future removal. Use the
13040 standard library's `Gc` or `Rc` types instead.
13041 * `@mut` has been removed. Use `std::cell::{Cell, RefCell}` instead.
13042 * Jumping back to the top of a loop is now done with `continue` instead of
13043 `loop`.
13044 * Strings can no longer be mutated through index assignment.
13045 * Raw strings can be created via the basic `r"foo"` syntax or with matched
13046 hash delimiters, as in `r###"foo"###`.
13047 * `~fn` is now written `proc (args) -> retval { ... }` and may only be
13048 called once.
13049 * The `&fn` type is now written `|args| -> ret` to match the literal form.
13050 * `@fn`s have been removed.
13051 * `do` only works with procs in order to make it obvious what the cost
13052 of `do` is.
13053 * Single-element tuple-like structs can no longer be dereferenced to
13054 obtain the inner value. A more comprehensive solution for overloading
13055 the dereference operator will be provided in the future.
13056 * The `#[link(...)]` attribute has been replaced with
13057 `#[crate_id = "name#vers"]`.
13058 * Empty `impl`s must be terminated with empty braces and may not be
13059 terminated with a semicolon.
13060 * Keywords are no longer allowed as lifetime names; the `self` lifetime
13061 no longer has any special meaning.
13062 * The old `fmt!` string formatting macro has been removed.
13063 * `printf!` and `printfln!` (old-style formatting) removed in favor of
13064 `print!` and `println!`.
13065 * `mut` works in patterns now, as in `let (mut x, y) = (1, 2);`.
13066 * The `extern mod foo (name = "bar")` syntax has been removed. Use
13067 `extern mod foo = "bar"` instead.
13068 * New reserved keywords: `alignof`, `offsetof`, `sizeof`.
13069 * Macros can have attributes.
13070 * Macros can expand to items with attributes.
13071 * Macros can expand to multiple items.
13072 * The `asm!` macro is feature-gated (`#[feature(asm)]`).
13073 * Comments may be nested.
13074 * Values automatically coerce to trait objects they implement, without
13075 an explicit `as`.
13076 * Enum discriminants are no longer an entire word but as small as needed to
13077 contain all the variants. The `repr` attribute can be used to override
13078 the discriminant size, as in `#[repr(int)]` for integer-sized, and
13079 `#[repr(C)]` to match C enums.
13080 * Non-string literals are not allowed in attributes (they never worked).
13081 * The FFI now supports variadic functions.
13082 * Octal numeric literals, as in `0o7777`.
13083 * The `concat!` syntax extension performs compile-time string concatenation.
13084 * The `#[fixed_stack_segment]` and `#[rust_stack]` attributes have been
13085 removed as Rust no longer uses segmented stacks.
13086 * Non-ascii identifiers are feature-gated (`#[feature(non_ascii_idents)]`).
13087 * Ignoring all fields of an enum variant or tuple-struct is done with `..`,
13088 not `*`; ignoring remaining fields of a struct is also done with `..`,
13089 not `_`; ignoring a slice of a vector is done with `..`, not `.._`.
13090 * `rustc` supports the "win64" calling convention via `extern "win64"`.
13091 * `rustc` supports the "system" calling convention, which defaults to the
13092 preferred convention for the target platform, "stdcall" on 32-bit Windows,
13093 "C" elsewhere.
13094 * The `type_overflow` lint (default: warn) checks literals for overflow.
13095 * The `unsafe_block` lint (default: allow) checks for usage of `unsafe`.
13096 * The `attribute_usage` lint (default: warn) warns about unknown
13097 attributes.
13098 * The `unknown_features` lint (default: warn) warns about unknown
13099 feature gates.
13100 * The `dead_code` lint (default: warn) checks for dead code.
13101 * Rust libraries can be linked statically to one another
13102 * `#[link_args]` is behind the `link_args` feature gate.
13103 * Native libraries are now linked with `#[link(name = "foo")]`
13104 * Native libraries can be statically linked to a rust crate
13105 (`#[link(name = "foo", kind = "static")]`).
13106 * Native OS X frameworks are now officially supported
13107 (`#[link(name = "foo", kind = "framework")]`).
13108 * The `#[thread_local]` attribute creates thread-local (not task-local)
13109 variables. Currently behind the `thread_local` feature gate.
13110 * The `return` keyword may be used in closures.
13111 * Types that can be copied via a memcpy implement the `Pod` kind.
13112 * The `cfg` attribute can now be used on struct fields and enum variants.
13113
13114 * Libraries
13115 * std: The `option` and `result` API's have been overhauled to make them
13116 simpler, more consistent, and more composable.
13117 * std: The entire `std::io` module has been replaced with one that is
13118 more comprehensive and that properly interfaces with the underlying
13119 scheduler. File, TCP, UDP, Unix sockets, pipes, and timers are all
13120 implemented.
13121 * std: `io::util` contains a number of useful implementations of
13122 `Reader` and `Writer`, including `NullReader`, `NullWriter`,
13123 `ZeroReader`, `TeeReader`.
13124 * std: The reference counted pointer type `extra::rc` moved into std.
13125 * std: The `Gc` type in the `gc` module will replace `@` (it is currently
13126 just a wrapper around it).
13127 * std: The `Either` type has been removed.
13128 * std: `fmt::Default` can be implemented for any type to provide default
13129 formatting to the `format!` macro, as in `format!("{}", myfoo)`.
13130 * std: The `rand` API continues to be tweaked.
13131 * std: The `rust_begin_unwind` function, useful for inserting breakpoints
13132 on failure in gdb, is now named `rust_fail`.
13133 * std: The `each_key` and `each_value` methods on `HashMap` have been
13134 replaced by the `keys` and `values` iterators.
13135 * std: Functions dealing with type size and alignment have moved from the
13136 `sys` module to the `mem` module.
13137 * std: The `path` module was written and API changed.
13138 * std: `str::from_utf8` has been changed to cast instead of allocate.
13139 * std: `starts_with` and `ends_with` methods added to vectors via the
13140 `ImmutableEqVector` trait, which is in the prelude.
13141 * std: Vectors can be indexed with the `get_opt` method, which returns `None`
13142 if the index is out of bounds.
13143 * std: Task failure no longer propagates between tasks, as the model was
13144 complex, expensive, and incompatible with thread-based tasks.
13145 * std: The `Any` type can be used for dynamic typing.
13146 * std: `~Any` can be passed to the `fail!` macro and retrieved via
13147 `task::try`.
13148 * std: Methods that produce iterators generally do not have an `_iter`
13149 suffix now.
13150 * std: `cell::Cell` and `cell::RefCell` can be used to introduce mutability
13151 roots (mutable fields, etc.). Use instead of e.g. `@mut`.
13152 * std: `util::ignore` renamed to `prelude::drop`.
13153 * std: Slices have `sort` and `sort_by` methods via the `MutableVector`
13154 trait.
13155 * std: `vec::raw` has seen a lot of cleanup and API changes.
13156 * std: The standard library no longer includes any C++ code, and very
13157 minimal C, eliminating the dependency on libstdc++.
13158 * std: Runtime scheduling and I/O functionality has been factored out into
13159 extensible interfaces and is now implemented by two different crates:
13160 libnative, for native threading and I/O; and libgreen, for green threading
13161 and I/O. This paves the way for using the standard library in more limited
13162 embedded environments.
13163 * std: The `comm` module has been rewritten to be much faster, have a
13164 simpler, more consistent API, and to work for both native and green
13165 threading.
13166 * std: All libuv dependencies have been moved into the rustuv crate.
13167 * native: New implementations of runtime scheduling on top of OS threads.
13168 * native: New native implementations of TCP, UDP, file I/O, process spawning,
13169 and other I/O.
13170 * green: The green thread scheduler and message passing types are almost
13171 entirely lock-free.
13172 * extra: The `flatpipes` module had bitrotted and was removed.
13173 * extra: All crypto functions have been removed and Rust now has a policy of
13174 not reimplementing crypto in the standard library. In the future crypto
13175 will be provided by external crates with bindings to established libraries.
13176 * extra: `c_vec` has been modernized.
13177 * extra: The `sort` module has been removed. Use the `sort` method on
13178 mutable slices.
13179
13180 * Tooling
13181 * The `rust` and `rusti` commands have been removed, due to lack of
13182 maintenance.
13183 * `rustdoc` was completely rewritten.
13184 * `rustdoc` can test code examples in documentation.
13185 * `rustpkg` can test packages with the argument, 'test'.
13186 * `rustpkg` supports arbitrary dependencies, including C libraries.
13187 * `rustc`'s support for generating debug info is improved again.
13188 * `rustc` has better error reporting for unbalanced delimiters.
13189 * `rustc`'s JIT support was removed due to bitrot.
13190 * Executables and static libraries can be built with LTO (-Z lto)
13191 * `rustc` adds a `--dep-info` flag for communicating dependencies to
13192 build tools.
13193
13194
13195Version 0.8 (2013-09-26)
13196============================
13197
13198 * ~2200 changes, numerous bugfixes
13199
13200 * Language
13201 * The `for` loop syntax has changed to work with the `Iterator` trait.
13202 * At long last, unwinding works on Windows.
13203 * Default methods are ready for use.
13204 * Many trait inheritance bugs fixed.
13205 * Owned and borrowed trait objects work more reliably.
13206 * `copy` is no longer a keyword. It has been replaced by the `Clone` trait.
13207 * rustc can omit emission of code for the `debug!` macro if it is passed
13208 `--cfg ndebug`
13209 * mod.rs is now "blessed". When loading `mod foo;`, rustc will now look
13210 for foo.rs, then foo/mod.rs, and will generate an error when both are
13211 present.
13212 * Strings no longer contain trailing nulls. The new `std::c_str` module
13213 provides new mechanisms for converting to C strings.
13214 * The type of foreign functions is now `extern "C" fn` instead of `*u8'.
13215 * The FFI has been overhauled such that foreign functions are called directly,
13216 instead of through a stack-switching wrapper.
13217 * Calling a foreign function must be done through a Rust function with the
13218 `#[fixed_stack_segment]` attribute.
13219 * The `externfn!` macro can be used to declare both a foreign function and
13220 a `#[fixed_stack_segment]` wrapper at once.
13221 * `pub` and `priv` modifiers on `extern` blocks are no longer parsed.
13222 * `unsafe` is no longer allowed on extern fns - they are all unsafe.
13223 * `priv` is disallowed everywhere except for struct fields and enum variants.
13224 * `&T` (besides `&'static T`) is no longer allowed in `@T`.
13225 * `ref` bindings in irrefutable patterns work correctly now.
13226 * `char` is now prevented from containing invalid code points.
13227 * Casting to `bool` is no longer allowed.
13228 * `\0` is now accepted as an escape in chars and strings.
13229 * `yield` is a reserved keyword.
13230 * `typeof` is a reserved keyword.
13231 * Crates may be imported by URL with `extern mod foo = "url";`.
13232 * Explicit enum discriminants may be given as uints as in `enum E { V = 0u }`
13233 * Static vectors can be initialized with repeating elements,
13234 e.g. `static foo: [u8, .. 100]: [0, .. 100];`.
13235 * Static structs can be initialized with functional record update,
13236 e.g. `static foo: Foo = Foo { a: 5, .. bar };`.
13237 * `cfg!` can be used to conditionally execute code based on the crate
13238 configuration, similarly to `#[cfg(...)]`.
13239 * The `unnecessary_qualification` lint detects unneeded module
13240 prefixes (default: allow).
13241 * Arithmetic operations have been implemented on the SIMD types in
13242 `std::unstable::simd`.
13243 * Exchange allocation headers were removed, reducing memory usage.
13244 * `format!` implements a completely new, extensible, and higher-performance
13245 string formatting system. It will replace `fmt!`.
13246 * `print!` and `println!` write formatted strings (using the `format!`
13247 extension) to stdout.
13248 * `write!` and `writeln!` write formatted strings (using the `format!`
13249 extension) to the new Writers in `std::rt::io`.
13250 * The library section in which a function or static is placed may
13251 be specified with `#[link_section = "..."]`.
13252 * The `proto!` syntax extension for defining bounded message protocols
13253 was removed.
13254 * `macro_rules!` is hygienic for `let` declarations.
13255 * The `#[export_name]` attribute specifies the name of a symbol.
13256 * `unreachable!` can be used to indicate unreachable code, and fails
13257 if executed.
13258
13259 * Libraries
13260 * std: Transitioned to the new runtime, written in Rust.
13261 * std: Added an experimental I/O library, `rt::io`, based on the new
13262 runtime.
13263 * std: A new generic `range` function was added to the prelude, replacing
13264 `uint::range` and friends.
13265 * std: `range_rev` no longer exists. Since range is an iterator it can be
13266 reversed with `range(lo, hi).invert()`.
13267 * std: The `chain` method on option renamed to `and_then`; `unwrap_or_default`
13268 renamed to `unwrap_or`.
13269 * std: The `iterator` module was renamed to `iter`.
13270 * std: Integral types now support the `checked_add`, `checked_sub`, and
13271 `checked_mul` operations for detecting overflow.
13272 * std: Many methods in `str`, `vec`, `option, `result` were renamed for
13273 consistency.
13274 * std: Methods are standardizing on conventions for casting methods:
13275 `to_foo` for copying, `into_foo` for moving, `as_foo` for temporary
13276 and cheap casts.
13277 * std: The `CString` type in `c_str` provides new ways to convert to and
13278 from C strings.
13279 * std: `DoubleEndedIterator` can yield elements in two directions.
13280 * std: The `mut_split` method on vectors partitions an `&mut [T]` into
13281 two splices.
13282 * std: `str::from_bytes` renamed to `str::from_utf8`.
13283 * std: `pop_opt` and `shift_opt` methods added to vectors.
13284 * std: The task-local data interface no longer uses @, and keys are
13285 no longer function pointers.
13286 * std: The `swap_unwrap` method of `Option` renamed to `take_unwrap`.
13287 * std: Added `SharedPort` to `comm`.
13288 * std: `Eq` has a default method for `ne`; only `eq` is required
13289 in implementations.
13290 * std: `Ord` has default methods for `le`, `gt` and `ge`; only `lt`
13291 is required in implementations.
13292 * std: `is_utf8` performance is improved, impacting many string functions.
13293 * std: `os::MemoryMap` provides cross-platform mmap.
13294 * std: `ptr::offset` is now unsafe, but also more optimized. Offsets that
13295 are not 'in-bounds' are considered undefined.
13296 * std: Many freestanding functions in `vec` removed in favor of methods.
13297 * std: Many freestanding functions on scalar types removed in favor of
13298 methods.
13299 * std: Many options to task builders were removed since they don't make
13300 sense in the new scheduler design.
13301 * std: More containers implement `FromIterator` so can be created by the
13302 `collect` method.
13303 * std: More complete atomic types in `unstable::atomics`.
13304 * std: `comm::PortSet` removed.
13305 * std: Mutating methods in the `Set` and `Map` traits have been moved into
13306 the `MutableSet` and `MutableMap` traits. `Container::is_empty`,
13307 `Map::contains_key`, `MutableMap::insert`, and `MutableMap::remove` have
13308 default implementations.
13309 * std: Various `from_str` functions were removed in favor of a generic
13310 `from_str` which is available in the prelude.
13311 * std: `util::unreachable` removed in favor of the `unreachable!` macro.
13312 * extra: `dlist`, the doubly-linked list was modernized.
13313 * extra: Added a `hex` module with `ToHex` and `FromHex` traits.
13314 * extra: Added `glob` module, replacing `std::os::glob`.
13315 * extra: `rope` was removed.
13316 * extra: `deque` was renamed to `ringbuf`. `RingBuf` implements `Deque`.
13317 * extra: `net`, and `timer` were removed. The experimental replacements
13318 are `std::rt::io::net` and `std::rt::io::timer`.
13319 * extra: Iterators implemented for `SmallIntMap`.
13320 * extra: Iterators implemented for `Bitv` and `BitvSet`.
13321 * extra: `SmallIntSet` removed. Use `BitvSet`.
13322 * extra: Performance of JSON parsing greatly improved.
13323 * extra: `semver` updated to SemVer 2.0.0.
13324 * extra: `term` handles more terminals correctly.
13325 * extra: `dbg` module removed.
13326 * extra: `par` module removed.
13327 * extra: `future` was cleaned up, with some method renames.
13328 * extra: Most free functions in `getopts` were converted to methods.
13329
13330 * Other
13331 * rustc's debug info generation (`-Z debug-info`) is greatly improved.
13332 * rustc accepts `--target-cpu` to compile to a specific CPU architecture,
13333 similarly to gcc's `--march` flag.
13334 * rustc's performance compiling small crates is much better.
13335 * rustpkg has received many improvements.
13336 * rustpkg supports git tags as package IDs.
13337 * rustpkg builds into target-specific directories so it can be used for
13338 cross-compiling.
13339 * The number of concurrent test tasks is controlled by the environment
13340 variable RUST_TEST_TASKS.
13341 * The test harness can now report metrics for benchmarks.
13342 * All tools have man pages.
13343 * Programs compiled with `--test` now support the `-h` and `--help` flags.
13344 * The runtime uses jemalloc for allocations.
13345 * Segmented stacks are temporarily disabled as part of the transition to
13346 the new runtime. Stack overflows are possible!
13347 * A new documentation backend, rustdoc_ng, is available for use. It is
13348 still invoked through the normal `rustdoc` command.
13349
13350
13351Version 0.7 (2013-07-03)
13352=======================
13353
13354 * ~2000 changes, numerous bugfixes
13355
13356 * Language
13357 * `impl`s no longer accept a visibility qualifier. Put them on methods
13358 instead.
13359 * The borrow checker has been rewritten with flow-sensitivity, fixing
13360 many bugs and inconveniences.
13361 * The `self` parameter no longer implicitly means `&'self self`,
13362 and can be explicitly marked with a lifetime.
13363 * Overloadable compound operators (`+=`, etc.) have been temporarily
13364 removed due to bugs.
13365 * The `for` loop protocol now requires `for`-iterators to return `bool`
13366 so they compose better.
13367 * The `Durable` trait is replaced with the `'static` bounds.
13368 * Trait default methods work more often.
13369 * Structs with the `#[packed]` attribute have byte alignment and
13370 no padding between fields.
13371 * Type parameters bound by `Copy` must now be copied explicitly with
13372 the `copy` keyword.
13373 * It is now illegal to move out of a dereferenced unsafe pointer.
13374 * `Option<~T>` is now represented as a nullable pointer.
13375 * `@mut` does dynamic borrow checks correctly.
13376 * The `main` function is only detected at the topmost level of the crate.
13377 The `#[main]` attribute is still valid anywhere.
13378 * Struct fields may no longer be mutable. Use inherited mutability.
13379 * The `#[no_send]` attribute makes a type that would otherwise be
13380 `Send`, not.
13381 * The `#[no_freeze]` attribute makes a type that would otherwise be
13382 `Freeze`, not.
13383 * Unbounded recursion will abort the process after reaching the limit
13384 specified by the `RUST_MAX_STACK` environment variable (default: 1GB).
13385 * The `vecs_implicitly_copyable` lint mode has been removed. Vectors
13386 are never implicitly copyable.
13387 * `#[static_assert]` makes compile-time assertions about static bools.
13388 * At long last, 'argument modes' no longer exist.
13389 * The rarely used `use mod` statement no longer exists.
13390
13391 * Syntax extensions
13392 * `fail!` and `assert!` accept `~str`, `&'static str` or `fmt!`-style
13393 argument list.
13394 * `Encodable`, `Decodable`, `Ord`, `TotalOrd`, `TotalEq`, `DeepClone`,
13395 `Rand`, `Zero` and `ToStr` can all be automatically derived with
13396 `#[deriving(...)]`.
13397 * The `bytes!` macro returns a vector of bytes for string, u8, char,
13398 and unsuffixed integer literals.
13399
13400 * Libraries
13401 * The `core` crate was renamed to `std`.
13402 * The `std` crate was renamed to `extra`.
13403 * More and improved documentation.
13404 * std: `iterator` module for external iterator objects.
13405 * Many old-style (internal, higher-order function) iterators replaced by
13406 implementations of `Iterator`.
13407 * std: Many old internal vector and string iterators,
13408 incl. `any`, `all`. removed.
13409 * std: The `finalize` method of `Drop` renamed to `drop`.
13410 * std: The `drop` method now takes `&mut self` instead of `&self`.
13411 * std: The prelude no longer re-exports any modules, only types and traits.
13412 * std: Prelude additions: `print`, `println`, `FromStr`, `ApproxEq`, `Equiv`,
13413 `Iterator`, `IteratorUtil`, many numeric traits, many tuple traits.
13414 * std: New numeric traits: `Fractional`, `Real`, `RealExt`, `Integer`, `Ratio`,
13415 `Algebraic`, `Trigonometric`, `Exponential`, `Primitive`.
13416 * std: Tuple traits and accessors defined for up to 12-tuples, e.g.
13417 `(0, 1, 2).n2()` or `(0, 1, 2).n2_ref()`.
13418 * std: Many types implement `Clone`.
13419 * std: `path` type renamed to `Path`.
13420 * std: `mut` module and `Mut` type removed.
13421 * std: Many standalone functions removed in favor of methods and iterators
13422 in `vec`, `str`. In the future methods will also work as functions.
13423 * std: `reinterpret_cast` removed. Use `transmute`.
13424 * std: ascii string handling in `std::ascii`.
13425 * std: `Rand` is implemented for ~/@.
13426 * std: `run` module for spawning processes overhauled.
13427 * std: Various atomic types added to `unstable::atomic`.
13428 * std: Various types implement `Zero`.
13429 * std: `LinearMap` and `LinearSet` renamed to `HashMap` and `HashSet`.
13430 * std: Borrowed pointer functions moved from `ptr` to `borrow`.
13431 * std: Added `os::mkdir_recursive`.
13432 * std: Added `os::glob` function performs filesystems globs.
13433 * std: `FuzzyEq` renamed to `ApproxEq`.
13434 * std: `Map` now defines `pop` and `swap` methods.
13435 * std: `Cell` constructors converted to static methods.
13436 * extra: `rc` module adds the reference counted pointers, `Rc` and `RcMut`.
13437 * extra: `flate` module moved from `std` to `extra`.
13438 * extra: `fileinput` module for iterating over a series of files.
13439 * extra: `Complex` number type and `complex` module.
13440 * extra: `Rational` number type and `rational` module.
13441 * extra: `BigInt`, `BigUint` implement numeric and comparison traits.
13442 * extra: `term` uses terminfo now, is more correct.
13443 * extra: `arc` functions converted to methods.
13444 * extra: Implementation of fixed output size variations of SHA-2.
13445
13446 * Tooling
13447 * `unused_variables` lint mode for unused variables (default: warn).
13448 * `unused_unsafe` lint mode for detecting unnecessary `unsafe` blocks
13449 (default: warn).
13450 * `unused_mut` lint mode for identifying unused `mut` qualifiers
13451 (default: warn).
13452 * `dead_assignment` lint mode for unread variables (default: warn).
13453 * `unnecessary_allocation` lint mode detects some heap allocations that are
13454 immediately borrowed so could be written without allocating (default: warn).
13455 * `missing_doc` lint mode (default: allow).
13456 * `unreachable_code` lint mode (default: warn).
13457 * The `rusti` command has been rewritten and a number of bugs addressed.
13458 * rustc outputs in color on more terminals.
13459 * rustc accepts a `--link-args` flag to pass arguments to the linker.
13460 * rustc accepts a `-Z print-link-args` flag for debugging linkage.
13461 * Compiling with `-g` will make the binary record information about
13462 dynamic borrowcheck failures for debugging.
13463 * rustdoc has a nicer stylesheet.
13464 * Various improvements to rustdoc.
13465 * Improvements to rustpkg (see the detailed release notes).
13466
13467
13468Version 0.6 (2013-04-03)
13469========================
13470
13471 * ~2100 changes, numerous bugfixes
13472
13473 * Syntax changes
13474 * The self type parameter in traits is now spelled `Self`
13475 * The `self` parameter in trait and impl methods must now be explicitly
13476 named (for example: `fn f(&self) { }`). Implicit self is deprecated.
13477 * Static methods no longer require the `static` keyword and instead
13478 are distinguished by the lack of a `self` parameter
13479 * Replaced the `Durable` trait with the `'static` lifetime
13480 * The old closure type syntax with the trailing sigil has been
13481 removed in favor of the more consistent leading sigil
13482 * `super` is a keyword, and may be prefixed to paths
13483 * Trait bounds are separated with `+` instead of whitespace
13484 * Traits are implemented with `impl Trait for Type`
13485 instead of `impl Type: Trait`
13486 * Lifetime syntax is now `&'l foo` instead of `&l/foo`
13487 * The `export` keyword has finally been removed
13488 * The `move` keyword has been removed (see "Semantic changes")
13489 * The interior mutability qualifier on vectors, `[mut T]`, has been
13490 removed. Use `&mut [T]`, etc.
13491 * `mut` is no longer valid in `~mut T`. Use inherited mutability
13492 * `fail` is no longer a keyword. Use `fail!()`
13493 * `assert` is no longer a keyword. Use `assert!()`
13494 * `log` is no longer a keyword. use `debug!`, etc.
13495 * 1-tuples may be represented as `(T,)`
13496 * Struct fields may no longer be `mut`. Use inherited mutability,
13497 `@mut T`, `core::mut` or `core::cell`
13498 * `extern mod { ... }` is no longer valid syntax for foreign
13499 function modules. Use extern blocks: `extern { ... }`
13500 * Newtype enums removed. Use tuple-structs.
13501 * Trait implementations no longer support visibility modifiers
13502 * Pattern matching over vectors improved and expanded
13503 * `const` renamed to `static` to correspond to lifetime name,
13504 and make room for future `static mut` unsafe mutable globals.
13505 * Replaced `#[deriving_eq]` with `#[deriving(Eq)]`, etc.
13506 * `Clone` implementations can be automatically generated with
13507 `#[deriving(Clone)]`
13508 * Casts to traits must use a pointer sigil, e.g. `@foo as @Bar`
13509 instead of `foo as Bar`.
13510 * Fixed length vector types are now written as `[int, .. 3]`
13511 instead of `[int * 3]`.
13512 * Fixed length vector types can express the length as a constant
13513 expression. (ex: `[int, .. GL_BUFFER_SIZE - 2]`)
13514
13515 * Semantic changes
13516 * Types with owned pointers or custom destructors move by default,
13517 eliminating the `move` keyword
13518 * All foreign functions are considered unsafe
13519 * &mut is now unaliasable
13520 * Writes to borrowed @mut pointers are prevented dynamically
13521 * () has size 0
13522 * The name of the main function can be customized using #[main]
13523 * The default type of an inferred closure is &fn instead of @fn
13524 * `use` statements may no longer be "chained" - they cannot import
13525 identifiers imported by previous `use` statements
13526 * `use` statements are crate relative, importing from the "top"
13527 of the crate by default. Paths may be prefixed with `super::`
13528 or `self::` to change the search behavior.
13529 * Method visibility is inherited from the implementation declaration
13530 * Structural records have been removed
13531 * Many more types can be used in static items, including enums
13532 'static-lifetime pointers and vectors
13533 * Pattern matching over vectors improved and expanded
13534 * Typechecking of closure types has been overhauled to
13535 improve inference and eliminate unsoundness
13536 * Macros leave scope at the end of modules, unless that module is
13537 tagged with #[macro_escape]
13538
13539 * Libraries
13540 * Added big integers to `std::bigint`
13541 * Removed `core::oldcomm` module
13542 * Added pipe-based `core::comm` module
13543 * Numeric traits have been reorganized under `core::num`
13544 * `vec::slice` finally returns a slice
13545 * `debug!` and friends don't require a format string, e.g. `debug!(Foo)`
13546 * Containers reorganized around traits in `core::container`
13547 * `core::dvec` removed, `~[T]` is a drop-in replacement
13548 * `core::send_map` renamed to `core::hashmap`
13549 * `std::map` removed; replaced with `core::hashmap`
13550 * `std::treemap` reimplemented as an owned balanced tree
13551 * `std::deque` and `std::smallintmap` reimplemented as owned containers
13552 * `core::trie` added as a fast ordered map for integer keys
13553 * Set types added to `core::hashmap`, `core::trie` and `std::treemap`
13554 * `Ord` split into `Ord` and `TotalOrd`. `Ord` is still used to
13555 overload the comparison operators, whereas `TotalOrd` is used
13556 by certain container types
13557
13558 * Other
13559 * Replaced the 'cargo' package manager with 'rustpkg'
13560 * Added all-purpose 'rust' tool
13561 * `rustc --test` now supports benchmarks with the `#[bench]` attribute
13562 * rustc now *attempts* to offer spelling suggestions
13563 * Improved support for ARM and Android
13564 * Preliminary MIPS backend
13565 * Improved foreign function ABI implementation for x86, x86_64
13566 * Various memory usage improvements
13567 * Rust code may be embedded in foreign code under limited circumstances
13568 * Inline assembler supported by new asm!() syntax extension.
13569
13570
13571Version 0.5 (2012-12-21)
13572===========================
13573
13574 * ~900 changes, numerous bugfixes
13575
13576 * Syntax changes
13577 * Removed `<-` move operator
13578 * Completed the transition from the `#fmt` extension syntax to `fmt!`
13579 * Removed old fixed length vector syntax - `[T]/N`
13580 * New token-based quasi-quoters, `quote_tokens!`, `quote_expr!`, etc.
13581 * Macros may now expand to items and statements
13582 * `a.b()` is always parsed as a method call, never as a field projection
13583 * `Eq` and `IterBytes` implementations can be automatically generated
13584 with `#[deriving_eq]` and `#[deriving_iter_bytes]` respectively
13585 * Removed the special crate language for `.rc` files
13586 * Function arguments may consist of any irrefutable pattern
13587
13588 * Semantic changes
13589 * `&` and `~` pointers may point to objects
13590 * Tuple structs - `struct Foo(Bar, Baz)`. Will replace newtype enums.
13591 * Enum variants may be structs
13592 * Destructors can be added to all nominal types with the Drop trait
13593 * Structs and nullary enum variants may be constants
13594 * Values that cannot be implicitly copied are now automatically moved
13595 without writing `move` explicitly
13596 * `&T` may now be coerced to `*T`
13597 * Coercions happen in `let` statements as well as function calls
13598 * `use` statements now take crate-relative paths
13599 * The module and type namespaces have been merged so that static
13600 method names can be resolved under the trait in which they are
13601 declared
13602
13603 * Improved support for language features
13604 * Trait inheritance works in many scenarios
13605 * More support for explicit self arguments in methods - `self`, `&self`
13606 `@self`, and `~self` all generally work as expected
13607 * Static methods work in more situations
13608 * Experimental: Traits may declare default methods for the implementations
13609 to use
13610
13611 * Libraries
13612 * New condition handling system in `core::condition`
13613 * Timsort added to `std::sort`
13614 * New priority queue, `std::priority_queue`
13615 * Pipes for serializable types, `std::flatpipes'
13616 * Serialization overhauled to be trait-based
13617 * Expanded `getopts` definitions
13618 * Moved futures to `std`
13619 * More functions are pure now
13620 * `core::comm` renamed to `oldcomm`. Still deprecated
13621 * `rustdoc` and `cargo` are libraries now
13622
13623 * Misc
13624 * Added a preliminary REPL, `rusti`
13625 * License changed from MIT to dual MIT/APL2
13626
13627
13628Version 0.4 (2012-10-15)
13629==========================
13630
13631 * ~2000 changes, numerous bugfixes
13632
13633 * Syntax
13634 * All keywords are now strict and may not be used as identifiers anywhere
13635 * Keyword removal: 'again', 'import', 'check', 'new', 'owned', 'send',
13636 'of', 'with', 'to', 'class'.
13637 * Classes are replaced with simpler structs
13638 * Explicit method self types
13639 * `ret` became `return` and `alt` became `match`
13640 * `import` is now `use`; `use is now `extern mod`
13641 * `extern mod { ... }` is now `extern { ... }`
13642 * `use mod` is the recommended way to import modules
13643 * `pub` and `priv` replace deprecated export lists
13644 * The syntax of `match` pattern arms now uses fat arrow (=>)
13645 * `main` no longer accepts an args vector; use `os::args` instead
13646
13647 * Semantics
13648 * Trait implementations are now coherent, ala Haskell typeclasses
13649 * Trait methods may be static
13650 * Argument modes are deprecated
13651 * Borrowed pointers are much more mature and recommended for use
13652 * Strings and vectors in the static region are stored in constant memory
13653 * Typestate was removed
13654 * Resolution rewritten to be more reliable
13655 * Support for 'dual-mode' data structures (freezing and thawing)
13656
13657 * Libraries
13658 * Most binary operators can now be overloaded via the traits in
13659 `core::ops'
13660 * `std::net::url` for representing URLs
13661 * Sendable hash maps in `core::send_map`
13662 * `core::task' gained a (currently unsafe) task-local storage API
13663
13664 * Concurrency
13665 * An efficient new intertask communication primitive called the pipe,
13666 along with a number of higher-level channel types, in `core::pipes`
13667 * `std::arc`, an atomically reference counted, immutable, shared memory
13668 type
13669 * `std::sync`, various exotic synchronization tools based on arcs and pipes
13670 * Futures are now based on pipes and sendable
13671 * More robust linked task failure
13672 * Improved task builder API
13673
13674 * Other
13675 * Improved error reporting
13676 * Preliminary JIT support
13677 * Preliminary work on precise GC
13678 * Extensive architectural improvements to rustc
13679 * Begun a transition away from buggy C++-based reflection (shape) code to
13680 Rust-based (visitor) code
13681 * All hash functions and tables converted to secure, randomized SipHash
13682
13683
13684Version 0.3 (2012-07-12)
13685========================
13686
13687 * ~1900 changes, numerous bugfixes
13688
13689 * New coding conveniences
13690 * Integer-literal suffix inference
13691 * Per-item control over warnings, errors
13692 * #[cfg(windows)] and #[cfg(unix)] attributes
13693 * Documentation comments
13694 * More compact closure syntax
13695 * 'do' expressions for treating higher-order functions as
13696 control structures
13697 * *-patterns (wildcard extended to all constructor fields)
13698
13699 * Semantic cleanup
13700 * Name resolution pass and exhaustiveness checker rewritten
13701 * Region pointers and borrow checking supersede alias
13702 analysis
13703 * Init-ness checking is now provided by a region-based liveness
13704 pass instead of the typestate pass; same for last-use analysis
13705 * Extensive work on region pointers
13706
13707 * Experimental new language features
13708 * Slices and fixed-size, interior-allocated vectors
13709 * #!-comments for lang versioning, shell execution
13710 * Destructors and iface implementation for classes;
13711 type-parameterized classes and class methods
13712 * 'const' type kind for types that can be used to implement
13713 shared-memory concurrency patterns
13714
13715 * Type reflection
13716
13717 * Removal of various obsolete features
13718 * Keywords: 'be', 'prove', 'syntax', 'note', 'mutable', 'bind',
13719 'crust', 'native' (now 'extern'), 'cont' (now 'again')
13720
13721 * Constructs: do-while loops ('do' repurposed), fn binding,
13722 resources (replaced by destructors)
13723
13724 * Compiler reorganization
13725 * Syntax-layer of compiler split into separate crate
13726 * Clang (from LLVM project) integrated into build
13727 * Typechecker split into sub-modules
13728
13729 * New library code
13730 * New time functions
13731 * Extension methods for many built-in types
13732 * Arc: atomic-refcount read-only / exclusive-use shared cells
13733 * Par: parallel map and search routines
13734 * Extensive work on libuv interface
13735 * Much vector code moved to libraries
13736 * Syntax extensions: #line, #col, #file, #mod, #stringify,
13737 #include, #include_str, #include_bin
13738
13739 * Tool improvements
13740 * Cargo automatically resolves dependencies
13741
13742
13743Version 0.2 (2012-03-29)
13744=========================
13745
13746 * >1500 changes, numerous bugfixes
13747
13748 * New docs and doc tooling
13749
13750 * New port: FreeBSD x86_64
13751
13752 * Compilation model enhancements
13753 * Generics now specialized, multiply instantiated
13754 * Functions now inlined across separate crates
13755
13756 * Scheduling, stack and threading fixes
13757 * Noticeably improved message-passing performance
13758 * Explicit schedulers
13759 * Callbacks from C
13760 * Helgrind clean
13761
13762 * Experimental new language features
13763 * Operator overloading
13764 * Region pointers
13765 * Classes
13766
13767 * Various language extensions
13768 * C-callback function types: 'crust fn ...'
13769 * Infinite-loop construct: 'loop { ... }'
13770 * Shorten 'mutable' to 'mut'
13771 * Required mutable-local qualifier: 'let mut ...'
13772 * Basic glob-exporting: 'export foo::*;'
13773 * Alt now exhaustive, 'alt check' for runtime-checked
13774 * Block-function form of 'for' loop, with 'break' and 'ret'.
13775
13776 * New library code
13777 * AST quasi-quote syntax extension
13778 * Revived libuv interface
13779 * New modules: core::{future, iter}, std::arena
13780 * Merged per-platform std::{os*, fs*} to core::{libc, os}
13781 * Extensive cleanup, regularization in libstd, libcore
13782
13783
13784Version 0.1 (2012-01-20)
13785===============================
13786
13787 * Most language features work, including:
13788 * Unique pointers, unique closures, move semantics
13789 * Interface-constrained generics
13790 * Static interface dispatch
13791 * Stack growth
13792 * Multithread task scheduling
13793 * Typestate predicates
13794 * Failure unwinding, destructors
13795 * Pattern matching and destructuring assignment
13796 * Lightweight block-lambda syntax
13797 * Preliminary macro-by-example
13798
13799 * Compiler works with the following configurations:
13800 * Linux: x86 and x86_64 hosts and targets
13801 * macOS: x86 and x86_64 hosts and targets
13802 * Windows: x86 hosts and targets
13803
13804 * Cross compilation / multi-target configuration supported.
13805
13806 * Preliminary API-documentation and package-management tools included.
13807
13808Known issues:
13809
13810 * Documentation is incomplete.
13811
13812 * Performance is below intended target.
13813
13814 * Standard library APIs are subject to extensive change, reorganization.
13815
13816 * Language-level versioning is not yet operational - future code will
13817 break unexpectedly.
backport for Debian buster