1 use crate::cgu_reuse_tracker
::CguReuseTracker
;
2 use crate::code_stats
::CodeStats
;
3 pub use crate::code_stats
::{DataTypeKind, FieldInfo, SizeKind, VariantInfo}
;
4 use crate::config
::{self, CrateType, OutputType, SwitchWithOptPath}
;
5 use crate::parse
::ParseSess
;
6 use crate::search_paths
::{PathKind, SearchPath}
;
7 use crate::{filesearch, lint}
;
9 pub use rustc_ast
::attr
::MarkedAttrs
;
10 pub use rustc_ast
::Attribute
;
11 use rustc_data_structures
::flock
;
12 use rustc_data_structures
::fx
::{FxHashMap, FxHashSet}
;
13 use rustc_data_structures
::jobserver
::{self, Client}
;
14 use rustc_data_structures
::profiling
::{duration_to_secs_str, SelfProfiler, SelfProfilerRef}
;
15 use rustc_data_structures
::sync
::{
16 self, AtomicU64
, AtomicUsize
, Lock
, Lrc
, OnceCell
, OneThread
, Ordering
, Ordering
::SeqCst
,
18 use rustc_errors
::annotate_snippet_emitter_writer
::AnnotateSnippetEmitterWriter
;
19 use rustc_errors
::emitter
::{Emitter, EmitterWriter, HumanReadableErrorType}
;
20 use rustc_errors
::json
::JsonEmitter
;
21 use rustc_errors
::registry
::Registry
;
22 use rustc_errors
::{DiagnosticBuilder, DiagnosticId, ErrorReported}
;
23 use rustc_macros
::HashStable_Generic
;
24 pub use rustc_span
::def_id
::StableCrateId
;
25 use rustc_span
::edition
::Edition
;
26 use rustc_span
::source_map
::{FileLoader, MultiSpan, RealFileLoader, SourceMap, Span}
;
27 use rustc_span
::{sym, SourceFileHashAlgorithm, Symbol}
;
28 use rustc_target
::asm
::InlineAsmArch
;
29 use rustc_target
::spec
::{CodeModel, PanicStrategy, RelocModel, RelroLevel}
;
30 use rustc_target
::spec
::{
31 SanitizerSet
, SplitDebuginfo
, StackProtector
, Target
, TargetTriple
, TlsModel
,
34 use std
::cell
::{self, RefCell}
;
38 use std
::num
::NonZeroU32
;
39 use std
::ops
::{Div, Mul}
;
40 use std
::path
::{Path, PathBuf}
;
41 use std
::str::FromStr
;
43 use std
::time
::Duration
;
45 pub struct OptimizationFuel
{
46 /// If `-zfuel=crate=n` is specified, initially set to `n`, otherwise `0`.
48 /// We're rejecting all further optimizations.
52 /// The behavior of the CTFE engine when an error occurs with regards to backtraces.
53 #[derive(Clone, Copy)]
54 pub enum CtfeBacktrace
{
55 /// Do nothing special, return the error as usual without a backtrace.
57 /// Capture a backtrace at the point the error is created and return it in the error
58 /// (to be printed later if/when the error ever actually gets shown to the user).
60 /// Capture a backtrace at the point the error is created and immediately print it out.
64 /// New-type wrapper around `usize` for representing limits. Ensures that comparisons against
65 /// limits are consistent throughout the compiler.
66 #[derive(Clone, Copy, Debug, HashStable_Generic)]
67 pub struct Limit(pub usize);
70 /// Create a new limit from a `usize`.
71 pub fn new(value
: usize) -> Self {
75 /// Check that `value` is within the limit. Ensures that the same comparisons are used
76 /// throughout the compiler, as mismatches can cause ICEs, see #72540.
78 pub fn value_within_limit(&self, value
: usize) -> bool
{
83 impl From
<usize> for Limit
{
84 fn from(value
: usize) -> Self {
89 impl fmt
::Display
for Limit
{
90 fn fmt(&self, f
: &mut fmt
::Formatter
<'_
>) -> fmt
::Result
{
91 write
!(f
, "{}", self.0)
95 impl Div
<usize> for Limit
{
98 fn div(self, rhs
: usize) -> Self::Output
{
99 Limit
::new(self.0 / rhs
)
103 impl Mul
<usize> for Limit
{
106 fn mul(self, rhs
: usize) -> Self::Output
{
107 Limit
::new(self.0 * rhs
)
111 #[derive(Clone, Copy, Debug, HashStable_Generic)]
113 /// The maximum recursion limit for potentially infinitely recursive
114 /// operations such as auto-dereference and monomorphization.
115 pub recursion_limit
: Limit
,
116 /// The size at which the `large_assignments` lint starts
118 pub move_size_limit
: Limit
,
119 /// The maximum length of types during monomorphization.
120 pub type_length_limit
: Limit
,
121 /// The maximum blocks a const expression can evaluate.
122 pub const_eval_limit
: Limit
,
125 /// Represents the data associated with a compilation
126 /// session for a single crate.
130 pub opts
: config
::Options
,
131 pub host_tlib_path
: Lrc
<SearchPath
>,
132 pub target_tlib_path
: Lrc
<SearchPath
>,
133 pub parse_sess
: ParseSess
,
134 pub sysroot
: PathBuf
,
135 /// The name of the root source file of the crate, in the local file system.
136 /// `None` means that there is no source file.
137 pub local_crate_source_file
: Option
<PathBuf
>,
139 /// Set of `(DiagnosticId, Option<Span>, message)` tuples tracking
140 /// (sub)diagnostics that have been set once, but should not be set again,
141 /// in order to avoid redundantly verbose output (Issue #24690, #44953).
142 pub one_time_diagnostics
: Lock
<FxHashSet
<(DiagnosticMessageId
, Option
<Span
>, String
)>>,
143 crate_types
: OnceCell
<Vec
<CrateType
>>,
144 /// The `stable_crate_id` is constructed out of the crate name and all the
145 /// `-C metadata` arguments passed to the compiler. Its value forms a unique
146 /// global identifier for the crate. It is used to allow multiple crates
147 /// with the same name to coexist. See the
148 /// `rustc_codegen_llvm::back::symbol_names` module for more information.
149 pub stable_crate_id
: OnceCell
<StableCrateId
>,
151 features
: OnceCell
<rustc_feature
::Features
>,
153 incr_comp_session
: OneThread
<RefCell
<IncrCompSession
>>,
154 /// Used for incremental compilation tests. Will only be populated if
155 /// `-Zquery-dep-graph` is specified.
156 pub cgu_reuse_tracker
: CguReuseTracker
,
158 /// Used by `-Z self-profile`.
159 pub prof
: SelfProfilerRef
,
161 /// Some measurements that are being gathered during compilation.
162 pub perf_stats
: PerfStats
,
164 /// Data about code being compiled, gathered during compilation.
165 pub code_stats
: CodeStats
,
167 /// Tracks fuel info if `-zfuel=crate=n` is specified.
168 optimization_fuel
: Lock
<OptimizationFuel
>,
170 /// Always set to zero and incremented so that we can print fuel expended by a crate.
171 pub print_fuel
: AtomicU64
,
173 /// Loaded up early on in the initialization of this `Session` to avoid
174 /// false positives about a job server in our environment.
175 pub jobserver
: Client
,
177 /// Cap lint level specified by a driver specifically.
178 pub driver_lint_caps
: FxHashMap
<lint
::LintId
, lint
::Level
>,
180 /// Tracks the current behavior of the CTFE engine when an error occurs.
181 /// Options range from returning the error without a backtrace to returning an error
182 /// and immediately printing the backtrace to stderr.
183 /// The `Lock` is only used by miri to allow setting `ctfe_backtrace` after analysis when
184 /// `MIRI_BACKTRACE` is set. This makes it only apply to miri's errors and not to all CTFE
186 pub ctfe_backtrace
: Lock
<CtfeBacktrace
>,
188 /// This tracks where `-Zunleash-the-miri-inside-of-you` was used to get around a
189 /// const check, optionally with the relevant feature gate. We use this to
190 /// warn about unleashing, but with a single diagnostic instead of dozens that
191 /// drown everything else in noise.
192 miri_unleashed_features
: Lock
<Vec
<(Span
, Option
<Symbol
>)>>,
194 /// Architecture to use for interpreting asm!.
195 pub asm_arch
: Option
<InlineAsmArch
>,
197 /// Set of enabled features for the current target.
198 pub target_features
: FxHashSet
<Symbol
>,
201 pub struct PerfStats
{
202 /// The accumulated time spent on computing symbol hashes.
203 pub symbol_hash_time
: Lock
<Duration
>,
204 /// Total number of values canonicalized queries constructed.
205 pub queries_canonicalized
: AtomicUsize
,
206 /// Number of times this query is invoked.
207 pub normalize_generic_arg_after_erasing_regions
: AtomicUsize
,
208 /// Number of times this query is invoked.
209 pub normalize_projection_ty
: AtomicUsize
,
212 /// Enum to support dispatch of one-time diagnostics (in `Session.diag_once`).
213 enum DiagnosticBuilderMethod
{
216 // Add more variants as needed to support one-time diagnostics.
219 /// Trait implemented by error types. This should not be implemented manually. Instead, use
220 /// `#[derive(SessionDiagnostic)]` -- see [rustc_macros::SessionDiagnostic].
221 pub trait SessionDiagnostic
<'a
> {
222 /// Write out as a diagnostic out of `sess`.
224 fn into_diagnostic(self, sess
: &'a Session
) -> DiagnosticBuilder
<'a
>;
227 /// Diagnostic message ID, used by `Session.one_time_diagnostics` to avoid
228 /// emitting the same message more than once.
229 #[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
230 pub enum DiagnosticMessageId
{
231 ErrorId(u16), // EXXXX error code as integer
232 LintId(lint
::LintId
),
233 StabilityId(Option
<NonZeroU32
>), // issue number
236 impl From
<&'
static lint
::Lint
> for DiagnosticMessageId
{
237 fn from(lint
: &'
static lint
::Lint
) -> Self {
238 DiagnosticMessageId
::LintId(lint
::LintId
::of(lint
))
243 pub fn miri_unleashed_feature(&self, span
: Span
, feature_gate
: Option
<Symbol
>) {
244 self.miri_unleashed_features
.lock().push((span
, feature_gate
));
247 fn check_miri_unleashed_features(&self) {
248 let unleashed_features
= self.miri_unleashed_features
.lock();
249 if !unleashed_features
.is_empty() {
250 let mut must_err
= false;
251 // Create a diagnostic pointing at where things got unleashed.
252 let mut diag
= self.struct_warn("skipping const checks");
253 for &(span
, feature_gate
) in unleashed_features
.iter() {
254 // FIXME: `span_label` doesn't do anything, so we use "help" as a hack.
255 if let Some(feature_gate
) = feature_gate
{
256 diag
.span_help(span
, &format
!("skipping check for `{}` feature", feature_gate
));
257 // The unleash flag must *not* be used to just "hack around" feature gates.
260 diag
.span_help(span
, "skipping check that does not even have a feature gate");
264 // If we should err, make sure we did.
265 if must_err
&& !self.has_errors() {
266 // We have skipped a feature gate, and not run into other errors... reject.
268 "`-Zunleash-the-miri-inside-of-you` may not be used to circumvent feature \
269 gates, except when testing error paths in the CTFE engine",
275 /// Invoked all the way at the end to finish off diagnostics printing.
276 pub fn finish_diagnostics(&self, registry
: &Registry
) {
277 self.check_miri_unleashed_features();
278 self.diagnostic().print_error_count(registry
);
279 self.emit_future_breakage();
282 fn emit_future_breakage(&self) {
283 if !self.opts
.json_future_incompat
{
287 let diags
= self.diagnostic().take_future_breakage_diagnostics();
288 if diags
.is_empty() {
291 self.parse_sess
.span_diagnostic
.emit_future_breakage_report(diags
);
294 pub fn local_stable_crate_id(&self) -> StableCrateId
{
295 self.stable_crate_id
.get().copied().unwrap()
298 pub fn crate_types(&self) -> &[CrateType
] {
299 self.crate_types
.get().unwrap().as_slice()
302 pub fn init_crate_types(&self, crate_types
: Vec
<CrateType
>) {
303 self.crate_types
.set(crate_types
).expect("`crate_types` was initialized twice")
306 pub fn struct_span_warn
<S
: Into
<MultiSpan
>>(&self, sp
: S
, msg
: &str) -> DiagnosticBuilder
<'_
> {
307 self.diagnostic().struct_span_warn(sp
, msg
)
309 pub fn struct_span_force_warn
<S
: Into
<MultiSpan
>>(
313 ) -> DiagnosticBuilder
<'_
> {
314 self.diagnostic().struct_span_force_warn(sp
, msg
)
316 pub fn struct_span_warn_with_code
<S
: Into
<MultiSpan
>>(
321 ) -> DiagnosticBuilder
<'_
> {
322 self.diagnostic().struct_span_warn_with_code(sp
, msg
, code
)
324 pub fn struct_warn(&self, msg
: &str) -> DiagnosticBuilder
<'_
> {
325 self.diagnostic().struct_warn(msg
)
327 pub fn struct_force_warn(&self, msg
: &str) -> DiagnosticBuilder
<'_
> {
328 self.diagnostic().struct_force_warn(msg
)
330 pub fn struct_span_allow
<S
: Into
<MultiSpan
>>(&self, sp
: S
, msg
: &str) -> DiagnosticBuilder
<'_
> {
331 self.diagnostic().struct_span_allow(sp
, msg
)
333 pub fn struct_allow(&self, msg
: &str) -> DiagnosticBuilder
<'_
> {
334 self.diagnostic().struct_allow(msg
)
336 pub fn struct_span_err
<S
: Into
<MultiSpan
>>(&self, sp
: S
, msg
: &str) -> DiagnosticBuilder
<'_
> {
337 self.diagnostic().struct_span_err(sp
, msg
)
339 pub fn struct_span_err_with_code
<S
: Into
<MultiSpan
>>(
344 ) -> DiagnosticBuilder
<'_
> {
345 self.diagnostic().struct_span_err_with_code(sp
, msg
, code
)
347 // FIXME: This method should be removed (every error should have an associated error code).
348 pub fn struct_err(&self, msg
: &str) -> DiagnosticBuilder
<'_
> {
349 self.diagnostic().struct_err(msg
)
351 pub fn struct_err_with_code(&self, msg
: &str, code
: DiagnosticId
) -> DiagnosticBuilder
<'_
> {
352 self.diagnostic().struct_err_with_code(msg
, code
)
354 pub fn struct_span_fatal
<S
: Into
<MultiSpan
>>(&self, sp
: S
, msg
: &str) -> DiagnosticBuilder
<'_
> {
355 self.diagnostic().struct_span_fatal(sp
, msg
)
357 pub fn struct_span_fatal_with_code
<S
: Into
<MultiSpan
>>(
362 ) -> DiagnosticBuilder
<'_
> {
363 self.diagnostic().struct_span_fatal_with_code(sp
, msg
, code
)
365 pub fn struct_fatal(&self, msg
: &str) -> DiagnosticBuilder
<'_
> {
366 self.diagnostic().struct_fatal(msg
)
369 pub fn span_fatal
<S
: Into
<MultiSpan
>>(&self, sp
: S
, msg
: &str) -> ! {
370 self.diagnostic().span_fatal(sp
, msg
)
372 pub fn span_fatal_with_code
<S
: Into
<MultiSpan
>>(
378 self.diagnostic().span_fatal_with_code(sp
, msg
, code
)
380 pub fn fatal(&self, msg
: &str) -> ! {
381 self.diagnostic().fatal(msg
).raise()
383 pub fn span_err_or_warn
<S
: Into
<MultiSpan
>>(&self, is_warning
: bool
, sp
: S
, msg
: &str) {
385 self.span_warn(sp
, msg
);
387 self.span_err(sp
, msg
);
390 pub fn span_err
<S
: Into
<MultiSpan
>>(&self, sp
: S
, msg
: &str) {
391 self.diagnostic().span_err(sp
, msg
)
393 pub fn span_err_with_code
<S
: Into
<MultiSpan
>>(&self, sp
: S
, msg
: &str, code
: DiagnosticId
) {
394 self.diagnostic().span_err_with_code(sp
, &msg
, code
)
396 pub fn err(&self, msg
: &str) {
397 self.diagnostic().err(msg
)
399 pub fn emit_err
<'a
>(&'a
self, err
: impl SessionDiagnostic
<'a
>) {
400 err
.into_diagnostic(self).emit()
403 pub fn err_count(&self) -> usize {
404 self.diagnostic().err_count()
406 pub fn has_errors(&self) -> bool
{
407 self.diagnostic().has_errors()
409 pub fn has_errors_or_delayed_span_bugs(&self) -> bool
{
410 self.diagnostic().has_errors_or_delayed_span_bugs()
412 pub fn abort_if_errors(&self) {
413 self.diagnostic().abort_if_errors();
415 pub fn compile_status(&self) -> Result
<(), ErrorReported
> {
416 if self.diagnostic().has_errors_or_lint_errors() {
417 self.diagnostic().emit_stashed_diagnostics();
423 // FIXME(matthewjasper) Remove this method, it should never be needed.
424 pub fn track_errors
<F
, T
>(&self, f
: F
) -> Result
<T
, ErrorReported
>
428 let old_count
= self.err_count();
430 if self.err_count() == old_count { Ok(result) }
else { Err(ErrorReported) }
432 pub fn span_warn
<S
: Into
<MultiSpan
>>(&self, sp
: S
, msg
: &str) {
433 self.diagnostic().span_warn(sp
, msg
)
435 pub fn span_warn_with_code
<S
: Into
<MultiSpan
>>(&self, sp
: S
, msg
: &str, code
: DiagnosticId
) {
436 self.diagnostic().span_warn_with_code(sp
, msg
, code
)
438 pub fn warn(&self, msg
: &str) {
439 self.diagnostic().warn(msg
)
441 /// Delay a span_bug() call until abort_if_errors()
443 pub fn delay_span_bug
<S
: Into
<MultiSpan
>>(&self, sp
: S
, msg
: &str) {
444 self.diagnostic().delay_span_bug(sp
, msg
)
447 /// Used for code paths of expensive computations that should only take place when
448 /// warnings or errors are emitted. If no messages are emitted ("good path"), then
449 /// it's likely a bug.
450 pub fn delay_good_path_bug(&self, msg
: &str) {
451 if self.opts
.debugging_opts
.print_type_sizes
452 || self.opts
.debugging_opts
.query_dep_graph
453 || self.opts
.debugging_opts
.dump_mir
.is_some()
454 || self.opts
.debugging_opts
.unpretty
.is_some()
455 || self.opts
.output_types
.contains_key(&OutputType
::Mir
)
456 || std
::env
::var_os("RUSTC_LOG").is_some()
461 self.diagnostic().delay_good_path_bug(msg
)
464 pub fn note_without_error(&self, msg
: &str) {
465 self.diagnostic().note_without_error(msg
)
467 pub fn span_note_without_error
<S
: Into
<MultiSpan
>>(&self, sp
: S
, msg
: &str) {
468 self.diagnostic().span_note_without_error(sp
, msg
)
470 pub fn struct_note_without_error(&self, msg
: &str) -> DiagnosticBuilder
<'_
> {
471 self.diagnostic().struct_note_without_error(msg
)
475 pub fn diagnostic(&self) -> &rustc_errors
::Handler
{
476 &self.parse_sess
.span_diagnostic
479 pub fn with_disabled_diagnostic
<T
, F
: FnOnce() -> T
>(&self, f
: F
) -> T
{
480 self.parse_sess
.span_diagnostic
.with_disabled_diagnostic(f
)
483 /// Analogous to calling methods on the given `DiagnosticBuilder`, but
484 /// deduplicates on lint ID, span (if any), and message for this `Session`
485 fn diag_once
<'a
, 'b
>(
487 diag_builder
: &'b
mut DiagnosticBuilder
<'a
>,
488 method
: DiagnosticBuilderMethod
,
489 msg_id
: DiagnosticMessageId
,
491 span_maybe
: Option
<Span
>,
493 let id_span_message
= (msg_id
, span_maybe
, message
.to_owned());
494 let fresh
= self.one_time_diagnostics
.borrow_mut().insert(id_span_message
);
497 DiagnosticBuilderMethod
::Note
=> {
498 diag_builder
.note(message
);
500 DiagnosticBuilderMethod
::SpanNote
=> {
501 let span
= span_maybe
.expect("`span_note` needs a span");
502 diag_builder
.span_note(span
, message
);
508 pub fn diag_span_note_once
<'a
, 'b
>(
510 diag_builder
: &'b
mut DiagnosticBuilder
<'a
>,
511 msg_id
: DiagnosticMessageId
,
517 DiagnosticBuilderMethod
::SpanNote
,
524 pub fn diag_note_once
<'a
, 'b
>(
526 diag_builder
: &'b
mut DiagnosticBuilder
<'a
>,
527 msg_id
: DiagnosticMessageId
,
530 self.diag_once(diag_builder
, DiagnosticBuilderMethod
::Note
, msg_id
, message
, None
);
534 pub fn source_map(&self) -> &SourceMap
{
535 self.parse_sess
.source_map()
537 pub fn verbose(&self) -> bool
{
538 self.opts
.debugging_opts
.verbose
540 pub fn time_passes(&self) -> bool
{
541 self.opts
.debugging_opts
.time_passes
|| self.opts
.debugging_opts
.time
543 pub fn instrument_mcount(&self) -> bool
{
544 self.opts
.debugging_opts
.instrument_mcount
546 pub fn time_llvm_passes(&self) -> bool
{
547 self.opts
.debugging_opts
.time_llvm_passes
549 pub fn meta_stats(&self) -> bool
{
550 self.opts
.debugging_opts
.meta_stats
552 pub fn asm_comments(&self) -> bool
{
553 self.opts
.debugging_opts
.asm_comments
555 pub fn verify_llvm_ir(&self) -> bool
{
556 self.opts
.debugging_opts
.verify_llvm_ir
|| option_env
!("RUSTC_VERIFY_LLVM_IR").is_some()
558 pub fn print_llvm_passes(&self) -> bool
{
559 self.opts
.debugging_opts
.print_llvm_passes
561 pub fn binary_dep_depinfo(&self) -> bool
{
562 self.opts
.debugging_opts
.binary_dep_depinfo
564 pub fn mir_opt_level(&self) -> usize {
565 self.opts
.mir_opt_level()
568 /// Gets the features enabled for the current compilation session.
569 /// DO NOT USE THIS METHOD if there is a TyCtxt available, as it circumvents
570 /// dependency tracking. Use tcx.features() instead.
572 pub fn features_untracked(&self) -> &rustc_feature
::Features
{
573 self.features
.get().unwrap()
576 pub fn init_features(&self, features
: rustc_feature
::Features
) {
577 match self.features
.set(features
) {
579 Err(_
) => panic
!("`features` was initialized twice"),
583 /// Calculates the flavor of LTO to use for this compilation.
584 pub fn lto(&self) -> config
::Lto
{
585 // If our target has codegen requirements ignore the command line
586 if self.target
.requires_lto
{
587 return config
::Lto
::Fat
;
590 // If the user specified something, return that. If they only said `-C
591 // lto` and we've for whatever reason forced off ThinLTO via the CLI,
592 // then ensure we can't use a ThinLTO.
593 match self.opts
.cg
.lto
{
594 config
::LtoCli
::Unspecified
=> {
595 // The compiler was invoked without the `-Clto` flag. Fall
596 // through to the default handling
598 config
::LtoCli
::No
=> {
599 // The user explicitly opted out of any kind of LTO
600 return config
::Lto
::No
;
602 config
::LtoCli
::Yes
| config
::LtoCli
::Fat
| config
::LtoCli
::NoParam
=> {
603 // All of these mean fat LTO
604 return config
::Lto
::Fat
;
606 config
::LtoCli
::Thin
=> {
607 return if self.opts
.cli_forced_thinlto_off
{
615 // Ok at this point the target doesn't require anything and the user
616 // hasn't asked for anything. Our next decision is whether or not
617 // we enable "auto" ThinLTO where we use multiple codegen units and
618 // then do ThinLTO over those codegen units. The logic below will
619 // either return `No` or `ThinLocal`.
621 // If processing command line options determined that we're incompatible
622 // with ThinLTO (e.g., `-C lto --emit llvm-ir`) then return that option.
623 if self.opts
.cli_forced_thinlto_off
{
624 return config
::Lto
::No
;
627 // If `-Z thinlto` specified process that, but note that this is mostly
628 // a deprecated option now that `-C lto=thin` exists.
629 if let Some(enabled
) = self.opts
.debugging_opts
.thinlto
{
631 return config
::Lto
::ThinLocal
;
633 return config
::Lto
::No
;
637 // If there's only one codegen unit and LTO isn't enabled then there's
638 // no need for ThinLTO so just return false.
639 if self.codegen_units() == 1 {
640 return config
::Lto
::No
;
643 // Now we're in "defaults" territory. By default we enable ThinLTO for
644 // optimized compiles (anything greater than O0).
645 match self.opts
.optimize
{
646 config
::OptLevel
::No
=> config
::Lto
::No
,
647 _
=> config
::Lto
::ThinLocal
,
651 /// Returns the panic strategy for this compile session. If the user explicitly selected one
652 /// using '-C panic', use that, otherwise use the panic strategy defined by the target.
653 pub fn panic_strategy(&self) -> PanicStrategy
{
654 self.opts
.cg
.panic
.unwrap_or(self.target
.panic_strategy
)
656 pub fn fewer_names(&self) -> bool
{
657 if let Some(fewer_names
) = self.opts
.debugging_opts
.fewer_names
{
660 let more_names
= self.opts
.output_types
.contains_key(&OutputType
::LlvmAssembly
)
661 || self.opts
.output_types
.contains_key(&OutputType
::Bitcode
)
662 // AddressSanitizer and MemorySanitizer use alloca name when reporting an issue.
663 || self.opts
.debugging_opts
.sanitizer
.intersects(SanitizerSet
::ADDRESS
| SanitizerSet
::MEMORY
);
668 pub fn unstable_options(&self) -> bool
{
669 self.opts
.debugging_opts
.unstable_options
671 pub fn is_nightly_build(&self) -> bool
{
672 self.opts
.unstable_features
.is_nightly_build()
674 pub fn is_sanitizer_cfi_enabled(&self) -> bool
{
675 self.opts
.debugging_opts
.sanitizer
.contains(SanitizerSet
::CFI
)
677 pub fn overflow_checks(&self) -> bool
{
678 self.opts
.cg
.overflow_checks
.unwrap_or(self.opts
.debug_assertions
)
681 /// Check whether this compile session and crate type use static crt.
682 pub fn crt_static(&self, crate_type
: Option
<CrateType
>) -> bool
{
683 if !self.target
.crt_static_respected
{
684 // If the target does not opt in to crt-static support, use its default.
685 return self.target
.crt_static_default
;
688 let requested_features
= self.opts
.cg
.target_feature
.split('
,'
);
689 let found_negative
= requested_features
.clone().any(|r
| r
== "-crt-static");
690 let found_positive
= requested_features
.clone().any(|r
| r
== "+crt-static");
692 if found_positive
|| found_negative
{
694 } else if crate_type
== Some(CrateType
::ProcMacro
)
695 || crate_type
== None
&& self.opts
.crate_types
.contains(&CrateType
::ProcMacro
)
697 // FIXME: When crate_type is not available,
698 // we use compiler options to determine the crate_type.
699 // We can't check `#![crate_type = "proc-macro"]` here.
702 self.target
.crt_static_default
706 pub fn relocation_model(&self) -> RelocModel
{
707 self.opts
.cg
.relocation_model
.unwrap_or(self.target
.relocation_model
)
710 pub fn code_model(&self) -> Option
<CodeModel
> {
711 self.opts
.cg
.code_model
.or(self.target
.code_model
)
714 pub fn tls_model(&self) -> TlsModel
{
715 self.opts
.debugging_opts
.tls_model
.unwrap_or(self.target
.tls_model
)
718 pub fn is_wasi_reactor(&self) -> bool
{
719 self.target
.options
.os
== "wasi"
721 self.opts
.debugging_opts
.wasi_exec_model
,
722 Some(config
::WasiExecModel
::Reactor
)
726 pub fn split_debuginfo(&self) -> SplitDebuginfo
{
727 self.opts
.cg
.split_debuginfo
.unwrap_or(self.target
.split_debuginfo
)
730 pub fn stack_protector(&self) -> StackProtector
{
731 if self.target
.options
.supports_stack_protector
{
732 self.opts
.debugging_opts
.stack_protector
738 pub fn target_can_use_split_dwarf(&self) -> bool
{
739 !self.target
.is_like_windows
&& !self.target
.is_like_osx
742 pub fn must_emit_unwind_tables(&self) -> bool
{
743 // This is used to control the emission of the `uwtable` attribute on
746 // Unwind tables are needed when compiling with `-C panic=unwind`, but
747 // LLVM won't omit unwind tables unless the function is also marked as
748 // `nounwind`, so users are allowed to disable `uwtable` emission.
749 // Historically rustc always emits `uwtable` attributes by default, so
750 // even they can be disabled, they're still emitted by default.
752 // On some targets (including windows), however, exceptions include
753 // other events such as illegal instructions, segfaults, etc. This means
754 // that on Windows we end up still needing unwind tables even if the `-C
755 // panic=abort` flag is passed.
757 // You can also find more info on why Windows needs unwind tables in:
758 // https://bugzilla.mozilla.org/show_bug.cgi?id=1302078
760 // If a target requires unwind tables, then they must be emitted.
761 // Otherwise, we can defer to the `-C force-unwind-tables=<yes/no>`
762 // value, if it is provided, or disable them, if not.
763 self.target
.requires_uwtable
764 || self.opts
.cg
.force_unwind_tables
.unwrap_or(
765 self.panic_strategy() == PanicStrategy
::Unwind
|| self.target
.default_uwtable
,
769 pub fn generate_proc_macro_decls_symbol(&self, stable_crate_id
: StableCrateId
) -> String
{
770 format
!("__rustc_proc_macro_decls_{:08x}__", stable_crate_id
.to_u64())
773 pub fn target_filesearch(&self, kind
: PathKind
) -> filesearch
::FileSearch
<'_
> {
774 filesearch
::FileSearch
::new(
776 self.opts
.target_triple
.triple(),
777 &self.opts
.search_paths
,
778 &self.target_tlib_path
,
782 pub fn host_filesearch(&self, kind
: PathKind
) -> filesearch
::FileSearch
<'_
> {
783 filesearch
::FileSearch
::new(
785 config
::host_triple(),
786 &self.opts
.search_paths
,
787 &self.host_tlib_path
,
792 /// Returns a list of directories where target-specific tool binaries are located.
793 pub fn get_tools_search_paths(&self, self_contained
: bool
) -> Vec
<PathBuf
> {
794 let rustlib_path
= rustc_target
::target_rustlib_path(&self.sysroot
, &config
::host_triple());
795 let p
= PathBuf
::from_iter([
796 Path
::new(&self.sysroot
),
797 Path
::new(&rustlib_path
),
800 if self_contained { vec![p.clone(), p.join("self-contained")] }
else { vec![p] }
803 pub fn init_incr_comp_session(
805 session_dir
: PathBuf
,
806 lock_file
: flock
::Lock
,
807 load_dep_graph
: bool
,
809 let mut incr_comp_session
= self.incr_comp_session
.borrow_mut();
811 if let IncrCompSession
::NotInitialized
= *incr_comp_session
{
813 panic
!("Trying to initialize IncrCompSession `{:?}`", *incr_comp_session
)
817 IncrCompSession
::Active { session_directory: session_dir, lock_file, load_dep_graph }
;
820 pub fn finalize_incr_comp_session(&self, new_directory_path
: PathBuf
) {
821 let mut incr_comp_session
= self.incr_comp_session
.borrow_mut();
823 if let IncrCompSession
::Active { .. }
= *incr_comp_session
{
825 panic
!("trying to finalize `IncrCompSession` `{:?}`", *incr_comp_session
);
828 // Note: this will also drop the lock file, thus unlocking the directory.
829 *incr_comp_session
= IncrCompSession
::Finalized { session_directory: new_directory_path }
;
832 pub fn mark_incr_comp_session_as_invalid(&self) {
833 let mut incr_comp_session
= self.incr_comp_session
.borrow_mut();
835 let session_directory
= match *incr_comp_session
{
836 IncrCompSession
::Active { ref session_directory, .. }
=> session_directory
.clone(),
837 IncrCompSession
::InvalidBecauseOfErrors { .. }
=> return,
838 _
=> panic
!("trying to invalidate `IncrCompSession` `{:?}`", *incr_comp_session
),
841 // Note: this will also drop the lock file, thus unlocking the directory.
842 *incr_comp_session
= IncrCompSession
::InvalidBecauseOfErrors { session_directory }
;
845 pub fn incr_comp_session_dir(&self) -> cell
::Ref
<'_
, PathBuf
> {
846 let incr_comp_session
= self.incr_comp_session
.borrow();
847 cell
::Ref
::map(incr_comp_session
, |incr_comp_session
| match *incr_comp_session
{
848 IncrCompSession
::NotInitialized
=> panic
!(
849 "trying to get session directory from `IncrCompSession`: {:?}",
852 IncrCompSession
::Active { ref session_directory, .. }
853 | IncrCompSession
::Finalized { ref session_directory }
854 | IncrCompSession
::InvalidBecauseOfErrors { ref session_directory }
=> {
860 pub fn incr_comp_session_dir_opt(&self) -> Option
<cell
::Ref
<'_
, PathBuf
>> {
861 self.opts
.incremental
.as_ref().map(|_
| self.incr_comp_session_dir())
864 pub fn print_perf_stats(&self) {
866 "Total time spent computing symbol hashes: {}",
867 duration_to_secs_str(*self.perf_stats
.symbol_hash_time
.lock())
870 "Total queries canonicalized: {}",
871 self.perf_stats
.queries_canonicalized
.load(Ordering
::Relaxed
)
874 "normalize_generic_arg_after_erasing_regions: {}",
875 self.perf_stats
.normalize_generic_arg_after_erasing_regions
.load(Ordering
::Relaxed
)
878 "normalize_projection_ty: {}",
879 self.perf_stats
.normalize_projection_ty
.load(Ordering
::Relaxed
)
883 /// We want to know if we're allowed to do an optimization for crate foo from -z fuel=foo=n.
884 /// This expends fuel if applicable, and records fuel if applicable.
885 pub fn consider_optimizing
<T
: Fn() -> String
>(&self, crate_name
: &str, msg
: T
) -> bool
{
887 if let Some((ref c
, _
)) = self.opts
.debugging_opts
.fuel
{
889 assert_eq
!(self.threads(), 1);
890 let mut fuel
= self.optimization_fuel
.lock();
891 ret
= fuel
.remaining
!= 0;
892 if fuel
.remaining
== 0 && !fuel
.out_of_fuel
{
893 if self.diagnostic().can_emit_warnings() {
894 // We only call `msg` in case we can actually emit warnings.
895 // Otherwise, this could cause a `delay_good_path_bug` to
896 // trigger (issue #79546).
897 self.warn(&format
!("optimization-fuel-exhausted: {}", msg()));
899 fuel
.out_of_fuel
= true;
900 } else if fuel
.remaining
> 0 {
905 if let Some(ref c
) = self.opts
.debugging_opts
.print_fuel
{
907 assert_eq
!(self.threads(), 1);
908 self.print_fuel
.fetch_add(1, SeqCst
);
914 /// Returns the number of query threads that should be used for this
916 pub fn threads(&self) -> usize {
917 self.opts
.debugging_opts
.threads
920 /// Returns the number of codegen units that should be used for this
922 pub fn codegen_units(&self) -> usize {
923 if let Some(n
) = self.opts
.cli_forced_codegen_units
{
926 if let Some(n
) = self.target
.default_codegen_units
{
930 // If incremental compilation is turned on, we default to a high number
931 // codegen units in order to reduce the "collateral damage" small
933 if self.opts
.incremental
.is_some() {
937 // Why is 16 codegen units the default all the time?
939 // The main reason for enabling multiple codegen units by default is to
940 // leverage the ability for the codegen backend to do codegen and
941 // optimization in parallel. This allows us, especially for large crates, to
942 // make good use of all available resources on the machine once we've
943 // hit that stage of compilation. Large crates especially then often
944 // take a long time in codegen/optimization and this helps us amortize that
947 // Note that a high number here doesn't mean that we'll be spawning a
948 // large number of threads in parallel. The backend of rustc contains
949 // global rate limiting through the `jobserver` crate so we'll never
950 // overload the system with too much work, but rather we'll only be
951 // optimizing when we're otherwise cooperating with other instances of
954 // Rather a high number here means that we should be able to keep a lot
955 // of idle cpus busy. By ensuring that no codegen unit takes *too* long
956 // to build we'll be guaranteed that all cpus will finish pretty closely
957 // to one another and we should make relatively optimal use of system
960 // Note that the main cost of codegen units is that it prevents LLVM
961 // from inlining across codegen units. Users in general don't have a lot
962 // of control over how codegen units are split up so it's our job in the
963 // compiler to ensure that undue performance isn't lost when using
964 // codegen units (aka we can't require everyone to slap `#[inline]` on
967 // If we're compiling at `-O0` then the number doesn't really matter too
968 // much because performance doesn't matter and inlining is ok to lose.
969 // In debug mode we just want to try to guarantee that no cpu is stuck
970 // doing work that could otherwise be farmed to others.
972 // In release mode, however (O1 and above) performance does indeed
973 // matter! To recover the loss in performance due to inlining we'll be
974 // enabling ThinLTO by default (the function for which is just below).
975 // This will ensure that we recover any inlining wins we otherwise lost
976 // through codegen unit partitioning.
980 // Ok that's a lot of words but the basic tl;dr; is that we want a high
981 // number here -- but not too high. Additionally we're "safe" to have it
982 // always at the same number at all optimization levels.
984 // As a result 16 was chosen here! Mostly because it was a power of 2
985 // and most benchmarks agreed it was roughly a local optimum. Not very
990 pub fn teach(&self, code
: &DiagnosticId
) -> bool
{
991 self.opts
.debugging_opts
.teach
&& self.diagnostic().must_teach(code
)
994 pub fn rust_2015(&self) -> bool
{
995 self.opts
.edition
== Edition
::Edition2015
998 /// Are we allowed to use features from the Rust 2018 edition?
999 pub fn rust_2018(&self) -> bool
{
1000 self.opts
.edition
>= Edition
::Edition2018
1003 /// Are we allowed to use features from the Rust 2021 edition?
1004 pub fn rust_2021(&self) -> bool
{
1005 self.opts
.edition
>= Edition
::Edition2021
1008 pub fn edition(&self) -> Edition
{
1012 /// Returns `true` if we cannot skip the PLT for shared library calls.
1013 pub fn needs_plt(&self) -> bool
{
1014 // Check if the current target usually needs PLT to be enabled.
1015 // The user can use the command line flag to override it.
1016 let needs_plt
= self.target
.needs_plt
;
1018 let dbg_opts
= &self.opts
.debugging_opts
;
1020 let relro_level
= dbg_opts
.relro_level
.unwrap_or(self.target
.relro_level
);
1022 // Only enable this optimization by default if full relro is also enabled.
1023 // In this case, lazy binding was already unavailable, so nothing is lost.
1024 // This also ensures `-Wl,-z,now` is supported by the linker.
1025 let full_relro
= RelroLevel
::Full
== relro_level
;
1027 // If user didn't explicitly forced us to use / skip the PLT,
1028 // then try to skip it where possible.
1029 dbg_opts
.plt
.unwrap_or(needs_plt
|| !full_relro
)
1032 /// Checks if LLVM lifetime markers should be emitted.
1033 pub fn emit_lifetime_markers(&self) -> bool
{
1034 self.opts
.optimize
!= config
::OptLevel
::No
1035 // AddressSanitizer uses lifetimes to detect use after scope bugs.
1036 // MemorySanitizer uses lifetimes to detect use of uninitialized stack variables.
1037 // HWAddressSanitizer will use lifetimes to detect use after scope bugs in the future.
1038 || self.opts
.debugging_opts
.sanitizer
.intersects(SanitizerSet
::ADDRESS
| SanitizerSet
::MEMORY
| SanitizerSet
::HWADDRESS
)
1041 pub fn link_dead_code(&self) -> bool
{
1042 self.opts
.cg
.link_dead_code
.unwrap_or(false)
1045 pub fn instrument_coverage(&self) -> bool
{
1046 self.opts
.instrument_coverage()
1049 pub fn instrument_coverage_except_unused_generics(&self) -> bool
{
1050 self.opts
.instrument_coverage_except_unused_generics()
1053 pub fn instrument_coverage_except_unused_functions(&self) -> bool
{
1054 self.opts
.instrument_coverage_except_unused_functions()
1057 pub fn is_proc_macro_attr(&self, attr
: &Attribute
) -> bool
{
1058 [sym
::proc_macro
, sym
::proc_macro_attribute
, sym
::proc_macro_derive
]
1060 .any(|kind
| attr
.has_name(*kind
))
1063 pub fn contains_name(&self, attrs
: &[Attribute
], name
: Symbol
) -> bool
{
1064 attrs
.iter().any(|item
| item
.has_name(name
))
1067 pub fn find_by_name
<'a
>(
1069 attrs
: &'a
[Attribute
],
1071 ) -> Option
<&'a Attribute
> {
1072 attrs
.iter().find(|attr
| attr
.has_name(name
))
1075 pub fn filter_by_name
<'a
>(
1077 attrs
: &'a
[Attribute
],
1079 ) -> impl Iterator
<Item
= &'a Attribute
> {
1080 attrs
.iter().filter(move |attr
| attr
.has_name(name
))
1083 pub fn first_attr_value_str_by_name(
1085 attrs
: &[Attribute
],
1087 ) -> Option
<Symbol
> {
1088 attrs
.iter().find(|at
| at
.has_name(name
)).and_then(|at
| at
.value_str())
1093 sopts
: &config
::Options
,
1094 registry
: rustc_errors
::registry
::Registry
,
1095 source_map
: Lrc
<SourceMap
>,
1096 emitter_dest
: Option
<Box
<dyn Write
+ Send
>>,
1097 ) -> Box
<dyn Emitter
+ sync
::Send
> {
1098 let macro_backtrace
= sopts
.debugging_opts
.macro_backtrace
;
1099 match (sopts
.error_format
, emitter_dest
) {
1100 (config
::ErrorOutputType
::HumanReadable(kind
), dst
) => {
1101 let (short
, color_config
) = kind
.unzip();
1103 if let HumanReadableErrorType
::AnnotateSnippet(_
) = kind
{
1105 AnnotateSnippetEmitterWriter
::new(Some(source_map
), short
, macro_backtrace
);
1106 Box
::new(emitter
.ui_testing(sopts
.debugging_opts
.ui_testing
))
1108 let emitter
= match dst
{
1109 None
=> EmitterWriter
::stderr(
1113 sopts
.debugging_opts
.teach
,
1114 sopts
.debugging_opts
.terminal_width
,
1117 Some(dst
) => EmitterWriter
::new(
1121 false, // no teach messages when writing to a buffer
1122 false, // no colors when writing to a buffer
1123 None
, // no terminal width
1127 Box
::new(emitter
.ui_testing(sopts
.debugging_opts
.ui_testing
))
1130 (config
::ErrorOutputType
::Json { pretty, json_rendered }
, None
) => Box
::new(
1131 JsonEmitter
::stderr(
1136 sopts
.debugging_opts
.terminal_width
,
1139 .ui_testing(sopts
.debugging_opts
.ui_testing
),
1141 (config
::ErrorOutputType
::Json { pretty, json_rendered }
, Some(dst
)) => Box
::new(
1148 sopts
.debugging_opts
.terminal_width
,
1151 .ui_testing(sopts
.debugging_opts
.ui_testing
),
1156 pub enum DiagnosticOutput
{
1158 Raw(Box
<dyn Write
+ Send
>),
1161 pub fn build_session(
1162 sopts
: config
::Options
,
1163 local_crate_source_file
: Option
<PathBuf
>,
1164 registry
: rustc_errors
::registry
::Registry
,
1165 diagnostics_output
: DiagnosticOutput
,
1166 driver_lint_caps
: FxHashMap
<lint
::LintId
, lint
::Level
>,
1167 file_loader
: Option
<Box
<dyn FileLoader
+ Send
+ Sync
+ '
static>>,
1168 target_override
: Option
<Target
>,
1170 // FIXME: This is not general enough to make the warning lint completely override
1171 // normal diagnostic warnings, since the warning lint can also be denied and changed
1172 // later via the source code.
1173 let warnings_allow
= sopts
1176 .filter(|&&(ref key
, _
)| *key
== "warnings")
1177 .map(|&(_
, ref level
)| *level
== lint
::Allow
)
1180 let cap_lints_allow
= sopts
.lint_cap
.map_or(false, |cap
| cap
== lint
::Allow
);
1181 let can_emit_warnings
= !(warnings_allow
|| cap_lints_allow
);
1183 let write_dest
= match diagnostics_output
{
1184 DiagnosticOutput
::Default
=> None
,
1185 DiagnosticOutput
::Raw(write
) => Some(write
),
1188 let sysroot
= match &sopts
.maybe_sysroot
{
1189 Some(sysroot
) => sysroot
.clone(),
1190 None
=> filesearch
::get_or_default_sysroot(),
1193 let target_cfg
= config
::build_target_config(&sopts
, target_override
, &sysroot
);
1194 let host_triple
= TargetTriple
::from_triple(config
::host_triple());
1195 let (host
, target_warnings
) = Target
::search(&host_triple
, &sysroot
).unwrap_or_else(|e
| {
1196 early_error(sopts
.error_format
, &format
!("Error loading host specification: {}", e
))
1198 for warning
in target_warnings
.warning_messages() {
1199 early_warn(sopts
.error_format
, &warning
)
1202 let loader
= file_loader
.unwrap_or_else(|| Box
::new(RealFileLoader
));
1203 let hash_kind
= sopts
.debugging_opts
.src_hash_algorithm
.unwrap_or_else(|| {
1204 if target_cfg
.is_like_msvc
{
1205 SourceFileHashAlgorithm
::Sha1
1207 SourceFileHashAlgorithm
::Md5
1210 let source_map
= Lrc
::new(SourceMap
::with_file_loader_and_hash_kind(
1212 sopts
.file_path_mapping(),
1215 let emitter
= default_emitter(&sopts
, registry
, source_map
.clone(), write_dest
);
1217 let span_diagnostic
= rustc_errors
::Handler
::with_emitter_and_flags(
1219 sopts
.debugging_opts
.diagnostic_handler_flags(can_emit_warnings
),
1222 let self_profiler
= if let SwitchWithOptPath
::Enabled(ref d
) = sopts
.debugging_opts
.self_profile
1225 if let Some(ref directory
) = d { directory }
else { std::path::Path::new(".") }
;
1227 let profiler
= SelfProfiler
::new(
1229 sopts
.crate_name
.as_deref(),
1230 &sopts
.debugging_opts
.self_profile_events
,
1233 Ok(profiler
) => Some(Arc
::new(profiler
)),
1235 early_warn(sopts
.error_format
, &format
!("failed to create profiler: {}", e
));
1243 let mut parse_sess
= ParseSess
::with_span_handler(span_diagnostic
, source_map
);
1244 parse_sess
.assume_incomplete_release
= sopts
.debugging_opts
.assume_incomplete_release
;
1246 let host_triple
= config
::host_triple();
1247 let target_triple
= sopts
.target_triple
.triple();
1248 let host_tlib_path
= Lrc
::new(SearchPath
::from_sysroot_and_triple(&sysroot
, host_triple
));
1249 let target_tlib_path
= if host_triple
== target_triple
{
1250 // Use the same `SearchPath` if host and target triple are identical to avoid unnecessary
1251 // rescanning of the target lib path and an unnecessary allocation.
1252 host_tlib_path
.clone()
1254 Lrc
::new(SearchPath
::from_sysroot_and_triple(&sysroot
, target_triple
))
1257 let file_path_mapping
= sopts
.file_path_mapping();
1259 let local_crate_source_file
=
1260 local_crate_source_file
.map(|path
| file_path_mapping
.map_prefix(path
).0);
1262 let optimization_fuel
= Lock
::new(OptimizationFuel
{
1263 remaining
: sopts
.debugging_opts
.fuel
.as_ref().map_or(0, |i
| i
.1),
1266 let print_fuel
= AtomicU64
::new(0);
1268 let cgu_reuse_tracker
= if sopts
.debugging_opts
.query_dep_graph
{
1269 CguReuseTracker
::new()
1271 CguReuseTracker
::new_disabled()
1274 let prof
= SelfProfilerRef
::new(
1276 sopts
.debugging_opts
.time_passes
|| sopts
.debugging_opts
.time
,
1277 sopts
.debugging_opts
.time_passes
,
1280 let ctfe_backtrace
= Lock
::new(match env
::var("RUSTC_CTFE_BACKTRACE") {
1281 Ok(ref val
) if val
== "immediate" => CtfeBacktrace
::Immediate
,
1282 Ok(ref val
) if val
!= "0" => CtfeBacktrace
::Capture
,
1283 _
=> CtfeBacktrace
::Disabled
,
1287 if target_cfg
.allow_asm { InlineAsmArch::from_str(&target_cfg.arch).ok() }
else { None }
;
1289 let sess
= Session
{
1297 local_crate_source_file
,
1298 one_time_diagnostics
: Default
::default(),
1299 crate_types
: OnceCell
::new(),
1300 stable_crate_id
: OnceCell
::new(),
1301 features
: OnceCell
::new(),
1302 incr_comp_session
: OneThread
::new(RefCell
::new(IncrCompSession
::NotInitialized
)),
1305 perf_stats
: PerfStats
{
1306 symbol_hash_time
: Lock
::new(Duration
::from_secs(0)),
1307 queries_canonicalized
: AtomicUsize
::new(0),
1308 normalize_generic_arg_after_erasing_regions
: AtomicUsize
::new(0),
1309 normalize_projection_ty
: AtomicUsize
::new(0),
1311 code_stats
: Default
::default(),
1314 jobserver
: jobserver
::client(),
1317 miri_unleashed_features
: Lock
::new(Default
::default()),
1319 target_features
: FxHashSet
::default(),
1322 validate_commandline_args_with_session_available(&sess
);
1327 // If it is useful to have a Session available already for validating a
1328 // commandline argument, you can do so here.
1329 fn validate_commandline_args_with_session_available(sess
: &Session
) {
1330 // Since we don't know if code in an rlib will be linked to statically or
1331 // dynamically downstream, rustc generates `__imp_` symbols that help linkers
1332 // on Windows deal with this lack of knowledge (#27438). Unfortunately,
1333 // these manually generated symbols confuse LLD when it tries to merge
1334 // bitcode during ThinLTO. Therefore we disallow dynamic linking on Windows
1335 // when compiling for LLD ThinLTO. This way we can validly just not generate
1336 // the `dllimport` attributes and `__imp_` symbols in that case.
1337 if sess
.opts
.cg
.linker_plugin_lto
.enabled()
1338 && sess
.opts
.cg
.prefer_dynamic
1339 && sess
.target
.is_like_windows
1342 "Linker plugin based LTO is not supported together with \
1343 `-C prefer-dynamic` when targeting Windows-like targets",
1347 // Make sure that any given profiling data actually exists so LLVM can't
1348 // decide to silently skip PGO.
1349 if let Some(ref path
) = sess
.opts
.cg
.profile_use
{
1352 "File `{}` passed to `-C profile-use` does not exist.",
1358 // Do the same for sample profile data.
1359 if let Some(ref path
) = sess
.opts
.debugging_opts
.profile_sample_use
{
1362 "File `{}` passed to `-C profile-sample-use` does not exist.",
1368 // Unwind tables cannot be disabled if the target requires them.
1369 if let Some(include_uwtables
) = sess
.opts
.cg
.force_unwind_tables
{
1370 if sess
.target
.requires_uwtable
&& !include_uwtables
{
1372 "target requires unwind tables, they cannot be disabled with \
1373 `-C force-unwind-tables=no`.",
1378 // Sanitizers can only be used on platforms that we know have working sanitizer codegen.
1379 let supported_sanitizers
= sess
.target
.options
.supported_sanitizers
;
1380 let unsupported_sanitizers
= sess
.opts
.debugging_opts
.sanitizer
- supported_sanitizers
;
1381 match unsupported_sanitizers
.into_iter().count() {
1384 .err(&format
!("{} sanitizer is not supported for this target", unsupported_sanitizers
)),
1385 _
=> sess
.err(&format
!(
1386 "{} sanitizers are not supported for this target",
1387 unsupported_sanitizers
1390 // Cannot mix and match sanitizers.
1391 let mut sanitizer_iter
= sess
.opts
.debugging_opts
.sanitizer
.into_iter();
1392 if let (Some(first
), Some(second
)) = (sanitizer_iter
.next(), sanitizer_iter
.next()) {
1393 sess
.err(&format
!("`-Zsanitizer={}` is incompatible with `-Zsanitizer={}`", first
, second
));
1396 // Cannot enable crt-static with sanitizers on Linux
1397 if sess
.crt_static(None
) && !sess
.opts
.debugging_opts
.sanitizer
.is_empty() {
1399 "sanitizer is incompatible with statically linked libc, \
1400 disable it using `-C target-feature=-crt-static`",
1404 // LLVM CFI requires LTO.
1405 if sess
.is_sanitizer_cfi_enabled() {
1406 if sess
.opts
.cg
.lto
== config
::LtoCli
::Unspecified
1407 || sess
.opts
.cg
.lto
== config
::LtoCli
::No
1408 || sess
.opts
.cg
.lto
== config
::LtoCli
::Thin
1410 sess
.err("`-Zsanitizer=cfi` requires `-Clto`");
1414 if sess
.opts
.debugging_opts
.stack_protector
!= StackProtector
::None
{
1415 if !sess
.target
.options
.supports_stack_protector
{
1417 "`-Z stack-protector={}` is not supported for target {} and will be ignored",
1418 sess
.opts
.debugging_opts
.stack_protector
, sess
.opts
.target_triple
1424 /// Holds data on the current incremental compilation session, if there is one.
1426 pub enum IncrCompSession
{
1427 /// This is the state the session will be in until the incr. comp. dir is
1430 /// This is the state during which the session directory is private and can
1432 Active { session_directory: PathBuf, lock_file: flock::Lock, load_dep_graph: bool }
,
1433 /// This is the state after the session directory has been finalized. In this
1434 /// state, the contents of the directory must not be modified any more.
1435 Finalized { session_directory: PathBuf }
,
1436 /// This is an error state that is reached when some compilation error has
1437 /// occurred. It indicates that the contents of the session directory must
1438 /// not be used, since they might be invalid.
1439 InvalidBecauseOfErrors { session_directory: PathBuf }
,
1442 pub fn early_error_no_abort(output
: config
::ErrorOutputType
, msg
: &str) {
1443 let emitter
: Box
<dyn Emitter
+ sync
::Send
> = match output
{
1444 config
::ErrorOutputType
::HumanReadable(kind
) => {
1445 let (short
, color_config
) = kind
.unzip();
1446 Box
::new(EmitterWriter
::stderr(color_config
, None
, short
, false, None
, false))
1448 config
::ErrorOutputType
::Json { pretty, json_rendered }
=> {
1449 Box
::new(JsonEmitter
::basic(pretty
, json_rendered
, None
, false))
1452 let handler
= rustc_errors
::Handler
::with_emitter(true, None
, emitter
);
1453 handler
.struct_fatal(msg
).emit();
1456 pub fn early_error(output
: config
::ErrorOutputType
, msg
: &str) -> ! {
1457 early_error_no_abort(output
, msg
);
1458 rustc_errors
::FatalError
.raise();
1461 pub fn early_warn(output
: config
::ErrorOutputType
, msg
: &str) {
1462 let emitter
: Box
<dyn Emitter
+ sync
::Send
> = match output
{
1463 config
::ErrorOutputType
::HumanReadable(kind
) => {
1464 let (short
, color_config
) = kind
.unzip();
1465 Box
::new(EmitterWriter
::stderr(color_config
, None
, short
, false, None
, false))
1467 config
::ErrorOutputType
::Json { pretty, json_rendered }
=> {
1468 Box
::new(JsonEmitter
::basic(pretty
, json_rendered
, None
, false))
1471 let handler
= rustc_errors
::Handler
::with_emitter(true, None
, emitter
);
1472 handler
.struct_warn(msg
).emit();