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223e47cc | 1 | //! Finds crate binaries and loads their metadata |
1a4d82fc JJ |
2 | //! |
3 | //! Might I be the first to welcome you to a world of platform differences, | |
4 | //! version requirements, dependency graphs, conflicting desires, and fun! This | |
5 | //! is the major guts (along with metadata::creader) of the compiler for loading | |
6 | //! crates and resolving dependencies. Let's take a tour! | |
7 | //! | |
8 | //! # The problem | |
9 | //! | |
10 | //! Each invocation of the compiler is immediately concerned with one primary | |
11 | //! problem, to connect a set of crates to resolved crates on the filesystem. | |
12 | //! Concretely speaking, the compiler follows roughly these steps to get here: | |
13 | //! | |
14 | //! 1. Discover a set of `extern crate` statements. | |
15 | //! 2. Transform these directives into crate names. If the directive does not | |
16 | //! have an explicit name, then the identifier is the name. | |
17 | //! 3. For each of these crate names, find a corresponding crate on the | |
18 | //! filesystem. | |
19 | //! | |
20 | //! Sounds easy, right? Let's walk into some of the nuances. | |
21 | //! | |
22 | //! ## Transitive Dependencies | |
23 | //! | |
24 | //! Let's say we've got three crates: A, B, and C. A depends on B, and B depends | |
25 | //! on C. When we're compiling A, we primarily need to find and locate B, but we | |
26 | //! also end up needing to find and locate C as well. | |
27 | //! | |
28 | //! The reason for this is that any of B's types could be composed of C's types, | |
29 | //! any function in B could return a type from C, etc. To be able to guarantee | |
9fa01778 | 30 | //! that we can always type-check/translate any function, we have to have |
1a4d82fc JJ |
31 | //! complete knowledge of the whole ecosystem, not just our immediate |
32 | //! dependencies. | |
33 | //! | |
34 | //! So now as part of the "find a corresponding crate on the filesystem" step | |
35 | //! above, this involves also finding all crates for *all upstream | |
36 | //! dependencies*. This includes all dependencies transitively. | |
37 | //! | |
38 | //! ## Rlibs and Dylibs | |
39 | //! | |
40 | //! The compiler has two forms of intermediate dependencies. These are dubbed | |
41 | //! rlibs and dylibs for the static and dynamic variants, respectively. An rlib | |
42 | //! is a rustc-defined file format (currently just an ar archive) while a dylib | |
43 | //! is a platform-defined dynamic library. Each library has a metadata somewhere | |
44 | //! inside of it. | |
45 | //! | |
476ff2be SL |
46 | //! A third kind of dependency is an rmeta file. These are metadata files and do |
47 | //! not contain any code, etc. To a first approximation, these are treated in the | |
48 | //! same way as rlibs. Where there is both an rlib and an rmeta file, the rlib | |
49 | //! gets priority (even if the rmeta file is newer). An rmeta file is only | |
50 | //! useful for checking a downstream crate, attempting to link one will cause an | |
51 | //! error. | |
52 | //! | |
1a4d82fc JJ |
53 | //! When translating a crate name to a crate on the filesystem, we all of a |
54 | //! sudden need to take into account both rlibs and dylibs! Linkage later on may | |
55 | //! use either one of these files, as each has their pros/cons. The job of crate | |
56 | //! loading is to discover what's possible by finding all candidates. | |
57 | //! | |
58 | //! Most parts of this loading systems keep the dylib/rlib as just separate | |
59 | //! variables. | |
60 | //! | |
61 | //! ## Where to look? | |
62 | //! | |
63 | //! We can't exactly scan your whole hard drive when looking for dependencies, | |
64 | //! so we need to places to look. Currently the compiler will implicitly add the | |
65 | //! target lib search path ($prefix/lib/rustlib/$target/lib) to any compilation, | |
66 | //! and otherwise all -L flags are added to the search paths. | |
67 | //! | |
68 | //! ## What criterion to select on? | |
69 | //! | |
70 | //! This a pretty tricky area of loading crates. Given a file, how do we know | |
71 | //! whether it's the right crate? Currently, the rules look along these lines: | |
72 | //! | |
73 | //! 1. Does the filename match an rlib/dylib pattern? That is to say, does the | |
74 | //! filename have the right prefix/suffix? | |
75 | //! 2. Does the filename have the right prefix for the crate name being queried? | |
83c7162d XL |
76 | //! This is filtering for files like `libfoo*.rlib` and such. If the crate |
77 | //! we're looking for was originally compiled with -C extra-filename, the | |
78 | //! extra filename will be included in this prefix to reduce reading | |
79 | //! metadata from crates that would otherwise share our prefix. | |
1a4d82fc JJ |
80 | //! 3. Is the file an actual rust library? This is done by loading the metadata |
81 | //! from the library and making sure it's actually there. | |
82 | //! 4. Does the name in the metadata agree with the name of the library? | |
83 | //! 5. Does the target in the metadata agree with the current target? | |
84 | //! 6. Does the SVH match? (more on this later) | |
85 | //! | |
86 | //! If the file answers `yes` to all these questions, then the file is | |
87 | //! considered as being *candidate* for being accepted. It is illegal to have | |
88 | //! more than two candidates as the compiler has no method by which to resolve | |
89 | //! this conflict. Additionally, rlib/dylib candidates are considered | |
90 | //! separately. | |
91 | //! | |
92 | //! After all this has happened, we have 1 or two files as candidates. These | |
93 | //! represent the rlib/dylib file found for a library, and they're returned as | |
94 | //! being found. | |
95 | //! | |
96 | //! ### What about versions? | |
97 | //! | |
98 | //! A lot of effort has been put forth to remove versioning from the compiler. | |
99 | //! There have been forays in the past to have versioning baked in, but it was | |
100 | //! largely always deemed insufficient to the point that it was recognized that | |
101 | //! it's probably something the compiler shouldn't do anyway due to its | |
102 | //! complicated nature and the state of the half-baked solutions. | |
103 | //! | |
104 | //! With a departure from versioning, the primary criterion for loading crates | |
105 | //! is just the name of a crate. If we stopped here, it would imply that you | |
106 | //! could never link two crates of the same name from different sources | |
107 | //! together, which is clearly a bad state to be in. | |
108 | //! | |
109 | //! To resolve this problem, we come to the next section! | |
110 | //! | |
111 | //! # Expert Mode | |
112 | //! | |
113 | //! A number of flags have been added to the compiler to solve the "version | |
114 | //! problem" in the previous section, as well as generally enabling more | |
115 | //! powerful usage of the crate loading system of the compiler. The goal of | |
116 | //! these flags and options are to enable third-party tools to drive the | |
117 | //! compiler with prior knowledge about how the world should look. | |
118 | //! | |
119 | //! ## The `--extern` flag | |
120 | //! | |
121 | //! The compiler accepts a flag of this form a number of times: | |
122 | //! | |
123 | //! ```text | |
124 | //! --extern crate-name=path/to/the/crate.rlib | |
125 | //! ``` | |
126 | //! | |
127 | //! This flag is basically the following letter to the compiler: | |
128 | //! | |
129 | //! > Dear rustc, | |
130 | //! > | |
131 | //! > When you are attempting to load the immediate dependency `crate-name`, I | |
9346a6ac | 132 | //! > would like you to assume that the library is located at |
1a4d82fc JJ |
133 | //! > `path/to/the/crate.rlib`, and look nowhere else. Also, please do not |
134 | //! > assume that the path I specified has the name `crate-name`. | |
135 | //! | |
136 | //! This flag basically overrides most matching logic except for validating that | |
137 | //! the file is indeed a rust library. The same `crate-name` can be specified | |
138 | //! twice to specify the rlib/dylib pair. | |
139 | //! | |
140 | //! ## Enabling "multiple versions" | |
141 | //! | |
142 | //! This basically boils down to the ability to specify arbitrary packages to | |
143 | //! the compiler. For example, if crate A wanted to use Bv1 and Bv2, then it | |
144 | //! would look something like: | |
145 | //! | |
041b39d2 | 146 | //! ```compile_fail,E0463 |
1a4d82fc JJ |
147 | //! extern crate b1; |
148 | //! extern crate b2; | |
149 | //! | |
150 | //! fn main() {} | |
151 | //! ``` | |
152 | //! | |
153 | //! and the compiler would be invoked as: | |
154 | //! | |
155 | //! ```text | |
156 | //! rustc a.rs --extern b1=path/to/libb1.rlib --extern b2=path/to/libb2.rlib | |
157 | //! ``` | |
158 | //! | |
159 | //! In this scenario there are two crates named `b` and the compiler must be | |
160 | //! manually driven to be informed where each crate is. | |
161 | //! | |
162 | //! ## Frobbing symbols | |
163 | //! | |
164 | //! One of the immediate problems with linking the same library together twice | |
165 | //! in the same problem is dealing with duplicate symbols. The primary way to | |
166 | //! deal with this in rustc is to add hashes to the end of each symbol. | |
167 | //! | |
168 | //! In order to force hashes to change between versions of a library, if | |
169 | //! desired, the compiler exposes an option `-C metadata=foo`, which is used to | |
170 | //! initially seed each symbol hash. The string `foo` is prepended to each | |
171 | //! string-to-hash to ensure that symbols change over time. | |
172 | //! | |
173 | //! ## Loading transitive dependencies | |
174 | //! | |
175 | //! Dealing with same-named-but-distinct crates is not just a local problem, but | |
176 | //! one that also needs to be dealt with for transitive dependencies. Note that | |
177 | //! in the letter above `--extern` flags only apply to the *local* set of | |
178 | //! dependencies, not the upstream transitive dependencies. Consider this | |
179 | //! dependency graph: | |
180 | //! | |
181 | //! ```text | |
182 | //! A.1 A.2 | |
183 | //! | | | |
184 | //! | | | |
185 | //! B C | |
186 | //! \ / | |
187 | //! \ / | |
188 | //! D | |
189 | //! ``` | |
190 | //! | |
191 | //! In this scenario, when we compile `D`, we need to be able to distinctly | |
192 | //! resolve `A.1` and `A.2`, but an `--extern` flag cannot apply to these | |
193 | //! transitive dependencies. | |
194 | //! | |
195 | //! Note that the key idea here is that `B` and `C` are both *already compiled*. | |
196 | //! That is, they have already resolved their dependencies. Due to unrelated | |
197 | //! technical reasons, when a library is compiled, it is only compatible with | |
198 | //! the *exact same* version of the upstream libraries it was compiled against. | |
199 | //! We use the "Strict Version Hash" to identify the exact copy of an upstream | |
200 | //! library. | |
201 | //! | |
202 | //! With this knowledge, we know that `B` and `C` will depend on `A` with | |
203 | //! different SVH values, so we crawl the normal `-L` paths looking for | |
204 | //! `liba*.rlib` and filter based on the contained SVH. | |
205 | //! | |
206 | //! In the end, this ends up not needing `--extern` to specify upstream | |
207 | //! transitive dependencies. | |
208 | //! | |
209 | //! # Wrapping up | |
210 | //! | |
211 | //! That's the general overview of loading crates in the compiler, but it's by | |
212 | //! no means all of the necessary details. Take a look at the rest of | |
c30ab7b3 | 213 | //! metadata::locator or metadata::creader for all the juicy details! |
223e47cc | 214 | |
9fa01778 | 215 | use crate::creader::Library; |
dfeec247 | 216 | use crate::rmeta::{rustc_version, MetadataBlob, METADATA_HEADER}; |
92a42be0 | 217 | |
dfeec247 | 218 | use rustc_data_structures::fx::{FxHashMap, FxHashSet}; |
cdc7bbd5 | 219 | use rustc_data_structures::memmap::Mmap; |
3dfed10e | 220 | use rustc_data_structures::owning_ref::OwningRef; |
dfeec247 XL |
221 | use rustc_data_structures::svh::Svh; |
222 | use rustc_data_structures::sync::MetadataRef; | |
3dfed10e | 223 | use rustc_errors::struct_span_err; |
f9f354fc | 224 | use rustc_session::config::{self, CrateType}; |
c295e0f8 | 225 | use rustc_session::cstore::{CrateSource, MetadataLoader}; |
ba9703b0 XL |
226 | use rustc_session::filesearch::{FileDoesntMatch, FileMatches, FileSearch}; |
227 | use rustc_session::search_paths::PathKind; | |
5869c6ff | 228 | use rustc_session::utils::CanonicalizedPath; |
94222f64 | 229 | use rustc_session::Session; |
dfeec247 XL |
230 | use rustc_span::symbol::{sym, Symbol}; |
231 | use rustc_span::Span; | |
83c7162d | 232 | use rustc_target::spec::{Target, TargetTriple}; |
1a4d82fc | 233 | |
1b1a35ee | 234 | use snap::read::FrameDecoder; |
c295e0f8 | 235 | use std::fmt::Write as _; |
3dfed10e | 236 | use std::io::{Read, Result as IoResult, Write}; |
c34b1796 | 237 | use std::path::{Path, PathBuf}; |
3dfed10e XL |
238 | use std::{cmp, fmt, fs}; |
239 | use tracing::{debug, info, warn}; | |
223e47cc | 240 | |
532ac7d7 | 241 | #[derive(Clone)] |
60c5eb7d XL |
242 | crate struct CrateLocator<'a> { |
243 | // Immutable per-session configuration. | |
c295e0f8 XL |
244 | only_needs_metadata: bool, |
245 | sysroot: &'a Path, | |
60c5eb7d XL |
246 | metadata_loader: &'a dyn MetadataLoader, |
247 | ||
248 | // Immutable per-search configuration. | |
249 | crate_name: Symbol, | |
5869c6ff | 250 | exact_paths: Vec<CanonicalizedPath>, |
60c5eb7d | 251 | pub hash: Option<Svh>, |
60c5eb7d | 252 | extra_filename: Option<&'a str>, |
85aaf69f | 253 | pub target: &'a Target, |
532ac7d7 | 254 | pub triple: TargetTriple, |
1a4d82fc | 255 | pub filesearch: FileSearch<'a>, |
c295e0f8 | 256 | pub is_proc_macro: bool, |
60c5eb7d XL |
257 | |
258 | // Mutable in-progress state or output. | |
c295e0f8 | 259 | crate_rejections: CrateRejections, |
223e47cc LB |
260 | } |
261 | ||
3dfed10e | 262 | #[derive(Clone)] |
e74abb32 | 263 | crate struct CratePaths { |
60c5eb7d XL |
264 | name: Symbol, |
265 | source: CrateSource, | |
266 | } | |
267 | ||
268 | impl CratePaths { | |
269 | crate fn new(name: Symbol, source: CrateSource) -> CratePaths { | |
270 | CratePaths { name, source } | |
271 | } | |
223e47cc LB |
272 | } |
273 | ||
a7813a04 | 274 | #[derive(Copy, Clone, PartialEq)] |
3dfed10e | 275 | crate enum CrateFlavor { |
a7813a04 | 276 | Rlib, |
476ff2be | 277 | Rmeta, |
c30ab7b3 | 278 | Dylib, |
a7813a04 XL |
279 | } |
280 | ||
281 | impl fmt::Display for CrateFlavor { | |
9fa01778 | 282 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
a7813a04 XL |
283 | f.write_str(match *self { |
284 | CrateFlavor::Rlib => "rlib", | |
476ff2be | 285 | CrateFlavor::Rmeta => "rmeta", |
c30ab7b3 | 286 | CrateFlavor::Dylib => "dylib", |
a7813a04 XL |
287 | }) |
288 | } | |
289 | } | |
290 | ||
60c5eb7d XL |
291 | impl<'a> CrateLocator<'a> { |
292 | crate fn new( | |
293 | sess: &'a Session, | |
294 | metadata_loader: &'a dyn MetadataLoader, | |
295 | crate_name: Symbol, | |
296 | hash: Option<Svh>, | |
60c5eb7d XL |
297 | extra_filename: Option<&'a str>, |
298 | is_host: bool, | |
299 | path_kind: PathKind, | |
60c5eb7d | 300 | ) -> CrateLocator<'a> { |
c295e0f8 XL |
301 | // The all loop is because `--crate-type=rlib --crate-type=rlib` is |
302 | // legal and produces both inside this type. | |
303 | let is_rlib = sess.crate_types().iter().all(|c| *c == CrateType::Rlib); | |
304 | let needs_object_code = sess.opts.output_types.should_codegen(); | |
305 | // If we're producing an rlib, then we don't need object code. | |
306 | // Or, if we're not producing object code, then we don't need it either | |
307 | // (e.g., if we're a cdylib but emitting just metadata). | |
308 | let only_needs_metadata = is_rlib || !needs_object_code; | |
309 | ||
60c5eb7d | 310 | CrateLocator { |
c295e0f8 XL |
311 | only_needs_metadata, |
312 | sysroot: &sess.sysroot, | |
60c5eb7d XL |
313 | metadata_loader, |
314 | crate_name, | |
315 | exact_paths: if hash.is_none() { | |
dfeec247 XL |
316 | sess.opts |
317 | .externs | |
318 | .get(&crate_name.as_str()) | |
319 | .into_iter() | |
60c5eb7d XL |
320 | .filter_map(|entry| entry.files()) |
321 | .flatten() | |
5869c6ff | 322 | .cloned() |
dfeec247 | 323 | .collect() |
60c5eb7d XL |
324 | } else { |
325 | // SVH being specified means this is a transitive dependency, | |
326 | // so `--extern` options do not apply. | |
327 | Vec::new() | |
328 | }, | |
329 | hash, | |
60c5eb7d | 330 | extra_filename, |
29967ef6 | 331 | target: if is_host { &sess.host } else { &sess.target }, |
60c5eb7d XL |
332 | triple: if is_host { |
333 | TargetTriple::from_triple(config::host_triple()) | |
334 | } else { | |
335 | sess.opts.target_triple.clone() | |
336 | }, | |
337 | filesearch: if is_host { | |
338 | sess.host_filesearch(path_kind) | |
339 | } else { | |
340 | sess.target_filesearch(path_kind) | |
341 | }, | |
c295e0f8 XL |
342 | is_proc_macro: false, |
343 | crate_rejections: CrateRejections::default(), | |
60c5eb7d XL |
344 | } |
345 | } | |
346 | ||
e74abb32 | 347 | crate fn reset(&mut self) { |
c295e0f8 XL |
348 | self.crate_rejections.via_hash.clear(); |
349 | self.crate_rejections.via_triple.clear(); | |
350 | self.crate_rejections.via_kind.clear(); | |
351 | self.crate_rejections.via_version.clear(); | |
352 | self.crate_rejections.via_filename.clear(); | |
532ac7d7 XL |
353 | } |
354 | ||
3dfed10e | 355 | crate fn maybe_load_library_crate(&mut self) -> Result<Option<Library>, CrateError> { |
60c5eb7d XL |
356 | if !self.exact_paths.is_empty() { |
357 | return self.find_commandline_library(); | |
358 | } | |
b7449926 | 359 | let mut seen_paths = FxHashSet::default(); |
3dfed10e XL |
360 | if let Some(extra_filename) = self.extra_filename { |
361 | if let library @ Some(_) = self.find_library_crate(extra_filename, &mut seen_paths)? { | |
362 | return Ok(library); | |
476ff2be SL |
363 | } |
364 | } | |
3dfed10e | 365 | self.find_library_crate("", &mut seen_paths) |
1a4d82fc JJ |
366 | } |
367 | ||
dfeec247 XL |
368 | fn find_library_crate( |
369 | &mut self, | |
370 | extra_prefix: &str, | |
371 | seen_paths: &mut FxHashSet<PathBuf>, | |
3dfed10e | 372 | ) -> Result<Option<Library>, CrateError> { |
1a4d82fc | 373 | // want: crate_name.dir_part() + prefix + crate_name.file_part + "-" |
29967ef6 | 374 | let dylib_prefix = format!("{}{}{}", self.target.dll_prefix, self.crate_name, extra_prefix); |
83c7162d | 375 | let rlib_prefix = format!("lib{}{}", self.crate_name, extra_prefix); |
3dfed10e | 376 | let staticlib_prefix = |
29967ef6 | 377 | format!("{}{}{}", self.target.staticlib_prefix, self.crate_name, extra_prefix); |
1a4d82fc | 378 | |
dfeec247 XL |
379 | let mut candidates: FxHashMap<_, (FxHashMap<_, _>, FxHashMap<_, _>, FxHashMap<_, _>)> = |
380 | Default::default(); | |
c30ab7b3 | 381 | let mut staticlibs = vec![]; |
1a4d82fc JJ |
382 | |
383 | // First, find all possible candidate rlibs and dylibs purely based on | |
384 | // the name of the files themselves. We're trying to match against an | |
385 | // exact crate name and a possibly an exact hash. | |
386 | // | |
387 | // During this step, we can filter all found libraries based on the | |
388 | // name and id found in the crate id (we ignore the path portion for | |
389 | // filename matching), as well as the exact hash (if specified). If we | |
390 | // end up having many candidates, we must look at the metadata to | |
391 | // perform exact matches against hashes/crate ids. Note that opening up | |
392 | // the metadata is where we do an exact match against the full contents | |
393 | // of the crate id (path/name/id). | |
394 | // | |
395 | // The goal of this step is to look at as little metadata as possible. | |
ba9703b0 XL |
396 | self.filesearch.search(|spf, kind| { |
397 | let file = match &spf.file_name_str { | |
1a4d82fc JJ |
398 | None => return FileDoesntMatch, |
399 | Some(file) => file, | |
400 | }; | |
dfeec247 XL |
401 | let (hash, found_kind) = if file.starts_with(&rlib_prefix) && file.ends_with(".rlib") { |
402 | (&file[(rlib_prefix.len())..(file.len() - ".rlib".len())], CrateFlavor::Rlib) | |
403 | } else if file.starts_with(&rlib_prefix) && file.ends_with(".rmeta") { | |
404 | (&file[(rlib_prefix.len())..(file.len() - ".rmeta".len())], CrateFlavor::Rmeta) | |
29967ef6 | 405 | } else if file.starts_with(&dylib_prefix) && file.ends_with(&self.target.dll_suffix) { |
3dfed10e | 406 | ( |
29967ef6 | 407 | &file[(dylib_prefix.len())..(file.len() - self.target.dll_suffix.len())], |
3dfed10e XL |
408 | CrateFlavor::Dylib, |
409 | ) | |
dfeec247 | 410 | } else { |
3dfed10e | 411 | if file.starts_with(&staticlib_prefix) |
29967ef6 | 412 | && file.ends_with(&self.target.staticlib_suffix) |
3dfed10e | 413 | { |
ba9703b0 XL |
414 | staticlibs |
415 | .push(CrateMismatch { path: spf.path.clone(), got: "static".to_string() }); | |
dfeec247 XL |
416 | } |
417 | return FileDoesntMatch; | |
418 | }; | |
83c7162d | 419 | |
ba9703b0 | 420 | info!("lib candidate: {}", spf.path.display()); |
1a4d82fc | 421 | |
3dfed10e XL |
422 | let (rlibs, rmetas, dylibs) = candidates.entry(hash.to_string()).or_default(); |
423 | let path = fs::canonicalize(&spf.path).unwrap_or_else(|_| spf.path.clone()); | |
424 | if seen_paths.contains(&path) { | |
425 | return FileDoesntMatch; | |
426 | }; | |
427 | seen_paths.insert(path.clone()); | |
428 | match found_kind { | |
429 | CrateFlavor::Rlib => rlibs.insert(path, kind), | |
430 | CrateFlavor::Rmeta => rmetas.insert(path, kind), | |
431 | CrateFlavor::Dylib => dylibs.insert(path, kind), | |
432 | }; | |
433 | FileMatches | |
1a4d82fc | 434 | }); |
c295e0f8 | 435 | self.crate_rejections.via_kind.extend(staticlibs); |
1a4d82fc JJ |
436 | |
437 | // We have now collected all known libraries into a set of candidates | |
438 | // keyed of the filename hash listed. For each filename, we also have a | |
439 | // list of rlibs/dylibs that apply. Here, we map each of these lists | |
440 | // (per hash), to a Library candidate for returning. | |
441 | // | |
442 | // A Library candidate is created if the metadata for the set of | |
443 | // libraries corresponds to the crate id and hash criteria that this | |
444 | // search is being performed for. | |
0bf4aa26 | 445 | let mut libraries = FxHashMap::default(); |
476ff2be | 446 | for (_hash, (rlibs, rmetas, dylibs)) in candidates { |
3dfed10e | 447 | if let Some((svh, lib)) = self.extract_lib(rlibs, rmetas, dylibs)? { |
e74abb32 | 448 | libraries.insert(svh, lib); |
1a4d82fc JJ |
449 | } |
450 | } | |
451 | ||
452 | // Having now translated all relevant found hashes into libraries, see | |
453 | // what we've got and figure out if we found multiple candidates for | |
454 | // libraries or not. | |
455 | match libraries.len() { | |
3dfed10e XL |
456 | 0 => Ok(None), |
457 | 1 => Ok(Some(libraries.into_iter().next().unwrap().1)), | |
458 | _ => Err(CrateError::MultipleMatchingCrates(self.crate_name, libraries)), | |
1a4d82fc JJ |
459 | } |
460 | } | |
461 | ||
e74abb32 XL |
462 | fn extract_lib( |
463 | &mut self, | |
464 | rlibs: FxHashMap<PathBuf, PathKind>, | |
465 | rmetas: FxHashMap<PathBuf, PathKind>, | |
466 | dylibs: FxHashMap<PathBuf, PathKind>, | |
3dfed10e | 467 | ) -> Result<Option<(Svh, Library)>, CrateError> { |
e74abb32 | 468 | let mut slot = None; |
dfeec247 XL |
469 | // Order here matters, rmeta should come first. See comment in |
470 | // `extract_one` below. | |
e74abb32 | 471 | let source = CrateSource { |
3dfed10e XL |
472 | rmeta: self.extract_one(rmetas, CrateFlavor::Rmeta, &mut slot)?, |
473 | rlib: self.extract_one(rlibs, CrateFlavor::Rlib, &mut slot)?, | |
474 | dylib: self.extract_one(dylibs, CrateFlavor::Dylib, &mut slot)?, | |
e74abb32 | 475 | }; |
3dfed10e | 476 | Ok(slot.map(|(svh, metadata)| (svh, Library { source, metadata }))) |
e74abb32 XL |
477 | } |
478 | ||
dfeec247 | 479 | fn needs_crate_flavor(&self, flavor: CrateFlavor) -> bool { |
c295e0f8 | 480 | if flavor == CrateFlavor::Dylib && self.is_proc_macro { |
dfeec247 XL |
481 | return true; |
482 | } | |
483 | ||
c295e0f8 | 484 | if self.only_needs_metadata { |
dfeec247 XL |
485 | flavor == CrateFlavor::Rmeta |
486 | } else { | |
487 | // we need all flavors (perhaps not true, but what we do for now) | |
488 | true | |
489 | } | |
490 | } | |
491 | ||
1a4d82fc JJ |
492 | // Attempts to extract *one* library from the set `m`. If the set has no |
493 | // elements, `None` is returned. If the set has more than one element, then | |
494 | // the errors and notes are emitted about the set of libraries. | |
495 | // | |
496 | // With only one library in the set, this function will extract it, and then | |
497 | // read the metadata from it if `*slot` is `None`. If the metadata couldn't | |
498 | // be read, it is assumed that the file isn't a valid rust library (no | |
499 | // errors are emitted). | |
dfeec247 XL |
500 | fn extract_one( |
501 | &mut self, | |
502 | m: FxHashMap<PathBuf, PathKind>, | |
503 | flavor: CrateFlavor, | |
504 | slot: &mut Option<(Svh, MetadataBlob)>, | |
3dfed10e | 505 | ) -> Result<Option<(PathBuf, PathKind)>, CrateError> { |
dfeec247 XL |
506 | // If we are producing an rlib, and we've already loaded metadata, then |
507 | // we should not attempt to discover further crate sources (unless we're | |
508 | // locating a proc macro; exact logic is in needs_crate_flavor). This means | |
509 | // that under -Zbinary-dep-depinfo we will not emit a dependency edge on | |
510 | // the *unused* rlib, and by returning `None` here immediately we | |
511 | // guarantee that we do indeed not use it. | |
512 | // | |
513 | // See also #68149 which provides more detail on why emitting the | |
514 | // dependency on the rlib is a bad thing. | |
515 | // | |
74b04a01 | 516 | // We currently do not verify that these other sources are even in sync, |
dfeec247 XL |
517 | // and this is arguably a bug (see #10786), but because reading metadata |
518 | // is quite slow (especially from dylibs) we currently do not read it | |
519 | // from the other crate sources. | |
1a4d82fc | 520 | if slot.is_some() { |
dfeec247 | 521 | if m.is_empty() || !self.needs_crate_flavor(flavor) { |
3dfed10e | 522 | return Ok(None); |
1a4d82fc | 523 | } else if m.len() == 1 { |
3dfed10e | 524 | return Ok(Some(m.into_iter().next().unwrap())); |
1a4d82fc JJ |
525 | } |
526 | } | |
527 | ||
3dfed10e XL |
528 | let mut ret: Option<(PathBuf, PathKind)> = None; |
529 | let mut err_data: Option<Vec<PathBuf>> = None; | |
85aaf69f | 530 | for (lib, kind) in m { |
1a4d82fc | 531 | info!("{} reading metadata from: {}", flavor, lib.display()); |
c295e0f8 XL |
532 | if flavor == CrateFlavor::Rmeta && lib.metadata().map_or(false, |m| m.len() == 0) { |
533 | // Empty files will cause get_metadata_section to fail. Rmeta | |
534 | // files can be empty, for example with binaries (which can | |
535 | // often appear with `cargo check` when checking a library as | |
536 | // a unittest). We don't want to emit a user-visible warning | |
537 | // in this case as it is not a real problem. | |
538 | debug!("skipping empty file"); | |
539 | continue; | |
540 | } | |
7cac9316 XL |
541 | let (hash, metadata) = |
542 | match get_metadata_section(self.target, flavor, &lib, self.metadata_loader) { | |
543 | Ok(blob) => { | |
544 | if let Some(h) = self.crate_matches(&blob, &lib) { | |
545 | (h, blob) | |
546 | } else { | |
547 | info!("metadata mismatch"); | |
548 | continue; | |
549 | } | |
550 | } | |
551 | Err(err) => { | |
0bf4aa26 | 552 | warn!("no metadata found: {}", err); |
c30ab7b3 | 553 | continue; |
1a4d82fc | 554 | } |
7cac9316 | 555 | }; |
a7813a04 XL |
556 | // If we see multiple hashes, emit an error about duplicate candidates. |
557 | if slot.as_ref().map_or(false, |s| s.0 != hash) { | |
3dfed10e XL |
558 | if let Some(candidates) = err_data { |
559 | return Err(CrateError::MultipleCandidates( | |
560 | self.crate_name, | |
561 | flavor, | |
562 | candidates, | |
563 | )); | |
9cc50fc6 | 564 | } |
3dfed10e | 565 | err_data = Some(vec![ret.as_ref().unwrap().0.clone()]); |
a7813a04 | 566 | *slot = None; |
1a4d82fc | 567 | } |
3dfed10e XL |
568 | if let Some(candidates) = &mut err_data { |
569 | candidates.push(lib); | |
c30ab7b3 | 570 | continue; |
970d7e83 | 571 | } |
8bb4bdeb XL |
572 | |
573 | // Ok so at this point we've determined that `(lib, kind)` above is | |
574 | // a candidate crate to load, and that `slot` is either none (this | |
575 | // is the first crate of its kind) or if some the previous path has | |
0731742a | 576 | // the exact same hash (e.g., it's the exact same crate). |
8bb4bdeb XL |
577 | // |
578 | // In principle these two candidate crates are exactly the same so | |
579 | // we can choose either of them to link. As a stupidly gross hack, | |
580 | // however, we favor crate in the sysroot. | |
581 | // | |
582 | // You can find more info in rust-lang/rust#39518 and various linked | |
583 | // issues, but the general gist is that during testing libstd the | |
584 | // compilers has two candidates to choose from: one in the sysroot | |
585 | // and one in the deps folder. These two crates are the exact same | |
586 | // crate but if the compiler chooses the one in the deps folder | |
587 | // it'll cause spurious errors on Windows. | |
588 | // | |
589 | // As a result, we favor the sysroot crate here. Note that the | |
590 | // candidates are all canonicalized, so we canonicalize the sysroot | |
591 | // as well. | |
3dfed10e | 592 | if let Some((prev, _)) = &ret { |
c295e0f8 | 593 | let sysroot = self.sysroot; |
dfeec247 | 594 | let sysroot = sysroot.canonicalize().unwrap_or_else(|_| sysroot.to_path_buf()); |
8bb4bdeb | 595 | if prev.starts_with(&sysroot) { |
dfeec247 | 596 | continue; |
8bb4bdeb XL |
597 | } |
598 | } | |
a7813a04 | 599 | *slot = Some((hash, metadata)); |
85aaf69f | 600 | ret = Some((lib, kind)); |
1a4d82fc | 601 | } |
9cc50fc6 | 602 | |
3dfed10e XL |
603 | if let Some(candidates) = err_data { |
604 | Err(CrateError::MultipleCandidates(self.crate_name, flavor, candidates)) | |
9cc50fc6 | 605 | } else { |
3dfed10e | 606 | Ok(ret) |
9cc50fc6 | 607 | } |
1a4d82fc JJ |
608 | } |
609 | ||
9e0c209e | 610 | fn crate_matches(&mut self, metadata: &MetadataBlob, libpath: &Path) -> Option<Svh> { |
c30ab7b3 | 611 | let rustc_version = rustc_version(); |
476ff2be SL |
612 | let found_version = metadata.get_rustc_version(); |
613 | if found_version != rustc_version { | |
dfeec247 | 614 | info!("Rejecting via version: expected {} got {}", rustc_version, found_version); |
c295e0f8 XL |
615 | self.crate_rejections |
616 | .via_version | |
dfeec247 | 617 | .push(CrateMismatch { path: libpath.to_path_buf(), got: found_version }); |
a7813a04 XL |
618 | return None; |
619 | } | |
620 | ||
476ff2be | 621 | let root = metadata.get_root(); |
c295e0f8 XL |
622 | if root.is_proc_macro_crate() != self.is_proc_macro { |
623 | info!( | |
624 | "Rejecting via proc macro: expected {} got {}", | |
625 | self.is_proc_macro, | |
626 | root.is_proc_macro_crate(), | |
627 | ); | |
628 | return None; | |
476ff2be SL |
629 | } |
630 | ||
29967ef6 XL |
631 | if self.exact_paths.is_empty() && self.crate_name != root.name() { |
632 | info!("Rejecting via crate name"); | |
633 | return None; | |
1a4d82fc | 634 | } |
1a4d82fc | 635 | |
60c5eb7d | 636 | if root.triple() != &self.triple { |
dfeec247 | 637 | info!("Rejecting via crate triple: expected {} got {}", self.triple, root.triple()); |
c295e0f8 | 638 | self.crate_rejections.via_triple.push(CrateMismatch { |
c34b1796 | 639 | path: libpath.to_path_buf(), |
60c5eb7d | 640 | got: root.triple().to_string(), |
1a4d82fc | 641 | }); |
a7813a04 | 642 | return None; |
223e47cc | 643 | } |
223e47cc | 644 | |
60c5eb7d XL |
645 | let hash = root.hash(); |
646 | if let Some(expected_hash) = self.hash { | |
647 | if hash != expected_hash { | |
648 | info!("Rejecting via hash: expected {} got {}", expected_hash, hash); | |
c295e0f8 XL |
649 | self.crate_rejections |
650 | .via_hash | |
dfeec247 | 651 | .push(CrateMismatch { path: libpath.to_path_buf(), got: hash.to_string() }); |
a7813a04 | 652 | return None; |
1a4d82fc | 653 | } |
223e47cc | 654 | } |
a7813a04 | 655 | |
60c5eb7d | 656 | Some(hash) |
223e47cc | 657 | } |
223e47cc | 658 | |
3dfed10e | 659 | fn find_commandline_library(&mut self) -> Result<Option<Library>, CrateError> { |
1a4d82fc JJ |
660 | // First, filter out all libraries that look suspicious. We only accept |
661 | // files which actually exist that have the correct naming scheme for | |
662 | // rlibs/dylibs. | |
0bf4aa26 XL |
663 | let mut rlibs = FxHashMap::default(); |
664 | let mut rmetas = FxHashMap::default(); | |
665 | let mut dylibs = FxHashMap::default(); | |
3dfed10e | 666 | for loc in &self.exact_paths { |
5869c6ff XL |
667 | if !loc.canonicalized().exists() { |
668 | return Err(CrateError::ExternLocationNotExist( | |
669 | self.crate_name, | |
670 | loc.original().clone(), | |
671 | )); | |
3dfed10e | 672 | } |
5869c6ff | 673 | let file = match loc.original().file_name().and_then(|s| s.to_str()) { |
3dfed10e XL |
674 | Some(file) => file, |
675 | None => { | |
5869c6ff XL |
676 | return Err(CrateError::ExternLocationNotFile( |
677 | self.crate_name, | |
678 | loc.original().clone(), | |
679 | )); | |
1a4d82fc | 680 | } |
3dfed10e | 681 | }; |
476ff2be | 682 | |
3dfed10e | 683 | if file.starts_with("lib") && (file.ends_with(".rlib") || file.ends_with(".rmeta")) |
29967ef6 XL |
684 | || file.starts_with(&self.target.dll_prefix) |
685 | && file.ends_with(&self.target.dll_suffix) | |
3dfed10e XL |
686 | { |
687 | // Make sure there's at most one rlib and at most one dylib. | |
688 | // Note to take care and match against the non-canonicalized name: | |
689 | // some systems save build artifacts into content-addressed stores | |
690 | // that do not preserve extensions, and then link to them using | |
691 | // e.g. symbolic links. If we canonicalize too early, we resolve | |
692 | // the symlink, the file type is lost and we might treat rlibs and | |
693 | // rmetas as dylibs. | |
5869c6ff XL |
694 | let loc_canon = loc.canonicalized().clone(); |
695 | let loc = loc.original(); | |
c34b1796 | 696 | if loc.file_name().unwrap().to_str().unwrap().ends_with(".rlib") { |
3dfed10e | 697 | rlibs.insert(loc_canon, PathKind::ExternFlag); |
476ff2be | 698 | } else if loc.file_name().unwrap().to_str().unwrap().ends_with(".rmeta") { |
3dfed10e | 699 | rmetas.insert(loc_canon, PathKind::ExternFlag); |
1a4d82fc | 700 | } else { |
3dfed10e | 701 | dylibs.insert(loc_canon, PathKind::ExternFlag); |
1a4d82fc | 702 | } |
3dfed10e | 703 | } else { |
c295e0f8 XL |
704 | self.crate_rejections |
705 | .via_filename | |
5869c6ff | 706 | .push(CrateMismatch { path: loc.original().clone(), got: String::new() }); |
1a4d82fc | 707 | } |
3dfed10e | 708 | } |
1a4d82fc | 709 | |
e74abb32 | 710 | // Extract the dylib/rlib/rmeta triple. |
3dfed10e | 711 | Ok(self.extract_lib(rlibs, rmetas, dylibs)?.map(|(_, lib)| lib)) |
223e47cc | 712 | } |
223e47cc | 713 | |
c295e0f8 | 714 | crate fn into_error(self, root: Option<CratePaths>) -> CrateError { |
3dfed10e XL |
715 | CrateError::LocatorCombined(CombinedLocatorError { |
716 | crate_name: self.crate_name, | |
c295e0f8 | 717 | root, |
3dfed10e | 718 | triple: self.triple, |
29967ef6 XL |
719 | dll_prefix: self.target.dll_prefix.clone(), |
720 | dll_suffix: self.target.dll_suffix.clone(), | |
c295e0f8 | 721 | crate_rejections: self.crate_rejections, |
3dfed10e XL |
722 | }) |
723 | } | |
223e47cc LB |
724 | } |
725 | ||
3dfed10e | 726 | fn get_metadata_section( |
dfeec247 XL |
727 | target: &Target, |
728 | flavor: CrateFlavor, | |
729 | filename: &Path, | |
730 | loader: &dyn MetadataLoader, | |
731 | ) -> Result<MetadataBlob, String> { | |
1a4d82fc JJ |
732 | if !filename.exists() { |
733 | return Err(format!("no such file: '{}'", filename.display())); | |
734 | } | |
0531ce1d | 735 | let raw_bytes: MetadataRef = match flavor { |
7cac9316 XL |
736 | CrateFlavor::Rlib => loader.get_rlib_metadata(target, filename)?, |
737 | CrateFlavor::Dylib => { | |
738 | let buf = loader.get_dylib_metadata(target, filename)?; | |
739 | // The header is uncompressed | |
740 | let header_len = METADATA_HEADER.len(); | |
741 | debug!("checking {} bytes of metadata-version stamp", header_len); | |
742 | let header = &buf[..cmp::min(header_len, buf.len())]; | |
743 | if header != METADATA_HEADER { | |
dfeec247 XL |
744 | return Err(format!( |
745 | "incompatible metadata version found: '{}'", | |
746 | filename.display() | |
747 | )); | |
1a4d82fc | 748 | } |
223e47cc | 749 | |
7cac9316 XL |
750 | // Header is okay -> inflate the actual metadata |
751 | let compressed_bytes = &buf[header_len..]; | |
752 | debug!("inflating {} bytes of compressed metadata", compressed_bytes.len()); | |
c295e0f8 XL |
753 | // Assume the decompressed data will be at least the size of the compressed data, so we |
754 | // don't have to grow the buffer as much. | |
755 | let mut inflated = Vec::with_capacity(compressed_bytes.len()); | |
1b1a35ee | 756 | match FrameDecoder::new(compressed_bytes).read_to_end(&mut inflated) { |
dfeec247 | 757 | Ok(_) => rustc_erase_owner!(OwningRef::new(inflated).map_owner_box()), |
7cac9316 XL |
758 | Err(_) => { |
759 | return Err(format!("failed to decompress metadata: {}", filename.display())); | |
223e47cc LB |
760 | } |
761 | } | |
223e47cc | 762 | } |
7cac9316 | 763 | CrateFlavor::Rmeta => { |
a1dfa0c6 | 764 | // mmap the file, because only a small fraction of it is read. |
dfeec247 XL |
765 | let file = std::fs::File::open(filename) |
766 | .map_err(|_| format!("failed to open rmeta metadata: '{}'", filename.display()))?; | |
cdc7bbd5 | 767 | let mmap = unsafe { Mmap::map(file) }; |
dfeec247 XL |
768 | let mmap = mmap |
769 | .map_err(|_| format!("failed to mmap rmeta metadata: '{}'", filename.display()))?; | |
a1dfa0c6 | 770 | |
cdc7bbd5 | 771 | rustc_erase_owner!(OwningRef::new(mmap).map_owner_box()) |
7cac9316 XL |
772 | } |
773 | }; | |
60c5eb7d | 774 | let blob = MetadataBlob::new(raw_bytes); |
7cac9316 XL |
775 | if blob.is_compatible() { |
776 | Ok(blob) | |
1a4d82fc | 777 | } else { |
7cac9316 | 778 | Err(format!("incompatible metadata version found: '{}'", filename.display())) |
223e47cc LB |
779 | } |
780 | } | |
781 | ||
e74abb32 XL |
782 | /// Look for a plugin registrar. Returns its library path and crate disambiguator. |
783 | pub fn find_plugin_registrar( | |
784 | sess: &Session, | |
785 | metadata_loader: &dyn MetadataLoader, | |
786 | span: Span, | |
787 | name: Symbol, | |
94222f64 | 788 | ) -> PathBuf { |
3dfed10e XL |
789 | match find_plugin_registrar_impl(sess, metadata_loader, name) { |
790 | Ok(res) => res, | |
cdc7bbd5 XL |
791 | // `core` is always available if we got as far as loading plugins. |
792 | Err(err) => err.report(sess, span, false), | |
3dfed10e XL |
793 | } |
794 | } | |
795 | ||
796 | fn find_plugin_registrar_impl<'a>( | |
797 | sess: &'a Session, | |
798 | metadata_loader: &dyn MetadataLoader, | |
799 | name: Symbol, | |
94222f64 | 800 | ) -> Result<PathBuf, CrateError> { |
e74abb32 | 801 | info!("find plugin registrar `{}`", name); |
60c5eb7d | 802 | let mut locator = CrateLocator::new( |
e74abb32 | 803 | sess, |
e74abb32 | 804 | metadata_loader, |
60c5eb7d XL |
805 | name, |
806 | None, // hash | |
60c5eb7d XL |
807 | None, // extra_filename |
808 | true, // is_host | |
809 | PathKind::Crate, | |
60c5eb7d | 810 | ); |
e74abb32 | 811 | |
3dfed10e XL |
812 | match locator.maybe_load_library_crate()? { |
813 | Some(library) => match library.source.dylib { | |
94222f64 | 814 | Some(dylib) => Ok(dylib.0), |
3dfed10e XL |
815 | None => Err(CrateError::NonDylibPlugin(name)), |
816 | }, | |
c295e0f8 | 817 | None => Err(locator.into_error(None)), |
e74abb32 XL |
818 | } |
819 | } | |
820 | ||
9fa01778 | 821 | /// A diagnostic function for dumping crate metadata to an output stream. |
dfeec247 XL |
822 | pub fn list_file_metadata( |
823 | target: &Target, | |
824 | path: &Path, | |
825 | metadata_loader: &dyn MetadataLoader, | |
3dfed10e XL |
826 | out: &mut dyn Write, |
827 | ) -> IoResult<()> { | |
a7813a04 | 828 | let filename = path.file_name().unwrap().to_str().unwrap(); |
c30ab7b3 SL |
829 | let flavor = if filename.ends_with(".rlib") { |
830 | CrateFlavor::Rlib | |
476ff2be SL |
831 | } else if filename.ends_with(".rmeta") { |
832 | CrateFlavor::Rmeta | |
c30ab7b3 SL |
833 | } else { |
834 | CrateFlavor::Dylib | |
835 | }; | |
e74abb32 | 836 | match get_metadata_section(target, flavor, path, metadata_loader) { |
9e0c209e | 837 | Ok(metadata) => metadata.list_crate_metadata(out), |
c30ab7b3 | 838 | Err(msg) => write!(out, "{}\n", msg), |
223e47cc LB |
839 | } |
840 | } | |
3dfed10e XL |
841 | |
842 | // ------------------------------------------ Error reporting ------------------------------------- | |
843 | ||
844 | #[derive(Clone)] | |
845 | struct CrateMismatch { | |
846 | path: PathBuf, | |
847 | got: String, | |
848 | } | |
849 | ||
c295e0f8 XL |
850 | #[derive(Clone, Default)] |
851 | struct CrateRejections { | |
852 | via_hash: Vec<CrateMismatch>, | |
853 | via_triple: Vec<CrateMismatch>, | |
854 | via_kind: Vec<CrateMismatch>, | |
855 | via_version: Vec<CrateMismatch>, | |
856 | via_filename: Vec<CrateMismatch>, | |
857 | } | |
858 | ||
3dfed10e XL |
859 | /// Candidate rejection reasons collected during crate search. |
860 | /// If no candidate is accepted, then these reasons are presented to the user, | |
861 | /// otherwise they are ignored. | |
862 | crate struct CombinedLocatorError { | |
863 | crate_name: Symbol, | |
864 | root: Option<CratePaths>, | |
865 | triple: TargetTriple, | |
866 | dll_prefix: String, | |
867 | dll_suffix: String, | |
c295e0f8 | 868 | crate_rejections: CrateRejections, |
3dfed10e XL |
869 | } |
870 | ||
871 | crate enum CrateError { | |
872 | NonAsciiName(Symbol), | |
873 | ExternLocationNotExist(Symbol, PathBuf), | |
874 | ExternLocationNotFile(Symbol, PathBuf), | |
875 | MultipleCandidates(Symbol, CrateFlavor, Vec<PathBuf>), | |
876 | MultipleMatchingCrates(Symbol, FxHashMap<Svh, Library>), | |
877 | SymbolConflictsCurrent(Symbol), | |
878 | SymbolConflictsOthers(Symbol), | |
6a06907d | 879 | StableCrateIdCollision(Symbol, Symbol), |
3dfed10e XL |
880 | DlOpen(String), |
881 | DlSym(String), | |
882 | LocatorCombined(CombinedLocatorError), | |
883 | NonDylibPlugin(Symbol), | |
884 | } | |
885 | ||
886 | impl CrateError { | |
cdc7bbd5 | 887 | crate fn report(self, sess: &Session, span: Span, missing_core: bool) -> ! { |
3dfed10e XL |
888 | let mut err = match self { |
889 | CrateError::NonAsciiName(crate_name) => sess.struct_span_err( | |
890 | span, | |
891 | &format!("cannot load a crate with a non-ascii name `{}`", crate_name), | |
892 | ), | |
893 | CrateError::ExternLocationNotExist(crate_name, loc) => sess.struct_span_err( | |
894 | span, | |
895 | &format!("extern location for {} does not exist: {}", crate_name, loc.display()), | |
896 | ), | |
897 | CrateError::ExternLocationNotFile(crate_name, loc) => sess.struct_span_err( | |
898 | span, | |
899 | &format!("extern location for {} is not a file: {}", crate_name, loc.display()), | |
900 | ), | |
901 | CrateError::MultipleCandidates(crate_name, flavor, candidates) => { | |
902 | let mut err = struct_span_err!( | |
903 | sess, | |
904 | span, | |
905 | E0465, | |
906 | "multiple {} candidates for `{}` found", | |
907 | flavor, | |
908 | crate_name, | |
909 | ); | |
910 | for (i, candidate) in candidates.iter().enumerate() { | |
911 | err.span_note(span, &format!("candidate #{}: {}", i + 1, candidate.display())); | |
912 | } | |
913 | err | |
914 | } | |
915 | CrateError::MultipleMatchingCrates(crate_name, libraries) => { | |
916 | let mut err = struct_span_err!( | |
917 | sess, | |
918 | span, | |
919 | E0464, | |
920 | "multiple matching crates for `{}`", | |
921 | crate_name | |
922 | ); | |
c295e0f8 XL |
923 | let mut libraries: Vec<_> = libraries.into_values().collect(); |
924 | // Make ordering of candidates deterministic. | |
925 | // This has to `clone()` to work around lifetime restrictions with `sort_by_key()`. | |
926 | // `sort_by()` could be used instead, but this is in the error path, | |
927 | // so the performance shouldn't matter. | |
928 | libraries.sort_by_cached_key(|lib| lib.source.paths().next().unwrap().clone()); | |
3dfed10e XL |
929 | let candidates = libraries |
930 | .iter() | |
c295e0f8 | 931 | .map(|lib| { |
3dfed10e | 932 | let crate_name = &lib.metadata.get_root().name().as_str(); |
c295e0f8 XL |
933 | let mut paths = lib.source.paths(); |
934 | ||
935 | // This `unwrap()` should be okay because there has to be at least one | |
936 | // source file. `CrateSource`'s docs confirm that too. | |
937 | let mut s = format!( | |
938 | "\ncrate `{}`: {}", | |
939 | crate_name, | |
940 | paths.next().unwrap().display() | |
941 | ); | |
942 | let padding = 8 + crate_name.len(); | |
943 | for path in paths { | |
944 | write!(s, "\n{:>padding$}", path.display(), padding = padding).unwrap(); | |
3dfed10e | 945 | } |
c295e0f8 | 946 | s |
3dfed10e XL |
947 | }) |
948 | .collect::<String>(); | |
949 | err.note(&format!("candidates:{}", candidates)); | |
950 | err | |
951 | } | |
952 | CrateError::SymbolConflictsCurrent(root_name) => struct_span_err!( | |
953 | sess, | |
954 | span, | |
955 | E0519, | |
956 | "the current crate is indistinguishable from one of its dependencies: it has the \ | |
957 | same crate-name `{}` and was compiled with the same `-C metadata` arguments. \ | |
958 | This will result in symbol conflicts between the two.", | |
959 | root_name, | |
960 | ), | |
961 | CrateError::SymbolConflictsOthers(root_name) => struct_span_err!( | |
962 | sess, | |
963 | span, | |
964 | E0523, | |
965 | "found two different crates with name `{}` that are not distinguished by differing \ | |
966 | `-C metadata`. This will result in symbol conflicts between the two.", | |
967 | root_name, | |
968 | ), | |
6a06907d XL |
969 | CrateError::StableCrateIdCollision(crate_name0, crate_name1) => { |
970 | let msg = format!( | |
971 | "found crates (`{}` and `{}`) with colliding StableCrateId values.", | |
972 | crate_name0, crate_name1 | |
973 | ); | |
974 | sess.struct_span_err(span, &msg) | |
975 | } | |
3dfed10e XL |
976 | CrateError::DlOpen(s) | CrateError::DlSym(s) => sess.struct_span_err(span, &s), |
977 | CrateError::LocatorCombined(locator) => { | |
978 | let crate_name = locator.crate_name; | |
979 | let add = match &locator.root { | |
980 | None => String::new(), | |
981 | Some(r) => format!(" which `{}` depends on", r.name), | |
982 | }; | |
983 | let mut msg = "the following crate versions were found:".to_string(); | |
c295e0f8 | 984 | let mut err = if !locator.crate_rejections.via_hash.is_empty() { |
3dfed10e XL |
985 | let mut err = struct_span_err!( |
986 | sess, | |
987 | span, | |
988 | E0460, | |
989 | "found possibly newer version of crate `{}`{}", | |
990 | crate_name, | |
991 | add, | |
992 | ); | |
993 | err.note("perhaps that crate needs to be recompiled?"); | |
c295e0f8 | 994 | let mismatches = locator.crate_rejections.via_hash.iter(); |
3dfed10e XL |
995 | for CrateMismatch { path, .. } in mismatches { |
996 | msg.push_str(&format!("\ncrate `{}`: {}", crate_name, path.display())); | |
997 | } | |
998 | if let Some(r) = locator.root { | |
999 | for path in r.source.paths() { | |
1000 | msg.push_str(&format!("\ncrate `{}`: {}", r.name, path.display())); | |
1001 | } | |
1002 | } | |
1003 | err.note(&msg); | |
1004 | err | |
c295e0f8 | 1005 | } else if !locator.crate_rejections.via_triple.is_empty() { |
3dfed10e XL |
1006 | let mut err = struct_span_err!( |
1007 | sess, | |
1008 | span, | |
1009 | E0461, | |
1010 | "couldn't find crate `{}` with expected target triple {}{}", | |
1011 | crate_name, | |
1012 | locator.triple, | |
1013 | add, | |
1014 | ); | |
c295e0f8 | 1015 | let mismatches = locator.crate_rejections.via_triple.iter(); |
3dfed10e XL |
1016 | for CrateMismatch { path, got } in mismatches { |
1017 | msg.push_str(&format!( | |
1018 | "\ncrate `{}`, target triple {}: {}", | |
1019 | crate_name, | |
1020 | got, | |
1021 | path.display(), | |
1022 | )); | |
1023 | } | |
1024 | err.note(&msg); | |
1025 | err | |
c295e0f8 | 1026 | } else if !locator.crate_rejections.via_kind.is_empty() { |
3dfed10e XL |
1027 | let mut err = struct_span_err!( |
1028 | sess, | |
1029 | span, | |
1030 | E0462, | |
1031 | "found staticlib `{}` instead of rlib or dylib{}", | |
1032 | crate_name, | |
1033 | add, | |
1034 | ); | |
1035 | err.help("please recompile that crate using --crate-type lib"); | |
c295e0f8 | 1036 | let mismatches = locator.crate_rejections.via_kind.iter(); |
3dfed10e XL |
1037 | for CrateMismatch { path, .. } in mismatches { |
1038 | msg.push_str(&format!("\ncrate `{}`: {}", crate_name, path.display())); | |
1039 | } | |
1040 | err.note(&msg); | |
1041 | err | |
c295e0f8 | 1042 | } else if !locator.crate_rejections.via_version.is_empty() { |
3dfed10e XL |
1043 | let mut err = struct_span_err!( |
1044 | sess, | |
1045 | span, | |
1046 | E0514, | |
1047 | "found crate `{}` compiled by an incompatible version of rustc{}", | |
1048 | crate_name, | |
1049 | add, | |
1050 | ); | |
1051 | err.help(&format!( | |
c295e0f8 XL |
1052 | "please recompile that crate using this compiler ({}) \ |
1053 | (consider running `cargo clean` first)", | |
3dfed10e XL |
1054 | rustc_version(), |
1055 | )); | |
c295e0f8 | 1056 | let mismatches = locator.crate_rejections.via_version.iter(); |
3dfed10e XL |
1057 | for CrateMismatch { path, got } in mismatches { |
1058 | msg.push_str(&format!( | |
1059 | "\ncrate `{}` compiled by {}: {}", | |
1060 | crate_name, | |
1061 | got, | |
1062 | path.display(), | |
1063 | )); | |
1064 | } | |
1065 | err.note(&msg); | |
1066 | err | |
1067 | } else { | |
1068 | let mut err = struct_span_err!( | |
1069 | sess, | |
1070 | span, | |
1071 | E0463, | |
1072 | "can't find crate for `{}`{}", | |
1073 | crate_name, | |
1074 | add, | |
1075 | ); | |
1076 | ||
1077 | if (crate_name == sym::std || crate_name == sym::core) | |
1078 | && locator.triple != TargetTriple::from_triple(config::host_triple()) | |
1079 | { | |
cdc7bbd5 XL |
1080 | if missing_core { |
1081 | err.note(&format!( | |
1082 | "the `{}` target may not be installed", | |
1083 | locator.triple | |
1084 | )); | |
1085 | } else { | |
1086 | err.note(&format!( | |
1087 | "the `{}` target may not support the standard library", | |
1088 | locator.triple | |
1089 | )); | |
1090 | } | |
94222f64 XL |
1091 | // NOTE: this suggests using rustup, even though the user may not have it installed. |
1092 | // That's because they could choose to install it; or this may give them a hint which | |
1093 | // target they need to install from their distro. | |
1094 | if missing_core { | |
cdc7bbd5 XL |
1095 | err.help(&format!( |
1096 | "consider downloading the target with `rustup target add {}`", | |
1097 | locator.triple | |
1098 | )); | |
1099 | } | |
1100 | // Suggest using #![no_std]. #[no_core] is unstable and not really supported anyway. | |
1101 | // NOTE: this is a dummy span if `extern crate std` was injected by the compiler. | |
1102 | // If it's not a dummy, that means someone added `extern crate std` explicitly and `#![no_std]` won't help. | |
1103 | if !missing_core && span.is_dummy() { | |
1104 | let current_crate = | |
1105 | sess.opts.crate_name.as_deref().unwrap_or("<unknown>"); | |
1106 | err.note(&format!( | |
1107 | "`std` is required by `{}` because it does not declare `#![no_std]`", | |
1108 | current_crate | |
1109 | )); | |
1110 | } | |
94222f64 | 1111 | if sess.is_nightly_build() { |
cdc7bbd5 XL |
1112 | err.help("consider building the standard library from source with `cargo build -Zbuild-std`"); |
1113 | } | |
94222f64 XL |
1114 | } else if crate_name |
1115 | == Symbol::intern(&sess.opts.debugging_opts.profiler_runtime) | |
136023e0 | 1116 | { |
3dfed10e | 1117 | err.note(&"the compiler may have been built without the profiler runtime"); |
c295e0f8 XL |
1118 | } else if crate_name.as_str().starts_with("rustc_") { |
1119 | err.help( | |
1120 | "maybe you need to install the missing components with: \ | |
1121 | `rustup component add rust-src rustc-dev llvm-tools-preview`", | |
1122 | ); | |
3dfed10e XL |
1123 | } |
1124 | err.span_label(span, "can't find crate"); | |
1125 | err | |
1126 | }; | |
1127 | ||
c295e0f8 XL |
1128 | if !locator.crate_rejections.via_filename.is_empty() { |
1129 | let mismatches = locator.crate_rejections.via_filename.iter(); | |
3dfed10e XL |
1130 | for CrateMismatch { path, .. } in mismatches { |
1131 | err.note(&format!( | |
1132 | "extern location for {} is of an unknown type: {}", | |
1133 | crate_name, | |
1134 | path.display(), | |
1135 | )) | |
1136 | .help(&format!( | |
1137 | "file name should be lib*.rlib or {}*.{}", | |
1138 | locator.dll_prefix, locator.dll_suffix | |
1139 | )); | |
1140 | } | |
1141 | } | |
1142 | err | |
1143 | } | |
1144 | CrateError::NonDylibPlugin(crate_name) => struct_span_err!( | |
1145 | sess, | |
1146 | span, | |
1147 | E0457, | |
1148 | "plugin `{}` only found in rlib format, but must be available in dylib format", | |
1149 | crate_name, | |
1150 | ), | |
1151 | }; | |
1152 | ||
1153 | err.emit(); | |
1154 | sess.abort_if_errors(); | |
1155 | unreachable!(); | |
1156 | } | |
1157 | } |