]> git.lizzy.rs Git - rust.git/blob - compiler/rustc_interface/src/passes.rs
Rollup merge of #106946 - dtolnay:hashlinecolumn, r=m-ou-se
[rust.git] / compiler / rustc_interface / src / passes.rs
1 use crate::errors::{
2     CantEmitMIR, EmojiIdentifier, ErrorWritingDependencies, FerrisIdentifier,
3     GeneratedFileConflictsWithDirectory, InputFileWouldBeOverWritten, MixedBinCrate,
4     MixedProcMacroCrate, OutDirError, ProcMacroCratePanicAbort, ProcMacroDocWithoutArg,
5     TempsDirError,
6 };
7 use crate::interface::{Compiler, Result};
8 use crate::proc_macro_decls;
9 use crate::util;
10
11 use ast::CRATE_NODE_ID;
12 use rustc_ast::{self as ast, visit};
13 use rustc_borrowck as mir_borrowck;
14 use rustc_codegen_ssa::traits::CodegenBackend;
15 use rustc_data_structures::parallel;
16 use rustc_data_structures::sync::{Lrc, OnceCell, WorkerLocal};
17 use rustc_errors::{ErrorGuaranteed, PResult};
18 use rustc_expand::base::{ExtCtxt, LintStoreExpand, ResolverExpand};
19 use rustc_hir::def_id::StableCrateId;
20 use rustc_lint::{BufferedEarlyLint, EarlyCheckNode, LintStore};
21 use rustc_metadata::creader::CStore;
22 use rustc_middle::arena::Arena;
23 use rustc_middle::dep_graph::DepGraph;
24 use rustc_middle::ty::query::{ExternProviders, Providers};
25 use rustc_middle::ty::{self, GlobalCtxt, RegisteredTools, TyCtxt};
26 use rustc_mir_build as mir_build;
27 use rustc_parse::{parse_crate_from_file, parse_crate_from_source_str, validate_attr};
28 use rustc_passes::{self, hir_stats, layout_test};
29 use rustc_plugin_impl as plugin;
30 use rustc_query_impl::{OnDiskCache, Queries as TcxQueries};
31 use rustc_resolve::{Resolver, ResolverArenas};
32 use rustc_session::config::{CrateType, Input, OutputFilenames, OutputType};
33 use rustc_session::cstore::{MetadataLoader, MetadataLoaderDyn, Untracked};
34 use rustc_session::output::filename_for_input;
35 use rustc_session::search_paths::PathKind;
36 use rustc_session::{Limit, Session};
37 use rustc_span::symbol::{sym, Symbol};
38 use rustc_span::FileName;
39 use rustc_target::spec::PanicStrategy;
40 use rustc_trait_selection::traits;
41
42 use std::any::Any;
43 use std::cell::RefCell;
44 use std::ffi::OsString;
45 use std::io::{self, BufWriter, Write};
46 use std::marker::PhantomPinned;
47 use std::path::{Path, PathBuf};
48 use std::pin::Pin;
49 use std::rc::Rc;
50 use std::sync::LazyLock;
51 use std::{env, fs, iter};
52
53 pub fn parse<'a>(sess: &'a Session) -> PResult<'a, ast::Crate> {
54     let krate = sess.time("parse_crate", || match &sess.io.input {
55         Input::File(file) => parse_crate_from_file(file, &sess.parse_sess),
56         Input::Str { input, name } => {
57             parse_crate_from_source_str(name.clone(), input.clone(), &sess.parse_sess)
58         }
59     })?;
60
61     if sess.opts.unstable_opts.input_stats {
62         eprintln!("Lines of code:             {}", sess.source_map().count_lines());
63         eprintln!("Pre-expansion node count:  {}", count_nodes(&krate));
64     }
65
66     if let Some(ref s) = sess.opts.unstable_opts.show_span {
67         rustc_ast_passes::show_span::run(sess.diagnostic(), s, &krate);
68     }
69
70     if sess.opts.unstable_opts.hir_stats {
71         hir_stats::print_ast_stats(&krate, "PRE EXPANSION AST STATS", "ast-stats-1");
72     }
73
74     Ok(krate)
75 }
76
77 fn count_nodes(krate: &ast::Crate) -> usize {
78     let mut counter = rustc_ast_passes::node_count::NodeCounter::new();
79     visit::walk_crate(&mut counter, krate);
80     counter.count
81 }
82
83 pub use boxed_resolver::BoxedResolver;
84 mod boxed_resolver {
85     use super::*;
86
87     pub struct BoxedResolver(Pin<Box<BoxedResolverInner>>);
88
89     struct BoxedResolverInner {
90         session: Lrc<Session>,
91         resolver_arenas: Option<ResolverArenas<'static>>,
92         resolver: Option<Resolver<'static>>,
93         _pin: PhantomPinned,
94     }
95
96     // Note: Drop order is important to prevent dangling references. Resolver must be dropped first,
97     // then resolver_arenas and session.
98     impl Drop for BoxedResolverInner {
99         fn drop(&mut self) {
100             self.resolver.take();
101             self.resolver_arenas.take();
102         }
103     }
104
105     impl BoxedResolver {
106         pub(super) fn new(
107             session: Lrc<Session>,
108             make_resolver: impl for<'a> FnOnce(&'a Session, &'a ResolverArenas<'a>) -> Resolver<'a>,
109         ) -> BoxedResolver {
110             let mut boxed_resolver = Box::new(BoxedResolverInner {
111                 session,
112                 resolver_arenas: Some(Resolver::arenas()),
113                 resolver: None,
114                 _pin: PhantomPinned,
115             });
116             // SAFETY: `make_resolver` takes a resolver arena with an arbitrary lifetime and
117             // returns a resolver with the same lifetime as the arena. We ensure that the arena
118             // outlives the resolver in the drop impl and elsewhere so these transmutes are sound.
119             unsafe {
120                 let resolver = make_resolver(
121                     std::mem::transmute::<&Session, &Session>(&boxed_resolver.session),
122                     std::mem::transmute::<&ResolverArenas<'_>, &ResolverArenas<'_>>(
123                         boxed_resolver.resolver_arenas.as_ref().unwrap(),
124                     ),
125                 );
126                 boxed_resolver.resolver = Some(resolver);
127                 BoxedResolver(Pin::new_unchecked(boxed_resolver))
128             }
129         }
130
131         pub fn access<F: for<'a> FnOnce(&mut Resolver<'a>) -> R, R>(&mut self, f: F) -> R {
132             // SAFETY: The resolver doesn't need to be pinned.
133             let mut resolver = unsafe {
134                 self.0.as_mut().map_unchecked_mut(|boxed_resolver| &mut boxed_resolver.resolver)
135             };
136             f((&mut *resolver).as_mut().unwrap())
137         }
138
139         pub fn to_resolver_outputs(resolver: Rc<RefCell<BoxedResolver>>) -> ty::ResolverOutputs {
140             match Rc::try_unwrap(resolver) {
141                 Ok(resolver) => {
142                     let mut resolver = resolver.into_inner();
143                     // SAFETY: The resolver doesn't need to be pinned.
144                     let mut resolver = unsafe {
145                         resolver
146                             .0
147                             .as_mut()
148                             .map_unchecked_mut(|boxed_resolver| &mut boxed_resolver.resolver)
149                     };
150                     resolver.take().unwrap().into_outputs()
151                 }
152                 Err(resolver) => resolver.borrow_mut().access(|resolver| resolver.clone_outputs()),
153             }
154         }
155     }
156 }
157
158 pub fn create_resolver(
159     sess: Lrc<Session>,
160     metadata_loader: Box<MetadataLoaderDyn>,
161     krate: &ast::Crate,
162     crate_name: Symbol,
163 ) -> BoxedResolver {
164     trace!("create_resolver");
165     BoxedResolver::new(sess, move |sess, resolver_arenas| {
166         Resolver::new(sess, krate, crate_name, metadata_loader, resolver_arenas)
167     })
168 }
169
170 pub fn register_plugins<'a>(
171     sess: &'a Session,
172     metadata_loader: &'a dyn MetadataLoader,
173     register_lints: impl Fn(&Session, &mut LintStore),
174     mut krate: ast::Crate,
175     crate_name: Symbol,
176 ) -> Result<(ast::Crate, LintStore)> {
177     krate = sess.time("attributes_injection", || {
178         rustc_builtin_macros::cmdline_attrs::inject(
179             krate,
180             &sess.parse_sess,
181             &sess.opts.unstable_opts.crate_attr,
182         )
183     });
184
185     let (krate, features) = rustc_expand::config::features(sess, krate, CRATE_NODE_ID);
186     // these need to be set "early" so that expansion sees `quote` if enabled.
187     sess.init_features(features);
188
189     let crate_types = util::collect_crate_types(sess, &krate.attrs);
190     sess.init_crate_types(crate_types);
191
192     let stable_crate_id = StableCrateId::new(
193         crate_name,
194         sess.crate_types().contains(&CrateType::Executable),
195         sess.opts.cg.metadata.clone(),
196     );
197     sess.stable_crate_id.set(stable_crate_id).expect("not yet initialized");
198     rustc_incremental::prepare_session_directory(sess, crate_name, stable_crate_id)?;
199
200     if sess.opts.incremental.is_some() {
201         sess.time("incr_comp_garbage_collect_session_directories", || {
202             if let Err(e) = rustc_incremental::garbage_collect_session_directories(sess) {
203                 warn!(
204                     "Error while trying to garbage collect incremental \
205                      compilation cache directory: {}",
206                     e
207                 );
208             }
209         });
210     }
211
212     let mut lint_store = rustc_lint::new_lint_store(sess.enable_internal_lints());
213     register_lints(sess, &mut lint_store);
214
215     let registrars =
216         sess.time("plugin_loading", || plugin::load::load_plugins(sess, metadata_loader, &krate));
217     sess.time("plugin_registration", || {
218         let mut registry = plugin::Registry { lint_store: &mut lint_store };
219         for registrar in registrars {
220             registrar(&mut registry);
221         }
222     });
223
224     Ok((krate, lint_store))
225 }
226
227 fn pre_expansion_lint<'a>(
228     sess: &Session,
229     lint_store: &LintStore,
230     registered_tools: &RegisteredTools,
231     check_node: impl EarlyCheckNode<'a>,
232     node_name: Symbol,
233 ) {
234     sess.prof.generic_activity_with_arg("pre_AST_expansion_lint_checks", node_name.as_str()).run(
235         || {
236             rustc_lint::check_ast_node(
237                 sess,
238                 true,
239                 lint_store,
240                 registered_tools,
241                 None,
242                 rustc_lint::BuiltinCombinedPreExpansionLintPass::new(),
243                 check_node,
244             );
245         },
246     );
247 }
248
249 // Cannot implement directly for `LintStore` due to trait coherence.
250 struct LintStoreExpandImpl<'a>(&'a LintStore);
251
252 impl LintStoreExpand for LintStoreExpandImpl<'_> {
253     fn pre_expansion_lint(
254         &self,
255         sess: &Session,
256         registered_tools: &RegisteredTools,
257         node_id: ast::NodeId,
258         attrs: &[ast::Attribute],
259         items: &[rustc_ast::ptr::P<ast::Item>],
260         name: Symbol,
261     ) {
262         pre_expansion_lint(sess, self.0, registered_tools, (node_id, attrs, items), name);
263     }
264 }
265
266 /// Runs the "early phases" of the compiler: initial `cfg` processing, loading compiler plugins,
267 /// syntax expansion, secondary `cfg` expansion, synthesis of a test
268 /// harness if one is to be provided, injection of a dependency on the
269 /// standard library and prelude, and name resolution.
270 pub fn configure_and_expand(
271     sess: &Session,
272     lint_store: &LintStore,
273     mut krate: ast::Crate,
274     crate_name: Symbol,
275     resolver: &mut Resolver<'_>,
276 ) -> Result<ast::Crate> {
277     trace!("configure_and_expand");
278     pre_expansion_lint(sess, lint_store, resolver.registered_tools(), &krate, crate_name);
279     rustc_builtin_macros::register_builtin_macros(resolver);
280
281     krate = sess.time("crate_injection", || {
282         rustc_builtin_macros::standard_library_imports::inject(krate, resolver, sess)
283     });
284
285     util::check_attr_crate_type(sess, &krate.attrs, &mut resolver.lint_buffer());
286
287     // Expand all macros
288     krate = sess.time("macro_expand_crate", || {
289         // Windows dlls do not have rpaths, so they don't know how to find their
290         // dependencies. It's up to us to tell the system where to find all the
291         // dependent dlls. Note that this uses cfg!(windows) as opposed to
292         // targ_cfg because syntax extensions are always loaded for the host
293         // compiler, not for the target.
294         //
295         // This is somewhat of an inherently racy operation, however, as
296         // multiple threads calling this function could possibly continue
297         // extending PATH far beyond what it should. To solve this for now we
298         // just don't add any new elements to PATH which are already there
299         // within PATH. This is basically a targeted fix at #17360 for rustdoc
300         // which runs rustc in parallel but has been seen (#33844) to cause
301         // problems with PATH becoming too long.
302         let mut old_path = OsString::new();
303         if cfg!(windows) {
304             old_path = env::var_os("PATH").unwrap_or(old_path);
305             let mut new_path = sess.host_filesearch(PathKind::All).search_path_dirs();
306             for path in env::split_paths(&old_path) {
307                 if !new_path.contains(&path) {
308                     new_path.push(path);
309                 }
310             }
311             env::set_var(
312                 "PATH",
313                 &env::join_paths(
314                     new_path.iter().filter(|p| env::join_paths(iter::once(p)).is_ok()),
315                 )
316                 .unwrap(),
317             );
318         }
319
320         // Create the config for macro expansion
321         let features = sess.features_untracked();
322         let recursion_limit = get_recursion_limit(&krate.attrs, sess);
323         let cfg = rustc_expand::expand::ExpansionConfig {
324             features: Some(features),
325             recursion_limit,
326             trace_mac: sess.opts.unstable_opts.trace_macros,
327             should_test: sess.opts.test,
328             span_debug: sess.opts.unstable_opts.span_debug,
329             proc_macro_backtrace: sess.opts.unstable_opts.proc_macro_backtrace,
330             ..rustc_expand::expand::ExpansionConfig::default(crate_name.to_string())
331         };
332
333         let lint_store = LintStoreExpandImpl(lint_store);
334         let mut ecx = ExtCtxt::new(sess, cfg, resolver, Some(&lint_store));
335         // Expand macros now!
336         let krate = sess.time("expand_crate", || ecx.monotonic_expander().expand_crate(krate));
337
338         // The rest is error reporting
339
340         sess.parse_sess.buffered_lints.with_lock(|buffered_lints: &mut Vec<BufferedEarlyLint>| {
341             buffered_lints.append(&mut ecx.buffered_early_lint);
342         });
343
344         sess.time("check_unused_macros", || {
345             ecx.check_unused_macros();
346         });
347
348         let recursion_limit_hit = ecx.reduced_recursion_limit.is_some();
349
350         if cfg!(windows) {
351             env::set_var("PATH", &old_path);
352         }
353
354         if recursion_limit_hit {
355             // If we hit a recursion limit, exit early to avoid later passes getting overwhelmed
356             // with a large AST
357             Err(ErrorGuaranteed::unchecked_claim_error_was_emitted())
358         } else {
359             Ok(krate)
360         }
361     })?;
362
363     sess.time("maybe_building_test_harness", || {
364         rustc_builtin_macros::test_harness::inject(sess, resolver, &mut krate)
365     });
366
367     let has_proc_macro_decls = sess.time("AST_validation", || {
368         rustc_ast_passes::ast_validation::check_crate(sess, &krate, resolver.lint_buffer())
369     });
370
371     let crate_types = sess.crate_types();
372     let is_executable_crate = crate_types.contains(&CrateType::Executable);
373     let is_proc_macro_crate = crate_types.contains(&CrateType::ProcMacro);
374
375     if crate_types.len() > 1 {
376         if is_executable_crate {
377             sess.emit_err(MixedBinCrate);
378         }
379         if is_proc_macro_crate {
380             sess.emit_err(MixedProcMacroCrate);
381         }
382     }
383
384     if is_proc_macro_crate && sess.panic_strategy() == PanicStrategy::Abort {
385         sess.emit_warning(ProcMacroCratePanicAbort);
386     }
387
388     // For backwards compatibility, we don't try to run proc macro injection
389     // if rustdoc is run on a proc macro crate without '--crate-type proc-macro' being
390     // specified. This should only affect users who manually invoke 'rustdoc', as
391     // 'cargo doc' will automatically pass the proper '--crate-type' flags.
392     // However, we do emit a warning, to let such users know that they should
393     // start passing '--crate-type proc-macro'
394     if has_proc_macro_decls && sess.opts.actually_rustdoc && !is_proc_macro_crate {
395         sess.emit_warning(ProcMacroDocWithoutArg);
396     } else {
397         krate = sess.time("maybe_create_a_macro_crate", || {
398             let is_test_crate = sess.opts.test;
399             rustc_builtin_macros::proc_macro_harness::inject(
400                 sess,
401                 resolver,
402                 krate,
403                 is_proc_macro_crate,
404                 has_proc_macro_decls,
405                 is_test_crate,
406                 sess.diagnostic(),
407             )
408         });
409     }
410
411     // Done with macro expansion!
412
413     if sess.opts.unstable_opts.input_stats {
414         eprintln!("Post-expansion node count: {}", count_nodes(&krate));
415     }
416
417     if sess.opts.unstable_opts.hir_stats {
418         hir_stats::print_ast_stats(&krate, "POST EXPANSION AST STATS", "ast-stats-2");
419     }
420
421     resolver.resolve_crate(&krate);
422
423     // Needs to go *after* expansion to be able to check the results of macro expansion.
424     sess.time("complete_gated_feature_checking", || {
425         rustc_ast_passes::feature_gate::check_crate(&krate, sess);
426     });
427
428     // Add all buffered lints from the `ParseSess` to the `Session`.
429     sess.parse_sess.buffered_lints.with_lock(|buffered_lints| {
430         info!("{} parse sess buffered_lints", buffered_lints.len());
431         for early_lint in buffered_lints.drain(..) {
432             resolver.lint_buffer().add_early_lint(early_lint);
433         }
434     });
435
436     // Gate identifiers containing invalid Unicode codepoints that were recovered during lexing.
437     sess.parse_sess.bad_unicode_identifiers.with_lock(|identifiers| {
438         let mut identifiers: Vec<_> = identifiers.drain().collect();
439         identifiers.sort_by_key(|&(key, _)| key);
440         for (ident, mut spans) in identifiers.into_iter() {
441             spans.sort();
442             if ident == sym::ferris {
443                 let first_span = spans[0];
444                 sess.emit_err(FerrisIdentifier { spans, first_span });
445             } else {
446                 sess.emit_err(EmojiIdentifier { spans, ident });
447             }
448         }
449     });
450
451     sess.time("early_lint_checks", || {
452         let lint_buffer = Some(std::mem::take(resolver.lint_buffer()));
453         rustc_lint::check_ast_node(
454             sess,
455             false,
456             lint_store,
457             resolver.registered_tools(),
458             lint_buffer,
459             rustc_lint::BuiltinCombinedEarlyLintPass::new(),
460             &krate,
461         )
462     });
463
464     Ok(krate)
465 }
466
467 // Returns all the paths that correspond to generated files.
468 fn generated_output_paths(
469     sess: &Session,
470     outputs: &OutputFilenames,
471     exact_name: bool,
472     crate_name: Symbol,
473 ) -> Vec<PathBuf> {
474     let mut out_filenames = Vec::new();
475     for output_type in sess.opts.output_types.keys() {
476         let file = outputs.path(*output_type);
477         match *output_type {
478             // If the filename has been overridden using `-o`, it will not be modified
479             // by appending `.rlib`, `.exe`, etc., so we can skip this transformation.
480             OutputType::Exe if !exact_name => {
481                 for crate_type in sess.crate_types().iter() {
482                     let p = filename_for_input(sess, *crate_type, crate_name, outputs);
483                     out_filenames.push(p);
484                 }
485             }
486             OutputType::DepInfo if sess.opts.unstable_opts.dep_info_omit_d_target => {
487                 // Don't add the dep-info output when omitting it from dep-info targets
488             }
489             _ => {
490                 out_filenames.push(file);
491             }
492         }
493     }
494     out_filenames
495 }
496
497 // Runs `f` on every output file path and returns the first non-None result, or None if `f`
498 // returns None for every file path.
499 fn check_output<F, T>(output_paths: &[PathBuf], f: F) -> Option<T>
500 where
501     F: Fn(&PathBuf) -> Option<T>,
502 {
503     for output_path in output_paths {
504         if let Some(result) = f(output_path) {
505             return Some(result);
506         }
507     }
508     None
509 }
510
511 fn output_contains_path(output_paths: &[PathBuf], input_path: &Path) -> bool {
512     let input_path = input_path.canonicalize().ok();
513     if input_path.is_none() {
514         return false;
515     }
516     let check = |output_path: &PathBuf| {
517         if output_path.canonicalize().ok() == input_path { Some(()) } else { None }
518     };
519     check_output(output_paths, check).is_some()
520 }
521
522 fn output_conflicts_with_dir(output_paths: &[PathBuf]) -> Option<PathBuf> {
523     let check = |output_path: &PathBuf| output_path.is_dir().then(|| output_path.clone());
524     check_output(output_paths, check)
525 }
526
527 fn escape_dep_filename(filename: &str) -> String {
528     // Apparently clang and gcc *only* escape spaces:
529     // https://llvm.org/klaus/clang/commit/9d50634cfc268ecc9a7250226dd5ca0e945240d4
530     filename.replace(' ', "\\ ")
531 }
532
533 // Makefile comments only need escaping newlines and `\`.
534 // The result can be unescaped by anything that can unescape `escape_default` and friends.
535 fn escape_dep_env(symbol: Symbol) -> String {
536     let s = symbol.as_str();
537     let mut escaped = String::with_capacity(s.len());
538     for c in s.chars() {
539         match c {
540             '\n' => escaped.push_str(r"\n"),
541             '\r' => escaped.push_str(r"\r"),
542             '\\' => escaped.push_str(r"\\"),
543             _ => escaped.push(c),
544         }
545     }
546     escaped
547 }
548
549 fn write_out_deps(
550     sess: &Session,
551     boxed_resolver: &RefCell<BoxedResolver>,
552     outputs: &OutputFilenames,
553     out_filenames: &[PathBuf],
554 ) {
555     // Write out dependency rules to the dep-info file if requested
556     if !sess.opts.output_types.contains_key(&OutputType::DepInfo) {
557         return;
558     }
559     let deps_filename = outputs.path(OutputType::DepInfo);
560
561     let result: io::Result<()> = try {
562         // Build a list of files used to compile the output and
563         // write Makefile-compatible dependency rules
564         let mut files: Vec<String> = sess
565             .source_map()
566             .files()
567             .iter()
568             .filter(|fmap| fmap.is_real_file())
569             .filter(|fmap| !fmap.is_imported())
570             .map(|fmap| escape_dep_filename(&fmap.name.prefer_local().to_string()))
571             .collect();
572
573         // Account for explicitly marked-to-track files
574         // (e.g. accessed in proc macros).
575         let file_depinfo = sess.parse_sess.file_depinfo.borrow();
576
577         let normalize_path = |path: PathBuf| {
578             let file = FileName::from(path);
579             escape_dep_filename(&file.prefer_local().to_string())
580         };
581
582         let extra_tracked_files =
583             file_depinfo.iter().map(|path_sym| normalize_path(PathBuf::from(path_sym.as_str())));
584         files.extend(extra_tracked_files);
585
586         // We also need to track used PGO profile files
587         if let Some(ref profile_instr) = sess.opts.cg.profile_use {
588             files.push(normalize_path(profile_instr.as_path().to_path_buf()));
589         }
590         if let Some(ref profile_sample) = sess.opts.unstable_opts.profile_sample_use {
591             files.push(normalize_path(profile_sample.as_path().to_path_buf()));
592         }
593
594         if sess.binary_dep_depinfo() {
595             if let Some(ref backend) = sess.opts.unstable_opts.codegen_backend {
596                 if backend.contains('.') {
597                     // If the backend name contain a `.`, it is the path to an external dynamic
598                     // library. If not, it is not a path.
599                     files.push(backend.to_string());
600                 }
601             }
602
603             boxed_resolver.borrow_mut().access(|resolver| {
604                 for cnum in resolver.cstore().crates_untracked() {
605                     let source = resolver.cstore().crate_source_untracked(cnum);
606                     if let Some((path, _)) = &source.dylib {
607                         files.push(escape_dep_filename(&path.display().to_string()));
608                     }
609                     if let Some((path, _)) = &source.rlib {
610                         files.push(escape_dep_filename(&path.display().to_string()));
611                     }
612                     if let Some((path, _)) = &source.rmeta {
613                         files.push(escape_dep_filename(&path.display().to_string()));
614                     }
615                 }
616             });
617         }
618
619         let mut file = BufWriter::new(fs::File::create(&deps_filename)?);
620         for path in out_filenames {
621             writeln!(file, "{}: {}\n", path.display(), files.join(" "))?;
622         }
623
624         // Emit a fake target for each input file to the compilation. This
625         // prevents `make` from spitting out an error if a file is later
626         // deleted. For more info see #28735
627         for path in files {
628             writeln!(file, "{path}:")?;
629         }
630
631         // Emit special comments with information about accessed environment variables.
632         let env_depinfo = sess.parse_sess.env_depinfo.borrow();
633         if !env_depinfo.is_empty() {
634             let mut envs: Vec<_> = env_depinfo
635                 .iter()
636                 .map(|(k, v)| (escape_dep_env(*k), v.map(escape_dep_env)))
637                 .collect();
638             envs.sort_unstable();
639             writeln!(file)?;
640             for (k, v) in envs {
641                 write!(file, "# env-dep:{k}")?;
642                 if let Some(v) = v {
643                     write!(file, "={v}")?;
644                 }
645                 writeln!(file)?;
646             }
647         }
648     };
649
650     match result {
651         Ok(_) => {
652             if sess.opts.json_artifact_notifications {
653                 sess.parse_sess
654                     .span_diagnostic
655                     .emit_artifact_notification(&deps_filename, "dep-info");
656             }
657         }
658         Err(error) => {
659             sess.emit_fatal(ErrorWritingDependencies { path: &deps_filename, error });
660         }
661     }
662 }
663
664 pub fn prepare_outputs(
665     sess: &Session,
666     krate: &ast::Crate,
667     boxed_resolver: &RefCell<BoxedResolver>,
668     crate_name: Symbol,
669 ) -> Result<OutputFilenames> {
670     let _timer = sess.timer("prepare_outputs");
671
672     // FIXME: rustdoc passes &[] instead of &krate.attrs here
673     let outputs = util::build_output_filenames(&krate.attrs, sess);
674
675     let output_paths =
676         generated_output_paths(sess, &outputs, sess.io.output_file.is_some(), crate_name);
677
678     // Ensure the source file isn't accidentally overwritten during compilation.
679     if let Some(ref input_path) = sess.io.input.opt_path() {
680         if sess.opts.will_create_output_file() {
681             if output_contains_path(&output_paths, input_path) {
682                 let reported = sess.emit_err(InputFileWouldBeOverWritten { path: input_path });
683                 return Err(reported);
684             }
685             if let Some(ref dir_path) = output_conflicts_with_dir(&output_paths) {
686                 let reported =
687                     sess.emit_err(GeneratedFileConflictsWithDirectory { input_path, dir_path });
688                 return Err(reported);
689             }
690         }
691     }
692
693     if let Some(ref dir) = sess.io.temps_dir {
694         if fs::create_dir_all(dir).is_err() {
695             let reported = sess.emit_err(TempsDirError);
696             return Err(reported);
697         }
698     }
699
700     write_out_deps(sess, boxed_resolver, &outputs, &output_paths);
701
702     let only_dep_info = sess.opts.output_types.contains_key(&OutputType::DepInfo)
703         && sess.opts.output_types.len() == 1;
704
705     if !only_dep_info {
706         if let Some(ref dir) = sess.io.output_dir {
707             if fs::create_dir_all(dir).is_err() {
708                 let reported = sess.emit_err(OutDirError);
709                 return Err(reported);
710             }
711         }
712     }
713
714     Ok(outputs)
715 }
716
717 pub static DEFAULT_QUERY_PROVIDERS: LazyLock<Providers> = LazyLock::new(|| {
718     let providers = &mut Providers::default();
719     providers.analysis = analysis;
720     providers.hir_crate = rustc_ast_lowering::lower_to_hir;
721     proc_macro_decls::provide(providers);
722     rustc_const_eval::provide(providers);
723     rustc_middle::hir::provide(providers);
724     mir_borrowck::provide(providers);
725     mir_build::provide(providers);
726     rustc_mir_transform::provide(providers);
727     rustc_monomorphize::provide(providers);
728     rustc_privacy::provide(providers);
729     rustc_hir_analysis::provide(providers);
730     rustc_hir_typeck::provide(providers);
731     ty::provide(providers);
732     traits::provide(providers);
733     rustc_passes::provide(providers);
734     rustc_traits::provide(providers);
735     rustc_ty_utils::provide(providers);
736     rustc_metadata::provide(providers);
737     rustc_lint::provide(providers);
738     rustc_symbol_mangling::provide(providers);
739     rustc_codegen_ssa::provide(providers);
740     *providers
741 });
742
743 pub static DEFAULT_EXTERN_QUERY_PROVIDERS: LazyLock<ExternProviders> = LazyLock::new(|| {
744     let mut extern_providers = ExternProviders::default();
745     rustc_metadata::provide_extern(&mut extern_providers);
746     rustc_codegen_ssa::provide_extern(&mut extern_providers);
747     extern_providers
748 });
749
750 pub struct QueryContext<'tcx> {
751     gcx: &'tcx GlobalCtxt<'tcx>,
752 }
753
754 impl<'tcx> QueryContext<'tcx> {
755     pub fn enter<F, R>(&mut self, f: F) -> R
756     where
757         F: FnOnce(TyCtxt<'tcx>) -> R,
758     {
759         let icx = ty::tls::ImplicitCtxt::new(self.gcx);
760         ty::tls::enter_context(&icx, |_| f(icx.tcx))
761     }
762 }
763
764 pub fn create_global_ctxt<'tcx>(
765     compiler: &'tcx Compiler,
766     lint_store: Lrc<LintStore>,
767     dep_graph: DepGraph,
768     untracked: Untracked,
769     queries: &'tcx OnceCell<TcxQueries<'tcx>>,
770     global_ctxt: &'tcx OnceCell<GlobalCtxt<'tcx>>,
771     arena: &'tcx WorkerLocal<Arena<'tcx>>,
772     hir_arena: &'tcx WorkerLocal<rustc_hir::Arena<'tcx>>,
773 ) -> QueryContext<'tcx> {
774     // We're constructing the HIR here; we don't care what we will
775     // read, since we haven't even constructed the *input* to
776     // incr. comp. yet.
777     dep_graph.assert_ignored();
778
779     let sess = &compiler.session();
780     let query_result_on_disk_cache = rustc_incremental::load_query_result_cache(sess);
781
782     let codegen_backend = compiler.codegen_backend();
783     let mut local_providers = *DEFAULT_QUERY_PROVIDERS;
784     codegen_backend.provide(&mut local_providers);
785
786     let mut extern_providers = *DEFAULT_EXTERN_QUERY_PROVIDERS;
787     codegen_backend.provide_extern(&mut extern_providers);
788
789     if let Some(callback) = compiler.override_queries {
790         callback(sess, &mut local_providers, &mut extern_providers);
791     }
792
793     let queries = queries.get_or_init(|| {
794         TcxQueries::new(local_providers, extern_providers, query_result_on_disk_cache)
795     });
796
797     let gcx = sess.time("setup_global_ctxt", || {
798         global_ctxt.get_or_init(move || {
799             TyCtxt::create_global_ctxt(
800                 sess,
801                 lint_store,
802                 arena,
803                 hir_arena,
804                 untracked,
805                 dep_graph,
806                 queries.on_disk_cache.as_ref().map(OnDiskCache::as_dyn),
807                 queries.as_dyn(),
808                 rustc_query_impl::query_callbacks(arena),
809             )
810         })
811     });
812
813     QueryContext { gcx }
814 }
815
816 /// Runs the resolution, type-checking, region checking and other
817 /// miscellaneous analysis passes on the crate.
818 fn analysis(tcx: TyCtxt<'_>, (): ()) -> Result<()> {
819     rustc_passes::hir_id_validator::check_crate(tcx);
820
821     let sess = tcx.sess;
822     let mut entry_point = None;
823
824     sess.time("misc_checking_1", || {
825         parallel!(
826             {
827                 entry_point = sess.time("looking_for_entry_point", || tcx.entry_fn(()));
828
829                 sess.time("looking_for_derive_registrar", || {
830                     tcx.ensure().proc_macro_decls_static(())
831                 });
832
833                 CStore::from_tcx(tcx).report_unused_deps(tcx);
834             },
835             {
836                 tcx.hir().par_for_each_module(|module| {
837                     tcx.ensure().check_mod_loops(module);
838                     tcx.ensure().check_mod_attrs(module);
839                     tcx.ensure().check_mod_naked_functions(module);
840                     tcx.ensure().check_mod_unstable_api_usage(module);
841                     tcx.ensure().check_mod_const_bodies(module);
842                 });
843             },
844             {
845                 sess.time("unused_lib_feature_checking", || {
846                     rustc_passes::stability::check_unused_or_stable_features(tcx)
847                 });
848             },
849             {
850                 // We force these queries to run,
851                 // since they might not otherwise get called.
852                 // This marks the corresponding crate-level attributes
853                 // as used, and ensures that their values are valid.
854                 tcx.ensure().limits(());
855                 tcx.ensure().stability_index(());
856             }
857         );
858     });
859
860     // passes are timed inside typeck
861     rustc_hir_analysis::check_crate(tcx)?;
862
863     sess.time("misc_checking_2", || {
864         parallel!(
865             {
866                 sess.time("match_checking", || {
867                     tcx.hir().par_body_owners(|def_id| tcx.ensure().check_match(def_id.to_def_id()))
868                 });
869             },
870             {
871                 sess.time("liveness_checking", || {
872                     tcx.hir().par_body_owners(|def_id| {
873                         // this must run before MIR dump, because
874                         // "not all control paths return a value" is reported here.
875                         //
876                         // maybe move the check to a MIR pass?
877                         tcx.ensure().check_liveness(def_id.to_def_id());
878                     });
879                 });
880             }
881         );
882     });
883
884     sess.time("MIR_borrow_checking", || {
885         tcx.hir().par_body_owners(|def_id| tcx.ensure().mir_borrowck(def_id));
886     });
887
888     sess.time("MIR_effect_checking", || {
889         for def_id in tcx.hir().body_owners() {
890             tcx.ensure().thir_check_unsafety(def_id);
891             if !tcx.sess.opts.unstable_opts.thir_unsafeck {
892                 rustc_mir_transform::check_unsafety::check_unsafety(tcx, def_id);
893             }
894             tcx.ensure().has_ffi_unwind_calls(def_id);
895
896             if tcx.hir().body_const_context(def_id).is_some() {
897                 tcx.ensure()
898                     .mir_drops_elaborated_and_const_checked(ty::WithOptConstParam::unknown(def_id));
899             }
900         }
901     });
902
903     sess.time("layout_testing", || layout_test::test_layout(tcx));
904
905     // Avoid overwhelming user with errors if borrow checking failed.
906     // I'm not sure how helpful this is, to be honest, but it avoids a
907     // lot of annoying errors in the ui tests (basically,
908     // lint warnings and so on -- kindck used to do this abort, but
909     // kindck is gone now). -nmatsakis
910     if let Some(reported) = sess.has_errors() {
911         return Err(reported);
912     }
913
914     sess.time("misc_checking_3", || {
915         parallel!(
916             {
917                 tcx.ensure().effective_visibilities(());
918
919                 parallel!(
920                     {
921                         tcx.ensure().check_private_in_public(());
922                     },
923                     {
924                         tcx.hir()
925                             .par_for_each_module(|module| tcx.ensure().check_mod_deathness(module));
926                     },
927                     {
928                         sess.time("lint_checking", || {
929                             rustc_lint::check_crate(tcx, || {
930                                 rustc_lint::BuiltinCombinedLateLintPass::new()
931                             });
932                         });
933                     }
934                 );
935             },
936             {
937                 sess.time("privacy_checking_modules", || {
938                     tcx.hir().par_for_each_module(|module| {
939                         tcx.ensure().check_mod_privacy(module);
940                     });
941                 });
942             }
943         );
944
945         // This check has to be run after all lints are done processing. We don't
946         // define a lint filter, as all lint checks should have finished at this point.
947         sess.time("check_lint_expectations", || tcx.check_expectations(None));
948     });
949
950     Ok(())
951 }
952
953 /// Runs the codegen backend, after which the AST and analysis can
954 /// be discarded.
955 pub fn start_codegen<'tcx>(
956     codegen_backend: &dyn CodegenBackend,
957     tcx: TyCtxt<'tcx>,
958 ) -> Box<dyn Any> {
959     info!("Pre-codegen\n{:?}", tcx.debug_stats());
960
961     let (metadata, need_metadata_module) = rustc_metadata::fs::encode_and_write_metadata(tcx);
962
963     let codegen = tcx.sess.time("codegen_crate", move || {
964         codegen_backend.codegen_crate(tcx, metadata, need_metadata_module)
965     });
966
967     // Don't run these test assertions when not doing codegen. Compiletest tries to build
968     // build-fail tests in check mode first and expects it to not give an error in that case.
969     if tcx.sess.opts.output_types.should_codegen() {
970         rustc_incremental::assert_module_sources::assert_module_sources(tcx);
971         rustc_symbol_mangling::test::report_symbol_names(tcx);
972     }
973
974     info!("Post-codegen\n{:?}", tcx.debug_stats());
975
976     if tcx.sess.opts.output_types.contains_key(&OutputType::Mir) {
977         if let Err(error) = rustc_mir_transform::dump_mir::emit_mir(tcx) {
978             tcx.sess.emit_err(CantEmitMIR { error });
979             tcx.sess.abort_if_errors();
980         }
981     }
982
983     codegen
984 }
985
986 fn get_recursion_limit(krate_attrs: &[ast::Attribute], sess: &Session) -> Limit {
987     if let Some(attr) = krate_attrs
988         .iter()
989         .find(|attr| attr.has_name(sym::recursion_limit) && attr.value_str().is_none())
990     {
991         // This is here mainly to check for using a macro, such as
992         // #![recursion_limit = foo!()]. That is not supported since that
993         // would require expanding this while in the middle of expansion,
994         // which needs to know the limit before expanding. Otherwise,
995         // validation would normally be caught in AstValidator (via
996         // `check_builtin_attribute`), but by the time that runs the macro
997         // is expanded, and it doesn't give an error.
998         validate_attr::emit_fatal_malformed_builtin_attribute(
999             &sess.parse_sess,
1000             attr,
1001             sym::recursion_limit,
1002         );
1003     }
1004     rustc_middle::middle::limits::get_recursion_limit(krate_attrs, sess)
1005 }