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Rollup merge of #99483 - compiler-errors:issue-99482, r=jyn514
[rust.git] / compiler / rustc_interface / src / passes.rs
1 use crate::interface::{Compiler, Result};
2 use crate::proc_macro_decls;
3 use crate::util;
4
5 use ast::CRATE_NODE_ID;
6 use rustc_ast::{self as ast, visit};
7 use rustc_borrowck as mir_borrowck;
8 use rustc_codegen_ssa::traits::CodegenBackend;
9 use rustc_data_structures::parallel;
10 use rustc_data_structures::sync::{Lrc, OnceCell, WorkerLocal};
11 use rustc_errors::{Applicability, ErrorGuaranteed, MultiSpan, PResult};
12 use rustc_expand::base::{ExtCtxt, LintStoreExpand, ResolverExpand};
13 use rustc_hir::def_id::StableCrateId;
14 use rustc_hir::definitions::Definitions;
15 use rustc_lint::{BufferedEarlyLint, EarlyCheckNode, LintStore};
16 use rustc_metadata::creader::CStore;
17 use rustc_middle::arena::Arena;
18 use rustc_middle::dep_graph::DepGraph;
19 use rustc_middle::ty::query::{ExternProviders, Providers};
20 use rustc_middle::ty::{self, GlobalCtxt, RegisteredTools, TyCtxt};
21 use rustc_mir_build as mir_build;
22 use rustc_parse::{parse_crate_from_file, parse_crate_from_source_str, validate_attr};
23 use rustc_passes::{self, hir_stats, layout_test};
24 use rustc_plugin_impl as plugin;
25 use rustc_query_impl::{OnDiskCache, Queries as TcxQueries};
26 use rustc_resolve::{Resolver, ResolverArenas};
27 use rustc_session::config::{CrateType, Input, OutputFilenames, OutputType};
28 use rustc_session::cstore::{CrateStoreDyn, MetadataLoader, MetadataLoaderDyn};
29 use rustc_session::output::filename_for_input;
30 use rustc_session::search_paths::PathKind;
31 use rustc_session::{Limit, Session};
32 use rustc_span::symbol::{sym, Symbol};
33 use rustc_span::FileName;
34 use rustc_trait_selection::traits;
35 use rustc_typeck as typeck;
36 use tracing::{info, warn};
37
38 use std::any::Any;
39 use std::cell::RefCell;
40 use std::ffi::OsString;
41 use std::io::{self, BufWriter, Write};
42 use std::marker::PhantomPinned;
43 use std::path::{Path, PathBuf};
44 use std::pin::Pin;
45 use std::rc::Rc;
46 use std::sync::LazyLock;
47 use std::{env, fs, iter};
48
49 pub fn parse<'a>(sess: &'a Session, input: &Input) -> PResult<'a, ast::Crate> {
50     let krate = sess.time("parse_crate", || match input {
51         Input::File(file) => parse_crate_from_file(file, &sess.parse_sess),
52         Input::Str { input, name } => {
53             parse_crate_from_source_str(name.clone(), input.clone(), &sess.parse_sess)
54         }
55     })?;
56
57     if sess.opts.unstable_opts.input_stats {
58         eprintln!("Lines of code:             {}", sess.source_map().count_lines());
59         eprintln!("Pre-expansion node count:  {}", count_nodes(&krate));
60     }
61
62     if let Some(ref s) = sess.opts.unstable_opts.show_span {
63         rustc_ast_passes::show_span::run(sess.diagnostic(), s, &krate);
64     }
65
66     if sess.opts.unstable_opts.hir_stats {
67         hir_stats::print_ast_stats(&krate, "PRE EXPANSION AST STATS");
68     }
69
70     Ok(krate)
71 }
72
73 fn count_nodes(krate: &ast::Crate) -> usize {
74     let mut counter = rustc_ast_passes::node_count::NodeCounter::new();
75     visit::walk_crate(&mut counter, krate);
76     counter.count
77 }
78
79 pub use boxed_resolver::BoxedResolver;
80 mod boxed_resolver {
81     use super::*;
82
83     pub struct BoxedResolver(Pin<Box<BoxedResolverInner>>);
84
85     struct BoxedResolverInner {
86         session: Lrc<Session>,
87         resolver_arenas: Option<ResolverArenas<'static>>,
88         resolver: Option<Resolver<'static>>,
89         _pin: PhantomPinned,
90     }
91
92     // Note: Drop order is important to prevent dangling references. Resolver must be dropped first,
93     // then resolver_arenas and session.
94     impl Drop for BoxedResolverInner {
95         fn drop(&mut self) {
96             self.resolver.take();
97             self.resolver_arenas.take();
98         }
99     }
100
101     impl BoxedResolver {
102         pub(super) fn new(
103             session: Lrc<Session>,
104             make_resolver: impl for<'a> FnOnce(&'a Session, &'a ResolverArenas<'a>) -> Resolver<'a>,
105         ) -> BoxedResolver {
106             let mut boxed_resolver = Box::new(BoxedResolverInner {
107                 session,
108                 resolver_arenas: Some(Resolver::arenas()),
109                 resolver: None,
110                 _pin: PhantomPinned,
111             });
112             // SAFETY: `make_resolver` takes a resolver arena with an arbitrary lifetime and
113             // returns a resolver with the same lifetime as the arena. We ensure that the arena
114             // outlives the resolver in the drop impl and elsewhere so these transmutes are sound.
115             unsafe {
116                 let resolver = make_resolver(
117                     std::mem::transmute::<&Session, &Session>(&boxed_resolver.session),
118                     std::mem::transmute::<&ResolverArenas<'_>, &ResolverArenas<'_>>(
119                         boxed_resolver.resolver_arenas.as_ref().unwrap(),
120                     ),
121                 );
122                 boxed_resolver.resolver = Some(resolver);
123                 BoxedResolver(Pin::new_unchecked(boxed_resolver))
124             }
125         }
126
127         pub fn access<F: for<'a> FnOnce(&mut Resolver<'a>) -> R, R>(&mut self, f: F) -> R {
128             // SAFETY: The resolver doesn't need to be pinned.
129             let mut resolver = unsafe {
130                 self.0.as_mut().map_unchecked_mut(|boxed_resolver| &mut boxed_resolver.resolver)
131             };
132             f((&mut *resolver).as_mut().unwrap())
133         }
134
135         pub fn to_resolver_outputs(
136             resolver: Rc<RefCell<BoxedResolver>>,
137         ) -> (Definitions, Box<CrateStoreDyn>, ty::ResolverOutputs, ty::ResolverAstLowering)
138         {
139             match Rc::try_unwrap(resolver) {
140                 Ok(resolver) => {
141                     let mut resolver = resolver.into_inner();
142                     // SAFETY: The resolver doesn't need to be pinned.
143                     let mut resolver = unsafe {
144                         resolver
145                             .0
146                             .as_mut()
147                             .map_unchecked_mut(|boxed_resolver| &mut boxed_resolver.resolver)
148                     };
149                     resolver.take().unwrap().into_outputs()
150                 }
151                 Err(resolver) => resolver.borrow_mut().access(|resolver| resolver.clone_outputs()),
152             }
153         }
154     }
155 }
156
157 pub fn create_resolver(
158     sess: Lrc<Session>,
159     metadata_loader: Box<MetadataLoaderDyn>,
160     krate: &ast::Crate,
161     crate_name: &str,
162 ) -> BoxedResolver {
163     tracing::trace!("create_resolver");
164     BoxedResolver::new(sess, move |sess, resolver_arenas| {
165         Resolver::new(sess, krate, crate_name, metadata_loader, resolver_arenas)
166     })
167 }
168
169 pub fn register_plugins<'a>(
170     sess: &'a Session,
171     metadata_loader: &'a dyn MetadataLoader,
172     register_lints: impl Fn(&Session, &mut LintStore),
173     mut krate: ast::Crate,
174     crate_name: &str,
175 ) -> Result<(ast::Crate, LintStore)> {
176     krate = sess.time("attributes_injection", || {
177         rustc_builtin_macros::cmdline_attrs::inject(
178             krate,
179             &sess.parse_sess,
180             &sess.opts.unstable_opts.crate_attr,
181         )
182     });
183
184     let (krate, features) = rustc_expand::config::features(sess, krate, CRATE_NODE_ID);
185     // these need to be set "early" so that expansion sees `quote` if enabled.
186     sess.init_features(features);
187
188     let crate_types = util::collect_crate_types(sess, &krate.attrs);
189     sess.init_crate_types(crate_types);
190
191     let stable_crate_id = StableCrateId::new(
192         crate_name,
193         sess.crate_types().contains(&CrateType::Executable),
194         sess.opts.cg.metadata.clone(),
195     );
196     sess.stable_crate_id.set(stable_crate_id).expect("not yet initialized");
197     rustc_incremental::prepare_session_directory(sess, crate_name, stable_crate_id)?;
198
199     if sess.opts.incremental.is_some() {
200         sess.time("incr_comp_garbage_collect_session_directories", || {
201             if let Err(e) = rustc_incremental::garbage_collect_session_directories(sess) {
202                 warn!(
203                     "Error while trying to garbage collect incremental \
204                      compilation cache directory: {}",
205                     e
206                 );
207             }
208         });
209     }
210
211     let mut lint_store = rustc_lint::new_lint_store(
212         sess.opts.unstable_opts.no_interleave_lints,
213         sess.unstable_options(),
214     );
215     register_lints(sess, &mut lint_store);
216
217     let registrars =
218         sess.time("plugin_loading", || plugin::load::load_plugins(sess, metadata_loader, &krate));
219     sess.time("plugin_registration", || {
220         let mut registry = plugin::Registry { lint_store: &mut lint_store };
221         for registrar in registrars {
222             registrar(&mut registry);
223         }
224     });
225
226     Ok((krate, lint_store))
227 }
228
229 fn pre_expansion_lint<'a>(
230     sess: &Session,
231     lint_store: &LintStore,
232     registered_tools: &RegisteredTools,
233     check_node: impl EarlyCheckNode<'a>,
234     node_name: &str,
235 ) {
236     sess.prof.generic_activity_with_arg("pre_AST_expansion_lint_checks", node_name).run(|| {
237         rustc_lint::check_ast_node(
238             sess,
239             true,
240             lint_store,
241             registered_tools,
242             None,
243             rustc_lint::BuiltinCombinedPreExpansionLintPass::new(),
244             check_node,
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: &str,
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: &str,
275     resolver: &mut Resolver<'_>,
276 ) -> Result<ast::Crate> {
277     tracing::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.err("cannot mix `bin` crate type with others");
378         }
379         if is_proc_macro_crate {
380             sess.err("cannot mix `proc-macro` crate type with others");
381         }
382     }
383
384     // For backwards compatibility, we don't try to run proc macro injection
385     // if rustdoc is run on a proc macro crate without '--crate-type proc-macro' being
386     // specified. This should only affect users who manually invoke 'rustdoc', as
387     // 'cargo doc' will automatically pass the proper '--crate-type' flags.
388     // However, we do emit a warning, to let such users know that they should
389     // start passing '--crate-type proc-macro'
390     if has_proc_macro_decls && sess.opts.actually_rustdoc && !is_proc_macro_crate {
391         let mut msg = sess.diagnostic().struct_warn(
392             "Trying to document proc macro crate \
393              without passing '--crate-type proc-macro to rustdoc",
394         );
395
396         msg.warn("The generated documentation may be incorrect");
397         msg.emit();
398     } else {
399         krate = sess.time("maybe_create_a_macro_crate", || {
400             let is_test_crate = sess.opts.test;
401             rustc_builtin_macros::proc_macro_harness::inject(
402                 sess,
403                 resolver,
404                 krate,
405                 is_proc_macro_crate,
406                 has_proc_macro_decls,
407                 is_test_crate,
408                 sess.diagnostic(),
409             )
410         });
411     }
412
413     // Done with macro expansion!
414
415     if sess.opts.unstable_opts.input_stats {
416         eprintln!("Post-expansion node count: {}", count_nodes(&krate));
417     }
418
419     if sess.opts.unstable_opts.hir_stats {
420         hir_stats::print_ast_stats(&krate, "POST EXPANSION AST STATS");
421     }
422
423     resolver.resolve_crate(&krate);
424
425     // Needs to go *after* expansion to be able to check the results of macro expansion.
426     sess.time("complete_gated_feature_checking", || {
427         rustc_ast_passes::feature_gate::check_crate(&krate, sess);
428     });
429
430     // Add all buffered lints from the `ParseSess` to the `Session`.
431     sess.parse_sess.buffered_lints.with_lock(|buffered_lints| {
432         info!("{} parse sess buffered_lints", buffered_lints.len());
433         for early_lint in buffered_lints.drain(..) {
434             resolver.lint_buffer().add_early_lint(early_lint);
435         }
436     });
437
438     // Gate identifiers containing invalid Unicode codepoints that were recovered during lexing.
439     sess.parse_sess.bad_unicode_identifiers.with_lock(|identifiers| {
440         let mut identifiers: Vec<_> = identifiers.drain().collect();
441         identifiers.sort_by_key(|&(key, _)| key);
442         for (ident, mut spans) in identifiers.into_iter() {
443             spans.sort();
444             if ident == sym::ferris {
445                 let first_span = spans[0];
446                 sess.diagnostic()
447                     .struct_span_err(
448                         MultiSpan::from(spans),
449                         "Ferris cannot be used as an identifier",
450                     )
451                     .span_suggestion(
452                         first_span,
453                         "try using their name instead",
454                         "ferris",
455                         Applicability::MaybeIncorrect,
456                     )
457                     .emit();
458             } else {
459                 sess.diagnostic().span_err(
460                     MultiSpan::from(spans),
461                     &format!("identifiers cannot contain emoji: `{}`", ident),
462                 );
463             }
464         }
465     });
466
467     sess.time("early_lint_checks", || {
468         let lint_buffer = Some(std::mem::take(resolver.lint_buffer()));
469         rustc_lint::check_ast_node(
470             sess,
471             false,
472             lint_store,
473             resolver.registered_tools(),
474             lint_buffer,
475             rustc_lint::BuiltinCombinedEarlyLintPass::new(),
476             &krate,
477         )
478     });
479
480     Ok(krate)
481 }
482
483 // Returns all the paths that correspond to generated files.
484 fn generated_output_paths(
485     sess: &Session,
486     outputs: &OutputFilenames,
487     exact_name: bool,
488     crate_name: &str,
489 ) -> Vec<PathBuf> {
490     let mut out_filenames = Vec::new();
491     for output_type in sess.opts.output_types.keys() {
492         let file = outputs.path(*output_type);
493         match *output_type {
494             // If the filename has been overridden using `-o`, it will not be modified
495             // by appending `.rlib`, `.exe`, etc., so we can skip this transformation.
496             OutputType::Exe if !exact_name => {
497                 for crate_type in sess.crate_types().iter() {
498                     let p = filename_for_input(sess, *crate_type, crate_name, outputs);
499                     out_filenames.push(p);
500                 }
501             }
502             OutputType::DepInfo if sess.opts.unstable_opts.dep_info_omit_d_target => {
503                 // Don't add the dep-info output when omitting it from dep-info targets
504             }
505             _ => {
506                 out_filenames.push(file);
507             }
508         }
509     }
510     out_filenames
511 }
512
513 // Runs `f` on every output file path and returns the first non-None result, or None if `f`
514 // returns None for every file path.
515 fn check_output<F, T>(output_paths: &[PathBuf], f: F) -> Option<T>
516 where
517     F: Fn(&PathBuf) -> Option<T>,
518 {
519     for output_path in output_paths {
520         if let Some(result) = f(output_path) {
521             return Some(result);
522         }
523     }
524     None
525 }
526
527 fn output_contains_path(output_paths: &[PathBuf], input_path: &Path) -> bool {
528     let input_path = input_path.canonicalize().ok();
529     if input_path.is_none() {
530         return false;
531     }
532     let check = |output_path: &PathBuf| {
533         if output_path.canonicalize().ok() == input_path { Some(()) } else { None }
534     };
535     check_output(output_paths, check).is_some()
536 }
537
538 fn output_conflicts_with_dir(output_paths: &[PathBuf]) -> Option<PathBuf> {
539     let check = |output_path: &PathBuf| output_path.is_dir().then(|| output_path.clone());
540     check_output(output_paths, check)
541 }
542
543 fn escape_dep_filename(filename: &str) -> String {
544     // Apparently clang and gcc *only* escape spaces:
545     // https://llvm.org/klaus/clang/commit/9d50634cfc268ecc9a7250226dd5ca0e945240d4
546     filename.replace(' ', "\\ ")
547 }
548
549 // Makefile comments only need escaping newlines and `\`.
550 // The result can be unescaped by anything that can unescape `escape_default` and friends.
551 fn escape_dep_env(symbol: Symbol) -> String {
552     let s = symbol.as_str();
553     let mut escaped = String::with_capacity(s.len());
554     for c in s.chars() {
555         match c {
556             '\n' => escaped.push_str(r"\n"),
557             '\r' => escaped.push_str(r"\r"),
558             '\\' => escaped.push_str(r"\\"),
559             _ => escaped.push(c),
560         }
561     }
562     escaped
563 }
564
565 fn write_out_deps(
566     sess: &Session,
567     boxed_resolver: &RefCell<BoxedResolver>,
568     outputs: &OutputFilenames,
569     out_filenames: &[PathBuf],
570 ) {
571     // Write out dependency rules to the dep-info file if requested
572     if !sess.opts.output_types.contains_key(&OutputType::DepInfo) {
573         return;
574     }
575     let deps_filename = outputs.path(OutputType::DepInfo);
576
577     let result = (|| -> io::Result<()> {
578         // Build a list of files used to compile the output and
579         // write Makefile-compatible dependency rules
580         let mut files: Vec<String> = sess
581             .source_map()
582             .files()
583             .iter()
584             .filter(|fmap| fmap.is_real_file())
585             .filter(|fmap| !fmap.is_imported())
586             .map(|fmap| escape_dep_filename(&fmap.name.prefer_local().to_string()))
587             .collect();
588
589         // Account for explicitly marked-to-track files
590         // (e.g. accessed in proc macros).
591         let file_depinfo = sess.parse_sess.file_depinfo.borrow();
592         let extra_tracked_files = file_depinfo.iter().map(|path_sym| {
593             let path = PathBuf::from(path_sym.as_str());
594             let file = FileName::from(path);
595             escape_dep_filename(&file.prefer_local().to_string())
596         });
597         files.extend(extra_tracked_files);
598
599         if sess.binary_dep_depinfo() {
600             if let Some(ref backend) = sess.opts.unstable_opts.codegen_backend {
601                 if backend.contains('.') {
602                     // If the backend name contain a `.`, it is the path to an external dynamic
603                     // library. If not, it is not a path.
604                     files.push(backend.to_string());
605                 }
606             }
607
608             boxed_resolver.borrow_mut().access(|resolver| {
609                 for cnum in resolver.cstore().crates_untracked() {
610                     let source = resolver.cstore().crate_source_untracked(cnum);
611                     if let Some((path, _)) = &source.dylib {
612                         files.push(escape_dep_filename(&path.display().to_string()));
613                     }
614                     if let Some((path, _)) = &source.rlib {
615                         files.push(escape_dep_filename(&path.display().to_string()));
616                     }
617                     if let Some((path, _)) = &source.rmeta {
618                         files.push(escape_dep_filename(&path.display().to_string()));
619                     }
620                 }
621             });
622         }
623
624         let mut file = BufWriter::new(fs::File::create(&deps_filename)?);
625         for path in out_filenames {
626             writeln!(file, "{}: {}\n", path.display(), files.join(" "))?;
627         }
628
629         // Emit a fake target for each input file to the compilation. This
630         // prevents `make` from spitting out an error if a file is later
631         // deleted. For more info see #28735
632         for path in files {
633             writeln!(file, "{}:", path)?;
634         }
635
636         // Emit special comments with information about accessed environment variables.
637         let env_depinfo = sess.parse_sess.env_depinfo.borrow();
638         if !env_depinfo.is_empty() {
639             let mut envs: Vec<_> = env_depinfo
640                 .iter()
641                 .map(|(k, v)| (escape_dep_env(*k), v.map(escape_dep_env)))
642                 .collect();
643             envs.sort_unstable();
644             writeln!(file)?;
645             for (k, v) in envs {
646                 write!(file, "# env-dep:{}", k)?;
647                 if let Some(v) = v {
648                     write!(file, "={}", v)?;
649                 }
650                 writeln!(file)?;
651             }
652         }
653
654         Ok(())
655     })();
656
657     match result {
658         Ok(_) => {
659             if sess.opts.json_artifact_notifications {
660                 sess.parse_sess
661                     .span_diagnostic
662                     .emit_artifact_notification(&deps_filename, "dep-info");
663             }
664         }
665         Err(e) => sess.fatal(&format!(
666             "error writing dependencies to `{}`: {}",
667             deps_filename.display(),
668             e
669         )),
670     }
671 }
672
673 pub fn prepare_outputs(
674     sess: &Session,
675     compiler: &Compiler,
676     krate: &ast::Crate,
677     boxed_resolver: &RefCell<BoxedResolver>,
678     crate_name: &str,
679 ) -> Result<OutputFilenames> {
680     let _timer = sess.timer("prepare_outputs");
681
682     // FIXME: rustdoc passes &[] instead of &krate.attrs here
683     let outputs = util::build_output_filenames(
684         &compiler.input,
685         &compiler.output_dir,
686         &compiler.output_file,
687         &compiler.temps_dir,
688         &krate.attrs,
689         sess,
690     );
691
692     let output_paths =
693         generated_output_paths(sess, &outputs, compiler.output_file.is_some(), crate_name);
694
695     // Ensure the source file isn't accidentally overwritten during compilation.
696     if let Some(ref input_path) = compiler.input_path {
697         if sess.opts.will_create_output_file() {
698             if output_contains_path(&output_paths, input_path) {
699                 let reported = sess.err(&format!(
700                     "the input file \"{}\" would be overwritten by the generated \
701                         executable",
702                     input_path.display()
703                 ));
704                 return Err(reported);
705             }
706             if let Some(dir_path) = output_conflicts_with_dir(&output_paths) {
707                 let reported = sess.err(&format!(
708                     "the generated executable for the input file \"{}\" conflicts with the \
709                         existing directory \"{}\"",
710                     input_path.display(),
711                     dir_path.display()
712                 ));
713                 return Err(reported);
714             }
715         }
716     }
717
718     if let Some(ref dir) = compiler.temps_dir {
719         if fs::create_dir_all(dir).is_err() {
720             let reported =
721                 sess.err("failed to find or create the directory specified by `--temps-dir`");
722             return Err(reported);
723         }
724     }
725
726     write_out_deps(sess, boxed_resolver, &outputs, &output_paths);
727
728     let only_dep_info = sess.opts.output_types.contains_key(&OutputType::DepInfo)
729         && sess.opts.output_types.len() == 1;
730
731     if !only_dep_info {
732         if let Some(ref dir) = compiler.output_dir {
733             if fs::create_dir_all(dir).is_err() {
734                 let reported =
735                     sess.err("failed to find or create the directory specified by `--out-dir`");
736                 return Err(reported);
737             }
738         }
739     }
740
741     Ok(outputs)
742 }
743
744 pub static DEFAULT_QUERY_PROVIDERS: LazyLock<Providers> = LazyLock::new(|| {
745     let providers = &mut Providers::default();
746     providers.analysis = analysis;
747     providers.hir_crate = rustc_ast_lowering::lower_to_hir;
748     proc_macro_decls::provide(providers);
749     rustc_const_eval::provide(providers);
750     rustc_middle::hir::provide(providers);
751     mir_borrowck::provide(providers);
752     mir_build::provide(providers);
753     rustc_mir_transform::provide(providers);
754     rustc_monomorphize::provide(providers);
755     rustc_privacy::provide(providers);
756     typeck::provide(providers);
757     ty::provide(providers);
758     traits::provide(providers);
759     rustc_passes::provide(providers);
760     rustc_resolve::provide(providers);
761     rustc_traits::provide(providers);
762     rustc_ty_utils::provide(providers);
763     rustc_metadata::provide(providers);
764     rustc_lint::provide(providers);
765     rustc_symbol_mangling::provide(providers);
766     rustc_codegen_ssa::provide(providers);
767     *providers
768 });
769
770 pub static DEFAULT_EXTERN_QUERY_PROVIDERS: LazyLock<ExternProviders> = LazyLock::new(|| {
771     let mut extern_providers = ExternProviders::default();
772     rustc_metadata::provide_extern(&mut extern_providers);
773     rustc_codegen_ssa::provide_extern(&mut extern_providers);
774     extern_providers
775 });
776
777 pub struct QueryContext<'tcx> {
778     gcx: &'tcx GlobalCtxt<'tcx>,
779 }
780
781 impl<'tcx> QueryContext<'tcx> {
782     pub fn enter<F, R>(&mut self, f: F) -> R
783     where
784         F: FnOnce(TyCtxt<'tcx>) -> R,
785     {
786         let icx = ty::tls::ImplicitCtxt::new(self.gcx);
787         ty::tls::enter_context(&icx, |_| f(icx.tcx))
788     }
789 }
790
791 pub fn create_global_ctxt<'tcx>(
792     compiler: &'tcx Compiler,
793     lint_store: Lrc<LintStore>,
794     krate: Lrc<ast::Crate>,
795     dep_graph: DepGraph,
796     resolver: Rc<RefCell<BoxedResolver>>,
797     outputs: OutputFilenames,
798     crate_name: &str,
799     queries: &'tcx OnceCell<TcxQueries<'tcx>>,
800     global_ctxt: &'tcx OnceCell<GlobalCtxt<'tcx>>,
801     arena: &'tcx WorkerLocal<Arena<'tcx>>,
802     hir_arena: &'tcx WorkerLocal<rustc_hir::Arena<'tcx>>,
803 ) -> QueryContext<'tcx> {
804     // We're constructing the HIR here; we don't care what we will
805     // read, since we haven't even constructed the *input* to
806     // incr. comp. yet.
807     dep_graph.assert_ignored();
808
809     let (definitions, cstore, resolver_outputs, resolver_for_lowering) =
810         BoxedResolver::to_resolver_outputs(resolver);
811
812     let sess = &compiler.session();
813     let query_result_on_disk_cache = rustc_incremental::load_query_result_cache(sess);
814
815     let codegen_backend = compiler.codegen_backend();
816     let mut local_providers = *DEFAULT_QUERY_PROVIDERS;
817     codegen_backend.provide(&mut local_providers);
818
819     let mut extern_providers = *DEFAULT_EXTERN_QUERY_PROVIDERS;
820     codegen_backend.provide_extern(&mut extern_providers);
821
822     if let Some(callback) = compiler.override_queries {
823         callback(sess, &mut local_providers, &mut extern_providers);
824     }
825
826     let queries = queries.get_or_init(|| {
827         TcxQueries::new(local_providers, extern_providers, query_result_on_disk_cache)
828     });
829
830     let gcx = sess.time("setup_global_ctxt", || {
831         global_ctxt.get_or_init(move || {
832             TyCtxt::create_global_ctxt(
833                 sess,
834                 lint_store,
835                 arena,
836                 hir_arena,
837                 definitions,
838                 cstore,
839                 resolver_outputs,
840                 resolver_for_lowering,
841                 krate,
842                 dep_graph,
843                 queries.on_disk_cache.as_ref().map(OnDiskCache::as_dyn),
844                 queries.as_dyn(),
845                 rustc_query_impl::query_callbacks(arena),
846                 crate_name,
847                 outputs,
848             )
849         })
850     });
851
852     QueryContext { gcx }
853 }
854
855 /// Runs the resolution, type-checking, region checking and other
856 /// miscellaneous analysis passes on the crate.
857 fn analysis(tcx: TyCtxt<'_>, (): ()) -> Result<()> {
858     rustc_passes::hir_id_validator::check_crate(tcx);
859
860     let sess = tcx.sess;
861     let mut entry_point = None;
862
863     sess.time("misc_checking_1", || {
864         parallel!(
865             {
866                 entry_point = sess.time("looking_for_entry_point", || tcx.entry_fn(()));
867
868                 sess.time("looking_for_derive_registrar", || {
869                     tcx.ensure().proc_macro_decls_static(())
870                 });
871
872                 CStore::from_tcx(tcx).report_unused_deps(tcx);
873             },
874             {
875                 tcx.hir().par_for_each_module(|module| {
876                     tcx.ensure().check_mod_loops(module);
877                     tcx.ensure().check_mod_attrs(module);
878                     tcx.ensure().check_mod_naked_functions(module);
879                     tcx.ensure().check_mod_unstable_api_usage(module);
880                     tcx.ensure().check_mod_const_bodies(module);
881                 });
882             },
883             {
884                 sess.time("unused_lib_feature_checking", || {
885                     rustc_passes::stability::check_unused_or_stable_features(tcx)
886                 });
887             },
888             {
889                 // We force these queries to run,
890                 // since they might not otherwise get called.
891                 // This marks the corresponding crate-level attributes
892                 // as used, and ensures that their values are valid.
893                 tcx.ensure().limits(());
894                 tcx.ensure().stability_index(());
895             }
896         );
897     });
898
899     // passes are timed inside typeck
900     typeck::check_crate(tcx)?;
901
902     sess.time("misc_checking_2", || {
903         parallel!(
904             {
905                 sess.time("match_checking", || {
906                     tcx.hir().par_body_owners(|def_id| tcx.ensure().check_match(def_id.to_def_id()))
907                 });
908             },
909             {
910                 sess.time("liveness_and_intrinsic_checking", || {
911                     tcx.hir().par_for_each_module(|module| {
912                         // this must run before MIR dump, because
913                         // "not all control paths return a value" is reported here.
914                         //
915                         // maybe move the check to a MIR pass?
916                         tcx.ensure().check_mod_liveness(module);
917                     });
918                 });
919             }
920         );
921     });
922
923     sess.time("MIR_borrow_checking", || {
924         tcx.hir().par_body_owners(|def_id| tcx.ensure().mir_borrowck(def_id));
925     });
926
927     sess.time("MIR_effect_checking", || {
928         for def_id in tcx.hir().body_owners() {
929             tcx.ensure().thir_check_unsafety(def_id);
930             if !tcx.sess.opts.unstable_opts.thir_unsafeck {
931                 rustc_mir_transform::check_unsafety::check_unsafety(tcx, def_id);
932             }
933             tcx.ensure().has_ffi_unwind_calls(def_id);
934
935             if tcx.hir().body_const_context(def_id).is_some() {
936                 tcx.ensure()
937                     .mir_drops_elaborated_and_const_checked(ty::WithOptConstParam::unknown(def_id));
938             }
939         }
940     });
941
942     sess.time("layout_testing", || layout_test::test_layout(tcx));
943
944     // Avoid overwhelming user with errors if borrow checking failed.
945     // I'm not sure how helpful this is, to be honest, but it avoids a
946     // lot of annoying errors in the ui tests (basically,
947     // lint warnings and so on -- kindck used to do this abort, but
948     // kindck is gone now). -nmatsakis
949     if let Some(reported) = sess.has_errors() {
950         return Err(reported);
951     }
952
953     sess.time("misc_checking_3", || {
954         parallel!(
955             {
956                 tcx.ensure().privacy_access_levels(());
957
958                 parallel!(
959                     {
960                         tcx.ensure().check_private_in_public(());
961                     },
962                     {
963                         tcx.hir()
964                             .par_for_each_module(|module| tcx.ensure().check_mod_deathness(module));
965                     },
966                     {
967                         sess.time("lint_checking", || {
968                             rustc_lint::check_crate(tcx, || {
969                                 rustc_lint::BuiltinCombinedLateLintPass::new()
970                             });
971                         });
972                     }
973                 );
974             },
975             {
976                 sess.time("privacy_checking_modules", || {
977                     tcx.hir().par_for_each_module(|module| {
978                         tcx.ensure().check_mod_privacy(module);
979                     });
980                 });
981             }
982         );
983
984         // This check has to be run after all lints are done processing. We don't
985         // define a lint filter, as all lint checks should have finished at this point.
986         sess.time("check_lint_expectations", || tcx.check_expectations(None));
987     });
988
989     Ok(())
990 }
991
992 /// Runs the codegen backend, after which the AST and analysis can
993 /// be discarded.
994 pub fn start_codegen<'tcx>(
995     codegen_backend: &dyn CodegenBackend,
996     tcx: TyCtxt<'tcx>,
997     outputs: &OutputFilenames,
998 ) -> Box<dyn Any> {
999     info!("Pre-codegen\n{:?}", tcx.debug_stats());
1000
1001     let (metadata, need_metadata_module) =
1002         rustc_metadata::fs::encode_and_write_metadata(tcx, outputs);
1003
1004     let codegen = tcx.sess.time("codegen_crate", move || {
1005         codegen_backend.codegen_crate(tcx, metadata, need_metadata_module)
1006     });
1007
1008     // Don't run these test assertions when not doing codegen. Compiletest tries to build
1009     // build-fail tests in check mode first and expects it to not give an error in that case.
1010     if tcx.sess.opts.output_types.should_codegen() {
1011         rustc_incremental::assert_module_sources::assert_module_sources(tcx);
1012         rustc_symbol_mangling::test::report_symbol_names(tcx);
1013     }
1014
1015     info!("Post-codegen\n{:?}", tcx.debug_stats());
1016
1017     if tcx.sess.opts.output_types.contains_key(&OutputType::Mir) {
1018         if let Err(e) = rustc_mir_transform::dump_mir::emit_mir(tcx, outputs) {
1019             tcx.sess.err(&format!("could not emit MIR: {}", e));
1020             tcx.sess.abort_if_errors();
1021         }
1022     }
1023
1024     codegen
1025 }
1026
1027 fn get_recursion_limit(krate_attrs: &[ast::Attribute], sess: &Session) -> Limit {
1028     if let Some(attr) = krate_attrs
1029         .iter()
1030         .find(|attr| attr.has_name(sym::recursion_limit) && attr.value_str().is_none())
1031     {
1032         // This is here mainly to check for using a macro, such as
1033         // #![recursion_limit = foo!()]. That is not supported since that
1034         // would require expanding this while in the middle of expansion,
1035         // which needs to know the limit before expanding. Otherwise,
1036         // validation would normally be caught in AstValidator (via
1037         // `check_builtin_attribute`), but by the time that runs the macro
1038         // is expanded, and it doesn't give an error.
1039         validate_attr::emit_fatal_malformed_builtin_attribute(
1040             &sess.parse_sess,
1041             attr,
1042             sym::recursion_limit,
1043         );
1044     }
1045     rustc_middle::middle::limits::get_recursion_limit(krate_attrs, sess)
1046 }