5 //! This API is completely unstable and subject to change.
7 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
10 #![recursion_limit = "256"]
11 #![allow(rustc::potential_query_instability)]
16 pub extern crate rustc_plugin_impl as plugin;
19 use rustc_codegen_ssa::{traits::CodegenBackend, CodegenResults};
20 use rustc_data_structures::profiling::{get_resident_set_size, print_time_passes_entry};
21 use rustc_data_structures::sync::SeqCst;
22 use rustc_errors::registry::{InvalidErrorCode, Registry};
23 use rustc_errors::{ErrorGuaranteed, PResult};
24 use rustc_feature::find_gated_cfg;
25 use rustc_interface::util::{self, collect_crate_types, get_codegen_backend};
26 use rustc_interface::{interface, Queries};
27 use rustc_lint::LintStore;
28 use rustc_log::stdout_isatty;
29 use rustc_metadata::locator;
30 use rustc_save_analysis as save;
31 use rustc_save_analysis::DumpHandler;
32 use rustc_session::config::{nightly_options, CG_OPTIONS, Z_OPTIONS};
33 use rustc_session::config::{ErrorOutputType, Input, OutputType, PrintRequest, TrimmedDefPaths};
34 use rustc_session::cstore::MetadataLoader;
35 use rustc_session::getopts;
36 use rustc_session::lint::{Lint, LintId};
37 use rustc_session::{config, DiagnosticOutput, Session};
38 use rustc_session::{early_error, early_error_no_abort, early_warn};
39 use rustc_span::source_map::{FileLoader, FileName};
40 use rustc_span::symbol::sym;
41 use rustc_target::json::ToJson;
45 use std::default::Default;
47 use std::ffi::OsString;
49 use std::io::{self, Read, Write};
50 use std::panic::{self, catch_unwind};
51 use std::path::PathBuf;
52 use std::process::{self, Command, Stdio};
54 use std::sync::LazyLock;
55 use std::time::Instant;
60 /// Exit status code used for successful compilation and help output.
61 pub const EXIT_SUCCESS: i32 = 0;
63 /// Exit status code used for compilation failures and invalid flags.
64 pub const EXIT_FAILURE: i32 = 1;
66 const BUG_REPORT_URL: &str = "https://github.com/rust-lang/rust/issues/new\
67 ?labels=C-bug%2C+I-ICE%2C+T-compiler&template=ice.md";
69 const ICE_REPORT_COMPILER_FLAGS: &[&str] = &["-Z", "-C", "--crate-type"];
71 const ICE_REPORT_COMPILER_FLAGS_EXCLUDE: &[&str] = &["metadata", "extra-filename"];
73 const ICE_REPORT_COMPILER_FLAGS_STRIP_VALUE: &[&str] = &["incremental"];
75 pub fn abort_on_err<T>(result: Result<T, ErrorGuaranteed>, sess: &Session) -> T {
78 sess.abort_if_errors();
79 panic!("error reported but abort_if_errors didn't abort???");
86 /// Called before creating the compiler instance
87 fn config(&mut self, _config: &mut interface::Config) {}
88 /// Called after parsing. Return value instructs the compiler whether to
89 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
90 fn after_parsing<'tcx>(
92 _compiler: &interface::Compiler,
93 _queries: &'tcx Queries<'tcx>,
97 /// Called after expansion. Return value instructs the compiler whether to
98 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
99 fn after_expansion<'tcx>(
101 _compiler: &interface::Compiler,
102 _queries: &'tcx Queries<'tcx>,
104 Compilation::Continue
106 /// Called after analysis. Return value instructs the compiler whether to
107 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
108 fn after_analysis<'tcx>(
110 _compiler: &interface::Compiler,
111 _queries: &'tcx Queries<'tcx>,
113 Compilation::Continue
118 pub struct TimePassesCallbacks {
122 impl Callbacks for TimePassesCallbacks {
123 fn config(&mut self, config: &mut interface::Config) {
124 // If a --prints=... option has been given, we don't print the "total"
125 // time because it will mess up the --prints output. See #64339.
126 self.time_passes = config.opts.prints.is_empty() && config.opts.time_passes();
127 config.opts.trimmed_def_paths = TrimmedDefPaths::GoodPath;
131 pub fn diagnostics_registry() -> Registry {
132 Registry::new(rustc_error_codes::DIAGNOSTICS)
135 /// This is the primary entry point for rustc.
136 pub struct RunCompiler<'a, 'b> {
137 at_args: &'a [String],
138 callbacks: &'b mut (dyn Callbacks + Send),
139 file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
140 emitter: Option<Box<dyn Write + Send>>,
141 make_codegen_backend:
142 Option<Box<dyn FnOnce(&config::Options) -> Box<dyn CodegenBackend> + Send>>,
145 impl<'a, 'b> RunCompiler<'a, 'b> {
146 pub fn new(at_args: &'a [String], callbacks: &'b mut (dyn Callbacks + Send)) -> Self {
147 Self { at_args, callbacks, file_loader: None, emitter: None, make_codegen_backend: None }
150 /// Set a custom codegen backend.
153 pub fn set_make_codegen_backend(
155 make_codegen_backend: Option<
156 Box<dyn FnOnce(&config::Options) -> Box<dyn CodegenBackend> + Send>,
159 self.make_codegen_backend = make_codegen_backend;
163 /// Emit diagnostics to the specified location.
166 pub fn set_emitter(&mut self, emitter: Option<Box<dyn Write + Send>>) -> &mut Self {
167 self.emitter = emitter;
171 /// Load files from sources other than the file system.
174 pub fn set_file_loader(
176 file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
178 self.file_loader = file_loader;
182 /// Parse args and run the compiler.
183 pub fn run(self) -> interface::Result<()> {
189 self.make_codegen_backend,
195 callbacks: &mut (dyn Callbacks + Send),
196 file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
197 emitter: Option<Box<dyn Write + Send>>,
198 make_codegen_backend: Option<
199 Box<dyn FnOnce(&config::Options) -> Box<dyn CodegenBackend> + Send>,
201 ) -> interface::Result<()> {
202 let args = args::arg_expand_all(at_args);
204 let diagnostic_output = emitter.map_or(DiagnosticOutput::Default, DiagnosticOutput::Raw);
205 let Some(matches) = handle_options(&args) else { return Ok(()) };
207 let sopts = config::build_session_options(&matches);
209 if let Some(ref code) = matches.opt_str("explain") {
210 handle_explain(diagnostics_registry(), code, sopts.error_format);
214 let cfg = interface::parse_cfgspecs(matches.opt_strs("cfg"));
215 let check_cfg = interface::parse_check_cfg(matches.opt_strs("check-cfg"));
216 let (odir, ofile) = make_output(&matches);
217 let mut config = interface::Config {
220 crate_check_cfg: check_cfg,
221 input: Input::File(PathBuf::new()),
227 lint_caps: Default::default(),
228 parse_sess_created: None,
229 register_lints: None,
230 override_queries: None,
231 make_codegen_backend,
232 registry: diagnostics_registry(),
235 match make_input(config.opts.error_format, &matches.free) {
236 Err(reported) => return Err(reported),
237 Ok(Some((input, input_file_path))) => {
238 config.input = input;
239 config.input_path = input_file_path;
241 callbacks.config(&mut config);
243 Ok(None) => match matches.free.len() {
245 callbacks.config(&mut config);
246 interface::run_compiler(config, |compiler| {
247 let sopts = &compiler.session().opts;
248 if sopts.describe_lints {
249 let mut lint_store = rustc_lint::new_lint_store(
250 sopts.unstable_opts.no_interleave_lints,
251 compiler.session().enable_internal_lints(),
253 let registered_lints =
254 if let Some(register_lints) = compiler.register_lints() {
255 register_lints(compiler.session(), &mut lint_store);
260 describe_lints(compiler.session(), &lint_store, registered_lints);
263 let should_stop = print_crate_info(
264 &***compiler.codegen_backend(),
267 compiler.output_dir(),
268 compiler.output_file(),
269 compiler.temps_dir(),
272 if should_stop == Compilation::Stop {
275 early_error(sopts.error_format, "no input filename given")
279 1 => panic!("make_input should have provided valid inputs"),
281 config.opts.error_format,
283 "multiple input filenames provided (first two filenames are `{}` and `{}`)",
284 matches.free[0], matches.free[1],
290 interface::run_compiler(config, |compiler| {
291 let sess = compiler.session();
292 let should_stop = print_crate_info(
293 &***compiler.codegen_backend(),
295 Some(compiler.input()),
296 compiler.output_dir(),
297 compiler.output_file(),
298 compiler.temps_dir(),
301 list_metadata(sess, &*compiler.codegen_backend().metadata_loader(), compiler.input())
303 .and_then(|| try_process_rlink(sess, compiler));
305 if should_stop == Compilation::Stop {
306 return sess.compile_status();
309 let linker = compiler.enter(|queries| {
310 let early_exit = || sess.compile_status().map(|_| None);
313 if let Some(ppm) = &sess.opts.pretty {
314 if ppm.needs_ast_map() {
315 let expanded_crate = queries.expansion()?.peek().0.clone();
316 queries.global_ctxt()?.peek_mut().enter(|tcx| {
317 pretty::print_after_hir_lowering(
322 compiler.output_file().as_ref().map(|p| &**p),
327 let krate = queries.parse()?.take();
328 pretty::print_after_parsing(
333 compiler.output_file().as_ref().map(|p| &**p),
336 trace!("finished pretty-printing");
340 if callbacks.after_parsing(compiler, queries) == Compilation::Stop {
344 if sess.opts.unstable_opts.parse_only || sess.opts.unstable_opts.show_span.is_some() {
349 let (_, lint_store) = &*queries.register_plugins()?.peek();
351 // Lint plugins are registered; now we can process command line flags.
352 if sess.opts.describe_lints {
353 describe_lints(sess, lint_store, true);
358 queries.expansion()?;
359 if callbacks.after_expansion(compiler, queries) == Compilation::Stop {
363 queries.prepare_outputs()?;
365 if sess.opts.output_types.contains_key(&OutputType::DepInfo)
366 && sess.opts.output_types.len() == 1
371 queries.global_ctxt()?;
373 if sess.opts.unstable_opts.no_analysis {
377 queries.global_ctxt()?.peek_mut().enter(|tcx| {
378 let result = tcx.analysis(());
379 if sess.opts.unstable_opts.save_analysis {
380 let crate_name = queries.crate_name()?.peek().clone();
381 sess.time("save_analysis", || {
388 compiler.output_dir().as_ref().map(|p| &**p),
397 if callbacks.after_analysis(compiler, queries) == Compilation::Stop {
401 queries.ongoing_codegen()?;
403 if sess.opts.unstable_opts.print_type_sizes {
404 sess.code_stats.print_type_sizes();
407 let linker = queries.linker()?;
411 if let Some(linker) = linker {
412 let _timer = sess.timer("link");
416 if sess.opts.unstable_opts.perf_stats {
417 sess.print_perf_stats();
420 if sess.opts.unstable_opts.print_fuel.is_some() {
422 "Fuel used by {}: {}",
423 sess.opts.unstable_opts.print_fuel.as_ref().unwrap(),
424 sess.print_fuel.load(SeqCst)
433 pub fn set_sigpipe_handler() {
435 // Set the SIGPIPE signal handler, so that an EPIPE
436 // will cause rustc to terminate, as expected.
437 assert_ne!(libc::signal(libc::SIGPIPE, libc::SIG_DFL), libc::SIG_ERR);
442 pub fn set_sigpipe_handler() {}
444 // Extract output directory and file from matches.
445 fn make_output(matches: &getopts::Matches) -> (Option<PathBuf>, Option<PathBuf>) {
446 let odir = matches.opt_str("out-dir").map(|o| PathBuf::from(&o));
447 let ofile = matches.opt_str("o").map(|o| PathBuf::from(&o));
451 // Extract input (string or file and optional path) from matches.
453 error_format: ErrorOutputType,
454 free_matches: &[String],
455 ) -> Result<Option<(Input, Option<PathBuf>)>, ErrorGuaranteed> {
456 if free_matches.len() == 1 {
457 let ifile = &free_matches[0];
459 let mut src = String::new();
460 if io::stdin().read_to_string(&mut src).is_err() {
461 // Immediately stop compilation if there was an issue reading
462 // the input (for example if the input stream is not UTF-8).
463 let reported = early_error_no_abort(
465 "couldn't read from stdin, as it did not contain valid UTF-8",
467 return Err(reported);
469 if let Ok(path) = env::var("UNSTABLE_RUSTDOC_TEST_PATH") {
470 let line = env::var("UNSTABLE_RUSTDOC_TEST_LINE").expect(
471 "when UNSTABLE_RUSTDOC_TEST_PATH is set \
472 UNSTABLE_RUSTDOC_TEST_LINE also needs to be set",
474 let line = isize::from_str_radix(&line, 10)
475 .expect("UNSTABLE_RUSTDOC_TEST_LINE needs to be an number");
476 let file_name = FileName::doc_test_source_code(PathBuf::from(path), line);
477 Ok(Some((Input::Str { name: file_name, input: src }, None)))
479 Ok(Some((Input::Str { name: FileName::anon_source_code(&src), input: src }, None)))
482 Ok(Some((Input::File(PathBuf::from(ifile)), Some(PathBuf::from(ifile)))))
489 /// Whether to stop or continue compilation.
490 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
491 pub enum Compilation {
497 pub fn and_then<F: FnOnce() -> Compilation>(self, next: F) -> Compilation {
499 Compilation::Stop => Compilation::Stop,
500 Compilation::Continue => next(),
505 fn handle_explain(registry: Registry, code: &str, output: ErrorOutputType) {
506 let upper_cased_code = code.to_ascii_uppercase();
507 let normalised = if upper_cased_code.starts_with('E') {
510 format!("E{0:0>4}", code)
512 match registry.try_find_description(&normalised) {
513 Ok(Some(description)) => {
514 let mut is_in_code_block = false;
515 let mut text = String::new();
516 // Slice off the leading newline and print.
517 for line in description.lines() {
519 line.find(|c: char| !c.is_whitespace()).unwrap_or_else(|| line.len());
520 let dedented_line = &line[indent_level..];
521 if dedented_line.starts_with("```") {
522 is_in_code_block = !is_in_code_block;
523 text.push_str(&line[..(indent_level + 3)]);
524 } else if is_in_code_block && dedented_line.starts_with("# ") {
532 show_content_with_pager(&text);
538 early_error(output, &format!("no extended information for {}", code));
540 Err(InvalidErrorCode) => {
541 early_error(output, &format!("{} is not a valid error code", code));
546 fn show_content_with_pager(content: &str) {
547 let pager_name = env::var_os("PAGER").unwrap_or_else(|| {
548 if cfg!(windows) { OsString::from("more.com") } else { OsString::from("less") }
551 let mut fallback_to_println = false;
553 match Command::new(pager_name).stdin(Stdio::piped()).spawn() {
555 if let Some(pipe) = pager.stdin.as_mut() {
556 if pipe.write_all(content.as_bytes()).is_err() {
557 fallback_to_println = true;
561 if pager.wait().is_err() {
562 fallback_to_println = true;
566 fallback_to_println = true;
570 // If pager fails for whatever reason, we should still print the content
571 // to standard output
572 if fallback_to_println {
573 print!("{}", content);
577 pub fn try_process_rlink(sess: &Session, compiler: &interface::Compiler) -> Compilation {
578 if sess.opts.unstable_opts.link_only {
579 if let Input::File(file) = compiler.input() {
580 // FIXME: #![crate_type] and #![crate_name] support not implemented yet
581 sess.init_crate_types(collect_crate_types(sess, &[]));
582 let outputs = compiler.build_output_filenames(sess, &[]);
583 let rlink_data = fs::read(file).unwrap_or_else(|err| {
584 sess.fatal(&format!("failed to read rlink file: {}", err));
586 let codegen_results = match CodegenResults::deserialize_rlink(rlink_data) {
587 Ok(codegen) => codegen,
589 sess.fatal(&format!("Could not deserialize .rlink file: {error}"));
592 let result = compiler.codegen_backend().link(sess, codegen_results, &outputs);
593 abort_on_err(result, sess);
595 sess.fatal("rlink must be a file")
599 Compilation::Continue
603 pub fn list_metadata(
605 metadata_loader: &dyn MetadataLoader,
608 if sess.opts.unstable_opts.ls {
610 Input::File(ref ifile) => {
611 let path = &(*ifile);
612 let mut v = Vec::new();
613 locator::list_file_metadata(&sess.target, path, metadata_loader, &mut v).unwrap();
614 println!("{}", String::from_utf8(v).unwrap());
616 Input::Str { .. } => {
617 early_error(ErrorOutputType::default(), "cannot list metadata for stdin");
620 return Compilation::Stop;
623 Compilation::Continue
627 codegen_backend: &dyn CodegenBackend,
629 input: Option<&Input>,
630 odir: &Option<PathBuf>,
631 ofile: &Option<PathBuf>,
632 temps_dir: &Option<PathBuf>,
634 use rustc_session::config::PrintRequest::*;
635 // NativeStaticLibs and LinkArgs are special - printed during linking
636 // (empty iterator returns true)
637 if sess.opts.prints.iter().all(|&p| p == NativeStaticLibs || p == LinkArgs) {
638 return Compilation::Continue;
641 let attrs = match input {
644 let result = parse_crate_attrs(sess, input);
646 Ok(attrs) => Some(attrs),
647 Err(mut parse_error) => {
649 return Compilation::Stop;
654 for req in &sess.opts.prints {
657 let mut targets = rustc_target::spec::TARGETS.iter().copied().collect::<Vec<_>>();
658 targets.sort_unstable();
659 println!("{}", targets.join("\n"));
661 Sysroot => println!("{}", sess.sysroot.display()),
662 TargetLibdir => println!("{}", sess.target_tlib_path.dir.display()),
664 println!("{}", serde_json::to_string_pretty(&sess.target.to_json()).unwrap());
666 FileNames | CrateName => {
667 let input = input.unwrap_or_else(|| {
668 early_error(ErrorOutputType::default(), "no input file provided")
670 let attrs = attrs.as_ref().unwrap();
671 let t_outputs = rustc_interface::util::build_output_filenames(
672 input, odir, ofile, temps_dir, attrs, sess,
674 let id = rustc_session::output::find_crate_name(sess, attrs, input);
675 if *req == PrintRequest::CrateName {
679 let crate_types = collect_crate_types(sess, attrs);
680 for &style in &crate_types {
682 rustc_session::output::filename_for_input(sess, style, &id, &t_outputs);
683 println!("{}", fname.file_name().unwrap().to_string_lossy());
691 .filter_map(|&(name, value)| {
692 // Note that crt-static is a specially recognized cfg
693 // directive that's printed out here as part of
694 // rust-lang/rust#37406, but in general the
695 // `target_feature` cfg is gated under
696 // rust-lang/rust#29717. For now this is just
697 // specifically allowing the crt-static cfg and that's
698 // it, this is intended to get into Cargo and then go
699 // through to build scripts.
700 if (name != sym::target_feature || value != Some(sym::crt_dash_static))
701 && !sess.is_nightly_build()
702 && find_gated_cfg(|cfg_sym| cfg_sym == name).is_some()
707 if let Some(value) = value {
708 Some(format!("{}=\"{}\"", name, value))
710 Some(name.to_string())
713 .collect::<Vec<String>>();
724 | StackProtectorStrategies
725 | TargetFeatures => {
726 codegen_backend.print(*req, sess);
728 // Any output here interferes with Cargo's parsing of other printed output
729 NativeStaticLibs => {}
736 /// Prints version information
737 pub fn version(binary: &str, matches: &getopts::Matches) {
738 let verbose = matches.opt_present("verbose");
740 println!("{} {}", binary, util::version_str().unwrap_or("unknown version"));
743 fn unw(x: Option<&str>) -> &str {
744 x.unwrap_or("unknown")
746 println!("binary: {}", binary);
747 println!("commit-hash: {}", unw(util::commit_hash_str()));
748 println!("commit-date: {}", unw(util::commit_date_str()));
749 println!("host: {}", config::host_triple());
750 println!("release: {}", unw(util::release_str()));
752 let debug_flags = matches.opt_strs("Z");
753 let backend_name = debug_flags.iter().find_map(|x| x.strip_prefix("codegen-backend="));
754 get_codegen_backend(&None, backend_name).print_version();
758 fn usage(verbose: bool, include_unstable_options: bool, nightly_build: bool) {
759 let groups = if verbose { config::rustc_optgroups() } else { config::rustc_short_optgroups() };
760 let mut options = getopts::Options::new();
761 for option in groups.iter().filter(|x| include_unstable_options || x.is_stable()) {
762 (option.apply)(&mut options);
764 let message = "Usage: rustc [OPTIONS] INPUT";
765 let nightly_help = if nightly_build {
766 "\n -Z help Print unstable compiler options"
770 let verbose_help = if verbose {
773 "\n --help -v Print the full set of options rustc accepts"
775 let at_path = if verbose {
776 " @path Read newline separated options from `path`\n"
781 "{options}{at_path}\nAdditional help:
782 -C help Print codegen options
784 Print 'lint' options and default settings{nightly}{verbose}\n",
785 options = options.usage(message),
787 nightly = nightly_help,
788 verbose = verbose_help
792 fn print_wall_help() {
795 The flag `-Wall` does not exist in `rustc`. Most useful lints are enabled by
796 default. Use `rustc -W help` to see all available lints. It's more common to put
797 warning settings in the crate root using `#![warn(LINT_NAME)]` instead of using
798 the command line flag directly.
803 /// Write to stdout lint command options, together with a list of all available lints
804 pub fn describe_lints(sess: &Session, lint_store: &LintStore, loaded_plugins: bool) {
807 Available lint options:
808 -W <foo> Warn about <foo>
812 -F <foo> Forbid <foo> \
813 (deny <foo> and all attempts to override)
818 fn sort_lints(sess: &Session, mut lints: Vec<&'static Lint>) -> Vec<&'static Lint> {
819 // The sort doesn't case-fold but it's doubtful we care.
820 lints.sort_by_cached_key(|x: &&Lint| (x.default_level(sess.edition()), x.name));
825 lints: Vec<(&'static str, Vec<LintId>, bool)>,
826 ) -> Vec<(&'static str, Vec<LintId>)> {
827 let mut lints: Vec<_> = lints.into_iter().map(|(x, y, _)| (x, y)).collect();
828 lints.sort_by_key(|l| l.0);
832 let (plugin, builtin): (Vec<_>, _) =
833 lint_store.get_lints().iter().cloned().partition(|&lint| lint.is_plugin);
834 let plugin = sort_lints(sess, plugin);
835 let builtin = sort_lints(sess, builtin);
837 let (plugin_groups, builtin_groups): (Vec<_>, _) =
838 lint_store.get_lint_groups().partition(|&(.., p)| p);
839 let plugin_groups = sort_lint_groups(plugin_groups);
840 let builtin_groups = sort_lint_groups(builtin_groups);
843 plugin.iter().chain(&builtin).map(|&s| s.name.chars().count()).max().unwrap_or(0);
844 let padded = |x: &str| {
845 let mut s = " ".repeat(max_name_len - x.chars().count());
850 println!("Lint checks provided by rustc:\n");
852 let print_lints = |lints: Vec<&Lint>| {
853 println!(" {} {:7.7} {}", padded("name"), "default", "meaning");
854 println!(" {} {:7.7} {}", padded("----"), "-------", "-------");
856 let name = lint.name_lower().replace('_', "-");
860 lint.default_level(sess.edition()).as_str(),
867 print_lints(builtin);
869 let max_name_len = max(
873 .chain(&builtin_groups)
874 .map(|&(s, _)| s.chars().count())
879 let padded = |x: &str| {
880 let mut s = " ".repeat(max_name_len - x.chars().count());
885 println!("Lint groups provided by rustc:\n");
887 let print_lint_groups = |lints: Vec<(&'static str, Vec<LintId>)>, all_warnings| {
888 println!(" {} sub-lints", padded("name"));
889 println!(" {} ---------", padded("----"));
892 println!(" {} all lints that are set to issue warnings", padded("warnings"));
895 for (name, to) in lints {
896 let name = name.to_lowercase().replace('_', "-");
899 .map(|x| x.to_string().replace('_', "-"))
900 .collect::<Vec<String>>()
902 println!(" {} {}", padded(&name), desc);
907 print_lint_groups(builtin_groups, true);
909 match (loaded_plugins, plugin.len(), plugin_groups.len()) {
910 (false, 0, _) | (false, _, 0) => {
911 println!("Lint tools like Clippy can provide additional lints and lint groups.");
913 (false, ..) => panic!("didn't load lint plugins but got them anyway!"),
914 (true, 0, 0) => println!("This crate does not load any lint plugins or lint groups."),
917 println!("Lint checks provided by plugins loaded by this crate:\n");
921 println!("Lint groups provided by plugins loaded by this crate:\n");
922 print_lint_groups(plugin_groups, false);
928 fn describe_debug_flags() {
929 println!("\nAvailable options:\n");
930 print_flag_list("-Z", config::Z_OPTIONS);
933 fn describe_codegen_flags() {
934 println!("\nAvailable codegen options:\n");
935 print_flag_list("-C", config::CG_OPTIONS);
938 pub fn print_flag_list<T>(
940 flag_list: &[(&'static str, T, &'static str, &'static str)],
942 let max_len = flag_list.iter().map(|&(name, _, _, _)| name.chars().count()).max().unwrap_or(0);
944 for &(name, _, _, desc) in flag_list {
946 " {} {:>width$}=val -- {}",
948 name.replace('_', "-"),
955 /// Process command line options. Emits messages as appropriate. If compilation
956 /// should continue, returns a getopts::Matches object parsed from args,
957 /// otherwise returns `None`.
959 /// The compiler's handling of options is a little complicated as it ties into
960 /// our stability story. The current intention of each compiler option is to
961 /// have one of two modes:
963 /// 1. An option is stable and can be used everywhere.
964 /// 2. An option is unstable, and can only be used on nightly.
966 /// Like unstable library and language features, however, unstable options have
967 /// always required a form of "opt in" to indicate that you're using them. This
968 /// provides the easy ability to scan a code base to check to see if anything
969 /// unstable is being used. Currently, this "opt in" is the `-Z` "zed" flag.
971 /// All options behind `-Z` are considered unstable by default. Other top-level
972 /// options can also be considered unstable, and they were unlocked through the
973 /// `-Z unstable-options` flag. Note that `-Z` remains to be the root of
974 /// instability in both cases, though.
976 /// So with all that in mind, the comments below have some more detail about the
977 /// contortions done here to get things to work out correctly.
978 pub fn handle_options(args: &[String]) -> Option<getopts::Matches> {
979 // Throw away the first argument, the name of the binary
980 let args = &args[1..];
983 // user did not write `-v` nor `-Z unstable-options`, so do not
984 // include that extra information.
986 rustc_feature::UnstableFeatures::from_environment(None).is_nightly_build();
987 usage(false, false, nightly_build);
991 // Parse with *all* options defined in the compiler, we don't worry about
992 // option stability here we just want to parse as much as possible.
993 let mut options = getopts::Options::new();
994 for option in config::rustc_optgroups() {
995 (option.apply)(&mut options);
997 let matches = options.parse(args).unwrap_or_else(|e| {
999 getopts::Fail::UnrecognizedOption(ref opt) => CG_OPTIONS
1001 .map(|&(name, ..)| ('C', name))
1002 .chain(Z_OPTIONS.iter().map(|&(name, ..)| ('Z', name)))
1003 .find(|&(_, name)| *opt == name.replace('_', "-"))
1004 .map(|(flag, _)| format!("{}. Did you mean `-{} {}`?", e, flag, opt)),
1007 early_error(ErrorOutputType::default(), &msg.unwrap_or_else(|| e.to_string()));
1010 // For all options we just parsed, we check a few aspects:
1012 // * If the option is stable, we're all good
1013 // * If the option wasn't passed, we're all good
1014 // * If `-Z unstable-options` wasn't passed (and we're not a -Z option
1015 // ourselves), then we require the `-Z unstable-options` flag to unlock
1016 // this option that was passed.
1017 // * If we're a nightly compiler, then unstable options are now unlocked, so
1018 // we're good to go.
1019 // * Otherwise, if we're an unstable option then we generate an error
1020 // (unstable option being used on stable)
1021 nightly_options::check_nightly_options(&matches, &config::rustc_optgroups());
1023 if matches.opt_present("h") || matches.opt_present("help") {
1024 // Only show unstable options in --help if we accept unstable options.
1025 let unstable_enabled = nightly_options::is_unstable_enabled(&matches);
1026 let nightly_build = nightly_options::match_is_nightly_build(&matches);
1027 usage(matches.opt_present("verbose"), unstable_enabled, nightly_build);
1031 // Handle the special case of -Wall.
1032 let wall = matches.opt_strs("W");
1033 if wall.iter().any(|x| *x == "all") {
1035 rustc_errors::FatalError.raise();
1038 // Don't handle -W help here, because we might first load plugins.
1039 let debug_flags = matches.opt_strs("Z");
1040 if debug_flags.iter().any(|x| *x == "help") {
1041 describe_debug_flags();
1045 let cg_flags = matches.opt_strs("C");
1047 if cg_flags.iter().any(|x| *x == "help") {
1048 describe_codegen_flags();
1052 if cg_flags.iter().any(|x| *x == "no-stack-check") {
1054 ErrorOutputType::default(),
1055 "the --no-stack-check flag is deprecated and does nothing",
1059 if cg_flags.iter().any(|x| *x == "passes=list") {
1060 let backend_name = debug_flags.iter().find_map(|x| x.strip_prefix("codegen-backend="));
1061 get_codegen_backend(&None, backend_name).print_passes();
1065 if matches.opt_present("version") {
1066 version("rustc", &matches);
1073 fn parse_crate_attrs<'a>(sess: &'a Session, input: &Input) -> PResult<'a, Vec<ast::Attribute>> {
1075 Input::File(ifile) => rustc_parse::parse_crate_attrs_from_file(ifile, &sess.parse_sess),
1076 Input::Str { name, input } => rustc_parse::parse_crate_attrs_from_source_str(
1084 /// Gets a list of extra command-line flags provided by the user, as strings.
1086 /// This function is used during ICEs to show more information useful for
1087 /// debugging, since some ICEs only happens with non-default compiler flags
1088 /// (and the users don't always report them).
1089 fn extra_compiler_flags() -> Option<(Vec<String>, bool)> {
1090 let mut args = env::args_os().map(|arg| arg.to_string_lossy().to_string()).peekable();
1092 let mut result = Vec::new();
1093 let mut excluded_cargo_defaults = false;
1094 while let Some(arg) = args.next() {
1095 if let Some(a) = ICE_REPORT_COMPILER_FLAGS.iter().find(|a| arg.starts_with(*a)) {
1096 let content = if arg.len() == a.len() {
1098 Some(arg) => arg.to_string(),
1101 } else if arg.get(a.len()..a.len() + 1) == Some("=") {
1102 arg[a.len() + 1..].to_string()
1104 arg[a.len()..].to_string()
1106 if ICE_REPORT_COMPILER_FLAGS_EXCLUDE.iter().any(|exc| content.starts_with(exc)) {
1107 excluded_cargo_defaults = true;
1109 result.push(a.to_string());
1110 match ICE_REPORT_COMPILER_FLAGS_STRIP_VALUE.iter().find(|s| content.starts_with(*s))
1112 Some(s) => result.push(s.to_string()),
1113 None => result.push(content),
1119 if !result.is_empty() { Some((result, excluded_cargo_defaults)) } else { None }
1122 /// Runs a closure and catches unwinds triggered by fatal errors.
1124 /// The compiler currently unwinds with a special sentinel value to abort
1125 /// compilation on fatal errors. This function catches that sentinel and turns
1126 /// the panic into a `Result` instead.
1127 pub fn catch_fatal_errors<F: FnOnce() -> R, R>(f: F) -> Result<R, ErrorGuaranteed> {
1128 catch_unwind(panic::AssertUnwindSafe(f)).map_err(|value| {
1129 if value.is::<rustc_errors::FatalErrorMarker>() {
1130 ErrorGuaranteed::unchecked_claim_error_was_emitted()
1132 panic::resume_unwind(value);
1137 /// Variant of `catch_fatal_errors` for the `interface::Result` return type
1138 /// that also computes the exit code.
1139 pub fn catch_with_exit_code(f: impl FnOnce() -> interface::Result<()>) -> i32 {
1140 let result = catch_fatal_errors(f).and_then(|result| result);
1142 Ok(()) => EXIT_SUCCESS,
1143 Err(_) => EXIT_FAILURE,
1147 static DEFAULT_HOOK: LazyLock<Box<dyn Fn(&panic::PanicInfo<'_>) + Sync + Send + 'static>> =
1149 let hook = panic::take_hook();
1150 panic::set_hook(Box::new(|info| {
1151 // Invoke the default handler, which prints the actual panic message and optionally a backtrace
1152 (*DEFAULT_HOOK)(info);
1154 // Separate the output with an empty line
1157 // Print the ICE message
1158 report_ice(info, BUG_REPORT_URL);
1163 /// Prints the ICE message, including query stack, but without backtrace.
1165 /// The message will point the user at `bug_report_url` to report the ICE.
1167 /// When `install_ice_hook` is called, this function will be called as the panic
1169 pub fn report_ice(info: &panic::PanicInfo<'_>, bug_report_url: &str) {
1170 let fallback_bundle =
1171 rustc_errors::fallback_fluent_bundle(rustc_errors::DEFAULT_LOCALE_RESOURCES, false);
1172 let emitter = Box::new(rustc_errors::emitter::EmitterWriter::stderr(
1173 rustc_errors::ColorConfig::Auto,
1182 let handler = rustc_errors::Handler::with_emitter(true, None, emitter);
1184 // a .span_bug or .bug call has already printed what
1185 // it wants to print.
1186 if !info.payload().is::<rustc_errors::ExplicitBug>() {
1187 let mut d = rustc_errors::Diagnostic::new(rustc_errors::Level::Bug, "unexpected panic");
1188 handler.emit_diagnostic(&mut d);
1191 let mut xs: Vec<Cow<'static, str>> = vec![
1192 "the compiler unexpectedly panicked. this is a bug.".into(),
1193 format!("we would appreciate a bug report: {}", bug_report_url).into(),
1195 "rustc {} running on {}",
1196 util::version_str().unwrap_or("unknown_version"),
1197 config::host_triple()
1202 if let Some((flags, excluded_cargo_defaults)) = extra_compiler_flags() {
1203 xs.push(format!("compiler flags: {}", flags.join(" ")).into());
1205 if excluded_cargo_defaults {
1206 xs.push("some of the compiler flags provided by cargo are hidden".into());
1211 handler.note_without_error(note.as_ref());
1214 // If backtraces are enabled, also print the query stack
1215 let backtrace = env::var_os("RUST_BACKTRACE").map_or(false, |x| &x != "0");
1217 let num_frames = if backtrace { None } else { Some(2) };
1219 interface::try_print_query_stack(&handler, num_frames);
1223 if env::var("RUSTC_BREAK_ON_ICE").is_ok() {
1224 // Trigger a debugger if we crashed during bootstrap
1225 winapi::um::debugapi::DebugBreak();
1230 /// Installs a panic hook that will print the ICE message on unexpected panics.
1232 /// A custom rustc driver can skip calling this to set up a custom ICE hook.
1233 pub fn install_ice_hook() {
1234 // If the user has not explicitly overridden "RUST_BACKTRACE", then produce
1235 // full backtraces. When a compiler ICE happens, we want to gather
1236 // as much information as possible to present in the issue opened
1237 // by the user. Compiler developers and other rustc users can
1238 // opt in to less-verbose backtraces by manually setting "RUST_BACKTRACE"
1239 // (e.g. `RUST_BACKTRACE=1`)
1240 if std::env::var("RUST_BACKTRACE").is_err() {
1241 std::env::set_var("RUST_BACKTRACE", "full");
1243 LazyLock::force(&DEFAULT_HOOK);
1246 /// This allows tools to enable rust logging without having to magically match rustc's
1247 /// tracing crate version.
1248 pub fn init_rustc_env_logger() {
1249 if let Err(error) = rustc_log::init_rustc_env_logger() {
1250 early_error(ErrorOutputType::default(), &error.to_string());
1254 /// This allows tools to enable rust logging without having to magically match rustc's
1255 /// tracing crate version. In contrast to `init_rustc_env_logger` it allows you to choose an env var
1256 /// other than `RUSTC_LOG`.
1257 pub fn init_env_logger(env: &str) {
1258 if let Err(error) = rustc_log::init_env_logger(env) {
1259 early_error(ErrorOutputType::default(), &error.to_string());
1263 #[cfg(all(unix, any(target_env = "gnu", target_os = "macos")))]
1264 mod signal_handler {
1266 fn backtrace_symbols_fd(
1267 buffer: *const *mut libc::c_void,
1273 extern "C" fn print_stack_trace(_: libc::c_int) {
1274 const MAX_FRAMES: usize = 256;
1275 static mut STACK_TRACE: [*mut libc::c_void; MAX_FRAMES] =
1276 [std::ptr::null_mut(); MAX_FRAMES];
1278 let depth = libc::backtrace(STACK_TRACE.as_mut_ptr(), MAX_FRAMES as i32);
1282 backtrace_symbols_fd(STACK_TRACE.as_ptr(), depth, 2);
1286 // When an error signal (such as SIGABRT or SIGSEGV) is delivered to the
1287 // process, print a stack trace and then exit.
1288 pub(super) fn install() {
1290 const ALT_STACK_SIZE: usize = libc::MINSIGSTKSZ + 64 * 1024;
1291 let mut alt_stack: libc::stack_t = std::mem::zeroed();
1293 std::alloc::alloc(std::alloc::Layout::from_size_align(ALT_STACK_SIZE, 1).unwrap())
1294 as *mut libc::c_void;
1295 alt_stack.ss_size = ALT_STACK_SIZE;
1296 libc::sigaltstack(&alt_stack, std::ptr::null_mut());
1298 let mut sa: libc::sigaction = std::mem::zeroed();
1299 sa.sa_sigaction = print_stack_trace as libc::sighandler_t;
1300 sa.sa_flags = libc::SA_NODEFER | libc::SA_RESETHAND | libc::SA_ONSTACK;
1301 libc::sigemptyset(&mut sa.sa_mask);
1302 libc::sigaction(libc::SIGSEGV, &sa, std::ptr::null_mut());
1307 #[cfg(not(all(unix, any(target_env = "gnu", target_os = "macos"))))]
1308 mod signal_handler {
1309 pub(super) fn install() {}
1312 pub fn main() -> ! {
1313 let start_time = Instant::now();
1314 let start_rss = get_resident_set_size();
1315 init_rustc_env_logger();
1316 signal_handler::install();
1317 let mut callbacks = TimePassesCallbacks::default();
1319 let exit_code = catch_with_exit_code(|| {
1320 let args = env::args_os()
1323 arg.into_string().unwrap_or_else(|arg| {
1325 ErrorOutputType::default(),
1326 &format!("argument {} is not valid Unicode: {:?}", i, arg),
1330 .collect::<Vec<_>>();
1331 RunCompiler::new(&args, &mut callbacks).run()
1334 if callbacks.time_passes {
1335 let end_rss = get_resident_set_size();
1336 print_time_passes_entry("total", start_time.elapsed(), start_rss, end_rss);
1339 process::exit(exit_code)