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 #![cfg_attr(not(bootstrap), 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::{ErrorReported, 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_serialize::json::ToJson;
33 use rustc_session::config::{nightly_options, CG_OPTIONS, DB_OPTIONS};
34 use rustc_session::config::{ErrorOutputType, Input, OutputType, PrintRequest, TrimmedDefPaths};
35 use rustc_session::cstore::MetadataLoader;
36 use rustc_session::getopts;
37 use rustc_session::lint::{Lint, LintId};
38 use rustc_session::{config, DiagnosticOutput, Session};
39 use rustc_session::{early_error, early_error_no_abort, early_warn};
40 use rustc_span::source_map::{FileLoader, FileName};
41 use rustc_span::symbol::sym;
45 use std::default::Default;
47 use std::ffi::OsString;
49 use std::io::{self, Read, Write};
50 use std::lazy::SyncLazy;
51 use std::panic::{self, catch_unwind};
52 use std::path::PathBuf;
53 use std::process::{self, Command, Stdio};
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, ErrorReported>, 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()
127 && (config.opts.debugging_opts.time_passes || config.opts.debugging_opts.time);
128 config.opts.trimmed_def_paths = TrimmedDefPaths::GoodPath;
132 pub fn diagnostics_registry() -> Registry {
133 Registry::new(rustc_error_codes::DIAGNOSTICS)
136 /// This is the primary entry point for rustc.
137 pub struct RunCompiler<'a, 'b> {
138 at_args: &'a [String],
139 callbacks: &'b mut (dyn Callbacks + Send),
140 file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
141 emitter: Option<Box<dyn Write + Send>>,
142 make_codegen_backend:
143 Option<Box<dyn FnOnce(&config::Options) -> Box<dyn CodegenBackend> + Send>>,
146 impl<'a, 'b> RunCompiler<'a, 'b> {
147 pub fn new(at_args: &'a [String], callbacks: &'b mut (dyn Callbacks + Send)) -> Self {
148 Self { at_args, callbacks, file_loader: None, emitter: None, make_codegen_backend: None }
151 /// Set a custom codegen backend.
154 pub fn set_make_codegen_backend(
156 make_codegen_backend: Option<
157 Box<dyn FnOnce(&config::Options) -> Box<dyn CodegenBackend> + Send>,
160 self.make_codegen_backend = make_codegen_backend;
164 /// Emit diagnostics to the specified location.
167 pub fn set_emitter(&mut self, emitter: Option<Box<dyn Write + Send>>) -> &mut Self {
168 self.emitter = emitter;
172 /// Load files from sources other than the file system.
175 pub fn set_file_loader(
177 file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
179 self.file_loader = file_loader;
183 /// Parse args and run the compiler.
184 pub fn run(self) -> interface::Result<()> {
190 self.make_codegen_backend,
196 callbacks: &mut (dyn Callbacks + Send),
197 file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
198 emitter: Option<Box<dyn Write + Send>>,
199 make_codegen_backend: Option<
200 Box<dyn FnOnce(&config::Options) -> Box<dyn CodegenBackend> + Send>,
202 ) -> interface::Result<()> {
203 let args = args::arg_expand_all(at_args);
205 let diagnostic_output = emitter.map_or(DiagnosticOutput::Default, DiagnosticOutput::Raw);
206 let matches = match handle_options(&args) {
207 Some(matches) => matches,
208 None => return Ok(()),
211 let sopts = config::build_session_options(&matches);
213 if let Some(ref code) = matches.opt_str("explain") {
214 handle_explain(diagnostics_registry(), code, sopts.error_format);
218 let cfg = interface::parse_cfgspecs(matches.opt_strs("cfg"));
219 let (odir, ofile) = make_output(&matches);
220 let mut config = interface::Config {
223 input: Input::File(PathBuf::new()),
230 lint_caps: Default::default(),
231 parse_sess_created: None,
232 register_lints: None,
233 override_queries: None,
234 make_codegen_backend,
235 registry: diagnostics_registry(),
238 match make_input(config.opts.error_format, &matches.free) {
239 Err(ErrorReported) => return Err(ErrorReported),
240 Ok(Some((input, input_file_path))) => {
241 config.input = input;
242 config.input_path = input_file_path;
244 callbacks.config(&mut config);
246 Ok(None) => match matches.free.len() {
248 callbacks.config(&mut config);
249 interface::run_compiler(config, |compiler| {
250 let sopts = &compiler.session().opts;
251 if sopts.describe_lints {
252 let mut lint_store = rustc_lint::new_lint_store(
253 sopts.debugging_opts.no_interleave_lints,
254 compiler.session().unstable_options(),
256 let registered_lints =
257 if let Some(register_lints) = compiler.register_lints() {
258 register_lints(compiler.session(), &mut lint_store);
263 describe_lints(compiler.session(), &lint_store, registered_lints);
266 let should_stop = RustcDefaultCalls::print_crate_info(
267 &***compiler.codegen_backend(),
270 compiler.output_dir(),
271 compiler.output_file(),
272 compiler.temps_dir(),
275 if should_stop == Compilation::Stop {
278 early_error(sopts.error_format, "no input filename given")
282 1 => panic!("make_input should have provided valid inputs"),
284 config.opts.error_format,
286 "multiple input filenames provided (first two filenames are `{}` and `{}`)",
287 matches.free[0], matches.free[1],
293 interface::run_compiler(config, |compiler| {
294 let sess = compiler.session();
295 let should_stop = RustcDefaultCalls::print_crate_info(
296 &***compiler.codegen_backend(),
298 Some(compiler.input()),
299 compiler.output_dir(),
300 compiler.output_file(),
301 compiler.temps_dir(),
304 RustcDefaultCalls::list_metadata(
306 &*compiler.codegen_backend().metadata_loader(),
310 .and_then(|| RustcDefaultCalls::try_process_rlink(sess, compiler));
312 if should_stop == Compilation::Stop {
313 return sess.compile_status();
316 let linker = compiler.enter(|queries| {
317 let early_exit = || sess.compile_status().map(|_| None);
320 if let Some(ppm) = &sess.opts.pretty {
321 if ppm.needs_ast_map() {
322 let expanded_crate = queries.expansion()?.peek().0.clone();
323 queries.global_ctxt()?.peek_mut().enter(|tcx| {
324 pretty::print_after_hir_lowering(
329 compiler.output_file().as_ref().map(|p| &**p),
334 let krate = queries.parse()?.take();
335 pretty::print_after_parsing(
340 compiler.output_file().as_ref().map(|p| &**p),
343 trace!("finished pretty-printing");
347 if callbacks.after_parsing(compiler, queries) == Compilation::Stop {
351 if sess.opts.debugging_opts.parse_only
352 || sess.opts.debugging_opts.show_span.is_some()
353 || sess.opts.debugging_opts.ast_json_noexpand
359 let (_, lint_store) = &*queries.register_plugins()?.peek();
361 // Lint plugins are registered; now we can process command line flags.
362 if sess.opts.describe_lints {
363 describe_lints(sess, lint_store, true);
368 queries.expansion()?;
369 if callbacks.after_expansion(compiler, queries) == Compilation::Stop {
373 queries.prepare_outputs()?;
375 if sess.opts.output_types.contains_key(&OutputType::DepInfo)
376 && sess.opts.output_types.len() == 1
381 queries.global_ctxt()?;
383 if sess.opts.debugging_opts.no_analysis || sess.opts.debugging_opts.ast_json {
387 queries.global_ctxt()?.peek_mut().enter(|tcx| {
388 let result = tcx.analysis(());
389 if sess.opts.debugging_opts.save_analysis {
390 let crate_name = queries.crate_name()?.peek().clone();
391 sess.time("save_analysis", || {
398 compiler.output_dir().as_ref().map(|p| &**p),
407 if callbacks.after_analysis(compiler, queries) == Compilation::Stop {
411 queries.ongoing_codegen()?;
413 if sess.opts.debugging_opts.print_type_sizes {
414 sess.code_stats.print_type_sizes();
417 let linker = queries.linker()?;
421 if let Some(linker) = linker {
422 let _timer = sess.timer("link");
426 if sess.opts.debugging_opts.perf_stats {
427 sess.print_perf_stats();
430 if sess.opts.debugging_opts.print_fuel.is_some() {
432 "Fuel used by {}: {}",
433 sess.opts.debugging_opts.print_fuel.as_ref().unwrap(),
434 sess.print_fuel.load(SeqCst)
443 pub fn set_sigpipe_handler() {
445 // Set the SIGPIPE signal handler, so that an EPIPE
446 // will cause rustc to terminate, as expected.
447 assert_ne!(libc::signal(libc::SIGPIPE, libc::SIG_DFL), libc::SIG_ERR);
452 pub fn set_sigpipe_handler() {}
454 // Extract output directory and file from matches.
455 fn make_output(matches: &getopts::Matches) -> (Option<PathBuf>, Option<PathBuf>) {
456 let odir = matches.opt_str("out-dir").map(|o| PathBuf::from(&o));
457 let ofile = matches.opt_str("o").map(|o| PathBuf::from(&o));
461 // Extract input (string or file and optional path) from matches.
463 error_format: ErrorOutputType,
464 free_matches: &[String],
465 ) -> Result<Option<(Input, Option<PathBuf>)>, ErrorReported> {
466 if free_matches.len() == 1 {
467 let ifile = &free_matches[0];
469 let mut src = String::new();
470 if io::stdin().read_to_string(&mut src).is_err() {
471 // Immediately stop compilation if there was an issue reading
472 // the input (for example if the input stream is not UTF-8).
473 early_error_no_abort(
475 "couldn't read from stdin, as it did not contain valid UTF-8",
477 return Err(ErrorReported);
479 if let Ok(path) = env::var("UNSTABLE_RUSTDOC_TEST_PATH") {
480 let line = env::var("UNSTABLE_RUSTDOC_TEST_LINE").expect(
481 "when UNSTABLE_RUSTDOC_TEST_PATH is set \
482 UNSTABLE_RUSTDOC_TEST_LINE also needs to be set",
484 let line = isize::from_str_radix(&line, 10)
485 .expect("UNSTABLE_RUSTDOC_TEST_LINE needs to be an number");
486 let file_name = FileName::doc_test_source_code(PathBuf::from(path), line);
487 Ok(Some((Input::Str { name: file_name, input: src }, None)))
489 Ok(Some((Input::Str { name: FileName::anon_source_code(&src), input: src }, None)))
492 Ok(Some((Input::File(PathBuf::from(ifile)), Some(PathBuf::from(ifile)))))
499 /// Whether to stop or continue compilation.
500 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
501 pub enum Compilation {
507 pub fn and_then<F: FnOnce() -> Compilation>(self, next: F) -> Compilation {
509 Compilation::Stop => Compilation::Stop,
510 Compilation::Continue => next(),
515 /// CompilerCalls instance for a regular rustc build.
516 #[derive(Copy, Clone)]
517 pub struct RustcDefaultCalls;
519 fn handle_explain(registry: Registry, code: &str, output: ErrorOutputType) {
520 let upper_cased_code = code.to_ascii_uppercase();
521 let normalised = if upper_cased_code.starts_with('E') {
524 format!("E{0:0>4}", code)
526 match registry.try_find_description(&normalised) {
527 Ok(Some(description)) => {
528 let mut is_in_code_block = false;
529 let mut text = String::new();
530 // Slice off the leading newline and print.
531 for line in description.lines() {
533 line.find(|c: char| !c.is_whitespace()).unwrap_or_else(|| line.len());
534 let dedented_line = &line[indent_level..];
535 if dedented_line.starts_with("```") {
536 is_in_code_block = !is_in_code_block;
537 text.push_str(&line[..(indent_level + 3)]);
538 } else if is_in_code_block && dedented_line.starts_with("# ") {
546 show_content_with_pager(&text);
552 early_error(output, &format!("no extended information for {}", code));
554 Err(InvalidErrorCode) => {
555 early_error(output, &format!("{} is not a valid error code", code));
560 fn show_content_with_pager(content: &str) {
561 let pager_name = env::var_os("PAGER").unwrap_or_else(|| {
562 if cfg!(windows) { OsString::from("more.com") } else { OsString::from("less") }
565 let mut fallback_to_println = false;
567 match Command::new(pager_name).stdin(Stdio::piped()).spawn() {
569 if let Some(pipe) = pager.stdin.as_mut() {
570 if pipe.write_all(content.as_bytes()).is_err() {
571 fallback_to_println = true;
575 if pager.wait().is_err() {
576 fallback_to_println = true;
580 fallback_to_println = true;
584 // If pager fails for whatever reason, we should still print the content
585 // to standard output
586 if fallback_to_println {
587 print!("{}", content);
591 impl RustcDefaultCalls {
592 pub fn try_process_rlink(sess: &Session, compiler: &interface::Compiler) -> Compilation {
593 if sess.opts.debugging_opts.link_only {
594 if let Input::File(file) = compiler.input() {
595 // FIXME: #![crate_type] and #![crate_name] support not implemented yet
596 sess.init_crate_types(collect_crate_types(sess, &[]));
597 let outputs = compiler.build_output_filenames(sess, &[]);
598 let rlink_data = fs::read(file).unwrap_or_else(|err| {
599 sess.fatal(&format!("failed to read rlink file: {}", err));
601 let mut decoder = rustc_serialize::opaque::Decoder::new(&rlink_data, 0);
602 let codegen_results: CodegenResults =
603 rustc_serialize::Decodable::decode(&mut decoder);
604 let result = compiler.codegen_backend().link(sess, codegen_results, &outputs);
605 abort_on_err(result, sess);
607 sess.fatal("rlink must be a file")
611 Compilation::Continue
615 pub fn list_metadata(
617 metadata_loader: &dyn MetadataLoader,
620 if sess.opts.debugging_opts.ls {
622 Input::File(ref ifile) => {
623 let path = &(*ifile);
624 let mut v = Vec::new();
625 locator::list_file_metadata(&sess.target, path, metadata_loader, &mut v)
627 println!("{}", String::from_utf8(v).unwrap());
629 Input::Str { .. } => {
630 early_error(ErrorOutputType::default(), "cannot list metadata for stdin");
633 return Compilation::Stop;
636 Compilation::Continue
640 codegen_backend: &dyn CodegenBackend,
642 input: Option<&Input>,
643 odir: &Option<PathBuf>,
644 ofile: &Option<PathBuf>,
645 temps_dir: &Option<PathBuf>,
647 use rustc_session::config::PrintRequest::*;
648 // NativeStaticLibs and LinkArgs are special - printed during linking
649 // (empty iterator returns true)
650 if sess.opts.prints.iter().all(|&p| p == NativeStaticLibs || p == LinkArgs) {
651 return Compilation::Continue;
654 let attrs = match input {
657 let result = parse_crate_attrs(sess, input);
659 Ok(attrs) => Some(attrs),
660 Err(mut parse_error) => {
662 return Compilation::Stop;
667 for req in &sess.opts.prints {
671 rustc_target::spec::TARGETS.iter().copied().collect::<Vec<_>>();
672 targets.sort_unstable();
673 println!("{}", targets.join("\n"));
675 Sysroot => println!("{}", sess.sysroot.display()),
676 TargetLibdir => println!("{}", sess.target_tlib_path.dir.display()),
677 TargetSpec => println!("{}", sess.target.to_json().pretty()),
678 FileNames | CrateName => {
679 let input = input.unwrap_or_else(|| {
680 early_error(ErrorOutputType::default(), "no input file provided")
682 let attrs = attrs.as_ref().unwrap();
683 let t_outputs = rustc_interface::util::build_output_filenames(
684 input, odir, ofile, temps_dir, attrs, sess,
686 let id = rustc_session::output::find_crate_name(sess, attrs, input);
687 if *req == PrintRequest::CrateName {
691 let crate_types = collect_crate_types(sess, attrs);
692 for &style in &crate_types {
694 rustc_session::output::filename_for_input(sess, style, &id, &t_outputs);
695 println!("{}", fname.file_name().unwrap().to_string_lossy());
703 .filter_map(|&(name, value)| {
704 // Note that crt-static is a specially recognized cfg
705 // directive that's printed out here as part of
706 // rust-lang/rust#37406, but in general the
707 // `target_feature` cfg is gated under
708 // rust-lang/rust#29717. For now this is just
709 // specifically allowing the crt-static cfg and that's
710 // it, this is intended to get into Cargo and then go
711 // through to build scripts.
712 if (name != sym::target_feature || value != Some(sym::crt_dash_static))
713 && !sess.is_nightly_build()
714 && find_gated_cfg(|cfg_sym| cfg_sym == name).is_some()
719 if let Some(value) = value {
720 Some(format!("{}=\"{}\"", name, value))
722 Some(name.to_string())
725 .collect::<Vec<String>>();
736 | StackProtectorStrategies
737 | TargetFeatures => {
738 codegen_backend.print(*req, sess);
740 // Any output here interferes with Cargo's parsing of other printed output
741 NativeStaticLibs => {}
749 /// Prints version information
750 pub fn version(binary: &str, matches: &getopts::Matches) {
751 let verbose = matches.opt_present("verbose");
753 println!("{} {}", binary, util::version_str().unwrap_or("unknown version"));
756 fn unw(x: Option<&str>) -> &str {
757 x.unwrap_or("unknown")
759 println!("binary: {}", binary);
760 println!("commit-hash: {}", unw(util::commit_hash_str()));
761 println!("commit-date: {}", unw(util::commit_date_str()));
762 println!("host: {}", config::host_triple());
763 println!("release: {}", unw(util::release_str()));
765 let debug_flags = matches.opt_strs("Z");
766 let backend_name = debug_flags.iter().find_map(|x| x.strip_prefix("codegen-backend="));
767 get_codegen_backend(&None, backend_name).print_version();
771 fn usage(verbose: bool, include_unstable_options: bool, nightly_build: bool) {
772 let groups = if verbose { config::rustc_optgroups() } else { config::rustc_short_optgroups() };
773 let mut options = getopts::Options::new();
774 for option in groups.iter().filter(|x| include_unstable_options || x.is_stable()) {
775 (option.apply)(&mut options);
777 let message = "Usage: rustc [OPTIONS] INPUT";
778 let nightly_help = if nightly_build {
779 "\n -Z help Print unstable compiler options"
783 let verbose_help = if verbose {
786 "\n --help -v Print the full set of options rustc accepts"
788 let at_path = if verbose {
789 " @path Read newline separated options from `path`\n"
794 "{options}{at_path}\nAdditional help:
795 -C help Print codegen options
797 Print 'lint' options and default settings{nightly}{verbose}\n",
798 options = options.usage(message),
800 nightly = nightly_help,
801 verbose = verbose_help
805 fn print_wall_help() {
808 The flag `-Wall` does not exist in `rustc`. Most useful lints are enabled by
809 default. Use `rustc -W help` to see all available lints. It's more common to put
810 warning settings in the crate root using `#![warn(LINT_NAME)]` instead of using
811 the command line flag directly.
816 /// Write to stdout lint command options, together with a list of all available lints
817 pub fn describe_lints(sess: &Session, lint_store: &LintStore, loaded_plugins: bool) {
820 Available lint options:
821 -W <foo> Warn about <foo>
825 -F <foo> Forbid <foo> \
826 (deny <foo> and all attempts to override)
831 fn sort_lints(sess: &Session, mut lints: Vec<&'static Lint>) -> Vec<&'static Lint> {
832 // The sort doesn't case-fold but it's doubtful we care.
833 lints.sort_by_cached_key(|x: &&Lint| (x.default_level(sess.edition()), x.name));
838 lints: Vec<(&'static str, Vec<LintId>, bool)>,
839 ) -> Vec<(&'static str, Vec<LintId>)> {
840 let mut lints: Vec<_> = lints.into_iter().map(|(x, y, _)| (x, y)).collect();
841 lints.sort_by_key(|l| l.0);
845 let (plugin, builtin): (Vec<_>, _) =
846 lint_store.get_lints().iter().cloned().partition(|&lint| lint.is_plugin);
847 let plugin = sort_lints(sess, plugin);
848 let builtin = sort_lints(sess, builtin);
850 let (plugin_groups, builtin_groups): (Vec<_>, _) =
851 lint_store.get_lint_groups().partition(|&(.., p)| p);
852 let plugin_groups = sort_lint_groups(plugin_groups);
853 let builtin_groups = sort_lint_groups(builtin_groups);
856 plugin.iter().chain(&builtin).map(|&s| s.name.chars().count()).max().unwrap_or(0);
857 let padded = |x: &str| {
858 let mut s = " ".repeat(max_name_len - x.chars().count());
863 println!("Lint checks provided by rustc:\n");
864 println!(" {} {:7.7} {}", padded("name"), "default", "meaning");
865 println!(" {} {:7.7} {}", padded("----"), "-------", "-------");
867 let print_lints = |lints: Vec<&Lint>| {
869 let name = lint.name_lower().replace('_', "-");
873 lint.default_level(sess.edition()).as_str(),
880 print_lints(builtin);
882 let max_name_len = max(
886 .chain(&builtin_groups)
887 .map(|&(s, _)| s.chars().count())
892 let padded = |x: &str| {
893 let mut s = " ".repeat(max_name_len - x.chars().count());
898 println!("Lint groups provided by rustc:\n");
899 println!(" {} sub-lints", padded("name"));
900 println!(" {} ---------", padded("----"));
901 println!(" {} all lints that are set to issue warnings", padded("warnings"));
903 let print_lint_groups = |lints: Vec<(&'static str, Vec<LintId>)>| {
904 for (name, to) in lints {
905 let name = name.to_lowercase().replace('_', "-");
908 .map(|x| x.to_string().replace('_', "-"))
909 .collect::<Vec<String>>()
911 println!(" {} {}", padded(&name), desc);
916 print_lint_groups(builtin_groups);
918 match (loaded_plugins, plugin.len(), plugin_groups.len()) {
919 (false, 0, _) | (false, _, 0) => {
920 println!("Lint tools like Clippy can provide additional lints and lint groups.");
922 (false, ..) => panic!("didn't load lint plugins but got them anyway!"),
923 (true, 0, 0) => println!("This crate does not load any lint plugins or lint groups."),
926 println!("Lint checks provided by plugins loaded by this crate:\n");
930 println!("Lint groups provided by plugins loaded by this crate:\n");
931 print_lint_groups(plugin_groups);
937 fn describe_debug_flags() {
938 println!("\nAvailable options:\n");
939 print_flag_list("-Z", config::DB_OPTIONS);
942 fn describe_codegen_flags() {
943 println!("\nAvailable codegen options:\n");
944 print_flag_list("-C", config::CG_OPTIONS);
947 fn print_flag_list<T>(
949 flag_list: &[(&'static str, T, &'static str, &'static str)],
951 let max_len = flag_list.iter().map(|&(name, _, _, _)| name.chars().count()).max().unwrap_or(0);
953 for &(name, _, _, desc) in flag_list {
955 " {} {:>width$}=val -- {}",
957 name.replace('_', "-"),
964 /// Process command line options. Emits messages as appropriate. If compilation
965 /// should continue, returns a getopts::Matches object parsed from args,
966 /// otherwise returns `None`.
968 /// The compiler's handling of options is a little complicated as it ties into
969 /// our stability story. The current intention of each compiler option is to
970 /// have one of two modes:
972 /// 1. An option is stable and can be used everywhere.
973 /// 2. An option is unstable, and can only be used on nightly.
975 /// Like unstable library and language features, however, unstable options have
976 /// always required a form of "opt in" to indicate that you're using them. This
977 /// provides the easy ability to scan a code base to check to see if anything
978 /// unstable is being used. Currently, this "opt in" is the `-Z` "zed" flag.
980 /// All options behind `-Z` are considered unstable by default. Other top-level
981 /// options can also be considered unstable, and they were unlocked through the
982 /// `-Z unstable-options` flag. Note that `-Z` remains to be the root of
983 /// instability in both cases, though.
985 /// So with all that in mind, the comments below have some more detail about the
986 /// contortions done here to get things to work out correctly.
987 pub fn handle_options(args: &[String]) -> Option<getopts::Matches> {
988 // Throw away the first argument, the name of the binary
989 let args = &args[1..];
992 // user did not write `-v` nor `-Z unstable-options`, so do not
993 // include that extra information.
995 rustc_feature::UnstableFeatures::from_environment(None).is_nightly_build();
996 usage(false, false, nightly_build);
1000 // Parse with *all* options defined in the compiler, we don't worry about
1001 // option stability here we just want to parse as much as possible.
1002 let mut options = getopts::Options::new();
1003 for option in config::rustc_optgroups() {
1004 (option.apply)(&mut options);
1006 let matches = options.parse(args).unwrap_or_else(|e| {
1008 getopts::Fail::UnrecognizedOption(ref opt) => CG_OPTIONS
1010 .map(|&(name, ..)| ('C', name))
1011 .chain(DB_OPTIONS.iter().map(|&(name, ..)| ('Z', name)))
1012 .find(|&(_, name)| *opt == name.replace('_', "-"))
1013 .map(|(flag, _)| format!("{}. Did you mean `-{} {}`?", e, flag, opt)),
1016 early_error(ErrorOutputType::default(), &msg.unwrap_or_else(|| e.to_string()));
1019 // For all options we just parsed, we check a few aspects:
1021 // * If the option is stable, we're all good
1022 // * If the option wasn't passed, we're all good
1023 // * If `-Z unstable-options` wasn't passed (and we're not a -Z option
1024 // ourselves), then we require the `-Z unstable-options` flag to unlock
1025 // this option that was passed.
1026 // * If we're a nightly compiler, then unstable options are now unlocked, so
1027 // we're good to go.
1028 // * Otherwise, if we're an unstable option then we generate an error
1029 // (unstable option being used on stable)
1030 nightly_options::check_nightly_options(&matches, &config::rustc_optgroups());
1032 if matches.opt_present("h") || matches.opt_present("help") {
1033 // Only show unstable options in --help if we accept unstable options.
1034 let unstable_enabled = nightly_options::is_unstable_enabled(&matches);
1035 let nightly_build = nightly_options::match_is_nightly_build(&matches);
1036 usage(matches.opt_present("verbose"), unstable_enabled, nightly_build);
1040 // Handle the special case of -Wall.
1041 let wall = matches.opt_strs("W");
1042 if wall.iter().any(|x| *x == "all") {
1044 rustc_errors::FatalError.raise();
1047 // Don't handle -W help here, because we might first load plugins.
1048 let debug_flags = matches.opt_strs("Z");
1049 if debug_flags.iter().any(|x| *x == "help") {
1050 describe_debug_flags();
1054 let cg_flags = matches.opt_strs("C");
1056 if cg_flags.iter().any(|x| *x == "help") {
1057 describe_codegen_flags();
1061 if cg_flags.iter().any(|x| *x == "no-stack-check") {
1063 ErrorOutputType::default(),
1064 "the --no-stack-check flag is deprecated and does nothing",
1068 if cg_flags.iter().any(|x| *x == "passes=list") {
1069 let backend_name = debug_flags.iter().find_map(|x| {
1070 if x.starts_with("codegen-backend=") {
1071 Some(&x["codegen-backends=".len()..])
1076 get_codegen_backend(&None, backend_name).print_passes();
1080 if matches.opt_present("version") {
1081 version("rustc", &matches);
1088 fn parse_crate_attrs<'a>(sess: &'a Session, input: &Input) -> PResult<'a, Vec<ast::Attribute>> {
1090 Input::File(ifile) => rustc_parse::parse_crate_attrs_from_file(ifile, &sess.parse_sess),
1091 Input::Str { name, input } => rustc_parse::parse_crate_attrs_from_source_str(
1099 /// Gets a list of extra command-line flags provided by the user, as strings.
1101 /// This function is used during ICEs to show more information useful for
1102 /// debugging, since some ICEs only happens with non-default compiler flags
1103 /// (and the users don't always report them).
1104 fn extra_compiler_flags() -> Option<(Vec<String>, bool)> {
1105 let mut args = env::args_os().map(|arg| arg.to_string_lossy().to_string()).peekable();
1107 let mut result = Vec::new();
1108 let mut excluded_cargo_defaults = false;
1109 while let Some(arg) = args.next() {
1110 if let Some(a) = ICE_REPORT_COMPILER_FLAGS.iter().find(|a| arg.starts_with(*a)) {
1111 let content = if arg.len() == a.len() {
1113 Some(arg) => arg.to_string(),
1116 } else if arg.get(a.len()..a.len() + 1) == Some("=") {
1117 arg[a.len() + 1..].to_string()
1119 arg[a.len()..].to_string()
1121 if ICE_REPORT_COMPILER_FLAGS_EXCLUDE.iter().any(|exc| content.starts_with(exc)) {
1122 excluded_cargo_defaults = true;
1124 result.push(a.to_string());
1125 match ICE_REPORT_COMPILER_FLAGS_STRIP_VALUE.iter().find(|s| content.starts_with(*s))
1127 Some(s) => result.push(s.to_string()),
1128 None => result.push(content),
1134 if !result.is_empty() { Some((result, excluded_cargo_defaults)) } else { None }
1137 /// Runs a closure and catches unwinds triggered by fatal errors.
1139 /// The compiler currently unwinds with a special sentinel value to abort
1140 /// compilation on fatal errors. This function catches that sentinel and turns
1141 /// the panic into a `Result` instead.
1142 pub fn catch_fatal_errors<F: FnOnce() -> R, R>(f: F) -> Result<R, ErrorReported> {
1143 catch_unwind(panic::AssertUnwindSafe(f)).map_err(|value| {
1144 if value.is::<rustc_errors::FatalErrorMarker>() {
1147 panic::resume_unwind(value);
1152 /// Variant of `catch_fatal_errors` for the `interface::Result` return type
1153 /// that also computes the exit code.
1154 pub fn catch_with_exit_code(f: impl FnOnce() -> interface::Result<()>) -> i32 {
1155 let result = catch_fatal_errors(f).and_then(|result| result);
1157 Ok(()) => EXIT_SUCCESS,
1158 Err(_) => EXIT_FAILURE,
1162 static DEFAULT_HOOK: SyncLazy<Box<dyn Fn(&panic::PanicInfo<'_>) + Sync + Send + 'static>> =
1164 let hook = panic::take_hook();
1165 panic::set_hook(Box::new(|info| {
1166 // Invoke the default handler, which prints the actual panic message and optionally a backtrace
1167 (*DEFAULT_HOOK)(info);
1169 // Separate the output with an empty line
1172 // Print the ICE message
1173 report_ice(info, BUG_REPORT_URL);
1178 /// Prints the ICE message, including query stack, but without backtrace.
1180 /// The message will point the user at `bug_report_url` to report the ICE.
1182 /// When `install_ice_hook` is called, this function will be called as the panic
1184 pub fn report_ice(info: &panic::PanicInfo<'_>, bug_report_url: &str) {
1185 let emitter = Box::new(rustc_errors::emitter::EmitterWriter::stderr(
1186 rustc_errors::ColorConfig::Auto,
1193 let handler = rustc_errors::Handler::with_emitter(true, None, emitter);
1195 // a .span_bug or .bug call has already printed what
1196 // it wants to print.
1197 if !info.payload().is::<rustc_errors::ExplicitBug>() {
1198 let d = rustc_errors::Diagnostic::new(rustc_errors::Level::Bug, "unexpected panic");
1199 handler.emit_diagnostic(&d);
1202 let mut xs: Vec<Cow<'static, str>> = vec![
1203 "the compiler unexpectedly panicked. this is a bug.".into(),
1204 format!("we would appreciate a bug report: {}", bug_report_url).into(),
1206 "rustc {} running on {}",
1207 util::version_str().unwrap_or("unknown_version"),
1208 config::host_triple()
1213 if let Some((flags, excluded_cargo_defaults)) = extra_compiler_flags() {
1214 xs.push(format!("compiler flags: {}", flags.join(" ")).into());
1216 if excluded_cargo_defaults {
1217 xs.push("some of the compiler flags provided by cargo are hidden".into());
1222 handler.note_without_error(note);
1225 // If backtraces are enabled, also print the query stack
1226 let backtrace = env::var_os("RUST_BACKTRACE").map_or(false, |x| &x != "0");
1228 let num_frames = if backtrace { None } else { Some(2) };
1230 interface::try_print_query_stack(&handler, num_frames);
1234 if env::var("RUSTC_BREAK_ON_ICE").is_ok() {
1235 // Trigger a debugger if we crashed during bootstrap
1236 winapi::um::debugapi::DebugBreak();
1241 /// Installs a panic hook that will print the ICE message on unexpected panics.
1243 /// A custom rustc driver can skip calling this to set up a custom ICE hook.
1244 pub fn install_ice_hook() {
1245 // If the user has not explicitly overriden "RUST_BACKTRACE", then produce
1246 // full backtraces. When a compiler ICE happens, we want to gather
1247 // as much information as possible to present in the issue opened
1248 // by the user. Compiler developers and other rustc users can
1249 // opt in to less-verbose backtraces by manually setting "RUST_BACKTRACE"
1250 // (e.g. `RUST_BACKTRACE=1`)
1251 if std::env::var("RUST_BACKTRACE").is_err() {
1252 std::env::set_var("RUST_BACKTRACE", "full");
1254 SyncLazy::force(&DEFAULT_HOOK);
1257 /// This allows tools to enable rust logging without having to magically match rustc's
1258 /// tracing crate version.
1259 pub fn init_rustc_env_logger() {
1260 if let Err(error) = rustc_log::init_rustc_env_logger() {
1261 early_error(ErrorOutputType::default(), &error.to_string());
1265 /// This allows tools to enable rust logging without having to magically match rustc's
1266 /// tracing crate version. In contrast to `init_rustc_env_logger` it allows you to choose an env var
1267 /// other than `RUSTC_LOG`.
1268 pub fn init_env_logger(env: &str) {
1269 if let Err(error) = rustc_log::init_env_logger(env) {
1270 early_error(ErrorOutputType::default(), &error.to_string());
1274 #[cfg(all(unix, any(target_env = "gnu", target_os = "macos")))]
1275 mod signal_handler {
1277 fn backtrace_symbols_fd(
1278 buffer: *const *mut libc::c_void,
1284 extern "C" fn print_stack_trace(_: libc::c_int) {
1285 const MAX_FRAMES: usize = 256;
1286 static mut STACK_TRACE: [*mut libc::c_void; MAX_FRAMES] =
1287 [std::ptr::null_mut(); MAX_FRAMES];
1289 let depth = libc::backtrace(STACK_TRACE.as_mut_ptr(), MAX_FRAMES as i32);
1293 backtrace_symbols_fd(STACK_TRACE.as_ptr(), depth, 2);
1297 // When an error signal (such as SIGABRT or SIGSEGV) is delivered to the
1298 // process, print a stack trace and then exit.
1299 pub(super) fn install() {
1301 const ALT_STACK_SIZE: usize = libc::MINSIGSTKSZ + 64 * 1024;
1302 let mut alt_stack: libc::stack_t = std::mem::zeroed();
1304 std::alloc::alloc(std::alloc::Layout::from_size_align(ALT_STACK_SIZE, 1).unwrap())
1305 as *mut libc::c_void;
1306 alt_stack.ss_size = ALT_STACK_SIZE;
1307 libc::sigaltstack(&alt_stack, std::ptr::null_mut());
1309 let mut sa: libc::sigaction = std::mem::zeroed();
1310 sa.sa_sigaction = print_stack_trace as libc::sighandler_t;
1311 sa.sa_flags = libc::SA_NODEFER | libc::SA_RESETHAND | libc::SA_ONSTACK;
1312 libc::sigemptyset(&mut sa.sa_mask);
1313 libc::sigaction(libc::SIGSEGV, &sa, std::ptr::null_mut());
1318 #[cfg(not(all(unix, any(target_env = "gnu", target_os = "macos"))))]
1319 mod signal_handler {
1320 pub(super) fn install() {}
1323 pub fn main() -> ! {
1324 let start_time = Instant::now();
1325 let start_rss = get_resident_set_size();
1326 init_rustc_env_logger();
1327 signal_handler::install();
1328 let mut callbacks = TimePassesCallbacks::default();
1330 let exit_code = catch_with_exit_code(|| {
1331 let args = env::args_os()
1334 arg.into_string().unwrap_or_else(|arg| {
1336 ErrorOutputType::default(),
1337 &format!("argument {} is not valid Unicode: {:?}", i, arg),
1341 .collect::<Vec<_>>();
1342 RunCompiler::new(&args, &mut callbacks).run()
1345 if callbacks.time_passes {
1346 let end_rss = get_resident_set_size();
1347 print_time_passes_entry("total", start_time.elapsed(), start_rss, end_rss);
1350 process::exit(exit_code)