5 //! This API is completely unstable and subject to change.
7 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
10 #![feature(once_cell)]
11 #![recursion_limit = "256"]
12 #![allow(rustc::potential_query_instability)]
17 pub extern crate rustc_plugin_impl as plugin;
20 use rustc_codegen_ssa::{traits::CodegenBackend, CodegenResults};
21 use rustc_data_structures::profiling::{get_resident_set_size, print_time_passes_entry};
22 use rustc_data_structures::sync::SeqCst;
23 use rustc_errors::registry::{InvalidErrorCode, Registry};
24 use rustc_errors::{ErrorReported, PResult};
25 use rustc_feature::find_gated_cfg;
26 use rustc_interface::util::{self, collect_crate_types, get_codegen_backend};
27 use rustc_interface::{interface, Queries};
28 use rustc_lint::LintStore;
29 use rustc_log::stdout_isatty;
30 use rustc_metadata::locator;
31 use rustc_save_analysis as save;
32 use rustc_save_analysis::DumpHandler;
33 use rustc_serialize::json::ToJson;
34 use rustc_session::config::{nightly_options, CG_OPTIONS, DB_OPTIONS};
35 use rustc_session::config::{ErrorOutputType, Input, OutputType, PrintRequest, TrimmedDefPaths};
36 use rustc_session::cstore::MetadataLoader;
37 use rustc_session::getopts;
38 use rustc_session::lint::{Lint, LintId};
39 use rustc_session::{config, DiagnosticOutput, Session};
40 use rustc_session::{early_error, early_error_no_abort, early_warn};
41 use rustc_span::source_map::{FileLoader, FileName};
42 use rustc_span::symbol::sym;
46 use std::default::Default;
48 use std::ffi::OsString;
50 use std::io::{self, Read, Write};
51 use std::lazy::SyncLazy;
52 use std::panic::{self, catch_unwind};
53 use std::path::PathBuf;
54 use std::process::{self, Command, Stdio};
56 use std::time::Instant;
61 /// Exit status code used for successful compilation and help output.
62 pub const EXIT_SUCCESS: i32 = 0;
64 /// Exit status code used for compilation failures and invalid flags.
65 pub const EXIT_FAILURE: i32 = 1;
67 const BUG_REPORT_URL: &str = "https://github.com/rust-lang/rust/issues/new\
68 ?labels=C-bug%2C+I-ICE%2C+T-compiler&template=ice.md";
70 const ICE_REPORT_COMPILER_FLAGS: &[&str] = &["-Z", "-C", "--crate-type"];
72 const ICE_REPORT_COMPILER_FLAGS_EXCLUDE: &[&str] = &["metadata", "extra-filename"];
74 const ICE_REPORT_COMPILER_FLAGS_STRIP_VALUE: &[&str] = &["incremental"];
76 pub fn abort_on_err<T>(result: Result<T, ErrorReported>, sess: &Session) -> T {
79 sess.abort_if_errors();
80 panic!("error reported but abort_if_errors didn't abort???");
87 /// Called before creating the compiler instance
88 fn config(&mut self, _config: &mut interface::Config) {}
89 /// Called after parsing. Return value instructs the compiler whether to
90 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
91 fn after_parsing<'tcx>(
93 _compiler: &interface::Compiler,
94 _queries: &'tcx Queries<'tcx>,
98 /// Called after expansion. Return value instructs the compiler whether to
99 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
100 fn after_expansion<'tcx>(
102 _compiler: &interface::Compiler,
103 _queries: &'tcx Queries<'tcx>,
105 Compilation::Continue
107 /// Called after analysis. Return value instructs the compiler whether to
108 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
109 fn after_analysis<'tcx>(
111 _compiler: &interface::Compiler,
112 _queries: &'tcx Queries<'tcx>,
114 Compilation::Continue
119 pub struct TimePassesCallbacks {
123 impl Callbacks for TimePassesCallbacks {
124 fn config(&mut self, config: &mut interface::Config) {
125 // If a --prints=... option has been given, we don't print the "total"
126 // time because it will mess up the --prints output. See #64339.
127 self.time_passes = config.opts.prints.is_empty()
128 && (config.opts.debugging_opts.time_passes || config.opts.debugging_opts.time);
129 config.opts.trimmed_def_paths = TrimmedDefPaths::GoodPath;
133 pub fn diagnostics_registry() -> Registry {
134 Registry::new(rustc_error_codes::DIAGNOSTICS)
137 /// This is the primary entry point for rustc.
138 pub struct RunCompiler<'a, 'b> {
139 at_args: &'a [String],
140 callbacks: &'b mut (dyn Callbacks + Send),
141 file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
142 emitter: Option<Box<dyn Write + Send>>,
143 make_codegen_backend:
144 Option<Box<dyn FnOnce(&config::Options) -> Box<dyn CodegenBackend> + Send>>,
147 impl<'a, 'b> RunCompiler<'a, 'b> {
148 pub fn new(at_args: &'a [String], callbacks: &'b mut (dyn Callbacks + Send)) -> Self {
149 Self { at_args, callbacks, file_loader: None, emitter: None, make_codegen_backend: None }
152 /// Set a custom codegen backend.
155 pub fn set_make_codegen_backend(
157 make_codegen_backend: Option<
158 Box<dyn FnOnce(&config::Options) -> Box<dyn CodegenBackend> + Send>,
161 self.make_codegen_backend = make_codegen_backend;
165 /// Emit diagnostics to the specified location.
168 pub fn set_emitter(&mut self, emitter: Option<Box<dyn Write + Send>>) -> &mut Self {
169 self.emitter = emitter;
173 /// Load files from sources other than the file system.
176 pub fn set_file_loader(
178 file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
180 self.file_loader = file_loader;
184 /// Parse args and run the compiler.
185 pub fn run(self) -> interface::Result<()> {
191 self.make_codegen_backend,
197 callbacks: &mut (dyn Callbacks + Send),
198 file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
199 emitter: Option<Box<dyn Write + Send>>,
200 make_codegen_backend: Option<
201 Box<dyn FnOnce(&config::Options) -> Box<dyn CodegenBackend> + Send>,
203 ) -> interface::Result<()> {
204 let args = args::arg_expand_all(at_args);
206 let diagnostic_output = emitter.map_or(DiagnosticOutput::Default, DiagnosticOutput::Raw);
207 let Some(matches) = handle_options(&args) else { return Ok(()) };
209 let sopts = config::build_session_options(&matches);
211 if let Some(ref code) = matches.opt_str("explain") {
212 handle_explain(diagnostics_registry(), code, sopts.error_format);
216 let cfg = interface::parse_cfgspecs(matches.opt_strs("cfg"));
217 let check_cfg = interface::parse_check_cfg(matches.opt_strs("check-cfg"));
218 let (odir, ofile) = make_output(&matches);
219 let mut config = interface::Config {
222 crate_check_cfg: check_cfg,
223 input: Input::File(PathBuf::new()),
229 lint_caps: Default::default(),
230 parse_sess_created: None,
231 register_lints: None,
232 override_queries: None,
233 make_codegen_backend,
234 registry: diagnostics_registry(),
237 match make_input(config.opts.error_format, &matches.free) {
238 Err(ErrorReported) => return Err(ErrorReported),
239 Ok(Some((input, input_file_path))) => {
240 config.input = input;
241 config.input_path = input_file_path;
243 callbacks.config(&mut config);
245 Ok(None) => match matches.free.len() {
247 callbacks.config(&mut config);
248 interface::run_compiler(config, |compiler| {
249 let sopts = &compiler.session().opts;
250 if sopts.describe_lints {
251 let mut lint_store = rustc_lint::new_lint_store(
252 sopts.debugging_opts.no_interleave_lints,
253 compiler.session().unstable_options(),
255 let registered_lints =
256 if let Some(register_lints) = compiler.register_lints() {
257 register_lints(compiler.session(), &mut lint_store);
262 describe_lints(compiler.session(), &lint_store, registered_lints);
265 let should_stop = print_crate_info(
266 &***compiler.codegen_backend(),
269 compiler.output_dir(),
270 compiler.output_file(),
271 compiler.temps_dir(),
274 if should_stop == Compilation::Stop {
277 early_error(sopts.error_format, "no input filename given")
281 1 => panic!("make_input should have provided valid inputs"),
283 config.opts.error_format,
285 "multiple input filenames provided (first two filenames are `{}` and `{}`)",
286 matches.free[0], matches.free[1],
292 interface::run_compiler(config, |compiler| {
293 let sess = compiler.session();
294 let should_stop = print_crate_info(
295 &***compiler.codegen_backend(),
297 Some(compiler.input()),
298 compiler.output_dir(),
299 compiler.output_file(),
300 compiler.temps_dir(),
303 list_metadata(sess, &*compiler.codegen_backend().metadata_loader(), compiler.input())
305 .and_then(|| try_process_rlink(sess, compiler));
307 if should_stop == Compilation::Stop {
308 return sess.compile_status();
311 let linker = compiler.enter(|queries| {
312 let early_exit = || sess.compile_status().map(|_| None);
315 if let Some(ppm) = &sess.opts.pretty {
316 if ppm.needs_ast_map() {
317 let expanded_crate = queries.expansion()?.peek().0.clone();
318 queries.global_ctxt()?.peek_mut().enter(|tcx| {
319 pretty::print_after_hir_lowering(
324 compiler.output_file().as_ref().map(|p| &**p),
329 let krate = queries.parse()?.take();
330 pretty::print_after_parsing(
335 compiler.output_file().as_ref().map(|p| &**p),
338 trace!("finished pretty-printing");
342 if callbacks.after_parsing(compiler, queries) == Compilation::Stop {
346 if sess.opts.debugging_opts.parse_only
347 || sess.opts.debugging_opts.show_span.is_some()
348 || sess.opts.debugging_opts.ast_json_noexpand
354 let (_, lint_store) = &*queries.register_plugins()?.peek();
356 // Lint plugins are registered; now we can process command line flags.
357 if sess.opts.describe_lints {
358 describe_lints(sess, lint_store, true);
363 queries.expansion()?;
364 if callbacks.after_expansion(compiler, queries) == Compilation::Stop {
368 queries.prepare_outputs()?;
370 if sess.opts.output_types.contains_key(&OutputType::DepInfo)
371 && sess.opts.output_types.len() == 1
376 queries.global_ctxt()?;
378 if sess.opts.debugging_opts.no_analysis || sess.opts.debugging_opts.ast_json {
382 queries.global_ctxt()?.peek_mut().enter(|tcx| {
383 let result = tcx.analysis(());
384 if sess.opts.debugging_opts.save_analysis {
385 let crate_name = queries.crate_name()?.peek().clone();
386 sess.time("save_analysis", || {
393 compiler.output_dir().as_ref().map(|p| &**p),
402 if callbacks.after_analysis(compiler, queries) == Compilation::Stop {
406 queries.ongoing_codegen()?;
408 if sess.opts.debugging_opts.print_type_sizes {
409 sess.code_stats.print_type_sizes();
412 let linker = queries.linker()?;
416 if let Some(linker) = linker {
417 let _timer = sess.timer("link");
421 if sess.opts.debugging_opts.perf_stats {
422 sess.print_perf_stats();
425 if sess.opts.debugging_opts.print_fuel.is_some() {
427 "Fuel used by {}: {}",
428 sess.opts.debugging_opts.print_fuel.as_ref().unwrap(),
429 sess.print_fuel.load(SeqCst)
438 pub fn set_sigpipe_handler() {
440 // Set the SIGPIPE signal handler, so that an EPIPE
441 // will cause rustc to terminate, as expected.
442 assert_ne!(libc::signal(libc::SIGPIPE, libc::SIG_DFL), libc::SIG_ERR);
447 pub fn set_sigpipe_handler() {}
449 // Extract output directory and file from matches.
450 fn make_output(matches: &getopts::Matches) -> (Option<PathBuf>, Option<PathBuf>) {
451 let odir = matches.opt_str("out-dir").map(|o| PathBuf::from(&o));
452 let ofile = matches.opt_str("o").map(|o| PathBuf::from(&o));
456 // Extract input (string or file and optional path) from matches.
458 error_format: ErrorOutputType,
459 free_matches: &[String],
460 ) -> Result<Option<(Input, Option<PathBuf>)>, ErrorReported> {
461 if free_matches.len() == 1 {
462 let ifile = &free_matches[0];
464 let mut src = String::new();
465 if io::stdin().read_to_string(&mut src).is_err() {
466 // Immediately stop compilation if there was an issue reading
467 // the input (for example if the input stream is not UTF-8).
468 early_error_no_abort(
470 "couldn't read from stdin, as it did not contain valid UTF-8",
472 return Err(ErrorReported);
474 if let Ok(path) = env::var("UNSTABLE_RUSTDOC_TEST_PATH") {
475 let line = env::var("UNSTABLE_RUSTDOC_TEST_LINE").expect(
476 "when UNSTABLE_RUSTDOC_TEST_PATH is set \
477 UNSTABLE_RUSTDOC_TEST_LINE also needs to be set",
479 let line = isize::from_str_radix(&line, 10)
480 .expect("UNSTABLE_RUSTDOC_TEST_LINE needs to be an number");
481 let file_name = FileName::doc_test_source_code(PathBuf::from(path), line);
482 Ok(Some((Input::Str { name: file_name, input: src }, None)))
484 Ok(Some((Input::Str { name: FileName::anon_source_code(&src), input: src }, None)))
487 Ok(Some((Input::File(PathBuf::from(ifile)), Some(PathBuf::from(ifile)))))
494 /// Whether to stop or continue compilation.
495 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
496 pub enum Compilation {
502 pub fn and_then<F: FnOnce() -> Compilation>(self, next: F) -> Compilation {
504 Compilation::Stop => Compilation::Stop,
505 Compilation::Continue => next(),
510 fn handle_explain(registry: Registry, code: &str, output: ErrorOutputType) {
511 let upper_cased_code = code.to_ascii_uppercase();
512 let normalised = if upper_cased_code.starts_with('E') {
515 format!("E{0:0>4}", code)
517 match registry.try_find_description(&normalised) {
518 Ok(Some(description)) => {
519 let mut is_in_code_block = false;
520 let mut text = String::new();
521 // Slice off the leading newline and print.
522 for line in description.lines() {
524 line.find(|c: char| !c.is_whitespace()).unwrap_or_else(|| line.len());
525 let dedented_line = &line[indent_level..];
526 if dedented_line.starts_with("```") {
527 is_in_code_block = !is_in_code_block;
528 text.push_str(&line[..(indent_level + 3)]);
529 } else if is_in_code_block && dedented_line.starts_with("# ") {
537 show_content_with_pager(&text);
543 early_error(output, &format!("no extended information for {}", code));
545 Err(InvalidErrorCode) => {
546 early_error(output, &format!("{} is not a valid error code", code));
551 fn show_content_with_pager(content: &str) {
552 let pager_name = env::var_os("PAGER").unwrap_or_else(|| {
553 if cfg!(windows) { OsString::from("more.com") } else { OsString::from("less") }
556 let mut fallback_to_println = false;
558 match Command::new(pager_name).stdin(Stdio::piped()).spawn() {
560 if let Some(pipe) = pager.stdin.as_mut() {
561 if pipe.write_all(content.as_bytes()).is_err() {
562 fallback_to_println = true;
566 if pager.wait().is_err() {
567 fallback_to_println = true;
571 fallback_to_println = true;
575 // If pager fails for whatever reason, we should still print the content
576 // to standard output
577 if fallback_to_println {
578 print!("{}", content);
582 pub fn try_process_rlink(sess: &Session, compiler: &interface::Compiler) -> Compilation {
583 if sess.opts.debugging_opts.link_only {
584 if let Input::File(file) = compiler.input() {
585 // FIXME: #![crate_type] and #![crate_name] support not implemented yet
586 sess.init_crate_types(collect_crate_types(sess, &[]));
587 let outputs = compiler.build_output_filenames(sess, &[]);
588 let rlink_data = fs::read(file).unwrap_or_else(|err| {
589 sess.fatal(&format!("failed to read rlink file: {}", err));
591 let mut decoder = rustc_serialize::opaque::Decoder::new(&rlink_data, 0);
592 let codegen_results: CodegenResults = rustc_serialize::Decodable::decode(&mut decoder);
593 let result = compiler.codegen_backend().link(sess, codegen_results, &outputs);
594 abort_on_err(result, sess);
596 sess.fatal("rlink must be a file")
600 Compilation::Continue
604 pub fn list_metadata(
606 metadata_loader: &dyn MetadataLoader,
609 if sess.opts.debugging_opts.ls {
611 Input::File(ref ifile) => {
612 let path = &(*ifile);
613 let mut v = Vec::new();
614 locator::list_file_metadata(&sess.target, path, metadata_loader, &mut v).unwrap();
615 println!("{}", String::from_utf8(v).unwrap());
617 Input::Str { .. } => {
618 early_error(ErrorOutputType::default(), "cannot list metadata for stdin");
621 return Compilation::Stop;
624 Compilation::Continue
628 codegen_backend: &dyn CodegenBackend,
630 input: Option<&Input>,
631 odir: &Option<PathBuf>,
632 ofile: &Option<PathBuf>,
633 temps_dir: &Option<PathBuf>,
635 use rustc_session::config::PrintRequest::*;
636 // NativeStaticLibs and LinkArgs are special - printed during linking
637 // (empty iterator returns true)
638 if sess.opts.prints.iter().all(|&p| p == NativeStaticLibs || p == LinkArgs) {
639 return Compilation::Continue;
642 let attrs = match input {
645 let result = parse_crate_attrs(sess, input);
647 Ok(attrs) => Some(attrs),
648 Err(mut parse_error) => {
650 return Compilation::Stop;
655 for req in &sess.opts.prints {
658 let mut targets = rustc_target::spec::TARGETS.iter().copied().collect::<Vec<_>>();
659 targets.sort_unstable();
660 println!("{}", targets.join("\n"));
662 Sysroot => println!("{}", sess.sysroot.display()),
663 TargetLibdir => println!("{}", sess.target_tlib_path.dir.display()),
664 TargetSpec => println!("{}", sess.target.to_json().pretty()),
665 FileNames | CrateName => {
666 let input = input.unwrap_or_else(|| {
667 early_error(ErrorOutputType::default(), "no input file provided")
669 let attrs = attrs.as_ref().unwrap();
670 let t_outputs = rustc_interface::util::build_output_filenames(
671 input, odir, ofile, temps_dir, attrs, sess,
673 let id = rustc_session::output::find_crate_name(sess, attrs, input);
674 if *req == PrintRequest::CrateName {
678 let crate_types = collect_crate_types(sess, attrs);
679 for &style in &crate_types {
681 rustc_session::output::filename_for_input(sess, style, &id, &t_outputs);
682 println!("{}", fname.file_name().unwrap().to_string_lossy());
690 .filter_map(|&(name, value)| {
691 // Note that crt-static is a specially recognized cfg
692 // directive that's printed out here as part of
693 // rust-lang/rust#37406, but in general the
694 // `target_feature` cfg is gated under
695 // rust-lang/rust#29717. For now this is just
696 // specifically allowing the crt-static cfg and that's
697 // it, this is intended to get into Cargo and then go
698 // through to build scripts.
699 if (name != sym::target_feature || value != Some(sym::crt_dash_static))
700 && !sess.is_nightly_build()
701 && find_gated_cfg(|cfg_sym| cfg_sym == name).is_some()
706 if let Some(value) = value {
707 Some(format!("{}=\"{}\"", name, value))
709 Some(name.to_string())
712 .collect::<Vec<String>>();
723 | StackProtectorStrategies
724 | TargetFeatures => {
725 codegen_backend.print(*req, sess);
727 // Any output here interferes with Cargo's parsing of other printed output
728 NativeStaticLibs => {}
735 /// Prints version information
736 pub fn version(binary: &str, matches: &getopts::Matches) {
737 let verbose = matches.opt_present("verbose");
739 println!("{} {}", binary, util::version_str().unwrap_or("unknown version"));
742 fn unw(x: Option<&str>) -> &str {
743 x.unwrap_or("unknown")
745 println!("binary: {}", binary);
746 println!("commit-hash: {}", unw(util::commit_hash_str()));
747 println!("commit-date: {}", unw(util::commit_date_str()));
748 println!("host: {}", config::host_triple());
749 println!("release: {}", unw(util::release_str()));
751 let debug_flags = matches.opt_strs("Z");
752 let backend_name = debug_flags.iter().find_map(|x| x.strip_prefix("codegen-backend="));
753 get_codegen_backend(&None, backend_name).print_version();
757 fn usage(verbose: bool, include_unstable_options: bool, nightly_build: bool) {
758 let groups = if verbose { config::rustc_optgroups() } else { config::rustc_short_optgroups() };
759 let mut options = getopts::Options::new();
760 for option in groups.iter().filter(|x| include_unstable_options || x.is_stable()) {
761 (option.apply)(&mut options);
763 let message = "Usage: rustc [OPTIONS] INPUT";
764 let nightly_help = if nightly_build {
765 "\n -Z help Print unstable compiler options"
769 let verbose_help = if verbose {
772 "\n --help -v Print the full set of options rustc accepts"
774 let at_path = if verbose {
775 " @path Read newline separated options from `path`\n"
780 "{options}{at_path}\nAdditional help:
781 -C help Print codegen options
783 Print 'lint' options and default settings{nightly}{verbose}\n",
784 options = options.usage(message),
786 nightly = nightly_help,
787 verbose = verbose_help
791 fn print_wall_help() {
794 The flag `-Wall` does not exist in `rustc`. Most useful lints are enabled by
795 default. Use `rustc -W help` to see all available lints. It's more common to put
796 warning settings in the crate root using `#![warn(LINT_NAME)]` instead of using
797 the command line flag directly.
802 /// Write to stdout lint command options, together with a list of all available lints
803 pub fn describe_lints(sess: &Session, lint_store: &LintStore, loaded_plugins: bool) {
806 Available lint options:
807 -W <foo> Warn about <foo>
811 -F <foo> Forbid <foo> \
812 (deny <foo> and all attempts to override)
817 fn sort_lints(sess: &Session, mut lints: Vec<&'static Lint>) -> Vec<&'static Lint> {
818 // The sort doesn't case-fold but it's doubtful we care.
819 lints.sort_by_cached_key(|x: &&Lint| (x.default_level(sess.edition()), x.name));
824 lints: Vec<(&'static str, Vec<LintId>, bool)>,
825 ) -> Vec<(&'static str, Vec<LintId>)> {
826 let mut lints: Vec<_> = lints.into_iter().map(|(x, y, _)| (x, y)).collect();
827 lints.sort_by_key(|l| l.0);
831 let (plugin, builtin): (Vec<_>, _) =
832 lint_store.get_lints().iter().cloned().partition(|&lint| lint.is_plugin);
833 let plugin = sort_lints(sess, plugin);
834 let builtin = sort_lints(sess, builtin);
836 let (plugin_groups, builtin_groups): (Vec<_>, _) =
837 lint_store.get_lint_groups().partition(|&(.., p)| p);
838 let plugin_groups = sort_lint_groups(plugin_groups);
839 let builtin_groups = sort_lint_groups(builtin_groups);
842 plugin.iter().chain(&builtin).map(|&s| s.name.chars().count()).max().unwrap_or(0);
843 let padded = |x: &str| {
844 let mut s = " ".repeat(max_name_len - x.chars().count());
849 println!("Lint checks provided by rustc:\n");
850 println!(" {} {:7.7} {}", padded("name"), "default", "meaning");
851 println!(" {} {:7.7} {}", padded("----"), "-------", "-------");
853 let print_lints = |lints: Vec<&Lint>| {
855 let name = lint.name_lower().replace('_', "-");
859 lint.default_level(sess.edition()).as_str(),
866 print_lints(builtin);
868 let max_name_len = max(
872 .chain(&builtin_groups)
873 .map(|&(s, _)| s.chars().count())
878 let padded = |x: &str| {
879 let mut s = " ".repeat(max_name_len - x.chars().count());
884 println!("Lint groups provided by rustc:\n");
885 println!(" {} sub-lints", padded("name"));
886 println!(" {} ---------", padded("----"));
887 println!(" {} all lints that are set to issue warnings", padded("warnings"));
889 let print_lint_groups = |lints: Vec<(&'static str, Vec<LintId>)>| {
890 for (name, to) in lints {
891 let name = name.to_lowercase().replace('_', "-");
894 .map(|x| x.to_string().replace('_', "-"))
895 .collect::<Vec<String>>()
897 println!(" {} {}", padded(&name), desc);
902 print_lint_groups(builtin_groups);
904 match (loaded_plugins, plugin.len(), plugin_groups.len()) {
905 (false, 0, _) | (false, _, 0) => {
906 println!("Lint tools like Clippy can provide additional lints and lint groups.");
908 (false, ..) => panic!("didn't load lint plugins but got them anyway!"),
909 (true, 0, 0) => println!("This crate does not load any lint plugins or lint groups."),
912 println!("Lint checks provided by plugins loaded by this crate:\n");
916 println!("Lint groups provided by plugins loaded by this crate:\n");
917 print_lint_groups(plugin_groups);
923 fn describe_debug_flags() {
924 println!("\nAvailable options:\n");
925 print_flag_list("-Z", config::DB_OPTIONS);
928 fn describe_codegen_flags() {
929 println!("\nAvailable codegen options:\n");
930 print_flag_list("-C", config::CG_OPTIONS);
933 fn print_flag_list<T>(
935 flag_list: &[(&'static str, T, &'static str, &'static str)],
937 let max_len = flag_list.iter().map(|&(name, _, _, _)| name.chars().count()).max().unwrap_or(0);
939 for &(name, _, _, desc) in flag_list {
941 " {} {:>width$}=val -- {}",
943 name.replace('_', "-"),
950 /// Process command line options. Emits messages as appropriate. If compilation
951 /// should continue, returns a getopts::Matches object parsed from args,
952 /// otherwise returns `None`.
954 /// The compiler's handling of options is a little complicated as it ties into
955 /// our stability story. The current intention of each compiler option is to
956 /// have one of two modes:
958 /// 1. An option is stable and can be used everywhere.
959 /// 2. An option is unstable, and can only be used on nightly.
961 /// Like unstable library and language features, however, unstable options have
962 /// always required a form of "opt in" to indicate that you're using them. This
963 /// provides the easy ability to scan a code base to check to see if anything
964 /// unstable is being used. Currently, this "opt in" is the `-Z` "zed" flag.
966 /// All options behind `-Z` are considered unstable by default. Other top-level
967 /// options can also be considered unstable, and they were unlocked through the
968 /// `-Z unstable-options` flag. Note that `-Z` remains to be the root of
969 /// instability in both cases, though.
971 /// So with all that in mind, the comments below have some more detail about the
972 /// contortions done here to get things to work out correctly.
973 pub fn handle_options(args: &[String]) -> Option<getopts::Matches> {
974 // Throw away the first argument, the name of the binary
975 let args = &args[1..];
978 // user did not write `-v` nor `-Z unstable-options`, so do not
979 // include that extra information.
981 rustc_feature::UnstableFeatures::from_environment(None).is_nightly_build();
982 usage(false, false, nightly_build);
986 // Parse with *all* options defined in the compiler, we don't worry about
987 // option stability here we just want to parse as much as possible.
988 let mut options = getopts::Options::new();
989 for option in config::rustc_optgroups() {
990 (option.apply)(&mut options);
992 let matches = options.parse(args).unwrap_or_else(|e| {
994 getopts::Fail::UnrecognizedOption(ref opt) => CG_OPTIONS
996 .map(|&(name, ..)| ('C', name))
997 .chain(DB_OPTIONS.iter().map(|&(name, ..)| ('Z', name)))
998 .find(|&(_, name)| *opt == name.replace('_', "-"))
999 .map(|(flag, _)| format!("{}. Did you mean `-{} {}`?", e, flag, opt)),
1002 early_error(ErrorOutputType::default(), &msg.unwrap_or_else(|| e.to_string()));
1005 // For all options we just parsed, we check a few aspects:
1007 // * If the option is stable, we're all good
1008 // * If the option wasn't passed, we're all good
1009 // * If `-Z unstable-options` wasn't passed (and we're not a -Z option
1010 // ourselves), then we require the `-Z unstable-options` flag to unlock
1011 // this option that was passed.
1012 // * If we're a nightly compiler, then unstable options are now unlocked, so
1013 // we're good to go.
1014 // * Otherwise, if we're an unstable option then we generate an error
1015 // (unstable option being used on stable)
1016 nightly_options::check_nightly_options(&matches, &config::rustc_optgroups());
1018 if matches.opt_present("h") || matches.opt_present("help") {
1019 // Only show unstable options in --help if we accept unstable options.
1020 let unstable_enabled = nightly_options::is_unstable_enabled(&matches);
1021 let nightly_build = nightly_options::match_is_nightly_build(&matches);
1022 usage(matches.opt_present("verbose"), unstable_enabled, nightly_build);
1026 // Handle the special case of -Wall.
1027 let wall = matches.opt_strs("W");
1028 if wall.iter().any(|x| *x == "all") {
1030 rustc_errors::FatalError.raise();
1033 // Don't handle -W help here, because we might first load plugins.
1034 let debug_flags = matches.opt_strs("Z");
1035 if debug_flags.iter().any(|x| *x == "help") {
1036 describe_debug_flags();
1040 let cg_flags = matches.opt_strs("C");
1042 if cg_flags.iter().any(|x| *x == "help") {
1043 describe_codegen_flags();
1047 if cg_flags.iter().any(|x| *x == "no-stack-check") {
1049 ErrorOutputType::default(),
1050 "the --no-stack-check flag is deprecated and does nothing",
1054 if cg_flags.iter().any(|x| *x == "passes=list") {
1055 let backend_name = debug_flags.iter().find_map(|x| {
1056 if x.starts_with("codegen-backend=") {
1057 Some(&x["codegen-backends=".len()..])
1062 get_codegen_backend(&None, backend_name).print_passes();
1066 if matches.opt_present("version") {
1067 version("rustc", &matches);
1074 fn parse_crate_attrs<'a>(sess: &'a Session, input: &Input) -> PResult<'a, Vec<ast::Attribute>> {
1076 Input::File(ifile) => rustc_parse::parse_crate_attrs_from_file(ifile, &sess.parse_sess),
1077 Input::Str { name, input } => rustc_parse::parse_crate_attrs_from_source_str(
1085 /// Gets a list of extra command-line flags provided by the user, as strings.
1087 /// This function is used during ICEs to show more information useful for
1088 /// debugging, since some ICEs only happens with non-default compiler flags
1089 /// (and the users don't always report them).
1090 fn extra_compiler_flags() -> Option<(Vec<String>, bool)> {
1091 let mut args = env::args_os().map(|arg| arg.to_string_lossy().to_string()).peekable();
1093 let mut result = Vec::new();
1094 let mut excluded_cargo_defaults = false;
1095 while let Some(arg) = args.next() {
1096 if let Some(a) = ICE_REPORT_COMPILER_FLAGS.iter().find(|a| arg.starts_with(*a)) {
1097 let content = if arg.len() == a.len() {
1099 Some(arg) => arg.to_string(),
1102 } else if arg.get(a.len()..a.len() + 1) == Some("=") {
1103 arg[a.len() + 1..].to_string()
1105 arg[a.len()..].to_string()
1107 if ICE_REPORT_COMPILER_FLAGS_EXCLUDE.iter().any(|exc| content.starts_with(exc)) {
1108 excluded_cargo_defaults = true;
1110 result.push(a.to_string());
1111 match ICE_REPORT_COMPILER_FLAGS_STRIP_VALUE.iter().find(|s| content.starts_with(*s))
1113 Some(s) => result.push(s.to_string()),
1114 None => result.push(content),
1120 if !result.is_empty() { Some((result, excluded_cargo_defaults)) } else { None }
1123 /// Runs a closure and catches unwinds triggered by fatal errors.
1125 /// The compiler currently unwinds with a special sentinel value to abort
1126 /// compilation on fatal errors. This function catches that sentinel and turns
1127 /// the panic into a `Result` instead.
1128 pub fn catch_fatal_errors<F: FnOnce() -> R, R>(f: F) -> Result<R, ErrorReported> {
1129 catch_unwind(panic::AssertUnwindSafe(f)).map_err(|value| {
1130 if value.is::<rustc_errors::FatalErrorMarker>() {
1133 panic::resume_unwind(value);
1138 /// Variant of `catch_fatal_errors` for the `interface::Result` return type
1139 /// that also computes the exit code.
1140 pub fn catch_with_exit_code(f: impl FnOnce() -> interface::Result<()>) -> i32 {
1141 let result = catch_fatal_errors(f).and_then(|result| result);
1143 Ok(()) => EXIT_SUCCESS,
1144 Err(_) => EXIT_FAILURE,
1148 static DEFAULT_HOOK: SyncLazy<Box<dyn Fn(&panic::PanicInfo<'_>) + Sync + Send + 'static>> =
1150 let hook = panic::take_hook();
1151 panic::set_hook(Box::new(|info| {
1152 // Invoke the default handler, which prints the actual panic message and optionally a backtrace
1153 (*DEFAULT_HOOK)(info);
1155 // Separate the output with an empty line
1158 // Print the ICE message
1159 report_ice(info, BUG_REPORT_URL);
1164 /// Prints the ICE message, including query stack, but without backtrace.
1166 /// The message will point the user at `bug_report_url` to report the ICE.
1168 /// When `install_ice_hook` is called, this function will be called as the panic
1170 pub fn report_ice(info: &panic::PanicInfo<'_>, bug_report_url: &str) {
1171 let emitter = Box::new(rustc_errors::emitter::EmitterWriter::stderr(
1172 rustc_errors::ColorConfig::Auto,
1179 let handler = rustc_errors::Handler::with_emitter(true, None, emitter);
1181 // a .span_bug or .bug call has already printed what
1182 // it wants to print.
1183 if !info.payload().is::<rustc_errors::ExplicitBug>() {
1184 let d = rustc_errors::Diagnostic::new(rustc_errors::Level::Bug, "unexpected panic");
1185 handler.emit_diagnostic(&d);
1188 let mut xs: Vec<Cow<'static, str>> = vec![
1189 "the compiler unexpectedly panicked. this is a bug.".into(),
1190 format!("we would appreciate a bug report: {}", bug_report_url).into(),
1192 "rustc {} running on {}",
1193 util::version_str().unwrap_or("unknown_version"),
1194 config::host_triple()
1199 if let Some((flags, excluded_cargo_defaults)) = extra_compiler_flags() {
1200 xs.push(format!("compiler flags: {}", flags.join(" ")).into());
1202 if excluded_cargo_defaults {
1203 xs.push("some of the compiler flags provided by cargo are hidden".into());
1208 handler.note_without_error(note);
1211 // If backtraces are enabled, also print the query stack
1212 let backtrace = env::var_os("RUST_BACKTRACE").map_or(false, |x| &x != "0");
1214 let num_frames = if backtrace { None } else { Some(2) };
1216 interface::try_print_query_stack(&handler, num_frames);
1220 if env::var("RUSTC_BREAK_ON_ICE").is_ok() {
1221 // Trigger a debugger if we crashed during bootstrap
1222 winapi::um::debugapi::DebugBreak();
1227 /// Installs a panic hook that will print the ICE message on unexpected panics.
1229 /// A custom rustc driver can skip calling this to set up a custom ICE hook.
1230 pub fn install_ice_hook() {
1231 // If the user has not explicitly overriden "RUST_BACKTRACE", then produce
1232 // full backtraces. When a compiler ICE happens, we want to gather
1233 // as much information as possible to present in the issue opened
1234 // by the user. Compiler developers and other rustc users can
1235 // opt in to less-verbose backtraces by manually setting "RUST_BACKTRACE"
1236 // (e.g. `RUST_BACKTRACE=1`)
1237 if std::env::var("RUST_BACKTRACE").is_err() {
1238 std::env::set_var("RUST_BACKTRACE", "full");
1240 SyncLazy::force(&DEFAULT_HOOK);
1243 /// This allows tools to enable rust logging without having to magically match rustc's
1244 /// tracing crate version.
1245 pub fn init_rustc_env_logger() {
1246 if let Err(error) = rustc_log::init_rustc_env_logger() {
1247 early_error(ErrorOutputType::default(), &error.to_string());
1251 /// This allows tools to enable rust logging without having to magically match rustc's
1252 /// tracing crate version. In contrast to `init_rustc_env_logger` it allows you to choose an env var
1253 /// other than `RUSTC_LOG`.
1254 pub fn init_env_logger(env: &str) {
1255 if let Err(error) = rustc_log::init_env_logger(env) {
1256 early_error(ErrorOutputType::default(), &error.to_string());
1260 #[cfg(all(unix, any(target_env = "gnu", target_os = "macos")))]
1261 mod signal_handler {
1263 fn backtrace_symbols_fd(
1264 buffer: *const *mut libc::c_void,
1270 extern "C" fn print_stack_trace(_: libc::c_int) {
1271 const MAX_FRAMES: usize = 256;
1272 static mut STACK_TRACE: [*mut libc::c_void; MAX_FRAMES] =
1273 [std::ptr::null_mut(); MAX_FRAMES];
1275 let depth = libc::backtrace(STACK_TRACE.as_mut_ptr(), MAX_FRAMES as i32);
1279 backtrace_symbols_fd(STACK_TRACE.as_ptr(), depth, 2);
1283 // When an error signal (such as SIGABRT or SIGSEGV) is delivered to the
1284 // process, print a stack trace and then exit.
1285 pub(super) fn install() {
1287 const ALT_STACK_SIZE: usize = libc::MINSIGSTKSZ + 64 * 1024;
1288 let mut alt_stack: libc::stack_t = std::mem::zeroed();
1290 std::alloc::alloc(std::alloc::Layout::from_size_align(ALT_STACK_SIZE, 1).unwrap())
1291 as *mut libc::c_void;
1292 alt_stack.ss_size = ALT_STACK_SIZE;
1293 libc::sigaltstack(&alt_stack, std::ptr::null_mut());
1295 let mut sa: libc::sigaction = std::mem::zeroed();
1296 sa.sa_sigaction = print_stack_trace as libc::sighandler_t;
1297 sa.sa_flags = libc::SA_NODEFER | libc::SA_RESETHAND | libc::SA_ONSTACK;
1298 libc::sigemptyset(&mut sa.sa_mask);
1299 libc::sigaction(libc::SIGSEGV, &sa, std::ptr::null_mut());
1304 #[cfg(not(all(unix, any(target_env = "gnu", target_os = "macos"))))]
1305 mod signal_handler {
1306 pub(super) fn install() {}
1309 pub fn main() -> ! {
1310 let start_time = Instant::now();
1311 let start_rss = get_resident_set_size();
1312 init_rustc_env_logger();
1313 signal_handler::install();
1314 let mut callbacks = TimePassesCallbacks::default();
1316 let exit_code = catch_with_exit_code(|| {
1317 let args = env::args_os()
1320 arg.into_string().unwrap_or_else(|arg| {
1322 ErrorOutputType::default(),
1323 &format!("argument {} is not valid Unicode: {:?}", i, arg),
1327 .collect::<Vec<_>>();
1328 RunCompiler::new(&args, &mut callbacks).run()
1331 if callbacks.time_passes {
1332 let end_rss = get_resident_set_size();
1333 print_time_passes_entry("total", start_time.elapsed(), start_rss, end_rss);
1336 process::exit(exit_code)