5 //! This API is completely unstable and subject to change.
7 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
8 #![feature(is_terminal)]
10 #![feature(decl_macro)]
11 #![recursion_limit = "256"]
12 #![allow(rustc::potential_query_instability)]
13 #![deny(rustc::untranslatable_diagnostic)]
14 #![deny(rustc::diagnostic_outside_of_impl)]
19 pub extern crate rustc_plugin_impl as plugin;
22 use rustc_codegen_ssa::{traits::CodegenBackend, CodegenErrors, CodegenResults};
23 use rustc_data_structures::profiling::{get_resident_set_size, print_time_passes_entry};
24 use rustc_data_structures::sync::SeqCst;
25 use rustc_errors::registry::{InvalidErrorCode, Registry};
26 use rustc_errors::{ErrorGuaranteed, PResult};
27 use rustc_feature::find_gated_cfg;
28 use rustc_hir::def_id::LOCAL_CRATE;
29 use rustc_interface::util::{self, collect_crate_types, get_codegen_backend};
30 use rustc_interface::{interface, Queries};
31 use rustc_lint::LintStore;
32 use rustc_metadata::locator;
33 use rustc_save_analysis as save;
34 use rustc_save_analysis::DumpHandler;
35 use rustc_session::config::{nightly_options, CG_OPTIONS, Z_OPTIONS};
36 use rustc_session::config::{ErrorOutputType, Input, OutputType, PrintRequest, TrimmedDefPaths};
37 use rustc_session::cstore::MetadataLoader;
38 use rustc_session::getopts;
39 use rustc_session::lint::{Lint, LintId};
40 use rustc_session::{config, Session};
41 use rustc_session::{early_error, early_error_no_abort, early_warn};
42 use rustc_span::source_map::{FileLoader, FileName};
43 use rustc_span::symbol::sym;
44 use rustc_target::json::ToJson;
48 use std::ffi::OsString;
50 use std::io::{self, IsTerminal, Read, Write};
51 use std::panic::{self, catch_unwind};
52 use std::path::PathBuf;
53 use std::process::{self, Command, Stdio};
55 use std::sync::LazyLock;
56 use std::time::Instant;
60 mod session_diagnostics;
62 use crate::session_diagnostics::{
63 RLinkEmptyVersionNumber, RLinkEncodingVersionMismatch, RLinkRustcVersionMismatch,
64 RLinkWrongFileType, RlinkNotAFile, RlinkUnableToRead,
67 /// Exit status code used for successful compilation and help output.
68 pub const EXIT_SUCCESS: i32 = 0;
70 /// Exit status code used for compilation failures and invalid flags.
71 pub const EXIT_FAILURE: i32 = 1;
73 const BUG_REPORT_URL: &str = "https://github.com/rust-lang/rust/issues/new\
74 ?labels=C-bug%2C+I-ICE%2C+T-compiler&template=ice.md";
76 const ICE_REPORT_COMPILER_FLAGS: &[&str] = &["-Z", "-C", "--crate-type"];
78 const ICE_REPORT_COMPILER_FLAGS_EXCLUDE: &[&str] = &["metadata", "extra-filename"];
80 const ICE_REPORT_COMPILER_FLAGS_STRIP_VALUE: &[&str] = &["incremental"];
82 pub fn abort_on_err<T>(result: Result<T, ErrorGuaranteed>, sess: &Session) -> T {
85 sess.abort_if_errors();
86 panic!("error reported but abort_if_errors didn't abort???");
93 /// Called before creating the compiler instance
94 fn config(&mut self, _config: &mut interface::Config) {}
95 /// Called after parsing. Return value instructs the compiler whether to
96 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
97 fn after_parsing<'tcx>(
99 _compiler: &interface::Compiler,
100 _queries: &'tcx Queries<'tcx>,
102 Compilation::Continue
104 /// Called after expansion. Return value instructs the compiler whether to
105 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
106 fn after_expansion<'tcx>(
108 _compiler: &interface::Compiler,
109 _queries: &'tcx Queries<'tcx>,
111 Compilation::Continue
113 /// Called after analysis. Return value instructs the compiler whether to
114 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
115 fn after_analysis<'tcx>(
117 _compiler: &interface::Compiler,
118 _queries: &'tcx Queries<'tcx>,
120 Compilation::Continue
125 pub struct TimePassesCallbacks {
129 impl Callbacks for TimePassesCallbacks {
130 // JUSTIFICATION: the session doesn't exist at this point.
131 #[allow(rustc::bad_opt_access)]
132 fn config(&mut self, config: &mut interface::Config) {
133 // If a --print=... option has been given, we don't print the "total"
134 // time because it will mess up the --print output. See #64339.
136 self.time_passes = config.opts.prints.is_empty() && config.opts.unstable_opts.time_passes;
137 config.opts.trimmed_def_paths = TrimmedDefPaths::GoodPath;
141 pub fn diagnostics_registry() -> Registry {
142 Registry::new(rustc_error_codes::DIAGNOSTICS)
145 /// This is the primary entry point for rustc.
146 pub struct RunCompiler<'a, 'b> {
147 at_args: &'a [String],
148 callbacks: &'b mut (dyn Callbacks + Send),
149 file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
150 make_codegen_backend:
151 Option<Box<dyn FnOnce(&config::Options) -> Box<dyn CodegenBackend> + Send>>,
154 impl<'a, 'b> RunCompiler<'a, 'b> {
155 pub fn new(at_args: &'a [String], callbacks: &'b mut (dyn Callbacks + Send)) -> Self {
156 Self { at_args, callbacks, file_loader: None, make_codegen_backend: None }
159 /// Set a custom codegen backend.
161 /// Has no uses within this repository, but is used by bjorn3 for "the
162 /// hotswapping branch of cg_clif" for "setting the codegen backend from a
163 /// custom driver where the custom codegen backend has arbitrary data."
165 pub fn set_make_codegen_backend(
167 make_codegen_backend: Option<
168 Box<dyn FnOnce(&config::Options) -> Box<dyn CodegenBackend> + Send>,
171 self.make_codegen_backend = make_codegen_backend;
175 /// Load files from sources other than the file system.
177 /// Has no uses within this repository, but may be used in the future by
178 /// bjorn3 for "hooking rust-analyzer's VFS into rustc at some point for
179 /// running rustc without having to save". (See #102759.)
180 pub fn set_file_loader(
182 file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
184 self.file_loader = file_loader;
188 /// Parse args and run the compiler.
189 pub fn run(self) -> interface::Result<()> {
190 run_compiler(self.at_args, self.callbacks, self.file_loader, self.make_codegen_backend)
196 callbacks: &mut (dyn Callbacks + Send),
197 file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
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 Some(matches) = handle_options(&args) else { return Ok(()) };
206 let sopts = config::build_session_options(&matches);
208 if let Some(ref code) = matches.opt_str("explain") {
209 handle_explain(diagnostics_registry(), code, sopts.error_format);
213 let cfg = interface::parse_cfgspecs(matches.opt_strs("cfg"));
214 let check_cfg = interface::parse_check_cfg(matches.opt_strs("check-cfg"));
215 let (odir, ofile) = make_output(&matches);
216 let mut config = interface::Config {
219 crate_check_cfg: check_cfg,
220 input: Input::File(PathBuf::new()),
224 lint_caps: Default::default(),
225 parse_sess_created: None,
226 register_lints: None,
227 override_queries: None,
228 make_codegen_backend,
229 registry: diagnostics_registry(),
232 if !tracing::dispatcher::has_been_set() {
233 init_rustc_env_logger_with_backtrace_option(&config.opts.unstable_opts.log_backtrace);
236 match make_input(config.opts.error_format, &matches.free) {
237 Err(reported) => return Err(reported),
239 config.input = input;
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 {
250 rustc_lint::new_lint_store(compiler.session().enable_internal_lints());
251 let registered_lints =
252 if let Some(register_lints) = compiler.register_lints() {
253 register_lints(compiler.session(), &mut lint_store);
258 describe_lints(compiler.session(), &lint_store, registered_lints);
262 print_crate_info(&***compiler.codegen_backend(), compiler.session(), false);
264 if should_stop == Compilation::Stop {
267 early_error(sopts.error_format, "no input filename given")
271 1 => panic!("make_input should have provided valid inputs"),
273 config.opts.error_format,
275 "multiple input filenames provided (first two filenames are `{}` and `{}`)",
276 matches.free[0], matches.free[1],
282 interface::run_compiler(config, |compiler| {
283 let sess = compiler.session();
284 let should_stop = print_crate_info(&***compiler.codegen_backend(), sess, true)
285 .and_then(|| list_metadata(sess, &*compiler.codegen_backend().metadata_loader()))
286 .and_then(|| try_process_rlink(sess, compiler));
288 if should_stop == Compilation::Stop {
289 return sess.compile_status();
292 let linker = compiler.enter(|queries| {
293 let early_exit = || sess.compile_status().map(|_| None);
296 if let Some(ppm) = &sess.opts.pretty {
297 if ppm.needs_ast_map() {
298 queries.global_ctxt()?.enter(|tcx| {
299 pretty::print_after_hir_lowering(tcx, *ppm);
303 let krate = queries.parse()?.steal();
304 pretty::print_after_parsing(sess, &krate, *ppm);
306 trace!("finished pretty-printing");
310 if callbacks.after_parsing(compiler, queries) == Compilation::Stop {
314 if sess.opts.unstable_opts.parse_only || sess.opts.unstable_opts.show_span.is_some() {
319 let plugins = queries.register_plugins()?;
320 let (_, lint_store) = &*plugins.borrow();
322 // Lint plugins are registered; now we can process command line flags.
323 if sess.opts.describe_lints {
324 describe_lints(sess, lint_store, true);
329 let mut gctxt = queries.global_ctxt()?;
330 if callbacks.after_expansion(compiler, queries) == Compilation::Stop {
334 // Make sure the `output_filenames` query is run for its side
335 // effects of writing the dep-info and reporting errors.
336 gctxt.enter(|tcx| tcx.output_filenames(()));
338 if sess.opts.output_types.contains_key(&OutputType::DepInfo)
339 && sess.opts.output_types.len() == 1
344 if sess.opts.unstable_opts.no_analysis {
349 let result = tcx.analysis(());
350 if sess.opts.unstable_opts.save_analysis {
351 let crate_name = tcx.crate_name(LOCAL_CRATE);
352 sess.time("save_analysis", || {
358 DumpHandler::new(sess.io.output_dir.as_deref(), crate_name),
367 if callbacks.after_analysis(compiler, queries) == Compilation::Stop {
371 queries.ongoing_codegen()?;
373 if sess.opts.unstable_opts.print_type_sizes {
374 sess.code_stats.print_type_sizes();
377 let linker = queries.linker()?;
381 if let Some(linker) = linker {
382 let _timer = sess.timer("link");
386 if sess.opts.unstable_opts.perf_stats {
387 sess.print_perf_stats();
390 if sess.opts.unstable_opts.print_fuel.is_some() {
392 "Fuel used by {}: {}",
393 sess.opts.unstable_opts.print_fuel.as_ref().unwrap(),
394 sess.print_fuel.load(SeqCst)
402 // Extract output directory and file from matches.
403 fn make_output(matches: &getopts::Matches) -> (Option<PathBuf>, Option<PathBuf>) {
404 let odir = matches.opt_str("out-dir").map(|o| PathBuf::from(&o));
405 let ofile = matches.opt_str("o").map(|o| PathBuf::from(&o));
409 // Extract input (string or file and optional path) from matches.
411 error_format: ErrorOutputType,
412 free_matches: &[String],
413 ) -> Result<Option<Input>, ErrorGuaranteed> {
414 if free_matches.len() == 1 {
415 let ifile = &free_matches[0];
417 let mut src = String::new();
418 if io::stdin().read_to_string(&mut src).is_err() {
419 // Immediately stop compilation if there was an issue reading
420 // the input (for example if the input stream is not UTF-8).
421 let reported = early_error_no_abort(
423 "couldn't read from stdin, as it did not contain valid UTF-8",
425 return Err(reported);
427 if let Ok(path) = env::var("UNSTABLE_RUSTDOC_TEST_PATH") {
428 let line = env::var("UNSTABLE_RUSTDOC_TEST_LINE").expect(
429 "when UNSTABLE_RUSTDOC_TEST_PATH is set \
430 UNSTABLE_RUSTDOC_TEST_LINE also needs to be set",
432 let line = isize::from_str_radix(&line, 10)
433 .expect("UNSTABLE_RUSTDOC_TEST_LINE needs to be an number");
434 let file_name = FileName::doc_test_source_code(PathBuf::from(path), line);
435 Ok(Some(Input::Str { name: file_name, input: src }))
437 Ok(Some(Input::Str { name: FileName::anon_source_code(&src), input: src }))
440 Ok(Some(Input::File(PathBuf::from(ifile))))
447 /// Whether to stop or continue compilation.
448 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
449 pub enum Compilation {
455 pub fn and_then<F: FnOnce() -> Compilation>(self, next: F) -> Compilation {
457 Compilation::Stop => Compilation::Stop,
458 Compilation::Continue => next(),
463 fn handle_explain(registry: Registry, code: &str, output: ErrorOutputType) {
464 let upper_cased_code = code.to_ascii_uppercase();
466 if upper_cased_code.starts_with('E') { upper_cased_code } else { format!("E{code:0>4}") };
467 match registry.try_find_description(&normalised) {
468 Ok(Some(description)) => {
469 let mut is_in_code_block = false;
470 let mut text = String::new();
471 // Slice off the leading newline and print.
472 for line in description.lines() {
474 line.find(|c: char| !c.is_whitespace()).unwrap_or_else(|| line.len());
475 let dedented_line = &line[indent_level..];
476 if dedented_line.starts_with("```") {
477 is_in_code_block = !is_in_code_block;
478 text.push_str(&line[..(indent_level + 3)]);
479 } else if is_in_code_block && dedented_line.starts_with("# ") {
486 if io::stdout().is_terminal() {
487 show_content_with_pager(&text);
493 early_error(output, &format!("no extended information for {code}"));
495 Err(InvalidErrorCode) => {
496 early_error(output, &format!("{code} is not a valid error code"));
501 fn show_content_with_pager(content: &str) {
502 let pager_name = env::var_os("PAGER").unwrap_or_else(|| {
503 if cfg!(windows) { OsString::from("more.com") } else { OsString::from("less") }
506 let mut fallback_to_println = false;
508 match Command::new(pager_name).stdin(Stdio::piped()).spawn() {
510 if let Some(pipe) = pager.stdin.as_mut() {
511 if pipe.write_all(content.as_bytes()).is_err() {
512 fallback_to_println = true;
516 if pager.wait().is_err() {
517 fallback_to_println = true;
521 fallback_to_println = true;
525 // If pager fails for whatever reason, we should still print the content
526 // to standard output
527 if fallback_to_println {
532 pub fn try_process_rlink(sess: &Session, compiler: &interface::Compiler) -> Compilation {
533 if sess.opts.unstable_opts.link_only {
534 if let Input::File(file) = &sess.io.input {
535 // FIXME: #![crate_type] and #![crate_name] support not implemented yet
536 sess.init_crate_types(collect_crate_types(sess, &[]));
537 let outputs = compiler.build_output_filenames(sess, &[]);
538 let rlink_data = fs::read(file).unwrap_or_else(|err| {
539 sess.emit_fatal(RlinkUnableToRead { err });
541 let codegen_results = match CodegenResults::deserialize_rlink(rlink_data) {
542 Ok(codegen) => codegen,
545 CodegenErrors::WrongFileType => sess.emit_fatal(RLinkWrongFileType),
546 CodegenErrors::EmptyVersionNumber => {
547 sess.emit_fatal(RLinkEmptyVersionNumber)
549 CodegenErrors::EncodingVersionMismatch { version_array, rlink_version } => {
550 sess.emit_fatal(RLinkEncodingVersionMismatch {
555 CodegenErrors::RustcVersionMismatch { rustc_version, current_version } => {
556 sess.emit_fatal(RLinkRustcVersionMismatch {
564 let result = compiler.codegen_backend().link(sess, codegen_results, &outputs);
565 abort_on_err(result, sess);
567 sess.emit_fatal(RlinkNotAFile {})
571 Compilation::Continue
575 pub fn list_metadata(sess: &Session, metadata_loader: &dyn MetadataLoader) -> Compilation {
576 if sess.opts.unstable_opts.ls {
577 match sess.io.input {
578 Input::File(ref ifile) => {
579 let path = &(*ifile);
580 let mut v = Vec::new();
581 locator::list_file_metadata(&sess.target, path, metadata_loader, &mut v).unwrap();
582 println!("{}", String::from_utf8(v).unwrap());
584 Input::Str { .. } => {
585 early_error(ErrorOutputType::default(), "cannot list metadata for stdin");
588 return Compilation::Stop;
591 Compilation::Continue
595 codegen_backend: &dyn CodegenBackend,
599 use rustc_session::config::PrintRequest::*;
600 // NativeStaticLibs and LinkArgs are special - printed during linking
601 // (empty iterator returns true)
602 if sess.opts.prints.iter().all(|&p| p == NativeStaticLibs || p == LinkArgs) {
603 return Compilation::Continue;
606 let attrs = if parse_attrs {
607 let result = parse_crate_attrs(sess);
609 Ok(attrs) => Some(attrs),
610 Err(mut parse_error) => {
612 return Compilation::Stop;
618 for req in &sess.opts.prints {
621 let mut targets = rustc_target::spec::TARGETS.to_vec();
622 targets.sort_unstable();
623 println!("{}", targets.join("\n"));
625 Sysroot => println!("{}", sess.sysroot.display()),
626 TargetLibdir => println!("{}", sess.target_tlib_path.dir.display()),
628 println!("{}", serde_json::to_string_pretty(&sess.target.to_json()).unwrap());
630 FileNames | CrateName => {
631 let attrs = attrs.as_ref().unwrap();
632 let t_outputs = rustc_interface::util::build_output_filenames(attrs, sess);
633 let id = rustc_session::output::find_crate_name(sess, attrs);
634 if *req == PrintRequest::CrateName {
638 let crate_types = collect_crate_types(sess, attrs);
639 for &style in &crate_types {
641 rustc_session::output::filename_for_input(sess, style, id, &t_outputs);
642 println!("{}", fname.file_name().unwrap().to_string_lossy());
650 .filter_map(|&(name, value)| {
651 // Note that crt-static is a specially recognized cfg
652 // directive that's printed out here as part of
653 // rust-lang/rust#37406, but in general the
654 // `target_feature` cfg is gated under
655 // rust-lang/rust#29717. For now this is just
656 // specifically allowing the crt-static cfg and that's
657 // it, this is intended to get into Cargo and then go
658 // through to build scripts.
659 if (name != sym::target_feature || value != Some(sym::crt_dash_static))
660 && !sess.is_nightly_build()
661 && find_gated_cfg(|cfg_sym| cfg_sym == name).is_some()
666 if let Some(value) = value {
667 Some(format!("{name}=\"{value}\""))
669 Some(name.to_string())
672 .collect::<Vec<String>>();
679 CallingConventions => {
680 let mut calling_conventions = rustc_target::spec::abi::all_names();
681 calling_conventions.sort_unstable();
682 println!("{}", calling_conventions.join("\n"));
688 | StackProtectorStrategies
689 | TargetFeatures => {
690 codegen_backend.print(*req, sess);
692 // Any output here interferes with Cargo's parsing of other printed output
693 NativeStaticLibs => {}
696 use rustc_target::spec::SplitDebuginfo::{Off, Packed, Unpacked};
698 for split in &[Off, Packed, Unpacked] {
699 let stable = sess.target.options.supported_split_debuginfo.contains(split);
700 let unstable_ok = sess.unstable_options();
701 if stable || unstable_ok {
711 /// Prints version information
713 /// NOTE: this is a macro to support drivers built at a different time than the main `rustc_driver` crate.
714 pub macro version($binary: literal, $matches: expr) {
715 fn unw(x: Option<&str>) -> &str {
716 x.unwrap_or("unknown")
718 $crate::version_at_macro_invocation(
721 unw(option_env!("CFG_VERSION")),
722 unw(option_env!("CFG_VER_HASH")),
723 unw(option_env!("CFG_VER_DATE")),
724 unw(option_env!("CFG_RELEASE")),
728 #[doc(hidden)] // use the macro instead
729 pub fn version_at_macro_invocation(
731 matches: &getopts::Matches,
737 let verbose = matches.opt_present("verbose");
739 println!("{binary} {version}");
742 println!("binary: {binary}");
743 println!("commit-hash: {commit_hash}");
744 println!("commit-date: {commit_date}");
745 println!("host: {}", config::host_triple());
746 println!("release: {release}");
748 let debug_flags = matches.opt_strs("Z");
749 let backend_name = debug_flags.iter().find_map(|x| x.strip_prefix("codegen-backend="));
750 get_codegen_backend(&None, backend_name).print_version();
754 fn usage(verbose: bool, include_unstable_options: bool, nightly_build: bool) {
755 let groups = if verbose { config::rustc_optgroups() } else { config::rustc_short_optgroups() };
756 let mut options = getopts::Options::new();
757 for option in groups.iter().filter(|x| include_unstable_options || x.is_stable()) {
758 (option.apply)(&mut options);
760 let message = "Usage: rustc [OPTIONS] INPUT";
761 let nightly_help = if nightly_build {
762 "\n -Z help Print unstable compiler options"
766 let verbose_help = if verbose {
769 "\n --help -v Print the full set of options rustc accepts"
771 let at_path = if verbose {
772 " @path Read newline separated options from `path`\n"
777 "{options}{at_path}\nAdditional help:
778 -C help Print codegen options
780 Print 'lint' options and default settings{nightly}{verbose}\n",
781 options = options.usage(message),
783 nightly = nightly_help,
784 verbose = verbose_help
788 fn print_wall_help() {
791 The flag `-Wall` does not exist in `rustc`. Most useful lints are enabled by
792 default. Use `rustc -W help` to see all available lints. It's more common to put
793 warning settings in the crate root using `#![warn(LINT_NAME)]` instead of using
794 the command line flag directly.
799 /// Write to stdout lint command options, together with a list of all available lints
800 pub fn describe_lints(sess: &Session, lint_store: &LintStore, loaded_plugins: bool) {
803 Available lint options:
804 -W <foo> Warn about <foo>
808 -F <foo> Forbid <foo> \
809 (deny <foo> and all attempts to override)
814 fn sort_lints(sess: &Session, mut lints: Vec<&'static Lint>) -> Vec<&'static Lint> {
815 // The sort doesn't case-fold but it's doubtful we care.
816 lints.sort_by_cached_key(|x: &&Lint| (x.default_level(sess.edition()), x.name));
821 lints: Vec<(&'static str, Vec<LintId>, bool)>,
822 ) -> Vec<(&'static str, Vec<LintId>)> {
823 let mut lints: Vec<_> = lints.into_iter().map(|(x, y, _)| (x, y)).collect();
824 lints.sort_by_key(|l| l.0);
828 let (plugin, builtin): (Vec<_>, _) =
829 lint_store.get_lints().iter().cloned().partition(|&lint| lint.is_plugin);
830 let plugin = sort_lints(sess, plugin);
831 let builtin = sort_lints(sess, builtin);
833 let (plugin_groups, builtin_groups): (Vec<_>, _) =
834 lint_store.get_lint_groups().partition(|&(.., p)| p);
835 let plugin_groups = sort_lint_groups(plugin_groups);
836 let builtin_groups = sort_lint_groups(builtin_groups);
839 plugin.iter().chain(&builtin).map(|&s| s.name.chars().count()).max().unwrap_or(0);
840 let padded = |x: &str| {
841 let mut s = " ".repeat(max_name_len - x.chars().count());
846 println!("Lint checks provided by rustc:\n");
848 let print_lints = |lints: Vec<&Lint>| {
849 println!(" {} {:7.7} {}", padded("name"), "default", "meaning");
850 println!(" {} {:7.7} {}", padded("----"), "-------", "-------");
852 let name = lint.name_lower().replace('_', "-");
856 lint.default_level(sess.edition()).as_str(),
863 print_lints(builtin);
865 let max_name_len = max(
869 .chain(&builtin_groups)
870 .map(|&(s, _)| s.chars().count())
875 let padded = |x: &str| {
876 let mut s = " ".repeat(max_name_len - x.chars().count());
881 println!("Lint groups provided by rustc:\n");
883 let print_lint_groups = |lints: Vec<(&'static str, Vec<LintId>)>, all_warnings| {
884 println!(" {} sub-lints", padded("name"));
885 println!(" {} ---------", padded("----"));
888 println!(" {} all lints that are set to issue warnings", padded("warnings"));
891 for (name, to) in lints {
892 let name = name.to_lowercase().replace('_', "-");
895 .map(|x| x.to_string().replace('_', "-"))
896 .collect::<Vec<String>>()
898 println!(" {} {}", padded(&name), desc);
903 print_lint_groups(builtin_groups, true);
905 match (loaded_plugins, plugin.len(), plugin_groups.len()) {
906 (false, 0, _) | (false, _, 0) => {
907 println!("Lint tools like Clippy can provide additional lints and lint groups.");
909 (false, ..) => panic!("didn't load lint plugins but got them anyway!"),
910 (true, 0, 0) => println!("This crate does not load any lint plugins or lint groups."),
913 println!("Lint checks provided by plugins loaded by this crate:\n");
917 println!("Lint groups provided by plugins loaded by this crate:\n");
918 print_lint_groups(plugin_groups, false);
924 fn describe_debug_flags() {
925 println!("\nAvailable options:\n");
926 print_flag_list("-Z", config::Z_OPTIONS);
929 fn describe_codegen_flags() {
930 println!("\nAvailable codegen options:\n");
931 print_flag_list("-C", config::CG_OPTIONS);
934 pub fn print_flag_list<T>(
936 flag_list: &[(&'static str, T, &'static str, &'static str)],
938 let max_len = flag_list.iter().map(|&(name, _, _, _)| name.chars().count()).max().unwrap_or(0);
940 for &(name, _, _, desc) in flag_list {
942 " {} {:>width$}=val -- {}",
944 name.replace('_', "-"),
951 /// Process command line options. Emits messages as appropriate. If compilation
952 /// should continue, returns a getopts::Matches object parsed from args,
953 /// otherwise returns `None`.
955 /// The compiler's handling of options is a little complicated as it ties into
956 /// our stability story. The current intention of each compiler option is to
957 /// have one of two modes:
959 /// 1. An option is stable and can be used everywhere.
960 /// 2. An option is unstable, and can only be used on nightly.
962 /// Like unstable library and language features, however, unstable options have
963 /// always required a form of "opt in" to indicate that you're using them. This
964 /// provides the easy ability to scan a code base to check to see if anything
965 /// unstable is being used. Currently, this "opt in" is the `-Z` "zed" flag.
967 /// All options behind `-Z` are considered unstable by default. Other top-level
968 /// options can also be considered unstable, and they were unlocked through the
969 /// `-Z unstable-options` flag. Note that `-Z` remains to be the root of
970 /// instability in both cases, though.
972 /// So with all that in mind, the comments below have some more detail about the
973 /// contortions done here to get things to work out correctly.
974 pub fn handle_options(args: &[String]) -> Option<getopts::Matches> {
975 // Throw away the first argument, the name of the binary
976 let args = &args[1..];
979 // user did not write `-v` nor `-Z unstable-options`, so do not
980 // include that extra information.
982 rustc_feature::UnstableFeatures::from_environment(None).is_nightly_build();
983 usage(false, false, nightly_build);
987 // Parse with *all* options defined in the compiler, we don't worry about
988 // option stability here we just want to parse as much as possible.
989 let mut options = getopts::Options::new();
990 for option in config::rustc_optgroups() {
991 (option.apply)(&mut options);
993 let matches = options.parse(args).unwrap_or_else(|e| {
995 getopts::Fail::UnrecognizedOption(ref opt) => CG_OPTIONS
997 .map(|&(name, ..)| ('C', name))
998 .chain(Z_OPTIONS.iter().map(|&(name, ..)| ('Z', name)))
999 .find(|&(_, name)| *opt == name.replace('_', "-"))
1000 .map(|(flag, _)| format!("{e}. Did you mean `-{flag} {opt}`?")),
1003 early_error(ErrorOutputType::default(), &msg.unwrap_or_else(|| e.to_string()));
1006 // For all options we just parsed, we check a few aspects:
1008 // * If the option is stable, we're all good
1009 // * If the option wasn't passed, we're all good
1010 // * If `-Z unstable-options` wasn't passed (and we're not a -Z option
1011 // ourselves), then we require the `-Z unstable-options` flag to unlock
1012 // this option that was passed.
1013 // * If we're a nightly compiler, then unstable options are now unlocked, so
1014 // we're good to go.
1015 // * Otherwise, if we're an unstable option then we generate an error
1016 // (unstable option being used on stable)
1017 nightly_options::check_nightly_options(&matches, &config::rustc_optgroups());
1019 if matches.opt_present("h") || matches.opt_present("help") {
1020 // Only show unstable options in --help if we accept unstable options.
1021 let unstable_enabled = nightly_options::is_unstable_enabled(&matches);
1022 let nightly_build = nightly_options::match_is_nightly_build(&matches);
1023 usage(matches.opt_present("verbose"), unstable_enabled, nightly_build);
1027 // Handle the special case of -Wall.
1028 let wall = matches.opt_strs("W");
1029 if wall.iter().any(|x| *x == "all") {
1031 rustc_errors::FatalError.raise();
1034 // Don't handle -W help here, because we might first load plugins.
1035 let debug_flags = matches.opt_strs("Z");
1036 if debug_flags.iter().any(|x| *x == "help") {
1037 describe_debug_flags();
1041 let cg_flags = matches.opt_strs("C");
1043 if cg_flags.iter().any(|x| *x == "help") {
1044 describe_codegen_flags();
1048 if cg_flags.iter().any(|x| *x == "no-stack-check") {
1050 ErrorOutputType::default(),
1051 "the --no-stack-check flag is deprecated and does nothing",
1055 if cg_flags.iter().any(|x| *x == "passes=list") {
1056 let backend_name = debug_flags.iter().find_map(|x| x.strip_prefix("codegen-backend="));
1057 get_codegen_backend(&None, backend_name).print_passes();
1061 if matches.opt_present("version") {
1062 version!("rustc", &matches);
1069 fn parse_crate_attrs<'a>(sess: &'a Session) -> PResult<'a, ast::AttrVec> {
1070 match &sess.io.input {
1071 Input::File(ifile) => rustc_parse::parse_crate_attrs_from_file(ifile, &sess.parse_sess),
1072 Input::Str { name, input } => rustc_parse::parse_crate_attrs_from_source_str(
1080 /// Gets a list of extra command-line flags provided by the user, as strings.
1082 /// This function is used during ICEs to show more information useful for
1083 /// debugging, since some ICEs only happens with non-default compiler flags
1084 /// (and the users don't always report them).
1085 fn extra_compiler_flags() -> Option<(Vec<String>, bool)> {
1086 let mut args = env::args_os().map(|arg| arg.to_string_lossy().to_string()).peekable();
1088 let mut result = Vec::new();
1089 let mut excluded_cargo_defaults = false;
1090 while let Some(arg) = args.next() {
1091 if let Some(a) = ICE_REPORT_COMPILER_FLAGS.iter().find(|a| arg.starts_with(*a)) {
1092 let content = if arg.len() == a.len() {
1093 // A space-separated option, like `-C incremental=foo` or `--crate-type rlib`
1095 Some(arg) => arg.to_string(),
1098 } else if arg.get(a.len()..a.len() + 1) == Some("=") {
1099 // An equals option, like `--crate-type=rlib`
1100 arg[a.len() + 1..].to_string()
1102 // A non-space option, like `-Cincremental=foo`
1103 arg[a.len()..].to_string()
1105 let option = content.split_once('=').map(|s| s.0).unwrap_or(&content);
1106 if ICE_REPORT_COMPILER_FLAGS_EXCLUDE.iter().any(|exc| option == *exc) {
1107 excluded_cargo_defaults = true;
1109 result.push(a.to_string());
1110 match ICE_REPORT_COMPILER_FLAGS_STRIP_VALUE.iter().find(|s| option == **s) {
1111 Some(s) => result.push(format!("{s}=[REDACTED]")),
1112 None => result.push(content),
1118 if !result.is_empty() { Some((result, excluded_cargo_defaults)) } else { None }
1121 /// Runs a closure and catches unwinds triggered by fatal errors.
1123 /// The compiler currently unwinds with a special sentinel value to abort
1124 /// compilation on fatal errors. This function catches that sentinel and turns
1125 /// the panic into a `Result` instead.
1126 pub fn catch_fatal_errors<F: FnOnce() -> R, R>(f: F) -> Result<R, ErrorGuaranteed> {
1127 catch_unwind(panic::AssertUnwindSafe(f)).map_err(|value| {
1128 if value.is::<rustc_errors::FatalErrorMarker>() {
1129 ErrorGuaranteed::unchecked_claim_error_was_emitted()
1131 panic::resume_unwind(value);
1136 /// Variant of `catch_fatal_errors` for the `interface::Result` return type
1137 /// that also computes the exit code.
1138 pub fn catch_with_exit_code(f: impl FnOnce() -> interface::Result<()>) -> i32 {
1139 let result = catch_fatal_errors(f).and_then(|result| result);
1141 Ok(()) => EXIT_SUCCESS,
1142 Err(_) => EXIT_FAILURE,
1146 static DEFAULT_HOOK: LazyLock<Box<dyn Fn(&panic::PanicInfo<'_>) + Sync + Send + 'static>> =
1148 let hook = panic::take_hook();
1149 panic::set_hook(Box::new(|info| {
1150 // If the error was caused by a broken pipe then this is not a bug.
1151 // Write the error and return immediately. See #98700.
1153 if let Some(msg) = info.payload().downcast_ref::<String>() {
1154 if msg.starts_with("failed printing to stdout: ") && msg.ends_with("(os error 232)")
1156 early_error_no_abort(ErrorOutputType::default(), &msg);
1161 // Invoke the default handler, which prints the actual panic message and optionally a backtrace
1162 // Don't do this for delayed bugs, which already emit their own more useful backtrace.
1163 if !info.payload().is::<rustc_errors::DelayedBugPanic>() {
1164 (*DEFAULT_HOOK)(info);
1166 // Separate the output with an empty line
1170 // Print the ICE message
1171 report_ice(info, BUG_REPORT_URL);
1176 /// Prints the ICE message, including query stack, but without backtrace.
1178 /// The message will point the user at `bug_report_url` to report the ICE.
1180 /// When `install_ice_hook` is called, this function will be called as the panic
1182 pub fn report_ice(info: &panic::PanicInfo<'_>, bug_report_url: &str) {
1183 let fallback_bundle =
1184 rustc_errors::fallback_fluent_bundle(rustc_errors::DEFAULT_LOCALE_RESOURCES, false);
1185 let emitter = Box::new(rustc_errors::emitter::EmitterWriter::stderr(
1186 rustc_errors::ColorConfig::Auto,
1196 let handler = rustc_errors::Handler::with_emitter(true, None, emitter);
1198 // a .span_bug or .bug call has already printed what
1199 // it wants to print.
1200 if !info.payload().is::<rustc_errors::ExplicitBug>()
1201 && !info.payload().is::<rustc_errors::DelayedBugPanic>()
1203 let mut d = rustc_errors::Diagnostic::new(rustc_errors::Level::Bug, "unexpected panic");
1204 handler.emit_diagnostic(&mut d);
1207 handler.emit_note(session_diagnostics::Ice);
1208 handler.emit_note(session_diagnostics::IceBugReport { bug_report_url });
1209 handler.emit_note(session_diagnostics::IceVersion {
1210 version: util::version_str!().unwrap_or("unknown_version"),
1211 triple: config::host_triple(),
1214 if let Some((flags, excluded_cargo_defaults)) = extra_compiler_flags() {
1215 handler.emit_note(session_diagnostics::IceFlags { flags: flags.join(" ") });
1216 if excluded_cargo_defaults {
1217 handler.emit_note(session_diagnostics::IceExcludeCargoDefaults);
1221 // If backtraces are enabled, also print the query stack
1222 let backtrace = env::var_os("RUST_BACKTRACE").map_or(false, |x| &x != "0");
1224 let num_frames = if backtrace { None } else { Some(2) };
1226 interface::try_print_query_stack(&handler, num_frames);
1230 if env::var("RUSTC_BREAK_ON_ICE").is_ok() {
1231 // Trigger a debugger if we crashed during bootstrap
1232 winapi::um::debugapi::DebugBreak();
1237 /// Installs a panic hook that will print the ICE message on unexpected panics.
1239 /// A custom rustc driver can skip calling this to set up a custom ICE hook.
1240 pub fn install_ice_hook() {
1241 // If the user has not explicitly overridden "RUST_BACKTRACE", then produce
1242 // full backtraces. When a compiler ICE happens, we want to gather
1243 // as much information as possible to present in the issue opened
1244 // by the user. Compiler developers and other rustc users can
1245 // opt in to less-verbose backtraces by manually setting "RUST_BACKTRACE"
1246 // (e.g. `RUST_BACKTRACE=1`)
1247 if std::env::var("RUST_BACKTRACE").is_err() {
1248 std::env::set_var("RUST_BACKTRACE", "full");
1250 LazyLock::force(&DEFAULT_HOOK);
1253 /// This allows tools to enable rust logging without having to magically match rustc's
1254 /// tracing crate version.
1255 pub fn init_rustc_env_logger() {
1256 init_rustc_env_logger_with_backtrace_option(&None);
1259 /// This allows tools to enable rust logging without having to magically match rustc's
1260 /// tracing crate version. In contrast to `init_rustc_env_logger` it allows you to
1261 /// choose a target module you wish to show backtraces along with its logging.
1262 pub fn init_rustc_env_logger_with_backtrace_option(backtrace_target: &Option<String>) {
1263 if let Err(error) = rustc_log::init_rustc_env_logger_with_backtrace_option(backtrace_target) {
1264 early_error(ErrorOutputType::default(), &error.to_string());
1268 /// This allows tools to enable rust logging without having to magically match rustc's
1269 /// tracing crate version. In contrast to `init_rustc_env_logger` it allows you to choose an env var
1270 /// other than `RUSTC_LOG`.
1271 pub fn init_env_logger(env: &str) {
1272 if let Err(error) = rustc_log::init_env_logger(env) {
1273 early_error(ErrorOutputType::default(), &error.to_string());
1277 #[cfg(all(unix, any(target_env = "gnu", target_os = "macos")))]
1278 mod signal_handler {
1280 fn backtrace_symbols_fd(
1281 buffer: *const *mut libc::c_void,
1287 extern "C" fn print_stack_trace(_: libc::c_int) {
1288 const MAX_FRAMES: usize = 256;
1289 static mut STACK_TRACE: [*mut libc::c_void; MAX_FRAMES] =
1290 [std::ptr::null_mut(); MAX_FRAMES];
1292 let depth = libc::backtrace(STACK_TRACE.as_mut_ptr(), MAX_FRAMES as i32);
1296 backtrace_symbols_fd(STACK_TRACE.as_ptr(), depth, 2);
1300 /// When an error signal (such as SIGABRT or SIGSEGV) is delivered to the
1301 /// process, print a stack trace and then exit.
1302 pub(super) fn install() {
1304 const ALT_STACK_SIZE: usize = libc::MINSIGSTKSZ + 64 * 1024;
1305 let mut alt_stack: libc::stack_t = std::mem::zeroed();
1307 std::alloc::alloc(std::alloc::Layout::from_size_align(ALT_STACK_SIZE, 1).unwrap())
1308 as *mut libc::c_void;
1309 alt_stack.ss_size = ALT_STACK_SIZE;
1310 libc::sigaltstack(&alt_stack, std::ptr::null_mut());
1312 let mut sa: libc::sigaction = std::mem::zeroed();
1313 sa.sa_sigaction = print_stack_trace as libc::sighandler_t;
1314 sa.sa_flags = libc::SA_NODEFER | libc::SA_RESETHAND | libc::SA_ONSTACK;
1315 libc::sigemptyset(&mut sa.sa_mask);
1316 libc::sigaction(libc::SIGSEGV, &sa, std::ptr::null_mut());
1321 #[cfg(not(all(unix, any(target_env = "gnu", target_os = "macos"))))]
1322 mod signal_handler {
1323 pub(super) fn install() {}
1326 pub fn main() -> ! {
1327 let start_time = Instant::now();
1328 let start_rss = get_resident_set_size();
1329 signal_handler::install();
1330 let mut callbacks = TimePassesCallbacks::default();
1332 let exit_code = catch_with_exit_code(|| {
1333 let args = env::args_os()
1336 arg.into_string().unwrap_or_else(|arg| {
1338 ErrorOutputType::default(),
1339 &format!("argument {i} is not valid Unicode: {arg:?}"),
1343 .collect::<Vec<_>>();
1344 RunCompiler::new(&args, &mut callbacks).run()
1347 if callbacks.time_passes {
1348 let end_rss = get_resident_set_size();
1349 print_time_passes_entry("total", start_time.elapsed(), start_rss, end_rss);
1352 process::exit(exit_code)