5 //! This API is completely unstable and subject to change.
7 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/")]
9 #![recursion_limit = "256"]
11 pub extern crate getopts;
17 extern crate lazy_static;
19 pub extern crate rustc_plugin_impl as plugin;
22 use rustc_codegen_ssa::{traits::CodegenBackend, CodegenResults};
23 use rustc_data_structures::profiling::print_time_passes_entry;
24 use rustc_data_structures::sync::SeqCst;
25 use rustc_errors::registry::{InvalidErrorCode, Registry};
26 use rustc_errors::{ErrorReported, PResult};
27 use rustc_feature::{find_gated_cfg, UnstableFeatures};
28 use rustc_hir::def_id::LOCAL_CRATE;
29 use rustc_interface::util::{collect_crate_types, get_builtin_codegen_backend};
30 use rustc_interface::{interface, Queries};
31 use rustc_lint::LintStore;
32 use rustc_metadata::locator;
33 use rustc_middle::middle::cstore::MetadataLoader;
34 use rustc_middle::ty::TyCtxt;
35 use rustc_save_analysis as save;
36 use rustc_save_analysis::DumpHandler;
37 use rustc_serialize::json::{self, ToJson};
38 use rustc_session::config::nightly_options;
39 use rustc_session::config::{ErrorOutputType, Input, OutputType, PrintRequest};
40 use rustc_session::lint::{Lint, LintId};
41 use rustc_session::{config, DiagnosticOutput, Session};
42 use rustc_session::{early_error, early_warn};
43 use rustc_span::source_map::{FileLoader, FileName};
44 use rustc_span::symbol::sym;
48 use std::default::Default;
50 use std::ffi::OsString;
52 use std::io::{self, Read, Write};
54 use std::panic::{self, catch_unwind};
55 use std::path::PathBuf;
56 use std::process::{self, Command, Stdio};
58 use std::time::Instant;
63 /// Exit status code used for successful compilation and help output.
64 pub const EXIT_SUCCESS: i32 = 0;
66 /// Exit status code used for compilation failures and invalid flags.
67 pub const EXIT_FAILURE: i32 = 1;
69 const BUG_REPORT_URL: &str = "https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.\
72 const ICE_REPORT_COMPILER_FLAGS: &[&str] = &["Z", "C", "crate-type"];
74 const ICE_REPORT_COMPILER_FLAGS_EXCLUDE: &[&str] = &["metadata", "extra-filename"];
76 const ICE_REPORT_COMPILER_FLAGS_STRIP_VALUE: &[&str] = &["incremental"];
78 pub fn abort_on_err<T>(result: Result<T, ErrorReported>, sess: &Session) -> T {
81 sess.abort_if_errors();
82 panic!("error reported but abort_if_errors didn't abort???");
89 /// Called before creating the compiler instance
90 fn config(&mut self, _config: &mut interface::Config) {}
91 /// Called after parsing. Return value instructs the compiler whether to
92 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
93 fn after_parsing<'tcx>(
95 _compiler: &interface::Compiler,
96 _queries: &'tcx Queries<'tcx>,
100 /// Called after expansion. Return value instructs the compiler whether to
101 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
102 fn after_expansion<'tcx>(
104 _compiler: &interface::Compiler,
105 _queries: &'tcx Queries<'tcx>,
107 Compilation::Continue
109 /// Called after analysis. Return value instructs the compiler whether to
110 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
111 fn after_analysis<'tcx>(
113 _compiler: &interface::Compiler,
114 _queries: &'tcx Queries<'tcx>,
116 Compilation::Continue
121 pub struct TimePassesCallbacks {
125 impl Callbacks for TimePassesCallbacks {
126 fn config(&mut self, config: &mut interface::Config) {
127 // If a --prints=... option has been given, we don't print the "total"
128 // time because it will mess up the --prints output. See #64339.
129 self.time_passes = config.opts.prints.is_empty()
130 && (config.opts.debugging_opts.time_passes || config.opts.debugging_opts.time);
134 pub fn diagnostics_registry() -> Registry {
135 Registry::new(&rustc_error_codes::DIAGNOSTICS)
138 // Parse args and run the compiler. This is the primary entry point for rustc.
139 // See comments on CompilerCalls below for details about the callbacks argument.
140 // The FileLoader provides a way to load files from sources other than the file system.
143 callbacks: &mut (dyn Callbacks + Send),
144 file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
145 emitter: Option<Box<dyn Write + Send>>,
146 ) -> interface::Result<()> {
147 let mut args = Vec::new();
149 match args::arg_expand(arg.clone()) {
150 Ok(arg) => args.extend(arg),
151 Err(err) => early_error(
152 ErrorOutputType::default(),
153 &format!("Failed to load argument file: {}", err),
157 let diagnostic_output =
158 emitter.map(|emitter| DiagnosticOutput::Raw(emitter)).unwrap_or(DiagnosticOutput::Default);
159 let matches = match handle_options(&args) {
160 Some(matches) => matches,
161 None => return Ok(()),
164 let sopts = config::build_session_options(&matches);
165 let cfg = interface::parse_cfgspecs(matches.opt_strs("cfg"));
167 let mut dummy_config = |sopts, cfg, diagnostic_output| {
168 let mut config = interface::Config {
171 input: Input::File(PathBuf::new()),
179 lint_caps: Default::default(),
180 register_lints: None,
181 override_queries: None,
182 registry: diagnostics_registry(),
184 callbacks.config(&mut config);
188 if let Some(ref code) = matches.opt_str("explain") {
189 handle_explain(diagnostics_registry(), code, sopts.error_format);
193 let (odir, ofile) = make_output(&matches);
194 let (input, input_file_path, input_err) = match make_input(&matches.free) {
196 None => match matches.free.len() {
198 let config = dummy_config(sopts, cfg, diagnostic_output);
199 interface::run_compiler(config, |compiler| {
200 let sopts = &compiler.session().opts;
201 if sopts.describe_lints {
202 let lint_store = rustc_lint::new_lint_store(
203 sopts.debugging_opts.no_interleave_lints,
204 compiler.session().unstable_options(),
206 describe_lints(compiler.session(), &lint_store, false);
209 let should_stop = RustcDefaultCalls::print_crate_info(
210 &***compiler.codegen_backend(),
217 if should_stop == Compilation::Stop {
220 early_error(sopts.error_format, "no input filename given")
224 1 => panic!("make_input should have provided valid inputs"),
228 "multiple input filenames provided (first two filenames are `{}` and `{}`)",
229 matches.free[0], matches.free[1],
235 if let Some(err) = input_err {
236 // Immediately stop compilation if there was an issue reading
237 // the input (for example if the input stream is not UTF-8).
238 interface::run_compiler(dummy_config(sopts, cfg, diagnostic_output), |compiler| {
239 compiler.session().err(&err.to_string());
241 return Err(ErrorReported);
244 let mut config = interface::Config {
248 input_path: input_file_path,
255 lint_caps: Default::default(),
256 register_lints: None,
257 override_queries: None,
258 registry: diagnostics_registry(),
261 callbacks.config(&mut config);
263 interface::run_compiler(config, |compiler| {
264 let sess = compiler.session();
265 let should_stop = RustcDefaultCalls::print_crate_info(
266 &***compiler.codegen_backend(),
268 Some(compiler.input()),
269 compiler.output_dir(),
270 compiler.output_file(),
273 RustcDefaultCalls::list_metadata(
275 &*compiler.codegen_backend().metadata_loader(),
280 .and_then(|| RustcDefaultCalls::try_process_rlink(sess, compiler));
282 if should_stop == Compilation::Stop {
283 return sess.compile_status();
286 let linker = compiler.enter(|queries| {
287 let early_exit = || sess.compile_status().map(|_| None);
290 if let Some(ppm) = &sess.opts.pretty {
291 if ppm.needs_ast_map() {
292 queries.global_ctxt()?.peek_mut().enter(|tcx| {
293 let expanded_crate = queries.expansion()?.take().0;
294 pretty::print_after_hir_lowering(
299 compiler.output_file().as_ref().map(|p| &**p),
304 let krate = queries.parse()?.take();
305 pretty::print_after_parsing(
310 compiler.output_file().as_ref().map(|p| &**p),
316 if callbacks.after_parsing(compiler, queries) == Compilation::Stop {
320 if sess.opts.debugging_opts.parse_only
321 || sess.opts.debugging_opts.show_span.is_some()
322 || sess.opts.debugging_opts.ast_json_noexpand
328 let (_, lint_store) = &*queries.register_plugins()?.peek();
330 // Lint plugins are registered; now we can process command line flags.
331 if sess.opts.describe_lints {
332 describe_lints(&sess, &lint_store, true);
337 queries.expansion()?;
338 if callbacks.after_expansion(compiler, queries) == Compilation::Stop {
342 queries.prepare_outputs()?;
344 if sess.opts.output_types.contains_key(&OutputType::DepInfo)
345 && sess.opts.output_types.len() == 1
350 queries.global_ctxt()?;
352 if sess.opts.debugging_opts.no_analysis || sess.opts.debugging_opts.ast_json {
356 if sess.opts.debugging_opts.save_analysis {
357 let expanded_crate = &queries.expansion()?.peek().0;
358 let crate_name = queries.crate_name()?.peek().clone();
359 queries.global_ctxt()?.peek_mut().enter(|tcx| {
360 let result = tcx.analysis(LOCAL_CRATE);
362 sess.time("save_analysis", || {
370 compiler.output_dir().as_ref().map(|p| &**p),
377 // AST will be dropped *after* the `after_analysis` callback
378 // (needed by the RLS)
381 // Drop AST after creating GlobalCtxt to free memory
382 let _timer = sess.prof.generic_activity("drop_ast");
383 mem::drop(queries.expansion()?.take());
386 queries.global_ctxt()?.peek_mut().enter(|tcx| tcx.analysis(LOCAL_CRATE))?;
388 if callbacks.after_analysis(compiler, queries) == Compilation::Stop {
392 if sess.opts.debugging_opts.save_analysis {
393 mem::drop(queries.expansion()?.take());
396 queries.ongoing_codegen()?;
398 if sess.opts.debugging_opts.print_type_sizes {
399 sess.code_stats.print_type_sizes();
402 let linker = queries.linker()?;
406 if let Some(linker) = linker {
407 let _timer = sess.timer("link");
411 if sess.opts.debugging_opts.perf_stats {
412 sess.print_perf_stats();
415 if sess.print_fuel_crate.is_some() {
417 "Fuel used by {}: {}",
418 sess.print_fuel_crate.as_ref().unwrap(),
419 sess.print_fuel.load(SeqCst)
428 pub fn set_sigpipe_handler() {
430 // Set the SIGPIPE signal handler, so that an EPIPE
431 // will cause rustc to terminate, as expected.
432 assert_ne!(libc::signal(libc::SIGPIPE, libc::SIG_DFL), libc::SIG_ERR);
437 pub fn set_sigpipe_handler() {}
439 // Extract output directory and file from matches.
440 fn make_output(matches: &getopts::Matches) -> (Option<PathBuf>, Option<PathBuf>) {
441 let odir = matches.opt_str("out-dir").map(|o| PathBuf::from(&o));
442 let ofile = matches.opt_str("o").map(|o| PathBuf::from(&o));
446 // Extract input (string or file and optional path) from matches.
447 fn make_input(free_matches: &[String]) -> Option<(Input, Option<PathBuf>, Option<io::Error>)> {
448 if free_matches.len() == 1 {
449 let ifile = &free_matches[0];
451 let mut src = String::new();
452 let err = if io::stdin().read_to_string(&mut src).is_err() {
454 io::ErrorKind::InvalidData,
455 "couldn't read from stdin, as it did not contain valid UTF-8",
460 if let Ok(path) = env::var("UNSTABLE_RUSTDOC_TEST_PATH") {
461 let line = env::var("UNSTABLE_RUSTDOC_TEST_LINE").expect(
462 "when UNSTABLE_RUSTDOC_TEST_PATH is set \
463 UNSTABLE_RUSTDOC_TEST_LINE also needs to be set",
465 let line = isize::from_str_radix(&line, 10)
466 .expect("UNSTABLE_RUSTDOC_TEST_LINE needs to be an number");
467 let file_name = FileName::doc_test_source_code(PathBuf::from(path), line);
468 return Some((Input::Str { name: file_name, input: src }, None, err));
470 Some((Input::Str { name: FileName::anon_source_code(&src), input: src }, None, err))
472 Some((Input::File(PathBuf::from(ifile)), Some(PathBuf::from(ifile)), None))
479 // Whether to stop or continue compilation.
480 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
481 pub enum Compilation {
487 pub fn and_then<F: FnOnce() -> Compilation>(self, next: F) -> Compilation {
489 Compilation::Stop => Compilation::Stop,
490 Compilation::Continue => next(),
495 /// CompilerCalls instance for a regular rustc build.
496 #[derive(Copy, Clone)]
497 pub struct RustcDefaultCalls;
499 // FIXME remove these and use winapi 0.3 instead
500 // Duplicates: bootstrap/compile.rs, librustc_errors/emitter.rs
502 fn stdout_isatty() -> bool {
503 unsafe { libc::isatty(libc::STDOUT_FILENO) != 0 }
507 fn stdout_isatty() -> bool {
508 use winapi::um::consoleapi::GetConsoleMode;
509 use winapi::um::processenv::GetStdHandle;
510 use winapi::um::winbase::STD_OUTPUT_HANDLE;
513 let handle = GetStdHandle(STD_OUTPUT_HANDLE);
515 GetConsoleMode(handle, &mut out) != 0
519 fn handle_explain(registry: Registry, code: &str, output: ErrorOutputType) {
521 if code.starts_with('E') { code.to_string() } else { format!("E{0:0>4}", code) };
522 match registry.try_find_description(&normalised) {
523 Ok(Some(description)) => {
524 let mut is_in_code_block = false;
525 let mut text = String::new();
526 // Slice off the leading newline and print.
527 for line in description.lines() {
529 line.find(|c: char| !c.is_whitespace()).unwrap_or_else(|| line.len());
530 let dedented_line = &line[indent_level..];
531 if dedented_line.starts_with("```") {
532 is_in_code_block = !is_in_code_block;
533 text.push_str(&line[..(indent_level + 3)]);
534 } else if is_in_code_block && dedented_line.starts_with("# ") {
542 show_content_with_pager(&text);
548 early_error(output, &format!("no extended information for {}", code));
550 Err(InvalidErrorCode) => {
551 early_error(output, &format!("{} is not a valid error code", code));
556 fn show_content_with_pager(content: &String) {
557 let pager_name = env::var_os("PAGER").unwrap_or_else(|| {
558 if cfg!(windows) { OsString::from("more.com") } else { OsString::from("less") }
561 let mut fallback_to_println = false;
563 match Command::new(pager_name).stdin(Stdio::piped()).spawn() {
565 if let Some(pipe) = pager.stdin.as_mut() {
566 if pipe.write_all(content.as_bytes()).is_err() {
567 fallback_to_println = true;
571 if pager.wait().is_err() {
572 fallback_to_println = true;
576 fallback_to_println = true;
580 // If pager fails for whatever reason, we should still print the content
581 // to standard output
582 if fallback_to_println {
583 print!("{}", content);
587 impl RustcDefaultCalls {
588 fn process_rlink(sess: &Session, compiler: &interface::Compiler) -> Result<(), ErrorReported> {
589 if let Input::File(file) = compiler.input() {
590 // FIXME: #![crate_type] and #![crate_name] support not implemented yet
592 sess.crate_types.set(collect_crate_types(sess, &attrs));
593 let outputs = compiler.build_output_filenames(&sess, &attrs);
594 let rlink_data = fs::read_to_string(file).unwrap_or_else(|err| {
595 sess.fatal(&format!("failed to read rlink file: {}", err));
597 let codegen_results: CodegenResults = json::decode(&rlink_data).unwrap_or_else(|err| {
598 sess.fatal(&format!("failed to decode rlink: {}", err));
600 compiler.codegen_backend().link(&sess, Box::new(codegen_results), &outputs)
602 sess.fatal("rlink must be a file")
606 pub fn try_process_rlink(sess: &Session, compiler: &interface::Compiler) -> Compilation {
607 if sess.opts.debugging_opts.link_only {
608 let result = RustcDefaultCalls::process_rlink(sess, compiler);
609 abort_on_err(result, sess);
612 Compilation::Continue
616 pub fn list_metadata(
618 metadata_loader: &dyn MetadataLoader,
619 matches: &getopts::Matches,
622 let r = matches.opt_strs("Z");
623 if r.iter().any(|s| *s == "ls") {
625 &Input::File(ref ifile) => {
626 let path = &(*ifile);
627 let mut v = Vec::new();
628 locator::list_file_metadata(&sess.target.target, path, metadata_loader, &mut v)
630 println!("{}", String::from_utf8(v).unwrap());
632 &Input::Str { .. } => {
633 early_error(ErrorOutputType::default(), "cannot list metadata for stdin");
636 return Compilation::Stop;
639 Compilation::Continue
643 codegen_backend: &dyn CodegenBackend,
645 input: Option<&Input>,
646 odir: &Option<PathBuf>,
647 ofile: &Option<PathBuf>,
649 use rustc_session::config::PrintRequest::*;
650 // PrintRequest::NativeStaticLibs is special - printed during linking
651 // (empty iterator returns true)
652 if sess.opts.prints.iter().all(|&p| p == PrintRequest::NativeStaticLibs) {
653 return Compilation::Continue;
656 let attrs = match input {
659 let result = parse_crate_attrs(sess, input);
661 Ok(attrs) => Some(attrs),
662 Err(mut parse_error) => {
664 return Compilation::Stop;
669 for req in &sess.opts.prints {
672 let mut targets = rustc_target::spec::get_targets().collect::<Vec<String>>();
674 println!("{}", targets.join("\n"));
676 Sysroot => println!("{}", sess.sysroot.display()),
677 TargetLibdir => println!(
679 sess.target_tlib_path.as_ref().unwrap_or(&sess.host_tlib_path).dir.display()
681 TargetSpec => println!("{}", sess.target.target.to_json().pretty()),
682 FileNames | CrateName => {
683 let input = input.unwrap_or_else(|| {
684 early_error(ErrorOutputType::default(), "no input file provided")
686 let attrs = attrs.as_ref().unwrap();
687 let t_outputs = rustc_interface::util::build_output_filenames(
688 input, odir, ofile, attrs, sess,
690 let id = rustc_session::output::find_crate_name(Some(sess), attrs, input);
691 if *req == PrintRequest::CrateName {
695 let crate_types = collect_crate_types(sess, attrs);
696 for &style in &crate_types {
698 rustc_session::output::filename_for_input(sess, style, &id, &t_outputs);
699 println!("{}", fname.file_name().unwrap().to_string_lossy());
703 let allow_unstable_cfg =
704 UnstableFeatures::from_environment().is_nightly_build();
710 .filter_map(|&(name, ref value)| {
711 // Note that crt-static is a specially recognized cfg
712 // directive that's printed out here as part of
713 // rust-lang/rust#37406, but in general the
714 // `target_feature` cfg is gated under
715 // rust-lang/rust#29717. For now this is just
716 // specifically allowing the crt-static cfg and that's
717 // it, this is intended to get into Cargo and then go
718 // through to build scripts.
719 let value = value.as_ref().map(|s| s.as_str());
720 let value = value.as_ref().map(|s| s.as_ref());
721 if (name != sym::target_feature || value != Some("crt-static"))
722 && !allow_unstable_cfg
723 && find_gated_cfg(|cfg_sym| cfg_sym == name).is_some()
728 if let Some(value) = value {
729 Some(format!("{}=\"{}\"", name, value))
731 Some(name.to_string())
734 .collect::<Vec<String>>();
741 RelocationModels | CodeModels | TlsModels | TargetCPUs | TargetFeatures => {
742 codegen_backend.print(*req, sess);
744 // Any output here interferes with Cargo's parsing of other printed output
745 PrintRequest::NativeStaticLibs => {}
752 /// Returns a version string such as "0.12.0-dev".
753 fn release_str() -> Option<&'static str> {
754 option_env!("CFG_RELEASE")
757 /// Returns the full SHA1 hash of HEAD of the Git repo from which rustc was built.
758 fn commit_hash_str() -> Option<&'static str> {
759 option_env!("CFG_VER_HASH")
762 /// Returns the "commit date" of HEAD of the Git repo from which rustc was built as a static string.
763 fn commit_date_str() -> Option<&'static str> {
764 option_env!("CFG_VER_DATE")
767 /// Prints version information
768 pub fn version(binary: &str, matches: &getopts::Matches) {
769 let verbose = matches.opt_present("verbose");
771 println!("{} {}", binary, option_env!("CFG_VERSION").unwrap_or("unknown version"));
774 fn unw(x: Option<&str>) -> &str {
775 x.unwrap_or("unknown")
777 println!("binary: {}", binary);
778 println!("commit-hash: {}", unw(commit_hash_str()));
779 println!("commit-date: {}", unw(commit_date_str()));
780 println!("host: {}", config::host_triple());
781 println!("release: {}", unw(release_str()));
782 get_builtin_codegen_backend("llvm")().print_version();
786 fn usage(verbose: bool, include_unstable_options: bool) {
787 let groups = if verbose { config::rustc_optgroups() } else { config::rustc_short_optgroups() };
788 let mut options = getopts::Options::new();
789 for option in groups.iter().filter(|x| include_unstable_options || x.is_stable()) {
790 (option.apply)(&mut options);
792 let message = "Usage: rustc [OPTIONS] INPUT";
793 let nightly_help = if nightly_options::is_nightly_build() {
794 "\n -Z help Print unstable compiler options"
798 let verbose_help = if verbose {
801 "\n --help -v Print the full set of options rustc accepts"
803 let at_path = if verbose && nightly_options::is_nightly_build() {
804 " @path Read newline separated options from `path`\n"
809 "{options}{at_path}\nAdditional help:
810 -C help Print codegen options
812 Print 'lint' options and default settings{nightly}{verbose}\n",
813 options = options.usage(message),
815 nightly = nightly_help,
816 verbose = verbose_help
820 fn print_wall_help() {
823 The flag `-Wall` does not exist in `rustc`. Most useful lints are enabled by
824 default. Use `rustc -W help` to see all available lints. It's more common to put
825 warning settings in the crate root using `#![warn(LINT_NAME)]` instead of using
826 the command line flag directly.
831 fn describe_lints(sess: &Session, lint_store: &LintStore, loaded_plugins: bool) {
834 Available lint options:
835 -W <foo> Warn about <foo>
839 -F <foo> Forbid <foo> \
840 (deny <foo> and all attempts to override)
845 fn sort_lints(sess: &Session, mut lints: Vec<&'static Lint>) -> Vec<&'static Lint> {
846 // The sort doesn't case-fold but it's doubtful we care.
847 lints.sort_by_cached_key(|x: &&Lint| (x.default_level(sess.edition()), x.name));
852 lints: Vec<(&'static str, Vec<LintId>, bool)>,
853 ) -> Vec<(&'static str, Vec<LintId>)> {
854 let mut lints: Vec<_> = lints.into_iter().map(|(x, y, _)| (x, y)).collect();
855 lints.sort_by_key(|l| l.0);
859 let (plugin, builtin): (Vec<_>, _) =
860 lint_store.get_lints().iter().cloned().partition(|&lint| lint.is_plugin);
861 let plugin = sort_lints(sess, plugin);
862 let builtin = sort_lints(sess, builtin);
864 let (plugin_groups, builtin_groups): (Vec<_>, _) =
865 lint_store.get_lint_groups().iter().cloned().partition(|&(.., p)| p);
866 let plugin_groups = sort_lint_groups(plugin_groups);
867 let builtin_groups = sort_lint_groups(builtin_groups);
870 plugin.iter().chain(&builtin).map(|&s| s.name.chars().count()).max().unwrap_or(0);
871 let padded = |x: &str| {
872 let mut s = " ".repeat(max_name_len - x.chars().count());
877 println!("Lint checks provided by rustc:\n");
878 println!(" {} {:7.7} {}", padded("name"), "default", "meaning");
879 println!(" {} {:7.7} {}", padded("----"), "-------", "-------");
881 let print_lints = |lints: Vec<&Lint>| {
883 let name = lint.name_lower().replace("_", "-");
884 println!(" {} {:7.7} {}", padded(&name), lint.default_level.as_str(), lint.desc);
889 print_lints(builtin);
891 let max_name_len = max(
895 .chain(&builtin_groups)
896 .map(|&(s, _)| s.chars().count())
901 let padded = |x: &str| {
902 let mut s = " ".repeat(max_name_len - x.chars().count());
907 println!("Lint groups provided by rustc:\n");
908 println!(" {} {}", padded("name"), "sub-lints");
909 println!(" {} {}", padded("----"), "---------");
910 println!(" {} {}", padded("warnings"), "all lints that are set to issue warnings");
912 let print_lint_groups = |lints: Vec<(&'static str, Vec<LintId>)>| {
913 for (name, to) in lints {
914 let name = name.to_lowercase().replace("_", "-");
917 .map(|x| x.to_string().replace("_", "-"))
918 .collect::<Vec<String>>()
920 println!(" {} {}", padded(&name), desc);
925 print_lint_groups(builtin_groups);
927 match (loaded_plugins, plugin.len(), plugin_groups.len()) {
928 (false, 0, _) | (false, _, 0) => {
930 "Compiler plugins can provide additional lints and lint groups. To see a \
931 listing of these, re-run `rustc -W help` with a crate filename."
934 (false, ..) => panic!("didn't load lint plugins but got them anyway!"),
935 (true, 0, 0) => println!("This crate does not load any lint plugins or lint groups."),
938 println!("Lint checks provided by plugins loaded by this crate:\n");
942 println!("Lint groups provided by plugins loaded by this crate:\n");
943 print_lint_groups(plugin_groups);
949 fn describe_debug_flags() {
950 println!("\nAvailable options:\n");
951 print_flag_list("-Z", config::DB_OPTIONS);
954 fn describe_codegen_flags() {
955 println!("\nAvailable codegen options:\n");
956 print_flag_list("-C", config::CG_OPTIONS);
959 fn print_flag_list<T>(
961 flag_list: &[(&'static str, T, Option<&'static str>, &'static str)],
963 let max_len = flag_list
965 .map(|&(name, _, opt_type_desc, _)| {
966 let extra_len = match opt_type_desc {
970 name.chars().count() + extra_len
975 for &(name, _, opt_type_desc, desc) in flag_list {
976 let (width, extra) = match opt_type_desc {
977 Some(..) => (max_len - 4, "=val"),
978 None => (max_len, ""),
981 " {} {:>width$}{} -- {}",
983 name.replace("_", "-"),
991 /// Process command line options. Emits messages as appropriate. If compilation
992 /// should continue, returns a getopts::Matches object parsed from args,
993 /// otherwise returns `None`.
995 /// The compiler's handling of options is a little complicated as it ties into
996 /// our stability story. The current intention of each compiler option is to
997 /// have one of two modes:
999 /// 1. An option is stable and can be used everywhere.
1000 /// 2. An option is unstable, and can only be used on nightly.
1002 /// Like unstable library and language features, however, unstable options have
1003 /// always required a form of "opt in" to indicate that you're using them. This
1004 /// provides the easy ability to scan a code base to check to see if anything
1005 /// unstable is being used. Currently, this "opt in" is the `-Z` "zed" flag.
1007 /// All options behind `-Z` are considered unstable by default. Other top-level
1008 /// options can also be considered unstable, and they were unlocked through the
1009 /// `-Z unstable-options` flag. Note that `-Z` remains to be the root of
1010 /// instability in both cases, though.
1012 /// So with all that in mind, the comments below have some more detail about the
1013 /// contortions done here to get things to work out correctly.
1014 pub fn handle_options(args: &[String]) -> Option<getopts::Matches> {
1015 // Throw away the first argument, the name of the binary
1016 let args = &args[1..];
1018 if args.is_empty() {
1019 // user did not write `-v` nor `-Z unstable-options`, so do not
1020 // include that extra information.
1021 usage(false, false);
1025 // Parse with *all* options defined in the compiler, we don't worry about
1026 // option stability here we just want to parse as much as possible.
1027 let mut options = getopts::Options::new();
1028 for option in config::rustc_optgroups() {
1029 (option.apply)(&mut options);
1031 let matches = options
1033 .unwrap_or_else(|f| early_error(ErrorOutputType::default(), &f.to_string()));
1035 // For all options we just parsed, we check a few aspects:
1037 // * If the option is stable, we're all good
1038 // * If the option wasn't passed, we're all good
1039 // * If `-Z unstable-options` wasn't passed (and we're not a -Z option
1040 // ourselves), then we require the `-Z unstable-options` flag to unlock
1041 // this option that was passed.
1042 // * If we're a nightly compiler, then unstable options are now unlocked, so
1043 // we're good to go.
1044 // * Otherwise, if we're an unstable option then we generate an error
1045 // (unstable option being used on stable)
1046 nightly_options::check_nightly_options(&matches, &config::rustc_optgroups());
1048 if matches.opt_present("h") || matches.opt_present("help") {
1049 // Only show unstable options in --help if we accept unstable options.
1050 usage(matches.opt_present("verbose"), nightly_options::is_unstable_enabled(&matches));
1054 // Handle the special case of -Wall.
1055 let wall = matches.opt_strs("W");
1056 if wall.iter().any(|x| *x == "all") {
1061 // Don't handle -W help here, because we might first load plugins.
1062 let r = matches.opt_strs("Z");
1063 if r.iter().any(|x| *x == "help") {
1064 describe_debug_flags();
1068 let cg_flags = matches.opt_strs("C");
1070 if cg_flags.iter().any(|x| *x == "help") {
1071 describe_codegen_flags();
1075 if cg_flags.iter().any(|x| *x == "no-stack-check") {
1077 ErrorOutputType::default(),
1078 "the --no-stack-check flag is deprecated and does nothing",
1082 if cg_flags.iter().any(|x| *x == "passes=list") {
1083 get_builtin_codegen_backend("llvm")().print_passes();
1087 if matches.opt_present("version") {
1088 version("rustc", &matches);
1095 fn parse_crate_attrs<'a>(sess: &'a Session, input: &Input) -> PResult<'a, Vec<ast::Attribute>> {
1097 Input::File(ifile) => rustc_parse::parse_crate_attrs_from_file(ifile, &sess.parse_sess),
1098 Input::Str { name, input } => rustc_parse::parse_crate_attrs_from_source_str(
1106 /// Gets a list of extra command-line flags provided by the user, as strings.
1108 /// This function is used during ICEs to show more information useful for
1109 /// debugging, since some ICEs only happens with non-default compiler flags
1110 /// (and the users don't always report them).
1111 fn extra_compiler_flags() -> Option<(Vec<String>, bool)> {
1112 let args = env::args_os().map(|arg| arg.to_string_lossy().to_string()).collect::<Vec<_>>();
1114 // Avoid printing help because of empty args. This can suggest the compiler
1115 // itself is not the program root (consider RLS).
1120 let matches = handle_options(&args)?;
1121 let mut result = Vec::new();
1122 let mut excluded_cargo_defaults = false;
1123 for flag in ICE_REPORT_COMPILER_FLAGS {
1124 let prefix = if flag.len() == 1 { "-" } else { "--" };
1126 for content in &matches.opt_strs(flag) {
1127 // Split always returns the first element
1128 let name = if let Some(first) = content.split('=').next() { first } else { &content };
1131 if ICE_REPORT_COMPILER_FLAGS_STRIP_VALUE.contains(&name) { name } else { content };
1133 if !ICE_REPORT_COMPILER_FLAGS_EXCLUDE.contains(&name) {
1134 result.push(format!("{}{} {}", prefix, flag, content));
1136 excluded_cargo_defaults = true;
1141 if !result.is_empty() { Some((result, excluded_cargo_defaults)) } else { None }
1144 /// Runs a closure and catches unwinds triggered by fatal errors.
1146 /// The compiler currently unwinds with a special sentinel value to abort
1147 /// compilation on fatal errors. This function catches that sentinel and turns
1148 /// the panic into a `Result` instead.
1149 pub fn catch_fatal_errors<F: FnOnce() -> R, R>(f: F) -> Result<R, ErrorReported> {
1150 catch_unwind(panic::AssertUnwindSafe(f)).map_err(|value| {
1151 if value.is::<rustc_errors::FatalErrorMarker>() {
1154 panic::resume_unwind(value);
1160 static ref DEFAULT_HOOK: Box<dyn Fn(&panic::PanicInfo<'_>) + Sync + Send + 'static> = {
1161 let hook = panic::take_hook();
1162 panic::set_hook(Box::new(|info| report_ice(info, BUG_REPORT_URL)));
1167 /// Prints the ICE message, including backtrace and query stack.
1169 /// The message will point the user at `bug_report_url` to report the ICE.
1171 /// When `install_ice_hook` is called, this function will be called as the panic
1173 pub fn report_ice(info: &panic::PanicInfo<'_>, bug_report_url: &str) {
1174 // Invoke the default handler, which prints the actual panic message and optionally a backtrace
1175 (*DEFAULT_HOOK)(info);
1177 // Separate the output with an empty line
1180 let emitter = Box::new(rustc_errors::emitter::EmitterWriter::stderr(
1181 rustc_errors::ColorConfig::Auto,
1188 let handler = rustc_errors::Handler::with_emitter(true, None, emitter);
1190 // a .span_bug or .bug call has already printed what
1191 // it wants to print.
1192 if !info.payload().is::<rustc_errors::ExplicitBug>() {
1193 let d = rustc_errors::Diagnostic::new(rustc_errors::Level::Bug, "unexpected panic");
1194 handler.emit_diagnostic(&d);
1197 let mut xs: Vec<Cow<'static, str>> = vec![
1198 "the compiler unexpectedly panicked. this is a bug.".into(),
1199 format!("we would appreciate a bug report: {}", bug_report_url).into(),
1201 "rustc {} running on {}",
1202 option_env!("CFG_VERSION").unwrap_or("unknown_version"),
1203 config::host_triple()
1208 if let Some((flags, excluded_cargo_defaults)) = extra_compiler_flags() {
1209 xs.push(format!("compiler flags: {}", flags.join(" ")).into());
1211 if excluded_cargo_defaults {
1212 xs.push("some of the compiler flags provided by cargo are hidden".into());
1217 handler.note_without_error(¬e);
1220 // If backtraces are enabled, also print the query stack
1221 let backtrace = env::var_os("RUST_BACKTRACE").map(|x| &x != "0").unwrap_or(false);
1224 TyCtxt::try_print_query_stack(&handler);
1229 if env::var("RUSTC_BREAK_ON_ICE").is_ok() {
1230 // Trigger a debugger if we crashed during bootstrap
1231 winapi::um::debugapi::DebugBreak();
1236 /// Installs a panic hook that will print the ICE message on unexpected panics.
1238 /// A custom rustc driver can skip calling this to set up a custom ICE hook.
1239 pub fn install_ice_hook() {
1240 lazy_static::initialize(&DEFAULT_HOOK);
1243 /// This allows tools to enable rust logging without having to magically match rustc's
1244 /// log crate version
1245 pub fn init_rustc_env_logger() {
1246 env_logger::init_from_env("RUSTC_LOG");
1250 let start = Instant::now();
1251 init_rustc_env_logger();
1252 let mut callbacks = TimePassesCallbacks::default();
1254 let result = catch_fatal_errors(|| {
1255 let args = env::args_os()
1258 arg.into_string().unwrap_or_else(|arg| {
1260 ErrorOutputType::default(),
1261 &format!("Argument {} is not valid Unicode: {:?}", i, arg),
1265 .collect::<Vec<_>>();
1266 run_compiler(&args, &mut callbacks, None, None)
1268 .and_then(|result| result);
1269 let exit_code = match result {
1270 Ok(_) => EXIT_SUCCESS,
1271 Err(_) => EXIT_FAILURE,
1273 // The extra `\t` is necessary to align this label with the others.
1274 print_time_passes_entry(callbacks.time_passes, "\ttotal", start.elapsed());
1275 process::exit(exit_code);