5 //! This API is completely unstable and subject to change.
7 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/")]
9 #![cfg_attr(bootstrap, feature(track_caller))]
10 #![recursion_limit = "256"]
15 extern crate lazy_static;
17 pub extern crate rustc_plugin_impl as plugin;
20 use rustc_codegen_ssa::{traits::CodegenBackend, CodegenResults};
21 use rustc_data_structures::profiling::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, UnstableFeatures};
26 use rustc_hir::def_id::LOCAL_CRATE;
27 use rustc_interface::util::{collect_crate_types, get_builtin_codegen_backend};
28 use rustc_interface::{interface, Queries};
29 use rustc_lint::LintStore;
30 use rustc_metadata::locator;
31 use rustc_middle::middle::cstore::MetadataLoader;
32 use rustc_middle::ty::TyCtxt;
33 use rustc_save_analysis as save;
34 use rustc_save_analysis::DumpHandler;
35 use rustc_serialize::json::{self, ToJson};
36 use rustc_session::config::nightly_options;
37 use rustc_session::config::{ErrorOutputType, Input, OutputType, PrintRequest};
38 use rustc_session::getopts;
39 use rustc_session::lint::{Lint, LintId};
40 use rustc_session::{config, DiagnosticOutput, Session};
41 use rustc_session::{early_error, early_warn};
42 use rustc_span::source_map::{FileLoader, FileName};
43 use rustc_span::symbol::sym;
47 use std::default::Default;
49 use std::ffi::OsString;
51 use std::io::{self, Read, Write};
53 use std::panic::{self, catch_unwind};
54 use std::path::PathBuf;
55 use std::process::{self, Command, Stdio};
57 use std::time::Instant;
62 /// Exit status code used for successful compilation and help output.
63 pub const EXIT_SUCCESS: i32 = 0;
65 /// Exit status code used for compilation failures and invalid flags.
66 pub const EXIT_FAILURE: i32 = 1;
68 const BUG_REPORT_URL: &str = "https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.\
71 const ICE_REPORT_COMPILER_FLAGS: &[&str] = &["Z", "C", "crate-type"];
73 const ICE_REPORT_COMPILER_FLAGS_EXCLUDE: &[&str] = &["metadata", "extra-filename"];
75 const ICE_REPORT_COMPILER_FLAGS_STRIP_VALUE: &[&str] = &["incremental"];
77 pub fn abort_on_err<T>(result: Result<T, ErrorReported>, sess: &Session) -> T {
80 sess.abort_if_errors();
81 panic!("error reported but abort_if_errors didn't abort???");
88 /// Called before creating the compiler instance
89 fn config(&mut self, _config: &mut interface::Config) {}
90 /// Called after parsing. Return value instructs the compiler whether to
91 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
92 fn after_parsing<'tcx>(
94 _compiler: &interface::Compiler,
95 _queries: &'tcx Queries<'tcx>,
99 /// Called after expansion. Return value instructs the compiler whether to
100 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
101 fn after_expansion<'tcx>(
103 _compiler: &interface::Compiler,
104 _queries: &'tcx Queries<'tcx>,
106 Compilation::Continue
108 /// Called after analysis. Return value instructs the compiler whether to
109 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
110 fn after_analysis<'tcx>(
112 _compiler: &interface::Compiler,
113 _queries: &'tcx Queries<'tcx>,
115 Compilation::Continue
120 pub struct TimePassesCallbacks {
124 impl Callbacks for TimePassesCallbacks {
125 fn config(&mut self, config: &mut interface::Config) {
126 // If a --prints=... option has been given, we don't print the "total"
127 // time because it will mess up the --prints output. See #64339.
128 self.time_passes = config.opts.prints.is_empty()
129 && (config.opts.debugging_opts.time_passes || config.opts.debugging_opts.time);
133 pub fn diagnostics_registry() -> Registry {
134 Registry::new(&rustc_error_codes::DIAGNOSTICS)
137 // Parse args and run the compiler. This is the primary entry point for rustc.
138 // The FileLoader provides a way to load files from sources other than the file system.
141 callbacks: &mut (dyn Callbacks + Send),
142 file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
143 emitter: Option<Box<dyn Write + Send>>,
144 ) -> interface::Result<()> {
145 let mut args = Vec::new();
147 match args::arg_expand(arg.clone()) {
148 Ok(arg) => args.extend(arg),
149 Err(err) => early_error(
150 ErrorOutputType::default(),
151 &format!("Failed to load argument file: {}", err),
155 let diagnostic_output =
156 emitter.map(|emitter| DiagnosticOutput::Raw(emitter)).unwrap_or(DiagnosticOutput::Default);
157 let matches = match handle_options(&args) {
158 Some(matches) => matches,
159 None => return Ok(()),
162 let sopts = config::build_session_options(&matches);
163 let cfg = interface::parse_cfgspecs(matches.opt_strs("cfg"));
165 let mut dummy_config = |sopts, cfg, diagnostic_output| {
166 let mut config = interface::Config {
169 input: Input::File(PathBuf::new()),
177 lint_caps: Default::default(),
178 register_lints: None,
179 override_queries: None,
180 registry: diagnostics_registry(),
182 callbacks.config(&mut config);
186 if let Some(ref code) = matches.opt_str("explain") {
187 handle_explain(diagnostics_registry(), code, sopts.error_format);
191 let (odir, ofile) = make_output(&matches);
192 let (input, input_file_path, input_err) = match make_input(&matches.free) {
194 None => match matches.free.len() {
196 let config = dummy_config(sopts, cfg, diagnostic_output);
197 interface::run_compiler(config, |compiler| {
198 let sopts = &compiler.session().opts;
199 if sopts.describe_lints {
200 let lint_store = rustc_lint::new_lint_store(
201 sopts.debugging_opts.no_interleave_lints,
202 compiler.session().unstable_options(),
204 describe_lints(compiler.session(), &lint_store, false);
207 let should_stop = RustcDefaultCalls::print_crate_info(
208 &***compiler.codegen_backend(),
215 if should_stop == Compilation::Stop {
218 early_error(sopts.error_format, "no input filename given")
222 1 => panic!("make_input should have provided valid inputs"),
226 "multiple input filenames provided (first two filenames are `{}` and `{}`)",
227 matches.free[0], matches.free[1],
233 if let Some(err) = input_err {
234 // Immediately stop compilation if there was an issue reading
235 // the input (for example if the input stream is not UTF-8).
236 interface::run_compiler(dummy_config(sopts, cfg, diagnostic_output), |compiler| {
237 compiler.session().err(&err.to_string());
239 return Err(ErrorReported);
242 let mut config = interface::Config {
246 input_path: input_file_path,
253 lint_caps: Default::default(),
254 register_lints: None,
255 override_queries: None,
256 registry: diagnostics_registry(),
259 callbacks.config(&mut config);
261 interface::run_compiler(config, |compiler| {
262 let sess = compiler.session();
263 let should_stop = RustcDefaultCalls::print_crate_info(
264 &***compiler.codegen_backend(),
266 Some(compiler.input()),
267 compiler.output_dir(),
268 compiler.output_file(),
271 RustcDefaultCalls::list_metadata(
273 &*compiler.codegen_backend().metadata_loader(),
278 .and_then(|| RustcDefaultCalls::try_process_rlink(sess, compiler));
280 if should_stop == Compilation::Stop {
281 return sess.compile_status();
284 let linker = compiler.enter(|queries| {
285 let early_exit = || sess.compile_status().map(|_| None);
288 if let Some(ppm) = &sess.opts.pretty {
289 if ppm.needs_ast_map() {
290 queries.global_ctxt()?.peek_mut().enter(|tcx| {
291 let expanded_crate = queries.expansion()?.take().0;
292 pretty::print_after_hir_lowering(
297 compiler.output_file().as_ref().map(|p| &**p),
302 let krate = queries.parse()?.take();
303 pretty::print_after_parsing(
308 compiler.output_file().as_ref().map(|p| &**p),
311 trace!("finished pretty-printing");
315 if callbacks.after_parsing(compiler, queries) == Compilation::Stop {
319 if sess.opts.debugging_opts.parse_only
320 || sess.opts.debugging_opts.show_span.is_some()
321 || sess.opts.debugging_opts.ast_json_noexpand
327 let (_, lint_store) = &*queries.register_plugins()?.peek();
329 // Lint plugins are registered; now we can process command line flags.
330 if sess.opts.describe_lints {
331 describe_lints(&sess, &lint_store, true);
336 queries.expansion()?;
337 if callbacks.after_expansion(compiler, queries) == Compilation::Stop {
341 queries.prepare_outputs()?;
343 if sess.opts.output_types.contains_key(&OutputType::DepInfo)
344 && sess.opts.output_types.len() == 1
349 queries.global_ctxt()?;
351 // Drop AST after creating GlobalCtxt to free memory
352 let _timer = sess.prof.generic_activity("drop_ast");
353 mem::drop(queries.expansion()?.take());
355 if sess.opts.debugging_opts.no_analysis || sess.opts.debugging_opts.ast_json {
359 if sess.opts.debugging_opts.save_analysis {
360 let crate_name = queries.crate_name()?.peek().clone();
361 queries.global_ctxt()?.peek_mut().enter(|tcx| {
362 let result = tcx.analysis(LOCAL_CRATE);
364 sess.time("save_analysis", || {
371 compiler.output_dir().as_ref().map(|p| &**p),
381 queries.global_ctxt()?.peek_mut().enter(|tcx| tcx.analysis(LOCAL_CRATE))?;
383 if callbacks.after_analysis(compiler, queries) == Compilation::Stop {
387 queries.ongoing_codegen()?;
389 if sess.opts.debugging_opts.print_type_sizes {
390 sess.code_stats.print_type_sizes();
393 let linker = queries.linker()?;
397 if let Some(linker) = linker {
398 let _timer = sess.timer("link");
402 if sess.opts.debugging_opts.perf_stats {
403 sess.print_perf_stats();
406 if sess.print_fuel_crate.is_some() {
408 "Fuel used by {}: {}",
409 sess.print_fuel_crate.as_ref().unwrap(),
410 sess.print_fuel.load(SeqCst)
419 pub fn set_sigpipe_handler() {
421 // Set the SIGPIPE signal handler, so that an EPIPE
422 // will cause rustc to terminate, as expected.
423 assert_ne!(libc::signal(libc::SIGPIPE, libc::SIG_DFL), libc::SIG_ERR);
428 pub fn set_sigpipe_handler() {}
430 // Extract output directory and file from matches.
431 fn make_output(matches: &getopts::Matches) -> (Option<PathBuf>, Option<PathBuf>) {
432 let odir = matches.opt_str("out-dir").map(|o| PathBuf::from(&o));
433 let ofile = matches.opt_str("o").map(|o| PathBuf::from(&o));
437 // Extract input (string or file and optional path) from matches.
438 fn make_input(free_matches: &[String]) -> Option<(Input, Option<PathBuf>, Option<io::Error>)> {
439 if free_matches.len() == 1 {
440 let ifile = &free_matches[0];
442 let mut src = String::new();
443 let err = if io::stdin().read_to_string(&mut src).is_err() {
445 io::ErrorKind::InvalidData,
446 "couldn't read from stdin, as it did not contain valid UTF-8",
451 if let Ok(path) = env::var("UNSTABLE_RUSTDOC_TEST_PATH") {
452 let line = env::var("UNSTABLE_RUSTDOC_TEST_LINE").expect(
453 "when UNSTABLE_RUSTDOC_TEST_PATH is set \
454 UNSTABLE_RUSTDOC_TEST_LINE also needs to be set",
456 let line = isize::from_str_radix(&line, 10)
457 .expect("UNSTABLE_RUSTDOC_TEST_LINE needs to be an number");
458 let file_name = FileName::doc_test_source_code(PathBuf::from(path), line);
459 return Some((Input::Str { name: file_name, input: src }, None, err));
461 Some((Input::Str { name: FileName::anon_source_code(&src), input: src }, None, err))
463 Some((Input::File(PathBuf::from(ifile)), Some(PathBuf::from(ifile)), None))
470 // Whether to stop or continue compilation.
471 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
472 pub enum Compilation {
478 pub fn and_then<F: FnOnce() -> Compilation>(self, next: F) -> Compilation {
480 Compilation::Stop => Compilation::Stop,
481 Compilation::Continue => next(),
486 /// CompilerCalls instance for a regular rustc build.
487 #[derive(Copy, Clone)]
488 pub struct RustcDefaultCalls;
490 // FIXME remove these and use winapi 0.3 instead
491 // Duplicates: bootstrap/compile.rs, librustc_errors/emitter.rs
493 fn stdout_isatty() -> bool {
494 unsafe { libc::isatty(libc::STDOUT_FILENO) != 0 }
498 fn stdout_isatty() -> bool {
499 use winapi::um::consoleapi::GetConsoleMode;
500 use winapi::um::processenv::GetStdHandle;
501 use winapi::um::winbase::STD_OUTPUT_HANDLE;
504 let handle = GetStdHandle(STD_OUTPUT_HANDLE);
506 GetConsoleMode(handle, &mut out) != 0
510 fn handle_explain(registry: Registry, code: &str, output: ErrorOutputType) {
512 if code.starts_with('E') { code.to_string() } else { format!("E{0:0>4}", code) };
513 match registry.try_find_description(&normalised) {
514 Ok(Some(description)) => {
515 let mut is_in_code_block = false;
516 let mut text = String::new();
517 // Slice off the leading newline and print.
518 for line in description.lines() {
520 line.find(|c: char| !c.is_whitespace()).unwrap_or_else(|| line.len());
521 let dedented_line = &line[indent_level..];
522 if dedented_line.starts_with("```") {
523 is_in_code_block = !is_in_code_block;
524 text.push_str(&line[..(indent_level + 3)]);
525 } else if is_in_code_block && dedented_line.starts_with("# ") {
533 show_content_with_pager(&text);
539 early_error(output, &format!("no extended information for {}", code));
541 Err(InvalidErrorCode) => {
542 early_error(output, &format!("{} is not a valid error code", code));
547 fn show_content_with_pager(content: &String) {
548 let pager_name = env::var_os("PAGER").unwrap_or_else(|| {
549 if cfg!(windows) { OsString::from("more.com") } else { OsString::from("less") }
552 let mut fallback_to_println = false;
554 match Command::new(pager_name).stdin(Stdio::piped()).spawn() {
556 if let Some(pipe) = pager.stdin.as_mut() {
557 if pipe.write_all(content.as_bytes()).is_err() {
558 fallback_to_println = true;
562 if pager.wait().is_err() {
563 fallback_to_println = true;
567 fallback_to_println = true;
571 // If pager fails for whatever reason, we should still print the content
572 // to standard output
573 if fallback_to_println {
574 print!("{}", content);
578 impl RustcDefaultCalls {
579 fn process_rlink(sess: &Session, compiler: &interface::Compiler) -> Result<(), ErrorReported> {
580 if let Input::File(file) = compiler.input() {
581 // FIXME: #![crate_type] and #![crate_name] support not implemented yet
583 sess.init_crate_types(collect_crate_types(sess, &attrs));
584 let outputs = compiler.build_output_filenames(&sess, &attrs);
585 let rlink_data = fs::read_to_string(file).unwrap_or_else(|err| {
586 sess.fatal(&format!("failed to read rlink file: {}", err));
588 let codegen_results: CodegenResults = json::decode(&rlink_data).unwrap_or_else(|err| {
589 sess.fatal(&format!("failed to decode rlink: {}", err));
591 compiler.codegen_backend().link(&sess, Box::new(codegen_results), &outputs)
593 sess.fatal("rlink must be a file")
597 pub fn try_process_rlink(sess: &Session, compiler: &interface::Compiler) -> Compilation {
598 if sess.opts.debugging_opts.link_only {
599 let result = RustcDefaultCalls::process_rlink(sess, compiler);
600 abort_on_err(result, sess);
603 Compilation::Continue
607 pub fn list_metadata(
609 metadata_loader: &dyn MetadataLoader,
610 matches: &getopts::Matches,
613 let r = matches.opt_strs("Z");
614 if r.iter().any(|s| *s == "ls") {
616 Input::File(ref ifile) => {
617 let path = &(*ifile);
618 let mut v = Vec::new();
619 locator::list_file_metadata(&sess.target.target, path, metadata_loader, &mut v)
621 println!("{}", String::from_utf8(v).unwrap());
623 Input::Str { .. } => {
624 early_error(ErrorOutputType::default(), "cannot list metadata for stdin");
627 return Compilation::Stop;
630 Compilation::Continue
634 codegen_backend: &dyn CodegenBackend,
636 input: Option<&Input>,
637 odir: &Option<PathBuf>,
638 ofile: &Option<PathBuf>,
640 use rustc_session::config::PrintRequest::*;
641 // PrintRequest::NativeStaticLibs is special - printed during linking
642 // (empty iterator returns true)
643 if sess.opts.prints.iter().all(|&p| p == PrintRequest::NativeStaticLibs) {
644 return Compilation::Continue;
647 let attrs = match input {
650 let result = parse_crate_attrs(sess, input);
652 Ok(attrs) => Some(attrs),
653 Err(mut parse_error) => {
655 return Compilation::Stop;
660 for req in &sess.opts.prints {
663 let mut targets = rustc_target::spec::get_targets().collect::<Vec<String>>();
665 println!("{}", targets.join("\n"));
667 Sysroot => println!("{}", sess.sysroot.display()),
668 TargetLibdir => println!(
670 sess.target_tlib_path.as_ref().unwrap_or(&sess.host_tlib_path).dir.display()
672 TargetSpec => println!("{}", sess.target.target.to_json().pretty()),
673 FileNames | CrateName => {
674 let input = input.unwrap_or_else(|| {
675 early_error(ErrorOutputType::default(), "no input file provided")
677 let attrs = attrs.as_ref().unwrap();
678 let t_outputs = rustc_interface::util::build_output_filenames(
679 input, odir, ofile, attrs, sess,
681 let id = rustc_session::output::find_crate_name(Some(sess), attrs, input);
682 if *req == PrintRequest::CrateName {
686 let crate_types = collect_crate_types(sess, attrs);
687 for &style in &crate_types {
689 rustc_session::output::filename_for_input(sess, style, &id, &t_outputs);
690 println!("{}", fname.file_name().unwrap().to_string_lossy());
694 let allow_unstable_cfg =
695 UnstableFeatures::from_environment().is_nightly_build();
701 .filter_map(|&(name, value)| {
702 // Note that crt-static is a specially recognized cfg
703 // directive that's printed out here as part of
704 // rust-lang/rust#37406, but in general the
705 // `target_feature` cfg is gated under
706 // rust-lang/rust#29717. For now this is just
707 // specifically allowing the crt-static cfg and that's
708 // it, this is intended to get into Cargo and then go
709 // through to build scripts.
710 if (name != sym::target_feature || value != Some(sym::crt_dash_static))
711 && !allow_unstable_cfg
712 && find_gated_cfg(|cfg_sym| cfg_sym == name).is_some()
717 if let Some(value) = value {
718 Some(format!("{}=\"{}\"", name, value))
720 Some(name.to_string())
723 .collect::<Vec<String>>();
730 RelocationModels | CodeModels | TlsModels | TargetCPUs | TargetFeatures => {
731 codegen_backend.print(*req, sess);
733 // Any output here interferes with Cargo's parsing of other printed output
734 PrintRequest::NativeStaticLibs => {}
741 /// Returns a version string such as "0.12.0-dev".
742 fn release_str() -> Option<&'static str> {
743 option_env!("CFG_RELEASE")
746 /// Returns the full SHA1 hash of HEAD of the Git repo from which rustc was built.
747 fn commit_hash_str() -> Option<&'static str> {
748 option_env!("CFG_VER_HASH")
751 /// Returns the "commit date" of HEAD of the Git repo from which rustc was built as a static string.
752 fn commit_date_str() -> Option<&'static str> {
753 option_env!("CFG_VER_DATE")
756 /// Prints version information
757 pub fn version(binary: &str, matches: &getopts::Matches) {
758 let verbose = matches.opt_present("verbose");
760 println!("{} {}", binary, option_env!("CFG_VERSION").unwrap_or("unknown version"));
763 fn unw(x: Option<&str>) -> &str {
764 x.unwrap_or("unknown")
766 println!("binary: {}", binary);
767 println!("commit-hash: {}", unw(commit_hash_str()));
768 println!("commit-date: {}", unw(commit_date_str()));
769 println!("host: {}", config::host_triple());
770 println!("release: {}", unw(release_str()));
771 get_builtin_codegen_backend("llvm")().print_version();
775 fn usage(verbose: bool, include_unstable_options: bool) {
776 let groups = if verbose { config::rustc_optgroups() } else { config::rustc_short_optgroups() };
777 let mut options = getopts::Options::new();
778 for option in groups.iter().filter(|x| include_unstable_options || x.is_stable()) {
779 (option.apply)(&mut options);
781 let message = "Usage: rustc [OPTIONS] INPUT";
782 let nightly_help = if nightly_options::is_nightly_build() {
783 "\n -Z help Print unstable compiler options"
787 let verbose_help = if verbose {
790 "\n --help -v Print the full set of options rustc accepts"
792 let at_path = if verbose && nightly_options::is_nightly_build() {
793 " @path Read newline separated options from `path`\n"
798 "{options}{at_path}\nAdditional help:
799 -C help Print codegen options
801 Print 'lint' options and default settings{nightly}{verbose}\n",
802 options = options.usage(message),
804 nightly = nightly_help,
805 verbose = verbose_help
809 fn print_wall_help() {
812 The flag `-Wall` does not exist in `rustc`. Most useful lints are enabled by
813 default. Use `rustc -W help` to see all available lints. It's more common to put
814 warning settings in the crate root using `#![warn(LINT_NAME)]` instead of using
815 the command line flag directly.
820 fn describe_lints(sess: &Session, lint_store: &LintStore, loaded_plugins: bool) {
823 Available lint options:
824 -W <foo> Warn about <foo>
828 -F <foo> Forbid <foo> \
829 (deny <foo> and all attempts to override)
834 fn sort_lints(sess: &Session, mut lints: Vec<&'static Lint>) -> Vec<&'static Lint> {
835 // The sort doesn't case-fold but it's doubtful we care.
836 lints.sort_by_cached_key(|x: &&Lint| (x.default_level(sess.edition()), x.name));
841 lints: Vec<(&'static str, Vec<LintId>, bool)>,
842 ) -> Vec<(&'static str, Vec<LintId>)> {
843 let mut lints: Vec<_> = lints.into_iter().map(|(x, y, _)| (x, y)).collect();
844 lints.sort_by_key(|l| l.0);
848 let (plugin, builtin): (Vec<_>, _) =
849 lint_store.get_lints().iter().cloned().partition(|&lint| lint.is_plugin);
850 let plugin = sort_lints(sess, plugin);
851 let builtin = sort_lints(sess, builtin);
853 let (plugin_groups, builtin_groups): (Vec<_>, _) =
854 lint_store.get_lint_groups().iter().cloned().partition(|&(.., p)| p);
855 let plugin_groups = sort_lint_groups(plugin_groups);
856 let builtin_groups = sort_lint_groups(builtin_groups);
859 plugin.iter().chain(&builtin).map(|&s| s.name.chars().count()).max().unwrap_or(0);
860 let padded = |x: &str| {
861 let mut s = " ".repeat(max_name_len - x.chars().count());
866 println!("Lint checks provided by rustc:\n");
867 println!(" {} {:7.7} {}", padded("name"), "default", "meaning");
868 println!(" {} {:7.7} {}", padded("----"), "-------", "-------");
870 let print_lints = |lints: Vec<&Lint>| {
872 let name = lint.name_lower().replace("_", "-");
873 println!(" {} {:7.7} {}", padded(&name), lint.default_level.as_str(), lint.desc);
878 print_lints(builtin);
880 let max_name_len = max(
884 .chain(&builtin_groups)
885 .map(|&(s, _)| s.chars().count())
890 let padded = |x: &str| {
891 let mut s = " ".repeat(max_name_len - x.chars().count());
896 println!("Lint groups provided by rustc:\n");
897 println!(" {} {}", padded("name"), "sub-lints");
898 println!(" {} {}", padded("----"), "---------");
899 println!(" {} {}", padded("warnings"), "all lints that are set to issue warnings");
901 let print_lint_groups = |lints: Vec<(&'static str, Vec<LintId>)>| {
902 for (name, to) in lints {
903 let name = name.to_lowercase().replace("_", "-");
906 .map(|x| x.to_string().replace("_", "-"))
907 .collect::<Vec<String>>()
909 println!(" {} {}", padded(&name), desc);
914 print_lint_groups(builtin_groups);
916 match (loaded_plugins, plugin.len(), plugin_groups.len()) {
917 (false, 0, _) | (false, _, 0) => {
919 "Compiler plugins can provide additional lints and lint groups. To see a \
920 listing of these, re-run `rustc -W help` with a crate filename."
923 (false, ..) => panic!("didn't load lint plugins but got them anyway!"),
924 (true, 0, 0) => println!("This crate does not load any lint plugins or lint groups."),
927 println!("Lint checks provided by plugins loaded by this crate:\n");
931 println!("Lint groups provided by plugins loaded by this crate:\n");
932 print_lint_groups(plugin_groups);
938 fn describe_debug_flags() {
939 println!("\nAvailable options:\n");
940 print_flag_list("-Z", config::DB_OPTIONS);
943 fn describe_codegen_flags() {
944 println!("\nAvailable codegen options:\n");
945 print_flag_list("-C", config::CG_OPTIONS);
948 fn print_flag_list<T>(
950 flag_list: &[(&'static str, T, &'static str, &'static str)],
952 let max_len = flag_list.iter().map(|&(name, _, _, _)| name.chars().count()).max().unwrap_or(0);
954 for &(name, _, _, desc) in flag_list {
956 " {} {:>width$}=val -- {}",
958 name.replace("_", "-"),
965 /// Process command line options. Emits messages as appropriate. If compilation
966 /// should continue, returns a getopts::Matches object parsed from args,
967 /// otherwise returns `None`.
969 /// The compiler's handling of options is a little complicated as it ties into
970 /// our stability story. The current intention of each compiler option is to
971 /// have one of two modes:
973 /// 1. An option is stable and can be used everywhere.
974 /// 2. An option is unstable, and can only be used on nightly.
976 /// Like unstable library and language features, however, unstable options have
977 /// always required a form of "opt in" to indicate that you're using them. This
978 /// provides the easy ability to scan a code base to check to see if anything
979 /// unstable is being used. Currently, this "opt in" is the `-Z` "zed" flag.
981 /// All options behind `-Z` are considered unstable by default. Other top-level
982 /// options can also be considered unstable, and they were unlocked through the
983 /// `-Z unstable-options` flag. Note that `-Z` remains to be the root of
984 /// instability in both cases, though.
986 /// So with all that in mind, the comments below have some more detail about the
987 /// contortions done here to get things to work out correctly.
988 pub fn handle_options(args: &[String]) -> Option<getopts::Matches> {
989 // Throw away the first argument, the name of the binary
990 let args = &args[1..];
993 // user did not write `-v` nor `-Z unstable-options`, so do not
994 // include that extra information.
999 // Parse with *all* options defined in the compiler, we don't worry about
1000 // option stability here we just want to parse as much as possible.
1001 let mut options = getopts::Options::new();
1002 for option in config::rustc_optgroups() {
1003 (option.apply)(&mut options);
1005 let matches = options
1007 .unwrap_or_else(|f| early_error(ErrorOutputType::default(), &f.to_string()));
1009 // For all options we just parsed, we check a few aspects:
1011 // * If the option is stable, we're all good
1012 // * If the option wasn't passed, we're all good
1013 // * If `-Z unstable-options` wasn't passed (and we're not a -Z option
1014 // ourselves), then we require the `-Z unstable-options` flag to unlock
1015 // this option that was passed.
1016 // * If we're a nightly compiler, then unstable options are now unlocked, so
1017 // we're good to go.
1018 // * Otherwise, if we're an unstable option then we generate an error
1019 // (unstable option being used on stable)
1020 nightly_options::check_nightly_options(&matches, &config::rustc_optgroups());
1022 if matches.opt_present("h") || matches.opt_present("help") {
1023 // Only show unstable options in --help if we accept unstable options.
1024 usage(matches.opt_present("verbose"), nightly_options::is_unstable_enabled(&matches));
1028 // Handle the special case of -Wall.
1029 let wall = matches.opt_strs("W");
1030 if wall.iter().any(|x| *x == "all") {
1035 // Don't handle -W help here, because we might first load plugins.
1036 let r = matches.opt_strs("Z");
1037 if r.iter().any(|x| *x == "help") {
1038 describe_debug_flags();
1042 let cg_flags = matches.opt_strs("C");
1044 if cg_flags.iter().any(|x| *x == "help") {
1045 describe_codegen_flags();
1049 if cg_flags.iter().any(|x| *x == "no-stack-check") {
1051 ErrorOutputType::default(),
1052 "the --no-stack-check flag is deprecated and does nothing",
1056 if cg_flags.iter().any(|x| *x == "passes=list") {
1057 get_builtin_codegen_backend("llvm")().print_passes();
1061 if matches.opt_present("version") {
1062 version("rustc", &matches);
1069 fn parse_crate_attrs<'a>(sess: &'a Session, input: &Input) -> PResult<'a, Vec<ast::Attribute>> {
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 args = env::args_os().map(|arg| arg.to_string_lossy().to_string()).collect::<Vec<_>>();
1088 // Avoid printing help because of empty args. This can suggest the compiler
1089 // itself is not the program root (consider RLS).
1094 let matches = handle_options(&args)?;
1095 let mut result = Vec::new();
1096 let mut excluded_cargo_defaults = false;
1097 for flag in ICE_REPORT_COMPILER_FLAGS {
1098 let prefix = if flag.len() == 1 { "-" } else { "--" };
1100 for content in &matches.opt_strs(flag) {
1101 // Split always returns the first element
1102 let name = if let Some(first) = content.split('=').next() { first } else { &content };
1105 if ICE_REPORT_COMPILER_FLAGS_STRIP_VALUE.contains(&name) { name } else { content };
1107 if !ICE_REPORT_COMPILER_FLAGS_EXCLUDE.contains(&name) {
1108 result.push(format!("{}{} {}", prefix, flag, content));
1110 excluded_cargo_defaults = true;
1115 if !result.is_empty() { Some((result, excluded_cargo_defaults)) } else { None }
1118 /// Runs a closure and catches unwinds triggered by fatal errors.
1120 /// The compiler currently unwinds with a special sentinel value to abort
1121 /// compilation on fatal errors. This function catches that sentinel and turns
1122 /// the panic into a `Result` instead.
1123 pub fn catch_fatal_errors<F: FnOnce() -> R, R>(f: F) -> Result<R, ErrorReported> {
1124 catch_unwind(panic::AssertUnwindSafe(f)).map_err(|value| {
1125 if value.is::<rustc_errors::FatalErrorMarker>() {
1128 panic::resume_unwind(value);
1133 /// Variant of `catch_fatal_errors` for the `interface::Result` return type
1134 /// that also computes the exit code.
1135 pub fn catch_with_exit_code(f: impl FnOnce() -> interface::Result<()>) -> i32 {
1136 let result = catch_fatal_errors(f).and_then(|result| result);
1138 Ok(()) => EXIT_SUCCESS,
1139 Err(_) => EXIT_FAILURE,
1144 static ref DEFAULT_HOOK: Box<dyn Fn(&panic::PanicInfo<'_>) + Sync + Send + 'static> = {
1145 let hook = panic::take_hook();
1146 panic::set_hook(Box::new(|info| report_ice(info, BUG_REPORT_URL)));
1151 /// Prints the ICE message, including backtrace and query stack.
1153 /// The message will point the user at `bug_report_url` to report the ICE.
1155 /// When `install_ice_hook` is called, this function will be called as the panic
1157 pub fn report_ice(info: &panic::PanicInfo<'_>, bug_report_url: &str) {
1158 // Invoke the default handler, which prints the actual panic message and optionally a backtrace
1159 (*DEFAULT_HOOK)(info);
1161 // Separate the output with an empty line
1164 let emitter = Box::new(rustc_errors::emitter::EmitterWriter::stderr(
1165 rustc_errors::ColorConfig::Auto,
1172 let handler = rustc_errors::Handler::with_emitter(true, None, emitter);
1174 // a .span_bug or .bug call has already printed what
1175 // it wants to print.
1176 if !info.payload().is::<rustc_errors::ExplicitBug>() {
1177 let d = rustc_errors::Diagnostic::new(rustc_errors::Level::Bug, "unexpected panic");
1178 handler.emit_diagnostic(&d);
1181 let mut xs: Vec<Cow<'static, str>> = vec![
1182 "the compiler unexpectedly panicked. this is a bug.".into(),
1183 format!("we would appreciate a bug report: {}", bug_report_url).into(),
1185 "rustc {} running on {}",
1186 option_env!("CFG_VERSION").unwrap_or("unknown_version"),
1187 config::host_triple()
1192 if let Some((flags, excluded_cargo_defaults)) = extra_compiler_flags() {
1193 xs.push(format!("compiler flags: {}", flags.join(" ")).into());
1195 if excluded_cargo_defaults {
1196 xs.push("some of the compiler flags provided by cargo are hidden".into());
1201 handler.note_without_error(¬e);
1204 // If backtraces are enabled, also print the query stack
1205 let backtrace = env::var_os("RUST_BACKTRACE").map(|x| &x != "0").unwrap_or(false);
1208 TyCtxt::try_print_query_stack(&handler);
1213 if env::var("RUSTC_BREAK_ON_ICE").is_ok() {
1214 // Trigger a debugger if we crashed during bootstrap
1215 winapi::um::debugapi::DebugBreak();
1220 /// Installs a panic hook that will print the ICE message on unexpected panics.
1222 /// A custom rustc driver can skip calling this to set up a custom ICE hook.
1223 pub fn install_ice_hook() {
1224 lazy_static::initialize(&DEFAULT_HOOK);
1227 /// This allows tools to enable rust logging without having to magically match rustc's
1228 /// log crate version
1229 pub fn init_rustc_env_logger() {
1230 env_logger::init_from_env("RUSTC_LOG");
1233 pub fn main() -> ! {
1234 let start = Instant::now();
1235 init_rustc_env_logger();
1236 let mut callbacks = TimePassesCallbacks::default();
1238 let exit_code = catch_with_exit_code(|| {
1239 let args = env::args_os()
1242 arg.into_string().unwrap_or_else(|arg| {
1244 ErrorOutputType::default(),
1245 &format!("Argument {} is not valid Unicode: {:?}", i, arg),
1249 .collect::<Vec<_>>();
1250 run_compiler(&args, &mut callbacks, None, None)
1252 // The extra `\t` is necessary to align this label with the others.
1253 print_time_passes_entry(callbacks.time_passes, "\ttotal", start.elapsed());
1254 process::exit(exit_code)