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;
21 use rustc::lint::{Lint, LintId};
22 use rustc::middle::cstore::MetadataLoader;
23 use rustc::session::config::nightly_options;
24 use rustc::session::config::{ErrorOutputType, Input, OutputType, PrintRequest};
25 use rustc::session::{config, DiagnosticOutput, Session};
26 use rustc::session::{early_error, early_warn};
27 use rustc::ty::TyCtxt;
28 use rustc::util::common::ErrorReported;
29 use rustc_codegen_utils::codegen_backend::CodegenBackend;
30 use rustc_data_structures::profiling::print_time_passes_entry;
31 use rustc_data_structures::sync::SeqCst;
32 use rustc_errors::{registry::Registry, PResult};
33 use rustc_feature::{find_gated_cfg, UnstableFeatures};
34 use rustc_hir::def_id::LOCAL_CRATE;
35 use rustc_interface::util::get_builtin_codegen_backend;
36 use rustc_interface::{interface, Queries};
37 use rustc_lint::LintStore;
38 use rustc_metadata::locator;
39 use rustc_save_analysis as save;
40 use rustc_save_analysis::DumpHandler;
41 use rustc_serialize::json::ToJson;
45 use std::default::Default;
47 use std::ffi::OsString;
48 use std::io::{self, Read, Write};
50 use std::panic::{self, catch_unwind};
51 use std::path::PathBuf;
52 use std::process::{self, Command, Stdio};
54 use std::time::Instant;
56 use rustc_span::source_map::FileLoader;
57 use rustc_span::symbol::sym;
58 use rustc_span::FileName;
64 /// Exit status code used for successful compilation and help output.
65 pub const EXIT_SUCCESS: i32 = 0;
67 /// Exit status code used for compilation failures and invalid flags.
68 pub const EXIT_FAILURE: i32 = 1;
70 const BUG_REPORT_URL: &str = "https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.\
73 const ICE_REPORT_COMPILER_FLAGS: &[&str] = &["Z", "C", "crate-type"];
75 const ICE_REPORT_COMPILER_FLAGS_EXCLUDE: &[&str] = &["metadata", "extra-filename"];
77 const ICE_REPORT_COMPILER_FLAGS_STRIP_VALUE: &[&str] = &["incremental"];
79 pub fn abort_on_err<T>(result: Result<T, ErrorReported>, sess: &Session) -> T {
82 sess.abort_if_errors();
83 panic!("error reported but abort_if_errors didn't abort???");
90 /// Called before creating the compiler instance
91 fn config(&mut self, _config: &mut interface::Config) {}
92 /// Called after parsing. Return value instructs the compiler whether to
93 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
94 fn after_parsing<'tcx>(
96 _compiler: &interface::Compiler,
97 _queries: &'tcx Queries<'tcx>,
101 /// Called after expansion. Return value instructs the compiler whether to
102 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
103 fn after_expansion<'tcx>(
105 _compiler: &interface::Compiler,
106 _queries: &'tcx Queries<'tcx>,
108 Compilation::Continue
110 /// Called after analysis. Return value instructs the compiler whether to
111 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
112 fn after_analysis<'tcx>(
114 _compiler: &interface::Compiler,
115 _queries: &'tcx Queries<'tcx>,
117 Compilation::Continue
121 pub struct DefaultCallbacks;
123 impl Callbacks for DefaultCallbacks {}
126 pub struct TimePassesCallbacks {
130 impl Callbacks for TimePassesCallbacks {
131 fn config(&mut self, config: &mut interface::Config) {
132 // If a --prints=... option has been given, we don't print the "total"
133 // time because it will mess up the --prints output. See #64339.
134 self.time_passes = config.opts.prints.is_empty()
135 && (config.opts.debugging_opts.time_passes || config.opts.debugging_opts.time);
139 pub fn diagnostics_registry() -> Registry {
140 Registry::new(&rustc_error_codes::DIAGNOSTICS)
143 // Parse args and run the compiler. This is the primary entry point for rustc.
144 // See comments on CompilerCalls below for details about the callbacks argument.
145 // The FileLoader provides a way to load files from sources other than the file system.
148 callbacks: &mut (dyn Callbacks + Send),
149 file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
150 emitter: Option<Box<dyn Write + Send>>,
151 ) -> interface::Result<()> {
152 let mut args = Vec::new();
154 match args::arg_expand(arg.clone()) {
155 Ok(arg) => args.extend(arg),
156 Err(err) => early_error(
157 ErrorOutputType::default(),
158 &format!("Failed to load argument file: {}", err),
162 let diagnostic_output =
163 emitter.map(|emitter| DiagnosticOutput::Raw(emitter)).unwrap_or(DiagnosticOutput::Default);
164 let matches = match handle_options(&args) {
165 Some(matches) => matches,
166 None => return Ok(()),
169 let sopts = config::build_session_options(&matches);
170 let cfg = interface::parse_cfgspecs(matches.opt_strs("cfg"));
172 let mut dummy_config = |sopts, cfg, diagnostic_output| {
173 let mut config = interface::Config {
176 input: Input::File(PathBuf::new()),
184 lint_caps: Default::default(),
185 register_lints: None,
186 override_queries: None,
187 registry: diagnostics_registry(),
189 callbacks.config(&mut config);
193 if let Some(ref code) = matches.opt_str("explain") {
194 handle_explain(diagnostics_registry(), code, sopts.error_format);
198 let (odir, ofile) = make_output(&matches);
199 let (input, input_file_path, input_err) = match make_input(&matches.free) {
201 None => match matches.free.len() {
203 let config = dummy_config(sopts, cfg, diagnostic_output);
204 interface::run_compiler(config, |compiler| {
205 let sopts = &compiler.session().opts;
206 if sopts.describe_lints {
207 let lint_store = rustc_lint::new_lint_store(
208 sopts.debugging_opts.no_interleave_lints,
209 compiler.session().unstable_options(),
211 describe_lints(compiler.session(), &lint_store, false);
214 let should_stop = RustcDefaultCalls::print_crate_info(
215 &***compiler.codegen_backend(),
222 if should_stop == Compilation::Stop {
225 early_error(sopts.error_format, "no input filename given")
229 1 => panic!("make_input should have provided valid inputs"),
233 "multiple input filenames provided (first two filenames are `{}` and `{}`)",
234 matches.free[0], matches.free[1],
240 if let Some(err) = input_err {
241 // Immediately stop compilation if there was an issue reading
242 // the input (for example if the input stream is not UTF-8).
243 interface::run_compiler(dummy_config(sopts, cfg, diagnostic_output), |compiler| {
244 compiler.session().err(&err.to_string());
246 return Err(ErrorReported);
249 let mut config = interface::Config {
253 input_path: input_file_path,
260 lint_caps: Default::default(),
261 register_lints: None,
262 override_queries: None,
263 registry: diagnostics_registry(),
266 callbacks.config(&mut config);
268 interface::run_compiler(config, |compiler| {
269 let sess = compiler.session();
270 let should_stop = RustcDefaultCalls::print_crate_info(
271 &***compiler.codegen_backend(),
273 Some(compiler.input()),
274 compiler.output_dir(),
275 compiler.output_file(),
278 RustcDefaultCalls::list_metadata(
280 &*compiler.codegen_backend().metadata_loader(),
286 if should_stop == Compilation::Stop {
287 return sess.compile_status();
290 let linker = compiler.enter(|queries| {
291 let early_exit = || sess.compile_status().map(|_| None);
294 if let Some(ppm) = &sess.opts.pretty {
295 if ppm.needs_ast_map() {
296 queries.global_ctxt()?.peek_mut().enter(|tcx| {
297 let expanded_crate = queries.expansion()?.take().0;
298 pretty::print_after_hir_lowering(
303 compiler.output_file().as_ref().map(|p| &**p),
308 let krate = queries.parse()?.take();
309 pretty::print_after_parsing(
314 compiler.output_file().as_ref().map(|p| &**p),
320 if callbacks.after_parsing(compiler, queries) == Compilation::Stop {
324 if sess.opts.debugging_opts.parse_only
325 || sess.opts.debugging_opts.show_span.is_some()
326 || sess.opts.debugging_opts.ast_json_noexpand
332 let (_, lint_store) = &*queries.register_plugins()?.peek();
334 // Lint plugins are registered; now we can process command line flags.
335 if sess.opts.describe_lints {
336 describe_lints(&sess, &lint_store, true);
341 queries.expansion()?;
342 if callbacks.after_expansion(compiler, queries) == Compilation::Stop {
346 queries.prepare_outputs()?;
348 if sess.opts.output_types.contains_key(&OutputType::DepInfo)
349 && sess.opts.output_types.len() == 1
354 queries.global_ctxt()?;
356 if sess.opts.debugging_opts.no_analysis || sess.opts.debugging_opts.ast_json {
360 if sess.opts.debugging_opts.save_analysis {
361 let expanded_crate = &queries.expansion()?.peek().0;
362 let crate_name = queries.crate_name()?.peek().clone();
363 queries.global_ctxt()?.peek_mut().enter(|tcx| {
364 let result = tcx.analysis(LOCAL_CRATE);
366 sess.time("save_analysis", || {
374 compiler.output_dir().as_ref().map(|p| &**p),
381 // AST will be dropped *after* the `after_analysis` callback
382 // (needed by the RLS)
385 // Drop AST after creating GlobalCtxt to free memory
386 let _timer = sess.prof.generic_activity("drop_ast");
387 mem::drop(queries.expansion()?.take());
390 queries.global_ctxt()?.peek_mut().enter(|tcx| tcx.analysis(LOCAL_CRATE))?;
392 if callbacks.after_analysis(compiler, queries) == Compilation::Stop {
396 if sess.opts.debugging_opts.save_analysis {
397 mem::drop(queries.expansion()?.take());
400 queries.ongoing_codegen()?;
402 if sess.opts.debugging_opts.print_type_sizes {
403 sess.code_stats.print_type_sizes();
406 let linker = queries.linker()?;
410 if let Some(linker) = linker {
411 let _timer = sess.timer("link");
415 if sess.opts.debugging_opts.perf_stats {
416 sess.print_perf_stats();
419 if sess.print_fuel_crate.is_some() {
421 "Fuel used by {}: {}",
422 sess.print_fuel_crate.as_ref().unwrap(),
423 sess.print_fuel.load(SeqCst)
432 pub fn set_sigpipe_handler() {
434 // Set the SIGPIPE signal handler, so that an EPIPE
435 // will cause rustc to terminate, as expected.
436 assert_ne!(libc::signal(libc::SIGPIPE, libc::SIG_DFL), libc::SIG_ERR);
441 pub fn set_sigpipe_handler() {}
443 // Extract output directory and file from matches.
444 fn make_output(matches: &getopts::Matches) -> (Option<PathBuf>, Option<PathBuf>) {
445 let odir = matches.opt_str("out-dir").map(|o| PathBuf::from(&o));
446 let ofile = matches.opt_str("o").map(|o| PathBuf::from(&o));
450 // Extract input (string or file and optional path) from matches.
451 fn make_input(free_matches: &[String]) -> Option<(Input, Option<PathBuf>, Option<io::Error>)> {
452 if free_matches.len() == 1 {
453 let ifile = &free_matches[0];
455 let mut src = String::new();
456 let err = if io::stdin().read_to_string(&mut src).is_err() {
458 io::ErrorKind::InvalidData,
459 "couldn't read from stdin, as it did not contain valid UTF-8",
464 if let Ok(path) = env::var("UNSTABLE_RUSTDOC_TEST_PATH") {
465 let line = env::var("UNSTABLE_RUSTDOC_TEST_LINE").expect(
466 "when UNSTABLE_RUSTDOC_TEST_PATH is set \
467 UNSTABLE_RUSTDOC_TEST_LINE also needs to be set",
469 let line = isize::from_str_radix(&line, 10)
470 .expect("UNSTABLE_RUSTDOC_TEST_LINE needs to be an number");
471 let file_name = FileName::doc_test_source_code(PathBuf::from(path), line);
472 return Some((Input::Str { name: file_name, input: src }, None, err));
474 Some((Input::Str { name: FileName::anon_source_code(&src), input: src }, None, err))
476 Some((Input::File(PathBuf::from(ifile)), Some(PathBuf::from(ifile)), None))
483 // Whether to stop or continue compilation.
484 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
485 pub enum Compilation {
491 pub fn and_then<F: FnOnce() -> Compilation>(self, next: F) -> Compilation {
493 Compilation::Stop => Compilation::Stop,
494 Compilation::Continue => next(),
499 /// CompilerCalls instance for a regular rustc build.
500 #[derive(Copy, Clone)]
501 pub struct RustcDefaultCalls;
503 // FIXME remove these and use winapi 0.3 instead
504 // Duplicates: bootstrap/compile.rs, librustc_errors/emitter.rs
506 fn stdout_isatty() -> bool {
507 unsafe { libc::isatty(libc::STDOUT_FILENO) != 0 }
511 fn stdout_isatty() -> bool {
512 use winapi::um::consoleapi::GetConsoleMode;
513 use winapi::um::processenv::GetStdHandle;
514 use winapi::um::winbase::STD_OUTPUT_HANDLE;
517 let handle = GetStdHandle(STD_OUTPUT_HANDLE);
519 GetConsoleMode(handle, &mut out) != 0
523 fn handle_explain(registry: Registry, code: &str, output: ErrorOutputType) {
525 if code.starts_with("E") { code.to_string() } else { format!("E{0:0>4}", code) };
526 match registry.find_description(&normalised) {
527 Some(ref description) => {
528 let mut is_in_code_block = false;
529 let mut text = String::new();
531 // Slice off the leading newline and print.
532 for line in description.lines() {
534 line.find(|c: char| !c.is_whitespace()).unwrap_or_else(|| line.len());
535 let dedented_line = &line[indent_level..];
536 if dedented_line.starts_with("```") {
537 is_in_code_block = !is_in_code_block;
538 text.push_str(&line[..(indent_level + 3)]);
539 } else if is_in_code_block && dedented_line.starts_with("# ") {
548 show_content_with_pager(&text);
554 early_error(output, &format!("no extended information for {}", code));
559 fn show_content_with_pager(content: &String) {
560 let pager_name = env::var_os("PAGER").unwrap_or_else(|| {
561 if cfg!(windows) { OsString::from("more.com") } else { OsString::from("less") }
564 let mut fallback_to_println = false;
566 match Command::new(pager_name).stdin(Stdio::piped()).spawn() {
568 if let Some(pipe) = pager.stdin.as_mut() {
569 if pipe.write_all(content.as_bytes()).is_err() {
570 fallback_to_println = true;
574 if pager.wait().is_err() {
575 fallback_to_println = true;
579 fallback_to_println = true;
583 // If pager fails for whatever reason, we should still print the content
584 // to standard output
585 if fallback_to_println {
586 print!("{}", content);
590 impl RustcDefaultCalls {
591 pub fn list_metadata(
593 metadata_loader: &dyn MetadataLoader,
594 matches: &getopts::Matches,
597 let r = matches.opt_strs("Z");
598 if r.iter().any(|s| *s == "ls") {
600 &Input::File(ref ifile) => {
601 let path = &(*ifile);
602 let mut v = Vec::new();
603 locator::list_file_metadata(&sess.target.target, path, metadata_loader, &mut v)
605 println!("{}", String::from_utf8(v).unwrap());
607 &Input::Str { .. } => {
608 early_error(ErrorOutputType::default(), "cannot list metadata for stdin");
611 return Compilation::Stop;
614 Compilation::Continue
618 codegen_backend: &dyn CodegenBackend,
620 input: Option<&Input>,
621 odir: &Option<PathBuf>,
622 ofile: &Option<PathBuf>,
624 use rustc::session::config::PrintRequest::*;
625 // PrintRequest::NativeStaticLibs is special - printed during linking
626 // (empty iterator returns true)
627 if sess.opts.prints.iter().all(|&p| p == PrintRequest::NativeStaticLibs) {
628 return Compilation::Continue;
631 let attrs = match input {
634 let result = parse_crate_attrs(sess, input);
636 Ok(attrs) => Some(attrs),
637 Err(mut parse_error) => {
639 return Compilation::Stop;
644 for req in &sess.opts.prints {
647 let mut targets = rustc_target::spec::get_targets().collect::<Vec<String>>();
649 println!("{}", targets.join("\n"));
651 Sysroot => println!("{}", sess.sysroot.display()),
652 TargetSpec => println!("{}", sess.target.target.to_json().pretty()),
653 FileNames | CrateName => {
654 let input = input.unwrap_or_else(|| {
655 early_error(ErrorOutputType::default(), "no input file provided")
657 let attrs = attrs.as_ref().unwrap();
658 let t_outputs = rustc_interface::util::build_output_filenames(
659 input, odir, ofile, attrs, sess,
661 let id = rustc_codegen_utils::link::find_crate_name(Some(sess), attrs, input);
662 if *req == PrintRequest::CrateName {
666 let crate_types = rustc_interface::util::collect_crate_types(sess, attrs);
667 for &style in &crate_types {
668 let fname = rustc_codegen_utils::link::filename_for_input(
669 sess, style, &id, &t_outputs,
671 println!("{}", fname.file_name().unwrap().to_string_lossy());
675 let allow_unstable_cfg =
676 UnstableFeatures::from_environment().is_nightly_build();
682 .filter_map(|&(name, ref value)| {
683 // Note that crt-static is a specially recognized cfg
684 // directive that's printed out here as part of
685 // rust-lang/rust#37406, but in general the
686 // `target_feature` cfg is gated under
687 // rust-lang/rust#29717. For now this is just
688 // specifically allowing the crt-static cfg and that's
689 // it, this is intended to get into Cargo and then go
690 // through to build scripts.
691 let value = value.as_ref().map(|s| s.as_str());
692 let value = value.as_ref().map(|s| s.as_ref());
693 if (name != sym::target_feature || value != Some("crt-static"))
694 && !allow_unstable_cfg
695 && find_gated_cfg(|cfg_sym| cfg_sym == name).is_some()
700 if let Some(value) = value {
701 Some(format!("{}=\"{}\"", name, value))
703 Some(name.to_string())
706 .collect::<Vec<String>>();
713 RelocationModels | CodeModels | TlsModels | TargetCPUs | TargetFeatures => {
714 codegen_backend.print(*req, sess);
716 // Any output here interferes with Cargo's parsing of other printed output
717 PrintRequest::NativeStaticLibs => {}
720 return Compilation::Stop;
724 /// Returns a version string such as "0.12.0-dev".
725 fn release_str() -> Option<&'static str> {
726 option_env!("CFG_RELEASE")
729 /// Returns the full SHA1 hash of HEAD of the Git repo from which rustc was built.
730 fn commit_hash_str() -> Option<&'static str> {
731 option_env!("CFG_VER_HASH")
734 /// Returns the "commit date" of HEAD of the Git repo from which rustc was built as a static string.
735 fn commit_date_str() -> Option<&'static str> {
736 option_env!("CFG_VER_DATE")
739 /// Prints version information
740 pub fn version(binary: &str, matches: &getopts::Matches) {
741 let verbose = matches.opt_present("verbose");
743 println!("{} {}", binary, option_env!("CFG_VERSION").unwrap_or("unknown version"));
746 fn unw(x: Option<&str>) -> &str {
747 x.unwrap_or("unknown")
749 println!("binary: {}", binary);
750 println!("commit-hash: {}", unw(commit_hash_str()));
751 println!("commit-date: {}", unw(commit_date_str()));
752 println!("host: {}", config::host_triple());
753 println!("release: {}", unw(release_str()));
754 get_builtin_codegen_backend("llvm")().print_version();
758 fn usage(verbose: bool, include_unstable_options: bool) {
759 let groups = if verbose { config::rustc_optgroups() } else { config::rustc_short_optgroups() };
760 let mut options = getopts::Options::new();
761 for option in groups.iter().filter(|x| include_unstable_options || x.is_stable()) {
762 (option.apply)(&mut options);
764 let message = "Usage: rustc [OPTIONS] INPUT";
765 let nightly_help = if nightly_options::is_nightly_build() {
766 "\n -Z help Print unstable compiler options"
770 let verbose_help = if verbose {
773 "\n --help -v Print the full set of options rustc accepts"
775 let at_path = if verbose && nightly_options::is_nightly_build() {
776 " @path Read newline separated options from `path`\n"
781 "{options}{at_path}\nAdditional help:
782 -C help Print codegen options
784 Print 'lint' options and default settings{nightly}{verbose}\n",
785 options = options.usage(message),
787 nightly = nightly_help,
788 verbose = verbose_help
792 fn print_wall_help() {
795 The flag `-Wall` does not exist in `rustc`. Most useful lints are enabled by
796 default. Use `rustc -W help` to see all available lints. It's more common to put
797 warning settings in the crate root using `#![warn(LINT_NAME)]` instead of using
798 the command line flag directly.
803 fn describe_lints(sess: &Session, lint_store: &LintStore, loaded_plugins: bool) {
806 Available lint options:
807 -W <foo> Warn about <foo>
811 -F <foo> Forbid <foo> \
812 (deny <foo> and all attempts to override)
817 fn sort_lints(sess: &Session, mut lints: Vec<&'static Lint>) -> Vec<&'static Lint> {
818 // The sort doesn't case-fold but it's doubtful we care.
819 lints.sort_by_cached_key(|x: &&Lint| (x.default_level(sess.edition()), x.name));
824 lints: Vec<(&'static str, Vec<LintId>, bool)>,
825 ) -> Vec<(&'static str, Vec<LintId>)> {
826 let mut lints: Vec<_> = lints.into_iter().map(|(x, y, _)| (x, y)).collect();
827 lints.sort_by_key(|l| l.0);
831 let (plugin, builtin): (Vec<_>, _) =
832 lint_store.get_lints().iter().cloned().partition(|&lint| lint.is_plugin);
833 let plugin = sort_lints(sess, plugin);
834 let builtin = sort_lints(sess, builtin);
836 let (plugin_groups, builtin_groups): (Vec<_>, _) =
837 lint_store.get_lint_groups().iter().cloned().partition(|&(.., p)| p);
838 let plugin_groups = sort_lint_groups(plugin_groups);
839 let builtin_groups = sort_lint_groups(builtin_groups);
842 plugin.iter().chain(&builtin).map(|&s| s.name.chars().count()).max().unwrap_or(0);
843 let padded = |x: &str| {
844 let mut s = " ".repeat(max_name_len - x.chars().count());
849 println!("Lint checks provided by rustc:\n");
850 println!(" {} {:7.7} {}", padded("name"), "default", "meaning");
851 println!(" {} {:7.7} {}", padded("----"), "-------", "-------");
853 let print_lints = |lints: Vec<&Lint>| {
855 let name = lint.name_lower().replace("_", "-");
856 println!(" {} {:7.7} {}", padded(&name), lint.default_level.as_str(), lint.desc);
861 print_lints(builtin);
863 let max_name_len = max(
867 .chain(&builtin_groups)
868 .map(|&(s, _)| s.chars().count())
873 let padded = |x: &str| {
874 let mut s = " ".repeat(max_name_len - x.chars().count());
879 println!("Lint groups provided by rustc:\n");
880 println!(" {} {}", padded("name"), "sub-lints");
881 println!(" {} {}", padded("----"), "---------");
882 println!(" {} {}", padded("warnings"), "all lints that are set to issue warnings");
884 let print_lint_groups = |lints: Vec<(&'static str, Vec<LintId>)>| {
885 for (name, to) in lints {
886 let name = name.to_lowercase().replace("_", "-");
889 .map(|x| x.to_string().replace("_", "-"))
890 .collect::<Vec<String>>()
892 println!(" {} {}", padded(&name), desc);
897 print_lint_groups(builtin_groups);
899 match (loaded_plugins, plugin.len(), plugin_groups.len()) {
900 (false, 0, _) | (false, _, 0) => {
902 "Compiler plugins can provide additional lints and lint groups. To see a \
903 listing of these, re-run `rustc -W help` with a crate filename."
906 (false, ..) => panic!("didn't load lint plugins but got them anyway!"),
907 (true, 0, 0) => println!("This crate does not load any lint plugins or lint groups."),
910 println!("Lint checks provided by plugins loaded by this crate:\n");
914 println!("Lint groups provided by plugins loaded by this crate:\n");
915 print_lint_groups(plugin_groups);
921 fn describe_debug_flags() {
922 println!("\nAvailable options:\n");
923 print_flag_list("-Z", config::DB_OPTIONS);
926 fn describe_codegen_flags() {
927 println!("\nAvailable codegen options:\n");
928 print_flag_list("-C", config::CG_OPTIONS);
931 fn print_flag_list<T>(
933 flag_list: &[(&'static str, T, Option<&'static str>, &'static str)],
935 let max_len = flag_list
937 .map(|&(name, _, opt_type_desc, _)| {
938 let extra_len = match opt_type_desc {
942 name.chars().count() + extra_len
947 for &(name, _, opt_type_desc, desc) in flag_list {
948 let (width, extra) = match opt_type_desc {
949 Some(..) => (max_len - 4, "=val"),
950 None => (max_len, ""),
953 " {} {:>width$}{} -- {}",
955 name.replace("_", "-"),
963 /// Process command line options. Emits messages as appropriate. If compilation
964 /// should continue, returns a getopts::Matches object parsed from args,
965 /// otherwise returns `None`.
967 /// The compiler's handling of options is a little complicated as it ties into
968 /// our stability story. The current intention of each compiler option is to
969 /// have one of two modes:
971 /// 1. An option is stable and can be used everywhere.
972 /// 2. An option is unstable, and can only be used on nightly.
974 /// Like unstable library and language features, however, unstable options have
975 /// always required a form of "opt in" to indicate that you're using them. This
976 /// provides the easy ability to scan a code base to check to see if anything
977 /// unstable is being used. Currently, this "opt in" is the `-Z` "zed" flag.
979 /// All options behind `-Z` are considered unstable by default. Other top-level
980 /// options can also be considered unstable, and they were unlocked through the
981 /// `-Z unstable-options` flag. Note that `-Z` remains to be the root of
982 /// instability in both cases, though.
984 /// So with all that in mind, the comments below have some more detail about the
985 /// contortions done here to get things to work out correctly.
986 pub fn handle_options(args: &[String]) -> Option<getopts::Matches> {
987 // Throw away the first argument, the name of the binary
988 let args = &args[1..];
991 // user did not write `-v` nor `-Z unstable-options`, so do not
992 // include that extra information.
997 // Parse with *all* options defined in the compiler, we don't worry about
998 // option stability here we just want to parse as much as possible.
999 let mut options = getopts::Options::new();
1000 for option in config::rustc_optgroups() {
1001 (option.apply)(&mut options);
1003 let matches = options
1005 .unwrap_or_else(|f| early_error(ErrorOutputType::default(), &f.to_string()));
1007 // For all options we just parsed, we check a few aspects:
1009 // * If the option is stable, we're all good
1010 // * If the option wasn't passed, we're all good
1011 // * If `-Z unstable-options` wasn't passed (and we're not a -Z option
1012 // ourselves), then we require the `-Z unstable-options` flag to unlock
1013 // this option that was passed.
1014 // * If we're a nightly compiler, then unstable options are now unlocked, so
1015 // we're good to go.
1016 // * Otherwise, if we're an unstable option then we generate an error
1017 // (unstable option being used on stable)
1018 nightly_options::check_nightly_options(&matches, &config::rustc_optgroups());
1020 if matches.opt_present("h") || matches.opt_present("help") {
1021 // Only show unstable options in --help if we accept unstable options.
1022 usage(matches.opt_present("verbose"), nightly_options::is_unstable_enabled(&matches));
1026 // Handle the special case of -Wall.
1027 let wall = matches.opt_strs("W");
1028 if wall.iter().any(|x| *x == "all") {
1033 // Don't handle -W help here, because we might first load plugins.
1034 let r = matches.opt_strs("Z");
1035 if r.iter().any(|x| *x == "help") {
1036 describe_debug_flags();
1040 let cg_flags = matches.opt_strs("C");
1042 if cg_flags.iter().any(|x| *x == "help") {
1043 describe_codegen_flags();
1047 if cg_flags.iter().any(|x| *x == "no-stack-check") {
1049 ErrorOutputType::default(),
1050 "the --no-stack-check flag is deprecated and does nothing",
1054 if cg_flags.iter().any(|x| *x == "passes=list") {
1055 get_builtin_codegen_backend("llvm")().print_passes();
1059 if matches.opt_present("version") {
1060 version("rustc", &matches);
1067 fn parse_crate_attrs<'a>(sess: &'a Session, input: &Input) -> PResult<'a, Vec<ast::Attribute>> {
1069 Input::File(ifile) => rustc_parse::parse_crate_attrs_from_file(ifile, &sess.parse_sess),
1070 Input::Str { name, input } => rustc_parse::parse_crate_attrs_from_source_str(
1078 /// Gets a list of extra command-line flags provided by the user, as strings.
1080 /// This function is used during ICEs to show more information useful for
1081 /// debugging, since some ICEs only happens with non-default compiler flags
1082 /// (and the users don't always report them).
1083 fn extra_compiler_flags() -> Option<(Vec<String>, bool)> {
1084 let args = env::args_os().map(|arg| arg.to_string_lossy().to_string()).collect::<Vec<_>>();
1086 // Avoid printing help because of empty args. This can suggest the compiler
1087 // itself is not the program root (consider RLS).
1092 let matches = if let Some(matches) = handle_options(&args) {
1098 let mut result = Vec::new();
1099 let mut excluded_cargo_defaults = false;
1100 for flag in ICE_REPORT_COMPILER_FLAGS {
1101 let prefix = if flag.len() == 1 { "-" } else { "--" };
1103 for content in &matches.opt_strs(flag) {
1104 // Split always returns the first element
1105 let name = if let Some(first) = content.split('=').next() { first } else { &content };
1108 if ICE_REPORT_COMPILER_FLAGS_STRIP_VALUE.contains(&name) { name } else { content };
1110 if !ICE_REPORT_COMPILER_FLAGS_EXCLUDE.contains(&name) {
1111 result.push(format!("{}{} {}", prefix, flag, content));
1113 excluded_cargo_defaults = true;
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, ErrorReported> {
1127 catch_unwind(panic::AssertUnwindSafe(f)).map_err(|value| {
1128 if value.is::<rustc_errors::FatalErrorMarker>() {
1131 panic::resume_unwind(value);
1137 static ref DEFAULT_HOOK: Box<dyn Fn(&panic::PanicInfo<'_>) + Sync + Send + 'static> = {
1138 let hook = panic::take_hook();
1139 panic::set_hook(Box::new(|info| report_ice(info, BUG_REPORT_URL)));
1144 /// Prints the ICE message, including backtrace and query stack.
1146 /// The message will point the user at `bug_report_url` to report the ICE.
1148 /// When `install_ice_hook` is called, this function will be called as the panic
1150 pub fn report_ice(info: &panic::PanicInfo<'_>, bug_report_url: &str) {
1151 // Invoke the default handler, which prints the actual panic message and optionally a backtrace
1152 (*DEFAULT_HOOK)(info);
1154 // Separate the output with an empty line
1157 let emitter = Box::new(rustc_errors::emitter::EmitterWriter::stderr(
1158 rustc_errors::ColorConfig::Auto,
1165 let handler = rustc_errors::Handler::with_emitter(true, None, emitter);
1167 // a .span_bug or .bug call has already printed what
1168 // it wants to print.
1169 if !info.payload().is::<rustc_errors::ExplicitBug>() {
1170 let d = rustc_errors::Diagnostic::new(rustc_errors::Level::Bug, "unexpected panic");
1171 handler.emit_diagnostic(&d);
1174 let mut xs: Vec<Cow<'static, str>> = vec![
1175 "the compiler unexpectedly panicked. this is a bug.".into(),
1176 format!("we would appreciate a bug report: {}", bug_report_url).into(),
1178 "rustc {} running on {}",
1179 option_env!("CFG_VERSION").unwrap_or("unknown_version"),
1180 config::host_triple()
1185 if let Some((flags, excluded_cargo_defaults)) = extra_compiler_flags() {
1186 xs.push(format!("compiler flags: {}", flags.join(" ")).into());
1188 if excluded_cargo_defaults {
1189 xs.push("some of the compiler flags provided by cargo are hidden".into());
1194 handler.note_without_error(¬e);
1197 // If backtraces are enabled, also print the query stack
1198 let backtrace = env::var_os("RUST_BACKTRACE").map(|x| &x != "0").unwrap_or(false);
1201 TyCtxt::try_print_query_stack(&handler);
1206 if env::var("RUSTC_BREAK_ON_ICE").is_ok() {
1207 // Trigger a debugger if we crashed during bootstrap
1208 winapi::um::debugapi::DebugBreak();
1213 /// Installs a panic hook that will print the ICE message on unexpected panics.
1215 /// A custom rustc driver can skip calling this to set up a custom ICE hook.
1216 pub fn install_ice_hook() {
1217 lazy_static::initialize(&DEFAULT_HOOK);
1220 /// This allows tools to enable rust logging without having to magically match rustc's
1221 /// log crate version
1222 pub fn init_rustc_env_logger() {
1223 env_logger::init_from_env("RUSTC_LOG");
1227 let start = Instant::now();
1228 init_rustc_env_logger();
1229 let mut callbacks = TimePassesCallbacks::default();
1231 let result = catch_fatal_errors(|| {
1232 let args = env::args_os()
1235 arg.into_string().unwrap_or_else(|arg| {
1237 ErrorOutputType::default(),
1238 &format!("Argument {} is not valid Unicode: {:?}", i, arg),
1242 .collect::<Vec<_>>();
1243 run_compiler(&args, &mut callbacks, None, None)
1245 .and_then(|result| result);
1246 let exit_code = match result {
1247 Ok(_) => EXIT_SUCCESS,
1248 Err(_) => EXIT_FAILURE,
1250 // The extra `\t` is necessary to align this label with the others.
1251 print_time_passes_entry(callbacks.time_passes, "\ttotal", start.elapsed());
1252 process::exit(exit_code);