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_ssa::CodegenResults;
30 use rustc_codegen_utils::codegen_backend::CodegenBackend;
31 use rustc_data_structures::profiling::print_time_passes_entry;
32 use rustc_data_structures::sync::SeqCst;
33 use rustc_errors::{registry::Registry, PResult};
34 use rustc_feature::{find_gated_cfg, UnstableFeatures};
35 use rustc_hir::def_id::LOCAL_CRATE;
36 use rustc_interface::util::{collect_crate_types, get_builtin_codegen_backend};
37 use rustc_interface::{interface, Queries};
38 use rustc_lint::LintStore;
39 use rustc_metadata::locator;
40 use rustc_save_analysis as save;
41 use rustc_save_analysis::DumpHandler;
42 use rustc_serialize::json::{self, ToJson};
46 use std::default::Default;
48 use std::ffi::OsString;
50 use std::io::{self, Read, Write};
52 use std::panic::{self, catch_unwind};
53 use std::path::PathBuf;
54 use std::process::{self, Command, Stdio};
56 use std::time::Instant;
58 use rustc_span::source_map::FileLoader;
59 use rustc_span::symbol::sym;
60 use rustc_span::FileName;
66 /// Exit status code used for successful compilation and help output.
67 pub const EXIT_SUCCESS: i32 = 0;
69 /// Exit status code used for compilation failures and invalid flags.
70 pub const EXIT_FAILURE: i32 = 1;
72 const BUG_REPORT_URL: &str = "https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.\
75 const ICE_REPORT_COMPILER_FLAGS: &[&str] = &["Z", "C", "crate-type"];
77 const ICE_REPORT_COMPILER_FLAGS_EXCLUDE: &[&str] = &["metadata", "extra-filename"];
79 const ICE_REPORT_COMPILER_FLAGS_STRIP_VALUE: &[&str] = &["incremental"];
81 pub fn abort_on_err<T>(result: Result<T, ErrorReported>, sess: &Session) -> T {
84 sess.abort_if_errors();
85 panic!("error reported but abort_if_errors didn't abort???");
92 /// Called before creating the compiler instance
93 fn config(&mut self, _config: &mut interface::Config) {}
94 /// Called after parsing. Return value instructs the compiler whether to
95 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
96 fn after_parsing<'tcx>(
98 _compiler: &interface::Compiler,
99 _queries: &'tcx Queries<'tcx>,
101 Compilation::Continue
103 /// Called after expansion. Return value instructs the compiler whether to
104 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
105 fn after_expansion<'tcx>(
107 _compiler: &interface::Compiler,
108 _queries: &'tcx Queries<'tcx>,
110 Compilation::Continue
112 /// Called after analysis. Return value instructs the compiler whether to
113 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
114 fn after_analysis<'tcx>(
116 _compiler: &interface::Compiler,
117 _queries: &'tcx Queries<'tcx>,
119 Compilation::Continue
124 pub struct TimePassesCallbacks {
128 impl Callbacks for TimePassesCallbacks {
129 fn config(&mut self, config: &mut interface::Config) {
130 // If a --prints=... option has been given, we don't print the "total"
131 // time because it will mess up the --prints output. See #64339.
132 self.time_passes = config.opts.prints.is_empty()
133 && (config.opts.debugging_opts.time_passes || config.opts.debugging_opts.time);
137 pub fn diagnostics_registry() -> Registry {
138 Registry::new(&rustc_error_codes::DIAGNOSTICS)
141 // Parse args and run the compiler. This is the primary entry point for rustc.
142 // See comments on CompilerCalls below for details about the callbacks argument.
143 // The FileLoader provides a way to load files from sources other than the file system.
146 callbacks: &mut (dyn Callbacks + Send),
147 file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
148 emitter: Option<Box<dyn Write + Send>>,
149 ) -> interface::Result<()> {
150 let mut args = Vec::new();
152 match args::arg_expand(arg.clone()) {
153 Ok(arg) => args.extend(arg),
154 Err(err) => early_error(
155 ErrorOutputType::default(),
156 &format!("Failed to load argument file: {}", err),
160 let diagnostic_output =
161 emitter.map(|emitter| DiagnosticOutput::Raw(emitter)).unwrap_or(DiagnosticOutput::Default);
162 let matches = match handle_options(&args) {
163 Some(matches) => matches,
164 None => return Ok(()),
167 let sopts = config::build_session_options(&matches);
168 let cfg = interface::parse_cfgspecs(matches.opt_strs("cfg"));
170 let mut dummy_config = |sopts, cfg, diagnostic_output| {
171 let mut config = interface::Config {
174 input: Input::File(PathBuf::new()),
182 lint_caps: Default::default(),
183 register_lints: None,
184 override_queries: None,
185 registry: diagnostics_registry(),
187 callbacks.config(&mut config);
191 if let Some(ref code) = matches.opt_str("explain") {
192 handle_explain(diagnostics_registry(), code, sopts.error_format);
196 let (odir, ofile) = make_output(&matches);
197 let (input, input_file_path, input_err) = match make_input(&matches.free) {
199 None => match matches.free.len() {
201 let config = dummy_config(sopts, cfg, diagnostic_output);
202 interface::run_compiler(config, |compiler| {
203 let sopts = &compiler.session().opts;
204 if sopts.describe_lints {
205 let lint_store = rustc_lint::new_lint_store(
206 sopts.debugging_opts.no_interleave_lints,
207 compiler.session().unstable_options(),
209 describe_lints(compiler.session(), &lint_store, false);
212 let should_stop = RustcDefaultCalls::print_crate_info(
213 &***compiler.codegen_backend(),
220 if should_stop == Compilation::Stop {
223 early_error(sopts.error_format, "no input filename given")
227 1 => panic!("make_input should have provided valid inputs"),
231 "multiple input filenames provided (first two filenames are `{}` and `{}`)",
232 matches.free[0], matches.free[1],
238 if let Some(err) = input_err {
239 // Immediately stop compilation if there was an issue reading
240 // the input (for example if the input stream is not UTF-8).
241 interface::run_compiler(dummy_config(sopts, cfg, diagnostic_output), |compiler| {
242 compiler.session().err(&err.to_string());
244 return Err(ErrorReported);
247 let mut config = interface::Config {
251 input_path: input_file_path,
258 lint_caps: Default::default(),
259 register_lints: None,
260 override_queries: None,
261 registry: diagnostics_registry(),
264 callbacks.config(&mut config);
266 interface::run_compiler(config, |compiler| {
267 let sess = compiler.session();
268 let should_stop = RustcDefaultCalls::print_crate_info(
269 &***compiler.codegen_backend(),
271 Some(compiler.input()),
272 compiler.output_dir(),
273 compiler.output_file(),
276 RustcDefaultCalls::list_metadata(
278 &*compiler.codegen_backend().metadata_loader(),
283 .and_then(|| RustcDefaultCalls::try_process_rlink(sess, compiler));
285 if should_stop == Compilation::Stop {
286 return sess.compile_status();
289 let linker = compiler.enter(|queries| {
290 let early_exit = || sess.compile_status().map(|_| None);
293 if let Some(ppm) = &sess.opts.pretty {
294 if ppm.needs_ast_map() {
295 queries.global_ctxt()?.peek_mut().enter(|tcx| {
296 let expanded_crate = queries.expansion()?.take().0;
297 pretty::print_after_hir_lowering(
302 compiler.output_file().as_ref().map(|p| &**p),
307 let krate = queries.parse()?.take();
308 pretty::print_after_parsing(
313 compiler.output_file().as_ref().map(|p| &**p),
319 if callbacks.after_parsing(compiler, queries) == Compilation::Stop {
323 if sess.opts.debugging_opts.parse_only
324 || sess.opts.debugging_opts.show_span.is_some()
325 || sess.opts.debugging_opts.ast_json_noexpand
331 let (_, lint_store) = &*queries.register_plugins()?.peek();
333 // Lint plugins are registered; now we can process command line flags.
334 if sess.opts.describe_lints {
335 describe_lints(&sess, &lint_store, true);
340 queries.expansion()?;
341 if callbacks.after_expansion(compiler, queries) == Compilation::Stop {
345 queries.prepare_outputs()?;
347 if sess.opts.output_types.contains_key(&OutputType::DepInfo)
348 && sess.opts.output_types.len() == 1
353 queries.global_ctxt()?;
355 if sess.opts.debugging_opts.no_analysis || sess.opts.debugging_opts.ast_json {
359 if sess.opts.debugging_opts.save_analysis {
360 let expanded_crate = &queries.expansion()?.peek().0;
361 let crate_name = queries.crate_name()?.peek().clone();
362 queries.global_ctxt()?.peek_mut().enter(|tcx| {
363 let result = tcx.analysis(LOCAL_CRATE);
365 sess.time("save_analysis", || {
373 compiler.output_dir().as_ref().map(|p| &**p),
380 // AST will be dropped *after* the `after_analysis` callback
381 // (needed by the RLS)
384 // Drop AST after creating GlobalCtxt to free memory
385 let _timer = sess.prof.generic_activity("drop_ast");
386 mem::drop(queries.expansion()?.take());
389 queries.global_ctxt()?.peek_mut().enter(|tcx| tcx.analysis(LOCAL_CRATE))?;
391 if callbacks.after_analysis(compiler, queries) == Compilation::Stop {
395 if sess.opts.debugging_opts.save_analysis {
396 mem::drop(queries.expansion()?.take());
399 queries.ongoing_codegen()?;
401 if sess.opts.debugging_opts.print_type_sizes {
402 sess.code_stats.print_type_sizes();
405 let linker = queries.linker()?;
409 if let Some(linker) = linker {
410 let _timer = sess.timer("link");
414 if sess.opts.debugging_opts.perf_stats {
415 sess.print_perf_stats();
418 if sess.print_fuel_crate.is_some() {
420 "Fuel used by {}: {}",
421 sess.print_fuel_crate.as_ref().unwrap(),
422 sess.print_fuel.load(SeqCst)
431 pub fn set_sigpipe_handler() {
433 // Set the SIGPIPE signal handler, so that an EPIPE
434 // will cause rustc to terminate, as expected.
435 assert_ne!(libc::signal(libc::SIGPIPE, libc::SIG_DFL), libc::SIG_ERR);
440 pub fn set_sigpipe_handler() {}
442 // Extract output directory and file from matches.
443 fn make_output(matches: &getopts::Matches) -> (Option<PathBuf>, Option<PathBuf>) {
444 let odir = matches.opt_str("out-dir").map(|o| PathBuf::from(&o));
445 let ofile = matches.opt_str("o").map(|o| PathBuf::from(&o));
449 // Extract input (string or file and optional path) from matches.
450 fn make_input(free_matches: &[String]) -> Option<(Input, Option<PathBuf>, Option<io::Error>)> {
451 if free_matches.len() == 1 {
452 let ifile = &free_matches[0];
454 let mut src = String::new();
455 let err = if io::stdin().read_to_string(&mut src).is_err() {
457 io::ErrorKind::InvalidData,
458 "couldn't read from stdin, as it did not contain valid UTF-8",
463 if let Ok(path) = env::var("UNSTABLE_RUSTDOC_TEST_PATH") {
464 let line = env::var("UNSTABLE_RUSTDOC_TEST_LINE").expect(
465 "when UNSTABLE_RUSTDOC_TEST_PATH is set \
466 UNSTABLE_RUSTDOC_TEST_LINE also needs to be set",
468 let line = isize::from_str_radix(&line, 10)
469 .expect("UNSTABLE_RUSTDOC_TEST_LINE needs to be an number");
470 let file_name = FileName::doc_test_source_code(PathBuf::from(path), line);
471 return Some((Input::Str { name: file_name, input: src }, None, err));
473 Some((Input::Str { name: FileName::anon_source_code(&src), input: src }, None, err))
475 Some((Input::File(PathBuf::from(ifile)), Some(PathBuf::from(ifile)), None))
482 // Whether to stop or continue compilation.
483 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
484 pub enum Compilation {
490 pub fn and_then<F: FnOnce() -> Compilation>(self, next: F) -> Compilation {
492 Compilation::Stop => Compilation::Stop,
493 Compilation::Continue => next(),
498 /// CompilerCalls instance for a regular rustc build.
499 #[derive(Copy, Clone)]
500 pub struct RustcDefaultCalls;
502 // FIXME remove these and use winapi 0.3 instead
503 // Duplicates: bootstrap/compile.rs, librustc_errors/emitter.rs
505 fn stdout_isatty() -> bool {
506 unsafe { libc::isatty(libc::STDOUT_FILENO) != 0 }
510 fn stdout_isatty() -> bool {
511 use winapi::um::consoleapi::GetConsoleMode;
512 use winapi::um::processenv::GetStdHandle;
513 use winapi::um::winbase::STD_OUTPUT_HANDLE;
516 let handle = GetStdHandle(STD_OUTPUT_HANDLE);
518 GetConsoleMode(handle, &mut out) != 0
522 fn handle_explain(registry: Registry, code: &str, output: ErrorOutputType) {
524 if code.starts_with("E") { code.to_string() } else { format!("E{0:0>4}", code) };
525 match registry.find_description(&normalised) {
526 Some(ref description) => {
527 let mut is_in_code_block = false;
528 let mut text = String::new();
530 // Slice off the leading newline and print.
531 for line in description.lines() {
533 line.find(|c: char| !c.is_whitespace()).unwrap_or_else(|| line.len());
534 let dedented_line = &line[indent_level..];
535 if dedented_line.starts_with("```") {
536 is_in_code_block = !is_in_code_block;
537 text.push_str(&line[..(indent_level + 3)]);
538 } else if is_in_code_block && dedented_line.starts_with("# ") {
547 show_content_with_pager(&text);
553 early_error(output, &format!("no extended information for {}", code));
558 fn show_content_with_pager(content: &String) {
559 let pager_name = env::var_os("PAGER").unwrap_or_else(|| {
560 if cfg!(windows) { OsString::from("more.com") } else { OsString::from("less") }
563 let mut fallback_to_println = false;
565 match Command::new(pager_name).stdin(Stdio::piped()).spawn() {
567 if let Some(pipe) = pager.stdin.as_mut() {
568 if pipe.write_all(content.as_bytes()).is_err() {
569 fallback_to_println = true;
573 if pager.wait().is_err() {
574 fallback_to_println = true;
578 fallback_to_println = true;
582 // If pager fails for whatever reason, we should still print the content
583 // to standard output
584 if fallback_to_println {
585 print!("{}", content);
589 impl RustcDefaultCalls {
590 fn process_rlink(sess: &Session, compiler: &interface::Compiler) -> Result<(), ErrorReported> {
591 if let Input::File(file) = compiler.input() {
592 // FIXME: #![crate_type] and #![crate_name] support not implemented yet
594 sess.crate_types.set(collect_crate_types(sess, &attrs));
595 let outputs = compiler.build_output_filenames(&sess, &attrs);
596 let rlink_data = fs::read_to_string(file).unwrap_or_else(|err| {
597 sess.fatal(&format!("failed to read rlink file: {}", err));
599 let codegen_results: CodegenResults = json::decode(&rlink_data).unwrap_or_else(|err| {
600 sess.fatal(&format!("failed to decode rlink: {}", err));
602 compiler.codegen_backend().link(&sess, Box::new(codegen_results), &outputs)
604 sess.fatal(&format!("rlink must be a file"))
608 pub fn try_process_rlink(sess: &Session, compiler: &interface::Compiler) -> Compilation {
609 if sess.opts.debugging_opts.link_only {
610 let result = RustcDefaultCalls::process_rlink(sess, compiler);
611 abort_on_err(result, sess);
614 Compilation::Continue
618 pub fn list_metadata(
620 metadata_loader: &dyn MetadataLoader,
621 matches: &getopts::Matches,
624 let r = matches.opt_strs("Z");
625 if r.iter().any(|s| *s == "ls") {
627 &Input::File(ref ifile) => {
628 let path = &(*ifile);
629 let mut v = Vec::new();
630 locator::list_file_metadata(&sess.target.target, path, metadata_loader, &mut v)
632 println!("{}", String::from_utf8(v).unwrap());
634 &Input::Str { .. } => {
635 early_error(ErrorOutputType::default(), "cannot list metadata for stdin");
638 return Compilation::Stop;
641 Compilation::Continue
645 codegen_backend: &dyn CodegenBackend,
647 input: Option<&Input>,
648 odir: &Option<PathBuf>,
649 ofile: &Option<PathBuf>,
651 use rustc::session::config::PrintRequest::*;
652 // PrintRequest::NativeStaticLibs is special - printed during linking
653 // (empty iterator returns true)
654 if sess.opts.prints.iter().all(|&p| p == PrintRequest::NativeStaticLibs) {
655 return Compilation::Continue;
658 let attrs = match input {
661 let result = parse_crate_attrs(sess, input);
663 Ok(attrs) => Some(attrs),
664 Err(mut parse_error) => {
666 return Compilation::Stop;
671 for req in &sess.opts.prints {
674 let mut targets = rustc_target::spec::get_targets().collect::<Vec<String>>();
676 println!("{}", targets.join("\n"));
678 Sysroot => println!("{}", sess.sysroot.display()),
679 TargetSpec => println!("{}", sess.target.target.to_json().pretty()),
680 FileNames | CrateName => {
681 let input = input.unwrap_or_else(|| {
682 early_error(ErrorOutputType::default(), "no input file provided")
684 let attrs = attrs.as_ref().unwrap();
685 let t_outputs = rustc_interface::util::build_output_filenames(
686 input, odir, ofile, attrs, sess,
688 let id = rustc_codegen_utils::link::find_crate_name(Some(sess), attrs, input);
689 if *req == PrintRequest::CrateName {
693 let crate_types = collect_crate_types(sess, attrs);
694 for &style in &crate_types {
695 let fname = rustc_codegen_utils::link::filename_for_input(
696 sess, style, &id, &t_outputs,
698 println!("{}", fname.file_name().unwrap().to_string_lossy());
702 let allow_unstable_cfg =
703 UnstableFeatures::from_environment().is_nightly_build();
709 .filter_map(|&(name, ref value)| {
710 // Note that crt-static is a specially recognized cfg
711 // directive that's printed out here as part of
712 // rust-lang/rust#37406, but in general the
713 // `target_feature` cfg is gated under
714 // rust-lang/rust#29717. For now this is just
715 // specifically allowing the crt-static cfg and that's
716 // it, this is intended to get into Cargo and then go
717 // through to build scripts.
718 let value = value.as_ref().map(|s| s.as_str());
719 let value = value.as_ref().map(|s| s.as_ref());
720 if (name != sym::target_feature || value != Some("crt-static"))
721 && !allow_unstable_cfg
722 && find_gated_cfg(|cfg_sym| cfg_sym == name).is_some()
727 if let Some(value) = value {
728 Some(format!("{}=\"{}\"", name, value))
730 Some(name.to_string())
733 .collect::<Vec<String>>();
740 RelocationModels | CodeModels | TlsModels | TargetCPUs | TargetFeatures => {
741 codegen_backend.print(*req, sess);
743 // Any output here interferes with Cargo's parsing of other printed output
744 PrintRequest::NativeStaticLibs => {}
747 return Compilation::Stop;
751 /// Returns a version string such as "0.12.0-dev".
752 fn release_str() -> Option<&'static str> {
753 option_env!("CFG_RELEASE")
756 /// Returns the full SHA1 hash of HEAD of the Git repo from which rustc was built.
757 fn commit_hash_str() -> Option<&'static str> {
758 option_env!("CFG_VER_HASH")
761 /// Returns the "commit date" of HEAD of the Git repo from which rustc was built as a static string.
762 fn commit_date_str() -> Option<&'static str> {
763 option_env!("CFG_VER_DATE")
766 /// Prints version information
767 pub fn version(binary: &str, matches: &getopts::Matches) {
768 let verbose = matches.opt_present("verbose");
770 println!("{} {}", binary, option_env!("CFG_VERSION").unwrap_or("unknown version"));
773 fn unw(x: Option<&str>) -> &str {
774 x.unwrap_or("unknown")
776 println!("binary: {}", binary);
777 println!("commit-hash: {}", unw(commit_hash_str()));
778 println!("commit-date: {}", unw(commit_date_str()));
779 println!("host: {}", config::host_triple());
780 println!("release: {}", unw(release_str()));
781 get_builtin_codegen_backend("llvm")().print_version();
785 fn usage(verbose: bool, include_unstable_options: bool) {
786 let groups = if verbose { config::rustc_optgroups() } else { config::rustc_short_optgroups() };
787 let mut options = getopts::Options::new();
788 for option in groups.iter().filter(|x| include_unstable_options || x.is_stable()) {
789 (option.apply)(&mut options);
791 let message = "Usage: rustc [OPTIONS] INPUT";
792 let nightly_help = if nightly_options::is_nightly_build() {
793 "\n -Z help Print unstable compiler options"
797 let verbose_help = if verbose {
800 "\n --help -v Print the full set of options rustc accepts"
802 let at_path = if verbose && nightly_options::is_nightly_build() {
803 " @path Read newline separated options from `path`\n"
808 "{options}{at_path}\nAdditional help:
809 -C help Print codegen options
811 Print 'lint' options and default settings{nightly}{verbose}\n",
812 options = options.usage(message),
814 nightly = nightly_help,
815 verbose = verbose_help
819 fn print_wall_help() {
822 The flag `-Wall` does not exist in `rustc`. Most useful lints are enabled by
823 default. Use `rustc -W help` to see all available lints. It's more common to put
824 warning settings in the crate root using `#![warn(LINT_NAME)]` instead of using
825 the command line flag directly.
830 fn describe_lints(sess: &Session, lint_store: &LintStore, loaded_plugins: bool) {
833 Available lint options:
834 -W <foo> Warn about <foo>
838 -F <foo> Forbid <foo> \
839 (deny <foo> and all attempts to override)
844 fn sort_lints(sess: &Session, mut lints: Vec<&'static Lint>) -> Vec<&'static Lint> {
845 // The sort doesn't case-fold but it's doubtful we care.
846 lints.sort_by_cached_key(|x: &&Lint| (x.default_level(sess.edition()), x.name));
851 lints: Vec<(&'static str, Vec<LintId>, bool)>,
852 ) -> Vec<(&'static str, Vec<LintId>)> {
853 let mut lints: Vec<_> = lints.into_iter().map(|(x, y, _)| (x, y)).collect();
854 lints.sort_by_key(|l| l.0);
858 let (plugin, builtin): (Vec<_>, _) =
859 lint_store.get_lints().iter().cloned().partition(|&lint| lint.is_plugin);
860 let plugin = sort_lints(sess, plugin);
861 let builtin = sort_lints(sess, builtin);
863 let (plugin_groups, builtin_groups): (Vec<_>, _) =
864 lint_store.get_lint_groups().iter().cloned().partition(|&(.., p)| p);
865 let plugin_groups = sort_lint_groups(plugin_groups);
866 let builtin_groups = sort_lint_groups(builtin_groups);
869 plugin.iter().chain(&builtin).map(|&s| s.name.chars().count()).max().unwrap_or(0);
870 let padded = |x: &str| {
871 let mut s = " ".repeat(max_name_len - x.chars().count());
876 println!("Lint checks provided by rustc:\n");
877 println!(" {} {:7.7} {}", padded("name"), "default", "meaning");
878 println!(" {} {:7.7} {}", padded("----"), "-------", "-------");
880 let print_lints = |lints: Vec<&Lint>| {
882 let name = lint.name_lower().replace("_", "-");
883 println!(" {} {:7.7} {}", padded(&name), lint.default_level.as_str(), lint.desc);
888 print_lints(builtin);
890 let max_name_len = max(
894 .chain(&builtin_groups)
895 .map(|&(s, _)| s.chars().count())
900 let padded = |x: &str| {
901 let mut s = " ".repeat(max_name_len - x.chars().count());
906 println!("Lint groups provided by rustc:\n");
907 println!(" {} {}", padded("name"), "sub-lints");
908 println!(" {} {}", padded("----"), "---------");
909 println!(" {} {}", padded("warnings"), "all lints that are set to issue warnings");
911 let print_lint_groups = |lints: Vec<(&'static str, Vec<LintId>)>| {
912 for (name, to) in lints {
913 let name = name.to_lowercase().replace("_", "-");
916 .map(|x| x.to_string().replace("_", "-"))
917 .collect::<Vec<String>>()
919 println!(" {} {}", padded(&name), desc);
924 print_lint_groups(builtin_groups);
926 match (loaded_plugins, plugin.len(), plugin_groups.len()) {
927 (false, 0, _) | (false, _, 0) => {
929 "Compiler plugins can provide additional lints and lint groups. To see a \
930 listing of these, re-run `rustc -W help` with a crate filename."
933 (false, ..) => panic!("didn't load lint plugins but got them anyway!"),
934 (true, 0, 0) => println!("This crate does not load any lint plugins or lint groups."),
937 println!("Lint checks provided by plugins loaded by this crate:\n");
941 println!("Lint groups provided by plugins loaded by this crate:\n");
942 print_lint_groups(plugin_groups);
948 fn describe_debug_flags() {
949 println!("\nAvailable options:\n");
950 print_flag_list("-Z", config::DB_OPTIONS);
953 fn describe_codegen_flags() {
954 println!("\nAvailable codegen options:\n");
955 print_flag_list("-C", config::CG_OPTIONS);
958 fn print_flag_list<T>(
960 flag_list: &[(&'static str, T, Option<&'static str>, &'static str)],
962 let max_len = flag_list
964 .map(|&(name, _, opt_type_desc, _)| {
965 let extra_len = match opt_type_desc {
969 name.chars().count() + extra_len
974 for &(name, _, opt_type_desc, desc) in flag_list {
975 let (width, extra) = match opt_type_desc {
976 Some(..) => (max_len - 4, "=val"),
977 None => (max_len, ""),
980 " {} {:>width$}{} -- {}",
982 name.replace("_", "-"),
990 /// Process command line options. Emits messages as appropriate. If compilation
991 /// should continue, returns a getopts::Matches object parsed from args,
992 /// otherwise returns `None`.
994 /// The compiler's handling of options is a little complicated as it ties into
995 /// our stability story. The current intention of each compiler option is to
996 /// have one of two modes:
998 /// 1. An option is stable and can be used everywhere.
999 /// 2. An option is unstable, and can only be used on nightly.
1001 /// Like unstable library and language features, however, unstable options have
1002 /// always required a form of "opt in" to indicate that you're using them. This
1003 /// provides the easy ability to scan a code base to check to see if anything
1004 /// unstable is being used. Currently, this "opt in" is the `-Z` "zed" flag.
1006 /// All options behind `-Z` are considered unstable by default. Other top-level
1007 /// options can also be considered unstable, and they were unlocked through the
1008 /// `-Z unstable-options` flag. Note that `-Z` remains to be the root of
1009 /// instability in both cases, though.
1011 /// So with all that in mind, the comments below have some more detail about the
1012 /// contortions done here to get things to work out correctly.
1013 pub fn handle_options(args: &[String]) -> Option<getopts::Matches> {
1014 // Throw away the first argument, the name of the binary
1015 let args = &args[1..];
1017 if args.is_empty() {
1018 // user did not write `-v` nor `-Z unstable-options`, so do not
1019 // include that extra information.
1020 usage(false, false);
1024 // Parse with *all* options defined in the compiler, we don't worry about
1025 // option stability here we just want to parse as much as possible.
1026 let mut options = getopts::Options::new();
1027 for option in config::rustc_optgroups() {
1028 (option.apply)(&mut options);
1030 let matches = options
1032 .unwrap_or_else(|f| early_error(ErrorOutputType::default(), &f.to_string()));
1034 // For all options we just parsed, we check a few aspects:
1036 // * If the option is stable, we're all good
1037 // * If the option wasn't passed, we're all good
1038 // * If `-Z unstable-options` wasn't passed (and we're not a -Z option
1039 // ourselves), then we require the `-Z unstable-options` flag to unlock
1040 // this option that was passed.
1041 // * If we're a nightly compiler, then unstable options are now unlocked, so
1042 // we're good to go.
1043 // * Otherwise, if we're an unstable option then we generate an error
1044 // (unstable option being used on stable)
1045 nightly_options::check_nightly_options(&matches, &config::rustc_optgroups());
1047 if matches.opt_present("h") || matches.opt_present("help") {
1048 // Only show unstable options in --help if we accept unstable options.
1049 usage(matches.opt_present("verbose"), nightly_options::is_unstable_enabled(&matches));
1053 // Handle the special case of -Wall.
1054 let wall = matches.opt_strs("W");
1055 if wall.iter().any(|x| *x == "all") {
1060 // Don't handle -W help here, because we might first load plugins.
1061 let r = matches.opt_strs("Z");
1062 if r.iter().any(|x| *x == "help") {
1063 describe_debug_flags();
1067 let cg_flags = matches.opt_strs("C");
1069 if cg_flags.iter().any(|x| *x == "help") {
1070 describe_codegen_flags();
1074 if cg_flags.iter().any(|x| *x == "no-stack-check") {
1076 ErrorOutputType::default(),
1077 "the --no-stack-check flag is deprecated and does nothing",
1081 if cg_flags.iter().any(|x| *x == "passes=list") {
1082 get_builtin_codegen_backend("llvm")().print_passes();
1086 if matches.opt_present("version") {
1087 version("rustc", &matches);
1094 fn parse_crate_attrs<'a>(sess: &'a Session, input: &Input) -> PResult<'a, Vec<ast::Attribute>> {
1096 Input::File(ifile) => rustc_parse::parse_crate_attrs_from_file(ifile, &sess.parse_sess),
1097 Input::Str { name, input } => rustc_parse::parse_crate_attrs_from_source_str(
1105 /// Gets a list of extra command-line flags provided by the user, as strings.
1107 /// This function is used during ICEs to show more information useful for
1108 /// debugging, since some ICEs only happens with non-default compiler flags
1109 /// (and the users don't always report them).
1110 fn extra_compiler_flags() -> Option<(Vec<String>, bool)> {
1111 let args = env::args_os().map(|arg| arg.to_string_lossy().to_string()).collect::<Vec<_>>();
1113 // Avoid printing help because of empty args. This can suggest the compiler
1114 // itself is not the program root (consider RLS).
1119 let matches = if let Some(matches) = handle_options(&args) {
1125 let mut result = Vec::new();
1126 let mut excluded_cargo_defaults = false;
1127 for flag in ICE_REPORT_COMPILER_FLAGS {
1128 let prefix = if flag.len() == 1 { "-" } else { "--" };
1130 for content in &matches.opt_strs(flag) {
1131 // Split always returns the first element
1132 let name = if let Some(first) = content.split('=').next() { first } else { &content };
1135 if ICE_REPORT_COMPILER_FLAGS_STRIP_VALUE.contains(&name) { name } else { content };
1137 if !ICE_REPORT_COMPILER_FLAGS_EXCLUDE.contains(&name) {
1138 result.push(format!("{}{} {}", prefix, flag, content));
1140 excluded_cargo_defaults = true;
1145 if !result.is_empty() { Some((result, excluded_cargo_defaults)) } else { None }
1148 /// Runs a closure and catches unwinds triggered by fatal errors.
1150 /// The compiler currently unwinds with a special sentinel value to abort
1151 /// compilation on fatal errors. This function catches that sentinel and turns
1152 /// the panic into a `Result` instead.
1153 pub fn catch_fatal_errors<F: FnOnce() -> R, R>(f: F) -> Result<R, ErrorReported> {
1154 catch_unwind(panic::AssertUnwindSafe(f)).map_err(|value| {
1155 if value.is::<rustc_errors::FatalErrorMarker>() {
1158 panic::resume_unwind(value);
1164 static ref DEFAULT_HOOK: Box<dyn Fn(&panic::PanicInfo<'_>) + Sync + Send + 'static> = {
1165 let hook = panic::take_hook();
1166 panic::set_hook(Box::new(|info| report_ice(info, BUG_REPORT_URL)));
1171 /// Prints the ICE message, including backtrace and query stack.
1173 /// The message will point the user at `bug_report_url` to report the ICE.
1175 /// When `install_ice_hook` is called, this function will be called as the panic
1177 pub fn report_ice(info: &panic::PanicInfo<'_>, bug_report_url: &str) {
1178 // Invoke the default handler, which prints the actual panic message and optionally a backtrace
1179 (*DEFAULT_HOOK)(info);
1181 // Separate the output with an empty line
1184 let emitter = Box::new(rustc_errors::emitter::EmitterWriter::stderr(
1185 rustc_errors::ColorConfig::Auto,
1192 let handler = rustc_errors::Handler::with_emitter(true, None, emitter);
1194 // a .span_bug or .bug call has already printed what
1195 // it wants to print.
1196 if !info.payload().is::<rustc_errors::ExplicitBug>() {
1197 let d = rustc_errors::Diagnostic::new(rustc_errors::Level::Bug, "unexpected panic");
1198 handler.emit_diagnostic(&d);
1201 let mut xs: Vec<Cow<'static, str>> = vec![
1202 "the compiler unexpectedly panicked. this is a bug.".into(),
1203 format!("we would appreciate a bug report: {}", bug_report_url).into(),
1205 "rustc {} running on {}",
1206 option_env!("CFG_VERSION").unwrap_or("unknown_version"),
1207 config::host_triple()
1212 if let Some((flags, excluded_cargo_defaults)) = extra_compiler_flags() {
1213 xs.push(format!("compiler flags: {}", flags.join(" ")).into());
1215 if excluded_cargo_defaults {
1216 xs.push("some of the compiler flags provided by cargo are hidden".into());
1221 handler.note_without_error(¬e);
1224 // If backtraces are enabled, also print the query stack
1225 let backtrace = env::var_os("RUST_BACKTRACE").map(|x| &x != "0").unwrap_or(false);
1228 TyCtxt::try_print_query_stack(&handler);
1233 if env::var("RUSTC_BREAK_ON_ICE").is_ok() {
1234 // Trigger a debugger if we crashed during bootstrap
1235 winapi::um::debugapi::DebugBreak();
1240 /// Installs a panic hook that will print the ICE message on unexpected panics.
1242 /// A custom rustc driver can skip calling this to set up a custom ICE hook.
1243 pub fn install_ice_hook() {
1244 lazy_static::initialize(&DEFAULT_HOOK);
1247 /// This allows tools to enable rust logging without having to magically match rustc's
1248 /// log crate version
1249 pub fn init_rustc_env_logger() {
1250 env_logger::init_from_env("RUSTC_LOG");
1254 let start = Instant::now();
1255 init_rustc_env_logger();
1256 let mut callbacks = TimePassesCallbacks::default();
1258 let result = catch_fatal_errors(|| {
1259 let args = env::args_os()
1262 arg.into_string().unwrap_or_else(|arg| {
1264 ErrorOutputType::default(),
1265 &format!("Argument {} is not valid Unicode: {:?}", i, arg),
1269 .collect::<Vec<_>>();
1270 run_compiler(&args, &mut callbacks, None, None)
1272 .and_then(|result| result);
1273 let exit_code = match result {
1274 Ok(_) => EXIT_SUCCESS,
1275 Err(_) => EXIT_FAILURE,
1277 // The extra `\t` is necessary to align this label with the others.
1278 print_time_passes_entry(callbacks.time_passes, "\ttotal", start.elapsed());
1279 process::exit(exit_code);