5 //! This API is completely unstable and subject to change.
7 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/")]
8 #![feature(box_syntax)]
9 #![cfg_attr(unix, feature(libc))]
11 #![feature(set_stdio)]
13 #![feature(integer_atomics)]
14 #![recursion_limit = "256"]
16 pub extern crate getopts;
22 extern crate lazy_static;
24 pub extern crate rustc_plugin_impl as plugin;
26 //use rustc_resolve as resolve;
28 use rustc::lint::Lint;
29 use rustc::middle::cstore::MetadataLoader;
30 use rustc::session::config::nightly_options;
31 use rustc::session::config::{ErrorOutputType, Input, OutputType, PrintRequest};
32 use rustc::session::{config, DiagnosticOutput, Session};
33 use rustc::session::{early_error, early_warn};
34 use rustc::ty::TyCtxt;
35 use rustc::util::common::ErrorReported;
36 use rustc_codegen_utils::codegen_backend::CodegenBackend;
37 use rustc_data_structures::profiling::print_time_passes_entry;
38 use rustc_data_structures::sync::SeqCst;
39 use rustc_errors::{registry::Registry, PResult};
40 use rustc_feature::{find_gated_cfg, UnstableFeatures};
41 use rustc_hir::def_id::LOCAL_CRATE;
42 use rustc_interface::util::get_builtin_codegen_backend;
43 use rustc_interface::{interface, Queries};
44 use rustc_metadata::locator;
45 use rustc_save_analysis as save;
46 use rustc_save_analysis::DumpHandler;
47 use rustc_serialize::json::ToJson;
51 use std::default::Default;
53 use std::ffi::OsString;
54 use std::io::{self, Read, Write};
56 use std::panic::{self, catch_unwind};
57 use std::path::PathBuf;
58 use std::process::{self, Command, Stdio};
60 use std::time::Instant;
62 use rustc_span::source_map::FileLoader;
63 use rustc_span::symbol::sym;
64 use rustc_span::FileName;
70 /// Exit status code used for successful compilation and help output.
71 pub const EXIT_SUCCESS: i32 = 0;
73 /// Exit status code used for compilation failures and invalid flags.
74 pub const EXIT_FAILURE: i32 = 1;
76 const BUG_REPORT_URL: &str = "https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.\
79 const ICE_REPORT_COMPILER_FLAGS: &[&str] = &["Z", "C", "crate-type"];
81 const ICE_REPORT_COMPILER_FLAGS_EXCLUDE: &[&str] = &["metadata", "extra-filename"];
83 const ICE_REPORT_COMPILER_FLAGS_STRIP_VALUE: &[&str] = &["incremental"];
85 pub fn abort_on_err<T>(result: Result<T, ErrorReported>, sess: &Session) -> T {
88 sess.abort_if_errors();
89 panic!("error reported but abort_if_errors didn't abort???");
96 /// Called before creating the compiler instance
97 fn config(&mut self, _config: &mut interface::Config) {}
98 /// Called after parsing. Return value instructs the compiler whether to
99 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
100 fn after_parsing<'tcx>(
102 _compiler: &interface::Compiler,
103 _queries: &'tcx Queries<'tcx>,
105 Compilation::Continue
107 /// Called after expansion. Return value instructs the compiler whether to
108 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
109 fn after_expansion<'tcx>(
111 _compiler: &interface::Compiler,
112 _queries: &'tcx Queries<'tcx>,
114 Compilation::Continue
116 /// Called after analysis. Return value instructs the compiler whether to
117 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
118 fn after_analysis<'tcx>(
120 _compiler: &interface::Compiler,
121 _queries: &'tcx Queries<'tcx>,
123 Compilation::Continue
127 pub struct DefaultCallbacks;
129 impl Callbacks for DefaultCallbacks {}
132 pub struct TimePassesCallbacks {
136 impl Callbacks for TimePassesCallbacks {
137 fn config(&mut self, config: &mut interface::Config) {
138 // If a --prints=... option has been given, we don't print the "total"
139 // time because it will mess up the --prints output. See #64339.
140 self.time_passes = config.opts.prints.is_empty()
141 && (config.opts.debugging_opts.time_passes || config.opts.debugging_opts.time);
145 pub fn diagnostics_registry() -> Registry {
146 Registry::new(&rustc_error_codes::DIAGNOSTICS)
149 // Parse args and run the compiler. This is the primary entry point for rustc.
150 // See comments on CompilerCalls below for details about the callbacks argument.
151 // The FileLoader provides a way to load files from sources other than the file system.
154 callbacks: &mut (dyn Callbacks + Send),
155 file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
156 emitter: Option<Box<dyn Write + Send>>,
157 ) -> interface::Result<()> {
158 let mut args = Vec::new();
160 match args::arg_expand(arg.clone()) {
161 Ok(arg) => args.extend(arg),
162 Err(err) => early_error(
163 ErrorOutputType::default(),
164 &format!("Failed to load argument file: {}", err),
168 let diagnostic_output =
169 emitter.map(|emitter| DiagnosticOutput::Raw(emitter)).unwrap_or(DiagnosticOutput::Default);
170 let matches = match handle_options(&args) {
171 Some(matches) => matches,
172 None => return Ok(()),
175 let sopts = config::build_session_options(&matches);
176 let cfg = interface::parse_cfgspecs(matches.opt_strs("cfg"));
178 let mut dummy_config = |sopts, cfg, diagnostic_output| {
179 let mut config = interface::Config {
182 input: Input::File(PathBuf::new()),
190 lint_caps: Default::default(),
191 register_lints: None,
192 override_queries: None,
193 registry: diagnostics_registry(),
195 callbacks.config(&mut config);
199 if let Some(ref code) = matches.opt_str("explain") {
200 handle_explain(diagnostics_registry(), code, sopts.error_format);
204 let (odir, ofile) = make_output(&matches);
205 let (input, input_file_path, input_err) = match make_input(&matches.free) {
207 None => match matches.free.len() {
209 let config = dummy_config(sopts, cfg, diagnostic_output);
210 interface::run_compiler(config, |compiler| {
211 let sopts = &compiler.session().opts;
212 if sopts.describe_lints {
213 let lint_store = rustc_lint::new_lint_store(
214 sopts.debugging_opts.no_interleave_lints,
215 compiler.session().unstable_options(),
217 describe_lints(compiler.session(), &lint_store, false);
220 let should_stop = RustcDefaultCalls::print_crate_info(
221 &***compiler.codegen_backend(),
228 if should_stop == Compilation::Stop {
231 early_error(sopts.error_format, "no input filename given")
235 1 => panic!("make_input should have provided valid inputs"),
239 "multiple input filenames provided (first two filenames are `{}` and `{}`)",
240 matches.free[0], matches.free[1],
246 if let Some(err) = input_err {
247 // Immediately stop compilation if there was an issue reading
248 // the input (for example if the input stream is not UTF-8).
249 interface::run_compiler(dummy_config(sopts, cfg, diagnostic_output), |compiler| {
250 compiler.session().err(&err.to_string());
252 return Err(ErrorReported);
255 let mut config = interface::Config {
259 input_path: input_file_path,
266 lint_caps: Default::default(),
267 register_lints: None,
268 override_queries: None,
269 registry: diagnostics_registry(),
272 callbacks.config(&mut config);
274 interface::run_compiler(config, |compiler| {
275 let sess = compiler.session();
276 let should_stop = RustcDefaultCalls::print_crate_info(
277 &***compiler.codegen_backend(),
279 Some(compiler.input()),
280 compiler.output_dir(),
281 compiler.output_file(),
284 RustcDefaultCalls::list_metadata(
286 &*compiler.codegen_backend().metadata_loader(),
292 if should_stop == Compilation::Stop {
293 return sess.compile_status();
296 let linker = compiler.enter(|queries| {
297 let early_exit = || sess.compile_status().map(|_| None);
300 if let Some(ppm) = &sess.opts.pretty {
301 if ppm.needs_ast_map() {
302 queries.global_ctxt()?.peek_mut().enter(|tcx| {
303 let expanded_crate = queries.expansion()?.take().0;
304 pretty::print_after_hir_lowering(
309 compiler.output_file().as_ref().map(|p| &**p),
314 let krate = queries.parse()?.take();
315 pretty::print_after_parsing(
320 compiler.output_file().as_ref().map(|p| &**p),
326 if callbacks.after_parsing(compiler, queries) == Compilation::Stop {
330 if sess.opts.debugging_opts.parse_only
331 || sess.opts.debugging_opts.show_span.is_some()
332 || sess.opts.debugging_opts.ast_json_noexpand
338 let (_, lint_store) = &*queries.register_plugins()?.peek();
340 // Lint plugins are registered; now we can process command line flags.
341 if sess.opts.describe_lints {
342 describe_lints(&sess, &lint_store, true);
347 queries.expansion()?;
348 if callbacks.after_expansion(compiler, queries) == Compilation::Stop {
352 queries.prepare_outputs()?;
354 if sess.opts.output_types.contains_key(&OutputType::DepInfo)
355 && sess.opts.output_types.len() == 1
360 queries.global_ctxt()?;
362 if sess.opts.debugging_opts.no_analysis || sess.opts.debugging_opts.ast_json {
366 if sess.opts.debugging_opts.save_analysis {
367 let expanded_crate = &queries.expansion()?.peek().0;
368 let crate_name = queries.crate_name()?.peek().clone();
369 queries.global_ctxt()?.peek_mut().enter(|tcx| {
370 let result = tcx.analysis(LOCAL_CRATE);
372 sess.time("save_analysis", || {
380 compiler.output_dir().as_ref().map(|p| &**p),
387 // AST will be dropped *after* the `after_analysis` callback
388 // (needed by the RLS)
391 // Drop AST after creating GlobalCtxt to free memory
392 let _timer = sess.prof.generic_activity("drop_ast");
393 mem::drop(queries.expansion()?.take());
396 queries.global_ctxt()?.peek_mut().enter(|tcx| tcx.analysis(LOCAL_CRATE))?;
398 if callbacks.after_analysis(compiler, queries) == Compilation::Stop {
402 if sess.opts.debugging_opts.save_analysis {
403 mem::drop(queries.expansion()?.take());
406 queries.ongoing_codegen()?;
408 if sess.opts.debugging_opts.print_type_sizes {
409 sess.code_stats.print_type_sizes();
412 let linker = queries.linker()?;
416 if let Some(linker) = linker {
417 let _timer = sess.timer("link");
421 if sess.opts.debugging_opts.perf_stats {
422 sess.print_perf_stats();
425 if sess.print_fuel_crate.is_some() {
427 "Fuel used by {}: {}",
428 sess.print_fuel_crate.as_ref().unwrap(),
429 sess.print_fuel.load(SeqCst)
438 pub fn set_sigpipe_handler() {
440 // Set the SIGPIPE signal handler, so that an EPIPE
441 // will cause rustc to terminate, as expected.
442 assert_ne!(libc::signal(libc::SIGPIPE, libc::SIG_DFL), libc::SIG_ERR);
447 pub fn set_sigpipe_handler() {}
449 // Extract output directory and file from matches.
450 fn make_output(matches: &getopts::Matches) -> (Option<PathBuf>, Option<PathBuf>) {
451 let odir = matches.opt_str("out-dir").map(|o| PathBuf::from(&o));
452 let ofile = matches.opt_str("o").map(|o| PathBuf::from(&o));
456 // Extract input (string or file and optional path) from matches.
457 fn make_input(free_matches: &[String]) -> Option<(Input, Option<PathBuf>, Option<io::Error>)> {
458 if free_matches.len() == 1 {
459 let ifile = &free_matches[0];
461 let mut src = String::new();
462 let err = if io::stdin().read_to_string(&mut src).is_err() {
464 io::ErrorKind::InvalidData,
465 "couldn't read from stdin, as it did not contain valid UTF-8",
470 if let Ok(path) = env::var("UNSTABLE_RUSTDOC_TEST_PATH") {
471 let line = env::var("UNSTABLE_RUSTDOC_TEST_LINE").expect(
472 "when UNSTABLE_RUSTDOC_TEST_PATH is set \
473 UNSTABLE_RUSTDOC_TEST_LINE also needs to be set",
475 let line = isize::from_str_radix(&line, 10)
476 .expect("UNSTABLE_RUSTDOC_TEST_LINE needs to be an number");
477 let file_name = FileName::doc_test_source_code(PathBuf::from(path), line);
478 return Some((Input::Str { name: file_name, input: src }, None, err));
480 Some((Input::Str { name: FileName::anon_source_code(&src), input: src }, None, err))
482 Some((Input::File(PathBuf::from(ifile)), Some(PathBuf::from(ifile)), None))
489 // Whether to stop or continue compilation.
490 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
491 pub enum Compilation {
497 pub fn and_then<F: FnOnce() -> Compilation>(self, next: F) -> Compilation {
499 Compilation::Stop => Compilation::Stop,
500 Compilation::Continue => next(),
505 /// CompilerCalls instance for a regular rustc build.
506 #[derive(Copy, Clone)]
507 pub struct RustcDefaultCalls;
509 // FIXME remove these and use winapi 0.3 instead
510 // Duplicates: bootstrap/compile.rs, librustc_errors/emitter.rs
512 fn stdout_isatty() -> bool {
513 unsafe { libc::isatty(libc::STDOUT_FILENO) != 0 }
517 fn stdout_isatty() -> bool {
520 type HANDLE = *mut u8;
521 type LPDWORD = *mut u32;
522 const STD_OUTPUT_HANDLE: DWORD = -11i32 as DWORD;
524 fn GetStdHandle(which: DWORD) -> HANDLE;
525 fn GetConsoleMode(hConsoleHandle: HANDLE, lpMode: LPDWORD) -> BOOL;
528 let handle = GetStdHandle(STD_OUTPUT_HANDLE);
530 GetConsoleMode(handle, &mut out) != 0
534 fn handle_explain(registry: Registry, code: &str, output: ErrorOutputType) {
536 if code.starts_with("E") { code.to_string() } else { format!("E{0:0>4}", code) };
537 match registry.find_description(&normalised) {
538 Some(ref description) => {
539 let mut is_in_code_block = false;
540 let mut text = String::new();
542 // Slice off the leading newline and print.
543 for line in description.lines() {
545 line.find(|c: char| !c.is_whitespace()).unwrap_or_else(|| line.len());
546 let dedented_line = &line[indent_level..];
547 if dedented_line.starts_with("```") {
548 is_in_code_block = !is_in_code_block;
549 text.push_str(&line[..(indent_level + 3)]);
550 } else if is_in_code_block && dedented_line.starts_with("# ") {
559 show_content_with_pager(&text);
565 early_error(output, &format!("no extended information for {}", code));
570 fn show_content_with_pager(content: &String) {
571 let pager_name = env::var_os("PAGER").unwrap_or_else(|| {
572 if cfg!(windows) { OsString::from("more.com") } else { OsString::from("less") }
575 let mut fallback_to_println = false;
577 match Command::new(pager_name).stdin(Stdio::piped()).spawn() {
579 if let Some(pipe) = pager.stdin.as_mut() {
580 if pipe.write_all(content.as_bytes()).is_err() {
581 fallback_to_println = true;
585 if pager.wait().is_err() {
586 fallback_to_println = true;
590 fallback_to_println = true;
594 // If pager fails for whatever reason, we should still print the content
595 // to standard output
596 if fallback_to_println {
597 print!("{}", content);
601 impl RustcDefaultCalls {
602 pub fn list_metadata(
604 metadata_loader: &dyn MetadataLoader,
605 matches: &getopts::Matches,
608 let r = matches.opt_strs("Z");
609 if r.iter().any(|s| *s == "ls") {
611 &Input::File(ref ifile) => {
612 let path = &(*ifile);
613 let mut v = Vec::new();
614 locator::list_file_metadata(&sess.target.target, path, metadata_loader, &mut v)
616 println!("{}", String::from_utf8(v).unwrap());
618 &Input::Str { .. } => {
619 early_error(ErrorOutputType::default(), "cannot list metadata for stdin");
622 return Compilation::Stop;
625 Compilation::Continue
629 codegen_backend: &dyn CodegenBackend,
631 input: Option<&Input>,
632 odir: &Option<PathBuf>,
633 ofile: &Option<PathBuf>,
635 use rustc::session::config::PrintRequest::*;
636 // PrintRequest::NativeStaticLibs is special - printed during linking
637 // (empty iterator returns true)
638 if sess.opts.prints.iter().all(|&p| p == PrintRequest::NativeStaticLibs) {
639 return Compilation::Continue;
642 let attrs = match input {
645 let result = parse_crate_attrs(sess, input);
647 Ok(attrs) => Some(attrs),
648 Err(mut parse_error) => {
650 return Compilation::Stop;
655 for req in &sess.opts.prints {
658 let mut targets = rustc_target::spec::get_targets().collect::<Vec<String>>();
660 println!("{}", targets.join("\n"));
662 Sysroot => println!("{}", sess.sysroot.display()),
663 TargetSpec => println!("{}", sess.target.target.to_json().pretty()),
664 FileNames | CrateName => {
665 let input = input.unwrap_or_else(|| {
666 early_error(ErrorOutputType::default(), "no input file provided")
668 let attrs = attrs.as_ref().unwrap();
669 let t_outputs = rustc_interface::util::build_output_filenames(
670 input, odir, ofile, attrs, sess,
672 let id = rustc_codegen_utils::link::find_crate_name(Some(sess), attrs, input);
673 if *req == PrintRequest::CrateName {
677 let crate_types = rustc_interface::util::collect_crate_types(sess, attrs);
678 for &style in &crate_types {
679 let fname = rustc_codegen_utils::link::filename_for_input(
680 sess, style, &id, &t_outputs,
682 println!("{}", fname.file_name().unwrap().to_string_lossy());
686 let allow_unstable_cfg =
687 UnstableFeatures::from_environment().is_nightly_build();
693 .filter_map(|&(name, ref value)| {
694 // Note that crt-static is a specially recognized cfg
695 // directive that's printed out here as part of
696 // rust-lang/rust#37406, but in general the
697 // `target_feature` cfg is gated under
698 // rust-lang/rust#29717. For now this is just
699 // specifically allowing the crt-static cfg and that's
700 // it, this is intended to get into Cargo and then go
701 // through to build scripts.
702 let value = value.as_ref().map(|s| s.as_str());
703 let value = value.as_ref().map(|s| s.as_ref());
704 if (name != sym::target_feature || value != Some("crt-static"))
705 && !allow_unstable_cfg
706 && find_gated_cfg(|cfg_sym| cfg_sym == name).is_some()
711 if let Some(value) = value {
712 Some(format!("{}=\"{}\"", name, value))
714 Some(name.to_string())
717 .collect::<Vec<String>>();
724 RelocationModels | CodeModels | TlsModels | TargetCPUs | TargetFeatures => {
725 codegen_backend.print(*req, sess);
727 // Any output here interferes with Cargo's parsing of other printed output
728 PrintRequest::NativeStaticLibs => {}
731 return Compilation::Stop;
735 /// Returns a version string such as "0.12.0-dev".
736 fn release_str() -> Option<&'static str> {
737 option_env!("CFG_RELEASE")
740 /// Returns the full SHA1 hash of HEAD of the Git repo from which rustc was built.
741 fn commit_hash_str() -> Option<&'static str> {
742 option_env!("CFG_VER_HASH")
745 /// Returns the "commit date" of HEAD of the Git repo from which rustc was built as a static string.
746 fn commit_date_str() -> Option<&'static str> {
747 option_env!("CFG_VER_DATE")
750 /// Prints version information
751 pub fn version(binary: &str, matches: &getopts::Matches) {
752 let verbose = matches.opt_present("verbose");
754 println!("{} {}", binary, option_env!("CFG_VERSION").unwrap_or("unknown version"));
757 fn unw(x: Option<&str>) -> &str {
758 x.unwrap_or("unknown")
760 println!("binary: {}", binary);
761 println!("commit-hash: {}", unw(commit_hash_str()));
762 println!("commit-date: {}", unw(commit_date_str()));
763 println!("host: {}", config::host_triple());
764 println!("release: {}", unw(release_str()));
765 get_builtin_codegen_backend("llvm")().print_version();
769 fn usage(verbose: bool, include_unstable_options: bool) {
770 let groups = if verbose { config::rustc_optgroups() } else { config::rustc_short_optgroups() };
771 let mut options = getopts::Options::new();
772 for option in groups.iter().filter(|x| include_unstable_options || x.is_stable()) {
773 (option.apply)(&mut options);
775 let message = "Usage: rustc [OPTIONS] INPUT";
776 let nightly_help = if nightly_options::is_nightly_build() {
777 "\n -Z help Print unstable compiler options"
781 let verbose_help = if verbose {
784 "\n --help -v Print the full set of options rustc accepts"
786 let at_path = if verbose && nightly_options::is_nightly_build() {
787 " @path Read newline separated options from `path`\n"
792 "{options}{at_path}\nAdditional help:
793 -C help Print codegen options
795 Print 'lint' options and default settings{nightly}{verbose}\n",
796 options = options.usage(message),
798 nightly = nightly_help,
799 verbose = verbose_help
803 fn print_wall_help() {
806 The flag `-Wall` does not exist in `rustc`. Most useful lints are enabled by
807 default. Use `rustc -W help` to see all available lints. It's more common to put
808 warning settings in the crate root using `#![warn(LINT_NAME)]` instead of using
809 the command line flag directly.
814 fn describe_lints(sess: &Session, lint_store: &lint::LintStore, loaded_plugins: bool) {
817 Available lint options:
818 -W <foo> Warn about <foo>
822 -F <foo> Forbid <foo> \
823 (deny <foo> and all attempts to override)
828 fn sort_lints(sess: &Session, mut lints: Vec<&'static Lint>) -> Vec<&'static Lint> {
829 // The sort doesn't case-fold but it's doubtful we care.
830 lints.sort_by_cached_key(|x: &&Lint| (x.default_level(sess.edition()), x.name));
835 lints: Vec<(&'static str, Vec<lint::LintId>, bool)>,
836 ) -> Vec<(&'static str, Vec<lint::LintId>)> {
837 let mut lints: Vec<_> = lints.into_iter().map(|(x, y, _)| (x, y)).collect();
838 lints.sort_by_key(|l| l.0);
842 let (plugin, builtin): (Vec<_>, _) =
843 lint_store.get_lints().iter().cloned().partition(|&lint| lint.is_plugin);
844 let plugin = sort_lints(sess, plugin);
845 let builtin = sort_lints(sess, builtin);
847 let (plugin_groups, builtin_groups): (Vec<_>, _) =
848 lint_store.get_lint_groups().iter().cloned().partition(|&(.., p)| p);
849 let plugin_groups = sort_lint_groups(plugin_groups);
850 let builtin_groups = sort_lint_groups(builtin_groups);
853 plugin.iter().chain(&builtin).map(|&s| s.name.chars().count()).max().unwrap_or(0);
854 let padded = |x: &str| {
855 let mut s = " ".repeat(max_name_len - x.chars().count());
860 println!("Lint checks provided by rustc:\n");
861 println!(" {} {:7.7} {}", padded("name"), "default", "meaning");
862 println!(" {} {:7.7} {}", padded("----"), "-------", "-------");
864 let print_lints = |lints: Vec<&Lint>| {
866 let name = lint.name_lower().replace("_", "-");
867 println!(" {} {:7.7} {}", padded(&name), lint.default_level.as_str(), lint.desc);
872 print_lints(builtin);
874 let max_name_len = max(
878 .chain(&builtin_groups)
879 .map(|&(s, _)| s.chars().count())
884 let padded = |x: &str| {
885 let mut s = " ".repeat(max_name_len - x.chars().count());
890 println!("Lint groups provided by rustc:\n");
891 println!(" {} {}", padded("name"), "sub-lints");
892 println!(" {} {}", padded("----"), "---------");
893 println!(" {} {}", padded("warnings"), "all lints that are set to issue warnings");
895 let print_lint_groups = |lints: Vec<(&'static str, Vec<lint::LintId>)>| {
896 for (name, to) in lints {
897 let name = name.to_lowercase().replace("_", "-");
900 .map(|x| x.to_string().replace("_", "-"))
901 .collect::<Vec<String>>()
903 println!(" {} {}", padded(&name), desc);
908 print_lint_groups(builtin_groups);
910 match (loaded_plugins, plugin.len(), plugin_groups.len()) {
911 (false, 0, _) | (false, _, 0) => {
913 "Compiler plugins can provide additional lints and lint groups. To see a \
914 listing of these, re-run `rustc -W help` with a crate filename."
917 (false, ..) => panic!("didn't load lint plugins but got them anyway!"),
918 (true, 0, 0) => println!("This crate does not load any lint plugins or lint groups."),
921 println!("Lint checks provided by plugins loaded by this crate:\n");
925 println!("Lint groups provided by plugins loaded by this crate:\n");
926 print_lint_groups(plugin_groups);
932 fn describe_debug_flags() {
933 println!("\nAvailable options:\n");
934 print_flag_list("-Z", config::DB_OPTIONS);
937 fn describe_codegen_flags() {
938 println!("\nAvailable codegen options:\n");
939 print_flag_list("-C", config::CG_OPTIONS);
942 fn print_flag_list<T>(
944 flag_list: &[(&'static str, T, Option<&'static str>, &'static str)],
946 let max_len = flag_list
948 .map(|&(name, _, opt_type_desc, _)| {
949 let extra_len = match opt_type_desc {
953 name.chars().count() + extra_len
958 for &(name, _, opt_type_desc, desc) in flag_list {
959 let (width, extra) = match opt_type_desc {
960 Some(..) => (max_len - 4, "=val"),
961 None => (max_len, ""),
964 " {} {:>width$}{} -- {}",
966 name.replace("_", "-"),
974 /// Process command line options. Emits messages as appropriate. If compilation
975 /// should continue, returns a getopts::Matches object parsed from args,
976 /// otherwise returns `None`.
978 /// The compiler's handling of options is a little complicated as it ties into
979 /// our stability story. The current intention of each compiler option is to
980 /// have one of two modes:
982 /// 1. An option is stable and can be used everywhere.
983 /// 2. An option is unstable, and can only be used on nightly.
985 /// Like unstable library and language features, however, unstable options have
986 /// always required a form of "opt in" to indicate that you're using them. This
987 /// provides the easy ability to scan a code base to check to see if anything
988 /// unstable is being used. Currently, this "opt in" is the `-Z` "zed" flag.
990 /// All options behind `-Z` are considered unstable by default. Other top-level
991 /// options can also be considered unstable, and they were unlocked through the
992 /// `-Z unstable-options` flag. Note that `-Z` remains to be the root of
993 /// instability in both cases, though.
995 /// So with all that in mind, the comments below have some more detail about the
996 /// contortions done here to get things to work out correctly.
997 pub fn handle_options(args: &[String]) -> Option<getopts::Matches> {
998 // Throw away the first argument, the name of the binary
999 let args = &args[1..];
1001 if args.is_empty() {
1002 // user did not write `-v` nor `-Z unstable-options`, so do not
1003 // include that extra information.
1004 usage(false, false);
1008 // Parse with *all* options defined in the compiler, we don't worry about
1009 // option stability here we just want to parse as much as possible.
1010 let mut options = getopts::Options::new();
1011 for option in config::rustc_optgroups() {
1012 (option.apply)(&mut options);
1014 let matches = options
1016 .unwrap_or_else(|f| early_error(ErrorOutputType::default(), &f.to_string()));
1018 // For all options we just parsed, we check a few aspects:
1020 // * If the option is stable, we're all good
1021 // * If the option wasn't passed, we're all good
1022 // * If `-Z unstable-options` wasn't passed (and we're not a -Z option
1023 // ourselves), then we require the `-Z unstable-options` flag to unlock
1024 // this option that was passed.
1025 // * If we're a nightly compiler, then unstable options are now unlocked, so
1026 // we're good to go.
1027 // * Otherwise, if we're an unstable option then we generate an error
1028 // (unstable option being used on stable)
1029 nightly_options::check_nightly_options(&matches, &config::rustc_optgroups());
1031 if matches.opt_present("h") || matches.opt_present("help") {
1032 // Only show unstable options in --help if we accept unstable options.
1033 usage(matches.opt_present("verbose"), nightly_options::is_unstable_enabled(&matches));
1037 // Handle the special case of -Wall.
1038 let wall = matches.opt_strs("W");
1039 if wall.iter().any(|x| *x == "all") {
1044 // Don't handle -W help here, because we might first load plugins.
1045 let r = matches.opt_strs("Z");
1046 if r.iter().any(|x| *x == "help") {
1047 describe_debug_flags();
1051 let cg_flags = matches.opt_strs("C");
1053 if cg_flags.iter().any(|x| *x == "help") {
1054 describe_codegen_flags();
1058 if cg_flags.iter().any(|x| *x == "no-stack-check") {
1060 ErrorOutputType::default(),
1061 "the --no-stack-check flag is deprecated and does nothing",
1065 if cg_flags.iter().any(|x| *x == "passes=list") {
1066 get_builtin_codegen_backend("llvm")().print_passes();
1070 if matches.opt_present("version") {
1071 version("rustc", &matches);
1078 fn parse_crate_attrs<'a>(sess: &'a Session, input: &Input) -> PResult<'a, Vec<ast::Attribute>> {
1080 Input::File(ifile) => rustc_parse::parse_crate_attrs_from_file(ifile, &sess.parse_sess),
1081 Input::Str { name, input } => rustc_parse::parse_crate_attrs_from_source_str(
1089 /// Gets a list of extra command-line flags provided by the user, as strings.
1091 /// This function is used during ICEs to show more information useful for
1092 /// debugging, since some ICEs only happens with non-default compiler flags
1093 /// (and the users don't always report them).
1094 fn extra_compiler_flags() -> Option<(Vec<String>, bool)> {
1095 let args = env::args_os().map(|arg| arg.to_string_lossy().to_string()).collect::<Vec<_>>();
1097 // Avoid printing help because of empty args. This can suggest the compiler
1098 // itself is not the program root (consider RLS).
1103 let matches = if let Some(matches) = handle_options(&args) {
1109 let mut result = Vec::new();
1110 let mut excluded_cargo_defaults = false;
1111 for flag in ICE_REPORT_COMPILER_FLAGS {
1112 let prefix = if flag.len() == 1 { "-" } else { "--" };
1114 for content in &matches.opt_strs(flag) {
1115 // Split always returns the first element
1116 let name = if let Some(first) = content.split('=').next() { first } else { &content };
1119 if ICE_REPORT_COMPILER_FLAGS_STRIP_VALUE.contains(&name) { name } else { content };
1121 if !ICE_REPORT_COMPILER_FLAGS_EXCLUDE.contains(&name) {
1122 result.push(format!("{}{} {}", prefix, flag, content));
1124 excluded_cargo_defaults = true;
1129 if !result.is_empty() { Some((result, excluded_cargo_defaults)) } else { None }
1132 /// Runs a closure and catches unwinds triggered by fatal errors.
1134 /// The compiler currently unwinds with a special sentinel value to abort
1135 /// compilation on fatal errors. This function catches that sentinel and turns
1136 /// the panic into a `Result` instead.
1137 pub fn catch_fatal_errors<F: FnOnce() -> R, R>(f: F) -> Result<R, ErrorReported> {
1138 catch_unwind(panic::AssertUnwindSafe(f)).map_err(|value| {
1139 if value.is::<rustc_errors::FatalErrorMarker>() {
1142 panic::resume_unwind(value);
1148 static ref DEFAULT_HOOK: Box<dyn Fn(&panic::PanicInfo<'_>) + Sync + Send + 'static> = {
1149 let hook = panic::take_hook();
1150 panic::set_hook(Box::new(|info| report_ice(info, BUG_REPORT_URL)));
1155 /// Prints the ICE message, including backtrace and query stack.
1157 /// The message will point the user at `bug_report_url` to report the ICE.
1159 /// When `install_ice_hook` is called, this function will be called as the panic
1161 pub fn report_ice(info: &panic::PanicInfo<'_>, bug_report_url: &str) {
1162 // Invoke the default handler, which prints the actual panic message and optionally a backtrace
1163 (*DEFAULT_HOOK)(info);
1165 // Separate the output with an empty line
1168 let emitter = Box::new(rustc_errors::emitter::EmitterWriter::stderr(
1169 rustc_errors::ColorConfig::Auto,
1176 let handler = rustc_errors::Handler::with_emitter(true, None, emitter);
1178 // a .span_bug or .bug call has already printed what
1179 // it wants to print.
1180 if !info.payload().is::<rustc_errors::ExplicitBug>() {
1181 let d = rustc_errors::Diagnostic::new(rustc_errors::Level::Bug, "unexpected panic");
1182 handler.emit_diagnostic(&d);
1185 let mut xs: Vec<Cow<'static, str>> = vec![
1186 "the compiler unexpectedly panicked. this is a bug.".into(),
1187 format!("we would appreciate a bug report: {}", bug_report_url).into(),
1189 "rustc {} running on {}",
1190 option_env!("CFG_VERSION").unwrap_or("unknown_version"),
1191 config::host_triple()
1196 if let Some((flags, excluded_cargo_defaults)) = extra_compiler_flags() {
1197 xs.push(format!("compiler flags: {}", flags.join(" ")).into());
1199 if excluded_cargo_defaults {
1200 xs.push("some of the compiler flags provided by cargo are hidden".into());
1205 handler.note_without_error(¬e);
1208 // If backtraces are enabled, also print the query stack
1209 let backtrace = env::var_os("RUST_BACKTRACE").map(|x| &x != "0").unwrap_or(false);
1212 TyCtxt::try_print_query_stack(&handler);
1217 if env::var("RUSTC_BREAK_ON_ICE").is_ok() {
1221 // Trigger a debugger if we crashed during bootstrap
1227 /// Installs a panic hook that will print the ICE message on unexpected panics.
1229 /// A custom rustc driver can skip calling this to set up a custom ICE hook.
1230 pub fn install_ice_hook() {
1231 lazy_static::initialize(&DEFAULT_HOOK);
1234 /// This allows tools to enable rust logging without having to magically match rustc's
1235 /// log crate version
1236 pub fn init_rustc_env_logger() {
1237 env_logger::init_from_env("RUSTC_LOG");
1241 let start = Instant::now();
1242 init_rustc_env_logger();
1243 let mut callbacks = TimePassesCallbacks::default();
1245 let result = catch_fatal_errors(|| {
1246 let args = env::args_os()
1249 arg.into_string().unwrap_or_else(|arg| {
1251 ErrorOutputType::default(),
1252 &format!("Argument {} is not valid Unicode: {:?}", i, arg),
1256 .collect::<Vec<_>>();
1257 run_compiler(&args, &mut callbacks, None, None)
1259 .and_then(|result| result);
1260 let exit_code = match result {
1261 Ok(_) => EXIT_SUCCESS,
1262 Err(_) => EXIT_FAILURE,
1264 // The extra `\t` is necessary to align this label with the others.
1265 print_time_passes_entry(callbacks.time_passes, "\ttotal", start.elapsed());
1266 process::exit(exit_code);