5 //! This API is completely unstable and subject to change.
7 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/")]
9 #![feature(box_syntax)]
10 #![cfg_attr(unix, feature(libc))]
12 #![feature(set_stdio)]
14 #![feature(integer_atomics)]
16 #![recursion_limit="256"]
18 pub extern crate getopts;
24 extern crate lazy_static;
26 pub extern crate rustc_plugin_impl as plugin;
28 //use rustc_resolve as resolve;
29 use rustc_save_analysis as save;
30 use rustc_save_analysis::DumpHandler;
31 use rustc::session::{config, Session, DiagnosticOutput};
32 use rustc::session::config::{Input, PrintRequest, ErrorOutputType, OutputType};
33 use rustc::session::config::nightly_options;
34 use rustc::session::{early_error, early_warn};
35 use rustc::lint::Lint;
37 use rustc::middle::cstore::MetadataLoader;
38 use rustc::hir::def_id::LOCAL_CRATE;
39 use rustc::ty::TyCtxt;
40 use rustc::util::common::{set_time_depth, time, print_time_passes_entry, ErrorReported};
41 use rustc_metadata::locator;
42 use rustc_codegen_utils::codegen_backend::CodegenBackend;
43 use errors::{PResult, registry::Registry};
44 use rustc_interface::interface;
45 use rustc_interface::util::get_codegen_sysroot;
46 use rustc_data_structures::sync::SeqCst;
47 use rustc_feature::find_gated_cfg;
49 use rustc_serialize::json::ToJson;
53 use std::default::Default;
55 use std::ffi::OsString;
56 use std::io::{self, Read, Write};
58 use std::panic::{self, catch_unwind};
59 use std::path::PathBuf;
60 use std::process::{self, Command, Stdio};
62 use std::time::Instant;
65 use syntax::source_map::FileLoader;
66 use syntax::feature_gate::UnstableFeatures;
67 use syntax_pos::symbol::sym;
68 use syntax_pos::FileName;
73 /// Exit status code used for successful compilation and help output.
74 pub const EXIT_SUCCESS: i32 = 0;
76 /// Exit status code used for compilation failures and invalid flags.
77 pub const EXIT_FAILURE: i32 = 1;
79 const BUG_REPORT_URL: &str = "https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.\
82 const ICE_REPORT_COMPILER_FLAGS: &[&str] = &["Z", "C", "crate-type"];
84 const ICE_REPORT_COMPILER_FLAGS_EXCLUDE: &[&str] = &["metadata", "extra-filename"];
86 const ICE_REPORT_COMPILER_FLAGS_STRIP_VALUE: &[&str] = &["incremental"];
88 pub fn abort_on_err<T>(result: Result<T, ErrorReported>, sess: &Session) -> T {
91 sess.abort_if_errors();
92 panic!("error reported but abort_if_errors didn't abort???");
99 /// Called before creating the compiler instance
100 fn config(&mut self, _config: &mut interface::Config) {}
101 /// Called after parsing. Return value instructs the compiler whether to
102 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
103 fn after_parsing(&mut self, _compiler: &interface::Compiler) -> Compilation {
104 Compilation::Continue
106 /// Called after expansion. Return value instructs the compiler whether to
107 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
108 fn after_expansion(&mut self, _compiler: &interface::Compiler) -> Compilation {
109 Compilation::Continue
111 /// Called after analysis. Return value instructs the compiler whether to
112 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
113 fn after_analysis(&mut self, _compiler: &interface::Compiler) -> Compilation {
114 Compilation::Continue
118 pub struct DefaultCallbacks;
120 impl Callbacks for DefaultCallbacks {}
123 pub struct TimePassesCallbacks {
127 impl Callbacks for TimePassesCallbacks {
128 fn config(&mut self, config: &mut interface::Config) {
129 // If a --prints=... option has been given, we don't print the "total"
130 // time because it will mess up the --prints output. See #64339.
132 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(ErrorOutputType::default(),
155 &format!("Failed to load argument file: {}", err)),
158 let diagnostic_output = emitter.map(|emitter| DiagnosticOutput::Raw(emitter))
159 .unwrap_or(DiagnosticOutput::Default);
160 let matches = match handle_options(&args) {
161 Some(matches) => matches,
162 None => return Ok(()),
165 let sopts = config::build_session_options(&matches);
166 let cfg = interface::parse_cfgspecs(matches.opt_strs("cfg"));
168 let mut dummy_config = |sopts, cfg, diagnostic_output| {
169 let mut config = interface::Config {
172 input: Input::File(PathBuf::new()),
180 lint_caps: Default::default(),
181 register_lints: None,
182 override_queries: None,
183 registry: diagnostics_registry(),
185 callbacks.config(&mut config);
189 if let Some(ref code) = matches.opt_str("explain") {
190 handle_explain(diagnostics_registry(), code, sopts.error_format);
194 let (odir, ofile) = make_output(&matches);
195 let (input, input_file_path, input_err) = match make_input(&matches.free) {
198 match matches.free.len() {
200 let config = dummy_config(sopts, cfg, diagnostic_output);
201 interface::run_compiler(config, |compiler| {
202 let sopts = &compiler.session().opts;
203 if sopts.describe_lints {
204 let lint_store = rustc_lint::new_lint_store(
205 sopts.debugging_opts.no_interleave_lints,
206 compiler.session().unstable_options(),
215 let should_stop = RustcDefaultCalls::print_crate_info(
216 &***compiler.codegen_backend(),
223 if should_stop == Compilation::Stop {
226 early_error(sopts.error_format, "no input filename given")
230 1 => panic!("make_input should have provided valid inputs"),
231 _ => early_error(sopts.error_format, &format!(
232 "multiple input filenames provided (first two filenames are `{}` and `{}`)",
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(),
276 ).and_then(|| RustcDefaultCalls::list_metadata(
278 &*compiler.codegen_backend().metadata_loader(),
283 if should_stop == Compilation::Stop {
284 return sess.compile_status();
289 if let Some(ppm) = &sess.opts.pretty {
290 if ppm.needs_ast_map() {
291 compiler.global_ctxt()?.peek_mut().enter(|tcx| {
292 let expanded_crate = compiler.expansion()?.take().0;
293 pretty::print_after_hir_lowering(
298 compiler.output_file().as_ref().map(|p| &**p),
303 let krate = compiler.parse()?.take();
304 pretty::print_after_parsing(
309 compiler.output_file().as_ref().map(|p| &**p),
312 return sess.compile_status();
315 if callbacks.after_parsing(compiler) == Compilation::Stop {
316 return sess.compile_status();
319 if sess.opts.debugging_opts.parse_only ||
320 sess.opts.debugging_opts.show_span.is_some() ||
321 sess.opts.debugging_opts.ast_json_noexpand {
322 return sess.compile_status();
326 let (_, lint_store) = &*compiler.register_plugins()?.peek();
328 // Lint plugins are registered; now we can process command line flags.
329 if sess.opts.describe_lints {
330 describe_lints(&sess, &lint_store, true);
331 return sess.compile_status();
335 compiler.expansion()?;
336 if callbacks.after_expansion(compiler) == Compilation::Stop {
337 return sess.compile_status();
340 compiler.prepare_outputs()?;
342 if sess.opts.output_types.contains_key(&OutputType::DepInfo)
343 && sess.opts.output_types.len() == 1
345 return sess.compile_status();
348 compiler.global_ctxt()?;
350 if sess.opts.debugging_opts.no_analysis ||
351 sess.opts.debugging_opts.ast_json {
352 return sess.compile_status();
355 if sess.opts.debugging_opts.save_analysis {
356 let expanded_crate = &compiler.expansion()?.peek().0;
357 let crate_name = compiler.crate_name()?.peek().clone();
358 compiler.global_ctxt()?.peek_mut().enter(|tcx| {
359 let result = tcx.analysis(LOCAL_CRATE);
361 time(sess, "save analysis", || {
368 DumpHandler::new(compiler.output_dir().as_ref().map(|p| &**p), &crate_name)
373 // AST will be dropped *after* the `after_analysis` callback
374 // (needed by the RLS)
377 // Drop AST after creating GlobalCtxt to free memory
378 mem::drop(compiler.expansion()?.take());
381 compiler.global_ctxt()?.peek_mut().enter(|tcx| tcx.analysis(LOCAL_CRATE))?;
383 if callbacks.after_analysis(compiler) == Compilation::Stop {
384 return sess.compile_status();
387 if sess.opts.debugging_opts.save_analysis {
388 mem::drop(compiler.expansion()?.take());
391 compiler.ongoing_codegen()?;
393 // Drop GlobalCtxt after starting codegen to free memory
394 mem::drop(compiler.global_ctxt()?.take());
396 if sess.opts.debugging_opts.print_type_sizes {
397 sess.code_stats.print_type_sizes();
402 if sess.opts.debugging_opts.perf_stats {
403 sess.print_perf_stats();
406 if sess.print_fuel_crate.is_some() {
407 eprintln!("Fuel used by {}: {}",
408 sess.print_fuel_crate.as_ref().unwrap(),
409 sess.print_fuel.load(SeqCst));
417 pub fn set_sigpipe_handler() {
419 // Set the SIGPIPE signal handler, so that an EPIPE
420 // will cause rustc to terminate, as expected.
421 assert_ne!(libc::signal(libc::SIGPIPE, libc::SIG_DFL), libc::SIG_ERR);
426 pub fn set_sigpipe_handler() {}
428 // Extract output directory and file from matches.
429 fn make_output(matches: &getopts::Matches) -> (Option<PathBuf>, Option<PathBuf>) {
430 let odir = matches.opt_str("out-dir").map(|o| PathBuf::from(&o));
431 let ofile = matches.opt_str("o").map(|o| PathBuf::from(&o));
435 // Extract input (string or file and optional path) from matches.
436 fn make_input(free_matches: &[String]) -> Option<(Input, Option<PathBuf>, Option<io::Error>)> {
437 if free_matches.len() == 1 {
438 let ifile = &free_matches[0];
440 let mut src = String::new();
441 let err = if io::stdin().read_to_string(&mut src).is_err() {
442 Some(io::Error::new(io::ErrorKind::InvalidData,
443 "couldn't read from stdin, as it did not contain valid UTF-8"))
447 if let Ok(path) = env::var("UNSTABLE_RUSTDOC_TEST_PATH") {
448 let line = env::var("UNSTABLE_RUSTDOC_TEST_LINE").
449 expect("when UNSTABLE_RUSTDOC_TEST_PATH is set \
450 UNSTABLE_RUSTDOC_TEST_LINE also needs to be set");
451 let line = isize::from_str_radix(&line, 10).
452 expect("UNSTABLE_RUSTDOC_TEST_LINE needs to be an number");
453 let file_name = FileName::doc_test_source_code(PathBuf::from(path), line);
454 return Some((Input::Str { name: file_name, input: src }, None, err));
456 Some((Input::Str { name: FileName::anon_source_code(&src), input: src },
459 Some((Input::File(PathBuf::from(ifile)),
460 Some(PathBuf::from(ifile)), None))
467 // Whether to stop or continue compilation.
468 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
469 pub enum Compilation {
475 pub fn and_then<F: FnOnce() -> Compilation>(self, next: F) -> Compilation {
477 Compilation::Stop => Compilation::Stop,
478 Compilation::Continue => next(),
483 /// CompilerCalls instance for a regular rustc build.
484 #[derive(Copy, Clone)]
485 pub struct RustcDefaultCalls;
487 // FIXME remove these and use winapi 0.3 instead
488 // Duplicates: bootstrap/compile.rs, librustc_errors/emitter.rs
490 fn stdout_isatty() -> bool {
491 unsafe { libc::isatty(libc::STDOUT_FILENO) != 0 }
495 fn stdout_isatty() -> bool {
498 type HANDLE = *mut u8;
499 type LPDWORD = *mut u32;
500 const STD_OUTPUT_HANDLE: DWORD = -11i32 as DWORD;
502 fn GetStdHandle(which: DWORD) -> HANDLE;
503 fn GetConsoleMode(hConsoleHandle: HANDLE, lpMode: LPDWORD) -> BOOL;
506 let handle = GetStdHandle(STD_OUTPUT_HANDLE);
508 GetConsoleMode(handle, &mut out) != 0
512 fn handle_explain(registry: Registry, code: &str, output: ErrorOutputType) {
513 let normalised = if code.starts_with("E") {
516 format!("E{0:0>4}", code)
518 match registry.find_description(&normalised) {
519 Some(ref description) => {
520 let mut is_in_code_block = false;
521 let mut text = String::new();
523 // Slice off the leading newline and print.
524 for line in description.lines() {
525 let indent_level = line.find(|c: char| !c.is_whitespace())
526 .unwrap_or_else(|| line.len());
527 let dedented_line = &line[indent_level..];
528 if dedented_line.starts_with("```") {
529 is_in_code_block = !is_in_code_block;
530 text.push_str(&line[..(indent_level + 3)]);
531 } else if is_in_code_block && dedented_line.starts_with("# ") {
540 show_content_with_pager(&text);
546 early_error(output, &format!("no extended information for {}", code));
551 fn show_content_with_pager(content: &String) {
552 let pager_name = env::var_os("PAGER").unwrap_or_else(|| if cfg!(windows) {
553 OsString::from("more.com")
555 OsString::from("less")
558 let mut fallback_to_println = false;
560 match Command::new(pager_name).stdin(Stdio::piped()).spawn() {
562 if let Some(pipe) = pager.stdin.as_mut() {
563 if pipe.write_all(content.as_bytes()).is_err() {
564 fallback_to_println = true;
568 if pager.wait().is_err() {
569 fallback_to_println = true;
573 fallback_to_println = true;
577 // If pager fails for whatever reason, we should still print the content
578 // to standard output
579 if fallback_to_println {
580 print!("{}", content);
584 impl RustcDefaultCalls {
585 pub fn list_metadata(sess: &Session,
586 metadata_loader: &dyn MetadataLoader,
587 matches: &getopts::Matches,
590 let r = matches.opt_strs("Z");
591 if r.iter().any(|s| *s == "ls") {
593 &Input::File(ref ifile) => {
594 let path = &(*ifile);
595 let mut v = Vec::new();
596 locator::list_file_metadata(&sess.target.target,
601 println!("{}", String::from_utf8(v).unwrap());
603 &Input::Str { .. } => {
604 early_error(ErrorOutputType::default(), "cannot list metadata for stdin");
607 return Compilation::Stop;
610 Compilation::Continue
614 fn print_crate_info(codegen_backend: &dyn CodegenBackend,
616 input: Option<&Input>,
617 odir: &Option<PathBuf>,
618 ofile: &Option<PathBuf>)
620 use rustc::session::config::PrintRequest::*;
621 // PrintRequest::NativeStaticLibs is special - printed during linking
622 // (empty iterator returns true)
623 if sess.opts.prints.iter().all(|&p| p == PrintRequest::NativeStaticLibs) {
624 return Compilation::Continue;
627 let attrs = match input {
630 let result = parse_crate_attrs(sess, input);
632 Ok(attrs) => Some(attrs),
633 Err(mut parse_error) => {
635 return Compilation::Stop;
640 for req in &sess.opts.prints {
643 let mut targets = rustc_target::spec::get_targets().collect::<Vec<String>>();
645 println!("{}", targets.join("\n"));
647 Sysroot => println!("{}", sess.sysroot.display()),
648 TargetSpec => println!("{}", sess.target.target.to_json().pretty()),
649 FileNames | CrateName => {
650 let input = input.unwrap_or_else(||
651 early_error(ErrorOutputType::default(), "no input file provided"));
652 let attrs = attrs.as_ref().unwrap();
653 let t_outputs = rustc_interface::util::build_output_filenames(
660 let id = rustc_codegen_utils::link::find_crate_name(Some(sess), attrs, input);
661 if *req == PrintRequest::CrateName {
665 let crate_types = rustc_interface::util::collect_crate_types(sess, attrs);
666 for &style in &crate_types {
667 let fname = rustc_codegen_utils::link::filename_for_input(
673 println!("{}", fname.file_name().unwrap().to_string_lossy());
677 let allow_unstable_cfg = UnstableFeatures::from_environment()
680 let mut cfgs = sess.parse_sess.config.iter().filter_map(|&(name, ref value)| {
681 // Note that crt-static is a specially recognized cfg
682 // directive that's printed out here as part of
683 // rust-lang/rust#37406, but in general the
684 // `target_feature` cfg is gated under
685 // rust-lang/rust#29717. For now this is just
686 // specifically allowing the crt-static cfg and that's
687 // it, this is intended to get into Cargo and then go
688 // through to build scripts.
689 let value = value.as_ref().map(|s| s.as_str());
690 let value = value.as_ref().map(|s| s.as_ref());
691 if (name != sym::target_feature || value != Some("crt-static"))
692 && !allow_unstable_cfg
693 && find_gated_cfg(|cfg_sym| cfg_sym == name).is_some()
698 if let Some(value) = value {
699 Some(format!("{}=\"{}\"", name, value))
701 Some(name.to_string())
703 }).collect::<Vec<String>>();
710 RelocationModels | CodeModels | TlsModels | TargetCPUs | TargetFeatures => {
711 codegen_backend.print(*req, sess);
713 // Any output here interferes with Cargo's parsing of other printed output
714 PrintRequest::NativeStaticLibs => {}
717 return Compilation::Stop;
721 /// Returns a version string such as "0.12.0-dev".
722 fn release_str() -> Option<&'static str> {
723 option_env!("CFG_RELEASE")
726 /// Returns the full SHA1 hash of HEAD of the Git repo from which rustc was built.
727 fn commit_hash_str() -> Option<&'static str> {
728 option_env!("CFG_VER_HASH")
731 /// Returns the "commit date" of HEAD of the Git repo from which rustc was built as a static string.
732 fn commit_date_str() -> Option<&'static str> {
733 option_env!("CFG_VER_DATE")
736 /// Prints version information
737 pub fn version(binary: &str, matches: &getopts::Matches) {
738 let verbose = matches.opt_present("verbose");
740 println!("{} {}", binary, option_env!("CFG_VERSION").unwrap_or("unknown version"));
743 fn unw(x: Option<&str>) -> &str {
744 x.unwrap_or("unknown")
746 println!("binary: {}", binary);
747 println!("commit-hash: {}", unw(commit_hash_str()));
748 println!("commit-date: {}", unw(commit_date_str()));
749 println!("host: {}", config::host_triple());
750 println!("release: {}", unw(release_str()));
751 get_codegen_sysroot("llvm")().print_version();
755 fn usage(verbose: bool, include_unstable_options: bool) {
756 let groups = if verbose {
757 config::rustc_optgroups()
759 config::rustc_short_optgroups()
761 let mut options = getopts::Options::new();
762 for option in groups.iter().filter(|x| include_unstable_options || x.is_stable()) {
763 (option.apply)(&mut options);
765 let message = "Usage: rustc [OPTIONS] INPUT";
766 let nightly_help = if nightly_options::is_nightly_build() {
767 "\n -Z help Print unstable compiler options"
771 let verbose_help = if verbose {
774 "\n --help -v Print the full set of options rustc accepts"
776 let at_path = if verbose && nightly_options::is_nightly_build() {
777 " @path Read newline separated options from `path`\n"
781 println!("{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);
791 fn print_wall_help() {
793 The flag `-Wall` does not exist in `rustc`. Most useful lints are enabled by
794 default. Use `rustc -W help` to see all available lints. It's more common to put
795 warning settings in the crate root using `#![warn(LINT_NAME)]` instead of using
796 the command line flag directly.
800 fn describe_lints(sess: &Session, lint_store: &lint::LintStore, loaded_plugins: bool) {
802 Available lint options:
803 -W <foo> Warn about <foo>
807 -F <foo> Forbid <foo> \
808 (deny <foo> and all attempts to override)
812 fn sort_lints(sess: &Session, mut lints: Vec<&'static Lint>) -> Vec<&'static Lint> {
813 // The sort doesn't case-fold but it's doubtful we care.
814 lints.sort_by_cached_key(|x: &&Lint| (x.default_level(sess), x.name));
818 fn sort_lint_groups(lints: Vec<(&'static str, Vec<lint::LintId>, bool)>)
819 -> Vec<(&'static str, Vec<lint::LintId>)> {
820 let mut lints: Vec<_> = lints.into_iter().map(|(x, y, _)| (x, y)).collect();
821 lints.sort_by_key(|l| l.0);
825 let (plugin, builtin): (Vec<_>, _) = lint_store.get_lints()
828 .partition(|&lint| lint.is_plugin);
829 let plugin = sort_lints(sess, plugin);
830 let builtin = sort_lints(sess, builtin);
832 let (plugin_groups, builtin_groups): (Vec<_>, _) = lint_store.get_lint_groups()
835 .partition(|&(.., p)| p);
836 let plugin_groups = sort_lint_groups(plugin_groups);
837 let builtin_groups = sort_lint_groups(builtin_groups);
839 let max_name_len = plugin.iter()
841 .map(|&s| s.name.chars().count())
844 let padded = |x: &str| {
845 let mut s = " ".repeat(max_name_len - x.chars().count());
850 println!("Lint checks provided by rustc:\n");
851 println!(" {} {:7.7} {}", padded("name"), "default", "meaning");
852 println!(" {} {:7.7} {}", padded("----"), "-------", "-------");
854 let print_lints = |lints: Vec<&Lint>| {
856 let name = lint.name_lower().replace("_", "-");
857 println!(" {} {:7.7} {}",
859 lint.default_level.as_str(),
865 print_lints(builtin);
867 let max_name_len = max("warnings".len(),
869 .chain(&builtin_groups)
870 .map(|&(s, _)| s.chars().count())
874 let padded = |x: &str| {
875 let mut s = " ".repeat(max_name_len - x.chars().count());
880 println!("Lint groups provided by rustc:\n");
881 println!(" {} {}", padded("name"), "sub-lints");
882 println!(" {} {}", padded("----"), "---------");
883 println!(" {} {}", padded("warnings"), "all lints that are set to issue warnings");
885 let print_lint_groups = |lints: Vec<(&'static str, Vec<lint::LintId>)>| {
886 for (name, to) in lints {
887 let name = name.to_lowercase().replace("_", "-");
888 let desc = to.into_iter()
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) => {
901 println!("Compiler plugins can provide additional lints and lint groups. To see a \
902 listing of these, re-run `rustc -W help` with a crate filename.");
904 (false, ..) => panic!("didn't load lint plugins but got them anyway!"),
905 (true, 0, 0) => println!("This crate does not load any lint plugins or lint groups."),
908 println!("Lint checks provided by plugins loaded by this crate:\n");
912 println!("Lint groups provided by plugins loaded by this crate:\n");
913 print_lint_groups(plugin_groups);
919 fn describe_debug_flags() {
920 println!("\nAvailable options:\n");
921 print_flag_list("-Z", config::DB_OPTIONS);
924 fn describe_codegen_flags() {
925 println!("\nAvailable codegen options:\n");
926 print_flag_list("-C", config::CG_OPTIONS);
929 fn print_flag_list<T>(cmdline_opt: &str,
930 flag_list: &[(&'static str, T, Option<&'static str>, &'static str)]) {
931 let max_len = flag_list.iter()
932 .map(|&(name, _, opt_type_desc, _)| {
933 let extra_len = match opt_type_desc {
937 name.chars().count() + extra_len
942 for &(name, _, opt_type_desc, desc) in flag_list {
943 let (width, extra) = match opt_type_desc {
944 Some(..) => (max_len - 4, "=val"),
945 None => (max_len, ""),
947 println!(" {} {:>width$}{} -- {}",
949 name.replace("_", "-"),
956 /// Process command line options. Emits messages as appropriate. If compilation
957 /// should continue, returns a getopts::Matches object parsed from args,
958 /// otherwise returns `None`.
960 /// The compiler's handling of options is a little complicated as it ties into
961 /// our stability story. The current intention of each compiler option is to
962 /// have one of two modes:
964 /// 1. An option is stable and can be used everywhere.
965 /// 2. An option is unstable, and can only be used on nightly.
967 /// Like unstable library and language features, however, unstable options have
968 /// always required a form of "opt in" to indicate that you're using them. This
969 /// provides the easy ability to scan a code base to check to see if anything
970 /// unstable is being used. Currently, this "opt in" is the `-Z` "zed" flag.
972 /// All options behind `-Z` are considered unstable by default. Other top-level
973 /// options can also be considered unstable, and they were unlocked through the
974 /// `-Z unstable-options` flag. Note that `-Z` remains to be the root of
975 /// instability in both cases, though.
977 /// So with all that in mind, the comments below have some more detail about the
978 /// contortions done here to get things to work out correctly.
979 pub fn handle_options(args: &[String]) -> Option<getopts::Matches> {
980 // Throw away the first argument, the name of the binary
981 let args = &args[1..];
984 // user did not write `-v` nor `-Z unstable-options`, so do not
985 // include that extra information.
990 // Parse with *all* options defined in the compiler, we don't worry about
991 // option stability here we just want to parse as much as possible.
992 let mut options = getopts::Options::new();
993 for option in config::rustc_optgroups() {
994 (option.apply)(&mut options);
996 let matches = options.parse(args).unwrap_or_else(|f|
997 early_error(ErrorOutputType::default(), &f.to_string()));
999 // For all options we just parsed, we check a few aspects:
1001 // * If the option is stable, we're all good
1002 // * If the option wasn't passed, we're all good
1003 // * If `-Z unstable-options` wasn't passed (and we're not a -Z option
1004 // ourselves), then we require the `-Z unstable-options` flag to unlock
1005 // this option that was passed.
1006 // * If we're a nightly compiler, then unstable options are now unlocked, so
1007 // we're good to go.
1008 // * Otherwise, if we're an unstable option then we generate an error
1009 // (unstable option being used on stable)
1010 nightly_options::check_nightly_options(&matches, &config::rustc_optgroups());
1012 if matches.opt_present("h") || matches.opt_present("help") {
1013 // Only show unstable options in --help if we accept unstable options.
1014 usage(matches.opt_present("verbose"), nightly_options::is_unstable_enabled(&matches));
1018 // Handle the special case of -Wall.
1019 let wall = matches.opt_strs("W");
1020 if wall.iter().any(|x| *x == "all") {
1025 // Don't handle -W help here, because we might first load plugins.
1026 let r = matches.opt_strs("Z");
1027 if r.iter().any(|x| *x == "help") {
1028 describe_debug_flags();
1032 let cg_flags = matches.opt_strs("C");
1034 if cg_flags.iter().any(|x| *x == "help") {
1035 describe_codegen_flags();
1039 if cg_flags.iter().any(|x| *x == "no-stack-check") {
1040 early_warn(ErrorOutputType::default(),
1041 "the --no-stack-check flag is deprecated and does nothing");
1044 if cg_flags.iter().any(|x| *x == "passes=list") {
1045 get_codegen_sysroot("llvm")().print_passes();
1049 if matches.opt_present("version") {
1050 version("rustc", &matches);
1057 fn parse_crate_attrs<'a>(sess: &'a Session, input: &Input) -> PResult<'a, Vec<ast::Attribute>> {
1059 Input::File(ifile) => {
1060 rustc_parse::parse_crate_attrs_from_file(ifile, &sess.parse_sess)
1062 Input::Str { name, input } => {
1063 rustc_parse::parse_crate_attrs_from_source_str(
1072 /// Gets a list of extra command-line flags provided by the user, as strings.
1074 /// This function is used during ICEs to show more information useful for
1075 /// debugging, since some ICEs only happens with non-default compiler flags
1076 /// (and the users don't always report them).
1077 fn extra_compiler_flags() -> Option<(Vec<String>, bool)> {
1078 let args = env::args_os().map(|arg| arg.to_string_lossy().to_string()).collect::<Vec<_>>();
1080 // Avoid printing help because of empty args. This can suggest the compiler
1081 // itself is not the program root (consider RLS).
1086 let matches = if let Some(matches) = handle_options(&args) {
1092 let mut result = Vec::new();
1093 let mut excluded_cargo_defaults = false;
1094 for flag in ICE_REPORT_COMPILER_FLAGS {
1095 let prefix = if flag.len() == 1 { "-" } else { "--" };
1097 for content in &matches.opt_strs(flag) {
1098 // Split always returns the first element
1099 let name = if let Some(first) = content.split('=').next() {
1105 let content = if ICE_REPORT_COMPILER_FLAGS_STRIP_VALUE.contains(&name) {
1111 if !ICE_REPORT_COMPILER_FLAGS_EXCLUDE.contains(&name) {
1112 result.push(format!("{}{} {}", prefix, flag, content));
1114 excluded_cargo_defaults = true;
1119 if !result.is_empty() {
1120 Some((result, excluded_cargo_defaults))
1126 /// Runs a closure and catches unwinds triggered by fatal errors.
1128 /// The compiler currently unwinds with a special sentinel value to abort
1129 /// compilation on fatal errors. This function catches that sentinel and turns
1130 /// the panic into a `Result` instead.
1131 pub fn catch_fatal_errors<F: FnOnce() -> R, R>(f: F) -> Result<R, ErrorReported> {
1132 catch_unwind(panic::AssertUnwindSafe(f)).map_err(|value| {
1133 if value.is::<errors::FatalErrorMarker>() {
1136 panic::resume_unwind(value);
1142 static ref DEFAULT_HOOK: Box<dyn Fn(&panic::PanicInfo<'_>) + Sync + Send + 'static> = {
1143 let hook = panic::take_hook();
1144 panic::set_hook(Box::new(|info| report_ice(info, BUG_REPORT_URL)));
1149 /// Prints the ICE message, including backtrace and query stack.
1151 /// The message will point the user at `bug_report_url` to report the ICE.
1153 /// When `install_ice_hook` is called, this function will be called as the panic
1155 pub fn report_ice(info: &panic::PanicInfo<'_>, bug_report_url: &str) {
1156 // Invoke the default handler, which prints the actual panic message and optionally a backtrace
1157 (*DEFAULT_HOOK)(info);
1159 // Separate the output with an empty line
1162 let emitter = Box::new(errors::emitter::EmitterWriter::stderr(
1163 errors::ColorConfig::Auto,
1170 let handler = errors::Handler::with_emitter(true, None, emitter);
1172 // a .span_bug or .bug call has already printed what
1173 // it wants to print.
1174 if !info.payload().is::<errors::ExplicitBug>() {
1175 let d = errors::Diagnostic::new(errors::Level::Bug, "unexpected panic");
1176 handler.emit_diagnostic(&d);
1177 handler.abort_if_errors_and_should_abort();
1180 let mut xs: Vec<Cow<'static, str>> = vec![
1181 "the compiler unexpectedly panicked. this is a bug.".into(),
1182 format!("we would appreciate a bug report: {}", bug_report_url).into(),
1183 format!("rustc {} running on {}",
1184 option_env!("CFG_VERSION").unwrap_or("unknown_version"),
1185 config::host_triple()).into(),
1188 if let Some((flags, excluded_cargo_defaults)) = extra_compiler_flags() {
1189 xs.push(format!("compiler flags: {}", flags.join(" ")).into());
1191 if excluded_cargo_defaults {
1192 xs.push("some of the compiler flags provided by cargo are hidden".into());
1197 handler.note_without_error(¬e);
1200 // If backtraces are enabled, also print the query stack
1201 let backtrace = env::var_os("RUST_BACKTRACE").map(|x| &x != "0").unwrap_or(false);
1204 TyCtxt::try_print_query_stack(&handler);
1209 if env::var("RUSTC_BREAK_ON_ICE").is_ok() {
1213 // Trigger a debugger if we crashed during bootstrap
1219 /// Installs a panic hook that will print the ICE message on unexpected panics.
1221 /// A custom rustc driver can skip calling this to set up a custom ICE hook.
1222 pub fn install_ice_hook() {
1223 lazy_static::initialize(&DEFAULT_HOOK);
1226 /// This allows tools to enable rust logging without having to magically match rustc's
1227 /// log crate version
1228 pub fn init_rustc_env_logger() {
1229 env_logger::init_from_env("RUSTC_LOG");
1233 let start = Instant::now();
1234 init_rustc_env_logger();
1235 let mut callbacks = TimePassesCallbacks::default();
1237 let result = catch_fatal_errors(|| {
1238 let args = env::args_os().enumerate()
1239 .map(|(i, arg)| arg.into_string().unwrap_or_else(|arg| {
1240 early_error(ErrorOutputType::default(),
1241 &format!("Argument {} is not valid Unicode: {:?}", i, arg))
1243 .collect::<Vec<_>>();
1244 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.
1252 print_time_passes_entry(callbacks.time_passes, "\ttotal", start.elapsed());
1253 process::exit(exit_code);