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 pretty::{PpMode, UserIdentifiedItem};
30 //use rustc_resolve as resolve;
31 use rustc_save_analysis as save;
32 use rustc_save_analysis::DumpHandler;
33 use rustc::session::{config, Session, DiagnosticOutput};
34 use rustc::session::config::{Input, PrintRequest, ErrorOutputType, OutputType};
35 use rustc::session::config::nightly_options;
36 use rustc::session::{early_error, early_warn};
37 use rustc::lint::Lint;
39 use rustc::middle::cstore::MetadataLoader;
40 use rustc::hir::def_id::LOCAL_CRATE;
41 use rustc::ty::TyCtxt;
42 use rustc::util::common::{set_time_depth, time, print_time_passes_entry, ErrorReported};
43 use rustc_metadata::locator;
44 use rustc_codegen_utils::codegen_backend::CodegenBackend;
45 use rustc_interface::interface;
46 use rustc_interface::util::get_codegen_sysroot;
47 use rustc_data_structures::sync::SeqCst;
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::{GatedCfg, UnstableFeatures};
67 use syntax::parse::{self, PResult};
68 use syntax::symbol::sym;
69 use syntax_pos::{DUMMY_SP, FileName};
74 /// Exit status code used for successful compilation and help output.
75 pub const EXIT_SUCCESS: i32 = 0;
77 /// Exit status code used for compilation failures and invalid flags.
78 pub const EXIT_FAILURE: i32 = 1;
80 const BUG_REPORT_URL: &str = "https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.\
83 const ICE_REPORT_COMPILER_FLAGS: &[&str] = &["Z", "C", "crate-type"];
85 const ICE_REPORT_COMPILER_FLAGS_EXCLUDE: &[&str] = &["metadata", "extra-filename"];
87 const ICE_REPORT_COMPILER_FLAGS_STRIP_VALUE: &[&str] = &["incremental"];
89 pub fn source_name(input: &Input) -> FileName {
91 Input::File(ref ifile) => ifile.clone().into(),
92 Input::Str { ref name, .. } => name.clone(),
96 pub fn abort_on_err<T>(result: Result<T, ErrorReported>, sess: &Session) -> T {
99 sess.abort_if_errors();
100 panic!("error reported but abort_if_errors didn't abort???");
106 pub trait Callbacks {
107 /// Called before creating the compiler instance
108 fn config(&mut self, _config: &mut interface::Config) {}
109 /// Called early during compilation to allow other drivers to easily register lints.
110 fn extra_lints(&mut self, _ls: &mut lint::LintStore) {}
111 /// Called after parsing. Return value instructs the compiler whether to
112 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
113 fn after_parsing(&mut self, _compiler: &interface::Compiler) -> Compilation {
114 Compilation::Continue
116 /// Called after expansion. Return value instructs the compiler whether to
117 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
118 fn after_expansion(&mut self, _compiler: &interface::Compiler) -> Compilation {
119 Compilation::Continue
121 /// Called after analysis. Return value instructs the compiler whether to
122 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
123 fn after_analysis(&mut self, _compiler: &interface::Compiler) -> Compilation {
124 Compilation::Continue
128 pub struct DefaultCallbacks;
130 impl Callbacks for DefaultCallbacks {}
133 pub struct TimePassesCallbacks {
137 impl Callbacks for TimePassesCallbacks {
138 fn config(&mut self, config: &mut interface::Config) {
139 // If a --prints=... option has been given, we don't print the "total"
140 // time because it will mess up the --prints output. See #64339.
142 config.opts.prints.is_empty() &&
143 (config.opts.debugging_opts.time_passes || config.opts.debugging_opts.time);
147 // Parse args and run the compiler. This is the primary entry point for rustc.
148 // See comments on CompilerCalls below for details about the callbacks argument.
149 // The FileLoader provides a way to load files from sources other than the file system.
152 callbacks: &mut (dyn Callbacks + Send),
153 file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
154 emitter: Option<Box<dyn Write + Send>>
155 ) -> interface::Result<()> {
156 let mut args = Vec::new();
158 match args::arg_expand(arg.clone()) {
159 Ok(arg) => args.extend(arg),
160 Err(err) => early_error(ErrorOutputType::default(),
161 &format!("Failed to load argument file: {}", err)),
164 let diagnostic_output = emitter.map(|emitter| DiagnosticOutput::Raw(emitter))
165 .unwrap_or(DiagnosticOutput::Default);
166 let matches = match handle_options(&args) {
167 Some(matches) => matches,
168 None => return Ok(()),
171 let sopts = config::build_session_options(&matches);
172 let cfg = interface::parse_cfgspecs(matches.opt_strs("cfg"));
174 let mut dummy_config = |sopts, cfg, diagnostic_output| {
175 let mut config = interface::Config {
178 input: Input::File(PathBuf::new()),
186 lint_caps: Default::default(),
187 register_lints: None,
189 callbacks.config(&mut config);
193 if let Some(ref code) = matches.opt_str("explain") {
194 handle_explain(code, sopts.error_format);
198 let (odir, ofile) = make_output(&matches);
199 let (input, input_file_path, input_err) = match make_input(&matches.free) {
202 match matches.free.len() {
204 let config = dummy_config(sopts, cfg, diagnostic_output);
205 interface::run_compiler(config, |compiler| {
206 let sopts = &compiler.session().opts;
207 if sopts.describe_lints {
208 let lint_store = rustc_lint::new_lint_store(
209 sopts.debugging_opts.no_interleave_lints,
210 compiler.session().unstable_options(),
219 let should_stop = RustcDefaultCalls::print_crate_info(
220 &***compiler.codegen_backend(),
227 if should_stop == Compilation::Stop {
230 early_error(sopts.error_format, "no input filename given")
234 1 => panic!("make_input should have provided valid inputs"),
235 _ => early_error(sopts.error_format, &format!(
236 "multiple input filenames provided (first two filenames are `{}` and `{}`)",
244 if let Some(err) = input_err {
245 // Immediately stop compilation if there was an issue reading
246 // the input (for example if the input stream is not UTF-8).
247 interface::run_compiler(dummy_config(sopts, cfg, diagnostic_output), |compiler| {
248 compiler.session().err(&err.to_string());
250 return Err(ErrorReported);
253 let mut config = interface::Config {
257 input_path: input_file_path,
264 lint_caps: Default::default(),
265 register_lints: None,
268 callbacks.config(&mut config);
270 interface::run_compiler(config, |compiler| {
271 let sess = compiler.session();
272 let should_stop = RustcDefaultCalls::print_crate_info(
273 &***compiler.codegen_backend(),
275 Some(compiler.input()),
276 compiler.output_dir(),
277 compiler.output_file(),
278 ).and_then(|| RustcDefaultCalls::list_metadata(
280 &*compiler.codegen_backend().metadata_loader(),
285 if should_stop == Compilation::Stop {
286 return sess.compile_status();
289 let pretty_info = parse_pretty(sess, &matches);
293 if let Some((ppm, opt_uii)) = pretty_info {
294 if ppm.needs_ast_map(&opt_uii) {
295 pretty::visit_crate(sess, &mut compiler.parse()?.peek_mut(), ppm);
296 compiler.global_ctxt()?.peek_mut().enter(|tcx| {
297 let expanded_crate = compiler.expansion()?.take().0;
298 pretty::print_after_hir_lowering(
304 compiler.output_file().as_ref().map(|p| &**p),
309 let mut krate = compiler.parse()?.take();
310 pretty::visit_crate(sess, &mut krate, ppm);
311 pretty::print_after_parsing(
316 compiler.output_file().as_ref().map(|p| &**p),
319 return sess.compile_status();
322 if callbacks.after_parsing(compiler) == Compilation::Stop {
323 return sess.compile_status();
326 if sess.opts.debugging_opts.parse_only ||
327 sess.opts.debugging_opts.show_span.is_some() ||
328 sess.opts.debugging_opts.ast_json_noexpand {
329 return sess.compile_status();
333 let (_, _, lint_store) = &*compiler.register_plugins()?.peek();
335 // Lint plugins are registered; now we can process command line flags.
336 if sess.opts.describe_lints {
337 describe_lints(&sess, &lint_store, true);
338 return sess.compile_status();
342 compiler.expansion()?;
343 if callbacks.after_expansion(compiler) == Compilation::Stop {
344 return sess.compile_status();
347 compiler.prepare_outputs()?;
349 if sess.opts.output_types.contains_key(&OutputType::DepInfo)
350 && sess.opts.output_types.len() == 1
352 return sess.compile_status();
355 compiler.global_ctxt()?;
357 if sess.opts.debugging_opts.no_analysis ||
358 sess.opts.debugging_opts.ast_json {
359 return sess.compile_status();
362 if sess.opts.debugging_opts.save_analysis {
363 let expanded_crate = &compiler.expansion()?.peek().0;
364 let crate_name = compiler.crate_name()?.peek().clone();
365 compiler.global_ctxt()?.peek_mut().enter(|tcx| {
366 let result = tcx.analysis(LOCAL_CRATE);
368 time(sess, "save analysis", || {
375 DumpHandler::new(compiler.output_dir().as_ref().map(|p| &**p), &crate_name)
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 mem::drop(compiler.expansion()?.take());
388 compiler.global_ctxt()?.peek_mut().enter(|tcx| tcx.analysis(LOCAL_CRATE))?;
390 if callbacks.after_analysis(compiler) == Compilation::Stop {
391 return sess.compile_status();
394 if sess.opts.debugging_opts.save_analysis {
395 mem::drop(compiler.expansion()?.take());
398 compiler.ongoing_codegen()?;
400 // Drop GlobalCtxt after starting codegen to free memory
401 mem::drop(compiler.global_ctxt()?.take());
403 if sess.opts.debugging_opts.print_type_sizes {
404 sess.code_stats.borrow().print_type_sizes();
409 if sess.opts.debugging_opts.perf_stats {
410 sess.print_perf_stats();
413 if sess.print_fuel_crate.is_some() {
414 eprintln!("Fuel used by {}: {}",
415 sess.print_fuel_crate.as_ref().unwrap(),
416 sess.print_fuel.load(SeqCst));
424 pub fn set_sigpipe_handler() {
426 // Set the SIGPIPE signal handler, so that an EPIPE
427 // will cause rustc to terminate, as expected.
428 assert_ne!(libc::signal(libc::SIGPIPE, libc::SIG_DFL), libc::SIG_ERR);
433 pub fn set_sigpipe_handler() {}
435 // Extract output directory and file from matches.
436 fn make_output(matches: &getopts::Matches) -> (Option<PathBuf>, Option<PathBuf>) {
437 let odir = matches.opt_str("out-dir").map(|o| PathBuf::from(&o));
438 let ofile = matches.opt_str("o").map(|o| PathBuf::from(&o));
442 // Extract input (string or file and optional path) from matches.
443 fn make_input(free_matches: &[String]) -> Option<(Input, Option<PathBuf>, Option<io::Error>)> {
444 if free_matches.len() == 1 {
445 let ifile = &free_matches[0];
447 let mut src = String::new();
448 let err = if io::stdin().read_to_string(&mut src).is_err() {
449 Some(io::Error::new(io::ErrorKind::InvalidData,
450 "couldn't read from stdin, as it did not contain valid UTF-8"))
454 if let Ok(path) = env::var("UNSTABLE_RUSTDOC_TEST_PATH") {
455 let line = env::var("UNSTABLE_RUSTDOC_TEST_LINE").
456 expect("when UNSTABLE_RUSTDOC_TEST_PATH is set \
457 UNSTABLE_RUSTDOC_TEST_LINE also needs to be set");
458 let line = isize::from_str_radix(&line, 10).
459 expect("UNSTABLE_RUSTDOC_TEST_LINE needs to be an number");
460 let file_name = FileName::doc_test_source_code(PathBuf::from(path), line);
461 return Some((Input::Str { name: file_name, input: src }, None, err));
463 Some((Input::Str { name: FileName::anon_source_code(&src), input: src },
466 Some((Input::File(PathBuf::from(ifile)),
467 Some(PathBuf::from(ifile)), None))
474 fn parse_pretty(sess: &Session,
475 matches: &getopts::Matches)
476 -> Option<(PpMode, Option<UserIdentifiedItem>)> {
477 let pretty = if sess.opts.debugging_opts.unstable_options {
478 matches.opt_default("pretty", "normal").map(|a| {
479 // stable pretty-print variants only
480 pretty::parse_pretty(sess, &a, false)
486 if pretty.is_none() {
487 sess.opts.debugging_opts.unpretty.as_ref().map(|a| {
488 // extended with unstable pretty-print variants
489 pretty::parse_pretty(sess, &a, true)
496 // Whether to stop or continue compilation.
497 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
498 pub enum Compilation {
504 pub fn and_then<F: FnOnce() -> Compilation>(self, next: F) -> Compilation {
506 Compilation::Stop => Compilation::Stop,
507 Compilation::Continue => next(),
512 /// CompilerCalls instance for a regular rustc build.
513 #[derive(Copy, Clone)]
514 pub struct RustcDefaultCalls;
516 // FIXME remove these and use winapi 0.3 instead
517 // Duplicates: bootstrap/compile.rs, librustc_errors/emitter.rs
519 fn stdout_isatty() -> bool {
520 unsafe { libc::isatty(libc::STDOUT_FILENO) != 0 }
524 fn stdout_isatty() -> bool {
527 type HANDLE = *mut u8;
528 type LPDWORD = *mut u32;
529 const STD_OUTPUT_HANDLE: DWORD = -11i32 as DWORD;
531 fn GetStdHandle(which: DWORD) -> HANDLE;
532 fn GetConsoleMode(hConsoleHandle: HANDLE, lpMode: LPDWORD) -> BOOL;
535 let handle = GetStdHandle(STD_OUTPUT_HANDLE);
537 GetConsoleMode(handle, &mut out) != 0
541 fn handle_explain(code: &str,
542 output: ErrorOutputType) {
543 let descriptions = rustc_interface::util::diagnostics_registry();
544 let normalised = if code.starts_with("E") {
547 format!("E{0:0>4}", code)
549 match descriptions.find_description(&normalised) {
550 Some(ref description) => {
551 let mut is_in_code_block = false;
552 let mut text = String::new();
554 // Slice off the leading newline and print.
555 for line in description[1..].lines() {
556 let indent_level = line.find(|c: char| !c.is_whitespace())
557 .unwrap_or_else(|| line.len());
558 let dedented_line = &line[indent_level..];
559 if dedented_line.starts_with("```") {
560 is_in_code_block = !is_in_code_block;
561 text.push_str(&line[..(indent_level+3)]);
562 } else if is_in_code_block && dedented_line.starts_with("# ") {
571 show_content_with_pager(&text);
577 early_error(output, &format!("no extended information for {}", code));
582 fn show_content_with_pager(content: &String) {
583 let pager_name = env::var_os("PAGER").unwrap_or_else(|| if cfg!(windows) {
584 OsString::from("more.com")
586 OsString::from("less")
589 let mut fallback_to_println = false;
591 match Command::new(pager_name).stdin(Stdio::piped()).spawn() {
593 if let Some(pipe) = pager.stdin.as_mut() {
594 if pipe.write_all(content.as_bytes()).is_err() {
595 fallback_to_println = true;
599 if pager.wait().is_err() {
600 fallback_to_println = true;
604 fallback_to_println = true;
608 // If pager fails for whatever reason, we should still print the content
609 // to standard output
610 if fallback_to_println {
611 print!("{}", content);
615 impl RustcDefaultCalls {
616 pub fn list_metadata(sess: &Session,
617 metadata_loader: &dyn MetadataLoader,
618 matches: &getopts::Matches,
621 let r = matches.opt_strs("Z");
622 if r.iter().any(|s| *s == "ls") {
624 &Input::File(ref ifile) => {
625 let path = &(*ifile);
626 let mut v = Vec::new();
627 locator::list_file_metadata(&sess.target.target,
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 fn print_crate_info(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"));
683 let attrs = attrs.as_ref().unwrap();
684 let t_outputs = rustc_interface::util::build_output_filenames(
691 let id = rustc_codegen_utils::link::find_crate_name(Some(sess), attrs, input);
692 if *req == PrintRequest::CrateName {
696 let crate_types = rustc_interface::util::collect_crate_types(sess, attrs);
697 for &style in &crate_types {
698 let fname = rustc_codegen_utils::link::filename_for_input(
704 println!("{}", fname.file_name().unwrap().to_string_lossy());
708 let allow_unstable_cfg = UnstableFeatures::from_environment()
711 let mut cfgs = sess.parse_sess.config.iter().filter_map(|&(name, ref value)| {
712 let gated_cfg = GatedCfg::gate(&ast::MetaItem {
713 path: ast::Path::from_ident(ast::Ident::with_dummy_span(name)),
714 kind: ast::MetaItemKind::Word,
718 // Note that crt-static is a specially recognized cfg
719 // directive that's printed out here as part of
720 // rust-lang/rust#37406, but in general the
721 // `target_feature` cfg is gated under
722 // rust-lang/rust#29717. For now this is just
723 // specifically allowing the crt-static cfg and that's
724 // it, this is intended to get into Cargo and then go
725 // through to build scripts.
726 let value = value.as_ref().map(|s| s.as_str());
727 let value = value.as_ref().map(|s| s.as_ref());
728 if name != sym::target_feature || value != Some("crt-static") {
729 if !allow_unstable_cfg && gated_cfg.is_some() {
734 if let Some(value) = value {
735 Some(format!("{}=\"{}\"", name, value))
737 Some(name.to_string())
739 }).collect::<Vec<String>>();
746 RelocationModels | CodeModels | TlsModels | TargetCPUs | TargetFeatures => {
747 codegen_backend.print(*req, sess);
749 // Any output here interferes with Cargo's parsing of other printed output
750 PrintRequest::NativeStaticLibs => {}
753 return Compilation::Stop;
757 /// Returns a version string such as "0.12.0-dev".
758 fn release_str() -> Option<&'static str> {
759 option_env!("CFG_RELEASE")
762 /// Returns the full SHA1 hash of HEAD of the Git repo from which rustc was built.
763 fn commit_hash_str() -> Option<&'static str> {
764 option_env!("CFG_VER_HASH")
767 /// Returns the "commit date" of HEAD of the Git repo from which rustc was built as a static string.
768 fn commit_date_str() -> Option<&'static str> {
769 option_env!("CFG_VER_DATE")
772 /// Prints version information
773 pub fn version(binary: &str, matches: &getopts::Matches) {
774 let verbose = matches.opt_present("verbose");
776 println!("{} {}", binary, option_env!("CFG_VERSION").unwrap_or("unknown version"));
779 fn unw(x: Option<&str>) -> &str {
780 x.unwrap_or("unknown")
782 println!("binary: {}", binary);
783 println!("commit-hash: {}", unw(commit_hash_str()));
784 println!("commit-date: {}", unw(commit_date_str()));
785 println!("host: {}", config::host_triple());
786 println!("release: {}", unw(release_str()));
787 get_codegen_sysroot("llvm")().print_version();
791 fn usage(verbose: bool, include_unstable_options: bool) {
792 let groups = if verbose {
793 config::rustc_optgroups()
795 config::rustc_short_optgroups()
797 let mut options = getopts::Options::new();
798 for option in groups.iter().filter(|x| include_unstable_options || x.is_stable()) {
799 (option.apply)(&mut options);
801 let message = "Usage: rustc [OPTIONS] INPUT";
802 let nightly_help = if nightly_options::is_nightly_build() {
803 "\n -Z help Print unstable compiler options"
807 let verbose_help = if verbose {
810 "\n --help -v Print the full set of options rustc accepts"
812 let at_path = if verbose && nightly_options::is_nightly_build() {
813 " @path Read newline separated options from `path`\n"
817 println!("{options}{at_path}\nAdditional help:
818 -C help Print codegen options
820 Print 'lint' options and default settings{nightly}{verbose}\n",
821 options = options.usage(message),
823 nightly = nightly_help,
824 verbose = verbose_help);
827 fn print_wall_help() {
829 The flag `-Wall` does not exist in `rustc`. Most useful lints are enabled by
830 default. Use `rustc -W help` to see all available lints. It's more common to put
831 warning settings in the crate root using `#![warn(LINT_NAME)]` instead of using
832 the command line flag directly.
836 fn describe_lints(sess: &Session, lint_store: &lint::LintStore, loaded_plugins: bool) {
838 Available lint options:
839 -W <foo> Warn about <foo>
843 -F <foo> Forbid <foo> \
844 (deny <foo> and all attempts to override)
848 fn sort_lints(sess: &Session, mut lints: Vec<&'static Lint>) -> Vec<&'static Lint> {
849 // The sort doesn't case-fold but it's doubtful we care.
850 lints.sort_by_cached_key(|x: &&Lint| (x.default_level(sess), x.name));
854 fn sort_lint_groups(lints: Vec<(&'static str, Vec<lint::LintId>, bool)>)
855 -> Vec<(&'static str, Vec<lint::LintId>)> {
856 let mut lints: Vec<_> = lints.into_iter().map(|(x, y, _)| (x, y)).collect();
857 lints.sort_by_key(|l| l.0);
861 let (plugin, builtin): (Vec<_>, _) = lint_store.get_lints()
864 .partition(|&lint| lint.is_plugin);
865 let plugin = sort_lints(sess, plugin);
866 let builtin = sort_lints(sess, builtin);
868 let (plugin_groups, builtin_groups): (Vec<_>, _) = lint_store.get_lint_groups()
871 .partition(|&(.., p)| p);
872 let plugin_groups = sort_lint_groups(plugin_groups);
873 let builtin_groups = sort_lint_groups(builtin_groups);
875 let max_name_len = plugin.iter()
877 .map(|&s| s.name.chars().count())
880 let padded = |x: &str| {
881 let mut s = " ".repeat(max_name_len - x.chars().count());
886 println!("Lint checks provided by rustc:\n");
887 println!(" {} {:7.7} {}", padded("name"), "default", "meaning");
888 println!(" {} {:7.7} {}", padded("----"), "-------", "-------");
890 let print_lints = |lints: Vec<&Lint>| {
892 let name = lint.name_lower().replace("_", "-");
893 println!(" {} {:7.7} {}",
895 lint.default_level.as_str(),
901 print_lints(builtin);
903 let max_name_len = max("warnings".len(),
905 .chain(&builtin_groups)
906 .map(|&(s, _)| s.chars().count())
910 let padded = |x: &str| {
911 let mut s = " ".repeat(max_name_len - x.chars().count());
916 println!("Lint groups provided by rustc:\n");
917 println!(" {} {}", padded("name"), "sub-lints");
918 println!(" {} {}", padded("----"), "---------");
919 println!(" {} {}", padded("warnings"), "all lints that are set to issue warnings");
921 let print_lint_groups = |lints: Vec<(&'static str, Vec<lint::LintId>)>| {
922 for (name, to) in lints {
923 let name = name.to_lowercase().replace("_", "-");
924 let desc = to.into_iter()
925 .map(|x| x.to_string().replace("_", "-"))
926 .collect::<Vec<String>>()
928 println!(" {} {}", padded(&name), desc);
933 print_lint_groups(builtin_groups);
935 match (loaded_plugins, plugin.len(), plugin_groups.len()) {
936 (false, 0, _) | (false, _, 0) => {
937 println!("Compiler plugins can provide additional lints and lint groups. To see a \
938 listing of these, re-run `rustc -W help` with a crate filename.");
940 (false, ..) => panic!("didn't load lint plugins but got them anyway!"),
941 (true, 0, 0) => println!("This crate does not load any lint plugins or lint groups."),
944 println!("Lint checks provided by plugins loaded by this crate:\n");
948 println!("Lint groups provided by plugins loaded by this crate:\n");
949 print_lint_groups(plugin_groups);
955 fn describe_debug_flags() {
956 println!("\nAvailable options:\n");
957 print_flag_list("-Z", config::DB_OPTIONS);
960 fn describe_codegen_flags() {
961 println!("\nAvailable codegen options:\n");
962 print_flag_list("-C", config::CG_OPTIONS);
965 fn print_flag_list<T>(cmdline_opt: &str,
966 flag_list: &[(&'static str, T, Option<&'static str>, &'static str)]) {
967 let max_len = flag_list.iter()
968 .map(|&(name, _, opt_type_desc, _)| {
969 let extra_len = match opt_type_desc {
973 name.chars().count() + extra_len
978 for &(name, _, opt_type_desc, desc) in flag_list {
979 let (width, extra) = match opt_type_desc {
980 Some(..) => (max_len - 4, "=val"),
981 None => (max_len, ""),
983 println!(" {} {:>width$}{} -- {}",
985 name.replace("_", "-"),
992 /// Process command line options. Emits messages as appropriate. If compilation
993 /// should continue, returns a getopts::Matches object parsed from args,
994 /// otherwise returns `None`.
996 /// The compiler's handling of options is a little complicated as it ties into
997 /// our stability story. The current intention of each compiler option is to
998 /// have one of two modes:
1000 /// 1. An option is stable and can be used everywhere.
1001 /// 2. An option is unstable, and can only be used on nightly.
1003 /// Like unstable library and language features, however, unstable options have
1004 /// always required a form of "opt in" to indicate that you're using them. This
1005 /// provides the easy ability to scan a code base to check to see if anything
1006 /// unstable is being used. Currently, this "opt in" is the `-Z` "zed" flag.
1008 /// All options behind `-Z` are considered unstable by default. Other top-level
1009 /// options can also be considered unstable, and they were unlocked through the
1010 /// `-Z unstable-options` flag. Note that `-Z` remains to be the root of
1011 /// instability in both cases, though.
1013 /// So with all that in mind, the comments below have some more detail about the
1014 /// contortions done here to get things to work out correctly.
1015 pub fn handle_options(args: &[String]) -> Option<getopts::Matches> {
1016 // Throw away the first argument, the name of the binary
1017 let args = &args[1..];
1019 if args.is_empty() {
1020 // user did not write `-v` nor `-Z unstable-options`, so do not
1021 // include that extra information.
1022 usage(false, false);
1026 // Parse with *all* options defined in the compiler, we don't worry about
1027 // option stability here we just want to parse as much as possible.
1028 let mut options = getopts::Options::new();
1029 for option in config::rustc_optgroups() {
1030 (option.apply)(&mut options);
1032 let matches = options.parse(args).unwrap_or_else(|f|
1033 early_error(ErrorOutputType::default(), &f.to_string()));
1035 // For all options we just parsed, we check a few aspects:
1037 // * If the option is stable, we're all good
1038 // * If the option wasn't passed, we're all good
1039 // * If `-Z unstable-options` wasn't passed (and we're not a -Z option
1040 // ourselves), then we require the `-Z unstable-options` flag to unlock
1041 // this option that was passed.
1042 // * If we're a nightly compiler, then unstable options are now unlocked, so
1043 // we're good to go.
1044 // * Otherwise, if we're an unstable option then we generate an error
1045 // (unstable option being used on stable)
1046 nightly_options::check_nightly_options(&matches, &config::rustc_optgroups());
1048 // Late check to see if @file was used without unstable options enabled
1049 if crate::args::used_unstable_argsfile() && !nightly_options::is_unstable_enabled(&matches) {
1050 early_error(ErrorOutputType::default(),
1051 "@path is unstable - use -Z unstable-options to enable its use");
1054 if matches.opt_present("h") || matches.opt_present("help") {
1055 // Only show unstable options in --help if we accept unstable options.
1056 usage(matches.opt_present("verbose"), nightly_options::is_unstable_enabled(&matches));
1060 // Handle the special case of -Wall.
1061 let wall = matches.opt_strs("W");
1062 if wall.iter().any(|x| *x == "all") {
1067 // Don't handle -W help here, because we might first load plugins.
1068 let r = matches.opt_strs("Z");
1069 if r.iter().any(|x| *x == "help") {
1070 describe_debug_flags();
1074 let cg_flags = matches.opt_strs("C");
1076 if cg_flags.iter().any(|x| *x == "help") {
1077 describe_codegen_flags();
1081 if cg_flags.iter().any(|x| *x == "no-stack-check") {
1082 early_warn(ErrorOutputType::default(),
1083 "the --no-stack-check flag is deprecated and does nothing");
1086 if cg_flags.iter().any(|x| *x == "passes=list") {
1087 get_codegen_sysroot("llvm")().print_passes();
1091 if matches.opt_present("version") {
1092 version("rustc", &matches);
1099 fn parse_crate_attrs<'a>(sess: &'a Session, input: &Input) -> PResult<'a, Vec<ast::Attribute>> {
1101 Input::File(ref ifile) => {
1102 parse::parse_crate_attrs_from_file(ifile, &sess.parse_sess)
1104 Input::Str { ref name, ref input } => {
1105 parse::parse_crate_attrs_from_source_str(name.clone(),
1112 /// Gets a list of extra command-line flags provided by the user, as strings.
1114 /// This function is used during ICEs to show more information useful for
1115 /// debugging, since some ICEs only happens with non-default compiler flags
1116 /// (and the users don't always report them).
1117 fn extra_compiler_flags() -> Option<(Vec<String>, bool)> {
1118 let args = env::args_os().map(|arg| arg.to_string_lossy().to_string()).collect::<Vec<_>>();
1120 // Avoid printing help because of empty args. This can suggest the compiler
1121 // itself is not the program root (consider RLS).
1126 let matches = if let Some(matches) = handle_options(&args) {
1132 let mut result = Vec::new();
1133 let mut excluded_cargo_defaults = false;
1134 for flag in ICE_REPORT_COMPILER_FLAGS {
1135 let prefix = if flag.len() == 1 { "-" } else { "--" };
1137 for content in &matches.opt_strs(flag) {
1138 // Split always returns the first element
1139 let name = if let Some(first) = content.split('=').next() {
1145 let content = if ICE_REPORT_COMPILER_FLAGS_STRIP_VALUE.contains(&name) {
1151 if !ICE_REPORT_COMPILER_FLAGS_EXCLUDE.contains(&name) {
1152 result.push(format!("{}{} {}", prefix, flag, content));
1154 excluded_cargo_defaults = true;
1159 if !result.is_empty() {
1160 Some((result, excluded_cargo_defaults))
1166 /// Runs a closure and catches unwinds triggered by fatal errors.
1168 /// The compiler currently unwinds with a special sentinel value to abort
1169 /// compilation on fatal errors. This function catches that sentinel and turns
1170 /// the panic into a `Result` instead.
1171 pub fn catch_fatal_errors<F: FnOnce() -> R, R>(f: F) -> Result<R, ErrorReported> {
1172 catch_unwind(panic::AssertUnwindSafe(f)).map_err(|value| {
1173 if value.is::<errors::FatalErrorMarker>() {
1176 panic::resume_unwind(value);
1182 static ref DEFAULT_HOOK: Box<dyn Fn(&panic::PanicInfo<'_>) + Sync + Send + 'static> = {
1183 let hook = panic::take_hook();
1184 panic::set_hook(Box::new(|info| report_ice(info, BUG_REPORT_URL)));
1189 /// Prints the ICE message, including backtrace and query stack.
1191 /// The message will point the user at `bug_report_url` to report the ICE.
1193 /// When `install_ice_hook` is called, this function will be called as the panic
1195 pub fn report_ice(info: &panic::PanicInfo<'_>, bug_report_url: &str) {
1196 // Invoke the default handler, which prints the actual panic message and optionally a backtrace
1197 (*DEFAULT_HOOK)(info);
1199 // Separate the output with an empty line
1202 let emitter = Box::new(errors::emitter::EmitterWriter::stderr(
1203 errors::ColorConfig::Auto,
1210 let handler = errors::Handler::with_emitter(true, None, emitter);
1212 // a .span_bug or .bug call has already printed what
1213 // it wants to print.
1214 if !info.payload().is::<errors::ExplicitBug>() {
1215 let d = errors::Diagnostic::new(errors::Level::Bug, "unexpected panic");
1216 handler.emit_diagnostic(&d);
1217 handler.abort_if_errors_and_should_abort();
1220 let mut xs: Vec<Cow<'static, str>> = vec![
1221 "the compiler unexpectedly panicked. this is a bug.".into(),
1222 format!("we would appreciate a bug report: {}", bug_report_url).into(),
1223 format!("rustc {} running on {}",
1224 option_env!("CFG_VERSION").unwrap_or("unknown_version"),
1225 config::host_triple()).into(),
1228 if let Some((flags, excluded_cargo_defaults)) = extra_compiler_flags() {
1229 xs.push(format!("compiler flags: {}", flags.join(" ")).into());
1231 if excluded_cargo_defaults {
1232 xs.push("some of the compiler flags provided by cargo are hidden".into());
1237 handler.note_without_error(¬e);
1240 // If backtraces are enabled, also print the query stack
1241 let backtrace = env::var_os("RUST_BACKTRACE").map(|x| &x != "0").unwrap_or(false);
1244 TyCtxt::try_print_query_stack(&handler);
1249 if env::var("RUSTC_BREAK_ON_ICE").is_ok() {
1253 // Trigger a debugger if we crashed during bootstrap
1259 /// Installs a panic hook that will print the ICE message on unexpected panics.
1261 /// A custom rustc driver can skip calling this to set up a custom ICE hook.
1262 pub fn install_ice_hook() {
1263 lazy_static::initialize(&DEFAULT_HOOK);
1266 /// This allows tools to enable rust logging without having to magically match rustc's
1267 /// log crate version
1268 pub fn init_rustc_env_logger() {
1269 env_logger::init_from_env("RUSTC_LOG");
1273 let start = Instant::now();
1274 init_rustc_env_logger();
1275 let mut callbacks = TimePassesCallbacks::default();
1277 let result = catch_fatal_errors(|| {
1278 let args = env::args_os().enumerate()
1279 .map(|(i, arg)| arg.into_string().unwrap_or_else(|arg| {
1280 early_error(ErrorOutputType::default(),
1281 &format!("Argument {} is not valid Unicode: {:?}", i, arg))
1283 .collect::<Vec<_>>();
1284 run_compiler(&args, &mut callbacks, None, None)
1285 }).and_then(|result| result);
1286 let exit_code = match result {
1287 Ok(_) => EXIT_SUCCESS,
1288 Err(_) => EXIT_FAILURE,
1290 // The extra `\t` is necessary to align this label with the others.
1292 print_time_passes_entry(callbacks.time_passes, "\ttotal", start.elapsed());
1293 process::exit(exit_code);