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::hir::def_id::LOCAL_CRATE;
40 use rustc::ty::TyCtxt;
41 use rustc::util::common::{set_time_depth, time, print_time_passes_entry, ErrorReported};
42 use rustc_metadata::locator;
43 use rustc_metadata::cstore::CStore;
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 after parsing. Return value instructs the compiler whether to
110 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
111 fn after_parsing(&mut self, _compiler: &interface::Compiler) -> Compilation {
112 Compilation::Continue
114 /// Called after expansion. Return value instructs the compiler whether to
115 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
116 fn after_expansion(&mut self, _compiler: &interface::Compiler) -> Compilation {
117 Compilation::Continue
119 /// Called after analysis. Return value instructs the compiler whether to
120 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
121 fn after_analysis(&mut self, _compiler: &interface::Compiler) -> Compilation {
122 Compilation::Continue
126 pub struct DefaultCallbacks;
128 impl Callbacks for DefaultCallbacks {}
131 pub struct TimePassesCallbacks {
135 impl Callbacks for TimePassesCallbacks {
136 fn config(&mut self, config: &mut interface::Config) {
137 // If a --prints=... option has been given, we don't print the "total"
138 // time because it will mess up the --prints output. See #64339.
140 config.opts.prints.is_empty() &&
141 (config.opts.debugging_opts.time_passes || config.opts.debugging_opts.time);
145 // Parse args and run the compiler. This is the primary entry point for rustc.
146 // See comments on CompilerCalls below for details about the callbacks argument.
147 // The FileLoader provides a way to load files from sources other than the file system.
150 callbacks: &mut (dyn Callbacks + Send),
151 file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
152 emitter: Option<Box<dyn Write + Send>>
153 ) -> interface::Result<()> {
154 let mut args = Vec::new();
156 match args::arg_expand(arg.clone()) {
157 Ok(arg) => args.extend(arg),
158 Err(err) => early_error(ErrorOutputType::default(),
159 &format!("Failed to load argument file: {}", err)),
162 let diagnostic_output = emitter.map(|emitter| DiagnosticOutput::Raw(emitter))
163 .unwrap_or(DiagnosticOutput::Default);
164 let matches = match handle_options(&args) {
165 Some(matches) => matches,
166 None => return Ok(()),
169 let sopts = config::build_session_options(&matches);
170 let cfg = interface::parse_cfgspecs(matches.opt_strs("cfg"));
172 let mut dummy_config = |sopts, cfg, diagnostic_output| {
173 let mut config = interface::Config {
176 input: Input::File(PathBuf::new()),
184 lint_caps: Default::default(),
186 callbacks.config(&mut config);
190 if let Some(ref code) = matches.opt_str("explain") {
191 handle_explain(code, sopts.error_format);
195 let (odir, ofile) = make_output(&matches);
196 let (input, input_file_path, input_err) = match make_input(&matches.free) {
199 match matches.free.len() {
201 let config = dummy_config(sopts, cfg, diagnostic_output);
202 interface::run_compiler(config, |compiler| {
203 let sopts = &compiler.session().opts;
204 if sopts.describe_lints {
207 &*compiler.session().lint_store.borrow(),
212 let should_stop = RustcDefaultCalls::print_crate_info(
213 &***compiler.codegen_backend(),
220 if should_stop == Compilation::Stop {
223 early_error(sopts.error_format, "no input filename given")
227 1 => panic!("make_input should have provided valid inputs"),
228 _ => early_error(sopts.error_format, &format!(
229 "multiple input filenames provided (first two filenames are `{}` and `{}`)",
237 if let Some(err) = input_err {
238 // Immediately stop compilation if there was an issue reading
239 // the input (for example if the input stream is not UTF-8).
240 interface::run_compiler(dummy_config(sopts, cfg, diagnostic_output), |compiler| {
241 compiler.session().err(&err.to_string());
243 return Err(ErrorReported);
246 let mut config = interface::Config {
250 input_path: input_file_path,
257 lint_caps: Default::default(),
260 callbacks.config(&mut config);
262 interface::run_compiler(config, |compiler| {
263 let sess = compiler.session();
264 let should_stop = RustcDefaultCalls::print_crate_info(
265 &***compiler.codegen_backend(),
267 Some(compiler.input()),
268 compiler.output_dir(),
269 compiler.output_file(),
270 ).and_then(|| RustcDefaultCalls::list_metadata(
277 if should_stop == Compilation::Stop {
278 return sess.compile_status();
281 let pretty_info = parse_pretty(sess, &matches);
285 if let Some((ppm, opt_uii)) = pretty_info {
286 if ppm.needs_ast_map(&opt_uii) {
287 pretty::visit_crate(sess, &mut compiler.parse()?.peek_mut(), ppm);
288 compiler.global_ctxt()?.peek_mut().enter(|tcx| {
289 let expanded_crate = compiler.expansion()?.take().0;
290 pretty::print_after_hir_lowering(
296 compiler.output_file().as_ref().map(|p| &**p),
301 let mut krate = compiler.parse()?.take();
302 pretty::visit_crate(sess, &mut krate, ppm);
303 pretty::print_after_parsing(
308 compiler.output_file().as_ref().map(|p| &**p),
311 return sess.compile_status();
314 if callbacks.after_parsing(compiler) == Compilation::Stop {
315 return sess.compile_status();
318 if sess.opts.debugging_opts.parse_only ||
319 sess.opts.debugging_opts.show_span.is_some() ||
320 sess.opts.debugging_opts.ast_json_noexpand {
321 return sess.compile_status();
324 compiler.register_plugins()?;
326 // Lint plugins are registered; now we can process command line flags.
327 if sess.opts.describe_lints {
328 describe_lints(&sess, &sess.lint_store.borrow(), true);
329 return sess.compile_status();
332 compiler.expansion()?;
333 if callbacks.after_expansion(compiler) == Compilation::Stop {
334 return sess.compile_status();
337 compiler.prepare_outputs()?;
339 if sess.opts.output_types.contains_key(&OutputType::DepInfo)
340 && sess.opts.output_types.len() == 1
342 return sess.compile_status();
345 compiler.global_ctxt()?;
347 if sess.opts.debugging_opts.no_analysis ||
348 sess.opts.debugging_opts.ast_json {
349 return sess.compile_status();
352 if sess.opts.debugging_opts.save_analysis {
353 let expanded_crate = &compiler.expansion()?.peek().0;
354 let crate_name = compiler.crate_name()?.peek().clone();
355 compiler.global_ctxt()?.peek_mut().enter(|tcx| {
356 let result = tcx.analysis(LOCAL_CRATE);
358 time(sess, "save analysis", || {
365 DumpHandler::new(compiler.output_dir().as_ref().map(|p| &**p), &crate_name)
370 // AST will be dropped *after* the `after_analysis` callback
371 // (needed by the RLS)
374 // Drop AST after creating GlobalCtxt to free memory
375 mem::drop(compiler.expansion()?.take());
378 compiler.global_ctxt()?.peek_mut().enter(|tcx| tcx.analysis(LOCAL_CRATE))?;
380 if callbacks.after_analysis(compiler) == Compilation::Stop {
381 return sess.compile_status();
384 if sess.opts.debugging_opts.save_analysis {
385 mem::drop(compiler.expansion()?.take());
388 compiler.ongoing_codegen()?;
390 // Drop GlobalCtxt after starting codegen to free memory
391 mem::drop(compiler.global_ctxt()?.take());
393 if sess.opts.debugging_opts.print_type_sizes {
394 sess.code_stats.borrow().print_type_sizes();
399 if sess.opts.debugging_opts.perf_stats {
400 sess.print_perf_stats();
403 if sess.print_fuel_crate.is_some() {
404 eprintln!("Fuel used by {}: {}",
405 sess.print_fuel_crate.as_ref().unwrap(),
406 sess.print_fuel.load(SeqCst));
414 pub fn set_sigpipe_handler() {
416 // Set the SIGPIPE signal handler, so that an EPIPE
417 // will cause rustc to terminate, as expected.
418 assert_ne!(libc::signal(libc::SIGPIPE, libc::SIG_DFL), libc::SIG_ERR);
423 pub fn set_sigpipe_handler() {}
425 // Extract output directory and file from matches.
426 fn make_output(matches: &getopts::Matches) -> (Option<PathBuf>, Option<PathBuf>) {
427 let odir = matches.opt_str("out-dir").map(|o| PathBuf::from(&o));
428 let ofile = matches.opt_str("o").map(|o| PathBuf::from(&o));
432 // Extract input (string or file and optional path) from matches.
433 fn make_input(free_matches: &[String]) -> Option<(Input, Option<PathBuf>, Option<io::Error>)> {
434 if free_matches.len() == 1 {
435 let ifile = &free_matches[0];
437 let mut src = String::new();
438 let err = if io::stdin().read_to_string(&mut src).is_err() {
439 Some(io::Error::new(io::ErrorKind::InvalidData,
440 "couldn't read from stdin, as it did not contain valid UTF-8"))
444 if let Ok(path) = env::var("UNSTABLE_RUSTDOC_TEST_PATH") {
445 let line = env::var("UNSTABLE_RUSTDOC_TEST_LINE").
446 expect("when UNSTABLE_RUSTDOC_TEST_PATH is set \
447 UNSTABLE_RUSTDOC_TEST_LINE also needs to be set");
448 let line = isize::from_str_radix(&line, 10).
449 expect("UNSTABLE_RUSTDOC_TEST_LINE needs to be an number");
450 let file_name = FileName::doc_test_source_code(PathBuf::from(path), line);
451 return Some((Input::Str { name: file_name, input: src }, None, err));
453 Some((Input::Str { name: FileName::anon_source_code(&src), input: src },
456 Some((Input::File(PathBuf::from(ifile)),
457 Some(PathBuf::from(ifile)), None))
464 fn parse_pretty(sess: &Session,
465 matches: &getopts::Matches)
466 -> Option<(PpMode, Option<UserIdentifiedItem>)> {
467 let pretty = if sess.opts.debugging_opts.unstable_options {
468 matches.opt_default("pretty", "normal").map(|a| {
469 // stable pretty-print variants only
470 pretty::parse_pretty(sess, &a, false)
476 if pretty.is_none() {
477 sess.opts.debugging_opts.unpretty.as_ref().map(|a| {
478 // extended with unstable pretty-print variants
479 pretty::parse_pretty(sess, &a, true)
486 // Whether to stop or continue compilation.
487 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
488 pub enum Compilation {
494 pub fn and_then<F: FnOnce() -> Compilation>(self, next: F) -> Compilation {
496 Compilation::Stop => Compilation::Stop,
497 Compilation::Continue => next(),
502 /// CompilerCalls instance for a regular rustc build.
503 #[derive(Copy, Clone)]
504 pub struct RustcDefaultCalls;
506 // FIXME remove these and use winapi 0.3 instead
507 // Duplicates: bootstrap/compile.rs, librustc_errors/emitter.rs
509 fn stdout_isatty() -> bool {
510 unsafe { libc::isatty(libc::STDOUT_FILENO) != 0 }
514 fn stdout_isatty() -> bool {
517 type HANDLE = *mut u8;
518 type LPDWORD = *mut u32;
519 const STD_OUTPUT_HANDLE: DWORD = -11i32 as DWORD;
521 fn GetStdHandle(which: DWORD) -> HANDLE;
522 fn GetConsoleMode(hConsoleHandle: HANDLE, lpMode: LPDWORD) -> BOOL;
525 let handle = GetStdHandle(STD_OUTPUT_HANDLE);
527 GetConsoleMode(handle, &mut out) != 0
531 fn handle_explain(code: &str,
532 output: ErrorOutputType) {
533 let descriptions = rustc_interface::util::diagnostics_registry();
534 let normalised = if code.starts_with("E") {
537 format!("E{0:0>4}", code)
539 match descriptions.find_description(&normalised) {
540 Some(ref description) => {
541 let mut is_in_code_block = false;
542 let mut text = String::new();
544 // Slice off the leading newline and print.
545 for line in description[1..].lines() {
546 let indent_level = line.find(|c: char| !c.is_whitespace())
547 .unwrap_or_else(|| line.len());
548 let dedented_line = &line[indent_level..];
549 if dedented_line.starts_with("```") {
550 is_in_code_block = !is_in_code_block;
551 text.push_str(&line[..(indent_level+3)]);
552 } else if is_in_code_block && dedented_line.starts_with("# ") {
561 show_content_with_pager(&text);
567 early_error(output, &format!("no extended information for {}", code));
572 fn show_content_with_pager(content: &String) {
573 let pager_name = env::var_os("PAGER").unwrap_or_else(|| if cfg!(windows) {
574 OsString::from("more.com")
576 OsString::from("less")
579 let mut fallback_to_println = false;
581 match Command::new(pager_name).stdin(Stdio::piped()).spawn() {
583 if let Some(pipe) = pager.stdin.as_mut() {
584 if pipe.write_all(content.as_bytes()).is_err() {
585 fallback_to_println = true;
589 if pager.wait().is_err() {
590 fallback_to_println = true;
594 fallback_to_println = true;
598 // If pager fails for whatever reason, we should still print the content
599 // to standard output
600 if fallback_to_println {
601 print!("{}", content);
605 impl RustcDefaultCalls {
606 pub fn list_metadata(sess: &Session,
608 matches: &getopts::Matches,
611 let r = matches.opt_strs("Z");
612 if r.iter().any(|s| *s == "ls") {
614 &Input::File(ref ifile) => {
615 let path = &(*ifile);
616 let mut v = Vec::new();
617 locator::list_file_metadata(&sess.target.target,
622 println!("{}", String::from_utf8(v).unwrap());
624 &Input::Str { .. } => {
625 early_error(ErrorOutputType::default(), "cannot list metadata for stdin");
628 return Compilation::Stop;
631 Compilation::Continue
635 fn print_crate_info(codegen_backend: &dyn CodegenBackend,
637 input: Option<&Input>,
638 odir: &Option<PathBuf>,
639 ofile: &Option<PathBuf>)
641 use rustc::session::config::PrintRequest::*;
642 // PrintRequest::NativeStaticLibs is special - printed during linking
643 // (empty iterator returns true)
644 if sess.opts.prints.iter().all(|&p| p == PrintRequest::NativeStaticLibs) {
645 return Compilation::Continue;
648 let attrs = match input {
651 let result = parse_crate_attrs(sess, input);
653 Ok(attrs) => Some(attrs),
654 Err(mut parse_error) => {
656 return Compilation::Stop;
661 for req in &sess.opts.prints {
664 let mut targets = rustc_target::spec::get_targets().collect::<Vec<String>>();
666 println!("{}", targets.join("\n"));
668 Sysroot => println!("{}", sess.sysroot.display()),
669 TargetSpec => println!("{}", sess.target.target.to_json().pretty()),
670 FileNames | CrateName => {
671 let input = input.unwrap_or_else(||
672 early_error(ErrorOutputType::default(), "no input file provided"));
673 let attrs = attrs.as_ref().unwrap();
674 let t_outputs = rustc_interface::util::build_output_filenames(
681 let id = rustc_codegen_utils::link::find_crate_name(Some(sess), attrs, input);
682 if *req == PrintRequest::CrateName {
686 let crate_types = rustc_interface::util::collect_crate_types(sess, attrs);
687 for &style in &crate_types {
688 let fname = rustc_codegen_utils::link::filename_for_input(
694 println!("{}", fname.file_name().unwrap().to_string_lossy());
698 let allow_unstable_cfg = UnstableFeatures::from_environment()
701 let mut cfgs = sess.parse_sess.config.iter().filter_map(|&(name, ref value)| {
702 let gated_cfg = GatedCfg::gate(&ast::MetaItem {
703 path: ast::Path::from_ident(ast::Ident::with_dummy_span(name)),
704 kind: ast::MetaItemKind::Word,
708 // Note that crt-static is a specially recognized cfg
709 // directive that's printed out here as part of
710 // rust-lang/rust#37406, but in general the
711 // `target_feature` cfg is gated under
712 // rust-lang/rust#29717. For now this is just
713 // specifically allowing the crt-static cfg and that's
714 // it, this is intended to get into Cargo and then go
715 // through to build scripts.
716 let value = value.as_ref().map(|s| s.as_str());
717 let value = value.as_ref().map(|s| s.as_ref());
718 if name != sym::target_feature || value != Some("crt-static") {
719 if !allow_unstable_cfg && gated_cfg.is_some() {
724 if let Some(value) = value {
725 Some(format!("{}=\"{}\"", name, value))
727 Some(name.to_string())
729 }).collect::<Vec<String>>();
736 RelocationModels | CodeModels | TlsModels | TargetCPUs | TargetFeatures => {
737 codegen_backend.print(*req, sess);
739 // Any output here interferes with Cargo's parsing of other printed output
740 PrintRequest::NativeStaticLibs => {}
743 return Compilation::Stop;
747 /// Returns a version string such as "0.12.0-dev".
748 fn release_str() -> Option<&'static str> {
749 option_env!("CFG_RELEASE")
752 /// Returns the full SHA1 hash of HEAD of the Git repo from which rustc was built.
753 fn commit_hash_str() -> Option<&'static str> {
754 option_env!("CFG_VER_HASH")
757 /// Returns the "commit date" of HEAD of the Git repo from which rustc was built as a static string.
758 fn commit_date_str() -> Option<&'static str> {
759 option_env!("CFG_VER_DATE")
762 /// Prints version information
763 pub fn version(binary: &str, matches: &getopts::Matches) {
764 let verbose = matches.opt_present("verbose");
766 println!("{} {}", binary, option_env!("CFG_VERSION").unwrap_or("unknown version"));
769 fn unw(x: Option<&str>) -> &str {
770 x.unwrap_or("unknown")
772 println!("binary: {}", binary);
773 println!("commit-hash: {}", unw(commit_hash_str()));
774 println!("commit-date: {}", unw(commit_date_str()));
775 println!("host: {}", config::host_triple());
776 println!("release: {}", unw(release_str()));
777 get_codegen_sysroot("llvm")().print_version();
781 fn usage(verbose: bool, include_unstable_options: bool) {
782 let groups = if verbose {
783 config::rustc_optgroups()
785 config::rustc_short_optgroups()
787 let mut options = getopts::Options::new();
788 for option in groups.iter().filter(|x| include_unstable_options || x.is_stable()) {
789 (option.apply)(&mut options);
791 let message = "Usage: rustc [OPTIONS] INPUT";
792 let nightly_help = if nightly_options::is_nightly_build() {
793 "\n -Z help Print unstable compiler options"
797 let verbose_help = if verbose {
800 "\n --help -v Print the full set of options rustc accepts"
802 let at_path = if verbose && nightly_options::is_nightly_build() {
803 " @path Read newline separated options from `path`\n"
807 println!("{options}{at_path}\nAdditional help:
808 -C help Print codegen options
810 Print 'lint' options and default settings{nightly}{verbose}\n",
811 options = options.usage(message),
813 nightly = nightly_help,
814 verbose = verbose_help);
817 fn print_wall_help() {
819 The flag `-Wall` does not exist in `rustc`. Most useful lints are enabled by
820 default. Use `rustc -W help` to see all available lints. It's more common to put
821 warning settings in the crate root using `#![warn(LINT_NAME)]` instead of using
822 the command line flag directly.
826 fn describe_lints(sess: &Session, lint_store: &lint::LintStore, loaded_plugins: bool) {
828 Available lint options:
829 -W <foo> Warn about <foo>
833 -F <foo> Forbid <foo> \
834 (deny <foo> and all attempts to override)
838 fn sort_lints(sess: &Session, lints: Vec<(&'static Lint, bool)>) -> Vec<&'static Lint> {
839 let mut lints: Vec<_> = lints.into_iter().map(|(x, _)| x).collect();
840 // The sort doesn't case-fold but it's doubtful we care.
841 lints.sort_by_cached_key(|x: &&Lint| (x.default_level(sess), x.name));
845 fn sort_lint_groups(lints: Vec<(&'static str, Vec<lint::LintId>, bool)>)
846 -> Vec<(&'static str, Vec<lint::LintId>)> {
847 let mut lints: Vec<_> = lints.into_iter().map(|(x, y, _)| (x, y)).collect();
848 lints.sort_by_key(|l| l.0);
852 let (plugin, builtin): (Vec<_>, _) = lint_store.get_lints()
855 .partition(|&(_, p)| p);
856 let plugin = sort_lints(sess, plugin);
857 let builtin = sort_lints(sess, builtin);
859 let (plugin_groups, builtin_groups): (Vec<_>, _) = lint_store.get_lint_groups()
862 .partition(|&(.., p)| p);
863 let plugin_groups = sort_lint_groups(plugin_groups);
864 let builtin_groups = sort_lint_groups(builtin_groups);
866 let max_name_len = plugin.iter()
868 .map(|&s| s.name.chars().count())
871 let padded = |x: &str| {
872 let mut s = " ".repeat(max_name_len - x.chars().count());
877 println!("Lint checks provided by rustc:\n");
878 println!(" {} {:7.7} {}", padded("name"), "default", "meaning");
879 println!(" {} {:7.7} {}", padded("----"), "-------", "-------");
881 let print_lints = |lints: Vec<&Lint>| {
883 let name = lint.name_lower().replace("_", "-");
884 println!(" {} {:7.7} {}",
886 lint.default_level.as_str(),
892 print_lints(builtin);
894 let max_name_len = max("warnings".len(),
896 .chain(&builtin_groups)
897 .map(|&(s, _)| s.chars().count())
901 let padded = |x: &str| {
902 let mut s = " ".repeat(max_name_len - x.chars().count());
907 println!("Lint groups provided by rustc:\n");
908 println!(" {} {}", padded("name"), "sub-lints");
909 println!(" {} {}", padded("----"), "---------");
910 println!(" {} {}", padded("warnings"), "all lints that are set to issue warnings");
912 let print_lint_groups = |lints: Vec<(&'static str, Vec<lint::LintId>)>| {
913 for (name, to) in lints {
914 let name = name.to_lowercase().replace("_", "-");
915 let desc = to.into_iter()
916 .map(|x| x.to_string().replace("_", "-"))
917 .collect::<Vec<String>>()
919 println!(" {} {}", padded(&name), desc);
924 print_lint_groups(builtin_groups);
926 match (loaded_plugins, plugin.len(), plugin_groups.len()) {
927 (false, 0, _) | (false, _, 0) => {
928 println!("Compiler plugins can provide additional lints and lint groups. To see a \
929 listing of these, re-run `rustc -W help` with a crate filename.");
931 (false, ..) => panic!("didn't load lint plugins but got them anyway!"),
932 (true, 0, 0) => println!("This crate does not load any lint plugins or lint groups."),
935 println!("Lint checks provided by plugins loaded by this crate:\n");
939 println!("Lint groups provided by plugins loaded by this crate:\n");
940 print_lint_groups(plugin_groups);
946 fn describe_debug_flags() {
947 println!("\nAvailable options:\n");
948 print_flag_list("-Z", config::DB_OPTIONS);
951 fn describe_codegen_flags() {
952 println!("\nAvailable codegen options:\n");
953 print_flag_list("-C", config::CG_OPTIONS);
956 fn print_flag_list<T>(cmdline_opt: &str,
957 flag_list: &[(&'static str, T, Option<&'static str>, &'static str)]) {
958 let max_len = flag_list.iter()
959 .map(|&(name, _, opt_type_desc, _)| {
960 let extra_len = match opt_type_desc {
964 name.chars().count() + extra_len
969 for &(name, _, opt_type_desc, desc) in flag_list {
970 let (width, extra) = match opt_type_desc {
971 Some(..) => (max_len - 4, "=val"),
972 None => (max_len, ""),
974 println!(" {} {:>width$}{} -- {}",
976 name.replace("_", "-"),
983 /// Process command line options. Emits messages as appropriate. If compilation
984 /// should continue, returns a getopts::Matches object parsed from args,
985 /// otherwise returns `None`.
987 /// The compiler's handling of options is a little complicated as it ties into
988 /// our stability story. The current intention of each compiler option is to
989 /// have one of two modes:
991 /// 1. An option is stable and can be used everywhere.
992 /// 2. An option is unstable, and can only be used on nightly.
994 /// Like unstable library and language features, however, unstable options have
995 /// always required a form of "opt in" to indicate that you're using them. This
996 /// provides the easy ability to scan a code base to check to see if anything
997 /// unstable is being used. Currently, this "opt in" is the `-Z` "zed" flag.
999 /// All options behind `-Z` are considered unstable by default. Other top-level
1000 /// options can also be considered unstable, and they were unlocked through the
1001 /// `-Z unstable-options` flag. Note that `-Z` remains to be the root of
1002 /// instability in both cases, though.
1004 /// So with all that in mind, the comments below have some more detail about the
1005 /// contortions done here to get things to work out correctly.
1006 pub fn handle_options(args: &[String]) -> Option<getopts::Matches> {
1007 // Throw away the first argument, the name of the binary
1008 let args = &args[1..];
1010 if args.is_empty() {
1011 // user did not write `-v` nor `-Z unstable-options`, so do not
1012 // include that extra information.
1013 usage(false, false);
1017 // Parse with *all* options defined in the compiler, we don't worry about
1018 // option stability here we just want to parse as much as possible.
1019 let mut options = getopts::Options::new();
1020 for option in config::rustc_optgroups() {
1021 (option.apply)(&mut options);
1023 let matches = options.parse(args).unwrap_or_else(|f|
1024 early_error(ErrorOutputType::default(), &f.to_string()));
1026 // For all options we just parsed, we check a few aspects:
1028 // * If the option is stable, we're all good
1029 // * If the option wasn't passed, we're all good
1030 // * If `-Z unstable-options` wasn't passed (and we're not a -Z option
1031 // ourselves), then we require the `-Z unstable-options` flag to unlock
1032 // this option that was passed.
1033 // * If we're a nightly compiler, then unstable options are now unlocked, so
1034 // we're good to go.
1035 // * Otherwise, if we're an unstable option then we generate an error
1036 // (unstable option being used on stable)
1037 nightly_options::check_nightly_options(&matches, &config::rustc_optgroups());
1039 // Late check to see if @file was used without unstable options enabled
1040 if crate::args::used_unstable_argsfile() && !nightly_options::is_unstable_enabled(&matches) {
1041 early_error(ErrorOutputType::default(),
1042 "@path is unstable - use -Z unstable-options to enable its use");
1045 if matches.opt_present("h") || matches.opt_present("help") {
1046 // Only show unstable options in --help if we accept unstable options.
1047 usage(matches.opt_present("verbose"), nightly_options::is_unstable_enabled(&matches));
1051 // Handle the special case of -Wall.
1052 let wall = matches.opt_strs("W");
1053 if wall.iter().any(|x| *x == "all") {
1058 // Don't handle -W help here, because we might first load plugins.
1059 let r = matches.opt_strs("Z");
1060 if r.iter().any(|x| *x == "help") {
1061 describe_debug_flags();
1065 let cg_flags = matches.opt_strs("C");
1067 if cg_flags.iter().any(|x| *x == "help") {
1068 describe_codegen_flags();
1072 if cg_flags.iter().any(|x| *x == "no-stack-check") {
1073 early_warn(ErrorOutputType::default(),
1074 "the --no-stack-check flag is deprecated and does nothing");
1077 if cg_flags.iter().any(|x| *x == "passes=list") {
1078 get_codegen_sysroot("llvm")().print_passes();
1082 if matches.opt_present("version") {
1083 version("rustc", &matches);
1090 fn parse_crate_attrs<'a>(sess: &'a Session, input: &Input) -> PResult<'a, Vec<ast::Attribute>> {
1092 Input::File(ref ifile) => {
1093 parse::parse_crate_attrs_from_file(ifile, &sess.parse_sess)
1095 Input::Str { ref name, ref input } => {
1096 parse::parse_crate_attrs_from_source_str(name.clone(),
1103 /// Gets a list of extra command-line flags provided by the user, as strings.
1105 /// This function is used during ICEs to show more information useful for
1106 /// debugging, since some ICEs only happens with non-default compiler flags
1107 /// (and the users don't always report them).
1108 fn extra_compiler_flags() -> Option<(Vec<String>, bool)> {
1109 let args = env::args_os().map(|arg| arg.to_string_lossy().to_string()).collect::<Vec<_>>();
1111 // Avoid printing help because of empty args. This can suggest the compiler
1112 // itself is not the program root (consider RLS).
1117 let matches = if let Some(matches) = handle_options(&args) {
1123 let mut result = Vec::new();
1124 let mut excluded_cargo_defaults = false;
1125 for flag in ICE_REPORT_COMPILER_FLAGS {
1126 let prefix = if flag.len() == 1 { "-" } else { "--" };
1128 for content in &matches.opt_strs(flag) {
1129 // Split always returns the first element
1130 let name = if let Some(first) = content.split('=').next() {
1136 let content = if ICE_REPORT_COMPILER_FLAGS_STRIP_VALUE.contains(&name) {
1142 if !ICE_REPORT_COMPILER_FLAGS_EXCLUDE.contains(&name) {
1143 result.push(format!("{}{} {}", prefix, flag, content));
1145 excluded_cargo_defaults = true;
1150 if !result.is_empty() {
1151 Some((result, excluded_cargo_defaults))
1157 /// Runs a closure and catches unwinds triggered by fatal errors.
1159 /// The compiler currently unwinds with a special sentinel value to abort
1160 /// compilation on fatal errors. This function catches that sentinel and turns
1161 /// the panic into a `Result` instead.
1162 pub fn catch_fatal_errors<F: FnOnce() -> R, R>(f: F) -> Result<R, ErrorReported> {
1163 catch_unwind(panic::AssertUnwindSafe(f)).map_err(|value| {
1164 if value.is::<errors::FatalErrorMarker>() {
1167 panic::resume_unwind(value);
1173 static ref DEFAULT_HOOK: Box<dyn Fn(&panic::PanicInfo<'_>) + Sync + Send + 'static> = {
1174 let hook = panic::take_hook();
1175 panic::set_hook(Box::new(|info| report_ice(info, BUG_REPORT_URL)));
1180 /// Prints the ICE message, including backtrace and query stack.
1182 /// The message will point the user at `bug_report_url` to report the ICE.
1184 /// When `install_ice_hook` is called, this function will be called as the panic
1186 pub fn report_ice(info: &panic::PanicInfo<'_>, bug_report_url: &str) {
1187 // Invoke the default handler, which prints the actual panic message and optionally a backtrace
1188 (*DEFAULT_HOOK)(info);
1190 // Separate the output with an empty line
1193 let emitter = Box::new(errors::emitter::EmitterWriter::stderr(
1194 errors::ColorConfig::Auto,
1201 let handler = errors::Handler::with_emitter(true, None, emitter);
1203 // a .span_bug or .bug call has already printed what
1204 // it wants to print.
1205 if !info.payload().is::<errors::ExplicitBug>() {
1206 let d = errors::Diagnostic::new(errors::Level::Bug, "unexpected panic");
1207 handler.emit_diagnostic(&d);
1208 handler.abort_if_errors_and_should_abort();
1211 let mut xs: Vec<Cow<'static, str>> = vec![
1212 "the compiler unexpectedly panicked. this is a bug.".into(),
1213 format!("we would appreciate a bug report: {}", bug_report_url).into(),
1214 format!("rustc {} running on {}",
1215 option_env!("CFG_VERSION").unwrap_or("unknown_version"),
1216 config::host_triple()).into(),
1219 if let Some((flags, excluded_cargo_defaults)) = extra_compiler_flags() {
1220 xs.push(format!("compiler flags: {}", flags.join(" ")).into());
1222 if excluded_cargo_defaults {
1223 xs.push("some of the compiler flags provided by cargo are hidden".into());
1228 handler.note_without_error(¬e);
1231 // If backtraces are enabled, also print the query stack
1232 let backtrace = env::var_os("RUST_BACKTRACE").map(|x| &x != "0").unwrap_or(false);
1235 TyCtxt::try_print_query_stack(&handler);
1240 if env::var("RUSTC_BREAK_ON_ICE").is_ok() {
1244 // Trigger a debugger if we crashed during bootstrap
1250 /// Installs a panic hook that will print the ICE message on unexpected panics.
1252 /// A custom rustc driver can skip calling this to set up a custom ICE hook.
1253 pub fn install_ice_hook() {
1254 lazy_static::initialize(&DEFAULT_HOOK);
1257 /// This allows tools to enable rust logging without having to magically match rustc's
1258 /// log crate version
1259 pub fn init_rustc_env_logger() {
1260 env_logger::init_from_env("RUSTC_LOG");
1264 let start = Instant::now();
1265 init_rustc_env_logger();
1266 let mut callbacks = TimePassesCallbacks::default();
1268 let result = catch_fatal_errors(|| {
1269 let args = env::args_os().enumerate()
1270 .map(|(i, arg)| arg.into_string().unwrap_or_else(|arg| {
1271 early_error(ErrorOutputType::default(),
1272 &format!("Argument {} is not valid Unicode: {:?}", i, arg))
1274 .collect::<Vec<_>>();
1275 run_compiler(&args, &mut callbacks, None, None)
1276 }).and_then(|result| result);
1277 let exit_code = match result {
1278 Ok(_) => EXIT_SUCCESS,
1279 Err(_) => EXIT_FAILURE,
1281 // The extra `\t` is necessary to align this label with the others.
1283 print_time_passes_entry(callbacks.time_passes, "\ttotal", start.elapsed());
1284 process::exit(exit_code);