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;
44 use rustc_interface::interface;
45 use rustc_interface::util::get_codegen_sysroot;
46 use rustc_data_structures::sync::SeqCst;
48 use rustc_serialize::json::ToJson;
52 use std::default::Default;
54 use std::ffi::OsString;
55 use std::io::{self, Read, Write};
57 use std::panic::{self, catch_unwind};
58 use std::path::PathBuf;
59 use std::process::{self, Command, Stdio};
61 use std::time::Instant;
64 use syntax::source_map::FileLoader;
65 use syntax::feature_gate::{GatedCfg, UnstableFeatures};
66 use syntax::symbol::sym;
67 use syntax_pos::{DUMMY_SP, FileName};
72 /// Exit status code used for successful compilation and help output.
73 pub const EXIT_SUCCESS: i32 = 0;
75 /// Exit status code used for compilation failures and invalid flags.
76 pub const EXIT_FAILURE: i32 = 1;
78 const BUG_REPORT_URL: &str = "https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.\
81 const ICE_REPORT_COMPILER_FLAGS: &[&str] = &["Z", "C", "crate-type"];
83 const ICE_REPORT_COMPILER_FLAGS_EXCLUDE: &[&str] = &["metadata", "extra-filename"];
85 const ICE_REPORT_COMPILER_FLAGS_STRIP_VALUE: &[&str] = &["incremental"];
87 pub fn source_name(input: &Input) -> FileName {
89 Input::File(ref ifile) => ifile.clone().into(),
90 Input::Str { ref name, .. } => name.clone(),
94 pub fn abort_on_err<T>(result: Result<T, ErrorReported>, sess: &Session) -> T {
97 sess.abort_if_errors();
98 panic!("error reported but abort_if_errors didn't abort???");
104 pub trait Callbacks {
105 /// Called before creating the compiler instance
106 fn config(&mut self, _config: &mut interface::Config) {}
107 /// Called after parsing. Return value instructs the compiler whether to
108 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
109 fn after_parsing(&mut self, _compiler: &interface::Compiler) -> Compilation {
110 Compilation::Continue
112 /// Called after expansion. Return value instructs the compiler whether to
113 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
114 fn after_expansion(&mut self, _compiler: &interface::Compiler) -> Compilation {
115 Compilation::Continue
117 /// Called after analysis. Return value instructs the compiler whether to
118 /// continue the compilation afterwards (defaults to `Compilation::Continue`)
119 fn after_analysis(&mut self, _compiler: &interface::Compiler) -> Compilation {
120 Compilation::Continue
124 pub struct DefaultCallbacks;
126 impl Callbacks for DefaultCallbacks {}
129 pub struct TimePassesCallbacks {
133 impl Callbacks for TimePassesCallbacks {
134 fn config(&mut self, config: &mut interface::Config) {
135 // If a --prints=... option has been given, we don't print the "total"
136 // time because it will mess up the --prints output. See #64339.
138 config.opts.prints.is_empty() &&
139 (config.opts.debugging_opts.time_passes || config.opts.debugging_opts.time);
143 // Parse args and run the compiler. This is the primary entry point for rustc.
144 // See comments on CompilerCalls below for details about the callbacks argument.
145 // The FileLoader provides a way to load files from sources other than the file system.
148 callbacks: &mut (dyn Callbacks + Send),
149 file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
150 emitter: Option<Box<dyn Write + Send>>
151 ) -> interface::Result<()> {
152 let mut args = Vec::new();
154 match args::arg_expand(arg.clone()) {
155 Ok(arg) => args.extend(arg),
156 Err(err) => early_error(ErrorOutputType::default(),
157 &format!("Failed to load argument file: {}", err)),
160 let diagnostic_output = emitter.map(|emitter| DiagnosticOutput::Raw(emitter))
161 .unwrap_or(DiagnosticOutput::Default);
162 let matches = match handle_options(&args) {
163 Some(matches) => matches,
164 None => return Ok(()),
167 let sopts = config::build_session_options(&matches);
168 let cfg = interface::parse_cfgspecs(matches.opt_strs("cfg"));
170 let mut dummy_config = |sopts, cfg, diagnostic_output| {
171 let mut config = interface::Config {
174 input: Input::File(PathBuf::new()),
182 lint_caps: Default::default(),
183 register_lints: None,
184 override_queries: None,
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 {
205 let lint_store = rustc_lint::new_lint_store(
206 sopts.debugging_opts.no_interleave_lints,
207 compiler.session().unstable_options(),
216 let should_stop = RustcDefaultCalls::print_crate_info(
217 &***compiler.codegen_backend(),
224 if should_stop == Compilation::Stop {
227 early_error(sopts.error_format, "no input filename given")
231 1 => panic!("make_input should have provided valid inputs"),
232 _ => early_error(sopts.error_format, &format!(
233 "multiple input filenames provided (first two filenames are `{}` and `{}`)",
241 if let Some(err) = input_err {
242 // Immediately stop compilation if there was an issue reading
243 // the input (for example if the input stream is not UTF-8).
244 interface::run_compiler(dummy_config(sopts, cfg, diagnostic_output), |compiler| {
245 compiler.session().err(&err.to_string());
247 return Err(ErrorReported);
250 let mut config = interface::Config {
254 input_path: input_file_path,
261 lint_caps: Default::default(),
262 register_lints: None,
263 override_queries: None,
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, opt_uii)) = &sess.opts.pretty {
290 if ppm.needs_ast_map(&opt_uii) {
291 compiler.global_ctxt()?.peek_mut().enter(|tcx| {
292 let expanded_crate = compiler.expansion()?.take().0;
293 pretty::print_after_hir_lowering(
299 compiler.output_file().as_ref().map(|p| &**p),
304 let krate = compiler.parse()?.take();
305 pretty::print_after_parsing(
310 compiler.output_file().as_ref().map(|p| &**p),
313 return sess.compile_status();
316 if callbacks.after_parsing(compiler) == Compilation::Stop {
317 return sess.compile_status();
320 if sess.opts.debugging_opts.parse_only ||
321 sess.opts.debugging_opts.show_span.is_some() ||
322 sess.opts.debugging_opts.ast_json_noexpand {
323 return sess.compile_status();
327 let (_, _, lint_store) = &*compiler.register_plugins()?.peek();
329 // Lint plugins are registered; now we can process command line flags.
330 if sess.opts.describe_lints {
331 describe_lints(&sess, &lint_store, true);
332 return sess.compile_status();
336 compiler.expansion()?;
337 if callbacks.after_expansion(compiler) == Compilation::Stop {
338 return sess.compile_status();
341 compiler.prepare_outputs()?;
343 if sess.opts.output_types.contains_key(&OutputType::DepInfo)
344 && sess.opts.output_types.len() == 1
346 return sess.compile_status();
349 compiler.global_ctxt()?;
351 if sess.opts.debugging_opts.no_analysis ||
352 sess.opts.debugging_opts.ast_json {
353 return sess.compile_status();
356 if sess.opts.debugging_opts.save_analysis {
357 let expanded_crate = &compiler.expansion()?.peek().0;
358 let crate_name = compiler.crate_name()?.peek().clone();
359 compiler.global_ctxt()?.peek_mut().enter(|tcx| {
360 let result = tcx.analysis(LOCAL_CRATE);
362 time(sess, "save analysis", || {
369 DumpHandler::new(compiler.output_dir().as_ref().map(|p| &**p), &crate_name)
374 // AST will be dropped *after* the `after_analysis` callback
375 // (needed by the RLS)
378 // Drop AST after creating GlobalCtxt to free memory
379 mem::drop(compiler.expansion()?.take());
382 compiler.global_ctxt()?.peek_mut().enter(|tcx| tcx.analysis(LOCAL_CRATE))?;
384 if callbacks.after_analysis(compiler) == Compilation::Stop {
385 return sess.compile_status();
388 if sess.opts.debugging_opts.save_analysis {
389 mem::drop(compiler.expansion()?.take());
392 compiler.ongoing_codegen()?;
394 // Drop GlobalCtxt after starting codegen to free memory
395 mem::drop(compiler.global_ctxt()?.take());
397 if sess.opts.debugging_opts.print_type_sizes {
398 sess.code_stats.print_type_sizes();
403 if sess.opts.debugging_opts.perf_stats {
404 sess.print_perf_stats();
407 if sess.print_fuel_crate.is_some() {
408 eprintln!("Fuel used by {}: {}",
409 sess.print_fuel_crate.as_ref().unwrap(),
410 sess.print_fuel.load(SeqCst));
418 pub fn set_sigpipe_handler() {
420 // Set the SIGPIPE signal handler, so that an EPIPE
421 // will cause rustc to terminate, as expected.
422 assert_ne!(libc::signal(libc::SIGPIPE, libc::SIG_DFL), libc::SIG_ERR);
427 pub fn set_sigpipe_handler() {}
429 // Extract output directory and file from matches.
430 fn make_output(matches: &getopts::Matches) -> (Option<PathBuf>, Option<PathBuf>) {
431 let odir = matches.opt_str("out-dir").map(|o| PathBuf::from(&o));
432 let ofile = matches.opt_str("o").map(|o| PathBuf::from(&o));
436 // Extract input (string or file and optional path) from matches.
437 fn make_input(free_matches: &[String]) -> Option<(Input, Option<PathBuf>, Option<io::Error>)> {
438 if free_matches.len() == 1 {
439 let ifile = &free_matches[0];
441 let mut src = String::new();
442 let err = if io::stdin().read_to_string(&mut src).is_err() {
443 Some(io::Error::new(io::ErrorKind::InvalidData,
444 "couldn't read from stdin, as it did not contain valid UTF-8"))
448 if let Ok(path) = env::var("UNSTABLE_RUSTDOC_TEST_PATH") {
449 let line = env::var("UNSTABLE_RUSTDOC_TEST_LINE").
450 expect("when UNSTABLE_RUSTDOC_TEST_PATH is set \
451 UNSTABLE_RUSTDOC_TEST_LINE also needs to be set");
452 let line = isize::from_str_radix(&line, 10).
453 expect("UNSTABLE_RUSTDOC_TEST_LINE needs to be an number");
454 let file_name = FileName::doc_test_source_code(PathBuf::from(path), line);
455 return Some((Input::Str { name: file_name, input: src }, None, err));
457 Some((Input::Str { name: FileName::anon_source_code(&src), input: src },
460 Some((Input::File(PathBuf::from(ifile)),
461 Some(PathBuf::from(ifile)), None))
468 // Whether to stop or continue compilation.
469 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
470 pub enum Compilation {
476 pub fn and_then<F: FnOnce() -> Compilation>(self, next: F) -> Compilation {
478 Compilation::Stop => Compilation::Stop,
479 Compilation::Continue => next(),
484 /// CompilerCalls instance for a regular rustc build.
485 #[derive(Copy, Clone)]
486 pub struct RustcDefaultCalls;
488 // FIXME remove these and use winapi 0.3 instead
489 // Duplicates: bootstrap/compile.rs, librustc_errors/emitter.rs
491 fn stdout_isatty() -> bool {
492 unsafe { libc::isatty(libc::STDOUT_FILENO) != 0 }
496 fn stdout_isatty() -> bool {
499 type HANDLE = *mut u8;
500 type LPDWORD = *mut u32;
501 const STD_OUTPUT_HANDLE: DWORD = -11i32 as DWORD;
503 fn GetStdHandle(which: DWORD) -> HANDLE;
504 fn GetConsoleMode(hConsoleHandle: HANDLE, lpMode: LPDWORD) -> BOOL;
507 let handle = GetStdHandle(STD_OUTPUT_HANDLE);
509 GetConsoleMode(handle, &mut out) != 0
513 fn handle_explain(code: &str,
514 output: ErrorOutputType) {
515 let descriptions = rustc_interface::util::diagnostics_registry();
516 let normalised = if code.starts_with("E") {
519 format!("E{0:0>4}", code)
521 match descriptions.find_description(&normalised) {
522 Some(ref description) => {
523 let mut is_in_code_block = false;
524 let mut text = String::new();
526 // Slice off the leading newline and print.
527 for line in description.lines() {
528 let indent_level = line.find(|c: char| !c.is_whitespace())
529 .unwrap_or_else(|| line.len());
530 let dedented_line = &line[indent_level..];
531 if dedented_line.starts_with("```") {
532 is_in_code_block = !is_in_code_block;
533 text.push_str(&line[..(indent_level + 3)]);
534 } else if is_in_code_block && dedented_line.starts_with("# ") {
543 show_content_with_pager(&text);
549 early_error(output, &format!("no extended information for {}", code));
554 fn show_content_with_pager(content: &String) {
555 let pager_name = env::var_os("PAGER").unwrap_or_else(|| if cfg!(windows) {
556 OsString::from("more.com")
558 OsString::from("less")
561 let mut fallback_to_println = false;
563 match Command::new(pager_name).stdin(Stdio::piped()).spawn() {
565 if let Some(pipe) = pager.stdin.as_mut() {
566 if pipe.write_all(content.as_bytes()).is_err() {
567 fallback_to_println = true;
571 if pager.wait().is_err() {
572 fallback_to_println = true;
576 fallback_to_println = true;
580 // If pager fails for whatever reason, we should still print the content
581 // to standard output
582 if fallback_to_println {
583 print!("{}", content);
587 impl RustcDefaultCalls {
588 pub fn list_metadata(sess: &Session,
589 metadata_loader: &dyn MetadataLoader,
590 matches: &getopts::Matches,
593 let r = matches.opt_strs("Z");
594 if r.iter().any(|s| *s == "ls") {
596 &Input::File(ref ifile) => {
597 let path = &(*ifile);
598 let mut v = Vec::new();
599 locator::list_file_metadata(&sess.target.target,
604 println!("{}", String::from_utf8(v).unwrap());
606 &Input::Str { .. } => {
607 early_error(ErrorOutputType::default(), "cannot list metadata for stdin");
610 return Compilation::Stop;
613 Compilation::Continue
617 fn print_crate_info(codegen_backend: &dyn CodegenBackend,
619 input: Option<&Input>,
620 odir: &Option<PathBuf>,
621 ofile: &Option<PathBuf>)
623 use rustc::session::config::PrintRequest::*;
624 // PrintRequest::NativeStaticLibs is special - printed during linking
625 // (empty iterator returns true)
626 if sess.opts.prints.iter().all(|&p| p == PrintRequest::NativeStaticLibs) {
627 return Compilation::Continue;
630 let attrs = match input {
633 let result = parse_crate_attrs(sess, input);
635 Ok(attrs) => Some(attrs),
636 Err(mut parse_error) => {
638 return Compilation::Stop;
643 for req in &sess.opts.prints {
646 let mut targets = rustc_target::spec::get_targets().collect::<Vec<String>>();
648 println!("{}", targets.join("\n"));
650 Sysroot => println!("{}", sess.sysroot.display()),
651 TargetSpec => println!("{}", sess.target.target.to_json().pretty()),
652 FileNames | CrateName => {
653 let input = input.unwrap_or_else(||
654 early_error(ErrorOutputType::default(), "no input file provided"));
655 let attrs = attrs.as_ref().unwrap();
656 let t_outputs = rustc_interface::util::build_output_filenames(
663 let id = rustc_codegen_utils::link::find_crate_name(Some(sess), attrs, input);
664 if *req == PrintRequest::CrateName {
668 let crate_types = rustc_interface::util::collect_crate_types(sess, attrs);
669 for &style in &crate_types {
670 let fname = rustc_codegen_utils::link::filename_for_input(
676 println!("{}", fname.file_name().unwrap().to_string_lossy());
680 let allow_unstable_cfg = UnstableFeatures::from_environment()
683 let mut cfgs = sess.parse_sess.config.iter().filter_map(|&(name, ref value)| {
684 let gated_cfg = GatedCfg::gate(&ast::MetaItem {
685 path: ast::Path::from_ident(ast::Ident::with_dummy_span(name)),
686 kind: ast::MetaItemKind::Word,
690 // Note that crt-static is a specially recognized cfg
691 // directive that's printed out here as part of
692 // rust-lang/rust#37406, but in general the
693 // `target_feature` cfg is gated under
694 // rust-lang/rust#29717. For now this is just
695 // specifically allowing the crt-static cfg and that's
696 // it, this is intended to get into Cargo and then go
697 // through to build scripts.
698 let value = value.as_ref().map(|s| s.as_str());
699 let value = value.as_ref().map(|s| s.as_ref());
700 if name != sym::target_feature || value != Some("crt-static") {
701 if !allow_unstable_cfg && gated_cfg.is_some() {
706 if let Some(value) = value {
707 Some(format!("{}=\"{}\"", name, value))
709 Some(name.to_string())
711 }).collect::<Vec<String>>();
718 RelocationModels | CodeModels | TlsModels | TargetCPUs | TargetFeatures => {
719 codegen_backend.print(*req, sess);
721 // Any output here interferes with Cargo's parsing of other printed output
722 PrintRequest::NativeStaticLibs => {}
725 return Compilation::Stop;
729 /// Returns a version string such as "0.12.0-dev".
730 fn release_str() -> Option<&'static str> {
731 option_env!("CFG_RELEASE")
734 /// Returns the full SHA1 hash of HEAD of the Git repo from which rustc was built.
735 fn commit_hash_str() -> Option<&'static str> {
736 option_env!("CFG_VER_HASH")
739 /// Returns the "commit date" of HEAD of the Git repo from which rustc was built as a static string.
740 fn commit_date_str() -> Option<&'static str> {
741 option_env!("CFG_VER_DATE")
744 /// Prints version information
745 pub fn version(binary: &str, matches: &getopts::Matches) {
746 let verbose = matches.opt_present("verbose");
748 println!("{} {}", binary, option_env!("CFG_VERSION").unwrap_or("unknown version"));
751 fn unw(x: Option<&str>) -> &str {
752 x.unwrap_or("unknown")
754 println!("binary: {}", binary);
755 println!("commit-hash: {}", unw(commit_hash_str()));
756 println!("commit-date: {}", unw(commit_date_str()));
757 println!("host: {}", config::host_triple());
758 println!("release: {}", unw(release_str()));
759 get_codegen_sysroot("llvm")().print_version();
763 fn usage(verbose: bool, include_unstable_options: bool) {
764 let groups = if verbose {
765 config::rustc_optgroups()
767 config::rustc_short_optgroups()
769 let mut options = getopts::Options::new();
770 for option in groups.iter().filter(|x| include_unstable_options || x.is_stable()) {
771 (option.apply)(&mut options);
773 let message = "Usage: rustc [OPTIONS] INPUT";
774 let nightly_help = if nightly_options::is_nightly_build() {
775 "\n -Z help Print unstable compiler options"
779 let verbose_help = if verbose {
782 "\n --help -v Print the full set of options rustc accepts"
784 let at_path = if verbose && nightly_options::is_nightly_build() {
785 " @path Read newline separated options from `path`\n"
789 println!("{options}{at_path}\nAdditional help:
790 -C help Print codegen options
792 Print 'lint' options and default settings{nightly}{verbose}\n",
793 options = options.usage(message),
795 nightly = nightly_help,
796 verbose = verbose_help);
799 fn print_wall_help() {
801 The flag `-Wall` does not exist in `rustc`. Most useful lints are enabled by
802 default. Use `rustc -W help` to see all available lints. It's more common to put
803 warning settings in the crate root using `#![warn(LINT_NAME)]` instead of using
804 the command line flag directly.
808 fn describe_lints(sess: &Session, lint_store: &lint::LintStore, loaded_plugins: bool) {
810 Available lint options:
811 -W <foo> Warn about <foo>
815 -F <foo> Forbid <foo> \
816 (deny <foo> and all attempts to override)
820 fn sort_lints(sess: &Session, mut lints: Vec<&'static Lint>) -> Vec<&'static Lint> {
821 // The sort doesn't case-fold but it's doubtful we care.
822 lints.sort_by_cached_key(|x: &&Lint| (x.default_level(sess), x.name));
826 fn sort_lint_groups(lints: Vec<(&'static str, Vec<lint::LintId>, bool)>)
827 -> Vec<(&'static str, Vec<lint::LintId>)> {
828 let mut lints: Vec<_> = lints.into_iter().map(|(x, y, _)| (x, y)).collect();
829 lints.sort_by_key(|l| l.0);
833 let (plugin, builtin): (Vec<_>, _) = lint_store.get_lints()
836 .partition(|&lint| lint.is_plugin);
837 let plugin = sort_lints(sess, plugin);
838 let builtin = sort_lints(sess, builtin);
840 let (plugin_groups, builtin_groups): (Vec<_>, _) = lint_store.get_lint_groups()
843 .partition(|&(.., p)| p);
844 let plugin_groups = sort_lint_groups(plugin_groups);
845 let builtin_groups = sort_lint_groups(builtin_groups);
847 let max_name_len = plugin.iter()
849 .map(|&s| s.name.chars().count())
852 let padded = |x: &str| {
853 let mut s = " ".repeat(max_name_len - x.chars().count());
858 println!("Lint checks provided by rustc:\n");
859 println!(" {} {:7.7} {}", padded("name"), "default", "meaning");
860 println!(" {} {:7.7} {}", padded("----"), "-------", "-------");
862 let print_lints = |lints: Vec<&Lint>| {
864 let name = lint.name_lower().replace("_", "-");
865 println!(" {} {:7.7} {}",
867 lint.default_level.as_str(),
873 print_lints(builtin);
875 let max_name_len = max("warnings".len(),
877 .chain(&builtin_groups)
878 .map(|&(s, _)| s.chars().count())
882 let padded = |x: &str| {
883 let mut s = " ".repeat(max_name_len - x.chars().count());
888 println!("Lint groups provided by rustc:\n");
889 println!(" {} {}", padded("name"), "sub-lints");
890 println!(" {} {}", padded("----"), "---------");
891 println!(" {} {}", padded("warnings"), "all lints that are set to issue warnings");
893 let print_lint_groups = |lints: Vec<(&'static str, Vec<lint::LintId>)>| {
894 for (name, to) in lints {
895 let name = name.to_lowercase().replace("_", "-");
896 let desc = to.into_iter()
897 .map(|x| x.to_string().replace("_", "-"))
898 .collect::<Vec<String>>()
900 println!(" {} {}", padded(&name), desc);
905 print_lint_groups(builtin_groups);
907 match (loaded_plugins, plugin.len(), plugin_groups.len()) {
908 (false, 0, _) | (false, _, 0) => {
909 println!("Compiler plugins can provide additional lints and lint groups. To see a \
910 listing of these, re-run `rustc -W help` with a crate filename.");
912 (false, ..) => panic!("didn't load lint plugins but got them anyway!"),
913 (true, 0, 0) => println!("This crate does not load any lint plugins or lint groups."),
916 println!("Lint checks provided by plugins loaded by this crate:\n");
920 println!("Lint groups provided by plugins loaded by this crate:\n");
921 print_lint_groups(plugin_groups);
927 fn describe_debug_flags() {
928 println!("\nAvailable options:\n");
929 print_flag_list("-Z", config::DB_OPTIONS);
932 fn describe_codegen_flags() {
933 println!("\nAvailable codegen options:\n");
934 print_flag_list("-C", config::CG_OPTIONS);
937 fn print_flag_list<T>(cmdline_opt: &str,
938 flag_list: &[(&'static str, T, Option<&'static str>, &'static str)]) {
939 let max_len = flag_list.iter()
940 .map(|&(name, _, opt_type_desc, _)| {
941 let extra_len = match opt_type_desc {
945 name.chars().count() + extra_len
950 for &(name, _, opt_type_desc, desc) in flag_list {
951 let (width, extra) = match opt_type_desc {
952 Some(..) => (max_len - 4, "=val"),
953 None => (max_len, ""),
955 println!(" {} {:>width$}{} -- {}",
957 name.replace("_", "-"),
964 /// Process command line options. Emits messages as appropriate. If compilation
965 /// should continue, returns a getopts::Matches object parsed from args,
966 /// otherwise returns `None`.
968 /// The compiler's handling of options is a little complicated as it ties into
969 /// our stability story. The current intention of each compiler option is to
970 /// have one of two modes:
972 /// 1. An option is stable and can be used everywhere.
973 /// 2. An option is unstable, and can only be used on nightly.
975 /// Like unstable library and language features, however, unstable options have
976 /// always required a form of "opt in" to indicate that you're using them. This
977 /// provides the easy ability to scan a code base to check to see if anything
978 /// unstable is being used. Currently, this "opt in" is the `-Z` "zed" flag.
980 /// All options behind `-Z` are considered unstable by default. Other top-level
981 /// options can also be considered unstable, and they were unlocked through the
982 /// `-Z unstable-options` flag. Note that `-Z` remains to be the root of
983 /// instability in both cases, though.
985 /// So with all that in mind, the comments below have some more detail about the
986 /// contortions done here to get things to work out correctly.
987 pub fn handle_options(args: &[String]) -> Option<getopts::Matches> {
988 // Throw away the first argument, the name of the binary
989 let args = &args[1..];
992 // user did not write `-v` nor `-Z unstable-options`, so do not
993 // include that extra information.
998 // Parse with *all* options defined in the compiler, we don't worry about
999 // option stability here we just want to parse as much as possible.
1000 let mut options = getopts::Options::new();
1001 for option in config::rustc_optgroups() {
1002 (option.apply)(&mut options);
1004 let matches = options.parse(args).unwrap_or_else(|f|
1005 early_error(ErrorOutputType::default(), &f.to_string()));
1007 // For all options we just parsed, we check a few aspects:
1009 // * If the option is stable, we're all good
1010 // * If the option wasn't passed, we're all good
1011 // * If `-Z unstable-options` wasn't passed (and we're not a -Z option
1012 // ourselves), then we require the `-Z unstable-options` flag to unlock
1013 // this option that was passed.
1014 // * If we're a nightly compiler, then unstable options are now unlocked, so
1015 // we're good to go.
1016 // * Otherwise, if we're an unstable option then we generate an error
1017 // (unstable option being used on stable)
1018 nightly_options::check_nightly_options(&matches, &config::rustc_optgroups());
1020 if matches.opt_present("h") || matches.opt_present("help") {
1021 // Only show unstable options in --help if we accept unstable options.
1022 usage(matches.opt_present("verbose"), nightly_options::is_unstable_enabled(&matches));
1026 // Handle the special case of -Wall.
1027 let wall = matches.opt_strs("W");
1028 if wall.iter().any(|x| *x == "all") {
1033 // Don't handle -W help here, because we might first load plugins.
1034 let r = matches.opt_strs("Z");
1035 if r.iter().any(|x| *x == "help") {
1036 describe_debug_flags();
1040 let cg_flags = matches.opt_strs("C");
1042 if cg_flags.iter().any(|x| *x == "help") {
1043 describe_codegen_flags();
1047 if cg_flags.iter().any(|x| *x == "no-stack-check") {
1048 early_warn(ErrorOutputType::default(),
1049 "the --no-stack-check flag is deprecated and does nothing");
1052 if cg_flags.iter().any(|x| *x == "passes=list") {
1053 get_codegen_sysroot("llvm")().print_passes();
1057 if matches.opt_present("version") {
1058 version("rustc", &matches);
1065 fn parse_crate_attrs<'a>(sess: &'a Session, input: &Input) -> PResult<'a, Vec<ast::Attribute>> {
1067 Input::File(ifile) => {
1068 rustc_parse::parse_crate_attrs_from_file(ifile, &sess.parse_sess)
1070 Input::Str { name, input } => {
1071 rustc_parse::parse_crate_attrs_from_source_str(
1080 /// Gets a list of extra command-line flags provided by the user, as strings.
1082 /// This function is used during ICEs to show more information useful for
1083 /// debugging, since some ICEs only happens with non-default compiler flags
1084 /// (and the users don't always report them).
1085 fn extra_compiler_flags() -> Option<(Vec<String>, bool)> {
1086 let args = env::args_os().map(|arg| arg.to_string_lossy().to_string()).collect::<Vec<_>>();
1088 // Avoid printing help because of empty args. This can suggest the compiler
1089 // itself is not the program root (consider RLS).
1094 let matches = if let Some(matches) = handle_options(&args) {
1100 let mut result = Vec::new();
1101 let mut excluded_cargo_defaults = false;
1102 for flag in ICE_REPORT_COMPILER_FLAGS {
1103 let prefix = if flag.len() == 1 { "-" } else { "--" };
1105 for content in &matches.opt_strs(flag) {
1106 // Split always returns the first element
1107 let name = if let Some(first) = content.split('=').next() {
1113 let content = if ICE_REPORT_COMPILER_FLAGS_STRIP_VALUE.contains(&name) {
1119 if !ICE_REPORT_COMPILER_FLAGS_EXCLUDE.contains(&name) {
1120 result.push(format!("{}{} {}", prefix, flag, content));
1122 excluded_cargo_defaults = true;
1127 if !result.is_empty() {
1128 Some((result, excluded_cargo_defaults))
1134 /// Runs a closure and catches unwinds triggered by fatal errors.
1136 /// The compiler currently unwinds with a special sentinel value to abort
1137 /// compilation on fatal errors. This function catches that sentinel and turns
1138 /// the panic into a `Result` instead.
1139 pub fn catch_fatal_errors<F: FnOnce() -> R, R>(f: F) -> Result<R, ErrorReported> {
1140 catch_unwind(panic::AssertUnwindSafe(f)).map_err(|value| {
1141 if value.is::<errors::FatalErrorMarker>() {
1144 panic::resume_unwind(value);
1150 static ref DEFAULT_HOOK: Box<dyn Fn(&panic::PanicInfo<'_>) + Sync + Send + 'static> = {
1151 let hook = panic::take_hook();
1152 panic::set_hook(Box::new(|info| report_ice(info, BUG_REPORT_URL)));
1157 /// Prints the ICE message, including backtrace and query stack.
1159 /// The message will point the user at `bug_report_url` to report the ICE.
1161 /// When `install_ice_hook` is called, this function will be called as the panic
1163 pub fn report_ice(info: &panic::PanicInfo<'_>, bug_report_url: &str) {
1164 // Invoke the default handler, which prints the actual panic message and optionally a backtrace
1165 (*DEFAULT_HOOK)(info);
1167 // Separate the output with an empty line
1170 let emitter = Box::new(errors::emitter::EmitterWriter::stderr(
1171 errors::ColorConfig::Auto,
1178 let handler = errors::Handler::with_emitter(true, None, emitter);
1180 // a .span_bug or .bug call has already printed what
1181 // it wants to print.
1182 if !info.payload().is::<errors::ExplicitBug>() {
1183 let d = errors::Diagnostic::new(errors::Level::Bug, "unexpected panic");
1184 handler.emit_diagnostic(&d);
1185 handler.abort_if_errors_and_should_abort();
1188 let mut xs: Vec<Cow<'static, str>> = vec![
1189 "the compiler unexpectedly panicked. this is a bug.".into(),
1190 format!("we would appreciate a bug report: {}", bug_report_url).into(),
1191 format!("rustc {} running on {}",
1192 option_env!("CFG_VERSION").unwrap_or("unknown_version"),
1193 config::host_triple()).into(),
1196 if let Some((flags, excluded_cargo_defaults)) = extra_compiler_flags() {
1197 xs.push(format!("compiler flags: {}", flags.join(" ")).into());
1199 if excluded_cargo_defaults {
1200 xs.push("some of the compiler flags provided by cargo are hidden".into());
1205 handler.note_without_error(¬e);
1208 // If backtraces are enabled, also print the query stack
1209 let backtrace = env::var_os("RUST_BACKTRACE").map(|x| &x != "0").unwrap_or(false);
1212 TyCtxt::try_print_query_stack(&handler);
1217 if env::var("RUSTC_BREAK_ON_ICE").is_ok() {
1221 // Trigger a debugger if we crashed during bootstrap
1227 /// Installs a panic hook that will print the ICE message on unexpected panics.
1229 /// A custom rustc driver can skip calling this to set up a custom ICE hook.
1230 pub fn install_ice_hook() {
1231 lazy_static::initialize(&DEFAULT_HOOK);
1234 /// This allows tools to enable rust logging without having to magically match rustc's
1235 /// log crate version
1236 pub fn init_rustc_env_logger() {
1237 env_logger::init_from_env("RUSTC_LOG");
1241 let start = Instant::now();
1242 init_rustc_env_logger();
1243 let mut callbacks = TimePassesCallbacks::default();
1245 let result = catch_fatal_errors(|| {
1246 let args = env::args_os().enumerate()
1247 .map(|(i, arg)| arg.into_string().unwrap_or_else(|arg| {
1248 early_error(ErrorOutputType::default(),
1249 &format!("Argument {} is not valid Unicode: {:?}", i, arg))
1251 .collect::<Vec<_>>();
1252 run_compiler(&args, &mut callbacks, None, None)
1253 }).and_then(|result| result);
1254 let exit_code = match result {
1255 Ok(_) => EXIT_SUCCESS,
1256 Err(_) => EXIT_FAILURE,
1258 // The extra `\t` is necessary to align this label with the others.
1260 print_time_passes_entry(callbacks.time_passes, "\ttotal", start.elapsed());
1261 process::exit(exit_code);