src/librustc_driver/lib.rs

   1 // Copyright 2014-2015 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 //! The Rust compiler.
  12 //!
  13 //! # Note
  14 //!
  15 //! This API is completely unstable and subject to change.
  16
  17 #![crate_name = "rustc_driver"]
  18 #![unstable(feature = "rustc_private", issue = "27812")]
  19 #![crate_type = "dylib"]
  20 #![crate_type = "rlib"]
  21 #![doc(html_logo_url = "https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png",
  22       html_favicon_url = "https://doc.rust-lang.org/favicon.ico",
  23       html_root_url = "https://doc.rust-lang.org/nightly/")]
  24 #![cfg_attr(not(stage0), deny(warnings))]
  25
  26 #![feature(box_syntax)]
  27 #![feature(libc)]
  28 #![feature(quote)]
  29 #![feature(rustc_diagnostic_macros)]
  30 #![feature(rustc_private)]
  31 #![feature(set_stdio)]
  32 #![feature(staged_api)]
  33 #![feature(question_mark)]
  34 #![feature(unboxed_closures)]
  35
  36 extern crate arena;
  37 extern crate flate;
  38 extern crate getopts;
  39 extern crate graphviz;
  40 extern crate libc;
  41 extern crate rustc;
  42 extern crate rustc_back;
  43 extern crate rustc_borrowck;
  44 extern crate rustc_const_eval;
  45 extern crate rustc_errors as errors;
  46 extern crate rustc_passes;
  47 extern crate rustc_lint;
  48 extern crate rustc_plugin;
  49 extern crate rustc_privacy;
  50 extern crate rustc_incremental;
  51 extern crate rustc_metadata;
  52 extern crate rustc_mir;
  53 extern crate rustc_resolve;
  54 extern crate rustc_save_analysis;
  55 extern crate rustc_trans;
  56 extern crate rustc_typeck;
  57 extern crate serialize;
  58 extern crate rustc_llvm as llvm;
  59 #[macro_use]
  60 extern crate log;
  61 #[macro_use]
  62 extern crate syntax;
  63 extern crate syntax_ext;
  64 extern crate syntax_pos;
  65
  66 use driver::CompileController;
  67 use pretty::{PpMode, UserIdentifiedItem};
  68
  69 use rustc_resolve as resolve;
  70 use rustc_save_analysis as save;
  71 use rustc_trans::back::link;
  72 use rustc::dep_graph::DepGraph;
  73 use rustc::session::{self, config, Session, build_session, CompileResult};
  74 use rustc::session::config::{Input, PrintRequest, OutputType, ErrorOutputType};
  75 use rustc::session::config::{get_unstable_features_setting, nightly_options};
  76 use rustc::lint::Lint;
  77 use rustc::lint;
  78 use rustc_metadata::loader;
  79 use rustc_metadata::cstore::CStore;
  80 use rustc::util::common::time;
  81
  82 use std::cmp::max;
  83 use std::cmp::Ordering::Equal;
  84 use std::default::Default;
  85 use std::env;
  86 use std::io::{self, Read, Write};
  87 use std::iter::repeat;
  88 use std::path::PathBuf;
  89 use std::process;
  90 use std::rc::Rc;
  91 use std::str;
  92 use std::sync::{Arc, Mutex};
  93 use std::thread;
  94
  95 use rustc::session::early_error;
  96
  97 use syntax::{ast, json};
  98 use syntax::codemap::{CodeMap, FileLoader, RealFileLoader};
  99 use syntax::feature_gate::{GatedCfg, UnstableFeatures};
 100 use syntax::parse::{self, PResult};
 101 use syntax_pos::MultiSpan;
 102 use errors::emitter::Emitter;
 103 use errors::snippet::FormatMode;
 104
 105 #[cfg(test)]
 106 pub mod test;
 107
 108 pub mod driver;
 109 pub mod pretty;
 110 pub mod target_features;
 111
 112
 113 const BUG_REPORT_URL: &'static str = "https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.\
 114                                       md#bug-reports";
 115
 116 #[inline]
 117 fn abort_msg(err_count: usize) -> String {
 118     match err_count {
 119         0 => "aborting with no errors (maybe a bug?)".to_owned(),
 120         1 => "aborting due to previous error".to_owned(),
 121         e => format!("aborting due to {} previous errors", e),
 122     }
 123 }
 124
 125 pub fn abort_on_err<T>(result: Result<T, usize>, sess: &Session) -> T {
 126     match result {
 127         Err(err_count) => {
 128             sess.fatal(&abort_msg(err_count));
 129         }
 130         Ok(x) => x,
 131     }
 132 }
 133
 134 pub fn run(args: Vec<String>) -> isize {
 135     monitor(move || {
 136         let (result, session) = run_compiler(&args, &mut RustcDefaultCalls);
 137         if let Err(err_count) = result {
 138             if err_count > 0 {
 139                 match session {
 140                     Some(sess) => sess.fatal(&abort_msg(err_count)),
 141                     None => {
 142                         let emitter =
 143                             errors::emitter::EmitterWriter::stderr(errors::ColorConfig::Auto,
 144                                                                    None,
 145                                                                    None,
 146                                                                    FormatMode::EnvironmentSelected);
 147                         let handler = errors::Handler::with_emitter(true, false, Box::new(emitter));
 148                         handler.emit(&MultiSpan::new(),
 149                                      &abort_msg(err_count),
 150                                      errors::Level::Fatal);
 151                         exit_on_err();
 152                     }
 153                 }
 154             }
 155         }
 156     });
 157     0
 158 }
 159
 160 pub fn run_compiler<'a>(args: &[String],
 161                         callbacks: &mut CompilerCalls<'a>)
 162                         -> (CompileResult, Option<Session>) {
 163     run_compiler_with_file_loader(args, callbacks, box RealFileLoader)
 164 }
 165
 166 // Parse args and run the compiler. This is the primary entry point for rustc.
 167 // See comments on CompilerCalls below for details about the callbacks argument.
 168 // The FileLoader provides a way to load files from sources other than the file system.
 169 pub fn run_compiler_with_file_loader<'a, L>(args: &[String],
 170                                             callbacks: &mut CompilerCalls<'a>,
 171                                             loader: Box<L>)
 172                                             -> (CompileResult, Option<Session>)
 173     where L: FileLoader + 'static {
 174     macro_rules! do_or_return {($expr: expr, $sess: expr) => {
 175         match $expr {
 176             Compilation::Stop => return (Ok(()), $sess),
 177             Compilation::Continue => {}
 178         }
 179     }}
 180
 181     let matches = match handle_options(args) {
 182         Some(matches) => matches,
 183         None => return (Ok(()), None),
 184     };
 185
 186     let sopts = config::build_session_options(&matches);
 187
 188     if sopts.debugging_opts.debug_llvm {
 189         unsafe { llvm::LLVMSetDebug(1); }
 190     }
 191
 192     let descriptions = diagnostics_registry();
 193
 194     do_or_return!(callbacks.early_callback(&matches,
 195                                            &sopts,
 196                                            &descriptions,
 197                                            sopts.error_format),
 198                                            None);
 199
 200     let (odir, ofile) = make_output(&matches);
 201     let (input, input_file_path) = match make_input(&matches.free) {
 202         Some((input, input_file_path)) => callbacks.some_input(input, input_file_path),
 203         None => match callbacks.no_input(&matches, &sopts, &odir, &ofile, &descriptions) {
 204             Some((input, input_file_path)) => (input, input_file_path),
 205             None => return (Ok(()), None),
 206         },
 207     };
 208
 209     let dep_graph = DepGraph::new(sopts.build_dep_graph());
 210     let cstore = Rc::new(CStore::new(&dep_graph));
 211     let codemap = Rc::new(CodeMap::with_file_loader(loader));
 212     let sess = session::build_session_with_codemap(sopts,
 213                                                    &dep_graph,
 214                                                    input_file_path,
 215                                                    descriptions,
 216                                                    cstore.clone(),
 217                                                    codemap);
 218     rustc_lint::register_builtins(&mut sess.lint_store.borrow_mut(), Some(&sess));
 219     let mut cfg = config::build_configuration(&sess);
 220     target_features::add_configuration(&mut cfg, &sess);
 221
 222     do_or_return!(callbacks.late_callback(&matches, &sess, &input, &odir, &ofile), Some(sess));
 223
 224     let plugins = sess.opts.debugging_opts.extra_plugins.clone();
 225     let control = callbacks.build_controller(&sess, &matches);
 226     (driver::compile_input(&sess, &cstore, cfg, &input, &odir, &ofile,
 227                            Some(plugins), &control),
 228      Some(sess))
 229 }
 230
 231 // Extract output directory and file from matches.
 232 fn make_output(matches: &getopts::Matches) -> (Option<PathBuf>, Option<PathBuf>) {
 233     let odir = matches.opt_str("out-dir").map(|o| PathBuf::from(&o));
 234     let ofile = matches.opt_str("o").map(|o| PathBuf::from(&o));
 235     (odir, ofile)
 236 }
 237
 238 // Extract input (string or file and optional path) from matches.
 239 fn make_input(free_matches: &[String]) -> Option<(Input, Option<PathBuf>)> {
 240     if free_matches.len() == 1 {
 241         let ifile = &free_matches[0][..];
 242         if ifile == "-" {
 243             let mut src = String::new();
 244             io::stdin().read_to_string(&mut src).unwrap();
 245             Some((Input::Str { name: driver::anon_src(), input: src },
 246                   None))
 247         } else {
 248             Some((Input::File(PathBuf::from(ifile)),
 249                   Some(PathBuf::from(ifile))))
 250         }
 251     } else {
 252         None
 253     }
 254 }
 255
 256 fn parse_pretty(sess: &Session,
 257                 matches: &getopts::Matches)
 258                 -> Option<(PpMode, Option<UserIdentifiedItem>)> {
 259     let pretty = if sess.opts.debugging_opts.unstable_options {
 260         matches.opt_default("pretty", "normal").map(|a| {
 261             // stable pretty-print variants only
 262             pretty::parse_pretty(sess, &a, false)
 263         })
 264     } else {
 265         None
 266     };
 267     if pretty.is_none() && sess.unstable_options() {
 268         matches.opt_str("unpretty").map(|a| {
 269             // extended with unstable pretty-print variants
 270             pretty::parse_pretty(sess, &a, true)
 271         })
 272     } else {
 273         pretty
 274     }
 275 }
 276
 277 // Whether to stop or continue compilation.
 278 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
 279 pub enum Compilation {
 280     Stop,
 281     Continue,
 282 }
 283
 284 impl Compilation {
 285     pub fn and_then<F: FnOnce() -> Compilation>(self, next: F) -> Compilation {
 286         match self {
 287             Compilation::Stop => Compilation::Stop,
 288             Compilation::Continue => next(),
 289         }
 290     }
 291 }
 292
 293 // A trait for customising the compilation process. Offers a number of hooks for
 294 // executing custom code or customising input.
 295 pub trait CompilerCalls<'a> {
 296     // Hook for a callback early in the process of handling arguments. This will
 297     // be called straight after options have been parsed but before anything
 298     // else (e.g., selecting input and output).
 299     fn early_callback(&mut self,
 300                       _: &getopts::Matches,
 301                       _: &config::Options,
 302                       _: &errors::registry::Registry,
 303                       _: ErrorOutputType)
 304                       -> Compilation {
 305         Compilation::Continue
 306     }
 307
 308     // Hook for a callback late in the process of handling arguments. This will
 309     // be called just before actual compilation starts (and before build_controller
 310     // is called), after all arguments etc. have been completely handled.
 311     fn late_callback(&mut self,
 312                      _: &getopts::Matches,
 313                      _: &Session,
 314                      _: &Input,
 315                      _: &Option<PathBuf>,
 316                      _: &Option<PathBuf>)
 317                      -> Compilation {
 318         Compilation::Continue
 319     }
 320
 321     // Called after we extract the input from the arguments. Gives the implementer
 322     // an opportunity to change the inputs or to add some custom input handling.
 323     // The default behaviour is to simply pass through the inputs.
 324     fn some_input(&mut self,
 325                   input: Input,
 326                   input_path: Option<PathBuf>)
 327                   -> (Input, Option<PathBuf>) {
 328         (input, input_path)
 329     }
 330
 331     // Called after we extract the input from the arguments if there is no valid
 332     // input. Gives the implementer an opportunity to supply alternate input (by
 333     // returning a Some value) or to add custom behaviour for this error such as
 334     // emitting error messages. Returning None will cause compilation to stop
 335     // at this point.
 336     fn no_input(&mut self,
 337                 _: &getopts::Matches,
 338                 _: &config::Options,
 339                 _: &Option<PathBuf>,
 340                 _: &Option<PathBuf>,
 341                 _: &errors::registry::Registry)
 342                 -> Option<(Input, Option<PathBuf>)> {
 343         None
 344     }
 345
 346     // Create a CompilController struct for controlling the behaviour of
 347     // compilation.
 348     fn build_controller(&mut self, &Session, &getopts::Matches) -> CompileController<'a>;
 349 }
 350
 351 // CompilerCalls instance for a regular rustc build.
 352 #[derive(Copy, Clone)]
 353 pub struct RustcDefaultCalls;
 354
 355 fn handle_explain(code: &str,
 356                   descriptions: &errors::registry::Registry,
 357                   output: ErrorOutputType) {
 358     let normalised = if code.starts_with("E") {
 359         code.to_string()
 360     } else {
 361         format!("E{0:0>4}", code)
 362     };
 363     match descriptions.find_description(&normalised) {
 364         Some(ref description) => {
 365             // Slice off the leading newline and print.
 366             print!("{}", &(&description[1..]).split("\n").map(|x| {
 367                 format!("{}\n", if x.starts_with("```") {
 368                     "```"
 369                 } else {
 370                     x
 371                 })
 372             }).collect::<String>());
 373         }
 374         None => {
 375             early_error(output, &format!("no extended information for {}", code));
 376         }
 377     }
 378 }
 379
 380 fn check_cfg(sopts: &config::Options,
 381              output: ErrorOutputType) {
 382     let emitter: Box<Emitter> = match output {
 383         config::ErrorOutputType::HumanReadable(color_config) => {
 384             Box::new(errors::emitter::EmitterWriter::stderr(color_config,
 385                                                             None,
 386                                                             None,
 387                                                             FormatMode::EnvironmentSelected))
 388         }
 389         config::ErrorOutputType::Json => Box::new(json::JsonEmitter::basic()),
 390     };
 391     let handler = errors::Handler::with_emitter(true, false, emitter);
 392
 393     let mut saw_invalid_predicate = false;
 394     for item in sopts.cfg.iter() {
 395         match item.node {
 396             ast::MetaItemKind::List(ref pred, _) => {
 397                 saw_invalid_predicate = true;
 398                 handler.emit(&MultiSpan::new(),
 399                              &format!("invalid predicate in --cfg command line argument: `{}`",
 400                                       pred),
 401                                 errors::Level::Fatal);
 402             }
 403             _ => {},
 404         }
 405     }
 406
 407     if saw_invalid_predicate {
 408         panic!(errors::FatalError);
 409     }
 410 }
 411
 412 impl<'a> CompilerCalls<'a> for RustcDefaultCalls {
 413     fn early_callback(&mut self,
 414                       matches: &getopts::Matches,
 415                       sopts: &config::Options,
 416                       descriptions: &errors::registry::Registry,
 417                       output: ErrorOutputType)
 418                       -> Compilation {
 419         if let Some(ref code) = matches.opt_str("explain") {
 420             handle_explain(code, descriptions, output);
 421             return Compilation::Stop;
 422         }
 423
 424         check_cfg(sopts, output);
 425         Compilation::Continue
 426     }
 427
 428     fn no_input(&mut self,
 429                 matches: &getopts::Matches,
 430                 sopts: &config::Options,
 431                 odir: &Option<PathBuf>,
 432                 ofile: &Option<PathBuf>,
 433                 descriptions: &errors::registry::Registry)
 434                 -> Option<(Input, Option<PathBuf>)> {
 435         match matches.free.len() {
 436             0 => {
 437                 if sopts.describe_lints {
 438                     let mut ls = lint::LintStore::new();
 439                     rustc_lint::register_builtins(&mut ls, None);
 440                     describe_lints(&ls, false);
 441                     return None;
 442                 }
 443                 let dep_graph = DepGraph::new(sopts.build_dep_graph());
 444                 let cstore = Rc::new(CStore::new(&dep_graph));
 445                 let sess = build_session(sopts.clone(),
 446                     &dep_graph,
 447                     None,
 448                     descriptions.clone(),
 449                     cstore.clone());
 450                 rustc_lint::register_builtins(&mut sess.lint_store.borrow_mut(), Some(&sess));
 451                 let should_stop = RustcDefaultCalls::print_crate_info(&sess, None, odir, ofile);
 452                 if should_stop == Compilation::Stop {
 453                     return None;
 454                 }
 455                 early_error(sopts.error_format, "no input filename given");
 456             }
 457             1 => panic!("make_input should have provided valid inputs"),
 458             _ => early_error(sopts.error_format, "multiple input filenames provided"),
 459         }
 460
 461         None
 462     }
 463
 464     fn late_callback(&mut self,
 465                      matches: &getopts::Matches,
 466                      sess: &Session,
 467                      input: &Input,
 468                      odir: &Option<PathBuf>,
 469                      ofile: &Option<PathBuf>)
 470                      -> Compilation {
 471         RustcDefaultCalls::print_crate_info(sess, Some(input), odir, ofile)
 472             .and_then(|| RustcDefaultCalls::list_metadata(sess, matches, input))
 473     }
 474
 475     fn build_controller(&mut self,
 476                         sess: &Session,
 477                         matches: &getopts::Matches)
 478                         -> CompileController<'a> {
 479         let mut control = CompileController::basic();
 480
 481         if let Some((ppm, opt_uii)) = parse_pretty(sess, matches) {
 482             if ppm.needs_ast_map(&opt_uii) {
 483                 control.after_hir_lowering.stop = Compilation::Stop;
 484
 485                 control.after_parse.callback = box move |state| {
 486                     state.krate = Some(pretty::fold_crate(state.krate.take().unwrap(), ppm));
 487                 };
 488                 control.after_hir_lowering.callback = box move |state| {
 489                     pretty::print_after_hir_lowering(state.session,
 490                                                      state.ast_map.unwrap(),
 491                                                      state.analysis.unwrap(),
 492                                                      state.resolutions.unwrap(),
 493                                                      state.input,
 494                                                      &state.expanded_crate.take().unwrap(),
 495                                                      state.crate_name.unwrap(),
 496                                                      ppm,
 497                                                      state.arenas.unwrap(),
 498                                                      opt_uii.clone(),
 499                                                      state.out_file);
 500                 };
 501             } else {
 502                 control.after_parse.stop = Compilation::Stop;
 503
 504                 control.after_parse.callback = box move |state| {
 505                     let krate = pretty::fold_crate(state.krate.take().unwrap(), ppm);
 506                     pretty::print_after_parsing(state.session,
 507                                                 state.input,
 508                                                 &krate,
 509                                                 ppm,
 510                                                 state.out_file);
 511                 };
 512             }
 513
 514             return control;
 515         }
 516
 517         if sess.opts.parse_only || sess.opts.debugging_opts.show_span.is_some() ||
 518            sess.opts.debugging_opts.ast_json_noexpand {
 519             control.after_parse.stop = Compilation::Stop;
 520         }
 521
 522         if sess.opts.no_analysis || sess.opts.debugging_opts.ast_json {
 523             control.after_hir_lowering.stop = Compilation::Stop;
 524         }
 525
 526         if !sess.opts.output_types.keys().any(|&i| i == OutputType::Exe) {
 527             control.after_llvm.stop = Compilation::Stop;
 528         }
 529
 530         if save_analysis(sess) {
 531             control.after_analysis.callback = box |state| {
 532                 time(state.session.time_passes(), "save analysis", || {
 533                     save::process_crate(state.tcx.unwrap(),
 534                                         state.expanded_crate.unwrap(),
 535                                         state.analysis.unwrap(),
 536                                         state.crate_name.unwrap(),
 537                                         state.out_dir,
 538                                         save_analysis_format(state.session))
 539                 });
 540             };
 541             control.after_analysis.run_callback_on_error = true;
 542             control.make_glob_map = resolve::MakeGlobMap::Yes;
 543         }
 544
 545         control
 546     }
 547 }
 548
 549 fn save_analysis(sess: &Session) -> bool {
 550     sess.opts.debugging_opts.save_analysis ||
 551     sess.opts.debugging_opts.save_analysis_csv
 552 }
 553
 554 fn save_analysis_format(sess: &Session) -> save::Format {
 555     if sess.opts.debugging_opts.save_analysis {
 556         save::Format::Json
 557     } else if sess.opts.debugging_opts.save_analysis_csv {
 558         save::Format::Csv
 559     } else {
 560         unreachable!();
 561     }
 562 }
 563
 564 impl RustcDefaultCalls {
 565     pub fn list_metadata(sess: &Session, matches: &getopts::Matches, input: &Input) -> Compilation {
 566         let r = matches.opt_strs("Z");
 567         if r.contains(&("ls".to_string())) {
 568             match input {
 569                 &Input::File(ref ifile) => {
 570                     let path = &(*ifile);
 571                     let mut v = Vec::new();
 572                     loader::list_file_metadata(&sess.target.target, path, &mut v)
 573                         .unwrap();
 574                     println!("{}", String::from_utf8(v).unwrap());
 575                 }
 576                 &Input::Str { .. } => {
 577                     early_error(ErrorOutputType::default(), "cannot list metadata for stdin");
 578                 }
 579             }
 580             return Compilation::Stop;
 581         }
 582
 583         return Compilation::Continue;
 584     }
 585
 586
 587     fn print_crate_info(sess: &Session,
 588                         input: Option<&Input>,
 589                         odir: &Option<PathBuf>,
 590                         ofile: &Option<PathBuf>)
 591                         -> Compilation {
 592         if sess.opts.prints.is_empty() {
 593             return Compilation::Continue;
 594         }
 595
 596         let attrs = match input {
 597             None => None,
 598             Some(input) => {
 599                 let result = parse_crate_attrs(sess, input);
 600                 match result {
 601                     Ok(attrs) => Some(attrs),
 602                     Err(mut parse_error) => {
 603                         parse_error.emit();
 604                         return Compilation::Stop;
 605                     }
 606                 }
 607             }
 608         };
 609         for req in &sess.opts.prints {
 610             match *req {
 611                 PrintRequest::TargetList => {
 612                     let mut targets = rustc_back::target::TARGETS.to_vec();
 613                     targets.sort();
 614                     println!("{}", targets.join("\n"));
 615                 },
 616                 PrintRequest::Sysroot => println!("{}", sess.sysroot().display()),
 617                 PrintRequest::FileNames |
 618                 PrintRequest::CrateName => {
 619                     let input = match input {
 620                         Some(input) => input,
 621                         None => early_error(ErrorOutputType::default(), "no input file provided"),
 622                     };
 623                     let attrs = attrs.as_ref().unwrap();
 624                     let t_outputs = driver::build_output_filenames(input, odir, ofile, attrs, sess);
 625                     let id = link::find_crate_name(Some(sess), attrs, input);
 626                     if *req == PrintRequest::CrateName {
 627                         println!("{}", id);
 628                         continue;
 629                     }
 630                     let crate_types = driver::collect_crate_types(sess, attrs);
 631                     for &style in &crate_types {
 632                         let fname = link::filename_for_input(sess, style, &id, &t_outputs);
 633                         println!("{}",
 634                                  fname.file_name()
 635                                       .unwrap()
 636                                       .to_string_lossy());
 637                     }
 638                 }
 639                 PrintRequest::Cfg => {
 640                     let mut cfg = config::build_configuration(&sess);
 641                     target_features::add_configuration(&mut cfg, &sess);
 642
 643                     let allow_unstable_cfg = match get_unstable_features_setting() {
 644                         UnstableFeatures::Disallow => false,
 645                         _ => true,
 646                     };
 647
 648                     for cfg in cfg {
 649                         if !allow_unstable_cfg && GatedCfg::gate(&*cfg).is_some() {
 650                             continue;
 651                         }
 652                         match cfg.node {
 653                             ast::MetaItemKind::Word(ref word) => println!("{}", word),
 654                             ast::MetaItemKind::NameValue(ref name, ref value) => {
 655                                 println!("{}=\"{}\"", name, match value.node {
 656                                     ast::LitKind::Str(ref s, _) => s,
 657                                     _ => continue,
 658                                 });
 659                             }
 660                             // Right now there are not and should not be any
 661                             // MetaItemKind::List items in the configuration returned by
 662                             // `build_configuration`.
 663                             ast::MetaItemKind::List(..) => {
 664                                 panic!("MetaItemKind::List encountered in default cfg")
 665                             }
 666                         }
 667                     }
 668                 }
 669             }
 670         }
 671         return Compilation::Stop;
 672     }
 673 }
 674
 675 /// Returns a version string such as "0.12.0-dev".
 676 pub fn release_str() -> Option<&'static str> {
 677     option_env!("CFG_RELEASE")
 678 }
 679
 680 /// Returns the full SHA1 hash of HEAD of the Git repo from which rustc was built.
 681 pub fn commit_hash_str() -> Option<&'static str> {
 682     option_env!("CFG_VER_HASH")
 683 }
 684
 685 /// Returns the "commit date" of HEAD of the Git repo from which rustc was built as a static string.
 686 pub fn commit_date_str() -> Option<&'static str> {
 687     option_env!("CFG_VER_DATE")
 688 }
 689
 690 /// Prints version information
 691 pub fn version(binary: &str, matches: &getopts::Matches) {
 692     let verbose = matches.opt_present("verbose");
 693
 694     println!("{} {}",
 695              binary,
 696              option_env!("CFG_VERSION").unwrap_or("unknown version"));
 697     if verbose {
 698         fn unw(x: Option<&str>) -> &str {
 699             x.unwrap_or("unknown")
 700         }
 701         println!("binary: {}", binary);
 702         println!("commit-hash: {}", unw(commit_hash_str()));
 703         println!("commit-date: {}", unw(commit_date_str()));
 704         println!("host: {}", config::host_triple());
 705         println!("release: {}", unw(release_str()));
 706     }
 707 }
 708
 709 fn usage(verbose: bool, include_unstable_options: bool) {
 710     let groups = if verbose {
 711         config::rustc_optgroups()
 712     } else {
 713         config::rustc_short_optgroups()
 714     };
 715     let groups: Vec<_> = groups.into_iter()
 716                                .filter(|x| include_unstable_options || x.is_stable())
 717                                .map(|x| x.opt_group)
 718                                .collect();
 719     let message = format!("Usage: rustc [OPTIONS] INPUT");
 720     let extra_help = if verbose {
 721         ""
 722     } else {
 723         "\n    --help -v           Print the full set of options rustc accepts"
 724     };
 725     println!("{}\nAdditional help:
 726     -C help             Print codegen options
 727     -W help             \
 728               Print 'lint' options and default settings
 729     -Z help             Print internal \
 730               options for debugging rustc{}\n",
 731              getopts::usage(&message, &groups),
 732              extra_help);
 733 }
 734
 735 fn describe_lints(lint_store: &lint::LintStore, loaded_plugins: bool) {
 736     println!("
 737 Available lint options:
 738     -W <foo>           Warn about <foo>
 739     -A <foo>           \
 740               Allow <foo>
 741     -D <foo>           Deny <foo>
 742     -F <foo>           Forbid <foo> \
 743               (deny, and deny all overrides)
 744
 745 ");
 746
 747     fn sort_lints(lints: Vec<(&'static Lint, bool)>) -> Vec<&'static Lint> {
 748         let mut lints: Vec<_> = lints.into_iter().map(|(x, _)| x).collect();
 749         lints.sort_by(|x: &&Lint, y: &&Lint| {
 750             match x.default_level.cmp(&y.default_level) {
 751                 // The sort doesn't case-fold but it's doubtful we care.
 752                 Equal => x.name.cmp(y.name),
 753                 r => r,
 754             }
 755         });
 756         lints
 757     }
 758
 759     fn sort_lint_groups(lints: Vec<(&'static str, Vec<lint::LintId>, bool)>)
 760                         -> Vec<(&'static str, Vec<lint::LintId>)> {
 761         let mut lints: Vec<_> = lints.into_iter().map(|(x, y, _)| (x, y)).collect();
 762         lints.sort_by(|&(x, _): &(&'static str, Vec<lint::LintId>),
 763                        &(y, _): &(&'static str, Vec<lint::LintId>)| {
 764             x.cmp(y)
 765         });
 766         lints
 767     }
 768
 769     let (plugin, builtin): (Vec<_>, _) = lint_store.get_lints()
 770                                                    .iter()
 771                                                    .cloned()
 772                                                    .partition(|&(_, p)| p);
 773     let plugin = sort_lints(plugin);
 774     let builtin = sort_lints(builtin);
 775
 776     let (plugin_groups, builtin_groups): (Vec<_>, _) = lint_store.get_lint_groups()
 777                                                                  .iter()
 778                                                                  .cloned()
 779                                                                  .partition(|&(_, _, p)| p);
 780     let plugin_groups = sort_lint_groups(plugin_groups);
 781     let builtin_groups = sort_lint_groups(builtin_groups);
 782
 783     let max_name_len = plugin.iter()
 784                              .chain(&builtin)
 785                              .map(|&s| s.name.chars().count())
 786                              .max()
 787                              .unwrap_or(0);
 788     let padded = |x: &str| {
 789         let mut s = repeat(" ")
 790                         .take(max_name_len - x.chars().count())
 791                         .collect::<String>();
 792         s.push_str(x);
 793         s
 794     };
 795
 796     println!("Lint checks provided by rustc:\n");
 797     println!("    {}  {:7.7}  {}", padded("name"), "default", "meaning");
 798     println!("    {}  {:7.7}  {}", padded("----"), "-------", "-------");
 799
 800     let print_lints = |lints: Vec<&Lint>| {
 801         for lint in lints {
 802             let name = lint.name_lower().replace("_", "-");
 803             println!("    {}  {:7.7}  {}",
 804                      padded(&name[..]),
 805                      lint.default_level.as_str(),
 806                      lint.desc);
 807         }
 808         println!("\n");
 809     };
 810
 811     print_lints(builtin);
 812
 813
 814
 815     let max_name_len = max("warnings".len(),
 816                            plugin_groups.iter()
 817                                         .chain(&builtin_groups)
 818                                         .map(|&(s, _)| s.chars().count())
 819                                         .max()
 820                                         .unwrap_or(0));
 821
 822     let padded = |x: &str| {
 823         let mut s = repeat(" ")
 824                         .take(max_name_len - x.chars().count())
 825                         .collect::<String>();
 826         s.push_str(x);
 827         s
 828     };
 829
 830     println!("Lint groups provided by rustc:\n");
 831     println!("    {}  {}", padded("name"), "sub-lints");
 832     println!("    {}  {}", padded("----"), "---------");
 833     println!("    {}  {}", padded("warnings"), "all built-in lints");
 834
 835     let print_lint_groups = |lints: Vec<(&'static str, Vec<lint::LintId>)>| {
 836         for (name, to) in lints {
 837             let name = name.to_lowercase().replace("_", "-");
 838             let desc = to.into_iter()
 839                          .map(|x| x.as_str().replace("_", "-"))
 840                          .collect::<Vec<String>>()
 841                          .join(", ");
 842             println!("    {}  {}", padded(&name[..]), desc);
 843         }
 844         println!("\n");
 845     };
 846
 847     print_lint_groups(builtin_groups);
 848
 849     match (loaded_plugins, plugin.len(), plugin_groups.len()) {
 850         (false, 0, _) | (false, _, 0) => {
 851             println!("Compiler plugins can provide additional lints and lint groups. To see a \
 852                       listing of these, re-run `rustc -W help` with a crate filename.");
 853         }
 854         (false, _, _) => panic!("didn't load lint plugins but got them anyway!"),
 855         (true, 0, 0) => println!("This crate does not load any lint plugins or lint groups."),
 856         (true, l, g) => {
 857             if l > 0 {
 858                 println!("Lint checks provided by plugins loaded by this crate:\n");
 859                 print_lints(plugin);
 860             }
 861             if g > 0 {
 862                 println!("Lint groups provided by plugins loaded by this crate:\n");
 863                 print_lint_groups(plugin_groups);
 864             }
 865         }
 866     }
 867 }
 868
 869 fn describe_debug_flags() {
 870     println!("\nAvailable debug options:\n");
 871     print_flag_list("-Z", config::DB_OPTIONS);
 872 }
 873
 874 fn describe_codegen_flags() {
 875     println!("\nAvailable codegen options:\n");
 876     print_flag_list("-C", config::CG_OPTIONS);
 877 }
 878
 879 fn print_flag_list<T>(cmdline_opt: &str,
 880                       flag_list: &[(&'static str, T, Option<&'static str>, &'static str)]) {
 881     let max_len = flag_list.iter()
 882                            .map(|&(name, _, opt_type_desc, _)| {
 883                                let extra_len = match opt_type_desc {
 884                                    Some(..) => 4,
 885                                    None => 0,
 886                                };
 887                                name.chars().count() + extra_len
 888                            })
 889                            .max()
 890                            .unwrap_or(0);
 891
 892     for &(name, _, opt_type_desc, desc) in flag_list {
 893         let (width, extra) = match opt_type_desc {
 894             Some(..) => (max_len - 4, "=val"),
 895             None => (max_len, ""),
 896         };
 897         println!("    {} {:>width$}{} -- {}",
 898                  cmdline_opt,
 899                  name.replace("_", "-"),
 900                  extra,
 901                  desc,
 902                  width = width);
 903     }
 904 }
 905
 906 /// Process command line options. Emits messages as appropriate. If compilation
 907 /// should continue, returns a getopts::Matches object parsed from args,
 908 /// otherwise returns None.
 909 ///
 910 /// The compiler's handling of options is a little complication as it ties into
 911 /// our stability story, and it's even *more* complicated by historical
 912 /// accidents. The current intention of each compiler option is to have one of
 913 /// three modes:
 914 ///
 915 /// 1. An option is stable and can be used everywhere.
 916 /// 2. An option is unstable, but was historically allowed on the stable
 917 ///    channel.
 918 /// 3. An option is unstable, and can only be used on nightly.
 919 ///
 920 /// Like unstable library and language features, however, unstable options have
 921 /// always required a form of "opt in" to indicate that you're using them. This
 922 /// provides the easy ability to scan a code base to check to see if anything
 923 /// unstable is being used. Currently, this "opt in" is the `-Z` "zed" flag.
 924 ///
 925 /// All options behind `-Z` are considered unstable by default. Other top-level
 926 /// options can also be considered unstable, and they were unlocked through the
 927 /// `-Z unstable-options` flag. Note that `-Z` remains to be the root of
 928 /// instability in both cases, though.
 929 ///
 930 /// So with all that in mind, the comments below have some more detail about the
 931 /// contortions done here to get things to work out correctly.
 932 pub fn handle_options(args: &[String]) -> Option<getopts::Matches> {
 933     // Throw away the first argument, the name of the binary
 934     let args = &args[1..];
 935
 936     if args.is_empty() {
 937         // user did not write `-v` nor `-Z unstable-options`, so do not
 938         // include that extra information.
 939         usage(false, false);
 940         return None;
 941     }
 942
 943     // Parse with *all* options defined in the compiler, we don't worry about
 944     // option stability here we just want to parse as much as possible.
 945     let all_groups: Vec<getopts::OptGroup> = config::rustc_optgroups()
 946                                                  .into_iter()
 947                                                  .map(|x| x.opt_group)
 948                                                  .collect();
 949     let matches = match getopts::getopts(&args[..], &all_groups) {
 950         Ok(m) => m,
 951         Err(f) => early_error(ErrorOutputType::default(), &f.to_string()),
 952     };
 953
 954     // For all options we just parsed, we check a few aspects:
 955     //
 956     // * If the option is stable, we're all good
 957     // * If the option wasn't passed, we're all good
 958     // * If `-Z unstable-options` wasn't passed (and we're not a -Z option
 959     //   ourselves), then we require the `-Z unstable-options` flag to unlock
 960     //   this option that was passed.
 961     // * If we're a nightly compiler, then unstable options are now unlocked, so
 962     //   we're good to go.
 963     // * Otherwise, if we're a truly unstable option then we generate an error
 964     //   (unstable option being used on stable)
 965     // * If we're a historically stable-but-should-be-unstable option then we
 966     //   emit a warning that we're going to turn this into an error soon.
 967     nightly_options::check_nightly_options(&matches, &config::rustc_optgroups());
 968
 969     if matches.opt_present("h") || matches.opt_present("help") {
 970         // Only show unstable options in --help if we *really* accept unstable
 971         // options, which catches the case where we got `-Z unstable-options` on
 972         // the stable channel of Rust which was accidentally allowed
 973         // historically.
 974         usage(matches.opt_present("verbose"),
 975               nightly_options::is_unstable_enabled(&matches));
 976         return None;
 977     }
 978
 979     // Don't handle -W help here, because we might first load plugins.
 980     let r = matches.opt_strs("Z");
 981     if r.iter().any(|x| *x == "help") {
 982         describe_debug_flags();
 983         return None;
 984     }
 985
 986     let cg_flags = matches.opt_strs("C");
 987     if cg_flags.iter().any(|x| *x == "help") {
 988         describe_codegen_flags();
 989         return None;
 990     }
 991
 992     if cg_flags.contains(&"passes=list".to_string()) {
 993         unsafe {
 994             ::llvm::LLVMRustPrintPasses();
 995         }
 996         return None;
 997     }
 998
 999     if matches.opt_present("version") {
1000         version("rustc", &matches);
1001         return None;
1002     }
1003
1004     Some(matches)
1005 }
1006
1007 fn parse_crate_attrs<'a>(sess: &'a Session, input: &Input) -> PResult<'a, Vec<ast::Attribute>> {
1008     match *input {
1009         Input::File(ref ifile) => {
1010             parse::parse_crate_attrs_from_file(ifile, Vec::new(), &sess.parse_sess)
1011         }
1012         Input::Str { ref name, ref input } => {
1013             parse::parse_crate_attrs_from_source_str(name.clone(),
1014                                                      input.clone(),
1015                                                      Vec::new(),
1016                                                      &sess.parse_sess)
1017         }
1018     }
1019 }
1020
1021 /// Run a procedure which will detect panics in the compiler and print nicer
1022 /// error messages rather than just failing the test.
1023 ///
1024 /// The diagnostic emitter yielded to the procedure should be used for reporting
1025 /// errors of the compiler.
1026 pub fn monitor<F: FnOnce() + Send + 'static>(f: F) {
1027     const STACK_SIZE: usize = 8 * 1024 * 1024; // 8MB
1028
1029     struct Sink(Arc<Mutex<Vec<u8>>>);
1030     impl Write for Sink {
1031         fn write(&mut self, data: &[u8]) -> io::Result<usize> {
1032             Write::write(&mut *self.0.lock().unwrap(), data)
1033         }
1034         fn flush(&mut self) -> io::Result<()> {
1035             Ok(())
1036         }
1037     }
1038
1039     let data = Arc::new(Mutex::new(Vec::new()));
1040     let err = Sink(data.clone());
1041
1042     let mut cfg = thread::Builder::new().name("rustc".to_string());
1043
1044     // FIXME: Hacks on hacks. If the env is trying to override the stack size
1045     // then *don't* set it explicitly.
1046     if env::var_os("RUST_MIN_STACK").is_none() {
1047         cfg = cfg.stack_size(STACK_SIZE);
1048     }
1049
1050     let thread = cfg.spawn(move || {
1051          io::set_panic(box err);
1052          f()
1053      });
1054
1055      if let Err(value) = thread.unwrap().join() {
1056         // Thread panicked without emitting a fatal diagnostic
1057         if !value.is::<errors::FatalError>() {
1058             let emitter =
1059                 Box::new(errors::emitter::EmitterWriter::stderr(errors::ColorConfig::Auto,
1060                                                        None,
1061                                                        None,
1062                                                        FormatMode::EnvironmentSelected));
1063             let handler = errors::Handler::with_emitter(true, false, emitter);
1064
1065             // a .span_bug or .bug call has already printed what
1066             // it wants to print.
1067             if !value.is::<errors::ExplicitBug>() {
1068                 handler.emit(&MultiSpan::new(),
1069                              "unexpected panic",
1070                              errors::Level::Bug);
1071             }
1072
1073             let xs = ["the compiler unexpectedly panicked. this is a bug.".to_string(),
1074                       format!("we would appreciate a bug report: {}", BUG_REPORT_URL)];
1075             for note in &xs {
1076                 handler.emit(&MultiSpan::new(),
1077                              &note[..],
1078                              errors::Level::Note);
1079             }
1080             if match env::var_os("RUST_BACKTRACE") {
1081                 Some(val) => &val != "0",
1082                 None => false,
1083             } {
1084                 handler.emit(&MultiSpan::new(),
1085                              "run with `RUST_BACKTRACE=1` for a backtrace",
1086                              errors::Level::Note);
1087             }
1088
1089             println!("{}", str::from_utf8(&data.lock().unwrap()).unwrap());
1090         }
1091
1092         exit_on_err();
1093     }
1094 }
1095
1096 fn exit_on_err() -> ! {
1097     // Panic so the process returns a failure code, but don't pollute the
1098     // output with some unnecessary panic messages, we've already
1099     // printed everything that we needed to.
1100     io::set_panic(box io::sink());
1101     panic!();
1102 }
1103
1104 pub fn diagnostics_registry() -> errors::registry::Registry {
1105     use errors::registry::Registry;
1106
1107     let mut all_errors = Vec::new();
1108     all_errors.extend_from_slice(&rustc::DIAGNOSTICS);
1109     all_errors.extend_from_slice(&rustc_typeck::DIAGNOSTICS);
1110     all_errors.extend_from_slice(&rustc_borrowck::DIAGNOSTICS);
1111     all_errors.extend_from_slice(&rustc_resolve::DIAGNOSTICS);
1112     all_errors.extend_from_slice(&rustc_privacy::DIAGNOSTICS);
1113     all_errors.extend_from_slice(&rustc_trans::DIAGNOSTICS);
1114     all_errors.extend_from_slice(&rustc_const_eval::DIAGNOSTICS);
1115
1116     Registry::new(&all_errors)
1117 }
1118
1119 pub fn main() {
1120     let result = run(env::args().collect());
1121     process::exit(result as i32);
1122 }