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 #![deny(warnings)]
  25
  26 #![feature(box_syntax)]
  27 #![feature(loop_break_value)]
  28 #![feature(libc)]
  29 #![feature(quote)]
  30 #![feature(rustc_diagnostic_macros)]
  31 #![feature(rustc_private)]
  32 #![feature(set_stdio)]
  33 #![feature(staged_api)]
  34
  35 extern crate arena;
  36 extern crate getopts;
  37 extern crate graphviz;
  38 extern crate env_logger;
  39 extern crate libc;
  40 extern crate rustc;
  41 extern crate rustc_back;
  42 extern crate rustc_borrowck;
  43 extern crate rustc_const_eval;
  44 extern crate rustc_data_structures;
  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 extern crate syntax;
  62 extern crate syntax_ext;
  63 extern crate syntax_pos;
  64
  65 use driver::CompileController;
  66 use pretty::{PpMode, UserIdentifiedItem};
  67
  68 use rustc_resolve as resolve;
  69 use rustc_save_analysis as save;
  70 use rustc_save_analysis::DumpHandler;
  71 use rustc_trans::back::link;
  72 use rustc_trans::back::write::{create_target_machine, RELOC_MODEL_ARGS, CODE_GEN_MODEL_ARGS};
  73 use rustc::dep_graph::DepGraph;
  74 use rustc::session::{self, config, Session, build_session, CompileResult};
  75 use rustc::session::config::{Input, PrintRequest, OutputType, ErrorOutputType};
  76 use rustc::session::config::nightly_options;
  77 use rustc::session::{early_error, early_warn};
  78 use rustc::lint::Lint;
  79 use rustc::lint;
  80 use rustc_metadata::locator;
  81 use rustc_metadata::cstore::CStore;
  82 use rustc::util::common::time;
  83
  84 use serialize::json::ToJson;
  85
  86 use std::any::Any;
  87 use std::cmp::max;
  88 use std::cmp::Ordering::Equal;
  89 use std::default::Default;
  90 use std::env;
  91 use std::io::{self, Read, Write};
  92 use std::iter::repeat;
  93 use std::path::PathBuf;
  94 use std::process;
  95 use std::rc::Rc;
  96 use std::str;
  97 use std::sync::{Arc, Mutex};
  98 use std::thread;
  99
 100 use syntax::ast;
 101 use syntax::codemap::{CodeMap, FileLoader, RealFileLoader};
 102 use syntax::feature_gate::{GatedCfg, UnstableFeatures};
 103 use syntax::parse::{self, PResult};
 104 use syntax_pos::{DUMMY_SP, MultiSpan};
 105
 106 #[cfg(test)]
 107 pub mod test;
 108
 109 pub mod driver;
 110 pub mod pretty;
 111 pub mod target_features;
 112 mod derive_registrar;
 113
 114 const BUG_REPORT_URL: &'static str = "https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.\
 115                                       md#bug-reports";
 116
 117 #[inline]
 118 fn abort_msg(err_count: usize) -> String {
 119     match err_count {
 120         0 => "aborting with no errors (maybe a bug?)".to_owned(),
 121         1 => "aborting due to previous error".to_owned(),
 122         e => format!("aborting due to {} previous errors", e),
 123     }
 124 }
 125
 126 pub fn abort_on_err<T>(result: Result<T, usize>, sess: &Session) -> T {
 127     match result {
 128         Err(err_count) => {
 129             sess.fatal(&abort_msg(err_count));
 130         }
 131         Ok(x) => x,
 132     }
 133 }
 134
 135 pub fn run<F>(run_compiler: F) -> isize
 136     where F: FnOnce() -> (CompileResult, Option<Session>) + Send + 'static
 137 {
 138     monitor(move || {
 139         let (result, session) = run_compiler();
 140         if let Err(err_count) = result {
 141             if err_count > 0 {
 142                 match session {
 143                     Some(sess) => sess.fatal(&abort_msg(err_count)),
 144                     None => {
 145                         let emitter =
 146                             errors::emitter::EmitterWriter::stderr(errors::ColorConfig::Auto, None);
 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 // Parse args and run the compiler. This is the primary entry point for rustc.
 161 // See comments on CompilerCalls below for details about the callbacks argument.
 162 // The FileLoader provides a way to load files from sources other than the file system.
 163 pub fn run_compiler<'a>(args: &[String],
 164                         callbacks: &mut CompilerCalls<'a>,
 165                         file_loader: Option<Box<FileLoader + 'static>>,
 166                         emitter_dest: Option<Box<Write + Send>>)
 167                         -> (CompileResult, Option<Session>)
 168 {
 169     macro_rules! do_or_return {($expr: expr, $sess: expr) => {
 170         match $expr {
 171             Compilation::Stop => return (Ok(()), $sess),
 172             Compilation::Continue => {}
 173         }
 174     }}
 175
 176     let matches = match handle_options(args) {
 177         Some(matches) => matches,
 178         None => return (Ok(()), None),
 179     };
 180
 181     let (sopts, cfg) = config::build_session_options_and_crate_config(&matches);
 182
 183     if sopts.debugging_opts.debug_llvm {
 184         unsafe { llvm::LLVMRustSetDebug(1); }
 185     }
 186
 187     let descriptions = diagnostics_registry();
 188
 189     do_or_return!(callbacks.early_callback(&matches,
 190                                            &sopts,
 191                                            &cfg,
 192                                            &descriptions,
 193                                            sopts.error_format),
 194                                            None);
 195
 196     let (odir, ofile) = make_output(&matches);
 197     let (input, input_file_path) = match make_input(&matches.free) {
 198         Some((input, input_file_path)) => callbacks.some_input(input, input_file_path),
 199         None => match callbacks.no_input(&matches, &sopts, &cfg, &odir, &ofile, &descriptions) {
 200             Some((input, input_file_path)) => (input, input_file_path),
 201             None => return (Ok(()), None),
 202         },
 203     };
 204
 205     let dep_graph = DepGraph::new(sopts.build_dep_graph());
 206     let cstore = Rc::new(CStore::new(&dep_graph));
 207
 208     let loader = file_loader.unwrap_or(box RealFileLoader);
 209     let codemap = Rc::new(CodeMap::with_file_loader(loader));
 210     let mut sess = session::build_session_with_codemap(
 211         sopts, &dep_graph, input_file_path, descriptions, cstore.clone(), codemap, emitter_dest,
 212     );
 213     rustc_lint::register_builtins(&mut sess.lint_store.borrow_mut(), Some(&sess));
 214
 215     let mut cfg = config::build_configuration(&sess, cfg);
 216     target_features::add_configuration(&mut cfg, &sess);
 217     sess.parse_sess.config = cfg;
 218
 219     do_or_return!(callbacks.late_callback(&matches, &sess, &input, &odir, &ofile), Some(sess));
 220
 221     let plugins = sess.opts.debugging_opts.extra_plugins.clone();
 222     let control = callbacks.build_controller(&sess, &matches);
 223     (driver::compile_input(&sess, &cstore, &input, &odir, &ofile, Some(plugins), &control),
 224      Some(sess))
 225 }
 226
 227 // Extract output directory and file from matches.
 228 fn make_output(matches: &getopts::Matches) -> (Option<PathBuf>, Option<PathBuf>) {
 229     let odir = matches.opt_str("out-dir").map(|o| PathBuf::from(&o));
 230     let ofile = matches.opt_str("o").map(|o| PathBuf::from(&o));
 231     (odir, ofile)
 232 }
 233
 234 // Extract input (string or file and optional path) from matches.
 235 fn make_input(free_matches: &[String]) -> Option<(Input, Option<PathBuf>)> {
 236     if free_matches.len() == 1 {
 237         let ifile = &free_matches[0];
 238         if ifile == "-" {
 239             let mut src = String::new();
 240             io::stdin().read_to_string(&mut src).unwrap();
 241             Some((Input::Str { name: driver::anon_src(), input: src },
 242                   None))
 243         } else {
 244             Some((Input::File(PathBuf::from(ifile)),
 245                   Some(PathBuf::from(ifile))))
 246         }
 247     } else {
 248         None
 249     }
 250 }
 251
 252 fn parse_pretty(sess: &Session,
 253                 matches: &getopts::Matches)
 254                 -> Option<(PpMode, Option<UserIdentifiedItem>)> {
 255     let pretty = if sess.opts.debugging_opts.unstable_options {
 256         matches.opt_default("pretty", "normal").map(|a| {
 257             // stable pretty-print variants only
 258             pretty::parse_pretty(sess, &a, false)
 259         })
 260     } else {
 261         None
 262     };
 263     if pretty.is_none() && sess.unstable_options() {
 264         matches.opt_str("unpretty").map(|a| {
 265             // extended with unstable pretty-print variants
 266             pretty::parse_pretty(sess, &a, true)
 267         })
 268     } else {
 269         pretty
 270     }
 271 }
 272
 273 // Whether to stop or continue compilation.
 274 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
 275 pub enum Compilation {
 276     Stop,
 277     Continue,
 278 }
 279
 280 impl Compilation {
 281     pub fn and_then<F: FnOnce() -> Compilation>(self, next: F) -> Compilation {
 282         match self {
 283             Compilation::Stop => Compilation::Stop,
 284             Compilation::Continue => next(),
 285         }
 286     }
 287 }
 288
 289 // A trait for customising the compilation process. Offers a number of hooks for
 290 // executing custom code or customising input.
 291 pub trait CompilerCalls<'a> {
 292     // Hook for a callback early in the process of handling arguments. This will
 293     // be called straight after options have been parsed but before anything
 294     // else (e.g., selecting input and output).
 295     fn early_callback(&mut self,
 296                       _: &getopts::Matches,
 297                       _: &config::Options,
 298                       _: &ast::CrateConfig,
 299                       _: &errors::registry::Registry,
 300                       _: ErrorOutputType)
 301                       -> Compilation {
 302         Compilation::Continue
 303     }
 304
 305     // Hook for a callback late in the process of handling arguments. This will
 306     // be called just before actual compilation starts (and before build_controller
 307     // is called), after all arguments etc. have been completely handled.
 308     fn late_callback(&mut self,
 309                      _: &getopts::Matches,
 310                      _: &Session,
 311                      _: &Input,
 312                      _: &Option<PathBuf>,
 313                      _: &Option<PathBuf>)
 314                      -> Compilation {
 315         Compilation::Continue
 316     }
 317
 318     // Called after we extract the input from the arguments. Gives the implementer
 319     // an opportunity to change the inputs or to add some custom input handling.
 320     // The default behaviour is to simply pass through the inputs.
 321     fn some_input(&mut self,
 322                   input: Input,
 323                   input_path: Option<PathBuf>)
 324                   -> (Input, Option<PathBuf>) {
 325         (input, input_path)
 326     }
 327
 328     // Called after we extract the input from the arguments if there is no valid
 329     // input. Gives the implementer an opportunity to supply alternate input (by
 330     // returning a Some value) or to add custom behaviour for this error such as
 331     // emitting error messages. Returning None will cause compilation to stop
 332     // at this point.
 333     fn no_input(&mut self,
 334                 _: &getopts::Matches,
 335                 _: &config::Options,
 336                 _: &ast::CrateConfig,
 337                 _: &Option<PathBuf>,
 338                 _: &Option<PathBuf>,
 339                 _: &errors::registry::Registry)
 340                 -> Option<(Input, Option<PathBuf>)> {
 341         None
 342     }
 343
 344     // Create a CompilController struct for controlling the behaviour of
 345     // compilation.
 346     fn build_controller(&mut self, &Session, &getopts::Matches) -> CompileController<'a>;
 347 }
 348
 349 // CompilerCalls instance for a regular rustc build.
 350 #[derive(Copy, Clone)]
 351 pub struct RustcDefaultCalls;
 352
 353 fn handle_explain(code: &str,
 354                   descriptions: &errors::registry::Registry,
 355                   output: ErrorOutputType) {
 356     let normalised = if code.starts_with("E") {
 357         code.to_string()
 358     } else {
 359         format!("E{0:0>4}", code)
 360     };
 361     match descriptions.find_description(&normalised) {
 362         Some(ref description) => {
 363             // Slice off the leading newline and print.
 364             print!("{}", &(&description[1..]).split("\n").map(|x| {
 365                 format!("{}\n", if x.starts_with("```") {
 366                     "```"
 367                 } else {
 368                     x
 369                 })
 370             }).collect::<String>());
 371         }
 372         None => {
 373             early_error(output, &format!("no extended information for {}", code));
 374         }
 375     }
 376 }
 377
 378 impl<'a> CompilerCalls<'a> for RustcDefaultCalls {
 379     fn early_callback(&mut self,
 380                       matches: &getopts::Matches,
 381                       _: &config::Options,
 382                       _: &ast::CrateConfig,
 383                       descriptions: &errors::registry::Registry,
 384                       output: ErrorOutputType)
 385                       -> Compilation {
 386         if let Some(ref code) = matches.opt_str("explain") {
 387             handle_explain(code, descriptions, output);
 388             return Compilation::Stop;
 389         }
 390
 391         Compilation::Continue
 392     }
 393
 394     fn no_input(&mut self,
 395                 matches: &getopts::Matches,
 396                 sopts: &config::Options,
 397                 cfg: &ast::CrateConfig,
 398                 odir: &Option<PathBuf>,
 399                 ofile: &Option<PathBuf>,
 400                 descriptions: &errors::registry::Registry)
 401                 -> Option<(Input, Option<PathBuf>)> {
 402         match matches.free.len() {
 403             0 => {
 404                 if sopts.describe_lints {
 405                     let mut ls = lint::LintStore::new();
 406                     rustc_lint::register_builtins(&mut ls, None);
 407                     describe_lints(&ls, false);
 408                     return None;
 409                 }
 410                 let dep_graph = DepGraph::new(sopts.build_dep_graph());
 411                 let cstore = Rc::new(CStore::new(&dep_graph));
 412                 let mut sess = build_session(sopts.clone(),
 413                     &dep_graph,
 414                     None,
 415                     descriptions.clone(),
 416                     cstore.clone());
 417                 rustc_lint::register_builtins(&mut sess.lint_store.borrow_mut(), Some(&sess));
 418                 let mut cfg = config::build_configuration(&sess, cfg.clone());
 419                 target_features::add_configuration(&mut cfg, &sess);
 420                 sess.parse_sess.config = cfg;
 421                 let should_stop =
 422                     RustcDefaultCalls::print_crate_info(&sess, None, odir, ofile);
 423
 424                 if should_stop == Compilation::Stop {
 425                     return None;
 426                 }
 427                 early_error(sopts.error_format, "no input filename given");
 428             }
 429             1 => panic!("make_input should have provided valid inputs"),
 430             _ => early_error(sopts.error_format, "multiple input filenames provided"),
 431         }
 432     }
 433
 434     fn late_callback(&mut self,
 435                      matches: &getopts::Matches,
 436                      sess: &Session,
 437                      input: &Input,
 438                      odir: &Option<PathBuf>,
 439                      ofile: &Option<PathBuf>)
 440                      -> Compilation {
 441         RustcDefaultCalls::print_crate_info(sess, Some(input), odir, ofile)
 442             .and_then(|| RustcDefaultCalls::list_metadata(sess, matches, input))
 443     }
 444
 445     fn build_controller(&mut self,
 446                         sess: &Session,
 447                         matches: &getopts::Matches)
 448                         -> CompileController<'a> {
 449         let mut control = CompileController::basic();
 450
 451         if let Some((ppm, opt_uii)) = parse_pretty(sess, matches) {
 452             if ppm.needs_ast_map(&opt_uii) {
 453                 control.after_hir_lowering.stop = Compilation::Stop;
 454
 455                 control.after_parse.callback = box move |state| {
 456                     state.krate = Some(pretty::fold_crate(state.krate.take().unwrap(), ppm));
 457                 };
 458                 control.after_hir_lowering.callback = box move |state| {
 459                     pretty::print_after_hir_lowering(state.session,
 460                                                      state.hir_map.unwrap(),
 461                                                      state.analysis.unwrap(),
 462                                                      state.resolutions.unwrap(),
 463                                                      state.input,
 464                                                      &state.expanded_crate.take().unwrap(),
 465                                                      state.crate_name.unwrap(),
 466                                                      ppm,
 467                                                      state.arena.unwrap(),
 468                                                      state.arenas.unwrap(),
 469                                                      opt_uii.clone(),
 470                                                      state.out_file);
 471                 };
 472             } else {
 473                 control.after_parse.stop = Compilation::Stop;
 474
 475                 control.after_parse.callback = box move |state| {
 476                     let krate = pretty::fold_crate(state.krate.take().unwrap(), ppm);
 477                     pretty::print_after_parsing(state.session,
 478                                                 state.input,
 479                                                 &krate,
 480                                                 ppm,
 481                                                 state.out_file);
 482                 };
 483             }
 484
 485             return control;
 486         }
 487
 488         if sess.opts.debugging_opts.parse_only ||
 489            sess.opts.debugging_opts.show_span.is_some() ||
 490            sess.opts.debugging_opts.ast_json_noexpand {
 491             control.after_parse.stop = Compilation::Stop;
 492         }
 493
 494         if sess.opts.debugging_opts.no_analysis ||
 495            sess.opts.debugging_opts.ast_json {
 496             control.after_hir_lowering.stop = Compilation::Stop;
 497         }
 498
 499         if !sess.opts.output_types.keys().any(|&i| i == OutputType::Exe ||
 500                                                    i == OutputType::Metadata) {
 501             control.after_llvm.stop = Compilation::Stop;
 502         }
 503
 504         if save_analysis(sess) {
 505             control.after_analysis.callback = box |state| {
 506                 time(state.session.time_passes(), "save analysis", || {
 507                     save::process_crate(state.tcx.unwrap(),
 508                                         state.expanded_crate.unwrap(),
 509                                         state.analysis.unwrap(),
 510                                         state.crate_name.unwrap(),
 511                                         DumpHandler::new(save_analysis_format(state.session),
 512                                                          state.out_dir,
 513                                                          state.crate_name.unwrap()))
 514                 });
 515             };
 516             control.after_analysis.run_callback_on_error = true;
 517             control.make_glob_map = resolve::MakeGlobMap::Yes;
 518         }
 519
 520         if sess.print_fuel_crate.is_some() {
 521             let old_callback = control.compilation_done.callback;
 522             control.compilation_done.callback = box move |state| {
 523                 old_callback(state);
 524                 let sess = state.session;
 525                 println!("Fuel used by {}: {}",
 526                     sess.print_fuel_crate.as_ref().unwrap(),
 527                     sess.print_fuel.get());
 528             }
 529         }
 530         control
 531     }
 532 }
 533
 534 fn save_analysis(sess: &Session) -> bool {
 535     sess.opts.debugging_opts.save_analysis ||
 536     sess.opts.debugging_opts.save_analysis_csv ||
 537     sess.opts.debugging_opts.save_analysis_api
 538 }
 539
 540 fn save_analysis_format(sess: &Session) -> save::Format {
 541     if sess.opts.debugging_opts.save_analysis {
 542         save::Format::Json
 543     } else if sess.opts.debugging_opts.save_analysis_csv {
 544         save::Format::Csv
 545     } else if sess.opts.debugging_opts.save_analysis_api {
 546         save::Format::JsonApi
 547     } else {
 548         unreachable!();
 549     }
 550 }
 551
 552 impl RustcDefaultCalls {
 553     pub fn list_metadata(sess: &Session, matches: &getopts::Matches, input: &Input) -> Compilation {
 554         let r = matches.opt_strs("Z");
 555         if r.contains(&("ls".to_string())) {
 556             match input {
 557                 &Input::File(ref ifile) => {
 558                     let path = &(*ifile);
 559                     let mut v = Vec::new();
 560                     locator::list_file_metadata(&sess.target.target, path, &mut v).unwrap();
 561                     println!("{}", String::from_utf8(v).unwrap());
 562                 }
 563                 &Input::Str { .. } => {
 564                     early_error(ErrorOutputType::default(), "cannot list metadata for stdin");
 565                 }
 566             }
 567             return Compilation::Stop;
 568         }
 569
 570         return Compilation::Continue;
 571     }
 572
 573
 574     fn print_crate_info(sess: &Session,
 575                         input: Option<&Input>,
 576                         odir: &Option<PathBuf>,
 577                         ofile: &Option<PathBuf>)
 578                         -> Compilation {
 579         if sess.opts.prints.is_empty() {
 580             return Compilation::Continue;
 581         }
 582
 583         let attrs = match input {
 584             None => None,
 585             Some(input) => {
 586                 let result = parse_crate_attrs(sess, input);
 587                 match result {
 588                     Ok(attrs) => Some(attrs),
 589                     Err(mut parse_error) => {
 590                         parse_error.emit();
 591                         return Compilation::Stop;
 592                     }
 593                 }
 594             }
 595         };
 596         for req in &sess.opts.prints {
 597             match *req {
 598                 PrintRequest::TargetList => {
 599                     let mut targets = rustc_back::target::get_targets().collect::<Vec<String>>();
 600                     targets.sort();
 601                     println!("{}", targets.join("\n"));
 602                 },
 603                 PrintRequest::Sysroot => println!("{}", sess.sysroot().display()),
 604                 PrintRequest::TargetSpec => println!("{}", sess.target.target.to_json().pretty()),
 605                 PrintRequest::FileNames |
 606                 PrintRequest::CrateName => {
 607                     let input = match input {
 608                         Some(input) => input,
 609                         None => early_error(ErrorOutputType::default(), "no input file provided"),
 610                     };
 611                     let attrs = attrs.as_ref().unwrap();
 612                     let t_outputs = driver::build_output_filenames(input, odir, ofile, attrs, sess);
 613                     let id = link::find_crate_name(Some(sess), attrs, input);
 614                     if *req == PrintRequest::CrateName {
 615                         println!("{}", id);
 616                         continue;
 617                     }
 618                     let crate_types = driver::collect_crate_types(sess, attrs);
 619                     for &style in &crate_types {
 620                         let fname = link::filename_for_input(sess, style, &id, &t_outputs);
 621                         println!("{}",
 622                                  fname.file_name()
 623                                       .unwrap()
 624                                       .to_string_lossy());
 625                     }
 626                 }
 627                 PrintRequest::Cfg => {
 628                     let allow_unstable_cfg = UnstableFeatures::from_environment()
 629                         .is_nightly_build();
 630
 631                     let mut cfgs = Vec::new();
 632                     for &(name, ref value) in sess.parse_sess.config.iter() {
 633                         let gated_cfg = GatedCfg::gate(&ast::MetaItem {
 634                             name: name,
 635                             node: ast::MetaItemKind::Word,
 636                             span: DUMMY_SP,
 637                         });
 638                         if !allow_unstable_cfg && gated_cfg.is_some() {
 639                             continue;
 640                         }
 641
 642                         cfgs.push(if let &Some(ref value) = value {
 643                             format!("{}=\"{}\"", name, value)
 644                         } else {
 645                             format!("{}", name)
 646                         });
 647                     }
 648
 649                     cfgs.sort();
 650                     for cfg in cfgs {
 651                         println!("{}", cfg);
 652                     }
 653                 }
 654                 PrintRequest::TargetCPUs => {
 655                     let tm = create_target_machine(sess);
 656                     unsafe { llvm::LLVMRustPrintTargetCPUs(tm); }
 657                 }
 658                 PrintRequest::TargetFeatures => {
 659                     let tm = create_target_machine(sess);
 660                     unsafe { llvm::LLVMRustPrintTargetFeatures(tm); }
 661                 }
 662                 PrintRequest::RelocationModels => {
 663                     println!("Available relocation models:");
 664                     for &(name, _) in RELOC_MODEL_ARGS.iter() {
 665                         println!("    {}", name);
 666                     }
 667                     println!("");
 668                 }
 669                 PrintRequest::CodeModels => {
 670                     println!("Available code models:");
 671                     for &(name, _) in CODE_GEN_MODEL_ARGS.iter(){
 672                         println!("    {}", name);
 673                     }
 674                     println!("");
 675                 }
 676             }
 677         }
 678         return Compilation::Stop;
 679     }
 680 }
 681
 682 /// Returns a version string such as "0.12.0-dev".
 683 pub fn release_str() -> Option<&'static str> {
 684     option_env!("CFG_RELEASE")
 685 }
 686
 687 /// Returns the full SHA1 hash of HEAD of the Git repo from which rustc was built.
 688 pub fn commit_hash_str() -> Option<&'static str> {
 689     option_env!("CFG_VER_HASH")
 690 }
 691
 692 /// Returns the "commit date" of HEAD of the Git repo from which rustc was built as a static string.
 693 pub fn commit_date_str() -> Option<&'static str> {
 694     option_env!("CFG_VER_DATE")
 695 }
 696
 697 /// Prints version information
 698 pub fn version(binary: &str, matches: &getopts::Matches) {
 699     let verbose = matches.opt_present("verbose");
 700
 701     println!("{} {}",
 702              binary,
 703              option_env!("CFG_VERSION").unwrap_or("unknown version"));
 704     if verbose {
 705         fn unw(x: Option<&str>) -> &str {
 706             x.unwrap_or("unknown")
 707         }
 708         println!("binary: {}", binary);
 709         println!("commit-hash: {}", unw(commit_hash_str()));
 710         println!("commit-date: {}", unw(commit_date_str()));
 711         println!("host: {}", config::host_triple());
 712         println!("release: {}", unw(release_str()));
 713         unsafe {
 714             println!("LLVM version: {}.{}",
 715                      llvm::LLVMRustVersionMajor(), llvm::LLVMRustVersionMinor());
 716         }
 717     }
 718 }
 719
 720 fn usage(verbose: bool, include_unstable_options: bool) {
 721     let groups = if verbose {
 722         config::rustc_optgroups()
 723     } else {
 724         config::rustc_short_optgroups()
 725     };
 726     let groups: Vec<_> = groups.into_iter()
 727                                .filter(|x| include_unstable_options || x.is_stable())
 728                                .map(|x| x.opt_group)
 729                                .collect();
 730     let message = format!("Usage: rustc [OPTIONS] INPUT");
 731     let extra_help = if verbose {
 732         ""
 733     } else {
 734         "\n    --help -v           Print the full set of options rustc accepts"
 735     };
 736     println!("{}\nAdditional help:
 737     -C help             Print codegen options
 738     -W help             \
 739               Print 'lint' options and default settings
 740     -Z help             Print internal \
 741               options for debugging rustc{}\n",
 742              getopts::usage(&message, &groups),
 743              extra_help);
 744 }
 745
 746 fn describe_lints(lint_store: &lint::LintStore, loaded_plugins: bool) {
 747     println!("
 748 Available lint options:
 749     -W <foo>           Warn about <foo>
 750     -A <foo>           \
 751               Allow <foo>
 752     -D <foo>           Deny <foo>
 753     -F <foo>           Forbid <foo> \
 754               (deny <foo> and all attempts to override)
 755
 756 ");
 757
 758     fn sort_lints(lints: Vec<(&'static Lint, bool)>) -> Vec<&'static Lint> {
 759         let mut lints: Vec<_> = lints.into_iter().map(|(x, _)| x).collect();
 760         lints.sort_by(|x: &&Lint, y: &&Lint| {
 761             match x.default_level.cmp(&y.default_level) {
 762                 // The sort doesn't case-fold but it's doubtful we care.
 763                 Equal => x.name.cmp(y.name),
 764                 r => r,
 765             }
 766         });
 767         lints
 768     }
 769
 770     fn sort_lint_groups(lints: Vec<(&'static str, Vec<lint::LintId>, bool)>)
 771                         -> Vec<(&'static str, Vec<lint::LintId>)> {
 772         let mut lints: Vec<_> = lints.into_iter().map(|(x, y, _)| (x, y)).collect();
 773         lints.sort_by(|&(x, _): &(&'static str, Vec<lint::LintId>),
 774                        &(y, _): &(&'static str, Vec<lint::LintId>)| {
 775             x.cmp(y)
 776         });
 777         lints
 778     }
 779
 780     let (plugin, builtin): (Vec<_>, _) = lint_store.get_lints()
 781                                                    .iter()
 782                                                    .cloned()
 783                                                    .partition(|&(_, p)| p);
 784     let plugin = sort_lints(plugin);
 785     let builtin = sort_lints(builtin);
 786
 787     let (plugin_groups, builtin_groups): (Vec<_>, _) = lint_store.get_lint_groups()
 788                                                                  .iter()
 789                                                                  .cloned()
 790                                                                  .partition(|&(.., p)| p);
 791     let plugin_groups = sort_lint_groups(plugin_groups);
 792     let builtin_groups = sort_lint_groups(builtin_groups);
 793
 794     let max_name_len = plugin.iter()
 795                              .chain(&builtin)
 796                              .map(|&s| s.name.chars().count())
 797                              .max()
 798                              .unwrap_or(0);
 799     let padded = |x: &str| {
 800         let mut s = repeat(" ")
 801                         .take(max_name_len - x.chars().count())
 802                         .collect::<String>();
 803         s.push_str(x);
 804         s
 805     };
 806
 807     println!("Lint checks provided by rustc:\n");
 808     println!("    {}  {:7.7}  {}", padded("name"), "default", "meaning");
 809     println!("    {}  {:7.7}  {}", padded("----"), "-------", "-------");
 810
 811     let print_lints = |lints: Vec<&Lint>| {
 812         for lint in lints {
 813             let name = lint.name_lower().replace("_", "-");
 814             println!("    {}  {:7.7}  {}",
 815                      padded(&name),
 816                      lint.default_level.as_str(),
 817                      lint.desc);
 818         }
 819         println!("\n");
 820     };
 821
 822     print_lints(builtin);
 823
 824
 825
 826     let max_name_len = max("warnings".len(),
 827                            plugin_groups.iter()
 828                                         .chain(&builtin_groups)
 829                                         .map(|&(s, _)| s.chars().count())
 830                                         .max()
 831                                         .unwrap_or(0));
 832
 833     let padded = |x: &str| {
 834         let mut s = repeat(" ")
 835                         .take(max_name_len - x.chars().count())
 836                         .collect::<String>();
 837         s.push_str(x);
 838         s
 839     };
 840
 841     println!("Lint groups provided by rustc:\n");
 842     println!("    {}  {}", padded("name"), "sub-lints");
 843     println!("    {}  {}", padded("----"), "---------");
 844     println!("    {}  {}", padded("warnings"), "all built-in lints");
 845
 846     let print_lint_groups = |lints: Vec<(&'static str, Vec<lint::LintId>)>| {
 847         for (name, to) in lints {
 848             let name = name.to_lowercase().replace("_", "-");
 849             let desc = to.into_iter()
 850                          .map(|x| x.to_string().replace("_", "-"))
 851                          .collect::<Vec<String>>()
 852                          .join(", ");
 853             println!("    {}  {}", padded(&name), desc);
 854         }
 855         println!("\n");
 856     };
 857
 858     print_lint_groups(builtin_groups);
 859
 860     match (loaded_plugins, plugin.len(), plugin_groups.len()) {
 861         (false, 0, _) | (false, _, 0) => {
 862             println!("Compiler plugins can provide additional lints and lint groups. To see a \
 863                       listing of these, re-run `rustc -W help` with a crate filename.");
 864         }
 865         (false, ..) => panic!("didn't load lint plugins but got them anyway!"),
 866         (true, 0, 0) => println!("This crate does not load any lint plugins or lint groups."),
 867         (true, l, g) => {
 868             if l > 0 {
 869                 println!("Lint checks provided by plugins loaded by this crate:\n");
 870                 print_lints(plugin);
 871             }
 872             if g > 0 {
 873                 println!("Lint groups provided by plugins loaded by this crate:\n");
 874                 print_lint_groups(plugin_groups);
 875             }
 876         }
 877     }
 878 }
 879
 880 fn describe_debug_flags() {
 881     println!("\nAvailable debug options:\n");
 882     print_flag_list("-Z", config::DB_OPTIONS);
 883 }
 884
 885 fn describe_codegen_flags() {
 886     println!("\nAvailable codegen options:\n");
 887     print_flag_list("-C", config::CG_OPTIONS);
 888 }
 889
 890 fn print_flag_list<T>(cmdline_opt: &str,
 891                       flag_list: &[(&'static str, T, Option<&'static str>, &'static str)]) {
 892     let max_len = flag_list.iter()
 893                            .map(|&(name, _, opt_type_desc, _)| {
 894                                let extra_len = match opt_type_desc {
 895                                    Some(..) => 4,
 896                                    None => 0,
 897                                };
 898                                name.chars().count() + extra_len
 899                            })
 900                            .max()
 901                            .unwrap_or(0);
 902
 903     for &(name, _, opt_type_desc, desc) in flag_list {
 904         let (width, extra) = match opt_type_desc {
 905             Some(..) => (max_len - 4, "=val"),
 906             None => (max_len, ""),
 907         };
 908         println!("    {} {:>width$}{} -- {}",
 909                  cmdline_opt,
 910                  name.replace("_", "-"),
 911                  extra,
 912                  desc,
 913                  width = width);
 914     }
 915 }
 916
 917 /// Process command line options. Emits messages as appropriate. If compilation
 918 /// should continue, returns a getopts::Matches object parsed from args,
 919 /// otherwise returns None.
 920 ///
 921 /// The compiler's handling of options is a little complicated as it ties into
 922 /// our stability story, and it's even *more* complicated by historical
 923 /// accidents. The current intention of each compiler option is to have one of
 924 /// three modes:
 925 ///
 926 /// 1. An option is stable and can be used everywhere.
 927 /// 2. An option is unstable, but was historically allowed on the stable
 928 ///    channel.
 929 /// 3. An option is unstable, and can only be used on nightly.
 930 ///
 931 /// Like unstable library and language features, however, unstable options have
 932 /// always required a form of "opt in" to indicate that you're using them. This
 933 /// provides the easy ability to scan a code base to check to see if anything
 934 /// unstable is being used. Currently, this "opt in" is the `-Z` "zed" flag.
 935 ///
 936 /// All options behind `-Z` are considered unstable by default. Other top-level
 937 /// options can also be considered unstable, and they were unlocked through the
 938 /// `-Z unstable-options` flag. Note that `-Z` remains to be the root of
 939 /// instability in both cases, though.
 940 ///
 941 /// So with all that in mind, the comments below have some more detail about the
 942 /// contortions done here to get things to work out correctly.
 943 pub fn handle_options(args: &[String]) -> Option<getopts::Matches> {
 944     // Throw away the first argument, the name of the binary
 945     let args = &args[1..];
 946
 947     if args.is_empty() {
 948         // user did not write `-v` nor `-Z unstable-options`, so do not
 949         // include that extra information.
 950         usage(false, false);
 951         return None;
 952     }
 953
 954     // Parse with *all* options defined in the compiler, we don't worry about
 955     // option stability here we just want to parse as much as possible.
 956     let all_groups: Vec<getopts::OptGroup> = config::rustc_optgroups()
 957                                                  .into_iter()
 958                                                  .map(|x| x.opt_group)
 959                                                  .collect();
 960     let matches = match getopts::getopts(&args, &all_groups) {
 961         Ok(m) => m,
 962         Err(f) => early_error(ErrorOutputType::default(), &f.to_string()),
 963     };
 964
 965     // For all options we just parsed, we check a few aspects:
 966     //
 967     // * If the option is stable, we're all good
 968     // * If the option wasn't passed, we're all good
 969     // * If `-Z unstable-options` wasn't passed (and we're not a -Z option
 970     //   ourselves), then we require the `-Z unstable-options` flag to unlock
 971     //   this option that was passed.
 972     // * If we're a nightly compiler, then unstable options are now unlocked, so
 973     //   we're good to go.
 974     // * Otherwise, if we're a truly unstable option then we generate an error
 975     //   (unstable option being used on stable)
 976     // * If we're a historically stable-but-should-be-unstable option then we
 977     //   emit a warning that we're going to turn this into an error soon.
 978     nightly_options::check_nightly_options(&matches, &config::rustc_optgroups());
 979
 980     if matches.opt_present("h") || matches.opt_present("help") {
 981         // Only show unstable options in --help if we *really* accept unstable
 982         // options, which catches the case where we got `-Z unstable-options` on
 983         // the stable channel of Rust which was accidentally allowed
 984         // historically.
 985         usage(matches.opt_present("verbose"),
 986               nightly_options::is_unstable_enabled(&matches));
 987         return None;
 988     }
 989
 990     // Don't handle -W help here, because we might first load plugins.
 991     let r = matches.opt_strs("Z");
 992     if r.iter().any(|x| *x == "help") {
 993         describe_debug_flags();
 994         return None;
 995     }
 996
 997     let cg_flags = matches.opt_strs("C");
 998     if cg_flags.iter().any(|x| *x == "help") {
 999         describe_codegen_flags();
1000         return None;
1001     }
1002
1003     if cg_flags.iter().any(|x| *x == "no-stack-check") {
1004         early_warn(ErrorOutputType::default(),
1005                    "the --no-stack-check flag is deprecated and does nothing");
1006     }
1007
1008     if cg_flags.contains(&"passes=list".to_string()) {
1009         unsafe {
1010             ::llvm::LLVMRustPrintPasses();
1011         }
1012         return None;
1013     }
1014
1015     if matches.opt_present("version") {
1016         version("rustc", &matches);
1017         return None;
1018     }
1019
1020     Some(matches)
1021 }
1022
1023 fn parse_crate_attrs<'a>(sess: &'a Session, input: &Input) -> PResult<'a, Vec<ast::Attribute>> {
1024     match *input {
1025         Input::File(ref ifile) => {
1026             parse::parse_crate_attrs_from_file(ifile, &sess.parse_sess)
1027         }
1028         Input::Str { ref name, ref input } => {
1029             parse::parse_crate_attrs_from_source_str(name.clone(), input.clone(), &sess.parse_sess)
1030         }
1031     }
1032 }
1033
1034 /// Runs `f` in a suitable thread for running `rustc`; returns a
1035 /// `Result` with either the return value of `f` or -- if a panic
1036 /// occurs -- the panic value.
1037 pub fn in_rustc_thread<F, R>(f: F) -> Result<R, Box<Any + Send>>
1038     where F: FnOnce() -> R + Send + 'static,
1039           R: Send + 'static,
1040 {
1041     // Temporarily have stack size set to 16MB to deal with nom-using crates failing
1042     const STACK_SIZE: usize = 16 * 1024 * 1024; // 16MB
1043
1044     let mut cfg = thread::Builder::new().name("rustc".to_string());
1045
1046     // FIXME: Hacks on hacks. If the env is trying to override the stack size
1047     // then *don't* set it explicitly.
1048     if env::var_os("RUST_MIN_STACK").is_none() {
1049         cfg = cfg.stack_size(STACK_SIZE);
1050     }
1051
1052     let thread = cfg.spawn(f);
1053     thread.unwrap().join()
1054 }
1055
1056 /// Run a procedure which will detect panics in the compiler and print nicer
1057 /// error messages rather than just failing the test.
1058 ///
1059 /// The diagnostic emitter yielded to the procedure should be used for reporting
1060 /// errors of the compiler.
1061 pub fn monitor<F: FnOnce() + Send + 'static>(f: F) {
1062     struct Sink(Arc<Mutex<Vec<u8>>>);
1063     impl Write for Sink {
1064         fn write(&mut self, data: &[u8]) -> io::Result<usize> {
1065             Write::write(&mut *self.0.lock().unwrap(), data)
1066         }
1067         fn flush(&mut self) -> io::Result<()> {
1068             Ok(())
1069         }
1070     }
1071
1072     let data = Arc::new(Mutex::new(Vec::new()));
1073     let err = Sink(data.clone());
1074
1075     let result = in_rustc_thread(move || {
1076         io::set_panic(Some(box err));
1077         f()
1078     });
1079
1080     if let Err(value) = result {
1081         // Thread panicked without emitting a fatal diagnostic
1082         if !value.is::<errors::FatalError>() {
1083             let emitter =
1084                 Box::new(errors::emitter::EmitterWriter::stderr(errors::ColorConfig::Auto, None));
1085             let handler = errors::Handler::with_emitter(true, false, emitter);
1086
1087             // a .span_bug or .bug call has already printed what
1088             // it wants to print.
1089             if !value.is::<errors::ExplicitBug>() {
1090                 handler.emit(&MultiSpan::new(),
1091                              "unexpected panic",
1092                              errors::Level::Bug);
1093             }
1094
1095             let xs = ["the compiler unexpectedly panicked. this is a bug.".to_string(),
1096                       format!("we would appreciate a bug report: {}", BUG_REPORT_URL)];
1097             for note in &xs {
1098                 handler.emit(&MultiSpan::new(),
1099                              &note,
1100                              errors::Level::Note);
1101             }
1102             if match env::var_os("RUST_BACKTRACE") {
1103                 Some(val) => &val != "0",
1104                 None => false,
1105             } {
1106                 handler.emit(&MultiSpan::new(),
1107                              "run with `RUST_BACKTRACE=1` for a backtrace",
1108                              errors::Level::Note);
1109             }
1110
1111             writeln!(io::stderr(), "{}", str::from_utf8(&data.lock().unwrap()).unwrap()).unwrap();
1112         }
1113
1114         exit_on_err();
1115     }
1116 }
1117
1118 fn exit_on_err() -> ! {
1119     // Panic so the process returns a failure code, but don't pollute the
1120     // output with some unnecessary panic messages, we've already
1121     // printed everything that we needed to.
1122     io::set_panic(Some(box io::sink()));
1123     panic!();
1124 }
1125
1126 pub fn diagnostics_registry() -> errors::registry::Registry {
1127     use errors::registry::Registry;
1128
1129     let mut all_errors = Vec::new();
1130     all_errors.extend_from_slice(&rustc::DIAGNOSTICS);
1131     all_errors.extend_from_slice(&rustc_typeck::DIAGNOSTICS);
1132     all_errors.extend_from_slice(&rustc_borrowck::DIAGNOSTICS);
1133     all_errors.extend_from_slice(&rustc_resolve::DIAGNOSTICS);
1134     all_errors.extend_from_slice(&rustc_privacy::DIAGNOSTICS);
1135     all_errors.extend_from_slice(&rustc_trans::DIAGNOSTICS);
1136     all_errors.extend_from_slice(&rustc_const_eval::DIAGNOSTICS);
1137     all_errors.extend_from_slice(&rustc_metadata::DIAGNOSTICS);
1138
1139     Registry::new(&all_errors)
1140 }
1141
1142 pub fn main() {
1143     env_logger::init().unwrap();
1144     let result = run(|| run_compiler(&env::args().collect::<Vec<_>>(),
1145                                      &mut RustcDefaultCalls,
1146                                      None,
1147                                      None));
1148     process::exit(result as i32);
1149 }