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
  35 extern crate arena;
  36 extern crate flate;
  37 extern crate getopts;
  38 extern crate graphviz;
  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_errors as errors;
  45 extern crate rustc_passes;
  46 extern crate rustc_lint;
  47 extern crate rustc_plugin;
  48 extern crate rustc_privacy;
  49 extern crate rustc_incremental;
  50 extern crate rustc_metadata;
  51 extern crate rustc_mir;
  52 extern crate rustc_resolve;
  53 extern crate rustc_save_analysis;
  54 extern crate rustc_trans;
  55 extern crate rustc_typeck;
  56 extern crate serialize;
  57 extern crate rustc_llvm as llvm;
  58 #[macro_use]
  59 extern crate log;
  60 #[macro_use]
  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_trans::back::link;
  71 use rustc_trans::back::write::{create_target_machine, RELOC_MODEL_ARGS, CODE_GEN_MODEL_ARGS};
  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::attr::AttrMetaMethods;
  99 use syntax::codemap::{CodeMap, FileLoader, RealFileLoader};
 100 use syntax::feature_gate::{GatedCfg, UnstableFeatures};
 101 use syntax::parse::{self, PResult};
 102 use syntax_pos::MultiSpan;
 103 use errors::emitter::Emitter;
 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                         let handler = errors::Handler::with_emitter(true, false, Box::new(emitter));
 146                         handler.emit(&MultiSpan::new(),
 147                                      &abort_msg(err_count),
 148                                      errors::Level::Fatal);
 149                         exit_on_err();
 150                     }
 151                 }
 152             }
 153         }
 154     });
 155     0
 156 }
 157
 158 pub fn run_compiler<'a>(args: &[String],
 159                         callbacks: &mut CompilerCalls<'a>)
 160                         -> (CompileResult, Option<Session>) {
 161     run_compiler_with_file_loader(args, callbacks, box RealFileLoader)
 162 }
 163
 164 // Parse args and run the compiler. This is the primary entry point for rustc.
 165 // See comments on CompilerCalls below for details about the callbacks argument.
 166 // The FileLoader provides a way to load files from sources other than the file system.
 167 pub fn run_compiler_with_file_loader<'a, L>(args: &[String],
 168                                             callbacks: &mut CompilerCalls<'a>,
 169                                             loader: Box<L>)
 170                                             -> (CompileResult, Option<Session>)
 171     where L: FileLoader + 'static {
 172     macro_rules! do_or_return {($expr: expr, $sess: expr) => {
 173         match $expr {
 174             Compilation::Stop => return (Ok(()), $sess),
 175             Compilation::Continue => {}
 176         }
 177     }}
 178
 179     let matches = match handle_options(args) {
 180         Some(matches) => matches,
 181         None => return (Ok(()), None),
 182     };
 183
 184     let sopts = config::build_session_options(&matches);
 185
 186     if sopts.debugging_opts.debug_llvm {
 187         unsafe { llvm::LLVMRustSetDebug(1); }
 188     }
 189
 190     let descriptions = diagnostics_registry();
 191
 192     do_or_return!(callbacks.early_callback(&matches,
 193                                            &sopts,
 194                                            &descriptions,
 195                                            sopts.error_format),
 196                                            None);
 197
 198     let (odir, ofile) = make_output(&matches);
 199     let (input, input_file_path) = match make_input(&matches.free) {
 200         Some((input, input_file_path)) => callbacks.some_input(input, input_file_path),
 201         None => match callbacks.no_input(&matches, &sopts, &odir, &ofile, &descriptions) {
 202             Some((input, input_file_path)) => (input, input_file_path),
 203             None => return (Ok(()), None),
 204         },
 205     };
 206
 207     let dep_graph = DepGraph::new(sopts.build_dep_graph());
 208     let cstore = Rc::new(CStore::new(&dep_graph));
 209     let codemap = Rc::new(CodeMap::with_file_loader(loader));
 210     let sess = session::build_session_with_codemap(sopts,
 211                                                    &dep_graph,
 212                                                    input_file_path,
 213                                                    descriptions,
 214                                                    cstore.clone(),
 215                                                    codemap);
 216     rustc_lint::register_builtins(&mut sess.lint_store.borrow_mut(), Some(&sess));
 217     let mut cfg = config::build_configuration(&sess);
 218     target_features::add_configuration(&mut cfg, &sess);
 219
 220     do_or_return!(callbacks.late_callback(&matches, &sess, &input, &odir, &ofile), Some(sess));
 221
 222     let plugins = sess.opts.debugging_opts.extra_plugins.clone();
 223     let control = callbacks.build_controller(&sess, &matches);
 224     (driver::compile_input(&sess, &cstore, cfg, &input, &odir, &ofile,
 225                            Some(plugins), &control),
 226      Some(sess))
 227 }
 228
 229 // Extract output directory and file from matches.
 230 fn make_output(matches: &getopts::Matches) -> (Option<PathBuf>, Option<PathBuf>) {
 231     let odir = matches.opt_str("out-dir").map(|o| PathBuf::from(&o));
 232     let ofile = matches.opt_str("o").map(|o| PathBuf::from(&o));
 233     (odir, ofile)
 234 }
 235
 236 // Extract input (string or file and optional path) from matches.
 237 fn make_input(free_matches: &[String]) -> Option<(Input, Option<PathBuf>)> {
 238     if free_matches.len() == 1 {
 239         let ifile = &free_matches[0][..];
 240         if ifile == "-" {
 241             let mut src = String::new();
 242             io::stdin().read_to_string(&mut src).unwrap();
 243             Some((Input::Str { name: driver::anon_src(), input: src },
 244                   None))
 245         } else {
 246             Some((Input::File(PathBuf::from(ifile)),
 247                   Some(PathBuf::from(ifile))))
 248         }
 249     } else {
 250         None
 251     }
 252 }
 253
 254 fn parse_pretty(sess: &Session,
 255                 matches: &getopts::Matches)
 256                 -> Option<(PpMode, Option<UserIdentifiedItem>)> {
 257     let pretty = if sess.opts.debugging_opts.unstable_options {
 258         matches.opt_default("pretty", "normal").map(|a| {
 259             // stable pretty-print variants only
 260             pretty::parse_pretty(sess, &a, false)
 261         })
 262     } else {
 263         None
 264     };
 265     if pretty.is_none() && sess.unstable_options() {
 266         matches.opt_str("unpretty").map(|a| {
 267             // extended with unstable pretty-print variants
 268             pretty::parse_pretty(sess, &a, true)
 269         })
 270     } else {
 271         pretty
 272     }
 273 }
 274
 275 // Whether to stop or continue compilation.
 276 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
 277 pub enum Compilation {
 278     Stop,
 279     Continue,
 280 }
 281
 282 impl Compilation {
 283     pub fn and_then<F: FnOnce() -> Compilation>(self, next: F) -> Compilation {
 284         match self {
 285             Compilation::Stop => Compilation::Stop,
 286             Compilation::Continue => next(),
 287         }
 288     }
 289 }
 290
 291 // A trait for customising the compilation process. Offers a number of hooks for
 292 // executing custom code or customising input.
 293 pub trait CompilerCalls<'a> {
 294     // Hook for a callback early in the process of handling arguments. This will
 295     // be called straight after options have been parsed but before anything
 296     // else (e.g., selecting input and output).
 297     fn early_callback(&mut self,
 298                       _: &getopts::Matches,
 299                       _: &config::Options,
 300                       _: &errors::registry::Registry,
 301                       _: ErrorOutputType)
 302                       -> Compilation {
 303         Compilation::Continue
 304     }
 305
 306     // Hook for a callback late in the process of handling arguments. This will
 307     // be called just before actual compilation starts (and before build_controller
 308     // is called), after all arguments etc. have been completely handled.
 309     fn late_callback(&mut self,
 310                      _: &getopts::Matches,
 311                      _: &Session,
 312                      _: &Input,
 313                      _: &Option<PathBuf>,
 314                      _: &Option<PathBuf>)
 315                      -> Compilation {
 316         Compilation::Continue
 317     }
 318
 319     // Called after we extract the input from the arguments. Gives the implementer
 320     // an opportunity to change the inputs or to add some custom input handling.
 321     // The default behaviour is to simply pass through the inputs.
 322     fn some_input(&mut self,
 323                   input: Input,
 324                   input_path: Option<PathBuf>)
 325                   -> (Input, Option<PathBuf>) {
 326         (input, input_path)
 327     }
 328
 329     // Called after we extract the input from the arguments if there is no valid
 330     // input. Gives the implementer an opportunity to supply alternate input (by
 331     // returning a Some value) or to add custom behaviour for this error such as
 332     // emitting error messages. Returning None will cause compilation to stop
 333     // at this point.
 334     fn no_input(&mut self,
 335                 _: &getopts::Matches,
 336                 _: &config::Options,
 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 fn check_cfg(sopts: &config::Options,
 379              output: ErrorOutputType) {
 380     let emitter: Box<Emitter> = match output {
 381         config::ErrorOutputType::HumanReadable(color_config) => {
 382             Box::new(errors::emitter::EmitterWriter::stderr(color_config, None))
 383         }
 384         config::ErrorOutputType::Json => Box::new(json::JsonEmitter::basic()),
 385     };
 386     let handler = errors::Handler::with_emitter(true, false, emitter);
 387
 388     let mut saw_invalid_predicate = false;
 389     for item in sopts.cfg.iter() {
 390         if item.is_meta_item_list() {
 391             saw_invalid_predicate = true;
 392             handler.emit(&MultiSpan::new(),
 393                          &format!("invalid predicate in --cfg command line argument: `{}`",
 394                                   item.name()),
 395                             errors::Level::Fatal);
 396         }
 397     }
 398
 399     if saw_invalid_predicate {
 400         panic!(errors::FatalError);
 401     }
 402 }
 403
 404 impl<'a> CompilerCalls<'a> for RustcDefaultCalls {
 405     fn early_callback(&mut self,
 406                       matches: &getopts::Matches,
 407                       sopts: &config::Options,
 408                       descriptions: &errors::registry::Registry,
 409                       output: ErrorOutputType)
 410                       -> Compilation {
 411         if let Some(ref code) = matches.opt_str("explain") {
 412             handle_explain(code, descriptions, output);
 413             return Compilation::Stop;
 414         }
 415
 416         check_cfg(sopts, output);
 417         Compilation::Continue
 418     }
 419
 420     fn no_input(&mut self,
 421                 matches: &getopts::Matches,
 422                 sopts: &config::Options,
 423                 odir: &Option<PathBuf>,
 424                 ofile: &Option<PathBuf>,
 425                 descriptions: &errors::registry::Registry)
 426                 -> Option<(Input, Option<PathBuf>)> {
 427         match matches.free.len() {
 428             0 => {
 429                 if sopts.describe_lints {
 430                     let mut ls = lint::LintStore::new();
 431                     rustc_lint::register_builtins(&mut ls, None);
 432                     describe_lints(&ls, false);
 433                     return None;
 434                 }
 435                 let dep_graph = DepGraph::new(sopts.build_dep_graph());
 436                 let cstore = Rc::new(CStore::new(&dep_graph));
 437                 let sess = build_session(sopts.clone(),
 438                     &dep_graph,
 439                     None,
 440                     descriptions.clone(),
 441                     cstore.clone());
 442                 rustc_lint::register_builtins(&mut sess.lint_store.borrow_mut(), Some(&sess));
 443                 let should_stop = RustcDefaultCalls::print_crate_info(&sess, None, odir, ofile);
 444                 if should_stop == Compilation::Stop {
 445                     return None;
 446                 }
 447                 early_error(sopts.error_format, "no input filename given");
 448             }
 449             1 => panic!("make_input should have provided valid inputs"),
 450             _ => early_error(sopts.error_format, "multiple input filenames provided"),
 451         }
 452
 453         None
 454     }
 455
 456     fn late_callback(&mut self,
 457                      matches: &getopts::Matches,
 458                      sess: &Session,
 459                      input: &Input,
 460                      odir: &Option<PathBuf>,
 461                      ofile: &Option<PathBuf>)
 462                      -> Compilation {
 463         RustcDefaultCalls::print_crate_info(sess, Some(input), odir, ofile)
 464             .and_then(|| RustcDefaultCalls::list_metadata(sess, matches, input))
 465     }
 466
 467     fn build_controller(&mut self,
 468                         sess: &Session,
 469                         matches: &getopts::Matches)
 470                         -> CompileController<'a> {
 471         let mut control = CompileController::basic();
 472
 473         if let Some((ppm, opt_uii)) = parse_pretty(sess, matches) {
 474             if ppm.needs_ast_map(&opt_uii) {
 475                 control.after_hir_lowering.stop = Compilation::Stop;
 476
 477                 control.after_parse.callback = box move |state| {
 478                     state.krate = Some(pretty::fold_crate(state.krate.take().unwrap(), ppm));
 479                 };
 480                 control.after_hir_lowering.callback = box move |state| {
 481                     pretty::print_after_hir_lowering(state.session,
 482                                                      state.ast_map.unwrap(),
 483                                                      state.analysis.unwrap(),
 484                                                      state.resolutions.unwrap(),
 485                                                      state.input,
 486                                                      &state.expanded_crate.take().unwrap(),
 487                                                      state.crate_name.unwrap(),
 488                                                      ppm,
 489                                                      state.arenas.unwrap(),
 490                                                      opt_uii.clone(),
 491                                                      state.out_file);
 492                 };
 493             } else {
 494                 control.after_parse.stop = Compilation::Stop;
 495
 496                 control.after_parse.callback = box move |state| {
 497                     let krate = pretty::fold_crate(state.krate.take().unwrap(), ppm);
 498                     pretty::print_after_parsing(state.session,
 499                                                 state.input,
 500                                                 &krate,
 501                                                 ppm,
 502                                                 state.out_file);
 503                 };
 504             }
 505
 506             return control;
 507         }
 508
 509         if sess.opts.parse_only || sess.opts.debugging_opts.show_span.is_some() ||
 510            sess.opts.debugging_opts.ast_json_noexpand {
 511             control.after_parse.stop = Compilation::Stop;
 512         }
 513
 514         if sess.opts.no_analysis || sess.opts.debugging_opts.ast_json {
 515             control.after_hir_lowering.stop = Compilation::Stop;
 516         }
 517
 518         if !sess.opts.output_types.keys().any(|&i| i == OutputType::Exe) {
 519             control.after_llvm.stop = Compilation::Stop;
 520         }
 521
 522         if save_analysis(sess) {
 523             control.after_analysis.callback = box |state| {
 524                 time(state.session.time_passes(), "save analysis", || {
 525                     save::process_crate(state.tcx.unwrap(),
 526                                         state.expanded_crate.unwrap(),
 527                                         state.analysis.unwrap(),
 528                                         state.crate_name.unwrap(),
 529                                         state.out_dir,
 530                                         save_analysis_format(state.session))
 531                 });
 532             };
 533             control.after_analysis.run_callback_on_error = true;
 534             control.make_glob_map = resolve::MakeGlobMap::Yes;
 535         }
 536
 537         control
 538     }
 539 }
 540
 541 fn save_analysis(sess: &Session) -> bool {
 542     sess.opts.debugging_opts.save_analysis ||
 543     sess.opts.debugging_opts.save_analysis_csv
 544 }
 545
 546 fn save_analysis_format(sess: &Session) -> save::Format {
 547     if sess.opts.debugging_opts.save_analysis {
 548         save::Format::Json
 549     } else if sess.opts.debugging_opts.save_analysis_csv {
 550         save::Format::Csv
 551     } else {
 552         unreachable!();
 553     }
 554 }
 555
 556 impl RustcDefaultCalls {
 557     pub fn list_metadata(sess: &Session, matches: &getopts::Matches, input: &Input) -> Compilation {
 558         let r = matches.opt_strs("Z");
 559         if r.contains(&("ls".to_string())) {
 560             match input {
 561                 &Input::File(ref ifile) => {
 562                     let path = &(*ifile);
 563                     let mut v = Vec::new();
 564                     loader::list_file_metadata(&sess.target.target, path, &mut v)
 565                         .unwrap();
 566                     println!("{}", String::from_utf8(v).unwrap());
 567                 }
 568                 &Input::Str { .. } => {
 569                     early_error(ErrorOutputType::default(), "cannot list metadata for stdin");
 570                 }
 571             }
 572             return Compilation::Stop;
 573         }
 574
 575         return Compilation::Continue;
 576     }
 577
 578
 579     fn print_crate_info(sess: &Session,
 580                         input: Option<&Input>,
 581                         odir: &Option<PathBuf>,
 582                         ofile: &Option<PathBuf>)
 583                         -> Compilation {
 584         if sess.opts.prints.is_empty() {
 585             return Compilation::Continue;
 586         }
 587
 588         let attrs = match input {
 589             None => None,
 590             Some(input) => {
 591                 let result = parse_crate_attrs(sess, input);
 592                 match result {
 593                     Ok(attrs) => Some(attrs),
 594                     Err(mut parse_error) => {
 595                         parse_error.emit();
 596                         return Compilation::Stop;
 597                     }
 598                 }
 599             }
 600         };
 601         for req in &sess.opts.prints {
 602             match *req {
 603                 PrintRequest::TargetList => {
 604                     let mut targets = rustc_back::target::get_targets().collect::<Vec<String>>();
 605                     targets.sort();
 606                     println!("{}", targets.join("\n"));
 607                 },
 608                 PrintRequest::Sysroot => println!("{}", sess.sysroot().display()),
 609                 PrintRequest::FileNames |
 610                 PrintRequest::CrateName => {
 611                     let input = match input {
 612                         Some(input) => input,
 613                         None => early_error(ErrorOutputType::default(), "no input file provided"),
 614                     };
 615                     let attrs = attrs.as_ref().unwrap();
 616                     let t_outputs = driver::build_output_filenames(input, odir, ofile, attrs, sess);
 617                     let id = link::find_crate_name(Some(sess), attrs, input);
 618                     if *req == PrintRequest::CrateName {
 619                         println!("{}", id);
 620                         continue;
 621                     }
 622                     let crate_types = driver::collect_crate_types(sess, attrs);
 623                     for &style in &crate_types {
 624                         let fname = link::filename_for_input(sess, style, &id, &t_outputs);
 625                         println!("{}",
 626                                  fname.file_name()
 627                                       .unwrap()
 628                                       .to_string_lossy());
 629                     }
 630                 }
 631                 PrintRequest::Cfg => {
 632                     let mut cfg = config::build_configuration(&sess);
 633                     target_features::add_configuration(&mut cfg, &sess);
 634
 635                     let allow_unstable_cfg = match get_unstable_features_setting() {
 636                         UnstableFeatures::Disallow => false,
 637                         _ => true,
 638                     };
 639
 640                     for cfg in cfg {
 641                         if !allow_unstable_cfg && GatedCfg::gate(&*cfg).is_some() {
 642                             continue;
 643                         }
 644                         if cfg.is_word() {
 645                             println!("{}", cfg.name());
 646                         } else if cfg.is_value_str() {
 647                             if let Some(s) = cfg.value_str() {
 648                                 println!("{}=\"{}\"", cfg.name(), s);
 649                             }
 650                         } else if cfg.is_meta_item_list() {
 651                             // Right now there are not and should not be any
 652                             // MetaItemKind::List items in the configuration returned by
 653                             // `build_configuration`.
 654                             panic!("MetaItemKind::List encountered in default cfg")
 655                         }
 656                     }
 657                 }
 658                 PrintRequest::TargetCPUs => {
 659                     let tm = create_target_machine(sess);
 660                     unsafe { llvm::LLVMRustPrintTargetCPUs(tm); }
 661                 }
 662                 PrintRequest::TargetFeatures => {
 663                     let tm = create_target_machine(sess);
 664                     unsafe { llvm::LLVMRustPrintTargetFeatures(tm); }
 665                 }
 666                 PrintRequest::RelocationModels => {
 667                     println!("Available relocation models:");
 668                     for &(name, _) in RELOC_MODEL_ARGS.iter() {
 669                         println!("    {}", name);
 670                     }
 671                     println!("");
 672                 }
 673                 PrintRequest::CodeModels => {
 674                     println!("Available code models:");
 675                     for &(name, _) in CODE_GEN_MODEL_ARGS.iter(){
 676                         println!("    {}", name);
 677                     }
 678                     println!("");
 679                 }
 680             }
 681         }
 682         return Compilation::Stop;
 683     }
 684 }
 685
 686 /// Returns a version string such as "0.12.0-dev".
 687 pub fn release_str() -> Option<&'static str> {
 688     option_env!("CFG_RELEASE")
 689 }
 690
 691 /// Returns the full SHA1 hash of HEAD of the Git repo from which rustc was built.
 692 pub fn commit_hash_str() -> Option<&'static str> {
 693     option_env!("CFG_VER_HASH")
 694 }
 695
 696 /// Returns the "commit date" of HEAD of the Git repo from which rustc was built as a static string.
 697 pub fn commit_date_str() -> Option<&'static str> {
 698     option_env!("CFG_VER_DATE")
 699 }
 700
 701 /// Prints version information
 702 pub fn version(binary: &str, matches: &getopts::Matches) {
 703     let verbose = matches.opt_present("verbose");
 704
 705     println!("{} {}",
 706              binary,
 707              option_env!("CFG_VERSION").unwrap_or("unknown version"));
 708     if verbose {
 709         fn unw(x: Option<&str>) -> &str {
 710             x.unwrap_or("unknown")
 711         }
 712         println!("binary: {}", binary);
 713         println!("commit-hash: {}", unw(commit_hash_str()));
 714         println!("commit-date: {}", unw(commit_date_str()));
 715         println!("host: {}", config::host_triple());
 716         println!("release: {}", unw(release_str()));
 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, and deny all overrides)
 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.as_str().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 complication 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.contains(&"passes=list".to_string()) {
1004         unsafe {
1005             ::llvm::LLVMRustPrintPasses();
1006         }
1007         return None;
1008     }
1009
1010     if matches.opt_present("version") {
1011         version("rustc", &matches);
1012         return None;
1013     }
1014
1015     Some(matches)
1016 }
1017
1018 fn parse_crate_attrs<'a>(sess: &'a Session, input: &Input) -> PResult<'a, Vec<ast::Attribute>> {
1019     match *input {
1020         Input::File(ref ifile) => {
1021             parse::parse_crate_attrs_from_file(ifile, Vec::new(), &sess.parse_sess)
1022         }
1023         Input::Str { ref name, ref input } => {
1024             parse::parse_crate_attrs_from_source_str(name.clone(),
1025                                                      input.clone(),
1026                                                      Vec::new(),
1027                                                      &sess.parse_sess)
1028         }
1029     }
1030 }
1031
1032 /// Run a procedure which will detect panics in the compiler and print nicer
1033 /// error messages rather than just failing the test.
1034 ///
1035 /// The diagnostic emitter yielded to the procedure should be used for reporting
1036 /// errors of the compiler.
1037 pub fn monitor<F: FnOnce() + Send + 'static>(f: F) {
1038     const STACK_SIZE: usize = 8 * 1024 * 1024; // 8MB
1039
1040     struct Sink(Arc<Mutex<Vec<u8>>>);
1041     impl Write for Sink {
1042         fn write(&mut self, data: &[u8]) -> io::Result<usize> {
1043             Write::write(&mut *self.0.lock().unwrap(), data)
1044         }
1045         fn flush(&mut self) -> io::Result<()> {
1046             Ok(())
1047         }
1048     }
1049
1050     let data = Arc::new(Mutex::new(Vec::new()));
1051     let err = Sink(data.clone());
1052
1053     let mut cfg = thread::Builder::new().name("rustc".to_string());
1054
1055     // FIXME: Hacks on hacks. If the env is trying to override the stack size
1056     // then *don't* set it explicitly.
1057     if env::var_os("RUST_MIN_STACK").is_none() {
1058         cfg = cfg.stack_size(STACK_SIZE);
1059     }
1060
1061     let thread = cfg.spawn(move || {
1062          io::set_panic(box err);
1063          f()
1064      });
1065
1066      if let Err(value) = thread.unwrap().join() {
1067         // Thread panicked without emitting a fatal diagnostic
1068         if !value.is::<errors::FatalError>() {
1069             let emitter =
1070                 Box::new(errors::emitter::EmitterWriter::stderr(errors::ColorConfig::Auto, None));
1071             let handler = errors::Handler::with_emitter(true, false, emitter);
1072
1073             // a .span_bug or .bug call has already printed what
1074             // it wants to print.
1075             if !value.is::<errors::ExplicitBug>() {
1076                 handler.emit(&MultiSpan::new(),
1077                              "unexpected panic",
1078                              errors::Level::Bug);
1079             }
1080
1081             let xs = ["the compiler unexpectedly panicked. this is a bug.".to_string(),
1082                       format!("we would appreciate a bug report: {}", BUG_REPORT_URL)];
1083             for note in &xs {
1084                 handler.emit(&MultiSpan::new(),
1085                              &note[..],
1086                              errors::Level::Note);
1087             }
1088             if match env::var_os("RUST_BACKTRACE") {
1089                 Some(val) => &val != "0",
1090                 None => false,
1091             } {
1092                 handler.emit(&MultiSpan::new(),
1093                              "run with `RUST_BACKTRACE=1` for a backtrace",
1094                              errors::Level::Note);
1095             }
1096
1097             println!("{}", str::from_utf8(&data.lock().unwrap()).unwrap());
1098         }
1099
1100         exit_on_err();
1101     }
1102 }
1103
1104 fn exit_on_err() -> ! {
1105     // Panic so the process returns a failure code, but don't pollute the
1106     // output with some unnecessary panic messages, we've already
1107     // printed everything that we needed to.
1108     io::set_panic(box io::sink());
1109     panic!();
1110 }
1111
1112 pub fn diagnostics_registry() -> errors::registry::Registry {
1113     use errors::registry::Registry;
1114
1115     let mut all_errors = Vec::new();
1116     all_errors.extend_from_slice(&rustc::DIAGNOSTICS);
1117     all_errors.extend_from_slice(&rustc_typeck::DIAGNOSTICS);
1118     all_errors.extend_from_slice(&rustc_borrowck::DIAGNOSTICS);
1119     all_errors.extend_from_slice(&rustc_resolve::DIAGNOSTICS);
1120     all_errors.extend_from_slice(&rustc_privacy::DIAGNOSTICS);
1121     all_errors.extend_from_slice(&rustc_trans::DIAGNOSTICS);
1122     all_errors.extend_from_slice(&rustc_const_eval::DIAGNOSTICS);
1123
1124     Registry::new(&all_errors)
1125 }
1126
1127 pub fn main() {
1128     let result = run(env::args().collect());
1129     process::exit(result as i32);
1130 }