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 #![doc(html_logo_url = "https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png",
  18       html_favicon_url = "https://doc.rust-lang.org/favicon.ico",
  19       html_root_url = "https://doc.rust-lang.org/nightly/")]
  20 #![deny(warnings)]
  21
  22 #![feature(box_syntax)]
  23 #![cfg_attr(unix, feature(libc))]
  24 #![feature(quote)]
  25 #![feature(rustc_diagnostic_macros)]
  26 #![feature(set_stdio)]
  27
  28 extern crate arena;
  29 extern crate getopts;
  30 extern crate graphviz;
  31 extern crate env_logger;
  32 #[cfg(unix)]
  33 extern crate libc;
  34 extern crate rustc;
  35 extern crate rustc_allocator;
  36 extern crate rustc_back;
  37 extern crate rustc_borrowck;
  38 extern crate rustc_const_eval;
  39 extern crate rustc_data_structures;
  40 extern crate rustc_errors as errors;
  41 extern crate rustc_passes;
  42 extern crate rustc_lint;
  43 extern crate rustc_plugin;
  44 extern crate rustc_privacy;
  45 extern crate rustc_incremental;
  46 extern crate rustc_metadata;
  47 extern crate rustc_mir;
  48 extern crate rustc_resolve;
  49 extern crate rustc_save_analysis;
  50 #[cfg(feature="llvm")]
  51 pub extern crate rustc_trans;
  52 extern crate rustc_trans_utils;
  53 extern crate rustc_typeck;
  54 extern crate serialize;
  55 #[macro_use]
  56 extern crate log;
  57 extern crate syntax;
  58 extern crate syntax_ext;
  59 extern crate syntax_pos;
  60
  61 use driver::CompileController;
  62 use pretty::{PpMode, UserIdentifiedItem};
  63
  64 use rustc_resolve as resolve;
  65 use rustc_save_analysis as save;
  66 use rustc_save_analysis::DumpHandler;
  67 use rustc::session::{self, config, Session, build_session, CompileResult};
  68 use rustc::session::CompileIncomplete;
  69 use rustc::session::config::{Input, PrintRequest, ErrorOutputType};
  70 use rustc::session::config::nightly_options;
  71 use rustc::session::{early_error, early_warn};
  72 use rustc::lint::Lint;
  73 use rustc::lint;
  74 use rustc::middle::cstore::CrateStore;
  75 use rustc_metadata::locator;
  76 use rustc_metadata::cstore::CStore;
  77 use rustc::util::common::{time, ErrorReported};
  78 use rustc_trans_utils::trans_crate::TransCrate;
  79
  80 use serialize::json::ToJson;
  81
  82 use std::any::Any;
  83 use std::cmp::max;
  84 use std::cmp::Ordering::Equal;
  85 use std::default::Default;
  86 use std::env;
  87 use std::ffi::OsString;
  88 use std::io::{self, Read, Write};
  89 use std::iter::repeat;
  90 use std::path::PathBuf;
  91 use std::process::{self, Command, Stdio};
  92 use std::rc::Rc;
  93 use std::str;
  94 use std::sync::{Arc, Mutex};
  95 use std::thread;
  96
  97 use syntax::ast;
  98 use syntax::codemap::{CodeMap, FileLoader, RealFileLoader};
  99 use syntax::feature_gate::{GatedCfg, UnstableFeatures};
 100 use syntax::parse::{self, PResult};
 101 use syntax_pos::{DUMMY_SP, MultiSpan, FileName};
 102
 103 #[cfg(test)]
 104 mod test;
 105
 106 pub mod profile;
 107 pub mod driver;
 108 pub mod pretty;
 109 mod derive_registrar;
 110
 111 pub mod target_features {
 112     use syntax::ast;
 113     use syntax::symbol::Symbol;
 114     use rustc::session::Session;
 115     use rustc_trans_utils::trans_crate::TransCrate;
 116
 117     /// Add `target_feature = "..."` cfgs for a variety of platform
 118     /// specific features (SSE, NEON etc.).
 119     ///
 120     /// This is performed by checking whether a whitelisted set of
 121     /// features is available on the target machine, by querying LLVM.
 122     pub fn add_configuration(cfg: &mut ast::CrateConfig, sess: &Session, trans: &TransCrate) {
 123         let tf = Symbol::intern("target_feature");
 124
 125         for feat in trans.target_features(sess) {
 126             cfg.insert((tf, Some(feat)));
 127         }
 128
 129         if sess.crt_static_feature() {
 130             cfg.insert((tf, Some(Symbol::intern("crt-static"))));
 131         }
 132     }
 133 }
 134
 135 const BUG_REPORT_URL: &'static str = "https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.\
 136                                       md#bug-reports";
 137
 138 pub fn abort_on_err<T>(result: Result<T, CompileIncomplete>, sess: &Session) -> T {
 139     match result {
 140         Err(CompileIncomplete::Errored(ErrorReported)) => {
 141             sess.abort_if_errors();
 142             panic!("error reported but abort_if_errors didn't abort???");
 143         }
 144         Err(CompileIncomplete::Stopped) => {
 145             sess.fatal("compilation terminated");
 146         }
 147         Ok(x) => x,
 148     }
 149 }
 150
 151 pub fn run<F>(run_compiler: F) -> isize
 152     where F: FnOnce() -> (CompileResult, Option<Session>) + Send + 'static
 153 {
 154     monitor(move || {
 155         let (result, session) = run_compiler();
 156         if let Err(CompileIncomplete::Errored(_)) = result {
 157             match session {
 158                 Some(sess) => {
 159                     sess.abort_if_errors();
 160                     panic!("error reported but abort_if_errors didn't abort???");
 161                 }
 162                 None => {
 163                     let emitter =
 164                         errors::emitter::EmitterWriter::stderr(errors::ColorConfig::Auto,
 165                                                                None,
 166                                                                true);
 167                     let handler = errors::Handler::with_emitter(true, false, Box::new(emitter));
 168                     handler.emit(&MultiSpan::new(),
 169                                  "aborting due to previous error(s)",
 170                                  errors::Level::Fatal);
 171                     exit_on_err();
 172                 }
 173             }
 174         }
 175     });
 176     0
 177 }
 178
 179 #[cfg(not(feature="llvm"))]
 180 pub use rustc_trans_utils::trans_crate::MetadataOnlyTransCrate as DefaultTransCrate;
 181 #[cfg(feature="llvm")]
 182 pub use rustc_trans::LlvmTransCrate as DefaultTransCrate;
 183
 184 #[cfg(not(feature="llvm"))]
 185 pub mod rustc_trans {
 186     pub use rustc_trans_utils::trans_crate::MetadataOnlyTransCrate as LlvmTransCrate;
 187
 188     pub fn print_version() {}
 189     pub fn print_passes() {}
 190 }
 191
 192 fn load_backend_from_dylib(sess: &Session, backend_name: &str) -> Box<TransCrate> {
 193     use std::path::Path;
 194     use rustc_metadata::dynamic_lib::DynamicLibrary;
 195
 196     match DynamicLibrary::open(Some(Path::new(backend_name))) {
 197         Ok(lib) => {
 198             unsafe {
 199                 let trans = {
 200                     let __rustc_codegen_backend: unsafe fn(&Session) -> Box<TransCrate>;
 201                     __rustc_codegen_backend = match lib.symbol("__rustc_codegen_backend") {
 202                         Ok(f) => ::std::mem::transmute::<*mut u8, _>(f),
 203                         Err(e) => sess.fatal(&format!("Couldnt load codegen backend as it\
 204                         doesn't export the __rustc_backend_new symbol: {:?}", e)),
 205                     };
 206                     __rustc_codegen_backend(sess)
 207                 };
 208                 ::std::mem::forget(lib);
 209                 trans
 210             }
 211         }
 212         Err(err) => {
 213             sess.fatal(&format!("Couldnt load codegen backend {:?}: {:?}", backend_name, err));
 214         }
 215     }
 216 }
 217
 218 pub fn get_trans(sess: &Session) -> Box<TransCrate> {
 219     let trans_name = sess.opts.debugging_opts.codegen_backend.clone();
 220     match trans_name.as_ref().map(|s|&**s) {
 221         None => DefaultTransCrate::new(&sess),
 222         Some("llvm") => rustc_trans::LlvmTransCrate::new(&sess),
 223         Some("metadata_only") => {
 224             rustc_trans_utils::trans_crate::MetadataOnlyTransCrate::new(&sess)
 225         }
 226         Some(filename) if filename.contains(".") => {
 227             load_backend_from_dylib(&sess, &filename)
 228         }
 229         Some(trans_name) => sess.fatal(&format!("Unknown codegen backend {}", trans_name)),
 230     }
 231 }
 232
 233 // Parse args and run the compiler. This is the primary entry point for rustc.
 234 // See comments on CompilerCalls below for details about the callbacks argument.
 235 // The FileLoader provides a way to load files from sources other than the file system.
 236 pub fn run_compiler<'a>(args: &[String],
 237                         callbacks: &mut CompilerCalls<'a>,
 238                         file_loader: Option<Box<FileLoader + 'static>>,
 239                         emitter_dest: Option<Box<Write + Send>>)
 240                         -> (CompileResult, Option<Session>)
 241 {
 242     macro_rules! do_or_return {($expr: expr, $sess: expr) => {
 243         match $expr {
 244             Compilation::Stop => return (Ok(()), $sess),
 245             Compilation::Continue => {}
 246         }
 247     }}
 248
 249     let matches = match handle_options(args) {
 250         Some(matches) => matches,
 251         None => return (Ok(()), None),
 252     };
 253
 254     let (sopts, cfg) = config::build_session_options_and_crate_config(&matches);
 255
 256     let descriptions = diagnostics_registry();
 257
 258     do_or_return!(callbacks.early_callback(&matches,
 259                                            &sopts,
 260                                            &cfg,
 261                                            &descriptions,
 262                                            sopts.error_format),
 263                                            None);
 264
 265     let (odir, ofile) = make_output(&matches);
 266     let (input, input_file_path) = match make_input(&matches.free) {
 267         Some((input, input_file_path)) => callbacks.some_input(input, input_file_path),
 268         None => match callbacks.no_input(&matches, &sopts, &cfg, &odir, &ofile, &descriptions) {
 269             Some((input, input_file_path)) => (input, input_file_path),
 270             None => return (Ok(()), None),
 271         },
 272     };
 273
 274     let loader = file_loader.unwrap_or(box RealFileLoader);
 275     let codemap = Rc::new(CodeMap::with_file_loader(loader, sopts.file_path_mapping()));
 276     let mut sess = session::build_session_with_codemap(
 277         sopts, input_file_path.clone(), descriptions, codemap, emitter_dest,
 278     );
 279
 280     let trans = get_trans(&sess);
 281
 282     rustc_lint::register_builtins(&mut sess.lint_store.borrow_mut(), Some(&sess));
 283
 284     let mut cfg = config::build_configuration(&sess, cfg);
 285     target_features::add_configuration(&mut cfg, &sess, &*trans);
 286     sess.parse_sess.config = cfg;
 287
 288     let plugins = sess.opts.debugging_opts.extra_plugins.clone();
 289
 290     let cstore = CStore::new(trans.metadata_loader());
 291
 292     do_or_return!(callbacks.late_callback(&*trans,
 293                                           &matches,
 294                                           &sess,
 295                                           &cstore,
 296                                           &input,
 297                                           &odir,
 298                                           &ofile), Some(sess));
 299
 300     let control = callbacks.build_controller(&sess, &matches);
 301
 302     (driver::compile_input(trans,
 303                            &sess,
 304                            &cstore,
 305                            &input_file_path,
 306                            &input,
 307                            &odir,
 308                            &ofile,
 309                            Some(plugins),
 310                            &control),
 311      Some(sess))
 312 }
 313
 314 // Extract output directory and file from matches.
 315 fn make_output(matches: &getopts::Matches) -> (Option<PathBuf>, Option<PathBuf>) {
 316     let odir = matches.opt_str("out-dir").map(|o| PathBuf::from(&o));
 317     let ofile = matches.opt_str("o").map(|o| PathBuf::from(&o));
 318     (odir, ofile)
 319 }
 320
 321 // Extract input (string or file and optional path) from matches.
 322 fn make_input(free_matches: &[String]) -> Option<(Input, Option<PathBuf>)> {
 323     if free_matches.len() == 1 {
 324         let ifile = &free_matches[0];
 325         if ifile == "-" {
 326             let mut src = String::new();
 327             io::stdin().read_to_string(&mut src).unwrap();
 328             Some((Input::Str { name: FileName::Anon, input: src },
 329                   None))
 330         } else {
 331             Some((Input::File(PathBuf::from(ifile)),
 332                   Some(PathBuf::from(ifile))))
 333         }
 334     } else {
 335         None
 336     }
 337 }
 338
 339 fn parse_pretty(sess: &Session,
 340                 matches: &getopts::Matches)
 341                 -> Option<(PpMode, Option<UserIdentifiedItem>)> {
 342     let pretty = if sess.opts.debugging_opts.unstable_options {
 343         matches.opt_default("pretty", "normal").map(|a| {
 344             // stable pretty-print variants only
 345             pretty::parse_pretty(sess, &a, false)
 346         })
 347     } else {
 348         None
 349     };
 350
 351     if pretty.is_none() {
 352         sess.opts.debugging_opts.unpretty.as_ref().map(|a| {
 353             // extended with unstable pretty-print variants
 354             pretty::parse_pretty(sess, &a, true)
 355         })
 356     } else {
 357         pretty
 358     }
 359 }
 360
 361 // Whether to stop or continue compilation.
 362 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
 363 pub enum Compilation {
 364     Stop,
 365     Continue,
 366 }
 367
 368 impl Compilation {
 369     pub fn and_then<F: FnOnce() -> Compilation>(self, next: F) -> Compilation {
 370         match self {
 371             Compilation::Stop => Compilation::Stop,
 372             Compilation::Continue => next(),
 373         }
 374     }
 375 }
 376
 377 // A trait for customising the compilation process. Offers a number of hooks for
 378 // executing custom code or customising input.
 379 pub trait CompilerCalls<'a> {
 380     // Hook for a callback early in the process of handling arguments. This will
 381     // be called straight after options have been parsed but before anything
 382     // else (e.g., selecting input and output).
 383     fn early_callback(&mut self,
 384                       _: &getopts::Matches,
 385                       _: &config::Options,
 386                       _: &ast::CrateConfig,
 387                       _: &errors::registry::Registry,
 388                       _: ErrorOutputType)
 389                       -> Compilation {
 390         Compilation::Continue
 391     }
 392
 393     // Hook for a callback late in the process of handling arguments. This will
 394     // be called just before actual compilation starts (and before build_controller
 395     // is called), after all arguments etc. have been completely handled.
 396     fn late_callback(&mut self,
 397                      _: &TransCrate,
 398                      _: &getopts::Matches,
 399                      _: &Session,
 400                      _: &CrateStore,
 401                      _: &Input,
 402                      _: &Option<PathBuf>,
 403                      _: &Option<PathBuf>)
 404                      -> Compilation {
 405         Compilation::Continue
 406     }
 407
 408     // Called after we extract the input from the arguments. Gives the implementer
 409     // an opportunity to change the inputs or to add some custom input handling.
 410     // The default behaviour is to simply pass through the inputs.
 411     fn some_input(&mut self,
 412                   input: Input,
 413                   input_path: Option<PathBuf>)
 414                   -> (Input, Option<PathBuf>) {
 415         (input, input_path)
 416     }
 417
 418     // Called after we extract the input from the arguments if there is no valid
 419     // input. Gives the implementer an opportunity to supply alternate input (by
 420     // returning a Some value) or to add custom behaviour for this error such as
 421     // emitting error messages. Returning None will cause compilation to stop
 422     // at this point.
 423     fn no_input(&mut self,
 424                 _: &getopts::Matches,
 425                 _: &config::Options,
 426                 _: &ast::CrateConfig,
 427                 _: &Option<PathBuf>,
 428                 _: &Option<PathBuf>,
 429                 _: &errors::registry::Registry)
 430                 -> Option<(Input, Option<PathBuf>)> {
 431         None
 432     }
 433
 434     // Create a CompilController struct for controlling the behaviour of
 435     // compilation.
 436     fn build_controller(&mut self, _: &Session, _: &getopts::Matches) -> CompileController<'a>;
 437 }
 438
 439 // CompilerCalls instance for a regular rustc build.
 440 #[derive(Copy, Clone)]
 441 pub struct RustcDefaultCalls;
 442
 443 // FIXME remove these and use winapi 0.3 instead
 444 // Duplicates: bootstrap/compile.rs, librustc_errors/emitter.rs
 445 #[cfg(unix)]
 446 fn stdout_isatty() -> bool {
 447     unsafe { libc::isatty(libc::STDOUT_FILENO) != 0 }
 448 }
 449
 450 #[cfg(windows)]
 451 fn stdout_isatty() -> bool {
 452     type DWORD = u32;
 453     type BOOL = i32;
 454     type HANDLE = *mut u8;
 455     type LPDWORD = *mut u32;
 456     const STD_OUTPUT_HANDLE: DWORD = -11i32 as DWORD;
 457     extern "system" {
 458         fn GetStdHandle(which: DWORD) -> HANDLE;
 459         fn GetConsoleMode(hConsoleHandle: HANDLE, lpMode: LPDWORD) -> BOOL;
 460     }
 461     unsafe {
 462         let handle = GetStdHandle(STD_OUTPUT_HANDLE);
 463         let mut out = 0;
 464         GetConsoleMode(handle, &mut out) != 0
 465     }
 466 }
 467
 468 fn handle_explain(code: &str,
 469                   descriptions: &errors::registry::Registry,
 470                   output: ErrorOutputType) {
 471     let normalised = if code.starts_with("E") {
 472         code.to_string()
 473     } else {
 474         format!("E{0:0>4}", code)
 475     };
 476     match descriptions.find_description(&normalised) {
 477         Some(ref description) => {
 478             let mut is_in_code_block = false;
 479             let mut text = String::new();
 480
 481             // Slice off the leading newline and print.
 482             for line in description[1..].lines() {
 483                 let indent_level = line.find(|c: char| !c.is_whitespace())
 484                     .unwrap_or_else(|| line.len());
 485                 let dedented_line = &line[indent_level..];
 486                 if dedented_line.starts_with("```") {
 487                     is_in_code_block = !is_in_code_block;
 488                     text.push_str(&line[..(indent_level+3)]);
 489                 } else if is_in_code_block && dedented_line.starts_with("# ") {
 490                     continue;
 491                 } else {
 492                     text.push_str(line);
 493                 }
 494                 text.push('\n');
 495             }
 496
 497             if stdout_isatty() {
 498                 show_content_with_pager(&text);
 499             } else {
 500                 print!("{}", text);
 501             }
 502         }
 503         None => {
 504             early_error(output, &format!("no extended information for {}", code));
 505         }
 506     }
 507 }
 508
 509 fn show_content_with_pager(content: &String) {
 510     let pager_name = env::var_os("PAGER").unwrap_or_else(|| if cfg!(windows) {
 511         OsString::from("more.com")
 512     } else {
 513         OsString::from("less")
 514     });
 515
 516     let mut fallback_to_println = false;
 517
 518     match Command::new(pager_name).stdin(Stdio::piped()).spawn() {
 519         Ok(mut pager) => {
 520             if let Some(pipe) = pager.stdin.as_mut() {
 521                 if pipe.write_all(content.as_bytes()).is_err() {
 522                     fallback_to_println = true;
 523                 }
 524             }
 525
 526             if pager.wait().is_err() {
 527                 fallback_to_println = true;
 528             }
 529         }
 530         Err(_) => {
 531             fallback_to_println = true;
 532         }
 533     }
 534
 535     // If pager fails for whatever reason, we should still print the content
 536     // to standard output
 537     if fallback_to_println {
 538         print!("{}", content);
 539     }
 540 }
 541
 542 impl<'a> CompilerCalls<'a> for RustcDefaultCalls {
 543     fn early_callback(&mut self,
 544                       matches: &getopts::Matches,
 545                       _: &config::Options,
 546                       _: &ast::CrateConfig,
 547                       descriptions: &errors::registry::Registry,
 548                       output: ErrorOutputType)
 549                       -> Compilation {
 550         if let Some(ref code) = matches.opt_str("explain") {
 551             handle_explain(code, descriptions, output);
 552             return Compilation::Stop;
 553         }
 554
 555         Compilation::Continue
 556     }
 557
 558     fn no_input(&mut self,
 559                 matches: &getopts::Matches,
 560                 sopts: &config::Options,
 561                 cfg: &ast::CrateConfig,
 562                 odir: &Option<PathBuf>,
 563                 ofile: &Option<PathBuf>,
 564                 descriptions: &errors::registry::Registry)
 565                 -> Option<(Input, Option<PathBuf>)> {
 566         match matches.free.len() {
 567             0 => {
 568                 if sopts.describe_lints {
 569                     let mut ls = lint::LintStore::new();
 570                     rustc_lint::register_builtins(&mut ls, None);
 571                     describe_lints(&ls, false);
 572                     return None;
 573                 }
 574                 let mut sess = build_session(sopts.clone(),
 575                     None,
 576                     descriptions.clone());
 577                 rustc_lint::register_builtins(&mut sess.lint_store.borrow_mut(), Some(&sess));
 578                 let mut cfg = config::build_configuration(&sess, cfg.clone());
 579                 let trans = get_trans(&sess);
 580                 target_features::add_configuration(&mut cfg, &sess, &*trans);
 581                 sess.parse_sess.config = cfg;
 582                 let should_stop = RustcDefaultCalls::print_crate_info(
 583                     &*trans,
 584                     &sess,
 585                     None,
 586                     odir,
 587                     ofile
 588                 );
 589
 590                 if should_stop == Compilation::Stop {
 591                     return None;
 592                 }
 593                 early_error(sopts.error_format, "no input filename given");
 594             }
 595             1 => panic!("make_input should have provided valid inputs"),
 596             _ => early_error(sopts.error_format, "multiple input filenames provided"),
 597         }
 598     }
 599
 600     fn late_callback(&mut self,
 601                      trans: &TransCrate,
 602                      matches: &getopts::Matches,
 603                      sess: &Session,
 604                      cstore: &CrateStore,
 605                      input: &Input,
 606                      odir: &Option<PathBuf>,
 607                      ofile: &Option<PathBuf>)
 608                      -> Compilation {
 609         RustcDefaultCalls::print_crate_info(trans, sess, Some(input), odir, ofile)
 610             .and_then(|| RustcDefaultCalls::list_metadata(sess, cstore, matches, input))
 611     }
 612
 613     fn build_controller(&mut self,
 614                         sess: &Session,
 615                         matches: &getopts::Matches)
 616                         -> CompileController<'a> {
 617         let mut control = CompileController::basic();
 618
 619         control.keep_ast = sess.opts.debugging_opts.keep_ast;
 620         control.continue_parse_after_error = sess.opts.debugging_opts.continue_parse_after_error;
 621
 622         if let Some((ppm, opt_uii)) = parse_pretty(sess, matches) {
 623             if ppm.needs_ast_map(&opt_uii) {
 624                 control.after_hir_lowering.stop = Compilation::Stop;
 625
 626                 control.after_parse.callback = box move |state| {
 627                     state.krate = Some(pretty::fold_crate(state.session,
 628                                                           state.krate.take().unwrap(),
 629                                                           ppm));
 630                 };
 631                 control.after_hir_lowering.callback = box move |state| {
 632                     pretty::print_after_hir_lowering(state.session,
 633                                                      state.cstore.unwrap(),
 634                                                      state.hir_map.unwrap(),
 635                                                      state.analysis.unwrap(),
 636                                                      state.resolutions.unwrap(),
 637                                                      state.input,
 638                                                      &state.expanded_crate.take().unwrap(),
 639                                                      state.crate_name.unwrap(),
 640                                                      ppm,
 641                                                      state.arenas.unwrap(),
 642                                                      state.output_filenames.unwrap(),
 643                                                      opt_uii.clone(),
 644                                                      state.out_file);
 645                 };
 646             } else {
 647                 control.after_parse.stop = Compilation::Stop;
 648
 649                 control.after_parse.callback = box move |state| {
 650                     let krate = pretty::fold_crate(state.session, state.krate.take().unwrap(), ppm);
 651                     pretty::print_after_parsing(state.session,
 652                                                 state.input,
 653                                                 &krate,
 654                                                 ppm,
 655                                                 state.out_file);
 656                 };
 657             }
 658
 659             return control;
 660         }
 661
 662         if sess.opts.debugging_opts.parse_only ||
 663            sess.opts.debugging_opts.show_span.is_some() ||
 664            sess.opts.debugging_opts.ast_json_noexpand {
 665             control.after_parse.stop = Compilation::Stop;
 666         }
 667
 668         if sess.opts.debugging_opts.no_analysis ||
 669            sess.opts.debugging_opts.ast_json {
 670             control.after_hir_lowering.stop = Compilation::Stop;
 671         }
 672
 673         if save_analysis(sess) {
 674             enable_save_analysis(&mut control);
 675         }
 676
 677         if sess.print_fuel_crate.is_some() {
 678             let old_callback = control.compilation_done.callback;
 679             control.compilation_done.callback = box move |state| {
 680                 old_callback(state);
 681                 let sess = state.session;
 682                 println!("Fuel used by {}: {}",
 683                     sess.print_fuel_crate.as_ref().unwrap(),
 684                     sess.print_fuel.get());
 685             }
 686         }
 687         control
 688     }
 689 }
 690
 691 pub fn enable_save_analysis(control: &mut CompileController) {
 692     control.keep_ast = true;
 693     control.after_analysis.callback = box |state| {
 694         time(state.session.time_passes(), "save analysis", || {
 695             save::process_crate(state.tcx.unwrap(),
 696                                 state.expanded_crate.unwrap(),
 697                                 state.analysis.unwrap(),
 698                                 state.crate_name.unwrap(),
 699                                 None,
 700                                 DumpHandler::new(state.out_dir,
 701                                                  state.crate_name.unwrap()))
 702         });
 703     };
 704     control.after_analysis.run_callback_on_error = true;
 705     control.make_glob_map = resolve::MakeGlobMap::Yes;
 706 }
 707
 708 fn save_analysis(sess: &Session) -> bool {
 709     sess.opts.debugging_opts.save_analysis
 710 }
 711
 712 impl RustcDefaultCalls {
 713     pub fn list_metadata(sess: &Session,
 714                          cstore: &CrateStore,
 715                          matches: &getopts::Matches,
 716                          input: &Input)
 717                          -> Compilation {
 718         let r = matches.opt_strs("Z");
 719         if r.contains(&("ls".to_string())) {
 720             match input {
 721                 &Input::File(ref ifile) => {
 722                     let path = &(*ifile);
 723                     let mut v = Vec::new();
 724                     locator::list_file_metadata(&sess.target.target,
 725                                                 path,
 726                                                 cstore.metadata_loader(),
 727                                                 &mut v)
 728                             .unwrap();
 729                     println!("{}", String::from_utf8(v).unwrap());
 730                 }
 731                 &Input::Str { .. } => {
 732                     early_error(ErrorOutputType::default(), "cannot list metadata for stdin");
 733                 }
 734             }
 735             return Compilation::Stop;
 736         }
 737
 738         return Compilation::Continue;
 739     }
 740
 741
 742     fn print_crate_info(trans: &TransCrate,
 743                         sess: &Session,
 744                         input: Option<&Input>,
 745                         odir: &Option<PathBuf>,
 746                         ofile: &Option<PathBuf>)
 747                         -> Compilation {
 748         use rustc::session::config::PrintRequest::*;
 749         // PrintRequest::NativeStaticLibs is special - printed during linking
 750         // (empty iterator returns true)
 751         if sess.opts.prints.iter().all(|&p| p==PrintRequest::NativeStaticLibs) {
 752             return Compilation::Continue;
 753         }
 754
 755         let attrs = match input {
 756             None => None,
 757             Some(input) => {
 758                 let result = parse_crate_attrs(sess, input);
 759                 match result {
 760                     Ok(attrs) => Some(attrs),
 761                     Err(mut parse_error) => {
 762                         parse_error.emit();
 763                         return Compilation::Stop;
 764                     }
 765                 }
 766             }
 767         };
 768         for req in &sess.opts.prints {
 769             match *req {
 770                 TargetList => {
 771                     let mut targets = rustc_back::target::get_targets().collect::<Vec<String>>();
 772                     targets.sort();
 773                     println!("{}", targets.join("\n"));
 774                 },
 775                 Sysroot => println!("{}", sess.sysroot().display()),
 776                 TargetSpec => println!("{}", sess.target.target.to_json().pretty()),
 777                 FileNames | CrateName => {
 778                     let input = match input {
 779                         Some(input) => input,
 780                         None => early_error(ErrorOutputType::default(), "no input file provided"),
 781                     };
 782                     let attrs = attrs.as_ref().unwrap();
 783                     let t_outputs = driver::build_output_filenames(input, odir, ofile, attrs, sess);
 784                     let id = rustc_trans_utils::link::find_crate_name(Some(sess), attrs, input);
 785                     if *req == PrintRequest::CrateName {
 786                         println!("{}", id);
 787                         continue;
 788                     }
 789                     let crate_types = driver::collect_crate_types(sess, attrs);
 790                     for &style in &crate_types {
 791                         let fname = rustc_trans_utils::link::filename_for_input(
 792                             sess,
 793                             style,
 794                             &id,
 795                             &t_outputs
 796                         );
 797                         println!("{}",
 798                                  fname.file_name()
 799                                       .unwrap()
 800                                       .to_string_lossy());
 801                     }
 802                 }
 803                 Cfg => {
 804                     let allow_unstable_cfg = UnstableFeatures::from_environment()
 805                         .is_nightly_build();
 806
 807                     let mut cfgs = Vec::new();
 808                     for &(name, ref value) in sess.parse_sess.config.iter() {
 809                         let gated_cfg = GatedCfg::gate(&ast::MetaItem {
 810                             name,
 811                             node: ast::MetaItemKind::Word,
 812                             span: DUMMY_SP,
 813                         });
 814
 815                         // Note that crt-static is a specially recognized cfg
 816                         // directive that's printed out here as part of
 817                         // rust-lang/rust#37406, but in general the
 818                         // `target_feature` cfg is gated under
 819                         // rust-lang/rust#29717. For now this is just
 820                         // specifically allowing the crt-static cfg and that's
 821                         // it, this is intended to get into Cargo and then go
 822                         // through to build scripts.
 823                         let value = value.as_ref().map(|s| s.as_str());
 824                         let value = value.as_ref().map(|s| s.as_ref());
 825                         if name != "target_feature" || value != Some("crt-static") {
 826                             if !allow_unstable_cfg && gated_cfg.is_some() {
 827                                 continue;
 828                             }
 829                         }
 830
 831                         cfgs.push(if let Some(value) = value {
 832                             format!("{}=\"{}\"", name, value)
 833                         } else {
 834                             format!("{}", name)
 835                         });
 836                     }
 837
 838                     cfgs.sort();
 839                     for cfg in cfgs {
 840                         println!("{}", cfg);
 841                     }
 842                 }
 843                 RelocationModels | CodeModels | TlsModels | TargetCPUs | TargetFeatures => {
 844                     trans.print(*req, sess);
 845                 }
 846                 // Any output here interferes with Cargo's parsing of other printed output
 847                 PrintRequest::NativeStaticLibs => {}
 848             }
 849         }
 850         return Compilation::Stop;
 851     }
 852 }
 853
 854 /// Returns a version string such as "0.12.0-dev".
 855 fn release_str() -> Option<&'static str> {
 856     option_env!("CFG_RELEASE")
 857 }
 858
 859 /// Returns the full SHA1 hash of HEAD of the Git repo from which rustc was built.
 860 fn commit_hash_str() -> Option<&'static str> {
 861     option_env!("CFG_VER_HASH")
 862 }
 863
 864 /// Returns the "commit date" of HEAD of the Git repo from which rustc was built as a static string.
 865 fn commit_date_str() -> Option<&'static str> {
 866     option_env!("CFG_VER_DATE")
 867 }
 868
 869 /// Prints version information
 870 pub fn version(binary: &str, matches: &getopts::Matches) {
 871     let verbose = matches.opt_present("verbose");
 872
 873     println!("{} {}",
 874              binary,
 875              option_env!("CFG_VERSION").unwrap_or("unknown version"));
 876     if verbose {
 877         fn unw(x: Option<&str>) -> &str {
 878             x.unwrap_or("unknown")
 879         }
 880         println!("binary: {}", binary);
 881         println!("commit-hash: {}", unw(commit_hash_str()));
 882         println!("commit-date: {}", unw(commit_date_str()));
 883         println!("host: {}", config::host_triple());
 884         println!("release: {}", unw(release_str()));
 885         rustc_trans::print_version();
 886     }
 887 }
 888
 889 fn usage(verbose: bool, include_unstable_options: bool) {
 890     let groups = if verbose {
 891         config::rustc_optgroups()
 892     } else {
 893         config::rustc_short_optgroups()
 894     };
 895     let mut options = getopts::Options::new();
 896     for option in groups.iter().filter(|x| include_unstable_options || x.is_stable()) {
 897         (option.apply)(&mut options);
 898     }
 899     let message = format!("Usage: rustc [OPTIONS] INPUT");
 900     let nightly_help = if nightly_options::is_nightly_build() {
 901         "\n    -Z help             Print internal options for debugging rustc"
 902     } else {
 903         ""
 904     };
 905     let verbose_help = if verbose {
 906         ""
 907     } else {
 908         "\n    --help -v           Print the full set of options rustc accepts"
 909     };
 910     println!("{}\nAdditional help:
 911     -C help             Print codegen options
 912     -W help             \
 913               Print 'lint' options and default settings{}{}\n",
 914              options.usage(&message),
 915              nightly_help,
 916              verbose_help);
 917 }
 918
 919 fn describe_lints(lint_store: &lint::LintStore, loaded_plugins: bool) {
 920     println!("
 921 Available lint options:
 922     -W <foo>           Warn about <foo>
 923     -A <foo>           \
 924               Allow <foo>
 925     -D <foo>           Deny <foo>
 926     -F <foo>           Forbid <foo> \
 927               (deny <foo> and all attempts to override)
 928
 929 ");
 930
 931     fn sort_lints(lints: Vec<(&'static Lint, bool)>) -> Vec<&'static Lint> {
 932         let mut lints: Vec<_> = lints.into_iter().map(|(x, _)| x).collect();
 933         lints.sort_by(|x: &&Lint, y: &&Lint| {
 934             match x.default_level.cmp(&y.default_level) {
 935                 // The sort doesn't case-fold but it's doubtful we care.
 936                 Equal => x.name.cmp(y.name),
 937                 r => r,
 938             }
 939         });
 940         lints
 941     }
 942
 943     fn sort_lint_groups(lints: Vec<(&'static str, Vec<lint::LintId>, bool)>)
 944                         -> Vec<(&'static str, Vec<lint::LintId>)> {
 945         let mut lints: Vec<_> = lints.into_iter().map(|(x, y, _)| (x, y)).collect();
 946         lints.sort_by(|&(x, _): &(&'static str, Vec<lint::LintId>),
 947                        &(y, _): &(&'static str, Vec<lint::LintId>)| {
 948             x.cmp(y)
 949         });
 950         lints
 951     }
 952
 953     let (plugin, builtin): (Vec<_>, _) = lint_store.get_lints()
 954                                                    .iter()
 955                                                    .cloned()
 956                                                    .partition(|&(_, p)| p);
 957     let plugin = sort_lints(plugin);
 958     let builtin = sort_lints(builtin);
 959
 960     let (plugin_groups, builtin_groups): (Vec<_>, _) = lint_store.get_lint_groups()
 961                                                                  .iter()
 962                                                                  .cloned()
 963                                                                  .partition(|&(.., p)| p);
 964     let plugin_groups = sort_lint_groups(plugin_groups);
 965     let builtin_groups = sort_lint_groups(builtin_groups);
 966
 967     let max_name_len = plugin.iter()
 968                              .chain(&builtin)
 969                              .map(|&s| s.name.chars().count())
 970                              .max()
 971                              .unwrap_or(0);
 972     let padded = |x: &str| {
 973         let mut s = repeat(" ")
 974                         .take(max_name_len - x.chars().count())
 975                         .collect::<String>();
 976         s.push_str(x);
 977         s
 978     };
 979
 980     println!("Lint checks provided by rustc:\n");
 981     println!("    {}  {:7.7}  {}", padded("name"), "default", "meaning");
 982     println!("    {}  {:7.7}  {}", padded("----"), "-------", "-------");
 983
 984     let print_lints = |lints: Vec<&Lint>| {
 985         for lint in lints {
 986             let name = lint.name_lower().replace("_", "-");
 987             println!("    {}  {:7.7}  {}",
 988                      padded(&name),
 989                      lint.default_level.as_str(),
 990                      lint.desc);
 991         }
 992         println!("\n");
 993     };
 994
 995     print_lints(builtin);
 996
 997
 998
 999     let max_name_len = max("warnings".len(),
1000                            plugin_groups.iter()
1001                                         .chain(&builtin_groups)
1002                                         .map(|&(s, _)| s.chars().count())
1003                                         .max()
1004                                         .unwrap_or(0));
1005
1006     let padded = |x: &str| {
1007         let mut s = repeat(" ")
1008                         .take(max_name_len - x.chars().count())
1009                         .collect::<String>();
1010         s.push_str(x);
1011         s
1012     };
1013
1014     println!("Lint groups provided by rustc:\n");
1015     println!("    {}  {}", padded("name"), "sub-lints");
1016     println!("    {}  {}", padded("----"), "---------");
1017     println!("    {}  {}", padded("warnings"), "all lints that are set to issue warnings");
1018
1019     let print_lint_groups = |lints: Vec<(&'static str, Vec<lint::LintId>)>| {
1020         for (name, to) in lints {
1021             let name = name.to_lowercase().replace("_", "-");
1022             let desc = to.into_iter()
1023                          .map(|x| x.to_string().replace("_", "-"))
1024                          .collect::<Vec<String>>()
1025                          .join(", ");
1026             println!("    {}  {}", padded(&name), desc);
1027         }
1028         println!("\n");
1029     };
1030
1031     print_lint_groups(builtin_groups);
1032
1033     match (loaded_plugins, plugin.len(), plugin_groups.len()) {
1034         (false, 0, _) | (false, _, 0) => {
1035             println!("Compiler plugins can provide additional lints and lint groups. To see a \
1036                       listing of these, re-run `rustc -W help` with a crate filename.");
1037         }
1038         (false, ..) => panic!("didn't load lint plugins but got them anyway!"),
1039         (true, 0, 0) => println!("This crate does not load any lint plugins or lint groups."),
1040         (true, l, g) => {
1041             if l > 0 {
1042                 println!("Lint checks provided by plugins loaded by this crate:\n");
1043                 print_lints(plugin);
1044             }
1045             if g > 0 {
1046                 println!("Lint groups provided by plugins loaded by this crate:\n");
1047                 print_lint_groups(plugin_groups);
1048             }
1049         }
1050     }
1051 }
1052
1053 fn describe_debug_flags() {
1054     println!("\nAvailable debug options:\n");
1055     print_flag_list("-Z", config::DB_OPTIONS);
1056 }
1057
1058 fn describe_codegen_flags() {
1059     println!("\nAvailable codegen options:\n");
1060     print_flag_list("-C", config::CG_OPTIONS);
1061 }
1062
1063 fn print_flag_list<T>(cmdline_opt: &str,
1064                       flag_list: &[(&'static str, T, Option<&'static str>, &'static str)]) {
1065     let max_len = flag_list.iter()
1066                            .map(|&(name, _, opt_type_desc, _)| {
1067                                let extra_len = match opt_type_desc {
1068                                    Some(..) => 4,
1069                                    None => 0,
1070                                };
1071                                name.chars().count() + extra_len
1072                            })
1073                            .max()
1074                            .unwrap_or(0);
1075
1076     for &(name, _, opt_type_desc, desc) in flag_list {
1077         let (width, extra) = match opt_type_desc {
1078             Some(..) => (max_len - 4, "=val"),
1079             None => (max_len, ""),
1080         };
1081         println!("    {} {:>width$}{} -- {}",
1082                  cmdline_opt,
1083                  name.replace("_", "-"),
1084                  extra,
1085                  desc,
1086                  width = width);
1087     }
1088 }
1089
1090 /// Process command line options. Emits messages as appropriate. If compilation
1091 /// should continue, returns a getopts::Matches object parsed from args,
1092 /// otherwise returns None.
1093 ///
1094 /// The compiler's handling of options is a little complicated as it ties into
1095 /// our stability story, and it's even *more* complicated by historical
1096 /// accidents. The current intention of each compiler option is to have one of
1097 /// three modes:
1098 ///
1099 /// 1. An option is stable and can be used everywhere.
1100 /// 2. An option is unstable, but was historically allowed on the stable
1101 ///    channel.
1102 /// 3. An option is unstable, and can only be used on nightly.
1103 ///
1104 /// Like unstable library and language features, however, unstable options have
1105 /// always required a form of "opt in" to indicate that you're using them. This
1106 /// provides the easy ability to scan a code base to check to see if anything
1107 /// unstable is being used. Currently, this "opt in" is the `-Z` "zed" flag.
1108 ///
1109 /// All options behind `-Z` are considered unstable by default. Other top-level
1110 /// options can also be considered unstable, and they were unlocked through the
1111 /// `-Z unstable-options` flag. Note that `-Z` remains to be the root of
1112 /// instability in both cases, though.
1113 ///
1114 /// So with all that in mind, the comments below have some more detail about the
1115 /// contortions done here to get things to work out correctly.
1116 pub fn handle_options(args: &[String]) -> Option<getopts::Matches> {
1117     // Throw away the first argument, the name of the binary
1118     let args = &args[1..];
1119
1120     if args.is_empty() {
1121         // user did not write `-v` nor `-Z unstable-options`, so do not
1122         // include that extra information.
1123         usage(false, false);
1124         return None;
1125     }
1126
1127     // Parse with *all* options defined in the compiler, we don't worry about
1128     // option stability here we just want to parse as much as possible.
1129     let mut options = getopts::Options::new();
1130     for option in config::rustc_optgroups() {
1131         (option.apply)(&mut options);
1132     }
1133     let matches = match options.parse(args) {
1134         Ok(m) => m,
1135         Err(f) => early_error(ErrorOutputType::default(), &f.to_string()),
1136     };
1137
1138     // For all options we just parsed, we check a few aspects:
1139     //
1140     // * If the option is stable, we're all good
1141     // * If the option wasn't passed, we're all good
1142     // * If `-Z unstable-options` wasn't passed (and we're not a -Z option
1143     //   ourselves), then we require the `-Z unstable-options` flag to unlock
1144     //   this option that was passed.
1145     // * If we're a nightly compiler, then unstable options are now unlocked, so
1146     //   we're good to go.
1147     // * Otherwise, if we're a truly unstable option then we generate an error
1148     //   (unstable option being used on stable)
1149     // * If we're a historically stable-but-should-be-unstable option then we
1150     //   emit a warning that we're going to turn this into an error soon.
1151     nightly_options::check_nightly_options(&matches, &config::rustc_optgroups());
1152
1153     if matches.opt_present("h") || matches.opt_present("help") {
1154         // Only show unstable options in --help if we *really* accept unstable
1155         // options, which catches the case where we got `-Z unstable-options` on
1156         // the stable channel of Rust which was accidentally allowed
1157         // historically.
1158         usage(matches.opt_present("verbose"),
1159               nightly_options::is_unstable_enabled(&matches));
1160         return None;
1161     }
1162
1163     // Don't handle -W help here, because we might first load plugins.
1164     let r = matches.opt_strs("Z");
1165     if r.iter().any(|x| *x == "help") {
1166         describe_debug_flags();
1167         return None;
1168     }
1169
1170     let cg_flags = matches.opt_strs("C");
1171     if cg_flags.iter().any(|x| *x == "help") {
1172         describe_codegen_flags();
1173         return None;
1174     }
1175
1176     if cg_flags.iter().any(|x| *x == "no-stack-check") {
1177         early_warn(ErrorOutputType::default(),
1178                    "the --no-stack-check flag is deprecated and does nothing");
1179     }
1180
1181     if cg_flags.contains(&"passes=list".to_string()) {
1182         rustc_trans::print_passes();
1183         return None;
1184     }
1185
1186     if matches.opt_present("version") {
1187         version("rustc", &matches);
1188         return None;
1189     }
1190
1191     Some(matches)
1192 }
1193
1194 fn parse_crate_attrs<'a>(sess: &'a Session, input: &Input) -> PResult<'a, Vec<ast::Attribute>> {
1195     match *input {
1196         Input::File(ref ifile) => {
1197             parse::parse_crate_attrs_from_file(ifile, &sess.parse_sess)
1198         }
1199         Input::Str { ref name, ref input } => {
1200             parse::parse_crate_attrs_from_source_str(name.clone(),
1201                                                      input.clone(),
1202                                                      &sess.parse_sess)
1203         }
1204     }
1205 }
1206
1207 /// Runs `f` in a suitable thread for running `rustc`; returns a
1208 /// `Result` with either the return value of `f` or -- if a panic
1209 /// occurs -- the panic value.
1210 pub fn in_rustc_thread<F, R>(f: F) -> Result<R, Box<Any + Send>>
1211     where F: FnOnce() -> R + Send + 'static,
1212           R: Send + 'static,
1213 {
1214     // Temporarily have stack size set to 16MB to deal with nom-using crates failing
1215     const STACK_SIZE: usize = 16 * 1024 * 1024; // 16MB
1216
1217     let mut cfg = thread::Builder::new().name("rustc".to_string());
1218
1219     // FIXME: Hacks on hacks. If the env is trying to override the stack size
1220     // then *don't* set it explicitly.
1221     if env::var_os("RUST_MIN_STACK").is_none() {
1222         cfg = cfg.stack_size(STACK_SIZE);
1223     }
1224
1225     let thread = cfg.spawn(f);
1226     thread.unwrap().join()
1227 }
1228
1229 /// Run a procedure which will detect panics in the compiler and print nicer
1230 /// error messages rather than just failing the test.
1231 ///
1232 /// The diagnostic emitter yielded to the procedure should be used for reporting
1233 /// errors of the compiler.
1234 pub fn monitor<F: FnOnce() + Send + 'static>(f: F) {
1235     struct Sink(Arc<Mutex<Vec<u8>>>);
1236     impl Write for Sink {
1237         fn write(&mut self, data: &[u8]) -> io::Result<usize> {
1238             Write::write(&mut *self.0.lock().unwrap(), data)
1239         }
1240         fn flush(&mut self) -> io::Result<()> {
1241             Ok(())
1242         }
1243     }
1244
1245     let data = Arc::new(Mutex::new(Vec::new()));
1246     let err = Sink(data.clone());
1247
1248     let result = in_rustc_thread(move || {
1249         io::set_panic(Some(box err));
1250         f()
1251     });
1252
1253     if let Err(value) = result {
1254         // Thread panicked without emitting a fatal diagnostic
1255         if !value.is::<errors::FatalError>() {
1256             let emitter =
1257                 Box::new(errors::emitter::EmitterWriter::stderr(errors::ColorConfig::Auto,
1258                                                                 None,
1259                                                                 false));
1260             let handler = errors::Handler::with_emitter(true, false, emitter);
1261
1262             // a .span_bug or .bug call has already printed what
1263             // it wants to print.
1264             if !value.is::<errors::ExplicitBug>() {
1265                 handler.emit(&MultiSpan::new(),
1266                              "unexpected panic",
1267                              errors::Level::Bug);
1268             }
1269
1270             let xs = ["the compiler unexpectedly panicked. this is a bug.".to_string(),
1271                       format!("we would appreciate a bug report: {}", BUG_REPORT_URL),
1272                       format!("rustc {} running on {}",
1273                               option_env!("CFG_VERSION").unwrap_or("unknown_version"),
1274                               config::host_triple())];
1275             for note in &xs {
1276                 handler.emit(&MultiSpan::new(),
1277                              &note,
1278                              errors::Level::Note);
1279             }
1280             if match env::var_os("RUST_BACKTRACE") {
1281                 Some(val) => &val != "0",
1282                 None => false,
1283             } {
1284                 handler.emit(&MultiSpan::new(),
1285                              "run with `RUST_BACKTRACE=1` for a backtrace",
1286                              errors::Level::Note);
1287             }
1288
1289             eprintln!("{}", str::from_utf8(&data.lock().unwrap()).unwrap());
1290         }
1291
1292         exit_on_err();
1293     }
1294 }
1295
1296 fn exit_on_err() -> ! {
1297     // Panic so the process returns a failure code, but don't pollute the
1298     // output with some unnecessary panic messages, we've already
1299     // printed everything that we needed to.
1300     io::set_panic(Some(box io::sink()));
1301     panic!();
1302 }
1303
1304 #[cfg(stage0)]
1305 pub fn diagnostics_registry() -> errors::registry::Registry {
1306     use errors::registry::Registry;
1307
1308     Registry::new(&[])
1309 }
1310
1311 #[cfg(not(stage0))]
1312 pub fn diagnostics_registry() -> errors::registry::Registry {
1313     use errors::registry::Registry;
1314
1315     let mut all_errors = Vec::new();
1316     all_errors.extend_from_slice(&rustc::DIAGNOSTICS);
1317     all_errors.extend_from_slice(&rustc_typeck::DIAGNOSTICS);
1318     all_errors.extend_from_slice(&rustc_resolve::DIAGNOSTICS);
1319     all_errors.extend_from_slice(&rustc_privacy::DIAGNOSTICS);
1320     #[cfg(feature="llvm")]
1321     all_errors.extend_from_slice(&rustc_trans::DIAGNOSTICS);
1322     all_errors.extend_from_slice(&rustc_trans_utils::DIAGNOSTICS);
1323     all_errors.extend_from_slice(&rustc_const_eval::DIAGNOSTICS);
1324     all_errors.extend_from_slice(&rustc_metadata::DIAGNOSTICS);
1325     all_errors.extend_from_slice(&rustc_passes::DIAGNOSTICS);
1326     all_errors.extend_from_slice(&rustc_plugin::DIAGNOSTICS);
1327     all_errors.extend_from_slice(&rustc_mir::DIAGNOSTICS);
1328     all_errors.extend_from_slice(&syntax::DIAGNOSTICS);
1329
1330     Registry::new(&all_errors)
1331 }
1332
1333 pub fn get_args() -> Vec<String> {
1334     env::args_os().enumerate()
1335         .map(|(i, arg)| arg.into_string().unwrap_or_else(|arg| {
1336              early_error(ErrorOutputType::default(),
1337                          &format!("Argument {} is not valid Unicode: {:?}", i, arg))
1338          }))
1339         .collect()
1340 }
1341
1342 pub fn main() {
1343     env_logger::init().unwrap();
1344     let result = run(|| run_compiler(&get_args(),
1345                                      &mut RustcDefaultCalls,
1346                                      None,
1347                                      None));
1348     process::exit(result as i32);
1349 }