src/librustc/session/mod.rs

   1 // Copyright 2012-2013 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 use lint;
  12 use middle::cstore::CrateStore;
  13 use middle::dependency_format;
  14 use session::search_paths::PathKind;
  15 use ty::tls;
  16 use util::nodemap::{NodeMap, FnvHashMap};
  17 use mir::transform as mir_pass;
  18
  19 use syntax::ast::{NodeId, NodeIdAssigner, Name};
  20 use syntax::codemap::{Span, MultiSpan};
  21 use syntax::errors::{self, DiagnosticBuilder};
  22 use syntax::errors::emitter::{Emitter, BasicEmitter, EmitterWriter};
  23 use syntax::errors::json::JsonEmitter;
  24 use syntax::diagnostics;
  25 use syntax::feature_gate;
  26 use syntax::parse;
  27 use syntax::parse::ParseSess;
  28 use syntax::parse::token;
  29 use syntax::{ast, codemap};
  30 use syntax::feature_gate::AttributeType;
  31
  32 use rustc_back::target::Target;
  33
  34 use std::path::{Path, PathBuf};
  35 use std::cell::{Cell, RefCell};
  36 use std::collections::{HashMap, HashSet};
  37 use std::env;
  38 use std::rc::Rc;
  39 use std::fmt;
  40
  41 pub mod config;
  42 pub mod filesearch;
  43 pub mod search_paths;
  44
  45 // Represents the data associated with a compilation
  46 // session for a single crate.
  47 pub struct Session {
  48     pub target: config::Config,
  49     pub host: Target,
  50     pub opts: config::Options,
  51     pub cstore: Rc<for<'a> CrateStore<'a>>,
  52     pub parse_sess: ParseSess,
  53     // For a library crate, this is always none
  54     pub entry_fn: RefCell<Option<(NodeId, Span)>>,
  55     pub entry_type: Cell<Option<config::EntryFnType>>,
  56     pub plugin_registrar_fn: Cell<Option<ast::NodeId>>,
  57     pub default_sysroot: Option<PathBuf>,
  58     // The name of the root source file of the crate, in the local file system.
  59     // The path is always expected to be absolute. `None` means that there is no
  60     // source file.
  61     pub local_crate_source_file: Option<PathBuf>,
  62     pub working_dir: PathBuf,
  63     pub lint_store: RefCell<lint::LintStore>,
  64     pub lints: RefCell<NodeMap<Vec<(lint::LintId, Span, String)>>>,
  65     pub plugin_llvm_passes: RefCell<Vec<String>>,
  66     pub mir_passes: RefCell<mir_pass::Passes>,
  67     pub plugin_attributes: RefCell<Vec<(String, AttributeType)>>,
  68     pub crate_types: RefCell<Vec<config::CrateType>>,
  69     pub dependency_formats: RefCell<dependency_format::Dependencies>,
  70     // The crate_disambiguator is constructed out of all the `-C metadata`
  71     // arguments passed to the compiler. Its value together with the crate-name
  72     // forms a unique global identifier for the crate. It is used to allow
  73     // multiple crates with the same name to coexist. See the
  74     // trans::back::symbol_names module for more information.
  75     pub crate_disambiguator: Cell<ast::Name>,
  76     pub features: RefCell<feature_gate::Features>,
  77
  78     /// The maximum recursion limit for potentially infinitely recursive
  79     /// operations such as auto-dereference and monomorphization.
  80     pub recursion_limit: Cell<usize>,
  81
  82     /// The metadata::creader module may inject an allocator dependency if it
  83     /// didn't already find one, and this tracks what was injected.
  84     pub injected_allocator: Cell<Option<ast::CrateNum>>,
  85
  86     /// Names of all bang-style macros and syntax extensions
  87     /// available in this crate
  88     pub available_macros: RefCell<HashSet<Name>>,
  89
  90     /// Map from imported macro spans (which consist of
  91     /// the localized span for the macro body) to the
  92     /// macro name and defintion span in the source crate.
  93     pub imported_macro_spans: RefCell<HashMap<Span, (String, Span)>>,
  94
  95     next_node_id: Cell<ast::NodeId>,
  96 }
  97
  98 impl Session {
  99     pub fn struct_span_warn<'a, S: Into<MultiSpan>>(&'a self,
 100                                                     sp: S,
 101                                                     msg: &str)
 102                                                     -> DiagnosticBuilder<'a>  {
 103         self.diagnostic().struct_span_warn(sp, msg)
 104     }
 105     pub fn struct_span_warn_with_code<'a, S: Into<MultiSpan>>(&'a self,
 106                                                               sp: S,
 107                                                               msg: &str,
 108                                                               code: &str)
 109                                                               -> DiagnosticBuilder<'a>  {
 110         self.diagnostic().struct_span_warn_with_code(sp, msg, code)
 111     }
 112     pub fn struct_warn<'a>(&'a self, msg: &str) -> DiagnosticBuilder<'a>  {
 113         self.diagnostic().struct_warn(msg)
 114     }
 115     pub fn struct_span_err<'a, S: Into<MultiSpan>>(&'a self,
 116                                                    sp: S,
 117                                                    msg: &str)
 118                                                    -> DiagnosticBuilder<'a>  {
 119         match split_msg_into_multilines(msg) {
 120             Some(ref msg) => self.diagnostic().struct_span_err(sp, msg),
 121             None => self.diagnostic().struct_span_err(sp, msg),
 122         }
 123     }
 124     pub fn struct_span_err_with_code<'a, S: Into<MultiSpan>>(&'a self,
 125                                                              sp: S,
 126                                                              msg: &str,
 127                                                              code: &str)
 128                                                              -> DiagnosticBuilder<'a>  {
 129         match split_msg_into_multilines(msg) {
 130             Some(ref msg) => self.diagnostic().struct_span_err_with_code(sp, msg, code),
 131             None => self.diagnostic().struct_span_err_with_code(sp, msg, code),
 132         }
 133     }
 134     pub fn struct_err<'a>(&'a self, msg: &str) -> DiagnosticBuilder<'a>  {
 135         self.diagnostic().struct_err(msg)
 136     }
 137     pub fn struct_span_fatal<'a, S: Into<MultiSpan>>(&'a self,
 138                                                      sp: S,
 139                                                      msg: &str)
 140                                                      -> DiagnosticBuilder<'a>  {
 141         self.diagnostic().struct_span_fatal(sp, msg)
 142     }
 143     pub fn struct_span_fatal_with_code<'a, S: Into<MultiSpan>>(&'a self,
 144                                                                sp: S,
 145                                                                msg: &str,
 146                                                                code: &str)
 147                                                                -> DiagnosticBuilder<'a>  {
 148         self.diagnostic().struct_span_fatal_with_code(sp, msg, code)
 149     }
 150     pub fn struct_fatal<'a>(&'a self, msg: &str) -> DiagnosticBuilder<'a>  {
 151         self.diagnostic().struct_fatal(msg)
 152     }
 153
 154     pub fn span_fatal<S: Into<MultiSpan>>(&self, sp: S, msg: &str) -> ! {
 155         panic!(self.diagnostic().span_fatal(sp, msg))
 156     }
 157     pub fn span_fatal_with_code<S: Into<MultiSpan>>(&self, sp: S, msg: &str, code: &str) -> ! {
 158         panic!(self.diagnostic().span_fatal_with_code(sp, msg, code))
 159     }
 160     pub fn fatal(&self, msg: &str) -> ! {
 161         panic!(self.diagnostic().fatal(msg))
 162     }
 163     pub fn span_err_or_warn<S: Into<MultiSpan>>(&self, is_warning: bool, sp: S, msg: &str) {
 164         if is_warning {
 165             self.span_warn(sp, msg);
 166         } else {
 167             self.span_err(sp, msg);
 168         }
 169     }
 170     pub fn span_err<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
 171         match split_msg_into_multilines(msg) {
 172             Some(msg) => self.diagnostic().span_err(sp, &msg),
 173             None => self.diagnostic().span_err(sp, msg)
 174         }
 175     }
 176     pub fn span_err_with_code<S: Into<MultiSpan>>(&self, sp: S, msg: &str, code: &str) {
 177         match split_msg_into_multilines(msg) {
 178             Some(msg) => self.diagnostic().span_err_with_code(sp, &msg, code),
 179             None => self.diagnostic().span_err_with_code(sp, msg, code)
 180         }
 181     }
 182     pub fn err(&self, msg: &str) {
 183         self.diagnostic().err(msg)
 184     }
 185     pub fn err_count(&self) -> usize {
 186         self.diagnostic().err_count()
 187     }
 188     pub fn has_errors(&self) -> bool {
 189         self.diagnostic().has_errors()
 190     }
 191     pub fn abort_if_errors(&self) {
 192         self.diagnostic().abort_if_errors();
 193     }
 194     pub fn track_errors<F, T>(&self, f: F) -> Result<T, usize>
 195         where F: FnOnce() -> T
 196     {
 197         let old_count = self.err_count();
 198         let result = f();
 199         let errors = self.err_count() - old_count;
 200         if errors == 0 {
 201             Ok(result)
 202         } else {
 203             Err(errors)
 204         }
 205     }
 206     pub fn span_warn<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
 207         self.diagnostic().span_warn(sp, msg)
 208     }
 209     pub fn span_warn_with_code<S: Into<MultiSpan>>(&self, sp: S, msg: &str, code: &str) {
 210         self.diagnostic().span_warn_with_code(sp, msg, code)
 211     }
 212     pub fn warn(&self, msg: &str) {
 213         self.diagnostic().warn(msg)
 214     }
 215     pub fn opt_span_warn<S: Into<MultiSpan>>(&self, opt_sp: Option<S>, msg: &str) {
 216         match opt_sp {
 217             Some(sp) => self.span_warn(sp, msg),
 218             None => self.warn(msg),
 219         }
 220     }
 221     /// Delay a span_bug() call until abort_if_errors()
 222     pub fn delay_span_bug<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
 223         self.diagnostic().delay_span_bug(sp, msg)
 224     }
 225     pub fn note_without_error(&self, msg: &str) {
 226         self.diagnostic().note_without_error(msg)
 227     }
 228     pub fn span_note_without_error<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
 229         self.diagnostic().span_note_without_error(sp, msg)
 230     }
 231     pub fn span_unimpl<S: Into<MultiSpan>>(&self, sp: S, msg: &str) -> ! {
 232         self.diagnostic().span_unimpl(sp, msg)
 233     }
 234     pub fn unimpl(&self, msg: &str) -> ! {
 235         self.diagnostic().unimpl(msg)
 236     }
 237     pub fn add_lint(&self,
 238                     lint: &'static lint::Lint,
 239                     id: ast::NodeId,
 240                     sp: Span,
 241                     msg: String) {
 242         let lint_id = lint::LintId::of(lint);
 243         let mut lints = self.lints.borrow_mut();
 244         match lints.get_mut(&id) {
 245             Some(arr) => {
 246                 let tuple = (lint_id, sp, msg);
 247                 if !arr.contains(&tuple) {
 248                     arr.push(tuple);
 249                 }
 250                 return;
 251             }
 252             None => {}
 253         }
 254         lints.insert(id, vec!((lint_id, sp, msg)));
 255     }
 256     pub fn reserve_node_ids(&self, count: ast::NodeId) -> ast::NodeId {
 257         let id = self.next_node_id.get();
 258
 259         match id.checked_add(count) {
 260             Some(next) => self.next_node_id.set(next),
 261             None => bug!("Input too large, ran out of node ids!")
 262         }
 263
 264         id
 265     }
 266     pub fn diagnostic<'a>(&'a self) -> &'a errors::Handler {
 267         &self.parse_sess.span_diagnostic
 268     }
 269     pub fn codemap<'a>(&'a self) -> &'a codemap::CodeMap {
 270         self.parse_sess.codemap()
 271     }
 272     pub fn verbose(&self) -> bool { self.opts.debugging_opts.verbose }
 273     pub fn time_passes(&self) -> bool { self.opts.debugging_opts.time_passes }
 274     pub fn count_llvm_insns(&self) -> bool {
 275         self.opts.debugging_opts.count_llvm_insns
 276     }
 277     pub fn count_type_sizes(&self) -> bool {
 278         self.opts.debugging_opts.count_type_sizes
 279     }
 280     pub fn time_llvm_passes(&self) -> bool {
 281         self.opts.debugging_opts.time_llvm_passes
 282     }
 283     pub fn trans_stats(&self) -> bool { self.opts.debugging_opts.trans_stats }
 284     pub fn meta_stats(&self) -> bool { self.opts.debugging_opts.meta_stats }
 285     pub fn asm_comments(&self) -> bool { self.opts.debugging_opts.asm_comments }
 286     pub fn no_verify(&self) -> bool { self.opts.debugging_opts.no_verify }
 287     pub fn borrowck_stats(&self) -> bool { self.opts.debugging_opts.borrowck_stats }
 288     pub fn print_llvm_passes(&self) -> bool {
 289         self.opts.debugging_opts.print_llvm_passes
 290     }
 291     pub fn lto(&self) -> bool {
 292         self.opts.cg.lto
 293     }
 294     pub fn no_landing_pads(&self) -> bool {
 295         self.opts.debugging_opts.no_landing_pads
 296     }
 297     pub fn unstable_options(&self) -> bool {
 298         self.opts.debugging_opts.unstable_options
 299     }
 300     pub fn print_enum_sizes(&self) -> bool {
 301         self.opts.debugging_opts.print_enum_sizes
 302     }
 303     pub fn nonzeroing_move_hints(&self) -> bool {
 304         self.opts.debugging_opts.enable_nonzeroing_move_hints
 305     }
 306     pub fn sysroot<'a>(&'a self) -> &'a Path {
 307         match self.opts.maybe_sysroot {
 308             Some (ref sysroot) => sysroot,
 309             None => self.default_sysroot.as_ref()
 310                         .expect("missing sysroot and default_sysroot in Session")
 311         }
 312     }
 313     pub fn target_filesearch(&self, kind: PathKind) -> filesearch::FileSearch {
 314         filesearch::FileSearch::new(self.sysroot(),
 315                                     &self.opts.target_triple,
 316                                     &self.opts.search_paths,
 317                                     kind)
 318     }
 319     pub fn host_filesearch(&self, kind: PathKind) -> filesearch::FileSearch {
 320         filesearch::FileSearch::new(
 321             self.sysroot(),
 322             config::host_triple(),
 323             &self.opts.search_paths,
 324             kind)
 325     }
 326 }
 327
 328 impl NodeIdAssigner for Session {
 329     fn next_node_id(&self) -> NodeId {
 330         self.reserve_node_ids(1)
 331     }
 332
 333     fn peek_node_id(&self) -> NodeId {
 334         self.next_node_id.get().checked_add(1).unwrap()
 335     }
 336
 337     fn diagnostic(&self) -> &errors::Handler {
 338         self.diagnostic()
 339     }
 340 }
 341
 342 fn split_msg_into_multilines(msg: &str) -> Option<String> {
 343     // Conditions for enabling multi-line errors:
 344     if !msg.contains("mismatched types") &&
 345         !msg.contains("type mismatch resolving") &&
 346         !msg.contains("if and else have incompatible types") &&
 347         !msg.contains("if may be missing an else clause") &&
 348         !msg.contains("match arms have incompatible types") &&
 349         !msg.contains("structure constructor specifies a structure of type") &&
 350         !msg.contains("has an incompatible type for trait") {
 351             return None
 352     }
 353     let first = msg.match_indices("expected").filter(|s| {
 354         let last = msg[..s.0].chars().rev().next();
 355         last == Some(' ') || last == Some('(')
 356     }).map(|(a, b)| (a - 1, a + b.len()));
 357     let second = msg.match_indices("found").filter(|s| {
 358         msg[..s.0].chars().rev().next() == Some(' ')
 359     }).map(|(a, b)| (a - 1, a + b.len()));
 360
 361     let mut new_msg = String::new();
 362     let mut head = 0;
 363
 364     // Insert `\n` before expected and found.
 365     for (pos1, pos2) in first.zip(second) {
 366         new_msg = new_msg +
 367         // A `(` may be preceded by a space and it should be trimmed
 368                   msg[head..pos1.0].trim_right() + // prefix
 369                   "\n" +                           // insert before first
 370                   &msg[pos1.0..pos1.1] +           // insert what first matched
 371                   &msg[pos1.1..pos2.0] +           // between matches
 372                   "\n   " +                        // insert before second
 373         //           123
 374         // `expected` is 3 char longer than `found`. To align the types,
 375         // `found` gets 3 spaces prepended.
 376                   &msg[pos2.0..pos2.1];            // insert what second matched
 377
 378         head = pos2.1;
 379     }
 380
 381     let mut tail = &msg[head..];
 382     let third = tail.find("(values differ")
 383                    .or(tail.find("(lifetime"))
 384                    .or(tail.find("(cyclic type of infinite size"));
 385     // Insert `\n` before any remaining messages which match.
 386     if let Some(pos) = third {
 387         // The end of the message may just be wrapped in `()` without
 388         // `expected`/`found`.  Push this also to a new line and add the
 389         // final tail after.
 390         new_msg = new_msg +
 391         // `(` is usually preceded by a space and should be trimmed.
 392                   tail[..pos].trim_right() + // prefix
 393                   "\n" +                     // insert before paren
 394                   &tail[pos..];              // append the tail
 395
 396         tail = "";
 397     }
 398
 399     new_msg.push_str(tail);
 400     return Some(new_msg);
 401 }
 402
 403 pub fn build_session(sopts: config::Options,
 404                      local_crate_source_file: Option<PathBuf>,
 405                      registry: diagnostics::registry::Registry,
 406                      cstore: Rc<for<'a> CrateStore<'a>>)
 407                      -> Session {
 408     // FIXME: This is not general enough to make the warning lint completely override
 409     // normal diagnostic warnings, since the warning lint can also be denied and changed
 410     // later via the source code.
 411     let can_print_warnings = sopts.lint_opts
 412         .iter()
 413         .filter(|&&(ref key, _)| *key == "warnings")
 414         .map(|&(_, ref level)| *level != lint::Allow)
 415         .last()
 416         .unwrap_or(true);
 417     let treat_err_as_bug = sopts.treat_err_as_bug;
 418
 419     let codemap = Rc::new(codemap::CodeMap::new());
 420     let emitter: Box<Emitter> = match sopts.error_format {
 421         config::ErrorOutputType::HumanReadable(color_config) => {
 422             Box::new(EmitterWriter::stderr(color_config, Some(registry), codemap.clone()))
 423         }
 424         config::ErrorOutputType::Json => {
 425             Box::new(JsonEmitter::stderr(Some(registry), codemap.clone()))
 426         }
 427     };
 428
 429     let diagnostic_handler =
 430         errors::Handler::with_emitter(can_print_warnings,
 431                                       treat_err_as_bug,
 432                                       emitter);
 433
 434     build_session_(sopts, local_crate_source_file, diagnostic_handler, codemap, cstore)
 435 }
 436
 437 pub fn build_session_(sopts: config::Options,
 438                       local_crate_source_file: Option<PathBuf>,
 439                       span_diagnostic: errors::Handler,
 440                       codemap: Rc<codemap::CodeMap>,
 441                       cstore: Rc<for<'a> CrateStore<'a>>)
 442                       -> Session {
 443     let host = match Target::search(config::host_triple()) {
 444         Ok(t) => t,
 445         Err(e) => {
 446             panic!(span_diagnostic.fatal(&format!("Error loading host specification: {}", e)));
 447     }
 448     };
 449     let target_cfg = config::build_target_config(&sopts, &span_diagnostic);
 450     let p_s = parse::ParseSess::with_span_handler(span_diagnostic, codemap);
 451     let default_sysroot = match sopts.maybe_sysroot {
 452         Some(_) => None,
 453         None => Some(filesearch::get_or_default_sysroot())
 454     };
 455
 456     // Make the path absolute, if necessary
 457     let local_crate_source_file = local_crate_source_file.map(|path|
 458         if path.is_absolute() {
 459             path.clone()
 460         } else {
 461             env::current_dir().unwrap().join(&path)
 462         }
 463     );
 464
 465     let sess = Session {
 466         target: target_cfg,
 467         host: host,
 468         opts: sopts,
 469         cstore: cstore,
 470         parse_sess: p_s,
 471         // For a library crate, this is always none
 472         entry_fn: RefCell::new(None),
 473         entry_type: Cell::new(None),
 474         plugin_registrar_fn: Cell::new(None),
 475         default_sysroot: default_sysroot,
 476         local_crate_source_file: local_crate_source_file,
 477         working_dir: env::current_dir().unwrap(),
 478         lint_store: RefCell::new(lint::LintStore::new()),
 479         lints: RefCell::new(NodeMap()),
 480         plugin_llvm_passes: RefCell::new(Vec::new()),
 481         mir_passes: RefCell::new(mir_pass::Passes::new()),
 482         plugin_attributes: RefCell::new(Vec::new()),
 483         crate_types: RefCell::new(Vec::new()),
 484         dependency_formats: RefCell::new(FnvHashMap()),
 485         crate_disambiguator: Cell::new(token::intern("")),
 486         features: RefCell::new(feature_gate::Features::new()),
 487         recursion_limit: Cell::new(64),
 488         next_node_id: Cell::new(1),
 489         injected_allocator: Cell::new(None),
 490         available_macros: RefCell::new(HashSet::new()),
 491         imported_macro_spans: RefCell::new(HashMap::new()),
 492     };
 493
 494     sess
 495 }
 496
 497 pub fn early_error(output: config::ErrorOutputType, msg: &str) -> ! {
 498     let mut emitter: Box<Emitter> = match output {
 499         config::ErrorOutputType::HumanReadable(color_config) => {
 500             Box::new(BasicEmitter::stderr(color_config))
 501         }
 502         config::ErrorOutputType::Json => Box::new(JsonEmitter::basic()),
 503     };
 504     emitter.emit(None, msg, None, errors::Level::Fatal);
 505     panic!(errors::FatalError);
 506 }
 507
 508 pub fn early_warn(output: config::ErrorOutputType, msg: &str) {
 509     let mut emitter: Box<Emitter> = match output {
 510         config::ErrorOutputType::HumanReadable(color_config) => {
 511             Box::new(BasicEmitter::stderr(color_config))
 512         }
 513         config::ErrorOutputType::Json => Box::new(JsonEmitter::basic()),
 514     };
 515     emitter.emit(None, msg, None, errors::Level::Warning);
 516 }
 517
 518 // Err(0) means compilation was stopped, but no errors were found.
 519 // This would be better as a dedicated enum, but using try! is so convenient.
 520 pub type CompileResult = Result<(), usize>;
 521
 522 pub fn compile_result_from_err_count(err_count: usize) -> CompileResult {
 523     if err_count == 0 {
 524         Ok(())
 525     } else {
 526         Err(err_count)
 527     }
 528 }
 529
 530 #[cold]
 531 #[inline(never)]
 532 pub fn bug_fmt(file: &'static str, line: u32, args: fmt::Arguments) -> ! {
 533     // this wrapper mostly exists so I don't have to write a fully
 534     // qualified path of None::<Span> inside the bug!() macro defintion
 535     opt_span_bug_fmt(file, line, None::<Span>, args);
 536 }
 537
 538 #[cold]
 539 #[inline(never)]
 540 pub fn span_bug_fmt<S: Into<MultiSpan>>(file: &'static str,
 541                                         line: u32,
 542                                         span: S,
 543                                         args: fmt::Arguments) -> ! {
 544     opt_span_bug_fmt(file, line, Some(span), args);
 545 }
 546
 547 fn opt_span_bug_fmt<S: Into<MultiSpan>>(file: &'static str,
 548                                           line: u32,
 549                                           span: Option<S>,
 550                                           args: fmt::Arguments) -> ! {
 551     tls::with_opt(move |tcx| {
 552         let msg = format!("{}:{}: {}", file, line, args);
 553         match (tcx, span) {
 554             (Some(tcx), Some(span)) => tcx.sess.diagnostic().span_bug(span, &msg),
 555             (Some(tcx), None) => tcx.sess.diagnostic().bug(&msg),
 556             (None, _) => panic!(msg)
 557         }
 558     });
 559     unreachable!();
 560 }