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.
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.
11 pub use self::code_stats::{CodeStats, DataTypeKind, FieldInfo};
12 pub use self::code_stats::{SizeKind, TypeSizeInfo, VariantInfo};
14 use hir::def_id::CrateNum;
19 use middle::allocator::AllocatorKind;
20 use middle::dependency_format;
21 use session::search_paths::PathKind;
22 use session::config::{BorrowckMode, DebugInfoLevel, OutputType, Epoch};
24 use util::nodemap::{FxHashMap, FxHashSet};
25 use util::common::{duration_to_secs_str, ErrorReported};
27 use syntax::ast::NodeId;
28 use errors::{self, DiagnosticBuilder, DiagnosticId};
29 use errors::emitter::{Emitter, EmitterWriter};
30 use syntax::json::JsonEmitter;
31 use syntax::feature_gate;
32 use syntax::symbol::Symbol;
34 use syntax::parse::ParseSess;
35 use syntax::{ast, codemap};
36 use syntax::feature_gate::AttributeType;
37 use syntax_pos::{Span, MultiSpan};
39 use rustc_back::{LinkerFlavor, PanicStrategy};
40 use rustc_back::target::Target;
41 use rustc_data_structures::flock;
42 use jobserver::Client;
44 use std::cell::{self, Cell, RefCell};
45 use std::collections::HashMap;
49 use std::path::{Path, PathBuf};
51 use std::sync::{Once, ONCE_INIT};
52 use std::time::Duration;
59 /// Represents the data associated with a compilation
60 /// session for a single crate.
62 pub target: config::Config,
64 pub opts: config::Options,
65 pub parse_sess: ParseSess,
66 /// For a library crate, this is always none
67 pub entry_fn: RefCell<Option<(NodeId, Span)>>,
68 pub entry_type: Cell<Option<config::EntryFnType>>,
69 pub plugin_registrar_fn: Cell<Option<ast::NodeId>>,
70 pub derive_registrar_fn: Cell<Option<ast::NodeId>>,
71 pub default_sysroot: Option<PathBuf>,
72 /// The name of the root source file of the crate, in the local file system.
73 /// `None` means that there is no source file.
74 pub local_crate_source_file: Option<PathBuf>,
75 /// The directory the compiler has been executed in plus a flag indicating
76 /// if the value stored here has been affected by path remapping.
77 pub working_dir: (PathBuf, bool),
78 pub lint_store: RefCell<lint::LintStore>,
79 pub buffered_lints: RefCell<Option<lint::LintBuffer>>,
80 /// Set of (DiagnosticId, Option<Span>, message) tuples tracking
81 /// (sub)diagnostics that have been set once, but should not be set again,
82 /// in order to avoid redundantly verbose output (Issue #24690, #44953).
83 pub one_time_diagnostics: RefCell<FxHashSet<(DiagnosticMessageId, Option<Span>, String)>>,
84 pub plugin_llvm_passes: RefCell<Vec<String>>,
85 pub plugin_attributes: RefCell<Vec<(String, AttributeType)>>,
86 pub crate_types: RefCell<Vec<config::CrateType>>,
87 pub dependency_formats: RefCell<dependency_format::Dependencies>,
88 /// The crate_disambiguator is constructed out of all the `-C metadata`
89 /// arguments passed to the compiler. Its value together with the crate-name
90 /// forms a unique global identifier for the crate. It is used to allow
91 /// multiple crates with the same name to coexist. See the
92 /// trans::back::symbol_names module for more information.
93 pub crate_disambiguator: RefCell<Option<CrateDisambiguator>>,
94 pub features: RefCell<feature_gate::Features>,
96 /// The maximum recursion limit for potentially infinitely recursive
97 /// operations such as auto-dereference and monomorphization.
98 pub recursion_limit: Cell<usize>,
100 /// The maximum length of types during monomorphization.
101 pub type_length_limit: Cell<usize>,
103 /// The metadata::creader module may inject an allocator/panic_runtime
104 /// dependency if it didn't already find one, and this tracks what was
106 pub injected_allocator: Cell<Option<CrateNum>>,
107 pub allocator_kind: Cell<Option<AllocatorKind>>,
108 pub injected_panic_runtime: Cell<Option<CrateNum>>,
110 /// Map from imported macro spans (which consist of
111 /// the localized span for the macro body) to the
112 /// macro name and definition span in the source crate.
113 pub imported_macro_spans: RefCell<HashMap<Span, (String, Span)>>,
115 incr_comp_session: RefCell<IncrCompSession>,
117 /// A cache of attributes ignored by StableHashingContext
118 pub ignored_attr_names: FxHashSet<Symbol>,
120 /// Some measurements that are being gathered during compilation.
121 pub perf_stats: PerfStats,
123 /// Data about code being compiled, gathered during compilation.
124 pub code_stats: RefCell<CodeStats>,
126 next_node_id: Cell<ast::NodeId>,
128 /// If -zfuel=crate=n is specified, Some(crate).
129 optimization_fuel_crate: Option<String>,
130 /// If -zfuel=crate=n is specified, initially set to n. Otherwise 0.
131 optimization_fuel_limit: Cell<u64>,
132 /// We're rejecting all further optimizations.
133 out_of_fuel: Cell<bool>,
135 // The next two are public because the driver needs to read them.
137 /// If -zprint-fuel=crate, Some(crate).
138 pub print_fuel_crate: Option<String>,
139 /// Always set to zero and incremented so that we can print fuel expended by a crate.
140 pub print_fuel: Cell<u64>,
142 /// Loaded up early on in the initialization of this `Session` to avoid
143 /// false positives about a job server in our environment.
144 pub jobserver_from_env: Option<Client>,
146 /// Metadata about the allocators for the current crate being compiled
147 pub has_global_allocator: Cell<bool>,
150 pub struct PerfStats {
151 /// The accumulated time needed for computing the SVH of the crate
152 pub svh_time: Cell<Duration>,
153 /// The accumulated time spent on computing incr. comp. hashes
154 pub incr_comp_hashes_time: Cell<Duration>,
155 /// The number of incr. comp. hash computations performed
156 pub incr_comp_hashes_count: Cell<u64>,
157 /// The number of bytes hashed when computing ICH values
158 pub incr_comp_bytes_hashed: Cell<u64>,
159 /// The accumulated time spent on computing symbol hashes
160 pub symbol_hash_time: Cell<Duration>,
161 /// The accumulated time spent decoding def path tables from metadata
162 pub decode_def_path_tables_time: Cell<Duration>,
165 /// Enum to support dispatch of one-time diagnostics (in Session.diag_once)
166 enum DiagnosticBuilderMethod {
169 SpanSuggestion(String), // suggestion
170 // add more variants as needed to support one-time diagnostics
173 /// Diagnostic message ID—used by `Session.one_time_diagnostics` to avoid
174 /// emitting the same message more than once
175 #[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
176 pub enum DiagnosticMessageId {
177 ErrorId(u16), // EXXXX error code as integer
178 LintId(lint::LintId),
179 StabilityId(u32) // issue number
182 impl From<&'static lint::Lint> for DiagnosticMessageId {
183 fn from(lint: &'static lint::Lint) -> Self {
184 DiagnosticMessageId::LintId(lint::LintId::of(lint))
189 pub fn local_crate_disambiguator(&self) -> CrateDisambiguator {
190 match *self.crate_disambiguator.borrow() {
191 Some(value) => value,
192 None => bug!("accessing disambiguator before initialization"),
195 pub fn struct_span_warn<'a, S: Into<MultiSpan>>(&'a self,
198 -> DiagnosticBuilder<'a> {
199 self.diagnostic().struct_span_warn(sp, msg)
201 pub fn struct_span_warn_with_code<'a, S: Into<MultiSpan>>(&'a self,
205 -> DiagnosticBuilder<'a> {
206 self.diagnostic().struct_span_warn_with_code(sp, msg, code)
208 pub fn struct_warn<'a>(&'a self, msg: &str) -> DiagnosticBuilder<'a> {
209 self.diagnostic().struct_warn(msg)
211 pub fn struct_span_err<'a, S: Into<MultiSpan>>(&'a self,
214 -> DiagnosticBuilder<'a> {
215 self.diagnostic().struct_span_err(sp, msg)
217 pub fn struct_span_err_with_code<'a, S: Into<MultiSpan>>(&'a self,
221 -> DiagnosticBuilder<'a> {
222 self.diagnostic().struct_span_err_with_code(sp, msg, code)
224 // FIXME: This method should be removed (every error should have an associated error code).
225 pub fn struct_err<'a>(&'a self, msg: &str) -> DiagnosticBuilder<'a> {
226 self.diagnostic().struct_err(msg)
228 pub fn struct_err_with_code<'a>(
232 ) -> DiagnosticBuilder<'a> {
233 self.diagnostic().struct_err_with_code(msg, code)
235 pub fn struct_span_fatal<'a, S: Into<MultiSpan>>(&'a self,
238 -> DiagnosticBuilder<'a> {
239 self.diagnostic().struct_span_fatal(sp, msg)
241 pub fn struct_span_fatal_with_code<'a, S: Into<MultiSpan>>(&'a self,
245 -> DiagnosticBuilder<'a> {
246 self.diagnostic().struct_span_fatal_with_code(sp, msg, code)
248 pub fn struct_fatal<'a>(&'a self, msg: &str) -> DiagnosticBuilder<'a> {
249 self.diagnostic().struct_fatal(msg)
252 pub fn span_fatal<S: Into<MultiSpan>>(&self, sp: S, msg: &str) -> ! {
253 self.diagnostic().span_fatal(sp, msg).raise()
255 pub fn span_fatal_with_code<S: Into<MultiSpan>>(
261 self.diagnostic().span_fatal_with_code(sp, msg, code).raise()
263 pub fn fatal(&self, msg: &str) -> ! {
264 self.diagnostic().fatal(msg).raise()
266 pub fn span_err_or_warn<S: Into<MultiSpan>>(&self, is_warning: bool, sp: S, msg: &str) {
268 self.span_warn(sp, msg);
270 self.span_err(sp, msg);
273 pub fn span_err<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
274 self.diagnostic().span_err(sp, msg)
276 pub fn span_err_with_code<S: Into<MultiSpan>>(&self, sp: S, msg: &str, code: DiagnosticId) {
277 self.diagnostic().span_err_with_code(sp, &msg, code)
279 pub fn err(&self, msg: &str) {
280 self.diagnostic().err(msg)
282 pub fn err_count(&self) -> usize {
283 self.diagnostic().err_count()
285 pub fn has_errors(&self) -> bool {
286 self.diagnostic().has_errors()
288 pub fn abort_if_errors(&self) {
289 self.diagnostic().abort_if_errors();
291 pub fn compile_status(&self) -> Result<(), CompileIncomplete> {
292 compile_result_from_err_count(self.err_count())
294 pub fn track_errors<F, T>(&self, f: F) -> Result<T, ErrorReported>
295 where F: FnOnce() -> T
297 let old_count = self.err_count();
299 let errors = self.err_count() - old_count;
306 pub fn span_warn<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
307 self.diagnostic().span_warn(sp, msg)
309 pub fn span_warn_with_code<S: Into<MultiSpan>>(&self, sp: S, msg: &str, code: DiagnosticId) {
310 self.diagnostic().span_warn_with_code(sp, msg, code)
312 pub fn warn(&self, msg: &str) {
313 self.diagnostic().warn(msg)
315 pub fn opt_span_warn<S: Into<MultiSpan>>(&self, opt_sp: Option<S>, msg: &str) {
317 Some(sp) => self.span_warn(sp, msg),
318 None => self.warn(msg),
321 /// Delay a span_bug() call until abort_if_errors()
322 pub fn delay_span_bug<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
323 self.diagnostic().delay_span_bug(sp, msg)
325 pub fn note_without_error(&self, msg: &str) {
326 self.diagnostic().note_without_error(msg)
328 pub fn span_note_without_error<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
329 self.diagnostic().span_note_without_error(sp, msg)
331 pub fn span_unimpl<S: Into<MultiSpan>>(&self, sp: S, msg: &str) -> ! {
332 self.diagnostic().span_unimpl(sp, msg)
334 pub fn unimpl(&self, msg: &str) -> ! {
335 self.diagnostic().unimpl(msg)
338 pub fn buffer_lint<S: Into<MultiSpan>>(&self,
339 lint: &'static lint::Lint,
343 match *self.buffered_lints.borrow_mut() {
344 Some(ref mut buffer) => buffer.add_lint(lint, id, sp.into(), msg),
345 None => bug!("can't buffer lints after HIR lowering"),
349 pub fn reserve_node_ids(&self, count: usize) -> ast::NodeId {
350 let id = self.next_node_id.get();
352 match id.as_usize().checked_add(count) {
354 self.next_node_id.set(ast::NodeId::new(next));
356 None => bug!("Input too large, ran out of node ids!")
361 pub fn next_node_id(&self) -> NodeId {
362 self.reserve_node_ids(1)
364 pub fn diagnostic<'a>(&'a self) -> &'a errors::Handler {
365 &self.parse_sess.span_diagnostic
368 /// Analogous to calling methods on the given `DiagnosticBuilder`, but
369 /// deduplicates on lint ID, span (if any), and message for this `Session`
370 fn diag_once<'a, 'b>(&'a self,
371 diag_builder: &'b mut DiagnosticBuilder<'a>,
372 method: DiagnosticBuilderMethod,
373 msg_id: DiagnosticMessageId,
375 span_maybe: Option<Span>) {
377 let id_span_message = (msg_id, span_maybe, message.to_owned());
378 let fresh = self.one_time_diagnostics.borrow_mut().insert(id_span_message);
381 DiagnosticBuilderMethod::Note => {
382 diag_builder.note(message);
384 DiagnosticBuilderMethod::SpanNote => {
385 let span = span_maybe.expect("span_note needs a span");
386 diag_builder.span_note(span, message);
388 DiagnosticBuilderMethod::SpanSuggestion(suggestion) => {
389 let span = span_maybe.expect("span_suggestion needs a span");
390 diag_builder.span_suggestion(span, message, suggestion);
396 pub fn diag_span_note_once<'a, 'b>(&'a self,
397 diag_builder: &'b mut DiagnosticBuilder<'a>,
398 msg_id: DiagnosticMessageId, span: Span, message: &str) {
399 self.diag_once(diag_builder, DiagnosticBuilderMethod::SpanNote,
400 msg_id, message, Some(span));
403 pub fn diag_note_once<'a, 'b>(&'a self,
404 diag_builder: &'b mut DiagnosticBuilder<'a>,
405 msg_id: DiagnosticMessageId, message: &str) {
406 self.diag_once(diag_builder, DiagnosticBuilderMethod::Note, msg_id, message, None);
409 pub fn diag_span_suggestion_once<'a, 'b>(&'a self,
410 diag_builder: &'b mut DiagnosticBuilder<'a>,
411 msg_id: DiagnosticMessageId,
414 suggestion: String) {
415 self.diag_once(diag_builder, DiagnosticBuilderMethod::SpanSuggestion(suggestion),
416 msg_id, message, Some(span));
419 pub fn codemap<'a>(&'a self) -> &'a codemap::CodeMap {
420 self.parse_sess.codemap()
422 pub fn verbose(&self) -> bool { self.opts.debugging_opts.verbose }
423 pub fn time_passes(&self) -> bool { self.opts.debugging_opts.time_passes }
424 pub fn profile_queries(&self) -> bool {
425 self.opts.debugging_opts.profile_queries ||
426 self.opts.debugging_opts.profile_queries_and_keys
428 pub fn profile_queries_and_keys(&self) -> bool {
429 self.opts.debugging_opts.profile_queries_and_keys
431 pub fn count_llvm_insns(&self) -> bool {
432 self.opts.debugging_opts.count_llvm_insns
434 pub fn time_llvm_passes(&self) -> bool {
435 self.opts.debugging_opts.time_llvm_passes
437 pub fn trans_stats(&self) -> bool { self.opts.debugging_opts.trans_stats }
438 pub fn meta_stats(&self) -> bool { self.opts.debugging_opts.meta_stats }
439 pub fn asm_comments(&self) -> bool { self.opts.debugging_opts.asm_comments }
440 pub fn no_verify(&self) -> bool { self.opts.debugging_opts.no_verify }
441 pub fn borrowck_stats(&self) -> bool { self.opts.debugging_opts.borrowck_stats }
442 pub fn print_llvm_passes(&self) -> bool {
443 self.opts.debugging_opts.print_llvm_passes
446 /// If true, we should use NLL-style region checking instead of
448 pub fn nll(&self) -> bool {
449 self.features.borrow().nll || self.opts.debugging_opts.nll
452 /// If true, we should use the MIR-based borrowck (we may *also* use
453 /// the AST-based borrowck).
454 pub fn use_mir(&self) -> bool {
455 self.borrowck_mode().use_mir()
458 /// If true, we should gather causal information during NLL
459 /// checking. This will eventually be the normal thing, but right
460 /// now it is too unoptimized.
461 pub fn nll_dump_cause(&self) -> bool {
462 self.opts.debugging_opts.nll_dump_cause
465 /// If true, we should enable two-phase borrows checks. This is
466 /// done with either `-Ztwo-phase-borrows` or with
467 /// `#![feature(nll)]`.
468 pub fn two_phase_borrows(&self) -> bool {
469 self.features.borrow().nll || self.opts.debugging_opts.two_phase_borrows
472 /// What mode(s) of borrowck should we run? AST? MIR? both?
473 /// (Also considers the `#![feature(nll)]` setting.)
474 pub fn borrowck_mode(&self) -> BorrowckMode {
475 match self.opts.borrowck_mode {
476 mode @ BorrowckMode::Mir |
477 mode @ BorrowckMode::Compare => mode,
479 mode @ BorrowckMode::Ast => {
490 /// Should we emit EndRegion MIR statements? These are consumed by
491 /// MIR borrowck, but not when NLL is used. They are also consumed
492 /// by the validation stuff.
493 pub fn emit_end_regions(&self) -> bool {
494 // FIXME(#46875) -- we should not emit end regions when NLL is enabled,
495 // but for now we can't stop doing so because it causes false positives
496 self.opts.debugging_opts.emit_end_regions ||
497 self.opts.debugging_opts.mir_emit_validate > 0 ||
501 /// Calculates the flavor of LTO to use for this compilation.
502 pub fn lto(&self) -> config::Lto {
503 // If our target has codegen requirements ignore the command line
504 if self.target.target.options.requires_lto {
505 return config::Lto::Fat
508 // If the user specified something, return that. If they only said `-C
509 // lto` and we've for whatever reason forced off ThinLTO via the CLI,
510 // then ensure we can't use a ThinLTO.
511 match self.opts.cg.lto {
512 config::Lto::No => {}
513 config::Lto::Yes if self.opts.cli_forced_thinlto_off => {
514 return config::Lto::Fat
516 other => return other,
519 // Ok at this point the target doesn't require anything and the user
520 // hasn't asked for anything. Our next decision is whether or not
521 // we enable "auto" ThinLTO where we use multiple codegen units and
522 // then do ThinLTO over those codegen units. The logic below will
523 // either return `No` or `ThinLocal`.
525 // If processing command line options determined that we're incompatible
526 // with ThinLTO (e.g. `-C lto --emit llvm-ir`) then return that option.
527 if self.opts.cli_forced_thinlto_off {
528 return config::Lto::No
531 // If `-Z thinlto` specified process that, but note that this is mostly
532 // a deprecated option now that `-C lto=thin` exists.
533 if let Some(enabled) = self.opts.debugging_opts.thinlto {
535 return config::Lto::ThinLocal
537 return config::Lto::No
541 // If there's only one codegen unit and LTO isn't enabled then there's
542 // no need for ThinLTO so just return false.
543 if self.codegen_units() == 1 {
544 return config::Lto::No
547 // Right now ThinLTO isn't compatible with incremental compilation.
548 if self.opts.incremental.is_some() {
549 return config::Lto::No
552 // Now we're in "defaults" territory. By default we enable ThinLTO for
553 // optimized compiles (anything greater than O0).
554 match self.opts.optimize {
555 config::OptLevel::No => config::Lto::No,
556 _ => config::Lto::ThinLocal,
560 /// Returns the panic strategy for this compile session. If the user explicitly selected one
561 /// using '-C panic', use that, otherwise use the panic strategy defined by the target.
562 pub fn panic_strategy(&self) -> PanicStrategy {
563 self.opts.cg.panic.unwrap_or(self.target.target.options.panic_strategy)
565 pub fn linker_flavor(&self) -> LinkerFlavor {
566 self.opts.debugging_opts.linker_flavor.unwrap_or(self.target.target.linker_flavor)
569 pub fn fewer_names(&self) -> bool {
570 let more_names = self.opts.output_types.contains_key(&OutputType::LlvmAssembly) ||
571 self.opts.output_types.contains_key(&OutputType::Bitcode);
572 self.opts.debugging_opts.fewer_names || !more_names
575 pub fn no_landing_pads(&self) -> bool {
576 self.opts.debugging_opts.no_landing_pads || self.panic_strategy() == PanicStrategy::Abort
578 pub fn unstable_options(&self) -> bool {
579 self.opts.debugging_opts.unstable_options
581 pub fn nonzeroing_move_hints(&self) -> bool {
582 self.opts.debugging_opts.enable_nonzeroing_move_hints
584 pub fn overflow_checks(&self) -> bool {
585 self.opts.cg.overflow_checks
586 .or(self.opts.debugging_opts.force_overflow_checks)
587 .unwrap_or(self.opts.debug_assertions)
590 pub fn crt_static(&self) -> bool {
591 // If the target does not opt in to crt-static support, use its default.
592 if self.target.target.options.crt_static_respected {
593 self.crt_static_feature()
595 self.target.target.options.crt_static_default
599 pub fn crt_static_feature(&self) -> bool {
600 let requested_features = self.opts.cg.target_feature.split(',');
601 let found_negative = requested_features.clone().any(|r| r == "-crt-static");
602 let found_positive = requested_features.clone().any(|r| r == "+crt-static");
604 // If the target we're compiling for requests a static crt by default,
605 // then see if the `-crt-static` feature was passed to disable that.
606 // Otherwise if we don't have a static crt by default then see if the
607 // `+crt-static` feature was passed.
608 if self.target.target.options.crt_static_default {
615 pub fn must_not_eliminate_frame_pointers(&self) -> bool {
616 self.opts.debuginfo != DebugInfoLevel::NoDebugInfo ||
617 !self.target.target.options.eliminate_frame_pointer
620 /// Returns the symbol name for the registrar function,
621 /// given the crate Svh and the function DefIndex.
622 pub fn generate_plugin_registrar_symbol(&self,
623 disambiguator: CrateDisambiguator)
625 format!("__rustc_plugin_registrar_{}__", disambiguator.to_fingerprint().to_hex())
628 pub fn generate_derive_registrar_symbol(&self,
629 disambiguator: CrateDisambiguator)
631 format!("__rustc_derive_registrar_{}__", disambiguator.to_fingerprint().to_hex())
634 pub fn sysroot<'a>(&'a self) -> &'a Path {
635 match self.opts.maybe_sysroot {
636 Some (ref sysroot) => sysroot,
637 None => self.default_sysroot.as_ref()
638 .expect("missing sysroot and default_sysroot in Session")
641 pub fn target_filesearch(&self, kind: PathKind) -> filesearch::FileSearch {
642 filesearch::FileSearch::new(self.sysroot(),
643 &self.opts.target_triple,
644 &self.opts.search_paths,
647 pub fn host_filesearch(&self, kind: PathKind) -> filesearch::FileSearch {
648 filesearch::FileSearch::new(
650 config::host_triple(),
651 &self.opts.search_paths,
655 pub fn set_incr_session_load_dep_graph(&self, load: bool) {
656 let mut incr_comp_session = self.incr_comp_session.borrow_mut();
658 match *incr_comp_session {
659 IncrCompSession::Active { ref mut load_dep_graph, .. } => {
660 *load_dep_graph = load;
666 pub fn incr_session_load_dep_graph(&self) -> bool {
667 let incr_comp_session = self.incr_comp_session.borrow();
668 match *incr_comp_session {
669 IncrCompSession::Active { load_dep_graph, .. } => load_dep_graph,
674 pub fn init_incr_comp_session(&self,
675 session_dir: PathBuf,
676 lock_file: flock::Lock,
677 load_dep_graph: bool) {
678 let mut incr_comp_session = self.incr_comp_session.borrow_mut();
680 if let IncrCompSession::NotInitialized = *incr_comp_session { } else {
681 bug!("Trying to initialize IncrCompSession `{:?}`", *incr_comp_session)
684 *incr_comp_session = IncrCompSession::Active {
685 session_directory: session_dir,
691 pub fn finalize_incr_comp_session(&self, new_directory_path: PathBuf) {
692 let mut incr_comp_session = self.incr_comp_session.borrow_mut();
694 if let IncrCompSession::Active { .. } = *incr_comp_session { } else {
695 bug!("Trying to finalize IncrCompSession `{:?}`", *incr_comp_session)
698 // Note: This will also drop the lock file, thus unlocking the directory
699 *incr_comp_session = IncrCompSession::Finalized {
700 session_directory: new_directory_path,
704 pub fn mark_incr_comp_session_as_invalid(&self) {
705 let mut incr_comp_session = self.incr_comp_session.borrow_mut();
707 let session_directory = match *incr_comp_session {
708 IncrCompSession::Active { ref session_directory, .. } => {
709 session_directory.clone()
711 IncrCompSession::InvalidBecauseOfErrors { .. } => return,
712 _ => bug!("Trying to invalidate IncrCompSession `{:?}`",
716 // Note: This will also drop the lock file, thus unlocking the directory
717 *incr_comp_session = IncrCompSession::InvalidBecauseOfErrors {
722 pub fn incr_comp_session_dir(&self) -> cell::Ref<PathBuf> {
723 let incr_comp_session = self.incr_comp_session.borrow();
724 cell::Ref::map(incr_comp_session, |incr_comp_session| {
725 match *incr_comp_session {
726 IncrCompSession::NotInitialized => {
727 bug!("Trying to get session directory from IncrCompSession `{:?}`",
730 IncrCompSession::Active { ref session_directory, .. } |
731 IncrCompSession::Finalized { ref session_directory } |
732 IncrCompSession::InvalidBecauseOfErrors { ref session_directory } => {
739 pub fn incr_comp_session_dir_opt(&self) -> Option<cell::Ref<PathBuf>> {
740 if self.opts.incremental.is_some() {
741 Some(self.incr_comp_session_dir())
747 pub fn print_perf_stats(&self) {
748 println!("Total time spent computing SVHs: {}",
749 duration_to_secs_str(self.perf_stats.svh_time.get()));
750 println!("Total time spent computing incr. comp. hashes: {}",
751 duration_to_secs_str(self.perf_stats.incr_comp_hashes_time.get()));
752 println!("Total number of incr. comp. hashes computed: {}",
753 self.perf_stats.incr_comp_hashes_count.get());
754 println!("Total number of bytes hashed for incr. comp.: {}",
755 self.perf_stats.incr_comp_bytes_hashed.get());
756 if self.perf_stats.incr_comp_hashes_count.get() != 0 {
757 println!("Average bytes hashed per incr. comp. HIR node: {}",
758 self.perf_stats.incr_comp_bytes_hashed.get() /
759 self.perf_stats.incr_comp_hashes_count.get());
761 println!("Average bytes hashed per incr. comp. HIR node: N/A");
763 println!("Total time spent computing symbol hashes: {}",
764 duration_to_secs_str(self.perf_stats.symbol_hash_time.get()));
765 println!("Total time spent decoding DefPath tables: {}",
766 duration_to_secs_str(self.perf_stats.decode_def_path_tables_time.get()));
769 /// We want to know if we're allowed to do an optimization for crate foo from -z fuel=foo=n.
770 /// This expends fuel if applicable, and records fuel if applicable.
771 pub fn consider_optimizing<T: Fn() -> String>(&self, crate_name: &str, msg: T) -> bool {
773 match self.optimization_fuel_crate {
774 Some(ref c) if c == crate_name => {
775 let fuel = self.optimization_fuel_limit.get();
777 if fuel == 0 && !self.out_of_fuel.get() {
778 println!("optimization-fuel-exhausted: {}", msg());
779 self.out_of_fuel.set(true);
781 self.optimization_fuel_limit.set(fuel-1);
786 match self.print_fuel_crate {
787 Some(ref c) if c == crate_name=> {
788 self.print_fuel.set(self.print_fuel.get()+1);
795 /// Returns the number of query threads that should be used for this
797 pub fn query_threads(&self) -> usize {
798 self.opts.debugging_opts.query_threads.unwrap_or(1)
801 /// Returns the number of codegen units that should be used for this
803 pub fn codegen_units(&self) -> usize {
804 if let Some(n) = self.opts.cli_forced_codegen_units {
807 if let Some(n) = self.target.target.options.default_codegen_units {
811 // Why is 16 codegen units the default all the time?
813 // The main reason for enabling multiple codegen units by default is to
814 // leverage the ability for the trans backend to do translation and
815 // codegen in parallel. This allows us, especially for large crates, to
816 // make good use of all available resources on the machine once we've
817 // hit that stage of compilation. Large crates especially then often
818 // take a long time in trans/codegen and this helps us amortize that
821 // Note that a high number here doesn't mean that we'll be spawning a
822 // large number of threads in parallel. The backend of rustc contains
823 // global rate limiting through the `jobserver` crate so we'll never
824 // overload the system with too much work, but rather we'll only be
825 // optimizing when we're otherwise cooperating with other instances of
828 // Rather a high number here means that we should be able to keep a lot
829 // of idle cpus busy. By ensuring that no codegen unit takes *too* long
830 // to build we'll be guaranteed that all cpus will finish pretty closely
831 // to one another and we should make relatively optimal use of system
834 // Note that the main cost of codegen units is that it prevents LLVM
835 // from inlining across codegen units. Users in general don't have a lot
836 // of control over how codegen units are split up so it's our job in the
837 // compiler to ensure that undue performance isn't lost when using
838 // codegen units (aka we can't require everyone to slap `#[inline]` on
841 // If we're compiling at `-O0` then the number doesn't really matter too
842 // much because performance doesn't matter and inlining is ok to lose.
843 // In debug mode we just want to try to guarantee that no cpu is stuck
844 // doing work that could otherwise be farmed to others.
846 // In release mode, however (O1 and above) performance does indeed
847 // matter! To recover the loss in performance due to inlining we'll be
848 // enabling ThinLTO by default (the function for which is just below).
849 // This will ensure that we recover any inlining wins we otherwise lost
850 // through codegen unit partitioning.
854 // Ok that's a lot of words but the basic tl;dr; is that we want a high
855 // number here -- but not too high. Additionally we're "safe" to have it
856 // always at the same number at all optimization levels.
858 // As a result 16 was chosen here! Mostly because it was a power of 2
859 // and most benchmarks agreed it was roughly a local optimum. Not very
864 pub fn teach(&self, code: &DiagnosticId) -> bool {
865 self.opts.debugging_opts.teach && !self.parse_sess.span_diagnostic.code_emitted(code)
868 /// Are we allowed to use features from the Rust 2018 epoch?
869 pub fn rust_2018(&self) -> bool {
870 self.opts.debugging_opts.epoch >= Epoch::Epoch2018
874 pub fn build_session(sopts: config::Options,
875 local_crate_source_file: Option<PathBuf>,
876 registry: errors::registry::Registry)
878 let file_path_mapping = sopts.file_path_mapping();
880 build_session_with_codemap(sopts,
881 local_crate_source_file,
883 Rc::new(codemap::CodeMap::new(file_path_mapping)),
887 pub fn build_session_with_codemap(sopts: config::Options,
888 local_crate_source_file: Option<PathBuf>,
889 registry: errors::registry::Registry,
890 codemap: Rc<codemap::CodeMap>,
891 emitter_dest: Option<Box<Write + Send>>)
893 // FIXME: This is not general enough to make the warning lint completely override
894 // normal diagnostic warnings, since the warning lint can also be denied and changed
895 // later via the source code.
896 let warnings_allow = sopts.lint_opts
898 .filter(|&&(ref key, _)| *key == "warnings")
899 .map(|&(_, ref level)| *level == lint::Allow)
902 let cap_lints_allow = sopts.lint_cap.map_or(false, |cap| cap == lint::Allow);
904 let can_emit_warnings = !(warnings_allow || cap_lints_allow);
906 let treat_err_as_bug = sopts.debugging_opts.treat_err_as_bug;
908 let external_macro_backtrace = sopts.debugging_opts.external_macro_backtrace;
910 let emitter: Box<Emitter> = match (sopts.error_format, emitter_dest) {
911 (config::ErrorOutputType::HumanReadable(color_config), None) => {
912 Box::new(EmitterWriter::stderr(color_config,
913 Some(codemap.clone()),
915 sopts.debugging_opts.teach))
917 (config::ErrorOutputType::HumanReadable(_), Some(dst)) => {
918 Box::new(EmitterWriter::new(dst, Some(codemap.clone()), false, false))
920 (config::ErrorOutputType::Json(pretty), None) => {
921 Box::new(JsonEmitter::stderr(Some(registry), codemap.clone(),
922 pretty, sopts.debugging_opts.approximate_suggestions))
924 (config::ErrorOutputType::Json(pretty), Some(dst)) => {
925 Box::new(JsonEmitter::new(dst, Some(registry), codemap.clone(),
926 pretty, sopts.debugging_opts.approximate_suggestions))
928 (config::ErrorOutputType::Short(color_config), None) => {
929 Box::new(EmitterWriter::stderr(color_config, Some(codemap.clone()), true, false))
931 (config::ErrorOutputType::Short(_), Some(dst)) => {
932 Box::new(EmitterWriter::new(dst, Some(codemap.clone()), true, false))
936 let diagnostic_handler =
937 errors::Handler::with_emitter_and_flags(
939 errors::HandlerFlags {
942 external_macro_backtrace,
943 .. Default::default()
946 build_session_(sopts,
947 local_crate_source_file,
952 pub fn build_session_(sopts: config::Options,
953 local_crate_source_file: Option<PathBuf>,
954 span_diagnostic: errors::Handler,
955 codemap: Rc<codemap::CodeMap>)
957 let host = match Target::search(config::host_triple()) {
960 span_diagnostic.fatal(&format!("Error loading host specification: {}", e)).raise();
963 let target_cfg = config::build_target_config(&sopts, &span_diagnostic);
965 let p_s = parse::ParseSess::with_span_handler(span_diagnostic, codemap);
966 let default_sysroot = match sopts.maybe_sysroot {
968 None => Some(filesearch::get_or_default_sysroot())
971 let file_path_mapping = sopts.file_path_mapping();
973 let local_crate_source_file = local_crate_source_file.map(|path| {
974 file_path_mapping.map_prefix(path).0
977 let optimization_fuel_crate = sopts.debugging_opts.fuel.as_ref().map(|i| i.0.clone());
978 let optimization_fuel_limit = Cell::new(sopts.debugging_opts.fuel.as_ref()
979 .map(|i| i.1).unwrap_or(0));
980 let print_fuel_crate = sopts.debugging_opts.print_fuel.clone();
981 let print_fuel = Cell::new(0);
983 let working_dir = match env::current_dir() {
986 p_s.span_diagnostic.fatal(&format!("Current directory is invalid: {}", e)).raise()
989 let working_dir = file_path_mapping.map_prefix(working_dir);
996 // For a library crate, this is always none
997 entry_fn: RefCell::new(None),
998 entry_type: Cell::new(None),
999 plugin_registrar_fn: Cell::new(None),
1000 derive_registrar_fn: Cell::new(None),
1002 local_crate_source_file,
1004 lint_store: RefCell::new(lint::LintStore::new()),
1005 buffered_lints: RefCell::new(Some(lint::LintBuffer::new())),
1006 one_time_diagnostics: RefCell::new(FxHashSet()),
1007 plugin_llvm_passes: RefCell::new(Vec::new()),
1008 plugin_attributes: RefCell::new(Vec::new()),
1009 crate_types: RefCell::new(Vec::new()),
1010 dependency_formats: RefCell::new(FxHashMap()),
1011 crate_disambiguator: RefCell::new(None),
1012 features: RefCell::new(feature_gate::Features::new()),
1013 recursion_limit: Cell::new(64),
1014 type_length_limit: Cell::new(1048576),
1015 next_node_id: Cell::new(NodeId::new(1)),
1016 injected_allocator: Cell::new(None),
1017 allocator_kind: Cell::new(None),
1018 injected_panic_runtime: Cell::new(None),
1019 imported_macro_spans: RefCell::new(HashMap::new()),
1020 incr_comp_session: RefCell::new(IncrCompSession::NotInitialized),
1021 ignored_attr_names: ich::compute_ignored_attr_names(),
1022 perf_stats: PerfStats {
1023 svh_time: Cell::new(Duration::from_secs(0)),
1024 incr_comp_hashes_time: Cell::new(Duration::from_secs(0)),
1025 incr_comp_hashes_count: Cell::new(0),
1026 incr_comp_bytes_hashed: Cell::new(0),
1027 symbol_hash_time: Cell::new(Duration::from_secs(0)),
1028 decode_def_path_tables_time: Cell::new(Duration::from_secs(0)),
1030 code_stats: RefCell::new(CodeStats::new()),
1031 optimization_fuel_crate,
1032 optimization_fuel_limit,
1035 out_of_fuel: Cell::new(false),
1036 // Note that this is unsafe because it may misinterpret file descriptors
1037 // on Unix as jobserver file descriptors. We hopefully execute this near
1038 // the beginning of the process though to ensure we don't get false
1039 // positives, or in other words we try to execute this before we open
1040 // any file descriptors ourselves.
1042 // Also note that we stick this in a global because there could be
1043 // multiple `Session` instances in this process, and the jobserver is
1045 jobserver_from_env: unsafe {
1046 static mut GLOBAL_JOBSERVER: *mut Option<Client> = 0 as *mut _;
1047 static INIT: Once = ONCE_INIT;
1049 GLOBAL_JOBSERVER = Box::into_raw(Box::new(Client::from_env()));
1051 (*GLOBAL_JOBSERVER).clone()
1053 has_global_allocator: Cell::new(false),
1059 /// Hash value constructed out of all the `-C metadata` arguments passed to the
1060 /// compiler. Together with the crate-name forms a unique global identifier for
1062 #[derive(Eq, PartialEq, Ord, PartialOrd, Hash, Debug, Clone, Copy, RustcEncodable, RustcDecodable)]
1063 pub struct CrateDisambiguator(Fingerprint);
1065 impl CrateDisambiguator {
1066 pub fn to_fingerprint(self) -> Fingerprint {
1071 impl From<Fingerprint> for CrateDisambiguator {
1072 fn from(fingerprint: Fingerprint) -> CrateDisambiguator {
1073 CrateDisambiguator(fingerprint)
1077 impl_stable_hash_for!(tuple_struct CrateDisambiguator { fingerprint });
1079 /// Holds data on the current incremental compilation session, if there is one.
1081 pub enum IncrCompSession {
1082 /// This is the state the session will be in until the incr. comp. dir is
1085 /// This is the state during which the session directory is private and can
1088 session_directory: PathBuf,
1089 lock_file: flock::Lock,
1090 load_dep_graph: bool,
1092 /// This is the state after the session directory has been finalized. In this
1093 /// state, the contents of the directory must not be modified any more.
1095 session_directory: PathBuf,
1097 /// This is an error state that is reached when some compilation error has
1098 /// occurred. It indicates that the contents of the session directory must
1099 /// not be used, since they might be invalid.
1100 InvalidBecauseOfErrors {
1101 session_directory: PathBuf,
1105 pub fn early_error(output: config::ErrorOutputType, msg: &str) -> ! {
1106 let emitter: Box<Emitter> = match output {
1107 config::ErrorOutputType::HumanReadable(color_config) => {
1108 Box::new(EmitterWriter::stderr(color_config, None, false, false))
1110 config::ErrorOutputType::Json(pretty) => Box::new(JsonEmitter::basic(pretty)),
1111 config::ErrorOutputType::Short(color_config) => {
1112 Box::new(EmitterWriter::stderr(color_config, None, true, false))
1115 let handler = errors::Handler::with_emitter(true, false, emitter);
1116 handler.emit(&MultiSpan::new(), msg, errors::Level::Fatal);
1117 errors::FatalError.raise();
1120 pub fn early_warn(output: config::ErrorOutputType, msg: &str) {
1121 let emitter: Box<Emitter> = match output {
1122 config::ErrorOutputType::HumanReadable(color_config) => {
1123 Box::new(EmitterWriter::stderr(color_config, None, false, false))
1125 config::ErrorOutputType::Json(pretty) => Box::new(JsonEmitter::basic(pretty)),
1126 config::ErrorOutputType::Short(color_config) => {
1127 Box::new(EmitterWriter::stderr(color_config, None, true, false))
1130 let handler = errors::Handler::with_emitter(true, false, emitter);
1131 handler.emit(&MultiSpan::new(), msg, errors::Level::Warning);
1134 #[derive(Copy, Clone, Debug)]
1135 pub enum CompileIncomplete {
1137 Errored(ErrorReported)
1139 impl From<ErrorReported> for CompileIncomplete {
1140 fn from(err: ErrorReported) -> CompileIncomplete {
1141 CompileIncomplete::Errored(err)
1144 pub type CompileResult = Result<(), CompileIncomplete>;
1146 pub fn compile_result_from_err_count(err_count: usize) -> CompileResult {
1150 Err(CompileIncomplete::Errored(ErrorReported))
1156 pub fn bug_fmt(file: &'static str, line: u32, args: fmt::Arguments) -> ! {
1157 // this wrapper mostly exists so I don't have to write a fully
1158 // qualified path of None::<Span> inside the bug!() macro definition
1159 opt_span_bug_fmt(file, line, None::<Span>, args);
1164 pub fn span_bug_fmt<S: Into<MultiSpan>>(file: &'static str,
1167 args: fmt::Arguments) -> ! {
1168 opt_span_bug_fmt(file, line, Some(span), args);
1171 fn opt_span_bug_fmt<S: Into<MultiSpan>>(file: &'static str,
1174 args: fmt::Arguments) -> ! {
1175 tls::with_opt(move |tcx| {
1176 let msg = format!("{}:{}: {}", file, line, args);
1178 (Some(tcx), Some(span)) => tcx.sess.diagnostic().span_bug(span, &msg),
1179 (Some(tcx), None) => tcx.sess.diagnostic().bug(&msg),
1180 (None, _) => panic!(msg)