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, DefIndex};
18 use middle::allocator::AllocatorKind;
19 use middle::dependency_format;
20 use session::search_paths::PathKind;
21 use session::config::{BorrowckMode, DebugInfoLevel};
23 use util::nodemap::{FxHashMap, FxHashSet};
24 use util::common::{duration_to_secs_str, ErrorReported};
26 use syntax::ast::NodeId;
27 use errors::{self, DiagnosticBuilder, DiagnosticId};
28 use errors::emitter::{Emitter, EmitterWriter};
29 use syntax::json::JsonEmitter;
30 use syntax::feature_gate;
32 use syntax::parse::ParseSess;
33 use syntax::{ast, codemap};
34 use syntax::feature_gate::AttributeType;
35 use syntax_pos::{Span, MultiSpan};
37 use rustc_back::{LinkerFlavor, PanicStrategy};
38 use rustc_back::target::Target;
39 use rustc_data_structures::flock;
40 use jobserver::Client;
42 use std::cell::{self, Cell, RefCell};
43 use std::collections::HashMap;
47 use std::path::{Path, PathBuf};
49 use std::sync::{Once, ONCE_INIT};
50 use std::time::Duration;
57 /// Represents the data associated with a compilation
58 /// session for a single crate.
60 pub target: config::Config,
62 pub opts: config::Options,
63 pub parse_sess: ParseSess,
64 /// For a library crate, this is always none
65 pub entry_fn: RefCell<Option<(NodeId, Span)>>,
66 pub entry_type: Cell<Option<config::EntryFnType>>,
67 pub plugin_registrar_fn: Cell<Option<ast::NodeId>>,
68 pub derive_registrar_fn: Cell<Option<ast::NodeId>>,
69 pub default_sysroot: Option<PathBuf>,
70 /// The name of the root source file of the crate, in the local file system.
71 /// `None` means that there is no source file.
72 pub local_crate_source_file: Option<PathBuf>,
73 /// The directory the compiler has been executed in plus a flag indicating
74 /// if the value stored here has been affected by path remapping.
75 pub working_dir: (PathBuf, bool),
76 pub lint_store: RefCell<lint::LintStore>,
77 pub buffered_lints: RefCell<Option<lint::LintBuffer>>,
78 /// Set of (DiagnosticId, Option<Span>, message) tuples tracking
79 /// (sub)diagnostics that have been set once, but should not be set again,
80 /// in order to avoid redundantly verbose output (Issue #24690, #44953).
81 pub one_time_diagnostics: RefCell<FxHashSet<(DiagnosticMessageId, Option<Span>, String)>>,
82 pub plugin_llvm_passes: RefCell<Vec<String>>,
83 pub plugin_attributes: RefCell<Vec<(String, AttributeType)>>,
84 pub crate_types: RefCell<Vec<config::CrateType>>,
85 pub dependency_formats: RefCell<dependency_format::Dependencies>,
86 /// The crate_disambiguator is constructed out of all the `-C metadata`
87 /// arguments passed to the compiler. Its value together with the crate-name
88 /// forms a unique global identifier for the crate. It is used to allow
89 /// multiple crates with the same name to coexist. See the
90 /// trans::back::symbol_names module for more information.
91 pub crate_disambiguator: RefCell<Option<CrateDisambiguator>>,
92 pub features: RefCell<feature_gate::Features>,
94 /// The maximum recursion limit for potentially infinitely recursive
95 /// operations such as auto-dereference and monomorphization.
96 pub recursion_limit: Cell<usize>,
98 /// The maximum length of types during monomorphization.
99 pub type_length_limit: Cell<usize>,
101 /// The metadata::creader module may inject an allocator/panic_runtime
102 /// dependency if it didn't already find one, and this tracks what was
104 pub injected_allocator: Cell<Option<CrateNum>>,
105 pub allocator_kind: Cell<Option<AllocatorKind>>,
106 pub injected_panic_runtime: Cell<Option<CrateNum>>,
108 /// Map from imported macro spans (which consist of
109 /// the localized span for the macro body) to the
110 /// macro name and definition span in the source crate.
111 pub imported_macro_spans: RefCell<HashMap<Span, (String, Span)>>,
113 incr_comp_session: RefCell<IncrCompSession>,
115 /// Some measurements that are being gathered during compilation.
116 pub perf_stats: PerfStats,
118 /// Data about code being compiled, gathered during compilation.
119 pub code_stats: RefCell<CodeStats>,
121 next_node_id: Cell<ast::NodeId>,
123 /// If -zfuel=crate=n is specified, Some(crate).
124 optimization_fuel_crate: Option<String>,
125 /// If -zfuel=crate=n is specified, initially set to n. Otherwise 0.
126 optimization_fuel_limit: Cell<u64>,
127 /// We're rejecting all further optimizations.
128 out_of_fuel: Cell<bool>,
130 // The next two are public because the driver needs to read them.
132 /// If -zprint-fuel=crate, Some(crate).
133 pub print_fuel_crate: Option<String>,
134 /// Always set to zero and incremented so that we can print fuel expended by a crate.
135 pub print_fuel: Cell<u64>,
137 /// Loaded up early on in the initialization of this `Session` to avoid
138 /// false positives about a job server in our environment.
139 pub jobserver_from_env: Option<Client>,
141 /// Metadata about the allocators for the current crate being compiled
142 pub has_global_allocator: Cell<bool>,
145 pub struct PerfStats {
146 /// The accumulated time needed for computing the SVH of the crate
147 pub svh_time: Cell<Duration>,
148 /// The accumulated time spent on computing incr. comp. hashes
149 pub incr_comp_hashes_time: Cell<Duration>,
150 /// The number of incr. comp. hash computations performed
151 pub incr_comp_hashes_count: Cell<u64>,
152 /// The number of bytes hashed when computing ICH values
153 pub incr_comp_bytes_hashed: Cell<u64>,
154 /// The accumulated time spent on computing symbol hashes
155 pub symbol_hash_time: Cell<Duration>,
156 /// The accumulated time spent decoding def path tables from metadata
157 pub decode_def_path_tables_time: Cell<Duration>,
160 /// Enum to support dispatch of one-time diagnostics (in Session.diag_once)
161 enum DiagnosticBuilderMethod {
164 SpanSuggestion(String), // suggestion
165 // add more variants as needed to support one-time diagnostics
168 /// Diagnostic message ID—used by `Session.one_time_diagnostics` to avoid
169 /// emitting the same message more than once
170 #[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
171 pub enum DiagnosticMessageId {
172 ErrorId(u16), // EXXXX error code as integer
173 LintId(lint::LintId),
174 StabilityId(u32) // issue number
177 impl From<&'static lint::Lint> for DiagnosticMessageId {
178 fn from(lint: &'static lint::Lint) -> Self {
179 DiagnosticMessageId::LintId(lint::LintId::of(lint))
184 pub fn local_crate_disambiguator(&self) -> CrateDisambiguator {
185 match *self.crate_disambiguator.borrow() {
186 Some(value) => value,
187 None => bug!("accessing disambiguator before initialization"),
190 pub fn struct_span_warn<'a, S: Into<MultiSpan>>(&'a self,
193 -> DiagnosticBuilder<'a> {
194 self.diagnostic().struct_span_warn(sp, msg)
196 pub fn struct_span_warn_with_code<'a, S: Into<MultiSpan>>(&'a self,
200 -> DiagnosticBuilder<'a> {
201 self.diagnostic().struct_span_warn_with_code(sp, msg, code)
203 pub fn struct_warn<'a>(&'a self, msg: &str) -> DiagnosticBuilder<'a> {
204 self.diagnostic().struct_warn(msg)
206 pub fn struct_span_err<'a, S: Into<MultiSpan>>(&'a self,
209 -> DiagnosticBuilder<'a> {
210 self.diagnostic().struct_span_err(sp, msg)
212 pub fn struct_span_err_with_code<'a, S: Into<MultiSpan>>(&'a self,
216 -> DiagnosticBuilder<'a> {
217 self.diagnostic().struct_span_err_with_code(sp, msg, code)
219 // FIXME: This method should be removed (every error should have an associated error code).
220 pub fn struct_err<'a>(&'a self, msg: &str) -> DiagnosticBuilder<'a> {
221 self.diagnostic().struct_err(msg)
223 pub fn struct_err_with_code<'a>(
227 ) -> DiagnosticBuilder<'a> {
228 self.diagnostic().struct_err_with_code(msg, code)
230 pub fn struct_span_fatal<'a, S: Into<MultiSpan>>(&'a self,
233 -> DiagnosticBuilder<'a> {
234 self.diagnostic().struct_span_fatal(sp, msg)
236 pub fn struct_span_fatal_with_code<'a, S: Into<MultiSpan>>(&'a self,
240 -> DiagnosticBuilder<'a> {
241 self.diagnostic().struct_span_fatal_with_code(sp, msg, code)
243 pub fn struct_fatal<'a>(&'a self, msg: &str) -> DiagnosticBuilder<'a> {
244 self.diagnostic().struct_fatal(msg)
247 pub fn span_fatal<S: Into<MultiSpan>>(&self, sp: S, msg: &str) -> ! {
248 panic!(self.diagnostic().span_fatal(sp, msg))
250 pub fn span_fatal_with_code<S: Into<MultiSpan>>(
256 panic!(self.diagnostic().span_fatal_with_code(sp, msg, code))
258 pub fn fatal(&self, msg: &str) -> ! {
259 panic!(self.diagnostic().fatal(msg))
261 pub fn span_err_or_warn<S: Into<MultiSpan>>(&self, is_warning: bool, sp: S, msg: &str) {
263 self.span_warn(sp, msg);
265 self.span_err(sp, msg);
268 pub fn span_err<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
269 self.diagnostic().span_err(sp, msg)
271 pub fn span_err_with_code<S: Into<MultiSpan>>(&self, sp: S, msg: &str, code: DiagnosticId) {
272 self.diagnostic().span_err_with_code(sp, &msg, code)
274 pub fn err(&self, msg: &str) {
275 self.diagnostic().err(msg)
277 pub fn err_count(&self) -> usize {
278 self.diagnostic().err_count()
280 pub fn has_errors(&self) -> bool {
281 self.diagnostic().has_errors()
283 pub fn abort_if_errors(&self) {
284 self.diagnostic().abort_if_errors();
286 pub fn compile_status(&self) -> Result<(), CompileIncomplete> {
287 compile_result_from_err_count(self.err_count())
289 pub fn track_errors<F, T>(&self, f: F) -> Result<T, ErrorReported>
290 where F: FnOnce() -> T
292 let old_count = self.err_count();
294 let errors = self.err_count() - old_count;
301 pub fn span_warn<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
302 self.diagnostic().span_warn(sp, msg)
304 pub fn span_warn_with_code<S: Into<MultiSpan>>(&self, sp: S, msg: &str, code: DiagnosticId) {
305 self.diagnostic().span_warn_with_code(sp, msg, code)
307 pub fn warn(&self, msg: &str) {
308 self.diagnostic().warn(msg)
310 pub fn opt_span_warn<S: Into<MultiSpan>>(&self, opt_sp: Option<S>, msg: &str) {
312 Some(sp) => self.span_warn(sp, msg),
313 None => self.warn(msg),
316 /// Delay a span_bug() call until abort_if_errors()
317 pub fn delay_span_bug<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
318 self.diagnostic().delay_span_bug(sp, msg)
320 pub fn note_without_error(&self, msg: &str) {
321 self.diagnostic().note_without_error(msg)
323 pub fn span_note_without_error<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
324 self.diagnostic().span_note_without_error(sp, msg)
326 pub fn span_unimpl<S: Into<MultiSpan>>(&self, sp: S, msg: &str) -> ! {
327 self.diagnostic().span_unimpl(sp, msg)
329 pub fn unimpl(&self, msg: &str) -> ! {
330 self.diagnostic().unimpl(msg)
333 pub fn buffer_lint<S: Into<MultiSpan>>(&self,
334 lint: &'static lint::Lint,
338 match *self.buffered_lints.borrow_mut() {
339 Some(ref mut buffer) => buffer.add_lint(lint, id, sp.into(), msg),
340 None => bug!("can't buffer lints after HIR lowering"),
344 pub fn reserve_node_ids(&self, count: usize) -> ast::NodeId {
345 let id = self.next_node_id.get();
347 match id.as_usize().checked_add(count) {
349 self.next_node_id.set(ast::NodeId::new(next));
351 None => bug!("Input too large, ran out of node ids!")
356 pub fn next_node_id(&self) -> NodeId {
357 self.reserve_node_ids(1)
359 pub fn diagnostic<'a>(&'a self) -> &'a errors::Handler {
360 &self.parse_sess.span_diagnostic
363 /// Analogous to calling methods on the given `DiagnosticBuilder`, but
364 /// deduplicates on lint ID, span (if any), and message for this `Session`
365 fn diag_once<'a, 'b>(&'a self,
366 diag_builder: &'b mut DiagnosticBuilder<'a>,
367 method: DiagnosticBuilderMethod,
368 msg_id: DiagnosticMessageId,
370 span_maybe: Option<Span>) {
372 let id_span_message = (msg_id, span_maybe, message.to_owned());
373 let fresh = self.one_time_diagnostics.borrow_mut().insert(id_span_message);
376 DiagnosticBuilderMethod::Note => {
377 diag_builder.note(message);
379 DiagnosticBuilderMethod::SpanNote => {
380 let span = span_maybe.expect("span_note needs a span");
381 diag_builder.span_note(span, message);
383 DiagnosticBuilderMethod::SpanSuggestion(suggestion) => {
384 let span = span_maybe.expect("span_suggestion needs a span");
385 diag_builder.span_suggestion(span, message, suggestion);
391 pub fn diag_span_note_once<'a, 'b>(&'a self,
392 diag_builder: &'b mut DiagnosticBuilder<'a>,
393 msg_id: DiagnosticMessageId, span: Span, message: &str) {
394 self.diag_once(diag_builder, DiagnosticBuilderMethod::SpanNote,
395 msg_id, message, Some(span));
398 pub fn diag_note_once<'a, 'b>(&'a self,
399 diag_builder: &'b mut DiagnosticBuilder<'a>,
400 msg_id: DiagnosticMessageId, message: &str) {
401 self.diag_once(diag_builder, DiagnosticBuilderMethod::Note, msg_id, message, None);
404 pub fn diag_span_suggestion_once<'a, 'b>(&'a self,
405 diag_builder: &'b mut DiagnosticBuilder<'a>,
406 msg_id: DiagnosticMessageId,
409 suggestion: String) {
410 self.diag_once(diag_builder, DiagnosticBuilderMethod::SpanSuggestion(suggestion),
411 msg_id, message, Some(span));
414 pub fn codemap<'a>(&'a self) -> &'a codemap::CodeMap {
415 self.parse_sess.codemap()
417 pub fn verbose(&self) -> bool { self.opts.debugging_opts.verbose }
418 pub fn time_passes(&self) -> bool { self.opts.debugging_opts.time_passes }
419 pub fn profile_queries(&self) -> bool {
420 self.opts.debugging_opts.profile_queries ||
421 self.opts.debugging_opts.profile_queries_and_keys
423 pub fn profile_queries_and_keys(&self) -> bool {
424 self.opts.debugging_opts.profile_queries_and_keys
426 pub fn count_llvm_insns(&self) -> bool {
427 self.opts.debugging_opts.count_llvm_insns
429 pub fn time_llvm_passes(&self) -> bool {
430 self.opts.debugging_opts.time_llvm_passes
432 pub fn trans_stats(&self) -> bool { self.opts.debugging_opts.trans_stats }
433 pub fn meta_stats(&self) -> bool { self.opts.debugging_opts.meta_stats }
434 pub fn asm_comments(&self) -> bool { self.opts.debugging_opts.asm_comments }
435 pub fn no_verify(&self) -> bool { self.opts.debugging_opts.no_verify }
436 pub fn borrowck_stats(&self) -> bool { self.opts.debugging_opts.borrowck_stats }
437 pub fn print_llvm_passes(&self) -> bool {
438 self.opts.debugging_opts.print_llvm_passes
441 /// If true, we should use NLL-style region checking instead of
443 pub fn nll(&self) -> bool {
444 self.features.borrow().nll || self.opts.debugging_opts.nll
447 /// If true, we should use the MIR-based borrowck (we may *also* use
448 /// the AST-based borrowck).
449 pub fn use_mir(&self) -> bool {
450 self.borrowck_mode().use_mir()
453 /// If true, we should gather causal information during NLL
454 /// checking. This will eventually be the normal thing, but right
455 /// now it is too unoptimized.
456 pub fn nll_dump_cause(&self) -> bool {
457 self.opts.debugging_opts.nll_dump_cause
460 /// If true, we should enable two-phase borrows checks. This is
461 /// done with either `-Ztwo-phase-borrows` or with
462 /// `#![feature(nll)]`.
463 pub fn two_phase_borrows(&self) -> bool {
464 self.features.borrow().nll || self.opts.debugging_opts.two_phase_borrows
467 /// What mode(s) of borrowck should we run? AST? MIR? both?
468 /// (Also considers the `#![feature(nll)]` setting.)
469 pub fn borrowck_mode(&self) -> BorrowckMode {
470 match self.opts.borrowck_mode {
471 mode @ BorrowckMode::Mir |
472 mode @ BorrowckMode::Compare => mode,
474 mode @ BorrowckMode::Ast => {
485 /// Should we emit EndRegion MIR statements? These are consumed by
486 /// MIR borrowck, but not when NLL is used. They are also consumed
487 /// by the validation stuff.
488 pub fn emit_end_regions(&self) -> bool {
489 // FIXME(#46875) -- we should not emit end regions when NLL is enabled,
490 // but for now we can't stop doing so because it causes false positives
491 self.opts.debugging_opts.emit_end_regions ||
492 self.opts.debugging_opts.mir_emit_validate > 0 ||
496 pub fn lto(&self) -> bool {
497 self.opts.cg.lto || self.target.target.options.requires_lto
499 /// Returns the panic strategy for this compile session. If the user explicitly selected one
500 /// using '-C panic', use that, otherwise use the panic strategy defined by the target.
501 pub fn panic_strategy(&self) -> PanicStrategy {
502 self.opts.cg.panic.unwrap_or(self.target.target.options.panic_strategy)
504 pub fn linker_flavor(&self) -> LinkerFlavor {
505 self.opts.debugging_opts.linker_flavor.unwrap_or(self.target.target.linker_flavor)
507 pub fn no_landing_pads(&self) -> bool {
508 self.opts.debugging_opts.no_landing_pads || self.panic_strategy() == PanicStrategy::Abort
510 pub fn unstable_options(&self) -> bool {
511 self.opts.debugging_opts.unstable_options
513 pub fn nonzeroing_move_hints(&self) -> bool {
514 self.opts.debugging_opts.enable_nonzeroing_move_hints
516 pub fn overflow_checks(&self) -> bool {
517 self.opts.cg.overflow_checks
518 .or(self.opts.debugging_opts.force_overflow_checks)
519 .unwrap_or(self.opts.debug_assertions)
522 pub fn crt_static(&self) -> bool {
523 // If the target does not opt in to crt-static support, use its default.
524 if self.target.target.options.crt_static_respected {
525 self.crt_static_feature()
527 self.target.target.options.crt_static_default
531 pub fn crt_static_feature(&self) -> bool {
532 let requested_features = self.opts.cg.target_feature.split(',');
533 let found_negative = requested_features.clone().any(|r| r == "-crt-static");
534 let found_positive = requested_features.clone().any(|r| r == "+crt-static");
536 // If the target we're compiling for requests a static crt by default,
537 // then see if the `-crt-static` feature was passed to disable that.
538 // Otherwise if we don't have a static crt by default then see if the
539 // `+crt-static` feature was passed.
540 if self.target.target.options.crt_static_default {
547 pub fn must_not_eliminate_frame_pointers(&self) -> bool {
548 self.opts.debuginfo != DebugInfoLevel::NoDebugInfo ||
549 !self.target.target.options.eliminate_frame_pointer
552 /// Returns the symbol name for the registrar function,
553 /// given the crate Svh and the function DefIndex.
554 pub fn generate_plugin_registrar_symbol(&self, disambiguator: CrateDisambiguator,
557 format!("__rustc_plugin_registrar__{}_{}", disambiguator.to_fingerprint().to_hex(),
561 pub fn generate_derive_registrar_symbol(&self, disambiguator: CrateDisambiguator,
564 format!("__rustc_derive_registrar__{}_{}", disambiguator.to_fingerprint().to_hex(),
568 pub fn sysroot<'a>(&'a self) -> &'a Path {
569 match self.opts.maybe_sysroot {
570 Some (ref sysroot) => sysroot,
571 None => self.default_sysroot.as_ref()
572 .expect("missing sysroot and default_sysroot in Session")
575 pub fn target_filesearch(&self, kind: PathKind) -> filesearch::FileSearch {
576 filesearch::FileSearch::new(self.sysroot(),
577 &self.opts.target_triple,
578 &self.opts.search_paths,
581 pub fn host_filesearch(&self, kind: PathKind) -> filesearch::FileSearch {
582 filesearch::FileSearch::new(
584 config::host_triple(),
585 &self.opts.search_paths,
589 pub fn set_incr_session_load_dep_graph(&self, load: bool) {
590 let mut incr_comp_session = self.incr_comp_session.borrow_mut();
592 match *incr_comp_session {
593 IncrCompSession::Active { ref mut load_dep_graph, .. } => {
594 *load_dep_graph = load;
600 pub fn incr_session_load_dep_graph(&self) -> bool {
601 let incr_comp_session = self.incr_comp_session.borrow();
602 match *incr_comp_session {
603 IncrCompSession::Active { load_dep_graph, .. } => load_dep_graph,
608 pub fn init_incr_comp_session(&self,
609 session_dir: PathBuf,
610 lock_file: flock::Lock,
611 load_dep_graph: bool) {
612 let mut incr_comp_session = self.incr_comp_session.borrow_mut();
614 if let IncrCompSession::NotInitialized = *incr_comp_session { } else {
615 bug!("Trying to initialize IncrCompSession `{:?}`", *incr_comp_session)
618 *incr_comp_session = IncrCompSession::Active {
619 session_directory: session_dir,
625 pub fn finalize_incr_comp_session(&self, new_directory_path: PathBuf) {
626 let mut incr_comp_session = self.incr_comp_session.borrow_mut();
628 if let IncrCompSession::Active { .. } = *incr_comp_session { } else {
629 bug!("Trying to finalize IncrCompSession `{:?}`", *incr_comp_session)
632 // Note: This will also drop the lock file, thus unlocking the directory
633 *incr_comp_session = IncrCompSession::Finalized {
634 session_directory: new_directory_path,
638 pub fn mark_incr_comp_session_as_invalid(&self) {
639 let mut incr_comp_session = self.incr_comp_session.borrow_mut();
641 let session_directory = match *incr_comp_session {
642 IncrCompSession::Active { ref session_directory, .. } => {
643 session_directory.clone()
645 IncrCompSession::InvalidBecauseOfErrors { .. } => return,
646 _ => bug!("Trying to invalidate IncrCompSession `{:?}`",
650 // Note: This will also drop the lock file, thus unlocking the directory
651 *incr_comp_session = IncrCompSession::InvalidBecauseOfErrors {
656 pub fn incr_comp_session_dir(&self) -> cell::Ref<PathBuf> {
657 let incr_comp_session = self.incr_comp_session.borrow();
658 cell::Ref::map(incr_comp_session, |incr_comp_session| {
659 match *incr_comp_session {
660 IncrCompSession::NotInitialized => {
661 bug!("Trying to get session directory from IncrCompSession `{:?}`",
664 IncrCompSession::Active { ref session_directory, .. } |
665 IncrCompSession::Finalized { ref session_directory } |
666 IncrCompSession::InvalidBecauseOfErrors { ref session_directory } => {
673 pub fn incr_comp_session_dir_opt(&self) -> Option<cell::Ref<PathBuf>> {
674 if self.opts.incremental.is_some() {
675 Some(self.incr_comp_session_dir())
681 pub fn print_perf_stats(&self) {
682 println!("Total time spent computing SVHs: {}",
683 duration_to_secs_str(self.perf_stats.svh_time.get()));
684 println!("Total time spent computing incr. comp. hashes: {}",
685 duration_to_secs_str(self.perf_stats.incr_comp_hashes_time.get()));
686 println!("Total number of incr. comp. hashes computed: {}",
687 self.perf_stats.incr_comp_hashes_count.get());
688 println!("Total number of bytes hashed for incr. comp.: {}",
689 self.perf_stats.incr_comp_bytes_hashed.get());
690 if self.perf_stats.incr_comp_hashes_count.get() != 0 {
691 println!("Average bytes hashed per incr. comp. HIR node: {}",
692 self.perf_stats.incr_comp_bytes_hashed.get() /
693 self.perf_stats.incr_comp_hashes_count.get());
695 println!("Average bytes hashed per incr. comp. HIR node: N/A");
697 println!("Total time spent computing symbol hashes: {}",
698 duration_to_secs_str(self.perf_stats.symbol_hash_time.get()));
699 println!("Total time spent decoding DefPath tables: {}",
700 duration_to_secs_str(self.perf_stats.decode_def_path_tables_time.get()));
703 /// We want to know if we're allowed to do an optimization for crate foo from -z fuel=foo=n.
704 /// This expends fuel if applicable, and records fuel if applicable.
705 pub fn consider_optimizing<T: Fn() -> String>(&self, crate_name: &str, msg: T) -> bool {
707 match self.optimization_fuel_crate {
708 Some(ref c) if c == crate_name => {
709 let fuel = self.optimization_fuel_limit.get();
711 if fuel == 0 && !self.out_of_fuel.get() {
712 println!("optimization-fuel-exhausted: {}", msg());
713 self.out_of_fuel.set(true);
715 self.optimization_fuel_limit.set(fuel-1);
720 match self.print_fuel_crate {
721 Some(ref c) if c == crate_name=> {
722 self.print_fuel.set(self.print_fuel.get()+1);
729 /// Returns the number of query threads that should be used for this
731 pub fn query_threads(&self) -> usize {
732 self.opts.debugging_opts.query_threads.unwrap_or(1)
735 /// Returns the number of codegen units that should be used for this
737 pub fn codegen_units(&self) -> usize {
738 if let Some(n) = self.opts.cli_forced_codegen_units {
741 if let Some(n) = self.target.target.options.default_codegen_units {
745 // Why is 16 codegen units the default all the time?
747 // The main reason for enabling multiple codegen units by default is to
748 // leverage the ability for the trans backend to do translation and
749 // codegen in parallel. This allows us, especially for large crates, to
750 // make good use of all available resources on the machine once we've
751 // hit that stage of compilation. Large crates especially then often
752 // take a long time in trans/codegen and this helps us amortize that
755 // Note that a high number here doesn't mean that we'll be spawning a
756 // large number of threads in parallel. The backend of rustc contains
757 // global rate limiting through the `jobserver` crate so we'll never
758 // overload the system with too much work, but rather we'll only be
759 // optimizing when we're otherwise cooperating with other instances of
762 // Rather a high number here means that we should be able to keep a lot
763 // of idle cpus busy. By ensuring that no codegen unit takes *too* long
764 // to build we'll be guaranteed that all cpus will finish pretty closely
765 // to one another and we should make relatively optimal use of system
768 // Note that the main cost of codegen units is that it prevents LLVM
769 // from inlining across codegen units. Users in general don't have a lot
770 // of control over how codegen units are split up so it's our job in the
771 // compiler to ensure that undue performance isn't lost when using
772 // codegen units (aka we can't require everyone to slap `#[inline]` on
775 // If we're compiling at `-O0` then the number doesn't really matter too
776 // much because performance doesn't matter and inlining is ok to lose.
777 // In debug mode we just want to try to guarantee that no cpu is stuck
778 // doing work that could otherwise be farmed to others.
780 // In release mode, however (O1 and above) performance does indeed
781 // matter! To recover the loss in performance due to inlining we'll be
782 // enabling ThinLTO by default (the function for which is just below).
783 // This will ensure that we recover any inlining wins we otherwise lost
784 // through codegen unit partitioning.
788 // Ok that's a lot of words but the basic tl;dr; is that we want a high
789 // number here -- but not too high. Additionally we're "safe" to have it
790 // always at the same number at all optimization levels.
792 // As a result 16 was chosen here! Mostly because it was a power of 2
793 // and most benchmarks agreed it was roughly a local optimum. Not very
798 /// Returns whether ThinLTO is enabled for this compilation
799 pub fn thinlto(&self) -> bool {
800 // If processing command line options determined that we're incompatible
801 // with ThinLTO (e.g. `-C lto --emit llvm-ir`) then return that option.
802 if let Some(enabled) = self.opts.cli_forced_thinlto {
806 // If explicitly specified, use that with the next highest priority
807 if let Some(enabled) = self.opts.debugging_opts.thinlto {
811 // If there's only one codegen unit and LTO isn't enabled then there's
812 // no need for ThinLTO so just return false.
813 if self.codegen_units() == 1 && !self.lto() {
817 // Right now ThinLTO isn't compatible with incremental compilation.
818 if self.opts.incremental.is_some() {
822 // Now we're in "defaults" territory. By default we enable ThinLTO for
823 // optimized compiles (anything greater than O0).
824 match self.opts.optimize {
825 config::OptLevel::No => false,
831 pub fn build_session(sopts: config::Options,
832 local_crate_source_file: Option<PathBuf>,
833 registry: errors::registry::Registry)
835 let file_path_mapping = sopts.file_path_mapping();
837 build_session_with_codemap(sopts,
838 local_crate_source_file,
840 Rc::new(codemap::CodeMap::new(file_path_mapping)),
844 pub fn build_session_with_codemap(sopts: config::Options,
845 local_crate_source_file: Option<PathBuf>,
846 registry: errors::registry::Registry,
847 codemap: Rc<codemap::CodeMap>,
848 emitter_dest: Option<Box<Write + Send>>)
850 // FIXME: This is not general enough to make the warning lint completely override
851 // normal diagnostic warnings, since the warning lint can also be denied and changed
852 // later via the source code.
853 let warnings_allow = sopts.lint_opts
855 .filter(|&&(ref key, _)| *key == "warnings")
856 .map(|&(_, ref level)| *level == lint::Allow)
859 let cap_lints_allow = sopts.lint_cap.map_or(false, |cap| cap == lint::Allow);
861 let can_emit_warnings = !(warnings_allow || cap_lints_allow);
863 let treat_err_as_bug = sopts.debugging_opts.treat_err_as_bug;
865 let external_macro_backtrace = sopts.debugging_opts.external_macro_backtrace;
867 let emitter: Box<Emitter> = match (sopts.error_format, emitter_dest) {
868 (config::ErrorOutputType::HumanReadable(color_config), None) => {
869 Box::new(EmitterWriter::stderr(color_config, Some(codemap.clone()), false))
871 (config::ErrorOutputType::HumanReadable(_), Some(dst)) => {
872 Box::new(EmitterWriter::new(dst, Some(codemap.clone()), false))
874 (config::ErrorOutputType::Json(pretty), None) => {
875 Box::new(JsonEmitter::stderr(Some(registry), codemap.clone(), pretty))
877 (config::ErrorOutputType::Json(pretty), Some(dst)) => {
878 Box::new(JsonEmitter::new(dst, Some(registry), codemap.clone(), pretty))
880 (config::ErrorOutputType::Short(color_config), None) => {
881 Box::new(EmitterWriter::stderr(color_config, Some(codemap.clone()), true))
883 (config::ErrorOutputType::Short(_), Some(dst)) => {
884 Box::new(EmitterWriter::new(dst, Some(codemap.clone()), true))
888 let diagnostic_handler =
889 errors::Handler::with_emitter_and_flags(
891 errors::HandlerFlags {
894 external_macro_backtrace,
895 .. Default::default()
898 build_session_(sopts,
899 local_crate_source_file,
904 pub fn build_session_(sopts: config::Options,
905 local_crate_source_file: Option<PathBuf>,
906 span_diagnostic: errors::Handler,
907 codemap: Rc<codemap::CodeMap>)
909 let host = match Target::search(config::host_triple()) {
912 panic!(span_diagnostic.fatal(&format!("Error loading host specification: {}", e)));
915 let target_cfg = config::build_target_config(&sopts, &span_diagnostic);
917 let p_s = parse::ParseSess::with_span_handler(span_diagnostic, codemap);
918 let default_sysroot = match sopts.maybe_sysroot {
920 None => Some(filesearch::get_or_default_sysroot())
923 let file_path_mapping = sopts.file_path_mapping();
925 let local_crate_source_file = local_crate_source_file.map(|path| {
926 file_path_mapping.map_prefix(path).0
929 let optimization_fuel_crate = sopts.debugging_opts.fuel.as_ref().map(|i| i.0.clone());
930 let optimization_fuel_limit = Cell::new(sopts.debugging_opts.fuel.as_ref()
931 .map(|i| i.1).unwrap_or(0));
932 let print_fuel_crate = sopts.debugging_opts.print_fuel.clone();
933 let print_fuel = Cell::new(0);
935 let working_dir = match env::current_dir() {
938 panic!(p_s.span_diagnostic.fatal(&format!("Current directory is invalid: {}", e)))
941 let working_dir = file_path_mapping.map_prefix(working_dir);
948 // For a library crate, this is always none
949 entry_fn: RefCell::new(None),
950 entry_type: Cell::new(None),
951 plugin_registrar_fn: Cell::new(None),
952 derive_registrar_fn: Cell::new(None),
954 local_crate_source_file,
956 lint_store: RefCell::new(lint::LintStore::new()),
957 buffered_lints: RefCell::new(Some(lint::LintBuffer::new())),
958 one_time_diagnostics: RefCell::new(FxHashSet()),
959 plugin_llvm_passes: RefCell::new(Vec::new()),
960 plugin_attributes: RefCell::new(Vec::new()),
961 crate_types: RefCell::new(Vec::new()),
962 dependency_formats: RefCell::new(FxHashMap()),
963 crate_disambiguator: RefCell::new(None),
964 features: RefCell::new(feature_gate::Features::new()),
965 recursion_limit: Cell::new(64),
966 type_length_limit: Cell::new(1048576),
967 next_node_id: Cell::new(NodeId::new(1)),
968 injected_allocator: Cell::new(None),
969 allocator_kind: Cell::new(None),
970 injected_panic_runtime: Cell::new(None),
971 imported_macro_spans: RefCell::new(HashMap::new()),
972 incr_comp_session: RefCell::new(IncrCompSession::NotInitialized),
973 perf_stats: PerfStats {
974 svh_time: Cell::new(Duration::from_secs(0)),
975 incr_comp_hashes_time: Cell::new(Duration::from_secs(0)),
976 incr_comp_hashes_count: Cell::new(0),
977 incr_comp_bytes_hashed: Cell::new(0),
978 symbol_hash_time: Cell::new(Duration::from_secs(0)),
979 decode_def_path_tables_time: Cell::new(Duration::from_secs(0)),
981 code_stats: RefCell::new(CodeStats::new()),
982 optimization_fuel_crate,
983 optimization_fuel_limit,
986 out_of_fuel: Cell::new(false),
987 // Note that this is unsafe because it may misinterpret file descriptors
988 // on Unix as jobserver file descriptors. We hopefully execute this near
989 // the beginning of the process though to ensure we don't get false
990 // positives, or in other words we try to execute this before we open
991 // any file descriptors ourselves.
993 // Also note that we stick this in a global because there could be
994 // multiple `Session` instances in this process, and the jobserver is
996 jobserver_from_env: unsafe {
997 static mut GLOBAL_JOBSERVER: *mut Option<Client> = 0 as *mut _;
998 static INIT: Once = ONCE_INIT;
1000 GLOBAL_JOBSERVER = Box::into_raw(Box::new(Client::from_env()));
1002 (*GLOBAL_JOBSERVER).clone()
1004 has_global_allocator: Cell::new(false),
1010 /// Hash value constructed out of all the `-C metadata` arguments passed to the
1011 /// compiler. Together with the crate-name forms a unique global identifier for
1013 #[derive(Eq, PartialEq, Ord, PartialOrd, Hash, Debug, Clone, Copy, RustcEncodable, RustcDecodable)]
1014 pub struct CrateDisambiguator(Fingerprint);
1016 impl CrateDisambiguator {
1017 pub fn to_fingerprint(self) -> Fingerprint {
1022 impl From<Fingerprint> for CrateDisambiguator {
1023 fn from(fingerprint: Fingerprint) -> CrateDisambiguator {
1024 CrateDisambiguator(fingerprint)
1028 impl_stable_hash_for!(tuple_struct CrateDisambiguator { fingerprint });
1030 /// Holds data on the current incremental compilation session, if there is one.
1032 pub enum IncrCompSession {
1033 /// This is the state the session will be in until the incr. comp. dir is
1036 /// This is the state during which the session directory is private and can
1039 session_directory: PathBuf,
1040 lock_file: flock::Lock,
1041 load_dep_graph: bool,
1043 /// This is the state after the session directory has been finalized. In this
1044 /// state, the contents of the directory must not be modified any more.
1046 session_directory: PathBuf,
1048 /// This is an error state that is reached when some compilation error has
1049 /// occurred. It indicates that the contents of the session directory must
1050 /// not be used, since they might be invalid.
1051 InvalidBecauseOfErrors {
1052 session_directory: PathBuf,
1056 pub fn early_error(output: config::ErrorOutputType, msg: &str) -> ! {
1057 let emitter: Box<Emitter> = match output {
1058 config::ErrorOutputType::HumanReadable(color_config) => {
1059 Box::new(EmitterWriter::stderr(color_config, None, false))
1061 config::ErrorOutputType::Json(pretty) => Box::new(JsonEmitter::basic(pretty)),
1062 config::ErrorOutputType::Short(color_config) => {
1063 Box::new(EmitterWriter::stderr(color_config, None, true))
1066 let handler = errors::Handler::with_emitter(true, false, emitter);
1067 handler.emit(&MultiSpan::new(), msg, errors::Level::Fatal);
1068 panic!(errors::FatalError);
1071 pub fn early_warn(output: config::ErrorOutputType, msg: &str) {
1072 let emitter: Box<Emitter> = match output {
1073 config::ErrorOutputType::HumanReadable(color_config) => {
1074 Box::new(EmitterWriter::stderr(color_config, None, false))
1076 config::ErrorOutputType::Json(pretty) => Box::new(JsonEmitter::basic(pretty)),
1077 config::ErrorOutputType::Short(color_config) => {
1078 Box::new(EmitterWriter::stderr(color_config, None, true))
1081 let handler = errors::Handler::with_emitter(true, false, emitter);
1082 handler.emit(&MultiSpan::new(), msg, errors::Level::Warning);
1085 #[derive(Copy, Clone, Debug)]
1086 pub enum CompileIncomplete {
1088 Errored(ErrorReported)
1090 impl From<ErrorReported> for CompileIncomplete {
1091 fn from(err: ErrorReported) -> CompileIncomplete {
1092 CompileIncomplete::Errored(err)
1095 pub type CompileResult = Result<(), CompileIncomplete>;
1097 pub fn compile_result_from_err_count(err_count: usize) -> CompileResult {
1101 Err(CompileIncomplete::Errored(ErrorReported))
1107 pub fn bug_fmt(file: &'static str, line: u32, args: fmt::Arguments) -> ! {
1108 // this wrapper mostly exists so I don't have to write a fully
1109 // qualified path of None::<Span> inside the bug!() macro definition
1110 opt_span_bug_fmt(file, line, None::<Span>, args);
1115 pub fn span_bug_fmt<S: Into<MultiSpan>>(file: &'static str,
1118 args: fmt::Arguments) -> ! {
1119 opt_span_bug_fmt(file, line, Some(span), args);
1122 fn opt_span_bug_fmt<S: Into<MultiSpan>>(file: &'static str,
1125 args: fmt::Arguments) -> ! {
1126 tls::with_opt(move |tcx| {
1127 let msg = format!("{}:{}: {}", file, line, args);
1129 (Some(tcx), Some(span)) => tcx.sess.diagnostic().span_bug(span, &msg),
1130 (Some(tcx), None) => tcx.sess.diagnostic().bug(&msg),
1131 (None, _) => panic!(msg)