1 use crate::cgu_reuse_tracker::CguReuseTracker;
2 use crate::code_stats::CodeStats;
3 pub use crate::code_stats::{DataTypeKind, FieldInfo, SizeKind, VariantInfo};
4 use crate::config::{self, CrateType, InstrumentCoverage, OptLevel, OutputType, SwitchWithOptPath};
6 CannotEnableCrtStaticLinux, CannotMixAndMatchSanitizers, LinkerPluginToWindowsNotSupported,
7 NotCircumventFeature, ProfileSampleUseFileDoesNotExist, ProfileUseFileDoesNotExist,
8 SanitizerCfiEnabled, SanitizerNotSupported, SanitizersNotSupported,
9 SplitDebugInfoUnstablePlatform, StackProtectorNotSupportedForTarget,
10 TargetRequiresUnwindTables, UnstableVirtualFunctionElimination, UnsupportedDwarfVersion,
12 use crate::parse::{add_feature_diagnostics, ParseSess};
13 use crate::search_paths::{PathKind, SearchPath};
14 use crate::{filesearch, lint};
16 pub use rustc_ast::attr::MarkedAttrs;
17 pub use rustc_ast::Attribute;
18 use rustc_data_structures::flock;
19 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
20 use rustc_data_structures::jobserver::{self, Client};
21 use rustc_data_structures::profiling::{duration_to_secs_str, SelfProfiler, SelfProfilerRef};
22 use rustc_data_structures::sync::{
23 self, AtomicU64, AtomicUsize, Lock, Lrc, OnceCell, OneThread, Ordering, Ordering::SeqCst,
25 use rustc_errors::annotate_snippet_emitter_writer::AnnotateSnippetEmitterWriter;
26 use rustc_errors::emitter::{Emitter, EmitterWriter, HumanReadableErrorType};
27 use rustc_errors::json::JsonEmitter;
28 use rustc_errors::registry::Registry;
30 error_code, fallback_fluent_bundle, DiagnosticBuilder, DiagnosticId, DiagnosticMessage,
31 ErrorGuaranteed, FluentBundle, IntoDiagnostic, LazyFallbackBundle, MultiSpan, Noted,
33 use rustc_macros::HashStable_Generic;
34 pub use rustc_span::def_id::StableCrateId;
35 use rustc_span::edition::Edition;
36 use rustc_span::source_map::{FileLoader, RealFileLoader, SourceMap, Span};
37 use rustc_span::{sym, SourceFileHashAlgorithm, Symbol};
38 use rustc_target::asm::InlineAsmArch;
39 use rustc_target::spec::{CodeModel, PanicStrategy, RelocModel, RelroLevel};
40 use rustc_target::spec::{
41 DebuginfoKind, SanitizerSet, SplitDebuginfo, StackProtector, Target, TargetTriple, TlsModel,
44 use std::cell::{self, RefCell};
47 use std::ops::{Div, Mul};
48 use std::path::{Path, PathBuf};
49 use std::str::FromStr;
51 use std::time::Duration;
53 pub struct OptimizationFuel {
54 /// If `-zfuel=crate=n` is specified, initially set to `n`, otherwise `0`.
56 /// We're rejecting all further optimizations.
60 /// The behavior of the CTFE engine when an error occurs with regards to backtraces.
61 #[derive(Clone, Copy)]
62 pub enum CtfeBacktrace {
63 /// Do nothing special, return the error as usual without a backtrace.
65 /// Capture a backtrace at the point the error is created and return it in the error
66 /// (to be printed later if/when the error ever actually gets shown to the user).
68 /// Capture a backtrace at the point the error is created and immediately print it out.
72 /// New-type wrapper around `usize` for representing limits. Ensures that comparisons against
73 /// limits are consistent throughout the compiler.
74 #[derive(Clone, Copy, Debug, HashStable_Generic)]
75 pub struct Limit(pub usize);
78 /// Create a new limit from a `usize`.
79 pub fn new(value: usize) -> Self {
83 /// Check that `value` is within the limit. Ensures that the same comparisons are used
84 /// throughout the compiler, as mismatches can cause ICEs, see #72540.
86 pub fn value_within_limit(&self, value: usize) -> bool {
91 impl From<usize> for Limit {
92 fn from(value: usize) -> Self {
97 impl fmt::Display for Limit {
98 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
103 impl Div<usize> for Limit {
106 fn div(self, rhs: usize) -> Self::Output {
107 Limit::new(self.0 / rhs)
111 impl Mul<usize> for Limit {
114 fn mul(self, rhs: usize) -> Self::Output {
115 Limit::new(self.0 * rhs)
119 impl rustc_errors::IntoDiagnosticArg for Limit {
120 fn into_diagnostic_arg(self) -> rustc_errors::DiagnosticArgValue<'static> {
121 self.to_string().into_diagnostic_arg()
125 #[derive(Clone, Copy, Debug, HashStable_Generic)]
127 /// The maximum recursion limit for potentially infinitely recursive
128 /// operations such as auto-dereference and monomorphization.
129 pub recursion_limit: Limit,
130 /// The size at which the `large_assignments` lint starts
132 pub move_size_limit: Limit,
133 /// The maximum length of types during monomorphization.
134 pub type_length_limit: Limit,
135 /// The maximum blocks a const expression can evaluate.
136 pub const_eval_limit: Limit,
139 /// Represents the data associated with a compilation
140 /// session for a single crate.
144 pub opts: config::Options,
145 pub host_tlib_path: Lrc<SearchPath>,
146 pub target_tlib_path: Lrc<SearchPath>,
147 pub parse_sess: ParseSess,
148 pub sysroot: PathBuf,
149 /// The name of the root source file of the crate, in the local file system.
150 /// `None` means that there is no source file.
151 pub local_crate_source_file: Option<PathBuf>,
153 crate_types: OnceCell<Vec<CrateType>>,
154 /// The `stable_crate_id` is constructed out of the crate name and all the
155 /// `-C metadata` arguments passed to the compiler. Its value forms a unique
156 /// global identifier for the crate. It is used to allow multiple crates
157 /// with the same name to coexist. See the
158 /// `rustc_codegen_llvm::back::symbol_names` module for more information.
159 pub stable_crate_id: OnceCell<StableCrateId>,
161 features: OnceCell<rustc_feature::Features>,
163 incr_comp_session: OneThread<RefCell<IncrCompSession>>,
164 /// Used for incremental compilation tests. Will only be populated if
165 /// `-Zquery-dep-graph` is specified.
166 pub cgu_reuse_tracker: CguReuseTracker,
168 /// Used by `-Z self-profile`.
169 pub prof: SelfProfilerRef,
171 /// Some measurements that are being gathered during compilation.
172 pub perf_stats: PerfStats,
174 /// Data about code being compiled, gathered during compilation.
175 pub code_stats: CodeStats,
177 /// Tracks fuel info if `-zfuel=crate=n` is specified.
178 optimization_fuel: Lock<OptimizationFuel>,
180 /// Always set to zero and incremented so that we can print fuel expended by a crate.
181 pub print_fuel: AtomicU64,
183 /// Loaded up early on in the initialization of this `Session` to avoid
184 /// false positives about a job server in our environment.
185 pub jobserver: Client,
187 /// Cap lint level specified by a driver specifically.
188 pub driver_lint_caps: FxHashMap<lint::LintId, lint::Level>,
190 /// Tracks the current behavior of the CTFE engine when an error occurs.
191 /// Options range from returning the error without a backtrace to returning an error
192 /// and immediately printing the backtrace to stderr.
193 /// The `Lock` is only used by miri to allow setting `ctfe_backtrace` after analysis when
194 /// `MIRI_BACKTRACE` is set. This makes it only apply to miri's errors and not to all CTFE
196 pub ctfe_backtrace: Lock<CtfeBacktrace>,
198 /// This tracks where `-Zunleash-the-miri-inside-of-you` was used to get around a
199 /// const check, optionally with the relevant feature gate. We use this to
200 /// warn about unleashing, but with a single diagnostic instead of dozens that
201 /// drown everything else in noise.
202 miri_unleashed_features: Lock<Vec<(Span, Option<Symbol>)>>,
204 /// Architecture to use for interpreting asm!.
205 pub asm_arch: Option<InlineAsmArch>,
207 /// Set of enabled features for the current target.
208 pub target_features: FxHashSet<Symbol>,
210 /// Set of enabled features for the current target, including unstable ones.
211 pub unstable_target_features: FxHashSet<Symbol>,
214 pub struct PerfStats {
215 /// The accumulated time spent on computing symbol hashes.
216 pub symbol_hash_time: Lock<Duration>,
217 /// Total number of values canonicalized queries constructed.
218 pub queries_canonicalized: AtomicUsize,
219 /// Number of times this query is invoked.
220 pub normalize_generic_arg_after_erasing_regions: AtomicUsize,
221 /// Number of times this query is invoked.
222 pub normalize_projection_ty: AtomicUsize,
226 pub fn miri_unleashed_feature(&self, span: Span, feature_gate: Option<Symbol>) {
227 self.miri_unleashed_features.lock().push((span, feature_gate));
230 fn check_miri_unleashed_features(&self) {
231 let unleashed_features = self.miri_unleashed_features.lock();
232 if !unleashed_features.is_empty() {
233 let mut must_err = false;
234 // Create a diagnostic pointing at where things got unleashed.
235 // FIXME(#100717): needs eager translation/lists
236 #[allow(rustc::untranslatable_diagnostic)]
237 #[allow(rustc::diagnostic_outside_of_impl)]
238 let mut diag = self.struct_warn("skipping const checks");
239 for &(span, feature_gate) in unleashed_features.iter() {
240 // FIXME: `span_label` doesn't do anything, so we use "help" as a hack.
241 if let Some(gate) = feature_gate {
242 diag.span_help(span, &format!("skipping check for `{gate}` feature"));
243 // The unleash flag must *not* be used to just "hack around" feature gates.
246 diag.span_help(span, "skipping check that does not even have a feature gate");
250 // If we should err, make sure we did.
251 if must_err && self.has_errors().is_none() {
252 // We have skipped a feature gate, and not run into other errors... reject.
253 self.emit_err(NotCircumventFeature);
258 /// Invoked all the way at the end to finish off diagnostics printing.
259 pub fn finish_diagnostics(&self, registry: &Registry) {
260 self.check_miri_unleashed_features();
261 self.diagnostic().print_error_count(registry);
262 self.emit_future_breakage();
265 fn emit_future_breakage(&self) {
266 if !self.opts.json_future_incompat {
270 let diags = self.diagnostic().take_future_breakage_diagnostics();
271 if diags.is_empty() {
274 self.parse_sess.span_diagnostic.emit_future_breakage_report(diags);
277 pub fn local_stable_crate_id(&self) -> StableCrateId {
278 self.stable_crate_id.get().copied().unwrap()
281 pub fn crate_types(&self) -> &[CrateType] {
282 self.crate_types.get().unwrap().as_slice()
285 pub fn init_crate_types(&self, crate_types: Vec<CrateType>) {
286 self.crate_types.set(crate_types).expect("`crate_types` was initialized twice")
289 #[rustc_lint_diagnostics]
291 pub fn struct_span_warn<S: Into<MultiSpan>>(
294 msg: impl Into<DiagnosticMessage>,
295 ) -> DiagnosticBuilder<'_, ()> {
296 self.diagnostic().struct_span_warn(sp, msg)
298 #[rustc_lint_diagnostics]
300 pub fn struct_span_warn_with_expectation<S: Into<MultiSpan>>(
303 msg: impl Into<DiagnosticMessage>,
304 id: lint::LintExpectationId,
305 ) -> DiagnosticBuilder<'_, ()> {
306 self.diagnostic().struct_span_warn_with_expectation(sp, msg, id)
308 #[rustc_lint_diagnostics]
310 pub fn struct_span_warn_with_code<S: Into<MultiSpan>>(
313 msg: impl Into<DiagnosticMessage>,
315 ) -> DiagnosticBuilder<'_, ()> {
316 self.diagnostic().struct_span_warn_with_code(sp, msg, code)
318 #[rustc_lint_diagnostics]
320 pub fn struct_warn(&self, msg: impl Into<DiagnosticMessage>) -> DiagnosticBuilder<'_, ()> {
321 self.diagnostic().struct_warn(msg)
323 #[rustc_lint_diagnostics]
325 pub fn struct_warn_with_expectation(
327 msg: impl Into<DiagnosticMessage>,
328 id: lint::LintExpectationId,
329 ) -> DiagnosticBuilder<'_, ()> {
330 self.diagnostic().struct_warn_with_expectation(msg, id)
332 #[rustc_lint_diagnostics]
333 pub fn struct_span_allow<S: Into<MultiSpan>>(
336 msg: impl Into<DiagnosticMessage>,
337 ) -> DiagnosticBuilder<'_, ()> {
338 self.diagnostic().struct_span_allow(sp, msg)
340 #[rustc_lint_diagnostics]
341 pub fn struct_allow(&self, msg: impl Into<DiagnosticMessage>) -> DiagnosticBuilder<'_, ()> {
342 self.diagnostic().struct_allow(msg)
344 #[rustc_lint_diagnostics]
345 pub fn struct_expect(
347 msg: impl Into<DiagnosticMessage>,
348 id: lint::LintExpectationId,
349 ) -> DiagnosticBuilder<'_, ()> {
350 self.diagnostic().struct_expect(msg, id)
352 #[rustc_lint_diagnostics]
354 pub fn struct_span_err<S: Into<MultiSpan>>(
357 msg: impl Into<DiagnosticMessage>,
358 ) -> DiagnosticBuilder<'_, ErrorGuaranteed> {
359 self.diagnostic().struct_span_err(sp, msg)
361 #[rustc_lint_diagnostics]
363 pub fn struct_span_err_with_code<S: Into<MultiSpan>>(
366 msg: impl Into<DiagnosticMessage>,
368 ) -> DiagnosticBuilder<'_, ErrorGuaranteed> {
369 self.diagnostic().struct_span_err_with_code(sp, msg, code)
371 // FIXME: This method should be removed (every error should have an associated error code).
372 #[rustc_lint_diagnostics]
376 msg: impl Into<DiagnosticMessage>,
377 ) -> DiagnosticBuilder<'_, ErrorGuaranteed> {
378 self.parse_sess.struct_err(msg)
381 #[rustc_lint_diagnostics]
382 pub fn struct_err_with_code(
384 msg: impl Into<DiagnosticMessage>,
386 ) -> DiagnosticBuilder<'_, ErrorGuaranteed> {
387 self.diagnostic().struct_err_with_code(msg, code)
389 #[rustc_lint_diagnostics]
391 pub fn struct_warn_with_code(
393 msg: impl Into<DiagnosticMessage>,
395 ) -> DiagnosticBuilder<'_, ()> {
396 self.diagnostic().struct_warn_with_code(msg, code)
398 #[rustc_lint_diagnostics]
399 pub fn struct_span_fatal<S: Into<MultiSpan>>(
402 msg: impl Into<DiagnosticMessage>,
403 ) -> DiagnosticBuilder<'_, !> {
404 self.diagnostic().struct_span_fatal(sp, msg)
406 #[rustc_lint_diagnostics]
407 pub fn struct_span_fatal_with_code<S: Into<MultiSpan>>(
410 msg: impl Into<DiagnosticMessage>,
412 ) -> DiagnosticBuilder<'_, !> {
413 self.diagnostic().struct_span_fatal_with_code(sp, msg, code)
415 #[rustc_lint_diagnostics]
416 pub fn struct_fatal(&self, msg: impl Into<DiagnosticMessage>) -> DiagnosticBuilder<'_, !> {
417 self.diagnostic().struct_fatal(msg)
420 #[rustc_lint_diagnostics]
421 pub fn span_fatal<S: Into<MultiSpan>>(&self, sp: S, msg: impl Into<DiagnosticMessage>) -> ! {
422 self.diagnostic().span_fatal(sp, msg)
424 #[rustc_lint_diagnostics]
425 pub fn span_fatal_with_code<S: Into<MultiSpan>>(
428 msg: impl Into<DiagnosticMessage>,
431 self.diagnostic().span_fatal_with_code(sp, msg, code)
433 #[rustc_lint_diagnostics]
434 pub fn fatal(&self, msg: impl Into<DiagnosticMessage>) -> ! {
435 self.diagnostic().fatal(msg).raise()
437 #[rustc_lint_diagnostics]
439 pub fn span_err_or_warn<S: Into<MultiSpan>>(
443 msg: impl Into<DiagnosticMessage>,
446 self.span_warn(sp, msg);
448 self.span_err(sp, msg);
451 #[rustc_lint_diagnostics]
453 pub fn span_err<S: Into<MultiSpan>>(
456 msg: impl Into<DiagnosticMessage>,
457 ) -> ErrorGuaranteed {
458 self.diagnostic().span_err(sp, msg)
460 #[rustc_lint_diagnostics]
461 pub fn span_err_with_code<S: Into<MultiSpan>>(
464 msg: impl Into<DiagnosticMessage>,
467 self.diagnostic().span_err_with_code(sp, msg, code)
469 #[rustc_lint_diagnostics]
470 pub fn err(&self, msg: impl Into<DiagnosticMessage>) -> ErrorGuaranteed {
471 self.diagnostic().err(msg)
474 pub fn create_err<'a>(
476 err: impl IntoDiagnostic<'a>,
477 ) -> DiagnosticBuilder<'a, ErrorGuaranteed> {
478 self.parse_sess.create_err(err)
481 pub fn create_feature_err<'a>(
483 err: impl IntoDiagnostic<'a>,
485 ) -> DiagnosticBuilder<'a, ErrorGuaranteed> {
486 let mut err = self.parse_sess.create_err(err);
487 if err.code.is_none() {
488 err.code = std::option::Option::Some(error_code!(E0658));
490 add_feature_diagnostics(&mut err, &self.parse_sess, feature);
493 pub fn emit_err<'a>(&'a self, err: impl IntoDiagnostic<'a>) -> ErrorGuaranteed {
494 self.parse_sess.emit_err(err)
496 pub fn create_warning<'a>(
498 err: impl IntoDiagnostic<'a, ()>,
499 ) -> DiagnosticBuilder<'a, ()> {
500 self.parse_sess.create_warning(err)
502 pub fn emit_warning<'a>(&'a self, warning: impl IntoDiagnostic<'a, ()>) {
503 self.parse_sess.emit_warning(warning)
505 pub fn create_note<'a>(
507 note: impl IntoDiagnostic<'a, Noted>,
508 ) -> DiagnosticBuilder<'a, Noted> {
509 self.parse_sess.create_note(note)
511 pub fn emit_note<'a>(&'a self, note: impl IntoDiagnostic<'a, Noted>) -> Noted {
512 self.parse_sess.emit_note(note)
514 pub fn create_fatal<'a>(
516 fatal: impl IntoDiagnostic<'a, !>,
517 ) -> DiagnosticBuilder<'a, !> {
518 self.parse_sess.create_fatal(fatal)
520 pub fn emit_fatal<'a>(&'a self, fatal: impl IntoDiagnostic<'a, !>) -> ! {
521 self.parse_sess.emit_fatal(fatal)
524 pub fn err_count(&self) -> usize {
525 self.diagnostic().err_count()
527 pub fn has_errors(&self) -> Option<ErrorGuaranteed> {
528 self.diagnostic().has_errors()
530 pub fn has_errors_or_delayed_span_bugs(&self) -> bool {
531 self.diagnostic().has_errors_or_delayed_span_bugs()
533 pub fn abort_if_errors(&self) {
534 self.diagnostic().abort_if_errors();
536 pub fn compile_status(&self) -> Result<(), ErrorGuaranteed> {
537 if let Some(reported) = self.diagnostic().has_errors_or_lint_errors() {
538 let _ = self.diagnostic().emit_stashed_diagnostics();
544 // FIXME(matthewjasper) Remove this method, it should never be needed.
545 pub fn track_errors<F, T>(&self, f: F) -> Result<T, ErrorGuaranteed>
549 let old_count = self.err_count();
551 if self.err_count() == old_count {
554 Err(ErrorGuaranteed::unchecked_claim_error_was_emitted())
557 #[allow(rustc::untranslatable_diagnostic)]
558 #[allow(rustc::diagnostic_outside_of_impl)]
559 pub fn span_warn<S: Into<MultiSpan>>(&self, sp: S, msg: impl Into<DiagnosticMessage>) {
560 self.diagnostic().span_warn(sp, msg)
562 #[allow(rustc::untranslatable_diagnostic)]
563 #[allow(rustc::diagnostic_outside_of_impl)]
564 pub fn span_warn_with_code<S: Into<MultiSpan>>(
567 msg: impl Into<DiagnosticMessage>,
570 self.diagnostic().span_warn_with_code(sp, msg, code)
572 pub fn warn(&self, msg: impl Into<DiagnosticMessage>) {
573 self.diagnostic().warn(msg)
575 /// Delay a span_bug() call until abort_if_errors()
577 pub fn delay_span_bug<S: Into<MultiSpan>>(
580 msg: impl Into<DiagnosticMessage>,
581 ) -> ErrorGuaranteed {
582 self.diagnostic().delay_span_bug(sp, msg)
585 /// Used for code paths of expensive computations that should only take place when
586 /// warnings or errors are emitted. If no messages are emitted ("good path"), then
587 /// it's likely a bug.
588 pub fn delay_good_path_bug(&self, msg: impl Into<DiagnosticMessage>) {
589 if self.opts.unstable_opts.print_type_sizes
590 || self.opts.unstable_opts.query_dep_graph
591 || self.opts.unstable_opts.dump_mir.is_some()
592 || self.opts.unstable_opts.unpretty.is_some()
593 || self.opts.output_types.contains_key(&OutputType::Mir)
594 || std::env::var_os("RUSTC_LOG").is_some()
599 self.diagnostic().delay_good_path_bug(msg)
602 pub fn note_without_error(&self, msg: impl Into<DiagnosticMessage>) {
603 self.diagnostic().note_without_error(msg)
605 pub fn span_note_without_error<S: Into<MultiSpan>>(
608 msg: impl Into<DiagnosticMessage>,
610 self.diagnostic().span_note_without_error(sp, msg)
612 #[allow(rustc::untranslatable_diagnostic)]
613 #[allow(rustc::diagnostic_outside_of_impl)]
614 pub fn struct_note_without_error(
616 msg: impl Into<DiagnosticMessage>,
617 ) -> DiagnosticBuilder<'_, ()> {
618 self.diagnostic().struct_note_without_error(msg)
622 pub fn diagnostic(&self) -> &rustc_errors::Handler {
623 &self.parse_sess.span_diagnostic
627 pub fn source_map(&self) -> &SourceMap {
628 self.parse_sess.source_map()
631 /// Returns `true` if internal lints should be added to the lint store - i.e. if
632 /// `-Zunstable-options` is provided and this isn't rustdoc (internal lints can trigger errors
633 /// to be emitted under rustdoc).
634 pub fn enable_internal_lints(&self) -> bool {
635 self.unstable_options() && !self.opts.actually_rustdoc
638 pub fn instrument_coverage(&self) -> bool {
639 self.opts.cg.instrument_coverage() != InstrumentCoverage::Off
642 pub fn instrument_coverage_except_unused_generics(&self) -> bool {
643 self.opts.cg.instrument_coverage() == InstrumentCoverage::ExceptUnusedGenerics
646 pub fn instrument_coverage_except_unused_functions(&self) -> bool {
647 self.opts.cg.instrument_coverage() == InstrumentCoverage::ExceptUnusedFunctions
650 /// Gets the features enabled for the current compilation session.
651 /// DO NOT USE THIS METHOD if there is a TyCtxt available, as it circumvents
652 /// dependency tracking. Use tcx.features() instead.
654 pub fn features_untracked(&self) -> &rustc_feature::Features {
655 self.features.get().unwrap()
658 pub fn init_features(&self, features: rustc_feature::Features) {
659 match self.features.set(features) {
661 Err(_) => panic!("`features` was initialized twice"),
665 pub fn is_sanitizer_cfi_enabled(&self) -> bool {
666 self.opts.unstable_opts.sanitizer.contains(SanitizerSet::CFI)
669 /// Check whether this compile session and crate type use static crt.
670 pub fn crt_static(&self, crate_type: Option<CrateType>) -> bool {
671 if !self.target.crt_static_respected {
672 // If the target does not opt in to crt-static support, use its default.
673 return self.target.crt_static_default;
676 let requested_features = self.opts.cg.target_feature.split(',');
677 let found_negative = requested_features.clone().any(|r| r == "-crt-static");
678 let found_positive = requested_features.clone().any(|r| r == "+crt-static");
680 // JUSTIFICATION: necessary use of crate_types directly (see FIXME below)
681 #[allow(rustc::bad_opt_access)]
682 if found_positive || found_negative {
684 } else if crate_type == Some(CrateType::ProcMacro)
685 || crate_type == None && self.opts.crate_types.contains(&CrateType::ProcMacro)
687 // FIXME: When crate_type is not available,
688 // we use compiler options to determine the crate_type.
689 // We can't check `#![crate_type = "proc-macro"]` here.
692 self.target.crt_static_default
696 pub fn is_wasi_reactor(&self) -> bool {
697 self.target.options.os == "wasi"
699 self.opts.unstable_opts.wasi_exec_model,
700 Some(config::WasiExecModel::Reactor)
704 /// Returns `true` if the target can use the current split debuginfo configuration.
705 pub fn target_can_use_split_dwarf(&self) -> bool {
706 self.target.debuginfo_kind == DebuginfoKind::Dwarf
709 pub fn generate_proc_macro_decls_symbol(&self, stable_crate_id: StableCrateId) -> String {
710 format!("__rustc_proc_macro_decls_{:08x}__", stable_crate_id.to_u64())
713 pub fn target_filesearch(&self, kind: PathKind) -> filesearch::FileSearch<'_> {
714 filesearch::FileSearch::new(
716 self.opts.target_triple.triple(),
717 &self.opts.search_paths,
718 &self.target_tlib_path,
722 pub fn host_filesearch(&self, kind: PathKind) -> filesearch::FileSearch<'_> {
723 filesearch::FileSearch::new(
725 config::host_triple(),
726 &self.opts.search_paths,
727 &self.host_tlib_path,
732 /// Returns a list of directories where target-specific tool binaries are located.
733 pub fn get_tools_search_paths(&self, self_contained: bool) -> Vec<PathBuf> {
734 let rustlib_path = rustc_target::target_rustlib_path(&self.sysroot, &config::host_triple());
735 let p = PathBuf::from_iter([
736 Path::new(&self.sysroot),
737 Path::new(&rustlib_path),
740 if self_contained { vec![p.clone(), p.join("self-contained")] } else { vec![p] }
743 pub fn init_incr_comp_session(
745 session_dir: PathBuf,
746 lock_file: flock::Lock,
747 load_dep_graph: bool,
749 let mut incr_comp_session = self.incr_comp_session.borrow_mut();
751 if let IncrCompSession::NotInitialized = *incr_comp_session {
753 panic!("Trying to initialize IncrCompSession `{:?}`", *incr_comp_session)
757 IncrCompSession::Active { session_directory: session_dir, lock_file, load_dep_graph };
760 pub fn finalize_incr_comp_session(&self, new_directory_path: PathBuf) {
761 let mut incr_comp_session = self.incr_comp_session.borrow_mut();
763 if let IncrCompSession::Active { .. } = *incr_comp_session {
765 panic!("trying to finalize `IncrCompSession` `{:?}`", *incr_comp_session);
768 // Note: this will also drop the lock file, thus unlocking the directory.
769 *incr_comp_session = IncrCompSession::Finalized { session_directory: new_directory_path };
772 pub fn mark_incr_comp_session_as_invalid(&self) {
773 let mut incr_comp_session = self.incr_comp_session.borrow_mut();
775 let session_directory = match *incr_comp_session {
776 IncrCompSession::Active { ref session_directory, .. } => session_directory.clone(),
777 IncrCompSession::InvalidBecauseOfErrors { .. } => return,
778 _ => panic!("trying to invalidate `IncrCompSession` `{:?}`", *incr_comp_session),
781 // Note: this will also drop the lock file, thus unlocking the directory.
782 *incr_comp_session = IncrCompSession::InvalidBecauseOfErrors { session_directory };
785 pub fn incr_comp_session_dir(&self) -> cell::Ref<'_, PathBuf> {
786 let incr_comp_session = self.incr_comp_session.borrow();
787 cell::Ref::map(incr_comp_session, |incr_comp_session| match *incr_comp_session {
788 IncrCompSession::NotInitialized => panic!(
789 "trying to get session directory from `IncrCompSession`: {:?}",
792 IncrCompSession::Active { ref session_directory, .. }
793 | IncrCompSession::Finalized { ref session_directory }
794 | IncrCompSession::InvalidBecauseOfErrors { ref session_directory } => {
800 pub fn incr_comp_session_dir_opt(&self) -> Option<cell::Ref<'_, PathBuf>> {
801 self.opts.incremental.as_ref().map(|_| self.incr_comp_session_dir())
804 pub fn print_perf_stats(&self) {
806 "Total time spent computing symbol hashes: {}",
807 duration_to_secs_str(*self.perf_stats.symbol_hash_time.lock())
810 "Total queries canonicalized: {}",
811 self.perf_stats.queries_canonicalized.load(Ordering::Relaxed)
814 "normalize_generic_arg_after_erasing_regions: {}",
815 self.perf_stats.normalize_generic_arg_after_erasing_regions.load(Ordering::Relaxed)
818 "normalize_projection_ty: {}",
819 self.perf_stats.normalize_projection_ty.load(Ordering::Relaxed)
823 /// We want to know if we're allowed to do an optimization for crate foo from -z fuel=foo=n.
824 /// This expends fuel if applicable, and records fuel if applicable.
825 pub fn consider_optimizing<T: Fn() -> String>(&self, crate_name: &str, msg: T) -> bool {
827 if let Some((ref c, _)) = self.opts.unstable_opts.fuel {
829 assert_eq!(self.threads(), 1);
830 let mut fuel = self.optimization_fuel.lock();
831 ret = fuel.remaining != 0;
832 if fuel.remaining == 0 && !fuel.out_of_fuel {
833 if self.diagnostic().can_emit_warnings() {
834 // We only call `msg` in case we can actually emit warnings.
835 // Otherwise, this could cause a `delay_good_path_bug` to
836 // trigger (issue #79546).
837 self.warn(&format!("optimization-fuel-exhausted: {}", msg()));
839 fuel.out_of_fuel = true;
840 } else if fuel.remaining > 0 {
845 if let Some(ref c) = self.opts.unstable_opts.print_fuel {
847 assert_eq!(self.threads(), 1);
848 self.print_fuel.fetch_add(1, SeqCst);
854 pub fn rust_2015(&self) -> bool {
855 self.edition() == Edition::Edition2015
858 /// Are we allowed to use features from the Rust 2018 edition?
859 pub fn rust_2018(&self) -> bool {
860 self.edition() >= Edition::Edition2018
863 /// Are we allowed to use features from the Rust 2021 edition?
864 pub fn rust_2021(&self) -> bool {
865 self.edition() >= Edition::Edition2021
868 /// Are we allowed to use features from the Rust 2024 edition?
869 pub fn rust_2024(&self) -> bool {
870 self.edition() >= Edition::Edition2024
873 /// Returns `true` if we cannot skip the PLT for shared library calls.
874 pub fn needs_plt(&self) -> bool {
875 // Check if the current target usually needs PLT to be enabled.
876 // The user can use the command line flag to override it.
877 let needs_plt = self.target.needs_plt;
879 let dbg_opts = &self.opts.unstable_opts;
881 let relro_level = dbg_opts.relro_level.unwrap_or(self.target.relro_level);
883 // Only enable this optimization by default if full relro is also enabled.
884 // In this case, lazy binding was already unavailable, so nothing is lost.
885 // This also ensures `-Wl,-z,now` is supported by the linker.
886 let full_relro = RelroLevel::Full == relro_level;
888 // If user didn't explicitly forced us to use / skip the PLT,
889 // then try to skip it where possible.
890 dbg_opts.plt.unwrap_or(needs_plt || !full_relro)
893 /// Checks if LLVM lifetime markers should be emitted.
894 pub fn emit_lifetime_markers(&self) -> bool {
895 self.opts.optimize != config::OptLevel::No
896 // AddressSanitizer uses lifetimes to detect use after scope bugs.
897 // MemorySanitizer uses lifetimes to detect use of uninitialized stack variables.
898 // HWAddressSanitizer will use lifetimes to detect use after scope bugs in the future.
899 || self.opts.unstable_opts.sanitizer.intersects(SanitizerSet::ADDRESS | SanitizerSet::MEMORY | SanitizerSet::HWADDRESS)
902 pub fn is_proc_macro_attr(&self, attr: &Attribute) -> bool {
903 [sym::proc_macro, sym::proc_macro_attribute, sym::proc_macro_derive]
905 .any(|kind| attr.has_name(*kind))
908 pub fn contains_name(&self, attrs: &[Attribute], name: Symbol) -> bool {
909 attrs.iter().any(|item| item.has_name(name))
912 pub fn find_by_name<'a>(
914 attrs: &'a [Attribute],
916 ) -> Option<&'a Attribute> {
917 attrs.iter().find(|attr| attr.has_name(name))
920 pub fn filter_by_name<'a>(
922 attrs: &'a [Attribute],
924 ) -> impl Iterator<Item = &'a Attribute> {
925 attrs.iter().filter(move |attr| attr.has_name(name))
928 pub fn first_attr_value_str_by_name(
932 ) -> Option<Symbol> {
933 attrs.iter().find(|at| at.has_name(name)).and_then(|at| at.value_str())
937 // JUSTIFICATION: defn of the suggested wrapper fns
938 #[allow(rustc::bad_opt_access)]
940 pub fn verbose(&self) -> bool {
941 self.opts.unstable_opts.verbose
944 pub fn instrument_mcount(&self) -> bool {
945 self.opts.unstable_opts.instrument_mcount
948 pub fn time_passes(&self) -> bool {
949 self.opts.unstable_opts.time_passes
952 pub fn time_llvm_passes(&self) -> bool {
953 self.opts.unstable_opts.time_llvm_passes
956 pub fn meta_stats(&self) -> bool {
957 self.opts.unstable_opts.meta_stats
960 pub fn asm_comments(&self) -> bool {
961 self.opts.unstable_opts.asm_comments
964 pub fn verify_llvm_ir(&self) -> bool {
965 self.opts.unstable_opts.verify_llvm_ir || option_env!("RUSTC_VERIFY_LLVM_IR").is_some()
968 pub fn print_llvm_passes(&self) -> bool {
969 self.opts.unstable_opts.print_llvm_passes
972 pub fn binary_dep_depinfo(&self) -> bool {
973 self.opts.unstable_opts.binary_dep_depinfo
976 pub fn mir_opt_level(&self) -> usize {
980 .unwrap_or_else(|| if self.opts.optimize != OptLevel::No { 2 } else { 1 })
983 /// Calculates the flavor of LTO to use for this compilation.
984 pub fn lto(&self) -> config::Lto {
985 // If our target has codegen requirements ignore the command line
986 if self.target.requires_lto {
987 return config::Lto::Fat;
990 // If the user specified something, return that. If they only said `-C
991 // lto` and we've for whatever reason forced off ThinLTO via the CLI,
992 // then ensure we can't use a ThinLTO.
993 match self.opts.cg.lto {
994 config::LtoCli::Unspecified => {
995 // The compiler was invoked without the `-Clto` flag. Fall
996 // through to the default handling
998 config::LtoCli::No => {
999 // The user explicitly opted out of any kind of LTO
1000 return config::Lto::No;
1002 config::LtoCli::Yes | config::LtoCli::Fat | config::LtoCli::NoParam => {
1003 // All of these mean fat LTO
1004 return config::Lto::Fat;
1006 config::LtoCli::Thin => {
1007 return if self.opts.cli_forced_thinlto_off {
1015 // Ok at this point the target doesn't require anything and the user
1016 // hasn't asked for anything. Our next decision is whether or not
1017 // we enable "auto" ThinLTO where we use multiple codegen units and
1018 // then do ThinLTO over those codegen units. The logic below will
1019 // either return `No` or `ThinLocal`.
1021 // If processing command line options determined that we're incompatible
1022 // with ThinLTO (e.g., `-C lto --emit llvm-ir`) then return that option.
1023 if self.opts.cli_forced_thinlto_off {
1024 return config::Lto::No;
1027 // If `-Z thinlto` specified process that, but note that this is mostly
1028 // a deprecated option now that `-C lto=thin` exists.
1029 if let Some(enabled) = self.opts.unstable_opts.thinlto {
1031 return config::Lto::ThinLocal;
1033 return config::Lto::No;
1037 // If there's only one codegen unit and LTO isn't enabled then there's
1038 // no need for ThinLTO so just return false.
1039 if self.codegen_units() == 1 {
1040 return config::Lto::No;
1043 // Now we're in "defaults" territory. By default we enable ThinLTO for
1044 // optimized compiles (anything greater than O0).
1045 match self.opts.optimize {
1046 config::OptLevel::No => config::Lto::No,
1047 _ => config::Lto::ThinLocal,
1051 /// Returns the panic strategy for this compile session. If the user explicitly selected one
1052 /// using '-C panic', use that, otherwise use the panic strategy defined by the target.
1053 pub fn panic_strategy(&self) -> PanicStrategy {
1054 self.opts.cg.panic.unwrap_or(self.target.panic_strategy)
1057 pub fn fewer_names(&self) -> bool {
1058 if let Some(fewer_names) = self.opts.unstable_opts.fewer_names {
1061 let more_names = self.opts.output_types.contains_key(&OutputType::LlvmAssembly)
1062 || self.opts.output_types.contains_key(&OutputType::Bitcode)
1063 // AddressSanitizer and MemorySanitizer use alloca name when reporting an issue.
1064 || self.opts.unstable_opts.sanitizer.intersects(SanitizerSet::ADDRESS | SanitizerSet::MEMORY);
1069 pub fn unstable_options(&self) -> bool {
1070 self.opts.unstable_opts.unstable_options
1073 pub fn is_nightly_build(&self) -> bool {
1074 self.opts.unstable_features.is_nightly_build()
1077 pub fn overflow_checks(&self) -> bool {
1078 self.opts.cg.overflow_checks.unwrap_or(self.opts.debug_assertions)
1081 pub fn relocation_model(&self) -> RelocModel {
1082 self.opts.cg.relocation_model.unwrap_or(self.target.relocation_model)
1085 pub fn code_model(&self) -> Option<CodeModel> {
1086 self.opts.cg.code_model.or(self.target.code_model)
1089 pub fn tls_model(&self) -> TlsModel {
1090 self.opts.unstable_opts.tls_model.unwrap_or(self.target.tls_model)
1093 pub fn split_debuginfo(&self) -> SplitDebuginfo {
1094 self.opts.cg.split_debuginfo.unwrap_or(self.target.split_debuginfo)
1097 pub fn stack_protector(&self) -> StackProtector {
1098 if self.target.options.supports_stack_protector {
1099 self.opts.unstable_opts.stack_protector
1101 StackProtector::None
1105 pub fn must_emit_unwind_tables(&self) -> bool {
1106 // This is used to control the emission of the `uwtable` attribute on
1109 // Unwind tables are needed when compiling with `-C panic=unwind`, but
1110 // LLVM won't omit unwind tables unless the function is also marked as
1111 // `nounwind`, so users are allowed to disable `uwtable` emission.
1112 // Historically rustc always emits `uwtable` attributes by default, so
1113 // even they can be disabled, they're still emitted by default.
1115 // On some targets (including windows), however, exceptions include
1116 // other events such as illegal instructions, segfaults, etc. This means
1117 // that on Windows we end up still needing unwind tables even if the `-C
1118 // panic=abort` flag is passed.
1120 // You can also find more info on why Windows needs unwind tables in:
1121 // https://bugzilla.mozilla.org/show_bug.cgi?id=1302078
1123 // If a target requires unwind tables, then they must be emitted.
1124 // Otherwise, we can defer to the `-C force-unwind-tables=<yes/no>`
1125 // value, if it is provided, or disable them, if not.
1126 self.target.requires_uwtable
1127 || self.opts.cg.force_unwind_tables.unwrap_or(
1128 self.panic_strategy() == PanicStrategy::Unwind || self.target.default_uwtable,
1132 /// Returns the number of query threads that should be used for this
1134 pub fn threads(&self) -> usize {
1135 self.opts.unstable_opts.threads
1138 /// Returns the number of codegen units that should be used for this
1140 pub fn codegen_units(&self) -> usize {
1141 if let Some(n) = self.opts.cli_forced_codegen_units {
1144 if let Some(n) = self.target.default_codegen_units {
1148 // If incremental compilation is turned on, we default to a high number
1149 // codegen units in order to reduce the "collateral damage" small
1151 if self.opts.incremental.is_some() {
1155 // Why is 16 codegen units the default all the time?
1157 // The main reason for enabling multiple codegen units by default is to
1158 // leverage the ability for the codegen backend to do codegen and
1159 // optimization in parallel. This allows us, especially for large crates, to
1160 // make good use of all available resources on the machine once we've
1161 // hit that stage of compilation. Large crates especially then often
1162 // take a long time in codegen/optimization and this helps us amortize that
1165 // Note that a high number here doesn't mean that we'll be spawning a
1166 // large number of threads in parallel. The backend of rustc contains
1167 // global rate limiting through the `jobserver` crate so we'll never
1168 // overload the system with too much work, but rather we'll only be
1169 // optimizing when we're otherwise cooperating with other instances of
1172 // Rather a high number here means that we should be able to keep a lot
1173 // of idle cpus busy. By ensuring that no codegen unit takes *too* long
1174 // to build we'll be guaranteed that all cpus will finish pretty closely
1175 // to one another and we should make relatively optimal use of system
1178 // Note that the main cost of codegen units is that it prevents LLVM
1179 // from inlining across codegen units. Users in general don't have a lot
1180 // of control over how codegen units are split up so it's our job in the
1181 // compiler to ensure that undue performance isn't lost when using
1182 // codegen units (aka we can't require everyone to slap `#[inline]` on
1185 // If we're compiling at `-O0` then the number doesn't really matter too
1186 // much because performance doesn't matter and inlining is ok to lose.
1187 // In debug mode we just want to try to guarantee that no cpu is stuck
1188 // doing work that could otherwise be farmed to others.
1190 // In release mode, however (O1 and above) performance does indeed
1191 // matter! To recover the loss in performance due to inlining we'll be
1192 // enabling ThinLTO by default (the function for which is just below).
1193 // This will ensure that we recover any inlining wins we otherwise lost
1194 // through codegen unit partitioning.
1198 // Ok that's a lot of words but the basic tl;dr; is that we want a high
1199 // number here -- but not too high. Additionally we're "safe" to have it
1200 // always at the same number at all optimization levels.
1202 // As a result 16 was chosen here! Mostly because it was a power of 2
1203 // and most benchmarks agreed it was roughly a local optimum. Not very
1208 pub fn teach(&self, code: &DiagnosticId) -> bool {
1209 self.opts.unstable_opts.teach && self.diagnostic().must_teach(code)
1212 pub fn edition(&self) -> Edition {
1216 pub fn link_dead_code(&self) -> bool {
1217 self.opts.cg.link_dead_code.unwrap_or(false)
1221 // JUSTIFICATION: part of session construction
1222 #[allow(rustc::bad_opt_access)]
1224 sopts: &config::Options,
1225 registry: rustc_errors::registry::Registry,
1226 source_map: Lrc<SourceMap>,
1227 bundle: Option<Lrc<FluentBundle>>,
1228 fallback_bundle: LazyFallbackBundle,
1229 ) -> Box<dyn Emitter + sync::Send> {
1230 let macro_backtrace = sopts.unstable_opts.macro_backtrace;
1231 let track_diagnostics = sopts.unstable_opts.track_diagnostics;
1232 match sopts.error_format {
1233 config::ErrorOutputType::HumanReadable(kind) => {
1234 let (short, color_config) = kind.unzip();
1236 if let HumanReadableErrorType::AnnotateSnippet(_) = kind {
1237 let emitter = AnnotateSnippetEmitterWriter::new(
1244 Box::new(emitter.ui_testing(sopts.unstable_opts.ui_testing))
1246 let emitter = EmitterWriter::stderr(
1252 sopts.unstable_opts.teach,
1253 sopts.diagnostic_width,
1257 Box::new(emitter.ui_testing(sopts.unstable_opts.ui_testing))
1260 config::ErrorOutputType::Json { pretty, json_rendered } => Box::new(
1261 JsonEmitter::stderr(
1268 sopts.diagnostic_width,
1272 .ui_testing(sopts.unstable_opts.ui_testing),
1277 // JUSTIFICATION: literally session construction
1278 #[allow(rustc::bad_opt_access)]
1279 pub fn build_session(
1280 sopts: config::Options,
1281 local_crate_source_file: Option<PathBuf>,
1282 bundle: Option<Lrc<rustc_errors::FluentBundle>>,
1283 registry: rustc_errors::registry::Registry,
1284 driver_lint_caps: FxHashMap<lint::LintId, lint::Level>,
1285 file_loader: Option<Box<dyn FileLoader + Send + Sync + 'static>>,
1286 target_override: Option<Target>,
1288 // FIXME: This is not general enough to make the warning lint completely override
1289 // normal diagnostic warnings, since the warning lint can also be denied and changed
1290 // later via the source code.
1291 let warnings_allow = sopts
1294 .rfind(|&&(ref key, _)| *key == "warnings")
1295 .map_or(false, |&(_, level)| level == lint::Allow);
1296 let cap_lints_allow = sopts.lint_cap.map_or(false, |cap| cap == lint::Allow);
1297 let can_emit_warnings = !(warnings_allow || cap_lints_allow);
1299 let sysroot = match &sopts.maybe_sysroot {
1300 Some(sysroot) => sysroot.clone(),
1301 None => filesearch::get_or_default_sysroot(),
1304 let target_cfg = config::build_target_config(&sopts, target_override, &sysroot);
1305 let host_triple = TargetTriple::from_triple(config::host_triple());
1306 let (host, target_warnings) = Target::search(&host_triple, &sysroot).unwrap_or_else(|e| {
1307 early_error(sopts.error_format, &format!("Error loading host specification: {e}"))
1309 for warning in target_warnings.warning_messages() {
1310 early_warn(sopts.error_format, &warning)
1313 let loader = file_loader.unwrap_or_else(|| Box::new(RealFileLoader));
1314 let hash_kind = sopts.unstable_opts.src_hash_algorithm.unwrap_or_else(|| {
1315 if target_cfg.is_like_msvc {
1316 SourceFileHashAlgorithm::Sha1
1318 SourceFileHashAlgorithm::Md5
1321 let source_map = Lrc::new(SourceMap::with_file_loader_and_hash_kind(
1323 sopts.file_path_mapping(),
1327 let fallback_bundle = fallback_fluent_bundle(
1328 rustc_errors::DEFAULT_LOCALE_RESOURCES,
1329 sopts.unstable_opts.translate_directionality_markers,
1331 let emitter = default_emitter(&sopts, registry, source_map.clone(), bundle, fallback_bundle);
1333 let span_diagnostic = rustc_errors::Handler::with_emitter_and_flags(
1335 sopts.unstable_opts.diagnostic_handler_flags(can_emit_warnings),
1338 let self_profiler = if let SwitchWithOptPath::Enabled(ref d) = sopts.unstable_opts.self_profile
1341 if let Some(ref directory) = d { directory } else { std::path::Path::new(".") };
1343 let profiler = SelfProfiler::new(
1345 sopts.crate_name.as_deref(),
1346 sopts.unstable_opts.self_profile_events.as_ref().map(|xs| &xs[..]),
1347 &sopts.unstable_opts.self_profile_counter,
1350 Ok(profiler) => Some(Arc::new(profiler)),
1352 early_warn(sopts.error_format, &format!("failed to create profiler: {e}"));
1360 let mut parse_sess = ParseSess::with_span_handler(span_diagnostic, source_map);
1361 parse_sess.assume_incomplete_release = sopts.unstable_opts.assume_incomplete_release;
1363 let host_triple = config::host_triple();
1364 let target_triple = sopts.target_triple.triple();
1365 let host_tlib_path = Lrc::new(SearchPath::from_sysroot_and_triple(&sysroot, host_triple));
1366 let target_tlib_path = if host_triple == target_triple {
1367 // Use the same `SearchPath` if host and target triple are identical to avoid unnecessary
1368 // rescanning of the target lib path and an unnecessary allocation.
1369 host_tlib_path.clone()
1371 Lrc::new(SearchPath::from_sysroot_and_triple(&sysroot, target_triple))
1374 let file_path_mapping = sopts.file_path_mapping();
1376 let local_crate_source_file =
1377 local_crate_source_file.map(|path| file_path_mapping.map_prefix(path).0);
1379 let optimization_fuel = Lock::new(OptimizationFuel {
1380 remaining: sopts.unstable_opts.fuel.as_ref().map_or(0, |i| i.1),
1383 let print_fuel = AtomicU64::new(0);
1385 let cgu_reuse_tracker = if sopts.unstable_opts.query_dep_graph {
1386 CguReuseTracker::new()
1388 CguReuseTracker::new_disabled()
1391 let prof = SelfProfilerRef::new(self_profiler, sopts.unstable_opts.time_passes);
1393 let ctfe_backtrace = Lock::new(match env::var("RUSTC_CTFE_BACKTRACE") {
1394 Ok(ref val) if val == "immediate" => CtfeBacktrace::Immediate,
1395 Ok(ref val) if val != "0" => CtfeBacktrace::Capture,
1396 _ => CtfeBacktrace::Disabled,
1400 if target_cfg.allow_asm { InlineAsmArch::from_str(&target_cfg.arch).ok() } else { None };
1402 let sess = Session {
1410 local_crate_source_file,
1411 crate_types: OnceCell::new(),
1412 stable_crate_id: OnceCell::new(),
1413 features: OnceCell::new(),
1414 incr_comp_session: OneThread::new(RefCell::new(IncrCompSession::NotInitialized)),
1417 perf_stats: PerfStats {
1418 symbol_hash_time: Lock::new(Duration::from_secs(0)),
1419 queries_canonicalized: AtomicUsize::new(0),
1420 normalize_generic_arg_after_erasing_regions: AtomicUsize::new(0),
1421 normalize_projection_ty: AtomicUsize::new(0),
1423 code_stats: Default::default(),
1426 jobserver: jobserver::client(),
1429 miri_unleashed_features: Lock::new(Default::default()),
1431 target_features: FxHashSet::default(),
1432 unstable_target_features: FxHashSet::default(),
1435 validate_commandline_args_with_session_available(&sess);
1440 /// Validate command line arguments with a `Session`.
1442 /// If it is useful to have a Session available already for validating a commandline argument, you
1444 // JUSTIFICATION: needs to access args to validate them
1445 #[allow(rustc::bad_opt_access)]
1446 fn validate_commandline_args_with_session_available(sess: &Session) {
1447 // Since we don't know if code in an rlib will be linked to statically or
1448 // dynamically downstream, rustc generates `__imp_` symbols that help linkers
1449 // on Windows deal with this lack of knowledge (#27438). Unfortunately,
1450 // these manually generated symbols confuse LLD when it tries to merge
1451 // bitcode during ThinLTO. Therefore we disallow dynamic linking on Windows
1452 // when compiling for LLD ThinLTO. This way we can validly just not generate
1453 // the `dllimport` attributes and `__imp_` symbols in that case.
1454 if sess.opts.cg.linker_plugin_lto.enabled()
1455 && sess.opts.cg.prefer_dynamic
1456 && sess.target.is_like_windows
1458 sess.emit_err(LinkerPluginToWindowsNotSupported);
1461 // Make sure that any given profiling data actually exists so LLVM can't
1462 // decide to silently skip PGO.
1463 if let Some(ref path) = sess.opts.cg.profile_use {
1465 sess.emit_err(ProfileUseFileDoesNotExist { path });
1469 // Do the same for sample profile data.
1470 if let Some(ref path) = sess.opts.unstable_opts.profile_sample_use {
1472 sess.emit_err(ProfileSampleUseFileDoesNotExist { path });
1476 // Unwind tables cannot be disabled if the target requires them.
1477 if let Some(include_uwtables) = sess.opts.cg.force_unwind_tables {
1478 if sess.target.requires_uwtable && !include_uwtables {
1479 sess.emit_err(TargetRequiresUnwindTables);
1483 // Sanitizers can only be used on platforms that we know have working sanitizer codegen.
1484 let supported_sanitizers = sess.target.options.supported_sanitizers;
1485 let unsupported_sanitizers = sess.opts.unstable_opts.sanitizer - supported_sanitizers;
1486 match unsupported_sanitizers.into_iter().count() {
1489 sess.emit_err(SanitizerNotSupported { us: unsupported_sanitizers.to_string() });
1492 sess.emit_err(SanitizersNotSupported { us: unsupported_sanitizers.to_string() });
1495 // Cannot mix and match sanitizers.
1496 let mut sanitizer_iter = sess.opts.unstable_opts.sanitizer.into_iter();
1497 if let (Some(first), Some(second)) = (sanitizer_iter.next(), sanitizer_iter.next()) {
1498 sess.emit_err(CannotMixAndMatchSanitizers {
1499 first: first.to_string(),
1500 second: second.to_string(),
1504 // Cannot enable crt-static with sanitizers on Linux
1505 if sess.crt_static(None) && !sess.opts.unstable_opts.sanitizer.is_empty() {
1506 sess.emit_err(CannotEnableCrtStaticLinux);
1509 // LLVM CFI and VFE both require LTO.
1510 if sess.lto() != config::Lto::Fat {
1511 if sess.is_sanitizer_cfi_enabled() {
1512 sess.emit_err(SanitizerCfiEnabled);
1514 if sess.opts.unstable_opts.virtual_function_elimination {
1515 sess.emit_err(UnstableVirtualFunctionElimination);
1519 if sess.opts.unstable_opts.stack_protector != StackProtector::None {
1520 if !sess.target.options.supports_stack_protector {
1521 sess.emit_warning(StackProtectorNotSupportedForTarget {
1522 stack_protector: sess.opts.unstable_opts.stack_protector,
1523 target_triple: &sess.opts.target_triple,
1528 if let Some(dwarf_version) = sess.opts.unstable_opts.dwarf_version {
1529 if dwarf_version > 5 {
1530 sess.emit_err(UnsupportedDwarfVersion { dwarf_version });
1534 if !sess.target.options.supported_split_debuginfo.contains(&sess.split_debuginfo())
1535 && !sess.opts.unstable_opts.unstable_options
1537 sess.emit_err(SplitDebugInfoUnstablePlatform { debuginfo: sess.split_debuginfo() });
1541 /// Holds data on the current incremental compilation session, if there is one.
1543 pub enum IncrCompSession {
1544 /// This is the state the session will be in until the incr. comp. dir is
1547 /// This is the state during which the session directory is private and can
1549 Active { session_directory: PathBuf, lock_file: flock::Lock, load_dep_graph: bool },
1550 /// This is the state after the session directory has been finalized. In this
1551 /// state, the contents of the directory must not be modified any more.
1552 Finalized { session_directory: PathBuf },
1553 /// This is an error state that is reached when some compilation error has
1554 /// occurred. It indicates that the contents of the session directory must
1555 /// not be used, since they might be invalid.
1556 InvalidBecauseOfErrors { session_directory: PathBuf },
1559 fn early_error_handler(output: config::ErrorOutputType) -> rustc_errors::Handler {
1560 let fallback_bundle = fallback_fluent_bundle(rustc_errors::DEFAULT_LOCALE_RESOURCES, false);
1561 let emitter: Box<dyn Emitter + sync::Send> = match output {
1562 config::ErrorOutputType::HumanReadable(kind) => {
1563 let (short, color_config) = kind.unzip();
1564 Box::new(EmitterWriter::stderr(
1576 config::ErrorOutputType::Json { pretty, json_rendered } => Box::new(JsonEmitter::basic(
1586 rustc_errors::Handler::with_emitter(true, None, emitter)
1589 #[allow(rustc::untranslatable_diagnostic)]
1590 #[allow(rustc::diagnostic_outside_of_impl)]
1591 pub fn early_error_no_abort(output: config::ErrorOutputType, msg: &str) -> ErrorGuaranteed {
1592 early_error_handler(output).struct_err(msg).emit()
1595 #[allow(rustc::untranslatable_diagnostic)]
1596 #[allow(rustc::diagnostic_outside_of_impl)]
1597 pub fn early_error(output: config::ErrorOutputType, msg: &str) -> ! {
1598 early_error_handler(output).struct_fatal(msg).emit()
1601 #[allow(rustc::untranslatable_diagnostic)]
1602 #[allow(rustc::diagnostic_outside_of_impl)]
1603 pub fn early_warn(output: config::ErrorOutputType, msg: &str) {
1604 early_error_handler(output).struct_warn(msg).emit()