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, OutputType, SwitchWithOptPath};
5 use crate::parse::ParseSess;
6 use crate::search_paths::{PathKind, SearchPath};
7 use crate::{filesearch, lint};
9 pub use rustc_ast::attr::MarkedAttrs;
10 pub use rustc_ast::Attribute;
11 use rustc_data_structures::flock;
12 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
13 use rustc_data_structures::jobserver::{self, Client};
14 use rustc_data_structures::profiling::{duration_to_secs_str, SelfProfiler, SelfProfilerRef};
15 use rustc_data_structures::sync::{
16 self, AtomicU64, AtomicUsize, Lock, Lrc, OnceCell, OneThread, Ordering, Ordering::SeqCst,
18 use rustc_errors::annotate_snippet_emitter_writer::AnnotateSnippetEmitterWriter;
19 use rustc_errors::emitter::{Emitter, EmitterWriter, HumanReadableErrorType};
20 use rustc_errors::json::JsonEmitter;
21 use rustc_errors::registry::Registry;
23 fallback_fluent_bundle, DiagnosticBuilder, DiagnosticId, DiagnosticMessage, EmissionGuarantee,
24 ErrorGuaranteed, FluentBundle, LazyFallbackBundle, MultiSpan,
26 use rustc_macros::HashStable_Generic;
27 pub use rustc_span::def_id::StableCrateId;
28 use rustc_span::edition::Edition;
29 use rustc_span::source_map::{FileLoader, RealFileLoader, SourceMap, Span};
30 use rustc_span::{sym, SourceFileHashAlgorithm, Symbol};
31 use rustc_target::asm::InlineAsmArch;
32 use rustc_target::spec::{CodeModel, PanicStrategy, RelocModel, RelroLevel};
33 use rustc_target::spec::{
34 SanitizerSet, SplitDebuginfo, StackProtector, Target, TargetTriple, TlsModel,
37 use std::cell::{self, RefCell};
41 use std::ops::{Div, Mul};
42 use std::path::{Path, PathBuf};
43 use std::str::FromStr;
45 use std::time::Duration;
47 pub struct OptimizationFuel {
48 /// If `-zfuel=crate=n` is specified, initially set to `n`, otherwise `0`.
50 /// We're rejecting all further optimizations.
54 /// The behavior of the CTFE engine when an error occurs with regards to backtraces.
55 #[derive(Clone, Copy)]
56 pub enum CtfeBacktrace {
57 /// Do nothing special, return the error as usual without a backtrace.
59 /// Capture a backtrace at the point the error is created and return it in the error
60 /// (to be printed later if/when the error ever actually gets shown to the user).
62 /// Capture a backtrace at the point the error is created and immediately print it out.
66 /// New-type wrapper around `usize` for representing limits. Ensures that comparisons against
67 /// limits are consistent throughout the compiler.
68 #[derive(Clone, Copy, Debug, HashStable_Generic)]
69 pub struct Limit(pub usize);
72 /// Create a new limit from a `usize`.
73 pub fn new(value: usize) -> Self {
77 /// Check that `value` is within the limit. Ensures that the same comparisons are used
78 /// throughout the compiler, as mismatches can cause ICEs, see #72540.
80 pub fn value_within_limit(&self, value: usize) -> bool {
85 impl From<usize> for Limit {
86 fn from(value: usize) -> Self {
91 impl fmt::Display for Limit {
92 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
97 impl Div<usize> for Limit {
100 fn div(self, rhs: usize) -> Self::Output {
101 Limit::new(self.0 / rhs)
105 impl Mul<usize> for Limit {
108 fn mul(self, rhs: usize) -> Self::Output {
109 Limit::new(self.0 * rhs)
113 #[derive(Clone, Copy, Debug, HashStable_Generic)]
115 /// The maximum recursion limit for potentially infinitely recursive
116 /// operations such as auto-dereference and monomorphization.
117 pub recursion_limit: Limit,
118 /// The size at which the `large_assignments` lint starts
120 pub move_size_limit: Limit,
121 /// The maximum length of types during monomorphization.
122 pub type_length_limit: Limit,
123 /// The maximum blocks a const expression can evaluate.
124 pub const_eval_limit: Limit,
127 /// Represents the data associated with a compilation
128 /// session for a single crate.
132 pub opts: config::Options,
133 pub host_tlib_path: Lrc<SearchPath>,
134 pub target_tlib_path: Lrc<SearchPath>,
135 pub parse_sess: ParseSess,
136 pub sysroot: PathBuf,
137 /// The name of the root source file of the crate, in the local file system.
138 /// `None` means that there is no source file.
139 pub local_crate_source_file: Option<PathBuf>,
141 crate_types: OnceCell<Vec<CrateType>>,
142 /// The `stable_crate_id` is constructed out of the crate name and all the
143 /// `-C metadata` arguments passed to the compiler. Its value forms a unique
144 /// global identifier for the crate. It is used to allow multiple crates
145 /// with the same name to coexist. See the
146 /// `rustc_codegen_llvm::back::symbol_names` module for more information.
147 pub stable_crate_id: OnceCell<StableCrateId>,
149 features: OnceCell<rustc_feature::Features>,
151 incr_comp_session: OneThread<RefCell<IncrCompSession>>,
152 /// Used for incremental compilation tests. Will only be populated if
153 /// `-Zquery-dep-graph` is specified.
154 pub cgu_reuse_tracker: CguReuseTracker,
156 /// Used by `-Z self-profile`.
157 pub prof: SelfProfilerRef,
159 /// Some measurements that are being gathered during compilation.
160 pub perf_stats: PerfStats,
162 /// Data about code being compiled, gathered during compilation.
163 pub code_stats: CodeStats,
165 /// Tracks fuel info if `-zfuel=crate=n` is specified.
166 optimization_fuel: Lock<OptimizationFuel>,
168 /// Always set to zero and incremented so that we can print fuel expended by a crate.
169 pub print_fuel: AtomicU64,
171 /// Loaded up early on in the initialization of this `Session` to avoid
172 /// false positives about a job server in our environment.
173 pub jobserver: Client,
175 /// Cap lint level specified by a driver specifically.
176 pub driver_lint_caps: FxHashMap<lint::LintId, lint::Level>,
178 /// Tracks the current behavior of the CTFE engine when an error occurs.
179 /// Options range from returning the error without a backtrace to returning an error
180 /// and immediately printing the backtrace to stderr.
181 /// The `Lock` is only used by miri to allow setting `ctfe_backtrace` after analysis when
182 /// `MIRI_BACKTRACE` is set. This makes it only apply to miri's errors and not to all CTFE
184 pub ctfe_backtrace: Lock<CtfeBacktrace>,
186 /// This tracks where `-Zunleash-the-miri-inside-of-you` was used to get around a
187 /// const check, optionally with the relevant feature gate. We use this to
188 /// warn about unleashing, but with a single diagnostic instead of dozens that
189 /// drown everything else in noise.
190 miri_unleashed_features: Lock<Vec<(Span, Option<Symbol>)>>,
192 /// Architecture to use for interpreting asm!.
193 pub asm_arch: Option<InlineAsmArch>,
195 /// Set of enabled features for the current target.
196 pub target_features: FxHashSet<Symbol>,
199 pub struct PerfStats {
200 /// The accumulated time spent on computing symbol hashes.
201 pub symbol_hash_time: Lock<Duration>,
202 /// Total number of values canonicalized queries constructed.
203 pub queries_canonicalized: AtomicUsize,
204 /// Number of times this query is invoked.
205 pub normalize_generic_arg_after_erasing_regions: AtomicUsize,
206 /// Number of times this query is invoked.
207 pub normalize_projection_ty: AtomicUsize,
210 /// Trait implemented by error types. This should not be implemented manually. Instead, use
211 /// `#[derive(SessionDiagnostic)]` -- see [rustc_macros::SessionDiagnostic].
212 #[rustc_diagnostic_item = "SessionDiagnostic"]
213 pub trait SessionDiagnostic<'a, T: EmissionGuarantee = ErrorGuaranteed> {
214 /// Write out as a diagnostic out of `sess`.
216 fn into_diagnostic(self, sess: &'a ParseSess) -> DiagnosticBuilder<'a, T>;
220 pub fn miri_unleashed_feature(&self, span: Span, feature_gate: Option<Symbol>) {
221 self.miri_unleashed_features.lock().push((span, feature_gate));
224 fn check_miri_unleashed_features(&self) {
225 let unleashed_features = self.miri_unleashed_features.lock();
226 if !unleashed_features.is_empty() {
227 let mut must_err = false;
228 // Create a diagnostic pointing at where things got unleashed.
229 let mut diag = self.struct_warn("skipping const checks");
230 for &(span, feature_gate) in unleashed_features.iter() {
231 // FIXME: `span_label` doesn't do anything, so we use "help" as a hack.
232 if let Some(gate) = feature_gate {
233 diag.span_help(span, &format!("skipping check for `{gate}` feature"));
234 // The unleash flag must *not* be used to just "hack around" feature gates.
237 diag.span_help(span, "skipping check that does not even have a feature gate");
241 // If we should err, make sure we did.
242 if must_err && self.has_errors().is_none() {
243 // We have skipped a feature gate, and not run into other errors... reject.
245 "`-Zunleash-the-miri-inside-of-you` may not be used to circumvent feature \
246 gates, except when testing error paths in the CTFE engine",
252 /// Invoked all the way at the end to finish off diagnostics printing.
253 pub fn finish_diagnostics(&self, registry: &Registry) {
254 self.check_miri_unleashed_features();
255 self.diagnostic().print_error_count(registry);
256 self.emit_future_breakage();
259 fn emit_future_breakage(&self) {
260 if !self.opts.json_future_incompat {
264 let diags = self.diagnostic().take_future_breakage_diagnostics();
265 if diags.is_empty() {
268 self.parse_sess.span_diagnostic.emit_future_breakage_report(diags);
271 pub fn local_stable_crate_id(&self) -> StableCrateId {
272 self.stable_crate_id.get().copied().unwrap()
275 pub fn crate_types(&self) -> &[CrateType] {
276 self.crate_types.get().unwrap().as_slice()
279 pub fn init_crate_types(&self, crate_types: Vec<CrateType>) {
280 self.crate_types.set(crate_types).expect("`crate_types` was initialized twice")
283 #[rustc_lint_diagnostics]
284 pub fn struct_span_warn<S: Into<MultiSpan>>(
287 msg: impl Into<DiagnosticMessage>,
288 ) -> DiagnosticBuilder<'_, ()> {
289 self.diagnostic().struct_span_warn(sp, msg)
291 #[rustc_lint_diagnostics]
292 pub fn struct_span_warn_with_expectation<S: Into<MultiSpan>>(
295 msg: impl Into<DiagnosticMessage>,
296 id: lint::LintExpectationId,
297 ) -> DiagnosticBuilder<'_, ()> {
298 self.diagnostic().struct_span_warn_with_expectation(sp, msg, id)
300 #[rustc_lint_diagnostics]
301 pub fn struct_span_warn_with_code<S: Into<MultiSpan>>(
304 msg: impl Into<DiagnosticMessage>,
306 ) -> DiagnosticBuilder<'_, ()> {
307 self.diagnostic().struct_span_warn_with_code(sp, msg, code)
309 #[rustc_lint_diagnostics]
310 pub fn struct_warn(&self, msg: impl Into<DiagnosticMessage>) -> DiagnosticBuilder<'_, ()> {
311 self.diagnostic().struct_warn(msg)
313 #[rustc_lint_diagnostics]
314 pub fn struct_warn_with_expectation(
316 msg: impl Into<DiagnosticMessage>,
317 id: lint::LintExpectationId,
318 ) -> DiagnosticBuilder<'_, ()> {
319 self.diagnostic().struct_warn_with_expectation(msg, id)
321 #[rustc_lint_diagnostics]
322 pub fn struct_span_allow<S: Into<MultiSpan>>(
325 msg: impl Into<DiagnosticMessage>,
326 ) -> DiagnosticBuilder<'_, ()> {
327 self.diagnostic().struct_span_allow(sp, msg)
329 #[rustc_lint_diagnostics]
330 pub fn struct_allow(&self, msg: impl Into<DiagnosticMessage>) -> DiagnosticBuilder<'_, ()> {
331 self.diagnostic().struct_allow(msg)
333 #[rustc_lint_diagnostics]
334 pub fn struct_expect(
336 msg: impl Into<DiagnosticMessage>,
337 id: lint::LintExpectationId,
338 ) -> DiagnosticBuilder<'_, ()> {
339 self.diagnostic().struct_expect(msg, id)
341 #[rustc_lint_diagnostics]
342 pub fn struct_span_err<S: Into<MultiSpan>>(
345 msg: impl Into<DiagnosticMessage>,
346 ) -> DiagnosticBuilder<'_, ErrorGuaranteed> {
347 self.diagnostic().struct_span_err(sp, msg)
349 #[rustc_lint_diagnostics]
350 pub fn struct_span_err_with_code<S: Into<MultiSpan>>(
353 msg: impl Into<DiagnosticMessage>,
355 ) -> DiagnosticBuilder<'_, ErrorGuaranteed> {
356 self.diagnostic().struct_span_err_with_code(sp, msg, code)
358 // FIXME: This method should be removed (every error should have an associated error code).
359 #[rustc_lint_diagnostics]
362 msg: impl Into<DiagnosticMessage>,
363 ) -> DiagnosticBuilder<'_, ErrorGuaranteed> {
364 self.parse_sess.struct_err(msg)
366 #[rustc_lint_diagnostics]
367 pub fn struct_err_with_code(
369 msg: impl Into<DiagnosticMessage>,
371 ) -> DiagnosticBuilder<'_, ErrorGuaranteed> {
372 self.diagnostic().struct_err_with_code(msg, code)
374 #[rustc_lint_diagnostics]
375 pub fn struct_warn_with_code(
377 msg: impl Into<DiagnosticMessage>,
379 ) -> DiagnosticBuilder<'_, ()> {
380 self.diagnostic().struct_warn_with_code(msg, code)
382 #[rustc_lint_diagnostics]
383 pub fn struct_span_fatal<S: Into<MultiSpan>>(
386 msg: impl Into<DiagnosticMessage>,
387 ) -> DiagnosticBuilder<'_, !> {
388 self.diagnostic().struct_span_fatal(sp, msg)
390 #[rustc_lint_diagnostics]
391 pub fn struct_span_fatal_with_code<S: Into<MultiSpan>>(
394 msg: impl Into<DiagnosticMessage>,
396 ) -> DiagnosticBuilder<'_, !> {
397 self.diagnostic().struct_span_fatal_with_code(sp, msg, code)
399 #[rustc_lint_diagnostics]
400 pub fn struct_fatal(&self, msg: impl Into<DiagnosticMessage>) -> DiagnosticBuilder<'_, !> {
401 self.diagnostic().struct_fatal(msg)
404 #[rustc_lint_diagnostics]
405 pub fn span_fatal<S: Into<MultiSpan>>(&self, sp: S, msg: impl Into<DiagnosticMessage>) -> ! {
406 self.diagnostic().span_fatal(sp, msg)
408 #[rustc_lint_diagnostics]
409 pub fn span_fatal_with_code<S: Into<MultiSpan>>(
412 msg: impl Into<DiagnosticMessage>,
415 self.diagnostic().span_fatal_with_code(sp, msg, code)
417 #[rustc_lint_diagnostics]
418 pub fn fatal(&self, msg: impl Into<DiagnosticMessage>) -> ! {
419 self.diagnostic().fatal(msg).raise()
421 #[rustc_lint_diagnostics]
422 pub fn span_err_or_warn<S: Into<MultiSpan>>(
426 msg: impl Into<DiagnosticMessage>,
429 self.span_warn(sp, msg);
431 self.span_err(sp, msg);
434 #[rustc_lint_diagnostics]
435 pub fn span_err<S: Into<MultiSpan>>(
438 msg: impl Into<DiagnosticMessage>,
439 ) -> ErrorGuaranteed {
440 self.diagnostic().span_err(sp, msg)
442 #[rustc_lint_diagnostics]
443 pub fn span_err_with_code<S: Into<MultiSpan>>(
446 msg: impl Into<DiagnosticMessage>,
449 self.diagnostic().span_err_with_code(sp, msg, code)
451 #[rustc_lint_diagnostics]
452 pub fn err(&self, msg: impl Into<DiagnosticMessage>) -> ErrorGuaranteed {
453 self.diagnostic().err(msg)
455 pub fn create_err<'a>(
457 err: impl SessionDiagnostic<'a>,
458 ) -> DiagnosticBuilder<'a, ErrorGuaranteed> {
459 self.parse_sess.create_err(err)
461 pub fn emit_err<'a>(&'a self, err: impl SessionDiagnostic<'a>) -> ErrorGuaranteed {
462 self.parse_sess.emit_err(err)
464 pub fn create_warning<'a>(
466 err: impl SessionDiagnostic<'a, ()>,
467 ) -> DiagnosticBuilder<'a, ()> {
468 self.parse_sess.create_warning(err)
470 pub fn emit_warning<'a>(&'a self, warning: impl SessionDiagnostic<'a, ()>) {
471 self.parse_sess.emit_warning(warning)
474 pub fn err_count(&self) -> usize {
475 self.diagnostic().err_count()
477 pub fn has_errors(&self) -> Option<ErrorGuaranteed> {
478 self.diagnostic().has_errors()
480 pub fn has_errors_or_delayed_span_bugs(&self) -> bool {
481 self.diagnostic().has_errors_or_delayed_span_bugs()
483 pub fn abort_if_errors(&self) {
484 self.diagnostic().abort_if_errors();
486 pub fn compile_status(&self) -> Result<(), ErrorGuaranteed> {
487 if let Some(reported) = self.diagnostic().has_errors_or_lint_errors() {
488 let _ = self.diagnostic().emit_stashed_diagnostics();
494 // FIXME(matthewjasper) Remove this method, it should never be needed.
495 pub fn track_errors<F, T>(&self, f: F) -> Result<T, ErrorGuaranteed>
499 let old_count = self.err_count();
501 if self.err_count() == old_count {
504 Err(ErrorGuaranteed::unchecked_claim_error_was_emitted())
507 pub fn span_warn<S: Into<MultiSpan>>(&self, sp: S, msg: impl Into<DiagnosticMessage>) {
508 self.diagnostic().span_warn(sp, msg)
510 pub fn span_warn_with_code<S: Into<MultiSpan>>(
513 msg: impl Into<DiagnosticMessage>,
516 self.diagnostic().span_warn_with_code(sp, msg, code)
518 pub fn warn(&self, msg: impl Into<DiagnosticMessage>) {
519 self.diagnostic().warn(msg)
521 /// Delay a span_bug() call until abort_if_errors()
523 pub fn delay_span_bug<S: Into<MultiSpan>>(
526 msg: impl Into<DiagnosticMessage>,
527 ) -> ErrorGuaranteed {
528 self.diagnostic().delay_span_bug(sp, msg)
531 /// Used for code paths of expensive computations that should only take place when
532 /// warnings or errors are emitted. If no messages are emitted ("good path"), then
533 /// it's likely a bug.
534 pub fn delay_good_path_bug(&self, msg: impl Into<DiagnosticMessage>) {
535 if self.opts.debugging_opts.print_type_sizes
536 || self.opts.debugging_opts.query_dep_graph
537 || self.opts.debugging_opts.dump_mir.is_some()
538 || self.opts.debugging_opts.unpretty.is_some()
539 || self.opts.output_types.contains_key(&OutputType::Mir)
540 || std::env::var_os("RUSTC_LOG").is_some()
545 self.diagnostic().delay_good_path_bug(msg)
548 pub fn note_without_error(&self, msg: impl Into<DiagnosticMessage>) {
549 self.diagnostic().note_without_error(msg)
551 pub fn span_note_without_error<S: Into<MultiSpan>>(
554 msg: impl Into<DiagnosticMessage>,
556 self.diagnostic().span_note_without_error(sp, msg)
558 pub fn struct_note_without_error(
560 msg: impl Into<DiagnosticMessage>,
561 ) -> DiagnosticBuilder<'_, ()> {
562 self.diagnostic().struct_note_without_error(msg)
566 pub fn diagnostic(&self) -> &rustc_errors::Handler {
567 &self.parse_sess.span_diagnostic
571 pub fn source_map(&self) -> &SourceMap {
572 self.parse_sess.source_map()
574 pub fn verbose(&self) -> bool {
575 self.opts.debugging_opts.verbose
577 pub fn time_passes(&self) -> bool {
578 self.opts.debugging_opts.time_passes || self.opts.debugging_opts.time
580 pub fn instrument_mcount(&self) -> bool {
581 self.opts.debugging_opts.instrument_mcount
583 pub fn time_llvm_passes(&self) -> bool {
584 self.opts.debugging_opts.time_llvm_passes
586 pub fn meta_stats(&self) -> bool {
587 self.opts.debugging_opts.meta_stats
589 pub fn asm_comments(&self) -> bool {
590 self.opts.debugging_opts.asm_comments
592 pub fn verify_llvm_ir(&self) -> bool {
593 self.opts.debugging_opts.verify_llvm_ir || option_env!("RUSTC_VERIFY_LLVM_IR").is_some()
595 pub fn print_llvm_passes(&self) -> bool {
596 self.opts.debugging_opts.print_llvm_passes
598 pub fn binary_dep_depinfo(&self) -> bool {
599 self.opts.debugging_opts.binary_dep_depinfo
601 pub fn mir_opt_level(&self) -> usize {
602 self.opts.mir_opt_level()
605 /// Gets the features enabled for the current compilation session.
606 /// DO NOT USE THIS METHOD if there is a TyCtxt available, as it circumvents
607 /// dependency tracking. Use tcx.features() instead.
609 pub fn features_untracked(&self) -> &rustc_feature::Features {
610 self.features.get().unwrap()
613 pub fn init_features(&self, features: rustc_feature::Features) {
614 match self.features.set(features) {
616 Err(_) => panic!("`features` was initialized twice"),
620 /// Calculates the flavor of LTO to use for this compilation.
621 pub fn lto(&self) -> config::Lto {
622 // If our target has codegen requirements ignore the command line
623 if self.target.requires_lto {
624 return config::Lto::Fat;
627 // If the user specified something, return that. If they only said `-C
628 // lto` and we've for whatever reason forced off ThinLTO via the CLI,
629 // then ensure we can't use a ThinLTO.
630 match self.opts.cg.lto {
631 config::LtoCli::Unspecified => {
632 // The compiler was invoked without the `-Clto` flag. Fall
633 // through to the default handling
635 config::LtoCli::No => {
636 // The user explicitly opted out of any kind of LTO
637 return config::Lto::No;
639 config::LtoCli::Yes | config::LtoCli::Fat | config::LtoCli::NoParam => {
640 // All of these mean fat LTO
641 return config::Lto::Fat;
643 config::LtoCli::Thin => {
644 return if self.opts.cli_forced_thinlto_off {
652 // Ok at this point the target doesn't require anything and the user
653 // hasn't asked for anything. Our next decision is whether or not
654 // we enable "auto" ThinLTO where we use multiple codegen units and
655 // then do ThinLTO over those codegen units. The logic below will
656 // either return `No` or `ThinLocal`.
658 // If processing command line options determined that we're incompatible
659 // with ThinLTO (e.g., `-C lto --emit llvm-ir`) then return that option.
660 if self.opts.cli_forced_thinlto_off {
661 return config::Lto::No;
664 // If `-Z thinlto` specified process that, but note that this is mostly
665 // a deprecated option now that `-C lto=thin` exists.
666 if let Some(enabled) = self.opts.debugging_opts.thinlto {
668 return config::Lto::ThinLocal;
670 return config::Lto::No;
674 // If there's only one codegen unit and LTO isn't enabled then there's
675 // no need for ThinLTO so just return false.
676 if self.codegen_units() == 1 {
677 return config::Lto::No;
680 // Now we're in "defaults" territory. By default we enable ThinLTO for
681 // optimized compiles (anything greater than O0).
682 match self.opts.optimize {
683 config::OptLevel::No => config::Lto::No,
684 _ => config::Lto::ThinLocal,
688 /// Returns the panic strategy for this compile session. If the user explicitly selected one
689 /// using '-C panic', use that, otherwise use the panic strategy defined by the target.
690 pub fn panic_strategy(&self) -> PanicStrategy {
691 self.opts.cg.panic.unwrap_or(self.target.panic_strategy)
693 pub fn fewer_names(&self) -> bool {
694 if let Some(fewer_names) = self.opts.debugging_opts.fewer_names {
697 let more_names = self.opts.output_types.contains_key(&OutputType::LlvmAssembly)
698 || self.opts.output_types.contains_key(&OutputType::Bitcode)
699 // AddressSanitizer and MemorySanitizer use alloca name when reporting an issue.
700 || self.opts.debugging_opts.sanitizer.intersects(SanitizerSet::ADDRESS | SanitizerSet::MEMORY);
705 pub fn unstable_options(&self) -> bool {
706 self.opts.debugging_opts.unstable_options
708 pub fn is_nightly_build(&self) -> bool {
709 self.opts.unstable_features.is_nightly_build()
711 pub fn is_sanitizer_cfi_enabled(&self) -> bool {
712 self.opts.debugging_opts.sanitizer.contains(SanitizerSet::CFI)
714 pub fn overflow_checks(&self) -> bool {
715 self.opts.cg.overflow_checks.unwrap_or(self.opts.debug_assertions)
718 /// Check whether this compile session and crate type use static crt.
719 pub fn crt_static(&self, crate_type: Option<CrateType>) -> bool {
720 if !self.target.crt_static_respected {
721 // If the target does not opt in to crt-static support, use its default.
722 return self.target.crt_static_default;
725 let requested_features = self.opts.cg.target_feature.split(',');
726 let found_negative = requested_features.clone().any(|r| r == "-crt-static");
727 let found_positive = requested_features.clone().any(|r| r == "+crt-static");
729 if found_positive || found_negative {
731 } else if crate_type == Some(CrateType::ProcMacro)
732 || crate_type == None && self.opts.crate_types.contains(&CrateType::ProcMacro)
734 // FIXME: When crate_type is not available,
735 // we use compiler options to determine the crate_type.
736 // We can't check `#![crate_type = "proc-macro"]` here.
739 self.target.crt_static_default
743 pub fn relocation_model(&self) -> RelocModel {
744 self.opts.cg.relocation_model.unwrap_or(self.target.relocation_model)
747 pub fn code_model(&self) -> Option<CodeModel> {
748 self.opts.cg.code_model.or(self.target.code_model)
751 pub fn tls_model(&self) -> TlsModel {
752 self.opts.debugging_opts.tls_model.unwrap_or(self.target.tls_model)
755 pub fn is_wasi_reactor(&self) -> bool {
756 self.target.options.os == "wasi"
758 self.opts.debugging_opts.wasi_exec_model,
759 Some(config::WasiExecModel::Reactor)
763 pub fn split_debuginfo(&self) -> SplitDebuginfo {
764 self.opts.cg.split_debuginfo.unwrap_or(self.target.split_debuginfo)
767 pub fn stack_protector(&self) -> StackProtector {
768 if self.target.options.supports_stack_protector {
769 self.opts.debugging_opts.stack_protector
775 pub fn target_can_use_split_dwarf(&self) -> bool {
776 !self.target.is_like_windows && !self.target.is_like_osx
779 pub fn must_emit_unwind_tables(&self) -> bool {
780 // This is used to control the emission of the `uwtable` attribute on
783 // Unwind tables are needed when compiling with `-C panic=unwind`, but
784 // LLVM won't omit unwind tables unless the function is also marked as
785 // `nounwind`, so users are allowed to disable `uwtable` emission.
786 // Historically rustc always emits `uwtable` attributes by default, so
787 // even they can be disabled, they're still emitted by default.
789 // On some targets (including windows), however, exceptions include
790 // other events such as illegal instructions, segfaults, etc. This means
791 // that on Windows we end up still needing unwind tables even if the `-C
792 // panic=abort` flag is passed.
794 // You can also find more info on why Windows needs unwind tables in:
795 // https://bugzilla.mozilla.org/show_bug.cgi?id=1302078
797 // If a target requires unwind tables, then they must be emitted.
798 // Otherwise, we can defer to the `-C force-unwind-tables=<yes/no>`
799 // value, if it is provided, or disable them, if not.
800 self.target.requires_uwtable
801 || self.opts.cg.force_unwind_tables.unwrap_or(
802 self.panic_strategy() == PanicStrategy::Unwind || self.target.default_uwtable,
806 pub fn generate_proc_macro_decls_symbol(&self, stable_crate_id: StableCrateId) -> String {
807 format!("__rustc_proc_macro_decls_{:08x}__", stable_crate_id.to_u64())
810 pub fn target_filesearch(&self, kind: PathKind) -> filesearch::FileSearch<'_> {
811 filesearch::FileSearch::new(
813 self.opts.target_triple.triple(),
814 &self.opts.search_paths,
815 &self.target_tlib_path,
819 pub fn host_filesearch(&self, kind: PathKind) -> filesearch::FileSearch<'_> {
820 filesearch::FileSearch::new(
822 config::host_triple(),
823 &self.opts.search_paths,
824 &self.host_tlib_path,
829 /// Returns a list of directories where target-specific tool binaries are located.
830 pub fn get_tools_search_paths(&self, self_contained: bool) -> Vec<PathBuf> {
831 let rustlib_path = rustc_target::target_rustlib_path(&self.sysroot, &config::host_triple());
832 let p = PathBuf::from_iter([
833 Path::new(&self.sysroot),
834 Path::new(&rustlib_path),
837 if self_contained { vec![p.clone(), p.join("self-contained")] } else { vec![p] }
840 pub fn init_incr_comp_session(
842 session_dir: PathBuf,
843 lock_file: flock::Lock,
844 load_dep_graph: bool,
846 let mut incr_comp_session = self.incr_comp_session.borrow_mut();
848 if let IncrCompSession::NotInitialized = *incr_comp_session {
850 panic!("Trying to initialize IncrCompSession `{:?}`", *incr_comp_session)
854 IncrCompSession::Active { session_directory: session_dir, lock_file, load_dep_graph };
857 pub fn finalize_incr_comp_session(&self, new_directory_path: PathBuf) {
858 let mut incr_comp_session = self.incr_comp_session.borrow_mut();
860 if let IncrCompSession::Active { .. } = *incr_comp_session {
862 panic!("trying to finalize `IncrCompSession` `{:?}`", *incr_comp_session);
865 // Note: this will also drop the lock file, thus unlocking the directory.
866 *incr_comp_session = IncrCompSession::Finalized { session_directory: new_directory_path };
869 pub fn mark_incr_comp_session_as_invalid(&self) {
870 let mut incr_comp_session = self.incr_comp_session.borrow_mut();
872 let session_directory = match *incr_comp_session {
873 IncrCompSession::Active { ref session_directory, .. } => session_directory.clone(),
874 IncrCompSession::InvalidBecauseOfErrors { .. } => return,
875 _ => panic!("trying to invalidate `IncrCompSession` `{:?}`", *incr_comp_session),
878 // Note: this will also drop the lock file, thus unlocking the directory.
879 *incr_comp_session = IncrCompSession::InvalidBecauseOfErrors { session_directory };
882 pub fn incr_comp_session_dir(&self) -> cell::Ref<'_, PathBuf> {
883 let incr_comp_session = self.incr_comp_session.borrow();
884 cell::Ref::map(incr_comp_session, |incr_comp_session| match *incr_comp_session {
885 IncrCompSession::NotInitialized => panic!(
886 "trying to get session directory from `IncrCompSession`: {:?}",
889 IncrCompSession::Active { ref session_directory, .. }
890 | IncrCompSession::Finalized { ref session_directory }
891 | IncrCompSession::InvalidBecauseOfErrors { ref session_directory } => {
897 pub fn incr_comp_session_dir_opt(&self) -> Option<cell::Ref<'_, PathBuf>> {
898 self.opts.incremental.as_ref().map(|_| self.incr_comp_session_dir())
901 pub fn print_perf_stats(&self) {
903 "Total time spent computing symbol hashes: {}",
904 duration_to_secs_str(*self.perf_stats.symbol_hash_time.lock())
907 "Total queries canonicalized: {}",
908 self.perf_stats.queries_canonicalized.load(Ordering::Relaxed)
911 "normalize_generic_arg_after_erasing_regions: {}",
912 self.perf_stats.normalize_generic_arg_after_erasing_regions.load(Ordering::Relaxed)
915 "normalize_projection_ty: {}",
916 self.perf_stats.normalize_projection_ty.load(Ordering::Relaxed)
920 /// We want to know if we're allowed to do an optimization for crate foo from -z fuel=foo=n.
921 /// This expends fuel if applicable, and records fuel if applicable.
922 pub fn consider_optimizing<T: Fn() -> String>(&self, crate_name: &str, msg: T) -> bool {
924 if let Some((ref c, _)) = self.opts.debugging_opts.fuel {
926 assert_eq!(self.threads(), 1);
927 let mut fuel = self.optimization_fuel.lock();
928 ret = fuel.remaining != 0;
929 if fuel.remaining == 0 && !fuel.out_of_fuel {
930 if self.diagnostic().can_emit_warnings() {
931 // We only call `msg` in case we can actually emit warnings.
932 // Otherwise, this could cause a `delay_good_path_bug` to
933 // trigger (issue #79546).
934 self.warn(&format!("optimization-fuel-exhausted: {}", msg()));
936 fuel.out_of_fuel = true;
937 } else if fuel.remaining > 0 {
942 if let Some(ref c) = self.opts.debugging_opts.print_fuel {
944 assert_eq!(self.threads(), 1);
945 self.print_fuel.fetch_add(1, SeqCst);
951 /// Returns the number of query threads that should be used for this
953 pub fn threads(&self) -> usize {
954 self.opts.debugging_opts.threads
957 /// Returns the number of codegen units that should be used for this
959 pub fn codegen_units(&self) -> usize {
960 if let Some(n) = self.opts.cli_forced_codegen_units {
963 if let Some(n) = self.target.default_codegen_units {
967 // If incremental compilation is turned on, we default to a high number
968 // codegen units in order to reduce the "collateral damage" small
970 if self.opts.incremental.is_some() {
974 // Why is 16 codegen units the default all the time?
976 // The main reason for enabling multiple codegen units by default is to
977 // leverage the ability for the codegen backend to do codegen and
978 // optimization in parallel. This allows us, especially for large crates, to
979 // make good use of all available resources on the machine once we've
980 // hit that stage of compilation. Large crates especially then often
981 // take a long time in codegen/optimization and this helps us amortize that
984 // Note that a high number here doesn't mean that we'll be spawning a
985 // large number of threads in parallel. The backend of rustc contains
986 // global rate limiting through the `jobserver` crate so we'll never
987 // overload the system with too much work, but rather we'll only be
988 // optimizing when we're otherwise cooperating with other instances of
991 // Rather a high number here means that we should be able to keep a lot
992 // of idle cpus busy. By ensuring that no codegen unit takes *too* long
993 // to build we'll be guaranteed that all cpus will finish pretty closely
994 // to one another and we should make relatively optimal use of system
997 // Note that the main cost of codegen units is that it prevents LLVM
998 // from inlining across codegen units. Users in general don't have a lot
999 // of control over how codegen units are split up so it's our job in the
1000 // compiler to ensure that undue performance isn't lost when using
1001 // codegen units (aka we can't require everyone to slap `#[inline]` on
1004 // If we're compiling at `-O0` then the number doesn't really matter too
1005 // much because performance doesn't matter and inlining is ok to lose.
1006 // In debug mode we just want to try to guarantee that no cpu is stuck
1007 // doing work that could otherwise be farmed to others.
1009 // In release mode, however (O1 and above) performance does indeed
1010 // matter! To recover the loss in performance due to inlining we'll be
1011 // enabling ThinLTO by default (the function for which is just below).
1012 // This will ensure that we recover any inlining wins we otherwise lost
1013 // through codegen unit partitioning.
1017 // Ok that's a lot of words but the basic tl;dr; is that we want a high
1018 // number here -- but not too high. Additionally we're "safe" to have it
1019 // always at the same number at all optimization levels.
1021 // As a result 16 was chosen here! Mostly because it was a power of 2
1022 // and most benchmarks agreed it was roughly a local optimum. Not very
1027 pub fn teach(&self, code: &DiagnosticId) -> bool {
1028 self.opts.debugging_opts.teach && self.diagnostic().must_teach(code)
1031 pub fn rust_2015(&self) -> bool {
1032 self.opts.edition == Edition::Edition2015
1035 /// Are we allowed to use features from the Rust 2018 edition?
1036 pub fn rust_2018(&self) -> bool {
1037 self.opts.edition >= Edition::Edition2018
1040 /// Are we allowed to use features from the Rust 2021 edition?
1041 pub fn rust_2021(&self) -> bool {
1042 self.opts.edition >= Edition::Edition2021
1045 /// Are we allowed to use features from the Rust 2024 edition?
1046 pub fn rust_2024(&self) -> bool {
1047 self.opts.edition >= Edition::Edition2024
1050 pub fn edition(&self) -> Edition {
1054 /// Returns `true` if we cannot skip the PLT for shared library calls.
1055 pub fn needs_plt(&self) -> bool {
1056 // Check if the current target usually needs PLT to be enabled.
1057 // The user can use the command line flag to override it.
1058 let needs_plt = self.target.needs_plt;
1060 let dbg_opts = &self.opts.debugging_opts;
1062 let relro_level = dbg_opts.relro_level.unwrap_or(self.target.relro_level);
1064 // Only enable this optimization by default if full relro is also enabled.
1065 // In this case, lazy binding was already unavailable, so nothing is lost.
1066 // This also ensures `-Wl,-z,now` is supported by the linker.
1067 let full_relro = RelroLevel::Full == relro_level;
1069 // If user didn't explicitly forced us to use / skip the PLT,
1070 // then try to skip it where possible.
1071 dbg_opts.plt.unwrap_or(needs_plt || !full_relro)
1074 /// Checks if LLVM lifetime markers should be emitted.
1075 pub fn emit_lifetime_markers(&self) -> bool {
1076 self.opts.optimize != config::OptLevel::No
1077 // AddressSanitizer uses lifetimes to detect use after scope bugs.
1078 // MemorySanitizer uses lifetimes to detect use of uninitialized stack variables.
1079 // HWAddressSanitizer will use lifetimes to detect use after scope bugs in the future.
1080 || self.opts.debugging_opts.sanitizer.intersects(SanitizerSet::ADDRESS | SanitizerSet::MEMORY | SanitizerSet::HWADDRESS)
1083 pub fn link_dead_code(&self) -> bool {
1084 self.opts.cg.link_dead_code.unwrap_or(false)
1087 pub fn instrument_coverage(&self) -> bool {
1088 self.opts.instrument_coverage()
1091 pub fn instrument_coverage_except_unused_generics(&self) -> bool {
1092 self.opts.instrument_coverage_except_unused_generics()
1095 pub fn instrument_coverage_except_unused_functions(&self) -> bool {
1096 self.opts.instrument_coverage_except_unused_functions()
1099 pub fn is_proc_macro_attr(&self, attr: &Attribute) -> bool {
1100 [sym::proc_macro, sym::proc_macro_attribute, sym::proc_macro_derive]
1102 .any(|kind| attr.has_name(*kind))
1105 pub fn contains_name(&self, attrs: &[Attribute], name: Symbol) -> bool {
1106 attrs.iter().any(|item| item.has_name(name))
1109 pub fn find_by_name<'a>(
1111 attrs: &'a [Attribute],
1113 ) -> Option<&'a Attribute> {
1114 attrs.iter().find(|attr| attr.has_name(name))
1117 pub fn filter_by_name<'a>(
1119 attrs: &'a [Attribute],
1121 ) -> impl Iterator<Item = &'a Attribute> {
1122 attrs.iter().filter(move |attr| attr.has_name(name))
1125 pub fn first_attr_value_str_by_name(
1127 attrs: &[Attribute],
1129 ) -> Option<Symbol> {
1130 attrs.iter().find(|at| at.has_name(name)).and_then(|at| at.value_str())
1135 sopts: &config::Options,
1136 registry: rustc_errors::registry::Registry,
1137 source_map: Lrc<SourceMap>,
1138 bundle: Option<Lrc<FluentBundle>>,
1139 fallback_bundle: LazyFallbackBundle,
1140 emitter_dest: Option<Box<dyn Write + Send>>,
1141 ) -> Box<dyn Emitter + sync::Send> {
1142 let macro_backtrace = sopts.debugging_opts.macro_backtrace;
1143 match (sopts.error_format, emitter_dest) {
1144 (config::ErrorOutputType::HumanReadable(kind), dst) => {
1145 let (short, color_config) = kind.unzip();
1147 if let HumanReadableErrorType::AnnotateSnippet(_) = kind {
1148 let emitter = AnnotateSnippetEmitterWriter::new(
1155 Box::new(emitter.ui_testing(sopts.debugging_opts.ui_testing))
1157 let emitter = match dst {
1158 None => EmitterWriter::stderr(
1164 sopts.debugging_opts.teach,
1165 sopts.debugging_opts.terminal_width,
1168 Some(dst) => EmitterWriter::new(
1174 false, // no teach messages when writing to a buffer
1175 false, // no colors when writing to a buffer
1176 None, // no terminal width
1180 Box::new(emitter.ui_testing(sopts.debugging_opts.ui_testing))
1183 (config::ErrorOutputType::Json { pretty, json_rendered }, None) => Box::new(
1184 JsonEmitter::stderr(
1191 sopts.debugging_opts.terminal_width,
1194 .ui_testing(sopts.debugging_opts.ui_testing),
1196 (config::ErrorOutputType::Json { pretty, json_rendered }, Some(dst)) => Box::new(
1205 sopts.debugging_opts.terminal_width,
1208 .ui_testing(sopts.debugging_opts.ui_testing),
1213 pub enum DiagnosticOutput {
1215 Raw(Box<dyn Write + Send>),
1218 pub fn build_session(
1219 sopts: config::Options,
1220 local_crate_source_file: Option<PathBuf>,
1221 bundle: Option<Lrc<rustc_errors::FluentBundle>>,
1222 registry: rustc_errors::registry::Registry,
1223 diagnostics_output: DiagnosticOutput,
1224 driver_lint_caps: FxHashMap<lint::LintId, lint::Level>,
1225 file_loader: Option<Box<dyn FileLoader + Send + Sync + 'static>>,
1226 target_override: Option<Target>,
1228 // FIXME: This is not general enough to make the warning lint completely override
1229 // normal diagnostic warnings, since the warning lint can also be denied and changed
1230 // later via the source code.
1231 let warnings_allow = sopts
1234 .filter(|&&(ref key, _)| *key == "warnings")
1235 .map(|&(_, ref level)| *level == lint::Allow)
1238 let cap_lints_allow = sopts.lint_cap.map_or(false, |cap| cap == lint::Allow);
1239 let can_emit_warnings = !(warnings_allow || cap_lints_allow);
1241 let write_dest = match diagnostics_output {
1242 DiagnosticOutput::Default => None,
1243 DiagnosticOutput::Raw(write) => Some(write),
1246 let sysroot = match &sopts.maybe_sysroot {
1247 Some(sysroot) => sysroot.clone(),
1248 None => filesearch::get_or_default_sysroot(),
1251 let target_cfg = config::build_target_config(&sopts, target_override, &sysroot);
1252 let host_triple = TargetTriple::from_triple(config::host_triple());
1253 let (host, target_warnings) = Target::search(&host_triple, &sysroot).unwrap_or_else(|e| {
1254 early_error(sopts.error_format, &format!("Error loading host specification: {e}"))
1256 for warning in target_warnings.warning_messages() {
1257 early_warn(sopts.error_format, &warning)
1260 let loader = file_loader.unwrap_or_else(|| Box::new(RealFileLoader));
1261 let hash_kind = sopts.debugging_opts.src_hash_algorithm.unwrap_or_else(|| {
1262 if target_cfg.is_like_msvc {
1263 SourceFileHashAlgorithm::Sha1
1265 SourceFileHashAlgorithm::Md5
1268 let source_map = Lrc::new(SourceMap::with_file_loader_and_hash_kind(
1270 sopts.file_path_mapping(),
1274 let fallback_bundle = fallback_fluent_bundle(
1275 rustc_errors::DEFAULT_LOCALE_RESOURCES,
1276 sopts.debugging_opts.translate_directionality_markers,
1279 default_emitter(&sopts, registry, source_map.clone(), bundle, fallback_bundle, write_dest);
1281 let span_diagnostic = rustc_errors::Handler::with_emitter_and_flags(
1283 sopts.debugging_opts.diagnostic_handler_flags(can_emit_warnings),
1286 let self_profiler = if let SwitchWithOptPath::Enabled(ref d) = sopts.debugging_opts.self_profile
1289 if let Some(ref directory) = d { directory } else { std::path::Path::new(".") };
1291 let profiler = SelfProfiler::new(
1293 sopts.crate_name.as_deref(),
1294 sopts.debugging_opts.self_profile_events.as_ref().map(|xs| &xs[..]),
1295 &sopts.debugging_opts.self_profile_counter,
1298 Ok(profiler) => Some(Arc::new(profiler)),
1300 early_warn(sopts.error_format, &format!("failed to create profiler: {e}"));
1308 let mut parse_sess = ParseSess::with_span_handler(span_diagnostic, source_map);
1309 parse_sess.assume_incomplete_release = sopts.debugging_opts.assume_incomplete_release;
1311 let host_triple = config::host_triple();
1312 let target_triple = sopts.target_triple.triple();
1313 let host_tlib_path = Lrc::new(SearchPath::from_sysroot_and_triple(&sysroot, host_triple));
1314 let target_tlib_path = if host_triple == target_triple {
1315 // Use the same `SearchPath` if host and target triple are identical to avoid unnecessary
1316 // rescanning of the target lib path and an unnecessary allocation.
1317 host_tlib_path.clone()
1319 Lrc::new(SearchPath::from_sysroot_and_triple(&sysroot, target_triple))
1322 let file_path_mapping = sopts.file_path_mapping();
1324 let local_crate_source_file =
1325 local_crate_source_file.map(|path| file_path_mapping.map_prefix(path).0);
1327 let optimization_fuel = Lock::new(OptimizationFuel {
1328 remaining: sopts.debugging_opts.fuel.as_ref().map_or(0, |i| i.1),
1331 let print_fuel = AtomicU64::new(0);
1333 let cgu_reuse_tracker = if sopts.debugging_opts.query_dep_graph {
1334 CguReuseTracker::new()
1336 CguReuseTracker::new_disabled()
1339 let prof = SelfProfilerRef::new(
1341 sopts.debugging_opts.time_passes || sopts.debugging_opts.time,
1342 sopts.debugging_opts.time_passes,
1345 let ctfe_backtrace = Lock::new(match env::var("RUSTC_CTFE_BACKTRACE") {
1346 Ok(ref val) if val == "immediate" => CtfeBacktrace::Immediate,
1347 Ok(ref val) if val != "0" => CtfeBacktrace::Capture,
1348 _ => CtfeBacktrace::Disabled,
1352 if target_cfg.allow_asm { InlineAsmArch::from_str(&target_cfg.arch).ok() } else { None };
1354 let sess = Session {
1362 local_crate_source_file,
1363 crate_types: OnceCell::new(),
1364 stable_crate_id: OnceCell::new(),
1365 features: OnceCell::new(),
1366 incr_comp_session: OneThread::new(RefCell::new(IncrCompSession::NotInitialized)),
1369 perf_stats: PerfStats {
1370 symbol_hash_time: Lock::new(Duration::from_secs(0)),
1371 queries_canonicalized: AtomicUsize::new(0),
1372 normalize_generic_arg_after_erasing_regions: AtomicUsize::new(0),
1373 normalize_projection_ty: AtomicUsize::new(0),
1375 code_stats: Default::default(),
1378 jobserver: jobserver::client(),
1381 miri_unleashed_features: Lock::new(Default::default()),
1383 target_features: FxHashSet::default(),
1386 validate_commandline_args_with_session_available(&sess);
1391 // If it is useful to have a Session available already for validating a
1392 // commandline argument, you can do so here.
1393 fn validate_commandline_args_with_session_available(sess: &Session) {
1394 // Since we don't know if code in an rlib will be linked to statically or
1395 // dynamically downstream, rustc generates `__imp_` symbols that help linkers
1396 // on Windows deal with this lack of knowledge (#27438). Unfortunately,
1397 // these manually generated symbols confuse LLD when it tries to merge
1398 // bitcode during ThinLTO. Therefore we disallow dynamic linking on Windows
1399 // when compiling for LLD ThinLTO. This way we can validly just not generate
1400 // the `dllimport` attributes and `__imp_` symbols in that case.
1401 if sess.opts.cg.linker_plugin_lto.enabled()
1402 && sess.opts.cg.prefer_dynamic
1403 && sess.target.is_like_windows
1406 "Linker plugin based LTO is not supported together with \
1407 `-C prefer-dynamic` when targeting Windows-like targets",
1411 // Make sure that any given profiling data actually exists so LLVM can't
1412 // decide to silently skip PGO.
1413 if let Some(ref path) = sess.opts.cg.profile_use {
1416 "File `{}` passed to `-C profile-use` does not exist.",
1422 // Do the same for sample profile data.
1423 if let Some(ref path) = sess.opts.debugging_opts.profile_sample_use {
1426 "File `{}` passed to `-C profile-sample-use` does not exist.",
1432 // Unwind tables cannot be disabled if the target requires them.
1433 if let Some(include_uwtables) = sess.opts.cg.force_unwind_tables {
1434 if sess.target.requires_uwtable && !include_uwtables {
1436 "target requires unwind tables, they cannot be disabled with \
1437 `-C force-unwind-tables=no`.",
1442 // Sanitizers can only be used on platforms that we know have working sanitizer codegen.
1443 let supported_sanitizers = sess.target.options.supported_sanitizers;
1444 let unsupported_sanitizers = sess.opts.debugging_opts.sanitizer - supported_sanitizers;
1445 match unsupported_sanitizers.into_iter().count() {
1449 "{} sanitizer is not supported for this target",
1450 unsupported_sanitizers
1455 "{} sanitizers are not supported for this target",
1456 unsupported_sanitizers
1460 // Cannot mix and match sanitizers.
1461 let mut sanitizer_iter = sess.opts.debugging_opts.sanitizer.into_iter();
1462 if let (Some(first), Some(second)) = (sanitizer_iter.next(), sanitizer_iter.next()) {
1463 sess.err(&format!("`-Zsanitizer={first}` is incompatible with `-Zsanitizer={second}`"));
1466 // Cannot enable crt-static with sanitizers on Linux
1467 if sess.crt_static(None) && !sess.opts.debugging_opts.sanitizer.is_empty() {
1469 "sanitizer is incompatible with statically linked libc, \
1470 disable it using `-C target-feature=-crt-static`",
1474 // LLVM CFI and VFE both require LTO.
1475 if sess.lto() != config::Lto::Fat {
1476 if sess.is_sanitizer_cfi_enabled() {
1477 sess.err("`-Zsanitizer=cfi` requires `-Clto`");
1479 if sess.opts.debugging_opts.virtual_function_elimination {
1480 sess.err("`-Zvirtual-function-elimination` requires `-Clto`");
1484 if sess.opts.debugging_opts.stack_protector != StackProtector::None {
1485 if !sess.target.options.supports_stack_protector {
1487 "`-Z stack-protector={}` is not supported for target {} and will be ignored",
1488 sess.opts.debugging_opts.stack_protector, sess.opts.target_triple
1494 /// Holds data on the current incremental compilation session, if there is one.
1496 pub enum IncrCompSession {
1497 /// This is the state the session will be in until the incr. comp. dir is
1500 /// This is the state during which the session directory is private and can
1502 Active { session_directory: PathBuf, lock_file: flock::Lock, load_dep_graph: bool },
1503 /// This is the state after the session directory has been finalized. In this
1504 /// state, the contents of the directory must not be modified any more.
1505 Finalized { session_directory: PathBuf },
1506 /// This is an error state that is reached when some compilation error has
1507 /// occurred. It indicates that the contents of the session directory must
1508 /// not be used, since they might be invalid.
1509 InvalidBecauseOfErrors { session_directory: PathBuf },
1512 fn early_error_handler(output: config::ErrorOutputType) -> rustc_errors::Handler {
1513 let fallback_bundle = fallback_fluent_bundle(rustc_errors::DEFAULT_LOCALE_RESOURCES, false);
1514 let emitter: Box<dyn Emitter + sync::Send> = match output {
1515 config::ErrorOutputType::HumanReadable(kind) => {
1516 let (short, color_config) = kind.unzip();
1517 Box::new(EmitterWriter::stderr(
1528 config::ErrorOutputType::Json { pretty, json_rendered } => {
1529 Box::new(JsonEmitter::basic(pretty, json_rendered, None, fallback_bundle, None, false))
1532 rustc_errors::Handler::with_emitter(true, None, emitter)
1535 pub fn early_error_no_abort(output: config::ErrorOutputType, msg: &str) -> ErrorGuaranteed {
1536 early_error_handler(output).struct_err(msg).emit()
1539 pub fn early_error(output: config::ErrorOutputType, msg: &str) -> ! {
1540 early_error_handler(output).struct_fatal(msg).emit()
1543 pub fn early_warn(output: config::ErrorOutputType, msg: &str) {
1544 early_error_handler(output).struct_warn(msg).emit()