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};
6 use crate::lint::{self, LintId};
7 use crate::parse::ParseSess;
8 use crate::search_paths::{PathKind, SearchPath};
10 pub use rustc_ast::attr::MarkedAttrs;
11 pub use rustc_ast::Attribute;
12 use rustc_data_structures::flock;
13 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
14 use rustc_data_structures::jobserver::{self, Client};
15 use rustc_data_structures::profiling::{duration_to_secs_str, SelfProfiler, SelfProfilerRef};
16 use rustc_data_structures::sync::{
17 self, AtomicU64, AtomicUsize, Lock, Lrc, OnceCell, OneThread, Ordering, Ordering::SeqCst,
19 use rustc_errors::annotate_snippet_emitter_writer::AnnotateSnippetEmitterWriter;
20 use rustc_errors::emitter::{Emitter, EmitterWriter, HumanReadableErrorType};
21 use rustc_errors::json::JsonEmitter;
22 use rustc_errors::registry::Registry;
23 use rustc_errors::{DiagnosticBuilder, DiagnosticId, ErrorReported};
24 use rustc_macros::HashStable_Generic;
25 pub use rustc_span::def_id::StableCrateId;
26 use rustc_span::source_map::{FileLoader, MultiSpan, RealFileLoader, SourceMap, Span};
27 use rustc_span::{edition::Edition, RealFileName};
28 use rustc_span::{sym, SourceFileHashAlgorithm, Symbol};
29 use rustc_target::asm::InlineAsmArch;
30 use rustc_target::spec::{CodeModel, PanicStrategy, RelocModel, RelroLevel};
31 use rustc_target::spec::{SanitizerSet, SplitDebuginfo, Target, TargetTriple, TlsModel};
33 use std::cell::{self, RefCell};
37 use std::num::NonZeroU32;
38 use std::ops::{Div, Mul};
39 use std::path::PathBuf;
40 use std::str::FromStr;
42 use std::time::Duration;
44 pub trait SessionLintStore: sync::Send + sync::Sync {
45 fn name_to_lint(&self, lint_name: &str) -> LintId;
48 pub struct OptimizationFuel {
49 /// If `-zfuel=crate=n` is specified, initially set to `n`, otherwise `0`.
51 /// We're rejecting all further optimizations.
55 /// The behavior of the CTFE engine when an error occurs with regards to backtraces.
56 #[derive(Clone, Copy)]
57 pub enum CtfeBacktrace {
58 /// Do nothing special, return the error as usual without a backtrace.
60 /// Capture a backtrace at the point the error is created and return it in the error
61 /// (to be printed later if/when the error ever actually gets shown to the user).
63 /// Capture a backtrace at the point the error is created and immediately print it out.
67 /// New-type wrapper around `usize` for representing limits. Ensures that comparisons against
68 /// limits are consistent throughout the compiler.
69 #[derive(Clone, Copy, Debug, HashStable_Generic)]
70 pub struct Limit(pub usize);
73 /// Create a new limit from a `usize`.
74 pub fn new(value: usize) -> Self {
78 /// Check that `value` is within the limit. Ensures that the same comparisons are used
79 /// throughout the compiler, as mismatches can cause ICEs, see #72540.
81 pub fn value_within_limit(&self, value: usize) -> bool {
86 impl From<usize> for Limit {
87 fn from(value: usize) -> Self {
92 impl fmt::Display for Limit {
93 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
94 write!(f, "{}", self.0)
98 impl Div<usize> for Limit {
101 fn div(self, rhs: usize) -> Self::Output {
102 Limit::new(self.0 / rhs)
106 impl Mul<usize> for Limit {
109 fn mul(self, rhs: usize) -> Self::Output {
110 Limit::new(self.0 * rhs)
114 #[derive(Clone, Copy, Debug, HashStable_Generic)]
116 /// The maximum recursion limit for potentially infinitely recursive
117 /// operations such as auto-dereference and monomorphization.
118 pub recursion_limit: Limit,
119 /// The size at which the `large_assignments` lint starts
121 pub move_size_limit: Limit,
122 /// The maximum length of types during monomorphization.
123 pub type_length_limit: Limit,
124 /// The maximum blocks a const expression can evaluate.
125 pub const_eval_limit: Limit,
128 /// Represents the data associated with a compilation
129 /// session for a single crate.
133 pub opts: config::Options,
134 pub host_tlib_path: SearchPath,
135 /// `None` if the host and target are the same.
136 pub target_tlib_path: Option<SearchPath>,
137 pub parse_sess: ParseSess,
138 pub sysroot: PathBuf,
139 /// The name of the root source file of the crate, in the local file system.
140 /// `None` means that there is no source file.
141 pub local_crate_source_file: Option<PathBuf>,
142 /// The directory the compiler has been executed in
143 pub working_dir: RealFileName,
145 /// Set of `(DiagnosticId, Option<Span>, message)` tuples tracking
146 /// (sub)diagnostics that have been set once, but should not be set again,
147 /// in order to avoid redundantly verbose output (Issue #24690, #44953).
148 pub one_time_diagnostics: Lock<FxHashSet<(DiagnosticMessageId, Option<Span>, String)>>,
149 crate_types: OnceCell<Vec<CrateType>>,
150 /// The `stable_crate_id` is constructed out of the crate name and all the
151 /// `-C metadata` arguments passed to the compiler. Its value forms a unique
152 /// global identifier for the crate. It is used to allow multiple crates
153 /// with the same name to coexist. See the
154 /// `rustc_codegen_llvm::back::symbol_names` module for more information.
155 pub stable_crate_id: OnceCell<StableCrateId>,
157 features: OnceCell<rustc_feature::Features>,
159 lint_store: OnceCell<Lrc<dyn SessionLintStore>>,
161 incr_comp_session: OneThread<RefCell<IncrCompSession>>,
162 /// Used for incremental compilation tests. Will only be populated if
163 /// `-Zquery-dep-graph` is specified.
164 pub cgu_reuse_tracker: CguReuseTracker,
166 /// Used by `-Z self-profile`.
167 pub prof: SelfProfilerRef,
169 /// Some measurements that are being gathered during compilation.
170 pub perf_stats: PerfStats,
172 /// Data about code being compiled, gathered during compilation.
173 pub code_stats: CodeStats,
175 /// If `-zfuel=crate=n` is specified, `Some(crate)`.
176 optimization_fuel_crate: Option<String>,
178 /// Tracks fuel info if `-zfuel=crate=n` is specified.
179 optimization_fuel: Lock<OptimizationFuel>,
181 // The next two are public because the driver needs to read them.
182 /// If `-zprint-fuel=crate`, `Some(crate)`.
183 pub print_fuel_crate: Option<String>,
184 /// Always set to zero and incremented so that we can print fuel expended by a crate.
185 pub print_fuel: AtomicU64,
187 /// Loaded up early on in the initialization of this `Session` to avoid
188 /// false positives about a job server in our environment.
189 pub jobserver: Client,
191 /// Cap lint level specified by a driver specifically.
192 pub driver_lint_caps: FxHashMap<lint::LintId, lint::Level>,
194 /// `Span`s of trait methods that weren't found to avoid emitting object safety errors
195 pub trait_methods_not_found: Lock<FxHashSet<Span>>,
197 /// Mapping from ident span to path span for paths that don't exist as written, but that
198 /// exist under `std`. For example, wrote `str::from_utf8` instead of `std::str::from_utf8`.
199 pub confused_type_with_std_module: Lock<FxHashMap<Span, Span>>,
201 /// Path for libraries that will take preference over libraries shipped by Rust.
202 /// Used by windows-gnu targets to priortize system mingw-w64 libraries.
203 pub system_library_path: OneThread<RefCell<Option<Option<PathBuf>>>>,
205 /// Tracks the current behavior of the CTFE engine when an error occurs.
206 /// Options range from returning the error without a backtrace to returning an error
207 /// and immediately printing the backtrace to stderr.
208 pub ctfe_backtrace: Lock<CtfeBacktrace>,
210 /// This tracks where `-Zunleash-the-miri-inside-of-you` was used to get around a
211 /// const check, optionally with the relevant feature gate. We use this to
212 /// warn about unleashing, but with a single diagnostic instead of dozens that
213 /// drown everything else in noise.
214 miri_unleashed_features: Lock<Vec<(Span, Option<Symbol>)>>,
216 /// Architecture to use for interpreting asm!.
217 pub asm_arch: Option<InlineAsmArch>,
219 /// Set of enabled features for the current target.
220 pub target_features: FxHashSet<Symbol>,
222 known_attrs: Lock<MarkedAttrs>,
223 used_attrs: Lock<MarkedAttrs>,
225 /// `Span`s for `if` conditions that we have suggested turning into `if let`.
226 pub if_let_suggestions: Lock<FxHashSet<Span>>,
229 pub struct PerfStats {
230 /// The accumulated time spent on computing symbol hashes.
231 pub symbol_hash_time: Lock<Duration>,
232 /// Total number of values canonicalized queries constructed.
233 pub queries_canonicalized: AtomicUsize,
234 /// Number of times this query is invoked.
235 pub normalize_generic_arg_after_erasing_regions: AtomicUsize,
236 /// Number of times this query is invoked.
237 pub normalize_projection_ty: AtomicUsize,
240 /// Enum to support dispatch of one-time diagnostics (in `Session.diag_once`).
241 enum DiagnosticBuilderMethod {
244 // Add more variants as needed to support one-time diagnostics.
247 /// Trait implemented by error types. This should not be implemented manually. Instead, use
248 /// `#[derive(SessionDiagnostic)]` -- see [rustc_macros::SessionDiagnostic].
249 pub trait SessionDiagnostic<'a> {
250 /// Write out as a diagnostic out of `sess`.
252 fn into_diagnostic(self, sess: &'a Session) -> DiagnosticBuilder<'a>;
255 /// Diagnostic message ID, used by `Session.one_time_diagnostics` to avoid
256 /// emitting the same message more than once.
257 #[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
258 pub enum DiagnosticMessageId {
259 ErrorId(u16), // EXXXX error code as integer
260 LintId(lint::LintId),
261 StabilityId(Option<NonZeroU32>), // issue number
264 impl From<&'static lint::Lint> for DiagnosticMessageId {
265 fn from(lint: &'static lint::Lint) -> Self {
266 DiagnosticMessageId::LintId(lint::LintId::of(lint))
271 pub fn miri_unleashed_feature(&self, span: Span, feature_gate: Option<Symbol>) {
272 self.miri_unleashed_features.lock().push((span, feature_gate));
275 fn check_miri_unleashed_features(&self) {
276 let unleashed_features = self.miri_unleashed_features.lock();
277 if !unleashed_features.is_empty() {
278 let mut must_err = false;
279 // Create a diagnostic pointing at where things got unleashed.
280 let mut diag = self.struct_warn("skipping const checks");
281 for &(span, feature_gate) in unleashed_features.iter() {
282 // FIXME: `span_label` doesn't do anything, so we use "help" as a hack.
283 if let Some(feature_gate) = feature_gate {
284 diag.span_help(span, &format!("skipping check for `{}` feature", feature_gate));
285 // The unleash flag must *not* be used to just "hack around" feature gates.
288 diag.span_help(span, "skipping check that does not even have a feature gate");
292 // If we should err, make sure we did.
293 if must_err && !self.has_errors() {
294 // We have skipped a feature gate, and not run into other errors... reject.
296 "`-Zunleash-the-miri-inside-of-you` may not be used to circumvent feature \
297 gates, except when testing error paths in the CTFE engine",
303 /// Invoked all the way at the end to finish off diagnostics printing.
304 pub fn finish_diagnostics(&self, registry: &Registry) {
305 self.check_miri_unleashed_features();
306 self.diagnostic().print_error_count(registry);
307 self.emit_future_breakage();
310 fn emit_future_breakage(&self) {
311 if !self.opts.debugging_opts.emit_future_incompat_report {
315 let diags = self.diagnostic().take_future_breakage_diagnostics();
316 if diags.is_empty() {
319 self.parse_sess.span_diagnostic.emit_future_breakage_report(diags);
322 pub fn local_stable_crate_id(&self) -> StableCrateId {
323 self.stable_crate_id.get().copied().unwrap()
326 pub fn crate_types(&self) -> &[CrateType] {
327 self.crate_types.get().unwrap().as_slice()
330 pub fn init_crate_types(&self, crate_types: Vec<CrateType>) {
331 self.crate_types.set(crate_types).expect("`crate_types` was initialized twice")
334 pub fn struct_span_warn<S: Into<MultiSpan>>(&self, sp: S, msg: &str) -> DiagnosticBuilder<'_> {
335 self.diagnostic().struct_span_warn(sp, msg)
337 pub fn struct_span_force_warn<S: Into<MultiSpan>>(
341 ) -> DiagnosticBuilder<'_> {
342 self.diagnostic().struct_span_force_warn(sp, msg)
344 pub fn struct_span_warn_with_code<S: Into<MultiSpan>>(
349 ) -> DiagnosticBuilder<'_> {
350 self.diagnostic().struct_span_warn_with_code(sp, msg, code)
352 pub fn struct_warn(&self, msg: &str) -> DiagnosticBuilder<'_> {
353 self.diagnostic().struct_warn(msg)
355 pub fn struct_force_warn(&self, msg: &str) -> DiagnosticBuilder<'_> {
356 self.diagnostic().struct_force_warn(msg)
358 pub fn struct_span_allow<S: Into<MultiSpan>>(&self, sp: S, msg: &str) -> DiagnosticBuilder<'_> {
359 self.diagnostic().struct_span_allow(sp, msg)
361 pub fn struct_allow(&self, msg: &str) -> DiagnosticBuilder<'_> {
362 self.diagnostic().struct_allow(msg)
364 pub fn struct_span_err<S: Into<MultiSpan>>(&self, sp: S, msg: &str) -> DiagnosticBuilder<'_> {
365 self.diagnostic().struct_span_err(sp, msg)
367 pub fn struct_span_err_with_code<S: Into<MultiSpan>>(
372 ) -> DiagnosticBuilder<'_> {
373 self.diagnostic().struct_span_err_with_code(sp, msg, code)
375 // FIXME: This method should be removed (every error should have an associated error code).
376 pub fn struct_err(&self, msg: &str) -> DiagnosticBuilder<'_> {
377 self.diagnostic().struct_err(msg)
379 pub fn struct_err_with_code(&self, msg: &str, code: DiagnosticId) -> DiagnosticBuilder<'_> {
380 self.diagnostic().struct_err_with_code(msg, code)
382 pub fn struct_span_fatal<S: Into<MultiSpan>>(&self, sp: S, msg: &str) -> DiagnosticBuilder<'_> {
383 self.diagnostic().struct_span_fatal(sp, msg)
385 pub fn struct_span_fatal_with_code<S: Into<MultiSpan>>(
390 ) -> DiagnosticBuilder<'_> {
391 self.diagnostic().struct_span_fatal_with_code(sp, msg, code)
393 pub fn struct_fatal(&self, msg: &str) -> DiagnosticBuilder<'_> {
394 self.diagnostic().struct_fatal(msg)
397 pub fn span_fatal<S: Into<MultiSpan>>(&self, sp: S, msg: &str) -> ! {
398 self.diagnostic().span_fatal(sp, msg)
400 pub fn span_fatal_with_code<S: Into<MultiSpan>>(
406 self.diagnostic().span_fatal_with_code(sp, msg, code)
408 pub fn fatal(&self, msg: &str) -> ! {
409 self.diagnostic().fatal(msg).raise()
411 pub fn span_err_or_warn<S: Into<MultiSpan>>(&self, is_warning: bool, sp: S, msg: &str) {
413 self.span_warn(sp, msg);
415 self.span_err(sp, msg);
418 pub fn span_err<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
419 self.diagnostic().span_err(sp, msg)
421 pub fn span_err_with_code<S: Into<MultiSpan>>(&self, sp: S, msg: &str, code: DiagnosticId) {
422 self.diagnostic().span_err_with_code(sp, &msg, code)
424 pub fn err(&self, msg: &str) {
425 self.diagnostic().err(msg)
427 pub fn emit_err<'a>(&'a self, err: impl SessionDiagnostic<'a>) {
428 err.into_diagnostic(self).emit()
431 pub fn err_count(&self) -> usize {
432 self.diagnostic().err_count()
434 pub fn has_errors(&self) -> bool {
435 self.diagnostic().has_errors()
437 pub fn has_errors_or_delayed_span_bugs(&self) -> bool {
438 self.diagnostic().has_errors_or_delayed_span_bugs()
440 pub fn abort_if_errors(&self) {
441 self.diagnostic().abort_if_errors();
443 pub fn compile_status(&self) -> Result<(), ErrorReported> {
444 if self.has_errors() {
445 self.diagnostic().emit_stashed_diagnostics();
451 // FIXME(matthewjasper) Remove this method, it should never be needed.
452 pub fn track_errors<F, T>(&self, f: F) -> Result<T, ErrorReported>
456 let old_count = self.err_count();
458 let errors = self.err_count() - old_count;
459 if errors == 0 { Ok(result) } else { Err(ErrorReported) }
461 pub fn span_warn<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
462 self.diagnostic().span_warn(sp, msg)
464 pub fn span_warn_with_code<S: Into<MultiSpan>>(&self, sp: S, msg: &str, code: DiagnosticId) {
465 self.diagnostic().span_warn_with_code(sp, msg, code)
467 pub fn warn(&self, msg: &str) {
468 self.diagnostic().warn(msg)
470 /// Delay a span_bug() call until abort_if_errors()
472 pub fn delay_span_bug<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
473 self.diagnostic().delay_span_bug(sp, msg)
476 /// Used for code paths of expensive computations that should only take place when
477 /// warnings or errors are emitted. If no messages are emitted ("good path"), then
478 /// it's likely a bug.
479 pub fn delay_good_path_bug(&self, msg: &str) {
480 if self.opts.debugging_opts.print_type_sizes
481 || self.opts.debugging_opts.query_dep_graph
482 || self.opts.debugging_opts.dump_mir.is_some()
483 || self.opts.debugging_opts.unpretty.is_some()
484 || self.opts.output_types.contains_key(&OutputType::Mir)
485 || std::env::var_os("RUSTC_LOG").is_some()
490 self.diagnostic().delay_good_path_bug(msg)
493 pub fn note_without_error(&self, msg: &str) {
494 self.diagnostic().note_without_error(msg)
496 pub fn span_note_without_error<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
497 self.diagnostic().span_note_without_error(sp, msg)
499 pub fn struct_note_without_error(&self, msg: &str) -> DiagnosticBuilder<'_> {
500 self.diagnostic().struct_note_without_error(msg)
504 pub fn diagnostic(&self) -> &rustc_errors::Handler {
505 &self.parse_sess.span_diagnostic
508 /// Analogous to calling methods on the given `DiagnosticBuilder`, but
509 /// deduplicates on lint ID, span (if any), and message for this `Session`
510 fn diag_once<'a, 'b>(
512 diag_builder: &'b mut DiagnosticBuilder<'a>,
513 method: DiagnosticBuilderMethod,
514 msg_id: DiagnosticMessageId,
516 span_maybe: Option<Span>,
518 let id_span_message = (msg_id, span_maybe, message.to_owned());
519 let fresh = self.one_time_diagnostics.borrow_mut().insert(id_span_message);
522 DiagnosticBuilderMethod::Note => {
523 diag_builder.note(message);
525 DiagnosticBuilderMethod::SpanNote => {
526 let span = span_maybe.expect("`span_note` needs a span");
527 diag_builder.span_note(span, message);
533 pub fn diag_span_note_once<'a, 'b>(
535 diag_builder: &'b mut DiagnosticBuilder<'a>,
536 msg_id: DiagnosticMessageId,
542 DiagnosticBuilderMethod::SpanNote,
549 pub fn diag_note_once<'a, 'b>(
551 diag_builder: &'b mut DiagnosticBuilder<'a>,
552 msg_id: DiagnosticMessageId,
555 self.diag_once(diag_builder, DiagnosticBuilderMethod::Note, msg_id, message, None);
559 pub fn source_map(&self) -> &SourceMap {
560 self.parse_sess.source_map()
562 pub fn verbose(&self) -> bool {
563 self.opts.debugging_opts.verbose
565 pub fn time_passes(&self) -> bool {
566 self.opts.debugging_opts.time_passes || self.opts.debugging_opts.time
568 pub fn instrument_mcount(&self) -> bool {
569 self.opts.debugging_opts.instrument_mcount
571 pub fn time_llvm_passes(&self) -> bool {
572 self.opts.debugging_opts.time_llvm_passes
574 pub fn meta_stats(&self) -> bool {
575 self.opts.debugging_opts.meta_stats
577 pub fn asm_comments(&self) -> bool {
578 self.opts.debugging_opts.asm_comments
580 pub fn verify_llvm_ir(&self) -> bool {
581 self.opts.debugging_opts.verify_llvm_ir || option_env!("RUSTC_VERIFY_LLVM_IR").is_some()
583 pub fn print_llvm_passes(&self) -> bool {
584 self.opts.debugging_opts.print_llvm_passes
586 pub fn binary_dep_depinfo(&self) -> bool {
587 self.opts.debugging_opts.binary_dep_depinfo
589 pub fn mir_opt_level(&self) -> usize {
593 .unwrap_or_else(|| if self.opts.optimize != config::OptLevel::No { 2 } else { 1 })
596 /// Gets the features enabled for the current compilation session.
597 /// DO NOT USE THIS METHOD if there is a TyCtxt available, as it circumvents
598 /// dependency tracking. Use tcx.features() instead.
600 pub fn features_untracked(&self) -> &rustc_feature::Features {
601 self.features.get().unwrap()
604 pub fn init_features(&self, features: rustc_feature::Features) {
605 match self.features.set(features) {
607 Err(_) => panic!("`features` was initialized twice"),
611 pub fn init_lint_store(&self, lint_store: Lrc<dyn SessionLintStore>) {
615 .expect("`lint_store` was initialized twice");
618 /// Calculates the flavor of LTO to use for this compilation.
619 pub fn lto(&self) -> config::Lto {
620 // If our target has codegen requirements ignore the command line
621 if self.target.requires_lto {
622 return config::Lto::Fat;
625 // If the user specified something, return that. If they only said `-C
626 // lto` and we've for whatever reason forced off ThinLTO via the CLI,
627 // then ensure we can't use a ThinLTO.
628 match self.opts.cg.lto {
629 config::LtoCli::Unspecified => {
630 // The compiler was invoked without the `-Clto` flag. Fall
631 // through to the default handling
633 config::LtoCli::No => {
634 // The user explicitly opted out of any kind of LTO
635 return config::Lto::No;
637 config::LtoCli::Yes | config::LtoCli::Fat | config::LtoCli::NoParam => {
638 // All of these mean fat LTO
639 return config::Lto::Fat;
641 config::LtoCli::Thin => {
642 return if self.opts.cli_forced_thinlto_off {
650 // Ok at this point the target doesn't require anything and the user
651 // hasn't asked for anything. Our next decision is whether or not
652 // we enable "auto" ThinLTO where we use multiple codegen units and
653 // then do ThinLTO over those codegen units. The logic below will
654 // either return `No` or `ThinLocal`.
656 // If processing command line options determined that we're incompatible
657 // with ThinLTO (e.g., `-C lto --emit llvm-ir`) then return that option.
658 if self.opts.cli_forced_thinlto_off {
659 return config::Lto::No;
662 // If `-Z thinlto` specified process that, but note that this is mostly
663 // a deprecated option now that `-C lto=thin` exists.
664 if let Some(enabled) = self.opts.debugging_opts.thinlto {
666 return config::Lto::ThinLocal;
668 return config::Lto::No;
672 // If there's only one codegen unit and LTO isn't enabled then there's
673 // no need for ThinLTO so just return false.
674 if self.codegen_units() == 1 {
675 return config::Lto::No;
678 // Now we're in "defaults" territory. By default we enable ThinLTO for
679 // optimized compiles (anything greater than O0).
680 match self.opts.optimize {
681 config::OptLevel::No => config::Lto::No,
682 _ => config::Lto::ThinLocal,
686 /// Returns the panic strategy for this compile session. If the user explicitly selected one
687 /// using '-C panic', use that, otherwise use the panic strategy defined by the target.
688 pub fn panic_strategy(&self) -> PanicStrategy {
689 self.opts.cg.panic.unwrap_or(self.target.panic_strategy)
691 pub fn fewer_names(&self) -> bool {
692 if let Some(fewer_names) = self.opts.debugging_opts.fewer_names {
695 let more_names = self.opts.output_types.contains_key(&OutputType::LlvmAssembly)
696 || self.opts.output_types.contains_key(&OutputType::Bitcode)
697 // AddressSanitizer and MemorySanitizer use alloca name when reporting an issue.
698 || self.opts.debugging_opts.sanitizer.intersects(SanitizerSet::ADDRESS | SanitizerSet::MEMORY);
703 pub fn unstable_options(&self) -> bool {
704 self.opts.debugging_opts.unstable_options
706 pub fn is_nightly_build(&self) -> bool {
707 self.opts.unstable_features.is_nightly_build()
709 pub fn overflow_checks(&self) -> bool {
713 .or(self.opts.debugging_opts.force_overflow_checks)
714 .unwrap_or(self.opts.debug_assertions)
717 /// Check whether this compile session and crate type use static crt.
718 pub fn crt_static(&self, crate_type: Option<CrateType>) -> bool {
719 if !self.target.crt_static_respected {
720 // If the target does not opt in to crt-static support, use its default.
721 return self.target.crt_static_default;
724 let requested_features = self.opts.cg.target_feature.split(',');
725 let found_negative = requested_features.clone().any(|r| r == "-crt-static");
726 let found_positive = requested_features.clone().any(|r| r == "+crt-static");
728 if found_positive || found_negative {
730 } else if crate_type == Some(CrateType::ProcMacro)
731 || crate_type == None && self.opts.crate_types.contains(&CrateType::ProcMacro)
733 // FIXME: When crate_type is not available,
734 // we use compiler options to determine the crate_type.
735 // We can't check `#![crate_type = "proc-macro"]` here.
738 self.target.crt_static_default
742 pub fn relocation_model(&self) -> RelocModel {
743 self.opts.cg.relocation_model.unwrap_or(self.target.relocation_model)
746 pub fn code_model(&self) -> Option<CodeModel> {
747 self.opts.cg.code_model.or(self.target.code_model)
750 pub fn tls_model(&self) -> TlsModel {
751 self.opts.debugging_opts.tls_model.unwrap_or(self.target.tls_model)
754 pub fn is_wasi_reactor(&self) -> bool {
755 self.target.options.os == "wasi"
757 self.opts.debugging_opts.wasi_exec_model,
758 Some(config::WasiExecModel::Reactor)
762 pub fn split_debuginfo(&self) -> SplitDebuginfo {
763 self.opts.cg.split_debuginfo.unwrap_or(self.target.split_debuginfo)
766 pub fn target_can_use_split_dwarf(&self) -> bool {
767 !self.target.is_like_windows && !self.target.is_like_osx
770 pub fn must_emit_unwind_tables(&self) -> bool {
771 // This is used to control the emission of the `uwtable` attribute on
774 // Unwind tables are needed when compiling with `-C panic=unwind`, but
775 // LLVM won't omit unwind tables unless the function is also marked as
776 // `nounwind`, so users are allowed to disable `uwtable` emission.
777 // Historically rustc always emits `uwtable` attributes by default, so
778 // even they can be disabled, they're still emitted by default.
780 // On some targets (including windows), however, exceptions include
781 // other events such as illegal instructions, segfaults, etc. This means
782 // that on Windows we end up still needing unwind tables even if the `-C
783 // panic=abort` flag is passed.
785 // You can also find more info on why Windows needs unwind tables in:
786 // https://bugzilla.mozilla.org/show_bug.cgi?id=1302078
788 // If a target requires unwind tables, then they must be emitted.
789 // Otherwise, we can defer to the `-C force-unwind-tables=<yes/no>`
790 // value, if it is provided, or disable them, if not.
791 self.target.requires_uwtable
792 || self.opts.cg.force_unwind_tables.unwrap_or(
793 self.panic_strategy() == PanicStrategy::Unwind || self.target.default_uwtable,
797 /// Returns the symbol name for the registrar function,
798 /// given the crate `Svh` and the function `DefIndex`.
799 pub fn generate_plugin_registrar_symbol(&self, stable_crate_id: StableCrateId) -> String {
800 format!("__rustc_plugin_registrar_{:08x}__", stable_crate_id.to_u64())
803 pub fn generate_proc_macro_decls_symbol(&self, stable_crate_id: StableCrateId) -> String {
804 format!("__rustc_proc_macro_decls_{:08x}__", stable_crate_id.to_u64())
807 pub fn target_filesearch(&self, kind: PathKind) -> filesearch::FileSearch<'_> {
808 filesearch::FileSearch::new(
810 self.opts.target_triple.triple(),
811 &self.opts.search_paths,
812 // `target_tlib_path == None` means it's the same as `host_tlib_path`.
813 self.target_tlib_path.as_ref().unwrap_or(&self.host_tlib_path),
817 pub fn host_filesearch(&self, kind: PathKind) -> filesearch::FileSearch<'_> {
818 filesearch::FileSearch::new(
820 config::host_triple(),
821 &self.opts.search_paths,
822 &self.host_tlib_path,
827 pub fn init_incr_comp_session(
829 session_dir: PathBuf,
830 lock_file: flock::Lock,
831 load_dep_graph: bool,
833 let mut incr_comp_session = self.incr_comp_session.borrow_mut();
835 if let IncrCompSession::NotInitialized = *incr_comp_session {
837 panic!("Trying to initialize IncrCompSession `{:?}`", *incr_comp_session)
841 IncrCompSession::Active { session_directory: session_dir, lock_file, load_dep_graph };
844 pub fn finalize_incr_comp_session(&self, new_directory_path: PathBuf) {
845 let mut incr_comp_session = self.incr_comp_session.borrow_mut();
847 if let IncrCompSession::Active { .. } = *incr_comp_session {
849 panic!("trying to finalize `IncrCompSession` `{:?}`", *incr_comp_session);
852 // Note: this will also drop the lock file, thus unlocking the directory.
853 *incr_comp_session = IncrCompSession::Finalized { session_directory: new_directory_path };
856 pub fn mark_incr_comp_session_as_invalid(&self) {
857 let mut incr_comp_session = self.incr_comp_session.borrow_mut();
859 let session_directory = match *incr_comp_session {
860 IncrCompSession::Active { ref session_directory, .. } => session_directory.clone(),
861 IncrCompSession::InvalidBecauseOfErrors { .. } => return,
862 _ => panic!("trying to invalidate `IncrCompSession` `{:?}`", *incr_comp_session),
865 // Note: this will also drop the lock file, thus unlocking the directory.
866 *incr_comp_session = IncrCompSession::InvalidBecauseOfErrors { session_directory };
869 pub fn incr_comp_session_dir(&self) -> cell::Ref<'_, PathBuf> {
870 let incr_comp_session = self.incr_comp_session.borrow();
871 cell::Ref::map(incr_comp_session, |incr_comp_session| match *incr_comp_session {
872 IncrCompSession::NotInitialized => panic!(
873 "trying to get session directory from `IncrCompSession`: {:?}",
876 IncrCompSession::Active { ref session_directory, .. }
877 | IncrCompSession::Finalized { ref session_directory }
878 | IncrCompSession::InvalidBecauseOfErrors { ref session_directory } => {
884 pub fn incr_comp_session_dir_opt(&self) -> Option<cell::Ref<'_, PathBuf>> {
885 self.opts.incremental.as_ref().map(|_| self.incr_comp_session_dir())
888 pub fn print_perf_stats(&self) {
890 "Total time spent computing symbol hashes: {}",
891 duration_to_secs_str(*self.perf_stats.symbol_hash_time.lock())
894 "Total queries canonicalized: {}",
895 self.perf_stats.queries_canonicalized.load(Ordering::Relaxed)
898 "normalize_generic_arg_after_erasing_regions: {}",
899 self.perf_stats.normalize_generic_arg_after_erasing_regions.load(Ordering::Relaxed)
902 "normalize_projection_ty: {}",
903 self.perf_stats.normalize_projection_ty.load(Ordering::Relaxed)
907 /// We want to know if we're allowed to do an optimization for crate foo from -z fuel=foo=n.
908 /// This expends fuel if applicable, and records fuel if applicable.
909 pub fn consider_optimizing<T: Fn() -> String>(&self, crate_name: &str, msg: T) -> bool {
911 if let Some(ref c) = self.optimization_fuel_crate {
913 assert_eq!(self.threads(), 1);
914 let mut fuel = self.optimization_fuel.lock();
915 ret = fuel.remaining != 0;
916 if fuel.remaining == 0 && !fuel.out_of_fuel {
917 self.warn(&format!("optimization-fuel-exhausted: {}", msg()));
918 fuel.out_of_fuel = true;
919 } else if fuel.remaining > 0 {
924 if let Some(ref c) = self.print_fuel_crate {
926 assert_eq!(self.threads(), 1);
927 self.print_fuel.fetch_add(1, SeqCst);
933 /// Returns the number of query threads that should be used for this
935 pub fn threads(&self) -> usize {
936 self.opts.debugging_opts.threads
939 /// Returns the number of codegen units that should be used for this
941 pub fn codegen_units(&self) -> usize {
942 if let Some(n) = self.opts.cli_forced_codegen_units {
945 if let Some(n) = self.target.default_codegen_units {
949 // If incremental compilation is turned on, we default to a high number
950 // codegen units in order to reduce the "collateral damage" small
952 if self.opts.incremental.is_some() {
956 // Why is 16 codegen units the default all the time?
958 // The main reason for enabling multiple codegen units by default is to
959 // leverage the ability for the codegen backend to do codegen and
960 // optimization in parallel. This allows us, especially for large crates, to
961 // make good use of all available resources on the machine once we've
962 // hit that stage of compilation. Large crates especially then often
963 // take a long time in codegen/optimization and this helps us amortize that
966 // Note that a high number here doesn't mean that we'll be spawning a
967 // large number of threads in parallel. The backend of rustc contains
968 // global rate limiting through the `jobserver` crate so we'll never
969 // overload the system with too much work, but rather we'll only be
970 // optimizing when we're otherwise cooperating with other instances of
973 // Rather a high number here means that we should be able to keep a lot
974 // of idle cpus busy. By ensuring that no codegen unit takes *too* long
975 // to build we'll be guaranteed that all cpus will finish pretty closely
976 // to one another and we should make relatively optimal use of system
979 // Note that the main cost of codegen units is that it prevents LLVM
980 // from inlining across codegen units. Users in general don't have a lot
981 // of control over how codegen units are split up so it's our job in the
982 // compiler to ensure that undue performance isn't lost when using
983 // codegen units (aka we can't require everyone to slap `#[inline]` on
986 // If we're compiling at `-O0` then the number doesn't really matter too
987 // much because performance doesn't matter and inlining is ok to lose.
988 // In debug mode we just want to try to guarantee that no cpu is stuck
989 // doing work that could otherwise be farmed to others.
991 // In release mode, however (O1 and above) performance does indeed
992 // matter! To recover the loss in performance due to inlining we'll be
993 // enabling ThinLTO by default (the function for which is just below).
994 // This will ensure that we recover any inlining wins we otherwise lost
995 // through codegen unit partitioning.
999 // Ok that's a lot of words but the basic tl;dr; is that we want a high
1000 // number here -- but not too high. Additionally we're "safe" to have it
1001 // always at the same number at all optimization levels.
1003 // As a result 16 was chosen here! Mostly because it was a power of 2
1004 // and most benchmarks agreed it was roughly a local optimum. Not very
1009 pub fn teach(&self, code: &DiagnosticId) -> bool {
1010 self.opts.debugging_opts.teach && self.diagnostic().must_teach(code)
1013 pub fn rust_2015(&self) -> bool {
1014 self.opts.edition == Edition::Edition2015
1017 /// Are we allowed to use features from the Rust 2018 edition?
1018 pub fn rust_2018(&self) -> bool {
1019 self.opts.edition >= Edition::Edition2018
1022 /// Are we allowed to use features from the Rust 2021 edition?
1023 pub fn rust_2021(&self) -> bool {
1024 self.opts.edition >= Edition::Edition2021
1027 pub fn edition(&self) -> Edition {
1031 /// Returns `true` if we cannot skip the PLT for shared library calls.
1032 pub fn needs_plt(&self) -> bool {
1033 // Check if the current target usually needs PLT to be enabled.
1034 // The user can use the command line flag to override it.
1035 let needs_plt = self.target.needs_plt;
1037 let dbg_opts = &self.opts.debugging_opts;
1039 let relro_level = dbg_opts.relro_level.unwrap_or(self.target.relro_level);
1041 // Only enable this optimization by default if full relro is also enabled.
1042 // In this case, lazy binding was already unavailable, so nothing is lost.
1043 // This also ensures `-Wl,-z,now` is supported by the linker.
1044 let full_relro = RelroLevel::Full == relro_level;
1046 // If user didn't explicitly forced us to use / skip the PLT,
1047 // then try to skip it where possible.
1048 dbg_opts.plt.unwrap_or(needs_plt || !full_relro)
1051 /// Checks if LLVM lifetime markers should be emitted.
1052 pub fn emit_lifetime_markers(&self) -> bool {
1053 self.opts.optimize != config::OptLevel::No
1054 // AddressSanitizer uses lifetimes to detect use after scope bugs.
1055 // MemorySanitizer uses lifetimes to detect use of uninitialized stack variables.
1056 // HWAddressSanitizer will use lifetimes to detect use after scope bugs in the future.
1057 || self.opts.debugging_opts.sanitizer.intersects(SanitizerSet::ADDRESS | SanitizerSet::MEMORY | SanitizerSet::HWADDRESS)
1060 pub fn link_dead_code(&self) -> bool {
1061 self.opts.cg.link_dead_code.unwrap_or(false)
1064 pub fn instrument_coverage(&self) -> bool {
1065 self.opts.debugging_opts.instrument_coverage.unwrap_or(config::InstrumentCoverage::Off)
1066 != config::InstrumentCoverage::Off
1069 pub fn instrument_coverage_except_unused_generics(&self) -> bool {
1070 self.opts.debugging_opts.instrument_coverage.unwrap_or(config::InstrumentCoverage::Off)
1071 == config::InstrumentCoverage::ExceptUnusedGenerics
1074 pub fn instrument_coverage_except_unused_functions(&self) -> bool {
1075 self.opts.debugging_opts.instrument_coverage.unwrap_or(config::InstrumentCoverage::Off)
1076 == config::InstrumentCoverage::ExceptUnusedFunctions
1079 pub fn mark_attr_known(&self, attr: &Attribute) {
1080 self.known_attrs.lock().mark(attr)
1083 pub fn is_attr_known(&self, attr: &Attribute) -> bool {
1084 self.known_attrs.lock().is_marked(attr)
1087 pub fn mark_attr_used(&self, attr: &Attribute) {
1088 self.used_attrs.lock().mark(attr)
1091 pub fn is_attr_used(&self, attr: &Attribute) -> bool {
1092 self.used_attrs.lock().is_marked(attr)
1095 /// Returns `true` if the attribute's path matches the argument. If it
1096 /// matches, then the attribute is marked as used.
1098 /// This method should only be used by rustc, other tools can use
1099 /// `Attribute::has_name` instead, because only rustc is supposed to report
1100 /// the `unused_attributes` lint. (`MetaItem` and `NestedMetaItem` are
1101 /// produced by lowering an `Attribute` and don't have identity, so they
1102 /// only have the `has_name` method, and you need to mark the original
1103 /// `Attribute` as used when necessary.)
1104 pub fn check_name(&self, attr: &Attribute, name: Symbol) -> bool {
1105 let matches = attr.has_name(name);
1107 self.mark_attr_used(attr);
1112 pub fn is_proc_macro_attr(&self, attr: &Attribute) -> bool {
1113 [sym::proc_macro, sym::proc_macro_attribute, sym::proc_macro_derive]
1115 .any(|kind| self.check_name(attr, *kind))
1118 pub fn contains_name(&self, attrs: &[Attribute], name: Symbol) -> bool {
1119 attrs.iter().any(|item| self.check_name(item, name))
1122 pub fn find_by_name<'a>(
1124 attrs: &'a [Attribute],
1126 ) -> Option<&'a Attribute> {
1127 attrs.iter().find(|attr| self.check_name(attr, name))
1130 pub fn filter_by_name<'a>(
1132 attrs: &'a [Attribute],
1134 ) -> impl Iterator<Item = &'a Attribute> {
1135 attrs.iter().filter(move |attr| self.check_name(attr, name))
1138 pub fn first_attr_value_str_by_name(
1140 attrs: &[Attribute],
1142 ) -> Option<Symbol> {
1143 attrs.iter().find(|at| self.check_name(at, name)).and_then(|at| at.value_str())
1148 sopts: &config::Options,
1149 registry: rustc_errors::registry::Registry,
1150 source_map: Lrc<SourceMap>,
1151 emitter_dest: Option<Box<dyn Write + Send>>,
1152 ) -> Box<dyn Emitter + sync::Send> {
1153 let macro_backtrace = sopts.debugging_opts.macro_backtrace;
1154 match (sopts.error_format, emitter_dest) {
1155 (config::ErrorOutputType::HumanReadable(kind), dst) => {
1156 let (short, color_config) = kind.unzip();
1158 if let HumanReadableErrorType::AnnotateSnippet(_) = kind {
1160 AnnotateSnippetEmitterWriter::new(Some(source_map), short, macro_backtrace);
1161 Box::new(emitter.ui_testing(sopts.debugging_opts.ui_testing))
1163 let emitter = match dst {
1164 None => EmitterWriter::stderr(
1168 sopts.debugging_opts.teach,
1169 sopts.debugging_opts.terminal_width,
1172 Some(dst) => EmitterWriter::new(
1176 false, // no teach messages when writing to a buffer
1177 false, // no colors when writing to a buffer
1178 None, // no terminal width
1182 Box::new(emitter.ui_testing(sopts.debugging_opts.ui_testing))
1185 (config::ErrorOutputType::Json { pretty, json_rendered }, None) => Box::new(
1186 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(
1203 sopts.debugging_opts.terminal_width,
1206 .ui_testing(sopts.debugging_opts.ui_testing),
1211 pub enum DiagnosticOutput {
1213 Raw(Box<dyn Write + Send>),
1216 pub fn build_session(
1217 sopts: config::Options,
1218 local_crate_source_file: Option<PathBuf>,
1219 registry: rustc_errors::registry::Registry,
1220 diagnostics_output: DiagnosticOutput,
1221 driver_lint_caps: FxHashMap<lint::LintId, lint::Level>,
1222 file_loader: Option<Box<dyn FileLoader + Send + Sync + 'static>>,
1223 target_override: Option<Target>,
1225 // FIXME: This is not general enough to make the warning lint completely override
1226 // normal diagnostic warnings, since the warning lint can also be denied and changed
1227 // later via the source code.
1228 let warnings_allow = sopts
1231 .filter(|&&(ref key, _)| *key == "warnings")
1232 .map(|&(_, ref level)| *level == lint::Allow)
1235 let cap_lints_allow = sopts.lint_cap.map_or(false, |cap| cap == lint::Allow);
1236 let can_emit_warnings = !(warnings_allow || cap_lints_allow);
1238 let write_dest = match diagnostics_output {
1239 DiagnosticOutput::Default => None,
1240 DiagnosticOutput::Raw(write) => Some(write),
1243 let sysroot = match &sopts.maybe_sysroot {
1244 Some(sysroot) => sysroot.clone(),
1245 None => filesearch::get_or_default_sysroot(),
1248 let target_cfg = config::build_target_config(&sopts, target_override, &sysroot);
1249 let host_triple = TargetTriple::from_triple(config::host_triple());
1250 let (host, target_warnings) = Target::search(&host_triple, &sysroot).unwrap_or_else(|e| {
1251 early_error(sopts.error_format, &format!("Error loading host specification: {}", e))
1253 for warning in target_warnings.warning_messages() {
1254 early_warn(sopts.error_format, &warning)
1257 let loader = file_loader.unwrap_or_else(|| Box::new(RealFileLoader));
1258 let hash_kind = sopts.debugging_opts.src_hash_algorithm.unwrap_or_else(|| {
1259 if target_cfg.is_like_msvc {
1260 SourceFileHashAlgorithm::Sha1
1262 SourceFileHashAlgorithm::Md5
1265 let source_map = Lrc::new(SourceMap::with_file_loader_and_hash_kind(
1267 sopts.file_path_mapping(),
1270 let emitter = default_emitter(&sopts, registry, source_map.clone(), write_dest);
1272 let span_diagnostic = rustc_errors::Handler::with_emitter_and_flags(
1274 sopts.debugging_opts.diagnostic_handler_flags(can_emit_warnings),
1277 let self_profiler = if let SwitchWithOptPath::Enabled(ref d) = sopts.debugging_opts.self_profile
1280 if let Some(ref directory) = d { directory } else { std::path::Path::new(".") };
1282 let profiler = SelfProfiler::new(
1284 sopts.crate_name.as_deref(),
1285 &sopts.debugging_opts.self_profile_events,
1288 Ok(profiler) => Some(Arc::new(profiler)),
1290 early_warn(sopts.error_format, &format!("failed to create profiler: {}", e));
1298 let mut parse_sess = ParseSess::with_span_handler(span_diagnostic, source_map);
1299 parse_sess.assume_incomplete_release = sopts.debugging_opts.assume_incomplete_release;
1301 let host_triple = config::host_triple();
1302 let target_triple = sopts.target_triple.triple();
1303 let host_tlib_path = SearchPath::from_sysroot_and_triple(&sysroot, host_triple);
1304 let target_tlib_path = if host_triple == target_triple {
1307 Some(SearchPath::from_sysroot_and_triple(&sysroot, target_triple))
1310 let file_path_mapping = sopts.file_path_mapping();
1312 let local_crate_source_file =
1313 local_crate_source_file.map(|path| file_path_mapping.map_prefix(path).0);
1315 let optimization_fuel_crate = sopts.debugging_opts.fuel.as_ref().map(|i| i.0.clone());
1316 let optimization_fuel = Lock::new(OptimizationFuel {
1317 remaining: sopts.debugging_opts.fuel.as_ref().map_or(0, |i| i.1),
1320 let print_fuel_crate = sopts.debugging_opts.print_fuel.clone();
1321 let print_fuel = AtomicU64::new(0);
1323 let working_dir = env::current_dir().unwrap_or_else(|e| {
1324 parse_sess.span_diagnostic.fatal(&format!("Current directory is invalid: {}", e)).raise()
1326 let (path, remapped) = file_path_mapping.map_prefix(working_dir.clone());
1327 let working_dir = if remapped {
1328 RealFileName::Remapped { local_path: Some(working_dir), virtual_name: path }
1330 RealFileName::LocalPath(path)
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,
1364 one_time_diagnostics: Default::default(),
1365 crate_types: OnceCell::new(),
1366 stable_crate_id: OnceCell::new(),
1367 features: OnceCell::new(),
1368 lint_store: OnceCell::new(),
1369 incr_comp_session: OneThread::new(RefCell::new(IncrCompSession::NotInitialized)),
1372 perf_stats: PerfStats {
1373 symbol_hash_time: Lock::new(Duration::from_secs(0)),
1374 queries_canonicalized: AtomicUsize::new(0),
1375 normalize_generic_arg_after_erasing_regions: AtomicUsize::new(0),
1376 normalize_projection_ty: AtomicUsize::new(0),
1378 code_stats: Default::default(),
1379 optimization_fuel_crate,
1383 jobserver: jobserver::client(),
1385 trait_methods_not_found: Lock::new(Default::default()),
1386 confused_type_with_std_module: Lock::new(Default::default()),
1387 system_library_path: OneThread::new(RefCell::new(Default::default())),
1389 miri_unleashed_features: Lock::new(Default::default()),
1391 target_features: FxHashSet::default(),
1392 known_attrs: Lock::new(MarkedAttrs::new()),
1393 used_attrs: Lock::new(MarkedAttrs::new()),
1394 if_let_suggestions: Default::default(),
1397 validate_commandline_args_with_session_available(&sess);
1402 // If it is useful to have a Session available already for validating a
1403 // commandline argument, you can do so here.
1404 fn validate_commandline_args_with_session_available(sess: &Session) {
1405 // Since we don't know if code in an rlib will be linked to statically or
1406 // dynamically downstream, rustc generates `__imp_` symbols that help linkers
1407 // on Windows deal with this lack of knowledge (#27438). Unfortunately,
1408 // these manually generated symbols confuse LLD when it tries to merge
1409 // bitcode during ThinLTO. Therefore we disallow dynamic linking on Windows
1410 // when compiling for LLD ThinLTO. This way we can validly just not generate
1411 // the `dllimport` attributes and `__imp_` symbols in that case.
1412 if sess.opts.cg.linker_plugin_lto.enabled()
1413 && sess.opts.cg.prefer_dynamic
1414 && sess.target.is_like_windows
1417 "Linker plugin based LTO is not supported together with \
1418 `-C prefer-dynamic` when targeting Windows-like targets",
1422 // Make sure that any given profiling data actually exists so LLVM can't
1423 // decide to silently skip PGO.
1424 if let Some(ref path) = sess.opts.cg.profile_use {
1427 "File `{}` passed to `-C profile-use` does not exist.",
1433 // Unwind tables cannot be disabled if the target requires them.
1434 if let Some(include_uwtables) = sess.opts.cg.force_unwind_tables {
1435 if sess.target.requires_uwtable && !include_uwtables {
1437 "target requires unwind tables, they cannot be disabled with \
1438 `-C force-unwind-tables=no`.",
1443 // Sanitizers can only be used on platforms that we know have working sanitizer codegen.
1444 let supported_sanitizers = sess.target.options.supported_sanitizers;
1445 let unsupported_sanitizers = sess.opts.debugging_opts.sanitizer - supported_sanitizers;
1446 match unsupported_sanitizers.into_iter().count() {
1449 .err(&format!("{} sanitizer is not supported for this target", unsupported_sanitizers)),
1450 _ => sess.err(&format!(
1451 "{} sanitizers are not supported for this target",
1452 unsupported_sanitizers
1455 // Cannot mix and match sanitizers.
1456 let mut sanitizer_iter = sess.opts.debugging_opts.sanitizer.into_iter();
1457 if let (Some(first), Some(second)) = (sanitizer_iter.next(), sanitizer_iter.next()) {
1458 sess.err(&format!("`-Zsanitizer={}` is incompatible with `-Zsanitizer={}`", first, second));
1461 // Cannot enable crt-static with sanitizers on Linux
1462 if sess.crt_static(None) && !sess.opts.debugging_opts.sanitizer.is_empty() {
1464 "Sanitizer is incompatible with statically linked libc, \
1465 disable it using `-C target-feature=-crt-static`",
1470 /// Holds data on the current incremental compilation session, if there is one.
1472 pub enum IncrCompSession {
1473 /// This is the state the session will be in until the incr. comp. dir is
1476 /// This is the state during which the session directory is private and can
1478 Active { session_directory: PathBuf, lock_file: flock::Lock, load_dep_graph: bool },
1479 /// This is the state after the session directory has been finalized. In this
1480 /// state, the contents of the directory must not be modified any more.
1481 Finalized { session_directory: PathBuf },
1482 /// This is an error state that is reached when some compilation error has
1483 /// occurred. It indicates that the contents of the session directory must
1484 /// not be used, since they might be invalid.
1485 InvalidBecauseOfErrors { session_directory: PathBuf },
1488 pub fn early_error_no_abort(output: config::ErrorOutputType, msg: &str) {
1489 let emitter: Box<dyn Emitter + sync::Send> = match output {
1490 config::ErrorOutputType::HumanReadable(kind) => {
1491 let (short, color_config) = kind.unzip();
1492 Box::new(EmitterWriter::stderr(color_config, None, short, false, None, false))
1494 config::ErrorOutputType::Json { pretty, json_rendered } => {
1495 Box::new(JsonEmitter::basic(pretty, json_rendered, None, false))
1498 let handler = rustc_errors::Handler::with_emitter(true, None, emitter);
1499 handler.struct_fatal(msg).emit();
1502 pub fn early_error(output: config::ErrorOutputType, msg: &str) -> ! {
1503 early_error_no_abort(output, msg);
1504 rustc_errors::FatalError.raise();
1507 pub fn early_warn(output: config::ErrorOutputType, msg: &str) {
1508 let emitter: Box<dyn Emitter + sync::Send> = match output {
1509 config::ErrorOutputType::HumanReadable(kind) => {
1510 let (short, color_config) = kind.unzip();
1511 Box::new(EmitterWriter::stderr(color_config, None, short, false, None, false))
1513 config::ErrorOutputType::Json { pretty, json_rendered } => {
1514 Box::new(JsonEmitter::basic(pretty, json_rendered, None, false))
1517 let handler = rustc_errors::Handler::with_emitter(true, None, emitter);
1518 handler.struct_warn(msg).emit();