1 //! Diagnostics creation and emission for `rustc`.
3 //! This module contains the code for creating and emitting diagnostics.
5 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
6 #![feature(drain_filter)]
7 #![feature(if_let_guard)]
8 #![feature(adt_const_params)]
9 #![feature(let_chains)]
11 #![feature(never_type)]
12 #![feature(result_option_inspect)]
13 #![feature(rustc_attrs)]
14 #![allow(incomplete_features)]
15 #![allow(rustc::potential_query_instability)]
18 extern crate rustc_macros;
23 pub use emitter::ColorConfig;
25 use rustc_lint_defs::LintExpectationId;
28 use emitter::{is_case_difference, Emitter, EmitterWriter};
29 use registry::Registry;
30 use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexMap};
31 use rustc_data_structures::stable_hasher::StableHasher;
32 use rustc_data_structures::sync::{self, Lock, Lrc};
33 use rustc_data_structures::AtomicRef;
34 pub use rustc_error_messages::{
35 fallback_fluent_bundle, fluent, fluent_bundle, DiagnosticMessage, FluentBundle,
36 LanguageIdentifier, LazyFallbackBundle, MultiSpan, SpanLabel, SubdiagnosticMessage,
37 DEFAULT_LOCALE_RESOURCES,
39 pub use rustc_lint_defs::{pluralize, Applicability};
40 use rustc_span::source_map::SourceMap;
41 use rustc_span::HashStableContext;
42 use rustc_span::{Loc, Span};
46 use std::num::NonZeroUsize;
49 use std::{error, fmt};
51 use termcolor::{Color, ColorSpec};
53 pub mod annotate_snippet_emitter_writer;
55 mod diagnostic_builder;
64 pub use snippet::Style;
66 pub type PResult<'a, T> = Result<T, DiagnosticBuilder<'a, ErrorGuaranteed>>;
68 // `PResult` is used a lot. Make sure it doesn't unintentionally get bigger.
69 // (See also the comment on `DiagnosticBuilder`'s `diagnostic` field.)
70 #[cfg(all(target_arch = "x86_64", target_pointer_width = "64"))]
71 rustc_data_structures::static_assert_size!(PResult<'_, ()>, 16);
72 #[cfg(all(target_arch = "x86_64", target_pointer_width = "64"))]
73 rustc_data_structures::static_assert_size!(PResult<'_, bool>, 24);
75 #[derive(Debug, PartialEq, Eq, Clone, Copy, Hash, Encodable, Decodable)]
76 pub enum SuggestionStyle {
77 /// Hide the suggested code when displaying this suggestion inline.
79 /// Always hide the suggested code but display the message.
81 /// Do not display this suggestion in the cli output, it is only meant for tools.
83 /// Always show the suggested code.
84 /// This will *not* show the code if the suggestion is inline *and* the suggested code is
87 /// Always show the suggested code independently.
91 impl SuggestionStyle {
92 fn hide_inline(&self) -> bool {
93 !matches!(*self, SuggestionStyle::ShowCode)
97 #[derive(Clone, Debug, PartialEq, Hash, Encodable, Decodable)]
98 pub struct CodeSuggestion {
99 /// Each substitute can have multiple variants due to multiple
100 /// applicable suggestions
102 /// `foo.bar` might be replaced with `a.b` or `x.y` by replacing
103 /// `foo` and `bar` on their own:
105 /// ```ignore (illustrative)
107 /// Substitution { parts: vec![(0..3, "a"), (4..7, "b")] },
108 /// Substitution { parts: vec![(0..3, "x"), (4..7, "y")] },
112 /// or by replacing the entire span:
114 /// ```ignore (illustrative)
116 /// Substitution { parts: vec![(0..7, "a.b")] },
117 /// Substitution { parts: vec![(0..7, "x.y")] },
120 pub substitutions: Vec<Substitution>,
121 pub msg: DiagnosticMessage,
122 /// Visual representation of this suggestion.
123 pub style: SuggestionStyle,
124 /// Whether or not the suggestion is approximate
126 /// Sometimes we may show suggestions with placeholders,
127 /// which are useful for users but not useful for
128 /// tools like rustfix
129 pub applicability: Applicability,
132 #[derive(Clone, Debug, PartialEq, Hash, Encodable, Decodable)]
133 /// See the docs on `CodeSuggestion::substitutions`
134 pub struct Substitution {
135 pub parts: Vec<SubstitutionPart>,
138 #[derive(Clone, Debug, PartialEq, Hash, Encodable, Decodable)]
139 pub struct SubstitutionPart {
144 /// Used to translate between `Span`s and byte positions within a single output line in highlighted
145 /// code of structured suggestions.
146 #[derive(Debug, Clone, Copy)]
147 pub struct SubstitutionHighlight {
152 impl SubstitutionPart {
153 pub fn is_addition(&self, sm: &SourceMap) -> bool {
154 !self.snippet.is_empty()
156 .span_to_snippet(self.span)
157 .map_or(self.span.is_empty(), |snippet| snippet.trim().is_empty())
160 pub fn is_deletion(&self) -> bool {
161 self.snippet.trim().is_empty()
164 pub fn is_replacement(&self, sm: &SourceMap) -> bool {
165 !self.snippet.is_empty()
167 .span_to_snippet(self.span)
168 .map_or(!self.span.is_empty(), |snippet| !snippet.trim().is_empty())
172 impl CodeSuggestion {
173 /// Returns the assembled code suggestions, whether they should be shown with an underline
174 /// and whether the substitution only differs in capitalization.
178 ) -> Vec<(String, Vec<SubstitutionPart>, Vec<Vec<SubstitutionHighlight>>, bool)> {
179 // For the `Vec<Vec<SubstitutionHighlight>>` value, the first level of the vector
180 // corresponds to the output snippet's lines, while the second level corresponds to the
181 // substrings within that line that should be highlighted.
183 use rustc_span::{CharPos, Pos};
185 /// Append to a buffer the remainder of the line of existing source code, and return the
186 /// count of lines that have been added for accurate highlighting.
189 line_opt: Option<&Cow<'_, str>>,
191 hi_opt: Option<&Loc>,
193 let mut line_count = 0;
194 let (lo, hi_opt) = (lo.col.to_usize(), hi_opt.map(|hi| hi.col.to_usize()));
195 if let Some(line) = line_opt {
196 if let Some(lo) = line.char_indices().map(|(i, _)| i).nth(lo) {
197 let hi_opt = hi_opt.and_then(|hi| line.char_indices().map(|(i, _)| i).nth(hi));
199 Some(hi) if hi > lo => {
200 line_count = line[lo..hi].matches('\n').count();
201 buf.push_str(&line[lo..hi])
205 line_count = line[lo..].matches('\n').count();
206 buf.push_str(&line[lo..])
210 if hi_opt.is_none() {
217 assert!(!self.substitutions.is_empty());
222 // Suggestions coming from macros can have malformed spans. This is a heavy
223 // handed approach to avoid ICEs by ignoring the suggestion outright.
224 let invalid = subst.parts.iter().any(|item| sm.is_valid_span(item.span).is_err());
226 debug!("splice_lines: suggestion contains an invalid span: {:?}", subst);
231 .filter_map(|mut substitution| {
232 // Assumption: all spans are in the same file, and all spans
233 // are disjoint. Sort in ascending order.
234 substitution.parts.sort_by_key(|part| part.span.lo());
236 // Find the bounding span.
237 let lo = substitution.parts.iter().map(|part| part.span.lo()).min()?;
238 let hi = substitution.parts.iter().map(|part| part.span.hi()).max()?;
239 let bounding_span = Span::with_root_ctxt(lo, hi);
240 // The different spans might belong to different contexts, if so ignore suggestion.
241 let lines = sm.span_to_lines(bounding_span).ok()?;
242 assert!(!lines.lines.is_empty() || bounding_span.is_dummy());
244 // We can't splice anything if the source is unavailable.
245 if !sm.ensure_source_file_source_present(lines.file.clone()) {
249 let mut highlights = vec![];
250 // To build up the result, we do this for each span:
251 // - push the line segment trailing the previous span
252 // (at the beginning a "phantom" span pointing at the start of the line)
253 // - push lines between the previous and current span (if any)
254 // - if the previous and current span are not on the same line
255 // push the line segment leading up to the current span
256 // - splice in the span substitution
258 // Finally push the trailing line segment of the last span
259 let sf = &lines.file;
260 let mut prev_hi = sm.lookup_char_pos(bounding_span.lo());
261 prev_hi.col = CharPos::from_usize(0);
263 lines.lines.get(0).and_then(|line0| sf.get_line(line0.line_index));
264 let mut buf = String::new();
266 let mut line_highlight = vec![];
267 // We need to keep track of the difference between the existing code and the added
268 // or deleted code in order to point at the correct column *after* substitution.
270 for part in &substitution.parts {
271 let cur_lo = sm.lookup_char_pos(part.span.lo());
272 if prev_hi.line == cur_lo.line {
274 push_trailing(&mut buf, prev_line.as_ref(), &prev_hi, Some(&cur_lo));
276 highlights.push(std::mem::take(&mut line_highlight));
282 highlights.push(std::mem::take(&mut line_highlight));
283 let mut count = push_trailing(&mut buf, prev_line.as_ref(), &prev_hi, None);
285 highlights.push(std::mem::take(&mut line_highlight));
288 // push lines between the previous and current span (if any)
289 for idx in prev_hi.line..(cur_lo.line - 1) {
290 if let Some(line) = sf.get_line(idx) {
291 buf.push_str(line.as_ref());
293 highlights.push(std::mem::take(&mut line_highlight));
296 if let Some(cur_line) = sf.get_line(cur_lo.line - 1) {
297 let end = match cur_line.char_indices().nth(cur_lo.col.to_usize()) {
299 None => cur_line.len(),
301 buf.push_str(&cur_line[..end]);
304 // Add a whole line highlight per line in the snippet.
305 let len: isize = part
309 .unwrap_or(&part.snippet)
316 line_highlight.push(SubstitutionHighlight {
317 start: (cur_lo.col.0 as isize + acc) as usize,
318 end: (cur_lo.col.0 as isize + acc + len) as usize,
320 buf.push_str(&part.snippet);
321 let cur_hi = sm.lookup_char_pos(part.span.hi());
322 if prev_hi.line == cur_lo.line && cur_hi.line == cur_lo.line {
323 // Account for the difference between the width of the current code and the
324 // snippet being suggested, so that the *later* suggestions are correctly
325 // aligned on the screen.
326 acc += len as isize - (cur_hi.col.0 - cur_lo.col.0) as isize;
329 prev_line = sf.get_line(prev_hi.line - 1);
330 for line in part.snippet.split('\n').skip(1) {
332 highlights.push(std::mem::take(&mut line_highlight));
333 let end: usize = line
340 line_highlight.push(SubstitutionHighlight { start: 0, end });
343 highlights.push(std::mem::take(&mut line_highlight));
344 let only_capitalization = is_case_difference(sm, &buf, bounding_span);
345 // if the replacement already ends with a newline, don't print the next line
346 if !buf.ends_with('\n') {
347 push_trailing(&mut buf, prev_line.as_ref(), &prev_hi, None);
349 // remove trailing newlines
350 while buf.ends_with('\n') {
353 Some((buf, substitution.parts, highlights, only_capitalization))
359 pub use rustc_span::fatal_error::{FatalError, FatalErrorMarker};
361 /// Signifies that the compiler died with an explicit call to `.bug`
362 /// or `.span_bug` rather than a failed assertion, etc.
363 #[derive(Copy, Clone, Debug)]
364 pub struct ExplicitBug;
366 impl fmt::Display for ExplicitBug {
367 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
368 write!(f, "parser internal bug")
372 impl error::Error for ExplicitBug {}
374 pub use diagnostic::{
375 AddSubdiagnostic, DecorateLint, Diagnostic, DiagnosticArg, DiagnosticArgFromDisplay,
376 DiagnosticArgValue, DiagnosticId, DiagnosticStyledString, IntoDiagnosticArg, SubDiagnostic,
378 pub use diagnostic_builder::{DiagnosticBuilder, EmissionGuarantee, LintDiagnosticBuilder};
379 use std::backtrace::Backtrace;
381 /// A handler deals with errors and other compiler output.
382 /// Certain errors (fatal, bug, unimpl) may cause immediate exit,
383 /// others log errors for later reporting.
386 inner: Lock<HandlerInner>,
389 /// This inner struct exists to keep it all behind a single lock;
390 /// this is done to prevent possible deadlocks in a multi-threaded compiler,
391 /// as well as inconsistent state observation.
392 struct HandlerInner {
394 /// The number of lint errors that have been emitted.
395 lint_err_count: usize,
396 /// The number of errors that have been emitted, including duplicates.
398 /// This is not necessarily the count that's reported to the user once
399 /// compilation ends.
402 deduplicated_err_count: usize,
403 emitter: Box<dyn Emitter + sync::Send>,
404 delayed_span_bugs: Vec<Diagnostic>,
405 delayed_good_path_bugs: Vec<DelayedDiagnostic>,
406 /// This flag indicates that an expected diagnostic was emitted and suppressed.
407 /// This is used for the `delayed_good_path_bugs` check.
408 suppressed_expected_diag: bool,
410 /// This set contains the `DiagnosticId` of all emitted diagnostics to avoid
411 /// emitting the same diagnostic with extended help (`--teach`) twice, which
412 /// would be unnecessary repetition.
413 taught_diagnostics: FxHashSet<DiagnosticId>,
415 /// Used to suggest rustc --explain <error code>
416 emitted_diagnostic_codes: FxHashSet<DiagnosticId>,
418 /// This set contains a hash of every diagnostic that has been emitted by
419 /// this handler. These hashes is used to avoid emitting the same error
421 emitted_diagnostics: FxHashSet<u128>,
423 /// Stashed diagnostics emitted in one stage of the compiler that may be
424 /// stolen by other stages (e.g. to improve them and add more information).
425 /// The stashed diagnostics count towards the total error count.
426 /// When `.abort_if_errors()` is called, these are also emitted.
427 stashed_diagnostics: FxIndexMap<(Span, StashKey), Diagnostic>,
429 /// The warning count, used for a recap upon finishing
430 deduplicated_warn_count: usize,
432 future_breakage_diagnostics: Vec<Diagnostic>,
434 /// The [`Self::unstable_expect_diagnostics`] should be empty when this struct is
435 /// dropped. However, it can have values if the compilation is stopped early
436 /// or is only partially executed. To avoid ICEs, like in rust#94953 we only
437 /// check if [`Self::unstable_expect_diagnostics`] is empty, if the expectation ids
438 /// have been converted.
439 check_unstable_expect_diagnostics: bool,
441 /// Expected [`Diagnostic`]s store a [`LintExpectationId`] as part of
442 /// the lint level. [`LintExpectationId`]s created early during the compilation
443 /// (before `HirId`s have been defined) are not stable and can therefore not be
444 /// stored on disk. This buffer stores these diagnostics until the ID has been
445 /// replaced by a stable [`LintExpectationId`]. The [`Diagnostic`]s are the
446 /// submitted for storage and added to the list of fulfilled expectations.
447 unstable_expect_diagnostics: Vec<Diagnostic>,
449 /// expected diagnostic will have the level `Expect` which additionally
450 /// carries the [`LintExpectationId`] of the expectation that can be
451 /// marked as fulfilled. This is a collection of all [`LintExpectationId`]s
452 /// that have been marked as fulfilled this way.
454 /// [RFC-2383]: https://rust-lang.github.io/rfcs/2383-lint-reasons.html
455 fulfilled_expectations: FxHashSet<LintExpectationId>,
458 /// A key denoting where from a diagnostic was stashed.
459 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Debug)]
462 UnderscoreForArrayLengths,
466 fn default_track_diagnostic(_: &Diagnostic) {}
468 pub static TRACK_DIAGNOSTICS: AtomicRef<fn(&Diagnostic)> =
469 AtomicRef::new(&(default_track_diagnostic as fn(&_)));
471 #[derive(Copy, Clone, Default)]
472 pub struct HandlerFlags {
473 /// If false, warning-level lints are suppressed.
474 /// (rustc: see `--allow warnings` and `--cap-lints`)
475 pub can_emit_warnings: bool,
476 /// If true, error-level diagnostics are upgraded to bug-level.
477 /// (rustc: see `-Z treat-err-as-bug`)
478 pub treat_err_as_bug: Option<NonZeroUsize>,
479 /// If true, immediately emit diagnostics that would otherwise be buffered.
480 /// (rustc: see `-Z dont-buffer-diagnostics` and `-Z treat-err-as-bug`)
481 pub dont_buffer_diagnostics: bool,
482 /// If true, immediately print bugs registered with `delay_span_bug`.
483 /// (rustc: see `-Z report-delayed-bugs`)
484 pub report_delayed_bugs: bool,
485 /// Show macro backtraces.
486 /// (rustc: see `-Z macro-backtrace`)
487 pub macro_backtrace: bool,
488 /// If true, identical diagnostics are reported only once.
489 pub deduplicate_diagnostics: bool,
492 impl Drop for HandlerInner {
494 self.emit_stashed_diagnostics();
496 if !self.has_errors() {
497 let bugs = std::mem::replace(&mut self.delayed_span_bugs, Vec::new());
498 self.flush_delayed(bugs, "no errors encountered even though `delay_span_bug` issued");
501 // FIXME(eddyb) this explains what `delayed_good_path_bugs` are!
502 // They're `delayed_span_bugs` but for "require some diagnostic happened"
503 // instead of "require some error happened". Sadly that isn't ideal, as
504 // lints can be `#[allow]`'d, potentially leading to this triggering.
505 // Also, "good path" should be replaced with a better naming.
506 if !self.has_any_message() && !self.suppressed_expected_diag {
507 let bugs = std::mem::replace(&mut self.delayed_good_path_bugs, Vec::new());
509 bugs.into_iter().map(DelayedDiagnostic::decorate),
510 "no warnings or errors encountered even though `delayed_good_path_bugs` issued",
514 if self.check_unstable_expect_diagnostics {
516 self.unstable_expect_diagnostics.is_empty(),
517 "all diagnostics with unstable expectations should have been converted",
524 pub fn with_tty_emitter(
525 color_config: ColorConfig,
526 can_emit_warnings: bool,
527 treat_err_as_bug: Option<NonZeroUsize>,
528 sm: Option<Lrc<SourceMap>>,
529 fluent_bundle: Option<Lrc<FluentBundle>>,
530 fallback_bundle: LazyFallbackBundle,
532 Self::with_tty_emitter_and_flags(
537 HandlerFlags { can_emit_warnings, treat_err_as_bug, ..Default::default() },
541 pub fn with_tty_emitter_and_flags(
542 color_config: ColorConfig,
543 sm: Option<Lrc<SourceMap>>,
544 fluent_bundle: Option<Lrc<FluentBundle>>,
545 fallback_bundle: LazyFallbackBundle,
548 let emitter = Box::new(EmitterWriter::stderr(
556 flags.macro_backtrace,
558 Self::with_emitter_and_flags(emitter, flags)
562 can_emit_warnings: bool,
563 treat_err_as_bug: Option<NonZeroUsize>,
564 emitter: Box<dyn Emitter + sync::Send>,
566 Handler::with_emitter_and_flags(
568 HandlerFlags { can_emit_warnings, treat_err_as_bug, ..Default::default() },
572 pub fn with_emitter_and_flags(
573 emitter: Box<dyn Emitter + sync::Send>,
578 inner: Lock::new(HandlerInner {
583 deduplicated_err_count: 0,
584 deduplicated_warn_count: 0,
586 delayed_span_bugs: Vec::new(),
587 delayed_good_path_bugs: Vec::new(),
588 suppressed_expected_diag: false,
589 taught_diagnostics: Default::default(),
590 emitted_diagnostic_codes: Default::default(),
591 emitted_diagnostics: Default::default(),
592 stashed_diagnostics: Default::default(),
593 future_breakage_diagnostics: Vec::new(),
594 check_unstable_expect_diagnostics: false,
595 unstable_expect_diagnostics: Vec::new(),
596 fulfilled_expectations: Default::default(),
601 // This is here to not allow mutation of flags;
602 // as of this writing it's only used in tests in librustc_middle.
603 pub fn can_emit_warnings(&self) -> bool {
604 self.flags.can_emit_warnings
607 /// Resets the diagnostic error count as well as the cached emitted diagnostics.
609 /// NOTE: *do not* call this function from rustc. It is only meant to be called from external
610 /// tools that want to reuse a `Parser` cleaning the previously emitted diagnostics as well as
611 /// the overall count of emitted error diagnostics.
612 pub fn reset_err_count(&self) {
613 let mut inner = self.inner.borrow_mut();
615 inner.warn_count = 0;
616 inner.deduplicated_err_count = 0;
617 inner.deduplicated_warn_count = 0;
619 // actually free the underlying memory (which `clear` would not do)
620 inner.delayed_span_bugs = Default::default();
621 inner.delayed_good_path_bugs = Default::default();
622 inner.taught_diagnostics = Default::default();
623 inner.emitted_diagnostic_codes = Default::default();
624 inner.emitted_diagnostics = Default::default();
625 inner.stashed_diagnostics = Default::default();
628 /// Stash a given diagnostic with the given `Span` and `StashKey` as the key for later stealing.
629 pub fn stash_diagnostic(&self, span: Span, key: StashKey, diag: Diagnostic) {
630 let mut inner = self.inner.borrow_mut();
631 inner.stash((span, key), diag);
634 /// Steal a previously stashed diagnostic with the given `Span` and `StashKey` as the key.
635 pub fn steal_diagnostic(&self, span: Span, key: StashKey) -> Option<DiagnosticBuilder<'_, ()>> {
636 let mut inner = self.inner.borrow_mut();
637 inner.steal((span, key)).map(|diag| DiagnosticBuilder::new_diagnostic(self, diag))
640 /// Emit all stashed diagnostics.
641 pub fn emit_stashed_diagnostics(&self) -> Option<ErrorGuaranteed> {
642 self.inner.borrow_mut().emit_stashed_diagnostics()
645 /// Construct a builder with the `msg` at the level appropriate for the specific `EmissionGuarantee`.
646 #[rustc_lint_diagnostics]
647 pub fn struct_diagnostic<G: EmissionGuarantee>(
649 msg: impl Into<DiagnosticMessage>,
650 ) -> DiagnosticBuilder<'_, G> {
651 G::make_diagnostic_builder(self, msg)
654 /// Construct a builder at the `Warning` level at the given `span` and with the `msg`.
656 /// Attempting to `.emit()` the builder will only emit if either:
657 /// * `can_emit_warnings` is `true`
658 /// * `is_force_warn` was set in `DiagnosticId::Lint`
659 #[rustc_lint_diagnostics]
660 pub fn struct_span_warn(
662 span: impl Into<MultiSpan>,
663 msg: impl Into<DiagnosticMessage>,
664 ) -> DiagnosticBuilder<'_, ()> {
665 let mut result = self.struct_warn(msg);
666 result.set_span(span);
670 /// Construct a builder at the `Warning` level at the given `span` and with the `msg`.
671 /// The `id` is used for lint emissions which should also fulfill a lint expectation.
673 /// Attempting to `.emit()` the builder will only emit if either:
674 /// * `can_emit_warnings` is `true`
675 /// * `is_force_warn` was set in `DiagnosticId::Lint`
676 pub fn struct_span_warn_with_expectation(
678 span: impl Into<MultiSpan>,
679 msg: impl Into<DiagnosticMessage>,
680 id: LintExpectationId,
681 ) -> DiagnosticBuilder<'_, ()> {
682 let mut result = self.struct_warn_with_expectation(msg, id);
683 result.set_span(span);
687 /// Construct a builder at the `Allow` level at the given `span` and with the `msg`.
688 #[rustc_lint_diagnostics]
689 pub fn struct_span_allow(
691 span: impl Into<MultiSpan>,
692 msg: impl Into<DiagnosticMessage>,
693 ) -> DiagnosticBuilder<'_, ()> {
694 let mut result = self.struct_allow(msg);
695 result.set_span(span);
699 /// Construct a builder at the `Warning` level at the given `span` and with the `msg`.
700 /// Also include a code.
701 #[rustc_lint_diagnostics]
702 pub fn struct_span_warn_with_code(
704 span: impl Into<MultiSpan>,
705 msg: impl Into<DiagnosticMessage>,
707 ) -> DiagnosticBuilder<'_, ()> {
708 let mut result = self.struct_span_warn(span, msg);
713 /// Construct a builder at the `Warning` level with the `msg`.
715 /// Attempting to `.emit()` the builder will only emit if either:
716 /// * `can_emit_warnings` is `true`
717 /// * `is_force_warn` was set in `DiagnosticId::Lint`
718 #[rustc_lint_diagnostics]
719 pub fn struct_warn(&self, msg: impl Into<DiagnosticMessage>) -> DiagnosticBuilder<'_, ()> {
720 DiagnosticBuilder::new(self, Level::Warning(None), msg)
723 /// Construct a builder at the `Warning` level with the `msg`. The `id` is used for
724 /// lint emissions which should also fulfill a lint expectation.
726 /// Attempting to `.emit()` the builder will only emit if either:
727 /// * `can_emit_warnings` is `true`
728 /// * `is_force_warn` was set in `DiagnosticId::Lint`
729 pub fn struct_warn_with_expectation(
731 msg: impl Into<DiagnosticMessage>,
732 id: LintExpectationId,
733 ) -> DiagnosticBuilder<'_, ()> {
734 DiagnosticBuilder::new(self, Level::Warning(Some(id)), msg)
737 /// Construct a builder at the `Allow` level with the `msg`.
738 #[rustc_lint_diagnostics]
739 pub fn struct_allow(&self, msg: impl Into<DiagnosticMessage>) -> DiagnosticBuilder<'_, ()> {
740 DiagnosticBuilder::new(self, Level::Allow, msg)
743 /// Construct a builder at the `Expect` level with the `msg`.
744 #[rustc_lint_diagnostics]
745 pub fn struct_expect(
747 msg: impl Into<DiagnosticMessage>,
748 id: LintExpectationId,
749 ) -> DiagnosticBuilder<'_, ()> {
750 DiagnosticBuilder::new(self, Level::Expect(id), msg)
753 /// Construct a builder at the `Error` level at the given `span` and with the `msg`.
754 #[rustc_lint_diagnostics]
755 pub fn struct_span_err(
757 span: impl Into<MultiSpan>,
758 msg: impl Into<DiagnosticMessage>,
759 ) -> DiagnosticBuilder<'_, ErrorGuaranteed> {
760 let mut result = self.struct_err(msg);
761 result.set_span(span);
765 /// Construct a builder at the `Error` level at the given `span`, with the `msg`, and `code`.
766 #[rustc_lint_diagnostics]
767 pub fn struct_span_err_with_code(
769 span: impl Into<MultiSpan>,
770 msg: impl Into<DiagnosticMessage>,
772 ) -> DiagnosticBuilder<'_, ErrorGuaranteed> {
773 let mut result = self.struct_span_err(span, msg);
778 /// Construct a builder at the `Error` level with the `msg`.
779 // FIXME: This method should be removed (every error should have an associated error code).
780 #[rustc_lint_diagnostics]
783 msg: impl Into<DiagnosticMessage>,
784 ) -> DiagnosticBuilder<'_, ErrorGuaranteed> {
785 DiagnosticBuilder::new_guaranteeing_error::<_, { Level::Error { lint: false } }>(self, msg)
788 /// This should only be used by `rustc_middle::lint::struct_lint_level`. Do not use it for hard errors.
790 pub fn struct_err_lint(&self, msg: impl Into<DiagnosticMessage>) -> DiagnosticBuilder<'_, ()> {
791 DiagnosticBuilder::new(self, Level::Error { lint: true }, msg)
794 /// Construct a builder at the `Error` level with the `msg` and the `code`.
795 #[rustc_lint_diagnostics]
796 pub fn struct_err_with_code(
798 msg: impl Into<DiagnosticMessage>,
800 ) -> DiagnosticBuilder<'_, ErrorGuaranteed> {
801 let mut result = self.struct_err(msg);
806 /// Construct a builder at the `Warn` level with the `msg` and the `code`.
807 #[rustc_lint_diagnostics]
808 pub fn struct_warn_with_code(
810 msg: impl Into<DiagnosticMessage>,
812 ) -> DiagnosticBuilder<'_, ()> {
813 let mut result = self.struct_warn(msg);
818 /// Construct a builder at the `Fatal` level at the given `span` and with the `msg`.
819 #[rustc_lint_diagnostics]
820 pub fn struct_span_fatal(
822 span: impl Into<MultiSpan>,
823 msg: impl Into<DiagnosticMessage>,
824 ) -> DiagnosticBuilder<'_, !> {
825 let mut result = self.struct_fatal(msg);
826 result.set_span(span);
830 /// Construct a builder at the `Fatal` level at the given `span`, with the `msg`, and `code`.
831 #[rustc_lint_diagnostics]
832 pub fn struct_span_fatal_with_code(
834 span: impl Into<MultiSpan>,
835 msg: impl Into<DiagnosticMessage>,
837 ) -> DiagnosticBuilder<'_, !> {
838 let mut result = self.struct_span_fatal(span, msg);
843 /// Construct a builder at the `Error` level with the `msg`.
844 #[rustc_lint_diagnostics]
845 pub fn struct_fatal(&self, msg: impl Into<DiagnosticMessage>) -> DiagnosticBuilder<'_, !> {
846 DiagnosticBuilder::new_fatal(self, msg)
849 /// Construct a builder at the `Help` level with the `msg`.
850 #[rustc_lint_diagnostics]
851 pub fn struct_help(&self, msg: impl Into<DiagnosticMessage>) -> DiagnosticBuilder<'_, ()> {
852 DiagnosticBuilder::new(self, Level::Help, msg)
855 /// Construct a builder at the `Note` level with the `msg`.
856 #[rustc_lint_diagnostics]
857 pub fn struct_note_without_error(
859 msg: impl Into<DiagnosticMessage>,
860 ) -> DiagnosticBuilder<'_, ()> {
861 DiagnosticBuilder::new(self, Level::Note, msg)
864 #[rustc_lint_diagnostics]
865 pub fn span_fatal(&self, span: impl Into<MultiSpan>, msg: impl Into<DiagnosticMessage>) -> ! {
866 self.emit_diag_at_span(Diagnostic::new(Fatal, msg), span);
870 #[rustc_lint_diagnostics]
871 pub fn span_fatal_with_code(
873 span: impl Into<MultiSpan>,
874 msg: impl Into<DiagnosticMessage>,
877 self.emit_diag_at_span(Diagnostic::new_with_code(Fatal, Some(code), msg), span);
881 #[rustc_lint_diagnostics]
884 span: impl Into<MultiSpan>,
885 msg: impl Into<DiagnosticMessage>,
886 ) -> ErrorGuaranteed {
887 self.emit_diag_at_span(Diagnostic::new(Error { lint: false }, msg), span).unwrap()
890 #[rustc_lint_diagnostics]
891 pub fn span_err_with_code(
893 span: impl Into<MultiSpan>,
894 msg: impl Into<DiagnosticMessage>,
897 self.emit_diag_at_span(
898 Diagnostic::new_with_code(Error { lint: false }, Some(code), msg),
903 #[rustc_lint_diagnostics]
904 pub fn span_warn(&self, span: impl Into<MultiSpan>, msg: impl Into<DiagnosticMessage>) {
905 self.emit_diag_at_span(Diagnostic::new(Warning(None), msg), span);
908 #[rustc_lint_diagnostics]
909 pub fn span_warn_with_code(
911 span: impl Into<MultiSpan>,
912 msg: impl Into<DiagnosticMessage>,
915 self.emit_diag_at_span(Diagnostic::new_with_code(Warning(None), Some(code), msg), span);
918 pub fn span_bug(&self, span: impl Into<MultiSpan>, msg: impl Into<DiagnosticMessage>) -> ! {
919 self.inner.borrow_mut().span_bug(span, msg)
923 pub fn delay_span_bug(
925 span: impl Into<MultiSpan>,
926 msg: impl Into<DiagnosticMessage>,
927 ) -> ErrorGuaranteed {
928 self.inner.borrow_mut().delay_span_bug(span, msg)
931 // FIXME(eddyb) note the comment inside `impl Drop for HandlerInner`, that's
932 // where the explanation of what "good path" is (also, it should be renamed).
933 pub fn delay_good_path_bug(&self, msg: impl Into<DiagnosticMessage>) {
934 self.inner.borrow_mut().delay_good_path_bug(msg)
937 pub fn span_bug_no_panic(&self, span: impl Into<MultiSpan>, msg: impl Into<DiagnosticMessage>) {
938 self.emit_diag_at_span(Diagnostic::new(Bug, msg), span);
941 pub fn span_note_without_error(
943 span: impl Into<MultiSpan>,
944 msg: impl Into<DiagnosticMessage>,
946 self.emit_diag_at_span(Diagnostic::new(Note, msg), span);
949 pub fn span_note_diag(
952 msg: impl Into<DiagnosticMessage>,
953 ) -> DiagnosticBuilder<'_, ()> {
954 let mut db = DiagnosticBuilder::new(self, Note, msg);
959 // NOTE: intentionally doesn't raise an error so rustc_codegen_ssa only reports fatal errors in the main thread
960 pub fn fatal(&self, msg: impl Into<DiagnosticMessage>) -> FatalError {
961 self.inner.borrow_mut().fatal(msg)
964 pub fn err(&self, msg: impl Into<DiagnosticMessage>) -> ErrorGuaranteed {
965 self.inner.borrow_mut().err(msg)
968 pub fn warn(&self, msg: impl Into<DiagnosticMessage>) {
969 let mut db = DiagnosticBuilder::new(self, Warning(None), msg);
973 pub fn note_without_error(&self, msg: impl Into<DiagnosticMessage>) {
974 DiagnosticBuilder::new(self, Note, msg).emit();
977 pub fn bug(&self, msg: impl Into<DiagnosticMessage>) -> ! {
978 self.inner.borrow_mut().bug(msg)
982 pub fn err_count(&self) -> usize {
983 self.inner.borrow().err_count()
986 pub fn has_errors(&self) -> Option<ErrorGuaranteed> {
987 if self.inner.borrow().has_errors() { Some(ErrorGuaranteed(())) } else { None }
989 pub fn has_errors_or_lint_errors(&self) -> Option<ErrorGuaranteed> {
990 if self.inner.borrow().has_errors_or_lint_errors() {
991 Some(ErrorGuaranteed(()))
996 pub fn has_errors_or_delayed_span_bugs(&self) -> bool {
997 self.inner.borrow().has_errors_or_delayed_span_bugs()
1000 pub fn print_error_count(&self, registry: &Registry) {
1001 self.inner.borrow_mut().print_error_count(registry)
1004 pub fn take_future_breakage_diagnostics(&self) -> Vec<Diagnostic> {
1005 std::mem::take(&mut self.inner.borrow_mut().future_breakage_diagnostics)
1008 pub fn abort_if_errors(&self) {
1009 self.inner.borrow_mut().abort_if_errors()
1012 /// `true` if we haven't taught a diagnostic with this code already.
1013 /// The caller must then teach the user about such a diagnostic.
1015 /// Used to suppress emitting the same error multiple times with extended explanation when
1016 /// calling `-Zteach`.
1017 pub fn must_teach(&self, code: &DiagnosticId) -> bool {
1018 self.inner.borrow_mut().must_teach(code)
1021 pub fn force_print_diagnostic(&self, db: Diagnostic) {
1022 self.inner.borrow_mut().force_print_diagnostic(db)
1025 pub fn emit_diagnostic(&self, diagnostic: &mut Diagnostic) -> Option<ErrorGuaranteed> {
1026 self.inner.borrow_mut().emit_diagnostic(diagnostic)
1029 fn emit_diag_at_span(
1031 mut diag: Diagnostic,
1032 sp: impl Into<MultiSpan>,
1033 ) -> Option<ErrorGuaranteed> {
1034 let mut inner = self.inner.borrow_mut();
1035 inner.emit_diagnostic(diag.set_span(sp))
1038 pub fn emit_artifact_notification(&self, path: &Path, artifact_type: &str) {
1039 self.inner.borrow_mut().emit_artifact_notification(path, artifact_type)
1042 pub fn emit_future_breakage_report(&self, diags: Vec<Diagnostic>) {
1043 self.inner.borrow_mut().emitter.emit_future_breakage_report(diags)
1046 pub fn emit_unused_externs(
1048 lint_level: rustc_lint_defs::Level,
1050 unused_externs: &[&str],
1052 let mut inner = self.inner.borrow_mut();
1054 if loud && lint_level.is_error() {
1055 inner.bump_err_count();
1058 inner.emit_unused_externs(lint_level, unused_externs)
1061 pub fn update_unstable_expectation_id(
1063 unstable_to_stable: &FxHashMap<LintExpectationId, LintExpectationId>,
1065 let mut inner = self.inner.borrow_mut();
1066 let diags = std::mem::take(&mut inner.unstable_expect_diagnostics);
1067 inner.check_unstable_expect_diagnostics = true;
1069 if !diags.is_empty() {
1070 inner.suppressed_expected_diag = true;
1071 for mut diag in diags.into_iter() {
1072 diag.update_unstable_expectation_id(unstable_to_stable);
1074 // Here the diagnostic is given back to `emit_diagnostic` where it was first
1075 // intercepted. Now it should be processed as usual, since the unstable expectation
1076 // id is now stable.
1077 inner.emit_diagnostic(&mut diag);
1082 .stashed_diagnostics
1084 .for_each(|diag| diag.update_unstable_expectation_id(unstable_to_stable));
1086 .future_breakage_diagnostics
1088 .for_each(|diag| diag.update_unstable_expectation_id(unstable_to_stable));
1091 /// This methods steals all [`LintExpectationId`]s that are stored inside
1092 /// [`HandlerInner`] and indicate that the linked expectation has been fulfilled.
1094 pub fn steal_fulfilled_expectation_ids(&self) -> FxHashSet<LintExpectationId> {
1096 self.inner.borrow().unstable_expect_diagnostics.is_empty(),
1097 "`HandlerInner::unstable_expect_diagnostics` should be empty at this point",
1099 std::mem::take(&mut self.inner.borrow_mut().fulfilled_expectations)
1104 fn must_teach(&mut self, code: &DiagnosticId) -> bool {
1105 self.taught_diagnostics.insert(code.clone())
1108 fn force_print_diagnostic(&mut self, mut db: Diagnostic) {
1109 self.emitter.emit_diagnostic(&mut db);
1112 /// Emit all stashed diagnostics.
1113 fn emit_stashed_diagnostics(&mut self) -> Option<ErrorGuaranteed> {
1114 let has_errors = self.has_errors();
1115 let diags = self.stashed_diagnostics.drain(..).map(|x| x.1).collect::<Vec<_>>();
1116 let mut reported = None;
1117 for mut diag in diags {
1118 // Decrement the count tracking the stash; emitting will increment it.
1119 if diag.is_error() {
1120 if matches!(diag.level, Level::Error { lint: true }) {
1121 self.lint_err_count -= 1;
1123 self.err_count -= 1;
1126 if diag.is_force_warn() {
1127 self.warn_count -= 1;
1129 // Unless they're forced, don't flush stashed warnings when
1130 // there are errors, to avoid causing warning overload. The
1131 // stash would've been stolen already if it were important.
1137 let reported_this = self.emit_diagnostic(&mut diag);
1138 reported = reported.or(reported_this);
1143 // FIXME(eddyb) this should ideally take `diagnostic` by value.
1144 fn emit_diagnostic(&mut self, diagnostic: &mut Diagnostic) -> Option<ErrorGuaranteed> {
1145 // The `LintExpectationId` can be stable or unstable depending on when it was created.
1146 // Diagnostics created before the definition of `HirId`s are unstable and can not yet
1147 // be stored. Instead, they are buffered until the `LintExpectationId` is replaced by
1148 // a stable one by the `LintLevelsBuilder`.
1149 if let Some(LintExpectationId::Unstable { .. }) = diagnostic.level.get_expectation_id() {
1150 self.unstable_expect_diagnostics.push(diagnostic.clone());
1154 if diagnostic.level == Level::DelayedBug {
1155 // FIXME(eddyb) this should check for `has_errors` and stop pushing
1156 // once *any* errors were emitted (and truncate `delayed_span_bugs`
1157 // when an error is first emitted, also), but maybe there's a case
1158 // in which that's not sound? otherwise this is really inefficient.
1159 self.delayed_span_bugs.push(diagnostic.clone());
1161 if !self.flags.report_delayed_bugs {
1162 return Some(ErrorGuaranteed::unchecked_claim_error_was_emitted());
1166 if diagnostic.has_future_breakage() {
1167 self.future_breakage_diagnostics.push(diagnostic.clone());
1170 if let Some(expectation_id) = diagnostic.level.get_expectation_id() {
1171 self.suppressed_expected_diag = true;
1172 self.fulfilled_expectations.insert(expectation_id);
1175 if matches!(diagnostic.level, Warning(_))
1176 && !self.flags.can_emit_warnings
1177 && !diagnostic.is_force_warn()
1179 if diagnostic.has_future_breakage() {
1180 (*TRACK_DIAGNOSTICS)(diagnostic);
1185 (*TRACK_DIAGNOSTICS)(diagnostic);
1187 if matches!(diagnostic.level, Level::Expect(_) | Level::Allow) {
1191 if let Some(ref code) = diagnostic.code {
1192 self.emitted_diagnostic_codes.insert(code.clone());
1195 let already_emitted = |this: &mut Self| {
1196 let mut hasher = StableHasher::new();
1197 diagnostic.hash(&mut hasher);
1198 let diagnostic_hash = hasher.finish();
1199 !this.emitted_diagnostics.insert(diagnostic_hash)
1202 // Only emit the diagnostic if we've been asked to deduplicate or
1203 // haven't already emitted an equivalent diagnostic.
1204 if !(self.flags.deduplicate_diagnostics && already_emitted(self)) {
1205 debug!(?diagnostic);
1206 debug!(?self.emitted_diagnostics);
1207 let already_emitted_sub = |sub: &mut SubDiagnostic| {
1209 if sub.level != Level::OnceNote {
1212 let mut hasher = StableHasher::new();
1213 sub.hash(&mut hasher);
1214 let diagnostic_hash = hasher.finish();
1215 debug!(?diagnostic_hash);
1216 !self.emitted_diagnostics.insert(diagnostic_hash)
1219 diagnostic.children.drain_filter(already_emitted_sub).for_each(|_| {});
1221 self.emitter.emit_diagnostic(&diagnostic);
1222 if diagnostic.is_error() {
1223 self.deduplicated_err_count += 1;
1224 } else if let Warning(_) = diagnostic.level {
1225 self.deduplicated_warn_count += 1;
1228 if diagnostic.is_error() {
1229 if matches!(diagnostic.level, Level::Error { lint: true }) {
1230 self.bump_lint_err_count();
1232 self.bump_err_count();
1235 Some(ErrorGuaranteed::unchecked_claim_error_was_emitted())
1237 self.bump_warn_count();
1243 fn emit_artifact_notification(&mut self, path: &Path, artifact_type: &str) {
1244 self.emitter.emit_artifact_notification(path, artifact_type);
1247 fn emit_unused_externs(&mut self, lint_level: rustc_lint_defs::Level, unused_externs: &[&str]) {
1248 self.emitter.emit_unused_externs(lint_level, unused_externs);
1251 fn treat_err_as_bug(&self) -> bool {
1252 self.flags.treat_err_as_bug.map_or(false, |c| {
1254 + self.lint_err_count
1255 + self.delayed_span_bugs.len()
1256 + self.delayed_good_path_bugs.len()
1261 fn print_error_count(&mut self, registry: &Registry) {
1262 self.emit_stashed_diagnostics();
1264 let warnings = match self.deduplicated_warn_count {
1266 1 => "1 warning emitted".to_string(),
1267 count => format!("{count} warnings emitted"),
1269 let errors = match self.deduplicated_err_count {
1271 1 => "aborting due to previous error".to_string(),
1272 count => format!("aborting due to {count} previous errors"),
1274 if self.treat_err_as_bug() {
1278 match (errors.len(), warnings.len()) {
1280 (0, _) => self.emitter.emit_diagnostic(&Diagnostic::new(
1281 Level::Warning(None),
1282 DiagnosticMessage::Str(warnings),
1285 let _ = self.fatal(&errors);
1288 let _ = self.fatal(&format!("{}; {}", &errors, &warnings));
1292 let can_show_explain = self.emitter.should_show_explain();
1293 let are_there_diagnostics = !self.emitted_diagnostic_codes.is_empty();
1294 if can_show_explain && are_there_diagnostics {
1295 let mut error_codes = self
1296 .emitted_diagnostic_codes
1298 .filter_map(|x| match &x {
1299 DiagnosticId::Error(s)
1300 if registry.try_find_description(s).map_or(false, |o| o.is_some()) =>
1306 .collect::<Vec<_>>();
1307 if !error_codes.is_empty() {
1309 if error_codes.len() > 1 {
1310 let limit = if error_codes.len() > 9 { 9 } else { error_codes.len() };
1311 self.failure(&format!(
1312 "Some errors have detailed explanations: {}{}",
1313 error_codes[..limit].join(", "),
1314 if error_codes.len() > 9 { "..." } else { "." }
1316 self.failure(&format!(
1317 "For more information about an error, try \
1318 `rustc --explain {}`.",
1322 self.failure(&format!(
1323 "For more information about this error, try \
1324 `rustc --explain {}`.",
1332 fn stash(&mut self, key: (Span, StashKey), diagnostic: Diagnostic) {
1333 // Track the diagnostic for counts, but don't panic-if-treat-err-as-bug
1334 // yet; that happens when we actually emit the diagnostic.
1335 if diagnostic.is_error() {
1336 if matches!(diagnostic.level, Level::Error { lint: true }) {
1337 self.lint_err_count += 1;
1339 self.err_count += 1;
1342 // Warnings are only automatically flushed if they're forced.
1343 if diagnostic.is_force_warn() {
1344 self.warn_count += 1;
1348 // FIXME(Centril, #69537): Consider reintroducing panic on overwriting a stashed diagnostic
1349 // if/when we have a more robust macro-friendly replacement for `(span, key)` as a key.
1350 // See the PR for a discussion.
1351 self.stashed_diagnostics.insert(key, diagnostic);
1354 fn steal(&mut self, key: (Span, StashKey)) -> Option<Diagnostic> {
1355 let diagnostic = self.stashed_diagnostics.remove(&key)?;
1356 if diagnostic.is_error() {
1357 if matches!(diagnostic.level, Level::Error { lint: true }) {
1358 self.lint_err_count -= 1;
1360 self.err_count -= 1;
1363 if diagnostic.is_force_warn() {
1364 self.warn_count -= 1;
1371 fn err_count(&self) -> usize {
1375 fn has_errors(&self) -> bool {
1376 self.err_count() > 0
1378 fn has_errors_or_lint_errors(&self) -> bool {
1379 self.has_errors() || self.lint_err_count > 0
1381 fn has_errors_or_delayed_span_bugs(&self) -> bool {
1382 self.has_errors() || !self.delayed_span_bugs.is_empty()
1384 fn has_any_message(&self) -> bool {
1385 self.err_count() > 0 || self.lint_err_count > 0 || self.warn_count > 0
1388 fn abort_if_errors(&mut self) {
1389 self.emit_stashed_diagnostics();
1391 if self.has_errors() {
1396 fn span_bug(&mut self, sp: impl Into<MultiSpan>, msg: impl Into<DiagnosticMessage>) -> ! {
1397 self.emit_diag_at_span(Diagnostic::new(Bug, msg), sp);
1398 panic::panic_any(ExplicitBug);
1401 fn emit_diag_at_span(&mut self, mut diag: Diagnostic, sp: impl Into<MultiSpan>) {
1402 self.emit_diagnostic(diag.set_span(sp));
1408 sp: impl Into<MultiSpan>,
1409 msg: impl Into<DiagnosticMessage>,
1410 ) -> ErrorGuaranteed {
1411 // This is technically `self.treat_err_as_bug()` but `delay_span_bug` is called before
1412 // incrementing `err_count` by one, so we need to +1 the comparing.
1413 // FIXME: Would be nice to increment err_count in a more coherent way.
1414 if self.flags.treat_err_as_bug.map_or(false, |c| {
1416 + self.lint_err_count
1417 + self.delayed_span_bugs.len()
1418 + self.delayed_good_path_bugs.len()
1422 // FIXME: don't abort here if report_delayed_bugs is off
1423 self.span_bug(sp, msg);
1425 let mut diagnostic = Diagnostic::new(Level::DelayedBug, msg);
1426 diagnostic.set_span(sp.into());
1427 diagnostic.note(&format!("delayed at {}", std::panic::Location::caller()));
1428 self.emit_diagnostic(&mut diagnostic).unwrap()
1431 // FIXME(eddyb) note the comment inside `impl Drop for HandlerInner`, that's
1432 // where the explanation of what "good path" is (also, it should be renamed).
1433 fn delay_good_path_bug(&mut self, msg: impl Into<DiagnosticMessage>) {
1434 let mut diagnostic = Diagnostic::new(Level::DelayedBug, msg);
1435 if self.flags.report_delayed_bugs {
1436 self.emit_diagnostic(&mut diagnostic);
1438 let backtrace = std::backtrace::Backtrace::force_capture();
1439 self.delayed_good_path_bugs.push(DelayedDiagnostic::with_backtrace(diagnostic, backtrace));
1442 fn failure(&mut self, msg: impl Into<DiagnosticMessage>) {
1443 self.emit_diagnostic(&mut Diagnostic::new(FailureNote, msg));
1446 fn fatal(&mut self, msg: impl Into<DiagnosticMessage>) -> FatalError {
1447 self.emit(Fatal, msg);
1451 fn err(&mut self, msg: impl Into<DiagnosticMessage>) -> ErrorGuaranteed {
1452 self.emit(Error { lint: false }, msg)
1455 /// Emit an error; level should be `Error` or `Fatal`.
1456 fn emit(&mut self, level: Level, msg: impl Into<DiagnosticMessage>) -> ErrorGuaranteed {
1457 if self.treat_err_as_bug() {
1460 self.emit_diagnostic(&mut Diagnostic::new(level, msg)).unwrap()
1463 fn bug(&mut self, msg: impl Into<DiagnosticMessage>) -> ! {
1464 self.emit_diagnostic(&mut Diagnostic::new(Bug, msg));
1465 panic::panic_any(ExplicitBug);
1470 bugs: impl IntoIterator<Item = Diagnostic>,
1471 explanation: impl Into<DiagnosticMessage> + Copy,
1473 let mut no_bugs = true;
1474 for mut bug in bugs {
1476 // Put the overall explanation before the `DelayedBug`s, to
1477 // frame them better (e.g. separate warnings from them).
1478 self.emit_diagnostic(&mut Diagnostic::new(Bug, explanation));
1482 // "Undelay" the `DelayedBug`s (into plain `Bug`s).
1483 if bug.level != Level::DelayedBug {
1484 // NOTE(eddyb) not panicking here because we're already producing
1485 // an ICE, and the more information the merrier.
1487 "`flushed_delayed` got diagnostic with level {:?}, \
1488 instead of the expected `DelayedBug`",
1492 bug.level = Level::Bug;
1494 self.emit_diagnostic(&mut bug);
1497 // Panic with `ExplicitBug` to avoid "unexpected panic" messages.
1499 panic::panic_any(ExplicitBug);
1503 fn bump_lint_err_count(&mut self) {
1504 self.lint_err_count += 1;
1505 self.panic_if_treat_err_as_bug();
1508 fn bump_err_count(&mut self) {
1509 self.err_count += 1;
1510 self.panic_if_treat_err_as_bug();
1513 fn bump_warn_count(&mut self) {
1514 self.warn_count += 1;
1517 fn panic_if_treat_err_as_bug(&self) {
1518 if self.treat_err_as_bug() {
1520 self.err_count() + self.lint_err_count,
1521 self.flags.treat_err_as_bug.map(|c| c.get()).unwrap_or(0),
1523 (1, 1) => panic!("aborting due to `-Z treat-err-as-bug=1`"),
1525 (count, as_bug) => panic!(
1526 "aborting after {} errors due to `-Z treat-err-as-bug={}`",
1534 struct DelayedDiagnostic {
1539 impl DelayedDiagnostic {
1540 fn with_backtrace(diagnostic: Diagnostic, backtrace: Backtrace) -> Self {
1541 DelayedDiagnostic { inner: diagnostic, note: backtrace }
1544 fn decorate(mut self) -> Diagnostic {
1545 self.inner.note(&format!("delayed at {}", self.note));
1550 #[derive(Copy, PartialEq, Eq, Clone, Hash, Debug, Encodable, Decodable)]
1556 /// If this error comes from a lint, don't abort compilation even when abort_if_errors() is called.
1559 /// This [`LintExpectationId`] is used for expected lint diagnostics, which should
1560 /// also emit a warning due to the `force-warn` flag. In all other cases this should
1562 Warning(Option<LintExpectationId>),
1564 /// A note that is only emitted once.
1569 Expect(LintExpectationId),
1572 impl fmt::Display for Level {
1573 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1574 self.to_str().fmt(f)
1579 fn color(self) -> ColorSpec {
1580 let mut spec = ColorSpec::new();
1582 Bug | DelayedBug | Fatal | Error { .. } => {
1583 spec.set_fg(Some(Color::Red)).set_intense(true);
1586 spec.set_fg(Some(Color::Yellow)).set_intense(cfg!(windows));
1588 Note | OnceNote => {
1589 spec.set_fg(Some(Color::Green)).set_intense(true);
1592 spec.set_fg(Some(Color::Cyan)).set_intense(true);
1595 Allow | Expect(_) => unreachable!(),
1600 pub fn to_str(self) -> &'static str {
1602 Bug | DelayedBug => "error: internal compiler error",
1603 Fatal | Error { .. } => "error",
1604 Warning(_) => "warning",
1605 Note | OnceNote => "note",
1607 FailureNote => "failure-note",
1608 Allow => panic!("Shouldn't call on allowed error"),
1609 Expect(_) => panic!("Shouldn't call on expected error"),
1613 pub fn is_failure_note(&self) -> bool {
1614 matches!(*self, FailureNote)
1617 pub fn get_expectation_id(&self) -> Option<LintExpectationId> {
1619 Level::Expect(id) | Level::Warning(Some(id)) => Some(*id),
1625 // FIXME(eddyb) this doesn't belong here AFAICT, should be moved to callsite.
1626 pub fn add_elided_lifetime_in_path_suggestion(
1627 source_map: &SourceMap,
1628 diag: &mut Diagnostic,
1631 incl_angl_brckt: bool,
1632 insertion_span: Span,
1634 diag.span_label(path_span, format!("expected lifetime parameter{}", pluralize!(n)));
1635 if !source_map.is_span_accessible(insertion_span) {
1636 // Do not try to suggest anything if generated by a proc-macro.
1639 let anon_lts = vec!["'_"; n].join(", ");
1641 if incl_angl_brckt { format!("<{}>", anon_lts) } else { format!("{}, ", anon_lts) };
1642 diag.span_suggestion_verbose(
1643 insertion_span.shrink_to_hi(),
1644 &format!("indicate the anonymous lifetime{}", pluralize!(n)),
1646 Applicability::MachineApplicable,
1650 /// Useful type to use with `Result<>` indicate that an error has already
1651 /// been reported to the user, so no need to continue checking.
1652 #[derive(Clone, Copy, Debug, Encodable, Decodable, Hash, PartialEq, Eq, PartialOrd, Ord)]
1653 #[derive(HashStable_Generic)]
1654 pub struct ErrorGuaranteed(());
1656 impl ErrorGuaranteed {
1657 /// To be used only if you really know what you are doing... ideally, we would find a way to
1658 /// eliminate all calls to this method.
1659 pub fn unchecked_claim_error_was_emitted() -> Self {