diff options
Diffstat (limited to 'compiler/rustc_errors/src/lib.rs')
| -rw-r--r-- | compiler/rustc_errors/src/lib.rs | 211 |
1 files changed, 149 insertions, 62 deletions
diff --git a/compiler/rustc_errors/src/lib.rs b/compiler/rustc_errors/src/lib.rs index bc338b01d8b..60bda9f4c94 100644 --- a/compiler/rustc_errors/src/lib.rs +++ b/compiler/rustc_errors/src/lib.rs @@ -434,10 +434,6 @@ struct DiagCtxtInner { /// The delayed bugs and their error guarantees. delayed_bugs: Vec<(DelayedDiagInner, ErrorGuaranteed)>, - /// The number of stashed errors. Unlike the other counts, this can go up - /// and down, so it doesn't guarantee anything. - stashed_err_count: usize, - /// The error count shown to the user at the end. deduplicated_err_count: usize, /// The warning count shown to the user at the end. @@ -475,7 +471,7 @@ struct DiagCtxtInner { /// add more information). All stashed diagnostics must be emitted with /// `emit_stashed_diagnostics` by the time the `DiagCtxtInner` is dropped, /// otherwise an assertion failure will occur. - stashed_diagnostics: FxIndexMap<(Span, StashKey), DiagInner>, + stashed_diagnostics: FxIndexMap<(Span, StashKey), (DiagInner, Option<ErrorGuaranteed>)>, future_breakage_diagnostics: Vec<DiagInner>, @@ -561,8 +557,14 @@ impl Drop for DiagCtxtInner { fn drop(&mut self) { // Any stashed diagnostics should have been handled by // `emit_stashed_diagnostics` by now. + // + // Important: it is sound to produce an `ErrorGuaranteed` when stashing + // errors because they are guaranteed to have been emitted by here. assert!(self.stashed_diagnostics.is_empty()); + // Important: it is sound to produce an `ErrorGuaranteed` when emitting + // delayed bugs because they are guaranteed to be emitted here if + // necessary. if self.err_guars.is_empty() { self.flush_delayed() } @@ -615,7 +617,6 @@ impl DiagCtxt { err_guars: Vec::new(), lint_err_guars: Vec::new(), delayed_bugs: Vec::new(), - stashed_err_count: 0, deduplicated_err_count: 0, deduplicated_warn_count: 0, emitter, @@ -676,7 +677,6 @@ impl DiagCtxt { err_guars, lint_err_guars, delayed_bugs, - stashed_err_count, deduplicated_err_count, deduplicated_warn_count, emitter: _, @@ -699,7 +699,6 @@ impl DiagCtxt { *err_guars = Default::default(); *lint_err_guars = Default::default(); *delayed_bugs = Default::default(); - *stashed_err_count = 0; *deduplicated_err_count = 0; *deduplicated_warn_count = 0; *must_produce_diag = false; @@ -715,39 +714,111 @@ impl DiagCtxt { *fulfilled_expectations = Default::default(); } - /// Stash a given diagnostic with the given `Span` and [`StashKey`] as the key. - /// Retrieve a stashed diagnostic with `steal_diagnostic`. - pub fn stash_diagnostic(&self, span: Span, key: StashKey, diag: DiagInner) { - let mut inner = self.inner.borrow_mut(); - - let key = (span.with_parent(None), key); - - if diag.is_error() { - if diag.is_lint.is_none() { - inner.stashed_err_count += 1; - } - } + /// Stashes a diagnostic for possible later improvement in a different, + /// later stage of the compiler. Possible actions depend on the diagnostic + /// level: + /// - Level::Error: immediately counted as an error that has occurred, because it + /// is guaranteed to be emitted eventually. Can be later accessed with the + /// provided `span` and `key` through + /// [`DiagCtxt::try_steal_modify_and_emit_err`] or + /// [`DiagCtxt::try_steal_replace_and_emit_err`]. These do not allow + /// cancellation or downgrading of the error. Returns + /// `Some(ErrorGuaranteed)`. + /// - Level::Warning and lower (i.e. !is_error()): can be accessed with the + /// provided `span` and `key` through [`DiagCtxt::steal_non_err()`]. This + /// allows cancelling and downgrading of the diagnostic. Returns `None`. + /// - Others: not allowed, will trigger a panic. + pub fn stash_diagnostic( + &self, + span: Span, + key: StashKey, + diag: DiagInner, + ) -> Option<ErrorGuaranteed> { + let guar = if diag.level() == Level::Error { + // This `unchecked_error_guaranteed` is valid. It is where the + // `ErrorGuaranteed` for stashed errors originates. See + // `DiagCtxtInner::drop`. + #[allow(deprecated)] + Some(ErrorGuaranteed::unchecked_error_guaranteed()) + } else if !diag.is_error() { + None + } else { + self.span_bug(span, format!("invalid level in `stash_diagnostic`: {}", diag.level)); + }; // FIXME(Centril, #69537): Consider reintroducing panic on overwriting a stashed diagnostic // if/when we have a more robust macro-friendly replacement for `(span, key)` as a key. // See the PR for a discussion. - inner.stashed_diagnostics.insert(key, diag); + let key = (span.with_parent(None), key); + self.inner.borrow_mut().stashed_diagnostics.insert(key, (diag, guar)); + + guar } - /// Steal a previously stashed diagnostic with the given `Span` and [`StashKey`] as the key. - pub fn steal_diagnostic(&self, span: Span, key: StashKey) -> Option<Diag<'_, ()>> { - let mut inner = self.inner.borrow_mut(); + /// Steal a previously stashed non-error diagnostic with the given `Span` + /// and [`StashKey`] as the key. Panics if the found diagnostic is an + /// error. + pub fn steal_non_err(&self, span: Span, key: StashKey) -> Option<Diag<'_, ()>> { let key = (span.with_parent(None), key); // FIXME(#120456) - is `swap_remove` correct? - let diag = inner.stashed_diagnostics.swap_remove(&key)?; - if diag.is_error() { - if diag.is_lint.is_none() { - inner.stashed_err_count -= 1; - } - } + let (diag, guar) = self.inner.borrow_mut().stashed_diagnostics.swap_remove(&key)?; + assert!(!diag.is_error()); + assert!(guar.is_none()); Some(Diag::new_diagnostic(self, diag)) } + /// Steals a previously stashed error with the given `Span` and + /// [`StashKey`] as the key, modifies it, and emits it. Returns `None` if + /// no matching diagnostic is found. Panics if the found diagnostic's level + /// isn't `Level::Error`. + pub fn try_steal_modify_and_emit_err<F>( + &self, + span: Span, + key: StashKey, + mut modify_err: F, + ) -> Option<ErrorGuaranteed> + where + F: FnMut(&mut Diag<'_>), + { + let key = (span.with_parent(None), key); + // FIXME(#120456) - is `swap_remove` correct? + let err = self.inner.borrow_mut().stashed_diagnostics.swap_remove(&key); + err.map(|(err, guar)| { + // The use of `::<ErrorGuaranteed>` is safe because level is `Level::Error`. + assert_eq!(err.level, Level::Error); + assert!(guar.is_some()); + let mut err = Diag::<ErrorGuaranteed>::new_diagnostic(self, err); + modify_err(&mut err); + assert_eq!(err.level, Level::Error); + err.emit() + }) + } + + /// Steals a previously stashed error with the given `Span` and + /// [`StashKey`] as the key, cancels it if found, and emits `new_err`. + /// Panics if the found diagnostic's level isn't `Level::Error`. + pub fn try_steal_replace_and_emit_err( + &self, + span: Span, + key: StashKey, + new_err: Diag<'_>, + ) -> ErrorGuaranteed { + let key = (span.with_parent(None), key); + // FIXME(#120456) - is `swap_remove` correct? + let old_err = self.inner.borrow_mut().stashed_diagnostics.swap_remove(&key); + match old_err { + Some((old_err, guar)) => { + assert_eq!(old_err.level, Level::Error); + assert!(guar.is_some()); + // Because `old_err` has already been counted, it can only be + // safely cancelled because the `new_err` supplants it. + Diag::<ErrorGuaranteed>::new_diagnostic(self, old_err).cancel(); + } + None => {} + }; + new_err.emit() + } + pub fn has_stashed_diagnostic(&self, span: Span, key: StashKey) -> bool { self.inner.borrow().stashed_diagnostics.get(&(span.with_parent(None), key)).is_some() } @@ -757,41 +828,40 @@ impl DiagCtxt { self.inner.borrow_mut().emit_stashed_diagnostics() } - /// This excludes lint errors, delayed bugs and stashed errors. + /// This excludes lint errors, and delayed bugs. #[inline] pub fn err_count_excluding_lint_errs(&self) -> usize { - self.inner.borrow().err_guars.len() + let inner = self.inner.borrow(); + inner.err_guars.len() + + inner + .stashed_diagnostics + .values() + .filter(|(diag, guar)| guar.is_some() && diag.is_lint.is_none()) + .count() } - /// This excludes delayed bugs and stashed errors. + /// This excludes delayed bugs. #[inline] pub fn err_count(&self) -> usize { let inner = self.inner.borrow(); - inner.err_guars.len() + inner.lint_err_guars.len() + inner.err_guars.len() + + inner.lint_err_guars.len() + + inner.stashed_diagnostics.values().filter(|(_diag, guar)| guar.is_some()).count() } - /// This excludes normal errors, lint errors, and delayed bugs. Unless - /// absolutely necessary, avoid using this. It's dubious because stashed - /// errors can later be cancelled, so the presence of a stashed error at - /// some point of time doesn't guarantee anything -- there are no - /// `ErrorGuaranteed`s here. - pub fn stashed_err_count(&self) -> usize { - self.inner.borrow().stashed_err_count - } - - /// This excludes lint errors, delayed bugs, and stashed errors. Unless - /// absolutely necessary, prefer `has_errors` to this method. + /// This excludes lint errors and delayed bugs. Unless absolutely + /// necessary, prefer `has_errors` to this method. pub fn has_errors_excluding_lint_errors(&self) -> Option<ErrorGuaranteed> { self.inner.borrow().has_errors_excluding_lint_errors() } - /// This excludes delayed bugs and stashed errors. + /// This excludes delayed bugs. pub fn has_errors(&self) -> Option<ErrorGuaranteed> { self.inner.borrow().has_errors() } - /// This excludes stashed errors. Unless absolutely necessary, prefer - /// `has_errors` to this method. + /// This excludes nothing. Unless absolutely necessary, prefer `has_errors` + /// to this method. pub fn has_errors_or_delayed_bugs(&self) -> Option<ErrorGuaranteed> { self.inner.borrow().has_errors_or_delayed_bugs() } @@ -876,10 +946,10 @@ impl DiagCtxt { } } - /// This excludes delayed bugs and stashed errors. Used for early aborts - /// after errors occurred -- e.g. because continuing in the face of errors is - /// likely to lead to bad results, such as spurious/uninteresting - /// additional errors -- when returning an error `Result` is difficult. + /// This excludes delayed bugs. Used for early aborts after errors occurred + /// -- e.g. because continuing in the face of errors is likely to lead to + /// bad results, such as spurious/uninteresting additional errors -- when + /// returning an error `Result` is difficult. pub fn abort_if_errors(&self) { if self.has_errors().is_some() { FatalError.raise(); @@ -963,7 +1033,7 @@ impl DiagCtxt { inner .stashed_diagnostics .values_mut() - .for_each(|diag| diag.update_unstable_expectation_id(unstable_to_stable)); + .for_each(|(diag, _guar)| diag.update_unstable_expectation_id(unstable_to_stable)); inner .future_breakage_diagnostics .iter_mut() @@ -1270,12 +1340,8 @@ impl DiagCtxtInner { fn emit_stashed_diagnostics(&mut self) -> Option<ErrorGuaranteed> { let mut guar = None; let has_errors = !self.err_guars.is_empty(); - for (_, diag) in std::mem::take(&mut self.stashed_diagnostics).into_iter() { - if diag.is_error() { - if diag.is_lint.is_none() { - self.stashed_err_count -= 1; - } - } else { + for (_, (diag, _guar)) in std::mem::take(&mut self.stashed_diagnostics).into_iter() { + if !diag.is_error() { // Unless they're forced, don't flush stashed warnings when // there are errors, to avoid causing warning overload. The // stash would've been stolen already if it were important. @@ -1334,7 +1400,8 @@ impl DiagCtxtInner { } else { let backtrace = std::backtrace::Backtrace::capture(); // This `unchecked_error_guaranteed` is valid. It is where the - // `ErrorGuaranteed` for delayed bugs originates. + // `ErrorGuaranteed` for delayed bugs originates. See + // `DiagCtxtInner::drop`. #[allow(deprecated)] let guar = ErrorGuaranteed::unchecked_error_guaranteed(); self.delayed_bugs @@ -1446,11 +1513,31 @@ impl DiagCtxtInner { } fn has_errors_excluding_lint_errors(&self) -> Option<ErrorGuaranteed> { - self.err_guars.get(0).copied() + self.err_guars.get(0).copied().or_else(|| { + if let Some((_diag, guar)) = self + .stashed_diagnostics + .values() + .find(|(diag, guar)| guar.is_some() && diag.is_lint.is_none()) + { + *guar + } else { + None + } + }) } fn has_errors(&self) -> Option<ErrorGuaranteed> { - self.has_errors_excluding_lint_errors().or_else(|| self.lint_err_guars.get(0).copied()) + self.err_guars.get(0).copied().or_else(|| self.lint_err_guars.get(0).copied()).or_else( + || { + if let Some((_diag, guar)) = + self.stashed_diagnostics.values().find(|(_diag, guar)| guar.is_some()) + { + *guar + } else { + None + } + }, + ) } fn has_errors_or_delayed_bugs(&self) -> Option<ErrorGuaranteed> { |