Split Level::DelayedBug in two.

The two kinds of delayed bug have quite different semantics so a
stronger conceptual separation is nice. (`is_error` is a good example,
because the two kinds have different behaviour.)

The commit also moves the `DelayedBug` variant after `Error` in `Level`,
to reflect the fact that it's weaker than `Error` -- it might trigger an
error but also might not. (The pre-existing `downgrade_to_delayed_bug`
function also reflects the notion that delayed bugs are lower/after
normal errors.)

Plus it condenses some of the comments on `Level` into a table, for
easier reading, and introduces `can_be_top_or_sub` to indicate which
levels can be used in top-level diagnostics vs. subdiagnostics.

Finally, it renames `DiagCtxtInner::span_delayed_bugs` as
`DiagCtxtInner::delayed_bugs`. The `span_` prefix is unnecessary because
some delayed bugs don't have a span.
This commit is contained in:
Nicholas Nethercote 2024-01-31 11:23:54 +11:00
parent c367386832
commit 59e0bc2de7
7 changed files with 102 additions and 90 deletions

View File

@ -378,7 +378,7 @@ impl From<Cow<'static, str>> for DiagnosticMessage {
}
}
/// A workaround for "good path" ICEs when formatting types in disabled lints.
/// A workaround for good_path_delayed_bug ICEs when formatting types in disabled lints.
///
/// Delays formatting until `.into(): DiagnosticMessage` is used.
pub struct DelayDm<F>(pub F);

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@ -85,7 +85,11 @@ fn source_string(file: Lrc<SourceFile>, line: &Line) -> String {
/// Maps `Diagnostic::Level` to `snippet::AnnotationType`
fn annotation_type_for_level(level: Level) -> AnnotationType {
match level {
Level::Bug | Level::DelayedBug(_) | Level::Fatal | Level::Error => AnnotationType::Error,
Level::Bug
| Level::Fatal
| Level::Error
| Level::DelayedBug
| Level::GoodPathDelayedBug => AnnotationType::Error,
Level::ForceWarning(_) | Level::Warning => AnnotationType::Warning,
Level::Note | Level::OnceNote => AnnotationType::Note,
Level::Help | Level::OnceHelp => AnnotationType::Help,

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@ -1,8 +1,7 @@
use crate::snippet::Style;
use crate::{
CodeSuggestion, DelayedBugKind, DiagnosticBuilder, DiagnosticMessage, EmissionGuarantee,
ErrCode, Level, MultiSpan, SubdiagnosticMessage, Substitution, SubstitutionPart,
SuggestionStyle,
CodeSuggestion, DiagnosticBuilder, DiagnosticMessage, EmissionGuarantee, ErrCode, Level,
MultiSpan, SubdiagnosticMessage, Substitution, SubstitutionPart, SuggestionStyle,
};
use rustc_data_structures::fx::{FxHashMap, FxIndexMap};
use rustc_error_messages::fluent_value_from_str_list_sep_by_and;
@ -235,14 +234,11 @@ impl Diagnostic {
pub fn is_error(&self) -> bool {
match self.level {
Level::Bug
| Level::DelayedBug(DelayedBugKind::Normal)
| Level::Fatal
| Level::Error => true,
Level::Bug | Level::Fatal | Level::Error | Level::DelayedBug => true,
Level::ForceWarning(_)
Level::GoodPathDelayedBug
| Level::ForceWarning(_)
| Level::Warning
| Level::DelayedBug(DelayedBugKind::GoodPath)
| Level::Note
| Level::OnceNote
| Level::Help
@ -306,11 +302,11 @@ impl Diagnostic {
#[track_caller]
pub fn downgrade_to_delayed_bug(&mut self) {
assert!(
matches!(self.level, Level::Error | Level::DelayedBug(_)),
matches!(self.level, Level::Error | Level::DelayedBug),
"downgrade_to_delayed_bug: cannot downgrade {:?} to DelayedBug: not an error",
self.level
);
self.level = Level::DelayedBug(DelayedBugKind::Normal);
self.level = Level::DelayedBug;
}
/// Appends a labeled span to the diagnostic.

View File

@ -2116,6 +2116,7 @@ impl HumanEmitter {
}
if !self.short_message {
for child in children {
assert!(child.level.can_be_top_or_sub().1);
let span = &child.span;
if let Err(err) = self.emit_messages_default_inner(
span,

View File

@ -439,7 +439,7 @@ struct DiagCtxtInner {
has_printed: bool,
emitter: Box<DynEmitter>,
span_delayed_bugs: Vec<DelayedDiagnostic>,
delayed_bugs: Vec<DelayedDiagnostic>,
good_path_delayed_bugs: Vec<DelayedDiagnostic>,
/// This flag indicates that an expected diagnostic was emitted and suppressed.
/// This is used for the `good_path_delayed_bugs` check.
@ -523,8 +523,7 @@ fn default_track_diagnostic(diag: Diagnostic, f: &mut dyn FnMut(Diagnostic)) {
pub static TRACK_DIAGNOSTIC: AtomicRef<fn(Diagnostic, &mut dyn FnMut(Diagnostic))> =
AtomicRef::new(&(default_track_diagnostic as _));
#[derive(Copy, PartialEq, Eq, Clone, Hash, Debug, Encodable, Decodable)]
pub enum DelayedBugKind {
enum DelayedBugKind {
Normal,
GoodPath,
}
@ -557,11 +556,6 @@ impl Drop for DiagCtxtInner {
self.flush_delayed(DelayedBugKind::Normal)
}
// FIXME(eddyb) this explains what `good_path_delayed_bugs` are!
// They're `span_delayed_bugs` but for "require some diagnostic happened"
// instead of "require some error happened". Sadly that isn't ideal, as
// lints can be `#[allow]`'d, potentially leading to this triggering.
// Also, "good path" should be replaced with a better naming.
if !self.has_printed && !self.suppressed_expected_diag && !std::thread::panicking() {
self.flush_delayed(DelayedBugKind::GoodPath);
}
@ -608,7 +602,7 @@ impl DiagCtxt {
deduplicated_warn_count: 0,
has_printed: false,
emitter,
span_delayed_bugs: Vec::new(),
delayed_bugs: Vec::new(),
good_path_delayed_bugs: Vec::new(),
suppressed_expected_diag: false,
taught_diagnostics: Default::default(),
@ -664,7 +658,7 @@ impl DiagCtxt {
inner.has_printed = false;
// actually free the underlying memory (which `clear` would not do)
inner.span_delayed_bugs = Default::default();
inner.delayed_bugs = Default::default();
inner.good_path_delayed_bugs = Default::default();
inner.taught_diagnostics = Default::default();
inner.emitted_diagnostic_codes = Default::default();
@ -865,8 +859,7 @@ impl DiagCtxt {
/// directly).
#[track_caller]
pub fn delayed_bug(&self, msg: impl Into<DiagnosticMessage>) -> ErrorGuaranteed {
DiagnosticBuilder::<ErrorGuaranteed>::new(self, DelayedBug(DelayedBugKind::Normal), msg)
.emit()
DiagnosticBuilder::<ErrorGuaranteed>::new(self, DelayedBug, msg).emit()
}
/// Like `delayed_bug`, but takes an additional span.
@ -879,15 +872,12 @@ impl DiagCtxt {
sp: impl Into<MultiSpan>,
msg: impl Into<DiagnosticMessage>,
) -> ErrorGuaranteed {
DiagnosticBuilder::<ErrorGuaranteed>::new(self, DelayedBug(DelayedBugKind::Normal), msg)
.with_span(sp)
.emit()
DiagnosticBuilder::<ErrorGuaranteed>::new(self, DelayedBug, msg).with_span(sp).emit()
}
// FIXME(eddyb) note the comment inside `impl Drop for DiagCtxtInner`, that's
// where the explanation of what "good path" is (also, it should be renamed).
/// Ensures that a diagnostic is printed. See `Level::GoodPathDelayedBug`.
pub fn good_path_delayed_bug(&self, msg: impl Into<DiagnosticMessage>) {
DiagnosticBuilder::<()>::new(self, DelayedBug(DelayedBugKind::GoodPath), msg).emit()
DiagnosticBuilder::<()>::new(self, GoodPathDelayedBug, msg).emit()
}
#[track_caller]
@ -961,7 +951,7 @@ impl DiagCtxt {
pub fn has_errors_or_lint_errors_or_delayed_bugs(&self) -> Option<ErrorGuaranteed> {
let inner = self.inner.borrow();
let result =
inner.has_errors() || inner.lint_err_count > 0 || !inner.span_delayed_bugs.is_empty();
inner.has_errors() || inner.lint_err_count > 0 || !inner.delayed_bugs.is_empty();
result.then(|| {
#[allow(deprecated)]
ErrorGuaranteed::unchecked_claim_error_was_emitted()
@ -1247,6 +1237,8 @@ impl DiagCtxtInner {
}
fn emit_diagnostic(&mut self, mut diagnostic: Diagnostic) -> Option<ErrorGuaranteed> {
assert!(diagnostic.level.can_be_top_or_sub().0);
if let Some(expectation_id) = diagnostic.level.get_expectation_id() {
// The `LintExpectationId` can be stable or unstable depending on when it was created.
// Diagnostics created before the definition of `HirId`s are unstable and can not yet
@ -1268,27 +1260,29 @@ impl DiagCtxtInner {
self.future_breakage_diagnostics.push(diagnostic.clone());
}
if matches!(diagnostic.level, DelayedBug(_)) && self.flags.eagerly_emit_delayed_bugs {
if matches!(diagnostic.level, DelayedBug | GoodPathDelayedBug)
&& self.flags.eagerly_emit_delayed_bugs
{
diagnostic.level = Error;
}
match diagnostic.level {
// This must come after the possible promotion of `DelayedBug` to `Error` above.
// This must come after the possible promotion of `DelayedBug`/`GoodPathDelayedBug` to
// `Error` above.
Fatal | Error if self.treat_next_err_as_bug() => {
diagnostic.level = Bug;
}
DelayedBug(DelayedBugKind::Normal) => {
DelayedBug => {
// FIXME(eddyb) this should check for `has_errors` and stop pushing
// once *any* errors were emitted (and truncate `span_delayed_bugs`
// once *any* errors were emitted (and truncate `delayed_bugs`
// when an error is first emitted, also), but maybe there's a case
// in which that's not sound? otherwise this is really inefficient.
let backtrace = std::backtrace::Backtrace::capture();
self.span_delayed_bugs
.push(DelayedDiagnostic::with_backtrace(diagnostic, backtrace));
self.delayed_bugs.push(DelayedDiagnostic::with_backtrace(diagnostic, backtrace));
#[allow(deprecated)]
return Some(ErrorGuaranteed::unchecked_claim_error_was_emitted());
}
DelayedBug(DelayedBugKind::GoodPath) => {
GoodPathDelayedBug => {
let backtrace = std::backtrace::Backtrace::capture();
self.good_path_delayed_bugs
.push(DelayedDiagnostic::with_backtrace(diagnostic, backtrace));
@ -1392,12 +1386,12 @@ impl DiagCtxtInner {
fn flush_delayed(&mut self, kind: DelayedBugKind) {
let (bugs, note1) = match kind {
DelayedBugKind::Normal => (
std::mem::take(&mut self.span_delayed_bugs),
"no errors encountered even though `span_delayed_bug` issued",
std::mem::take(&mut self.delayed_bugs),
"no errors encountered even though delayed bugs were created",
),
DelayedBugKind::GoodPath => (
std::mem::take(&mut self.good_path_delayed_bugs),
"no warnings or errors encountered even though `good_path_delayed_bugs` issued",
"no warnings or errors encountered even though good path delayed bugs were created",
),
};
let note2 = "those delayed bugs will now be shown as internal compiler errors";
@ -1436,8 +1430,8 @@ impl DiagCtxtInner {
let mut bug =
if backtrace || self.ice_file.is_none() { bug.decorate() } else { bug.inner };
// "Undelay" the `DelayedBug`s (into plain `Bug`s).
if !matches!(bug.level, DelayedBug(_)) {
// "Undelay" the delayed bugs (into plain `Bug`s).
if !matches!(bug.level, DelayedBug | GoodPathDelayedBug) {
// NOTE(eddyb) not panicking here because we're already producing
// an ICE, and the more information the merrier.
bug.subdiagnostic(InvalidFlushedDelayedDiagnosticLevel {
@ -1503,85 +1497,89 @@ impl DelayedDiagnostic {
}
}
/// Level is_error EmissionGuarantee Top-level Sub Used in lints?
/// ----- -------- ----------------- --------- --- --------------
/// Bug yes BugAbort yes - -
/// Fatal yes FatalAbort/FatalError(*) yes - -
/// Error yes ErrorGuaranteed yes - yes
/// DelayedBug yes ErrorGuaranteed yes - -
/// GoodPathDelayedBug - () yes - -
/// ForceWarning - () yes - lint-only
/// Warning - () yes yes yes
/// Note - () rare yes -
/// OnceNote - () - yes lint-only
/// Help - () rare yes -
/// OnceHelp - () - yes lint-only
/// FailureNote - () rare - -
/// Allow - () yes - lint-only
/// Expect - () yes - lint-only
///
/// (*) `FatalAbort` normally, `FatalError` in the non-aborting "almost fatal" case that is
/// occasionally used.
///
#[derive(Copy, PartialEq, Eq, Clone, Hash, Debug, Encodable, Decodable)]
pub enum Level {
/// For bugs in the compiler. Manifests as an ICE (internal compiler error) panic.
///
/// Its `EmissionGuarantee` is `BugAbort`.
Bug,
/// An error that causes an immediate abort. Used for things like configuration errors,
/// internal overflows, some file operation errors.
Fatal,
/// An error in the code being compiled, which prevents compilation from finishing. This is the
/// most common case.
Error,
/// This is a strange one: lets you register an error without emitting it. If compilation ends
/// without any other errors occurring, this will be emitted as a bug. Otherwise, it will be
/// silently dropped. I.e. "expect other errors are emitted" semantics. Useful on code paths
/// that should only be reached when compiling erroneous code.
///
/// Its `EmissionGuarantee` is `ErrorGuaranteed` for `Normal` delayed bugs, and `()` for
/// `GoodPath` delayed bugs.
DelayedBug(DelayedBugKind),
DelayedBug,
/// An error that causes an immediate abort. Used for things like configuration errors,
/// internal overflows, some file operation errors.
/// Like `DelayedBug`, but weaker: lets you register an error without emitting it. If
/// compilation ends without any other diagnostics being emitted (and without an expected lint
/// being suppressed), this will be emitted as a bug. Otherwise, it will be silently dropped.
/// I.e. "expect other diagnostics are emitted (or suppressed)" semantics. Useful on code paths
/// that should only be reached when emitting diagnostics, e.g. for expensive one-time
/// diagnostic formatting operations.
///
/// Its `EmissionGuarantee` is `FatalAbort`, except in the non-aborting "almost fatal" case
/// that is occasionally used, where it is `FatalError`.
Fatal,
/// An error in the code being compiled, which prevents compilation from finishing. This is the
/// most common case.
///
/// Its `EmissionGuarantee` is `ErrorGuaranteed`.
Error,
/// FIXME(nnethercote) good path delayed bugs are semantically strange: if printed they produce
/// an ICE, but they don't satisfy `is_error` and they don't guarantee an error is emitted.
/// Plus there's the extra complication with expected (suppressed) lints. They have limited
/// use, and are used in very few places, and "good path" isn't a good name. It would be good
/// to remove them.
GoodPathDelayedBug,
/// A `force-warn` lint warning about the code being compiled. Does not prevent compilation
/// from finishing.
///
/// The [`LintExpectationId`] is used for expected lint diagnostics. In all other cases this
/// should be `None`.
///
/// Its `EmissionGuarantee` is `()`.
ForceWarning(Option<LintExpectationId>),
/// A warning about the code being compiled. Does not prevent compilation from finishing.
///
/// Its `EmissionGuarantee` is `()`.
Warning,
/// A message giving additional context. Rare, because notes are more commonly attached to other
/// diagnostics such as errors.
///
/// Its `EmissionGuarantee` is `()`.
/// A message giving additional context.
Note,
/// A note that is only emitted once. Rare, mostly used in circumstances relating to lints.
///
/// Its `EmissionGuarantee` is `()`.
/// A note that is only emitted once.
OnceNote,
/// A message suggesting how to fix something. Rare, because help messages are more commonly
/// attached to other diagnostics such as errors.
///
/// Its `EmissionGuarantee` is `()`.
/// A message suggesting how to fix something.
Help,
/// A help that is only emitted once. Rare.
///
/// Its `EmissionGuarantee` is `()`.
/// A help that is only emitted once.
OnceHelp,
/// Similar to `Note`, but used in cases where compilation has failed. When printed for human
/// consumption, it doesn't have any kind of `note:` label. Rare.
///
/// Its `EmissionGuarantee` is `()`.
/// consumption, it doesn't have any kind of `note:` label.
FailureNote,
/// Only used for lints.
///
/// Its `EmissionGuarantee` is `()`.
Allow,
/// Only used for lints.
///
/// Its `EmissionGuarantee` is `()`.
Expect(LintExpectationId),
}
@ -1595,7 +1593,7 @@ impl Level {
fn color(self) -> ColorSpec {
let mut spec = ColorSpec::new();
match self {
Bug | DelayedBug(_) | Fatal | Error => {
Bug | Fatal | Error | DelayedBug | GoodPathDelayedBug => {
spec.set_fg(Some(Color::Red)).set_intense(true);
}
ForceWarning(_) | Warning => {
@ -1615,7 +1613,7 @@ impl Level {
pub fn to_str(self) -> &'static str {
match self {
Bug | DelayedBug(_) => "error: internal compiler error",
Bug | DelayedBug | GoodPathDelayedBug => "error: internal compiler error",
Fatal | Error => "error",
ForceWarning(_) | Warning => "warning",
Note | OnceNote => "note",
@ -1635,6 +1633,19 @@ impl Level {
_ => None,
}
}
// Can this level be used in a top-level diagnostic message and/or a
// subdiagnostic message?
fn can_be_top_or_sub(&self) -> (bool, bool) {
match self {
Bug | DelayedBug | Fatal | Error | GoodPathDelayedBug | ForceWarning(_)
| FailureNote | Allow | Expect(_) => (true, false),
Warning | Note | Help => (true, true),
OnceNote | OnceHelp => (false, true),
}
}
}
// FIXME(eddyb) this doesn't belong here AFAICT, should be moved to callsite.

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@ -1,4 +1,4 @@
note: no errors encountered even though `span_delayed_bug` issued
note: no errors encountered even though delayed bugs were created
note: those delayed bugs will now be shown as internal compiler errors

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@ -1,4 +1,4 @@
note: no errors encountered even though `span_delayed_bug` issued
note: no errors encountered even though delayed bugs were created
note: those delayed bugs will now be shown as internal compiler errors