Auto merge of #121036 - matthiaskrgr:rollup-ul05q8e, r=matthiaskrgr

Rollup of 8 pull requests

Successful merges:

 - #114877 (unstable-book: add quick-edit link)
 - #120548 (rustdoc: Fix handling of doc_auto_cfg feature for cfg attributes on glob reexport)
 - #120549 (modify alias-relate to also normalize ambiguous opaques)
 - #120959 (Remove good path delayed bugs)
 - #120978 (match lowering: simplify block creation)
 - #121019 (coverage: Simplify some parts of the coverage span refiner)
 - #121021 (Extend intra-doc link chapter in the rustdoc book)
 - #121031 (RustWrapper: adapt for coverage mapping API changes)

Failed merges:

 - #121014 (Remove `force_print_diagnostic`)

r? `@ghost`
`@rustbot` modify labels: rollup

compiler/rustc_const_eval/src/interpret/eval_context.rs

@@ -288,7 +288,7 @@ impl<'tcx> fmt::Display for FrameInfo<'tcx> {
             if tcx.def_key(self.instance.def_id()).disambiguated_data.data == DefPathData::Closure {
                 write!(f, "inside closure")
             } else {
-                // Note: this triggers a `good_path_delayed_bug` state, which means that if we ever
+                // Note: this triggers a `must_produce_diag` state, which means that if we ever
                 // get here we must emit a diagnostic. We should never display a `FrameInfo` unless
                 // we actually want to emit a warning or error to the user.
                 write!(f, "inside `{}`", self.instance)
@@ -304,7 +304,7 @@ impl<'tcx> FrameInfo<'tcx> {
             errors::FrameNote { where_: "closure", span, instance: String::new(), times: 0 }
         } else {
             let instance = format!("{}", self.instance);
-            // Note: this triggers a `good_path_delayed_bug` state, which means that if we ever get
+            // Note: this triggers a `must_produce_diag` state, which means that if we ever get
             // here we must emit a diagnostic. We should never display a `FrameInfo` unless we
             // actually want to emit a warning or error to the user.
             errors::FrameNote { where_: "instance", span, instance, times: 0 }

compiler/rustc_error_messages/src/lib.rs

@@ -376,7 +376,7 @@ impl From<Cow<'static, str>> for DiagnosticMessage {
     }
 }
 
-/// A workaround for good_path_delayed_bug ICEs when formatting types in disabled lints.
+/// A workaround for must_produce_diag ICEs when formatting types in disabled lints.
 ///
 /// Delays formatting until `.into(): DiagnosticMessage` is used.
 pub struct DelayDm<F>(pub F);

compiler/rustc_errors/src/annotate_snippet_emitter_writer.rs

@@ -85,11 +85,7 @@ 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::Fatal
-        | Level::Error
-        | Level::DelayedBug
-        | Level::GoodPathDelayedBug => AnnotationType::Error,
+        Level::Bug | Level::Fatal | Level::Error | Level::DelayedBug => AnnotationType::Error,
         Level::ForceWarning(_) | Level::Warning => AnnotationType::Warning,
         Level::Note | Level::OnceNote => AnnotationType::Note,
         Level::Help | Level::OnceHelp => AnnotationType::Help,

compiler/rustc_errors/src/diagnostic.rs

@@ -237,8 +237,7 @@ impl Diagnostic {
         match self.level {
             Level::Bug | Level::Fatal | Level::Error | Level::DelayedBug => true,
 
-            Level::GoodPathDelayedBug
-            | Level::ForceWarning(_)
+            Level::ForceWarning(_)
             | Level::Warning
             | Level::Note
             | Level::OnceNote

compiler/rustc_errors/src/lib.rs

@@ -435,7 +435,6 @@ struct DiagCtxtInner {
     lint_err_guars: Vec<ErrorGuaranteed>,
     /// The delayed bugs and their error guarantees.
     delayed_bugs: Vec<(DelayedDiagnostic, ErrorGuaranteed)>,
-    good_path_delayed_bugs: Vec<DelayedDiagnostic>,
 
     /// The number of stashed errors. Unlike the other counts, this can go up
     /// and down, so it doesn't guarantee anything.
@@ -446,13 +445,18 @@ struct DiagCtxtInner {
     /// The warning count shown to the user at the end.
     deduplicated_warn_count: usize,
 
+    emitter: Box<DynEmitter>,
+
+    /// Must we produce a diagnostic to justify the use of the expensive
+    /// `trimmed_def_paths` function?
+    must_produce_diag: bool,
+
     /// Has this diagnostic context printed any diagnostics? (I.e. has
     /// `self.emitter.emit_diagnostic()` been called?
     has_printed: bool,
 
-    emitter: Box<DynEmitter>,
     /// This flag indicates that an expected diagnostic was emitted and suppressed.
-    /// This is used for the `good_path_delayed_bugs` check.
+    /// This is used for the `must_produce_diag` check.
     suppressed_expected_diag: bool,
 
     /// This set contains the code of all emitted diagnostics to avoid
@@ -533,11 +537,6 @@ 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 _));
 
-enum DelayedBugKind {
-    Normal,
-    GoodPath,
-}
-
 #[derive(Copy, Clone, Default)]
 pub struct DiagCtxtFlags {
     /// If false, warning-level lints are suppressed.
@@ -563,11 +562,16 @@ impl Drop for DiagCtxtInner {
         self.emit_stashed_diagnostics();
 
         if self.err_guars.is_empty() {
-            self.flush_delayed(DelayedBugKind::Normal)
+            self.flush_delayed()
         }
 
         if !self.has_printed && !self.suppressed_expected_diag && !std::thread::panicking() {
-            self.flush_delayed(DelayedBugKind::GoodPath);
+            if self.must_produce_diag {
+                panic!(
+                    "must_produce_diag: trimmed_def_paths called but no diagnostics emitted; \
+                       use `DelayDm` for lints or `with_no_trimmed_paths` for debugging"
+                );
+            }
         }
 
         if self.check_unstable_expect_diagnostics {
@@ -609,12 +613,12 @@ impl DiagCtxt {
                 err_guars: Vec::new(),
                 lint_err_guars: Vec::new(),
                 delayed_bugs: Vec::new(),
-                good_path_delayed_bugs: Vec::new(),
                 stashed_err_count: 0,
                 deduplicated_err_count: 0,
                 deduplicated_warn_count: 0,
-                has_printed: false,
                 emitter,
+                must_produce_diag: false,
+                has_printed: false,
                 suppressed_expected_diag: false,
                 taught_diagnostics: Default::default(),
                 emitted_diagnostic_codes: Default::default(),
@@ -666,13 +670,14 @@ impl DiagCtxt {
         inner.stashed_err_count = 0;
         inner.deduplicated_err_count = 0;
         inner.deduplicated_warn_count = 0;
+        inner.must_produce_diag = false;
         inner.has_printed = false;
+        inner.suppressed_expected_diag = false;
 
         // actually free the underlying memory (which `clear` would not do)
         inner.err_guars = Default::default();
         inner.lint_err_guars = 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();
         inner.emitted_diagnostics = Default::default();
@@ -934,7 +939,13 @@ impl DiagCtxt {
     }
 
     pub fn flush_delayed(&self) {
-        self.inner.borrow_mut().flush_delayed(DelayedBugKind::Normal);
+        self.inner.borrow_mut().flush_delayed();
+    }
+
+    /// Used when trimmed_def_paths is called and we must produce a diagnostic
+    /// to justify its cost.
+    pub fn set_must_produce_diag(&self) {
+        self.inner.borrow_mut().must_produce_diag = true;
     }
 }
 
@@ -1108,13 +1119,6 @@ impl DiagCtxt {
         DiagnosticBuilder::<ErrorGuaranteed>::new(self, DelayedBug, msg).with_span(sp).emit()
     }
 
-    /// Ensures that a diagnostic is printed. See `Level::GoodPathDelayedBug`.
-    // No `#[rustc_lint_diagnostics]` because bug messages aren't user-facing.
-    #[track_caller]
-    pub fn good_path_delayed_bug(&self, msg: impl Into<DiagnosticMessage>) {
-        DiagnosticBuilder::<()>::new(self, GoodPathDelayedBug, msg).emit()
-    }
-
     #[rustc_lint_diagnostics]
     #[track_caller]
     pub fn struct_warn(&self, msg: impl Into<DiagnosticMessage>) -> DiagnosticBuilder<'_, ()> {
@@ -1266,19 +1270,17 @@ impl DiagCtxtInner {
         if diagnostic.has_future_breakage() {
             // Future breakages aren't emitted if they're Level::Allow,
             // but they still need to be constructed and stashed below,
-            // so they'll trigger the good-path bug check.
+            // so they'll trigger the must_produce_diag check.
             self.suppressed_expected_diag = true;
             self.future_breakage_diagnostics.push(diagnostic.clone());
         }
 
-        if matches!(diagnostic.level, DelayedBug | GoodPathDelayedBug)
-            && self.flags.eagerly_emit_delayed_bugs
-        {
+        if diagnostic.level == DelayedBug && self.flags.eagerly_emit_delayed_bugs {
             diagnostic.level = Error;
         }
 
         match diagnostic.level {
-            // This must come after the possible promotion of `DelayedBug`/`GoodPathDelayedBug` to
+            // This must come after the possible promotion of `DelayedBug` to
             // `Error` above.
             Fatal | Error if self.treat_next_err_as_bug() => {
                 diagnostic.level = Bug;
@@ -1297,12 +1299,6 @@ impl DiagCtxtInner {
                     .push((DelayedDiagnostic::with_backtrace(diagnostic, backtrace), guar));
                 return Some(guar);
             }
-            GoodPathDelayedBug => {
-                let backtrace = std::backtrace::Backtrace::capture();
-                self.good_path_delayed_bugs
-                    .push(DelayedDiagnostic::with_backtrace(diagnostic, backtrace));
-                return None;
-            }
             Warning if !self.flags.can_emit_warnings => {
                 if diagnostic.has_future_breakage() {
                     (*TRACK_DIAGNOSTIC)(diagnostic, &mut |_| {});
@@ -1414,23 +1410,14 @@ impl DiagCtxtInner {
         self.emit_diagnostic(Diagnostic::new(FailureNote, msg));
     }
 
-    fn flush_delayed(&mut self, kind: DelayedBugKind) {
-        let (bugs, note1) = match kind {
-            DelayedBugKind::Normal => (
-                std::mem::take(&mut self.delayed_bugs).into_iter().map(|(b, _)| b).collect(),
-                "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 were created",
-            ),
-        };
-        let note2 = "those delayed bugs will now be shown as internal compiler errors";
-
-        if bugs.is_empty() {
+    fn flush_delayed(&mut self) {
+        if self.delayed_bugs.is_empty() {
             return;
         }
 
+        let bugs: Vec<_> =
+            std::mem::take(&mut self.delayed_bugs).into_iter().map(|(b, _)| b).collect();
+
         // If backtraces are enabled, also print the query stack
         let backtrace = std::env::var_os("RUST_BACKTRACE").map_or(true, |x| &x != "0");
         for (i, bug) in bugs.into_iter().enumerate() {
@@ -1454,6 +1441,8 @@ impl DiagCtxtInner {
                 // frame them better (e.g. separate warnings from them). Also,
                 // make it a note so it doesn't count as an error, because that
                 // could trigger `-Ztreat-err-as-bug`, which we don't want.
+                let note1 = "no errors encountered even though delayed bugs were created";
+                let note2 = "those delayed bugs will now be shown as internal compiler errors";
                 self.emit_diagnostic(Diagnostic::new(Note, note1));
                 self.emit_diagnostic(Diagnostic::new(Note, note2));
             }
@@ -1462,7 +1451,7 @@ impl DiagCtxtInner {
                 if backtrace || self.ice_file.is_none() { bug.decorate() } else { bug.inner };
 
             // "Undelay" the delayed bugs (into plain `Bug`s).
-            if !matches!(bug.level, DelayedBug | GoodPathDelayedBug) {
+            if bug.level != DelayedBug {
                 // NOTE(eddyb) not panicking here because we're already producing
                 // an ICE, and the more information the merrier.
                 bug.subdiagnostic(InvalidFlushedDelayedDiagnosticLevel {
@@ -1534,7 +1523,6 @@ impl DelayedDiagnostic {
 /// 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   -
@@ -1567,20 +1555,6 @@ pub enum Level {
     /// that should only be reached when compiling erroneous code.
     DelayedBug,
 
-    /// 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.
-    ///
-    /// 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.
     ///
@@ -1625,7 +1599,7 @@ impl Level {
     fn color(self) -> ColorSpec {
         let mut spec = ColorSpec::new();
         match self {
-            Bug | Fatal | Error | DelayedBug | GoodPathDelayedBug => {
+            Bug | Fatal | Error | DelayedBug => {
                 spec.set_fg(Some(Color::Red)).set_intense(true);
             }
             ForceWarning(_) | Warning => {
@@ -1645,7 +1619,7 @@ impl Level {
 
     pub fn to_str(self) -> &'static str {
         match self {
-            Bug | DelayedBug | GoodPathDelayedBug => "error: internal compiler error",
+            Bug | DelayedBug => "error: internal compiler error",
             Fatal | Error => "error",
             ForceWarning(_) | Warning => "warning",
             Note | OnceNote => "note",
@@ -1670,8 +1644,8 @@ impl Level {
     // subdiagnostic message?
     fn can_be_top_or_sub(&self) -> (bool, bool) {
         match self {
-            Bug | DelayedBug | Fatal | Error | GoodPathDelayedBug | ForceWarning(_)
-            | FailureNote | Allow | Expect(_) => (true, false),
+            Bug | DelayedBug | Fatal | Error | ForceWarning(_) | FailureNote | Allow
+            | Expect(_) => (true, false),
 
             Warning | Note | Help => (true, true),
 

compiler/rustc_hir_typeck/src/lib.rs

@@ -304,6 +304,10 @@ fn typeck_with_fallback<'tcx>(
 
     let typeck_results = fcx.resolve_type_vars_in_body(body);
 
+    // We clone the defined opaque types during writeback in the new solver
+    // because we have to use them during normalization.
+    let _ = fcx.infcx.take_opaque_types();
+
     // Consistency check our TypeckResults instance can hold all ItemLocalIds
     // it will need to hold.
     assert_eq!(typeck_results.hir_owner, id.owner);

compiler/rustc_hir_typeck/src/writeback.rs

@@ -562,7 +562,15 @@ impl<'cx, 'tcx> WritebackCx<'cx, 'tcx> {
 
     #[instrument(skip(self), level = "debug")]
     fn visit_opaque_types(&mut self) {
-        let opaque_types = self.fcx.infcx.take_opaque_types();
+        // We clone the opaques instead of stealing them here as they are still used for
+        // normalization in the next generation trait solver.
+        //
+        // FIXME(-Znext-solver): Opaque types defined after this would simply get dropped
+        // at the end of typeck. While this seems unlikely to happen in practice this
+        // should still get fixed. Either by preventing writeback from defining new opaque
+        // types or by using this function at the end of writeback and running it as a
+        // fixpoint.
+        let opaque_types = self.fcx.infcx.clone_opaque_types();
         for (opaque_type_key, decl) in opaque_types {
             let hidden_type = self.resolve(decl.hidden_type, &decl.hidden_type.span);
             let opaque_type_key = self.resolve(opaque_type_key, &decl.hidden_type.span);

compiler/rustc_infer/src/infer/error_reporting/mod.rs

@@ -132,20 +132,6 @@ pub struct TypeErrCtxt<'a, 'tcx> {
         Box<dyn Fn(Ty<'tcx>) -> Vec<(Ty<'tcx>, Vec<PredicateObligation<'tcx>>)> + 'a>,
 }
 
-impl Drop for TypeErrCtxt<'_, '_> {
-    fn drop(&mut self) {
-        if self.dcx().has_errors().is_some() {
-            // Ok, emitted an error.
-        } else {
-            // Didn't emit an error; maybe it was created but not yet emitted.
-            self.infcx
-                .tcx
-                .sess
-                .good_path_delayed_bug("used a `TypeErrCtxt` without raising an error or lint");
-        }
-    }
-}
-
 impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
     pub fn dcx(&self) -> &'tcx DiagCtxt {
         self.infcx.tcx.dcx()

compiler/rustc_infer/src/infer/mod.rs

@@ -1325,6 +1325,12 @@ impl<'tcx> InferCtxt<'tcx> {
         std::mem::take(&mut self.inner.borrow_mut().opaque_type_storage.opaque_types)
     }
 
+    #[instrument(level = "debug", skip(self), ret)]
+    pub fn clone_opaque_types(&self) -> opaque_types::OpaqueTypeMap<'tcx> {
+        debug_assert_ne!(self.defining_use_anchor, DefiningAnchor::Error);
+        self.inner.borrow().opaque_type_storage.opaque_types.clone()
+    }
+
     pub fn ty_to_string(&self, t: Ty<'tcx>) -> String {
         self.resolve_vars_if_possible(t).to_string()
     }

compiler/rustc_llvm/llvm-wrapper/CoverageMappingWrapper.cpp

@@ -139,7 +139,7 @@ extern "C" void LLVMRustCoverageWriteMappingToBuffer(
            RustMappingRegions, NumMappingRegions)) {
     MappingRegions.emplace_back(
         fromRust(Region.Count), fromRust(Region.FalseCount),
-#if LLVM_VERSION_GE(18, 0)
+#if LLVM_VERSION_GE(18, 0) && LLVM_VERSION_LT(19, 0)
         coverage::CounterMappingRegion::MCDCParameters{},
 #endif
         Region.FileID, Region.ExpandedFileID,