Use AttrId key for unstable<->stable expectation map.

Author: cjgillot

compiler/rustc_errors/src/diagnostic.rs

@@ -10,7 +10,7 @@ use rustc_lint_defs::{Applicability, LintExpectationId};
 use rustc_macros::{Decodable, Encodable};
 use rustc_span::source_map::Spanned;
 use rustc_span::symbol::Symbol;
-use rustc_span::{Span, DUMMY_SP};
+use rustc_span::{AttrId, Span, DUMMY_SP};
 use std::borrow::Cow;
 use std::fmt::{self, Debug};
 use std::hash::{Hash, Hasher};
@@ -355,24 +355,19 @@ impl DiagInner {
 
     pub(crate) fn update_unstable_expectation_id(
         &mut self,
-        unstable_to_stable: &FxIndexMap<LintExpectationId, LintExpectationId>,
+        unstable_to_stable: &FxIndexMap<AttrId, LintExpectationId>,
     ) {
         if let Level::Expect(expectation_id) | Level::ForceWarning(Some(expectation_id)) =
             &mut self.level
+            && let LintExpectationId::Unstable { attr_id, lint_index } = *expectation_id
         {
-            if expectation_id.is_stable() {
-                return;
-            }
-
             // The unstable to stable map only maps the unstable `AttrId` to a stable `HirId` with an attribute index.
             // The lint index inside the attribute is manually transferred here.
-            let lint_index = expectation_id.get_lint_index();
-            expectation_id.set_lint_index(None);
-            let mut stable_id = unstable_to_stable
-                .get(expectation_id)
-                .expect("each unstable `LintExpectationId` must have a matching stable id")
-                .normalize();
+            let Some(stable_id) = unstable_to_stable.get(&attr_id) else {
+                panic!("{expectation_id:?} must have a matching stable id")
+            };
 
+            let mut stable_id = stable_id.normalize();
             stable_id.set_lint_index(lint_index);
             *expectation_id = stable_id;
         }

compiler/rustc_errors/src/lib.rs

@@ -60,7 +60,7 @@ use rustc_data_structures::AtomicRef;
 use rustc_lint_defs::LintExpectationId;
 use rustc_macros::{Decodable, Encodable};
 use rustc_span::source_map::SourceMap;
-use rustc_span::{Loc, Span, DUMMY_SP};
+use rustc_span::{AttrId, Loc, Span, DUMMY_SP};
 use std::backtrace::{Backtrace, BacktraceStatus};
 use std::borrow::Cow;
 use std::cell::Cell;
@@ -1085,7 +1085,7 @@ impl<'a> DiagCtxtHandle<'a> {
 
     pub fn update_unstable_expectation_id(
         &self,
-        unstable_to_stable: &FxIndexMap<LintExpectationId, LintExpectationId>,
+        unstable_to_stable: FxIndexMap<AttrId, LintExpectationId>,
     ) {
         let mut inner = self.inner.borrow_mut();
         let diags = std::mem::take(&mut inner.unstable_expect_diagnostics);
@@ -1094,7 +1094,7 @@ impl<'a> DiagCtxtHandle<'a> {
         if !diags.is_empty() {
             inner.suppressed_expected_diag = true;
             for mut diag in diags.into_iter() {
-                diag.update_unstable_expectation_id(unstable_to_stable);
+                diag.update_unstable_expectation_id(&unstable_to_stable);
 
                 // Here the diagnostic is given back to `emit_diagnostic` where it was first
                 // intercepted. Now it should be processed as usual, since the unstable expectation
@@ -1106,11 +1106,11 @@ impl<'a> DiagCtxtHandle<'a> {
         inner
             .stashed_diagnostics
             .values_mut()
-            .for_each(|(diag, _guar)| 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()
-            .for_each(|diag| diag.update_unstable_expectation_id(unstable_to_stable));
+            .for_each(|diag| diag.update_unstable_expectation_id(&unstable_to_stable));
     }
 
     /// This methods steals all [`LintExpectationId`]s that are stored inside

compiler/rustc_lint/src/levels.rs

@@ -39,7 +39,7 @@ use rustc_session::lint::{
 };
 use rustc_session::Session;
 use rustc_span::symbol::{sym, Symbol};
-use rustc_span::{Span, DUMMY_SP};
+use rustc_span::{AttrId, Span, DUMMY_SP};
 use tracing::{debug, instrument};
 
 use crate::errors::{
@@ -146,7 +146,7 @@ fn lint_expectations(tcx: TyCtxt<'_>, (): ()) -> Vec<(LintExpectationId, LintExp
     builder.add_id(hir::CRATE_HIR_ID);
     tcx.hir().walk_toplevel_module(&mut builder);
 
-    tcx.dcx().update_unstable_expectation_id(&builder.provider.unstable_to_stable_ids);
+    tcx.dcx().update_unstable_expectation_id(builder.provider.unstable_to_stable_ids);
 
     builder.provider.expectations
 }
@@ -260,7 +260,7 @@ struct QueryMapExpectationsWrapper<'tcx> {
     /// Level map for `cur`.
     specs: ShallowLintLevelMap,
     expectations: Vec<(LintExpectationId, LintExpectation)>,
-    unstable_to_stable_ids: FxIndexMap<LintExpectationId, LintExpectationId>,
+    unstable_to_stable_ids: FxIndexMap<AttrId, LintExpectationId>,
     /// Empty hash map to simplify code.
     empty: FxIndexMap<LintId, LevelAndSource>,
 }
@@ -282,9 +282,8 @@ impl LintLevelsProvider for QueryMapExpectationsWrapper<'_> {
         else {
             bug!("unstable expectation id should already be mapped")
         };
-        let key = LintExpectationId::Unstable { attr_id, lint_index: None };
 
-        self.unstable_to_stable_ids.entry(key).or_insert(LintExpectationId::Stable {
+        self.unstable_to_stable_ids.entry(attr_id).or_insert(LintExpectationId::Stable {
             hir_id,
             attr_index,
             lint_index: None,