1 files changed, 49 insertions, 4 deletions

diff --git a/compiler/rustc_lint/src/expect.rs b/compiler/rustc_lint/src/expect.rs
index 42b33f9882d..d8afba3d505 100644
--- a/compiler/rustc_lint/src/expect.rs
+++ b/compiler/rustc_lint/src/expect.rs
@@ -1,21 +1,66 @@
+use rustc_data_structures::fx::FxIndexMap;
+use rustc_hir::{HirId, CRATE_OWNER_ID};
+use rustc_middle::lint::LintExpectation;
 use rustc_middle::query::Providers;
 use rustc_middle::ty::TyCtxt;
 use rustc_session::lint::builtin::UNFULFILLED_LINT_EXPECTATIONS;
-use rustc_session::lint::LintExpectationId;
+use rustc_session::lint::{Level, LintExpectationId};
 use rustc_span::Symbol;
 
 use crate::lints::{Expectation, ExpectationNote};
 
 pub(crate) fn provide(providers: &mut Providers) {
-    *providers = Providers { check_expectations, ..*providers };
+    *providers = Providers { lint_expectations, check_expectations, ..*providers };
+}
+
+fn lint_expectations(tcx: TyCtxt<'_>, (): ()) -> Vec<(LintExpectationId, LintExpectation)> {
+    let krate = tcx.hir_crate_items(());
+
+    let mut expectations = Vec::new();
+    let mut unstable_to_stable_ids = FxIndexMap::default();
+
+    let mut record_stable = |attr_id, hir_id, attr_index| {
+        let expect_id = LintExpectationId::Stable { hir_id, attr_index, lint_index: None };
+        unstable_to_stable_ids.entry(attr_id).or_insert(expect_id);
+    };
+    let mut push_expectations = |owner| {
+        let lints = tcx.shallow_lint_levels_on(owner);
+        if lints.expectations.is_empty() {
+            return;
+        }
+
+        expectations.extend_from_slice(&lints.expectations);
+
+        let attrs = tcx.hir_attrs(owner);
+        for &(local_id, attrs) in attrs.map.iter() {
+            // Some attributes appear multiple times in HIR, to ensure they are correctly taken
+            // into account where they matter. This means we cannot just associate the AttrId to
+            // the first HirId where we see it, but need to check it actually appears in a lint
+            // level.
+            // FIXME(cjgillot): Can this cause an attribute to appear in multiple expectation ids?
+            if !lints.specs.contains_key(&local_id) {
+                continue;
+            }
+            for (attr_index, attr) in attrs.iter().enumerate() {
+                let Some(Level::Expect(_)) = Level::from_attr(attr) else { continue };
+                record_stable(attr.id, HirId { owner, local_id }, attr_index.try_into().unwrap());
+            }
+        }
+    };
+
+    push_expectations(CRATE_OWNER_ID);
+    for owner in krate.owners() {
+        push_expectations(owner);
+    }
+
+    tcx.dcx().update_unstable_expectation_id(unstable_to_stable_ids);
+    expectations
 }
 
 fn check_expectations(tcx: TyCtxt<'_>, tool_filter: Option<Symbol>) {
     let lint_expectations = tcx.lint_expectations(());
     let fulfilled_expectations = tcx.dcx().steal_fulfilled_expectation_ids();
 
-    tracing::debug!(?lint_expectations, ?fulfilled_expectations);
-
     for (id, expectation) in lint_expectations {
         // This check will always be true, since `lint_expectations` only
         // holds stable ids