3 files changed, 15 insertions, 4 deletions
diff --git a/compiler/rustc_const_eval/src/interpret/projection.rs b/compiler/rustc_const_eval/src/interpret/projection.rs
index 3a441c1d649..7b68a37fdf3 100644
--- a/compiler/rustc_const_eval/src/interpret/projection.rs
+++ b/compiler/rustc_const_eval/src/interpret/projection.rs
@@ -149,6 +149,8 @@ where
             "`field` projection called on a slice -- call `index` projection instead"
         );
         let offset = base.layout().fields.offset(field);
+        // Computing the layout does normalization, so we get a normalized type out of this
+        // even if the field type is non-normalized (possible e.g. via associated types).
         let field_layout = base.layout().field(self, field);
 
         // Offset may need adjustment for unsized fields.
diff --git a/compiler/rustc_const_eval/src/interpret/visitor.rs b/compiler/rustc_const_eval/src/interpret/visitor.rs
index de0590a4b14..340a496a689 100644
--- a/compiler/rustc_const_eval/src/interpret/visitor.rs
+++ b/compiler/rustc_const_eval/src/interpret/visitor.rs
@@ -153,6 +153,16 @@ pub trait ValueVisitor<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>>: Sized {
                 // We visited all parts of this one.
                 return Ok(());
             }
+
+            // Non-normalized types should never show up here.
+            ty::Param(..)
+            | ty::Alias(..)
+            | ty::Bound(..)
+            | ty::Placeholder(..)
+            | ty::Infer(..)
+            | ty::Error(..) => throw_inval!(TooGeneric),
+
+            // The rest is handled below.
             _ => {}
         };
 
diff --git a/compiler/rustc_const_eval/src/transform/check_consts/mod.rs b/compiler/rustc_const_eval/src/transform/check_consts/mod.rs
index 98276ff2e68..1be2a2bc1f3 100644
--- a/compiler/rustc_const_eval/src/transform/check_consts/mod.rs
+++ b/compiler/rustc_const_eval/src/transform/check_consts/mod.rs
@@ -131,11 +131,10 @@ fn is_parent_const_stable_trait(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
     let local_def_id = def_id.expect_local();
     let hir_id = tcx.local_def_id_to_hir_id(local_def_id);
 
-    let Some(parent) = tcx.hir().opt_parent_id(hir_id) else { return false };
-
-    if !tcx.is_const_trait_impl_raw(parent.owner.def_id.to_def_id()) {
+    let parent_owner_id = tcx.parent_hir_id(hir_id).owner;
+    if !tcx.is_const_trait_impl_raw(parent_owner_id.to_def_id()) {
         return false;
     }
 
-    tcx.lookup_const_stability(parent.owner).is_some_and(|stab| stab.is_const_stable())
+    tcx.lookup_const_stability(parent_owner_id).is_some_and(|stab| stab.is_const_stable())
 }