[clang] Fix const eval of constexpr-unknown relational comparisons. (#150088)

Like in other places, ignore the reference type of the base. (It might
make sense to refactor this at some point.)

Fixes #150015.

1 files changed, 4 insertions, 2 deletions

diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index 0d12161..9808298 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -14636,7 +14636,9 @@ EvaluateComparisonBinaryOperator(EvalInfo &Info, const BinaryOperator *E,
     if (!LHSDesignator.Invalid && !RHSDesignator.Invalid && IsRelational) {
       bool WasArrayIndex;
       unsigned Mismatch = FindDesignatorMismatch(
-          getType(LHSValue.Base), LHSDesignator, RHSDesignator, WasArrayIndex);
+          LHSValue.Base.isNull() ? QualType()
+                                 : getType(LHSValue.Base).getNonReferenceType(),
+          LHSDesignator, RHSDesignator, WasArrayIndex);
       // At the point where the designators diverge, the comparison has a
       // specified value if:
       //  - we are comparing array indices
@@ -14680,7 +14682,7 @@ EvaluateComparisonBinaryOperator(EvalInfo &Info, const BinaryOperator *E,
     // compare pointers within the object in question; otherwise, the result
     // depends on where the object is located in memory.
     if (!LHSValue.Base.isNull() && IsRelational) {
-      QualType BaseTy = getType(LHSValue.Base);
+      QualType BaseTy = getType(LHSValue.Base).getNonReferenceType();
       if (BaseTy->isIncompleteType())
         return Error(E);
       CharUnits Size = Info.Ctx.getTypeSizeInChars(BaseTy);