1 files changed, 7 insertions, 3 deletions
diff --git a/src/ir/gc-type-utils.h b/src/ir/gc-type-utils.h
index 6ac604ad2..8832d4d0f 100644
--- a/src/ir/gc-type-utils.h
+++ b/src/ir/gc-type-utils.h
@@ -61,9 +61,13 @@ inline EvaluationResult evaluateKindCheck(Expression* curr) {
         if (Type::isSubType(br->ref->type, br->castType)) {
           return flip ? Failure : Success;
         }
-        // If the cast type is unrelated to the type we have, the cast will
-        // certainly fail.
-        if (!Type::isSubType(br->castType, br->ref->type)) {
+        // If the cast type is unrelated to the type we have and it's not
+        // possible for the cast to succeed anyway because the value is null,
+        // then the cast will certainly fail. TODO: This is essentially the same
+        // as `canBeCastTo` in OptimizeInstructions. Find a way to deduplicate
+        // this logic.
+        if (!Type::isSubType(br->castType, br->ref->type) &&
+            (br->castType.isNonNullable() || br->ref->type.isNonNullable())) {
           return flip ? Success : Failure;
         }
         return Unknown;