2 files changed, 19 insertions, 9 deletions

diff --git a/src/ir/gc-type-utils.h b/src/ir/gc-type-utils.h
index cec4490e2..abe5f2dfc 100644
--- a/src/ir/gc-type-utils.h
+++ b/src/ir/gc-type-utils.h
@@ -100,7 +100,7 @@ inline EvaluationResult evaluateKindCheck(Expression* curr) {
         expected = I31;
         break;
       default:
-        WASM_UNREACHABLE("unhandled BrOn");
+        WASM_UNREACHABLE("unhandled RefIs");
     }
     child = is->value;
   } else if (auto* as = curr->dynCast<RefAs>()) {
@@ -117,8 +117,12 @@ inline EvaluationResult evaluateKindCheck(Expression* curr) {
       case RefAsI31:
         expected = I31;
         break;
+      case ExternInternalize:
+      case ExternExternalize:
+        // These instructions can never be removed.
+        return Unknown;
       default:
-        WASM_UNREACHABLE("unhandled BrOn");
+        WASM_UNREACHABLE("unhandled RefAs");
     }
     child = as->value;
   } else {
diff --git a/test/lit/extern-conversions.wast b/test/lit/extern-conversions.wast
index 403b558f6..d3ad4d2d5 100644
--- a/test/lit/extern-conversions.wast
+++ b/test/lit/extern-conversions.wast
@@ -1,31 +1,37 @@
 ;; NOTE: Assertions have been generated by update_lit_checks.py --all-items and should not be edited.
 
 ;; Check that extern conversion instructions are emitted properly in the binary format.
+;; Also check that the optimizer does not break on this code.
+
+;; RUN: wasm-opt %s -all -O1 --roundtrip -S -o - | filecheck %s
 
-;; RUN: wasm-opt %s -all --roundtrip -S -o - | filecheck %s
 
 (module
  ;; CHECK:      (type $ref|any|_=>_ref|extern| (func (param (ref any)) (result (ref extern))))
 
  ;; CHECK:      (type $externref_=>_anyref (func (param externref) (result anyref)))
 
- ;; CHECK:      (func $extern.externalize (param $x (ref any)) (result (ref extern))
+ ;; CHECK:      (export "ext" (func $extern.externalize))
+
+ ;; CHECK:      (export "int" (func $extern.internalize))
+
+ ;; CHECK:      (func $extern.externalize (param $0 (ref any)) (result (ref extern))
  ;; CHECK-NEXT:  (extern.externalize
- ;; CHECK-NEXT:   (local.get $x)
+ ;; CHECK-NEXT:   (local.get $0)
  ;; CHECK-NEXT:  )
  ;; CHECK-NEXT: )
- (func $extern.externalize (param $x (ref any)) (result (ref extern))
+ (func $extern.externalize (export "ext") (param $x (ref any)) (result (ref extern))
   (extern.externalize
    (local.get $x)
   )
  )
 
- ;; CHECK:      (func $extern.internalize (param $x externref) (result anyref)
+ ;; CHECK:      (func $extern.internalize (param $0 externref) (result anyref)
  ;; CHECK-NEXT:  (extern.internalize
- ;; CHECK-NEXT:   (local.get $x)
+ ;; CHECK-NEXT:   (local.get $0)
  ;; CHECK-NEXT:  )
  ;; CHECK-NEXT: )
- (func $extern.internalize (param $x (ref null extern)) (result (ref null any))
+ (func $extern.internalize (export "int") (param $x (ref null extern)) (result (ref null any))
   (extern.internalize
    (local.get $x)
   )