diff --git a/js/src/jit/JitFrameIterator.h b/js/src/jit/JitFrameIterator.h
index 636bbd4b0a89..89a923f3891a 100644
--- a/js/src/jit/JitFrameIterator.h
+++ b/js/src/jit/JitFrameIterator.h
@@ -266,8 +266,6 @@ class JitFrameIterator
 #endif
 };
 
-class IonJSFrameLayout;
-
 class RResumePoint;
 
 // Reads frame information in snapshot-encoding order (that is, outermost frame