diff --git a/kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/ObjCInterop.kt b/kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/ObjCInterop.kt
index 1dea177f2c8..5c9bfe002e8 100644
--- a/kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/ObjCInterop.kt
+++ b/kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/ObjCInterop.kt
@@ -62,7 +62,7 @@ fun ClassDescriptor.isExternalObjCClass(): Boolean = this.isObjCClass() &&
             it.annotations.findAnnotation(externalObjCClassFqName) != null
         }
 fun IrClass.isExternalObjCClass(): Boolean = this.isObjCClass() &&
-        (this as IrDeclaration).parentDeclarationsWithSelf.filterIsInstance<IrClass>().any {
+        this.parentDeclarationsWithSelf.filterIsInstance<IrClass>().any {
             it.annotations.hasAnnotation(externalObjCClassFqName)
         }