diff --git a/include/assimp/MemoryIOWrapper.h b/include/assimp/MemoryIOWrapper.h
index 720fd8424..77071e96f 100644
--- a/include/assimp/MemoryIOWrapper.h
+++ b/include/assimp/MemoryIOWrapper.h
@@ -125,7 +125,7 @@ public:
         return length;
     }
 
-    void Flush() {
+    void Flush() override{
         ai_assert(false); // won't be needed
     }