diff --git a/db/db_test_util.h b/db/db_test_util.h
index b335cf184..8b22eee5f 100644
--- a/db/db_test_util.h
+++ b/db/db_test_util.h
@@ -184,7 +184,7 @@ class SpecialSkipListFactory : public MemTableRepFactory {
 
   virtual MemTableRep* CreateMemTableRep(
       const MemTableRep::KeyComparator& compare, MemTableAllocator* allocator,
-      const SliceTransform* transform, Logger* logger) {
+      const SliceTransform* transform, Logger* logger) override {
     return new SpecialMemTableRep(
         allocator, factory_.CreateMemTableRep(compare, allocator, transform, 0),
         num_entries_flush_);