diff --git a/src/corelib/tools/qfunctionaltools_impl.h b/src/corelib/tools/qfunctionaltools_impl.h
index 5878b90bd6a..0942d5fe7d8 100644
--- a/src/corelib/tools/qfunctionaltools_impl.h
+++ b/src/corelib/tools/qfunctionaltools_impl.h
@@ -42,6 +42,7 @@ struct StorageByValue
 template <typename Object, typename Tag = void>
 struct StorageEmptyBaseClassOptimization : Object
 {
+    StorageEmptyBaseClassOptimization() = default;
     StorageEmptyBaseClassOptimization(Object &&o)
         : Object(std::move(o))
     {}