diff --git a/secondarywindow.h b/secondarywindow.h
index 19002de12..5f157fb6d 100644
--- a/secondarywindow.h
+++ b/secondarywindow.h
@@ -64,7 +64,7 @@ protected:
      *  last _visible_ secondary window is closed in case a system tray applet
      *  exists.
      */
-    virtual void closeEvent(QCloseEvent *);
+    virtual void closeEvent(QCloseEvent *) Q_DECL_OVERRIDE;
 };
 
 } // namespace KMail