diff --git a/src/plugins/coreplugin/navigationwidget.cpp b/src/plugins/coreplugin/navigationwidget.cpp
index 811e51ac8ed..3f4ee681cd5 100644
--- a/src/plugins/coreplugin/navigationwidget.cpp
+++ b/src/plugins/coreplugin/navigationwidget.cpp
@@ -178,7 +178,7 @@ NavigationWidget *NavigationWidget::instance()
     return NavigationWidgetPrivate::m_instance;
 }
 
-void NavigationWidget::setFactories(const QList<INavigationWidgetFactory *> factories)
+void NavigationWidget::setFactories(const QList<INavigationWidgetFactory *> &factories)
 {
     Context navicontext(Core::Constants::C_NAVIGATION_PANE);
 
diff --git a/src/plugins/coreplugin/navigationwidget.h b/src/plugins/coreplugin/navigationwidget.h
index f353f535aca..8f638c51904 100644
--- a/src/plugins/coreplugin/navigationwidget.h
+++ b/src/plugins/coreplugin/navigationwidget.h
@@ -85,7 +85,7 @@ public:
     explicit NavigationWidget(QAction *toggleSideBarAction);
     virtual ~NavigationWidget();
 
-    void setFactories(const QList<INavigationWidgetFactory*> factories);
+    void setFactories(const QList<INavigationWidgetFactory*> &factories);
 
     void saveSettings(QSettings *settings);
     void restoreSettings(QSettings *settings);