diff --git a/panels/universal-access/cc-ua-panel.c b/panels/universal-access/cc-ua-panel.c
index 8dab68657..ed4c84219 100644
--- a/panels/universal-access/cc-ua-panel.c
+++ b/panels/universal-access/cc-ua-panel.c
@@ -117,7 +117,7 @@ cc_ua_panel_dispose (GObject *object)
   CcUaPanelPrivate *priv = CC_UA_PANEL (object)->priv;
 
   g_clear_object (&priv->builder);
-  g_slist_free_full (priv->toplevels, gtk_widget_destroy);
+  g_slist_free_full (priv->toplevels, (GDestroyNotify)gtk_widget_destroy);
   priv->toplevels = NULL;
 
   g_clear_object (&priv->wm_settings);