diff --git a/gtk/gtkwindow.c b/gtk/gtkwindow.c
index de2057b9bb..32b958abc1 100644
--- a/gtk/gtkwindow.c
+++ b/gtk/gtkwindow.c
@@ -11872,7 +11872,7 @@ warn_response (GtkDialog *dialog,
                gint       response)
 {
   gtk_widget_destroy (GTK_WIDGET (dialog));
-  g_object_set_data (inspector_window, "warning_dialog", NULL);
+  g_object_set_data (G_OBJECT (inspector_window), "warning_dialog", NULL);
   if (response == GTK_RESPONSE_NO)
     {
       gtk_widget_destroy (inspector_window);
@@ -11914,11 +11914,11 @@ gtk_window_set_debugging (gboolean enable,
           gtk_dialog_add_button (GTK_DIALOG (dialog), _("_Cancel"), GTK_RESPONSE_NO);
           gtk_dialog_add_button (GTK_DIALOG (dialog), _("_OK"), GTK_RESPONSE_YES);
           g_signal_connect (dialog, "response", G_CALLBACK (warn_response), NULL);
-          g_object_set_data (inspector_window, "warning_dialog", dialog);
+          g_object_set_data (G_OBJECT (inspector_window), "warning_dialog", dialog);
         }
     }
 
-  dialog = g_object_get_data (inspector_window, "warning_dialog");
+  dialog = g_object_get_data (G_OBJECT (inspector_window), "warning_dialog");
 
   if (enable)
     {