Wed Mar 10 18:13:52 CET 2010  Tobias Rautenkranz <tobias@rautenkranz.ch>
  * Delete QPainDevices before the QApplication is destroyed.
Mon Jan 25 20:09:40 CET 2010  Tobias Rautenkranz <tobias@rautenkranz.ch>
  * Fix with-app cleanup
diff -rN -u old-qt.gui/src/application.lisp new-qt.gui/src/application.lisp
--- old-qt.gui/src/application.lisp	2014-11-24 13:47:07.000000000 +0100
+++ new-qt.gui/src/application.lisp	2014-11-24 13:47:07.000000000 +0100
@@ -2,7 +2,7 @@
 
 (defvar *widgets* nil)
 
-(defmethod delete-app :around ((application qt:application))
+(defmethod cl-smoke.qt.core:delete-app :around ((application qt:application))
   (qt:application.close-all-windows)
   ;; widgets are only valid as long, as an application object
   ;; exists.  QApplication::~QApplication() deletes all widgets in
@@ -11,6 +11,13 @@
   ;; see: qt4/src/gui/kernel/qapplication.cpp
   (loop for widget across (qt:application.all-widgets) do
        (tg:cancel-finalization widget))
+  ;; QPaintDevices are only valid when a application object exists.
+  (loop for object being the hash-values of smoke::*object-map* do
+       (when (typep object 'qt:paint-device)
+         (delete-object object)))
+  ;; Finalize other stuff before deleting the QApplication,
+  ;; e.g. QGraphicsScene
+  (tg:gc :full t)
   (call-next-method)
   (setf *widgets* nil))