Index: /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UIMachineView.cpp
===================================================================
--- /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UIMachineView.cpp	(revision 46537)
+++ /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UIMachineView.cpp	(revision 46538)
@@ -218,6 +218,6 @@
      * when entering or exiting fullscreen on X.Org guests and when
      * re-attaching the frame-buffer on a view switch. */
-    bool fResize =    iWidth != frameBuffer()->width()
-                   || iHeight != frameBuffer()->height();
+    bool fResize =    (ulong)iWidth != frameBuffer()->width()
+                   || (ulong)iHeight != frameBuffer()->height();
 
     /* If machine-window is visible: */