Fix crash when intersecting with NULL region.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@42874 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

diff --git a/src/gtk/dcclient.cpp b/src/gtk/dcclient.cpp
index fc66d7acdd2d7f1781c21f4b37df0cc669d1d7de..77ed883565f1571ac859aac074e45af788dd08e4 100644 (file)
--- a/src/gtk/dcclient.cpp
+++ b/src/gtk/dcclient.cpp
@@ -1319,7 +1319,8 @@ bool wxWindowDC::DoBlit( wxCoord xdest, wxCoord ydest,
             // a clipped bitmap and therefore needs to move the origin
             // accordingly
             wxRegion tmp( xx,yy,ww,hh );
             // a clipped bitmap and therefore needs to move the origin
             // accordingly
             wxRegion tmp( xx,yy,ww,hh );

-            tmp.Intersect( m_currentClippingRegion );
+            if (!m_currentClippingRegion.IsNull())
+                tmp.Intersect( m_currentClippingRegion );

             tmp.GetBox(cx,cy,cw,ch);
 
             // Scale and clipped bitmap
             tmp.GetBox(cx,cy,cw,ch);
 
             // Scale and clipped bitmap