diff --git a/composite/compalloc.c b/composite/compalloc.c
index 0372b9b..7c6cc18 100644
--- a/composite/compalloc.c
+++ b/composite/compalloc.c
@@ -467,6 +467,8 @@ compNewPixmap (WindowPtr pWin, int x, int y, int w, int h)
 
     if (!pPixmap)
 	return 0;
+		if (!pParent)
+			return 0;
     
     pPixmap->screen_x = x;
     pPixmap->screen_y = y;