Work around <https://bugs.freedesktop.org/show_bug.cgi?id=92027>.

--- pixman-0.32.6/pixman/pixman-general.c	2015-09-16 21:44:40.793222811 +0200
+++ pixman-0.32.6/pixman/pixman-general.c	2015-09-16 21:44:51.961331052 +0200
@@ -157,7 +157,6 @@ general_composite_rect  (pixman_implemen
 	dest_buffer = ALIGN (mask_buffer + width * Bpp);
     }
 
-    if (width_flag == ITER_WIDE)
     {
 	/* To make sure there aren't any NANs in the buffers */
 	memset (src_buffer, 0, width * Bpp);