Description: Do not harness backing store by default
 xorg-server 1.15 enables backing store if composite extension is enabled
 (default settings). Harnessing backing store through compositor leads to
 tearing effect.
 This patch reverts default harnessing backing store to conditional use if
 SDL_VIDEO_X11_BACKINGSTORE environment variable exists.
Origin: https://bugs.launchpad.net/ubuntu/+source/libsdl1.2/+bug/1280665/comments/1
Bug: https://bugzilla.libsdl.org/show_bug.cgi?id=2383
Bug-Debian: https://bugs.debian.org/747168

--- a/src/video/x11/SDL_x11video.c
+++ b/src/video/x11/SDL_x11video.c
@@ -1088,10 +1088,8 @@
 		}
 	}
 
-#if 0 /* This is an experiment - are the graphics faster now? - nope. */
 	if ( SDL_getenv("SDL_VIDEO_X11_BACKINGSTORE") )
-#endif
-	/* Cache the window in the server, when possible */
+	/* Cache the window in the server when possible, on request */
 	{
 		Screen *xscreen;
 		XSetWindowAttributes a;