(gdb) bt full
0  0x08149d02 in RegionNil (reg=<optimized out>)
   at /var/tmp/portage/x11-base/xorg-server-1.12.4/work/xorg-server-1.12.4/include/regionstr.h:74
No locals.
1  RegionNotEmpty (_pReg=<optimized out>)
   at /var/tmp/portage/x11-base/xorg-server-1.12.4/work/xorg-server-1.12.4/include/regionstr.h:178
No locals.
2  damageRegionAppend (pDrawable=0x92f3520, pRegion=0xfffeaa54, clip=0, subWindowMode=-1)
   at /var/tmp/portage/x11-base/xorg-server-1.12.4/work/xorg-server-1.12.4/miext/damage/damage.c:196
       pScreen = <optimized out>
       pScrPriv = 0x8fefd88
       pDamage = 0x0
       pNext = <optimized out>
       clippedRec = {extents = {x1 = 1, y1 = 0, x2 = -18901, y2 = -2322}, data = 0x81f9ff4}
       pDamageRegion = <optimized out>
       pixClip = {extents = {x1 = 0, y1 = 0, x2 = -29814, y2 = 2057}, data = 0x81f9ff4}
       draw_x = <optimized out>
       draw_y = <optimized out>
       screen_x = 0
       screen_y = 0
3  0xf71dfe03 in glamor_composite_rectangles (op=3 '\003', dst=0x927fa98, color=0x91f37ac, num_rects=4, rects=0x91f37b4)
   at /var/tmp/portage/x11-libs/glamor-0.5/work/glamor-0.5/src/glamor_compositerects.c:270
       pixmap = <optimized out>
       priv = 0x0
       region = {extents = {x1 = 1056, y1 = -2225, x2 = -21896, y2 = -2}, data = 0x1}
       boxes = <optimized out>
       dst_x = 135505420
       dst_y = -146940883
       num_boxes = <optimized out>
       source = <optimized out>
       need_free_region = <optimized out>
4  0x0813da52 in CompositeRects (op=3 '\003', pDst=0x927fa98, color=0x91f37ac, nRect=4, rects=0x91f37b4)
   at /var/tmp/portage/x11-base/xorg-server-1.12.4/work/xorg-server-1.12.4/render/picture.c:1593
       ps = <optimized out>
5  0x08140958 in ProcRenderFillRectangles (client=0x91cbae8)
   at /var/tmp/portage/x11-base/xorg-server-1.12.4/work/xorg-server-1.12.4/render/render.c:1426
       pDst = 0x927fa98
       things = <optimized out>
       stuff = 0x91f37a0
6  0x0813e113 in ProcRenderDispatch (client=0x91cbae8)
   at /var/tmp/portage/x11-base/xorg-server-1.12.4/work/xorg-server-1.12.4/render/render.c:1988
       stuff = <optimized out>
7  0x08077f65 in Dispatch () at /var/tmp/portage/x11-base/xorg-server-1.12.4/work/xorg-server-1.12.4/dix/dispatch.c:428
       clientReady = 0x9186910
       result = <optimized out>
       client = 0x91cbae8
       nready = 0
       icheck = 0x82060b8
       start_tick = 120
8  0x08065d7a in main (argc=4, argv=0xfffeaca4, envp=0xfffeacb8)
   at /var/tmp/portage/x11-base/xorg-server-1.12.4/work/xorg-server-1.12.4/dix/main.c:288
       i = <optimized out>
       alwaysCheckForInput = {0, 1}