#0  0x00007f276dd4e178 in __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:54
        resultvar = 0
        pid = 2042
        selftid = 2042
#1  0x00007f276dd4f5fa in __GI_abort () at abort.c:89
        save_stage = 2
        act = {__sigaction_handler = {sa_handler = 0x4, sa_sigaction = 0x4}, sa_mask = {__val = {0, 7598805615236638051, 140720333155408, 38654705664, 0, 0, 0, 
              21474836480, 139807324352512, 140720333155560, 140720308486145, 139807324366200, 139807324379824, 0, 139807366000640, 6709058}}, sa_flags = 95, 
          sa_restorer = 0x665fd0 <__PRETTY_FUNCTION__.16529>}
        sigs = {__val = {32, 0 <repeats 15 times>}}
#2  0x00007f276dd470b7 in __assert_fail_base (fmt=<optimized out>, assertion=assertion@entry=0x665f42 "flip_pending->abort_flip", 
    file=file@entry=0x665ee8 "/var/tmp/portage/x11-base/xorg-server-9999/work/xorg-server-9999/present/present_screen.c", line=line@entry=95, 
    function=function@entry=0x665fd0 <__PRETTY_FUNCTION__.16529> "present_clear_window_flip") at assert.c:92
        str = 0x1922aa0 "@2\210\001"
        total = 4096
#3  0x00007f276dd47162 in __GI___assert_fail (assertion=0x665f42 "flip_pending->abort_flip", 
    file=0x665ee8 "/var/tmp/portage/x11-base/xorg-server-9999/work/xorg-server-9999/present/present_screen.c", line=95, 
    function=0x665fd0 <__PRETTY_FUNCTION__.16529> "present_clear_window_flip") at assert.c:101
No locals.
#4  0x000000000056fe1e in present_clear_window_flip (window=0x1535640) at /var/tmp/portage/x11-base/xorg-server-9999/work/xorg-server-9999/present/present_screen.c:95
        screen = 0x13d84b0
        screen_priv = 0x13eeb30
        flip_pending = 0x1945330
        __PRETTY_FUNCTION__ = "present_clear_window_flip"
#5  0x000000000056feb6 in present_destroy_window (window=0x1535640) at /var/tmp/portage/x11-base/xorg-server-9999/work/xorg-server-9999/present/present_screen.c:117
        ret = 32764
        screen = 0x13d84b0
        screen_priv = 0x13eeb30
        window_priv = 0x1921610
#6  0x000000000050101c in compDestroyWindow (pWin=0x1535640) at /var/tmp/portage/x11-base/xorg-server-9999/work/xorg-server-9999/composite/compwindow.c:609
        pScreen = 0x13d84b0
        cs = 0x13efbf0
        cw = 0x0
        csw = 0x0
        ret = 32764
#7  0x000000000047b13f in FreeWindowResources (pWin=0x1535640) at /var/tmp/portage/x11-base/xorg-server-9999/work/xorg-server-9999/dix/window.c:1031
        pScreen = 0x13d84b0
#8  0x000000000047b49d in DeleteWindow (value=0x1535640, wid=213) at /var/tmp/portage/x11-base/xorg-server-9999/work/xorg-server-9999/dix/window.c:1099
        pParent = 0x0
        pWin = 0x1535640
#9  0x000000000046da34 in doFreeResource (res=0x13efd50, skip=0) at /var/tmp/portage/x11-base/xorg-server-9999/work/xorg-server-9999/dix/resource.c:895
No locals.
#10 0x000000000046e444 in FreeClientResources (client=0x13b93f0) at /var/tmp/portage/x11-base/xorg-server-9999/work/xorg-server-9999/dix/resource.c:1161
        head = 0x13b96a0
        resources = 0x13b95f0
        this = 0x13efd50
        j = 22
#11 0x000000000046e533 in FreeAllResources () at /var/tmp/portage/x11-base/xorg-server-9999/work/xorg-server-9999/dix/resource.c:1176
        i = 0
#12 0x000000000043fc80 in dix_main (argc=4, argv=0x7ffc017870e8, envp=0x7ffc01787110) at /var/tmp/portage/x11-base/xorg-server-9999/work/xorg-server-9999/dix/main.c:324
        remember_it = 1
        i = 1
        alwaysCheckForInput = {0, 1}
#13 0x000000000042060e in main (argc=4, argv=0x7ffc017870e8, envp=0x7ffc01787110) at /var/tmp/portage/x11-base/xorg-server-9999/work/xorg-server-9999/dix/stubmain.c:34
No locals.
#0  0x00007f276dd4e178 in __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:54
#1  0x00007f276dd4f5fa in __GI_abort () at abort.c:89
#2  0x00007f276dd470b7 in __assert_fail_base (fmt=<optimized out>, assertion=assertion@entry=0x665f42 "flip_pending->abort_flip", 
    file=file@entry=0x665ee8 "/var/tmp/portage/x11-base/xorg-server-9999/work/xorg-server-9999/present/present_screen.c", line=line@entry=95, 
    function=function@entry=0x665fd0 <__PRETTY_FUNCTION__.16529> "present_clear_window_flip") at assert.c:92
#3  0x00007f276dd47162 in __GI___assert_fail (assertion=0x665f42 "flip_pending->abort_flip", 
    file=0x665ee8 "/var/tmp/portage/x11-base/xorg-server-9999/work/xorg-server-9999/present/present_screen.c", line=95, 
    function=0x665fd0 <__PRETTY_FUNCTION__.16529> "present_clear_window_flip") at assert.c:101
#4  0x000000000056fe1e in present_clear_window_flip (window=0x1535640) at /var/tmp/portage/x11-base/xorg-server-9999/work/xorg-server-9999/present/present_screen.c:95
#5  0x000000000056feb6 in present_destroy_window (window=0x1535640) at /var/tmp/portage/x11-base/xorg-server-9999/work/xorg-server-9999/present/present_screen.c:117
#6  0x000000000050101c in compDestroyWindow (pWin=0x1535640) at /var/tmp/portage/x11-base/xorg-server-9999/work/xorg-server-9999/composite/compwindow.c:609
#7  0x000000000047b13f in FreeWindowResources (pWin=0x1535640) at /var/tmp/portage/x11-base/xorg-server-9999/work/xorg-server-9999/dix/window.c:1031
#8  0x000000000047b49d in DeleteWindow (value=0x1535640, wid=213) at /var/tmp/portage/x11-base/xorg-server-9999/work/xorg-server-9999/dix/window.c:1099
#9  0x000000000046da34 in doFreeResource (res=0x13efd50, skip=0) at /var/tmp/portage/x11-base/xorg-server-9999/work/xorg-server-9999/dix/resource.c:895
#10 0x000000000046e444 in FreeClientResources (client=0x13b93f0) at /var/tmp/portage/x11-base/xorg-server-9999/work/xorg-server-9999/dix/resource.c:1161
#11 0x000000000046e533 in FreeAllResources () at /var/tmp/portage/x11-base/xorg-server-9999/work/xorg-server-9999/dix/resource.c:1176
#12 0x000000000043fc80 in dix_main (argc=4, argv=0x7ffc017870e8, envp=0x7ffc01787110) at /var/tmp/portage/x11-base/xorg-server-9999/work/xorg-server-9999/dix/main.c:324
#13 0x000000000042060e in main (argc=4, argv=0x7ffc017870e8, envp=0x7ffc01787110) at /var/tmp/portage/x11-base/xorg-server-9999/work/xorg-server-9999/dix/stubmain.c:34