[compiz] gtk-window-decorator segfault

[David Reveman]

On Wed, 2007-02-14 at 20:38 +0100, gandalfn wrote:
> I have same issue and after apply latest commit, gtk-window-decorator
> now hangs. When i attach with gdb, i have this backtrace :
> 
> #0  0xb7f27410 in __kernel_vsyscall ()
> #1  0xb75ae6bb in poll () from /lib/tls/i686/cmov/libc.so.6
> #2  0xb773ef19 in _XWaitForReadable (dpy=0x806d300)
> at ../../src/XlibInt.c:500
> #3  0xb773f2ff in _XRead (dpy=0x806d300, data=0xbfa4531c "\034\033[\234
> ", 
>     size=32) at ../../src/XlibInt.c:1089
> #4  0xb773fcd4 in _XReply (dpy=0x806d300, rep=0xbfa4531c, extra=0,
> discard=0)
>     at ../../src/XlibInt.c:1716
> #5  0xb7721176 in XGetWindowProperty (dpy=0x806d300, w=93,
> property=351, 
>     offset=0, length=2147483647, delete=0, req_type=33, 
>     actual_type=0xbfa453a8, actual_format=0xbfa453a4,
> nitems=0xbfa453a0, 
>     bytesafter=0xbfa4539c, prop=0xbfa45398) at ../../src/GetProp.c:64
> #6  0xb7efd163 in _wnck_get_window_list (xwindow=93, atom=351, 
>     windows=0xbfa454b8, len=0xbfa454b4) at xutils.c:399
> #7  0xb7ee914c in do_update_now (screen=0x80851c0) at screen.c:1186
> #8  0xb7ee9fc8 in update_idle (data=0x80851c0) at screen.c:1936
> #9  0xb7655ee1 in g_idle_dispatch (source=0x810f570,
> callback=0xffffffff, 
>     user_data=0x80851c0) at gmain.c:3928
> #10 0xb7657c42 in IA__g_main_context_dispatch (context=0x807bb78)
>     at gmain.c:2045
> #11 0xb765ac1f in g_main_context_iterate (context=0x807bb78, block=1, 
>     dispatch=1, self=0x8095dc8) at gmain.c:2677
> #12 0xb765afc9 in IA__g_main_loop_run (loop=0x8109260) at gmain.c:2881
> #13 0xb7b9bf84 in IA__gtk_main () at gtkmain.c:1171
> 
> It's seem gtk-window-decorator hang when libwnck get
> _NET_CLIENT_LIST_STACKING window property.

That's strange, XGetWindowProperty should never be able hang an
application like that unless the server hangs. I suspect that the real
problem occurs before _wnck_get_window_list is called. Is valgrind
reporting anything suspicious?

- David