Bug#269306: Steps to reproduce

[André Dahlqvist]

I have repeatedly seen what I believe is the same crash as this since 
the very first 2.6.x release. It often happens on logout for me, and I 
believe I know the reason for that; before I log out I usually check 
that I have closed down all windows by clicking on the Window Selector 
applet. So the crash seams to be related to using Window Selector when 
there are no open windows.

I have found a reproducable way to get wnck-applet to crash and I 
believe that the cause of the crash is the same as this bug.

Steps to reproduce:

1) Make sure no applications are open, so there are no windows in Window 
Selector.
2) Repeatedly click on Window Selector so that the (empty) list is shown 
and then hidden. Try it about 5 times or more. After several times 
wnck-applet should crash. If it doesn't, try hiding the list, wait a few 
seconds and then try again with the repeated showing/hiding procedure.

For me, these steps causes a crash in wnck-applet every time. The gnome 
bug reporting tool comes up, but unfortunately it doesn't get a strack 
trace of the crash. To get a strack trace I have tried running "gdb 
--pid" on the wnck-applet process and this is the trace I get:

#0  0x402c640e in __waitpid_nocancel () from /lib/tls/libpthread.so.0
#1  0x400e7f48 in libgnomeui_module_info_get () from 
/usr/lib/libgnomeui-2.so.0
#2  <signal handler called>
#3  0x4076c3af in g_type_check_instance_is_a ()
    from /usr/lib/libgobject-2.0.so.0
#4  0x4075470a in g_object_unref () from /usr/lib/libgobject-2.0.so.0
#5  0x0804f443 in main ()

That stack doesn't really seam to point directly to wnck-applet, does 
it? Anyway, the steps above should help people reproduce the crash.