Description of problem:
$ gdb gtk3-demo
(gdb) r
Starting program: /usr/bin/gtk3-demo 
[Thread debugging using libthread_db enabled]

** (gtk3-demo:27642): WARNING **: AT-SPI: Accessibility bus not found - Using session bus.

[New Thread 0x7fffea42e700 (LWP 27646)]

Program received signal SIGSEGV, Segmentation fault.
g_list_length (list=0x656c67676f740065 = {...}) at glist.c:907
907	      list = list->next;

(gdb) bt
#0  g_list_length (list=0x656c67676f740065 = {...}) at glist.c:907
#1  0x00007ffff78591ad in gtk_assistant_accessible_get_n_children (accessible=
    0x855d30 [GtkAssistantAccessible]) at gtkassistant.c:2530
#2  0x00007fffeb001d20 in append_children (traversal=0x696d20, accessible=
    0x855d30 [GtkAssistantAccessible])
    at ../../atk-adaptor/accessible-cache.c:225
#3  add_pending_items (data=<optimized out>)
    at ../../atk-adaptor/accessible-cache.c:280
#4  0x00007ffff3d27a9d in g_main_dispatch (context=0x661bd0) at gmain.c:2440
#5  g_main_context_dispatch (context=0x661bd0) at gmain.c:3013
#6  0x00007ffff3d28278 in g_main_context_iterate (context=0x661bd0, 
    block=<optimized out>, dispatch=1, self=<optimized out>) at gmain.c:3091
#7  0x00007ffff3d288ba in g_main_loop_run (loop=0x842b70) at gmain.c:3299
#8  0x00007ffff79211ed in gtk_main () at gtkmain.c:1349
#9  0x00000000004107c7 in main (argc=1, argv=0x7fffffffe1b8) at main.c:1009


Version-Release number of selected component (if applicable):
3.0.0-1.fc15.x86_64

How reproducible:
always

Steps to Reproduce:
1. lanuch gtk3-demo
2. Click Assistant
3.
  
Actual results:


Expected results:


Additional info:
glib2-2.28.0-2.fc15.x86_64