gwibber (new theming engine) pango segmentation fault @pango_layout_get_iter

Running latest bzr 321 from lp:gwibber. After a while eventually get a segfault in libpango. (updated):

$ apt-cache policy libpango1.0-0 libgtk2.0-0 libglib2.0-0
libpango1.0-0:
  Installed: 1.24.2-1ubuntu1
libgtk2.0-0:
  Installed: 2.16.1-0ubuntu3
libglib2.0-0:
  Installed: 2.21.0-0ubuntu1

(gdb) bt
#0 pango_layout_get_iter (layout=0xa933f20) at /build/buildd/pango1.0-1.24.2/pango/pango-layout.c:5521
#1 0x00470b94 in pango_renderer_draw_layout (renderer=0x98620b8, layout=0xa933f20, x=3072, y=1108992)
    at /build/buildd/pango1.0-1.24.2/pango/pango-renderer.c:185
#2 0x00debba8 in IA__gdk_draw_layout_with_colors (drawable=0x9355530, gc=0x9cce550, x=3, y=1083, layout=0xa933f20, foreground=0x0,
    background=0x0) at /build/buildd/gtk+2.0-2.16.1/gdk/gdkpango.c:998
#3 0x00debd31 in IA__gdk_draw_layout (drawable=0x9355530, gc=0x9cce550, x=3, y=1083, layout=0xa933f20)
    at /build/buildd/gtk+2.0-2.16.1/gdk/gdkpango.c:1060
#4 0x0095003e in ?? () from /usr/lib/gtk-2.0/2.10.0/engines/libclearlooks.so
#5 0x01177c47 in IA__gtk_paint_layout (style=0x9c19318, window=0x0, state_type=GTK_STATE_NORMAL, use_text=0, area=0x985719c,
    widget=0x9854698, detail=0x132d5ef "label", x=3, y=1083, layout=0xa933f20) at /build/buildd/gtk+2.0-2.16.1/gtk/gtkstyle.c:6588
#6 0x010ed1b6 in gtk_label_expose (widget=0x9854698, event=0x9857190) at /build/buildd/gtk+2.0-2.16.1/gtk/gtklabel.c:2932
#7 0x010fc924 in _gtk_marshal_BOOLEAN__BOXED (closure=0x9358f58, return_value=0xbfcee944, n_param_values=2, param_values=0xb54a5400,
    invocation_hint=0xbfcee930, marshal_data=0x10ed0b0) at /build/buildd/gtk+2.0-2.16.1/gtk/gtkmarshalers.c:84
#8 0x0012a759 in g_type_class_meta_marshal (closure=0x9358f58, return_value=0xbfcee944, n_param_values=2, param_values=0xb54a5400,
    invocation_hint=0xbfcee930, marshal_data=0xc8) at /build/buildd/glib2.0-2.21.0/gobject/gclosure.c:878
#9 0x0012c008 in IA__g_closure_invoke (closure=0x9358f58, return_value=0xbfcee944, n_param_values=2, param_values=0xb54a5400,
    invocation_hint=0xbfcee930) at /build/buildd/glib2.0-2.21.0/gobject/gclosure.c:767
#10 0x0014298b in signal_emit_unlocked_R (node=<value optimized out>, detail=<value optimized out>, instance=0x9854698,
    emission_return=0xbfceea8c, instance_and_params=0xb54a5400) at /build/buildd/glib2.0-2.21.0/gobject/gsignal.c:3285
#11 0x00143f70 in IA__g_signal_emit_valist (instance=0x9854698, signal_id=38, detail=0, var_args=0xbfceeaf0 ",\ufffd\u03bf\ufffd2\ufffd")
    at /build/buildd/glib2.0-2.21.0/gobject/gsignal.c:2990
#12 0x00144566 in IA__g_signal_emit (instance=0x9854698, signal_id=38, detail=0) at /build/buildd/glib2.0-2.21.0/gobject/gsignal.c:3037
#13 0x01217ede in gtk_widget_event_internal (widget=<value optimized out>, event=0x9857190)
    at /build/buildd/gtk+2.0-2.16.1/gtk/gtkwidget.c:4761
#14 0x0106cd93 in IA__gtk_container_propagate_expose (container=0x98b7c20, child=0x9854698, event=0x9857230)
    at /build/buildd/gtk+2.0-2.16.1/gtk/gtkcontainer.c:2731
#15 0x0106cdc1 in gtk_container_expose_child (child=0x9854698, client_data=0xbfceec28) at /build/buildd/gtk+2.0-2.16.1/gtk/gtkcontainer.c:2619
#16 0x010b7d68 in gtk_frame_forall (container=0x98b7c20, include_internals=1, callback=0x106cda0 <gtk_container_expose_child>,
    callback_data=0xbfceec28) at /build/buildd/gtk+2.0-2.16.1/gtk/gtkframe.c:300
#17 0x0106d938 in IA__gtk_container_forall (container=0x98b7c20, callback=0x106cda0 <gtk_container_expose_child>, callback_data=0xbfceec28)
    at /build/buildd/gtk+2.0-2.16.1/gtk/gtkcontainer.c:1499
#18 0x0106ec42 in gtk_container_expose (widget=0x98b7c20, event=0x9857230) at /build/buildd/gtk+2.0-2.16.1/gtk/gtkcontainer.c:2642
#19 0x010b8eb7 in gtk_frame_expose (widget=0x98b7c20, event=0x9857230) at /build/buildd/gtk+2.0-2.16.1/gtk/gtkframe.c:595
#20 0x010fc924 in _gtk_marshal_BOOLEAN__BOXED (closure=0x9358f58, return_value=0xbfceee94, n_param_values=2, param_values=0xa200368,
    invocation_hint=0xbfceee80, marshal_data=0x10b8d10) at /build/buildd/gtk+2.0-2.16.1/gtk/gtkmarshalers.c:84
#21 0x0012a759 in g_type_class_meta_marshal (closure=0x9358f58, return_value=0xbfceee94, n_param_values=2, param_values=0xa200368,
    invocation_hint=0xbfceee80, marshal_data=0xc8) at /build/buildd/glib2.0-2.21.0/gobject/gclosure.c:878
#22 0x0012c008 in IA__g_closure_invoke (closure=0x9358f58, return_value=0xbfceee94, n_param_values=2, param_values=0xa200368,
    invocation_hint=0xbfceee80) at /build/buildd/glib2.0-2.21.0/gobject/gclosure.c:767
#23 0x0014298b in signal_emit_unlocked_R (node=<value optimized out>, detail=<value optimized out>, instance=0x98b7c20,
    emission_return=0xbfceefdc, instance_and_params=0xa200368) at /build/buildd/glib2.0-2.21.0/gobject/gsignal.c:3285
#24 0x00143f70 in IA__g_signal_emit_valist (instance=0x98b7c20, signal_id=38, detail=0, var_args=0xbfcef040 "|\ufffd\u03bf\ufffd2\ufffd")
    at /build/buildd/glib2.0-2.21.0/gobject/gsignal.c:2990
#25 0x00144566 in IA__g_signal_emit (instance=0x98b7c20, signal_id=38, detail=0) at /build/buildd/glib2.0-2.21.0/gobject/gsignal.c:3037
#26 0x01217ede in gtk_widget_event_internal (widget=<value optimized out>, event=0x9857230)
    at /build/buildd/gtk+2.0-2.16.1/gtk/gtkwidget.c:4761
#27 0x0106cd93 in IA__gtk_container_propagate_expose (container=0x9854c10, child=0x98b7c20, event=0x98572d0)
    at /build/buildd/gtk+2.0-2.16.1/gtk/gtkcontainer.c:2731
---Type <return> to continue, or q <return> to quit---
#28 0x0106cdc1 in gtk_container_expose_child (child=0x98b7c20, client_data=0xbfcef188) at /build/buildd/gtk+2.0-2.16.1/gtk/gtkcontainer.c:2619
#29 0x0103a7c8 in gtk_box_forall (container=0x9854c10, include_internals=1, callback=0x106cda0 <gtk_container_expose_child>,
    callback_data=0xbfcef188) at /build/buildd/gtk+2.0-2.16.1/gtk/gtkbox.c:1249
#30 0x0106d938 in IA__gtk_container_forall (container=0x9854c10, callback=0x106cda0 <gtk_container_expose_child>, callback_data=0xbfcef188)
    at /build/buildd/gtk+2.0-2.16.1/gtk/gtkcontainer.c:1499
#31 0x0106ec42 in gtk_container_expose (widget=0x9854c10, event=0x98572d0) at /build/buildd/gtk+2.0-2.16.1/gtk/gtkcontainer.c:2642
#32 0x011721d3 in gtk_statusbar_expose_event (widget=0x9854c10, event=0x98572d0) at /build/buildd/gtk+2.0-2.16.1/gtk/gtkstatusbar.c:772
#33 0x010fc924 in _gtk_marshal_BOOLEAN__BOXED (closure=0x9358f58, return_value=0xbfcef3a4, n_param_values=2, param_values=0x9beb990,
    invocation_hint=0xbfcef390, marshal_data=0x11721a0) at /build/buildd/gtk+2.0-2.16.1/gtk/gtkmarshalers.c:84
#34 0x0012a759 in g_type_class_meta_marshal (closure=0x9358f58, return_value=0xbfcef3a4, n_param_values=2, param_values=0x9beb990,
    invocation_hint=0xbfcef390, marshal_data=0xc8) at /build/buildd/glib2.0-2.21.0/gobject/gclosure.c:878
#35 0x0012c008 in IA__g_closure_invoke (closure=0x9358f58, return_value=0xbfcef3a4, n_param_values=2, param_values=0x9beb990,
    invocation_hint=0xbfcef390) at /build/buildd/glib2.0-2.21.0/gobject/gclosure.c:767
#36 0x0014298b in signal_emit_unlocked_R (node=<value optimized out>, detail=<value optimized out>, instance=0x9854c10,
    emission_return=0xbfcef4ec, instance_and_params=0x9beb990) at /build/buildd/glib2.0-2.21.0/gobject/gsignal.c:3285
#37 0x00143f70 in IA__g_signal_emit_valist (instance=0x9854c10, signal_id=38, detail=0, var_args=0xbfcef550 "\214\ufffd\u03bf\ufffd2\ufffd")
    at /build/buildd/glib2.0-2.21.0/gobject/gsignal.c:2990
#38 0x00144566 in IA__g_signal_emit (instance=0x9854c10, signal_id=38, detail=0) at /build/buildd/glib2.0-2.21.0/gobject/gsignal.c:3037
#39 0x01217ede in gtk_widget_event_internal (widget=<value optimized out>, event=0x98572d0)
    at /build/buildd/gtk+2.0-2.16.1/gtk/gtkwidget.c:4761
#40 0x0106cd93 in IA__gtk_container_propagate_expose (container=0x984b410, child=0x9854c10, event=0x9857280)
    at /build/buildd/gtk+2.0-2.16.1/gtk/gtkcontainer.c:2731
#41 0x0106cdc1 in gtk_container_expose_child (child=0x9854c10, client_data=0xbfcef698) at /build/buildd/gtk+2.0-2.16.1/gtk/gtkcontainer.c:2619
#42 0x0103a7c8 in gtk_box_forall (container=0x984b410, include_internals=1, callback=0x106cda0 <gtk_container_expose_child>,
    callback_data=0xbfcef698) at /build/buildd/gtk+2.0-2.16.1/gtk/gtkbox.c:1249
#43 0x0106d938 in IA__gtk_container_forall (container=0x984b410, callback=0x106cda0 <gtk_container_expose_child>, callback_data=0xbfcef698)
    at /build/buildd/gtk+2.0-2.16.1/gtk/gtkcontainer.c:1499
#44 0x0106ec42 in gtk_container_expose (widget=0x984b410, event=0x9857280) at /build/buildd/gtk+2.0-2.16.1/gtk/gtkcontainer.c:2642
#45 0x010fc924 in _gtk_marshal_BOOLEAN__BOXED (closure=0x9358f58, return_value=0xbfcef854, n_param_values=2, param_values=0x9beb918,
    invocation_hint=0xbfcef840, marshal_data=0x106eb90) at /build/buildd/gtk+2.0-2.16.1/gtk/gtkmarshalers.c:84
#46 0x0012a759 in g_type_class_meta_marshal (closure=0x9358f58, return_value=0xbfcef854, n_param_values=2, param_values=0x9beb918,
    invocation_hint=0xbfcef840, marshal_data=0xc8) at /build/buildd/glib2.0-2.21.0/gobject/gclosure.c:878
#47 0x0012c008 in IA__g_closure_invoke (closure=0x9358f58, return_value=0xbfcef854, n_param_values=2, param_values=0x9beb918,
    invocation_hint=0xbfcef840) at /build/buildd/glib2.0-2.21.0/gobject/gclosure.c:767
#48 0x0014298b in signal_emit_unlocked_R (node=<value optimized out>, detail=<value optimized out>, instance=0x984b410,
    emission_return=0xbfcef99c, instance_and_params=0x9beb918) at /build/buildd/glib2.0-2.21.0/gobject/gsignal.c:3285
#49 0x00143f70 in IA__g_signal_emit_valist (instance=0x984b410, signal_id=38, detail=0, var_args=0xbfcefa00 "<\ufffd\u03bf\ufffd2\ufffd")
    at /build/buildd/glib2.0-2.21.0/gobject/gsignal.c:2990
#50 0x00144566 in IA__g_signal_emit (instance=0x984b410, signal_id=38, detail=0) at /build/buildd/glib2.0-2.21.0/gobject/gsignal.c:3037
#51 0x01217ede in gtk_widget_event_internal (widget=<value optimized out>, event=0x9857280)
    at /build/buildd/gtk+2.0-2.16.1/gtk/gtkwidget.c:4761
#52 0x0106cd93 in IA__gtk_container_propagate_expose (container=0x984a028, child=0x984b410, event=0xbfceffd8)
    at /build/buildd/gtk+2.0-2.16.1/gtk/gtkcontainer.c:2731
#53 0x0106cdc1 in gtk_container_expose_child (child=0x984b410, client_data=0xbfcefb28) at /build/buildd/gtk+2.0-2.16.1/gtk/gtkcontainer.c:2619
#54 0x0103656d in gtk_bin_forall (container=0x984a028, include_internals=1, callback=0x106cda0 <gtk_container_expose_child>,
    callback_data=0xbfcefb28) at /build/buildd/gtk+2.0-2.16.1/gtk/gtkbin.c:128
#55 0x0106d938 in IA__gtk_container_forall (container=0x984a028, callback=0x106cda0 <gtk_container_expose_child>, callback_data=0xbfcefb28)
    at /build/buildd/gtk+2.0-2.16.1/gtk/gtkcontainer.c:1499
---Type <return> to continue, or q <return> to quit---
#56 0x0106ec42 in gtk_container_expose (widget=0x984a028, event=0xbfceffd8) at /build/buildd/gtk+2.0-2.16.1/gtk/gtkcontainer.c:2642
#57 0x012320d1 in gtk_window_expose (widget=0x984a028, event=0xbfceffd8) at /build/buildd/gtk+2.0-2.16.1/gtk/gtkwindow.c:6577
#58 0x010fc924 in _gtk_marshal_BOOLEAN__BOXED (closure=0x9358f58, return_value=0xbfcefd34, n_param_values=2, param_values=0x9becf40,
    invocation_hint=0xbfcefd20, marshal_data=0x1232090) at /build/buildd/gtk+2.0-2.16.1/gtk/gtkmarshalers.c:84
#59 0x0012a759 in g_type_class_meta_marshal (closure=0x9358f58, return_value=0xbfcefd34, n_param_values=2, param_values=0x9becf40,
    invocation_hint=0xbfcefd20, marshal_data=0xc8) at /build/buildd/glib2.0-2.21.0/gobject/gclosure.c:878
#60 0x0012c0e2 in IA__g_closure_invoke (closure=0x9358f58, return_value=0xbfcefd34, n_param_values=2, param_values=0x9becf40,
    invocation_hint=0xbfcefd20) at /build/buildd/glib2.0-2.21.0/gobject/gclosure.c:767
#61 0x0014298b in signal_emit_unlocked_R (node=<value optimized out>, detail=<value optimized out>, instance=0x984a028,
    emission_return=0xbfcefe7c, instance_and_params=0x9becf40) at /build/buildd/glib2.0-2.21.0/gobject/gsignal.c:3285
#62 0x00143f70 in IA__g_signal_emit_valist (instance=0x984a028, signal_id=38, detail=0, var_args=0xbfcefee0 "\034\ufffd\u03bfz\001")
    at /build/buildd/glib2.0-2.21.0/gobject/gsignal.c:2990
#63 0x00144566 in IA__g_signal_emit (instance=0x984a028, signal_id=38, detail=0) at /build/buildd/glib2.0-2.21.0/gobject/gsignal.c:3037
#64 0x01217ede in gtk_widget_event_internal (widget=<value optimized out>, event=0xbfceffd8)
    at /build/buildd/gtk+2.0-2.16.1/gtk/gtkwidget.c:4761
#65 0x010f6958 in IA__gtk_main_do_event (event=0xbfceffd8) at /build/buildd/gtk+2.0-2.16.1/gtk/gtkmain.c:1558
#66 0x00dfc441 in gdk_window_process_updates_internal (window=0x9355530) at /build/buildd/gtk+2.0-2.16.1/gdk/gdkwindow.c:2611
#67 0x00dfca3f in IA__gdk_window_process_all_updates () at /build/buildd/gtk+2.0-2.16.1/gdk/gdkwindow.c:2677
#68 0x0106dacf in gtk_container_idle_sizer (data=0x0) at /build/buildd/gtk+2.0-2.16.1/gtk/gtkcontainer.c:1353
#69 0x00de08f8 in gdk_threads_dispatch (data=0x9bf3200) at /build/buildd/gtk+2.0-2.16.1/gdk/gdk.c:498
#70 0x008b30c1 in g_idle_dispatch (source=0xb5412ff0, callback=0xaaaaaaaa, user_data=0x9bf3200)
    at /build/buildd/glib2.0-2.21.0/glib/gmain.c:3922
#71 0x008b4f68 in IA__g_main_context_dispatch (context=0x9357618) at /build/buildd/glib2.0-2.21.0/glib/gmain.c:1814
#72 0x008b8578 in g_main_context_iterate (context=0x9357618, block=<value optimized out>, dispatch=1, self=0x9342138)
    at /build/buildd/glib2.0-2.21.0/glib/gmain.c:2448
#73 0x008b8a2f in IA__g_main_loop_run (loop=0x9d55088) at /build/buildd/glib2.0-2.21.0/glib/gmain.c:2656
#74 0x010f6be9 in IA__gtk_main () at /build/buildd/gtk+2.0-2.16.1/gtk/gtkmain.c:1205
#75 0x00b4833c in ?? () from /usr/lib/pymodules/python2.6/gtk-2.0/gtk/_gtk.so
#76 0x080de7dc in PyEval_EvalFrameEx (f=0x915ce94, throwflag=0) at ../Python/ceval.c:3690
#77 0x080e00b8 in PyEval_EvalCodeEx (co=0xb7f64770, globals=0xb7f5a0b4, locals=0xb7f5a0b4, args=0x0, argcount=0, kws=0x0, kwcount=0,
    defs=0x0, defcount=0, closure=0x0) at ../Python/ceval.c:2968
#78 0x080e0217 in PyEval_EvalCode (co=0xb7f64770, globals=0xb7f5a0b4, locals=0xb7f5a0b4) at ../Python/ceval.c:522
#79 0x080fe0e1 in PyRun_FileExFlags (fp=0x9107cc0, filename=0xbfcf1c89 "bin/gwibber", start=257, globals=0xb7f5a0b4, locals=0xb7f5a0b4,
    closeit=1, flags=0xbfcf07a8) at ../Python/pythonrun.c:1335
#80 0x080fe43a in PyRun_SimpleFileExFlags (fp=0x9107cc0, filename=0xbfcf1c89 "bin/gwibber", closeit=1, flags=0xbfcf07a8)
    at ../Python/pythonrun.c:931
#81 0x0805c882 in Py_Main (argc=1, argv=0xbfcf0874) at ../Modules/main.c:599
#82 0x0805b972 in main (argc=Cannot access memory at address 0x0
) at ../Modules/python.c:23