Comment 6 for bug 721777

here is the proper stack trace, with G_DEBUG=fatal_criticals:

GLib-GObject-CRITICAL **: g_object_unref: assertion `G_IS_OBJECT (object)' failed
aborting...

Program received signal SIGABRT, Aborted.
0x0012e416 in __kernel_vsyscall ()
------------------------------------------------
(gdb) bt
#0 0x0012e416 in __kernel_vsyscall ()
#1 0x00298e61 in raise (sig=6) at ../nptl/sysdeps/unix/sysv/linux/raise.c:64
#2 0x0029c33e in abort () at abort.c:92
#3 0x001c7077 in g_logv (log_domain=0x17178c "GLib-GObject", log_level=<value optimized out>, format=0x2108a0 "%s: assertion `%s' failed", args1=0xbffff46c "\"<\027") at /build/buildd/glib2.0-2.28.0/glib/gmessages.c:557
#4 0x001c70b2 in g_log (log_domain=0x17178c "GLib-GObject", log_level=G_LOG_LEVEL_CRITICAL, format=0x2108a0 "%s: assertion `%s' failed") at /build/buildd/glib2.0-2.28.0/glib/gmessages.c:577
#5 0x001c72dd in g_return_if_fail_warning (log_domain=0x17178c "GLib-GObject", pretty_function=0x173c22 "g_object_unref", expression=0x172df6 "G_IS_OBJECT (object)") at /build/buildd/glib2.0-2.28.0/glib/gmessages.c:586
#6 0x00143802 in g_object_unref (_object=0x0) at /build/buildd/glib2.0-2.28.0/gobject/gobject.c:2669
#7 0x0049fad3 in g_dbus_proxy_finalize (object=0x8056408) at /build/buildd/glib2.0-2.28.0/gio/gdbusproxy.c:159
#8 0x0014396c in g_object_unref (_object=0x8056408) at /build/buildd/glib2.0-2.28.0/gobject/gobject.c:2734
#9 0x00436292 in g_initable_new_valist (object_type=134563680, first_property_name=0x4e3932 "g-flags", var_args=0xbffff5a0 "\001", cancellable=0x0, error=0x0) at /build/buildd/glib2.0-2.28.0/gio/ginitable.c:221
#10 0x004362d9 in g_initable_new (object_type=134563680, cancellable=0x0, error=0x0, first_property_name=0x4e3932 "g-flags") at /build/buildd/glib2.0-2.28.0/gio/ginitable.c:139
#11 0x004a1230 in g_dbus_proxy_new_for_bus_sync (bus_type=G_BUS_TYPE_SESSION, flags=G_DBUS_PROXY_FLAGS_DO_NOT_LOAD_PROPERTIES, info=0x0, name=0x13334d "org.freedesktop.Notifications", object_path=0x1333dc "/org/freedesktop/Notifications", interface_name=0x13334d "org.freedesktop.Notifications", cancellable=0x0, error=0x0) at /build/buildd/glib2.0-2.28.0/gio/gdbusproxy.c:1881
#12 0x00130f66 in _notify_get_proxy (error=0x0) at notify.c:229
#13 0x001320d3 in notify_notification_show (notification=0x8052290, error=0x0) at notification.c:518
#14 0x080493d1 in main (argc=1, argv=0xbffff854) at notify-send.c:269