Comment 2 for bug 907802

tried debugging gnome-session. It seems the problem is assertion in GLib-GIO, not the gnome-session itself:
GLib-GIO:ERROR:/build/buildd/glib2.0-2.30.0/./gio/gsettingsschema.c:125:ensure_schema_lists: assertion failed: (list != NULL)

(gdb) r
Starting program: /usr/bin/gnome-session
[Thread debugging using libthread_db enabled]
[New Thread 0x7fffed9d2700 (LWP 25084)]
[New Thread 0x7fffed1d1700 (LWP 25086)]
[New Thread 0x7fffec9d0700 (LWP 25087)]
**
GLib-GIO:ERROR:/build/buildd/glib2.0-2.30.0/./gio/gsettingsschema.c:125:ensure_schema_lists: assertion failed: (list != NULL)

Program received signal SIGABRT, Aborted.
0x00007ffff47d63a5 in __GI_raise (sig=6) at ../nptl/sysdeps/unix/sysv/linux/raise.c:64
64 ../nptl/sysdeps/unix/sysv/linux/raise.c: No such file or directory.
 in ../nptl/sysdeps/unix/sysv/linux/raise.c
(gdb) bt
#0 0x00007ffff47d63a5 in __GI_raise (sig=6) at ../nptl/sysdeps/unix/sysv/linux/raise.c:64
#1 0x00007ffff47d9b0b in __GI_abort () at abort.c:92
#2 0x00007ffff4ba74ad in g_assertion_message () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3 0x00007ffff4ba79d2 in g_assertion_message_expr () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#4 0x00007ffff534e17d in ?? () from /usr/lib/x86_64-linux-gnu/libgio-2.0.so.0
#5 0x00007ffff534e279 in g_settings_list_schemas () from /usr/lib/x86_64-linux-gnu/libgio-2.0.so.0
#6 0x000000000040e3f7 in setup_gsettings_condition_monitor (key=<optimized out>, app=0x713010) at gsm-autostart-app.c:352
#7 setup_condition_monitor (app=0x713010) at gsm-autostart-app.c:547
#8 load_desktop_file (app=0x713010) at gsm-autostart-app.c:660
#9 gsm_autostart_app_constructor (type=<optimized out>, n_construct_properties=<optimized out>, construct_properties=<optimized out>) at gsm-autostart-app.c:1406
#10 0x00007ffff5077e94 in g_object_newv () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#11 0x00007ffff5078d66 in g_object_new_valist () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#12 0x00007ffff5079074 in g_object_new () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#13 0x000000000040ef5d in gsm_autostart_app_new (desktop_file=0x70b3d0 "/usr/share/gnome/autostart/libcanberra-login-sound.desktop") at gsm-autostart-app.c:1464
#14 0x0000000000420058 in add_autostart_app_internal (manager=0x6f30a0, path=0x70b3d0 "/usr/share/gnome/autostart/libcanberra-login-sound.desktop", provides=0x0, is_required=0) at gsm-manager.c:4003
#15 0x0000000000423260 in gsm_manager_add_autostart_apps_from_dir (manager=0x6f30a0, path=0x7066b0 "/usr/share/gnome/autostart") at gsm-manager.c:4111
#16 0x0000000000423f84 in load_standard_apps (keyfile=0x6f04f0, manager=0x6f30a0) at gsm-session-fill.c:238
#17 gsm_session_fill (manager=0x6f30a0, override_autostart_dirs=<optimized out>, session=<optimized out>) at gsm-session-fill.c:499
#18 0x000000000040b6ff in main (argc=1, argv=0x7fffffffe328) at main.c:357