.
Thread 1 (LWP 1):
#0  conf_file_serialise (file=file@entry=0x7f11929f2440) at conf.c:1633
        json = 0x7f1192f18ed0
        json_job_class = <optimized out>
        registered = <optimized out>
        session_index = <optimized out>
        conf_source_index = <optimized out>
        __FUNCTION__ = "conf_file_serialise"
#1  0x00007f1191eb9b09 in conf_source_serialise (source=source@entry=0x7f11929ef7f0) at conf.c:1377
        file = 0x7f11929f2440
        json_conf_file = <optimized out>
        file_iter = 0x7f11929f2440
        _file_iter_i = 9
        json = 0x7f1192efa950
        json_files = 0x7f1192efac10
        session_index = <optimized out>
        __FUNCTION__ = "conf_source_serialise"
#2  0x00007f1191eb9b76 in conf_source_serialise_all () at conf.c:1416
        json_source = <optimized out>
        source = 0x7f11929ef7f0
        iter = 0x7f11929ef7f0
        json = 0x7f1192efa170
#3  0x00007f1191e9f332 in state_to_string (json_string=json_string@entry=0x7fff6f682e20, len=len@entry=0x7fff6f682e28) at state.c:388
        json = 0x7f1192ae7510
        json_job_environ = <optimized out>
        value = <optimized out>
        __FUNCTION__ = "state_to_string"
#4  0x00007f1191ea1f66 in stateful_reexec () at state.c:1986
        fds = {-1, -1}
        pid = <optimized out>
        mask = {__val = {18446744067267100671, 18446744073709551615 <repeats 15 times>}}
        oldmask = {__val = {0, 139713439369138, 1, 139713452342864, 139713451059056, 5, 140735062486592, 139713439309880, 0, 0, 0, 139713439369138, 140735062486937, 139713452342864, 140735062486920, 139713452342864}}
        state_data = 0x0
        len = 139713441506832
#5  0x00007f1191ebb2f3 in control_restart (data=<optimized out>, message=message@entry=0x7f1192b27e50) at control.c:1209
        session = <optimized out>
        __FUNCTION__ = "control_restart"
#6  0x00007f1191ebecbd in control_com_ubuntu_Upstart0_6_Restart_method (object=0x7f1192aaa1a0, message=0x7f1192b27e50) at com.ubuntu.Upstart.c:718
        iter = {dummy1 = 0x7f1192b0eb10, dummy2 = 0x7f1100600000, dummy3 = 2459944556, dummy4 = 32529, dummy5 = -1853575888, dummy6 = 32529, dummy7 = 0, dummy8 = 32529, dummy9 = -1833899168, dummy10 = 32529, dummy11 = 0, pad1 = 32529, pad2 = -1853575936, pad3 = 0x7f1191a66ad3 <nih_error_push_context+51>}
        reply = <optimized out>
        __FUNCTION__ = "control_com_ubuntu_Upstart0_6_Restart_method"
#7  0x00007f1191850152 in nih_dbus_object_message (connection=0x7f1192aa58c0, message=0x7f1192b0eb10, object=0x7f1192aaa1a0) at dbus_object.c:267
        msg = 0x7f1192b27e50
        result = <optimized out>
        method = 0x7f11920d08a0 <control_com_ubuntu_Upstart0_6_methods+96>
        interface = 0x7f11920d2610 <control_interfaces>
        __FUNCTION__ = "nih_dbus_object_message"
#8  0x00007f1191622e36 in ?? () from /tmp/apport_sandbox_0PW1UB/lib/x86_64-linux-gnu/libdbus-1.so.3
No symbol table info available.
#9  0x00007f1191615a01 in dbus_connection_dispatch () from /tmp/apport_sandbox_0PW1UB/lib/x86_64-linux-gnu/libdbus-1.so.3
No symbol table info available.
#10 0x00007f119184f418 in nih_dbus_callback (connection=0x7f1192aa58c0, loop=<optimized out>) at dbus_connection.c:696
No locals.
#11 0x00007f1191a632aa in nih_main_loop () at main.c:609
        func = <optimized out>
        _iter = {prev = 0x7f1192ace020, next = 0x7f1192afbd00}
        iter = <optimized out>
        timeout = {tv_sec = 4, tv_usec = 999989}
        readfds = {fds_bits = {1024, 0 <repeats 15 times>}}
        writefds = {fds_bits = {0 <repeats 16 times>}}
        buf = ""
        ret = <optimized out>
        next_timer = <optimized out>
        now = {tv_sec = 45, tv_nsec = 495730057}
        exceptfds = {fds_bits = {0 <repeats 16 times>}}
        nfds = 37
        __FUNCTION__ = "nih_main_loop"
#12 0x00007f1191e9c5a0 in main (argc=<optimized out>, argv=<optimized out>) at main.c:804
        args = <optimized out>
        ret = <optimized out>
        enforce = 0
        __FUNCTION__ = "main"