Comment 6 for bug 1425362

Full stacktrace, including u8 symbols (missing in the automatic retrace).

Unity seems fine actually, but crash happens when calling pam_authenticate where the pamHandle is something like:

{authtok = 0x7fb300000000 <error: Cannot access memory at address 0x7fb300000000>,
  caller_is = 3944807584, pam_conversation = 0xffffffff, oldauthtok = 0x0, prompt = 0x0,
  service_name = 0x0, user = 0x0, rhost = 0x0,
  ruser = 0xffffffff <error: Cannot access memory at address 0xffffffff>, tty = 0x0,
  xdisplay = 0x0, authtok_type = 0x0, data = 0x0, env = 0x0, fail_delay = {set = PAM_FALSE,
    delay = 0, begin = 0, delay_fn_ptr = 0x0}, xauth = {namelen = 0,
    name = 0xffffffffffffffff <error: Cannot access memory at address 0xffffffffffffffff>,
    datalen = 36901392,
    data = 0xffffffff00000001 <error: Cannot access memory at address 0xffffffff00000001>},
  handlers = {module = 0x232d370, modules_allocated = 36855568, modules_used = 0,
    handlers_loaded = 36898784, conf = {authenticate = 0x0, setcred = 0x21,
      acct_mgmt = 0x6d6f6e675f6d6170, open_session = 0x6e697279656b5f65,
      close_session = 0x7f006f730067, chauthtok = 0x21}, other = {
      authenticate = 0x6c61776b5f6d6170, setcred = 0x6f730074656c, acct_mgmt = 0x0,
      open_session = 0xd1, close_session = 0x7fb300000000, chauthtok = 0x0}}, former = {
    choice = -1, depth = 0, impression = 0, status = 0, substates = 0x0, fail_user = 0,
    want_user = 0, prompt = 0x0, update = PAM_FALSE},
  mod_name = 0xffffffff <error: Cannot access memory at address 0xffffffff>, mod_argc = 0,
  mod_argv = 0x0, choice = 0, audit_state = 0}

Not sure if it might be a threading issue