Comment 1 for bug 1142213

I can confirm this bug. Switch the gtk theme to Raliegh causes emacs to start reliably. The relevant part of the gdb backtrace is:

#0 0x00007f48f1bf63cd in poll () from /lib/x86_64-linux-gnu/libc.so.6
#1 0x00007f48f50e915c in g_main_context_poll (n_fds=1, fds=0xee1330, timeout=-1, context=0xd51620, priority=<optimized out>)
    at /build/buildd/glib2.0-2.35.8/./glib/gmain.c:3995
#2 g_main_context_iterate (context=0xd51620, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>)
    at /build/buildd/glib2.0-2.35.8/./glib/gmain.c:3696
#3 0x00007f48f50e963a in g_main_loop_run (loop=0xee1280) at /build/buildd/glib2.0-2.35.8/./glib/gmain.c:3895
#4 0x00007f48f512b101 in g_spawn_sync (working_directory=working_directory@entry=0x0, argv=<optimized out>, envp=envp@entry=0x0,
    flags=flags@entry=G_SPAWN_SEARCH_PATH, child_setup=child_setup@entry=0x0, user_data=user_data@entry=0x0,
    standard_output=standard_output@entry=0x7fffd2ec6ad8, standard_error=standard_error@entry=0x0, exit_status=exit_status@entry=0x0,
    error=error@entry=0x0) at /build/buildd/glib2.0-2.35.8/./glib/gspawn.c:434
#5 0x00007f48f512b578 in g_spawn_command_line_sync (command_line=<optimized out>, standard_output=0x7fffd2ec6ad8, standard_error=0x0,
    exit_status=0x0, error=0x0) at /build/buildd/glib2.0-2.35.8/./glib/gspawn.c:735
#6 0x00007f48e9bca184 in Oxygen::QtSettings::kdeConfigPathList() const ()

I believe this patch to glib is ultimately responsible: https://git.gnome.org/browse/glib/commit/glib/gspawn.c?id=ce0022933c255313e010b27f977f4ae02aad1e7e