(gdb) run
Starting program: /home/tanu/tmp/test/test 
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[New Thread 0x7fffebf29700 (LWP 15301)]
[New Thread 0x7fffde6f9700 (LWP 15302)]
^C
Program received signal SIGINT, Interrupt.
0x00007ffff4e0718d in poll () at ../sysdeps/unix/syscall-template.S:81
81	../sysdeps/unix/syscall-template.S: No such file or directory.
(gdb) thread apply all bt

Thread 3 (Thread 0x7fffde6f9700 (LWP 15302)):
#0  0x00007ffff4e0718d in poll () at ../sysdeps/unix/syscall-template.S:81
#1  0x00007ffff4812ee4 in g_main_context_poll (priority=2147483647, n_fds=1, fds=0x7fffd80027d0, timeout=-1, context=0x7fffd8000990)
    at /tmp/buildd/glib2.0-2.42.1/./glib/gmain.c:4076
#2  g_main_context_iterate (context=context@entry=0x7fffd8000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>)
    at /tmp/buildd/glib2.0-2.42.1/./glib/gmain.c:3776
#3  0x00007ffff4812ffc in g_main_context_iteration (context=0x7fffd8000990, may_block=1) at /tmp/buildd/glib2.0-2.42.1/./glib/gmain.c:3842
#4  0x00007ffff60d9537 in QEventDispatcherGlib::processEvents (this=0x7fffd80008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:426
#5  0x00007ffff607f752 in QEventLoop::exec (this=this@entry=0x7fffde6f8e40, flags=..., flags@entry=...) at kernel/qeventloop.cpp:212
#6  0x00007ffff5e44284 in QThread::exec (this=<optimized out>) at thread/qthread.cpp:511
#7  0x00007ffff5e490de in QThreadPrivate::start (arg=0x814440) at thread/qthread_unix.cpp:345
#8  0x00007ffff58fd0a4 in start_thread (arg=0x7fffde6f9700) at pthread_create.c:309
#9  0x00007ffff4e0fccd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111

Thread 2 (Thread 0x7fffebf29700 (LWP 15301)):
#0  0x00007ffff4e0718d in poll () at ../sysdeps/unix/syscall-template.S:81
#1  0x00007ffff199e252 in poll (__timeout=-1, __nfds=1, __fds=0x7fffebf28d40) at /usr/include/x86_64-linux-gnu/bits/poll2.h:46
#2  _xcb_conn_wait (c=0x61c3c0, cond=<optimized out>, vector=0x0, count=0x0) at ../../src/xcb_conn.c:447
#3  0x00007ffff199fddf in xcb_wait_for_event (c=0x7fffebf28d40) at ../../src/xcb_in.c:622
#4  0x00007fffeeb45029 in QXcbEventReader::run (this=0x625ef0) at qxcbconnection.cpp:1046
#5  0x00007ffff5e490de in QThreadPrivate::start (arg=0x625ef0) at thread/qthread_unix.cpp:345
#6  0x00007ffff58fd0a4 in start_thread (arg=0x7fffebf29700) at pthread_create.c:309
#7  0x00007ffff4e0fccd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111

Thread 1 (Thread 0x7ffff7fbf780 (LWP 15290)):
#0  0x00007ffff4e0718d in poll () at ../sysdeps/unix/syscall-template.S:81
#1  0x00007ffff4812ee4 in g_main_context_poll (priority=2147483647, n_fds=4, fds=0x790300, timeout=-1, context=0x7fffe40016f0)
    at /tmp/buildd/glib2.0-2.42.1/./glib/gmain.c:4076
#2  g_main_context_iterate (context=context@entry=0x7fffe40016f0, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>)
    at /tmp/buildd/glib2.0-2.42.1/./glib/gmain.c:3776
#3  0x00007ffff4812ffc in g_main_context_iteration (context=0x7fffe40016f0, may_block=1) at /tmp/buildd/glib2.0-2.42.1/./glib/gmain.c:3842
#4  0x00007ffff60d9537 in QEventDispatcherGlib::processEvents (this=0x6e0880, flags=...) at kernel/qeventdispatcher_glib.cpp:426
#5  0x00007ffff607f752 in QEventLoop::exec (this=this@entry=0x7fffffffe030, flags=..., flags@entry=...) at kernel/qeventloop.cpp:212
#6  0x00007ffff60871cc in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1188
#7  0x0000000000400b0b in main (argc=1, argv=0x7fffffffe1d8) at test.cc:7