Could you please help my with investigation?

@gdb) bt
#0 0x00007ffff77aa602 in operator<<(QDebug, QObject const*) () from /home/user/Qt5.0.2/5.0.2/gcc_64/lib/libQt5Core.so.5
#1 0x0000000000405e9c in VpnManager::vpnStopHandler (this=0x42fa60, exitCode=0) at vpnmanager.cpp:149
#2 0x0000000000408a0e in VpnManager::qt_static_metacall (_o=0x42fa60, _c=QMetaObject::InvokeMetaMethod, _id=0, _a=0x7fffffffdf40) at moc_vpnmanager.cpp:79
#3 0x00007ffff77aaf01 in QMetaObject::activate(QObject*, int, int, void**) () from /home/user/Qt5.0.2/5.0.2/gcc_64/lib/libQt5Core.so.5
#4 0x00007ffff76dd6b1 in QProcess::finished(int) () from /home/user/Qt5.0.2/5.0.2/gcc_64/lib/libQt5Core.so.5
#5 0x00007ffff76e2092 in ?? () from /home/user/Qt5.0.2/5.0.2/gcc_64/lib/libQt5Core.so.5
#6 0x00007ffff76e235e in ?? () from /home/user/Qt5.0.2/5.0.2/gcc_64/lib/libQt5Core.so.5
#7 0x00007ffff77aaf01 in QMetaObject::activate(QObject*, int, int, void**) () from /home/user/Qt5.0.2/5.0.2/gcc_64/lib/libQt5Core.so.5
#8 0x00007ffff78160fe in QSocketNotifier::activated(int, QSocketNotifier::QPrivateSignal) () from /home/user/Qt5.0.2/5.0.2/gcc_64/lib/libQt5Core.so.5
#9 0x00007ffff77b7081 in QSocketNotifier::event(QEvent*) () from /home/user/Qt5.0.2/5.0.2/gcc_64/lib/libQt5Core.so.5
#10 0x00007ffff7785add in QCoreApplication::notify(QObject*, QEvent*) () from /home/user/Qt5.0.2/5.0.2/gcc_64/lib/libQt5Core.so.5
#11 0x00007ffff77857c4 in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /home/user/Qt5.0.2/5.0.2/gcc_64/lib/libQt5Core.so.5
#12 0x00007ffff77ccc26 in ?? () from /home/user/Qt5.0.2/5.0.2/gcc_64/lib/libQt5Core.so.5
#13 0x00007ffff5c1fd53 in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#14 0x00007ffff5c200a0 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#15 0x00007ffff5c20164 in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#16 0x00007ffff77cd514 in QEventDispatcherGlib::processEvents(QFlagsQEventLoop::ProcessEventsFlag) () from /home/user/Qt5.0.2/5.0.2/gcc_64/lib/libQt5Core.so.5
#17 0x00007ffff778469b in QEventLoop::exec(QFlagsQEventLoop::ProcessEventsFlag) () from /home/user/Qt5.0.2/5.0.2/gcc_64/lib/libQt5Core.so.5
#18 0x00007ffff7787c3e in QCoreApplication::exec() () from /home/user/Qt5.0.2/5.0.2/gcc_64/lib/libQt5Core.so.5
#19 0x0000000000403125 in main (argc=1, argv=0x7fffffffe718) at main.cpp:29
(gdb) frame 1
#1 0x0000000000405e9c in VpnManager::vpnStopHandler (this=0x42fa60, exitCode=0) at vpnmanager.cpp:149
149 qDebug() << timerList.at(i) << endl;
(gdb) p timerList
$1 = {{p = {static shared_null = {ref = {atomic = {_q_value = -1}}, alloc = 0, begin = 0, end = 0, array = {0x0}}, d = 0x432f30}, d = 0x432f30}}
(gdb) p i
$2 = 0
(gdb) p timerList.at(0)
$3 = (QTimer * const&) @0x432f88: 0x42fb50
(gdb) p timerList.size()
$4 = 3@