~/work/hello-gui-build-5bbc8d-Debug % gdb ./hello-gui 
Reading symbols from /home/nikolai/work/hello-gui-build-5bbc8d-Debug/hello-gui...done.
(gdb) r
Starting program: /home/nikolai/work/hello-gui-build-5bbc8d-Debug/hello-gui 
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[New Thread 0x7fffed0b4700 (LWP 26366)]
Got bus address:  "unix:abstract=/tmp/dbus-r3o1o4BtOB,guid=b0efa7f60f15f16f1216be59000023ca" 
Connected to accessibility bus at:  "unix:abstract=/tmp/dbus-r3o1o4BtOB,guid=b0efa7f60f15f16f1216be59000023ca" 
Registered DEC:  true 
QXcbConnection: XCB error: 179 (Unknown), sequence: 143, resource id: 0, major code: 153 (Unknown), minor code: 20
QDBusConnection: name 'org.a11y.atspi.Registry' had owner '' but we thought it was ':1.1'


^C
Program received signal SIGINT, Interrupt.
0x00007ffff652eb03 in __GI___poll (fds=<optimized out>, nfds=<optimized out>, timeout=<optimized out>)
    at ../sysdeps/unix/sysv/linux/poll.c:87
87	../sysdeps/unix/sysv/linux/poll.c: No such file or directory.
(gdb) bt
#0  0x00007ffff652eb03 in __GI___poll (fds=<optimized out>, nfds=<optimized out>, timeout=<optimized out>)
    at ../sysdeps/unix/sysv/linux/poll.c:87
#1  0x00007ffff44db036 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007ffff44db164 in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007ffff6fee4af in QEventDispatcherGlib::processEvents (this=0x609570, flags=...)
    at kernel/qeventdispatcher_glib.cpp:423
#4  0x00007ffff6f799c3 in QEventLoop::processEvents (this=0x7fffffffe4c0, flags=...) at kernel/qeventloop.cpp:136
#5  0x00007ffff6f79c91 in QEventLoop::exec (this=0x7fffffffe4c0, flags=...) at kernel/qeventloop.cpp:212
#6  0x00007ffff6f7ced7 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:976
#7  0x00007ffff5e0d5a3 in QGuiApplication::exec () at kernel/qguiapplication.cpp:1071
#8  0x00007ffff758242c in QApplication::exec () at kernel/qapplication.cpp:2920
#9  0x0000000000402bff in main (argc=1, argv=0x7fffffffe688) at ../hello-gui/main.cpp:40
(gdb) bt full
#0  0x00007ffff652eb03 in __GI___poll (fds=<optimized out>, nfds=<optimized out>, timeout=<optimized out>)
    at ../sysdeps/unix/sysv/linux/poll.c:87
        resultvar = <optimized out>
        oldtype = 0
        result = <optimized out>
#1  0x00007ffff44db036 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
No symbol table info available.
#2  0x00007ffff44db164 in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
No symbol table info available.
#3  0x00007ffff6fee4af in QEventDispatcherGlib::processEvents (this=0x609570, flags=...)
    at kernel/qeventdispatcher_glib.cpp:423
        d = 0x609880
        canWait = true
        savedFlags = {i = 0}
        result = false
#4  0x00007ffff6f799c3 in QEventLoop::processEvents (this=0x7fffffffe4c0, flags=...) at kernel/qeventloop.cpp:136
        d = 0x655d10
#5  0x00007ffff6f79c91 in QEventLoop::exec (this=0x7fffffffe4c0, flags=...) at kernel/qeventloop.cpp:212
        locker = {val = 6321184}
        __PRETTY_FUNCTION__ = "int QEventLoop::exec(QEventLoop::ProcessEventsFlags)"
        ref = {d = 0x655d10, locker = @0x7fffffffe430, exceptionCaught = true}
        app = 0x7fffffffe580
        d = 0x655d10
#6  0x00007ffff6f7ced7 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:976
        threadData = 0x606730
        __PRETTY_FUNCTION__ = "static int QCoreApplication::exec()"
        eventLoop = {<QObject> = {_vptr.QObject = 0x7ffff7412530, static staticMetaObject = {d = {superdata = 0x0, 
                stringdata = 0x7ffff7418120, data = 0x7ffff70e9140, 
                static_metacall = 0x7ffff6fbf9be <QObject::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x0, extradata = 0x0}}, d_ptr = {d = 0x655d10}, static staticQtMetaObject = {d = {superdata = 0x0, 
                stringdata = 0x7ffff7418c60, data = 0x7ffff70f7ce0, static_metacall = 0, relatedMetaObjects = 0x0, 
                extradata = 0x0}}}, static staticMetaObject = {d = {superdata = 0x7ffff740f100, 
              stringdata = 0x7ffff7428200, data = 0x7ffff70fd400, 
              static_metacall = 0x7ffff7046d68 <QEventLoop::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x0, extradata = 0x0}}}
        returnCode = 0
#7  0x00007ffff5e0d5a3 in QGuiApplication::exec () at kernel/qguiapplication.cpp:1071
No locals.
#8  0x00007ffff758242c in QApplication::exec () at kernel/qapplication.cpp:2920
No locals.
#9  0x0000000000402bff in main (argc=1, argv=0x7fffffffe688) at ../hello-gui/main.cpp:40
        a = {<QGuiApplication> = {<QCoreApplication> = {<QObject> = {_vptr.QObject = 0x7ffff7d93cb0, 
                static staticMetaObject = {d = {superdata = 0x0, stringdata = 0x7ffff7418120, data = 0x7ffff70e9140, 
                    static_metacall = 0x7ffff6fbf9be <QObject::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x0, extradata = 0x0}}, d_ptr = {d = 0x607240}, static staticQtMetaObject = {d = {
                    superdata = 0x0, stringdata = 0x7ffff7418c60, data = 0x7ffff70f7ce0, static_metacall = 0, 
                    relatedMetaObjects = 0x0, extradata = 0x0}}}, static staticMetaObject = {d = {
                  superdata = 0x7ffff740f100, stringdata = 0x7ffff7417f60, data = 0x7ffff70e46a0, 
                  static_metacall = 0x7ffff6f7ffba <QCoreApplication::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x0, extradata = 0x0}}, static self = 0x7fffffffe580}, static staticMetaObject = {d = {
                superdata = 0x7ffff740ee00, stringdata = 0x7ffff643ace0, data = 0x7ffff6125de0, 
                static_metacall = 0x7ffff5e12300 <QGuiApplication::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x0, extradata = 0x0}}}, static staticMetaObject = {d = {superdata = 0x7ffff642f8a0, 
              stringdata = 0x7ffff7dbe4a0, data = 0x7ffff79eb960, 
              static_metacall = 0x7ffff75867f0 <QApplication::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x0, extradata = 0x0}}}
        w = {<QMainWindow> = {<QWidget> = {<QObject> = {_vptr.QObject = 0x604bd0, static staticMetaObject = {d = {
                    superdata = 0x0, stringdata = 0x7ffff7418120, data = 0x7ffff70e9140, 
                    static_metacall = 0x7ffff6fbf9be <QObject::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x0, extradata = 0x0}}, d_ptr = {d = 0x643c10}, static staticQtMetaObject = {d = {
                    superdata = 0x0, stringdata = 0x7ffff7418c60, data = 0x7ffff70f7ce0, static_metacall = 0, 
                    relatedMetaObjects = 0x0, extradata = 0x0}}}, <QPaintDevice> = {_vptr.QPaintDevice = 0x604d88, 
                painters = 0, reserved = 0x0}, static staticMetaObject = {d = {superdata = 0x7ffff740f100, 
                  stringdata = 0x7ffff7dbea00, data = 0x7ffff79f0f40, 
                  static_metacall = 0x7ffff75d31e0 <QWidget::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x0, extradata = 0x0}}, data = 0x643d38}, static staticMetaObject = {d = {
                superdata = 0x7ffff7d948e0, stringdata = 0x7ffff7dd46c0, data = 0x7ffff7a91b60, 
                static_metacall = 0x7ffff79de270 <QMainWindow::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x7ffff7dd4a60, extradata = 0x0}}}, static staticMetaObject = {d = {superdata = 0x7ffff7db1660, 
              stringdata = 0x4036a0, data = 0x4036e0, 
              static_metacall = 0x4033b4 <MainWindow::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, 
              relatedMetaObjects = 0x0, extradata = 0x0}}, ui = 0x63c340}
(gdb)