QXcbConnection::getTimestamp runs in indefinite loop when X server shuts down

 #2 0x00007fc46bb1dcc8 in QXcbConnection::getTimestamp() () at /lib64/libQt5XcbQpa.so.5
 #3 0x00007fc46bb38e52 in QXcbNativeInterface::getTimestamp(QXcbScreen const*) () at /lib64/libQt5XcbQpa.so.5
 #4 0x00007fc46bb39cb3 in QXcbNativeInterface::nativeResourceForScreen(QByteArray const&, QScreen*) () at /lib64/libQt5XcbQpa.so.5
 #5 0x00007fc47fd2ac56 in QX11Info::getTimestamp() () at /lib64/libQt5X11Extras.so.5
 #6 0x00007fc480100d18 in KWin::Platform::updateXTime() () at /lib64/libkwin.so.5

xcb_timestamp_t QXcbConnection::getTimestamp()
{
...
    xcb_generic_event_t *event = nullptr;
    while (!event) {
        connection()->sync();
        event = eventQueue()->peek([window, dummyAtom](xcb_generic_event_t *event, int type) {
            if (type != XCB_PROPERTY_NOTIFY)
                return false;
            auto propertyNotify = reinterpret_cast<xcb_property_notify_event_t *>(event);
            return propertyNotify->window == window && propertyNotify->atom == dummyAtom;
        });
    }