QSystemTrayIcon with context menu crashes on second show()

The following code inside a QMainWindow crashes:

      QSystemTrayIcon* sysTray = new QSystemTrayIcon(this);
      QMenu *trayMenu = new QMenu(this);
      sysTray->setContextMenu(trayMenu);
      sysTray->show();
      sysTray->hide();
      sysTray->show(); // crash here

Stack trace: (sorry, not build from Qt sources)

1 QWidget::setParent(QWidget *) 0x7ffff76f69d0
2 ?? 0x7fffec27f1ba
3 ?? 0x7ffff7a22bed
4 ?? 0x7ffff7a4159e
5 QSystemTrayIcon::setVisible(bool) 0x7ffff7a22777
6 QSystemTrayIcon::show qsystemtrayicon.h 95 0x402ab5
7 MainWindow::MainWindow main.cpp 19 0x402bad
8 main main.cpp 27 0x4028cb