QMenu bug when removing last action

main.cpp

#include <cstdio>

#include <QtCore/qobject.h>
#include <QtWidgets/qaction.h>
#include <QtWidgets/qapplication.h>
#include <QtWidgets/qmainwindow.h>
#include <QtWidgets/qmenubar.h>

QMenu * more_menu = 0;

void append()
{
  printf("append one item to the menu\n");
  QAction * action = new QAction("item", more_menu);
  more_menu->addAction(action);
}

void pop()
{
  QList<QAction *> actions = more_menu->actions();
  if (!actions.isEmpty()) {
    QAction * action = actions.takeLast();
    if (action->isVisible()) {
      printf("pop one item from the menu\n");
      more_menu->removeAction(action);
    } else {
      printf("no popping the hidden dummy action\n");
    }
  } else {
    printf("nothing to pop\n");
  }
}

int main(int argc, char ** argv)
{
  QApplication * app = new QApplication(argc, argv);
  QMainWindow * main_window = new QMainWindow();
  QMenuBar * menu_bar = main_window->menuBar();

  QMenu * file_menu = menu_bar->addMenu("Command");

  more_menu = menu_bar->addMenu("List");

  {
    QAction * action = new QAction("Append", file_menu);
    QObject::connect(action, &QAction::triggered, append);
    file_menu->addAction(action);
  }

  {
    QAction * action = new QAction("Pop", file_menu);
    QObject::connect(action, &QAction::triggered, pop);
    file_menu->addAction(action);
  }

  /*
  {
    QAction * action = new QAction("Dummy", more_menu);
    action->setVisible(false);
    more_menu->addAction(action);
  }
  */

  main_window->resize(400, 100);
  main_window->show();

  return app->exec();
}