QFileSytemWatcher cannot have thread affinity changed

#include <QApplication>
#include <QMessageBox>
#include <QFileSystemWatcher>
#include <QThread>

int main(int argc, char *argv[])
{
  QApplication a(argc, argv);
  QThread thread;
  thread.start();
  QFileSystemWatcher *watcher = new QFileSystemWatcher();
  watcher->moveToThread(&thread);
  QMessageBox box;
  box.show();

  watcher->deleteLater();
  return a.exec();
}