QFutureWatcher not work in for(;;) loop

[Mikeeeeee]

Hi.
QFutureWatcher not work in for(;;) loop.
Without a loop, this code works, but in an for(;;) loop, the program stops and does nothing. Why so and how to fix it?

int MainWindow::checkVector(QVector<int> vector, std::string sdtMd5String)
{
    int result = 0;
    QFutureWatcher<void> futureWatcher;
    QEventLoop loop;
    connect ( this , &MainWindow::signalStopFuter, &futureWatcher, &QFutureWatcher<void>::cancel);
    futureWatcher.setFuture(QtConcurrent::map(vector,[&](const int& d){
        if(sdtMd5String == stdStringToMd5Hash(std::to_string(d))){
            qDebug()<<d<<QString::fromStdString(stdStringToMd5Hash(std::to_string(d)));
            result = d;
            signalStopFuter();
        }
    }));
    loop.exec();
    futureWatcher.waitForFinished();
    return result;
}

[Mikeeeeee]

it is work without QEventLoop loop;