In Android: QNetworkAddressEntry::netmask() gives no value

void MainWindow::on_interfButton_clicked()
{
    QString text;
    QList<QNetworkInterface>  intfList = QNetworkInterface::allInterfaces();
    int  intfListLen = intfList.size();
    for (int i = 0; i < intfListLen; ++i) {
        QNetworkInterface  interface = intfList.at(i);
        QNetworkInterface::InterfaceFlags  flags = interface.flags();
        if (!flags.testFlag( QNetworkInterface::IsUp)
        || flags.testFlag( QNetworkInterface::IsPointToPoint))
            continue;

        QList<QNetworkAddressEntry>  entries = interface.addressEntries();
        int  entriesLen = entries.size();
        for (int j = 0; j < entriesLen; ++j) {
             QNetworkAddressEntry entry = entries.at(j);
            QAbstractSocket::NetworkLayerProtocol  prot = entry.ip().protocol();
            if ((prot != QAbstractSocket::IPv4Protocol) && (prot != QAbstractSocket::IPv6Protocol))
                continue;

            text += interface.name() + "  ip=" + entry.ip().toString()
                   + " mask=" + entry.netmask().toString();
            if (entry.prefixLength() < 0) {
                // TODO MW: This seemes like a bug in android/qt, any workaround?
                text += "  Bad netmask";
            }
            text += "\n\n";
        }
    }

    ui->textEdit->setPlainText(text);
}