Invalid parameter passed to C runtime function.

[Thomas 63]

Hello all

I receive the above mentioned error message when I try to print a label, multiple times (about 20) if I use the printer "Adobe PDF". If I use other printers, like "Microsoft Print to PDF", or physical printers, it appears only once, but still it appears.
The print works fine though.
Can I avoid these messages or should I just live with them?

void MainWindow::on_drucken_2_clicked(){
    QPrinter drucker;
    drucker.setPrinterName(ui->select_drucker->currentText());
    QPainter painter(&drucker);
    ui->etikett_entwurf->render(&painter);
}