QSvgGenerator does not render QSvgIconEngine based icons

    QIcon icon_svg(":/test/input.svg");
    assert(!icon_svg.isNull());
    QPixmap icn_pix(icon_svg.pixmap(32));
    assert(!icn_pix.isNull());
    QSvgGenerator gen;
    gen.setViewBox(QRect(0, 0, 256, 256));
    QBuffer contents;
    gen.setOutputDevice(&contents);
    QPainter p(&gen);

    icon_svg.paint(&p, QRect(0, 0, 32, 32));  // This does not work ...
    p.drawPixmap(QRect(64, 0, 32, 32), icn_pix);  // ... but this does

    qDebug() << "devicePixelRatioF: " << p.device()->devicePixelRatioF() << "\n";

    p.end();

    qDebug() << QString::fromUtf8(contents.buffer());