[Reg: 5.15 -> 6.2/6.5?] QQuaternion::getAxisAndAngle() can produce NaN, even when normalized

#include <QQuaternion>

static void report (const QQuaternion& q, const QString& description)
{
    float x, y, z, angle;
    q.getAxisAndAngle(&x, &y, &z, &angle);

    qDebug().noquote() << "###" << description;
    qDebug().noquote()
            << QString("Axis: (%1, %2, %3)").arg(x).arg(y).arg(z)
            << '\t'
            << QString("Angle: %1").arg(angle)
            << '\n';
}

int main()
{
    QQuaternion q;
    q.setScalar(1.0f + std::numeric_limits<float>::epsilon());
    q.setVector(0.0025f, 0.0025f, 0.0025f);

    report(q, "Original");
    report(q.normalized(), "Used QQuaternion::normalized()");
    report(q/q.length(), "Forced manual normalization");
    report((q * 2).normalized(), "Scaled first, then QQuaternion::normalized()");
}