QOpenGLPaintEngine not support QPainter::Antialiasing

// The left widget is base with QOpenGLWidget, The right widget is base with QWidget
#include <QApplication>
#include <QHBoxLayout>
#include <QOpenGLWidget>
#include <QPainter>
#include <QPainterPath>

static void paint(QWidget *w)
{
    QPainter pa(w);
    QPainterPath path;

    pa.fillRect(w->rect(), Qt::black);
    path.addEllipse(QRect(50, 50, 100, 100));
    pa.setRenderHint(QPainter::Antialiasing);
    pa.setClipPath(path);
    pa.fillRect(w->rect(), Qt::red);
}

class GLWidget : public QOpenGLWidget
{
public:
    void paintEvent(QPaintEvent *e) override
    {
        paint(this);
    }
};

class Widget : public QWidget
{
public:
    void paintEvent(QPaintEvent *e) override
    {
        paint(this);
    }
};

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    QWidget main;
    QHBoxLayout layout(&main);

    GLWidget glw;
    Widget w;

    layout.addWidget(&glw);
    layout.addWidget(&w);

    main.resize(500, 500);
    main.show();

    return a.exec();
}