QLineSeries doesn't render with OpenGL enabled

Hello,

I might have encountered a bug, unless it is limitation with OpenGL itself.

Basically, the QLineSeries doesn't render when the X values are larger than 32bit, like unix ms epoch. But only when setOpenGL is set to true.

If I disable opengl, it renders fine.

The same problem applies if I use for axis QValueAxis or QDateTimeAxis.
Only doesn't work if OpenGL is enabled.

Here are screenshots of the example code
http://imgur.com/a/MmfcU