OpenGL paint DashLine style error

I paint two lines with twice moveTo and lineTo pair in QOpenGLWidget paintGL() function，but it show three lines. The middle line is not expected.

In QDashStroker::processCurrentSubpath function，the first path line fit two (MoveToElement LineToElement pair) lines. Then in QTriangulatingStroker::process function, skipDuplicatePoints() function skip a duplicate point (double convert float lost precision)，leave one LineToElement point and line to second line.