Division by zero problem in QTriangulatingStroker::moveTo in src/opengl/gl2paintengineex/qtriangulatingstroker.cpp

I came across a problem in QTriangulatingStroker while debugging a program I'm working on.
I'm using QGraphicsView with OpenGL and quite large coordinates (ok, my fault...).

Large, and very close coordinates (e.g. y1 = -6022459.06174 and y2 = -6022459.17404, x1=x2) are casted from qreal(double) to float in QTriangulatingStroker::moveTo() and then passed to QTriangulatingStroker::normalVector(). After being converted to float both values equal -6022459.0 and normalVector tries to divide by the difference of them thus divides by zero.

The resulting invalid normal vector (-1.#IND000) is then passed to QTriangulatingStroker::arcPoints() in "case Qt::RoundCap" leading to "QVarLengthArray<float> points" of size 0.

The following while loop is never entered and in if( invisibleJump ) "..." m_vertices.at( count + 1 ) leads to an Q_ASSERT error because count is still m_vertices.size().

Summary: floating point precision problem --> uncaught devision by zero --> array bounds exception.