QGraphicsEllipseItem with empty constructor causes Abort trap 6 on Mavericks

On Mavericks, instantiating QGraphicsEllipseItem with no parameters causes the following error:

Assertion failed: (CGFloatIsValid && CGFloatIsValid), function void CGPathAddArc(CGMutablePathRef, const CGAffineTransform *, CGFloat, CGFloat, CGFloat, CGFloat, CGFloat, bool), file Paths/CGPath.cc, line 279.
Abort trap: 6

CGPathAddArc() in OS X's Paths/CGPath.cc raised a warning about this in Snow Leopard, and now raises an Abort trap in Mavericks.

Qt 4.8 documentation still condones empty constructor: http://qt-project.org/doc/qt-4.8/qgraphicsellipseitem.html#QGraphicsEllipseItem

Workaround is to use dummy x and y parameters when instantiating QGraphicsEllipseItem.