Bounding box can possibly return a negative index (Bug #3283)

Small situation description:

I have a background-foreground segmentation process on which an ellips has been fitted and that data has been supplied to my algorithm in the form of a txt file. I want to process the boundingbox of that provided ellipse data.

For this I fit a poly to the provided ellipse data and then calculate the boundingbox.

vector<Point> fit_line;
// Note that current_ellipse is a struct containing my retrieved textfile data
ellipse2Poly( Point(current_ellipse.x_center, current_ellipse.y_center), Size(current_ellipse.width, current_ellipse.heigth), current_ellipse.angle, 0.0, 360.0, 1.0, fit_line);
Rect roi = boundingRect(fit_line);
cout << roi << endl;

All of a sudden further processing breaks down. Last outputted roi was:

[449 x 179 from (-6, 54)]

Which is actually a correct bounding box match for the given ellipse data BUT which will lead to false processing if anyone wants to do something with that data in drawing context. This because the openCV interface doesn't allow to draw anything outside the positive coordinate plane.

From the point of view of the algorithm, it is correct, however from the point of view of all the other algorithms, this is delicate and dangerous.

I suggest inserting a warning inside the boundingbox function, that puts a warning on the screen that negative indexes occur. Or are there any other suggestions?