[ft] FT_Outline_Get_BBox() negative overflow

[Marco Wertz]

I've encountered a strange issue with FT_Outline_Get_BBox(). When getting the 
dimensions
of the following shape bbox.yMin overflows into the negative:

        setvector(v1, 28800, 9600);
        FT_Stroker_BeginSubPath(stroker, &v1, 0);
        FT_Stroker_LineTo(stroker, &v1);

        setvector(v1, 28800, 6400);
        FT_Stroker_LineTo(stroker, &v1);
                
        setvector(v1, 28800, 10666);
        setvector(v2, 22400, 10666);
        setvector(v3, 22400, 6400);     
        FT_Stroker_CubicTo(stroker, &v1, &v2, &v3);
        
        setvector(v1, 22400, 2133);
        setvector(v2, 28800, 2133);
        setvector(v3, 28800, 6399);
        FT_Stroker_CubicTo(stroker, &v1, &v2, &v3);

Here is the result returned by FT_Outline_Get_BBox():

        BBOX: 22400 -2147474048 28866 9599

Is this a bug or have I done something wrong here? 

Small demo source attached.

Marco

test.c
Description: Text document