Errors in Intersection polygon boost

Question

I meet the following errors when I use intersection() function from boost library.

I have a vector of polygons and I want to get the intersection of each polygon with a square (((300, -90), (300, 90), (500, 90), (500, -90), (300, -90))).

In these polygons there is a polygon (((300, 90), (273.338, 31.7382), (208.263, 6.01099), (188.95, 12.8509), (161.473, 90), (300, 90))),

When I calculate the result in the following loop, the result for this polygon is wrong. the output is (((300, 90), (300, 90), (500, 90), (500, -90), (300, -90), (300, 90))). However, if I do not use the loop and only test this polygon, the intersection is empty, the result is what I expected.

This is very strange. Could someone know what is the reason?

double Analysis::GetDensity(const vector<polygon_2d>& polygon, const polygon_2d& measureArea)
{
    double density=0;
    for(vector<polygon_2d>::const_iterator polygon_iterator =   polygon.begin(); polygon_iterator!=polygon.end();polygon_iterator++)
    {
    typedef std::vector<polygon_2d > polygon_list;
    polygon_list v;
    intersection(measureArea, *polygon_iterator, v);
    if(!v.empty())
    {
        density+=area(v[0])/area(*polygon_iterator);
        if((area(v[0])/area(*polygon_iterator))>1.00001)
        {
            std::cout<<dsv(v[0])<<"\n";
            std::cout<<dsv(measureArea)<<"\n";
            std::cout<<dsv(*polygon_iterator)<<"\n";
            std::cout<<"this is a wrong result "<<area(v[0])<<'\t'<<area(*polygon_iterator)<<"\n";
            exit(EXIT_FAILURE);
        }
    }
}

}