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Hello,

I am a beginner on CGAL and I do not understand why the following little 
programm returns a segmentation fault.

Thanks,
BATOG Guillaume

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Facet_handle app2( Polyhedron P){
        return P.facets_begin();}

int main() {
        Polyhedron P;
        Point_3 p1(0,0,0), p2(0,0,1), p3(0,1,0), p4(1,0,0);
        P.make_tetrahedron(p1,p2,p3,p4);
        Vertex_handle vh1 = P.facets_begin()->halfedge()->vertex();
        Facet_handle fd = app2(P);
        Halfedge_handle hh = fd->halfedge();
        std::cerr << "All is ok." << std::endl;
        Vertex_handle vh2 = fd->halfedge()->vertex(); //segmentation fault
    return 0;}