QP Solver: Solution to non convex problems

A sample test case where the solver returns solution though the problem is non-convex. The Oxford OSQP solver checks for the KKT matrix diagonal to see if the problem is convex.

template <typename _Scalar=double>
class _SimpleQP : public QP<1, 1, _Scalar>
{
public:
    _SimpleQP()
    {
        this->P << -1;
        this->q << 0;
        this->A << 1;
        this->l << -1;
        this->u << 2;
    }
};