1#include "../Eigen/Core"
2
3using namespace Eigen;
4
5void call_ref(Ref<VectorXf> a) { }
6
7int main()
8{
9  VectorXf a(10);
10  DenseBase<VectorXf> &ac(a);
11#ifdef EIGEN_SHOULD_FAIL_TO_BUILD
12  call_ref(ac);
13#else
14  call_ref(ac.derived());
15#endif
16}
17