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