#include "../Eigen/Core" using namespace Eigen; void call_ref(Ref<const Matrix3f, 0, OuterStride<2>>) {} int main() { MatrixXf a(6, 2); Map<const Matrix3f, 0, OuterStride<Dynamic>> md(a.data(), OuterStride<Dynamic>(2)); Map<const Matrix3f, 0, OuterStride<2>> m2(a.data()); #ifdef EIGEN_SHOULD_FAIL_TO_BUILD call_ref(md); #else call_ref(m2); #endif }