failtest/diagonal_on_const_type_actually_const.cpp

#include "../Eigen/Core"

#ifdef EIGEN_SHOULD_FAIL_TO_BUILD
#define CV_QUALIFIER const
#else
#define CV_QUALIFIER
#endif

using namespace Eigen;

void foo(){
    MatrixXf m;
    Diagonal<CV_QUALIFIER MatrixXf>(m).coeffRef(0) = 1.0f;
}

int main() {}