In file included from /usr/include/c++/6/algorithm:62:0,
                 from /usr/include/x86_64-linux-gnu/c++/6/bits/stdc++.h:65,
                 from /in/foo.cc:1:
/usr/include/c++/6/bits/stl_algo.h: In instantiation of '_EuclideanRingElement std::__gcd(_EuclideanRingElement, _EuclideanRingElement) [with _EuclideanRingElement = long double]':
/in/foo.cc:7:21:   required from here
/usr/include/c++/6/bits/stl_algo.h:1233:36: error: invalid operands of types 'long double' and 'long double' to binary 'operator%'
    _EuclideanRingElement __t = __m % __n;
                                ~~~~^~~~~