// Taken from
// <https://stackoverflow.com/questions/27440953/stdunique-ptr-for-c-functions-that-need-free>
struct free_deleter {
  template <typename T> void operator()(T *p) const {
    std::free(const_cast<std::remove_const_t<T> *>(p));
  }
};
template <typename T> using unique_C_ptr = std::unique_ptr<T, free_deleter>;
static_assert(sizeof(char *) == sizeof(unique_C_ptr<char>),
              ""); // ensure no overhead

      string groupname = unique_ptr<char[],decltype(std::free)*>(CCTK_GroupName(gi), std::free).get();

      string groupname = unique_C_ptr<char>(CCTK_GroupName(gi)).get();

      string groupname = unique_ptr<char[],decltype(std::free)*>(CCTK_GroupName(gi), std::free).get();

      string groupname = unique_C_ptr<char>(CCTK_GroupName(gi)).get();

    string groupname = unique_ptr<char[],decltype(std::free)*>(CCTK_GroupName(gi),std::free).get();

    string groupname = unique_C_ptr<char>(CCTK_GroupName(gi)).get();

      buf << unique_ptr<char[],decltype(std::free)*>(CCTK_GroupName(groups0[n]),std::free).get();

      buf << unique_C_ptr<char>(CCTK_GroupName(groups0[n])).get();