Method destruct_on_exit

external/catch.hpp:7418–7418

                // If this is a constructor benchmark, destruct the underlying object
                template <typename U>
                void destruct_on_exit(typename std::enable_if<Destruct, U>::type* = 0) { destruct<true>(); }
                // Otherwise, don't
                template <typename U>
                void destruct_on_exit(typename std::enable_if<!Destruct, U>::type* = 0) { }