value_type operator++(int) volatile noexcept;
value_type operator++(int) noexcept;
value_type operator--(int) volatile noexcept;
value_type operator--(int) noexcept;
value_type operator++() volatile noexcept;
value_type operator++() noexcept;
value_type operator--() volatile noexcept;
value_type operator--() noexcept;