There are specializations of the atomic
class template for the integral types
char,
signed char,
unsigned char,
short,
unsigned short,
int,
unsigned int,
long,
unsigned long,
long long,
unsigned long long,
char8_t,
char16_t,
char32_t,
wchar_t,
and any other types needed by the typedefs in the header <cstdint>.

For each such type integral, the specialization
atomic<integral> provides additional atomic operations appropriate to integral types.

namespace std { template<> struct atomic<integral> { using value_type = integral; using difference_type = value_type; static constexpr bool is_always_lock_free = implementation-defined; bool is_lock_free() const volatile noexcept; bool is_lock_free() const noexcept; void store(integral, memory_order = memory_order::seq_cst) volatile noexcept; void store(integral, memory_order = memory_order::seq_cst) noexcept; integral load(memory_order = memory_order::seq_cst) const volatile noexcept; integral load(memory_order = memory_order::seq_cst) const noexcept; operator integral() const volatile noexcept; operator integral() const noexcept; integral exchange(integral, memory_order = memory_order::seq_cst) volatile noexcept; integral exchange(integral, memory_order = memory_order::seq_cst) noexcept; bool compare_exchange_weak(integral&, integral, memory_order, memory_order) volatile noexcept; bool compare_exchange_weak(integral&, integral, memory_order, memory_order) noexcept; bool compare_exchange_strong(integral&, integral, memory_order, memory_order) volatile noexcept; bool compare_exchange_strong(integral&, integral, memory_order, memory_order) noexcept; bool compare_exchange_weak(integral&, integral, memory_order = memory_order::seq_cst) volatile noexcept; bool compare_exchange_weak(integral&, integral, memory_order = memory_order::seq_cst) noexcept; bool compare_exchange_strong(integral&, integral, memory_order = memory_order::seq_cst) volatile noexcept; bool compare_exchange_strong(integral&, integral, memory_order = memory_order::seq_cst) noexcept; integral fetch_add(integral, memory_order = memory_order::seq_cst) volatile noexcept; integral fetch_add(integral, memory_order = memory_order::seq_cst) noexcept; integral fetch_sub(integral, memory_order = memory_order::seq_cst) volatile noexcept; integral fetch_sub(integral, memory_order = memory_order::seq_cst) noexcept; integral fetch_and(integral, memory_order = memory_order::seq_cst) volatile noexcept; integral fetch_and(integral, memory_order = memory_order::seq_cst) noexcept; integral fetch_or(integral, memory_order = memory_order::seq_cst) volatile noexcept; integral fetch_or(integral, memory_order = memory_order::seq_cst) noexcept; integral fetch_xor(integral, memory_order = memory_order::seq_cst) volatile noexcept; integral fetch_xor(integral, memory_order = memory_order::seq_cst) noexcept; atomic() noexcept = default; constexpr atomic(integral) noexcept; atomic(const atomic&) = delete; atomic& operator=(const atomic&) = delete; atomic& operator=(const atomic&) volatile = delete; integral operator=(integral) volatile noexcept; integral operator=(integral) noexcept; integral operator++(int) volatile noexcept; integral operator++(int) noexcept; integral operator--(int) volatile noexcept; integral operator--(int) noexcept; integral operator++() volatile noexcept; integral operator++() noexcept; integral operator--() volatile noexcept; integral operator--() noexcept; integral operator+=(integral) volatile noexcept; integral operator+=(integral) noexcept; integral operator-=(integral) volatile noexcept; integral operator-=(integral) noexcept; integral operator&=(integral) volatile noexcept; integral operator&=(integral) noexcept; integral operator|=(integral) volatile noexcept; integral operator|=(integral) noexcept; integral operator^=(integral) volatile noexcept; integral operator^=(integral) noexcept; }; }

The atomic integral specializations
are standard-layout structs.

They each have a trivial default constructor
and a trivial destructor.

The following operations perform arithmetic computations.

The key, operator, and computation correspondence is:

Table 132 — Atomic arithmetic computations

key | Op | Computation | key | Op | Computation |

add | + | addition | sub | - | subtraction |

or | | | bitwise inclusive or | xor | ^ | bitwise exclusive or |

and | & | bitwise and |

```
T fetch_key(T operand, memory_order order = memory_order::seq_cst) volatile noexcept;
T fetch_key(T operand, memory_order order = memory_order::seq_cst) noexcept;
```

Effects: Atomically replaces the value pointed to by
this with the result of the computation applied to the
value pointed to by this and the given operand.

Memory is affected according to the value of order.

These operations are atomic read-modify-write operations ([intro.multithread]).

Remarks: For signed integer types,
the result is as if the object value and parameters
were converted to their corresponding unsigned types,
the computation performed on those types, and
the result converted back to the signed type.

```
T operator op=(T operand) volatile noexcept;
T operator op=(T operand) noexcept;
```