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std::atomic_ref<T>::fetch_and

From cppreference.com
< cpp‎ | atomic‎ | atomic ref
 
 
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Provided only when T is an integral type other than cv bool
value_type fetch_and( value_type arg,

                      std::memory_order order =

                          std::memory_order_seq_cst ) const noexcept;
(since C++20)

Atomically replaces the current value of the referenced object with the result of bitwise AND of the value and arg. This operation is a read-modify-write operation. Memory is affected according to the value of order.

This overload participates in overload resolution only if std::is_const_v<T> is false.

Contents

[edit] Parameters

arg-the other argument of bitwise AND
order-memory order constraints to enforce

[edit] Return value

The value of the referenced object, immediately preceding the effects of this function.

[edit] Example

[edit] Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DRApplied toBehavior as publishedCorrect behavior
LWG 3508
(P3323R1)
C++20fetch_and was meaningless for const Tconstrained to accept only non-const T