std::atomic_flag:: clear

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std::atomic_flag
Defined in header <atomic>
void clear ( std:: memory_order order =
std:: memory_order_seq_cst ) volatile noexcept ;
(1) (since C++11)
void clear ( std:: memory_order order =
std:: memory_order_seq_cst ) noexcept ;
(2) (since C++11)

Atomically changes the state of a std::atomic_flag to clear ( false ).

If order is one of std:: memory_order_consume , std:: memory_order_acquire and std:: memory_order_acq_rel , the behavior is undefined.

Parameters

order - the memory synchronization ordering

Defect reports

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

DR Applied to Behavior as published Correct behavior
LWG 2138 C++11 order could be std:: memory_order_consume the behavior is undefined in this case

See also

atomically sets the flag to true and obtains its previous value
(public member function)
(C++11) (C++11)
atomically sets the value of the flag to false
(function)
(C++11)
defines memory ordering constraints for the given atomic operation
(enum)
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