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std::atomic_flag:: clear

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std::atomic_flag
定义于头文件 <atomic>
void clear ( std:: memory_order order =
std:: memory_order_seq_cst ) volatile noexcept ;
(1) (C++11 起)
void clear ( std:: memory_order order =
std:: memory_order_seq_cst ) noexcept ;
(2) (C++11 起)

以原子操作将 std::atomic_flag 的状态更改为清除状态（ false ）。

如果 order 是 std:: memory_order_consume 、 std:: memory_order_acquire 或 std:: memory_order_acq_rel 之一，则行为未定义。

参数

order - 内存同步顺序

缺陷报告

下列行为变更缺陷报告被追溯应用于先前发布的 C++ 标准。

缺陷报告 适用范围 发布时行为 正确行为
LWG 2138 C++11 order 可能为 std:: memory_order_consume 此情况下行为未定义

参见

原子地将标志设置为 true 并获取其先前值
(公开成员函数)
(C++11) (C++11)
原子地将标志的值设置为 false
(函数)
(C++11)
为给定的原子操作定义内存排序约束
(枚举)