std::align_val_t

 

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定义于头文件 <new>
enum class align_val_t : std::size_t {};		(C++17 起)

当用于对齐要求大于 `__STDCPP_DEFAULT_NEW_ALIGNMENT__` 的对象时，new-expression 和 delete-expression 会将该对齐要求作为 `std::align_val_t` 类型的参数传递给选定的分配/释放函数。

注意

对齐（通过 alignof 获得）的类型是 std::size_t，但是接受 std::size_t 作为额外参数的放置形式的分配和释放函数已经在使用中，所以改用此类型。

功能测试宏	值	标准	特性
__cpp_aligned_new	201606L	(C++17)	过对齐数据的动态内存分配

参阅

operator newoperator new[]	分配函数 (函数)
operator deleteoperator delete[]	释放函数 (函数)