std::align_val_t

 

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語言支援 型別支援（基本型別、RTTI） 庫特性測試宏 (C++20) 程式工具 變參函式 initializer_list (C++11) is_constant_evaluated (C++20) is_within_lifetime (C++26) source_location (C++20) 協程支援 (C++20) 契約支援 (C++26) 三路比較 three_way_comparablethree_way_comparable_with (C++20)(C++20) strong_ordering (C++20) weak_ordering (C++20) partial_ordering (C++20) common_comparison_category (C++20) compare_three_way_result (C++20) compare_three_way (C++20) strong_order (C++20) weak_order (C++20) partial_order (C++20) compare_strong_order_fallback (C++20) compare_weak_order_fallback (C++20) compare_partial_order_fallback (C++20)   is_eqis_ltis_lteq (C++20)(C++20)(C++20)   is_neqis_gtis_gteq (C++20)(C++20)(C++20)

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operator newoperator new[]

operator deleteoperator delete[]

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align_val_t (C++17)

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new_handler

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nothrow

destroying_delete (C++20)

物件訪問

launder (C++17)

 

定義於標頭檔案 <new>
enum class align_val_t : std::size_t {};		(C++17 起)

當用於對齊要求大於 `__STDCPP_DEFAULT_NEW_ALIGNMENT__` 的物件時，new-expression 和 delete-expression 會將該對齊要求作為 `std::align_val_t` 型別的引數傳遞給選定的分配/釋放函式。

注意

對齊（透過 alignof 獲得）的型別是 std::size_t，但是接受 std::size_t 作為額外引數的放置形式的分配和釋放函式已經在使用中，所以改用此型別。

功能測試宏	值	標準	特性
__cpp_aligned_new	201606L	(C++17)	過對齊資料的動態記憶體分配

參閱

operator newoperator new[]	分配函式 (函式)
operator deleteoperator delete[]	釋放函式 (函式)