std::align_val_t

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Low level memory
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operator newoperator new[]

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align_val_t

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(until C++17*)

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C Library

malloc
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free
aligned_alloc (C++17)

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operator newoperator new[]
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launder (C++17)

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Defined in header`<new>`
enumclass align_val_t:std::size_t{};		(since C++17)

Bothnew-expression anddelete-expression, when used with objects whose alignment requirement is greater than__STDCPP_DEFAULT_NEW_ALIGNMENT__, pass that alignment requirement as an argument of typestd::align_val_t to the selected allocation/deallocation function.

[edit]Notes

Alignment (as obtained byalignof) has the typestd::size_t, but placement forms of allocation and deallocation functions that takestd::size_t as an additional parameter are already in use, so this type is used instead.

Feature-test macro	Value	Std	Feature
`__cpp_aligned_new`	`201606L`	(C++17)	Dynamic memory allocation for over-aligned data

[edit]See also

operator newoperator new[]	allocation functions (function)[edit]
operator deleteoperator delete[]	deallocation functions (function)[edit]

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std::align_val_t

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