std::max_align_t

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max_align_t
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Runtime type information
Defined in header <cstddef>
typedef /* implementation-defined */ max_align_t;
(since C++11)

std::max_align_t is a standard-layout TrivialType (until C++26) TriviallyCopyable type (since C++26) whose alignment requirement

std::is_trivially_default_constructible_v <std:: max_align_t > is true

Notes

Pointers returned by allocation functions such as std::malloc are suitably aligned for any object, which means they are aligned at least as strictly as std::max_align_t

Example

#include <cstddef>
#include <iostream>
 
int main()
{
    std::cout << alignof(std::max_align_t) << '\n';
}

Possible output:

16

References

  • C++23 standard (ISO/IEC 14882:2024):
  • 17.2.4 Sizes, alignments, and offsets [support.types.layout] (p: 504-505)
  • C++20 standard (ISO/IEC 14882:2020):
  • 17.2.4 Sizes, alignments, and offsets [support.types.layout] (p: 507-508)
  • C++17 standard (ISO/IEC 14882:2017):
  • 21.2.4 Sizes, alignments, and offsets [support.types.layout] (p: 479)
  • C++14 standard (ISO/IEC 14882:2014):
  • 18.2 Types [support.types] (p: 443-444)
  • C++11 standard (ISO/IEC 14882:2011):
  • 18.2 Types [support.types] (p: 454-455)

See also

alignof (C++11) queries alignment requirements of a type
(operator)
(C++11)
obtains the type's alignment requirements
(class template)
(C++11)
checks if a type is a scalar type
(class template)
C documentation for max_align_t