std::max_align_t (3) - Linux Man Pages
Defined in header <cstddef>
typedef /*implementation-defined*/ max_align_t; (since C++11)
std::max_align_t is a trivial standard-layout type whose alignment_requirement is at least as strict (as large) as that of every scalar type.
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.
std::max_align_t is usually synonymous with the largest scalar type, which is long double on most platforms, and its alignment requirement is either 8 or 16.
// Run this code
alignof_operator queries alignment requirements of a type (since C++11)
alignment_of obtains the type's alignment requirements
is_scalar checks if a type is a scalar type