libc++ patch for max_align_t

[Howard Hinnant]

On Feb 10, 2014, at 2:25 PM, Howard Hinnant <howard.hinnant at gmail.com> wrote:

>> It seems like the old behavior follows the standard more closely. If Len
>> == 17, then _any_ c++ object with size no greater than Len includes
>> objects of size 16 and some objects of size 16 maybe have an alignment
>> requirement of 16.
> 
> Ok, I'm convinced, thanks.

I've enclosed a slightly updated patch.  I've added float as Kal suggested, but haven't added uintmax_t because of not wanting to couple <cstddef> to <cstddint>.  I have not modified the behavior, thanks to Kal.

std::__find_max_align<std::__all_types, 1>::value = 1
std::__find_max_align<std::__all_types, 2>::value = 2
std::__find_max_align<std::__all_types, 3>::value = 2
std::__find_max_align<std::__all_types, 4>::value = 4
std::__find_max_align<std::__all_types, 5>::value = 4
std::__find_max_align<std::__all_types, 6>::value = 4
std::__find_max_align<std::__all_types, 7>::value = 4
std::__find_max_align<std::__all_types, 8>::value = 8
std::__find_max_align<std::__all_types, 9>::value = 8
std::__find_max_align<std::__all_types, 10>::value = 8
std::__find_max_align<std::__all_types, 11>::value = 8
std::__find_max_align<std::__all_types, 12>::value = 8
std::__find_max_align<std::__all_types, 13>::value = 8
std::__find_max_align<std::__all_types, 14>::value = 8
std::__find_max_align<std::__all_types, 15>::value = 8
std::__find_max_align<std::__all_types, 16>::value = 16
std::__find_max_align<std::__all_types, 17>::value = 16
std::__find_max_align<std::__all_types, 18>::value = 16
std::__find_max_align<std::__all_types, 19>::value = 16
std::__find_max_align<std::__all_types, 20>::value = 16
std::__find_max_align<std::__all_types, 21>::value = 16
std::__find_max_align<std::__all_types, 22>::value = 16
std::__find_max_align<std::__all_types, 23>::value = 16
std::__find_max_align<std::__all_types, 24>::value = 16
std::__find_max_align<std::__all_types, 25>::value = 16
std::__find_max_align<std::__all_types, 26>::value = 16
std::__find_max_align<std::__all_types, 27>::value = 16
std::__find_max_align<std::__all_types, 28>::value = 16
std::__find_max_align<std::__all_types, 29>::value = 16
std::__find_max_align<std::__all_types, 30>::value = 16
std::__find_max_align<std::__all_types, 31>::value = 16
std::__find_max_align<std::__all_types, 32>::value = 16
std::__find_max_align<std::__all_types, 33>::value = 16
...

Howard
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