libc++'s type_traits header doesn’t properly support |__int128 and
__uint128 integers as type parameter values for is_integral, is_signed,
is_unsigned, make_signed and make_unsigned. Is this by design, or would
a patch be welcome?
I think this would be great personally.
A related question is about long double.
On Windows, what to do about sizeof(long double) for MSVC being 8 and sizeof(long double) for g++ being 16.