http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50441
--- Comment #10 from Paolo Carlini <paolo.carlini at oracle dot com> 2011-09-17 21:19:05 UTC --- I'd like to have some help about the best way to figure out whether the target supports __int128_t and __uint128_t: is __CHAR_BIT__ * __SIZEOF_LONG__ >= 64 good enough?