https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108613
--- Comment #5 from Jonathan Wakely <redi at gcc dot gnu.org> --- (In reply to Serdar Sanli from comment #0) > https://godbolt.org/z/M1o34e6cx > > Below code crashes GCC versions starting with GCC 12. It is only stuff from > std library headers, I've copied bits from preprocessed output. ... > template< class _Tp> using __is_signed_integer = __is_one_of< _Tp , > signed char, signed short, signed int, signed long, signed long long, > signed __int128_t> ; Where did you get this from? The <type_traits> header uses signed __int128 here, not signed __int128_t.