https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114018
--- Comment #9 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to Jakub Jelinek from comment #8)
> So, do we need to define those and std::unreachable (); in their bodies or
> something similar?
Though, cmath probably can't #include <utility>, so
#ifdef _GLIBCXX_DEBUG
std::__glibcxx_assert_fail(nullptr, 0, "std::nexttoward with extended
floating point type", nullptr);
#elif defined _GLIBCXX_ASSERTIONS
__builtin_trap();
#else
__builtin_unreachable();
#endif
or something similar.
Jon, I can try to write it tomorrow if you tell me what you prefer.
