https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63806
--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> --- No, narrowing conversion is implementation defined, and gcc defines that to the modulo 2^N wrapping, so this is not undefined behavior, and furthermore, something you'd complain about in pretty much all the code (there is no difference between implicit and explicit narrowing cast).
