https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116130
--- Comment #12 from Joseph S. Myers <jsm28 at gcc dot gnu.org> --- N3096 is a very old draft with lots of mistakes. Use N3220 instead (it has no technical changes relative to C23, though it's also missing many late editorial fixes required by ISO). Composite types for conditional expressions are as intended. [[noreturn]] is not a type attribute but a declaration attribute (and GNU noreturn on types merges differently). Accordingly, C23 deliberately does not add the new type attributes to any existing functions that were in previous C standard versions, precisely because that would invalidate existing code that used conditional expressions and was valid with previous standard versions. It *does* put [[unsequenced]] on the <stdbit.h> functions, as they are new in C23, and it would be appropriate for glibc to do likewise (when building with a compiler supporting [[__unsequenced__]]) - though as the out-of-line functions won't normally be used, and already use __attribute_const__, the effects of doing so would be small (and it's always OK not to have the attribute in the header, since any program valid with it there is also valid without it).
