Rich, on Wed, 24 May 2023 10:21:05 -0400 you (Rich Felker ) wrote: > On Wed, Apr 19, 2023 at 08:38:04AM +0200, Jens Gustedt wrote: > > --- > > include/stddef.h | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/include/stddef.h b/include/stddef.h > > index f25b8639..09be5fb6 100644 > > --- a/include/stddef.h > > +++ b/include/stddef.h > > @@ -24,4 +24,6 @@ > > #define offsetof(type, member) ((size_t)( (char *)&(((type > > *)0)->member) - (char *)0 )) #endif > > > > +#define unreachable() __builtin_unreachable() > > + > > #endif > > -- > > 2.34.1 > > This is a namespace violation unless protected by a C version check. That would have been my first take also. I changed these things after you (I think it was you) telling me that generally interfaces that are added in newer versions of C need not be protected for older version. I probably misunderstood something. Can you please clarify under which circumstances you want feature tests and when not? Thanks Jₑₙₛ -- :: ICube :::::::::::::::::::::::::::::: deputy director :: :: Université de Strasbourg :::::::::::::::::::::: ICPS :: :: INRIA Nancy Grand Est :::::::::::::::::::::::: Camus :: :: :::::::::::::::::::::::::::::::::::: ☎ +33 368854536 :: :: https://icube-icps.unistra.fr/index.php/Jens_Gustedt ::