http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57699
--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> --- (In reply to Bernd Edlinger from comment #3) > Is this NO_IMPLICIT_EXTERN_C define set by the > configure script? It's set by headers under gcc/config/ > Should I make sure that the > configure script sets NO_IMPLICIT_EXTERN_C? Yes, but whether eCos defines it is not really relevant to this PR, which is about the general feature not whether it's used on a given platform or not.