* cccp.c (main): Define __STDC_VERSION__ as necessary.

        * cppinit.c (cpp_handle_option): Likewise.

        * ginclude/stdarg.h (va_copy): Use __STDC_VERSION__ to
        determine when to define.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@31022 138bc75d-0d04-0410-961f-82ee72b054a4