Re: sys_errlist definitions in libio stdin.h

[Roland McGrath]

The situation is that stdio.h (the libio one) declares sys_errlist, but it
does not in fact exist in libc.  It seems questionable for the declaration
to be there.  But I don't have enough information to know why (or if) it is
actually causing your build problem.

I don't know how you came to your conclusion about __USE_BSD, but I would
be surprised if you are not mistaken about that.  

libiberty should not be trying to compile its own strerror.
Its configure should have detected the system one.
That is probably your only actual problem.