libio patches for glibc 2.1

[H.J. Lu]

> We need patches for:
> 
>     * -Di386 lossage.  I think we decided to go ahead and define
>     i386, except with -ansi is in effect.  Can someone provide a
>     patch for this?

I think we can provide an cpp script for linux.

> 
>     * A fix for the sigset_t problem.  I've got no opinion on what
>     the best fix is -- I'm depending on y'all to make that technical
>     decision.    
> 

I have proposed an include/g++/signal.h. If it is good enough, I
can implement the rest patch.

-- 
H.J. Lu (hjl@gnu.org)