cpplib: K+R compile fixes and small performance tweaks

[Zack Weinberg]

On Wed, Jul 12, 2000 at 04:46:29PM -0400, Kaveh R. Ghazi wrote:
>  > From: Zack Weinberg <zack@wolery.cumb.org>
>  > 
>  > cppexp.c had excessively clever macro constructs which some pre-ANSI
>  > compilers rejected.  I would like to add a -Wtraditional warning for
>  > this, but it's not clear to me exactly what the problem was.
>  > zw
> 
> There were two problems.  One was "unary plus" which is an ANSIism.
> I just checked in a patch to have -Wtraditional warn about this.

Should it be warned about inside #if expressions, too?

> The second problem was reported on nextstep, which I though used gcc
> as its compiler.  It complained about function macros whose defined
> arguments were missing/empty.
> 
> http://gcc.gnu.org/ml/gcc-bugs/2000-07/msg00258.html
> 
> I don't think this one is a traditional C problem since my K&R
> compiler accepted it fine.

Probably a bug in that compiler.

zw