Standards compliant preprocessor arithmetic

[Neil Booth]

Joseph S. Myers wrote:-

> Though the standard allows laxity here, I don't think it's a particularly
> good idea to use it (to treat target long as longer than it is), any more
> than it's a good idea to use laxity about whether character constants in
> #if have the same values as they do elsewhere.  OTOH long long is
> supported as an extension in C89 mode and if long long values are
> explicitly used it would be desirable for them to work in #if.

Well, you can't change the precision of a calculation once you're half-
way through it.

We could have the GNU versions of c89 and c94 use intmax_t.
Does that sound OK?

Neil.