Re: Making --with-wide-int the default

[David Kastrup <dak@gnu.org>]

"Stephen J. Turnbull" <stephen@xemacs.org> writes:

> David Kastrup writes:
>
>  > Instead of going to 64-bit unilaterally it would seem to make more
>  > sense to me to degrade gracefully into gmp.  GUILE does that, I
>  > think that XEmacs or SXEmacs can do it,
>
> XEmacs can't handle greater than 1 GB buffers on a 32-bit machine.
> Yes, when bignums are enabled Lisp arithmetic will automatically
> overflow to bignums (and bigfloats), but internal accounting for text
> objects uses EMACS_INTs, not Lisp integers.  At one time there were
> several users who preferred XEmacs to Emacs because they were
> routinely manipulating 512MB+ buffers and files.
>
> If you just want big Lisp integers, yes, bignums are nice.
>
> To be honest, I don't think it's a good idea to use bignums for
> internal indexes into text objects.  1 exabyte buffers should be
> enough to keep even the full archives of emacs-devel with room to
> spare for a while.

If a particular application warrants a particular C integral type, you
can always use the appropriate conversion routine for extracting it and
it will throw an error when the result does not fit the type.

That's the way one works with GUILE, and it's perfectly usable.  When
stuff blows up, it does so with an error message and at the limits of
the values that the C code can deal with rather than something like a
30-bit integer.

-- 
David Kastrup