FFI Report, CVS Id 1.11
Manuel M. T. Chakravarty
chak at cse.unsw.edu.au
Thu Aug 30 11:32:20 EDT 2001
Alastair David Reid <reid at cs.utah.edu> wrote,
> > | > PtrDiff
> > I must say that I rather agree with Marcin here. Let's just use Int
> > (but not Int32!). On machines with big address spaces, Ints will be
> > big. Keep it simple. Oh, and efficient!
> For all the reasons I've used in the past of avoiding future problems
> (especially those associated with Int), I disagree. But I didn't seem
> to make much headway last time so let me just make this suggestion:
> Let's add some asserts to the affected code so that we'll get warnings
> when we try to compile the code on a system that breaks these assumptions.
> Something like this:
> #if SIZEOF_INT != SIZEOF_PTR
> #error "Pointer difference operation could overflow - please fix"
To be honest, by now I am prepared to leave the status quo
as it is, which, as you say, basically forces any sensible
implementation to make `Int' as big as pointers.
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