[Ecls-list] Problem building from git

Geo Carncross geocar at gmail.com
Tue Feb 3 11:24:19 UTC 2009

2009/2/1 Gabriel Dos Reis <gdr at integrable-solutions.net>

> On Sun, Feb 1, 2009 at 6:52 PM, Geo Carncross <geocar at gmail.com> wrote:
> > On Sun, Feb 1, 2009 at 3:50 PM, Gabriel Dos Reis
> > <gdr at integrable-solutions.net> wrote:
> >>
> >>   (int)(intptr_t)file
> >>
> >> since intptr_t is garanteed to be precise enough to hold
> >> a value of type void*.
> >
> > Well, casting it to (int) [if that causes problems] would simply truncate
> it
> > again anyway- even though it was originally cast to intptr_t
> >
> In earlier conversation, Juanjo seemed to suggest that
> the value there really was an int. So the truncation was OK.
> My point in my preceding message is that the mapping
> from void* to int is highly unportable (anyone to guess standard
> semantics?), compared to the mapping from void* to intptr_t,
> which although implementation-defined is guaranteed to yield
> the original int value back.

That's true. I couldn't find where you were talking about in c/file.d - I
just saw all the FILE* packs into that file. field (and back again) and
assumed it was one of those.

> My personal inclination would be to use a union of void* and int,
> and select the appropriate field, thereby not depending on any
> implementation defined assumption at all.  That also would
> make the intent clearer.

I agree, but it seems like a lot of the stdio code is getting ripped out in
favor of posixish reads and writes which means it might really become an int
soon :)
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