Re: size_t vs "unsigned long"

From: Pierre Habouzit <madcoder@debian.org>
Date: Oct 3, 2007, 21:36 UTC
Message-ID: <20071003213601.GD28188@artemis.corp>
In-Reply-To: <200710032320.00263.wielemak@science.uva.nl>

On Wed, Oct 03, 2007 at 09:19:59PM +0000, Jan Wielemaker wrote:

Show 23 quoted lines

> On Wednesday 03 October 2007 22:48, Pierre Habouzit wrote:
> > On Wed, Oct 03, 2007 at 08:30:04PM +0000, Junio C Hamano wrote:
> > > Traditionally, inside git, we have used the length of things
> > > with "unsigned long" for pretty much anything, except where we
> > > wanted the length exactly sized we used int32_t, uint64_t and
> > > friends.
> > >
> > > A few places pass pointer to unsigned long as the second
> > > parameter to strbuf_detach(), triggering type mismatch warnings.
> > > An easy way out is to change strbuf_detach() to take a pointer
> > > to ulong but I think it is going backwards.  Most places that
> > > use "unsigned long" can safely be converted (and made more
> > > correct) to use size_t.
> >
> >   Well, afaict, on every linux archs I know of, unsigned longs and
> > size_t are the same. Though, I don't know if that holds for the msys
> > port, and if that does not holds, then a s/unsigned long/size_t/ would
> > help them. Else, for consistency sake, I believe the change is a good
> > one.
> 
> Surely on the Microsoft 64-bit compilers size_t is 64-bits and long is
> 32-bits.  Don't blame me, I'm just the messenger that learned the hard
> way ...

  Yeah, I've been wondering, and it's the information I had. well, the
information I had is that sizeof(size_t) is 4 on win32, and 8 on win64,
OTOH (and this one I'm sure), on windows, longs are 32bits on both (32
and 64 bits ABIs).

  So replacing unsigned long with size_t's will help the msys port,
hence I had some insight that this could prove useful, now I'm sure :)

-- 
·O·  Pierre Habouzit
··O                                                madcoder@debian.org
OOO                                                http://www.madism.org