[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]
Re: lib/34516: size_t should be equivalent to unsigned long
The following reply was made to PR lib/34516; it has been noted by GNATS.
From: Christian Biere <christianbiere%gmx.de@localhost>
Subject: Re: lib/34516: size_t should be equivalent to unsigned long
Date: Sun, 20 Jan 2008 11:44:47 +0100
David Holland wrote:
> Subject: Re: lib/34516: size_t should be equivalent to unsigned long
> size_t is not, however, the *same* as unsigned long. Code that
> indiscriminately mixes size_t with unsigned long_t is no better than
> code that indiscriminately mixes size_t with unsigned int; it is not
Code which incorrectly uses unsigned long instead of size_t is
comparatively rare and it's unlikely to happen by accident. Abuse of
int instead of proper use of size_t is wide-spread and the result of
implicit integer promotion is very often int.
> It is not clear to me that there is any particular merit to
> associated with picking one way over the other.
It eases writing 64-bit clean code on 32-bit machines. This matters
more for third-party code than NetBSD itself.
> C does not support newtypes, so there is no way to avoid masking some
> such set of coding errors.
The conclusion is incorrect. I provided some examples in the initial
> Furthermore, the precise expansion of size_t is gcc's choice, because
> gcc "knows" the type signatures of various standard functions, so we
> can't or shouldn't change it in NetBSD even if there were a good
> argument in favor.
It's not so much GCC's choice because other 32-bit targets don't have
size_t as unsigned int. It's simply a question of editing machine/ansi.h.
I've fixed this locally for myself long ago and never had such a hidden
problem again. If I'm the only one who cares and/or if it's too hard to
change this historical decision, it might very well be appropriate to
close this PR.
1000 octets = 1 ko = 1 kilooctet; 1024 octets = 1 Kio = 1 kibioctet
1000^2 octets = 1 Mo = 1 megaoctet; 1024^2 octets = 1 Mio = 1 mebioctet
1000^3 octets = 1 Go = 1 gigaoctet; 1024^3 octets = 1 Gio = 1 gibioctet
Main Index |
Thread Index |