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From: dhesi@cirrus.com (Rahul Dhesi)
Newsgroups: comp.std.c
Subject: Re: gcc and NULL function pointers.
Message-ID: <1991Jun27.190107.627@cirrus.com>
Date: 27 Jun 91 19:01:07 GMT
References: <25572@well.sf.ca.us> <1146.Jun2221.20.2291@kramden.acf.nyu.edu> <16506@smoke.brl.mil> <17605.Jun2607.39.3591@kramden.acf.nyu.edu>
Sender: news@cirrus.com
Organization: Cirrus Logic Inc.
Lines: 28

In <17605.Jun2607.39.3591@kramden.acf.nyu.edu>
brnstnd@kramden.acf.nyu.edu (Dan Bernstein) writes:

>'Scuse me for thinking about backwards compatibility in a standards
>group.

Good point!  Let's keep this in mind.

>By the way, I'm curious: Why is ((char *)0) ``simply wrong''?

It's wrong for the same reason that ((void *) 0) is wrong.  K&R said
that NULL is defined to be 0.  Therefore existing code that (unwisely)
uses NULL to stand for a zero in a non-pointer context may break using
either ((void *) 0) or ((char *) 0).

However, ((void *) 0) is blessed by ANSI and ((char *) 0) is not.
Therefore we may summarize:

     ((void *) 0) is ANSI-conformant but wrong.
     ((char *) 0) is not ANSI-conformant and wrong.

And the bottom line:

     All definitions of NULL other than 0 are wrong, no matter how
     much or how little ANSI-conformant they may be.
-- 
Rahul Dhesi <dhesi@cirrus.COM>
UUCP:  oliveb!cirrusl!dhesi