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From: steve@groucho.ucar.edu (Steve Emmerson)
Newsgroups: comp.std.c
Subject: Re: gcc and NULL function pointers.
Message-ID: <11774@ncar.ucar.edu>
Date: 11 Jun 91 02:07:34 GMT
References: <4641@inews.intel.com> <1991Jun10.061202.25199@kithrup.COM> <1991Jun10.073125.25120@tkou02.enet.dec.com> <1991Jun10.081924.26439@kithrup.COM>
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In <1991Jun10.081924.26439@kithrup.COM> sef@kithrup.COM (Sean Eric Fagan) 
writes:

>ANSI does not require a prototype for non-variardic functions (as far as I
>can tell).  As a result, for a certain class of popular machines, under
>certain compiler options, defining NULL as 0 will be incorrect, while
>'(void*)0' is correct.

>And the program that would core-dump on this would be perfectly correct,
>according to ANSI.  The header file would, therefore, be wrong.

No.  Since the program didn't cast the macro NULL into the appropriate
type, it's relying on implementation-defined (or is it undefined?) 
behavior; hence, the program isn't strictly conforming ("correct" in
your terminology).

Steve Emmerson        steve@unidata.ucar.edu        ...!ncar!unidata!steve