Re: What is a null pointer constant?

Jun Woong wrote:
....
> and do not forget that a s.c. program can stringize NULL and check
> at least whether it is equal to "((void *)0.0)".

The question of whether or not conformance can be checked in that
fashion has been raised many times.

On 2001-02-17 Clive D. W. Feather wrote:
> In article <3A8DB0BE.538242B3@xxxxxxxxxxxx>, Douglas A. Gwyn
> <gwyn@xxxxxxxxxxxx> writes
> >> > > > ... there was a strong consensus that strict program conformance
> >> > > > is not affected by what the standard macros expand to.
>
> >It ought to be in 7.1.2 Standard headers, but I don't see it.
> >I'm pretty sure we responded to at least one DR along those lines.
>
> DR044 question 2.
>
> | A conforming implementation need not provide strictly conforming
> | expansion of macros defined by the standard headers.


Back to Jun Woong:
> I believe that the "implementation-defined" wording given to the NPC
> is intended to requrie implementations to document their choices, not
> to allow them to exploit it in order to provide their own forms of
> the NPC.

I agree.

.

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