Re: Patch for definition of NULL

[Tim Janik <timj gtk org>]

On Wed, 11 Jul 2001, Kaz Kylheku wrote:

> A correct definition of NULL is simply 0. That works for C and C++.
> In C, (void *) 0 is also a null pointer constant (and not a pointer
> of type void *, note well), which is a good idea, because it
> traps incorrect uses, where NULL appears in a non-pointer context.
> 
> I have no idea why Solaris switches between 0 and 0L; probably someone
> clueless is maintaining the header. A zero-valued integral constant expression
> is a null pointer constant. It doesn't matter if it's long, unsigned
> or whatever. If they have a good reason, correct me.
> 
> So if I had to define NULL, I would write:
> 
>     #ifdef __cplusplus
>     #define NULL 0
>     #else
>     #define NULL ((void *) 0)
>     #endif

jup, this is actually what i'd like to see preserved,
NULL evaluating to a pointer expression in C to catch uses
in non-pointer contexts.


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ciaoTJ