Re: [PATCH] Use NULL instead of integer 0 in security/selinux/

[Herbert Xu]

On Sat, Jul 10, 2004 at 03:39:13AM -0600, Eric W. Biederman wrote:
> 
> I would agree that using the constant "0" in a pointer context
> when a more explicit NULL is bad form.  But "0" is the one
> legal way in C to write the NULL pointer constant.

One reason I dislike the push to use NULL everywhere is that
new-comers may feel a false sense of security when using NULL.

This will bite in places where an explicit cast is needed to turn
NULL into a null pointer of the correct type, i.e., pointer arguments
to variadic functions.

A neat trick to catch such errors is to define NULL to be 0LL.
This is perfectly legal under ANSI and will generate a different
representation on i386.

Cheers,
-- 
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Email: Herbert Xu ~{PmV>HI~} <herbert@xxxxxxxxxxxxxxxxxxx>
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