On Wed, Feb 08, 2006 at 02:47:12PM -0800, David S. Miller wrote:
> From: David Stevens <[EMAIL PROTECTED]>
> Date: Wed, 8 Feb 2006 14:45:08 -0800
>
> > Why would sparse complain about this? 0 is a well-defined
> > pointer value (the only value guaranteed to be by the language).
>
> Because sparse goes beyond the standards and tries to
> catch cases that usually end up being bugs.
Well to be frank the only significant NULL/0 bug that I know can't
be caught by converting 0 to NULL anyway. The bug only exists on
architectures where the representations of null-pointers of types
are different. On those architectures, if you have something like
int func(char *fmt, ...);
...
func("foo", NULL);
Then this may break if func actually expected a int * while NULL
could be something different altogether. The only safe way to
write this is to have
func("foo", (int *)NULL);
or
func("foo", (int *)0);
Cheers,
--
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Email: Herbert Xu ~{PmV>HI~} <[EMAIL PROTECTED]>
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