Re: CVS commit: src/sys/dev/i2c

[Matt Thomas <matt%3am-software.com@localhost>]

On Jul 28, 2012, at 10:52 PM, David Holland wrote:

> On Sat, Jul 28, 2012 at 10:22:46PM -0700, Matt Thomas wrote:
>>>> Modified Files:
>>>>    src/sys/dev/i2c: g760a.c
>>>> 
>>>> Log Message:
>>>> Use (void *) instead of (type **) which gcc complains about.
>>> 
>>> At least one of these casts is discarding const and writing to the
>>> const object returned by sysctl_createv().
>> 
>> const foo ** is not pointer to const, it's a pointer to a pointer to const.
>> so void * does not discard const.
> 
> It does; it's passing foo ** to a const foo ** argument and thereby
> discarding the const on the returned pointer.

No, it's passing void * which is ignoring, not discarding, the
'const foo *' and just using the last * which does not have a
const qualifier (if it did, it would const foo * const *).