Re: linux 2.6.23-rc7 - 14 compile warnings

[WANG Cong <xiyou.wangcong@gmail.com>]

On Sat, Sep 22, 2007 at 10:23:59PM -0400, Gerhard Mack wrote:
>On Sat, 22 Sep 2007, WANG Cong wrote:
>
>> >Summary:
>> >  CC      mm/slub.o
>> >mm/slub.c: In function 'kfree':
>> >mm/slub.c:2491: warning: passing argument 3 of 'slab_free' discards
>> >qualifiers from pointer target type
>
>static void __slab_free(struct kmem_cache *s, struct page *page,
>                                        void *x, void *addr)
>but ..
>
>void kfree(const void *x)
>
>void is not the same as const void.
>					
>> >  CC      fs/autofs4/symlink.o
>> >fs/autofs4/symlink.c: In function 'autofs4_follow_link':
>> >fs/autofs4/symlink.c:18: warning: passing argument 2 of 'nd_set_link'
>> >discards qualifiers from pointer target type
>
>Once again ino->u.symlink is a const char and it's dropping the const.
>

slab_free(s, page, (void *)x, __builtin_return_address(0));
                   ^^^^^^^^^
I knew these things. But the explicit casts, such as the above one, mean
that we are intended to discard to qualifiers and I think gcc shouldn't
warn about this.

Regards.


WANG Cong