Re: [PATCH linux-next-20110718] Fix build error at mm/slab.c .

[Pekka Enberg <penberg@kernel.org>]

On Wed, 20 Jul 2011, Tetsuo Handa wrote:

> ARCH_SLAB_MINALIGN might be defined as
>
>  #define ARCH_SLAB_MINALIGN __alignof__(unsigned long long)
>
> but gcc 3.3 cannot understand
>
>  #if __alignof__(unsigned long long)
>
> line.
>
>  CC      mm/slab.o
> mm/slab.c:3156:5: warning: "__alignof__" is not defined
> mm/slab.c:3156:5: missing binary operator before token "("
> make[1]: *** [mm/slab.o] Error 1
> make: *** [mm] Error 2
>
> Use "if (ARCH_SLAB_MINALIGN)" rather than "#if ARCH_SLAB_MINALIGN".
>
> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
> ---
> mm/slab.c |    5 +----
> 1 file changed, 1 insertion(+), 4 deletions(-)
>
> --- linux-3.0-next.orig/mm/slab.c
> +++ linux-3.0-next/mm/slab.c
> @@ -3153,12 +3153,9 @@ static void *cache_alloc_debugcheck_afte
> 	objp += obj_offset(cachep);
> 	if (cachep->ctor && cachep->flags & SLAB_POISON)
> 		cachep->ctor(objp);
> -#if ARCH_SLAB_MINALIGN
> -	if ((u32)objp & (ARCH_SLAB_MINALIGN-1)) {
> +	if (ARCH_SLAB_MINALIGN && ((u32)objp & (ARCH_SLAB_MINALIGN-1)))
> 		printk(KERN_ERR "0x%p: not aligned to ARCH_SLAB_MINALIGN=%d\n",
> 		       objp, ARCH_SLAB_MINALIGN);
> -	}
> -#endif
> 	return objp;

Looks good to me. Christoph?