Re: [Outreachy kernel] [PATCH] Staging: lustre: lmv: Remove unneeded do-while(0)

[Greg KH <gregkh@linuxfoundation.org>]

On Mon, Feb 15, 2016 at 04:28:19PM +0530, Bhumika Goyal wrote:
> do {} while (0) wrapper in a single statement macro is unneeded.

Are you sure?  You can easly break code by changing this.

> Also its ok to keep empty #define here to avoid "statement with
> no effect" warning.
> 
> Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
> ---
>  drivers/staging/lustre/lustre/lmv/lmv_obd.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/staging/lustre/lustre/lmv/lmv_obd.c b/drivers/staging/lustre/lustre/lmv/lmv_obd.c
> index 733222c..7a31bd6 100644
> --- a/drivers/staging/lustre/lustre/lmv/lmv_obd.c
> +++ b/drivers/staging/lustre/lustre/lmv/lmv_obd.c
> @@ -2147,7 +2147,7 @@ static void lmv_adjust_dirpages(struct page **pages, int ncfspgs, int nlupgs)
>  	LASSERTF(nlupgs == 0, "left = %d", nlupgs);
>  }
>  #else
> -#define lmv_adjust_dirpages(pages, ncfspgs, nlupgs) do {} while (0)
> +#define lmv_adjust_dirpages(pages, ncfspgs, nlupgs)

That's scary, please leave it alone, unless you audited all users of
this call?  Hint, think about if this call was used as the result of an
if() statement?

thanks,

greg k-h