Re: [PATCH] staging: gdm724x: Add parenthesis to Macro arguments

[Greg KH]

On Tue, Apr 02, 2019 at 10:04:05PM -0300, Andre Dainez wrote:
> Fix checkpatch errors:
> 
> CHECK: Macro argument 'len' may be better as '(len)' to avoid precedence issues
> CHECK: Macro argument 'nlh' may be better as '(nlh)' to avoid precedence issues
> 
> Signed-off-by: Andre Dainez <andredainez@xxxxxxxxx>
> ---
>  drivers/staging/gdm724x/netlink_k.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/staging/gdm724x/netlink_k.c b/drivers/staging/gdm724x/netlink_k.c
> index 92440c3..36d88f4 100644
> --- a/drivers/staging/gdm724x/netlink_k.c
> +++ b/drivers/staging/gdm724x/netlink_k.c
> @@ -19,8 +19,8 @@ static DEFINE_MUTEX(netlink_mutex);
>  #define ND_NLMSG_SPACE(len)	(NLMSG_SPACE(len) + ND_IFINDEX_LEN)
>  #define ND_NLMSG_DATA(nlh)	((void *)((char *)NLMSG_DATA(nlh) + \
>  						  ND_IFINDEX_LEN))
> -#define ND_NLMSG_S_LEN(len)	(len + ND_IFINDEX_LEN)
> -#define ND_NLMSG_R_LEN(nlh)	(nlh->nlmsg_len - ND_IFINDEX_LEN)
> +#define ND_NLMSG_S_LEN(len)	((len) + ND_IFINDEX_LEN)

This makes sense, but:

> +#define ND_NLMSG_R_LEN(nlh)	((nlh)->nlmsg_len - ND_IFINDEX_LEN)

That does not, correct?