Subject: Re: [PATCH 17/17] batman-adv: Avoid precedence issues in macros

From: Joe Perches <[email-masked]>
Date: Fri, 28 Oct 2016 14:13:06 -0700

On Thu, 2016-10-27 at 21:01 +0200, Simon Wunderlich wrote:
> From: Sven Eckelmann <[email-masked]>
> 
> It must be avoided that arguments to a macro are evaluated ungrouped (which
> enforces normal operator precendence). Otherwise the result of the macro
> is not well defined.

Curiosity:

in net/batman-adv/tp_meter.c

static int batadv_tp_send(void *arg)
{
	struct batadv_tp_vars *tp_vars = arg;
	struct batadv_priv *bat_priv = tp_vars->bat_priv;
	struct batadv_hard_iface *primary_if = NULL;
	struct batadv_orig_node *orig_node = NULL;
	size_t payload_len, packet_len;
	int err = 0;

	if (unlikely(tp_vars->role != BATADV_TP_SENDER)) {
		err = BATADV_TP_REASON_DST_UNREACHABLE;
		tp_vars->reason = err;
		goto out;
	}

	orig_node = batadv_orig_hash_find(bat_priv, tp_vars->other_end);
	if (unlikely(!orig_node)) {
		err = BATADV_TP_REASON_DST_UNREACHABLE;
		tp_vars->reason = err;
		goto out;
	}

	primary_if = batadv_primary_if_get_selected(bat_priv);
	if (unlikely(!primary_if)) {
		err = BATADV_TP_REASON_DST_UNREACHABLE;
		goto out;
	}

err is not used in the out block

Is the last if block supposed to set tp_vars->reason to err?