*: fix clang-6 SA warnings

I don't see these in CI, but my local clang-6 does emit warnings for
these.

Signed-off-by: David Lamparter <equinox@diac24.net>

lib/command.c

@@ -1197,6 +1197,7 @@ static int handle_pipe_action(struct vty *vty, const char *cmd_in,
 
 	/* retrieve action */
 	token = strsep(&working, " ");
+	assert(token);
 
 	/* match result to known actions */
 	if (strmatch(token, "include")) {

lib/csv.c

@@ -563,6 +563,8 @@ void csv_decode(csv_t *csv, char *inbuf)
 	csv_record_t *rec;
 
 	buf = (inbuf) ? inbuf : csv->buf;
+	assert(buf);
+
 	pos = strpbrk(buf, "\n");
 	while (pos != NULL) {
 		rec = calloc(1, sizeof(csv_record_t));

ospf6d/ospf6_asbr.c

@@ -732,7 +732,8 @@ void ospf6_asbr_lsa_remove(struct ospf6_lsa *lsa,
 							? 1
 							: 2,
 						buf, listcount(route->paths),
-						listcount(route->nh_list));
+						route->nh_list ?
+						listcount(route->nh_list) : 0);
 				}
 
 				if (listcount(route->paths)) {

ospf6d/ospf6_route.c

@@ -732,7 +732,7 @@ struct ospf6_route *ospf6_route_add(struct ospf6_route *route,
 		route->next = next;
 
 		if (node->info == next) {
-			assert(next->rnode == node);
+			assert(next && next->rnode == node);
 			node->info = route;
 			UNSET_FLAG(next->flag, OSPF6_ROUTE_BEST);
 			SET_FLAG(route->flag, OSPF6_ROUTE_BEST);

ospfd/ospf_snmp.c

@@ -995,7 +995,6 @@ static struct ospf_lsa *ospfLsdbLookup(struct variable *v, oid *name,
 			if (len <= 0)
 				type_next = 1;
 			else {
-				len = 1;
 				type_next = 0;
 				*type = *offset;
 			}

staticd/static_vty.c

@@ -88,8 +88,8 @@ static struct list *static_list;
 
 static int static_list_compare_helper(const char *s1, const char *s2)
 {
-	/* Are Both NULL */
-	if (s1 == s2)
+	/* extra (!s1 && !s2) to keep SA happy */
+	if (s1 == s2 || (!s1 && !s2))
 		return 0;
 
 	if (!s1 && s2)

zebra/zebra_fpm_protobuf.c

@@ -129,6 +129,7 @@ static inline int add_nexthop(qpb_allocator_t *allocator, Fpm__AddRoute *msg,
 	}
 
 	// TODO: Use src.
+	(void)src;
 
 	return 1;
 }