ill_first
ill_first(IP_V4_G_HEAD, IP_V4_G_HEAD, ctx_ptr, ipst)
ill_first(IP_V6_G_HEAD, IP_V6_G_HEAD, ctx_ptr, ipst)
ill_first(MAX_G_HEADS, MAX_G_HEADS, ctx_ptr, ipst)
extern ill_t *ill_first(int, int, ill_walk_context_t *, ip_stack_t *);
ill = ill_first(list, list, &ctx, ipst);