diff --git a/slirp/dhcpv6.h b/slirp/dhcpv6.h
index 9189cd3f2d..3373f6cb89 100644
--- a/slirp/dhcpv6.h
+++ b/slirp/dhcpv6.h
@@ -17,6 +17,9 @@
                             0x00, 0x00, 0x00, 0x00,\
                             0x00, 0x01, 0x00, 0x02 } }
 
+#define in6_dhcp_multicast(a)\
+    in6_equal(a, &(struct in6_addr)ALLDHCP_MULTICAST)
+
 void dhcpv6_input(struct sockaddr_in6 *srcsas, struct mbuf *m);
 
 #endif
diff --git a/slirp/udp6.c b/slirp/udp6.c
index 9fa314bc2d..7c4a6b003a 100644
--- a/slirp/udp6.c
+++ b/slirp/udp6.c
@@ -65,7 +65,7 @@ void udp6_input(struct mbuf *m)
     /* handle DHCPv6 */
     if (ntohs(uh->uh_dport) == DHCPV6_SERVER_PORT &&
         (in6_equal(&ip->ip_dst, &slirp->vhost_addr6) ||
-         in6_equal(&ip->ip_dst, &(struct in6_addr)ALLDHCP_MULTICAST))) {
+         in6_dhcp_multicast(&ip->ip_dst))) {
         m->m_data += iphlen;
         m->m_len -= iphlen;
         dhcpv6_input(&lhost, m);