diff --git a/src/api/api_msg.c b/src/api/api_msg.c
index ad3d78e0..b327e1b8 100644
--- a/src/api/api_msg.c
+++ b/src/api/api_msg.c
@@ -1811,7 +1811,7 @@ lwip_netconn_do_join_leave_group(struct api_msg_msg *msg)
  * signaling the semaphore.
  */
 static void
-lwip_netconn_do_dns_found(const char *name, ip_addr_t *ipaddr, void *arg)
+lwip_netconn_do_dns_found(const char *name, const ip_addr_t *ipaddr, void *arg)
 {
   struct dns_api_msg *msg = (struct dns_api_msg*)arg;
 
diff --git a/src/include/lwip/dns.h b/src/include/lwip/dns.h
index ef1ad8ce..a3c0927d 100644
--- a/src/include/lwip/dns.h
+++ b/src/include/lwip/dns.h
@@ -86,7 +86,7 @@ struct local_hostlist_entry {
  *        or NULL if the name could not be found (or on any other error).
  * @param callback_arg a user-specified callback argument passed to dns_gethostbyname
 */
-typedef void (*dns_found_callback)(const char *name, ip_addr_t *ipaddr, void *callback_arg);
+typedef void (*dns_found_callback)(const char *name, const ip_addr_t *ipaddr, void *callback_arg);
 
 void           dns_init(void);
 void           dns_tmr(void);