diff --git a/core/net/uip-ds6.c b/core/net/uip-ds6.c
index 782c4a315..06788472b 100644
--- a/core/net/uip-ds6.c
+++ b/core/net/uip-ds6.c
@@ -876,8 +876,8 @@ uip_ds6_compute_reachable_time(void)
                 UIP_ND6_MIN_RANDOM_FACTOR(uip_ds6_if.base_reachable_time));
 }
 /*---------------------------------------------------------------------------*/
-uip_ds6_nbr_t*
-uip_ds6_get_least_lifetime_neighbor()
+uip_ds6_nbr_t *
+uip_ds6_get_least_lifetime_neighbor(void)
 {
   uip_ds6_nbr_t *nbr_expiring = NULL;
   uint8_t i;
diff --git a/core/net/uip-ds6.h b/core/net/uip-ds6.h
index 38df11ed4..556dc8629 100644
--- a/core/net/uip-ds6.h
+++ b/core/net/uip-ds6.h
@@ -380,6 +380,6 @@ uint32_t uip_ds6_compute_reachable_time(void); /** \brief compute random reachab
  *     A reference to the neighbor about to expire the next or NULL if
  *     table is empty.
  */
-uip_ds6_nbr_t *uip_ds6_get_least_lifetime_neighbor();
+uip_ds6_nbr_t *uip_ds6_get_least_lifetime_neighbor(void);
 
 #endif /* __UIP_DS6_H__ */