llueder

diff --git a/core/include/rmutex.h b/core/include/rmutex.h
index 77553fb40..59f4bff40 100644
--- a/core/include/rmutex.h
+++ b/core/include/rmutex.h
@@ -24,7 +24,12 @@
 #define RMUTEX_H
 
 #include <stdint.h>
+#ifdef __cplusplus
+#include <atomic>

llueder

diff --git a/sys/include/net/ndp.h b/sys/include/net/ndp.h
index 01751bb38..00b0bf5e7 100644
--- a/sys/include/net/ndp.h
+++ b/sys/include/net/ndp.h
@@ -344,7 +344,6 @@ typedef struct __attribute__((packed)) {
     uint8_t len;            /**< length in units of 8 octets */
     network_uint16_t resv;  /**< reserved field */
     network_uint32_t ltime; /**< lifetime in seconds */
-    ipv6_addr_t addrs[];    /**< addresses of IPv6 recursive DNS servers */
 } ndp_opt_rdnss_t;