diff --git a/Demo/Common/ethernet/FreeTCPIP/net/uip.h b/Demo/Common/ethernet/FreeTCPIP/net/uip.h
index 3cfad7bef..3a0ed1989 100644
--- a/Demo/Common/ethernet/FreeTCPIP/net/uip.h
+++ b/Demo/Common/ethernet/FreeTCPIP/net/uip.h
@@ -69,14 +69,16 @@
 
 	typedef uip_ip6addr_t	uip_ipaddr_t;
 #else /* UIP_CONF_IPV6 */
-	#include "pack_struct_start.h"
-		typedef union			uip_ip4addr_t
-		{
-			u8_t	u8[4];	/* Initializer, must come first!!! */
-			u16_t	u16[2];
-		} uip_ip4addr_t;
-		typedef uip_ip4addr_t	uip_ipaddr_t
-	#include "pack_struct_end.h"
+	#ifdef __CC_ARM
+		__packed /* The ARM compiler insists on this being packed, but with other compilers packing it generates a warning as it will be packed anyway. */
+	#endif
+
+	typedef union			uip_ip4addr_t
+	{
+		u8_t	u8[4];	/* Initializer, must come first!!! */
+		u16_t	u16[2];
+	} uip_ip4addr_t;
+	typedef uip_ip4addr_t	uip_ipaddr_t;
 #endif /* UIP_CONF_IPV6 */
 
 /*---------------------------------------------------------------------------*/