diff --git a/src/include/ipv4/lwip/ip_frag.h b/src/include/ipv4/lwip/ip_frag.h
index e9f0a365..31b40b1c 100644
--- a/src/include/ipv4/lwip/ip_frag.h
+++ b/src/include/ipv4/lwip/ip_frag.h
@@ -33,14 +33,14 @@
 #ifndef __LWIP_IP_FRAG_H__
 #define __LWIP_IP_FRAG_H__
 
-#if (IP_FRAG || IP_REASSEMBLY)
-
 #include "lwip/opt.h"
 #include "lwip/err.h"
 #include "lwip/pbuf.h"
 #include "lwip/netif.h"
 #include "lwip/ip_addr.h"
 
+#if (IP_FRAG || IP_REASSEMBLY)
+
 /* The IP timer interval in milliseconds. */
 #define IP_TMR_INTERVAL 1000