diff --git a/arch/arm/src/kinetis/kinetis_enet.c b/arch/arm/src/kinetis/kinetis_enet.c
index 096ff54a3d..025dcc2e64 100644
--- a/arch/arm/src/kinetis/kinetis_enet.c
+++ b/arch/arm/src/kinetis/kinetis_enet.c
@@ -69,7 +69,7 @@
 #if defined(KINETIS_NENET) && KINETIS_NENET > 0
 
 /****************************************************************************
- * Definitions
+ * Pre-processor Definitions
  ****************************************************************************/
 
 /* CONFIG_ENET_NETHIFS determines the number of physical interfaces
diff --git a/net/Makefile b/net/Makefile
index bf88c3ea44..9e403b92be 100644
--- a/net/Makefile
+++ b/net/Makefile
@@ -65,9 +65,6 @@ ifeq ($(CONFIG_NET_SOCKOPTS),y)
 SOCK_CSRCS += setsockopt.c getsockopt.c
 ifneq ($(CONFIG_DISABLE_CLOCK),y)
 SOCK_CSRCS += net_timeo.c net_dsec2timeval.c net_timeval2dsec.c
-ifneq ($(CONFIG_NET_SLIP),y)
-SOCK_CSRCS += net_arptimer.c
-endif
 endif
 endif
 
diff --git a/net/net_internal.h b/net/net_internal.h
index d8691aaeec..9577d2ea3e 100644
--- a/net/net_internal.h
+++ b/net/net_internal.h
@@ -51,7 +51,7 @@
 #include <nuttx/net/uip/uip.h>
 
 /****************************************************************************
- * Definitions
+ * Pre-processor Definitions
  ****************************************************************************/
 
 /* Definitions of 8-bit socket flags */
diff --git a/net/net_sockets.c b/net/net_sockets.c
index ae5463352c..5b3581c863 100644
--- a/net/net_sockets.c
+++ b/net/net_sockets.c
@@ -47,6 +47,7 @@
 #include <errno.h>
 #include <debug.h>
 
+#include <nuttx/net/arp.h>
 #include <nuttx/net/uip/uip.h>
 #include <nuttx/net/net.h>
 #include <nuttx/kmalloc.h>
@@ -55,7 +56,7 @@
 #include "net_internal.h"
 
 /****************************************************************************
- * Definitions
+ * Pre-processor Definitions
  ****************************************************************************/
 
 /****************************************************************************