diff --git a/src/include/netif/ppp/ppp.h b/src/include/netif/ppp/ppp.h
index a260a318..41efb4b2 100644
--- a/src/include/netif/ppp/ppp.h
+++ b/src/include/netif/ppp/ppp.h
@@ -38,11 +38,11 @@
 #define PPP_H
 
 #include "lwip/def.h"
-#include "lwip/sio.h"
 #include "lwip/stats.h"
 #include "lwip/mem.h"
 #include "lwip/netif.h"
 #include "lwip/sys.h"
+#include "lwip/sio.h"
 #include "lwip/timers.h"
 #if PPP_IPV6_SUPPORT
 #include "lwip/ip6_addr.h"
diff --git a/src/include/netif/ppp/ppp_impl.h b/src/include/netif/ppp/ppp_impl.h
index 20ea9ba7..9e7ab8d5 100644
--- a/src/include/netif/ppp/ppp_impl.h
+++ b/src/include/netif/ppp/ppp_impl.h
@@ -45,7 +45,6 @@
 #include "lwip/netif.h"
 #include "lwip/def.h"
 #include "lwip/timers.h"
-#include "lwip/sio.h"
 
 #include "ppp.h"
 #include "pppdebug.h"
diff --git a/src/netif/slipif.c b/src/netif/slipif.c
index 6a8f4ae9..ca9f0b97 100644
--- a/src/netif/slipif.c
+++ b/src/netif/slipif.c
@@ -64,8 +64,8 @@
 #include "lwip/pbuf.h"
 #include "lwip/stats.h"
 #include "lwip/snmp.h"
-#include "lwip/sio.h"
 #include "lwip/sys.h"
+#include "lwip/sio.h"
 
 #define SLIP_END     0xC0 /* 0300: start and end of every packet */
 #define SLIP_ESC     0xDB /* 0333: escape start (one byte escaped data follows) */