diff --git a/src/include/lwip/sockets.h b/src/include/lwip/sockets.h
index 12046643..185beee2 100644
--- a/src/include/lwip/sockets.h
+++ b/src/include/lwip/sockets.h
@@ -58,7 +58,7 @@ struct sockaddr {
 };
 
 #ifndef socklen_t
-#  define socklen_t int
+#  define socklen_t u32_t
 #endif