diff --git a/test/unit/lwipopts.h b/test/unit/lwipopts.h
index 9c105419..5cda4315 100644
--- a/test/unit/lwipopts.h
+++ b/test/unit/lwipopts.h
@@ -34,6 +34,7 @@
 
 /* Prevent having to link sys_arch.c (we don't test the API layers in unit tests) */
 #define NO_SYS                          1
+#define SYS_LIGHTWEIGHT_PROT            0
 #define LWIP_NETCONN                    0
 #define LWIP_SOCKET                     0