diff --git a/sys/modules/if_ef/Makefile b/sys/modules/if_ef/Makefile
index 1b7d86b6f8a..f3996edb420 100644
--- a/sys/modules/if_ef/Makefile
+++ b/sys/modules/if_ef/Makefile
@@ -13,8 +13,6 @@ ETHER_8023=
 ETHER_8022=
 ETHER_SNAP=
 
-CFLAGS+= ${PROTOS}
-
 .if defined(EFDEBUG)
 CFLAGS+= -DEF_DEBUG
 .endif