diff --git a/library/des.c b/library/des.c
index b8bb271..6d20758 100644
--- a/library/des.c
+++ b/library/des.c
@@ -1012,6 +1012,6 @@
     return( 0 );
 }
 
-#endif
+#endif /* POLARSSL_SELF_TEST */
 
-#endif
+#endif /* POLARSSL_DES_C */