diff --git a/ctaocrypt/src/asn.c b/ctaocrypt/src/asn.c
index 16cbcd76b..72dee4f9f 100644
--- a/ctaocrypt/src/asn.c
+++ b/ctaocrypt/src/asn.c
@@ -71,10 +71,10 @@
 
 
 #ifndef TRUE
-enum {
-    FALSE = 0,
-    TRUE  = 1
-};
+    #define TRUE  1
+#endif
+#ifndef FALSE
+    #define FALSE 0
 #endif