constness fixes, round-trip and fuzz-testing for CHOICE
diff --git a/skeletons/asn_codecs.h b/skeletons/asn_codecs.h
index 4b2a294..e75c270 100644
--- a/skeletons/asn_codecs.h
+++ b/skeletons/asn_codecs.h
@@ -1,6 +1,5 @@
-/*-
- * Copyright (c) 2003, 2004, 2005 Lev Walkin <vlm@lionet.info>.
- * All rights reserved.
+/*
+ * Copyright (c) 2003-2017 Lev Walkin <vlm@lionet.info>. All rights reserved.
  * Redistribution and modifications are permitted subject to BSD license.
  */
 #ifndef	ASN_CODECS_H
@@ -52,10 +51,10 @@
 	 */
 
 	/* Type which cannot be encoded */
-	struct asn_TYPE_descriptor_s *failed_type;
+	const struct asn_TYPE_descriptor_s *failed_type;
 
 	/* Pointer to the structure of that type */
-	void *structure_ptr;
+	const void *structure_ptr;
 } asn_enc_rval_t;
 #define	ASN__ENCODE_FAILED do {					\
 	asn_enc_rval_t tmp_error;				\