diff --git a/tests/66-ref-simple-OK.asn1.-P b/tests/66-ref-simple-OK.asn1.-P
index 305d724..0259fc0 100644
--- a/tests/66-ref-simple-OK.asn1.-P
+++ b/tests/66-ref-simple-OK.asn1.-P
@@ -130,7 +130,7 @@
 
 asn_dec_rval_t
 SimpleType_decode_ber(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td,
-		void **structure, void *bufptr, size_t size, int tag_mode) {
+		void **structure, const void *bufptr, size_t size, int tag_mode) {
 	SimpleType_1_inherit_TYPE_descriptor(td);
 	return td->ber_decoder(opt_codec_ctx, td, structure, bufptr, size, tag_mode);
 }
@@ -145,7 +145,7 @@
 
 asn_dec_rval_t
 SimpleType_decode_xer(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td,
-		void **structure, const char *opt_mname, void *bufptr, size_t size) {
+		void **structure, const char *opt_mname, const void *bufptr, size_t size) {
 	SimpleType_1_inherit_TYPE_descriptor(td);
 	return td->xer_decoder(opt_codec_ctx, td, structure, opt_mname, bufptr, size);
 }