diff --git a/src/pk/asn1/der/sequence/der_encode_subject_public_key_info.c b/src/pk/asn1/der/sequence/der_encode_subject_public_key_info.c
index 681a53f..2a73864 100644
--- a/src/pk/asn1/der/sequence/der_encode_subject_public_key_info.c
+++ b/src/pk/asn1/der/sequence/der_encode_subject_public_key_info.c
@@ -50,7 +50,7 @@ int der_encode_subject_public_key_info(unsigned char *out, unsigned long *outlen
    }
 
    LTC_SET_ASN1(alg_id, 0, LTC_ASN1_OBJECT_IDENTIFIER, oid.OID,    oid.OIDlen);
-   LTC_SET_ASN1(alg_id, 1, parameters_type,            parameters, parameters_len);
+   LTC_SET_ASN1(alg_id, 1, (ltc_asn1_type)parameters_type,            parameters, parameters_len);
 
    return der_encode_sequence_multi(out, outlen,
         LTC_ASN1_SEQUENCE, (unsigned long)sizeof(alg_id)/sizeof(alg_id[0]), alg_id,