Index: asn1-x509.c
==================================================================
--- asn1-x509.c
+++ asn1-x509.c
@@ -364,11 +364,11 @@
 	*outbuf = '\0';
 	outbuf_s = outbuf;
 
 	offset = 0;
 	while (1) {
-		read_ret = asn1_x509_read_asn1_object(whole_thing.contents + offset, whole_thing.size - offset, &current_set, NULL);
+		read_ret = asn1_x509_read_asn1_object(((unsigned char *) whole_thing.contents) + offset, whole_thing.size - offset, &current_set, NULL);
 		if (read_ret != 0) {
 			break;
 		}
 
 		offset += current_set.size + 2;