diff --git a/libasn1parser/asn1parser.h b/libasn1parser/asn1parser.h
index b4c72f8b244ac1478abeb200aa20220192f2ba45..126057d66ffa46ec2a0f750ce59c559846652f23 100644
--- a/libasn1parser/asn1parser.h
+++ b/libasn1parser/asn1parser.h
@@ -30,6 +30,13 @@
  * specified inside ASN.1 grammar.
  */
 typedef	intmax_t asn1_integer_t;
+#ifdef	PRIdMAX
+#define	PRIdASN	PRIdMAX
+#define	PRIuASN	PRIuMAX
+#else
+#define	PRIdASN	"lld"	/* Or j? */
+#define	PRIuASN	"llu"	/* Or j? */
+#endif
 
 #include <asn1p_list.h>
 #include <asn1p_oid.h>		/* Object identifiers (OIDs) */