diff --git a/libraries/liblmdb/mdb.c b/libraries/liblmdb/mdb.c
index 4adbf57..1b9e819 100644
--- a/libraries/liblmdb/mdb.c
+++ b/libraries/liblmdb/mdb.c
@@ -1715,7 +1715,7 @@ static void mdb_audit(MDB_txn *txn)
 		}
 	}
 	if (freecount + count + NUM_METAS != txn->mt_next_pgno) {
-		fprintf(stderr, "audit: %lu freecount: %lu count: %lu total: %lu next_pgno: %lu\n",
+		fprintf(stderr, "audit: %"Z"u freecount: %"Z"u count: %"Z"u total: %"Z"u next_pgno: %"Z"u\n",
 			txn->mt_txnid, freecount, count+NUM_METAS,
 			freecount+count+NUM_METAS, txn->mt_next_pgno);
 	}