diff --git a/wal2json.c b/wal2json.c
index 3624781..be170bf 100644
--- a/wal2json.c
+++ b/wal2json.c
@@ -740,7 +740,7 @@ pg_decode_commit_txn_v1(LogicalDecodingContext *ctx, ReorderBufferTXN *txn,
 		elog(DEBUG2, "txn has catalog changes: yes");
 	else
 		elog(DEBUG2, "txn has catalog changes: no");
-	elog(DEBUG2, "my change counter: %lu ; # of changes: %lu ; # of changes in memory: %lu", data->nr_changes, txn->nentries, txn->nentries_mem);
+	elog(DEBUG2, "my change counter: " UINT64_FORMAT " ; # of changes: " UINT64_FORMAT " ; # of changes in memory: " UINT64_FORMAT, data->nr_changes, txn->nentries, txn->nentries_mem);
 	elog(DEBUG2, "# of subxacts: %d", txn->nsubtxns);
 
 	/* Transaction ends */