pg_upgrade: Add checksum C comment

We might eventually allow checksum to no-checksum upgrades.

diff --git a/contrib/pg_upgrade/controldata.c b/contrib/pg_upgrade/controldata.c
index 41a8c694e7a77076cf5ac669d9d08179457b964a..e9376e207f434330aeb80e59634f7bf64a81dc7e 100644 (file)
--- a/contrib/pg_upgrade/controldata.c
+++ b/contrib/pg_upgrade/controldata.c
@@ -621,6 +621,7 @@ check_control_data(ControlData *oldctrl,
                           "options.\n");
        }
 
+       /* We might eventually allow upgrades from checksum to no-checksum clusters. */
        if (oldctrl->data_checksums != newctrl->data_checksums)
        {
                pg_log(PG_FATAL,