Bug in autovacuum.c?

Looking over the autovacuum.c code, I see:

/*
* Determine the oldest datfrozenxid/relfrozenxid that we will allow to
* pass without forcing a vacuum. (This limit can be tightened for
* particular tables, but not loosened.)
*/
recentXid = ReadNewTransactionId();
xidForceLimit = recentXid - autovacuum_freeze_max_age;
/* ensure it's a "normal" XID, else TransactionIdPrecedes misbehaves */
if (xidForceLimit < FirstNormalTransactionId)
xidForceLimit -= FirstNormalTransactionId;

This last line doesn't look right to me; should it be:

xidForceLimit = FirstNormalTransactionId;

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com

+ It's impossible for everything to be true. +