Andrew Gierth <andrew@tao11.riddles.org.uk> wrote:
> I didn't replace the 0xFFFFFFFF ones because most or all of them looked
> like basically bit-masking operations rather than actually dealing with
> the bounds of an unsigned int or uint32. I was specifically looking for
> places where literals were being used to represent maximum or minimum
> values.
Well, InvalidSerCommitSeqNo was initially defined to be UINT64_MAX
-- but some buildfarm members didn't know about that so it was
changed to UINT64CONST(0xFFFFFFFFFFFFFFFF). It is very much about
wanting the maximum value for uint64. As the comment says:
* - InvalidSerCommitSeqNo is used to indicate a transaction that
* hasn't committed yet, so use a number greater than all valid
* ones to make comparison do the expected thing
It does seem odd to only define *some* of these constants.
--
Kevin Grittner
EDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company