pgsql-server: I think I've finally identified the cause of the

Log Message:
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I think I've finally identified the cause of the off-by-one-second
issue in timestamp conversion that we hacked around for so long by
ignoring the seconds field from localtime(). It's simple: you have
to watch out for platform-specific roundoff error when reducing a
possibly-fractional timestamp to integral time_t form. In particular
we should subtract off the already-determined fractional fsec field.
This should be enough to get an exact answer with int64 timestamps;
with float timestamps, throw in a rint() call just to be sure.

Modified Files:
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pgsql-server/src/backend/utils/adt:
timestamp.c (r1.106 -> r1.107)
(http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/backend/utils/adt/timestamp.c.diff?r1=1.106&r2=1.107)