On Fri, Jul 8, 2011 at 11:57 AM, Tom Lane <t...@sss.pgh.pa.us> wrote: > "Kevin Grittner" <kevin.gritt...@wicourts.gov> writes: >> Tom Lane <t...@sss.pgh.pa.us> wrote: >>> At this point I think the actual choice we'd have is to abandon >>> beta3 and try again next week with a beta4. I'm trying to figure >>> out whether this bug is serious enough to warrant that, but it's >>> not clear to me. > >> I changed the definition to this: > >> #define OLDSERXID_MAX_PAGE (-1) > >> That caused my compiler to report the following warnings: > >> predicate.c: In function *OldSerXidAdd*: >> predicate.c:828: warning: division by zero >> predicate.c:848: warning: division by zero >> predicate.c: In function *OldSerXidGetMinConflictCommitSeqNo*: >> predicate.c:958: warning: division by zero >> predicate.c: In function *CheckPointPredicate*: >> predicate.c:1038: warning: division by zero > >> It's hard to imagine that any compiler would evaluate it to -1 >> instead of the value it's had all along (including beta2) and not >> generate these warnings, too. > > The value of OLDSERXID_ENTRIESPERPAGE includes a sizeof() call, so > every compiler I've ever heard of is going to consider it an unsigned > value, so we should be getting an unsigned comparison in the Min(). > So I think you are right that OLDSERXID_MAX_PAGE should end up with > its old value. Still, it's a bit nervous-making to have such problems > popping up with a patch that went in at the eleventh hour --- and it > was about the least of the last-minute patches for SSI, too. So > color me uncomfortable ...
I agree. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
