Horton

Re: pg_trgm comparison bug on cross-architecture replication due to different char implementation

Noah Misch <noah@leadboat.com>

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From: Noah Misch <noah@leadboat.com>
To: Masahiko Sawada <sawada.mshk@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Joe Conway <mail@joeconway.com>, Peter Eisentraut <peter@eisentraut.org>, Alexander Korotkov <aekorotkov@gmail.com>, "Guo, Adam" <adamguo@amazon.com>, "pgsql-hackers@lists.postgresql.org" <pgsql-hackers@lists.postgresql.org>, Nathan Bossart <nathandbossart@gmail.com>, Jim Mlodgenski <jimmy76@gmail.com>
Date: 2025-02-20T22:07:54Z
Lists: pgsql-hackers 
On Wed, Feb 19, 2025 at 10:48:29AM -0800, Masahiko Sawada wrote:
> Thank you for reviewing the patches. I've fixed these issues and
> attached the updated patches.

Looks good.

> I have one question about the 0001 patch; since we add
> 'default_char_signedness' field to ControlFileData do we need to bump
> PG_CONTROL_VERSION? We have comments about bumping PG_CONTROL_VERSION
> when changing CheckPoint struct or DBState enum so it seems likely but
> I'd like to confirm just in case that we need to bump
> PG_CONTROL_VERSION also when changing ControlFileData.

Yes.  (I'm not aware of value we get from having distinct control file version
and catalog version, but we do have both.)

> If we need, can
> we bump it to 1800? or 1701?

I'd do 1800.  The pattern seems to be to bump to 1800 for the first pg_control
change of the v18 cycle, then 1801, then 1802 for the third change of the
cycle.  That's based on this history:

git log -U0 -p src/include/catalog/pg_control.h | grep -E '^(Date|\+#define PG_CONTROL_VERSION)'

Commits

  1. pg_upgrade: Check for the expected error message in TAP tests.

  2. Fix a typo in 005_char_signedness.pl test.

  3. Add test 005_char_signedness.pl to meson.build.

  4. Fix an issue with index scan using pg_trgm due to char signedness on different architectures.

  5. pg_upgrade: Add --set-char-signedness to set the default char signedness of new cluster.

  6. pg_upgrade: Preserve default char signedness value from old cluster.

  7. pg_resetwal: Add --char-signedness option to change the default char signedness.

  8. Add default_char_signedness field to ControlFileData.

  9. Remove unneeded nbtree array preprocessing assert.