Re: BUG #17406: Segmentation fault on GiST index after 14.2 upgrade

>
> I got approval to send a table with its data and index in the subject
> datafile.
> Taken from the v14 database.
> 

Thanks for the data! I've been able to reproduce the issue (load into
12, pg_upgrade to 14 and run the query). After bisecting this for a
while, this seems like a bug in PG13 commit

commit 911e70207703799605f5a0e8aad9f06cff067c63 (HEAD)
Author: Alexander Korotkov <akorotkov@postgresql.org>
Date:   Mon Mar 30 19:17:11 2020 +0300

    Implement operator class parameters

    ...

It works fine when upgrading to an earlier build, and crashes since this
commit. I haven't investigated this further, but I guess there's some
thinko in gist_ltree_ops, affecting how we interpret existing indexes.

Alexander, any ideas?


regards

-- 
Tomas Vondra
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