Subject: Re: BUG #16162: create index using gist_trgm_ops leads to panic
To: Heikki Linnakangas <hlinnaka@iki.fi>, Jeff Janes <jeff.janes@gmail.com>
Cc: Tomas Vondra <tomas.vondra@2ndquadrant.com>, Tom Lane
 <tgl@sss.pgh.pa.us>, kunert@cms.hu-berlin.de,
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From: Alexander Lakhin <exclusion@gmail.com>
Message-ID: <4dc09c87-c10d-801e-830b-ae82de53a4a0@gmail.com>
Date: Mon, 16 Dec 2019 22:00:00 +0300
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Hello Heikki,
16.12.2019 15:02, Heikki Linnakangas wrote:
>
> I added the "stack-downlinkoffnum = InvalidOffsetNumber" to the first
> call on Friday. But the second call needs the same treatment, because
> it's possible that we reuse the same stack on a later call to
> gistfinishsplit(), if a grandchild page is split twice, for the same
> leaf insert. I feel pretty dumb, because I looked at that second call
> on Friday too, thinking if it also needs to reset 'downlinkoffnum',
> but somehow I concluded it does not. Clearly it does, as this test
> case demonstrates.
>
> Fix committed. Thanks again for the report!
I can confirm that now the issue is gone.
Thank you!

Best regards,
Alexander