Re: BUG #16329: Valgrind detects an invalid read when building a gist index with buffering - Mailing list pgsql-bugs

From Tom Lane
Subject Re: BUG #16329: Valgrind detects an invalid read when building a gist index with buffering
Date
Msg-id 3990135.1680104273@sss.pgh.pa.us
Whole thread Raw
In response to Re: BUG #16329: Valgrind detects an invalid read when building a gist index with buffering  (Pavel Borisov <pashkin.elfe@gmail.com>)
Responses Re: BUG #16329: Valgrind detects an invalid read when building a gist index with buffering  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-bugs
Pavel Borisov <pashkin.elfe@gmail.com> writes:
> So I think that the patch by Alexander will do the thing. I also added some
> comments to the code and removed extra context reset in gistBuildCallback
> (which is already done level down) to make things clear.

My apologies for having let this slip through the cracks.  I think
I'd wanted to understand why the committed version of the GiST
index tests doesn't expose the problem, and I never got time to
study that.  I still haven't tracked it down, but the proposed patch
seems clearly safe so I've gone ahead and pushed it.

I did use Alexander's original code change that just moved the
totals-incrementing.  It looks to me like gistProcessEmptyingQueue
is not guaranteed to reach the context reset, and I'd rather have
an extra reset than miss one.  (No-op context resets are cheap.)

            regards, tom lane



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