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From: David Rowley <dgrowleyml@gmail.com>
Date: Mon, 13 Apr 2026 01:34:52 +1200
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Subject: Re: Use stack allocated StringInfoDatas, where possible (round 2)
To: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Cc: pgsql-hackers@lists.postgresql.org
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On Sun, 12 Apr 2026 at 22:49, Bertrand Drouvot
<bertranddrouvot.pg@gmail.com> wrote:
> Indeed, 5509055d6956 added a few cases that are using StringInfo but don't need
> that StringInfo to exist beyond the scope of the function were using makeStringInfo(),
> which allocates both a StringInfoData and the buffer it uses as two separate
> allocations. It's more efficient for these cases to use a StringInfoData on the
> stack and initialize it with initStringInfo(), which only allocates the string
> buffer.

I think the author of copy_sequences() doesn't know what
resetStringInfo() does. I expect they think that it'll pfree all the
memory, but that's what destroyStringInfo() is for.

Since the strings are not used after the resetStringInfo(), the call
is pointless. Could you ask Amit K to fix that first? Then rebase your
patch atop.

I think it makes sense to apply your patch as a StringInfo fixup
post-freeze for v19 as leaving this for v20 will just result in the
code not matching for no particularly good reason.

David