Avoid use scoped block variable
Hackorum builds and tests every patch posted to the lists, not only commitfest submissions. This is Hackorum's own CI rather than the PostgreSQL project's, and it is still under testing - please report anything that looks wrong.
You can run a PostgreSQL built from this patch straight from Docker, with no checkout and no build:
docker run --rm -p 5432:5432 ghcr.io/hackorum-dev/postgres-patch:t52851psql -h localhost -U postgresBuilt from patchset v1 (message #1), September 20, 2026 at 09:22 AM.
Every patchset is also pushed to a branch of our PostgreSQL fork, so you can check out the same tree CI built. Without a PostgreSQL checkout:
git clone --branch t52851_1 https://github.com/hackorum-dev/postgres.gitIn a checkout you already have, add the fork once:
git remote add hackorum https://github.com/hackorum-dev/postgres.gitthen, for this patchset and every later one:
git fetch hackorum t52851_1 && git checkout t52851_1Patchset v1 (message #1) is on t52851_1
Hi.
I noticed a possible violation of C rules.
Some functions rely on local block variables,
but this are a mistake.
Once that block exits, the memory of the variable is released.
Fix by moving the declaration variables.
best regards,
Ranier Vilela
Attachments:
t52851_1avoid-use-scoped-block-variable-lockfuncs.patchapplication/octet-stream; name=avoid-use-scoped-block-variable-lockfuncs.patchDownload+1-4
avoid-use-scoped-block-variable-rawpage.patchapplication/octet-stream; name=avoid-use-scoped-block-variable-rawpage.patchDownload+1-2
avoid-use-scoped-block-variable-walsender.patchapplication/octet-stream; name=avoid-use-scoped-block-variable-walsender.patchDownload+1-2
Hi,
On 2025-12-09 13:06:35 -0300, Ranier Vilela wrote:
I noticed a possible violation of C rules.
Some functions rely on local block variables,
but this are a mistake.
Once that block exits, the memory of the variable is released.
CStringGetTextDatum() copies its input to a fresh allocation. So there's no
longer-lived references to the local memory, unless I miss something?
Greetings,
Andres Freund
On 12/9/25 17:06, Ranier Vilela wrote:
Hi.
I noticed a possible violation of C rules.
Some functions rely on local block variables,
but this are a mistake.
Once that block exits, the memory of the variable is released.Fix by moving the declaration variables.
When you say "possible violation", did you check the issue is real?
All these places call CStringGetTextDatum, which calls cstring_to_text,
which allocates a new varlena copy of the string. So why is this an
issue, exactly?
regards
--
Tomas Vondra
Em ter., 9 de dez. de 2025 às 13:19, Andres Freund <andres@anarazel.de>
escreveu:
Hi,
On 2025-12-09 13:06:35 -0300, Ranier Vilela wrote:
I noticed a possible violation of C rules.
Some functions rely on local block variables,
but this are a mistake.
Once that block exits, the memory of the variable is released.CStringGetTextDatum() copies its input to a fresh allocation. So there's no
longer-lived references to the local memory, unless I miss something?
Yeah. My bad.
cstring_to_text use palloc.
Sorry for the noise.
best regards,
Ranier Vilela