Re: BUG #19484: Segmentation fault triggered by FDW

Etsuro Fujita <etsuro.fujita@gmail.com>

From: Etsuro Fujita <etsuro.fujita@gmail.com>

To: Amit Langote <amitlangote09@gmail.com>

Cc: Matheus Alcantara <matheusssilv97@gmail.com>, Ayush Tiwari <ayushtiwari.slg01@gmail.com>, Rafia Sabih <rafia.pghackers@gmail.com>, 798604270@qq.com, pgsql-bugs@lists.postgresql.org, Amit Langote <amitlan@postgresql.org>

Date: 2026-06-18T10:50:59Z

Lists: pgsql-bugs

Amit-san,

On Thu, Jun 18, 2026 at 6:16 PM Amit Langote <amitlangote09@gmail.com> wrote:
> A small clarification on this one: the patch makes no changes to
> postgres_fdw code, only adds a regression test. The bug, which I
> introduced, is in how nodeModifyTable.c supplies fdw_private from the
> pruned/validated fdwPrivLists in ModifyTableState rather than the
> original list in ModifyTable, so the postgres_fdw side itself is
> unchanged. The substantive change is the executor re-indexing.

Thanks for the clarification!

> Still holding off on committing per our exchange, but no rush given
> you may want to prioritize the v19 open items. Happy to go ahead
> whenever, or wait for your comments.

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

Avoid ABI break in ModifyTableState from the FDW pruning fix
- bba4e095d250 18 (unreleased) landed
Re-index ModifyTable FDW arrays when pruning result relations
- b43f8aa4cb30 19 (unreleased) landed
- 1ef917e3a61a 18 (unreleased) landed
Fix universal builds on MacOS
- 901ed9b352b4 19 (unreleased) cited
Track unpruned relids to avoid processing pruned relations
- cbc127917e04 18.0 cited