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Wheeler" In-Reply-To: <2638276.1731717056@sss.pgh.pa.us> Date: Sat, 16 Nov 2024 11:04:40 -0500 Cc: Noah Misch , Aleksander Alekseev , pgsql-hackers , Marco Slot , Alvaro Herrera , Christoph Berg , Pavan Deolasee Content-Transfer-Encoding: quoted-printable Message-Id: References: <1976928.1731614974@sss.pgh.pa.us> <202411142033.u6za5a6ylj2k@alvherre.pgsql> <20241114224108.d0.nmisch@google.com> <2443809.1731683394@sss.pgh.pa.us> <20241115175223.68.nmisch@google.com> <2483970.1731702561@sss.pgh.pa.us> <2500050.1731705196@sss.pgh.pa.us> <900DE0C9-48C4-474C-BDC9-AD495D8D3F59@justatheory.com> <2638276.1731717056@sss.pgh.pa.us> To: Tom Lane X-Mailer: Apple Mail (2.3826.200.121) List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk On Nov 15, 2024, at 19:30, Tom Lane wrote: > That text says exactly nothing about what specific code changes to > make or not make. I'm not sure offhand where (or if) we have this > documented, but there's an idea that adding fields at the end of > a struct is safer ABI-wise than putting them in the middle. Which > is true if you can't squeeze them into padding space. Here, that > could have been done and probably should have. >=20 > The other bit of documentation we probably need is some annotation in > struct ResultRelInfo saying "do not change the sizeof() this struct > in back branches, period=E2=80=9D. This sounds like complementary documentation for committers; totally = agree the guidance should be written down somewhere. D