public inbox for [email protected]  

help / color / mirror / Atom feed

From: Andres Freund <[email protected]>
To: Tom Lane <[email protected]>
Cc: Peter Eisentraut <[email protected]>
Cc: David Rowley <[email protected]>
Cc: pgsql-hackers <[email protected]>
Subject: Re: automatically generating node support functions
Date: Mon, 11 Jul 2022 11:29:15 -0700
Message-ID: <[email protected]> (raw)
In-Reply-To: <[email protected]>
References: <b9acf63c-6693-d87c-f010-ca8ad502a39f@enterp! risedb.com>
	<[email protected]>
	<611d2e! [email protected]>
	<[email protected]>
	<[email protected]>
	<[email protected]>
	<[email protected]>
	<[email protected]>
	<[email protected]>
	<[email protected]>

Hi,

On 2022-07-11 13:57:38 -0400, Tom Lane wrote:
> More generally, I'm having second thoughts about the wisdom of
> auto-generating the NodeTag enum at all.  With the current setup,
> I am absolutely petrified about the risk of silent ABI breakage
> thanks to the enum order changing.  In particular, if the meson
> build fails to use the same input-file order as the makefile build,
> then we will get different enum orders from the two builds, causing
> an ABI discrepancy that nobody would notice until we had catastrophic
> extension-compatibility issues in the field.

Ugh, yes. And it already exists due to Solution.pm, although that's perhaps
less likely to be encountered "in the wild".

Additionally, I think we've had to add tags to the enum in minor releases
before and I'm afraid this now would end up looking even more awkward?


> Of course, sorting the tags by name is a simple way to fix that.
> But I'm not sure I want to buy into being forced to do it like that,
> because of the switch-density question.
> 
> So at this point I'm rather attracted to the idea of reverting to
> a manually-maintained NodeTag enum.

+0.5 - there might be a better solution to this, but I'm not immediately
seeing it.

Greetings,

Andres Freund

view thread (80+ messages)  latest in thread

reply

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Reply to all the recipients using the --to and --cc options:
  reply via email

  To: [email protected]
  Cc: [email protected], [email protected], [email protected], [email protected]
  Subject: Re: automatically generating node support functions
  In-Reply-To: <[email protected]>

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

This inbox is served by agora; see mirroring instructions
for how to clone and mirror all data and code used for this inbox