Re: BUG #18055: logical decoding core on AllocateSnapshotBuilder() - Mailing list pgsql-bugs

Hi,

On 2023-08-21 21:41:46 +0900, Masahiko Sawada wrote:
> On Mon, Aug 21, 2023 at 6:05 AM Andres Freund <andres@anarazel.de> wrote:
> >
> > Hi,
> >
> >
> > I think the real problem is that 272248a0c added InitialRunningXacts a global
> > variable. If it just lived in in struct SnapBuild, this whole thing wouldn't
> > be an issue? The commit justified this choice with avoiding an ABI breakage -
> > but isn't that bogus? The struct is private to snapbuild.c. It doesn't live on
> > disk (that's SnapBuildOnDisk).
> 
> No, since SnapBuildOnDisk contains SnapBuild, if we add something to
> SnapBuild, the on-disk format compatibility would break. See:

Err, yes. That was a brainfart on my part. But we could still just have
handled that via the 'version' field.

Greetings,

Andres Freund