Re: Segfault when restoring -Fd dump on current HEAD

On 2019-Feb-26, Michael Paquier wrote:

> On Tue, Feb 26, 2019 at 12:16:35AM -0500, Tom Lane wrote:
> > Well, if we didn't want to fix this, a reasonable way to go about
> > it would be to bump the archive version number in pg_dump output,
> > so that old versions would issue a useful complaint instead of crashing.
> > However, I repeat that this patch was sold as a notational improvement,
> > not something that was going to break format compatibility. I think if
> > anyone had mentioned the latter, there would have been push-back against
> > its being committed at all. I am providing such push-back right now,
> > because I don't think we should break file compatibility for this.
>
> While I agree that the patch makes handling of the different fields in
> archive entries cleaner, I agree as well that this is not enough to
> justify a dump version bump.

Yeah, it was a nice thing to have, but I didn't keep in mind that we
ought to be able to provide such upwards compatibility. (Is this
upwards or downwards or backwards or forwards compatibility, now,
actually? I can't quite figure it out which direction it goes.)

> > I think this patch needs to be worked over so that what it writes
> > is exactly what was written before. If the author is unwilling
> > to do that PDQ, it should be reverted.
>
> Works for me. With a quick read of the code, it seems to me that it
> is possible to keep compatibility while keeping the simplifications
> around ArchiveEntry()'s refactoring. Alvaro?

Yeah, let me review the patch Dmitry just sent.

--
Álvaro Herrera https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services