Subject: Re: bug#32018: Guixsd pull error on very old install

From: Pjotr Prins <[email-masked]>
Date: Fri, 13 Jul 2018 21:12:56 +0200

On Mon, Jul 02, 2018 at 11:39:40AM +0200, Ludovic Courtès wrote:
> Hello,
> 
> swedebugia <[email-masked]> skribis:
> 
> > Trying to get an updated an old GuixSD installation via guix pull on a pre 0.10 GuixSD returned an error message about gexp-modules not found. (details can be provided if asked). 
> 
> Could you post the full backtrace?
> 
> > I suggest we either test pulling from old versions (and fix errors) or make it clear in the manual that pulling from very old GuixSD (older than 0.12?) is not supported.
> 
> Pulling from a very old Guix may not work.  We try hard to keep things
> running, but the old ‘guix pull’ had defects, plus the file
> build-aux/build-self.scm (which ‘guix pull’ runs) might use features not
> found in very old versions.

How about making sure that 'guix pull' works between major releases?
That should be reasonably easy to test.

When there is a disruptive release for guix pull make sure the user
upgrades to the closest previous release first. I.e., multi-step
releases are less fraught with breakage.

That way you get an incremental path to upgrade. And you only need to
test between major releases.

Pj.