Bug#687268: perl: breaks debsums during squeeze -> wheezy upgrade

[Niko Tyni]

On Tue, Sep 11, 2012 at 05:20:12AM -0700, Andres Salomon wrote:
> On Tue, 11 Sep 2012 14:03:13 +0300
> Niko Tyni <ntyni at debian.org> wrote:
> 
> > On Tue, Sep 11, 2012 at 03:19:50AM -0700, Andres Salomon wrote:
> > > Package: perl
> > > Version: 5.14.2-12
> > > Severity: critical
> > > 
> > > I kicked off an upgrade of a machine running stable (squeeze) to the
> > > currently frozen testing (wheezy).  During the upgrade, I hit the
> > > following:
> > 
> > It looks to me more like the upgrade is failing first, then debsums
> > is run in the failed state.
> 
> I think you're right.  Running 'apt-get -f install' the first time
> installed wheezy's perl-base, which allowed debsums to function
> properly; however, xserver-xorg-core was still failing to upgrade.  The
> second 'apt-get -f install' run fixed the issue.  I've attached the
> logs from those two calls.

> There are 3 issues that I see here, let me know if you disagree:
> 
> 1) either postinst scripts or debsums should fail gracefully if there's
> a problem that's not a failed hash check (severity: wishlist)

There isn't a postinst script failing here. apt runs debsums from a
post-invoke hook which is a different thing.

I suppose either apt shouldn't run post-invoke hooks for failed upgrades,
or the hook scripts should make some (reasonable) efforts to fail
gracefully when the system is in an inconsistent state.

I agree about the wishlist part.

> 2) perl-base should never get out of sync with
> perl and perl-modules (severity: normal?)

More like wishlist wontfix. The only way to fix this would be
to merge them all into one package, which has other downsides.

There are specific constraints on things like preinst scripts, which
can't rely on the package dependencies being in a working order.
The only packages that must work even in an unconfigured state are the
Essential:yes ones. This includes perl-base but not perl or perl-modules.

> 3) xserver-xorg-core breaks upgrades (severity: critical or grave)

Not critical IMO. Maybe serious, but that's sort of nitpicking.
Failing upgrades are definitely release critical bugs anyway.

Feel free to reassign and possibly clone this, or let me know if you
want me to handle that.
-- 
Niko Tyni   ntyni at debian.org