Bug#746578: Revised call for votes (was libpam-systemd to flip dependencies - proposal)

[Ian Jackson <ijackson@chiark.greenend.org.uk>]

Josh Triplett writes ("Bug#746578: libpam-systemd to flip dependencies - proposal"):
> On Wed, 5 Nov 2014 11:49:45 +0000 Ian Jackson <ijackson@chiark.greenend.org.uk> wrote:
> > Thanks again to Josh for all his careful and constructive
> > interventions in the discussion.  I'm glad to see that he's now happy
> > with this proposal.
> 
> This proposal doesn't seem to include the change you made in git commit
> 227f496617929c48bfd20a9c96eead8b91ee69b7 to fix a typo I reported in
> item 4:

Bum.

Given that I had already formally made the change, I think my call for
votes should be read as being a CFV on the revised version,
notwithstanding that the resolution text was incorrectly stated in the
CFV email.  For the avoidance of any doubt:


I am calling for votes on the text below:
  Y     (override, swap dependencies, requires >>3:1)
  FD


Ian.

(My previous vote of Y,FD stands.)

===

Rationale (Constitution 6.1(5)):

1. Currently libpam-systemd (which is pulled in by quite a few
   dependency chains) Depends on `systemd-sysv | systemd-shim (>= 8-2)'.

2. The effect of this is that installing some packages which depend
   (directly or indirectly) on libpam-systemd can cause a user's init
   system to be switched to systemd, even on systems where a user has
   deliberately chosen not to use the default init system, and even
   when the switch is unnecessary.

3. Swappping the order of these dependencies would avoid that and has
   no harmful effect:

4. In particular, on systems that already have systemd-sysv installed,
   libpam-systemd will still not pull in systemd-shim, thus minimizing
   the risk of breakage on systemd systems.  However, on systems that
   intentionally do not have systemd-sysv installed, the installation
   of libpam-systemd will then prefer to pull in systemd-shim and keep
   the installed init system rather than switching to systemd-sysv.

Decision (Constitution 6.1(4)):

5. We therefore overrule the decision of the maintainer of
   libpam-systemd binary package.  The Depends entry
      systemd-sysv | systemd-shim (>= 8-2)
   should be replaced by 
      systemd-shim (>= 8-2) | systemd-sysv

6. For the avoidance of doubt, we do not intend to set this specific
   syntax in stone.  For example, if in future libpam-systemd needs to
   depend on a later systemd-shim, or needs a versioned rather than
   unversioned dependency on systemd-sysv, that is fine and would not
   contradict our decision.

Release (Constitution 6.1(5)):

7. Our advice is that this change should be in jessie.  If necessary,
   this view should be conveyed to the Release Team, after the change
   is in unstable, by filing an unblock request in the usual way.

===