[Aptitude-devel] Bug#598485: Bug#598485: aptitude suggests to remove unrelated packages to resolve dependencies

[Daniel Hartwig]

Axel Beckert wrote:
> Version: 0.6.6-1ubuntu1
> [...] we'll try to reproduce the issue with a more recent
> version and with one from Debian, e.g. from Wheezy.
>
> So far I couldn't reproduce this on Wheezy (aptitude 0.6.8.1-2) with a
> minimal setup: debootstrap (actually xen-tools' xen-create-image),
> turning off install Recommends automatically, then "aptitude install
> plasma-netbook kde-plasma-netbook kde-plasma-desktop".
>
> The result was sane and what I would have had expected on our precise
> workstations:

Hi Axel

Your issue is this:

   * Multi-arch update for the problem resolver:
     - handle conflicts without removing all foreign-arch
       packages (Closes: #672340) (LP: #831768)
     - correctly recognise dependencies solved by Multi-Arch:
       foreign packages (LP: #968412)

resolved in 0.6.8.1.

I am fairly sure that Michal's original report is unrelated to this,
but haven't had a chance to properly investigate.  The expected
solution he is after was the third option presented by aptitude:

> The following actions will resolve these dependencies:
>
>      Upgrade the following packages:
> 1)     libdpkg-perl [1.15.8.4 (now, testing) -> 1.15.8.5 (unstable)]

although he skipped over it (presumably without realizing as it does
not explicitly mention that dpkg-dev will still be upgraded).

This is the typical issue of solutions not being ordered in the
expected or obvious way.  It appears that in some situations the
resolver prefers to either remove many packages or ignore the users
request, rather than upgrading two packages to unstable.

> I also already created an state bundle in case that's of help.

No, thanks.

Regards