Bug#385670: apt is calculation wrong dependencies

[Goswin von Brederlow <brederlo@informatik.uni-tuebingen.de>]

Michael Vogt <mvo@debian.org> writes:

> On Sat, Sep 02, 2006 at 04:18:18AM +0200, Daniel Leidert wrote:
>> Package: apt
>> Version: 0.6.45
>> Severity: minor
>
> Thanks for your bugreport.
>  
>> Sometimes apt wants to install apache2-mpm-prefork libapache2-mod-php4
>> for me, when I update the system. But there is really no need to do this
>> and after the upgrade I normally have to run 'apt-get remove --purge
>> ...' for these two packages to remove them again. See e.g. today:
> [..]
>
> If that happens again for you, can you please run:
> # apt-get dist-upgrade -u -o Debug::pkgProblemResolver=true -o Debug::pkgDepCache::AutoInstall=true
>
> and attach the result to this bugreport?
>
> Thanks,
>  Michael

This happens (from experience, not from reading the code) if some
package depends 'apache2-mpm-prefork | foobar (>= 1.2-4)' and you have
only foobar 1.2-3 installed. To solve the dependency apt-get decides
to install the first alternative and ignores the fact that foobar will
be updated to 1.2-4 along the way too.

I had the problem with xemacs-mule | xeamcs-nomule all the time.

If you 'apt-get update && apt-get upgrade && apt-get dist-upgrade' the
problem usualy goes away as upgrade does not install new packages.

MfG
        Goswin