Bug#621720: is this an apt bug?

[Faheem Mitha <faheem@email.unc.edu>]

Hi David,

Thanks for the clarification. At first sight 621009 doesn't appear to have 
much relation to this bug, but I'll take your word for it.

What is the broken or group here (and how is it broken?), and what is the 
other or group member? I assume these are both versions of the apache 2 
packages? And which invocation does this refer to, the

sudo apt-get install apache2

or the

sudo apt-get purge apache2-utils

? Thanks.

                                                          Regards, Faheem

On Wed, 27 Apr 2011, David Kalnischkies wrote:

> merge 621009 621720
> thanks
>
> On Wed, Apr 27, 2011 at 17:28, Faheem Mitha <faheem@email.unc.edu> wrote:
> > Just wondering if this is an apt bug, and if anyone else can reproduce it.
>
> It is, try:   -o pkgProblemResolver::FixByInstall=0
> which should help. The problem is that APT tries to fix a broken or-group
> by installing another or-group member which somewhere down in the
> dependency line installs again the package which should have been removed.
> A problem in remove requests, but useful in installation and upgrade
> (before someone says: Just disable it in remove requests then:
> what is the type of this request: apt-get purge apt- aptitude+ dpkg+
> and does it change then we say apt-get install instead…
> - and yes, the request itself is insane and will not work)
>
> APT in unstable has a relatively simple fix so it doesn't override user
> requests anymore with automatic changes, but this doesn't help in
> all cases (through in this one i think it should, but haven't tested yet),
> so it generates similar "strange" errors (see merge).
>
> The proper fix is to implement undoing of actions which lead to a dead end -
> or at least that would help in many more cases. The few remaining can be
> fixed by undoing actions which where consequences of now to be removed
> packages as it can happen at the far end of the resolver process.
>
> Especially the last one is unlikely to be implemented soon
> (by me, i will not stop anyone from grabbing source and patch it)
> the first is hopefully wheezy material soon.
>
>
> Best regards
>
> David Kalnischkies