Bug#752989: libio-callback-perl: FTBFS with Perl 5.20: alternative dependencies

[Niko Tyni]

On Sat, Jun 28, 2014 at 02:18:13PM +0200, Jonas Smedegaard wrote:
> Quoting Niko Tyni (2014-06-28 13:44:57)
> > On Sat, Jun 28, 2014 at 09:41:46AM +0200, Jonas Smedegaard wrote:

> >> Relying on a (build-)dependency being resolved by a virtual package 
> >> is not allowed by Policy, with the reasoning that it causes 
> >> non-deterministic behaviour.
> >
> > Which policy clause is that?
> 
> Oh well - I might be wrong and it is "just" an overly strong 
> interpretation by ftpmasters that I have experienced in the past.
> 
> Or perhaps it is not an overly strong interpretation, but a real 
> sensible one which has just not yet been codified in Policy.
> 
> Do you find the reasoning I gave non-sensical?

I don't find it particularly relevant to this case.

I think it's about situations where multiple packages provide the same
virtual package, so dependency resolvers need to pick one at random if
none are installed and there are no hints provided.

In the context of dual lived Perl modules, I think we've been relying
on virtual packages satisfying build dependencies for a long time and
there isn't any non-deterministic behaviour about them.
-- 
Niko Tyni   ntyni at debian.org