[buildd-tools-devel] Bug#586275: Bug#586275: sbuild: alternative build-deps and Provides do not work correctly

[Ansgar Burchardt]

Roger Leigh <rleigh at codelibre.net> writes:

> On Fri, Jun 18, 2010 at 11:50:04AM +0900, Ansgar Burchardt wrote:
>> sbuild does not handle alternative dependencies that are also Provided
>> by another package correctly:
>> 
>> libcpan-meta-perl_2.101670-1 has a build-dependency on
>> libversion-perl (>= 1:0.8200) | perl (>= 5.12).  libversion-perl is also
>> provided by perl-modules.
>
> I'm afraid this is a long-standing issue with sbuild.  Alternative
> build-dependencies are just not supported.  You'll see there are
> a number of existing bug reports regarding this issue.
>
> Note that one disadvantage of them is that it can potentially make
> builds non-deterministic, which is probably why not much effort
> went in to making them work.

As far as I know, sbuild's internal resolver tries to satisfy the first
alternative.  But the problem in this case is caused by sbuild trying to
satisfy *both* alternative dependencies instead of ignoring everything
but the first alternative.

sbuild should only install libversion-perl instead of both
libversion-perl and perl 5.12.

Regards,
Ansgar