[OE-core] specific version dependenciews

[Wolfgang Denk]

Dear Richard,

In message <1332203843.9740.76.camel at ted> you wrote:
...
> > Some MACHINEs require a package A (some library), but in specific
> > versions: say machine X needs version A-1.2, while machine Y needs
> > version A-1.5.
> > 
> > Package A itself depends on another package B (another library).
> > 
> > The problem is, that different versions of A require specific versions
> > of B.  For example, to build A-1.2 we must use B-4.5, but to build
> > A-1.5 we must use B-8.2.
> > 
> > I am aware that I can describe the dependencies at the top leven,
> > stating for example that machine X needs A-1.2 and B-4.5, while
> > machine Y needs A-1.5 and B-8.2.
> > 
> > However, this seems clumsy, as the version depency A->B is something
> > that is only defined by the implementation of A, and I would like to
> > keep it encapsulated at this level.
> > 
> > 
> > Is there a clever way to describe such a multi-level dependency chain?
> 
> If you mark A and B as machine specific, the system should be able to
> cope with the problem and set the preferred versions at the machine
> level.

I'm sorry, but I don't understand what you mean.

How do I mark a package as machine specific?

And would setting "the preferred versions at the machine level" not be
exactly what I am trying to avoid?

I don't want to make the machine descriptions aware of any version
dependencies between A and B.  I would like to put this information
into the description of A, so that when a specific version of A gets
built, automatically the matching version of B will be chosen.

Can this be done?

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
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It is easier to change the specification to fit the program than vice
versa.