We cannot always know which source package to build to satisfy a given dependency (was: Re: Computing Build-Depends at build time (and other updates to debian/control)?)

[Ian Jackson <ijackson@chiark.greenend.org.uk>]

Johannes Schauer writes ("We cannot always know which source package to build to satisfy a given dependency (was: Re: Computing Build-Depends at build time (and other updates to debian/control)?)"):
> since you are talking about computing build orders and avoiding
> having to pre-build every source package, I have bad news for you.
> It is currently already impossible to know which source package to
> build to satisfy a given dependency if that source package hasn't
> been built before for the architecture that you are building for.
> 
> This is not only because source package metadata does not tell you:

Thanks for the info.  I'm sure all of this is very annoying.

But, do you think that my original point, which is that this pre-build
requirement would make matters worse, is right ?

ISTM from a quick read of the wiki page you mention that most of these
problems might be solved or mitigated by relatively small (but perhaps
broad) changes to our existing practices, or by use of new features
like build profiles.  (Of course I don't mean that the work to agree
and implement such changes is trivial.)

Regards,
Ian.