Bug#1018146: correct multiarch for blends stuff?

[Helmut Grohne <helmut@subdivi.de>]

Package: src:debian-edu,blends-dev
User: debian-cross@lists.debian.org
Usertags: cross-satisfiability

debian-edu presently cannot be cross-built from source, because its
dependency on blends-dev is not cross-satisfiable. In general,
Architecture: all packages cannot satisfy cross Build-Depends unless
marked Multi-Arch: foreign (or annotated :native). Before doing the
obvious thing, please let us step back.

debian-edu builds a pile of task packages. I am wondering, why are these
task architecture-dependent? If they were Architecture: all, they would
be irrelevant to cross building and this whole bug would become moot. So
this is a relevant question. I have no answer.

So if the education-* tasks do have to be Arch: any, then they're
relevant to cross building. In that case, understanding their
architecture-dependence is important to understanding whether we can
mark blends-dev Multi-Arch: foreign. Keep in mind that Multi-Arch:
foreign is a promise to downstreams that essentially says: This package
works the same way regardless which architecture you install it for.

I hope you can shed some light on these questions rather than blindly
changing some Multi-Arch fields without understanding what they do.

Thanks in advance

Helmut