Re: cross builds don't just require alternate b-d's, but additional ones too
+++ Colin Watson [2012-12-09 14:05 +0000]:
> On Sun, Dec 09, 2012 at 01:36:35PM +0100, Matthias Klose wrote:
> > For toolchain packages like gcc-4.7, you can't deduce the build dependencies
> > automatically. Cross building the gcc-4.7 package (not building the cross
> > compiler) requires additional build dependencies, which for a native build are
> > used from the current build. These are:
> > If these should not be hard-coded in the build tools, then we do need some
> > syntax for the control file to specify these cross build dependencies, best in a
> > way which is independent of the target architecture.
> I think that's covered by something along the lines of Guillem's
> profiles proposal, which would allow such things to be annotated with
Yes. I've done a couple of these in my test ubuntu-bootstrap repo and
it works. And it allows package maintainers to do whatever is needed,
so is flexible.
The disadvantage is that in general package maintainers are clueless
about this and in general would prefer some tool that 'knows about
cross building' to do the automatic mappings which will usually work.
I started a mail about this at the weekend to try and clarify my
thinking on this subject but have not yet reached a proposal I am
> I'd still like to be able to deduce as much as possible
> automatically, though, because given the relatively small number of
> people who care about cross-building it takes a very long time to
> annotate lots of packages manually; the more we can do automatically the
yes. I don't really like the idea of doing this in sbuild, but
pragmatically it'll probably work quite well and not get in other
people's way. I would like to have a more general and convincing
long-term plan. I'll carry on trying to work that up. It is a
good subject for a 'cross-build sprint'.
Principal hats: Linaro, Emdebian, Wookware, Balloonboard, ARM