Installer should configure Oneiric and Wheezy for multiarch

[geofft]

Once we figure out #931, we're going to want to be installing things like libreadline6:i386 instead of lib32readline6. In order that this work, sources.list needs to read something like

deb [arch=i386,amd64] http://mirrors.mit.edu/ubuntu/ oneiric main restricted universe multiverse

I'm not sure if the Oneiric/Wheezy d-i is going to do this by itself. The fact that  the multiarch spec refers to explicitly enabling the repo implies no.

[jdreed]

Is there a programmatic way to test for multi-arch support in a distro? Or does it involve "lsb_release -sd" and case statements?

[amu]

Good question. Perhaps you could test whether

apt-config shell foo APT::Architectures

produces any output. (Neither checking the availability of multiarch-support nor dpkg --assert-multi-arch will draw the line at the right point on Ubuntu AFAICT, and anyway I gather you are specifically interested in whether APT supports multiple architectures.)

[jdreed]

The multiarch spec says "sources.list entries not annotated with an architecture name will be interpreted as applying to all configured architectures by default", so I don't in fact think we need to do this. Looking at other examples, we'd need to do it, if, say, the repo supported i386, amd64, and m68k, and we only wanted the first two, or something.

[andersk]

The Ubuntu installer configures multiarch for you where appropriate. See /etc/dpkg/dpkg.cfg.d/multiarch on oneiric and precise, or dpkg {--print-architecture|--print-foreign-architectures|--add-architecture|--remove-architecture} on quantal and wheezy. There’s nothing for us to do here.

(Remember kids, debootstrap is not an Ubuntu installer.)

[andersk]

BTW,
Replying to jdreed:

Looking at other examples, we'd need to do it, if, say, the repo supported i386, amd64, and m68k, and we only wanted the first two, or something.

No, it only matters which architectures the system is configured for, not which architectures the repo supports.