According to the Wiki, the Arch image doesn't use Hard Float support and I'm pretty sure it uses the ARMv5 instruction set. Would it be possible to build a distribution that used Hard Float and ARMv6?
UPDATE: Arch Linux ARM now natively supports
armv6hso will run optimised on the Pi. The rest of this answer still applies to other architectures.
Yes it would be possible, but you would have to recompile every piece of software for ARMv6-hard. Arch have build systems and infrastructure to do this automatically for their supported platforms (ARMv5-soft and ARMv7-hard), so you would need to duplicate this yourself somewhere to build ARMv6-hard versions of everything.
It would be quite possible to do it on a normal desktop PC running Arch, it just takes time to get everything up and running. You would also then need to track package updates and get your build system to pull down new versions and compile them too, so that your software doesn't get out of date.
If you (or anyone) did this, it would be useful to publish the compiled binaries on a public web site somewhere so that other people can use your new flavour of Arch without worrying about compiling it themselves.
If you did want to undertake this, you would need to familiarise yourself with:
- Compiling programs from source
- The Arch Build System (ABS) or the Arch User Repository (AUR)
- Creating custom Pacman repositories
A good place to start would be to pick some packages off AUR and compile them into your own repository, and make sure you can sync it with pacman. Once that's done all you would need to do is adjust the compiler flags (for ARMv6-hard) and then repeat for probably all the packages in the default [core] repo.
You could then tell pacman to reinstall every package on your Pi from your new hardfloat repo instead, reboot, and you'll then be running everything from your own hardfloat packages.