[fedora-arm] Mandriva and Unity Linux work on armv7 port

[Jon Masters]

On Sat, 2011-07-30 at 00:37 -0300, Paulo César Pereira de Andrade wrote:

>   I did not do any performance measures so far, so
> forgive me if the extra "vmov d#, r#,r#" or "vmov r#,r#, d#"
> is too costly, but I think it should be worth the
> compatibility with rpms for armv5 or earlier. It should
> have been already discussed at fedora, but I really
> do not know the real reason :-)

>   But have already rebuilt some of the "bootstrap" mandriva
> packages, rpm5, etc, as well as have packages built for
> armv5 installed. This way, rebuilding for armv7 is an
> "optimization", and have something to start with...

If you're arguing that one could build support for soft float and have
hard float as an option, I must point out that the reason we're doing
things as we are is that the hard floating point requirement forms part
of an ABI switch that we are making concurrent with the bringup. The
newer ABI is intentionally incompatible, but can be thought of as an
architecture revision since we're requiring v7+ at the same time.

We don't have years of ARM backward compatibility to worry about, so now
is the time to move to the newer ABI, which everyone else is moving to
at the same time. Once we're super successful and famous, and a primary
architecture with millions of users, then we can worry about any changes
we might make in the future. At this stage Fedora ARM doesn't have the
history to justify putting off making a switch, and we'll keep a v5
build of the packages around for those who want that longer term.

Jon.