Re: [gentoo-user] cross-compile attempt

[Peter Humphrey <peter@prh.myzen.co.uk>]

On Monday 01 Aug 2016 14:51:02 Mick wrote:

> Given Andrew's steer I had another look and found this guide:
> 
> https://wiki.gentoo.org/wiki/Project:AMD64/32-bit_Chroot_Guide
> 
> Is this approach still valid, or have things moved on since this article
> was authored (2012) and different configuration/approach is now
> recommended?

I use that method to maintain a 32-bit Atom box. I export its /usr/portage
via NFS to a chroot on this i7 box and build packages in the chroot. Then I
install from packages on the Atom.

I'm sure it would be just as easy, or more so, to mount the whole Atom file
system and work in it as though I had an i7 processor on the Atom file
system. I may try that again. Meanwhile, here's my /etc/init.d/atom script.
The mtab I copy in contains enough entries to forestall error messages:

$ cat /etc/init.d/atom
#!/sbin/openrc-run
depend() {
   need localmount
   need bootmisc
}
start() {
    ebegin "Mounting 32-bit chroot dirs under /mnt/atom"
    mount -t proc /proc /mnt/atom/proc
    mount --rbind /dev /mnt/atom/dev
    mount --rbind /sys /mnt/atom/sys
    mount --rbind /var/tmp/portage /mnt/atom/var/tmp/portage
    mount -t nfs 192.168.1.2:/usr/portage/packages /mnt/atom/usr/portage/packages
    cp /etc/mtab.atom /mnt/atom/etc/mtab
    eend $? "Error mounting 32-bit chroot directories"
}
stop() {
    ebegin "Unmounting 32-bit /mnt/atom chroot dirs"
    rm /mnt/atom/etc/mtab
    umount -f /mnt/atom/var/tmp/portage
    umount -f /mnt/atom/sys/firmware/efi/efivars
    umount -f /mnt/atom/sys/fs/pstore
    umount -f /mnt/atom/sys/fs/cgroup/openrc
    umount -f /mnt/atom/sys/fs/cgroup/cpuset
    umount -f /mnt/atom/sys/fs/cgroup/cpu
    umount -f /mnt/atom/sys/fs/cgroup/cpuacct
    umount -f /mnt/atom/sys/fs/cgroup/freezer
    umount -f /mnt/atom/sys/fs/cgroup
    umount -f /mnt/atom/sys/kernel/config
    umount -f /mnt/atom/sys/kernel/debug
    umount -f /mnt/atom/dev/pts
    umount -f /mnt/atom/dev/shm
    umount -f /mnt/atom/dev/mqueue
    umount -f /mnt/atom/proc
    umount -f /mnt/atom/sys
    umount -f /mnt/atom/dev
    umount -f /mnt/atom/usr/portage/packages
    eend $? "Error unmounting 32-bit chroot directories"
}

Of course I haven't bothered with idiot-proofing it, as I'm the only one
here.

HTH.

-- 
Rgds
Peter