Re: amd64 as default architecture
On 2012-06-01 11:54 +0200, Goswin von Brederlow wrote:
> Guillem Jover <email@example.com> writes:
>> On Sun, 2012-05-20 at 14:03:35 +0200, David Kalnischkies wrote:
>>> On Sun, May 20, 2012 at 1:10 PM, Sven Joachim <firstname.lastname@example.org> wrote:
>>> > On 2012-05-20 11:27 +0200, Goswin von Brederlow wrote:
>>> > > Slightly OT but I wanted to mention it for its similarity:
>>> > >
>>> > > One thing that should be tested and then documented prominently as yay
>>> > > or nay in the wheezy upgrade notes is wether one can cross-grade from
>>> > > i386 to amd64 using multiarch. Wether one can install apt/dpkg:amd64 and
>>> > > then migrate to a 64bit userspace.
>>> > Won't work in wheezy, apt does not support crossgradesà¸™.
> Why? What breaks?
You give the answer yourself:
> Testing (see below) shows that there is one big issue, namely that
> crossgrading wants to remove the package before installing the new
This means you have to crossgrade at least the essential packages
without apt's help. While this should not pose insurmountable
difficulties, it is probably not something to be recommended to the
> Interestingly enough apt has no problem with removing an essential
> package from a foreign architecture. In this case though it breaks
> because the diversion handling in bash/dash is broken for crossgrades:
> Removing dash ...
> Removing 'diversion of /bin/sh to /bin/sh.distrib by dash'
> dpkg-divert: error: rename involves overwriting `/bin/sh' with
> different file `/bin/sh.distrib', not allowed
> dpkg: error processing dash (--remove):
> subprocess installed pre-removal script returned error exit status 2
This may be a bug in dash. Few people remove essential packages, so
removing dash has probably not been tested so well.
> Overall the one MAJOR showstopped seems to be that apt/dpkg can't
> crossgrade a package without removing it.
Only apt cannot do that, dpkg has no problem with it. But if you use
dpkg alone you may be left with lots of unfulfilled dependencies after
the crossgrade, see #20471¹.