32bit environment/packages on amd64 [switching back to 32b]

vladms · Last edited by vladms on Tue Jul 26, 2005 1:36 pm; edited 1 time in total

Hello,

I had just installed a 2004.3 amd64 gentoo on my computer (amd64 3000+). The installation went fine, and after 1.5 days I have a running system.

My problem is with the 32bit packages. I searched the forum but from what I understand if a package is available only for x86 you must do a chroot and add it to some /etc files to install it. Is this true or should I keep diging ?

I agree that for some packages that were meant to work on x86 will not work on amd64 (for example a filesystem module), but it seems to me there are hundreads of applications that work on x86 and are not even marked ~amd64. Wouldn't be possible for portage to install the 32 or the 64 bit version ?

If I will not be able to install as simple as I wish, is there an easy possibility to 'downgrade' to x86 ? (besides saving /usr/portage/distfiles, downloading the livecd and reinstalling everything) ? I really like Gentoo for the easyness of installing everything (not that I can't do it the hard way, but I do not have time). so I won't use amd64, unless I can easy install/run everything - even if they are 3-4 bugs a month ...

Thanks.

crazycat · Posted: Tue Jul 26, 2005 7:54 am Post subject:

You should try to read the technotes on 32bit compatibility. There is no way to downgrade , you will have to recompile your whole system. There is an interesting article on 32bit compatibility,you might find it interesting: http://www.redhat.com/magazine/009jul05/features/multilib/

genneth · Apprentice Joined: 24 Mar 2003 Posts: 152 Location: UK

You should also migrate to 2005.0 profile, which will set up a multilib install for you.
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vladms · Posted: Tue Jul 26, 2005 8:40 am Post subject:

For genneth:

And after I upgrdade to 2005.0 profile will emerge some_package_that_is_availbale_only_for_x86 work without any other configuration ? Isn't 2004.3 multilib ? Right now I use for example opera, which is 32bit application (so I guess I have multilib). But emerge won't emerge something marked only for x86.

For crazycat:

Yes I understand that I will recompile, but in the first install I made some configurations (user, pass, fstab, gdm, etc) and I would want to loose all.

crazycat · Posted: Tue Jul 26, 2005 9:50 am Post subject:

Sure, id' also backup the whole /etc folder. xorg.conf, fstab and co. are the same on 64bit and 32 bit installations.

genneth · Apprentice Joined: 24 Mar 2003 Posts: 152 Location: UK

As I understand it, 2005.0 has more "integrated" multilib support. You will not be able to emerge x86 keyworded packages by default. Portage does not track dependencies across the 64/32 bit divide. The only thing that is shared between the two systems is the kernel, which is 64 bit with 32 bit emulation support. Everything above the kernel, from glibc, must be replicated for both. Certain packages in portage provide both, such as the new glibc ebuilds. Most will only provide 64bit (the arch considered native). Some ebuilds will only provide 32 bit. Portage contains no knowledge of this. The binary packages marked amd64 have had the ebuilds edited so that they DEPEND on the 32 bit userspace packages. If you don't know what you are doing, do not force install a non amd64 keyworded package.
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vladms · Posted: Tue Jul 26, 2005 1:31 pm Post subject:

Thank you all for your answers. I think it would be really usefull for portage to keep track of 32/64 bit packages.

As for me I will not switch to 64b architecture if I can't run easy 32b applications - that's why I switched to gentoo from FC: to be able to install without taking care of a ton of dependencies.

I hope someday something will be done to address this (right now I don't understand to well the portage system, so I don't even now it is possible...).
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Vlad-Mihai Sima

eradicator · Posted: Wed Jul 27, 2005 7:47 pm Post subject:

If something isn't marked for amd64, it might be that it just hasn't been tested and marked yet, so try emerging it anyways and file a bug report about it. The only time it definitely won't work for amd64 if it's marked -amd64! Most 32bit only apps have versions that you can emerge on amd64 as precompiled binaries (openoffice-bin, etc). If you want to compile stuff for yourself, setup a 32bit chroot.
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Gentoo Developer: amd64, sparc, sound, toolchain, accessibility

vladms · Posted: Thu Jul 28, 2005 9:41 am Post subject:

Thanks for the answer.

As I said I want to be able to run/install things easily. I know I can set a chroot but I don't feel it's automated enough. My feeling is that there are other area that are more important to improve than the 64bit support. But still I must better understand gentoo, before I can make suggestions. :wink:

. (now I'm at the second installation, and it took just 2 nights instead of 2 nights and 2 days...

)
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Vlad-Mihai Sima