[gentoo-user] multilib - do I need it?

[Francisco Ares]

Hi,

How does one know previously which packages will require 32 bit ABI ?

I have two systems (among others) to consider: one is very simple, built using as fewer packages as possible, it is the development system for an embedded equipment, and it is 64 bit ABI only - no multilib;  the other is a general purpose workstation, with lots of packages, and someday, by some forgotten reason, I needed to install emul-linux-* .

Now I'm willing to change the profile to no-multilib, I have found that a lot of packages require to be rebuilt for 32 bit ABI. Is there a way of checking which are the packages requiring 32 bit ABI?

Thanks,

Francisco

[Mick]

Portage should ask you to add the abi_x86_32 in the relevant packages' USE
flags when you run 'emerge @preserve-rebuild -a'

--
Regards,
Mick

[Walter Dnes]

On Thu, Apr 02, 2015 at 02:12:40PM -0300, Francisco Ares wrote

> Hi,
>
> How does one know previously which packages will require 32 bit ABI ?
>
> I have two systems (among others) to consider: one is very simple, built
> using as fewer packages as possible, it is the development system for an
> embedded equipment, and it is 64 bit ABI only - no multilib; the other is
> a general purpose workstation, with lots of packages, and someday, by some
> forgotten reason, I needed to install emul-linux-* .

Can you attach your /var/lib/portage/world file to a post here? I
assume you have nothing embarressing in it. Almost all applications
that used to require 32-bit emulation now run natively on 64-bit
no-multilib. I recently upgraded a 7+ year old machine from 32-bit
Gentoo to 64-bit-only Gentoo (no-multilib) and I don't have any apps
with problems as 64-bit only.

--
Walter Dnes <walt...@waltdnes.org>
I don't run "desktop environments"; I run useful applications

[Peter Humphrey]

On Thursday 02 April 2015 21:30:14 Walter Dnes wrote:

> I recently upgraded a 7+ year old machine from 32-bit Gentoo to 64-bit-
> only Gentoo (no-multilib) and I don't have any apps with problems as 64-
> bit only.

Do you have Flash? If that runs on no-multilib I'd consider switching to
that profile. Don't know about VirtualBox though, which I use for WinXP from
time to time.

Is there a prescribed route to switching profiles like this?

--
Rgds
Peter.

[Walter Dnes]

On Fri, Apr 03, 2015 at 01:44:04AM +0100, Peter Humphrey wrote

> On Thursday 02 April 2015 21:30:14 Walter Dnes wrote:
>
> > I recently upgraded a 7+ year old machine from 32-bit Gentoo to 64-bit-
> > only Gentoo (no-multilib) and I don't have any apps with problems as 64-
> > bit only.
>
> Do you have Flash? If that runs on no-multilib I'd consider switching to
> that profile.

Yes, flash works fine. Mind you, it hogs CPU on my over-7-year-old
Core 2 duo, but the 32-bit version would also do that, too.

> Don't know about VirtualBox though, which I use for WinXP from
> time to time.

Bad news for Virtualbox...

======================================================================

[d531][waltdnes][~] emerge -pv virtualbox

These are the packages that would be merged, in order:

Calculating dependencies... done!

!!! All ebuilds that could satisfy "virtualbox" have been masked.
!!! One of the following masked packages is required to complete your request:
- app-emulation/virtualbox-9999::gentoo (masked by: package.mask, missing keyword)
/usr/portage/profiles/features/64bit-native/package.mask:
# AMD64 Team <am...@gentoo.org>
# Mask packages that rely on amd64 multilib

======================================================================

[Peter Humphrey]

On Friday 03 April 2015 01:30:53 Walter Dnes wrote:

> Bad news for Virtualbox...
>
> ======================================================================
>
> [d531][waltdnes][~] emerge -pv virtualbox
>
> These are the packages that would be merged, in order:
>
> Calculating dependencies... done!
>
> !!! All ebuilds that could satisfy "virtualbox" have been masked.
> !!! One of the following masked packages is required to complete your
> request: - app-emulation/virtualbox-9999::gentoo (masked by:
> package.mask, missing keyword)
> /usr/portage/profiles/features/64bit-native/package.mask:
> # AMD64 Team <am...@gentoo.org>
> # Mask packages that rely on amd64 multilib
>
> ======================================================================

Ah, right. So I'll stick to what I have. Thanks.

--
Rgds
Peter.

[Grant Edwards]

On 2015-04-03, Walter Dnes <walt...@waltdnes.org> wrote:
> On Thu, Apr 02, 2015 at 02:12:40PM -0300, Francisco Ares wrote
>> Hi,
>>
>> How does one know previously which packages will require 32 bit ABI ?
>>
>> I have two systems (among others) to consider: one is very simple, built
>> using as fewer packages as possible, it is the development system for an
>> embedded equipment, and it is 64 bit ABI only - no multilib; the other is
>> a general purpose workstation, with lots of packages, and someday, by some
>> forgotten reason, I needed to install emul-linux-* .
>
> Can you attach your /var/lib/portage/world file to a post here? I
> assume you have nothing embarressing in it. Almost all applications
> that used to require 32-bit emulation now run natively on 64-bit
> no-multilib. I recently upgraded a 7+ year old machine from 32-bit
> Gentoo to 64-bit-only Gentoo (no-multilib) and I don't have any apps
> with problems as 64-bit only.

The only two 32-bit apps I've run into on my various XFCE machines are
grub-legacy (which requires a 32-bit ncurses lib), and acroread (which
requires 100+ 32-bit libraries).

--
Grant

[cov...@ccs.covici.com]

hmmm, I have 7 emul-linux86 packages, but portage did not offer to
replace them when I checked today for a world update -- I didn't want to
remove them manually, I thought it might do more harm than good. I am
not sure whether I need any 32-bit libraries, although I do have
multilib enabled, but I wonder about those emul-linux-x86 packages. Any
way for me to tell what is going on here such as dependencies on 32-bit
libraries?


--
Your life is like a penny. You're going to lose it. The question is:
How do
you spend it?

John Covici
cov...@ccs.covici.com

[Mick]

Try this perhaps:

for EMUL in $(eix -I --only-names emul-linux); do equery depends $EMUL; done

unmerge them and the run 'emerge @preserved-rebuild'. Portage will then tell
you which 32bit packages you will need to add in your package.use file with
the 32 bit ABI flag.

--
Regards,
Mick

[cov...@ccs.covici.com]

hmmm, one of the things dependent on emul-linux thingies is the C
compiler! both 4.8.4 and 4.9, so if I unmerge the emul things, will I
still have a C compiler? Otherwise nvidia-drivers seems to also need
emul-linux and they depend on each other.

[Mick]

I suspect some other 32bit binary package which uses Xorg, requires your
nvidia-drivers to be a of a 32bit flavour.

Not so sure about the C compiler. I seem to recall rebuilding gcc recently,
but can't recall if this was as a result of unmerging all emul-linux.

--
Regards,
Mick

[Peter Humphrey]

On Friday 03 April 2015 14:09:23 cov...@ccs.covici.com wrote:

> hmmm, one of the things dependent on emul-linux thingies is the C
> compiler! both 4.8.4 and 4.9, so if I unmerge the emul things, will I
> still have a C compiler?

What does "emerge -pv gcc" tell you about emul-linux?

--
Rgds
Peter.

[cov...@ccs.covici.com]

It just wants to reinstall gcc 4.9 -- does not even mention 4.8 nor
emul-linux.

[Alan McKinnon]

It's safe to remove emul-linux-x86-* to see what happens next; and
fixing it is trivial. So:

- remove those packages
- fiddle make.conf
- emerge world using -p and inspect the list

If you don;t like what you see, revert your edits and remerge
emul-linux-x86-*. They are binary packages so the emerge is rather
quick. As long as you didn't re-merge anything else in the interim,
nothing will break

--
Alan McKinnon
alan.m...@gmail.com

[cov...@ccs.covici.com]

OK, thanks.