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

[Alan McKinnon <alan.mckinnon@gmail.com>]

On 03/04/2015 18:48, covici@ccs.covici.com wrote:
> Grant Edwards <grant.b.edwards@gmail.com> wrote:
> 
>> On 2015-04-03, Walter Dnes <waltdnes@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).
> 
> 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?

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.mckinnon@gmail.com