Re: [gentoo-user] This nite's switch to "full multilib"

[Alan McKinnon]

On 30/03/2015 12:02, Stefan G. Weichinger wrote:
> On 30.03.2015 11:39, Alan McKinnon wrote:
>> On 30/03/2015 11:23, Mick wrote:
>>> Hmm ... I don't think setting abi_x86_32 globally is necessary, unless you
>>> want to have 32bit libs for ALL packages that these exist for, whether you use
>>> them or not.  I mean that for Skype you have no alternative at present, but if
>>> you don't use Skype then you would not need the 32bit versions of Skype's
>>> dependencies.  If my understanding is wrong, Alan will soon put me right on
>>> this.  :-)
>>
>>
>> You understand it just fine.
>
> OK, then so why do I have to edit files to tell the system to USE this
> and that after the system tells me it needs that ... ?
>
> Why isn't this taken care of within portage itself?
>
> I don't *want* to decide 32bit or not ... (I like that I *can* ...)
>
> I want a (mostly) stable and current linux system with the necessary
> choices done by the maintainers ... if Skype needs it ... ok, then make
> that a dependency/requirement somewhere ... but why force me to set that
> (for so many packages) ?


OK, think it through first.

You want skype. Skype is 32bit. So far, we're good. You put an entry in
package.use to enable abi_x86_32 for skype.

But that's not the end of the story, because *every*single*lib* skype
uses now needs a 32 bit, and the skype ebuild cannot change that. That
part should be obvious - the skype ebuild cannot make changes to how the
qt ebuilds behave, only you can do that. And you do it either with a
global flag or by listing what you want in package.use - none of this
has changed, you've been doing exactly this for years.

The next problem is the sheer number of libs that now have to be tagged
as needing 32 bit versions to be built. It's not like deciding you want
ffmpeg and now a few odd things need to be rebuilt with ffmpeg support;
if you don't rebuild all dep libs with 32 bit versions, then skype does
not work at all.

You've never had to do this before as we had emul-linux-x86 to provide
the needed versions, now we have to do that part ourselves. Ans it's a
long list, no getting around that.

>
> -
>
> I removed the global flag now again and only had to add that flag for a
> few packages now ... maybe because others have been rebuilt already?

Possibly, I'm not sure what steps you already took

>
> Maybe it isn't as bad as I thought in the first place.
>
> I hope that this is a desktop/GUI-issue mostly? Having to do that on
> dozens of customer servers is not on my wishlist right now :-)


Well, there is legacy grub, that's a 32 bit app and needs to be dealt with.

Otherwise in practice it is mostly GUI apps and then mostly only
proprietary bundles (skype, flash, and friends). All the regular open
source apps you run have been fully 64 bit for ages.

It's entirely possible there is some niche app for server situations
that is also 32 bit, but I have not come across any yet.


-- 
Alan McKinnon
alan.mckinnon@×××××.com