[gentoo-dev] Re: USE flags dri, cups, pppd

[Duncan]

Ciaran McCreesh posted on Sun, 20 Jan 2013 22:00:20 +0000 as excerpted:

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> On Sun, 20 Jan 2013 16:59:24 -0500 "Rick \"Zero_Chaos\" Farina"
> <zerochaos@g.o> wrote:
>> chithanh, maybe you can explain to everyone why USE=dri is needed for
>> base profile.  You seem to be the most knowledgable here, can you cite
>> a specific example for how/why a non-desktop profile machine would need
>> USE=dri.  I think that the example may make it more obvious to people
>> what is right or wrong here.
>
> Your question is the wrong one to ask. What you should ask is whether a
> non-desktop profile machine *would be in any way affected by* USE=dri.

Exactly so.

equery h -p dri

... returns, with a single exception, only x11-drivers/xf86-video-*  xorg 
graphics driver packages.  The single exception is x11-libs/libvdpau.

So the only way the status of USE=dri even /matters/ is if one of those 
graphics drivers or that vdpau library is installed.  And for those 
packages, USE=+dri is the best default, regardless of whether they're 
installed for some reason on a server, or on a desktop.  Nothing else 
cares.


That said, there IS the argument for eliminating USE flag pollution in 
profiles where they aren't likely to be used in any case.  For the server 
non-X-installed server case, just having the flag there means time out of 
every responsible server admin's life, just to figure out that the flag 
is simply noise they don't have to worry about, and from this point of 
view, shouldn't even be seeing.

I mean, while it's technically true that a USE flag not actually used by 
any packages won't make a difference, that logic, taken to its 
conclusion, would lead to every USE flag ever used by a single package 
showing up in both global USE and in profiles, since the claim is that it 
doesn't make a difference if no installed package uses the flag anyway, 
but we REALLY REALLY need a default, just in case you DO decide to 
install the one obscure package that actually DOES use the flag!


So were we starting fresh, the best case would be to put the dri USE flag 
in the desktop profile, instead of in base, simply to avoid the USE flag 
noise pollution in non-desktop profiles.  However, the argument here is 
that we're not starting fresh, and changing it now could break a lot of 
users.

But I think those supporting that argument may have lost sight of the 
context:  The context is the new 13.0 profiles, and from all I've seen 
(Dale can back me up as he's far more involved on the user lists and 
forums), users switching/upgrading profiles generally /expect/ to have a 
few config changes they might need to deal with.  Thus, while the flag 
arguably shouldn't be changed in the old soon-to-be-deprecated 10.x 
profiles to avoid breaking people, the new 13.0 profiles are a chance to 
cleanup that USE flag pollution -- likely the best chance we're going to 
get for a few years.


So that's what I (and others, but less explicitly) propose, leaving 
USE=dri where it is in the old and soon-to-be-deprecated 10.x profiles so 
nobody gets broken, while in the new 13.0 profiles, USE=dri is moved from 
base to desktop.  That way, it'll still be defaulted on for desktop where 
most people will want it, but won't appear in the new base, thus 
eliminating the pollution for people unlikely to care about it, there.  
And the only possibility for breakage will be with the profile upgrade, 
when people should expect and thus be prepared to deal with a bit of 
config change.

-- 
Duncan - List replies preferred.   No HTML msgs.
"Every nonfree program has a lord, a master --
and if you use the program, he is your master."  Richard Stallman