[gentoo-dev] Re: Revisions for USE flag changes

[Duncan <1i5t5.duncan@cox.net>]

Duncan posted on Sun, 13 Aug 2017 02:52:58 +0000 as excerpted:

> Michael Orlitzky posted on Sat, 12 Aug 2017 05:58:41 -0400 as excerpted:
> 
>> On 08/12/2017 04:39 AM, Paweł Hajdan, Jr. wrote:
>> 
>>> There are use-cases for --changed-use / --newuse other than changed
>>> IUSE.
>>> 
>>> I find it useful to easily rebuild affected packages when changing USE
>>> flags in make.conf. If the flags were removed, would we have a good
>>> alternative?
>>> 
>> I simply overlooked the global USE change in make.conf because IMO it's
>> a nonsense operation
> 
> ??
> 
> How so?  Are you arguing that deciding to system-wide switch to/from
> pulseaudio, systemd, or gstreamer is nonsense?
> 
> If so, I suspect many gentooers including myself strongly disagree.  If
> not, I'd be interested in what you propose as an alternative to changing
> the appropriate USE flag systemwide, for what is after all a systemwide
> change.

After thinking about it for a few days, I see some logic to the point... 
in specific use-cases at least.

Not setting global USE flags works reasonably well, provided 
(overlapping):

* You have exactly one profile that makes sense for you, or you 
effectively create your own.

By definition, this means you either agree with or don't care about other 
defaults, likely including openrc instead of systemd (because otherwise 
you won't be able to choose any other profile instead), and either use a 
minor arch (including x86), or use 16-bit only apps, or simply don't care 
about the additional work and build-time that multilib brings.

Without addins, any time you want elements of multiple profiles, say 
plasma, no-multilib, systemd, etc (as here), you need to start setting 
many global flags for the ones you can't choose, either by setting them 
in make.conf, or by creating your own profile to set them.

* You're just fine with the global defaults for anything not in your 
profile, either because you simply don't care, or because you want them 
the default off.

* Any non-profile/non-IUSE-default USE flags you /do/ care about, you 
care about specific packages only.


In the above scenario it does make some sense not to have any USE flags 
set in make.conf.

Of course that's rather the opposite of my policy, which needs multiple 
profiles so must set the non-profile flags in make.conf, which considers 
an unset flag as much a chosen global default as a set flag, and which 
doesn't like profile or IUSE-defaults changing out from under it, so uses 
-* as a USE= prefix in make.conf.  But my case isn't every case, and 
there's certainly a use-case where it does make sense, now that I've 
thought about it.

Thanks for the prod. =:^)

-- 
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