Re: [gentoo-dev] Adding USE=udev to linux profiles

[Dennis Schridde]

Am Dienstag, 24. Juli 2018, 19:15:19 CEST schrieb Ian Stakenvicius:
> On 2018-07-21 9:33 a.m., Rich Freeman wrote:
> > On Sat, Jul 21, 2018 at 5:33 AM Zac Medico <zmedico@g.o> wrote:
> >> Sure, why not? So ^flag would mean that the flag state propagates from
> >> the settings in IUSE.
> >
> > Presumably this could be overridden in subsequent profiles, or
> > /etc/portage.  That is, one profile might set a flag, and another
> > profile could unset it, and then the final one could re-set it.
> >
> >> It's also conceivable that we could add a way for
> >> profiles to modify the effective IUSE defaults, via new operators in
> >> package.use or by introducing a new file such as package.use.default.
> >
> > That makes sense, or the syntax could be available in the ebuild.  I
> > imagine the better approach to take would depend on the nature of the
> > incompatibility.
>
> This is getting a little scary as to what is overriding what, within a
> repo.

I also tried to untangle this in my email from Sat, 21 Jul 2018 14:45:12 +0000

It indeed is a bit confusing, but I think you got it right in your list below:

> Lets take a look at what we -can- do right now:
>
> (a) use flag can be set globally by the repo
> (b) ebuild IUSE can set (and unset?) a flag's state
> (c) make.defaults and package.use from the profile (that generally is
> defined within the gentoo repo) sets/unsets a flag's state
> (d) make.conf sets/unsets a flag's state
> (e) /etc/portage/package.use sets/unsets a flag's state
> (f) {,package.}use.{mask,force} from the profile overrides a-e
> (g) /etc/portage/profile/{,package.}use.{mask,force} overrides f
>
> That's a lot of possible state overriding.

I, too, would hope that at some point later, independently of this discussion, 
the algorithm for determining what use flags are active for a certain package 
could be simplified.

--Dennis