On Fri, 23 Mar 2018 11:53:40 +0100
Ulrich Mueller <ulm@gentoo.org> wrote:

> Still, masking is the wrong way to express such preferences. If you
> package.mask sys-devel/gcc then you say that something is wrong with
> that package. Which I believe is not what you want to express here.

I might have a better usecase for adding masks from overlays.

But its more for the usecase of "there isn't something wrong with that
package", but the more frequent usecase of "Portage is stupid and so we
have masks to coerce the right behaviour"

For example, if I had an overlay that's sole purpose was to
test/transition experimental versions of Perl, where the presumption
was that by installing said overlay, that you wished to upgrade to that
version of Perl, it might make sense to employ masks to prevent portage
doing dumb things.

And by "Dumb things", I mean some of the common problems I see where
portage tries to solve a blocker by downgrading Perl....

Its much simpler to just author a blacklist of "Look, these are things
that are known to be a mess, don't even consider installing them, with
a nice description of why this is nonsense"

Trying to achieve it by any other means simply tempts the problem to
reappear in another form, because everything *other* than package.mask
will have portage try to flip the USE flag to try to make it work, and
end up with people needing --backtrack=1000 and having it still not
work.

package.mask is at least a "look, we know this is nonsense, don't even
explore this line of reasoning" blunt instrument.