[gentoo-dev] Re: don't rely on dynamic deps

[Martin Vaeth]

Rich Freeman <rich0@g.o> wrote:
> On Tue, Jul 22, 2014 at 4:06 PM, Martin Vaeth <martin@×××××.de> wrote:
>> ...but by introducing all the additional complications Ian
>> has mentioned. More precisely: What happens if new dependencies
>> are introduced which are not satisfied?
>> One has to face it: Portage must not just silently "update" the
>> database and thus silently produce a /var/db which does not
>> satisfy its own dependencies...
>
> While this is problematic, I think portage actually can handle this
> (but I haven't tested this recently).

The problem here arises if new dependencies with automatic
subslots (foo/bar:=) are added which are not yet installed:
Portage cannot fill these correctly.

Solving all these difficulties appears harder to me than
implementing dynamic deps correctly.

> I think that allowing devs to instruct portage to update VDB with
> USE/dep/etc changes is potentially less problematic than having
> portage trying to guess what the right thing to do is.

I completely agree. The idea of minor revisions is just one of
several possibilities to achieve this; there are several others
(e.g. another metadata variable describing which versions
can be updated by skipping the prepare/config/compile/merge
phases). The implementation, however, would be rather similar:
Usually you need a new EAPI (or in case of noninvasive change
might discuss whether to change EAPI's retroactively), and
some "reemerging without the time-consuming phases"
must be implemented.