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

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

Rich Freeman posted on Tue, 22 Jul 2014 21:15:01 -0400 as excerpted:

> On Tue, Jul 22, 2014 at 4:06 PM, Martin Vaeth <martin@mvath.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).  Portage already allows you to clean a
> package without its reverse deps leading to a system in exactly the
> state you describe.  I believe portage will just try to bring the
> package back at the next emerge @world (or any other set containing the
> reverse dep).

FWIW I tested this with a number of packages just the other day while 
doing an initial test-build of qt:5 and kde:5 from the relevant 
overlays.  Various kde-workspace5/plasma5 packages can't coexist with the 
kde:4 versions, but I didn't want to remove the kde:4 revdeps or set-
elements from my installed sets until I was sure the kde:5 versions 
worked fine.

Apparently the kwin:5 version I was testing doesn't like my radeon turks 
(hd6670 IIRC) hardware their current v3.16-pre kernel drm drivers as once 
I had the whole setup installed and tried to startx with it, kwin ended 
up in a segfault/respawn cycle, so my surgical unmerge of specific kde:4 
packages was just as well, making it relatively easy to simply emerge -k 
@world and get back to a working system from the binpkgs, automatically 
unmerging the kde:5 blockers on the way since I hadn't actually let 
portage put them in @world just yet.

Yes, a simple emerge --deep @world pulls everything missing but needed 
back in, so that bit of portage at least seems to be working just fine.

-- 
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