Re: [gentoo-portage-dev] [PATCH] emerge(1): document --oneshot caveats (bug 563482)

[Rob Wortman <wyrm@haell.com>]

On 2015-10-20 at 22:11:24 -0700, zmedico@gentoo.org wrote:
> Any packages that are not reachable from @world are ripe for removal by
> --depclean, so we allow their dependencies to break in order to satisfy
> other dependencies (like in bug 563482). If you don't use --deep, then
> emerge may try to build something that depends on one of these
> unreachable packages with broken dependencies, such that whatever you
> are trying to build has broken indirect dependencies (which is likely to
> trigger a build failure like in bug 563482).

I think I understand. So, one could get the hypothetical scenario:

# emerge --oneshot A # which depends on B
# emerge --update @world # shuffles stuff around breaking B
# emerge C # which depends on A

Package C's dependency is filled, so emerge goes ahead and builds C.
Now, either C fails to build, or it is installed but fails at runtime,
because it depends on a package which depends on a package which is
broken.

Sound about right?

-- 
There are problems in today's world that cannot be
solved by the level of thinking that created them.
  -- Albert Einstein