On Mon, 13 Jan 2014 18:03:31 +0100
Luis Ressel <aranea@aixah.de> wrote:

> No, the problem wasn't that rebuilds weren't done (btw: this is not
> about @preserved-rebuilds, but about subslot dependencies), but that
> updates which would trigger such rebuilds are silently ignored. This
> happened to me yesterday while trying --backtrack=0. The available
> update to dev-haskell/parsec simply didn't show up (haskell ebuilds
> make heavy use of subslot deps), I only noticed this because I knew
> there was in fact an update available (thanks to eix-diff). Only after
> enabling backtracking Portage found the update.
> 
> This might well be a bug, perhaps I'll examine the situation when I've
> got more time. 

That description is broad, it sounds like you didn't pass -uD to emerge;
if it is part of the dependency graph (it should, otherwise this
discussion would be useless) and is an update (it is, due to eix-diff),
then with -uD it would pull that in.

This even doesn't have to do anything with sub-slot dependencies as far
as I know; because why would it check the sub-slot dependencies if it
were an upgrade, the upgrade takes precedence over the sub-slot
dependencies. The other option is that I am confused about this; as you
can see, given the possible scenarios that could happen I might have a
different one on mind than you do.

If backtracking doesn't get to it, it would have to list it as a
conflict; if it doesn't do that at the moment, then we certainly have a
bug somewhere I think. Thank you in advance for investigating this.

-- 
With kind regards,

Tom Wijsman (TomWij)
Gentoo Developer

E-mail address  : TomWij@gentoo.org
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