[gentoo-dev] Re: EAPI-3 draft: slot operator support

[Ryan Hill]

On Thu, 9 Apr 2009 23:36:16 +0530
Nirbheek Chauhan <nirbheek@g.o> wrote:

> On Thu, Apr 9, 2009 at 10:15 PM, Tiziano Müller <dev-zero@g.o> wrote:
> > roughly 90% packages depending on one of:
> >
> > sys-libs/db
>
> Why the hell does this have so many slots in-tree? I am unaware of the
> reasons for it. Horribly changed API every release? How does every
> other distro handle sys-libs/db ?

I know debian has four or five around at any given time.  Others I'm not sure.

> > dev-libs/boost
>
> Has one unmasked slot in-tree

Soon to be four. 

> > dev-lang/python
> >
>
> So, wait, you want to depend on specific slots of python and keep them
> around, and manage all their related bugs? Isn't that exactly the
> opposite of what python upstream suggests, and *ALL* distros do?

Why have python slotted at all then?

> > Besides: We wouldn't need the need_python_rebuild anymore, users could
> > safely uninstall old sys-libs/db versions, old dev-libs/boost versions
>
> @preserved-libs. More generic, a low-level catch-all for library
> breakages, and more convenient for users (rebuild as and when
> possible, not *right now* lest everything break).

We absolutely can _not_ be relying on preserved libs to save us.
It's an umbrella for when the shit hits the fan.  You still get to clean up
afterwards.  It doesn't know anything about interpreted languages (or
anything but libraries for that matter).  And it doesn't do jack for people
uninstalling library slots that are still in use because it doesn't know what
slot a package was built against in the first place, and that's exactly the
case we're talking about here.

> > and the list of packages to reinstall in python-updater boils down to
> > what "paludis -u dev-lang/python:2.4" spits out as reverse-dependencies
> > (or the corresponding portage command).
>
> You mean emerge -C dev-lang/python:2.4 ? That'll say "bai bai python".
>
> In any case, what is wrong with python_need_rebuild ?
>
> Slot operators need changes to the ebuilds, so does python_need_rebuild.
> Slot operators need an EAPI bump for the ebuild, python_need_rebuild doesn't.
>
> So, isn't python_need_rebuild superior.. ?

It's a package-specific workaround for the fact that we have no way of
knowing what packages were built against a particular slot.  We could
implement it for every slotted library in the tree or we could make the
workaround unnecessary.


-- 
gcc-porting,                                      by design, by neglect
treecleaner,                              for a fact or just for effect
wxwidgets @ gentoo     EFFD 380E 047A 4B51 D2BD C64F 8AA8 8346 F9A4 0662