Re: [gentoo-dev] pkg_pretend USE validation and VALID_USE alternative

[Ciaran McCreesh]

On Thu, 1 Apr 2010 04:38:36 -0700
Brian Harring <ferringb@×××××.com> wrote:
> > But if the kernel sources symlink is changed by installing new
> > kernel sources, there won't be a valid .config in the new directory
> > anyway.
>
> Oddly enough, I actually have an ebuild that directly contradicts
> that- used for managing my sources w/in kvms.

Your own personal ebuilds are an exception that don't apply to
everyone else. For ebuilds using kernel-2.eclass with USE=symlink, a
missing .config is exactly what happens.

> > Thus, pkg_pretend doesn't introduce any new breakage.
>
> Regardless of my own usage, ironically you just inadvertantly pointed
> out a whole class of false negatives pkg_pretend has.
>
> Specifically,
>
> 1) starting w/ a configured kernel at /usr/src/linux
> 2) merging a version of aufs2 requiring new kernel sources
> 3) emerge runs pkg_pretend.  aufs2 does it's checks w/in pkg_pretend,
> sees the old configured kernel and thinks things are fine
> 4) new kernel sources get merged.  /usr/src/linux is no lnger a
> configured kernel.
> 5) aufs2 blows up during its build due to an unconfigured
> kernel.
>
> Since I'm in the mood for a Scooby Doo quote, "wraut-wroh".

This isn't a breakage that's introduced by pkg_pretend. It's a breakage
that's already there.

-- 
Ciaran McCreesh