Re: [gentoo-dev] [PATCH 1/6] profiles: add global USE flag 'split-usr'

[William Hubbs]

On Mon, Jul 15, 2019 at 05:29:28AM +0200, Michał Górny wrote:
> On Sun, 2019-07-14 at 19:50 -0400, Mike Gilbert wrote:
> > Signed-off-by: Mike Gilbert <floppym@g.o>
> > ---
> >  profiles/use.desc | 1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/profiles/use.desc b/profiles/use.desc
> > index fc19bbd0bbaa..ec5d4d6bc594 100644
> > --- a/profiles/use.desc
> > +++ b/profiles/use.desc
> > @@ -299,6 +299,7 @@ source - Zip the sources and install them
> >  sox - Add support for Sound eXchange (SoX)
> >  speex - Add support for the speex audio codec (used for speech)
> >  spell - Add dictionary support
> > +split-usr - Splits /bin and /lib from /usr/bin and /usr/lib
> >  sqlite - Add support for sqlite - embedded sql database
> >  ssl - Add support for SSL/TLS connections (Secure Socket Layer / Transport Layer Security)
> >  startup-notification - Enable application startup event feedback mechanism
>
> I have no explicit suggestions right now but this description sounds
> like it's going to magically take care of splitting or merging
> the directories, and AFAIK it doesn't do that.

Mgorny,

you are correct, so the more I think about this, the more I am wondering
about its value as a use flag.

On baselayout you need it, because when the stages are built it sets up
the directories, but after that it does nothing on baselayout. Once we
have 19.0 profiles in the tree and support for older profiles goes away,
you won't need the use flag because this is how all linux builds will be
done.

This should not be taken as a quick way to migrate live systems, we do
not have that yet. I have a script that I am working on for that purpose.

The gen_usr_ldscript function should do nothing on a system which has
the usr merge. Mike told me that you shouldn't check the live filesystem
inside gen_usr_ldscript, so do you know of a better way to check
temporarily than a use flag?

If there is a better way, I would argue that we don't need the use flag
on packages besides baselayout.

William