Re: [gentoo-user] preparing for profile switch -- major problem

[Alan McKinnon <alan.mckinnon@gmail.com>]

On 07/12/2017 07:44, John Covici wrote:
> Hi. In preparing for the profile switch and the emerge -e world, I
> have run into a serious problem with perl.  I think I saw on this list
> where perl 5.26 was going to have problems -- maybe until it is
> stabilized -- but if I mask it off,  I get the following:

Unmask the latest perl and update world with the old profile

This will go smoothly as the perl team did an excellent job making sure
everything perl-ish in the tree works in concert with everything else.
However I do recall that trying to do it with a partial world update
didn't work - too many affected packages, so trying just perl + deps did
not work. Rather do a normal world update.

Once done, then switch your profile to 17.0 and do the giant emerge -e
world that requires.

tl;dr

the news message about perl might make you think the sky will fall on
your head and all your kittens will die, this is actually not true.

The v5.26 updates mostly had to do with perl's search path for perl
modules. Just like how we've frowned on having "." in the shell PATH for
decades, perl now implemented something like that for modules too. The
possible problem anticipated is that modules would now break if a
modules could not find another module it needs. But this really only
applied to modules outside the perl distribution itself. And the Gentoo
perl team dealt with all that already

It's widely discussed all over the internet in all the usual places, you
are only affected if one of more of these applies:

- you write perl modules yourself (solution: update your own code)
- you use many ancient cpan modules that no-one touched for yonks
(solution: maybe use currently supported modules instead)
- you heavily rely on a third party perl app that might not have been
updated - musicbrainz and radiator come to mind as examples (solution:
harass your app vendor)

-- 
Alan McKinnon
alan.mckinnon@gmail.com