francescomecca.eu/output/blog/2015/9/11/about-perl-packages-in-gentoo/index.md

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.. title: About Perl packages in Gentoo
.. slug: about-perl-packages-in-gentoo
.. date: 2015-09-11 12:52:25
.. tags: emerge,Gentoo,perl,perl-core,portage conflict,virtual/perl,PesceWanda
.. category: PesceWanda
.. link: 
.. description: 
.. type: text
-->

In this post I wish to explain a bit about Perl related ebuilds in Gentoo and how to update from perl-core to virtual/perl without conflicts.

First of all the core distribution of Perl is included in [dev-lang/Perl](https://packages.gentoo.org/package/dev-lang/perl) along with [modules](http://perldoc.perl.org/index-modules-A.html).

The [perl-core category](https://sources.gentoo.org/cgi-bin/viewvc.cgi/gentoo-x86/perl-core/) in portage contains ebuilds for perl modules, some of which are included in the core perl distibution. The perl-core ebuilds overrides the perl-core modules such that you can update them without recompiling dev-lang/Perl.

Each perl-core module has a corrensponding virtual/perl-* package. The virtual category is used by portage when emerging to take into account that a module can be either provided by dev-lang/perl package or found in perl-core category.

So, what to do in case of blocks when upgrading your Gentoo machine?

Perl-cleaner is a package provided to get rid of these blocks and to migrate from perl-core to virtual/perl-*.

<pre class="wp-code-highlight prettyprint linenums:1">emerge perl-cleaner
emerge dev-lang/perl
perl-cleaner --all</pre>

if you still have problems when upgrading @world you add a backtrack option

<pre class="wp-code-highlight prettyprint linenums:1">emerge -uDN --backtrack=30 @world</pre>

or you can unmerge all perl-core packages and then finally upgrade world

<pre class="wp-code-highlight prettyprint linenums:1">emerge --unmerge perl-core/*</pre>

This will remove all perl-core packages that virtual/perl-* packages will bring back if needed.

<p style="text-align: right;">
  Francesco Mecca
</p>