Patch and resume compilation of a failed package in Gentoo – ebuild, local repository or ctrl+Z

A dependency package failed to compile throwing error and existing the emerge of a queue with a hundred and more packages. Or worse you installed a new version of a package and multiple rebuilds are pulled, but one of the dependencies fails and you may end up with a broken system? What can you do? There is no new version of the failed package and yes, there is a bug in the Gentoo’s Bugzilla – https://bugs.gentoo.org/. And there is a solution with a patch, which has not made its way to the production and in Gentoo portage yet.
The package in the portage is broken, no new fixed package is released, but there is a patch to fix your issue. Here is what you can do:

  • Make your own package with the fixed version of the original package and put it in your local repository (not the official one, because on every emerge –sync it will be deleted). You should make a local repository and put the ebuild and all necessary files.
  • Or just download the patch and patch the source in the directory, which still holds the source of the failed package and resume the compilation manually. Then install it. Using this tutorial – Resume installation after a package build error, when emerging firefox under Gentoo
  • Just after the uncompress operation of the emerge press CTRL+Z to put the operation in the background and download and patch. Then bring back the emerge from the background with “fg” command.

The second and third options are not permanent solutions, but they are fast enough to be used in some situations.
Here are steps for the first and second option you may have:

OPTION 1) Make your own package.

Create a local repository (for details Simple steps to create Gentoo custom repository and add a package):

root@srv ~ # mkdir -p /var/db/repos/my-local-portage/{metadata,profiles}
root@srv ~ # cat  << 'EOF' > /var/db/repos/my-local-portage/metadata/layout.conf
masters = gentoo
auto-sync = false
EOF
root@srv ~ # cat  << 'EOF' > /etc/portage/repos.conf/my-local-portage.conf
[my-local-portage]
location = /var/db/repos/my-local-portage 
EOF
root@srv ~ # cat  << 'EOF' > /var/db/repos/my-local-portage/profiles/repo_name
my-local-portage
EOF

Copy the ebuild file of the package you want to modify in the custom repository directory created above (it’s a good idea to copy all the sub-directories, too):
Keep on reading!

Simple steps to create Gentoo custom repository and add a package

Creating a custom repository would give you a chance to fast edit (ebuild) files of existing packages and drop better versions to the custom repository, which then will be used to install in the system. Here is the simplest way to create a Gentoo custom repository without installing any mandatory software. You may check the two Gentoo articles on the subject – https://wiki.gentoo.org/wiki/Custom_repository, which uses repoman (and additional software to install) and https://wiki.gentoo.org/wiki/Handbook:AMD64/Portage/CustomTree#Defining_a_custom_repository, which is part of a bigger article and without a clear example with a package as we are going to show.
Our custom repository name is “my-local-portage”.

STEP 1) Create the directories and basic configuration files for the new custom repository

Just two mandatory directories.

mkdir -p /var/db/repos/my-local-portage/{metadata,profiles}

The minimal configuration in two files:

cat  << 'EOF' > /var/db/repos/my-local-portage/metadata/layout.conf
masters = gentoo
auto-sync = false
EOF
cat  << 'EOF' > /var/db/repos/my-local-portage/profiles/repo_name
my-local-portage
EOF

Fix the permissions

chown -R portage:portage /var/db/repos/my-local-portage

The custom repository is set up. Now only the emerge should get the configuration to check for it in the next step.

STEP 2) Portage global configuration.

Add a file pointing for your custom repository in the Portage global configuration directory “/etc/portage”:

cat  << 'EOF' > /etc/portage/repos.conf/my-local-portage.conf
[my-local-portage]
location = /var/db/repos/my-local-portage
EOF

STEP 3) Add a package in the new custom repository.

The package version may be the same version as in the official Gentoo repository, but the package form the custom repository will be used if no repository is included in the “emerge” command.
For simplicity, we are going not to modify the ebuild file of a copied official package, but the idea is to copy an existing ebuild file and then change it for the user’s needs and the steps are the same as follow.
Just copy the file (and edit it). The package “app-text/calibre” was randomly selected for the example.

mkdir /var/db/repos/my-local-portage/app-text/calibre
cp /usr/portage/app-text/calibre/calibre-4.9.1-r1.ebuild /var/db/repos/my-local-portage/app-text/calibre/

Create the manifest files and you are ready:

cd /var/db/repos/my-local-portage/app-text/calibre/
ebuild calibre-4.9.1-r1.ebuild manifest
>>> Downloading 'ftp://ftp.free.fr/mirrors/ftp.gentoo.org/distfiles/2e/calibre-4.9.1.tar.xz'
--2020-02-06 18:04:59--  ftp://ftp.free.fr/mirrors/ftp.gentoo.org/distfiles/2e/calibre-4.9.1.tar.xz
           => '/usr/portage/distfiles/calibre-4.9.1.tar.xz.__download__'
Resolving ftp.free.fr... 212.27.60.27, 2a01:e0c:1:1598::1
Connecting to ftp.free.fr|212.27.60.27|:21... connected.
Logging in as anonymous ... Logged in!
==> SYST ... done.    ==> PWD ... done.
==> TYPE I ... done.  ==> CWD (1) /mirrors/ftp.gentoo.org/distfiles/2e ... done.
==> SIZE calibre-4.9.1.tar.xz ... 37529656
==> PASV ... done.    ==> RETR calibre-4.9.1.tar.xz ... done.
Length: 37529656 (36M) (unauthoritative)

calibre-4.9.1.tar.xz                       100%[========================================================================================>]  35.79M  5.53MB/s    in 8.0s    

2020-02-06 18:05:08 (4.48 MB/s) - '/usr/portage/distfiles/calibre-4.9.1.tar.xz.__download__' saved [37529656]

>>> Creating Manifest for /var/db/repos/my-local-portage/app-text/calibre

Fix the permissions with

chown -R portage:portage /var/db/repos/my-local-portage

The manifest file contains the hash of the ebuild file and all the additional files if any (for this package there are no additional files). All file needed for the operation will be downloaded so they must be network accessed in the time of executing the command (except in the cases when they have already existed in the distfiles directory and/or the subdirectories of the /var/db/repos/my-local-portage/app-text/calibre)
Keep on reading!