Upgrading to systemd-utils and resolving systemd-tmpfiles soft blocking systemd-utils

main menu
News migrating to systemd-utils

Recently a new Gentoo package was added – sys-apps/systemd-utils, which should replace three separate packages sys-apps/systemd-tmpfiles, sys-boot/systemd-boot and sys-fs/udev. As the sys-fs/udev is one of the core packages in the OpenRC world and it can trigger multiple blocking errors and dependency problems.
The sys-apps/systemd-utils has three USE variables for the three replacing packages – udev, boot, and tmpfiles, so the user might add them in make.conf file.
It’s worth noting when upgrading to the sys-apps/systemd-utils, the sys-apps/systemd-tmpfiles and sys-boot/systemd-boot will be removed, but sys-fs/udev is staying in the system with version sys-fs/udev-250 and above. The sys-fs/udev-250 would always pull in sys-apps/systemd-utils[udev] as a dependency. Despite the names including systemd, these packages do not depend on systemd and are meant to be used in OpenRC system.
There is Gentoo news about this upgrade and it can be read with eselect. Check out the article ending for more information.
Here is what a blocking could look like:

root@srv ~ # emerge -vau world
......
......
[ebuild     U  ] dev-lang/php-8.0.27:8.0::gentoo [8.0.25:8.0::gentoo] USE="acl bcmath berkdb bzip2 calendar cli ctype curl enchant exif fileinfo filter flatfile fpm ftp gd gdbm gmp iconv imap intl ipv6 jit mhash mysql mysqli nls opcache pcntl pdo phar posix readline session session-mm sharedmem simplexml soap sockets sqlite ssl tidy tokenizer truetype unicode xml xmlreader xmlwriter xslt zip zlib -apache2 -apparmor -argon2 -cdb -cgi -cjk -coverage -debug -embed -ffi -firebird -inifile -iodbc -kerberos -ldap -ldap-sasl -libedit -lmdb -mssql -oci8-instant-client -odbc -phpdbg -postgres -qdbm (-selinux) -snmp -sodium -spell -systemd -sysvipc -test -threads -tokyocabinet -webp -xpm" 10549 KiB
[ebuild     UD ] sys-apps/man-pages-posix-2013a::gentoo [2017a::gentoo] 909 KiB
[ebuild     U  ] sys-apps/openrc-0.46::gentoo [0.45.2-r1::gentoo] USE="ncurses netifrc pam unicode -audit -bash -debug -newnet (-selinux) -sysv-utils" 242 KiB
[blocks B      ] sys-fs/eudev ("sys-fs/eudev" is soft blocking sys-apps/systemd-utils-251.10-r1)
[blocks B      ] sys-apps/systemd-utils[udev] ("sys-apps/systemd-utils[udev]" is soft blocking sys-fs/eudev-3.2.11-r3)

Total: 113 packages (97 upgrades, 1 downgrade, 15 new), Size of downloads: 554077 KiB
Conflict: 3 blocks (2 unsatisfied)

 * Error: The above package list contains packages which cannot be
 * installed at the same time on the same system.

  (sys-fs/eudev-3.2.11-r3:0/0::gentoo, installed) pulled in by
    sys-fs/eudev required by @selected 

  (sys-apps/systemd-utils-251.10-r1:0/0::gentoo, ebuild scheduled for merge) pulled in by
    sys-apps/systemd-utils[tmpfiles] required by (sys-apps/systemd-tmpfiles-250:0/0::gentoo, ebuild scheduled for merge) USE="" ABI_X86="(64)"
    sys-apps/systemd-utils[tmpfiles] required by (virtual/tmpfiles-0-r3:0/0::gentoo, installed) USE="" ABI_X86="(64)"
    sys-apps/systemd-utils[udev] required by (virtual/udev-217-r5:0/0::gentoo, installed) USE="" ABI_X86="(64)"


For more information about Blocked Packages, please refer to the following
section of the Gentoo Linux x86 Handbook (architecture is irrelevant):

https://wiki.gentoo.org/wiki/Handbook:X86/Working/Portage#Blocked_packages
root@srv ~ # emerge -va sys-apps/systemd-utils


These are the packages that would be merged, in order:

Calculating dependencies... done!
Dependency resolution took 0.84 s.

[ebuild  N     ] acct-group/audio-0-r1::gentoo  0 KiB
[ebuild  N     ] acct-group/cdrom-0-r1::gentoo  0 KiB
[ebuild  N     ] acct-group/dialout-0-r1::gentoo  0 KiB
[ebuild  N     ] acct-group/disk-0-r1::gentoo  0 KiB
[ebuild  N     ] acct-group/kmem-0-r1::gentoo  0 KiB
[ebuild  N     ] acct-group/lp-0-r1::gentoo  0 KiB
[ebuild  N     ] acct-group/sgx-0::gentoo  0 KiB
[ebuild  N     ] acct-group/tape-0-r1::gentoo  0 KiB
[ebuild  N     ] acct-group/tty-0-r1::gentoo  0 KiB
[ebuild  N     ] acct-group/video-0-r1::gentoo  0 KiB
[ebuild  N     ] sys-apps/systemd-utils-251.10-r1::gentoo  USE="acl kmod (split-usr) tmpfiles udev -boot (-selinux) -sysusers -test" ABI_X86="(64) -32 (-x32)" 11194 KiB
[blocks B      ] <sys-apps/systemd-tmpfiles-250 ("<sys-apps/systemd-tmpfiles-250" is soft blocking sys-apps/systemd-utils-251.10-r1)
[blocks B      ] sys-fs/eudev ("sys-fs/eudev" is soft blocking sys-apps/systemd-utils-251.10-r1)
[blocks B      ] sys-apps/systemd-utils[udev] ("sys-apps/systemd-utils[udev]" is soft blocking sys-fs/eudev-3.2.11-r3)

Total: 11 packages (11 new), Size of downloads: 11194 KiB
Conflict: 3 blocks (3 unsatisfied)

 * Error: The above package list contains packages which cannot be
 * installed at the same time on the same system.

  (sys-apps/systemd-tmpfiles-249.9:0/0::gentoo, installed) pulled in by
    sys-apps/systemd-tmpfiles required by @selected 

  (sys-apps/systemd-utils-251.10-r1:0/0::gentoo, ebuild scheduled for merge) pulled in by
    sys-apps/systemd-utils

  (sys-fs/eudev-3.2.11-r3:0/0::gentoo, installed) pulled in by
    sys-fs/eudev required by @selected 


For more information about Blocked Packages, please refer to the following
section of the Gentoo Linux x86 Handbook (architecture is irrelevant):

https://wiki.gentoo.org/wiki/Handbook:X86/Working/Portage#Blocked_packages

A screenshot from the command line, which is colored properly.

main menu
Unresolved Soft blocking tmpfiles and eudev

To solve the soft blocking, first, deselect the old packages, which are soft blocking the sys-apps/systemd-utils. In the above example, the problematic packages are sys-fs/eudev and sys-apps/systemd-tmpfiles. Deselect the packages and try to build only sys-apps/systemd-utils:
Keep on reading!

Review of freshly installed Fedora 37 Xfce Desktop

After the tutorial of how to install Fedora 37 Xfce Desktop this tutorial is mainly to see what to expect from a freshly installed Fedora 36 Xfce Desktop – the look and feel of the new Xfce GUI (Xfce version – 4.16). The Fedora 37 Xfce Desktop is part of Fedora spins – https://spins.fedoraproject.org/xfce/
Here you can find how to Install Fedora 37 Xfce Desktop.
The idea of this article is to see what to expect from Fedora 37 Xfce – the look and feel of the GUI, the default installed programs, and their look and how to do some basic steps with them. Here you’ll find more than 130 screenshots and not so many texts we do not want to turn this review of many texts and version information and 3 meaningless screenshots, which you could not see anything for the user interface because these days it is the primary goal of a Desktop system. You can expect more of this kind of review in the future.
This article is the first part of reviewing the Fedora 36 Xfce Desktop. The second article contains Xfce Settings screenshots are coming soon.

Xfce is a collection of programs that provides a features-rich desktop environment.

Here are some core elements:

  • Window Manager (xfwm4) – Handles the placement of windows on the screen.
  • Panel (xfce4-panel) – Provides a home for window buttons, launchers, app menu and more.
  • Desktop Manager (xfdesktop) – Sets desktop backgrounds, handles icons and more.
  • File Manager (thunar) – Manages your files in a modern, easy-to-use and fast way.
  • Volume Manager (thunar-volman) – Manages removable drives and media for Thunar.
  • Session Manager (xfce-session) – Saves and restores your session, handles startup, autostart and shutdown.
  • Setting System (xfce3-settings) – Configures appearance, display, keyboard, and mouse settings.
  • Application Finder (xfce4-appfinder) – Quickly finds and launches applications installed on your system
  • Settings Daemon (xfconf) – Stores your settings in a D-Bus-based configuration system.
  • A Menu Library (garcon) – Implements a freedesktp.org compliant menu based on GLib and GIO.
  • Thumbnails Services (tumbler) – Implements the thumbnails management D-Bus specification.

Fedora 37 Xfce screenshots

SCREENSHOT 1) Fedora (6.0.7-301.fc37.x86_64) 36 (Xfce)

main menu
grub 2 entry boot

Keep on reading!

Install Fedora 37 Xfce Desktop

This article will show the simple steps of installing a modern Linux DistributionFedora 37 Xfce Desktop with Xfce for the graphical user interface – one of the alternatives, which tries to break the domination of GNOME and partly KDE Plasma. First, it is offered the basic steps for installing the Operating system and then there are some screenshots of the installed system and its look and feel. Here is another article available with more screenshots of the installed and working Fedora 37 Xfce DesktopReview of freshly installed Fedora 37 Xfce Desktop.
Xfce offers a fast, easy and lightweight graphical environment for Linux systems and Fedora teams bring it out-of-the-box with their spins projects – Fedora Xfce Spin
This is the simplest setup. One hard disk device in the system is installed, which is detected as sda and the entire disk will be used for the installation of Fedora 37 Xfce Desktop. All disk information in sda disk device will be permanently deleted by the installation wizard!

The Fedora 36 Xfce Desktop comes with:

  • linux kernel – 6.0.7
  • Xorg X11 server – 1.20.14 and Xorg X11 server XWayland 22.1.5 is used by default
  • Xfce: 4.16, which is the latest stable as of the official Xfce site.

For more packages and versions information the user may check out the Fedora 37 server articles – Software and technical details of Fedora Server 37 including cockpit screenshots.

We used the following ISO for the installation process:
https://download.fedoraproject.org/pub/fedora/linux/releases/37/Spins/x86_64/iso/Fedora-Xfce-Live-x86_64-37-1.7.iso
The ISO may be burnt on a disk or written on a USB stick. Just boot up from it.

SCREENSHOT 1) Boot from the UEFI DVD-ROM device.

It is the same as the USB bootable removable drive. Choose the UEFI USB drive and boot the installation live drive.

main menu
UEFI BIOS DVD-ROM boot

Keep on reading!

Review of freshly installed Fedora 37 KDE Plasma Desktop part 2 – System Settings

This is the part 2 of the Fedora 37 KDE Plasma Desktop review – Review of freshly installed Fedora 37 KDE Plasma Desktop (KDE GUI)
In part 2 only the System Settings of KDE Plasma is presented – the central place to configure and tweak the KDE Plasma – the graphical desktop environment with customizable layouts and panels, virtual desktops and sophisticated widgets. Some of the settings require an administrative account and whenever it is necessary the Plasma platform shows an authentication dialog to escalate privileges.
It worth mentioning the KDE Platform versions in Fedora 37:

  • KDE Plasma version: 5.26.4
  • KDE Frameworks version: 5.100.0
  • QT version: 6.0.12

The System Settings reflects the above versions and the functionality they incorporate.
The main components are:

  • Appearance
  • Workspace
    • Workspace Behavior
    • Windows Management
    • Shortcuts
    • Startup and Shutdown
    • Search
  • Personalization
    • Notifications
    • Users
    • Reginal Settings
    • Accessibility
    • Applications
    • KDE Wallet
    • Online Accounts
    • User Feedback
  • Network
    • Connections
    • Settings
  • Hardware
    • Input Devices
    • Display and Monitor
    • Audio
    • Power Management
    • Bluetooth
    • Color Corrections
    • KDE Connect
    • Printers
    • Removable Storage
    • Thunderbolt
  • System Administration
    • About this System
    • software Update

System Settings may also be started from the console with

myuser@mydesktop ~ $ systemsettings

Here are the System Setting screenshots:

SCREENSHOT 1) Click on System Settings to launch the “System Settings” program.

View and edit KDE and some Linux system settings.

main menu
Main Menu – Favorites

Keep on reading!

Review of freshly installed Fedora 37 KDE Plasma Desktop (KDE GUI)

After the tutorial on how to install Fedora 37 KDE Plasma Desktop this tutorial is mainly to see what to expect from a freshly installed Fedora 37 KDE Plasma Desktop – the look and feel of the new KDE GUI (version 5.26.4 of KDE Plasma). The Fedora 37 KDE Plasma Desktop is part of Fedora spins – https://spins.fedoraproject.org/kde/
Here the user can find how to Install Fedora 37 KDE Plasma Desktop (KDE GUI). Here it worth mentioning the included versions of KDE software for Fedora 36:

  • KDE Plasma version: 5.26.2
  • KDE Frameworks version: 5.99.0, upgradable to 5.100.0
  • QT version: 5.15.6

The idea of this article is just to see what to expect from Fedora 37 KDE Plasma – the look and feel of the GUI, the default installed programs and their look and how to do some basic steps with them, it is included also screenshots of the KDE settings program. Here you’ll find more than 200 screenshots and not so many texts we do not want to turn this review of many texts and version information and 3 meaningless screenshots, which you could not see anything for the user interface because these days it is the primary goal of a Desktop system. You can expect more of this kind of review in the future.
This article is the first part of reviewing the Fedora 36 KDE Plasma. The second article contains KDE System Settings screenshots and it is coming soon.

Some of the interesting screenshots

  • Logging
  • KDE Plasma Overview with Panel Toolbox
  • Fedora KDE main menu
  • Plasma Widgets
  • Activities
  • Install/Update applications with Discover
  • Install applications with dnfdragora
  • review of multiple installed GUI applications and games.
  • Dolphin – the KDE File Manager
  • Kate – Advanced Text Editor
  • KWrite – Text Editor

Fedora 37 KDE Plasma screenshots

SCREENSHOT 1) Fedora (6.0.7-301.fc37.x86_64) 37 (KDE Plasma)

main menu
grub entry boot

Keep on reading!

Install Fedora 37 KDE Plasma Desktop (KDE GUI)

This article will show the simple steps of installing a modern Linux Distribution like Fedora 37 KDE Plasma with KDE for the user graphical interface. First, it is offered the basic steps for installing the Operating system and then there are some screenshots of the installed system and its look and feel of it. Here is another article available with more screenshots of the installed and working Fedora 37 KDE PlasmaReview of freshly installed Fedora 37 KDE Plasma Desktop (KDE GUI). If the user is interested in Gnome as a graphical interface there are two articles on how to install Fedora 37 Workstation Edition, which comes with GNOME and the look and feel of the GNOME – Install Fedora Workstation 37 (Gnome GUI) and Review of freshly installed Fedora 37 Workstation (Gnome GUI)
This is the simplest setup. One hard disk device in the system is installed, which is detected as sda and the entire disk will be used for the installation of Fedora 37 KDE Plasma. All disk information in sda disk device will be permanently deleted by the installation wizard!

The Fedora 37 KDE Plasma Desktop comes with

  • Xorg X server – 22.1.5 XWayland is used by default
  • linux kernel – 6.0.7
  • KDE Plasma version: 5.24.3
  • KDE Frameworks version: 5.99.0
  • QT version: 5.15.6

For more packages and versions information the user may check out the Fedora 37 server articles – Software and technical details of Fedora Server 37 including cockpit screenshots though it is for GNOME installation.

We used the following ISO for the installation process:

https://download.fedoraproject.org/pub/fedora/linux/releases/37/Spins/x86_64/iso/Fedora-KDE-Live-x86_64-37-1.7.iso

It is a LIVE image so you can try it before installing it. The easiest way is just to download the image and burn it to a DVD disk and then follow the installation below:

SCREENSHOT 1) Boot from the UEFI DVD-ROM device.

It is the same as the USB bootable removable drive. Choose the UEFI USB drive and boot the installation live drive.

main menu
UEFI BIOS DVD-ROM boot

Keep on reading!

Software and technical details of Fedora Server 37 including cockpit screenshots

main menu
System Overview

This article is for those of you who do not want to install a whole new operating system only to discover some technical details about the default installation like disk layout, packages included, software versions, and so on. Here we are going to review in several sections what is like to have a default installation of Fedora 37 Server using a real not virtual machine!
The kernel is 6.0.11 it detects successfully the Threadripper 1950X AMD and the system is stable (we booted in UEFI mode).
The installation procedure uses default options for all installation setups – Minimal network installation of Fedora 37 Server

Software

With Fedora Server 37 you can have

  • linux kernel – 6.0.11 (6.0.11-300.fc37.x86_64)
  • System
    • linux-firmware – version: 20221109, release: 20221109-144.fc37.
    • libc – 2.36 (2.36-8.fc37)
    • GNU GCC – 12.2.1 (12.2.1-4.fc37)
    • OpenSSL – 3.0.5 (1:3.0.5-3.fc37) and 1.1.1q (1:1.1.1q-2.fc37)
    • coreutils – 9.1 (9.1-6.fc37)
    • yum – Depricated and replaced with dnf
    • dnf – 4.14.0 (4.14.0-1.fc37)
    • rsyslog – 8.2204.0 (8.2204.0-3.fc37)
    • NetworkManager – 1.40.6 (1:1.40.6-1.fc37)
  • Servers
    • Apache – 2.4.54 (2.4.54-5.fc37)
    • Nginx – 1.22.1 (1:1.22.1-1.fc37)
    • MySQL server – 8.0.31 (8.0.31-1.fc37)
    • MariaDB server – 10.5.18 (3:10.5.18-1.fc37)
    • PostgreSQL – 14.3 (14.3-8.fc37)
  • Programming
    • PHP – 8.1.13 (8.1.13-1.fc37)
    • python – The default is 3.11.0 (3.11.0-1.fc37) and many more available – 3.10.8 (3.10.8-3.fc37), 3.12.0 (3.12.0~a2-1.fc37), 3.9.15 (3.9.15-3.fc37), 3.8.15 (3.8.15-2.fc37), 3.7.15 (3.7.15-2.fc37), 3.6.15 (3.6.15-14.fc37) and also includes the older 2.7.18 (2.7.18-25.fc37)
    • perl – 5.36.0 (4:5.36.0-492.fc37)
    • ruby – 3.1.3 (3.1.3-172.fc37)
    • OpenJDK – the latest 19 – 19.0.1.0.10 (1:19.0.1.0.10-2.rolling.fc37) and also includes 1:17.0.5.0.8 (1:17.0.5.0.8-1.fc37), 11.0.17.0.8 (1:11.0.17.0.8-1.fc37) and 1:1.8.0.352 (1:1.8.0.352.b08-2.fc37)
    • Go – 1.19.3 (1.19.3-2.fc37)
    • Rust – 1.65.0 (1.65.0-1.fc37)
    • llvm – the latest 15.0.4 (15.0.4-1.fc37), 14.0.0 (14.0.0-1.fc36) and the old 7.0.1 (7.0.1-7.fc36.4), 8.0.1 (8.0.1-3.fc37), 9.0.1 (9.0.1-15.fc35), 10.0.0 (10.0.0-13.fc35), 11.1.0 (11.1.0-6.fc35), 12.0.1 (12.0.1-2.fc35) and 13.0.1 (13.0.1-2.fc37)
    • Subversion – 1.14.2 (1.14.2-8.fc37)
    • Git – 2.38.1 (2.38.1-1.fc37)

Note: Not all of the above software comes installed by default. The versions above are valid as of December 2022, these are the minimum versions you get with Fedora Server 37 now, and updating it after the initial date may update some of the above packages with newer versions.

Installed packages are 679 occupying 1.8G space:. Note, this is Fedora Server Install, not minimal install. The server install includes the web console – cockpit version 254.

[root@srv ~]# dnf list installed|wc -l
679
[root@srv ~]# df -h /
Filesystem                      Size  Used Avail Use% Mounted on
/dev/mapper/fedora_fedora-root   15G  1.8G   14G  12% /

Keep on reading!

Minimal network installation of Fedora 37 Server

This tutorial will show you the simple steps of installing a modern Linux Distribution Fedora 37 Server edition. Fedora line offers many bleeding-edge Linux technologies than the more enterprise CentOS of the same RPM Linux family.

In fact, if the user needs a server with the latest Linux stable software Fedora server is the right and easy choice for a server!

Here are some basic data from the default installation setup settings:

  1. Installed packages – ~678 occupying 1.7G of space.
  2. 3 partitions when using automatic partition layout – boot efi, boot and root.
  3. xfs used for the root partition.

The Fedora 37 Server comes and updates to the latest stable Linux:

  • Linux kernel : 6.0.11.
  • Python : 3.11
  • GLibc : 2.36
  • OpenSSL : 3.0.5
  • systemd : 251.8

More detailed software overview here – Software and technical details of Fedora Server 37 including cockpit screenshots.

Of course, one can expect the latest version of GCC (12.2.1), PHP (8.1.13), GO (1.19.3), MySQL Server (8.0.31), PostgreSQL (14.3), Nginx (1.22.1), Apache (2.4.54) and so on. Almost all of them are the latest stable version on their Internet sites.
Just be careful, the Fedora life cycle is 13 months from the release to the EOL (End of Life)! Of course, a dist-upgrade is supported and indeed, it has been flawless for years!

We used the following ISO for the installation process from https://getfedora.org/en/server/download/:

https://download.fedoraproject.org/pub/fedora/linux/releases/37/Server/x86_64/iso/Fedora-Server-netinst-x86_64-37-1.7.iso

It is a LIVE image so you can try it before installing it. The easiest way is to download the image and burn it to a DVD or USB stick disk and then follow the installation below (a USB flash drive could be also created from this ISO). The netinstall installation is as simple as having a good Internet connection to download the packages, the installation wizard automatically detects the closest mirror, from which it will download the packages. Essentially, the network does not differ from the ordinary installation except it expects to download the packages from the Internet.

SCREENSHOT 1) If you booted from the DVD/USB you would get this first screen – select “Install Fedora 37” and hit Enter

main menu
Install Fedora 37 grub entry

Keep on reading!

Review of freshly installed Fedora 37 Workstation (Gnome GUI)

After the tutorial of Install Fedora Workstation 37 (Gnome GUI) this tutorial is mainly to see what to expect from a freshly installed Fedora 36 Workstation – the look and feel of the GUI (Gnome – version 43.0).

  • Xorg X11 server – 1.20.14 and Xorg X11 server XWayland 22.1.5 is used by default
  • GNOME (the GUI) – 43.0
  • linux kernel – 6.0.7

The idea of this tutorial is just to see what to expect from Fedora 37 Workstation (Gnome)the look and feel of the GUI, the default installed programs, and their look and how to do some basic steps with them. Here the reader finds more than 204 screenshots and not so much text the main idea is not to distract the user with much text and version information and 3 meaningless screenshots , which the reader cannot see anything for the user interface, but these days the user interface is the primary goal of a Desktop system. More reviews of this kind will follow in the future …

For all installation and review articles, real workstations are used, not virtual environments!

SCREENSHOT 1) Fedora Linux (6.0.7-301.fc37.x86_64) 37 (Workstation Edition)

main menu
grub 2.06 entry boot

Keep on reading!

Gentoo clang-15: error: does not contain a GCC installation

main menu
emerge firefox

Trying to build a package resulted in a building failure because a Clang could not find GNU GCC installation as the error shows.

Executing just x86_64-pc-linux-gnu-clang-15 the same error.

[root@srv ~]# x86_64-pc-linux-gnu-clang-15 
clang-15: error: '/usr/lib/gcc/x86_64-pc-linux-gnu/12.2.0' does not contain a GCC installation
clang-15: error: no input files

Apparently, because the latest upgrade of GNU GCC went from 12.2.0 to 12.2.1_p20221008 and the directory changed to /usr/lib/gcc/x86_64-pc-linux-gnu/12.
The Clang binaries read several configuration files and one of them was not updated when the GCC had been upgraded. The configuration file /etc/clang/gentoo-gcc-install.cfg has the wrong path, because the gcc-config version was an old one or the configuration file is generated only on GCC major version, not in the minor. But the last upgrade didn’t modified the Clang configuration file /etc/clang/gentoo-gcc-install.cfg

To resolve this issue, the user may edit the file manually or just use gcc-config to revert to the older and then to the new GCC version at once. List the currently installed GCC versions in the system and choose one.

[root@srv ~]# gcc-config -l
 [1] x86_64-pc-linux-gnu-8.2.0
 [2] x86_64-pc-linux-gnu-8.3.0
 [3] x86_64-pc-linux-gnu-9.2.0
 [4] x86_64-pc-linux-gnu-10.3.0
 [5] x86_64-pc-linux-gnu-11.3.0
 [6] x86_64-pc-linux-gnu-12 *
[root@srv ~]# gcc-config x86_64-pc-linux-gnu-11.3.0
 * Switching native-compiler to x86_64-pc-linux-gnu-11.3.0 ...
>>> Regenerating /etc/ld.so.cache...                                                                  [ ok ]
 * If you intend to use the gcc from the new profile in an already
 * running shell, please remember to do:

 *   . /etc/profile

[root@srv ~]#  gcc-config x86_64-pc-linux-gnu-12
 * Switching native-compiler to x86_64-pc-linux-gnu-12 ...
>>> Regenerating /etc/ld.so.cache...                                                                  [ ok ]
 * If you intend to use the gcc from the new profile in an already
 * running shell, please remember to do:

 *   . /etc/profile
[root@srv ~]# . /etc/profile

Check the sys-devel/gcc-config for available upgrades and do them if there are!
More Gentoo tips here.