On el8/el9/newer, how do you get newer versions of software like python3, gcc, java, etc?

Question

For example on el7:

• to develop an nvidia CUDA application you need a newer gcc than the default gcc version 4.8.x and to get the newer version you would use a software repo called "Software Collections" (SCL)
• the base python3 is 3.6 and you need newer python modules and so you install python3.8 from SCL

Starting on el8, and el9: the SCL is deprecated and so there is a different method for installing and configuring newer versions of gcc and python3.

On el8/el9/newer, how do you get newer versions of software like python3, gcc, java, etc?

Answer 1

in a nutshell, here are some examples for how to install and configure

• for python3 to get python3.9: dnf install -y python39 && alternatives --set python3 $(command -v python3.9)
• for gcc to get gcc-12: dnf install gcc-toolset-12 && source scl_source enable gcc-toolset-12
• for java to get java-17: dnf install java-17 && bin_java_filename=$(rpm -qa|grep java-17|xargs rpm -ql|grep "bin\/java$"|head -1) && alternatives --set java ${bin_java_filename}
• tested on rocky8, rocky9

---

which repo has the newer software versions?

• the old method using "SCL" was deprecated
• the new method is to use a repo called "appstream"
• here is a post written by the distro maintainers explaining the change https://developers.redhat.com/blog/2018/11/15/rhel8-introducing-appstreams
• the repo is enabled by default

how to: install newer software versions?

• for python3: dnf install python39
• for gcc: dnf install gcc-toolset-12

how to: change the system default?

• for python3: alternatives --set python3 $(command -v python3.9)
• for gcc:
  • edit your user .bashrc or .bash_profile or create a new file under /etc/profile.d/ with the following: source scl_source enable gcc-toolset-12
  • i thought scl_source would go away in el8, el9 but apparently not
  • for more info on scl_source go to this link https://unix.stackexchange.com/a/195219/5510 or Permanently enable RHEL scl

p.s. what is the difference between alternatives and update-alternatives?

• the original tool is called update-alternatives and is from Debian linux distro
• in EnterpriseLinux, Redhat rewrote the tool and called it alternatives and when you install alternatives the package also installs a symlink with name update-alternatives on your env var PATH to help you find the tool
• the two are similar but not the same because their source code is different