upgrade code base for the modern toolchain

Instead of migrating to CentOS 8 (see update below), try using Spack as Euler admins do and stay compatible with Euler's GCC 8.2.0 toolchain:

• gcc 8.2.0
• cmake/3.4.3 - 3.16.5
• boost/1.62.0 - 1.73.0
• vtk/8.1.2 (only w/ mpi support on Euler, i.e. in OpenMPI 4.0.2 > GCC 8.2.0 modules)

For comparison, CentOS 8 defaults at 2020.12.10 (cf. https://pkgs.org/; see update below):

• cmake-3.11.4
• gcc-8.3.1
• boost-1.66.0
• ?vtk-9.0 (external; not even in 3rd party repos)

[Update 2022.01.25] Alternative free CentOS-like images: https://pythonspeed.com/articles/centos-8-is-dead/ => e.g. use RedHat’s Universal Base Image (redhat/ubi8) w/ Spack.

Note: for python-based Spack, consider using Python-variant of the image (registry.access.redhat.com/ubi8/python-39), or, alt., little more performant Debian/Ubuntu-based one - cf. https://pythonspeed.com/articles/base-image-python-docker-images/ .

[Update 2020.12.10]

CentOS is becoming a rolling Linux distribution [...]

A rolling-release Linux is one that's constantly being updated. [...]

Red Hat will continue to support CentOS 7 and produce it through the remainder of the RHEL 7 life cycle. That means if you're using CentOS 7, you'll see support through June 30, 2024.

As for CentOS 8, that's another story. Red Hat will only continue to update it until the end of 2021. CentOS 8 users had expected support until 2029.

https://www.zdnet.com/article/red-hat-resets-centos-linux-and-users-are-angry/

The goal to upgrade to modern toolchain remains, but how? Will CentOS 7 become updates to C/C++ toolchain or should we switch to Debian/Ubuntu?