Use modern compilers in CentOS

Often we need a more modern compiler than is included in Red Hat / CentOS for HPC systems. Once an admin sets up GCC Toolset they can be loaded by any user thereafter. Prior to CentOS / RHEL 8, this was known as Developer Toolset devtoolset. CentOS / RHEL 8 introduced GCC Toolsets.

For example, to install and use GFortran 10, have the system admin do:

yum install gcc-toolset-10-gcc-gfortran

Thereafter, users without sudo use the new Gfortran version by:

scl enable gcc-toolset-10 bash

which is for that Terminal session only.