"root-config --glibs" output does not match files in libs/ directory

I explicitly asked this question here …

I guess I would appreciate a “renewed” official statement from @Axel concerning building and using ROOT 6 with “devtoolset-8” and “devtoolset-7” on SL[C]6 / CentOS6 and SL7 / CentOS7 (e.g. maybe some “devtoolset” is known to work on one of them). Even if these system may seem outdated, there are still many batch clusters which use them. The old statement: