Hi Alwyn, To be honest, I believe most folks are using cvs-1.12.13.tar.gz when they build on any recent macOS release. I just checked that it builds on macOS 10.14.6 (with warnings).
You may find it useful to consider using homebrew https://coolestguidesontheplanet.com/installing-homebrew-on-macos-sierra-package-manager-for-unix-apps/ and/or https://getgrav.org/blog/macos-catalina-apache-upgrade-homebrew if you already have it. Then just 'brew install cvs' and you are done. Good luck, -- Mark
