> This log has "-mtune=option: not valid". I guess something has changed
> here with gcc 9 that the cmake script doesn't like?


I've tailored a patch for CMakeLists.txt to fix the build [1].  If you
agree, I'll push to SCM (including update to v5.1.0) and build it.

Björn


[1]  https://koji.fedoraproject.org/koji/taskinfo?taskID=32767716