What specs on pc/build machine here ? sounds excessively slow.Doing a make clean for me means waiting 8 to 10 hours for a build. That's something I want to avoid when I'm trying out fixes, new code, etc. At minimum, even the simplest change takes 15 minutes to compile.
using ccache ? Currently getting cache hit rate 94.96 %
Grab an SSD and start building on that.
Clean build here in under an 1hr, a dirty build 3mins