How to think about updating from devel and building books - acl2/acl2 GitHub Wiki

Sol wrote something pretty elegant, and I thought it was worth copying into the public domain. In reality, it should probably be a doc topic that's linked from one or more of the "getting started with git" topics.

I think it's pretty common for our build system to fail in weird ways due to ACL2 changes. In principle, we should have every cert/pcert/etc depend on the ACL2 executable, because if ACL2 is changed there's no way to be sure they won't need updating. But in practice, I think it's often unnecessary to rebuild all the books after an ACL2 change.

We should have dependencies in place to prevent any change other than to ACL2 itself from causing such a problem, I think.