Version 8.6 is available upstream. Please consider updating! It seems that version 8.6 is available upstream, while the latest version in the Gentoo tree is 8.5_p20240307-r1. You think this warning is false? Read more about it here.
ACL2 is a logic and programming language in which you can model computer
systems, together with a tool to help you prove properties of those models.
"ACL2" denotes "A Computational Logic for Applicative Common Lisp". ACL2 is
part of the Boyer-Moore family of provers, for which its authors have
received the 2005 ACM Software System Award.