Version 2.4.0 is available upstream. Please consider updating! It seems that version 2.4.0 is available upstream, while the latest version in the Gentoo tree is 2.3.4-r1. You think this warning is false? Read more about it here.
STP is a constraint solver (or SMT solver) aimed at solving
constraints of bitvectors and arrays. These types of
constraints can be generated by program analysis tools, theorem
provers, automated bug finders, cryptographic attack tools,
intelligent fuzzers, model checkers, and by many other
applications.