Value Classes Still Need Compiler Sympathy

This post discusses preview features in JDK 28\nJEP 401, a major Valhalla milestone, has been integrated as a preview feature in JDK 28. This is very exciting, as value classes increase both our ability to communicate the semantics of our programs to others and the optimization opportunities available to the JVM.\nHowever, I have seen people online essentially taking a “Value all the classes!” approach to this. I worry that there is a belief that ordinary classes give you a floor on