Verifying a compiler for Java threads

Abstract. A verified compiler is an integral part of every security infra-structure. Previous work has come up with formal semantics for sequen-tial and concurrent variants of Java and has proven the correctness of compilers for the sequential part. This paper presents a rigorous formal-isation (in the proof assistant Isabelle/HOL) of concurrent Java source and byte code together with an executable compiler and its correctness proof. It guarantees that the generated byte code shows exactly the same observable behaviour as the semantics for the multithreaded source code.