Long gone are the days when program veri? cation was a task carried out merely by hand
with paper and pen. For one, we are increasingly interested in proving actual program …

Fault tolerance mechanisms are a key ingredient of dependable systems. In particular,
software-implemented hardware fault tolerance (SIHFT) is gaining in popularity, because of …

Loops are a major bottleneck in formal software verification, because they generally require
user interaction: typically, induction hypotheses or invariants must be found or modified by …

We present a theorem proving approach to analysis of secure information flow using the
technique of inspecting failed proofs and open goals. We then introduce an approximate …

This thesis is concerned with analysis of programs. Analysis of programs can be divided into
two camps: static analysis and formal verification. Static program analyses compute a result …

This thesis presents logical and algebraic approaches for analyzing imperative recursive
algorithms and for synthesizing optimal algorithms. First we develop, formalize, and prove …

We present a logic-based verification method for imperative loops (including ones with
abrupt termination) and the automatic proof of its soundness. The verification method …

Induction is a powerful method that can be used to prove the total correctness of program
loops. Unfortunately the induction proving process in an interactive theorem prover is often …

Loops and other unbound control structures constitute a major bottleneck in formal software
verification, because correctness proofs over such control structures generally require user …

This thesis is about formal specification and formal verification of software and consists of
three different parts. In the first two parts, the formal specification language OCL is treated in …