1. © Andrew IrelandGrand Challenges for Computing Research 2004 The Verifying Compiler Andrew Ireland Dependable Systems Group School of Mathematical & Computer Sciences Heriot-Watt University Edinburgh

2. © Andrew IrelandGrand Challenges for Computing Research 2004 Overview First steps for a certified code repository Tony Hoare and Jim Woodcock Software safety Kohei Honda A practical perspective Andrew Ireland

3. © Andrew IrelandGrand Challenges for Computing Research 2004 Certified Code Repository Challenge codes

4. © Andrew IrelandGrand Challenges for Computing Research 2004 Certified Code Repository Challenge codes Evidence Machine readable Documentation … Formal proofs

5. © Andrew IrelandGrand Challenges for Computing Research 2004 Certified Code Repository Challenge codes Evidence Machine readable Documentation … Formal proofs conformance transformation test cases verification conditions VC assertions deduction

6. © Andrew IrelandGrand Challenges for Computing Research 2004 Certified Code Repository Open source foundation Strong software engineering Annotations may initially be reengineered At some point users may take ownership May expand to include commercial companies

7. © Andrew IrelandGrand Challenges for Computing Research 2004 Software Safety Compositional program logics & type systems Program logics are typically language specific Applications typically involve multiple languages Verifying compiler project must embrace a multi-language perspective …

8. © Andrew IrelandGrand Challenges for Computing Research 2004 Software Safety VC CJavaC# Language independent specification Possible foundation: name passing processes

9. © Andrew IrelandGrand Challenges for Computing Research 2004 A Practical Perspective Language issues: Choice of languages or language subsets will have significant impact on progress Support for creating and managing redundant annotations Deduction issues: Integrated approach to deduction that supports the productive use of failure and an evolving verification task Programmer-oriented feedback

10. © Andrew IrelandGrand Challenges for Computing Research 2004 A Practical Perspective Proof planning Proof checking ConjecturesTheory Program patterns

11. © Andrew IrelandGrand Challenges for Computing Research 2004 Getting The Ball Rolling … High integrity applications provide a rich source of potential “Challenge Codes”, but are typically not open source. Are there enough suitable open source applications? Do redundant annotations still represent a significant hurdle to programmers? Getting the “right” balance between language specific tools and tools that address multi-language perspective. An integrated approach to deduction requires planning!