Semantics and Verification of Software


  • 2018-12-18: we are online!

Schedule (TBA)

Type Day Time Room Start Lecturer
Lecture Mon 14:30 – 16:00 AH 6 15 Apr Noll
Lecture Thu 10:30 – 12:00 5056 4 Apr Noll
Exercise Fri 10:30 – 12:00 5056 26 Apr Matheja


The analysis and verification of software systems is an important issue. In particular, safety-critical systems are ones in which errors can be disastrous: loss of life, major financial losses, etc. Techniques to safeguard against such scenarios are essential for such systems. Testing can identify problems, especially if done in a rigorous fashion, but is generally not sufficient to guarantee a satisfactory level of quality. Formal methods, on the other hand, offer techniques ranging from the description of requirements in a formal notation to allow for rigorous reasoning about them, to techniques for automatic verification of software.
The goal of this course is to provide an introduction to the field of formal semantics for programming languages, with particular emphasis on software verification. The following topics will be covered:
  1. The imperative model language WHILE
  2. Operational semantics of WHILE
  3. Denotational semantics of WHILE
  4. Equivalence of operational and denotational semantics
  5. Axiomatic semantics of WHILE
  6. Compiler correctness
  7. Extensions: procedures, parallelism, …


Basic knowledge of the following relevant undergraduate courses is expected:
  • Programming (essential concepts of imperative and object-oriented programming languages and elementary programming techniques)
  • Formal Languages and Automata Theory (regular and context-free languages, finite and pushdown automata)
  • Mathematical Logic

Slides & Exercises

No. Date Topic Slides Handout Exercises Solutions
1 4 Apr Introduction l01 l01    
2 12 Apr, 5056 Operational Semantics of WHILE I (Evaluation of Expressions) l02 l02    
3 15 Apr Operational Semantics of WHILE II (Execution of Statements) l03 l03    
4 18 Apr Operational Semantics of WHILE III (Summary & Application to Compiler Correctness) l04 l04 ex-01  
5 25 Apr          
6 2 May          
7 6 May          
8 9 May          
9 20 May          
10 23 May          
11 27 May          
12 3 Jun          
13 6 Jun          
14 17 Jun          
15 24 Jun          
16 27 Jun          
17 1 Jul          
18 4 Jul          
19 8 Jul          
20 11 Jul          


  • The kind of exam (written or oral) will be announced later.
  • Registration will be possible via RWTHonline.
  • Admission requires to achieve 50% of the points in the exercises.

Evaluation results

  • Lecture (TBA)
  • Exercises (TBA)

Further information

  • The lectures will be given in German or English, depending on the language proficiency of the audience.
  • The slides and other course material will be in English. There are no lecture notes (yet); the course material will consist of slides.

Background Literature