Safety Critical Software in C++

To evaluate the suitability of C++ for safety-critical applications [Bin95] and to formulate guidelines for its use in these, the concept of a safety-critical application must first be defined. A safety-critical application [HIS99, Saf00] is one where failure to stay within the bounds of safe operation leads to unacceptable results. Unacceptable results are those which pose a threat to human life, lead to damage of equipment, to excessive pollution, . . . To formalize acceptability –to allow quantitative assessment and support decision-making– the impact is typically modelled as a weighted dollar cost. If this cost exceeds a threshold (often imposed by law), behaviour is deemed unacceptable. Hecht and Brill [HB97] propose a conceptual framework which starts from generic attributes defining the general safety-related quality of software and which leads to language-specific guidelines. The generic attributes are