SPARK 2014 User's Guide

SPARK 2014 is a programming language and a set of verification tools designed to meet the needs of high-assurance software development. SPARK 2014 is based on Ada 2012, both subsetting the language to remove features that defy verification, but also extending the system of contracts and aspects to support modular, formal verification. The new aspects support abstraction and refinement and facilitate deep static analysis to be performed including flow analysis and formal verification of an implementation against a specification. SPARK 2014 is a much larger and more flexible language than its predecessor SPARK 2005. The language can be configured to suit a number of application domains and standards, from server-class high-assurance systems (such as air-traffic management applications), to embedded, hard real-time, critical systems (such as avionic systems complying with DO-178C Level A). A major feature of SPARK 2014 is the support for a mixture of proof and other verification methods such as testing, which facilitates in particular the use of unit proof in place of unit testing; an approach now formalized in DO-178C and the DO-333 formal methods supplement. Certain units may be formally proven and other units validated through testing.