Debugging concurrent Ada programs by deterministic execution

A language-based approach to deterministic execution debugging of concurrent Ada programs is presented. The approach is to define synchronization (SYN)-sequences of a concurrent Ada program in terms of Ada language constructs and to replay such SYN-sequences without the need for system-dependent debugging tools. It is shown how to define a SYN-sequence of a concurrent Ada program in order to provide sufficient information for deterministic execution. It is also shown how to transform a concurrent Ada program P so that the SYN-sequences of previous executions of P can be replayed. This transformation adds an Ada task to P that controls program execution by synchronizing with the original tasks in P. A brief description is given of the implementation of tools supporting deterministic execution debugging of concurrent Ada programs.>