Refined Languages (Refined Fortran, Refined C, etc.) are extensions of their parent languages in which it is possible to express parallelism, but impossible to create races. Where strictly deterministic behavior is desired, multiple executions of a Refined Fortran program with the same input data can be guaranteed to either compute the same results or terminate with the same run-time errors regardless of differences in scheduling. Where asynchronous behavior is desired, freedom from races can be guaranteed. The Refined Languages approach achieves its goal by extending sequential imperative programming languages with data- (rather than control-) oriented terms. Specification of Refined ANSI Fortran `77, and construction of an interprocedural Fortran `77 code analysis tool are complete. This award is to modify the specification to Fortran `8X, extend the analysis tool into a Refined Fortran `8X compiler, and exploit the special features of Refined Languages to construct a Refined Fortran `8X symbolic debugger. Formal study of the comparative expressive powers of control-oriented parallel imperative languages and data- oriented parallel imperative languages will ensue.
