Splint is a tool for statically checking C programs for security vulnerabilities and coding mistakes. With minimal effort, Splint can be used as a better lint.
GNU DDD is a graphical front-end for command-line debuggers such as GDB, DBX, WDB, Ladebug, JDB, XDB, the Perl debugger, the bash debugger, or the Python debugger. Besides ``usual'' front-end features such as viewing source texts, DDD has become famous through its interactive graphical data display, where data structures are displayed as graphs.
The OBJ languages are broad spectrum algebraic programming and specification languages, based on order sorted equational logic, possibly enriched with other logics (such as rewriting logic, hidden equational logic, or first order logic), and providing the powerful module system of parameterized programming...All the OBJ languages are rigorously based upon a logical system; more precisely, they are logical languages, in the sense that their programs are sets of sentences in some logical system, and their operational semantics is given by deduction in that logical system.