.. _Specialized_Needs_Annexes: ************************* Specialized Needs Annexes ************************* Ada 95, Ada 2005, and Ada 2012 define a number of Specialized Needs Annexes, which are not required in all implementations. However, as described in this chapter, GNAT implements all of these annexes: *Systems Programming (Annex C)* The Systems Programming Annex is fully implemented. *Real-Time Systems (Annex D)* The Real-Time Systems Annex is fully implemented. *Distributed Systems (Annex E)* Stub generation is fully implemented in the GNAT compiler. In addition, a complete compatible PCS is available as part of the GLADE system, a separate product. When the two products are used in conjunction, this annex is fully implemented. *Information Systems (Annex F)* The Information Systems annex is fully implemented. *Numerics (Annex G)* The Numerics Annex is fully implemented. *Safety and Security / High-Integrity Systems (Annex H)* The Safety and Security Annex (termed the High-Integrity Systems Annex in Ada 2005) is fully implemented.