Ada 2005 Abstract Interfaces in GNAT

One of the salient object-orientated issues of Ada 2005 are the Abstract Interfaces.Although the concept is not new (it is based on Java interfaces), being Ada a language for reliable and real-time applications its implementation must be efficient and have a bounded worst-case execution time. This paper summarizes parts of the work done by the GNAT Development Team to have an efficient implementation of this language feature.