5.6 Predeclared Runtime Services
Language-specific annexes to this standard will define predeclared subprograms that are included with every thread, and process implementation.  Names used for explicitly declared components, features, connections and behaviors must be distinct from the names of all standard predeclared components.
Every language-specific annex will define a source language application program interface for the predeclared subprograms, shown below.
The following subprograms can be called by any application thread from its source text:
    Raise_Event : subprogram ;
    Raise_Error : subprogram ;
The following are subprograms, whose calls are only necessary in application source text, if the particular implementation method does not perform those functions as part of its AADL runtime support.
    Await_Dispatch : subprogram ;
    Get_Resource : subprogram ;
    Release_Resource : subprogram ;