This appendix is not part of the standard definition of the Ada programming language.
The Ada language definition allows for certain machine-dependences in a controlled manner. No machine-dependent syntax or semantic extensions or restrictions are allowed. The only allowed implementation-dependences correspond to implementation-dependent pragmas and attributes, certain machine-dependent conventions as mentioned in chapter 13, and certain allowed restrictions on representation clauses.
The reference manual of each Ada implementation must include an appendix (called Appendix F) that describes all implementation-dependent characteristics. The appendix F for a given implementation must list in particular:
Style Guide references: 4.1.1 Separate Compilation Capabilities, 5.4.1 Heterogeneous Data, 7.1.1 Global Assumptions, 7.1.2 Actual Limits, 7.1.3 Comments, 7.1.5 Encapsulating Implementation Dependencies, 7.1.6 Implementation-Added Features, 7.2.1 Predefined Numeric Types, 7.2.4 Accuracy Constraints, 7.4.3 Package Calendar, Type Duration, and System.Tick, 7.6.2 Package System, 7.6.3 Machine Code Inserts, 7.6.5 Implementation-Defined Pragmas and Attributes, 7.6.8 Run Time Dependencies
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