See the following documents for further information on GNAT:
GNAT User’s Guide for Native Platforms,
which provides information on how to use the
GNAT development environment.
Ada 95 Reference Manual, the Ada 95 programming language standard.
Ada 95 Annotated Reference Manual, which is an annotated version
of the Ada 95 standard. The annotations describe
detailed aspects of the design decision, and in particular contain useful
sections on Ada 83 compatibility.
Ada 2005 Reference Manual, the Ada 2005 programming language standard.
Ada 2005 Annotated Reference Manual, which is an annotated version
of the Ada 2005 standard. The annotations describe
detailed aspects of the design decision.
Ada 2012 Reference Manual, the Ada 2012 programming language standard.
DEC Ada, Technical Overview and Comparison on DIGITAL Platforms,
which contains specific information on compatibility between GNAT and
DEC Ada 83 systems.
DEC Ada, Language Reference Manual, part number AA-PYZAB-TK, which
describes in detail the pragmas and attributes provided by the DEC Ada 83
compiler system.