Re: GNAT - System.ads - System Implementation Parameters

[Georg Bauhaus <see.reply.to@maps.futureapps.de>]

anon wrote:

> Gnat uses the "System Implementation Parameters" as a Initialization
> file

> There is no documentation on these Boolean flags because they are use 
> by Adacore (GNAT creators) in house. Also some are slowly be removed 
> while others are becoming non-operational.

As noted in package System, readers should consult the package Targparm.
Indeed, it has quite a lot of documentation talking about these
flags, AFAICS. The package Targparm is part of the publicly available
compiler sources. (I'm not familiar with the innards of GNAT; however,
is usually suffices to read the documentation comments near any
declaration in GNAT sources in order to learn where to find more.
One case is when declarations are grouped under a common description,
such as this one:

   --------------------------------------
   -- System Implementation Parameters --
   --------------------------------------

   --  These parameters provide information about the target that is used
   --  by the compiler. They are in the private part of System, where they
   --  can be accessed using the special circuitry in the Targparm unit
   --  whose source should be consulted for more detailed descriptions
   --  of the individual switch values.

   Backend_Divide_Checks     : constant Boolean := False;
   Backend_Overflow_Checks   : constant Boolean := False;
   Command_Line_Args         : constant Boolean := True;
   Configurable_Run_Time     : constant Boolean := False;
...)