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------------------------------------------------------------------------------
-- --
-- GNAT RUN-TIME COMPONENTS --
-- --
-- S Y S T E M --
-- --
-- S p e c --
-- (Compiler Version) --
-- --
-- Copyright (C) 1992-2024, Free Software Foundation, Inc. --
-- --
-- This specification is derived from the Ada Reference Manual for use with --
-- GNAT. The copyright notice above, and the license provisions that follow --
-- apply solely to the contents of the part following the private keyword. --
-- --
-- GNAT is free software; you can redistribute it and/or modify it under --
-- terms of the GNU General Public License as published by the Free Soft- --
-- ware Foundation; either version 3, or (at your option) any later ver- --
-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE. --
-- --
-- As a special exception under Section 7 of GPL version 3, you are granted --
-- additional permissions described in the GCC Runtime Library Exception, --
-- version 3.1, as published by the Free Software Foundation. --
-- --
-- You should have received a copy of the GNU General Public License and --
-- a copy of the GCC Runtime Library Exception along with this program; --
-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
-- <http://www.gnu.org/licenses/>. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
-- This version of System is a generic version that is used in building the
-- compiler. Right now, we have a host/target problem if we try to use the
-- "proper" System, and since the compiler itself does not care about most
-- System parameters, this generic version works fine.
pragma Restrictions (No_Implicit_Dynamic_Code);
-- We want to avoid trampolines in the compiler, so it can be used in systems
-- which prevent execution of code on the stack, e.g. in windows environments
-- with DEP (Data Execution Protection) enabled.
pragma Restrictions (No_Finalization);
-- Use restriction No_Finalization to avoid pulling finalization (not allowed
-- in GNAT) inside sem_spark.adb, when defining type Perm_Tree_Access as an
-- access type on incomplete type Perm_Tree_Wrapper (which is required for
-- defining a recursive type).
pragma Restrictions (No_Tasking);
-- Make it explicit that tasking is not used in the compiler, which also
-- allows generating simpler and more efficient code.
package System is
pragma Pure;
-- Note that we take advantage of the implementation permission to make
-- this unit Pure instead of Preelaborable; see RM 13.7.1(15). In Ada
-- 2005, this is Pure in any case (AI-362).
pragma No_Elaboration_Code_All;
-- Allow the use of that restriction in units that WITH this unit
type Name is (SYSTEM_NAME_GNAT);
System_Name : constant Name := SYSTEM_NAME_GNAT;
-- System-Dependent Named Numbers
Min_Int : constant := Long_Long_Integer'First;
Max_Int : constant := Long_Long_Integer'Last;
Max_Binary_Modulus : constant := 2 ** Long_Long_Integer'Size;
Max_Nonbinary_Modulus : constant := 2 ** Integer'Size - 1;
Max_Base_Digits : constant := Long_Long_Float'Digits;
Max_Digits : constant := Long_Long_Float'Digits;
Max_Mantissa : constant := 63;
Fine_Delta : constant := 2.0 ** (-Max_Mantissa);
Tick : constant := 0.01;
-- Storage-related Declarations
type Address is private;
-- Note that we do NOT add pragma Preelaborable_Initialization in this
-- version of System, since it is used for the compiler only, and typical
-- earlier bootstrap compilers don't support this pragma. We don't need
-- it in this context, so there is no problem in omitting it.
Null_Address : constant Address;
Storage_Unit : constant := Standard'Storage_Unit;
Word_Size : constant := Standard'Word_Size;
Memory_Size : constant := 2 ** Standard'Address_Size;
-- Address comparison
function "<" (Left, Right : Address) return Boolean;
function "<=" (Left, Right : Address) return Boolean;
function ">" (Left, Right : Address) return Boolean;
function ">=" (Left, Right : Address) return Boolean;
function "=" (Left, Right : Address) return Boolean;
pragma Import (Intrinsic, "<");
pragma Import (Intrinsic, "<=");
pragma Import (Intrinsic, ">");
pragma Import (Intrinsic, ">=");
pragma Import (Intrinsic, "=");
-- Other System-Dependent Declarations
type Bit_Order is (High_Order_First, Low_Order_First);
Default_Bit_Order : constant Bit_Order :=
Bit_Order'Val (Standard'Default_Bit_Order);
pragma Warnings (Off, Default_Bit_Order); -- kill constant condition warning
-- Priority-related Declarations (RM D.1)
Max_Priority : constant Positive := 30;
Max_Interrupt_Priority : constant Positive := 31;
subtype Any_Priority is Integer range 0 .. 31;
subtype Priority is Any_Priority range 0 .. 30;
subtype Interrupt_Priority is Any_Priority range 31 .. 31;
Default_Priority : constant Priority := 15;
private
type Address is mod Memory_Size;
Null_Address : constant Address := 0;
--------------------------------------
-- 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.
-- This version of system.ads is used only for building the compiler.
-- We really ought to use the proper target system (i.e. the one that
-- corresponds to the host for the compiler), but that causes as yet
-- unsolved makefile problems. For the most part the setting of these
-- parameters is not too critical for the compiler version (e.g. we
-- do not use floating-point anyway in the compiler).
Backend_Divide_Checks : constant Boolean := False;
Backend_Overflow_Checks : constant Boolean := False;
Command_Line_Args : constant Boolean := True;
Configurable_Run_Time : constant Boolean := False;
Denorm : constant Boolean := True;
Duration_32_Bits : constant Boolean := False;
Exit_Status_Supported : constant Boolean := True;
Machine_Overflows : constant Boolean := False;
Machine_Rounds : constant Boolean := True;
Preallocated_Stacks : constant Boolean := False;
Signed_Zeros : constant Boolean := True;
Stack_Check_Default : constant Boolean := False;
Stack_Check_Probes : constant Boolean := False;
Stack_Check_Limits : constant Boolean := False;
Support_Aggregates : constant Boolean := True;
Support_Composite_Assign : constant Boolean := True;
Support_Composite_Compare : constant Boolean := True;
Support_Long_Shifts : constant Boolean := True;
Always_Compatible_Rep : constant Boolean := True;
Suppress_Standard_Library : constant Boolean := False;
Use_Ada_Main_Program_Name : constant Boolean := False;
Frontend_Exceptions : constant Boolean := False;
ZCX_By_Default : constant Boolean := True;
end System;
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