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------------------------------------------------------------------------------
-- --
-- GNAT RUN-TIME COMPONENTS --
-- --
-- S Y S T E M . F L O A T _ C O N T R O L --
-- --
-- S p e c --
-- --
-- Copyright (C) 2000-2011, AdaCore --
-- --
-- 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. --
-- --
------------------------------------------------------------------------------
-- Control functions for floating-point unit
package System.Float_Control is
pragma Pure;
-- This is not fully correct, but this unit is with-ed by pure units
-- (eg s-imgrea).
procedure Reset;
pragma Inline (Reset);
-- Reset the floating-point processor to the default state needed to get
-- correct Ada semantics for the target. Some third party tools change
-- the settings for the floating-point processor. Reset can be called
-- to reset the floating-point processor into the mode required by GNAT
-- for correct operation. Use this call after a call to foreign code if
-- you suspect incorrect floating-point operation after the call.
--
-- For example under Windows NT some system DLL calls change the default
-- FPU arithmetic to 64 bit precision mode. However, since in Ada 95 it
-- is required to provide full access to the floating-point types of the
-- architecture, GNAT requires full 80-bit precision mode, and Reset makes
-- sure this mode is established.
--
-- Similarly on the PPC processor, it is important that overflow and
-- underflow exceptions be disabled.
--
-- The call to Reset simply has no effect if the target environment
-- does not give rise to such concerns.
end System.Float_Control;
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