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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- A D A . E X C E P T I O N S . E X C E P T I O N _ P R O P A G A T I O N --
-- --
-- B o d y --
-- --
-- Copyright (C) 1992-2006 Free Software Foundation, Inc. --
-- --
-- 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 2, 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. See the GNU General Public License --
-- for more details. You should have received a copy of the GNU General --
-- Public License distributed with GNAT; see file COPYING. If not, write --
-- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
-- Boston, MA 02110-1301, USA. --
-- --
-- As a special exception, if other files instantiate generics from this --
-- unit, or you link this unit with other files to produce an executable, --
-- this unit does not by itself cause the resulting executable to be --
-- covered by the GNU General Public License. This exception does not --
-- however invalidate any other reasons why the executable file might be --
-- covered by the GNU Public License. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
-- This is the default version, using the __builtin_setjmp/longjmp EH
-- mechanism.
with System.Storage_Elements; use System.Storage_Elements;
pragma Warnings (Off);
-- Since several constructs give warnings in 3.14a1, including unreferenced
-- variables and pragma Unreferenced itself.
separate (Ada.Exceptions)
package body Exception_Propagation is
procedure builtin_longjmp (buffer : Address; Flag : Integer);
pragma No_Return (builtin_longjmp);
pragma Import (C, builtin_longjmp, "_gnat_builtin_longjmp");
---------------------
-- Setup_Exception --
---------------------
procedure Setup_Exception
(Excep : EOA;
Current : EOA;
Reraised : Boolean := False)
is
pragma Unreferenced (Excep, Current, Reraised);
begin
-- In the GNAT-SJLJ case this "stack" only exists implicitly, by way of
-- local occurrence declarations together with save/restore operations
-- generated by the front-end, and this routine has nothing to do.
null;
end Setup_Exception;
-------------------------
-- Propagate_Exception --
-------------------------
procedure Propagate_Exception
(E : Exception_Id;
From_Signal_Handler : Boolean)
is
pragma Inspection_Point (E);
Jumpbuf_Ptr : constant Address := Get_Jmpbuf_Address.all;
Excep : constant EOA := Get_Current_Excep.all;
begin
-- Compute the backtrace for this occurrence if corresponding binder
-- option has been set. Call_Chain takes care of the reraise case.
Call_Chain (Excep);
-- Note on above call to Call_Chain:
-- We used to only do this if From_Signal_Handler was not set,
-- based on the assumption that backtracing from a signal handler
-- would not work due to stack layout oddities. However, since
-- 1. The flag is never set in tasking programs (Notify_Exception
-- performs regular raise statements), and
-- 2. No problem has shown up in tasking programs around here so
-- far, this turned out to be too strong an assumption.
-- As, in addition, the test was
-- 1. preventing the production of backtraces in non-tasking
-- programs, and
-- 2. introducing a behavior inconsistency between
-- the tasking and non-tasking cases,
-- we have simply removed it
-- If the jump buffer pointer is non-null, transfer control using
-- it. Otherwise announce an unhandled exception (note that this
-- means that we have no finalizations to do other than at the outer
-- level). Perform the necessary notification tasks in both cases.
if Jumpbuf_Ptr /= Null_Address then
if not Excep.Exception_Raised then
Excep.Exception_Raised := True;
Exception_Traces.Notify_Handled_Exception;
end if;
builtin_longjmp (Jumpbuf_Ptr, 1);
else
Exception_Traces.Notify_Unhandled_Exception;
Exception_Traces.Unhandled_Exception_Terminate;
end if;
end Propagate_Exception;
end Exception_Propagation;
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