Fix unused warnings.
[official-gcc/graphite-test-results.git] / gcc / ada / a-exextr.adb
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1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- ADA.EXCEPTIONS.EXCEPTION_TRACES --
6 -- --
7 -- B o d y --
8 -- --
9 -- Copyright (C) 1992-2009, Free Software Foundation, Inc. --
10 -- --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. --
17 -- --
18 -- As a special exception under Section 7 of GPL version 3, you are granted --
19 -- additional permissions described in the GCC Runtime Library Exception, --
20 -- version 3.1, as published by the Free Software Foundation. --
21 -- --
22 -- You should have received a copy of the GNU General Public License and --
23 -- a copy of the GCC Runtime Library Exception along with this program; --
24 -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
25 -- <http://www.gnu.org/licenses/>. --
26 -- --
27 -- GNAT was originally developed by the GNAT team at New York University. --
28 -- Extensive contributions were provided by Ada Core Technologies Inc. --
29 -- --
30 ------------------------------------------------------------------------------
32 with Ada.Unchecked_Conversion;
34 pragma Warnings (Off);
35 with Ada.Exceptions.Last_Chance_Handler;
36 pragma Warnings (On);
37 -- Bring last chance handler into closure
39 separate (Ada.Exceptions)
40 package body Exception_Traces is
42 Nline : constant String := String'(1 => ASCII.LF);
43 -- Convenient shortcut
45 type Exception_Action is access procedure (E : Exception_Occurrence);
46 Global_Action : Exception_Action := null;
47 pragma Export
48 (Ada, Global_Action, "__gnat_exception_actions_global_action");
49 -- Global action, executed whenever an exception is raised. Changing the
50 -- export name must be coordinated with code in g-excact.adb.
52 Raise_Hook_Initialized : Boolean := False;
53 pragma Export
54 (Ada, Raise_Hook_Initialized, "__gnat_exception_actions_initialized");
56 procedure Last_Chance_Handler
57 (Except : Exception_Occurrence);
58 pragma Import (C, Last_Chance_Handler, "__gnat_last_chance_handler");
59 pragma No_Return (Last_Chance_Handler);
60 -- Users can replace the default version of this routine,
61 -- Ada.Exceptions.Last_Chance_Handler.
63 function To_Action is new Ada.Unchecked_Conversion
64 (Raise_Action, Exception_Action);
66 -----------------------
67 -- Local Subprograms --
68 -----------------------
70 procedure Notify_Exception (Excep : EOA; Is_Unhandled : Boolean);
71 -- Factorizes the common processing for Notify_Handled_Exception and
72 -- Notify_Unhandled_Exception. Is_Unhandled is set to True only in the
73 -- latter case because Notify_Handled_Exception may be called for an
74 -- actually unhandled occurrence in the Front-End-SJLJ case.
76 --------------------------------
77 -- Import Run-Time C Routines --
78 --------------------------------
80 -- The purpose of the following pragma Import is to ensure that we
81 -- generate appropriate subprogram descriptors for all C routines in
82 -- the standard GNAT library that can raise exceptions. This ensures
83 -- that the exception propagation can properly find these routines
85 pragma Propagate_Exceptions;
87 ----------------------
88 -- Notify_Exception --
89 ----------------------
91 procedure Notify_Exception (Excep : EOA; Is_Unhandled : Boolean) is
92 begin
93 -- Output the exception information required by the Exception_Trace
94 -- configuration. Take care not to output information about internal
95 -- exceptions.
97 -- ??? In the Front-End ZCX case, the traceback entries we have at this
98 -- point only include the ones we stored while walking up the stack *up
99 -- to the handler*. All the frames above the subprogram in which the
100 -- handler is found are missing.
102 if not Excep.Id.Not_Handled_By_Others
103 and then
104 (Exception_Trace = Every_Raise
105 or else (Exception_Trace = Unhandled_Raise and then Is_Unhandled))
106 then
107 -- Exception trace messages need to be protected when several tasks
108 -- can issue them at the same time.
110 Lock_Task.all;
111 To_Stderr (Nline);
113 if Is_Unhandled then
114 To_Stderr ("Unhandled ");
115 end if;
117 To_Stderr ("Exception raised");
118 To_Stderr (Nline);
119 To_Stderr (Tailored_Exception_Information (Excep.all));
120 Unlock_Task.all;
121 end if;
123 -- Call the user-specific actions
124 -- ??? We should presumably look at the reraise status here.
126 if Raise_Hook_Initialized
127 and then Exception_Data_Ptr (Excep.Id).Raise_Hook /= null
128 then
129 To_Action (Exception_Data_Ptr (Excep.Id).Raise_Hook) (Excep.all);
130 end if;
132 if Global_Action /= null then
133 Global_Action (Excep.all);
134 end if;
135 end Notify_Exception;
137 ------------------------------
138 -- Notify_Handled_Exception --
139 ------------------------------
141 procedure Notify_Handled_Exception is
142 begin
143 Notify_Exception (Get_Current_Excep.all, Is_Unhandled => False);
144 end Notify_Handled_Exception;
146 --------------------------------
147 -- Notify_Unhandled_Exception --
148 --------------------------------
150 procedure Notify_Unhandled_Exception is
151 Excep : constant EOA := Get_Current_Excep.all;
153 begin
154 -- Check whether there is any termination handler to be executed for
155 -- the environment task, and execute it if needed. Here we handle both
156 -- the Abnormal and Unhandled_Exception task termination. Normal
157 -- task termination routine is executed elsewhere (either in the
158 -- Task_Wrapper or in the Adafinal routine for the environment task).
160 Task_Termination_Handler.all (Excep.all);
162 Notify_Exception (Excep, Is_Unhandled => True);
163 Debug_Unhandled_Exception (SSL.Exception_Data_Ptr (Excep.Id));
164 end Notify_Unhandled_Exception;
166 -----------------------------------
167 -- Unhandled_Exception_Terminate --
168 -----------------------------------
170 procedure Unhandled_Exception_Terminate is
171 Excep : constant EOA := Save_Occurrence (Get_Current_Excep.all.all);
172 -- This occurrence will be used to display a message after finalization.
173 -- It is necessary to save a copy here, or else the designated value
174 -- could be overwritten if an exception is raised during finalization
175 -- (even if that exception is caught).
177 begin
178 Last_Chance_Handler (Excep.all);
179 end Unhandled_Exception_Terminate;
181 ------------------------------------
182 -- Handling GNAT.Exception_Traces --
183 ------------------------------------
185 -- The bulk of exception traces output is centralized in Notify_Exception,
186 -- for both the Handled and Unhandled cases. Extra task specific output is
187 -- triggered in the task wrapper for unhandled occurrences in tasks. It is
188 -- not performed in this unit to avoid dragging dependencies against the
189 -- tasking units here.
191 -- We used to rely on the output performed by Unhanded_Exception_Terminate
192 -- for the case of an unhandled occurrence in the environment thread, and
193 -- the task wrapper was responsible for the whole output in the tasking
194 -- case.
196 -- This initial scheme had a drawback: the output from Terminate only
197 -- occurs after finalization is done, which means possibly never if some
198 -- tasks keep hanging around.
200 -- The first "presumably obvious" fix consists in moving the Terminate
201 -- output before the finalization. It has not been retained because it
202 -- introduces annoying changes in output orders when the finalization
203 -- itself issues outputs, this also in "regular" cases not resorting to
204 -- Exception_Traces.
206 -- Today's solution has the advantage of simplicity and better isolates
207 -- the Exception_Traces machinery.
209 -- It currently outputs the information about unhandled exceptions twice
210 -- in the environment thread, once in the notification routine and once in
211 -- the termination routine. Avoiding the second output is possible but so
212 -- far has been considered undesirable. It would mean changing the order
213 -- of outputs between the two runs with or without exception traces, while
214 -- it seems preferable to only have additional outputs in the former
215 -- case.
217 end Exception_Traces;