1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2007, Free Software Foundation, Inc. --
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. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 pragma Style_Checks
(All_Checks
);
27 -- Turn off subprogram body ordering check. Subprograms are in order
28 -- by RM section rather than alphabetical
30 with Sinfo
.CN
; use Sinfo
.CN
;
35 -- Local functions, used only in this chapter
37 function P_Exception_Handler
return Node_Id
;
38 function P_Exception_Choice
return Node_Id
;
40 ---------------------------------
41 -- 11.1 Exception Declaration --
42 ---------------------------------
44 -- Parsed by P_Identifier_Declaration (3.3.1)
46 ------------------------------------------
47 -- 11.2 Handled Sequence Of Statements --
48 ------------------------------------------
50 -- HANDLED_SEQUENCE_OF_STATEMENTS ::=
51 -- SEQUENCE_OF_STATEMENTS
54 -- {EXCEPTION_HANDLER}]
56 -- Error_Recovery : Cannot raise Error_Resync
58 function P_Handled_Sequence_Of_Statements
return Node_Id
is
59 Handled_Stmt_Seq_Node
: Node_Id
;
62 Handled_Stmt_Seq_Node
:=
63 New_Node
(N_Handled_Sequence_Of_Statements
, Token_Ptr
);
65 (Handled_Stmt_Seq_Node
, P_Sequence_Of_Statements
(SS_Extm_Sreq
));
67 if Token
= Tok_Exception
then
68 Scan
; -- past EXCEPTION
69 Set_Exception_Handlers
70 (Handled_Stmt_Seq_Node
, Parse_Exception_Handlers
);
73 return Handled_Stmt_Seq_Node
;
74 end P_Handled_Sequence_Of_Statements
;
76 -----------------------------
77 -- 11.2 Exception Handler --
78 -----------------------------
80 -- EXCEPTION_HANDLER ::=
81 -- when [CHOICE_PARAMETER_SPECIFICATION :]
82 -- EXCEPTION_CHOICE {| EXCEPTION_CHOICE} =>
83 -- SEQUENCE_OF_STATEMENTS
85 -- CHOICE_PARAMETER_SPECIFICATION ::= DEFINING_IDENTIFIER
87 -- Error recovery: cannot raise Error_Resync
89 function P_Exception_Handler
return Node_Id
is
90 Scan_State
: Saved_Scan_State
;
91 Handler_Node
: Node_Id
;
92 Choice_Param_Node
: Node_Id
;
95 Handler_Node
:= New_Node
(N_Exception_Handler
, Token_Ptr
);
96 Set_Local_Raise_Statements
(Handler_Node
, No_Elist
);
99 -- Test for possible choice parameter present
101 if Token
= Tok_Identifier
then
102 Choice_Param_Node
:= Token_Node
;
103 Save_Scan_State
(Scan_State
); -- at identifier
104 Scan
; -- past identifier
106 if Token
= Tok_Colon
then
107 if Ada_Version
= Ada_83
then
108 Error_Msg_SP
("(Ada 83) choice parameter not allowed!");
112 Change_Identifier_To_Defining_Identifier
(Choice_Param_Node
);
113 Set_Choice_Parameter
(Handler_Node
, Choice_Param_Node
);
115 elsif Token
= Tok_Others
then
116 Error_Msg_AP
("missing "":""");
117 Change_Identifier_To_Defining_Identifier
(Choice_Param_Node
);
118 Set_Choice_Parameter
(Handler_Node
, Choice_Param_Node
);
121 Restore_Scan_State
(Scan_State
); -- to identifier
125 -- Loop through exception choices
127 Set_Exception_Choices
(Handler_Node
, New_List
);
130 Append
(P_Exception_Choice
, Exception_Choices
(Handler_Node
));
131 exit when Token
/= Tok_Vertical_Bar
;
132 Scan
; -- past vertical bar
136 Set_Statements
(Handler_Node
, P_Sequence_Of_Statements
(SS_Sreq_Whtm
));
138 end P_Exception_Handler
;
140 ------------------------------------------
141 -- 11.2 Choice Parameter Specification --
142 ------------------------------------------
144 -- Parsed by P_Exception_Handler (11.2)
146 ----------------------------
147 -- 11.2 Exception Choice --
148 ----------------------------
150 -- EXCEPTION_CHOICE ::= exception_NAME | others
152 -- Error recovery: cannot raise Error_Resync. If an error occurs, then the
153 -- scan pointer is advanced to the next arrow or vertical bar or semicolon.
155 function P_Exception_Choice
return Node_Id
is
158 if Token
= Tok_Others
then
160 return New_Node
(N_Others_Choice
, Prev_Token_Ptr
);
163 return P_Name
; -- exception name
170 end P_Exception_Choice
;
172 ---------------------------
173 -- 11.3 Raise Statement --
174 ---------------------------
176 -- RAISE_STATEMENT ::= raise [exception_NAME];
178 -- The caller has verified that the initial token is RAISE
180 -- Error recovery: can raise Error_Resync
182 function P_Raise_Statement
return Node_Id
is
183 Raise_Node
: Node_Id
;
186 Raise_Node
:= New_Node
(N_Raise_Statement
, Token_Ptr
);
189 if Token
/= Tok_Semicolon
then
190 Set_Name
(Raise_Node
, P_Name
);
193 if Token
= Tok_With
then
194 if Ada_Version
< Ada_05
then
195 Error_Msg_SC
("string expression in raise is Ada 2005 extension");
196 Error_Msg_SC
("\unit must be compiled with -gnat05 switch");
200 Set_Expression
(Raise_Node
, P_Expression
);
205 end P_Raise_Statement
;
207 ------------------------------
208 -- Parse_Exception_Handlers --
209 ------------------------------
211 -- This routine scans out a list of exception handlers appearing in a
215 -- EXCEPTION_HANDLER {EXCEPTION_HANDLER}
217 -- The caller has scanned out the EXCEPTION keyword
219 -- Control returns after scanning the last exception handler, presumably
220 -- at the keyword END, but this is not checked in this routine.
222 -- Error recovery: cannot raise Error_Resync
224 function Parse_Exception_Handlers
return List_Id
is
226 Handlers_List
: List_Id
;
229 Handlers_List
:= New_List
;
230 P_Pragmas_Opt
(Handlers_List
);
232 if Token
= Tok_End
then
233 Error_Msg_SC
("must have at least one exception handler!");
237 Handler
:= P_Exception_Handler
;
238 Append
(Handler
, Handlers_List
);
240 -- Note: no need to check for pragmas here. Although the
241 -- syntax officially allows them in this position, they
242 -- will have been swallowed up as part of the statement
243 -- sequence of the handler we just scanned out.
245 exit when Token
/= Tok_When
;
249 return Handlers_List
;
250 end Parse_Exception_Handlers
;