1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2006, 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 2, 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 COPYING. If not, write --
19 -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
20 -- Boston, MA 02110-1301, USA. --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
25 ------------------------------------------------------------------------------
27 pragma Style_Checks (All_Checks);
28 -- Turn off subprogram body ordering check. Subprograms are in order
29 -- by RM section rather than alphabetical
31 with Sinfo.CN; use Sinfo.CN;
36 -- Local functions, used only in this chapter
38 function P_Exception_Handler return Node_Id;
39 function P_Exception_Choice return Node_Id;
41 ---------------------------------
42 -- 11.1 Exception Declaration --
43 ---------------------------------
45 -- Parsed by P_Identifier_Declaration (3.3.1)
47 ------------------------------------------
48 -- 11.2 Handled Sequence Of Statements --
49 ------------------------------------------
51 -- HANDLED_SEQUENCE_OF_STATEMENTS ::=
52 -- SEQUENCE_OF_STATEMENTS
55 -- {EXCEPTION_HANDLER}]
57 -- Error_Recovery : Cannot raise Error_Resync
59 function P_Handled_Sequence_Of_Statements return Node_Id is
60 Handled_Stmt_Seq_Node : Node_Id;
63 Handled_Stmt_Seq_Node :=
64 New_Node (N_Handled_Sequence_Of_Statements, Token_Ptr);
66 (Handled_Stmt_Seq_Node, P_Sequence_Of_Statements (SS_Extm_Sreq));
68 if Token = Tok_Exception then
69 Scan; -- past EXCEPTION
70 Set_Exception_Handlers
71 (Handled_Stmt_Seq_Node, Parse_Exception_Handlers);
74 return Handled_Stmt_Seq_Node;
75 end P_Handled_Sequence_Of_Statements;
77 -----------------------------
78 -- 11.2 Exception Handler --
79 -----------------------------
81 -- EXCEPTION_HANDLER ::=
82 -- when [CHOICE_PARAMETER_SPECIFICATION :]
83 -- EXCEPTION_CHOICE {| EXCEPTION_CHOICE} =>
84 -- SEQUENCE_OF_STATEMENTS
86 -- CHOICE_PARAMETER_SPECIFICATION ::= DEFINING_IDENTIFIER
88 -- Error recovery: cannot raise Error_Resync
90 function P_Exception_Handler return Node_Id is
91 Scan_State : Saved_Scan_State;
92 Handler_Node : Node_Id;
93 Choice_Param_Node : Node_Id;
96 Handler_Node := New_Node (N_Exception_Handler, Token_Ptr);
97 Set_Local_Raise_Statements (Handler_Node, No_Elist);
100 -- Test for possible choice parameter present
102 if Token = Tok_Identifier then
103 Choice_Param_Node := Token_Node;
104 Save_Scan_State (Scan_State); -- at identifier
105 Scan; -- past identifier
107 if Token = Tok_Colon then
108 if Ada_Version = Ada_83 then
109 Error_Msg_SP ("(Ada 83) choice parameter not allowed!");
113 Change_Identifier_To_Defining_Identifier (Choice_Param_Node);
114 Set_Choice_Parameter (Handler_Node, Choice_Param_Node);
116 elsif Token = Tok_Others then
117 Error_Msg_AP ("missing "":""");
118 Change_Identifier_To_Defining_Identifier (Choice_Param_Node);
119 Set_Choice_Parameter (Handler_Node, Choice_Param_Node);
122 Restore_Scan_State (Scan_State); -- to identifier
126 -- Loop through exception choices
128 Set_Exception_Choices (Handler_Node, New_List);
131 Append (P_Exception_Choice, Exception_Choices (Handler_Node));
132 exit when Token /= Tok_Vertical_Bar;
133 Scan; -- past vertical bar
137 Set_Statements (Handler_Node, P_Sequence_Of_Statements (SS_Sreq_Whtm));
139 end P_Exception_Handler;
141 ------------------------------------------
142 -- 11.2 Choice Parameter Specification --
143 ------------------------------------------
145 -- Parsed by P_Exception_Handler (11.2)
147 ----------------------------
148 -- 11.2 Exception Choice --
149 ----------------------------
151 -- EXCEPTION_CHOICE ::= exception_NAME | others
153 -- Error recovery: cannot raise Error_Resync. If an error occurs, then the
154 -- scan pointer is advanced to the next arrow or vertical bar or semicolon.
156 function P_Exception_Choice return Node_Id is
159 if Token = Tok_Others then
161 return New_Node (N_Others_Choice, Prev_Token_Ptr);
164 return P_Name; -- exception name
171 end P_Exception_Choice;
173 ---------------------------
174 -- 11.3 Raise Statement --
175 ---------------------------
177 -- RAISE_STATEMENT ::= raise [exception_NAME];
179 -- The caller has verified that the initial token is RAISE
181 -- Error recovery: can raise Error_Resync
183 function P_Raise_Statement return Node_Id is
184 Raise_Node : Node_Id;
187 Raise_Node := New_Node (N_Raise_Statement, Token_Ptr);
190 if Token /= Tok_Semicolon then
191 Set_Name (Raise_Node, P_Name);
194 if Token = Tok_With then
195 if Ada_Version < Ada_05 then
196 Error_Msg_SC ("string expression in raise is Ada 2005 extension");
197 Error_Msg_SC ("\unit must be compiled with -gnat05 switch");
201 Set_Expression (Raise_Node, P_Expression);
206 end P_Raise_Statement;
208 ------------------------------
209 -- Parse_Exception_Handlers --
210 ------------------------------
212 -- This routine scans out a list of exception handlers appearing in a
216 -- EXCEPTION_HANDLER {EXCEPTION_HANDLER}
218 -- The caller has scanned out the EXCEPTION keyword
220 -- Control returns after scanning the last exception handler, presumably
221 -- at the keyword END, but this is not checked in this routine.
223 -- Error recovery: cannot raise Error_Resync
225 function Parse_Exception_Handlers return List_Id is
227 Handlers_List : List_Id;
230 Handlers_List := New_List;
231 P_Pragmas_Opt (Handlers_List);
233 if Token = Tok_End then
234 Error_Msg_SC ("must have at least one exception handler!");
238 Handler := P_Exception_Handler;
239 Append (Handler, Handlers_List);
241 -- Note: no need to check for pragmas here. Although the
242 -- syntax officially allows them in this position, they
243 -- will have been swallowed up as part of the statement
244 -- sequence of the handler we just scanned out.
246 exit when Token /= Tok_When;
250 return Handlers_List;
251 end Parse_Exception_Handlers;