summaryrefslogtreecommitdiffstats
path: root/gcc/ada/sem_prag.ads
blob: 492eb9f779f83417e6d0d65169b29c626d5d03ae (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
------------------------------------------------------------------------------
--                                                                          --
--                         GNAT COMPILER COMPONENTS                         --
--                                                                          --
--                             S E M _ P R A G                              --
--                                                                          --
--                                 S p e c                                  --
--                                                                          --
--          Copyright (C) 1992-2013, 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 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.  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 COPYING3.  If not, go to --
-- http://www.gnu.org/licenses for a complete copy of the license.          --
--                                                                          --
-- GNAT was originally developed  by the GNAT team at  New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc.      --
--                                                                          --
------------------------------------------------------------------------------

--  Pragma handling is isolated in a separate package
--  (logically this processing belongs in chapter 4)

with Namet;  use Namet;
with Snames; use Snames;
with Types;  use Types;

package Sem_Prag is

   --  The following table lists all the implementation-defined pragmas that
   --  may apply to a body stub (no language defined pragmas apply). The table
   --  should be synchronized with Aspect_On_Body_Or_Stub_OK in unit Aspects if
   --  the pragmas below implement an aspect.

   Pragma_On_Body_Or_Stub_OK : constant array (Pragma_Id) of Boolean :=
     (Pragma_Refined_Post => True,
      Pragma_Refined_Pre  => True,
      Pragma_SPARK_Mode   => True,
      Pragma_Warnings     => True,
      others              => False);

   -----------------
   -- Subprograms --
   -----------------

   procedure Analyze_Pragma (N : Node_Id);
   --  Analyze procedure for pragma reference node N

   procedure Analyze_Contract_Cases_In_Decl_Part (N : Node_Id);
   --  Perform full analysis and expansion of delayed pragma Contract_Cases

   procedure Analyze_Depends_In_Decl_Part (N : Node_Id);
   --  Perform full analysis of delayed pragma Depends

   procedure Analyze_Global_In_Decl_Part (N : Node_Id);
   --  Perform full analysis of delayed pragma Global

   procedure Analyze_PPC_In_Decl_Part (N : Node_Id; S : Entity_Id);
   --  Special analyze routine for precondition/postcondition pragma that
   --  appears within a declarative part where the pragma is associated
   --  with a subprogram specification. N is the pragma node, and S is the
   --  entity for the related subprogram. This procedure does a preanalysis
   --  of the expressions in the pragma as "spec expressions" (see section
   --  in Sem "Handling of Default and Per-Object Expressions...").

   procedure Analyze_Test_Case_In_Decl_Part (N : Node_Id; S : Entity_Id);
   --  Special analyze routine for contract-case and test-case pragmas that
   --  appears within a declarative part where the pragma is associated with
   --  a subprogram specification. N is the pragma node, and S is the entity
   --  for the related subprogram. This procedure does a preanalysis of the
   --  expressions in the pragma as "spec expressions" (see section in Sem
   --  "Handling of Default and Per-Object Expressions...").

   procedure Check_Applicable_Policy (N : Node_Id);
   --  N is either an N_Aspect or an N_Pragma node. There are two cases. If
   --  the name of the aspect or pragma is not one of those recognized as
   --  an assertion kind by an Assertion_Policy pragma, then the call has
   --  no effect. Note that in the case of a pragma derived from an aspect,
   --  the name we use for the purpose of this procedure is the aspect name,
   --  which may be different from the pragma name (e.g. Precondition for
   --  Pre aspect). In addition, 'Class aspects are recognized (and the
   --  corresponding special names used in the processing).
   --
   --  If the name is a valid assertion kind name, then the Check_Policy pragma
   --  chain is checked for a matching entry (or for an Assertion entry which
   --  matches all possibilities). If a matching entry is found then the policy
   --  is checked. If it is On or Check, then the Is_Checked flag is set in
   --  the aspect or pragma node. If it is Off, Ignore, or Disable, then the
   --  Is_Ignored flag is set in the aspect or pragma node. Additionally for
   --  policy Disable, the Is_Disabled flag is set.
   --
   --  If no matching Check_Policy pragma is found then the effect depends on
   --  whether -gnata was used, if so, then the call has no effect, otherwise
   --  Is_Ignored (but not Is_Disabled) is set True.

   function Delay_Config_Pragma_Analyze (N : Node_Id) return Boolean;
   --  N is a pragma appearing in a configuration pragma file. Most such
   --  pragmas are analyzed when the file is read, before parsing and analyzing
   --  the main unit. However, the analysis of certain pragmas results in
   --  adding information to the compiled main unit, and this cannot be done
   --  till the main unit is processed. Such pragmas return True from this
   --  function and in Frontend pragmas where Delay_Config_Pragma_Analyze is
   --  True have their analysis delayed until after the main program is parsed
   --  and analyzed.

   function Get_SPARK_Mode_Id (N : Node_Id) return SPARK_Mode_Id;
   --  Given a pragma SPARK_Mode node, return the corresponding mode id

   procedure Initialize;
   --  Initializes data structures used for pragma processing. Must be called
   --  before analyzing each new main source program.

   function Is_Config_Static_String (Arg : Node_Id) return Boolean;
   --  This is called for a configuration pragma that requires either string
   --  literal or a concatenation of string literals. We cannot use normal
   --  static string processing because it is too early in the case of the
   --  pragma appearing in a configuration pragmas file. If Arg is of an
   --  appropriate form, then this call obtains the string (doing any necessary
   --  concatenations) and places it in Name_Buffer, setting Name_Len to its
   --  length, and then returns True. If it is not of the correct form, then an
   --  appropriate error message is posted, and False is returned.

   function Is_Elaboration_SPARK_Mode (N : Node_Id) return Boolean;
   --  Determine whether pragma SPARK_Mode appears in the statement part of a
   --  package body.

   function Is_Non_Significant_Pragma_Reference (N : Node_Id) return Boolean;
   --  The node N is a node for an entity and the issue is whether the
   --  occurrence is a reference for the purposes of giving warnings about
   --  unreferenced variables. This function returns True if the reference is
   --  not a reference from this point of view (e.g. the occurrence in a pragma
   --  Pack) and False if it is a real reference (e.g. the occurrence in a
   --  pragma Export);

   function Is_Pragma_String_Literal (Par : Node_Id) return Boolean;
   --  Given an N_Pragma_Argument_Association node, Par, which has the form of
   --  an operator symbol, determines whether or not it should be treated as an
   --  string literal. This is called by Sem_Ch6.Analyze_Operator_Symbol. If
   --  True is returned, the argument is converted to a string literal. If
   --  False is returned, then the argument is treated as an entity reference
   --  to the operator.

   function Is_Private_SPARK_Mode (N : Node_Id) return Boolean;
   --  Determine whether pragma SPARK_Mode appears in the private part of a
   --  package.

   function Is_Valid_Assertion_Kind (Nam : Name_Id) return Boolean;
   --  Returns True if Nam is one of the names recognized as a valid assertion
   --  kind by the Assertion_Policy pragma. Note that the 'Class cases are
   --  represented by the corresponding special names Name_uPre, Name_uPost,
   --  Name_uInviarnat, and Name_uType_Invariant (_Pre, _Post, _Invariant,
   --  and _Type_Invariant).

   procedure Make_Aspect_For_PPC_In_Gen_Sub_Decl (Decl : Node_Id);
   --  This routine makes aspects from precondition or postcondition pragmas
   --  that appear within a generic subprogram declaration. Decl is the generic
   --  subprogram declaration node. Note that the aspects are attached to the
   --  generic copy and also to the orginal tree.

   procedure Process_Compilation_Unit_Pragmas (N : Node_Id);
   --  Called at the start of processing compilation unit N to deal with any
   --  special issues regarding pragmas. In particular, we have to deal with
   --  Suppress_All at this stage, since it can appear after the unit instead
   --  of before (actually we allow it to appear anywhere).

   procedure Relocate_Pragmas_To_Body
     (Subp_Body   : Node_Id;
      Target_Body : Node_Id := Empty);
   --  Resocate all pragmas that follow and apply to subprogram body Subp_Body
   --  to its own declaration list. Candidate pragmas are classified in table
   --  Pragma_On_Body_Or_Stub_OK. If Target_Body is set, the pragma are moved
   --  to the declarations of Target_Body. This formal should be set when
   --  dealing with subprogram body stubs or expression functions.

   procedure Set_Encoded_Interface_Name (E : Entity_Id; S : Node_Id);
   --  This routine is used to set an encoded interface name. The node S is an
   --  N_String_Literal node for the external name to be set, and E is an
   --  entity whose Interface_Name field is to be set. In the normal case where
   --  S contains a name that is a valid C identifier, then S is simply set as
   --  the value of the Interface_Name. Otherwise it is encoded. See the body
   --  for details of the encoding. This encoding is only done on VMS systems,
   --  since it seems pretty silly, but is needed to pass some dubious tests in
   --  the test suite.

end Sem_Prag;
OpenPOWER on IntegriCloud