|
111
|
1 ------------------------------------------------------------------------------
|
|
|
2 -- --
|
|
|
3 -- GNAT COMPILER COMPONENTS --
|
|
|
4 -- --
|
|
|
5 -- S E M _ C H 8 --
|
|
|
6 -- --
|
|
|
7 -- S p e c --
|
|
|
8 -- --
|
|
145
|
9 -- Copyright (C) 1992-2019, Free Software Foundation, Inc. --
|
|
111
|
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. 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. --
|
|
|
20 -- --
|
|
|
21 -- GNAT was originally developed by the GNAT team at New York University. --
|
|
|
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
|
|
|
23 -- --
|
|
|
24 ------------------------------------------------------------------------------
|
|
|
25
|
|
|
26 with Types; use Types;
|
|
|
27 package Sem_Ch8 is
|
|
|
28
|
|
|
29 -----------------------------------
|
|
|
30 -- Handling extensions of System --
|
|
|
31 -----------------------------------
|
|
|
32
|
|
|
33 -- For targets that define a much larger System package than given in
|
|
|
34 -- the RM, we use a child package containing additional declarations,
|
|
|
35 -- which is loaded when needed, and whose entities are conceptually
|
|
|
36 -- within System itself. The presence of this auxiliary package is
|
|
|
37 -- controlled with the pragma Extend_System. The following variable
|
|
|
38 -- holds the entity of the auxiliary package, to simplify the special
|
|
|
39 -- visibility rules that apply to it.
|
|
|
40
|
|
|
41 System_Aux_Id : Entity_Id := Empty;
|
|
|
42
|
|
|
43 -----------------
|
|
|
44 -- Subprograms --
|
|
|
45 -----------------
|
|
|
46
|
|
|
47 procedure Analyze_Exception_Renaming (N : Node_Id);
|
|
|
48 procedure Analyze_Expanded_Name (N : Node_Id);
|
|
|
49 procedure Analyze_Generic_Function_Renaming (N : Node_Id);
|
|
|
50 procedure Analyze_Generic_Package_Renaming (N : Node_Id);
|
|
|
51 procedure Analyze_Generic_Procedure_Renaming (N : Node_Id);
|
|
|
52 procedure Analyze_Object_Renaming (N : Node_Id);
|
|
|
53 procedure Analyze_Package_Renaming (N : Node_Id);
|
|
|
54 procedure Analyze_Subprogram_Renaming (N : Node_Id);
|
|
|
55
|
|
|
56 procedure Analyze_Use_Package (N : Node_Id; Chain : Boolean := True);
|
|
|
57 -- Analyze a use package clause and control (through the Chain parameter)
|
|
|
58 -- whether to add N to the use clause chain for the name denoted within
|
|
|
59 -- use clause N in case we are reanalyzing a use clause because of stack
|
|
|
60 -- manipulation.
|
|
|
61
|
|
|
62 procedure Analyze_Use_Type (N : Node_Id; Chain : Boolean := True);
|
|
|
63 -- Similar to Analyze_Use_Package except the Chain parameter applies to the
|
|
|
64 -- type within N's subtype mark Current_Use_Clause.
|
|
|
65
|
|
|
66 procedure End_Scope;
|
|
|
67 -- Called at end of scope. On exit from blocks and bodies (subprogram,
|
|
|
68 -- package, task, and protected bodies), the name of the current scope
|
|
|
69 -- must be removed from the scope stack, and the local entities must be
|
|
|
70 -- removed from their homonym chains. On exit from record declarations,
|
|
|
71 -- from package specifications, and from tasks and protected type
|
|
|
72 -- specifications, more specialized procedures are invoked.
|
|
|
73
|
|
|
74 procedure End_Use_Clauses (Clause : Node_Id);
|
|
|
75 -- Invoked on scope exit, to undo the effect of local use clauses. Clause
|
|
|
76 -- is the first use-clause of a scope being exited. This can be the current
|
|
|
77 -- scope, or some enclosing scopes when building a clean environment to
|
|
|
78 -- compile an instance body for inlining.
|
|
|
79
|
|
|
80 procedure End_Use_Package (N : Node_Id);
|
|
|
81 procedure End_Use_Type (N : Node_Id);
|
|
|
82 -- Subsidiaries of End_Use_Clauses. Also called directly for use clauses
|
|
|
83 -- appearing in context clauses.
|
|
|
84
|
|
145
|
85 procedure Find_Direct_Name
|
|
|
86 (N : Node_Id;
|
|
|
87 Errors_OK : Boolean := True;
|
|
|
88 Marker_OK : Boolean := True;
|
|
|
89 Reference_OK : Boolean := True);
|
|
111
|
90 -- Given a direct name (Identifier or Operator_Symbol), this routine scans
|
|
|
91 -- the homonym chain for the name, searching for corresponding visible
|
|
|
92 -- entities to find the referenced entity (or in the case of overloading,
|
|
|
93 -- one candidate interpretation). On return, the Entity and Etype fields
|
|
|
94 -- are set. In the non-overloaded case, these are the correct entries.
|
|
|
95 -- In the overloaded case, the flag Is_Overloaded is set, Etype and Entity
|
|
|
96 -- refer to an arbitrary element of the overloads set, and the appropriate
|
|
|
97 -- entries have been added to the overloads table entry for the node. The
|
|
|
98 -- overloading will be disambiguated during type resolution.
|
|
|
99 --
|
|
|
100 -- Note, when this is called during semantic analysis in the overloaded
|
|
|
101 -- case, the entity set will be the most recently declared homonym. In
|
|
|
102 -- particular, the caller may follow the homonym chain checking for all
|
|
|
103 -- entries in the current scope, and that will give all homonyms that are
|
|
|
104 -- declared before the point of call in the current scope. This is useful
|
|
|
105 -- for example in the processing for pragma Inline.
|
|
145
|
106 --
|
|
|
107 -- Flag Errors_OK should be set when error diagnostics are desired. Flag
|
|
|
108 -- Marker_OK should be set when a N_Variable_Reference_Marker needs to be
|
|
|
109 -- generated for a SPARK object in order to detect elaboration issues. Flag
|
|
|
110 -- Reference_OK should be set when N must generate a cross reference.
|
|
111
|
111
|
|
|
112 procedure Find_Selected_Component (N : Node_Id);
|
|
|
113 -- Resolve various cases of selected components, recognize expanded names
|
|
|
114
|
|
|
115 procedure Find_Type (N : Node_Id);
|
|
|
116 -- Perform name resolution, and verify that the name found is that of a
|
|
|
117 -- type. On return the Entity and Etype fields of the node N are set
|
|
|
118 -- appropriately. If it is an incomplete type whose full declaration has
|
|
|
119 -- been seen, they are set to the entity in the full declaration. If it
|
|
|
120 -- is an incomplete type associated with an interface visible through a
|
|
|
121 -- limited-with clause, whose full declaration has been seen, they are
|
|
|
122 -- set to the entity in the full declaration. Similarly, if the type is
|
|
|
123 -- private, it has received a full declaration, and we are in the private
|
|
|
124 -- part or body of the package, then the two fields are set to the entity
|
|
|
125 -- of the full declaration as well. This procedure also has special
|
|
|
126 -- processing for 'Class attribute references.
|
|
|
127
|
|
|
128 function Has_Loop_In_Inner_Open_Scopes (S : Entity_Id) return Boolean;
|
|
|
129 -- S is the entity of an open scope. This function determines if there is
|
|
|
130 -- an inner scope of S which is a loop (i.e. it appears somewhere in the
|
|
|
131 -- scope stack after S).
|
|
|
132
|
|
|
133 function In_Open_Scopes (S : Entity_Id) return Boolean;
|
|
|
134 -- S is the entity of a scope. This function determines if this scope is
|
|
|
135 -- currently open (i.e. it appears somewhere in the scope stack).
|
|
|
136
|
|
|
137 procedure Initialize;
|
|
|
138 -- Initializes data structures used for visibility analysis. Must be
|
|
|
139 -- called before analyzing each new main source program.
|
|
|
140
|
|
|
141 procedure Install_Use_Clauses
|
|
|
142 (Clause : Node_Id;
|
|
|
143 Force_Installation : Boolean := False);
|
|
|
144 -- Applies the use clauses appearing in a given declarative part,
|
|
|
145 -- when the corresponding scope has been placed back on the scope
|
|
|
146 -- stack after unstacking to compile a different context (subunit or
|
|
|
147 -- parent of generic body). Force_Installation is used when called from
|
|
|
148 -- Analyze_Subunit.Re_Install_Use_Clauses to insure that, after the
|
|
|
149 -- analysis of the subunit, the parent's environment is again identical.
|
|
|
150
|
|
|
151 procedure Mark_Use_Clauses (Id : Node_Or_Entity_Id);
|
|
|
152 -- Mark a given entity or node Id's relevant use clauses as effective,
|
|
|
153 -- including redundant ones and ones outside of the current scope.
|
|
|
154
|
|
|
155 procedure Push_Scope (S : Entity_Id);
|
|
|
156 -- Make new scope stack entry, pushing S, the entity for a scope onto the
|
|
|
157 -- top of the scope table. The current setting of the scope suppress flags
|
|
|
158 -- is saved for restoration on exit.
|
|
|
159
|
|
|
160 procedure Pop_Scope;
|
|
|
161 -- Remove top entry from scope stack, restoring the saved setting of the
|
|
|
162 -- scope suppress flags.
|
|
|
163
|
|
|
164 function Present_System_Aux (N : Node_Id := Empty) return Boolean;
|
|
|
165 -- Return True if the auxiliary system file has been successfully loaded.
|
|
|
166 -- Otherwise attempt to load it, using the name supplied by a previous
|
|
|
167 -- Extend_System pragma, and report on the success of the load. If N is
|
|
|
168 -- present, it is a selected component whose prefix is System, or else a
|
|
|
169 -- with-clause on system. N is absent when the function is called to find
|
|
|
170 -- the visibility of implicit operators.
|
|
|
171
|
|
|
172 function Save_Scope_Stack
|
|
|
173 (Handle_Use : Boolean := True) return Elist_Id;
|
|
|
174 procedure Restore_Scope_Stack
|
|
|
175 (List : Elist_Id;
|
|
|
176 Handle_Use : Boolean := True);
|
|
|
177 -- These two subprograms are called from Semantics, when a unit U1 is to
|
|
|
178 -- be compiled in the course of the compilation of another unit U2. This
|
|
|
179 -- happens whenever Rtsfind is called. U1, the unit retrieved by Rtsfind,
|
|
|
180 -- must be compiled in its own context, and the current scope stack
|
|
|
181 -- containing U2 and local scopes must be made unreachable. This is
|
|
|
182 -- achieved using a call to Save_Scope_Stack. On return, the contents
|
|
|
183 -- of the scope stack must be made accessible again with a call to
|
|
|
184 -- Restore_Scope_Stack.
|
|
|
185 --
|
|
|
186 -- The flag Handle_Use indicates whether local use clauses must be removed
|
|
|
187 -- or installed. In the case of inlining of instance bodies, the visibility
|
|
|
188 -- handling is done fully in Inline_Instance_Body, and use clauses are
|
|
|
189 -- handled there. Save_Scope_Stack returns the list of entities which have
|
|
|
190 -- been temporarily removed from visibility; that list must be passed to
|
|
|
191 -- Restore_Scope_Stack to restore their visibility.
|
|
|
192
|
|
|
193 procedure Set_Use (L : List_Id);
|
|
|
194 -- Find use clauses that are declarative items in a package declaration
|
|
|
195 -- and set the potentially use-visible flags of imported entities before
|
|
|
196 -- analyzing the corresponding package body.
|
|
|
197
|
|
|
198 procedure Update_Use_Clause_Chain;
|
|
|
199 -- Called at the end of a declarative region to detect unused use type
|
|
|
200 -- clauses and maintain the Current_Use_Clause for type entities.
|
|
|
201
|
|
|
202 procedure ws;
|
|
|
203 -- Debugging routine for use in gdb: dump all entities on scope stack
|
|
|
204
|
|
|
205 procedure we (S : Entity_Id);
|
|
|
206 -- Debugging routine for use in gdb: dump all entities in given scope
|
|
|
207
|
|
|
208 end Sem_Ch8;
|
