2003-12-26 Guilhem Lavaux <guilhem@kaffe.org>
[official-gcc.git] / gcc / ada / sem_ch3.ads
blob3cae7d3d739647154bc0d7fff5c7a706333a0d42
1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- S E M _ C H 3 --
6 -- --
7 -- S p e c --
8 -- --
9 -- Copyright (C) 1992-2003 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 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, 59 Temple Place - Suite 330, Boston, --
20 -- MA 02111-1307, USA. --
21 -- --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 -- --
25 ------------------------------------------------------------------------------
27 with Nlists; use Nlists;
28 with Types; use Types;
30 package Sem_Ch3 is
31 procedure Analyze_Component_Declaration (N : Node_Id);
32 procedure Analyze_Incomplete_Type_Decl (N : Node_Id);
33 procedure Analyze_Itype_Reference (N : Node_Id);
34 procedure Analyze_Number_Declaration (N : Node_Id);
35 procedure Analyze_Object_Declaration (N : Node_Id);
36 procedure Analyze_Others_Choice (N : Node_Id);
37 procedure Analyze_Private_Extension_Declaration (N : Node_Id);
38 procedure Analyze_Subtype_Declaration (N : Node_Id);
39 procedure Analyze_Subtype_Indication (N : Node_Id);
40 procedure Analyze_Type_Declaration (N : Node_Id);
41 procedure Analyze_Variant_Part (N : Node_Id);
43 function Access_Definition
44 (Related_Nod : Node_Id;
45 N : Node_Id) return Entity_Id;
46 -- An access definition defines a general access type for a formal
47 -- parameter. The procedure is called when processing formals, when
48 -- the current scope is the subprogram. The Implicit type is attached
49 -- to the Related_Nod put into the enclosing scope, so that the only
50 -- entities defined in the spec are the formals themselves.
52 procedure Access_Subprogram_Declaration
53 (T_Name : Entity_Id;
54 T_Def : Node_Id);
55 -- The subprogram specification yields the signature of an implicit
56 -- type, whose Ekind is Access_Subprogram_Type. This implicit type is
57 -- the designated type of the declared access type. In subprogram calls,
58 -- the signature of the implicit type works like the profile of a regular
59 -- subprogram.
61 procedure Analyze_Declarations (L : List_Id);
62 -- Called to analyze a list of declarations (in what context ???). Also
63 -- performs necessary freezing actions (more description needed ???)
65 procedure Analyze_Per_Use_Expression (N : Node_Id; T : Entity_Id);
66 -- Default and per object expressions do not freeze their components,
67 -- and must be analyzed and resolved accordingly. The analysis is
68 -- done by calling the Pre_Analyze_And_Resolve routine and setting
69 -- the global In_Default_Expression flag. See the documentation section
70 -- entitled "Handling of Default and Per-Object Expressions" in sem.ads
71 -- for details. N is the expression to be analyzed, T is the expected type.
73 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id);
74 -- Process an array type declaration. If the array is constrained, we
75 -- create an implicit parent array type, with the same index types and
76 -- component type.
78 procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id);
79 -- Process an access type declaration
81 procedure Check_Abstract_Overriding (T : Entity_Id);
82 -- Check that all abstract subprograms inherited from T's parent type
83 -- have been overridden as required, and that nonabstract subprograms
84 -- have not been incorrectly overridden with an abstract subprogram.
86 procedure Check_Aliased_Component_Types (T : Entity_Id);
87 -- Given an array type or record type T, check that if the type is
88 -- nonlimited, then the nominal subtype of any components of T
89 -- that have discriminants must be constrained.
91 procedure Check_Completion (Body_Id : Node_Id := Empty);
92 -- At the end of a declarative part, verify that all entities that
93 -- require completion have received one. If Body_Id is absent, the
94 -- error indicating a missing completion is placed on the declaration
95 -- that needs completion. If Body_Id is present, it is the defining
96 -- identifier of a package body, and errors are posted on that node,
97 -- rather than on the declarations that require completion in the package
98 -- declaration.
100 procedure Derive_Subprogram
101 (New_Subp : in out Entity_Id;
102 Parent_Subp : Entity_Id;
103 Derived_Type : Entity_Id;
104 Parent_Type : Entity_Id;
105 Actual_Subp : Entity_Id := Empty);
106 -- Derive the subprogram Parent_Subp from Parent_Type, and replace the
107 -- subsidiary subtypes with the derived type to build the specification
108 -- of the inherited subprogram (returned in New_Subp). For tagged types,
109 -- the derived subprogram is aliased to that of the actual (in the
110 -- case where Actual_Subp is nonempty) rather than to the corresponding
111 -- subprogram of the parent type.
113 procedure Derive_Subprograms
114 (Parent_Type : Entity_Id;
115 Derived_Type : Entity_Id;
116 Generic_Actual : Entity_Id := Empty);
117 -- To complete type derivation, collect or retrieve the primitive
118 -- operations of the parent type, and replace the subsidiary subtypes
119 -- with the derived type, to build the specs of the inherited ops.
120 -- For generic actuals, the mapping of the primitive operations to those
121 -- of the parent type is also done by rederiving the operations within
122 -- the instance. For tagged types, the derived subprograms are aliased to
123 -- those of the actual, not those of the ancestor.
125 function Find_Type_Name (N : Node_Id) return Entity_Id;
126 -- Enter the identifier in a type definition, or find the entity already
127 -- declared, in the case of the full declaration of an incomplete or
128 -- private type.
130 function Get_Discriminant_Value
131 (Discriminant : Entity_Id;
132 Typ_For_Constraint : Entity_Id;
133 Constraint : Elist_Id) return Node_Id;
134 -- ??? MORE DOCUMENTATION
135 -- Given a discriminant somewhere in the Typ_For_Constraint tree
136 -- and a Constraint, return the value of that discriminant.
138 function Is_Visible_Component (C : Entity_Id) return Boolean;
139 -- Determines if a record component C is visible in the present context.
140 -- Note that even though component C could appear in the entity chain
141 -- of a record type, C may not be visible in the current context. For
142 -- instance, C may be a component inherited in the full view of a private
143 -- extension which is not visible in the current context.
145 procedure Make_Index
146 (I : Node_Id;
147 Related_Nod : Node_Id;
148 Related_Id : Entity_Id := Empty;
149 Suffix_Index : Nat := 1);
150 -- Process an index that is given in an array declaration, an entry
151 -- family declaration or a loop iteration. The index is given by an
152 -- index declaration (a 'box'), or by a discrete range. The later can
153 -- be the name of a discrete type, or a subtype indication.
154 -- Related_Nod is the node where the potential generated implicit types
155 -- will be inserted. The 2 last parameters are used for creating the name.
157 procedure Make_Class_Wide_Type (T : Entity_Id);
158 -- A Class_Wide_Type is created for each tagged type definition. The
159 -- attributes of a class wide type are inherited from those of the type
160 -- T. If T is introduced by a private declaration, the corresponding
161 -- class wide type is created at the same time, and therefore there is
162 -- a private and a full declaration for the class wide type type as well.
164 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id);
165 -- Process some semantic actions when the full view of a private type is
166 -- encountered and analyzed. The first action is to create the full views
167 -- of the dependant private subtypes. The second action is to recopy the
168 -- primitive operations of the private view (in the tagged case).
169 -- N is the N_Full_Type_Declaration node.
171 -- Full_T is the full view of the type whose full declaration is in N.
173 -- Priv_T is the private view of the type whose full declaration is in N.
175 procedure Process_Range_Expr_In_Decl
176 (R : Node_Id;
177 T : Entity_Id;
178 Check_List : List_Id := Empty_List;
179 R_Check_Off : Boolean := False);
180 -- Process a range expression that appears in a declaration context. The
181 -- range is analyzed and resolved with the base type of the given type,
182 -- and an appropriate check for expressions in non-static contexts made
183 -- on the bounds. R is analyzed and resolved using T, so the caller should
184 -- if necessary link R into the tree before the call, and in particular in
185 -- the case of a subtype declaration, it is appropriate to set the parent
186 -- pointer of R so that the types get properly frozen. The Check_List
187 -- parameter is used when the subprogram is called from
188 -- Build_Record_Init_Proc and is used to return a set of constraint
189 -- checking statements generated by the Checks package. R_Check_Off is
190 -- set to True when the call to Range_Check is to be skipped.
192 function Process_Subtype
193 (S : Node_Id;
194 Related_Nod : Node_Id;
195 Related_Id : Entity_Id := Empty;
196 Suffix : Character := ' ') return Entity_Id;
197 -- Process a subtype indication S and return corresponding entity.
198 -- Related_Nod is the node where the potential generated implicit types
199 -- will be inserted. The Related_Id and Suffix parameters are used to
200 -- build the associated Implicit type name.
202 procedure Process_Discriminants
203 (N : Node_Id;
204 Prev : Entity_Id := Empty);
205 -- Process the discriminants contained in an N_Full_Type_Declaration or
206 -- N_Incomplete_Type_Decl node N. If the declaration is a completion,
207 -- Prev is entity on the partial view, on which references are posted.
209 procedure Set_Completion_Referenced (E : Entity_Id);
210 -- If E is the completion of a private or incomplete type declaration,
211 -- or the completion of a deferred constant declaration, mark the entity
212 -- as referenced. Warnings on unused entities, if needed, go on the
213 -- partial view.
215 end Sem_Ch3;