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------------------------------------------------------------------------------
26
27with Nlists; use Nlists;
28with Types;  use Types;
29
30package 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);
42
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.
51
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.
60
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 ???)
64
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.
72
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.
77
78   procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id);
79   --  Process an access type declaration
80
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.
85
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.
90
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.
99
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.
112
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.
124
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.
129
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.
137
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.
144
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.
156
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.
163
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.
170
171   --    Full_T is the full view of the type whose full declaration is in N.
172   --
173   --    Priv_T is the private view of the type whose full declaration is in N.
174
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.
191
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.
201
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.
208
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.
214
215end Sem_Ch3;
216