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 with Atree; use Atree;
28 with Debug; use Debug;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Errout; use Errout;
32 with Exp_Ch7; use Exp_Ch7;
33 with Exp_Pakd; use Exp_Pakd;
34 with Exp_Util; use Exp_Util;
35 with Exp_Tss; use Exp_Tss;
36 with Layout; use Layout;
37 with Lib.Xref; use Lib.Xref;
38 with Nlists; use Nlists;
39 with Nmake; use Nmake;
41 with Restrict; use Restrict;
42 with Rident; use Rident;
44 with Sem_Cat; use Sem_Cat;
45 with Sem_Ch6; use Sem_Ch6;
46 with Sem_Ch7; use Sem_Ch7;
47 with Sem_Ch8; use Sem_Ch8;
48 with Sem_Ch13; use Sem_Ch13;
49 with Sem_Eval; use Sem_Eval;
50 with Sem_Mech; use Sem_Mech;
51 with Sem_Prag; use Sem_Prag;
52 with Sem_Res; use Sem_Res;
53 with Sem_Util; use Sem_Util;
54 with Sinfo; use Sinfo;
55 with Snames; use Snames;
56 with Stand; use Stand;
57 with Targparm; use Targparm;
58 with Tbuild; use Tbuild;
59 with Ttypes; use Ttypes;
60 with Uintp; use Uintp;
61 with Urealp; use Urealp;
63 package body Freeze is
65 -----------------------
66 -- Local Subprograms --
67 -----------------------
69 procedure Adjust_Esize_For_Alignment (Typ : Entity_Id);
70 -- Typ is a type that is being frozen. If no size clause is given,
71 -- but a default Esize has been computed, then this default Esize is
72 -- adjusted up if necessary to be consistent with a given alignment,
73 -- but never to a value greater than Long_Long_Integer'Size. This
74 -- is used for all discrete types and for fixed-point types.
76 procedure Build_And_Analyze_Renamed_Body
79 After : in out Node_Id);
80 -- Build body for a renaming declaration, insert in tree and analyze
82 procedure Check_Address_Clause (E : Entity_Id);
83 -- Apply legality checks to address clauses for object declarations,
84 -- at the point the object is frozen.
86 procedure Check_Strict_Alignment (E : Entity_Id);
87 -- E is a base type. If E is tagged or has a component that is aliased
88 -- or tagged or contains something this is aliased or tagged, set
91 procedure Check_Unsigned_Type (E : Entity_Id);
92 pragma Inline (Check_Unsigned_Type);
93 -- If E is a fixed-point or discrete type, then all the necessary work
94 -- to freeze it is completed except for possible setting of the flag
95 -- Is_Unsigned_Type, which is done by this procedure. The call has no
96 -- effect if the entity E is not a discrete or fixed-point type.
98 procedure Freeze_And_Append
101 Result : in out List_Id);
102 -- Freezes Ent using Freeze_Entity, and appends the resulting list of
103 -- nodes to Result, modifying Result from No_List if necessary.
105 procedure Freeze_Enumeration_Type (Typ : Entity_Id);
106 -- Freeze enumeration type. The Esize field is set as processing
107 -- proceeds (i.e. set by default when the type is declared and then
108 -- adjusted by rep clauses. What this procedure does is to make sure
109 -- that if a foreign convention is specified, and no specific size
110 -- is given, then the size must be at least Integer'Size.
112 procedure Freeze_Static_Object (E : Entity_Id);
113 -- If an object is frozen which has Is_Statically_Allocated set, then
114 -- all referenced types must also be marked with this flag. This routine
115 -- is in charge of meeting this requirement for the object entity E.
117 procedure Freeze_Subprogram (E : Entity_Id);
118 -- Perform freezing actions for a subprogram (create extra formals,
119 -- and set proper default mechanism values). Note that this routine
120 -- is not called for internal subprograms, for which neither of these
121 -- actions is needed (or desirable, we do not want for example to have
122 -- these extra formals present in initialization procedures, where they
123 -- would serve no purpose). In this call E is either a subprogram or
124 -- a subprogram type (i.e. an access to a subprogram).
126 function Is_Fully_Defined (T : Entity_Id) return Boolean;
127 -- True if T is not private and has no private components, or has a full
128 -- view. Used to determine whether the designated type of an access type
129 -- should be frozen when the access type is frozen. This is done when an
130 -- allocator is frozen, or an expression that may involve attributes of
131 -- the designated type. Otherwise freezing the access type does not freeze
132 -- the designated type.
134 procedure Process_Default_Expressions
136 After : in out Node_Id);
137 -- This procedure is called for each subprogram to complete processing
138 -- of default expressions at the point where all types are known to be
139 -- frozen. The expressions must be analyzed in full, to make sure that
140 -- all error processing is done (they have only been pre-analyzed). If
141 -- the expression is not an entity or literal, its analysis may generate
142 -- code which must not be executed. In that case we build a function
143 -- body to hold that code. This wrapper function serves no other purpose
144 -- (it used to be called to evaluate the default, but now the default is
145 -- inlined at each point of call).
147 procedure Set_Component_Alignment_If_Not_Set (Typ : Entity_Id);
148 -- Typ is a record or array type that is being frozen. This routine
149 -- sets the default component alignment from the scope stack values
150 -- if the alignment is otherwise not specified.
152 procedure Check_Debug_Info_Needed (T : Entity_Id);
153 -- As each entity is frozen, this routine is called to deal with the
154 -- setting of Debug_Info_Needed for the entity. This flag is set if
155 -- the entity comes from source, or if we are in Debug_Generated_Code
156 -- mode or if the -gnatdV debug flag is set. However, it never sets
157 -- the flag if Debug_Info_Off is set.
159 procedure Set_Debug_Info_Needed (T : Entity_Id);
160 -- Sets the Debug_Info_Needed flag on entity T if not already set, and
161 -- also on any entities that are needed by T (for an object, the type
162 -- of the object is needed, and for a type, the subsidiary types are
163 -- needed -- see body for details). Never has any effect on T if the
164 -- Debug_Info_Off flag is set.
166 procedure Undelay_Type (T : Entity_Id);
167 -- T is a type of a component that we know to be an Itype.
168 -- We don't want this to have a Freeze_Node, so ensure it doesn't.
169 -- Do the same for any Full_View or Corresponding_Record_Type.
171 procedure Warn_Overlay
175 -- Expr is the expression for an address clause for entity Nam whose type
176 -- is Typ. If Typ has a default initialization, and there is no explicit
177 -- initialization in the source declaration, check whether the address
178 -- clause might cause overlaying of an entity, and emit a warning on the
179 -- side effect that the initialization will cause.
181 -------------------------------
182 -- Adjust_Esize_For_Alignment --
183 -------------------------------
185 procedure Adjust_Esize_For_Alignment (Typ : Entity_Id) is
189 if Known_Esize (Typ) and then Known_Alignment (Typ) then
190 Align := Alignment_In_Bits (Typ);
192 if Align > Esize (Typ)
193 and then Align <= Standard_Long_Long_Integer_Size
195 Set_Esize (Typ, Align);
198 end Adjust_Esize_For_Alignment;
200 ------------------------------------
201 -- Build_And_Analyze_Renamed_Body --
202 ------------------------------------
204 procedure Build_And_Analyze_Renamed_Body
207 After : in out Node_Id)
209 Body_Node : constant Node_Id := Build_Renamed_Body (Decl, New_S);
211 Insert_After (After, Body_Node);
212 Mark_Rewrite_Insertion (Body_Node);
215 end Build_And_Analyze_Renamed_Body;
217 ------------------------
218 -- Build_Renamed_Body --
219 ------------------------
221 function Build_Renamed_Body
223 New_S : Entity_Id) return Node_Id
225 Loc : constant Source_Ptr := Sloc (New_S);
226 -- We use for the source location of the renamed body, the location
227 -- of the spec entity. It might seem more natural to use the location
228 -- of the renaming declaration itself, but that would be wrong, since
229 -- then the body we create would look as though it was created far
230 -- too late, and this could cause problems with elaboration order
231 -- analysis, particularly in connection with instantiations.
233 N : constant Node_Id := Unit_Declaration_Node (New_S);
234 Nam : constant Node_Id := Name (N);
236 Spec : constant Node_Id := New_Copy_Tree (Specification (Decl));
237 Actuals : List_Id := No_List;
242 O_Formal : Entity_Id;
243 Param_Spec : Node_Id;
246 -- Determine the entity being renamed, which is the target of the
247 -- call statement. If the name is an explicit dereference, this is
248 -- a renaming of a subprogram type rather than a subprogram. The
249 -- name itself is fully analyzed.
251 if Nkind (Nam) = N_Selected_Component then
252 Old_S := Entity (Selector_Name (Nam));
254 elsif Nkind (Nam) = N_Explicit_Dereference then
255 Old_S := Etype (Nam);
257 elsif Nkind (Nam) = N_Indexed_Component then
258 if Is_Entity_Name (Prefix (Nam)) then
259 Old_S := Entity (Prefix (Nam));
261 Old_S := Entity (Selector_Name (Prefix (Nam)));
264 elsif Nkind (Nam) = N_Character_Literal then
265 Old_S := Etype (New_S);
268 Old_S := Entity (Nam);
271 if Is_Entity_Name (Nam) then
273 -- If the renamed entity is a predefined operator, retain full
274 -- name to ensure its visibility.
276 if Ekind (Old_S) = E_Operator
277 and then Nkind (Nam) = N_Expanded_Name
279 Call_Name := New_Copy (Name (N));
281 Call_Name := New_Reference_To (Old_S, Loc);
285 Call_Name := New_Copy (Name (N));
287 -- The original name may have been overloaded, but
288 -- is fully resolved now.
290 Set_Is_Overloaded (Call_Name, False);
293 -- For simple renamings, subsequent calls can be expanded directly
294 -- as called to the renamed entity. The body must be generated in
295 -- any case for calls they may appear elsewhere.
297 if (Ekind (Old_S) = E_Function
298 or else Ekind (Old_S) = E_Procedure)
299 and then Nkind (Decl) = N_Subprogram_Declaration
301 Set_Body_To_Inline (Decl, Old_S);
304 -- The body generated for this renaming is an internal artifact, and
305 -- does not constitute a freeze point for the called entity.
307 Set_Must_Not_Freeze (Call_Name);
309 Formal := First_Formal (Defining_Entity (Decl));
311 if Present (Formal) then
314 while Present (Formal) loop
315 Append (New_Reference_To (Formal, Loc), Actuals);
316 Next_Formal (Formal);
320 -- If the renamed entity is an entry, inherit its profile. For
321 -- other renamings as bodies, both profiles must be subtype
322 -- conformant, so it is not necessary to replace the profile given
323 -- in the declaration. However, default values that are aggregates
324 -- are rewritten when partially analyzed, so we recover the original
325 -- aggregate to insure that subsequent conformity checking works.
326 -- Similarly, if the default expression was constant-folded, recover
327 -- the original expression.
329 Formal := First_Formal (Defining_Entity (Decl));
331 if Present (Formal) then
332 O_Formal := First_Formal (Old_S);
333 Param_Spec := First (Parameter_Specifications (Spec));
335 while Present (Formal) loop
336 if Is_Entry (Old_S) then
338 if Nkind (Parameter_Type (Param_Spec)) /=
341 Set_Etype (Formal, Etype (O_Formal));
342 Set_Entity (Parameter_Type (Param_Spec), Etype (O_Formal));
345 elsif Nkind (Default_Value (O_Formal)) = N_Aggregate
346 or else Nkind (Original_Node (Default_Value (O_Formal))) /=
347 Nkind (Default_Value (O_Formal))
349 Set_Expression (Param_Spec,
350 New_Copy_Tree (Original_Node (Default_Value (O_Formal))));
353 Next_Formal (Formal);
354 Next_Formal (O_Formal);
359 -- If the renamed entity is a function, the generated body contains a
360 -- return statement. Otherwise, build a procedure call. If the entity is
361 -- an entry, subsequent analysis of the call will transform it into the
362 -- proper entry or protected operation call. If the renamed entity is
363 -- a character literal, return it directly.
365 if Ekind (Old_S) = E_Function
366 or else Ekind (Old_S) = E_Operator
367 or else (Ekind (Old_S) = E_Subprogram_Type
368 and then Etype (Old_S) /= Standard_Void_Type)
371 Make_Return_Statement (Loc,
373 Make_Function_Call (Loc,
375 Parameter_Associations => Actuals));
377 elsif Ekind (Old_S) = E_Enumeration_Literal then
379 Make_Return_Statement (Loc,
380 Expression => New_Occurrence_Of (Old_S, Loc));
382 elsif Nkind (Nam) = N_Character_Literal then
384 Make_Return_Statement (Loc,
385 Expression => Call_Name);
389 Make_Procedure_Call_Statement (Loc,
391 Parameter_Associations => Actuals);
394 -- Create entities for subprogram body and formals
396 Set_Defining_Unit_Name (Spec,
397 Make_Defining_Identifier (Loc, Chars => Chars (New_S)));
399 Param_Spec := First (Parameter_Specifications (Spec));
401 while Present (Param_Spec) loop
402 Set_Defining_Identifier (Param_Spec,
403 Make_Defining_Identifier (Loc,
404 Chars => Chars (Defining_Identifier (Param_Spec))));
409 Make_Subprogram_Body (Loc,
410 Specification => Spec,
411 Declarations => New_List,
412 Handled_Statement_Sequence =>
413 Make_Handled_Sequence_Of_Statements (Loc,
414 Statements => New_List (Call_Node)));
416 if Nkind (Decl) /= N_Subprogram_Declaration then
418 Make_Subprogram_Declaration (Loc,
419 Specification => Specification (N)));
422 -- Link the body to the entity whose declaration it completes. If
423 -- the body is analyzed when the renamed entity is frozen, it may be
424 -- necessary to restore the proper scope (see package Exp_Ch13).
426 if Nkind (N) = N_Subprogram_Renaming_Declaration
427 and then Present (Corresponding_Spec (N))
429 Set_Corresponding_Spec (Body_Node, Corresponding_Spec (N));
431 Set_Corresponding_Spec (Body_Node, New_S);
435 end Build_Renamed_Body;
437 --------------------------
438 -- Check_Address_Clause --
439 --------------------------
441 procedure Check_Address_Clause (E : Entity_Id) is
442 Addr : constant Node_Id := Address_Clause (E);
444 Decl : constant Node_Id := Declaration_Node (E);
445 Typ : constant Entity_Id := Etype (E);
448 if Present (Addr) then
449 Expr := Expression (Addr);
451 -- If we have no initialization of any kind, then we don't
452 -- need to place any restrictions on the address clause, because
453 -- the object will be elaborated after the address clause is
454 -- evaluated. This happens if the declaration has no initial
455 -- expression, or the type has no implicit initialization, or
456 -- the object is imported.
458 -- The same holds for all initialized scalar types and all
459 -- access types. Packed bit arrays of size up to 64 are
460 -- represented using a modular type with an initialization
461 -- (to zero) and can be processed like other initialized
464 -- If the type is controlled, code to attach the object to a
465 -- finalization chain is generated at the point of declaration,
466 -- and therefore the elaboration of the object cannot be delayed:
467 -- the address expression must be a constant.
469 if (No (Expression (Decl))
470 and then not Controlled_Type (Typ)
472 (not Has_Non_Null_Base_Init_Proc (Typ)
473 or else Is_Imported (E)))
476 (Present (Expression (Decl))
477 and then Is_Scalar_Type (Typ))
483 (Is_Bit_Packed_Array (Typ)
485 Is_Modular_Integer_Type (Packed_Array_Type (Typ)))
489 -- Otherwise, we require the address clause to be constant
490 -- because the call to the initialization procedure (or the
491 -- attach code) has to happen at the point of the declaration.
494 Check_Constant_Address_Clause (Expr, E);
495 Set_Has_Delayed_Freeze (E, False);
498 if not Error_Posted (Expr)
499 and then not Controlled_Type (Typ)
501 Warn_Overlay (Expr, Typ, Name (Addr));
504 end Check_Address_Clause;
506 -----------------------------
507 -- Check_Compile_Time_Size --
508 -----------------------------
510 procedure Check_Compile_Time_Size (T : Entity_Id) is
512 procedure Set_Small_Size (T : Entity_Id; S : Uint);
513 -- Sets the compile time known size (32 bits or less) in the Esize
514 -- field, of T checking for a size clause that was given which attempts
515 -- to give a smaller size.
517 function Size_Known (T : Entity_Id) return Boolean;
518 -- Recursive function that does all the work
520 function Static_Discriminated_Components (T : Entity_Id) return Boolean;
521 -- If T is a constrained subtype, its size is not known if any of its
522 -- discriminant constraints is not static and it is not a null record.
523 -- The test is conservative and doesn't check that the components are
524 -- in fact constrained by non-static discriminant values. Could be made
531 procedure Set_Small_Size (T : Entity_Id; S : Uint) is
536 elsif Has_Size_Clause (T) then
537 if RM_Size (T) < S then
538 Error_Msg_Uint_1 := S;
540 ("size for & is too small, minimum is ^",
543 elsif Unknown_Esize (T) then
547 -- Set sizes if not set already
550 if Unknown_Esize (T) then
554 if Unknown_RM_Size (T) then
564 function Size_Known (T : Entity_Id) return Boolean is
572 if Size_Known_At_Compile_Time (T) then
575 elsif Is_Scalar_Type (T)
576 or else Is_Task_Type (T)
578 return not Is_Generic_Type (T);
580 elsif Is_Array_Type (T) then
581 if Ekind (T) = E_String_Literal_Subtype then
582 Set_Small_Size (T, Component_Size (T)
583 * String_Literal_Length (T));
586 elsif not Is_Constrained (T) then
589 -- Don't do any recursion on type with error posted, since
590 -- we may have a malformed type that leads us into a loop
592 elsif Error_Posted (T) then
595 elsif not Size_Known (Component_Type (T)) then
599 -- Check for all indexes static, and also compute possible
600 -- size (in case it is less than 32 and may be packable).
603 Esiz : Uint := Component_Size (T);
607 Index := First_Index (T);
608 while Present (Index) loop
609 if Nkind (Index) = N_Range then
610 Get_Index_Bounds (Index, Low, High);
612 elsif Error_Posted (Scalar_Range (Etype (Index))) then
616 Low := Type_Low_Bound (Etype (Index));
617 High := Type_High_Bound (Etype (Index));
620 if not Compile_Time_Known_Value (Low)
621 or else not Compile_Time_Known_Value (High)
622 or else Etype (Index) = Any_Type
627 Dim := Expr_Value (High) - Expr_Value (Low) + 1;
639 Set_Small_Size (T, Esiz);
643 elsif Is_Access_Type (T) then
646 elsif Is_Private_Type (T)
647 and then not Is_Generic_Type (T)
648 and then Present (Underlying_Type (T))
650 -- Don't do any recursion on type with error posted, since
651 -- we may have a malformed type that leads us into a loop
653 if Error_Posted (T) then
656 return Size_Known (Underlying_Type (T));
659 elsif Is_Record_Type (T) then
661 -- A class-wide type is never considered to have a known size
663 if Is_Class_Wide_Type (T) then
666 -- A subtype of a variant record must not have non-static
667 -- discriminanted components.
669 elsif T /= Base_Type (T)
670 and then not Static_Discriminated_Components (T)
674 -- Don't do any recursion on type with error posted, since
675 -- we may have a malformed type that leads us into a loop
677 elsif Error_Posted (T) then
681 -- Now look at the components of the record
684 -- The following two variables are used to keep track of
685 -- the size of packed records if we can tell the size of
686 -- the packed record in the front end. Packed_Size_Known
687 -- is True if so far we can figure out the size. It is
688 -- initialized to True for a packed record, unless the
689 -- record has discriminants. The reason we eliminate the
690 -- discriminated case is that we don't know the way the
691 -- back end lays out discriminated packed records. If
692 -- Packed_Size_Known is True, then Packed_Size is the
693 -- size in bits so far.
695 Packed_Size_Known : Boolean :=
697 and then not Has_Discriminants (T);
699 Packed_Size : Uint := Uint_0;
702 -- Test for variant part present
704 if Has_Discriminants (T)
705 and then Present (Parent (T))
706 and then Nkind (Parent (T)) = N_Full_Type_Declaration
707 and then Nkind (Type_Definition (Parent (T))) =
709 and then not Null_Present (Type_Definition (Parent (T)))
710 and then Present (Variant_Part
711 (Component_List (Type_Definition (Parent (T)))))
713 -- If variant part is present, and type is unconstrained,
714 -- then we must have defaulted discriminants, or a size
715 -- clause must be present for the type, or else the size
716 -- is definitely not known at compile time.
718 if not Is_Constrained (T)
720 No (Discriminant_Default_Value
721 (First_Discriminant (T)))
722 and then Unknown_Esize (T)
728 -- Loop through components
730 Comp := First_Entity (T);
731 while Present (Comp) loop
732 if Ekind (Comp) = E_Component
734 Ekind (Comp) = E_Discriminant
736 Ctyp := Etype (Comp);
738 -- We do not know the packed size if there is a
739 -- component clause present (we possibly could,
740 -- but this would only help in the case of a record
741 -- with partial rep clauses. That's because in the
742 -- case of full rep clauses, the size gets figured
743 -- out anyway by a different circuit).
745 if Present (Component_Clause (Comp)) then
746 Packed_Size_Known := False;
749 -- We need to identify a component that is an array
750 -- where the index type is an enumeration type with
751 -- non-standard representation, and some bound of the
752 -- type depends on a discriminant.
754 -- This is because gigi computes the size by doing a
755 -- substituation of the appropriate discriminant value
756 -- in the size expression for the base type, and gigi
757 -- is not clever enough to evaluate the resulting
758 -- expression (which involves a call to rep_to_pos)
761 -- It would be nice if gigi would either recognize that
762 -- this expression can be computed at compile time, or
763 -- alternatively figured out the size from the subtype
764 -- directly, where all the information is at hand ???
766 if Is_Array_Type (Etype (Comp))
767 and then Present (Packed_Array_Type (Etype (Comp)))
770 Ocomp : constant Entity_Id :=
771 Original_Record_Component (Comp);
772 OCtyp : constant Entity_Id := Etype (Ocomp);
778 Ind := First_Index (OCtyp);
779 while Present (Ind) loop
780 Indtyp := Etype (Ind);
782 if Is_Enumeration_Type (Indtyp)
783 and then Has_Non_Standard_Rep (Indtyp)
785 Lo := Type_Low_Bound (Indtyp);
786 Hi := Type_High_Bound (Indtyp);
788 if Is_Entity_Name (Lo)
790 Ekind (Entity (Lo)) = E_Discriminant
794 elsif Is_Entity_Name (Hi)
796 Ekind (Entity (Hi)) = E_Discriminant
807 -- Clearly size of record is not known if the size of
808 -- one of the components is not known.
810 if not Size_Known (Ctyp) then
814 -- Accumulate packed size if possible
816 if Packed_Size_Known then
818 -- We can only deal with elementary types, since for
819 -- non-elementary components, alignment enters into
820 -- the picture, and we don't know enough to handle
821 -- proper alignment in this context. Packed arrays
822 -- count as elementary if the representation is a
825 if Is_Elementary_Type (Ctyp)
826 or else (Is_Array_Type (Ctyp)
828 Present (Packed_Array_Type (Ctyp))
830 Is_Modular_Integer_Type
831 (Packed_Array_Type (Ctyp)))
833 -- If RM_Size is known and static, then we can
834 -- keep accumulating the packed size.
836 if Known_Static_RM_Size (Ctyp) then
838 -- A little glitch, to be removed sometime ???
839 -- gigi does not understand zero sizes yet.
841 if RM_Size (Ctyp) = Uint_0 then
842 Packed_Size_Known := False;
844 -- Normal case where we can keep accumulating
845 -- the packed array size.
848 Packed_Size := Packed_Size + RM_Size (Ctyp);
851 -- If we have a field whose RM_Size is not known
852 -- then we can't figure out the packed size here.
855 Packed_Size_Known := False;
858 -- If we have a non-elementary type we can't figure
859 -- out the packed array size (alignment issues).
862 Packed_Size_Known := False;
870 if Packed_Size_Known then
871 Set_Small_Size (T, Packed_Size);
882 -------------------------------------
883 -- Static_Discriminated_Components --
884 -------------------------------------
886 function Static_Discriminated_Components
887 (T : Entity_Id) return Boolean
889 Constraint : Elmt_Id;
892 if Has_Discriminants (T)
893 and then Present (Discriminant_Constraint (T))
894 and then Present (First_Component (T))
896 Constraint := First_Elmt (Discriminant_Constraint (T));
897 while Present (Constraint) loop
898 if not Compile_Time_Known_Value (Node (Constraint)) then
902 Next_Elmt (Constraint);
907 end Static_Discriminated_Components;
909 -- Start of processing for Check_Compile_Time_Size
912 Set_Size_Known_At_Compile_Time (T, Size_Known (T));
913 end Check_Compile_Time_Size;
915 -----------------------------
916 -- Check_Debug_Info_Needed --
917 -----------------------------
919 procedure Check_Debug_Info_Needed (T : Entity_Id) is
921 if Needs_Debug_Info (T) or else Debug_Info_Off (T) then
924 elsif Comes_From_Source (T)
925 or else Debug_Generated_Code
926 or else Debug_Flag_VV
928 Set_Debug_Info_Needed (T);
930 end Check_Debug_Info_Needed;
932 ----------------------------
933 -- Check_Strict_Alignment --
934 ----------------------------
936 procedure Check_Strict_Alignment (E : Entity_Id) is
940 if Is_Tagged_Type (E) or else Is_Concurrent_Type (E) then
941 Set_Strict_Alignment (E);
943 elsif Is_Array_Type (E) then
944 Set_Strict_Alignment (E, Strict_Alignment (Component_Type (E)));
946 elsif Is_Record_Type (E) then
947 if Is_Limited_Record (E) then
948 Set_Strict_Alignment (E);
952 Comp := First_Component (E);
954 while Present (Comp) loop
955 if not Is_Type (Comp)
956 and then (Strict_Alignment (Etype (Comp))
957 or else Is_Aliased (Comp))
959 Set_Strict_Alignment (E);
963 Next_Component (Comp);
966 end Check_Strict_Alignment;
968 -------------------------
969 -- Check_Unsigned_Type --
970 -------------------------
972 procedure Check_Unsigned_Type (E : Entity_Id) is
973 Ancestor : Entity_Id;
978 if not Is_Discrete_Or_Fixed_Point_Type (E) then
982 -- Do not attempt to analyze case where range was in error
984 if Error_Posted (Scalar_Range (E)) then
988 -- The situation that is non trivial is something like
990 -- subtype x1 is integer range -10 .. +10;
991 -- subtype x2 is x1 range 0 .. V1;
992 -- subtype x3 is x2 range V2 .. V3;
993 -- subtype x4 is x3 range V4 .. V5;
995 -- where Vn are variables. Here the base type is signed, but we still
996 -- know that x4 is unsigned because of the lower bound of x2.
998 -- The only way to deal with this is to look up the ancestor chain
1002 if Ancestor = Any_Type or else Etype (Ancestor) = Any_Type then
1006 Lo_Bound := Type_Low_Bound (Ancestor);
1008 if Compile_Time_Known_Value (Lo_Bound) then
1010 if Expr_Rep_Value (Lo_Bound) >= 0 then
1011 Set_Is_Unsigned_Type (E, True);
1017 Ancestor := Ancestor_Subtype (Ancestor);
1019 -- If no ancestor had a static lower bound, go to base type
1021 if No (Ancestor) then
1023 -- Note: the reason we still check for a compile time known
1024 -- value for the base type is that at least in the case of
1025 -- generic formals, we can have bounds that fail this test,
1026 -- and there may be other cases in error situations.
1028 Btyp := Base_Type (E);
1030 if Btyp = Any_Type or else Etype (Btyp) = Any_Type then
1034 Lo_Bound := Type_Low_Bound (Base_Type (E));
1036 if Compile_Time_Known_Value (Lo_Bound)
1037 and then Expr_Rep_Value (Lo_Bound) >= 0
1039 Set_Is_Unsigned_Type (E, True);
1046 end Check_Unsigned_Type;
1048 -----------------------------
1049 -- Expand_Atomic_Aggregate --
1050 -----------------------------
1052 procedure Expand_Atomic_Aggregate (E : Entity_Id; Typ : Entity_Id) is
1053 Loc : constant Source_Ptr := Sloc (E);
1058 if (Nkind (Parent (E)) = N_Object_Declaration
1059 or else Nkind (Parent (E)) = N_Assignment_Statement)
1060 and then Comes_From_Source (Parent (E))
1061 and then Nkind (E) = N_Aggregate
1064 Make_Defining_Identifier (Loc,
1065 New_Internal_Name ('T'));
1068 Make_Object_Declaration (Loc,
1069 Defining_Identifier => Temp,
1070 Object_definition => New_Occurrence_Of (Typ, Loc),
1071 Expression => Relocate_Node (E));
1072 Insert_Before (Parent (E), New_N);
1075 Set_Expression (Parent (E), New_Occurrence_Of (Temp, Loc));
1077 -- To prevent the temporary from being constant-folded (which
1078 -- would lead to the same piecemeal assignment on the original
1079 -- target) indicate to the back-end that the temporary is a
1080 -- variable with real storage. See description of this flag
1081 -- in Einfo, and the notes on N_Assignment_Statement and
1082 -- N_Object_Declaration in Sinfo.
1084 Set_Is_True_Constant (Temp, False);
1086 end Expand_Atomic_Aggregate;
1092 -- Note: the easy coding for this procedure would be to just build a
1093 -- single list of freeze nodes and then insert them and analyze them
1094 -- all at once. This won't work, because the analysis of earlier freeze
1095 -- nodes may recursively freeze types which would otherwise appear later
1096 -- on in the freeze list. So we must analyze and expand the freeze nodes
1097 -- as they are generated.
1099 procedure Freeze_All (From : Entity_Id; After : in out Node_Id) is
1100 Loc : constant Source_Ptr := Sloc (After);
1104 procedure Freeze_All_Ent (From : Entity_Id; After : in out Node_Id);
1105 -- This is the internal recursive routine that does freezing of
1106 -- entities (but NOT the analysis of default expressions, which
1107 -- should not be recursive, we don't want to analyze those till
1108 -- we are sure that ALL the types are frozen).
1110 --------------------
1111 -- Freeze_All_Ent --
1112 --------------------
1114 procedure Freeze_All_Ent
1116 After : in out Node_Id)
1122 procedure Process_Flist;
1123 -- If freeze nodes are present, insert and analyze, and reset
1124 -- cursor for next insertion.
1130 procedure Process_Flist is
1132 if Is_Non_Empty_List (Flist) then
1133 Lastn := Next (After);
1134 Insert_List_After_And_Analyze (After, Flist);
1136 if Present (Lastn) then
1137 After := Prev (Lastn);
1139 After := Last (List_Containing (After));
1144 -- Start or processing for Freeze_All_Ent
1148 while Present (E) loop
1150 -- If the entity is an inner package which is not a package
1151 -- renaming, then its entities must be frozen at this point.
1152 -- Note that such entities do NOT get frozen at the end of
1153 -- the nested package itself (only library packages freeze).
1155 -- Same is true for task declarations, where anonymous records
1156 -- created for entry parameters must be frozen.
1158 if Ekind (E) = E_Package
1159 and then No (Renamed_Object (E))
1160 and then not Is_Child_Unit (E)
1161 and then not Is_Frozen (E)
1164 Install_Visible_Declarations (E);
1165 Install_Private_Declarations (E);
1167 Freeze_All (First_Entity (E), After);
1169 End_Package_Scope (E);
1171 elsif Ekind (E) in Task_Kind
1173 (Nkind (Parent (E)) = N_Task_Type_Declaration
1175 Nkind (Parent (E)) = N_Single_Task_Declaration)
1178 Freeze_All (First_Entity (E), After);
1181 -- For a derived tagged type, we must ensure that all the
1182 -- primitive operations of the parent have been frozen, so
1183 -- that their addresses will be in the parent's dispatch table
1184 -- at the point it is inherited.
1186 elsif Ekind (E) = E_Record_Type
1187 and then Is_Tagged_Type (E)
1188 and then Is_Tagged_Type (Etype (E))
1189 and then Is_Derived_Type (E)
1192 Prim_List : constant Elist_Id :=
1193 Primitive_Operations (Etype (E));
1199 Prim := First_Elmt (Prim_List);
1201 while Present (Prim) loop
1202 Subp := Node (Prim);
1204 if Comes_From_Source (Subp)
1205 and then not Is_Frozen (Subp)
1207 Flist := Freeze_Entity (Subp, Loc);
1216 if not Is_Frozen (E) then
1217 Flist := Freeze_Entity (E, Loc);
1221 -- If an incomplete type is still not frozen, this may be
1222 -- a premature freezing because of a body declaration that
1223 -- follows. Indicate where the freezing took place.
1225 -- If the freezing is caused by the end of the current
1226 -- declarative part, it is a Taft Amendment type, and there
1229 if not Is_Frozen (E)
1230 and then Ekind (E) = E_Incomplete_Type
1233 Bod : constant Node_Id := Next (After);
1236 if (Nkind (Bod) = N_Subprogram_Body
1237 or else Nkind (Bod) = N_Entry_Body
1238 or else Nkind (Bod) = N_Package_Body
1239 or else Nkind (Bod) = N_Protected_Body
1240 or else Nkind (Bod) = N_Task_Body
1241 or else Nkind (Bod) in N_Body_Stub)
1243 List_Containing (After) = List_Containing (Parent (E))
1245 Error_Msg_Sloc := Sloc (Next (After));
1247 ("type& is frozen# before its full declaration",
1257 -- Start of processing for Freeze_All
1260 Freeze_All_Ent (From, After);
1262 -- Now that all types are frozen, we can deal with default expressions
1263 -- that require us to build a default expression functions. This is the
1264 -- point at which such functions are constructed (after all types that
1265 -- might be used in such expressions have been frozen).
1267 -- We also add finalization chains to access types whose designated
1268 -- types are controlled. This is normally done when freezing the type,
1269 -- but this misses recursive type definitions where the later members
1270 -- of the recursion introduce controlled components (e.g. 5624-001).
1272 -- Loop through entities
1275 while Present (E) loop
1276 if Is_Subprogram (E) then
1278 if not Default_Expressions_Processed (E) then
1279 Process_Default_Expressions (E, After);
1282 if not Has_Completion (E) then
1283 Decl := Unit_Declaration_Node (E);
1285 if Nkind (Decl) = N_Subprogram_Renaming_Declaration then
1286 Build_And_Analyze_Renamed_Body (Decl, E, After);
1288 elsif Nkind (Decl) = N_Subprogram_Declaration
1289 and then Present (Corresponding_Body (Decl))
1291 Nkind (Unit_Declaration_Node (Corresponding_Body (Decl)))
1292 = N_Subprogram_Renaming_Declaration
1294 Build_And_Analyze_Renamed_Body
1295 (Decl, Corresponding_Body (Decl), After);
1299 elsif Ekind (E) in Task_Kind
1301 (Nkind (Parent (E)) = N_Task_Type_Declaration
1303 Nkind (Parent (E)) = N_Single_Task_Declaration)
1308 Ent := First_Entity (E);
1310 while Present (Ent) loop
1313 and then not Default_Expressions_Processed (Ent)
1315 Process_Default_Expressions (Ent, After);
1322 elsif Is_Access_Type (E)
1323 and then Comes_From_Source (E)
1324 and then Ekind (Directly_Designated_Type (E)) = E_Incomplete_Type
1325 and then Controlled_Type (Designated_Type (E))
1326 and then No (Associated_Final_Chain (E))
1328 Build_Final_List (Parent (E), E);
1335 -----------------------
1336 -- Freeze_And_Append --
1337 -----------------------
1339 procedure Freeze_And_Append
1342 Result : in out List_Id)
1344 L : constant List_Id := Freeze_Entity (Ent, Loc);
1346 if Is_Non_Empty_List (L) then
1347 if Result = No_List then
1350 Append_List (L, Result);
1353 end Freeze_And_Append;
1359 procedure Freeze_Before (N : Node_Id; T : Entity_Id) is
1360 Freeze_Nodes : constant List_Id := Freeze_Entity (T, Sloc (N));
1362 if Is_Non_Empty_List (Freeze_Nodes) then
1363 Insert_Actions (N, Freeze_Nodes);
1371 function Freeze_Entity (E : Entity_Id; Loc : Source_Ptr) return List_Id is
1372 Test_E : Entity_Id := E;
1380 procedure Check_Current_Instance (Comp_Decl : Node_Id);
1381 -- Check that an Access or Unchecked_Access attribute with a prefix
1382 -- which is the current instance type can only be applied when the type
1385 function After_Last_Declaration return Boolean;
1386 -- If Loc is a freeze_entity that appears after the last declaration
1387 -- in the scope, inhibit error messages on late completion.
1389 procedure Freeze_Record_Type (Rec : Entity_Id);
1390 -- Freeze each component, handle some representation clauses, and freeze
1391 -- primitive operations if this is a tagged type.
1393 ----------------------------
1394 -- After_Last_Declaration --
1395 ----------------------------
1397 function After_Last_Declaration return Boolean is
1398 Spec : constant Node_Id := Parent (Current_Scope);
1401 if Nkind (Spec) = N_Package_Specification then
1402 if Present (Private_Declarations (Spec)) then
1403 return Loc >= Sloc (Last (Private_Declarations (Spec)));
1405 elsif Present (Visible_Declarations (Spec)) then
1406 return Loc >= Sloc (Last (Visible_Declarations (Spec)));
1414 end After_Last_Declaration;
1416 ----------------------------
1417 -- Check_Current_Instance --
1418 ----------------------------
1420 procedure Check_Current_Instance (Comp_Decl : Node_Id) is
1422 function Process (N : Node_Id) return Traverse_Result;
1423 -- Process routine to apply check to given node
1429 function Process (N : Node_Id) return Traverse_Result is
1432 when N_Attribute_Reference =>
1433 if (Attribute_Name (N) = Name_Access
1435 Attribute_Name (N) = Name_Unchecked_Access)
1436 and then Is_Entity_Name (Prefix (N))
1437 and then Is_Type (Entity (Prefix (N)))
1438 and then Entity (Prefix (N)) = E
1441 ("current instance must be a limited type", Prefix (N));
1447 when others => return OK;
1451 procedure Traverse is new Traverse_Proc (Process);
1453 -- Start of processing for Check_Current_Instance
1456 Traverse (Comp_Decl);
1457 end Check_Current_Instance;
1459 ------------------------
1460 -- Freeze_Record_Type --
1461 ------------------------
1463 procedure Freeze_Record_Type (Rec : Entity_Id) is
1470 Unplaced_Component : Boolean := False;
1471 -- Set True if we find at least one component with no component
1472 -- clause (used to warn about useless Pack pragmas).
1474 Placed_Component : Boolean := False;
1475 -- Set True if we find at least one component with a component
1476 -- clause (used to warn about useless Bit_Order pragmas).
1478 procedure Check_Itype (Desig : Entity_Id);
1479 -- If the component subtype is an access to a constrained subtype
1480 -- of an already frozen type, make the subtype frozen as well. It
1481 -- might otherwise be frozen in the wrong scope, and a freeze node
1482 -- on subtype has no effect.
1488 procedure Check_Itype (Desig : Entity_Id) is
1490 if not Is_Frozen (Desig)
1491 and then Is_Frozen (Base_Type (Desig))
1493 Set_Is_Frozen (Desig);
1495 -- In addition, add an Itype_Reference to ensure that the
1496 -- access subtype is elaborated early enough. This cannot
1497 -- be done if the subtype may depend on discriminants.
1499 if Ekind (Comp) = E_Component
1500 and then Is_Itype (Etype (Comp))
1501 and then not Has_Discriminants (Rec)
1503 IR := Make_Itype_Reference (Sloc (Comp));
1504 Set_Itype (IR, Desig);
1507 Result := New_List (IR);
1509 Append (IR, Result);
1515 -- Start of processing for Freeze_Record_Type
1518 -- If this is a subtype of a controlled type, declared without
1519 -- a constraint, the _controller may not appear in the component
1520 -- list if the parent was not frozen at the point of subtype
1521 -- declaration. Inherit the _controller component now.
1523 if Rec /= Base_Type (Rec)
1524 and then Has_Controlled_Component (Rec)
1526 if Nkind (Parent (Rec)) = N_Subtype_Declaration
1527 and then Is_Entity_Name (Subtype_Indication (Parent (Rec)))
1529 Set_First_Entity (Rec, First_Entity (Base_Type (Rec)));
1531 -- If this is an internal type without a declaration, as for
1532 -- record component, the base type may not yet be frozen, and its
1533 -- controller has not been created. Add an explicit freeze node
1534 -- for the itype, so it will be frozen after the base type. This
1535 -- freeze node is used to communicate with the expander, in order
1536 -- to create the controller for the enclosing record, and it is
1537 -- deleted afterwards (see exp_ch3). It must not be created when
1538 -- expansion is off, because it might appear in the wrong context
1539 -- for the back end.
1541 elsif Is_Itype (Rec)
1542 and then Has_Delayed_Freeze (Base_Type (Rec))
1544 Nkind (Associated_Node_For_Itype (Rec)) =
1545 N_Component_Declaration
1546 and then Expander_Active
1548 Ensure_Freeze_Node (Rec);
1552 -- Freeze components and embedded subtypes
1554 Comp := First_Entity (Rec);
1556 while Present (Comp) loop
1558 -- First handle the (real) component case
1560 if Ekind (Comp) = E_Component
1561 or else Ekind (Comp) = E_Discriminant
1564 CC : constant Node_Id := Component_Clause (Comp);
1567 -- Freezing a record type freezes the type of each of its
1568 -- components. However, if the type of the component is
1569 -- part of this record, we do not want or need a separate
1570 -- Freeze_Node. Note that Is_Itype is wrong because that's
1571 -- also set in private type cases. We also can't check for
1572 -- the Scope being exactly Rec because of private types and
1573 -- record extensions.
1575 if Is_Itype (Etype (Comp))
1576 and then Is_Record_Type (Underlying_Type
1577 (Scope (Etype (Comp))))
1579 Undelay_Type (Etype (Comp));
1582 Freeze_And_Append (Etype (Comp), Loc, Result);
1584 -- Check for error of component clause given for variable
1585 -- sized type. We have to delay this test till this point,
1586 -- since the component type has to be frozen for us to know
1587 -- if it is variable length. We omit this test in a generic
1588 -- context, it will be applied at instantiation time.
1590 if Present (CC) then
1591 Placed_Component := True;
1593 if Inside_A_Generic then
1596 elsif not Size_Known_At_Compile_Time
1597 (Underlying_Type (Etype (Comp)))
1600 ("component clause not allowed for variable " &
1601 "length component", CC);
1605 Unplaced_Component := True;
1608 -- Case of component requires byte alignment
1610 if Must_Be_On_Byte_Boundary (Etype (Comp)) then
1612 -- Set the enclosing record to also require byte align
1614 Set_Must_Be_On_Byte_Boundary (Rec);
1616 -- Check for component clause that is inconsistent
1617 -- with the required byte boundary alignment.
1620 and then Normalized_First_Bit (Comp) mod
1621 System_Storage_Unit /= 0
1624 ("component & must be byte aligned",
1625 Component_Name (Component_Clause (Comp)));
1629 -- If component clause is present, then deal with the
1630 -- non-default bit order case. We cannot do this before
1631 -- the freeze point, because there is no required order
1632 -- for the component clause and the bit_order clause.
1634 -- We only do this processing for the base type, and in
1635 -- fact that's important, since otherwise if there are
1636 -- record subtypes, we could reverse the bits once for
1637 -- each subtype, which would be incorrect.
1640 and then Reverse_Bit_Order (Rec)
1641 and then Ekind (E) = E_Record_Type
1644 CFB : constant Uint := Component_Bit_Offset (Comp);
1645 CSZ : constant Uint := Esize (Comp);
1646 CLC : constant Node_Id := Component_Clause (Comp);
1647 Pos : constant Node_Id := Position (CLC);
1648 FB : constant Node_Id := First_Bit (CLC);
1650 Storage_Unit_Offset : constant Uint :=
1651 CFB / System_Storage_Unit;
1653 Start_Bit : constant Uint :=
1654 CFB mod System_Storage_Unit;
1657 -- Cases where field goes over storage unit boundary
1659 if Start_Bit + CSZ > System_Storage_Unit then
1661 -- Allow multi-byte field but generate warning
1663 if Start_Bit mod System_Storage_Unit = 0
1664 and then CSZ mod System_Storage_Unit = 0
1667 ("multi-byte field specified with non-standard"
1668 & " Bit_Order?", CLC);
1670 if Bytes_Big_Endian then
1672 ("bytes are not reversed "
1673 & "(component is big-endian)?", CLC);
1676 ("bytes are not reversed "
1677 & "(component is little-endian)?", CLC);
1680 -- Do not allow non-contiguous field
1684 ("attempt to specify non-contiguous field"
1685 & " not permitted", CLC);
1687 ("\(caused by non-standard Bit_Order "
1688 & "specified)", CLC);
1691 -- Case where field fits in one storage unit
1694 -- Give warning if suspicious component clause
1696 if Intval (FB) >= System_Storage_Unit then
1698 ("?Bit_Order clause does not affect " &
1699 "byte ordering", Pos);
1701 Intval (Pos) + Intval (FB) /
1702 System_Storage_Unit;
1704 ("?position normalized to ^ before bit " &
1705 "order interpreted", Pos);
1708 -- Here is where we fix up the Component_Bit_Offset
1709 -- value to account for the reverse bit order.
1710 -- Some examples of what needs to be done are:
1712 -- First_Bit .. Last_Bit Component_Bit_Offset
1715 -- 0 .. 0 7 .. 7 0 7
1716 -- 0 .. 1 6 .. 7 0 6
1717 -- 0 .. 2 5 .. 7 0 5
1718 -- 0 .. 7 0 .. 7 0 4
1720 -- 1 .. 1 6 .. 6 1 6
1721 -- 1 .. 4 3 .. 6 1 3
1722 -- 4 .. 7 0 .. 3 4 0
1724 -- The general rule is that the first bit is
1725 -- is obtained by subtracting the old ending bit
1726 -- from storage_unit - 1.
1728 Set_Component_Bit_Offset
1730 (Storage_Unit_Offset * System_Storage_Unit) +
1731 (System_Storage_Unit - 1) -
1732 (Start_Bit + CSZ - 1));
1734 Set_Normalized_First_Bit
1736 Component_Bit_Offset (Comp) mod
1737 System_Storage_Unit);
1744 -- If the component is an Itype with Delayed_Freeze and is either
1745 -- a record or array subtype and its base type has not yet been
1746 -- frozen, we must remove this from the entity list of this
1747 -- record and put it on the entity list of the scope of its base
1748 -- type. Note that we know that this is not the type of a
1749 -- component since we cleared Has_Delayed_Freeze for it in the
1750 -- previous loop. Thus this must be the Designated_Type of an
1751 -- access type, which is the type of a component.
1754 and then Is_Type (Scope (Comp))
1755 and then Is_Composite_Type (Comp)
1756 and then Base_Type (Comp) /= Comp
1757 and then Has_Delayed_Freeze (Comp)
1758 and then not Is_Frozen (Base_Type (Comp))
1761 Will_Be_Frozen : Boolean := False;
1762 S : Entity_Id := Scope (Rec);
1765 -- We have a pretty bad kludge here. Suppose Rec is a
1766 -- subtype being defined in a subprogram that's created
1767 -- as part of the freezing of Rec'Base. In that case,
1768 -- we know that Comp'Base must have already been frozen by
1769 -- the time we get to elaborate this because Gigi doesn't
1770 -- elaborate any bodies until it has elaborated all of the
1771 -- declarative part. But Is_Frozen will not be set at this
1772 -- point because we are processing code in lexical order.
1774 -- We detect this case by going up the Scope chain of
1775 -- Rec and seeing if we have a subprogram scope before
1776 -- reaching the top of the scope chain or that of Comp'Base.
1777 -- If we do, then mark that Comp'Base will actually be
1778 -- frozen. If so, we merely undelay it.
1780 while Present (S) loop
1781 if Is_Subprogram (S) then
1782 Will_Be_Frozen := True;
1784 elsif S = Scope (Base_Type (Comp)) then
1791 if Will_Be_Frozen then
1792 Undelay_Type (Comp);
1794 if Present (Prev) then
1795 Set_Next_Entity (Prev, Next_Entity (Comp));
1797 Set_First_Entity (Rec, Next_Entity (Comp));
1800 -- Insert in entity list of scope of base type (which
1801 -- must be an enclosing scope, because still unfrozen).
1803 Append_Entity (Comp, Scope (Base_Type (Comp)));
1807 -- If the component is an access type with an allocator as
1808 -- default value, the designated type will be frozen by the
1809 -- corresponding expression in init_proc. In order to place the
1810 -- freeze node for the designated type before that for the
1811 -- current record type, freeze it now.
1813 -- Same process if the component is an array of access types,
1814 -- initialized with an aggregate. If the designated type is
1815 -- private, it cannot contain allocators, and it is premature to
1816 -- freeze the type, so we check for this as well.
1818 elsif Is_Access_Type (Etype (Comp))
1819 and then Present (Parent (Comp))
1820 and then Present (Expression (Parent (Comp)))
1821 and then Nkind (Expression (Parent (Comp))) = N_Allocator
1824 Alloc : constant Node_Id := Expression (Parent (Comp));
1827 -- If component is pointer to a classwide type, freeze
1828 -- the specific type in the expression being allocated.
1829 -- The expression may be a subtype indication, in which
1830 -- case freeze the subtype mark.
1832 if Is_Class_Wide_Type (Designated_Type (Etype (Comp))) then
1833 if Is_Entity_Name (Expression (Alloc)) then
1835 (Entity (Expression (Alloc)), Loc, Result);
1837 Nkind (Expression (Alloc)) = N_Subtype_Indication
1840 (Entity (Subtype_Mark (Expression (Alloc))),
1844 elsif Is_Itype (Designated_Type (Etype (Comp))) then
1845 Check_Itype (Designated_Type (Etype (Comp)));
1849 (Designated_Type (Etype (Comp)), Loc, Result);
1853 elsif Is_Access_Type (Etype (Comp))
1854 and then Is_Itype (Designated_Type (Etype (Comp)))
1856 Check_Itype (Designated_Type (Etype (Comp)));
1858 elsif Is_Array_Type (Etype (Comp))
1859 and then Is_Access_Type (Component_Type (Etype (Comp)))
1860 and then Present (Parent (Comp))
1861 and then Nkind (Parent (Comp)) = N_Component_Declaration
1862 and then Present (Expression (Parent (Comp)))
1863 and then Nkind (Expression (Parent (Comp))) = N_Aggregate
1864 and then Is_Fully_Defined
1865 (Designated_Type (Component_Type (Etype (Comp))))
1869 (Component_Type (Etype (Comp))), Loc, Result);
1876 -- Check for useless pragma Bit_Order
1878 if not Placed_Component and then Reverse_Bit_Order (Rec) then
1879 ADC := Get_Attribute_Definition_Clause (Rec, Attribute_Bit_Order);
1880 Error_Msg_N ("?Bit_Order specification has no effect", ADC);
1881 Error_Msg_N ("\?since no component clauses were specified", ADC);
1884 -- Check for useless pragma Pack when all components placed. We only
1885 -- do this check for record types, not subtypes, since a subtype may
1886 -- have all its components placed, and it still makes perfectly good
1887 -- sense to pack other subtypes or the parent type.
1889 if Ekind (Rec) = E_Record_Type
1890 and then Is_Packed (Rec)
1891 and then not Unplaced_Component
1893 -- Reset packed status. Probably not necessary, but we do it
1894 -- so that there is no chance of the back end doing something
1895 -- strange with this redundant indication of packing.
1897 Set_Is_Packed (Rec, False);
1899 -- Give warning if redundant constructs warnings on
1901 if Warn_On_Redundant_Constructs then
1903 ("?pragma Pack has no effect, no unplaced components",
1904 Get_Rep_Pragma (Rec, Name_Pack));
1908 -- If this is the record corresponding to a remote type, freeze the
1909 -- remote type here since that is what we are semantically freezing.
1910 -- This prevents the freeze node for that type in an inner scope.
1912 -- Also, Check for controlled components and unchecked unions.
1913 -- Finally, enforce the restriction that access attributes with a
1914 -- current instance prefix can only apply to limited types.
1916 if Ekind (Rec) = E_Record_Type then
1917 if Present (Corresponding_Remote_Type (Rec)) then
1919 (Corresponding_Remote_Type (Rec), Loc, Result);
1922 Comp := First_Component (Rec);
1923 while Present (Comp) loop
1924 if Has_Controlled_Component (Etype (Comp))
1925 or else (Chars (Comp) /= Name_uParent
1926 and then Is_Controlled (Etype (Comp)))
1927 or else (Is_Protected_Type (Etype (Comp))
1929 (Corresponding_Record_Type (Etype (Comp)))
1930 and then Has_Controlled_Component
1931 (Corresponding_Record_Type (Etype (Comp))))
1933 Set_Has_Controlled_Component (Rec);
1937 if Has_Unchecked_Union (Etype (Comp)) then
1938 Set_Has_Unchecked_Union (Rec);
1941 if Has_Per_Object_Constraint (Comp)
1942 and then not Is_Limited_Type (Rec)
1944 -- Scan component declaration for likely misuses of current
1945 -- instance, either in a constraint or a default expression.
1947 Check_Current_Instance (Parent (Comp));
1950 Next_Component (Comp);
1954 Set_Component_Alignment_If_Not_Set (Rec);
1956 -- For first subtypes, check if there are any fixed-point fields with
1957 -- component clauses, where we must check the size. This is not done
1958 -- till the freeze point, since for fixed-point types, we do not know
1959 -- the size until the type is frozen. Similar processing applies to
1960 -- bit packed arrays.
1962 if Is_First_Subtype (Rec) then
1963 Comp := First_Component (Rec);
1965 while Present (Comp) loop
1966 if Present (Component_Clause (Comp))
1967 and then (Is_Fixed_Point_Type (Etype (Comp))
1969 Is_Bit_Packed_Array (Etype (Comp)))
1972 (Component_Name (Component_Clause (Comp)),
1978 Next_Component (Comp);
1981 end Freeze_Record_Type;
1983 -- Start of processing for Freeze_Entity
1986 -- We are going to test for various reasons why this entity need not be
1987 -- frozen here, but in the case of an Itype that's defined within a
1988 -- record, that test actually applies to the record.
1990 if Is_Itype (E) and then Is_Record_Type (Scope (E)) then
1991 Test_E := Scope (E);
1992 elsif Is_Itype (E) and then Present (Underlying_Type (Scope (E)))
1993 and then Is_Record_Type (Underlying_Type (Scope (E)))
1995 Test_E := Underlying_Type (Scope (E));
1998 -- Do not freeze if already frozen since we only need one freeze node
2000 if Is_Frozen (E) then
2003 -- It is improper to freeze an external entity within a generic because
2004 -- its freeze node will appear in a non-valid context. The entity will
2005 -- be frozen in the proper scope after the current generic is analyzed.
2007 elsif Inside_A_Generic and then External_Ref_In_Generic (Test_E) then
2010 -- Do not freeze a global entity within an inner scope created during
2011 -- expansion. A call to subprogram E within some internal procedure
2012 -- (a stream attribute for example) might require freezing E, but the
2013 -- freeze node must appear in the same declarative part as E itself.
2014 -- The two-pass elaboration mechanism in gigi guarantees that E will
2015 -- be frozen before the inner call is elaborated. We exclude constants
2016 -- from this test, because deferred constants may be frozen early, and
2017 -- must be diagnosed (see e.g. 1522-005). If the enclosing subprogram
2018 -- comes from source, or is a generic instance, then the freeze point
2019 -- is the one mandated by the language. and we freze the entity.
2021 elsif In_Open_Scopes (Scope (Test_E))
2022 and then Scope (Test_E) /= Current_Scope
2023 and then Ekind (Test_E) /= E_Constant
2026 S : Entity_Id := Current_Scope;
2029 while Present (S) loop
2030 if Is_Overloadable (S) then
2031 if Comes_From_Source (S)
2032 or else Is_Generic_Instance (S)
2044 -- Similarly, an inlined instance body may make reference to global
2045 -- entities, but these references cannot be the proper freezing point
2046 -- for them, and the the absence of inlining freezing will take place
2047 -- in their own scope. Normally instance bodies are analyzed after
2048 -- the enclosing compilation, and everything has been frozen at the
2049 -- proper place, but with front-end inlining an instance body is
2050 -- compiled before the end of the enclosing scope, and as a result
2051 -- out-of-order freezing must be prevented.
2053 elsif Front_End_Inlining
2054 and then In_Instance_Body
2055 and then Present (Scope (Test_E))
2058 S : Entity_Id := Scope (Test_E);
2061 while Present (S) loop
2062 if Is_Generic_Instance (S) then
2075 -- Here to freeze the entity
2080 -- Case of entity being frozen is other than a type
2082 if not Is_Type (E) then
2084 -- If entity is exported or imported and does not have an external
2085 -- name, now is the time to provide the appropriate default name.
2086 -- Skip this if the entity is stubbed, since we don't need a name
2087 -- for any stubbed routine.
2089 if (Is_Imported (E) or else Is_Exported (E))
2090 and then No (Interface_Name (E))
2091 and then Convention (E) /= Convention_Stubbed
2093 Set_Encoded_Interface_Name
2094 (E, Get_Default_External_Name (E));
2096 -- Special processing for atomic objects appearing in object decls
2099 and then Nkind (Parent (E)) = N_Object_Declaration
2100 and then Present (Expression (Parent (E)))
2103 Expr : constant Node_Id := Expression (Parent (E));
2106 -- If expression is an aggregate, assign to a temporary to
2107 -- ensure that the actual assignment is done atomically rather
2108 -- than component-wise (the assignment to the temp may be done
2109 -- component-wise, but that is harmless.
2111 if Nkind (Expr) = N_Aggregate then
2112 Expand_Atomic_Aggregate (Expr, Etype (E));
2114 -- If the expression is a reference to a record or array object
2115 -- entity, then reset Is_True_Constant to False so that the
2116 -- compiler will not optimize away the intermediate object,
2117 -- which we need in this case for the same reason (to ensure
2118 -- that the actual assignment is atomic, rather than
2121 elsif Is_Entity_Name (Expr)
2122 and then (Is_Record_Type (Etype (Expr))
2124 Is_Array_Type (Etype (Expr)))
2126 Set_Is_True_Constant (Entity (Expr), False);
2131 -- For a subprogram, freeze all parameter types and also the return
2132 -- type (RM 13.14(14)). However skip this for internal subprograms.
2133 -- This is also the point where any extra formal parameters are
2134 -- created since we now know whether the subprogram will use
2135 -- a foreign convention.
2137 if Is_Subprogram (E) then
2138 if not Is_Internal (E) then
2141 Warn_Node : Node_Id;
2143 function Is_Fat_C_Ptr_Type (T : Entity_Id) return Boolean;
2144 -- Determines if given type entity is a fat pointer type
2145 -- used as an argument type or return type to a subprogram
2146 -- with C or C++ convention set.
2148 --------------------------
2149 -- Is_Fat_C_Access_Type --
2150 --------------------------
2152 function Is_Fat_C_Ptr_Type (T : Entity_Id) return Boolean is
2154 return (Convention (E) = Convention_C
2156 Convention (E) = Convention_CPP)
2157 and then Is_Access_Type (T)
2158 and then Esize (T) > Ttypes.System_Address_Size;
2159 end Is_Fat_C_Ptr_Type;
2162 -- Loop through formals
2164 Formal := First_Formal (E);
2165 while Present (Formal) loop
2166 F_Type := Etype (Formal);
2167 Freeze_And_Append (F_Type, Loc, Result);
2169 if Is_Private_Type (F_Type)
2170 and then Is_Private_Type (Base_Type (F_Type))
2171 and then No (Full_View (Base_Type (F_Type)))
2172 and then not Is_Generic_Type (F_Type)
2173 and then not Is_Derived_Type (F_Type)
2175 -- If the type of a formal is incomplete, subprogram
2176 -- is being frozen prematurely. Within an instance
2177 -- (but not within a wrapper package) this is an
2178 -- an artifact of our need to regard the end of an
2179 -- instantiation as a freeze point. Otherwise it is
2180 -- a definite error.
2182 -- and then not Is_Wrapper_Package (Current_Scope) ???
2185 Set_Is_Frozen (E, False);
2188 elsif not After_Last_Declaration then
2189 Error_Msg_Node_1 := F_Type;
2191 ("type& must be fully defined before this point",
2196 -- Check bad use of fat C pointer
2198 if Warn_On_Export_Import and then
2199 Is_Fat_C_Ptr_Type (F_Type)
2201 Error_Msg_Qual_Level := 1;
2203 ("?type of & does not correspond to C pointer",
2205 Error_Msg_Qual_Level := 0;
2208 -- Check for unconstrained array in exported foreign
2211 if Convention (E) in Foreign_Convention
2212 and then not Is_Imported (E)
2213 and then Is_Array_Type (F_Type)
2214 and then not Is_Constrained (F_Type)
2215 and then Warn_On_Export_Import
2217 Error_Msg_Qual_Level := 1;
2219 -- If this is an inherited operation, place the
2220 -- warning on the derived type declaration, rather
2221 -- than on the original subprogram.
2223 if Nkind (Original_Node (Parent (E))) =
2224 N_Full_Type_Declaration
2226 Warn_Node := Parent (E);
2228 if Formal = First_Formal (E) then
2230 ("?in inherited operation&", Warn_Node, E);
2233 Warn_Node := Formal;
2237 ("?type of argument& is unconstrained array",
2240 ("?foreign caller must pass bounds explicitly",
2242 Error_Msg_Qual_Level := 0;
2245 -- Ada 2005 (AI-326): Check wrong use of tag incomplete
2246 -- types with unknown discriminants. For example:
2248 -- type T (<>) is tagged;
2249 -- procedure P (X : access T); -- ERROR
2250 -- procedure P (X : T); -- ERROR
2252 if not From_With_Type (F_Type) then
2253 if Is_Access_Type (F_Type) then
2254 F_Type := Designated_Type (F_Type);
2257 if Ekind (F_Type) = E_Incomplete_Type
2258 and then Is_Tagged_Type (F_Type)
2259 and then not Is_Class_Wide_Type (F_Type)
2260 and then No (Full_View (F_Type))
2261 and then Unknown_Discriminants_Present
2263 and then No (Stored_Constraint (F_Type))
2266 ("(Ada 2005): invalid use of unconstrained tagged"
2267 & " incomplete type", E);
2269 elsif Ekind (F_Type) = E_Subprogram_Type then
2270 Freeze_And_Append (F_Type, Loc, Result);
2274 Next_Formal (Formal);
2277 -- Check return type
2279 if Ekind (E) = E_Function then
2280 Freeze_And_Append (Etype (E), Loc, Result);
2282 if Warn_On_Export_Import
2283 and then Is_Fat_C_Ptr_Type (Etype (E))
2286 ("?return type of& does not correspond to C pointer",
2289 elsif Is_Array_Type (Etype (E))
2290 and then not Is_Constrained (Etype (E))
2291 and then not Is_Imported (E)
2292 and then Convention (E) in Foreign_Convention
2293 and then Warn_On_Export_Import
2296 ("?foreign convention function& should not " &
2297 "return unconstrained array", E);
2299 -- Ada 2005 (AI-326): Check wrong use of tagged
2302 -- type T is tagged;
2303 -- function F (X : Boolean) return T; -- ERROR
2305 elsif Ekind (Etype (E)) = E_Incomplete_Type
2306 and then Is_Tagged_Type (Etype (E))
2307 and then No (Full_View (Etype (E)))
2310 ("(Ada 2005): invalid use of tagged incomplete type",
2317 -- Must freeze its parent first if it is a derived subprogram
2319 if Present (Alias (E)) then
2320 Freeze_And_Append (Alias (E), Loc, Result);
2323 -- If the return type requires a transient scope, and we are on
2324 -- a target allowing functions to return with a depressed stack
2325 -- pointer, then we mark the function as requiring this treatment.
2327 if Ekind (E) = E_Function
2328 and then Functions_Return_By_DSP_On_Target
2329 and then Requires_Transient_Scope (Etype (E))
2331 Set_Function_Returns_With_DSP (E);
2334 if not Is_Internal (E) then
2335 Freeze_Subprogram (E);
2338 -- Here for other than a subprogram or type
2341 -- If entity has a type, and it is not a generic unit, then
2342 -- freeze it first (RM 13.14(10))
2344 if Present (Etype (E))
2345 and then Ekind (E) /= E_Generic_Function
2347 Freeze_And_Append (Etype (E), Loc, Result);
2350 -- Special processing for objects created by object declaration
2352 if Nkind (Declaration_Node (E)) = N_Object_Declaration then
2354 -- For object created by object declaration, perform required
2355 -- categorization (preelaborate and pure) checks. Defer these
2356 -- checks to freeze time since pragma Import inhibits default
2357 -- initialization and thus pragma Import affects these checks.
2359 Validate_Object_Declaration (Declaration_Node (E));
2361 -- If there is an address clause, check it is valid
2363 Check_Address_Clause (E);
2365 -- For imported objects, set Is_Public unless there is also
2366 -- an address clause, which means that there is no external
2367 -- symbol needed for the Import (Is_Public may still be set
2368 -- for other unrelated reasons). Note that we delayed this
2369 -- processing till freeze time so that we can be sure not
2370 -- to set the flag if there is an address clause. If there
2371 -- is such a clause, then the only purpose of the import
2372 -- pragma is to suppress implicit initialization.
2375 and then No (Address_Clause (E))
2381 -- Check that a constant which has a pragma Volatile[_Components]
2382 -- or Atomic[_Components] also has a pragma Import (RM C.6(13))
2384 -- Note: Atomic[_Components] also sets Volatile[_Components]
2386 if Ekind (E) = E_Constant
2387 and then (Has_Volatile_Components (E) or else Is_Volatile (E))
2388 and then not Is_Imported (E)
2390 -- Make sure we actually have a pragma, and have not merely
2391 -- inherited the indication from elsewhere (e.g. an address
2392 -- clause, which is not good enough in RM terms!)
2394 if Has_Rep_Pragma (E, Name_Atomic)
2396 Has_Rep_Pragma (E, Name_Atomic_Components)
2399 ("stand alone atomic constant must be " &
2400 "imported ('R'M 'C.6(13))", E);
2402 elsif Has_Rep_Pragma (E, Name_Volatile)
2404 Has_Rep_Pragma (E, Name_Volatile_Components)
2407 ("stand alone volatile constant must be " &
2408 "imported ('R'M 'C.6(13))", E);
2412 -- Static objects require special handling
2414 if (Ekind (E) = E_Constant or else Ekind (E) = E_Variable)
2415 and then Is_Statically_Allocated (E)
2417 Freeze_Static_Object (E);
2420 -- Remaining step is to layout objects
2422 if Ekind (E) = E_Variable
2424 Ekind (E) = E_Constant
2426 Ekind (E) = E_Loop_Parameter
2434 -- Case of a type or subtype being frozen
2437 -- The type may be defined in a generic unit. This can occur when
2438 -- freezing a generic function that returns the type (which is
2439 -- defined in a parent unit). It is clearly meaningless to freeze
2440 -- this type. However, if it is a subtype, its size may be determi-
2441 -- nable and used in subsequent checks, so might as well try to
2444 if Present (Scope (E))
2445 and then Is_Generic_Unit (Scope (E))
2447 Check_Compile_Time_Size (E);
2451 -- Deal with special cases of freezing for subtype
2453 if E /= Base_Type (E) then
2455 -- If ancestor subtype present, freeze that first.
2456 -- Note that this will also get the base type frozen.
2458 Atype := Ancestor_Subtype (E);
2460 if Present (Atype) then
2461 Freeze_And_Append (Atype, Loc, Result);
2463 -- Otherwise freeze the base type of the entity before
2464 -- freezing the entity itself, (RM 13.14(15)).
2466 elsif E /= Base_Type (E) then
2467 Freeze_And_Append (Base_Type (E), Loc, Result);
2470 -- For a derived type, freeze its parent type first (RM 13.14(15))
2472 elsif Is_Derived_Type (E) then
2473 Freeze_And_Append (Etype (E), Loc, Result);
2474 Freeze_And_Append (First_Subtype (Etype (E)), Loc, Result);
2477 -- For array type, freeze index types and component type first
2478 -- before freezing the array (RM 13.14(15)).
2480 if Is_Array_Type (E) then
2482 Ctyp : constant Entity_Id := Component_Type (E);
2485 Non_Standard_Enum : Boolean := False;
2486 -- Set true if any of the index types is an enumeration
2487 -- type with a non-standard representation.
2490 Freeze_And_Append (Ctyp, Loc, Result);
2492 Indx := First_Index (E);
2493 while Present (Indx) loop
2494 Freeze_And_Append (Etype (Indx), Loc, Result);
2496 if Is_Enumeration_Type (Etype (Indx))
2497 and then Has_Non_Standard_Rep (Etype (Indx))
2499 Non_Standard_Enum := True;
2505 -- Processing that is done only for base types
2507 if Ekind (E) = E_Array_Type then
2509 -- Propagate flags for component type
2511 if Is_Controlled (Component_Type (E))
2512 or else Has_Controlled_Component (Ctyp)
2514 Set_Has_Controlled_Component (E);
2517 if Has_Unchecked_Union (Component_Type (E)) then
2518 Set_Has_Unchecked_Union (E);
2521 -- If packing was requested or if the component size was set
2522 -- explicitly, then see if bit packing is required. This
2523 -- processing is only done for base types, since all the
2524 -- representation aspects involved are type-related. This
2525 -- is not just an optimization, if we start processing the
2526 -- subtypes, they intefere with the settings on the base
2527 -- type (this is because Is_Packed has a slightly different
2528 -- meaning before and after freezing).
2535 if (Is_Packed (E) or else Has_Pragma_Pack (E))
2536 and then not Has_Atomic_Components (E)
2537 and then Known_Static_RM_Size (Ctyp)
2539 Csiz := UI_Max (RM_Size (Ctyp), 1);
2541 elsif Known_Component_Size (E) then
2542 Csiz := Component_Size (E);
2544 elsif not Known_Static_Esize (Ctyp) then
2548 Esiz := Esize (Ctyp);
2550 -- We can set the component size if it is less than
2551 -- 16, rounding it up to the next storage unit size.
2555 elsif Esiz <= 16 then
2561 -- Set component size up to match alignment if
2562 -- it would otherwise be less than the alignment.
2563 -- This deals with cases of types whose alignment
2564 -- exceeds their sizes (padded types).
2568 A : constant Uint := Alignment_In_Bits (Ctyp);
2579 if 1 <= Csiz and then Csiz <= 64 then
2581 -- We set the component size for all cases 1-64
2583 Set_Component_Size (Base_Type (E), Csiz);
2585 -- Check for base type of 8,16,32 bits, where the
2586 -- subtype has a length one less than the base type
2587 -- and is unsigned (e.g. Natural subtype of Integer)
2589 -- In such cases, if a component size was not set
2590 -- explicitly, then generate a warning.
2592 if Has_Pragma_Pack (E)
2593 and then not Has_Component_Size_Clause (E)
2595 (Csiz = 7 or else Csiz = 15 or else Csiz = 31)
2596 and then Esize (Base_Type (Ctyp)) = Csiz + 1
2598 Error_Msg_Uint_1 := Csiz;
2600 Get_Rep_Pragma (First_Subtype (E), Name_Pack);
2602 if Present (Pnod) then
2604 ("pragma Pack causes component size to be ^?",
2607 ("\use Component_Size to set desired value",
2612 -- Actual packing is not needed for 8,16,32,64
2613 -- Also not needed for 24 if alignment is 1
2619 or else (Csiz = 24 and then Alignment (Ctyp) = 1)
2621 -- Here the array was requested to be packed, but
2622 -- the packing request had no effect, so Is_Packed
2625 -- Note: semantically this means that we lose
2626 -- track of the fact that a derived type inherited
2627 -- a pack pragma that was non-effective, but that
2630 -- We regard a Pack pragma as a request to set a
2631 -- representation characteristic, and this request
2634 Set_Is_Packed (Base_Type (E), False);
2636 -- In all other cases, packing is indeed needed
2639 Set_Has_Non_Standard_Rep (Base_Type (E));
2640 Set_Is_Bit_Packed_Array (Base_Type (E));
2641 Set_Is_Packed (Base_Type (E));
2646 -- Processing that is done only for subtypes
2649 -- Acquire alignment from base type
2651 if Unknown_Alignment (E) then
2652 Set_Alignment (E, Alignment (Base_Type (E)));
2656 -- For bit-packed arrays, check the size
2658 if Is_Bit_Packed_Array (E)
2659 and then Known_Esize (E)
2663 SizC : constant Node_Id := Size_Clause (E);
2666 -- It is not clear if it is possible to have no size
2667 -- clause at this stage, but this is not worth worrying
2668 -- about. Post the error on the entity name in the size
2669 -- clause if present, else on the type entity itself.
2671 if Present (SizC) then
2672 Check_Size (Name (SizC), E, Esize (E), Discard);
2674 Check_Size (E, E, Esize (E), Discard);
2679 -- Check one common case of a size given where the array
2680 -- needs to be packed, but was not so the size cannot be
2681 -- honored. This would of course be caught by the backend,
2682 -- and indeed we don't catch all cases. The point is that
2683 -- we can give a better error message in those cases that
2684 -- we do catch with the circuitry here.
2688 Ctyp : constant Entity_Id := Component_Type (E);
2691 if Present (Size_Clause (E))
2692 and then Known_Static_Esize (E)
2693 and then not Is_Bit_Packed_Array (E)
2694 and then not Has_Pragma_Pack (E)
2695 and then Number_Dimensions (E) = 1
2696 and then not Has_Component_Size_Clause (E)
2697 and then Known_Static_Esize (Ctyp)
2699 Get_Index_Bounds (First_Index (E), Lo, Hi);
2701 if Compile_Time_Known_Value (Lo)
2702 and then Compile_Time_Known_Value (Hi)
2703 and then Known_Static_RM_Size (Ctyp)
2704 and then RM_Size (Ctyp) < 64
2707 Lov : constant Uint := Expr_Value (Lo);
2708 Hiv : constant Uint := Expr_Value (Hi);
2709 Len : constant Uint :=
2710 UI_Max (Uint_0, Hiv - Lov + 1);
2711 Rsiz : constant Uint := RM_Size (Ctyp);
2713 -- What we are looking for here is the situation
2714 -- where the Esize given would be exactly right
2715 -- if there was a pragma Pack (resulting in the
2716 -- component size being the same as the RM_Size).
2717 -- Furthermore, the component type size must be
2718 -- an odd size (not a multiple of storage unit)
2721 if Esize (E) = Len * Rsiz
2722 and then Rsiz mod System_Storage_Unit /= 0
2725 ("size given for& too small",
2726 Size_Clause (E), E);
2728 ("\explicit pragma Pack is required",
2736 -- If any of the index types was an enumeration type with
2737 -- a non-standard rep clause, then we indicate that the
2738 -- array type is always packed (even if it is not bit packed).
2740 if Non_Standard_Enum then
2741 Set_Has_Non_Standard_Rep (Base_Type (E));
2742 Set_Is_Packed (Base_Type (E));
2745 Set_Component_Alignment_If_Not_Set (E);
2747 -- If the array is packed, we must create the packed array
2748 -- type to be used to actually implement the type. This is
2749 -- only needed for real array types (not for string literal
2750 -- types, since they are present only for the front end).
2753 and then Ekind (E) /= E_String_Literal_Subtype
2755 Create_Packed_Array_Type (E);
2756 Freeze_And_Append (Packed_Array_Type (E), Loc, Result);
2758 -- Size information of packed array type is copied to the
2759 -- array type, since this is really the representation.
2761 Set_Size_Info (E, Packed_Array_Type (E));
2762 Set_RM_Size (E, RM_Size (Packed_Array_Type (E)));
2765 -- For non-packed arrays set the alignment of the array
2766 -- to the alignment of the component type if it is unknown.
2767 -- Skip this in the atomic case, since atomic arrays may
2768 -- need larger alignments.
2770 if not Is_Packed (E)
2771 and then Unknown_Alignment (E)
2772 and then Known_Alignment (Ctyp)
2773 and then Known_Static_Component_Size (E)
2774 and then Known_Static_Esize (Ctyp)
2775 and then Esize (Ctyp) = Component_Size (E)
2776 and then not Is_Atomic (E)
2778 Set_Alignment (E, Alignment (Component_Type (E)));
2782 -- For a class-wide type, the corresponding specific type is
2783 -- frozen as well (RM 13.14(15))
2785 elsif Is_Class_Wide_Type (E) then
2786 Freeze_And_Append (Root_Type (E), Loc, Result);
2788 -- If the Class_Wide_Type is an Itype (when type is the anonymous
2789 -- parent of a derived type) and it is a library-level entity,
2790 -- generate an itype reference for it. Otherwise, its first
2791 -- explicit reference may be in an inner scope, which will be
2792 -- rejected by the back-end.
2795 and then Is_Compilation_Unit (Scope (E))
2798 Ref : constant Node_Id := Make_Itype_Reference (Loc);
2803 Result := New_List (Ref);
2805 Append (Ref, Result);
2810 -- The equivalent type associated with a class-wide subtype
2811 -- needs to be frozen to ensure that its layout is done.
2812 -- Class-wide subtypes are currently only frozen on targets
2813 -- requiring front-end layout (see New_Class_Wide_Subtype
2814 -- and Make_CW_Equivalent_Type in exp_util.adb).
2816 if Ekind (E) = E_Class_Wide_Subtype
2817 and then Present (Equivalent_Type (E))
2819 Freeze_And_Append (Equivalent_Type (E), Loc, Result);
2822 -- For a record (sub)type, freeze all the component types (RM
2823 -- 13.14(15). We test for E_Record_(sub)Type here, rather than
2824 -- using Is_Record_Type, because we don't want to attempt the
2825 -- freeze for the case of a private type with record extension
2826 -- (we will do that later when the full type is frozen).
2828 elsif Ekind (E) = E_Record_Type
2829 or else Ekind (E) = E_Record_Subtype
2831 Freeze_Record_Type (E);
2833 -- For a concurrent type, freeze corresponding record type. This
2834 -- does not correpond to any specific rule in the RM, but the
2835 -- record type is essentially part of the concurrent type.
2836 -- Freeze as well all local entities. This includes record types
2837 -- created for entry parameter blocks, and whatever local entities
2838 -- may appear in the private part.
2840 elsif Is_Concurrent_Type (E) then
2841 if Present (Corresponding_Record_Type (E)) then
2843 (Corresponding_Record_Type (E), Loc, Result);
2846 Comp := First_Entity (E);
2848 while Present (Comp) loop
2849 if Is_Type (Comp) then
2850 Freeze_And_Append (Comp, Loc, Result);
2852 elsif (Ekind (Comp)) /= E_Function then
2853 if Is_Itype (Etype (Comp))
2854 and then Underlying_Type (Scope (Etype (Comp))) = E
2856 Undelay_Type (Etype (Comp));
2859 Freeze_And_Append (Etype (Comp), Loc, Result);
2865 -- Private types are required to point to the same freeze node as
2866 -- their corresponding full views. The freeze node itself has to
2867 -- point to the partial view of the entity (because from the partial
2868 -- view, we can retrieve the full view, but not the reverse).
2869 -- However, in order to freeze correctly, we need to freeze the full
2870 -- view. If we are freezing at the end of a scope (or within the
2871 -- scope of the private type), the partial and full views will have
2872 -- been swapped, the full view appears first in the entity chain and
2873 -- the swapping mechanism ensures that the pointers are properly set
2876 -- If we encounter the partial view before the full view (e.g. when
2877 -- freezing from another scope), we freeze the full view, and then
2878 -- set the pointers appropriately since we cannot rely on swapping to
2879 -- fix things up (subtypes in an outer scope might not get swapped).
2881 elsif Is_Incomplete_Or_Private_Type (E)
2882 and then not Is_Generic_Type (E)
2884 -- Case of full view present
2886 if Present (Full_View (E)) then
2888 -- If full view has already been frozen, then no further
2889 -- processing is required
2891 if Is_Frozen (Full_View (E)) then
2893 Set_Has_Delayed_Freeze (E, False);
2894 Set_Freeze_Node (E, Empty);
2895 Check_Debug_Info_Needed (E);
2897 -- Otherwise freeze full view and patch the pointers so that
2898 -- the freeze node will elaborate both views in the back-end.
2902 Full : constant Entity_Id := Full_View (E);
2905 if Is_Private_Type (Full)
2906 and then Present (Underlying_Full_View (Full))
2909 (Underlying_Full_View (Full), Loc, Result);
2912 Freeze_And_Append (Full, Loc, Result);
2914 if Has_Delayed_Freeze (E) then
2915 F_Node := Freeze_Node (Full);
2917 if Present (F_Node) then
2918 Set_Freeze_Node (E, F_Node);
2919 Set_Entity (F_Node, E);
2922 -- {Incomplete,Private}_Subtypes
2923 -- with Full_Views constrained by discriminants
2925 Set_Has_Delayed_Freeze (E, False);
2926 Set_Freeze_Node (E, Empty);
2931 Check_Debug_Info_Needed (E);
2934 -- AI-117 requires that the convention of a partial view be the
2935 -- same as the convention of the full view. Note that this is a
2936 -- recognized breach of privacy, but it's essential for logical
2937 -- consistency of representation, and the lack of a rule in
2938 -- RM95 was an oversight.
2940 Set_Convention (E, Convention (Full_View (E)));
2942 Set_Size_Known_At_Compile_Time (E,
2943 Size_Known_At_Compile_Time (Full_View (E)));
2945 -- Size information is copied from the full view to the
2946 -- incomplete or private view for consistency
2948 -- We skip this is the full view is not a type. This is very
2949 -- strange of course, and can only happen as a result of
2950 -- certain illegalities, such as a premature attempt to derive
2951 -- from an incomplete type.
2953 if Is_Type (Full_View (E)) then
2954 Set_Size_Info (E, Full_View (E));
2955 Set_RM_Size (E, RM_Size (Full_View (E)));
2960 -- Case of no full view present. If entity is derived or subtype,
2961 -- it is safe to freeze, correctness depends on the frozen status
2962 -- of parent. Otherwise it is either premature usage, or a Taft
2963 -- amendment type, so diagnosis is at the point of use and the
2964 -- type might be frozen later.
2966 elsif E /= Base_Type (E)
2967 or else Is_Derived_Type (E)
2972 Set_Is_Frozen (E, False);
2976 -- For access subprogram, freeze types of all formals, the return
2977 -- type was already frozen, since it is the Etype of the function.
2979 elsif Ekind (E) = E_Subprogram_Type then
2980 Formal := First_Formal (E);
2981 while Present (Formal) loop
2982 Freeze_And_Append (Etype (Formal), Loc, Result);
2983 Next_Formal (Formal);
2986 -- If the return type requires a transient scope, and we are on
2987 -- a target allowing functions to return with a depressed stack
2988 -- pointer, then we mark the function as requiring this treatment.
2990 if Functions_Return_By_DSP_On_Target
2991 and then Requires_Transient_Scope (Etype (E))
2993 Set_Function_Returns_With_DSP (E);
2996 Freeze_Subprogram (E);
2998 -- AI-326: Check wrong use of tag incomplete type
3000 -- type T is tagged;
3001 -- type Acc is access function (X : T) return T; -- ERROR
3003 if Ekind (Etype (E)) = E_Incomplete_Type
3004 and then Is_Tagged_Type (Etype (E))
3005 and then No (Full_View (Etype (E)))
3008 ("(Ada 2005): invalid use of tagged incomplete type", E);
3011 -- For access to a protected subprogram, freeze the equivalent type
3012 -- (however this is not set if we are not generating code or if this
3013 -- is an anonymous type used just for resolution).
3015 elsif Ekind (E) = E_Access_Protected_Subprogram_Type then
3017 -- AI-326: Check wrong use of tagged incomplete types
3019 -- type T is tagged;
3020 -- type As3D is access protected
3021 -- function (X : Float) return T; -- ERROR
3027 Etyp := Etype (Directly_Designated_Type (E));
3029 if Is_Class_Wide_Type (Etyp) then
3030 Etyp := Etype (Etyp);
3033 if Ekind (Etyp) = E_Incomplete_Type
3034 and then Is_Tagged_Type (Etyp)
3035 and then No (Full_View (Etyp))
3038 ("(Ada 2005): invalid use of tagged incomplete type", E);
3042 if Present (Equivalent_Type (E)) then
3043 Freeze_And_Append (Equivalent_Type (E), Loc, Result);
3047 -- Generic types are never seen by the back-end, and are also not
3048 -- processed by the expander (since the expander is turned off for
3049 -- generic processing), so we never need freeze nodes for them.
3051 if Is_Generic_Type (E) then
3055 -- Some special processing for non-generic types to complete
3056 -- representation details not known till the freeze point.
3058 if Is_Fixed_Point_Type (E) then
3059 Freeze_Fixed_Point_Type (E);
3061 -- Some error checks required for ordinary fixed-point type. Defer
3062 -- these till the freeze-point since we need the small and range
3063 -- values. We only do these checks for base types
3065 if Is_Ordinary_Fixed_Point_Type (E)
3066 and then E = Base_Type (E)
3068 if Small_Value (E) < Ureal_2_M_80 then
3069 Error_Msg_Name_1 := Name_Small;
3071 ("`&''%` is too small, minimum is 2.0'*'*(-80)", E);
3073 elsif Small_Value (E) > Ureal_2_80 then
3074 Error_Msg_Name_1 := Name_Small;
3076 ("`&''%` is too large, maximum is 2.0'*'*80", E);
3079 if Expr_Value_R (Type_Low_Bound (E)) < Ureal_M_10_36 then
3080 Error_Msg_Name_1 := Name_First;
3082 ("`&''%` is too small, minimum is -10.0'*'*36", E);
3085 if Expr_Value_R (Type_High_Bound (E)) > Ureal_10_36 then
3086 Error_Msg_Name_1 := Name_Last;
3088 ("`&''%` is too large, maximum is 10.0'*'*36", E);
3092 elsif Is_Enumeration_Type (E) then
3093 Freeze_Enumeration_Type (E);
3095 elsif Is_Integer_Type (E) then
3096 Adjust_Esize_For_Alignment (E);
3098 elsif Is_Access_Type (E) then
3100 -- Check restriction for standard storage pool
3102 if No (Associated_Storage_Pool (E)) then
3103 Check_Restriction (No_Standard_Storage_Pools, E);
3106 -- Deal with error message for pure access type. This is not an
3107 -- error in Ada 2005 if there is no pool (see AI-366).
3109 if Is_Pure_Unit_Access_Type (E)
3110 and then (Ada_Version < Ada_05
3111 or else not No_Pool_Assigned (E))
3113 Error_Msg_N ("named access type not allowed in pure unit", E);
3117 -- Case of composite types
3119 if Is_Composite_Type (E) then
3121 -- AI-117 requires that all new primitives of a tagged type must
3122 -- inherit the convention of the full view of the type. Inherited
3123 -- and overriding operations are defined to inherit the convention
3124 -- of their parent or overridden subprogram (also specified in
3125 -- AI-117), which will have occurred earlier (in Derive_Subprogram
3126 -- and New_Overloaded_Entity). Here we set the convention of
3127 -- primitives that are still convention Ada, which will ensure
3128 -- that any new primitives inherit the type's convention.
3129 -- Class-wide types can have a foreign convention inherited from
3130 -- their specific type, but are excluded from this since they
3131 -- don't have any associated primitives.
3133 if Is_Tagged_Type (E)
3134 and then not Is_Class_Wide_Type (E)
3135 and then Convention (E) /= Convention_Ada
3138 Prim_List : constant Elist_Id := Primitive_Operations (E);
3141 Prim := First_Elmt (Prim_List);
3142 while Present (Prim) loop
3143 if Convention (Node (Prim)) = Convention_Ada then
3144 Set_Convention (Node (Prim), Convention (E));
3153 -- Generate primitive operation references for a tagged type
3155 if Is_Tagged_Type (E)
3156 and then not Is_Class_Wide_Type (E)
3159 Prim_List : Elist_Id;
3167 if Ekind (E) = E_Protected_Subtype
3168 or else Ekind (E) = E_Task_Subtype
3175 -- Ada 2005 (AI-345): In case of concurrent type generate
3176 -- reference to the wrapper that allow us to dispatch calls
3177 -- through their implemented abstract interface types.
3179 -- The check for Present here is to protect against previously
3180 -- reported critical errors.
3182 if Is_Concurrent_Type (Aux_E)
3183 and then Present (Corresponding_Record_Type (Aux_E))
3185 pragma Assert (not Is_Empty_Elmt_List
3186 (Abstract_Interfaces
3187 (Corresponding_Record_Type (Aux_E))));
3189 Prim_List := Primitive_Operations
3190 (Corresponding_Record_Type (Aux_E));
3192 Prim_List := Primitive_Operations (Aux_E);
3195 -- Loop to generate references for primitive operations
3197 if Present (Prim_List) then
3198 Prim := First_Elmt (Prim_List);
3199 while Present (Prim) loop
3201 -- If the operation is derived, get the original for
3202 -- cross-reference purposes (it is the original for
3203 -- which we want the xref, and for which the comes
3204 -- from source test needs to be performed).
3207 while Present (Alias (Ent)) loop
3211 Generate_Reference (E, Ent, 'p', Set_Ref => False);
3218 -- Now that all types from which E may depend are frozen, see if the
3219 -- size is known at compile time, if it must be unsigned, or if
3220 -- strict alignent is required
3222 Check_Compile_Time_Size (E);
3223 Check_Unsigned_Type (E);
3225 if Base_Type (E) = E then
3226 Check_Strict_Alignment (E);
3229 -- Do not allow a size clause for a type which does not have a size
3230 -- that is known at compile time
3232 if Has_Size_Clause (E)
3233 and then not Size_Known_At_Compile_Time (E)
3235 -- Supress this message if errors posted on E, even if we are
3236 -- in all errors mode, since this is often a junk message
3238 if not Error_Posted (E) then
3240 ("size clause not allowed for variable length type",
3245 -- Remaining process is to set/verify the representation information,
3246 -- in particular the size and alignment values. This processing is
3247 -- not required for generic types, since generic types do not play
3248 -- any part in code generation, and so the size and alignment values
3249 -- for such types are irrelevant.
3251 if Is_Generic_Type (E) then
3254 -- Otherwise we call the layout procedure
3260 -- End of freeze processing for type entities
3263 -- Here is where we logically freeze the current entity. If it has a
3264 -- freeze node, then this is the point at which the freeze node is
3265 -- linked into the result list.
3267 if Has_Delayed_Freeze (E) then
3269 -- If a freeze node is already allocated, use it, otherwise allocate
3270 -- a new one. The preallocation happens in the case of anonymous base
3271 -- types, where we preallocate so that we can set First_Subtype_Link.
3272 -- Note that we reset the Sloc to the current freeze location.
3274 if Present (Freeze_Node (E)) then
3275 F_Node := Freeze_Node (E);
3276 Set_Sloc (F_Node, Loc);
3279 F_Node := New_Node (N_Freeze_Entity, Loc);
3280 Set_Freeze_Node (E, F_Node);
3281 Set_Access_Types_To_Process (F_Node, No_Elist);
3282 Set_TSS_Elist (F_Node, No_Elist);
3283 Set_Actions (F_Node, No_List);
3286 Set_Entity (F_Node, E);
3288 if Result = No_List then
3289 Result := New_List (F_Node);
3291 Append (F_Node, Result);
3294 -- A final pass over record types with discriminants. If the type
3295 -- has an incomplete declaration, there may be constrained access
3296 -- subtypes declared elsewhere, which do not depend on the discrimi-
3297 -- nants of the type, and which are used as component types (i.e.
3298 -- the full view is a recursive type). The designated types of these
3299 -- subtypes can only be elaborated after the type itself, and they
3300 -- need an itype reference.
3302 if Ekind (E) = E_Record_Type
3303 and then Has_Discriminants (E)
3311 Comp := First_Component (E);
3313 while Present (Comp) loop
3314 Typ := Etype (Comp);
3316 if Ekind (Comp) = E_Component
3317 and then Is_Access_Type (Typ)
3318 and then Scope (Typ) /= E
3319 and then Base_Type (Designated_Type (Typ)) = E
3320 and then Is_Itype (Designated_Type (Typ))
3322 IR := Make_Itype_Reference (Sloc (Comp));
3323 Set_Itype (IR, Designated_Type (Typ));
3324 Append (IR, Result);
3327 Next_Component (Comp);
3333 -- When a type is frozen, the first subtype of the type is frozen as
3334 -- well (RM 13.14(15)). This has to be done after freezing the type,
3335 -- since obviously the first subtype depends on its own base type.
3338 Freeze_And_Append (First_Subtype (E), Loc, Result);
3340 -- If we just froze a tagged non-class wide record, then freeze the
3341 -- corresponding class-wide type. This must be done after the tagged
3342 -- type itself is frozen, because the class-wide type refers to the
3343 -- tagged type which generates the class.
3345 if Is_Tagged_Type (E)
3346 and then not Is_Class_Wide_Type (E)
3347 and then Present (Class_Wide_Type (E))
3349 Freeze_And_Append (Class_Wide_Type (E), Loc, Result);
3353 Check_Debug_Info_Needed (E);
3355 -- Special handling for subprograms
3357 if Is_Subprogram (E) then
3359 -- If subprogram has address clause then reset Is_Public flag, since
3360 -- we do not want the backend to generate external references.
3362 if Present (Address_Clause (E))
3363 and then not Is_Library_Level_Entity (E)
3365 Set_Is_Public (E, False);
3367 -- If no address clause and not intrinsic, then for imported
3368 -- subprogram in main unit, generate descriptor if we are in
3369 -- Propagate_Exceptions mode.
3371 elsif Propagate_Exceptions
3372 and then Is_Imported (E)
3373 and then not Is_Intrinsic_Subprogram (E)
3374 and then Convention (E) /= Convention_Stubbed
3376 if Result = No_List then
3377 Result := Empty_List;
3385 -----------------------------
3386 -- Freeze_Enumeration_Type --
3387 -----------------------------
3389 procedure Freeze_Enumeration_Type (Typ : Entity_Id) is
3391 if Has_Foreign_Convention (Typ)
3392 and then not Has_Size_Clause (Typ)
3393 and then Esize (Typ) < Standard_Integer_Size
3395 Init_Esize (Typ, Standard_Integer_Size);
3397 Adjust_Esize_For_Alignment (Typ);
3399 end Freeze_Enumeration_Type;
3401 -----------------------
3402 -- Freeze_Expression --
3403 -----------------------
3405 procedure Freeze_Expression (N : Node_Id) is
3406 In_Def_Exp : constant Boolean := In_Default_Expression;
3409 Desig_Typ : Entity_Id;
3413 Freeze_Outside : Boolean := False;
3414 -- This flag is set true if the entity must be frozen outside the
3415 -- current subprogram. This happens in the case of expander generated
3416 -- subprograms (_Init_Proc, _Input, _Output, _Read, _Write) which do
3417 -- not freeze all entities like other bodies, but which nevertheless
3418 -- may reference entities that have to be frozen before the body and
3419 -- obviously cannot be frozen inside the body.
3421 function In_Exp_Body (N : Node_Id) return Boolean;
3422 -- Given an N_Handled_Sequence_Of_Statements node N, determines whether
3423 -- it is the handled statement sequence of an expander-generated
3424 -- subprogram (init proc, or stream subprogram). If so, it returns
3425 -- True, otherwise False.
3431 function In_Exp_Body (N : Node_Id) return Boolean is
3435 if Nkind (N) = N_Subprogram_Body then
3441 if Nkind (P) /= N_Subprogram_Body then
3445 P := Defining_Unit_Name (Specification (P));
3447 if Nkind (P) = N_Defining_Identifier
3448 and then (Is_Init_Proc (P) or else
3449 Is_TSS (P, TSS_Stream_Input) or else
3450 Is_TSS (P, TSS_Stream_Output) or else
3451 Is_TSS (P, TSS_Stream_Read) or else
3452 Is_TSS (P, TSS_Stream_Write))
3461 -- Start of processing for Freeze_Expression
3464 -- Immediate return if freezing is inhibited. This flag is set by the
3465 -- analyzer to stop freezing on generated expressions that would cause
3466 -- freezing if they were in the source program, but which are not
3467 -- supposed to freeze, since they are created.
3469 if Must_Not_Freeze (N) then
3473 -- If expression is non-static, then it does not freeze in a default
3474 -- expression, see section "Handling of Default Expressions" in the
3475 -- spec of package Sem for further details. Note that we have to
3476 -- make sure that we actually have a real expression (if we have
3477 -- a subtype indication, we can't test Is_Static_Expression!)
3480 and then Nkind (N) in N_Subexpr
3481 and then not Is_Static_Expression (N)
3486 -- Freeze type of expression if not frozen already
3490 if Nkind (N) in N_Has_Etype then
3491 if not Is_Frozen (Etype (N)) then
3494 -- Base type may be an derived numeric type that is frozen at
3495 -- the point of declaration, but first_subtype is still unfrozen.
3497 elsif not Is_Frozen (First_Subtype (Etype (N))) then
3498 Typ := First_Subtype (Etype (N));
3502 -- For entity name, freeze entity if not frozen already. A special
3503 -- exception occurs for an identifier that did not come from source.
3504 -- We don't let such identifiers freeze a non-internal entity, i.e.
3505 -- an entity that did come from source, since such an identifier was
3506 -- generated by the expander, and cannot have any semantic effect on
3507 -- the freezing semantics. For example, this stops the parameter of
3508 -- an initialization procedure from freezing the variable.
3510 if Is_Entity_Name (N)
3511 and then not Is_Frozen (Entity (N))
3512 and then (Nkind (N) /= N_Identifier
3513 or else Comes_From_Source (N)
3514 or else not Comes_From_Source (Entity (N)))
3521 -- For an allocator freeze designated type if not frozen already
3523 -- For an aggregate whose component type is an access type, freeze the
3524 -- designated type now, so that its freeze does not appear within the
3525 -- loop that might be created in the expansion of the aggregate. If the
3526 -- designated type is a private type without full view, the expression
3527 -- cannot contain an allocator, so the type is not frozen.
3533 Desig_Typ := Designated_Type (Etype (N));
3536 if Is_Array_Type (Etype (N))
3537 and then Is_Access_Type (Component_Type (Etype (N)))
3539 Desig_Typ := Designated_Type (Component_Type (Etype (N)));
3542 when N_Selected_Component |
3543 N_Indexed_Component |
3546 if Is_Access_Type (Etype (Prefix (N))) then
3547 Desig_Typ := Designated_Type (Etype (Prefix (N)));
3554 if Desig_Typ /= Empty
3555 and then (Is_Frozen (Desig_Typ)
3556 or else (not Is_Fully_Defined (Desig_Typ)))
3561 -- All done if nothing needs freezing
3565 and then No (Desig_Typ)
3570 -- Loop for looking at the right place to insert the freeze nodes
3571 -- exiting from the loop when it is appropriate to insert the freeze
3572 -- node before the current node P.
3574 -- Also checks some special exceptions to the freezing rules. These
3575 -- cases result in a direct return, bypassing the freeze action.
3579 Parent_P := Parent (P);
3581 -- If we don't have a parent, then we are not in a well-formed tree.
3582 -- This is an unusual case, but there are some legitimate situations
3583 -- in which this occurs, notably when the expressions in the range of
3584 -- a type declaration are resolved. We simply ignore the freeze
3585 -- request in this case. Is this right ???
3587 if No (Parent_P) then
3591 -- See if we have got to an appropriate point in the tree
3593 case Nkind (Parent_P) is
3595 -- A special test for the exception of (RM 13.14(8)) for the case
3596 -- of per-object expressions (RM 3.8(18)) occurring in component
3597 -- definition or a discrete subtype definition. Note that we test
3598 -- for a component declaration which includes both cases we are
3599 -- interested in, and furthermore the tree does not have explicit
3600 -- nodes for either of these two constructs.
3602 when N_Component_Declaration =>
3604 -- The case we want to test for here is an identifier that is
3605 -- a per-object expression, this is either a discriminant that
3606 -- appears in a context other than the component declaration
3607 -- or it is a reference to the type of the enclosing construct.
3609 -- For either of these cases, we skip the freezing
3611 if not In_Default_Expression
3612 and then Nkind (N) = N_Identifier
3613 and then (Present (Entity (N)))
3615 -- We recognize the discriminant case by just looking for
3616 -- a reference to a discriminant. It can only be one for
3617 -- the enclosing construct. Skip freezing in this case.
3619 if Ekind (Entity (N)) = E_Discriminant then
3622 -- For the case of a reference to the enclosing record,
3623 -- (or task or protected type), we look for a type that
3624 -- matches the current scope.
3626 elsif Entity (N) = Current_Scope then
3631 -- If we have an enumeration literal that appears as the choice in
3632 -- the aggregate of an enumeration representation clause, then
3633 -- freezing does not occur (RM 13.14(10)).
3635 when N_Enumeration_Representation_Clause =>
3637 -- The case we are looking for is an enumeration literal
3639 if (Nkind (N) = N_Identifier or Nkind (N) = N_Character_Literal)
3640 and then Is_Enumeration_Type (Etype (N))
3642 -- If enumeration literal appears directly as the choice,
3643 -- do not freeze (this is the normal non-overloade case)
3645 if Nkind (Parent (N)) = N_Component_Association
3646 and then First (Choices (Parent (N))) = N
3650 -- If enumeration literal appears as the name of function
3651 -- which is the choice, then also do not freeze. This
3652 -- happens in the overloaded literal case, where the
3653 -- enumeration literal is temporarily changed to a function
3654 -- call for overloading analysis purposes.
3656 elsif Nkind (Parent (N)) = N_Function_Call
3658 Nkind (Parent (Parent (N))) = N_Component_Association
3660 First (Choices (Parent (Parent (N)))) = Parent (N)
3666 -- Normally if the parent is a handled sequence of statements,
3667 -- then the current node must be a statement, and that is an
3668 -- appropriate place to insert a freeze node.
3670 when N_Handled_Sequence_Of_Statements =>
3672 -- An exception occurs when the sequence of statements is for
3673 -- an expander generated body that did not do the usual freeze
3674 -- all operation. In this case we usually want to freeze
3675 -- outside this body, not inside it, and we skip past the
3676 -- subprogram body that we are inside.
3678 if In_Exp_Body (Parent_P) then
3680 -- However, we *do* want to freeze at this point if we have
3681 -- an entity to freeze, and that entity is declared *inside*
3682 -- the body of the expander generated procedure. This case
3683 -- is recognized by the scope of the type, which is either
3684 -- the spec for some enclosing body, or (in the case of
3685 -- init_procs, for which there are no separate specs) the
3689 Subp : constant Node_Id := Parent (Parent_P);
3693 if Nkind (Subp) = N_Subprogram_Body then
3694 Cspc := Corresponding_Spec (Subp);
3696 if (Present (Typ) and then Scope (Typ) = Cspc)
3698 (Present (Nam) and then Scope (Nam) = Cspc)
3703 and then Scope (Typ) = Current_Scope
3704 and then Current_Scope = Defining_Entity (Subp)
3711 -- If not that exception to the exception, then this is
3712 -- where we delay the freeze till outside the body.
3714 Parent_P := Parent (Parent_P);
3715 Freeze_Outside := True;
3717 -- Here if normal case where we are in handled statement
3718 -- sequence and want to do the insertion right there.
3724 -- If parent is a body or a spec or a block, then the current node
3725 -- is a statement or declaration and we can insert the freeze node
3728 when N_Package_Specification |
3734 N_Block_Statement => exit;
3736 -- The expander is allowed to define types in any statements list,
3737 -- so any of the following parent nodes also mark a freezing point
3738 -- if the actual node is in a list of statements or declarations.
3740 when N_Exception_Handler |
3743 N_Case_Statement_Alternative |
3744 N_Compilation_Unit_Aux |
3745 N_Selective_Accept |
3746 N_Accept_Alternative |
3747 N_Delay_Alternative |
3748 N_Conditional_Entry_Call |
3749 N_Entry_Call_Alternative |
3750 N_Triggering_Alternative |
3754 exit when Is_List_Member (P);
3756 -- Note: The N_Loop_Statement is a special case. A type that
3757 -- appears in the source can never be frozen in a loop (this
3758 -- occurs only because of a loop expanded by the expander), so we
3759 -- keep on going. Otherwise we terminate the search. Same is true
3760 -- of any entity which comes from source. (if they have predefined
3761 -- type, that type does not appear to come from source, but the
3762 -- entity should not be frozen here).
3764 when N_Loop_Statement =>
3765 exit when not Comes_From_Source (Etype (N))
3766 and then (No (Nam) or else not Comes_From_Source (Nam));
3768 -- For all other cases, keep looking at parents
3774 -- We fall through the case if we did not yet find the proper
3775 -- place in the free for inserting the freeze node, so climb!
3780 -- If the expression appears in a record or an initialization procedure,
3781 -- the freeze nodes are collected and attached to the current scope, to
3782 -- be inserted and analyzed on exit from the scope, to insure that
3783 -- generated entities appear in the correct scope. If the expression is
3784 -- a default for a discriminant specification, the scope is still void.
3785 -- The expression can also appear in the discriminant part of a private
3786 -- or concurrent type.
3788 -- If the expression appears in a constrained subcomponent of an
3789 -- enclosing record declaration, the freeze nodes must be attached to
3790 -- the outer record type so they can eventually be placed in the
3791 -- enclosing declaration list.
3793 -- The other case requiring this special handling is if we are in a
3794 -- default expression, since in that case we are about to freeze a
3795 -- static type, and the freeze scope needs to be the outer scope, not
3796 -- the scope of the subprogram with the default parameter.
3798 -- For default expressions in generic units, the Move_Freeze_Nodes
3799 -- mechanism (see sem_ch12.adb) takes care of placing them at the proper
3800 -- place, after the generic unit.
3802 if (In_Def_Exp and not Inside_A_Generic)
3803 or else Freeze_Outside
3804 or else (Is_Type (Current_Scope)
3805 and then (not Is_Concurrent_Type (Current_Scope)
3806 or else not Has_Completion (Current_Scope)))
3807 or else Ekind (Current_Scope) = E_Void
3810 Loc : constant Source_Ptr := Sloc (Current_Scope);
3811 Freeze_Nodes : List_Id := No_List;
3812 Pos : Int := Scope_Stack.Last;
3815 if Present (Desig_Typ) then
3816 Freeze_And_Append (Desig_Typ, Loc, Freeze_Nodes);
3819 if Present (Typ) then
3820 Freeze_And_Append (Typ, Loc, Freeze_Nodes);
3823 if Present (Nam) then
3824 Freeze_And_Append (Nam, Loc, Freeze_Nodes);
3827 -- The current scope may be that of a constrained component of
3828 -- an enclosing record declaration, which is above the current
3829 -- scope in the scope stack.
3831 if Is_Record_Type (Scope (Current_Scope)) then
3835 if Is_Non_Empty_List (Freeze_Nodes) then
3836 if No (Scope_Stack.Table (Pos).Pending_Freeze_Actions) then
3837 Scope_Stack.Table (Pos).Pending_Freeze_Actions :=
3840 Append_List (Freeze_Nodes, Scope_Stack.Table
3841 (Pos).Pending_Freeze_Actions);
3849 -- Now we have the right place to do the freezing. First, a special
3850 -- adjustment, if we are in default expression analysis mode, these
3851 -- freeze actions must not be thrown away (normally all inserted actions
3852 -- are thrown away in this mode. However, the freeze actions are from
3853 -- static expressions and one of the important reasons we are doing this
3854 -- special analysis is to get these freeze actions. Therefore we turn
3855 -- off the In_Default_Expression mode to propagate these freeze actions.
3856 -- This also means they get properly analyzed and expanded.
3858 In_Default_Expression := False;
3860 -- Freeze the designated type of an allocator (RM 13.14(13))
3862 if Present (Desig_Typ) then
3863 Freeze_Before (P, Desig_Typ);
3866 -- Freeze type of expression (RM 13.14(10)). Note that we took care of
3867 -- the enumeration representation clause exception in the loop above.
3869 if Present (Typ) then
3870 Freeze_Before (P, Typ);
3873 -- Freeze name if one is present (RM 13.14(11))
3875 if Present (Nam) then
3876 Freeze_Before (P, Nam);
3879 In_Default_Expression := In_Def_Exp;
3880 end Freeze_Expression;
3882 -----------------------------
3883 -- Freeze_Fixed_Point_Type --
3884 -----------------------------
3886 -- Certain fixed-point types and subtypes, including implicit base types
3887 -- and declared first subtypes, have not yet set up a range. This is
3888 -- because the range cannot be set until the Small and Size values are
3889 -- known, and these are not known till the type is frozen.
3891 -- To signal this case, Scalar_Range contains an unanalyzed syntactic range
3892 -- whose bounds are unanalyzed real literals. This routine will recognize
3893 -- this case, and transform this range node into a properly typed range
3894 -- with properly analyzed and resolved values.
3896 procedure Freeze_Fixed_Point_Type (Typ : Entity_Id) is
3897 Rng : constant Node_Id := Scalar_Range (Typ);
3898 Lo : constant Node_Id := Low_Bound (Rng);
3899 Hi : constant Node_Id := High_Bound (Rng);
3900 Btyp : constant Entity_Id := Base_Type (Typ);
3901 Brng : constant Node_Id := Scalar_Range (Btyp);
3902 BLo : constant Node_Id := Low_Bound (Brng);
3903 BHi : constant Node_Id := High_Bound (Brng);
3904 Small : constant Ureal := Small_Value (Typ);
3911 function Fsize (Lov, Hiv : Ureal) return Nat;
3912 -- Returns size of type with given bounds. Also leaves these
3913 -- bounds set as the current bounds of the Typ.
3919 function Fsize (Lov, Hiv : Ureal) return Nat is
3921 Set_Realval (Lo, Lov);
3922 Set_Realval (Hi, Hiv);
3923 return Minimum_Size (Typ);
3926 -- Start of processing for Freeze_Fixed_Point_Type
3929 -- If Esize of a subtype has not previously been set, set it now
3931 if Unknown_Esize (Typ) then
3932 Atype := Ancestor_Subtype (Typ);
3934 if Present (Atype) then
3935 Set_Esize (Typ, Esize (Atype));
3937 Set_Esize (Typ, Esize (Base_Type (Typ)));
3941 -- Immediate return if the range is already analyzed. This means that
3942 -- the range is already set, and does not need to be computed by this
3945 if Analyzed (Rng) then
3949 -- Immediate return if either of the bounds raises Constraint_Error
3951 if Raises_Constraint_Error (Lo)
3952 or else Raises_Constraint_Error (Hi)
3957 Loval := Realval (Lo);
3958 Hival := Realval (Hi);
3960 -- Ordinary fixed-point case
3962 if Is_Ordinary_Fixed_Point_Type (Typ) then
3964 -- For the ordinary fixed-point case, we are allowed to fudge the
3965 -- end-points up or down by small. Generally we prefer to fudge up,
3966 -- i.e. widen the bounds for non-model numbers so that the end points
3967 -- are included. However there are cases in which this cannot be
3968 -- done, and indeed cases in which we may need to narrow the bounds.
3969 -- The following circuit makes the decision.
3971 -- Note: our terminology here is that Incl_EP means that the bounds
3972 -- are widened by Small if necessary to include the end points, and
3973 -- Excl_EP means that the bounds are narrowed by Small to exclude the
3974 -- end-points if this reduces the size.
3976 -- Note that in the Incl case, all we care about is including the
3977 -- end-points. In the Excl case, we want to narrow the bounds as
3978 -- much as permitted by the RM, to give the smallest possible size.
3981 Loval_Incl_EP : Ureal;
3982 Hival_Incl_EP : Ureal;
3984 Loval_Excl_EP : Ureal;
3985 Hival_Excl_EP : Ureal;
3991 First_Subt : Entity_Id;
3996 -- First step. Base types are required to be symmetrical. Right
3997 -- now, the base type range is a copy of the first subtype range.
3998 -- This will be corrected before we are done, but right away we
3999 -- need to deal with the case where both bounds are non-negative.
4000 -- In this case, we set the low bound to the negative of the high
4001 -- bound, to make sure that the size is computed to include the
4002 -- required sign. Note that we do not need to worry about the
4003 -- case of both bounds negative, because the sign will be dealt
4004 -- with anyway. Furthermore we can't just go making such a bound
4005 -- symmetrical, since in a twos-complement system, there is an
4006 -- extra negative value which could not be accomodated on the
4010 and then not UR_Is_Negative (Loval)
4011 and then Hival > Loval
4014 Set_Realval (Lo, Loval);
4017 -- Compute the fudged bounds. If the number is a model number,
4018 -- then we do nothing to include it, but we are allowed to backoff
4019 -- to the next adjacent model number when we exclude it. If it is
4020 -- not a model number then we straddle the two values with the
4021 -- model numbers on either side.
4023 Model_Num := UR_Trunc (Loval / Small) * Small;
4025 if Loval = Model_Num then
4026 Loval_Incl_EP := Model_Num;
4028 Loval_Incl_EP := Model_Num - Small;
4031 -- The low value excluding the end point is Small greater, but
4032 -- we do not do this exclusion if the low value is positive,
4033 -- since it can't help the size and could actually hurt by
4034 -- crossing the high bound.
4036 if UR_Is_Negative (Loval_Incl_EP) then
4037 Loval_Excl_EP := Loval_Incl_EP + Small;
4039 Loval_Excl_EP := Loval_Incl_EP;
4042 -- Similar processing for upper bound and high value
4044 Model_Num := UR_Trunc (Hival / Small) * Small;
4046 if Hival = Model_Num then
4047 Hival_Incl_EP := Model_Num;
4049 Hival_Incl_EP := Model_Num + Small;
4052 if UR_Is_Positive (Hival_Incl_EP) then
4053 Hival_Excl_EP := Hival_Incl_EP - Small;
4055 Hival_Excl_EP := Hival_Incl_EP;
4058 -- One further adjustment is needed. In the case of subtypes, we
4059 -- cannot go outside the range of the base type, or we get
4060 -- peculiarities, and the base type range is already set. This
4061 -- only applies to the Incl values, since clearly the Excl values
4062 -- are already as restricted as they are allowed to be.
4065 Loval_Incl_EP := UR_Max (Loval_Incl_EP, Realval (BLo));
4066 Hival_Incl_EP := UR_Min (Hival_Incl_EP, Realval (BHi));
4069 -- Get size including and excluding end points
4071 Size_Incl_EP := Fsize (Loval_Incl_EP, Hival_Incl_EP);
4072 Size_Excl_EP := Fsize (Loval_Excl_EP, Hival_Excl_EP);
4074 -- No need to exclude end-points if it does not reduce size
4076 if Fsize (Loval_Incl_EP, Hival_Excl_EP) = Size_Excl_EP then
4077 Loval_Excl_EP := Loval_Incl_EP;
4080 if Fsize (Loval_Excl_EP, Hival_Incl_EP) = Size_Excl_EP then
4081 Hival_Excl_EP := Hival_Incl_EP;
4084 -- Now we set the actual size to be used. We want to use the
4085 -- bounds fudged up to include the end-points but only if this
4086 -- can be done without violating a specifically given size
4087 -- size clause or causing an unacceptable increase in size.
4089 -- Case of size clause given
4091 if Has_Size_Clause (Typ) then
4093 -- Use the inclusive size only if it is consistent with
4094 -- the explicitly specified size.
4096 if Size_Incl_EP <= RM_Size (Typ) then
4097 Actual_Lo := Loval_Incl_EP;
4098 Actual_Hi := Hival_Incl_EP;
4099 Actual_Size := Size_Incl_EP;
4101 -- If the inclusive size is too large, we try excluding
4102 -- the end-points (will be caught later if does not work).
4105 Actual_Lo := Loval_Excl_EP;
4106 Actual_Hi := Hival_Excl_EP;
4107 Actual_Size := Size_Excl_EP;
4110 -- Case of size clause not given
4113 -- If we have a base type whose corresponding first subtype
4114 -- has an explicit size that is large enough to include our
4115 -- end-points, then do so. There is no point in working hard
4116 -- to get a base type whose size is smaller than the specified
4117 -- size of the first subtype.
4119 First_Subt := First_Subtype (Typ);
4121 if Has_Size_Clause (First_Subt)
4122 and then Size_Incl_EP <= Esize (First_Subt)
4124 Actual_Size := Size_Incl_EP;
4125 Actual_Lo := Loval_Incl_EP;
4126 Actual_Hi := Hival_Incl_EP;
4128 -- If excluding the end-points makes the size smaller and
4129 -- results in a size of 8,16,32,64, then we take the smaller
4130 -- size. For the 64 case, this is compulsory. For the other
4131 -- cases, it seems reasonable. We like to include end points
4132 -- if we can, but not at the expense of moving to the next
4133 -- natural boundary of size.
4135 elsif Size_Incl_EP /= Size_Excl_EP
4137 (Size_Excl_EP = 8 or else
4138 Size_Excl_EP = 16 or else
4139 Size_Excl_EP = 32 or else
4142 Actual_Size := Size_Excl_EP;
4143 Actual_Lo := Loval_Excl_EP;
4144 Actual_Hi := Hival_Excl_EP;
4146 -- Otherwise we can definitely include the end points
4149 Actual_Size := Size_Incl_EP;
4150 Actual_Lo := Loval_Incl_EP;
4151 Actual_Hi := Hival_Incl_EP;
4154 -- One pathological case: normally we never fudge a low bound
4155 -- down, since it would seem to increase the size (if it has
4156 -- any effect), but for ranges containing single value, or no
4157 -- values, the high bound can be small too large. Consider:
4159 -- type t is delta 2.0**(-14)
4160 -- range 131072.0 .. 0;
4162 -- That lower bound is *just* outside the range of 32 bits, and
4163 -- does need fudging down in this case. Note that the bounds
4164 -- will always have crossed here, since the high bound will be
4165 -- fudged down if necessary, as in the case of:
4167 -- type t is delta 2.0**(-14)
4168 -- range 131072.0 .. 131072.0;
4170 -- So we detect the situation by looking for crossed bounds,
4171 -- and if the bounds are crossed, and the low bound is greater
4172 -- than zero, we will always back it off by small, since this
4173 -- is completely harmless.
4175 if Actual_Lo > Actual_Hi then
4176 if UR_Is_Positive (Actual_Lo) then
4177 Actual_Lo := Loval_Incl_EP - Small;
4178 Actual_Size := Fsize (Actual_Lo, Actual_Hi);
4180 -- And of course, we need to do exactly the same parallel
4181 -- fudge for flat ranges in the negative region.
4183 elsif UR_Is_Negative (Actual_Hi) then
4184 Actual_Hi := Hival_Incl_EP + Small;
4185 Actual_Size := Fsize (Actual_Lo, Actual_Hi);
4190 Set_Realval (Lo, Actual_Lo);
4191 Set_Realval (Hi, Actual_Hi);
4194 -- For the decimal case, none of this fudging is required, since there
4195 -- are no end-point problems in the decimal case (the end-points are
4196 -- always included).
4199 Actual_Size := Fsize (Loval, Hival);
4202 -- At this stage, the actual size has been calculated and the proper
4203 -- required bounds are stored in the low and high bounds.
4205 if Actual_Size > 64 then
4206 Error_Msg_Uint_1 := UI_From_Int (Actual_Size);
4208 ("size required (^) for type& too large, maximum is 64", Typ);
4212 -- Check size against explicit given size
4214 if Has_Size_Clause (Typ) then
4215 if Actual_Size > RM_Size (Typ) then
4216 Error_Msg_Uint_1 := RM_Size (Typ);
4217 Error_Msg_Uint_2 := UI_From_Int (Actual_Size);
4219 ("size given (^) for type& too small, minimum is ^",
4220 Size_Clause (Typ), Typ);
4223 Actual_Size := UI_To_Int (Esize (Typ));
4226 -- Increase size to next natural boundary if no size clause given
4229 if Actual_Size <= 8 then
4231 elsif Actual_Size <= 16 then
4233 elsif Actual_Size <= 32 then
4239 Init_Esize (Typ, Actual_Size);
4240 Adjust_Esize_For_Alignment (Typ);
4243 -- If we have a base type, then expand the bounds so that they extend to
4244 -- the full width of the allocated size in bits, to avoid junk range
4245 -- checks on intermediate computations.
4247 if Base_Type (Typ) = Typ then
4248 Set_Realval (Lo, -(Small * (Uint_2 ** (Actual_Size - 1))));
4249 Set_Realval (Hi, (Small * (Uint_2 ** (Actual_Size - 1) - 1)));
4252 -- Final step is to reanalyze the bounds using the proper type
4253 -- and set the Corresponding_Integer_Value fields of the literals.
4255 Set_Etype (Lo, Empty);
4256 Set_Analyzed (Lo, False);
4259 -- Resolve with universal fixed if the base type, and the base type if
4260 -- it is a subtype. Note we can't resolve the base type with itself,
4261 -- that would be a reference before definition.
4264 Resolve (Lo, Universal_Fixed);
4269 -- Set corresponding integer value for bound
4271 Set_Corresponding_Integer_Value
4272 (Lo, UR_To_Uint (Realval (Lo) / Small));
4274 -- Similar processing for high bound
4276 Set_Etype (Hi, Empty);
4277 Set_Analyzed (Hi, False);
4281 Resolve (Hi, Universal_Fixed);
4286 Set_Corresponding_Integer_Value
4287 (Hi, UR_To_Uint (Realval (Hi) / Small));
4289 -- Set type of range to correspond to bounds
4291 Set_Etype (Rng, Etype (Lo));
4293 -- Set Esize to calculated size if not set already
4295 if Unknown_Esize (Typ) then
4296 Init_Esize (Typ, Actual_Size);
4299 -- Set RM_Size if not already set. If already set, check value
4302 Minsiz : constant Uint := UI_From_Int (Minimum_Size (Typ));
4305 if RM_Size (Typ) /= Uint_0 then
4306 if RM_Size (Typ) < Minsiz then
4307 Error_Msg_Uint_1 := RM_Size (Typ);
4308 Error_Msg_Uint_2 := Minsiz;
4310 ("size given (^) for type& too small, minimum is ^",
4311 Size_Clause (Typ), Typ);
4315 Set_RM_Size (Typ, Minsiz);
4318 end Freeze_Fixed_Point_Type;
4324 procedure Freeze_Itype (T : Entity_Id; N : Node_Id) is
4328 Set_Has_Delayed_Freeze (T);
4329 L := Freeze_Entity (T, Sloc (N));
4331 if Is_Non_Empty_List (L) then
4332 Insert_Actions (N, L);
4336 --------------------------
4337 -- Freeze_Static_Object --
4338 --------------------------
4340 procedure Freeze_Static_Object (E : Entity_Id) is
4342 Cannot_Be_Static : exception;
4343 -- Exception raised if the type of a static object cannot be made
4344 -- static. This happens if the type depends on non-global objects.
4346 procedure Ensure_Expression_Is_SA (N : Node_Id);
4347 -- Called to ensure that an expression used as part of a type definition
4348 -- is statically allocatable, which means that the expression type is
4349 -- statically allocatable, and the expression is either static, or a
4350 -- reference to a library level constant.
4352 procedure Ensure_Type_Is_SA (Typ : Entity_Id);
4353 -- Called to mark a type as static, checking that it is possible
4354 -- to set the type as static. If it is not possible, then the
4355 -- exception Cannot_Be_Static is raised.
4357 -----------------------------
4358 -- Ensure_Expression_Is_SA --
4359 -----------------------------
4361 procedure Ensure_Expression_Is_SA (N : Node_Id) is
4365 Ensure_Type_Is_SA (Etype (N));
4367 if Is_Static_Expression (N) then
4370 elsif Nkind (N) = N_Identifier then
4374 and then Ekind (Ent) = E_Constant
4375 and then Is_Library_Level_Entity (Ent)
4381 raise Cannot_Be_Static;
4382 end Ensure_Expression_Is_SA;
4384 -----------------------
4385 -- Ensure_Type_Is_SA --
4386 -----------------------
4388 procedure Ensure_Type_Is_SA (Typ : Entity_Id) is
4393 -- If type is library level, we are all set
4395 if Is_Library_Level_Entity (Typ) then
4399 -- We are also OK if the type already marked as statically allocated,
4400 -- which means we processed it before.
4402 if Is_Statically_Allocated (Typ) then
4406 -- Mark type as statically allocated
4408 Set_Is_Statically_Allocated (Typ);
4410 -- Check that it is safe to statically allocate this type
4412 if Is_Scalar_Type (Typ) or else Is_Real_Type (Typ) then
4413 Ensure_Expression_Is_SA (Type_Low_Bound (Typ));
4414 Ensure_Expression_Is_SA (Type_High_Bound (Typ));
4416 elsif Is_Array_Type (Typ) then
4417 N := First_Index (Typ);
4418 while Present (N) loop
4419 Ensure_Type_Is_SA (Etype (N));
4423 Ensure_Type_Is_SA (Component_Type (Typ));
4425 elsif Is_Access_Type (Typ) then
4426 if Ekind (Designated_Type (Typ)) = E_Subprogram_Type then
4430 T : constant Entity_Id := Etype (Designated_Type (Typ));
4433 if T /= Standard_Void_Type then
4434 Ensure_Type_Is_SA (T);
4437 F := First_Formal (Designated_Type (Typ));
4439 while Present (F) loop
4440 Ensure_Type_Is_SA (Etype (F));
4446 Ensure_Type_Is_SA (Designated_Type (Typ));
4449 elsif Is_Record_Type (Typ) then
4450 C := First_Entity (Typ);
4452 while Present (C) loop
4453 if Ekind (C) = E_Discriminant
4454 or else Ekind (C) = E_Component
4456 Ensure_Type_Is_SA (Etype (C));
4458 elsif Is_Type (C) then
4459 Ensure_Type_Is_SA (C);
4465 elsif Ekind (Typ) = E_Subprogram_Type then
4466 Ensure_Type_Is_SA (Etype (Typ));
4468 C := First_Formal (Typ);
4469 while Present (C) loop
4470 Ensure_Type_Is_SA (Etype (C));
4475 raise Cannot_Be_Static;
4477 end Ensure_Type_Is_SA;
4479 -- Start of processing for Freeze_Static_Object
4482 Ensure_Type_Is_SA (Etype (E));
4484 -- Reset True_Constant flag, since something strange is going on with
4485 -- the scoping here, and our simple value tracing may not be sufficient
4486 -- for this indication to be reliable. We kill the Constant_Value
4487 -- indication for the same reason.
4489 Set_Is_True_Constant (E, False);
4490 Set_Current_Value (E, Empty);
4493 when Cannot_Be_Static =>
4495 -- If the object that cannot be static is imported or exported,
4496 -- then we give an error message saying that this object cannot
4497 -- be imported or exported.
4499 if Is_Imported (E) then
4501 ("& cannot be imported (local type is not constant)", E);
4503 -- Otherwise must be exported, something is wrong if compiler
4504 -- is marking something as statically allocated which cannot be).
4506 else pragma Assert (Is_Exported (E));
4508 ("& cannot be exported (local type is not constant)", E);
4510 end Freeze_Static_Object;
4512 -----------------------
4513 -- Freeze_Subprogram --
4514 -----------------------
4516 procedure Freeze_Subprogram (E : Entity_Id) is
4521 -- Subprogram may not have an address clause unless it is imported
4523 if Present (Address_Clause (E)) then
4524 if not Is_Imported (E) then
4526 ("address clause can only be given " &
4527 "for imported subprogram",
4528 Name (Address_Clause (E)));
4532 -- Reset the Pure indication on an imported subprogram unless an
4533 -- explicit Pure_Function pragma was present. We do this because
4534 -- otherwise it is an insidious error to call a non-pure function from
4535 -- pure unit and have calls mysteriously optimized away. What happens
4536 -- here is that the Import can bypass the normal check to ensure that
4537 -- pure units call only pure subprograms.
4540 and then Is_Pure (E)
4541 and then not Has_Pragma_Pure_Function (E)
4543 Set_Is_Pure (E, False);
4546 -- For non-foreign convention subprograms, this is where we create
4547 -- the extra formals (for accessibility level and constrained bit
4548 -- information). We delay this till the freeze point precisely so
4549 -- that we know the convention!
4551 if not Has_Foreign_Convention (E) then
4552 Create_Extra_Formals (E);
4555 -- If this is convention Ada and a Valued_Procedure, that's odd
4557 if Ekind (E) = E_Procedure
4558 and then Is_Valued_Procedure (E)
4559 and then Convention (E) = Convention_Ada
4560 and then Warn_On_Export_Import
4563 ("?Valued_Procedure has no effect for convention Ada", E);
4564 Set_Is_Valued_Procedure (E, False);
4567 -- Case of foreign convention
4572 -- For foreign conventions, warn about return of an
4573 -- unconstrained array.
4575 -- Note: we *do* allow a return by descriptor for the VMS case,
4576 -- though here there is probably more to be done ???
4578 if Ekind (E) = E_Function then
4579 Retype := Underlying_Type (Etype (E));
4581 -- If no return type, probably some other error, e.g. a
4582 -- missing full declaration, so ignore.
4587 -- If the return type is generic, we have emitted a warning
4588 -- earlier on, and there is nothing else to check here. Specific
4589 -- instantiations may lead to erroneous behavior.
4591 elsif Is_Generic_Type (Etype (E)) then
4594 elsif Is_Array_Type (Retype)
4595 and then not Is_Constrained (Retype)
4596 and then Mechanism (E) not in Descriptor_Codes
4597 and then Warn_On_Export_Import
4600 ("?foreign convention function& should not return " &
4601 "unconstrained array", E);
4606 -- If any of the formals for an exported foreign convention
4607 -- subprogram have defaults, then emit an appropriate warning since
4608 -- this is odd (default cannot be used from non-Ada code)
4610 if Is_Exported (E) then
4611 F := First_Formal (E);
4612 while Present (F) loop
4613 if Warn_On_Export_Import
4614 and then Present (Default_Value (F))
4617 ("?parameter cannot be defaulted in non-Ada call",
4626 -- For VMS, descriptor mechanisms for parameters are allowed only
4627 -- for imported subprograms.
4629 if OpenVMS_On_Target then
4630 if not Is_Imported (E) then
4631 F := First_Formal (E);
4632 while Present (F) loop
4633 if Mechanism (F) in Descriptor_Codes then
4635 ("descriptor mechanism for parameter not permitted", F);
4637 ("\can only be used for imported subprogram", F);
4645 -- Pragma Inline_Always is disallowed for dispatching subprograms
4646 -- because the address of such subprograms is saved in the dispatch
4647 -- table to support dispatching calls, and dispatching calls cannot
4648 -- be inlined. This is consistent with the restriction against using
4649 -- 'Access or 'Address on an Inline_Always subprogram.
4651 if Is_Dispatching_Operation (E) and then Is_Always_Inlined (E) then
4653 ("pragma Inline_Always not allowed for dispatching subprograms", E);
4655 end Freeze_Subprogram;
4657 ----------------------
4658 -- Is_Fully_Defined --
4659 ----------------------
4661 function Is_Fully_Defined (T : Entity_Id) return Boolean is
4663 if Ekind (T) = E_Class_Wide_Type then
4664 return Is_Fully_Defined (Etype (T));
4666 elsif Is_Array_Type (T) then
4667 return Is_Fully_Defined (Component_Type (T));
4669 elsif Is_Record_Type (T)
4670 and not Is_Private_Type (T)
4672 -- Verify that the record type has no components with private types
4673 -- without completion.
4679 Comp := First_Component (T);
4681 while Present (Comp) loop
4682 if not Is_Fully_Defined (Etype (Comp)) then
4686 Next_Component (Comp);
4691 else return not Is_Private_Type (T)
4692 or else Present (Full_View (Base_Type (T)));
4694 end Is_Fully_Defined;
4696 ---------------------------------
4697 -- Process_Default_Expressions --
4698 ---------------------------------
4700 procedure Process_Default_Expressions
4702 After : in out Node_Id)
4704 Loc : constant Source_Ptr := Sloc (E);
4711 Set_Default_Expressions_Processed (E);
4713 -- A subprogram instance and its associated anonymous subprogram share
4714 -- their signature. The default expression functions are defined in the
4715 -- wrapper packages for the anonymous subprogram, and should not be
4716 -- generated again for the instance.
4718 if Is_Generic_Instance (E)
4719 and then Present (Alias (E))
4720 and then Default_Expressions_Processed (Alias (E))
4725 Formal := First_Formal (E);
4727 while Present (Formal) loop
4728 if Present (Default_Value (Formal)) then
4730 -- We work with a copy of the default expression because we
4731 -- do not want to disturb the original, since this would mess
4732 -- up the conformance checking.
4734 Dcopy := New_Copy_Tree (Default_Value (Formal));
4736 -- The analysis of the expression may generate insert actions,
4737 -- which of course must not be executed. We wrap those actions
4738 -- in a procedure that is not called, and later on eliminated.
4739 -- The following cases have no side-effects, and are analyzed
4742 if Nkind (Dcopy) = N_Identifier
4743 or else Nkind (Dcopy) = N_Expanded_Name
4744 or else Nkind (Dcopy) = N_Integer_Literal
4745 or else (Nkind (Dcopy) = N_Real_Literal
4746 and then not Vax_Float (Etype (Dcopy)))
4747 or else Nkind (Dcopy) = N_Character_Literal
4748 or else Nkind (Dcopy) = N_String_Literal
4749 or else Nkind (Dcopy) = N_Null
4750 or else (Nkind (Dcopy) = N_Attribute_Reference
4752 Attribute_Name (Dcopy) = Name_Null_Parameter)
4755 -- If there is no default function, we must still do a full
4756 -- analyze call on the default value, to ensure that all error
4757 -- checks are performed, e.g. those associated with static
4758 -- evaluation. Note: this branch will always be taken if the
4759 -- analyzer is turned off (but we still need the error checks).
4761 -- Note: the setting of parent here is to meet the requirement
4762 -- that we can only analyze the expression while attached to
4763 -- the tree. Really the requirement is that the parent chain
4764 -- be set, we don't actually need to be in the tree.
4766 Set_Parent (Dcopy, Declaration_Node (Formal));
4769 -- Default expressions are resolved with their own type if the
4770 -- context is generic, to avoid anomalies with private types.
4772 if Ekind (Scope (E)) = E_Generic_Package then
4775 Resolve (Dcopy, Etype (Formal));
4778 -- If that resolved expression will raise constraint error,
4779 -- then flag the default value as raising constraint error.
4780 -- This allows a proper error message on the calls.
4782 if Raises_Constraint_Error (Dcopy) then
4783 Set_Raises_Constraint_Error (Default_Value (Formal));
4786 -- If the default is a parameterless call, we use the name of
4787 -- the called function directly, and there is no body to build.
4789 elsif Nkind (Dcopy) = N_Function_Call
4790 and then No (Parameter_Associations (Dcopy))
4794 -- Else construct and analyze the body of a wrapper procedure
4795 -- that contains an object declaration to hold the expression.
4796 -- Given that this is done only to complete the analysis, it
4797 -- simpler to build a procedure than a function which might
4798 -- involve secondary stack expansion.
4802 Make_Defining_Identifier (Loc, New_Internal_Name ('D'));
4805 Make_Subprogram_Body (Loc,
4807 Make_Procedure_Specification (Loc,
4808 Defining_Unit_Name => Dnam),
4810 Declarations => New_List (
4811 Make_Object_Declaration (Loc,
4812 Defining_Identifier =>
4813 Make_Defining_Identifier (Loc,
4814 New_Internal_Name ('T')),
4815 Object_Definition =>
4816 New_Occurrence_Of (Etype (Formal), Loc),
4817 Expression => New_Copy_Tree (Dcopy))),
4819 Handled_Statement_Sequence =>
4820 Make_Handled_Sequence_Of_Statements (Loc,
4821 Statements => New_List));
4823 Set_Scope (Dnam, Scope (E));
4824 Set_Assignment_OK (First (Declarations (Dbody)));
4825 Set_Is_Eliminated (Dnam);
4826 Insert_After (After, Dbody);
4832 Next_Formal (Formal);
4835 end Process_Default_Expressions;
4837 ----------------------------------------
4838 -- Set_Component_Alignment_If_Not_Set --
4839 ----------------------------------------
4841 procedure Set_Component_Alignment_If_Not_Set (Typ : Entity_Id) is
4843 -- Ignore if not base type, subtypes don't need anything
4845 if Typ /= Base_Type (Typ) then
4849 -- Do not override existing representation
4851 if Is_Packed (Typ) then
4854 elsif Has_Specified_Layout (Typ) then
4857 elsif Component_Alignment (Typ) /= Calign_Default then
4861 Set_Component_Alignment
4862 (Typ, Scope_Stack.Table
4863 (Scope_Stack.Last).Component_Alignment_Default);
4865 end Set_Component_Alignment_If_Not_Set;
4867 ---------------------------
4868 -- Set_Debug_Info_Needed --
4869 ---------------------------
4871 procedure Set_Debug_Info_Needed (T : Entity_Id) is
4874 or else Needs_Debug_Info (T)
4875 or else Debug_Info_Off (T)
4879 Set_Needs_Debug_Info (T);
4882 if Is_Object (T) then
4883 Set_Debug_Info_Needed (Etype (T));
4885 elsif Is_Type (T) then
4886 Set_Debug_Info_Needed (Etype (T));
4888 if Is_Record_Type (T) then
4890 Ent : Entity_Id := First_Entity (T);
4892 while Present (Ent) loop
4893 Set_Debug_Info_Needed (Ent);
4898 elsif Is_Array_Type (T) then
4899 Set_Debug_Info_Needed (Component_Type (T));
4902 Indx : Node_Id := First_Index (T);
4904 while Present (Indx) loop
4905 Set_Debug_Info_Needed (Etype (Indx));
4906 Indx := Next_Index (Indx);
4910 if Is_Packed (T) then
4911 Set_Debug_Info_Needed (Packed_Array_Type (T));
4914 elsif Is_Access_Type (T) then
4915 Set_Debug_Info_Needed (Directly_Designated_Type (T));
4917 elsif Is_Private_Type (T) then
4918 Set_Debug_Info_Needed (Full_View (T));
4920 elsif Is_Protected_Type (T) then
4921 Set_Debug_Info_Needed (Corresponding_Record_Type (T));
4924 end Set_Debug_Info_Needed;
4930 procedure Undelay_Type (T : Entity_Id) is
4932 Set_Has_Delayed_Freeze (T, False);
4933 Set_Freeze_Node (T, Empty);
4935 -- Since we don't want T to have a Freeze_Node, we don't want its
4936 -- Full_View or Corresponding_Record_Type to have one either.
4938 -- ??? Fundamentally, this whole handling is a kludge. What we really
4939 -- want is to be sure that for an Itype that's part of record R and is a
4940 -- subtype of type T, that it's frozen after the later of the freeze
4941 -- points of R and T. We have no way of doing that directly, so what we
4942 -- do is force most such Itypes to be frozen as part of freezing R via
4943 -- this procedure and only delay the ones that need to be delayed
4944 -- (mostly the designated types of access types that are defined as part
4947 if Is_Private_Type (T)
4948 and then Present (Full_View (T))
4949 and then Is_Itype (Full_View (T))
4950 and then Is_Record_Type (Scope (Full_View (T)))
4952 Undelay_Type (Full_View (T));
4955 if Is_Concurrent_Type (T)
4956 and then Present (Corresponding_Record_Type (T))
4957 and then Is_Itype (Corresponding_Record_Type (T))
4958 and then Is_Record_Type (Scope (Corresponding_Record_Type (T)))
4960 Undelay_Type (Corresponding_Record_Type (T));
4968 procedure Warn_Overlay
4973 Ent : constant Entity_Id := Entity (Nam);
4974 -- The object to which the address clause applies
4977 Old : Entity_Id := Empty;
4981 -- No warning if address clause overlay warnings are off
4983 if not Address_Clause_Overlay_Warnings then
4987 -- No warning if there is an explicit initialization
4989 Init := Original_Node (Expression (Declaration_Node (Ent)));
4991 if Present (Init) and then Comes_From_Source (Init) then
4995 -- We only give the warning for non-imported entities of a type for
4996 -- which a non-null base init proc is defined (or for access types which
4997 -- have implicit null initialization).
5000 and then (Has_Non_Null_Base_Init_Proc (Typ)
5001 or else Is_Access_Type (Typ))
5002 and then not Is_Imported (Ent)
5004 if Nkind (Expr) = N_Attribute_Reference
5005 and then Is_Entity_Name (Prefix (Expr))
5007 Old := Entity (Prefix (Expr));
5009 elsif Is_Entity_Name (Expr)
5010 and then Ekind (Entity (Expr)) = E_Constant
5012 Decl := Declaration_Node (Entity (Expr));
5014 if Nkind (Decl) = N_Object_Declaration
5015 and then Present (Expression (Decl))
5016 and then Nkind (Expression (Decl)) = N_Attribute_Reference
5017 and then Is_Entity_Name (Prefix (Expression (Decl)))
5019 Old := Entity (Prefix (Expression (Decl)));
5021 elsif Nkind (Expr) = N_Function_Call then
5025 -- A function call (most likely to To_Address) is probably not an
5026 -- overlay, so skip warning. Ditto if the function call was inlined
5027 -- and transformed into an entity.
5029 elsif Nkind (Original_Node (Expr)) = N_Function_Call then
5033 Decl := Next (Parent (Expr));
5035 -- If a pragma Import follows, we assume that it is for the current
5036 -- target of the address clause, and skip the warning.
5039 and then Nkind (Decl) = N_Pragma
5040 and then Chars (Decl) = Name_Import
5045 if Present (Old) then
5046 Error_Msg_Node_2 := Old;
5048 ("default initialization of & may modify &?",
5052 ("default initialization of & may modify overlaid storage?",
5056 -- Add friendly warning if initialization comes from a packed array
5059 if Is_Record_Type (Typ) then
5064 Comp := First_Component (Typ);
5066 while Present (Comp) loop
5067 if Nkind (Parent (Comp)) = N_Component_Declaration
5068 and then Present (Expression (Parent (Comp)))
5071 elsif Is_Array_Type (Etype (Comp))
5072 and then Present (Packed_Array_Type (Etype (Comp)))
5075 ("packed array component& will be initialized to zero?",
5079 Next_Component (Comp);
5086 ("use pragma Import for & to " &
5087 "suppress initialization ('R'M B.1(24))?",
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