1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2009, 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 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. --
18 -- You should have received a copy of the GNU General Public License along --
19 -- with this program; see file COPYING3. If not see --
20 -- <http://www.gnu.org/licenses/>. --
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_Ch3; use Exp_Ch3;
33 with Exp_Ch7; use Exp_Ch7;
34 with Exp_Disp; use Exp_Disp;
35 with Exp_Pakd; use Exp_Pakd;
36 with Exp_Util; use Exp_Util;
37 with Exp_Tss; use Exp_Tss;
38 with Layout; use Layout;
39 with Namet; use Namet;
40 with Nlists; use Nlists;
41 with Nmake; use Nmake;
43 with Restrict; use Restrict;
44 with Rident; use Rident;
46 with Sem_Aux; use Sem_Aux;
47 with Sem_Cat; use Sem_Cat;
48 with Sem_Ch6; use Sem_Ch6;
49 with Sem_Ch7; use Sem_Ch7;
50 with Sem_Ch8; use Sem_Ch8;
51 with Sem_Ch13; use Sem_Ch13;
52 with Sem_Eval; use Sem_Eval;
53 with Sem_Mech; use Sem_Mech;
54 with Sem_Prag; use Sem_Prag;
55 with Sem_Res; use Sem_Res;
56 with Sem_Util; use Sem_Util;
57 with Sinfo; use Sinfo;
58 with Snames; use Snames;
59 with Stand; use Stand;
60 with Targparm; use Targparm;
61 with Tbuild; use Tbuild;
62 with Ttypes; use Ttypes;
63 with Uintp; use Uintp;
64 with Urealp; use Urealp;
66 package body Freeze is
68 -----------------------
69 -- Local Subprograms --
70 -----------------------
72 procedure Adjust_Esize_For_Alignment (Typ : Entity_Id);
73 -- Typ is a type that is being frozen. If no size clause is given,
74 -- but a default Esize has been computed, then this default Esize is
75 -- adjusted up if necessary to be consistent with a given alignment,
76 -- but never to a value greater than Long_Long_Integer'Size. This
77 -- is used for all discrete types and for fixed-point types.
79 procedure Build_And_Analyze_Renamed_Body
82 After : in out Node_Id);
83 -- Build body for a renaming declaration, insert in tree and analyze
85 procedure Check_Address_Clause (E : Entity_Id);
86 -- Apply legality checks to address clauses for object declarations,
87 -- at the point the object is frozen.
89 procedure Check_Strict_Alignment (E : Entity_Id);
90 -- E is a base type. If E is tagged or has a component that is aliased
91 -- or tagged or contains something this is aliased or tagged, set
94 procedure Check_Unsigned_Type (E : Entity_Id);
95 pragma Inline (Check_Unsigned_Type);
96 -- If E is a fixed-point or discrete type, then all the necessary work
97 -- to freeze it is completed except for possible setting of the flag
98 -- Is_Unsigned_Type, which is done by this procedure. The call has no
99 -- effect if the entity E is not a discrete or fixed-point type.
101 procedure Freeze_And_Append
104 Result : in out List_Id);
105 -- Freezes Ent using Freeze_Entity, and appends the resulting list of
106 -- nodes to Result, modifying Result from No_List if necessary.
108 procedure Freeze_Enumeration_Type (Typ : Entity_Id);
109 -- Freeze enumeration type. The Esize field is set as processing
110 -- proceeds (i.e. set by default when the type is declared and then
111 -- adjusted by rep clauses. What this procedure does is to make sure
112 -- that if a foreign convention is specified, and no specific size
113 -- is given, then the size must be at least Integer'Size.
115 procedure Freeze_Static_Object (E : Entity_Id);
116 -- If an object is frozen which has Is_Statically_Allocated set, then
117 -- all referenced types must also be marked with this flag. This routine
118 -- is in charge of meeting this requirement for the object entity E.
120 procedure Freeze_Subprogram (E : Entity_Id);
121 -- Perform freezing actions for a subprogram (create extra formals,
122 -- and set proper default mechanism values). Note that this routine
123 -- is not called for internal subprograms, for which neither of these
124 -- actions is needed (or desirable, we do not want for example to have
125 -- these extra formals present in initialization procedures, where they
126 -- would serve no purpose). In this call E is either a subprogram or
127 -- a subprogram type (i.e. an access to a subprogram).
129 function Is_Fully_Defined (T : Entity_Id) return Boolean;
130 -- True if T is not private and has no private components, or has a full
131 -- view. Used to determine whether the designated type of an access type
132 -- should be frozen when the access type is frozen. This is done when an
133 -- allocator is frozen, or an expression that may involve attributes of
134 -- the designated type. Otherwise freezing the access type does not freeze
135 -- the designated type.
137 procedure Process_Default_Expressions
139 After : in out Node_Id);
140 -- This procedure is called for each subprogram to complete processing
141 -- of default expressions at the point where all types are known to be
142 -- frozen. The expressions must be analyzed in full, to make sure that
143 -- all error processing is done (they have only been pre-analyzed). If
144 -- the expression is not an entity or literal, its analysis may generate
145 -- code which must not be executed. In that case we build a function
146 -- body to hold that code. This wrapper function serves no other purpose
147 -- (it used to be called to evaluate the default, but now the default is
148 -- inlined at each point of call).
150 procedure Set_Component_Alignment_If_Not_Set (Typ : Entity_Id);
151 -- Typ is a record or array type that is being frozen. This routine
152 -- sets the default component alignment from the scope stack values
153 -- if the alignment is otherwise not specified.
155 procedure Check_Debug_Info_Needed (T : Entity_Id);
156 -- As each entity is frozen, this routine is called to deal with the
157 -- setting of Debug_Info_Needed for the entity. This flag is set if
158 -- the entity comes from source, or if we are in Debug_Generated_Code
159 -- mode or if the -gnatdV debug flag is set. However, it never sets
160 -- the flag if Debug_Info_Off is set. This procedure also ensures that
161 -- subsidiary entities have the flag set as required.
163 procedure Undelay_Type (T : Entity_Id);
164 -- T is a type of a component that we know to be an Itype.
165 -- We don't want this to have a Freeze_Node, so ensure it doesn't.
166 -- Do the same for any Full_View or Corresponding_Record_Type.
168 procedure Warn_Overlay
172 -- Expr is the expression for an address clause for entity Nam whose type
173 -- is Typ. If Typ has a default initialization, and there is no explicit
174 -- initialization in the source declaration, check whether the address
175 -- clause might cause overlaying of an entity, and emit a warning on the
176 -- side effect that the initialization will cause.
178 -------------------------------
179 -- Adjust_Esize_For_Alignment --
180 -------------------------------
182 procedure Adjust_Esize_For_Alignment (Typ : Entity_Id) is
186 if Known_Esize (Typ) and then Known_Alignment (Typ) then
187 Align := Alignment_In_Bits (Typ);
189 if Align > Esize (Typ)
190 and then Align <= Standard_Long_Long_Integer_Size
192 Set_Esize (Typ, Align);
195 end Adjust_Esize_For_Alignment;
197 ------------------------------------
198 -- Build_And_Analyze_Renamed_Body --
199 ------------------------------------
201 procedure Build_And_Analyze_Renamed_Body
204 After : in out Node_Id)
206 Body_Node : constant Node_Id := Build_Renamed_Body (Decl, New_S);
208 Insert_After (After, Body_Node);
209 Mark_Rewrite_Insertion (Body_Node);
212 end Build_And_Analyze_Renamed_Body;
214 ------------------------
215 -- Build_Renamed_Body --
216 ------------------------
218 function Build_Renamed_Body
220 New_S : Entity_Id) return Node_Id
222 Loc : constant Source_Ptr := Sloc (New_S);
223 -- We use for the source location of the renamed body, the location
224 -- of the spec entity. It might seem more natural to use the location
225 -- of the renaming declaration itself, but that would be wrong, since
226 -- then the body we create would look as though it was created far
227 -- too late, and this could cause problems with elaboration order
228 -- analysis, particularly in connection with instantiations.
230 N : constant Node_Id := Unit_Declaration_Node (New_S);
231 Nam : constant Node_Id := Name (N);
233 Spec : constant Node_Id := New_Copy_Tree (Specification (Decl));
234 Actuals : List_Id := No_List;
239 O_Formal : Entity_Id;
240 Param_Spec : Node_Id;
242 Pref : Node_Id := Empty;
243 -- If the renamed entity is a primitive operation given in prefix form,
244 -- the prefix is the target object and it has to be added as the first
245 -- actual in the generated call.
248 -- Determine the entity being renamed, which is the target of the call
249 -- statement. If the name is an explicit dereference, this is a renaming
250 -- of a subprogram type rather than a subprogram. The name itself is
253 if Nkind (Nam) = N_Selected_Component then
254 Old_S := Entity (Selector_Name (Nam));
256 elsif Nkind (Nam) = N_Explicit_Dereference then
257 Old_S := Etype (Nam);
259 elsif Nkind (Nam) = N_Indexed_Component then
260 if Is_Entity_Name (Prefix (Nam)) then
261 Old_S := Entity (Prefix (Nam));
263 Old_S := Entity (Selector_Name (Prefix (Nam)));
266 elsif Nkind (Nam) = N_Character_Literal then
267 Old_S := Etype (New_S);
270 Old_S := Entity (Nam);
273 if Is_Entity_Name (Nam) then
275 -- If the renamed entity is a predefined operator, retain full name
276 -- to ensure its visibility.
278 if Ekind (Old_S) = E_Operator
279 and then Nkind (Nam) = N_Expanded_Name
281 Call_Name := New_Copy (Name (N));
283 Call_Name := New_Reference_To (Old_S, Loc);
287 if Nkind (Nam) = N_Selected_Component
288 and then Present (First_Formal (Old_S))
290 (Is_Controlling_Formal (First_Formal (Old_S))
291 or else Is_Class_Wide_Type (Etype (First_Formal (Old_S))))
294 -- Retrieve the target object, to be added as a first actual
297 Call_Name := New_Occurrence_Of (Old_S, Loc);
298 Pref := Prefix (Nam);
301 Call_Name := New_Copy (Name (N));
304 -- The original name may have been overloaded, but
305 -- is fully resolved now.
307 Set_Is_Overloaded (Call_Name, False);
310 -- For simple renamings, subsequent calls can be expanded directly as
311 -- called to the renamed entity. The body must be generated in any case
312 -- for calls they may appear elsewhere.
314 if (Ekind (Old_S) = E_Function
315 or else Ekind (Old_S) = E_Procedure)
316 and then Nkind (Decl) = N_Subprogram_Declaration
318 Set_Body_To_Inline (Decl, Old_S);
321 -- The body generated for this renaming is an internal artifact, and
322 -- does not constitute a freeze point for the called entity.
324 Set_Must_Not_Freeze (Call_Name);
326 Formal := First_Formal (Defining_Entity (Decl));
328 if Present (Pref) then
330 Pref_Type : constant Entity_Id := Etype (Pref);
331 Form_Type : constant Entity_Id := Etype (First_Formal (Old_S));
335 -- The controlling formal may be an access parameter, or the
336 -- actual may be an access value, so adjust accordingly.
338 if Is_Access_Type (Pref_Type)
339 and then not Is_Access_Type (Form_Type)
342 (Make_Explicit_Dereference (Loc, Relocate_Node (Pref)));
344 elsif Is_Access_Type (Form_Type)
345 and then not Is_Access_Type (Pref)
348 (Make_Attribute_Reference (Loc,
349 Attribute_Name => Name_Access,
350 Prefix => Relocate_Node (Pref)));
352 Actuals := New_List (Pref);
356 elsif Present (Formal) then
363 if Present (Formal) then
364 while Present (Formal) loop
365 Append (New_Reference_To (Formal, Loc), Actuals);
366 Next_Formal (Formal);
370 -- If the renamed entity is an entry, inherit its profile. For other
371 -- renamings as bodies, both profiles must be subtype conformant, so it
372 -- is not necessary to replace the profile given in the declaration.
373 -- However, default values that are aggregates are rewritten when
374 -- partially analyzed, so we recover the original aggregate to insure
375 -- that subsequent conformity checking works. Similarly, if the default
376 -- expression was constant-folded, recover the original expression.
378 Formal := First_Formal (Defining_Entity (Decl));
380 if Present (Formal) then
381 O_Formal := First_Formal (Old_S);
382 Param_Spec := First (Parameter_Specifications (Spec));
384 while Present (Formal) loop
385 if Is_Entry (Old_S) then
387 if Nkind (Parameter_Type (Param_Spec)) /=
390 Set_Etype (Formal, Etype (O_Formal));
391 Set_Entity (Parameter_Type (Param_Spec), Etype (O_Formal));
394 elsif Nkind (Default_Value (O_Formal)) = N_Aggregate
395 or else Nkind (Original_Node (Default_Value (O_Formal))) /=
396 Nkind (Default_Value (O_Formal))
398 Set_Expression (Param_Spec,
399 New_Copy_Tree (Original_Node (Default_Value (O_Formal))));
402 Next_Formal (Formal);
403 Next_Formal (O_Formal);
408 -- If the renamed entity is a function, the generated body contains a
409 -- return statement. Otherwise, build a procedure call. If the entity is
410 -- an entry, subsequent analysis of the call will transform it into the
411 -- proper entry or protected operation call. If the renamed entity is
412 -- a character literal, return it directly.
414 if Ekind (Old_S) = E_Function
415 or else Ekind (Old_S) = E_Operator
416 or else (Ekind (Old_S) = E_Subprogram_Type
417 and then Etype (Old_S) /= Standard_Void_Type)
420 Make_Simple_Return_Statement (Loc,
422 Make_Function_Call (Loc,
424 Parameter_Associations => Actuals));
426 elsif Ekind (Old_S) = E_Enumeration_Literal then
428 Make_Simple_Return_Statement (Loc,
429 Expression => New_Occurrence_Of (Old_S, Loc));
431 elsif Nkind (Nam) = N_Character_Literal then
433 Make_Simple_Return_Statement (Loc,
434 Expression => Call_Name);
438 Make_Procedure_Call_Statement (Loc,
440 Parameter_Associations => Actuals);
443 -- Create entities for subprogram body and formals
445 Set_Defining_Unit_Name (Spec,
446 Make_Defining_Identifier (Loc, Chars => Chars (New_S)));
448 Param_Spec := First (Parameter_Specifications (Spec));
450 while Present (Param_Spec) loop
451 Set_Defining_Identifier (Param_Spec,
452 Make_Defining_Identifier (Loc,
453 Chars => Chars (Defining_Identifier (Param_Spec))));
458 Make_Subprogram_Body (Loc,
459 Specification => Spec,
460 Declarations => New_List,
461 Handled_Statement_Sequence =>
462 Make_Handled_Sequence_Of_Statements (Loc,
463 Statements => New_List (Call_Node)));
465 if Nkind (Decl) /= N_Subprogram_Declaration then
467 Make_Subprogram_Declaration (Loc,
468 Specification => Specification (N)));
471 -- Link the body to the entity whose declaration it completes. If
472 -- the body is analyzed when the renamed entity is frozen, it may
473 -- be necessary to restore the proper scope (see package Exp_Ch13).
475 if Nkind (N) = N_Subprogram_Renaming_Declaration
476 and then Present (Corresponding_Spec (N))
478 Set_Corresponding_Spec (Body_Node, Corresponding_Spec (N));
480 Set_Corresponding_Spec (Body_Node, New_S);
484 end Build_Renamed_Body;
486 --------------------------
487 -- Check_Address_Clause --
488 --------------------------
490 procedure Check_Address_Clause (E : Entity_Id) is
491 Addr : constant Node_Id := Address_Clause (E);
493 Decl : constant Node_Id := Declaration_Node (E);
494 Typ : constant Entity_Id := Etype (E);
497 if Present (Addr) then
498 Expr := Expression (Addr);
500 -- If we have no initialization of any kind, then we don't need to
501 -- place any restrictions on the address clause, because the object
502 -- will be elaborated after the address clause is evaluated. This
503 -- happens if the declaration has no initial expression, or the type
504 -- has no implicit initialization, or the object is imported.
506 -- The same holds for all initialized scalar types and all access
507 -- types. Packed bit arrays of size up to 64 are represented using a
508 -- modular type with an initialization (to zero) and can be processed
509 -- like other initialized scalar types.
511 -- If the type is controlled, code to attach the object to a
512 -- finalization chain is generated at the point of declaration,
513 -- and therefore the elaboration of the object cannot be delayed:
514 -- the address expression must be a constant.
516 if (No (Expression (Decl))
517 and then not Needs_Finalization (Typ)
519 (not Has_Non_Null_Base_Init_Proc (Typ)
520 or else Is_Imported (E)))
523 (Present (Expression (Decl))
524 and then Is_Scalar_Type (Typ))
530 (Is_Bit_Packed_Array (Typ)
532 Is_Modular_Integer_Type (Packed_Array_Type (Typ)))
536 -- Otherwise, we require the address clause to be constant because
537 -- the call to the initialization procedure (or the attach code) has
538 -- to happen at the point of the declaration.
539 -- Actually the IP call has been moved to the freeze actions
540 -- anyway, so maybe we can relax this restriction???
543 Check_Constant_Address_Clause (Expr, E);
545 -- Has_Delayed_Freeze was set on E when the address clause was
546 -- analyzed. Reset the flag now unless freeze actions were
547 -- attached to it in the mean time.
549 if No (Freeze_Node (E)) then
550 Set_Has_Delayed_Freeze (E, False);
554 if not Error_Posted (Expr)
555 and then not Needs_Finalization (Typ)
557 Warn_Overlay (Expr, Typ, Name (Addr));
560 end Check_Address_Clause;
562 -----------------------------
563 -- Check_Compile_Time_Size --
564 -----------------------------
566 procedure Check_Compile_Time_Size (T : Entity_Id) is
568 procedure Set_Small_Size (T : Entity_Id; S : Uint);
569 -- Sets the compile time known size (32 bits or less) in the Esize
570 -- field, of T checking for a size clause that was given which attempts
571 -- to give a smaller size.
573 function Size_Known (T : Entity_Id) return Boolean;
574 -- Recursive function that does all the work
576 function Static_Discriminated_Components (T : Entity_Id) return Boolean;
577 -- If T is a constrained subtype, its size is not known if any of its
578 -- discriminant constraints is not static and it is not a null record.
579 -- The test is conservative and doesn't check that the components are
580 -- in fact constrained by non-static discriminant values. Could be made
587 procedure Set_Small_Size (T : Entity_Id; S : Uint) is
592 elsif Has_Size_Clause (T) then
593 if RM_Size (T) < S then
594 Error_Msg_Uint_1 := S;
596 ("size for & too small, minimum allowed is ^",
599 elsif Unknown_Esize (T) then
603 -- Set sizes if not set already
606 if Unknown_Esize (T) then
610 if Unknown_RM_Size (T) then
620 function Size_Known (T : Entity_Id) return Boolean is
628 if Size_Known_At_Compile_Time (T) then
631 -- Always True for scalar types. This is true even for generic formal
632 -- scalar types. We used to return False in the latter case, but the
633 -- size is known at compile time, even in the template, we just do
634 -- not know the exact size but that's not the point of this routine.
636 elsif Is_Scalar_Type (T)
637 or else Is_Task_Type (T)
643 elsif Is_Array_Type (T) then
645 -- String literals always have known size, and we can set it
647 if Ekind (T) = E_String_Literal_Subtype then
648 Set_Small_Size (T, Component_Size (T)
649 * String_Literal_Length (T));
652 -- Unconstrained types never have known at compile time size
654 elsif not Is_Constrained (T) then
657 -- Don't do any recursion on type with error posted, since we may
658 -- have a malformed type that leads us into a loop.
660 elsif Error_Posted (T) then
663 -- Otherwise if component size unknown, then array size unknown
665 elsif not Size_Known (Component_Type (T)) then
669 -- Check for all indexes static, and also compute possible size
670 -- (in case it is less than 32 and may be packable).
673 Esiz : Uint := Component_Size (T);
677 Index := First_Index (T);
678 while Present (Index) loop
679 if Nkind (Index) = N_Range then
680 Get_Index_Bounds (Index, Low, High);
682 elsif Error_Posted (Scalar_Range (Etype (Index))) then
686 Low := Type_Low_Bound (Etype (Index));
687 High := Type_High_Bound (Etype (Index));
690 if not Compile_Time_Known_Value (Low)
691 or else not Compile_Time_Known_Value (High)
692 or else Etype (Index) = Any_Type
697 Dim := Expr_Value (High) - Expr_Value (Low) + 1;
709 Set_Small_Size (T, Esiz);
713 -- Access types always have known at compile time sizes
715 elsif Is_Access_Type (T) then
718 -- For non-generic private types, go to underlying type if present
720 elsif Is_Private_Type (T)
721 and then not Is_Generic_Type (T)
722 and then Present (Underlying_Type (T))
724 -- Don't do any recursion on type with error posted, since we may
725 -- have a malformed type that leads us into a loop.
727 if Error_Posted (T) then
730 return Size_Known (Underlying_Type (T));
735 elsif Is_Record_Type (T) then
737 -- A class-wide type is never considered to have a known size
739 if Is_Class_Wide_Type (T) then
742 -- A subtype of a variant record must not have non-static
743 -- discriminanted components.
745 elsif T /= Base_Type (T)
746 and then not Static_Discriminated_Components (T)
750 -- Don't do any recursion on type with error posted, since we may
751 -- have a malformed type that leads us into a loop.
753 elsif Error_Posted (T) then
757 -- Now look at the components of the record
760 -- The following two variables are used to keep track of the
761 -- size of packed records if we can tell the size of the packed
762 -- record in the front end. Packed_Size_Known is True if so far
763 -- we can figure out the size. It is initialized to True for a
764 -- packed record, unless the record has discriminants. The
765 -- reason we eliminate the discriminated case is that we don't
766 -- know the way the back end lays out discriminated packed
767 -- records. If Packed_Size_Known is True, then Packed_Size is
768 -- the size in bits so far.
770 Packed_Size_Known : Boolean :=
772 and then not Has_Discriminants (T);
774 Packed_Size : Uint := Uint_0;
777 -- Test for variant part present
779 if Has_Discriminants (T)
780 and then Present (Parent (T))
781 and then Nkind (Parent (T)) = N_Full_Type_Declaration
782 and then Nkind (Type_Definition (Parent (T))) =
784 and then not Null_Present (Type_Definition (Parent (T)))
785 and then Present (Variant_Part
786 (Component_List (Type_Definition (Parent (T)))))
788 -- If variant part is present, and type is unconstrained,
789 -- then we must have defaulted discriminants, or a size
790 -- clause must be present for the type, or else the size
791 -- is definitely not known at compile time.
793 if not Is_Constrained (T)
795 No (Discriminant_Default_Value
796 (First_Discriminant (T)))
797 and then Unknown_Esize (T)
803 -- Loop through components
805 Comp := First_Component_Or_Discriminant (T);
806 while Present (Comp) loop
807 Ctyp := Etype (Comp);
809 -- We do not know the packed size if there is a component
810 -- clause present (we possibly could, but this would only
811 -- help in the case of a record with partial rep clauses.
812 -- That's because in the case of full rep clauses, the
813 -- size gets figured out anyway by a different circuit).
815 if Present (Component_Clause (Comp)) then
816 Packed_Size_Known := False;
819 -- We need to identify a component that is an array where
820 -- the index type is an enumeration type with non-standard
821 -- representation, and some bound of the type depends on a
824 -- This is because gigi computes the size by doing a
825 -- substitution of the appropriate discriminant value in
826 -- the size expression for the base type, and gigi is not
827 -- clever enough to evaluate the resulting expression (which
828 -- involves a call to rep_to_pos) at compile time.
830 -- It would be nice if gigi would either recognize that
831 -- this expression can be computed at compile time, or
832 -- alternatively figured out the size from the subtype
833 -- directly, where all the information is at hand ???
835 if Is_Array_Type (Etype (Comp))
836 and then Present (Packed_Array_Type (Etype (Comp)))
839 Ocomp : constant Entity_Id :=
840 Original_Record_Component (Comp);
841 OCtyp : constant Entity_Id := Etype (Ocomp);
847 Ind := First_Index (OCtyp);
848 while Present (Ind) loop
849 Indtyp := Etype (Ind);
851 if Is_Enumeration_Type (Indtyp)
852 and then Has_Non_Standard_Rep (Indtyp)
854 Lo := Type_Low_Bound (Indtyp);
855 Hi := Type_High_Bound (Indtyp);
857 if Is_Entity_Name (Lo)
858 and then Ekind (Entity (Lo)) = E_Discriminant
862 elsif Is_Entity_Name (Hi)
863 and then Ekind (Entity (Hi)) = E_Discriminant
874 -- Clearly size of record is not known if the size of one of
875 -- the components is not known.
877 if not Size_Known (Ctyp) then
881 -- Accumulate packed size if possible
883 if Packed_Size_Known then
885 -- We can only deal with elementary types, since for
886 -- non-elementary components, alignment enters into the
887 -- picture, and we don't know enough to handle proper
888 -- alignment in this context. Packed arrays count as
889 -- elementary if the representation is a modular type.
891 if Is_Elementary_Type (Ctyp)
892 or else (Is_Array_Type (Ctyp)
893 and then Present (Packed_Array_Type (Ctyp))
894 and then Is_Modular_Integer_Type
895 (Packed_Array_Type (Ctyp)))
897 -- If RM_Size is known and static, then we can
898 -- keep accumulating the packed size.
900 if Known_Static_RM_Size (Ctyp) then
902 -- A little glitch, to be removed sometime ???
903 -- gigi does not understand zero sizes yet.
905 if RM_Size (Ctyp) = Uint_0 then
906 Packed_Size_Known := False;
908 -- Normal case where we can keep accumulating the
909 -- packed array size.
912 Packed_Size := Packed_Size + RM_Size (Ctyp);
915 -- If we have a field whose RM_Size is not known then
916 -- we can't figure out the packed size here.
919 Packed_Size_Known := False;
922 -- If we have a non-elementary type we can't figure out
923 -- the packed array size (alignment issues).
926 Packed_Size_Known := False;
930 Next_Component_Or_Discriminant (Comp);
933 if Packed_Size_Known then
934 Set_Small_Size (T, Packed_Size);
940 -- All other cases, size not known at compile time
947 -------------------------------------
948 -- Static_Discriminated_Components --
949 -------------------------------------
951 function Static_Discriminated_Components
952 (T : Entity_Id) return Boolean
954 Constraint : Elmt_Id;
957 if Has_Discriminants (T)
958 and then Present (Discriminant_Constraint (T))
959 and then Present (First_Component (T))
961 Constraint := First_Elmt (Discriminant_Constraint (T));
962 while Present (Constraint) loop
963 if not Compile_Time_Known_Value (Node (Constraint)) then
967 Next_Elmt (Constraint);
972 end Static_Discriminated_Components;
974 -- Start of processing for Check_Compile_Time_Size
977 Set_Size_Known_At_Compile_Time (T, Size_Known (T));
978 end Check_Compile_Time_Size;
980 -----------------------------
981 -- Check_Debug_Info_Needed --
982 -----------------------------
984 procedure Check_Debug_Info_Needed (T : Entity_Id) is
986 if Debug_Info_Off (T) then
989 elsif Comes_From_Source (T)
990 or else Debug_Generated_Code
991 or else Debug_Flag_VV
992 or else Needs_Debug_Info (T)
994 Set_Debug_Info_Needed (T);
996 end Check_Debug_Info_Needed;
998 ----------------------------
999 -- Check_Strict_Alignment --
1000 ----------------------------
1002 procedure Check_Strict_Alignment (E : Entity_Id) is
1006 if Is_Tagged_Type (E) or else Is_Concurrent_Type (E) then
1007 Set_Strict_Alignment (E);
1009 elsif Is_Array_Type (E) then
1010 Set_Strict_Alignment (E, Strict_Alignment (Component_Type (E)));
1012 elsif Is_Record_Type (E) then
1013 if Is_Limited_Record (E) then
1014 Set_Strict_Alignment (E);
1018 Comp := First_Component (E);
1020 while Present (Comp) loop
1021 if not Is_Type (Comp)
1022 and then (Strict_Alignment (Etype (Comp))
1023 or else Is_Aliased (Comp))
1025 Set_Strict_Alignment (E);
1029 Next_Component (Comp);
1032 end Check_Strict_Alignment;
1034 -------------------------
1035 -- Check_Unsigned_Type --
1036 -------------------------
1038 procedure Check_Unsigned_Type (E : Entity_Id) is
1039 Ancestor : Entity_Id;
1044 if not Is_Discrete_Or_Fixed_Point_Type (E) then
1048 -- Do not attempt to analyze case where range was in error
1050 if Error_Posted (Scalar_Range (E)) then
1054 -- The situation that is non trivial is something like
1056 -- subtype x1 is integer range -10 .. +10;
1057 -- subtype x2 is x1 range 0 .. V1;
1058 -- subtype x3 is x2 range V2 .. V3;
1059 -- subtype x4 is x3 range V4 .. V5;
1061 -- where Vn are variables. Here the base type is signed, but we still
1062 -- know that x4 is unsigned because of the lower bound of x2.
1064 -- The only way to deal with this is to look up the ancestor chain
1068 if Ancestor = Any_Type or else Etype (Ancestor) = Any_Type then
1072 Lo_Bound := Type_Low_Bound (Ancestor);
1074 if Compile_Time_Known_Value (Lo_Bound) then
1076 if Expr_Rep_Value (Lo_Bound) >= 0 then
1077 Set_Is_Unsigned_Type (E, True);
1083 Ancestor := Ancestor_Subtype (Ancestor);
1085 -- If no ancestor had a static lower bound, go to base type
1087 if No (Ancestor) then
1089 -- Note: the reason we still check for a compile time known
1090 -- value for the base type is that at least in the case of
1091 -- generic formals, we can have bounds that fail this test,
1092 -- and there may be other cases in error situations.
1094 Btyp := Base_Type (E);
1096 if Btyp = Any_Type or else Etype (Btyp) = Any_Type then
1100 Lo_Bound := Type_Low_Bound (Base_Type (E));
1102 if Compile_Time_Known_Value (Lo_Bound)
1103 and then Expr_Rep_Value (Lo_Bound) >= 0
1105 Set_Is_Unsigned_Type (E, True);
1112 end Check_Unsigned_Type;
1114 -------------------------
1115 -- Is_Atomic_Aggregate --
1116 -------------------------
1118 function Is_Atomic_Aggregate
1120 Typ : Entity_Id) return Boolean
1122 Loc : constant Source_Ptr := Sloc (E);
1130 -- Array may be qualified, so find outer context
1132 if Nkind (Par) = N_Qualified_Expression then
1133 Par := Parent (Par);
1136 if Nkind_In (Par, N_Object_Declaration, N_Assignment_Statement)
1137 and then Comes_From_Source (Par)
1140 Make_Defining_Identifier (Loc,
1141 New_Internal_Name ('T'));
1144 Make_Object_Declaration (Loc,
1145 Defining_Identifier => Temp,
1146 Object_Definition => New_Occurrence_Of (Typ, Loc),
1147 Expression => Relocate_Node (E));
1148 Insert_Before (Par, New_N);
1151 Set_Expression (Par, New_Occurrence_Of (Temp, Loc));
1157 end Is_Atomic_Aggregate;
1163 -- Note: the easy coding for this procedure would be to just build a
1164 -- single list of freeze nodes and then insert them and analyze them
1165 -- all at once. This won't work, because the analysis of earlier freeze
1166 -- nodes may recursively freeze types which would otherwise appear later
1167 -- on in the freeze list. So we must analyze and expand the freeze nodes
1168 -- as they are generated.
1170 procedure Freeze_All (From : Entity_Id; After : in out Node_Id) is
1171 Loc : constant Source_Ptr := Sloc (After);
1175 procedure Freeze_All_Ent (From : Entity_Id; After : in out Node_Id);
1176 -- This is the internal recursive routine that does freezing of entities
1177 -- (but NOT the analysis of default expressions, which should not be
1178 -- recursive, we don't want to analyze those till we are sure that ALL
1179 -- the types are frozen).
1181 --------------------
1182 -- Freeze_All_Ent --
1183 --------------------
1185 procedure Freeze_All_Ent
1187 After : in out Node_Id)
1193 procedure Process_Flist;
1194 -- If freeze nodes are present, insert and analyze, and reset cursor
1195 -- for next insertion.
1201 procedure Process_Flist is
1203 if Is_Non_Empty_List (Flist) then
1204 Lastn := Next (After);
1205 Insert_List_After_And_Analyze (After, Flist);
1207 if Present (Lastn) then
1208 After := Prev (Lastn);
1210 After := Last (List_Containing (After));
1215 -- Start or processing for Freeze_All_Ent
1219 while Present (E) loop
1221 -- If the entity is an inner package which is not a package
1222 -- renaming, then its entities must be frozen at this point. Note
1223 -- that such entities do NOT get frozen at the end of the nested
1224 -- package itself (only library packages freeze).
1226 -- Same is true for task declarations, where anonymous records
1227 -- created for entry parameters must be frozen.
1229 if Ekind (E) = E_Package
1230 and then No (Renamed_Object (E))
1231 and then not Is_Child_Unit (E)
1232 and then not Is_Frozen (E)
1235 Install_Visible_Declarations (E);
1236 Install_Private_Declarations (E);
1238 Freeze_All (First_Entity (E), After);
1240 End_Package_Scope (E);
1242 elsif Ekind (E) in Task_Kind
1244 (Nkind (Parent (E)) = N_Task_Type_Declaration
1246 Nkind (Parent (E)) = N_Single_Task_Declaration)
1249 Freeze_All (First_Entity (E), After);
1252 -- For a derived tagged type, we must ensure that all the
1253 -- primitive operations of the parent have been frozen, so that
1254 -- their addresses will be in the parent's dispatch table at the
1255 -- point it is inherited.
1257 elsif Ekind (E) = E_Record_Type
1258 and then Is_Tagged_Type (E)
1259 and then Is_Tagged_Type (Etype (E))
1260 and then Is_Derived_Type (E)
1263 Prim_List : constant Elist_Id :=
1264 Primitive_Operations (Etype (E));
1270 Prim := First_Elmt (Prim_List);
1272 while Present (Prim) loop
1273 Subp := Node (Prim);
1275 if Comes_From_Source (Subp)
1276 and then not Is_Frozen (Subp)
1278 Flist := Freeze_Entity (Subp, Loc);
1287 if not Is_Frozen (E) then
1288 Flist := Freeze_Entity (E, Loc);
1292 -- If an incomplete type is still not frozen, this may be a
1293 -- premature freezing because of a body declaration that follows.
1294 -- Indicate where the freezing took place.
1296 -- If the freezing is caused by the end of the current declarative
1297 -- part, it is a Taft Amendment type, and there is no error.
1299 if not Is_Frozen (E)
1300 and then Ekind (E) = E_Incomplete_Type
1303 Bod : constant Node_Id := Next (After);
1306 if (Nkind (Bod) = N_Subprogram_Body
1307 or else Nkind (Bod) = N_Entry_Body
1308 or else Nkind (Bod) = N_Package_Body
1309 or else Nkind (Bod) = N_Protected_Body
1310 or else Nkind (Bod) = N_Task_Body
1311 or else Nkind (Bod) in N_Body_Stub)
1313 List_Containing (After) = List_Containing (Parent (E))
1315 Error_Msg_Sloc := Sloc (Next (After));
1317 ("type& is frozen# before its full declaration",
1327 -- Start of processing for Freeze_All
1330 Freeze_All_Ent (From, After);
1332 -- Now that all types are frozen, we can deal with default expressions
1333 -- that require us to build a default expression functions. This is the
1334 -- point at which such functions are constructed (after all types that
1335 -- might be used in such expressions have been frozen).
1337 -- We also add finalization chains to access types whose designated
1338 -- types are controlled. This is normally done when freezing the type,
1339 -- but this misses recursive type definitions where the later members
1340 -- of the recursion introduce controlled components.
1342 -- Loop through entities
1345 while Present (E) loop
1346 if Is_Subprogram (E) then
1348 if not Default_Expressions_Processed (E) then
1349 Process_Default_Expressions (E, After);
1352 if not Has_Completion (E) then
1353 Decl := Unit_Declaration_Node (E);
1355 if Nkind (Decl) = N_Subprogram_Renaming_Declaration then
1356 Build_And_Analyze_Renamed_Body (Decl, E, After);
1358 elsif Nkind (Decl) = N_Subprogram_Declaration
1359 and then Present (Corresponding_Body (Decl))
1361 Nkind (Unit_Declaration_Node (Corresponding_Body (Decl)))
1362 = N_Subprogram_Renaming_Declaration
1364 Build_And_Analyze_Renamed_Body
1365 (Decl, Corresponding_Body (Decl), After);
1369 elsif Ekind (E) in Task_Kind
1371 (Nkind (Parent (E)) = N_Task_Type_Declaration
1373 Nkind (Parent (E)) = N_Single_Task_Declaration)
1378 Ent := First_Entity (E);
1380 while Present (Ent) loop
1383 and then not Default_Expressions_Processed (Ent)
1385 Process_Default_Expressions (Ent, After);
1392 elsif Is_Access_Type (E)
1393 and then Comes_From_Source (E)
1394 and then Ekind (Directly_Designated_Type (E)) = E_Incomplete_Type
1395 and then Needs_Finalization (Designated_Type (E))
1396 and then No (Associated_Final_Chain (E))
1398 Build_Final_List (Parent (E), E);
1405 -----------------------
1406 -- Freeze_And_Append --
1407 -----------------------
1409 procedure Freeze_And_Append
1412 Result : in out List_Id)
1414 L : constant List_Id := Freeze_Entity (Ent, Loc);
1416 if Is_Non_Empty_List (L) then
1417 if Result = No_List then
1420 Append_List (L, Result);
1423 end Freeze_And_Append;
1429 procedure Freeze_Before (N : Node_Id; T : Entity_Id) is
1430 Freeze_Nodes : constant List_Id := Freeze_Entity (T, Sloc (N));
1432 if Is_Non_Empty_List (Freeze_Nodes) then
1433 Insert_Actions (N, Freeze_Nodes);
1441 function Freeze_Entity (E : Entity_Id; Loc : Source_Ptr) return List_Id is
1442 Test_E : Entity_Id := E;
1450 Has_Default_Initialization : Boolean := False;
1451 -- This flag gets set to true for a variable with default initialization
1453 procedure Check_Current_Instance (Comp_Decl : Node_Id);
1454 -- Check that an Access or Unchecked_Access attribute with a prefix
1455 -- which is the current instance type can only be applied when the type
1458 procedure Check_Suspicious_Modulus (Utype : Entity_Id);
1459 -- Give warning for modulus of 8, 16, 32, or 64 given as an explicit
1460 -- integer literal without an explicit corresponding size clause. The
1461 -- caller has checked that Utype is a modular integer type.
1463 function After_Last_Declaration return Boolean;
1464 -- If Loc is a freeze_entity that appears after the last declaration
1465 -- in the scope, inhibit error messages on late completion.
1467 procedure Freeze_Record_Type (Rec : Entity_Id);
1468 -- Freeze each component, handle some representation clauses, and freeze
1469 -- primitive operations if this is a tagged type.
1471 ----------------------------
1472 -- After_Last_Declaration --
1473 ----------------------------
1475 function After_Last_Declaration return Boolean is
1476 Spec : constant Node_Id := Parent (Current_Scope);
1478 if Nkind (Spec) = N_Package_Specification then
1479 if Present (Private_Declarations (Spec)) then
1480 return Loc >= Sloc (Last (Private_Declarations (Spec)));
1481 elsif Present (Visible_Declarations (Spec)) then
1482 return Loc >= Sloc (Last (Visible_Declarations (Spec)));
1489 end After_Last_Declaration;
1491 ----------------------------
1492 -- Check_Current_Instance --
1493 ----------------------------
1495 procedure Check_Current_Instance (Comp_Decl : Node_Id) is
1497 Rec_Type : constant Entity_Id :=
1498 Scope (Defining_Identifier (Comp_Decl));
1500 Decl : constant Node_Id := Parent (Rec_Type);
1502 function Process (N : Node_Id) return Traverse_Result;
1503 -- Process routine to apply check to given node
1509 function Process (N : Node_Id) return Traverse_Result is
1512 when N_Attribute_Reference =>
1513 if (Attribute_Name (N) = Name_Access
1515 Attribute_Name (N) = Name_Unchecked_Access)
1516 and then Is_Entity_Name (Prefix (N))
1517 and then Is_Type (Entity (Prefix (N)))
1518 and then Entity (Prefix (N)) = E
1521 ("current instance must be a limited type", Prefix (N));
1527 when others => return OK;
1531 procedure Traverse is new Traverse_Proc (Process);
1533 -- Start of processing for Check_Current_Instance
1536 -- In Ada95, the (imprecise) rule is that the current instance of a
1537 -- limited type is aliased. In Ada2005, limitedness must be explicit:
1538 -- either a tagged type, or a limited record.
1540 if Is_Limited_Type (Rec_Type)
1541 and then (Ada_Version < Ada_05 or else Is_Tagged_Type (Rec_Type))
1545 elsif Nkind (Decl) = N_Full_Type_Declaration
1546 and then Limited_Present (Type_Definition (Decl))
1551 Traverse (Comp_Decl);
1553 end Check_Current_Instance;
1555 ------------------------------
1556 -- Check_Suspicious_Modulus --
1557 ------------------------------
1559 procedure Check_Suspicious_Modulus (Utype : Entity_Id) is
1560 Decl : constant Node_Id := Declaration_Node (Underlying_Type (Utype));
1563 if Nkind (Decl) = N_Full_Type_Declaration then
1565 Tdef : constant Node_Id := Type_Definition (Decl);
1567 if Nkind (Tdef) = N_Modular_Type_Definition then
1569 Modulus : constant Node_Id :=
1570 Original_Node (Expression (Tdef));
1572 if Nkind (Modulus) = N_Integer_Literal then
1574 Modv : constant Uint := Intval (Modulus);
1575 Sizv : constant Uint := RM_Size (Utype);
1578 -- First case, modulus and size are the same. This
1579 -- happens if you have something like mod 32, with
1580 -- an explicit size of 32, this is for sure a case
1581 -- where the warning is given, since it is seems
1582 -- very unlikely that someone would want e.g. a
1583 -- five bit type stored in 32 bits. It is much
1584 -- more likely they wanted a 32-bit type.
1589 -- Second case, the modulus is 32 or 64 and no
1590 -- size clause is present. This is a less clear
1591 -- case for giving the warning, but in the case
1592 -- of 32/64 (5-bit or 6-bit types) these seem rare
1593 -- enough that it is a likely error (and in any
1594 -- case using 2**5 or 2**6 in these cases seems
1595 -- clearer. We don't include 8 or 16 here, simply
1596 -- because in practice 3-bit and 4-bit types are
1597 -- more common and too many false positives if
1598 -- we warn in these cases.
1600 elsif not Has_Size_Clause (Utype)
1601 and then (Modv = Uint_32 or else Modv = Uint_64)
1605 -- No warning needed
1611 -- If we fall through, give warning
1613 Error_Msg_Uint_1 := Modv;
1615 ("?2 '*'*^' may have been intended here",
1623 end Check_Suspicious_Modulus;
1625 ------------------------
1626 -- Freeze_Record_Type --
1627 ------------------------
1629 procedure Freeze_Record_Type (Rec : Entity_Id) is
1636 pragma Warnings (Off, Junk);
1638 Unplaced_Component : Boolean := False;
1639 -- Set True if we find at least one component with no component
1640 -- clause (used to warn about useless Pack pragmas).
1642 Placed_Component : Boolean := False;
1643 -- Set True if we find at least one component with a component
1644 -- clause (used to warn about useless Bit_Order pragmas, and also
1645 -- to detect cases where Implicit_Packing may have an effect).
1647 All_Scalar_Components : Boolean := True;
1648 -- Set False if we encounter a component of a non-scalar type
1650 Scalar_Component_Total_RM_Size : Uint := Uint_0;
1651 Scalar_Component_Total_Esize : Uint := Uint_0;
1652 -- Accumulates total RM_Size values and total Esize values of all
1653 -- scalar components. Used for processing of Implicit_Packing.
1655 function Check_Allocator (N : Node_Id) return Node_Id;
1656 -- If N is an allocator, possibly wrapped in one or more level of
1657 -- qualified expression(s), return the inner allocator node, else
1660 procedure Check_Itype (Typ : Entity_Id);
1661 -- If the component subtype is an access to a constrained subtype of
1662 -- an already frozen type, make the subtype frozen as well. It might
1663 -- otherwise be frozen in the wrong scope, and a freeze node on
1664 -- subtype has no effect. Similarly, if the component subtype is a
1665 -- regular (not protected) access to subprogram, set the anonymous
1666 -- subprogram type to frozen as well, to prevent an out-of-scope
1667 -- freeze node at some eventual point of call. Protected operations
1668 -- are handled elsewhere.
1670 ---------------------
1671 -- Check_Allocator --
1672 ---------------------
1674 function Check_Allocator (N : Node_Id) return Node_Id is
1679 if Nkind (Inner) = N_Allocator then
1681 elsif Nkind (Inner) = N_Qualified_Expression then
1682 Inner := Expression (Inner);
1687 end Check_Allocator;
1693 procedure Check_Itype (Typ : Entity_Id) is
1694 Desig : constant Entity_Id := Designated_Type (Typ);
1697 if not Is_Frozen (Desig)
1698 and then Is_Frozen (Base_Type (Desig))
1700 Set_Is_Frozen (Desig);
1702 -- In addition, add an Itype_Reference to ensure that the
1703 -- access subtype is elaborated early enough. This cannot be
1704 -- done if the subtype may depend on discriminants.
1706 if Ekind (Comp) = E_Component
1707 and then Is_Itype (Etype (Comp))
1708 and then not Has_Discriminants (Rec)
1710 IR := Make_Itype_Reference (Sloc (Comp));
1711 Set_Itype (IR, Desig);
1714 Result := New_List (IR);
1716 Append (IR, Result);
1720 elsif Ekind (Typ) = E_Anonymous_Access_Subprogram_Type
1721 and then Convention (Desig) /= Convention_Protected
1723 Set_Is_Frozen (Desig);
1727 -- Start of processing for Freeze_Record_Type
1730 -- If this is a subtype of a controlled type, declared without a
1731 -- constraint, the _controller may not appear in the component list
1732 -- if the parent was not frozen at the point of subtype declaration.
1733 -- Inherit the _controller component now.
1735 if Rec /= Base_Type (Rec)
1736 and then Has_Controlled_Component (Rec)
1738 if Nkind (Parent (Rec)) = N_Subtype_Declaration
1739 and then Is_Entity_Name (Subtype_Indication (Parent (Rec)))
1741 Set_First_Entity (Rec, First_Entity (Base_Type (Rec)));
1743 -- If this is an internal type without a declaration, as for
1744 -- record component, the base type may not yet be frozen, and its
1745 -- controller has not been created. Add an explicit freeze node
1746 -- for the itype, so it will be frozen after the base type. This
1747 -- freeze node is used to communicate with the expander, in order
1748 -- to create the controller for the enclosing record, and it is
1749 -- deleted afterwards (see exp_ch3). It must not be created when
1750 -- expansion is off, because it might appear in the wrong context
1751 -- for the back end.
1753 elsif Is_Itype (Rec)
1754 and then Has_Delayed_Freeze (Base_Type (Rec))
1756 Nkind (Associated_Node_For_Itype (Rec)) =
1757 N_Component_Declaration
1758 and then Expander_Active
1760 Ensure_Freeze_Node (Rec);
1764 -- Freeze components and embedded subtypes
1766 Comp := First_Entity (Rec);
1768 while Present (Comp) loop
1770 -- First handle the (real) component case
1772 if Ekind (Comp) = E_Component
1773 or else Ekind (Comp) = E_Discriminant
1776 CC : constant Node_Id := Component_Clause (Comp);
1779 -- Freezing a record type freezes the type of each of its
1780 -- components. However, if the type of the component is
1781 -- part of this record, we do not want or need a separate
1782 -- Freeze_Node. Note that Is_Itype is wrong because that's
1783 -- also set in private type cases. We also can't check for
1784 -- the Scope being exactly Rec because of private types and
1785 -- record extensions.
1787 if Is_Itype (Etype (Comp))
1788 and then Is_Record_Type (Underlying_Type
1789 (Scope (Etype (Comp))))
1791 Undelay_Type (Etype (Comp));
1794 Freeze_And_Append (Etype (Comp), Loc, Result);
1796 -- Check for error of component clause given for variable
1797 -- sized type. We have to delay this test till this point,
1798 -- since the component type has to be frozen for us to know
1799 -- if it is variable length. We omit this test in a generic
1800 -- context, it will be applied at instantiation time.
1802 if Present (CC) then
1803 Placed_Component := True;
1805 if Inside_A_Generic then
1809 Size_Known_At_Compile_Time
1810 (Underlying_Type (Etype (Comp)))
1813 ("component clause not allowed for variable " &
1814 "length component", CC);
1818 Unplaced_Component := True;
1821 -- Case of component requires byte alignment
1823 if Must_Be_On_Byte_Boundary (Etype (Comp)) then
1825 -- Set the enclosing record to also require byte align
1827 Set_Must_Be_On_Byte_Boundary (Rec);
1829 -- Check for component clause that is inconsistent with
1830 -- the required byte boundary alignment.
1833 and then Normalized_First_Bit (Comp) mod
1834 System_Storage_Unit /= 0
1837 ("component & must be byte aligned",
1838 Component_Name (Component_Clause (Comp)));
1842 -- If component clause is present, then deal with the non-
1843 -- default bit order case for Ada 95 mode. The required
1844 -- processing for Ada 2005 mode is handled separately after
1845 -- processing all components.
1847 -- We only do this processing for the base type, and in
1848 -- fact that's important, since otherwise if there are
1849 -- record subtypes, we could reverse the bits once for
1850 -- each subtype, which would be incorrect.
1853 and then Reverse_Bit_Order (Rec)
1854 and then Ekind (E) = E_Record_Type
1855 and then Ada_Version <= Ada_95
1858 CFB : constant Uint := Component_Bit_Offset (Comp);
1859 CSZ : constant Uint := Esize (Comp);
1860 CLC : constant Node_Id := Component_Clause (Comp);
1861 Pos : constant Node_Id := Position (CLC);
1862 FB : constant Node_Id := First_Bit (CLC);
1864 Storage_Unit_Offset : constant Uint :=
1865 CFB / System_Storage_Unit;
1867 Start_Bit : constant Uint :=
1868 CFB mod System_Storage_Unit;
1871 -- Cases where field goes over storage unit boundary
1873 if Start_Bit + CSZ > System_Storage_Unit then
1875 -- Allow multi-byte field but generate warning
1877 if Start_Bit mod System_Storage_Unit = 0
1878 and then CSZ mod System_Storage_Unit = 0
1881 ("multi-byte field specified with non-standard"
1882 & " Bit_Order?", CLC);
1884 if Bytes_Big_Endian then
1886 ("bytes are not reversed "
1887 & "(component is big-endian)?", CLC);
1890 ("bytes are not reversed "
1891 & "(component is little-endian)?", CLC);
1894 -- Do not allow non-contiguous field
1898 ("attempt to specify non-contiguous field "
1899 & "not permitted", CLC);
1901 ("\caused by non-standard Bit_Order "
1902 & "specified", CLC);
1904 ("\consider possibility of using "
1905 & "Ada 2005 mode here", CLC);
1908 -- Case where field fits in one storage unit
1911 -- Give warning if suspicious component clause
1913 if Intval (FB) >= System_Storage_Unit
1914 and then Warn_On_Reverse_Bit_Order
1917 ("?Bit_Order clause does not affect " &
1918 "byte ordering", Pos);
1920 Intval (Pos) + Intval (FB) /
1921 System_Storage_Unit;
1923 ("?position normalized to ^ before bit " &
1924 "order interpreted", Pos);
1927 -- Here is where we fix up the Component_Bit_Offset
1928 -- value to account for the reverse bit order.
1929 -- Some examples of what needs to be done are:
1931 -- First_Bit .. Last_Bit Component_Bit_Offset
1934 -- 0 .. 0 7 .. 7 0 7
1935 -- 0 .. 1 6 .. 7 0 6
1936 -- 0 .. 2 5 .. 7 0 5
1937 -- 0 .. 7 0 .. 7 0 4
1939 -- 1 .. 1 6 .. 6 1 6
1940 -- 1 .. 4 3 .. 6 1 3
1941 -- 4 .. 7 0 .. 3 4 0
1943 -- The general rule is that the first bit is
1944 -- is obtained by subtracting the old ending bit
1945 -- from storage_unit - 1.
1947 Set_Component_Bit_Offset
1949 (Storage_Unit_Offset * System_Storage_Unit) +
1950 (System_Storage_Unit - 1) -
1951 (Start_Bit + CSZ - 1));
1953 Set_Normalized_First_Bit
1955 Component_Bit_Offset (Comp) mod
1956 System_Storage_Unit);
1963 -- Gather data for possible Implicit_Packing later
1965 if not Is_Scalar_Type (Etype (Comp)) then
1966 All_Scalar_Components := False;
1968 Scalar_Component_Total_RM_Size :=
1969 Scalar_Component_Total_RM_Size + RM_Size (Etype (Comp));
1970 Scalar_Component_Total_Esize :=
1971 Scalar_Component_Total_Esize + Esize (Etype (Comp));
1974 -- If the component is an Itype with Delayed_Freeze and is either
1975 -- a record or array subtype and its base type has not yet been
1976 -- frozen, we must remove this from the entity list of this
1977 -- record and put it on the entity list of the scope of its base
1978 -- type. Note that we know that this is not the type of a
1979 -- component since we cleared Has_Delayed_Freeze for it in the
1980 -- previous loop. Thus this must be the Designated_Type of an
1981 -- access type, which is the type of a component.
1984 and then Is_Type (Scope (Comp))
1985 and then Is_Composite_Type (Comp)
1986 and then Base_Type (Comp) /= Comp
1987 and then Has_Delayed_Freeze (Comp)
1988 and then not Is_Frozen (Base_Type (Comp))
1991 Will_Be_Frozen : Boolean := False;
1995 -- We have a pretty bad kludge here. Suppose Rec is subtype
1996 -- being defined in a subprogram that's created as part of
1997 -- the freezing of Rec'Base. In that case, we know that
1998 -- Comp'Base must have already been frozen by the time we
1999 -- get to elaborate this because Gigi doesn't elaborate any
2000 -- bodies until it has elaborated all of the declarative
2001 -- part. But Is_Frozen will not be set at this point because
2002 -- we are processing code in lexical order.
2004 -- We detect this case by going up the Scope chain of Rec
2005 -- and seeing if we have a subprogram scope before reaching
2006 -- the top of the scope chain or that of Comp'Base. If we
2007 -- do, then mark that Comp'Base will actually be frozen. If
2008 -- so, we merely undelay it.
2011 while Present (S) loop
2012 if Is_Subprogram (S) then
2013 Will_Be_Frozen := True;
2015 elsif S = Scope (Base_Type (Comp)) then
2022 if Will_Be_Frozen then
2023 Undelay_Type (Comp);
2025 if Present (Prev) then
2026 Set_Next_Entity (Prev, Next_Entity (Comp));
2028 Set_First_Entity (Rec, Next_Entity (Comp));
2031 -- Insert in entity list of scope of base type (which
2032 -- must be an enclosing scope, because still unfrozen).
2034 Append_Entity (Comp, Scope (Base_Type (Comp)));
2038 -- If the component is an access type with an allocator as default
2039 -- value, the designated type will be frozen by the corresponding
2040 -- expression in init_proc. In order to place the freeze node for
2041 -- the designated type before that for the current record type,
2044 -- Same process if the component is an array of access types,
2045 -- initialized with an aggregate. If the designated type is
2046 -- private, it cannot contain allocators, and it is premature
2047 -- to freeze the type, so we check for this as well.
2049 elsif Is_Access_Type (Etype (Comp))
2050 and then Present (Parent (Comp))
2051 and then Present (Expression (Parent (Comp)))
2054 Alloc : constant Node_Id :=
2055 Check_Allocator (Expression (Parent (Comp)));
2058 if Present (Alloc) then
2060 -- If component is pointer to a classwide type, freeze
2061 -- the specific type in the expression being allocated.
2062 -- The expression may be a subtype indication, in which
2063 -- case freeze the subtype mark.
2065 if Is_Class_Wide_Type
2066 (Designated_Type (Etype (Comp)))
2068 if Is_Entity_Name (Expression (Alloc)) then
2070 (Entity (Expression (Alloc)), Loc, Result);
2072 Nkind (Expression (Alloc)) = N_Subtype_Indication
2075 (Entity (Subtype_Mark (Expression (Alloc))),
2079 elsif Is_Itype (Designated_Type (Etype (Comp))) then
2080 Check_Itype (Etype (Comp));
2084 (Designated_Type (Etype (Comp)), Loc, Result);
2089 elsif Is_Access_Type (Etype (Comp))
2090 and then Is_Itype (Designated_Type (Etype (Comp)))
2092 Check_Itype (Etype (Comp));
2094 elsif Is_Array_Type (Etype (Comp))
2095 and then Is_Access_Type (Component_Type (Etype (Comp)))
2096 and then Present (Parent (Comp))
2097 and then Nkind (Parent (Comp)) = N_Component_Declaration
2098 and then Present (Expression (Parent (Comp)))
2099 and then Nkind (Expression (Parent (Comp))) = N_Aggregate
2100 and then Is_Fully_Defined
2101 (Designated_Type (Component_Type (Etype (Comp))))
2105 (Component_Type (Etype (Comp))), Loc, Result);
2112 -- Deal with pragma Bit_Order
2114 if Reverse_Bit_Order (Rec) and then Base_Type (Rec) = Rec then
2115 if not Placed_Component then
2117 Get_Attribute_Definition_Clause (Rec, Attribute_Bit_Order);
2119 ("?Bit_Order specification has no effect", ADC);
2121 ("\?since no component clauses were specified", ADC);
2123 -- Here is where we do Ada 2005 processing for bit order (the Ada
2124 -- 95 case was already taken care of above).
2126 elsif Ada_Version >= Ada_05 then
2127 Adjust_Record_For_Reverse_Bit_Order (Rec);
2131 -- Set OK_To_Reorder_Components depending on debug flags
2133 if Rec = Base_Type (Rec)
2134 and then Convention (Rec) = Convention_Ada
2136 if (Has_Discriminants (Rec) and then Debug_Flag_Dot_V)
2138 (not Has_Discriminants (Rec) and then Debug_Flag_Dot_R)
2140 Set_OK_To_Reorder_Components (Rec);
2144 -- Check for useless pragma Pack when all components placed. We only
2145 -- do this check for record types, not subtypes, since a subtype may
2146 -- have all its components placed, and it still makes perfectly good
2147 -- sense to pack other subtypes or the parent type. We do not give
2148 -- this warning if Optimize_Alignment is set to Space, since the
2149 -- pragma Pack does have an effect in this case (it always resets
2150 -- the alignment to one).
2152 if Ekind (Rec) = E_Record_Type
2153 and then Is_Packed (Rec)
2154 and then not Unplaced_Component
2155 and then Optimize_Alignment /= 'S'
2157 -- Reset packed status. Probably not necessary, but we do it so
2158 -- that there is no chance of the back end doing something strange
2159 -- with this redundant indication of packing.
2161 Set_Is_Packed (Rec, False);
2163 -- Give warning if redundant constructs warnings on
2165 if Warn_On_Redundant_Constructs then
2167 ("?pragma Pack has no effect, no unplaced components",
2168 Get_Rep_Pragma (Rec, Name_Pack));
2172 -- If this is the record corresponding to a remote type, freeze the
2173 -- remote type here since that is what we are semantically freezing.
2174 -- This prevents the freeze node for that type in an inner scope.
2176 -- Also, Check for controlled components and unchecked unions.
2177 -- Finally, enforce the restriction that access attributes with a
2178 -- current instance prefix can only apply to limited types.
2180 if Ekind (Rec) = E_Record_Type then
2181 if Present (Corresponding_Remote_Type (Rec)) then
2183 (Corresponding_Remote_Type (Rec), Loc, Result);
2186 Comp := First_Component (Rec);
2187 while Present (Comp) loop
2188 if Has_Controlled_Component (Etype (Comp))
2189 or else (Chars (Comp) /= Name_uParent
2190 and then Is_Controlled (Etype (Comp)))
2191 or else (Is_Protected_Type (Etype (Comp))
2193 (Corresponding_Record_Type (Etype (Comp)))
2194 and then Has_Controlled_Component
2195 (Corresponding_Record_Type (Etype (Comp))))
2197 Set_Has_Controlled_Component (Rec);
2201 if Has_Unchecked_Union (Etype (Comp)) then
2202 Set_Has_Unchecked_Union (Rec);
2205 if Has_Per_Object_Constraint (Comp) then
2207 -- Scan component declaration for likely misuses of current
2208 -- instance, either in a constraint or a default expression.
2210 Check_Current_Instance (Parent (Comp));
2213 Next_Component (Comp);
2217 Set_Component_Alignment_If_Not_Set (Rec);
2219 -- For first subtypes, check if there are any fixed-point fields with
2220 -- component clauses, where we must check the size. This is not done
2221 -- till the freeze point, since for fixed-point types, we do not know
2222 -- the size until the type is frozen. Similar processing applies to
2223 -- bit packed arrays.
2225 if Is_First_Subtype (Rec) then
2226 Comp := First_Component (Rec);
2228 while Present (Comp) loop
2229 if Present (Component_Clause (Comp))
2230 and then (Is_Fixed_Point_Type (Etype (Comp))
2232 Is_Bit_Packed_Array (Etype (Comp)))
2235 (Component_Name (Component_Clause (Comp)),
2241 Next_Component (Comp);
2245 -- Generate warning for applying C or C++ convention to a record
2246 -- with discriminants. This is suppressed for the unchecked union
2247 -- case, since the whole point in this case is interface C. We also
2248 -- do not generate this within instantiations, since we will have
2249 -- generated a message on the template.
2251 if Has_Discriminants (E)
2252 and then not Is_Unchecked_Union (E)
2253 and then (Convention (E) = Convention_C
2255 Convention (E) = Convention_CPP)
2256 and then Comes_From_Source (E)
2257 and then not In_Instance
2258 and then not Has_Warnings_Off (E)
2259 and then not Has_Warnings_Off (Base_Type (E))
2262 Cprag : constant Node_Id := Get_Rep_Pragma (E, Name_Convention);
2266 if Present (Cprag) then
2267 A2 := Next (First (Pragma_Argument_Associations (Cprag)));
2269 if Convention (E) = Convention_C then
2271 ("?variant record has no direct equivalent in C", A2);
2274 ("?variant record has no direct equivalent in C++", A2);
2278 ("\?use of convention for type& is dubious", A2, E);
2283 -- See if Implicit_Packing would work
2285 if not Is_Packed (Rec)
2286 and then not Placed_Component
2287 and then Has_Size_Clause (Rec)
2288 and then All_Scalar_Components
2289 and then not Has_Discriminants (Rec)
2290 and then Esize (Rec) < Scalar_Component_Total_Esize
2291 and then Esize (Rec) >= Scalar_Component_Total_RM_Size
2293 -- If implicit packing enabled, do it
2295 if Implicit_Packing then
2296 Set_Is_Packed (Rec);
2298 -- Otherwise flag the size clause
2302 Sz : constant Node_Id := Size_Clause (Rec);
2304 Error_Msg_NE -- CODEFIX
2305 ("size given for& too small", Sz, Rec);
2306 Error_Msg_N -- CODEFIX
2307 ("\use explicit pragma Pack "
2308 & "or use pragma Implicit_Packing", Sz);
2312 end Freeze_Record_Type;
2314 -- Start of processing for Freeze_Entity
2317 -- We are going to test for various reasons why this entity need not be
2318 -- frozen here, but in the case of an Itype that's defined within a
2319 -- record, that test actually applies to the record.
2321 if Is_Itype (E) and then Is_Record_Type (Scope (E)) then
2322 Test_E := Scope (E);
2323 elsif Is_Itype (E) and then Present (Underlying_Type (Scope (E)))
2324 and then Is_Record_Type (Underlying_Type (Scope (E)))
2326 Test_E := Underlying_Type (Scope (E));
2329 -- Do not freeze if already frozen since we only need one freeze node
2331 if Is_Frozen (E) then
2334 -- It is improper to freeze an external entity within a generic because
2335 -- its freeze node will appear in a non-valid context. The entity will
2336 -- be frozen in the proper scope after the current generic is analyzed.
2338 elsif Inside_A_Generic and then External_Ref_In_Generic (Test_E) then
2341 -- Do not freeze a global entity within an inner scope created during
2342 -- expansion. A call to subprogram E within some internal procedure
2343 -- (a stream attribute for example) might require freezing E, but the
2344 -- freeze node must appear in the same declarative part as E itself.
2345 -- The two-pass elaboration mechanism in gigi guarantees that E will
2346 -- be frozen before the inner call is elaborated. We exclude constants
2347 -- from this test, because deferred constants may be frozen early, and
2348 -- must be diagnosed (e.g. in the case of a deferred constant being used
2349 -- in a default expression). If the enclosing subprogram comes from
2350 -- source, or is a generic instance, then the freeze point is the one
2351 -- mandated by the language, and we freeze the entity. A subprogram that
2352 -- is a child unit body that acts as a spec does not have a spec that
2353 -- comes from source, but can only come from source.
2355 elsif In_Open_Scopes (Scope (Test_E))
2356 and then Scope (Test_E) /= Current_Scope
2357 and then Ekind (Test_E) /= E_Constant
2360 S : Entity_Id := Current_Scope;
2363 while Present (S) loop
2364 if Is_Overloadable (S) then
2365 if Comes_From_Source (S)
2366 or else Is_Generic_Instance (S)
2367 or else Is_Child_Unit (S)
2379 -- Similarly, an inlined instance body may make reference to global
2380 -- entities, but these references cannot be the proper freezing point
2381 -- for them, and in the absence of inlining freezing will take place in
2382 -- their own scope. Normally instance bodies are analyzed after the
2383 -- enclosing compilation, and everything has been frozen at the proper
2384 -- place, but with front-end inlining an instance body is compiled
2385 -- before the end of the enclosing scope, and as a result out-of-order
2386 -- freezing must be prevented.
2388 elsif Front_End_Inlining
2389 and then In_Instance_Body
2390 and then Present (Scope (Test_E))
2393 S : Entity_Id := Scope (Test_E);
2396 while Present (S) loop
2397 if Is_Generic_Instance (S) then
2410 -- Here to freeze the entity
2415 -- Case of entity being frozen is other than a type
2417 if not Is_Type (E) then
2419 -- If entity is exported or imported and does not have an external
2420 -- name, now is the time to provide the appropriate default name.
2421 -- Skip this if the entity is stubbed, since we don't need a name
2422 -- for any stubbed routine.
2424 if (Is_Imported (E) or else Is_Exported (E))
2425 and then No (Interface_Name (E))
2426 and then Convention (E) /= Convention_Stubbed
2428 Set_Encoded_Interface_Name
2429 (E, Get_Default_External_Name (E));
2431 -- If entity is an atomic object appearing in a declaration and
2432 -- the expression is an aggregate, assign it to a temporary to
2433 -- ensure that the actual assignment is done atomically rather
2434 -- than component-wise (the assignment to the temp may be done
2435 -- component-wise, but that is harmless).
2438 and then Nkind (Parent (E)) = N_Object_Declaration
2439 and then Present (Expression (Parent (E)))
2440 and then Nkind (Expression (Parent (E))) = N_Aggregate
2442 Is_Atomic_Aggregate (Expression (Parent (E)), Etype (E))
2447 -- For a subprogram, freeze all parameter types and also the return
2448 -- type (RM 13.14(14)). However skip this for internal subprograms.
2449 -- This is also the point where any extra formal parameters are
2450 -- created since we now know whether the subprogram will use a
2451 -- foreign convention.
2453 if Is_Subprogram (E) then
2454 if not Is_Internal (E) then
2458 Warn_Node : Node_Id;
2461 -- Loop through formals
2463 Formal := First_Formal (E);
2464 while Present (Formal) loop
2465 F_Type := Etype (Formal);
2466 Freeze_And_Append (F_Type, Loc, Result);
2468 if Is_Private_Type (F_Type)
2469 and then Is_Private_Type (Base_Type (F_Type))
2470 and then No (Full_View (Base_Type (F_Type)))
2471 and then not Is_Generic_Type (F_Type)
2472 and then not Is_Derived_Type (F_Type)
2474 -- If the type of a formal is incomplete, subprogram
2475 -- is being frozen prematurely. Within an instance
2476 -- (but not within a wrapper package) this is an
2477 -- artifact of our need to regard the end of an
2478 -- instantiation as a freeze point. Otherwise it is
2479 -- a definite error.
2482 Set_Is_Frozen (E, False);
2485 elsif not After_Last_Declaration
2486 and then not Freezing_Library_Level_Tagged_Type
2488 Error_Msg_Node_1 := F_Type;
2490 ("type& must be fully defined before this point",
2495 -- Check suspicious parameter for C function. These tests
2496 -- apply only to exported/imported subprograms.
2498 if Warn_On_Export_Import
2499 and then Comes_From_Source (E)
2500 and then (Convention (E) = Convention_C
2502 Convention (E) = Convention_CPP)
2503 and then (Is_Imported (E) or else Is_Exported (E))
2504 and then Convention (E) /= Convention (Formal)
2505 and then not Has_Warnings_Off (E)
2506 and then not Has_Warnings_Off (F_Type)
2507 and then not Has_Warnings_Off (Formal)
2509 Error_Msg_Qual_Level := 1;
2511 -- Check suspicious use of fat C pointer
2513 if Is_Access_Type (F_Type)
2514 and then Esize (F_Type) > Ttypes.System_Address_Size
2517 ("?type of & does not correspond "
2518 & "to C pointer!", Formal);
2520 -- Check suspicious return of boolean
2522 elsif Root_Type (F_Type) = Standard_Boolean
2523 and then Convention (F_Type) = Convention_Ada
2524 and then not Has_Warnings_Off (F_Type)
2525 and then not Has_Size_Clause (F_Type)
2528 ("?& is an 8-bit Ada Boolean, "
2529 & "use char in C!", Formal);
2531 -- Check suspicious tagged type
2533 elsif (Is_Tagged_Type (F_Type)
2534 or else (Is_Access_Type (F_Type)
2537 (Designated_Type (F_Type))))
2538 and then Convention (E) = Convention_C
2541 ("?& involves a tagged type which does not "
2542 & "correspond to any C type!", Formal);
2544 -- Check wrong convention subprogram pointer
2546 elsif Ekind (F_Type) = E_Access_Subprogram_Type
2547 and then not Has_Foreign_Convention (F_Type)
2550 ("?subprogram pointer & should "
2551 & "have foreign convention!", Formal);
2552 Error_Msg_Sloc := Sloc (F_Type);
2554 ("\?add Convention pragma to declaration of &#",
2558 Error_Msg_Qual_Level := 0;
2561 -- Check for unconstrained array in exported foreign
2564 if Has_Foreign_Convention (E)
2565 and then not Is_Imported (E)
2566 and then Is_Array_Type (F_Type)
2567 and then not Is_Constrained (F_Type)
2568 and then Warn_On_Export_Import
2570 Error_Msg_Qual_Level := 1;
2572 -- If this is an inherited operation, place the
2573 -- warning on the derived type declaration, rather
2574 -- than on the original subprogram.
2576 if Nkind (Original_Node (Parent (E))) =
2577 N_Full_Type_Declaration
2579 Warn_Node := Parent (E);
2581 if Formal = First_Formal (E) then
2583 ("?in inherited operation&", Warn_Node, E);
2586 Warn_Node := Formal;
2590 ("?type of argument& is unconstrained array",
2593 ("?foreign caller must pass bounds explicitly",
2595 Error_Msg_Qual_Level := 0;
2598 if not From_With_Type (F_Type) then
2599 if Is_Access_Type (F_Type) then
2600 F_Type := Designated_Type (F_Type);
2603 -- If the formal is an anonymous_access_to_subprogram
2604 -- freeze the subprogram type as well, to prevent
2605 -- scope anomalies in gigi, because there is no other
2606 -- clear point at which it could be frozen.
2608 if Is_Itype (Etype (Formal))
2609 and then Ekind (F_Type) = E_Subprogram_Type
2611 Freeze_And_Append (F_Type, Loc, Result);
2615 Next_Formal (Formal);
2618 -- Case of function: similar checks on return type
2620 if Ekind (E) = E_Function then
2622 -- Freeze return type
2624 R_Type := Etype (E);
2625 Freeze_And_Append (R_Type, Loc, Result);
2627 -- Check suspicious return type for C function
2629 if Warn_On_Export_Import
2630 and then (Convention (E) = Convention_C
2632 Convention (E) = Convention_CPP)
2633 and then (Is_Imported (E) or else Is_Exported (E))
2635 -- Check suspicious return of fat C pointer
2637 if Is_Access_Type (R_Type)
2638 and then Esize (R_Type) > Ttypes.System_Address_Size
2639 and then not Has_Warnings_Off (E)
2640 and then not Has_Warnings_Off (R_Type)
2643 ("?return type of& does not "
2644 & "correspond to C pointer!", E);
2646 -- Check suspicious return of boolean
2648 elsif Root_Type (R_Type) = Standard_Boolean
2649 and then Convention (R_Type) = Convention_Ada
2650 and then not Has_Warnings_Off (E)
2651 and then not Has_Warnings_Off (R_Type)
2652 and then not Has_Size_Clause (R_Type)
2655 ("?return type of & is an 8-bit "
2656 & "Ada Boolean, use char in C!", E);
2658 -- Check suspicious return tagged type
2660 elsif (Is_Tagged_Type (R_Type)
2661 or else (Is_Access_Type (R_Type)
2664 (Designated_Type (R_Type))))
2665 and then Convention (E) = Convention_C
2666 and then not Has_Warnings_Off (E)
2667 and then not Has_Warnings_Off (R_Type)
2670 ("?return type of & does not "
2671 & "correspond to C type!", E);
2673 -- Check return of wrong convention subprogram pointer
2675 elsif Ekind (R_Type) = E_Access_Subprogram_Type
2676 and then not Has_Foreign_Convention (R_Type)
2677 and then not Has_Warnings_Off (E)
2678 and then not Has_Warnings_Off (R_Type)
2681 ("?& should return a foreign "
2682 & "convention subprogram pointer", E);
2683 Error_Msg_Sloc := Sloc (R_Type);
2685 ("\?add Convention pragma to declaration of& #",
2690 -- Give warning for suspicous return of a result of an
2691 -- unconstrained array type in a foreign convention
2694 if Has_Foreign_Convention (E)
2696 -- We are looking for a return of unconstrained array
2698 and then Is_Array_Type (R_Type)
2699 and then not Is_Constrained (R_Type)
2701 -- Exclude imported routines, the warning does not
2702 -- belong on the import, but on the routine definition.
2704 and then not Is_Imported (E)
2706 -- Exclude VM case, since both .NET and JVM can handle
2707 -- return of unconstrained arrays without a problem.
2709 and then VM_Target = No_VM
2711 -- Check that general warning is enabled, and that it
2712 -- is not suppressed for this particular case.
2714 and then Warn_On_Export_Import
2715 and then not Has_Warnings_Off (E)
2716 and then not Has_Warnings_Off (R_Type)
2719 ("?foreign convention function& should not " &
2720 "return unconstrained array!", E);
2726 -- Must freeze its parent first if it is a derived subprogram
2728 if Present (Alias (E)) then
2729 Freeze_And_Append (Alias (E), Loc, Result);
2732 -- We don't freeze internal subprograms, because we don't normally
2733 -- want addition of extra formals or mechanism setting to happen
2734 -- for those. However we do pass through predefined dispatching
2735 -- cases, since extra formals may be needed in some cases, such as
2736 -- for the stream 'Input function (build-in-place formals).
2738 if not Is_Internal (E)
2739 or else Is_Predefined_Dispatching_Operation (E)
2741 Freeze_Subprogram (E);
2744 -- Here for other than a subprogram or type
2747 -- If entity has a type, and it is not a generic unit, then
2748 -- freeze it first (RM 13.14(10)).
2750 if Present (Etype (E))
2751 and then Ekind (E) /= E_Generic_Function
2753 Freeze_And_Append (Etype (E), Loc, Result);
2756 -- Special processing for objects created by object declaration
2758 if Nkind (Declaration_Node (E)) = N_Object_Declaration then
2760 -- Abstract type allowed only for C++ imported variables or
2763 -- Note: we inhibit this check for objects that do not come
2764 -- from source because there is at least one case (the
2765 -- expansion of x'class'input where x is abstract) where we
2766 -- legitimately generate an abstract object.
2768 if Is_Abstract_Type (Etype (E))
2769 and then Comes_From_Source (Parent (E))
2770 and then not (Is_Imported (E)
2771 and then Is_CPP_Class (Etype (E)))
2773 Error_Msg_N ("type of object cannot be abstract",
2774 Object_Definition (Parent (E)));
2776 if Is_CPP_Class (Etype (E)) then
2777 Error_Msg_NE ("\} may need a cpp_constructor",
2778 Object_Definition (Parent (E)), Etype (E));
2782 -- For object created by object declaration, perform required
2783 -- categorization (preelaborate and pure) checks. Defer these
2784 -- checks to freeze time since pragma Import inhibits default
2785 -- initialization and thus pragma Import affects these checks.
2787 Validate_Object_Declaration (Declaration_Node (E));
2789 -- If there is an address clause, check that it is valid
2791 Check_Address_Clause (E);
2793 -- If the object needs any kind of default initialization, an
2794 -- error must be issued if No_Default_Initialization applies.
2795 -- The check doesn't apply to imported objects, which are not
2796 -- ever default initialized, and is why the check is deferred
2797 -- until freezing, at which point we know if Import applies.
2798 -- Deferred constants are also exempted from this test because
2799 -- their completion is explicit, or through an import pragma.
2801 if Ekind (E) = E_Constant
2802 and then Present (Full_View (E))
2806 elsif Comes_From_Source (E)
2807 and then not Is_Imported (E)
2808 and then not Has_Init_Expression (Declaration_Node (E))
2810 ((Has_Non_Null_Base_Init_Proc (Etype (E))
2811 and then not No_Initialization (Declaration_Node (E))
2812 and then not Is_Value_Type (Etype (E))
2813 and then not Suppress_Init_Proc (Etype (E)))
2815 (Needs_Simple_Initialization (Etype (E))
2816 and then not Is_Internal (E)))
2818 Has_Default_Initialization := True;
2820 (No_Default_Initialization, Declaration_Node (E));
2823 -- Check that a Thread_Local_Storage variable does not have
2824 -- default initialization, and any explicit initialization must
2825 -- either be the null constant or a static constant.
2827 if Has_Pragma_Thread_Local_Storage (E) then
2829 Decl : constant Node_Id := Declaration_Node (E);
2831 if Has_Default_Initialization
2833 (Has_Init_Expression (Decl)
2835 (No (Expression (Decl))
2837 (Is_Static_Expression (Expression (Decl))
2839 Nkind (Expression (Decl)) = N_Null)))
2842 ("Thread_Local_Storage variable& is "
2843 & "improperly initialized", Decl, E);
2845 ("\only allowed initialization is explicit "
2846 & "NULL or static expression", Decl, E);
2851 -- For imported objects, set Is_Public unless there is also an
2852 -- address clause, which means that there is no external symbol
2853 -- needed for the Import (Is_Public may still be set for other
2854 -- unrelated reasons). Note that we delayed this processing
2855 -- till freeze time so that we can be sure not to set the flag
2856 -- if there is an address clause. If there is such a clause,
2857 -- then the only purpose of the Import pragma is to suppress
2858 -- implicit initialization.
2861 and then No (Address_Clause (E))
2866 -- For convention C objects of an enumeration type, warn if
2867 -- the size is not integer size and no explicit size given.
2868 -- Skip warning for Boolean, and Character, assume programmer
2869 -- expects 8-bit sizes for these cases.
2871 if (Convention (E) = Convention_C
2873 Convention (E) = Convention_CPP)
2874 and then Is_Enumeration_Type (Etype (E))
2875 and then not Is_Character_Type (Etype (E))
2876 and then not Is_Boolean_Type (Etype (E))
2877 and then Esize (Etype (E)) < Standard_Integer_Size
2878 and then not Has_Size_Clause (E)
2880 Error_Msg_Uint_1 := UI_From_Int (Standard_Integer_Size);
2882 ("?convention C enumeration object has size less than ^",
2884 Error_Msg_N ("\?use explicit size clause to set size", E);
2888 -- Check that a constant which has a pragma Volatile[_Components]
2889 -- or Atomic[_Components] also has a pragma Import (RM C.6(13)).
2891 -- Note: Atomic[_Components] also sets Volatile[_Components]
2893 if Ekind (E) = E_Constant
2894 and then (Has_Volatile_Components (E) or else Is_Volatile (E))
2895 and then not Is_Imported (E)
2897 -- Make sure we actually have a pragma, and have not merely
2898 -- inherited the indication from elsewhere (e.g. an address
2899 -- clause, which is not good enough in RM terms!)
2901 if Has_Rep_Pragma (E, Name_Atomic)
2903 Has_Rep_Pragma (E, Name_Atomic_Components)
2906 ("stand alone atomic constant must be " &
2907 "imported (RM C.6(13))", E);
2909 elsif Has_Rep_Pragma (E, Name_Volatile)
2911 Has_Rep_Pragma (E, Name_Volatile_Components)
2914 ("stand alone volatile constant must be " &
2915 "imported (RM C.6(13))", E);
2919 -- Static objects require special handling
2921 if (Ekind (E) = E_Constant or else Ekind (E) = E_Variable)
2922 and then Is_Statically_Allocated (E)
2924 Freeze_Static_Object (E);
2927 -- Remaining step is to layout objects
2929 if Ekind (E) = E_Variable
2931 Ekind (E) = E_Constant
2933 Ekind (E) = E_Loop_Parameter
2941 -- Case of a type or subtype being frozen
2944 -- We used to check here that a full type must have preelaborable
2945 -- initialization if it completes a private type specified with
2946 -- pragma Preelaborable_Intialization, but that missed cases where
2947 -- the types occur within a generic package, since the freezing
2948 -- that occurs within a containing scope generally skips traversal
2949 -- of a generic unit's declarations (those will be frozen within
2950 -- instances). This check was moved to Analyze_Package_Specification.
2952 -- The type may be defined in a generic unit. This can occur when
2953 -- freezing a generic function that returns the type (which is
2954 -- defined in a parent unit). It is clearly meaningless to freeze
2955 -- this type. However, if it is a subtype, its size may be determi-
2956 -- nable and used in subsequent checks, so might as well try to
2959 if Present (Scope (E))
2960 and then Is_Generic_Unit (Scope (E))
2962 Check_Compile_Time_Size (E);
2966 -- Deal with special cases of freezing for subtype
2968 if E /= Base_Type (E) then
2970 -- Before we do anything else, a specialized test for the case of
2971 -- a size given for an array where the array needs to be packed,
2972 -- but was not so the size cannot be honored. This would of course
2973 -- be caught by the backend, and indeed we don't catch all cases.
2974 -- The point is that we can give a better error message in those
2975 -- cases that we do catch with the circuitry here. Also if pragma
2976 -- Implicit_Packing is set, this is where the packing occurs.
2978 -- The reason we do this so early is that the processing in the
2979 -- automatic packing case affects the layout of the base type, so
2980 -- it must be done before we freeze the base type.
2982 if Is_Array_Type (E) then
2985 Ctyp : constant Entity_Id := Component_Type (E);
2988 -- Check enabling conditions. These are straightforward
2989 -- except for the test for a limited composite type. This
2990 -- eliminates the rare case of a array of limited components
2991 -- where there are issues of whether or not we can go ahead
2992 -- and pack the array (since we can't freely pack and unpack
2993 -- arrays if they are limited).
2995 -- Note that we check the root type explicitly because the
2996 -- whole point is we are doing this test before we have had
2997 -- a chance to freeze the base type (and it is that freeze
2998 -- action that causes stuff to be inherited).
3000 if Present (Size_Clause (E))
3001 and then Known_Static_Esize (E)
3002 and then not Is_Packed (E)
3003 and then not Has_Pragma_Pack (E)
3004 and then Number_Dimensions (E) = 1
3005 and then not Has_Component_Size_Clause (E)
3006 and then Known_Static_Esize (Ctyp)
3007 and then not Is_Limited_Composite (E)
3008 and then not Is_Packed (Root_Type (E))
3009 and then not Has_Component_Size_Clause (Root_Type (E))
3011 Get_Index_Bounds (First_Index (E), Lo, Hi);
3013 if Compile_Time_Known_Value (Lo)
3014 and then Compile_Time_Known_Value (Hi)
3015 and then Known_Static_RM_Size (Ctyp)
3016 and then RM_Size (Ctyp) < 64
3019 Lov : constant Uint := Expr_Value (Lo);
3020 Hiv : constant Uint := Expr_Value (Hi);
3021 Len : constant Uint := UI_Max
3024 Rsiz : constant Uint := RM_Size (Ctyp);
3025 SZ : constant Node_Id := Size_Clause (E);
3026 Btyp : constant Entity_Id := Base_Type (E);
3028 -- What we are looking for here is the situation where
3029 -- the RM_Size given would be exactly right if there
3030 -- was a pragma Pack (resulting in the component size
3031 -- being the same as the RM_Size). Furthermore, the
3032 -- component type size must be an odd size (not a
3033 -- multiple of storage unit)
3036 if RM_Size (E) = Len * Rsiz
3037 and then Rsiz mod System_Storage_Unit /= 0
3039 -- For implicit packing mode, just set the
3040 -- component size silently.
3042 if Implicit_Packing then
3043 Set_Component_Size (Btyp, Rsiz);
3044 Set_Is_Bit_Packed_Array (Btyp);
3045 Set_Is_Packed (Btyp);
3046 Set_Has_Non_Standard_Rep (Btyp);
3048 -- Otherwise give an error message
3052 ("size given for& too small", SZ, E);
3054 ("\use explicit pragma Pack "
3055 & "or use pragma Implicit_Packing", SZ);
3064 -- If ancestor subtype present, freeze that first. Note that this
3065 -- will also get the base type frozen.
3067 Atype := Ancestor_Subtype (E);
3069 if Present (Atype) then
3070 Freeze_And_Append (Atype, Loc, Result);
3072 -- Otherwise freeze the base type of the entity before freezing
3073 -- the entity itself (RM 13.14(15)).
3075 elsif E /= Base_Type (E) then
3076 Freeze_And_Append (Base_Type (E), Loc, Result);
3079 -- For a derived type, freeze its parent type first (RM 13.14(15))
3081 elsif Is_Derived_Type (E) then
3082 Freeze_And_Append (Etype (E), Loc, Result);
3083 Freeze_And_Append (First_Subtype (Etype (E)), Loc, Result);
3086 -- For array type, freeze index types and component type first
3087 -- before freezing the array (RM 13.14(15)).
3089 if Is_Array_Type (E) then
3091 Ctyp : constant Entity_Id := Component_Type (E);
3093 Non_Standard_Enum : Boolean := False;
3094 -- Set true if any of the index types is an enumeration type
3095 -- with a non-standard representation.
3098 Freeze_And_Append (Ctyp, Loc, Result);
3100 Indx := First_Index (E);
3101 while Present (Indx) loop
3102 Freeze_And_Append (Etype (Indx), Loc, Result);
3104 if Is_Enumeration_Type (Etype (Indx))
3105 and then Has_Non_Standard_Rep (Etype (Indx))
3107 Non_Standard_Enum := True;
3113 -- Processing that is done only for base types
3115 if Ekind (E) = E_Array_Type then
3117 -- Propagate flags for component type
3119 if Is_Controlled (Component_Type (E))
3120 or else Has_Controlled_Component (Ctyp)
3122 Set_Has_Controlled_Component (E);
3125 if Has_Unchecked_Union (Component_Type (E)) then
3126 Set_Has_Unchecked_Union (E);
3129 -- If packing was requested or if the component size was set
3130 -- explicitly, then see if bit packing is required. This
3131 -- processing is only done for base types, since all the
3132 -- representation aspects involved are type-related. This
3133 -- is not just an optimization, if we start processing the
3134 -- subtypes, they interfere with the settings on the base
3135 -- type (this is because Is_Packed has a slightly different
3136 -- meaning before and after freezing).
3143 if (Is_Packed (E) or else Has_Pragma_Pack (E))
3144 and then not Has_Atomic_Components (E)
3145 and then Known_Static_RM_Size (Ctyp)
3147 Csiz := UI_Max (RM_Size (Ctyp), 1);
3149 elsif Known_Component_Size (E) then
3150 Csiz := Component_Size (E);
3152 elsif not Known_Static_Esize (Ctyp) then
3156 Esiz := Esize (Ctyp);
3158 -- We can set the component size if it is less than
3159 -- 16, rounding it up to the next storage unit size.
3163 elsif Esiz <= 16 then
3169 -- Set component size up to match alignment if it
3170 -- would otherwise be less than the alignment. This
3171 -- deals with cases of types whose alignment exceeds
3172 -- their size (padded types).
3176 A : constant Uint := Alignment_In_Bits (Ctyp);
3185 -- Case of component size that may result in packing
3187 if 1 <= Csiz and then Csiz <= 64 then
3189 Ent : constant Entity_Id :=
3191 Pack_Pragma : constant Node_Id :=
3192 Get_Rep_Pragma (Ent, Name_Pack);
3193 Comp_Size_C : constant Node_Id :=
3194 Get_Attribute_Definition_Clause
3195 (Ent, Attribute_Component_Size);
3197 -- Warn if we have pack and component size so that
3198 -- the pack is ignored.
3200 -- Note: here we must check for the presence of a
3201 -- component size before checking for a Pack pragma
3202 -- to deal with the case where the array type is a
3203 -- derived type whose parent is currently private.
3205 if Present (Comp_Size_C)
3206 and then Has_Pragma_Pack (Ent)
3208 Error_Msg_Sloc := Sloc (Comp_Size_C);
3210 ("?pragma Pack for& ignored!",
3213 ("\?explicit component size given#!",
3217 -- Set component size if not already set by a
3218 -- component size clause.
3220 if not Present (Comp_Size_C) then
3221 Set_Component_Size (E, Csiz);
3224 -- Check for base type of 8, 16, 32 bits, where an
3225 -- unsigned subtype has a length one less than the
3226 -- base type (e.g. Natural subtype of Integer).
3228 -- In such cases, if a component size was not set
3229 -- explicitly, then generate a warning.
3231 if Has_Pragma_Pack (E)
3232 and then not Present (Comp_Size_C)
3234 (Csiz = 7 or else Csiz = 15 or else Csiz = 31)
3235 and then Esize (Base_Type (Ctyp)) = Csiz + 1
3237 Error_Msg_Uint_1 := Csiz;
3239 if Present (Pack_Pragma) then
3241 ("?pragma Pack causes component size "
3242 & "to be ^!", Pack_Pragma);
3244 ("\?use Component_Size to set "
3245 & "desired value!", Pack_Pragma);
3249 -- Actual packing is not needed for 8, 16, 32, 64.
3250 -- Also not needed for 24 if alignment is 1.
3256 or else (Csiz = 24 and then Alignment (Ctyp) = 1)
3258 -- Here the array was requested to be packed,
3259 -- but the packing request had no effect, so
3260 -- Is_Packed is reset.
3262 -- Note: semantically this means that we lose
3263 -- track of the fact that a derived type
3264 -- inherited a pragma Pack that was non-
3265 -- effective, but that seems fine.
3267 -- We regard a Pack pragma as a request to set
3268 -- a representation characteristic, and this
3269 -- request may be ignored.
3271 Set_Is_Packed (Base_Type (E), False);
3273 -- In all other cases, packing is indeed needed
3276 Set_Has_Non_Standard_Rep (Base_Type (E));
3277 Set_Is_Bit_Packed_Array (Base_Type (E));
3278 Set_Is_Packed (Base_Type (E));
3284 -- Processing that is done only for subtypes
3287 -- Acquire alignment from base type
3289 if Unknown_Alignment (E) then
3290 Set_Alignment (E, Alignment (Base_Type (E)));
3291 Adjust_Esize_Alignment (E);
3295 -- For bit-packed arrays, check the size
3297 if Is_Bit_Packed_Array (E)
3298 and then Known_RM_Size (E)
3301 SizC : constant Node_Id := Size_Clause (E);
3304 pragma Warnings (Off, Discard);
3307 -- It is not clear if it is possible to have no size
3308 -- clause at this stage, but it is not worth worrying
3309 -- about. Post error on the entity name in the size
3310 -- clause if present, else on the type entity itself.
3312 if Present (SizC) then
3313 Check_Size (Name (SizC), E, RM_Size (E), Discard);
3315 Check_Size (E, E, RM_Size (E), Discard);
3320 -- If any of the index types was an enumeration type with
3321 -- a non-standard rep clause, then we indicate that the
3322 -- array type is always packed (even if it is not bit packed).
3324 if Non_Standard_Enum then
3325 Set_Has_Non_Standard_Rep (Base_Type (E));
3326 Set_Is_Packed (Base_Type (E));
3329 Set_Component_Alignment_If_Not_Set (E);
3331 -- If the array is packed, we must create the packed array
3332 -- type to be used to actually implement the type. This is
3333 -- only needed for real array types (not for string literal
3334 -- types, since they are present only for the front end).
3337 and then Ekind (E) /= E_String_Literal_Subtype
3339 Create_Packed_Array_Type (E);
3340 Freeze_And_Append (Packed_Array_Type (E), Loc, Result);
3342 -- Size information of packed array type is copied to the
3343 -- array type, since this is really the representation. But
3344 -- do not override explicit existing size values. If the
3345 -- ancestor subtype is constrained the packed_array_type
3346 -- will be inherited from it, but the size may have been
3347 -- provided already, and must not be overridden either.
3349 if not Has_Size_Clause (E)
3351 (No (Ancestor_Subtype (E))
3352 or else not Has_Size_Clause (Ancestor_Subtype (E)))
3354 Set_Esize (E, Esize (Packed_Array_Type (E)));
3355 Set_RM_Size (E, RM_Size (Packed_Array_Type (E)));
3358 if not Has_Alignment_Clause (E) then
3359 Set_Alignment (E, Alignment (Packed_Array_Type (E)));
3363 -- For non-packed arrays set the alignment of the array to the
3364 -- alignment of the component type if it is unknown. Skip this
3365 -- in atomic case (atomic arrays may need larger alignments).
3367 if not Is_Packed (E)
3368 and then Unknown_Alignment (E)
3369 and then Known_Alignment (Ctyp)
3370 and then Known_Static_Component_Size (E)
3371 and then Known_Static_Esize (Ctyp)
3372 and then Esize (Ctyp) = Component_Size (E)
3373 and then not Is_Atomic (E)
3375 Set_Alignment (E, Alignment (Component_Type (E)));
3379 -- For a class-wide type, the corresponding specific type is
3380 -- frozen as well (RM 13.14(15))
3382 elsif Is_Class_Wide_Type (E) then
3383 Freeze_And_Append (Root_Type (E), Loc, Result);
3385 -- If the base type of the class-wide type is still incomplete,
3386 -- the class-wide remains unfrozen as well. This is legal when
3387 -- E is the formal of a primitive operation of some other type
3388 -- which is being frozen.
3390 if not Is_Frozen (Root_Type (E)) then
3391 Set_Is_Frozen (E, False);
3395 -- If the Class_Wide_Type is an Itype (when type is the anonymous
3396 -- parent of a derived type) and it is a library-level entity,
3397 -- generate an itype reference for it. Otherwise, its first
3398 -- explicit reference may be in an inner scope, which will be
3399 -- rejected by the back-end.
3402 and then Is_Compilation_Unit (Scope (E))
3405 Ref : constant Node_Id := Make_Itype_Reference (Loc);
3410 Result := New_List (Ref);
3412 Append (Ref, Result);
3417 -- The equivalent type associated with a class-wide subtype needs
3418 -- to be frozen to ensure that its layout is done. Class-wide
3419 -- subtypes are currently only frozen on targets requiring
3420 -- front-end layout (see New_Class_Wide_Subtype and
3421 -- Make_CW_Equivalent_Type in exp_util.adb).
3423 if Ekind (E) = E_Class_Wide_Subtype
3424 and then Present (Equivalent_Type (E))
3426 Freeze_And_Append (Equivalent_Type (E), Loc, Result);
3429 -- For a record (sub)type, freeze all the component types (RM
3430 -- 13.14(15). We test for E_Record_(sub)Type here, rather than using
3431 -- Is_Record_Type, because we don't want to attempt the freeze for
3432 -- the case of a private type with record extension (we will do that
3433 -- later when the full type is frozen).
3435 elsif Ekind (E) = E_Record_Type
3436 or else Ekind (E) = E_Record_Subtype
3438 Freeze_Record_Type (E);
3440 -- For a concurrent type, freeze corresponding record type. This
3441 -- does not correspond to any specific rule in the RM, but the
3442 -- record type is essentially part of the concurrent type.
3443 -- Freeze as well all local entities. This includes record types
3444 -- created for entry parameter blocks, and whatever local entities
3445 -- may appear in the private part.
3447 elsif Is_Concurrent_Type (E) then
3448 if Present (Corresponding_Record_Type (E)) then
3450 (Corresponding_Record_Type (E), Loc, Result);
3453 Comp := First_Entity (E);
3454 while Present (Comp) loop
3455 if Is_Type (Comp) then
3456 Freeze_And_Append (Comp, Loc, Result);
3458 elsif (Ekind (Comp)) /= E_Function then
3459 if Is_Itype (Etype (Comp))
3460 and then Underlying_Type (Scope (Etype (Comp))) = E
3462 Undelay_Type (Etype (Comp));
3465 Freeze_And_Append (Etype (Comp), Loc, Result);
3471 -- Private types are required to point to the same freeze node as
3472 -- their corresponding full views. The freeze node itself has to
3473 -- point to the partial view of the entity (because from the partial
3474 -- view, we can retrieve the full view, but not the reverse).
3475 -- However, in order to freeze correctly, we need to freeze the full
3476 -- view. If we are freezing at the end of a scope (or within the
3477 -- scope of the private type), the partial and full views will have
3478 -- been swapped, the full view appears first in the entity chain and
3479 -- the swapping mechanism ensures that the pointers are properly set
3482 -- If we encounter the partial view before the full view (e.g. when
3483 -- freezing from another scope), we freeze the full view, and then
3484 -- set the pointers appropriately since we cannot rely on swapping to
3485 -- fix things up (subtypes in an outer scope might not get swapped).
3487 elsif Is_Incomplete_Or_Private_Type (E)
3488 and then not Is_Generic_Type (E)
3490 -- The construction of the dispatch table associated with library
3491 -- level tagged types forces freezing of all the primitives of the
3492 -- type, which may cause premature freezing of the partial view.
3496 -- type T is tagged private;
3497 -- type DT is new T with private;
3498 -- procedure Prim (X : in out T; Y : in out DT'class);
3500 -- type T is tagged null record;
3502 -- type DT is new T with null record;
3505 -- In this case the type will be frozen later by the usual
3506 -- mechanism: an object declaration, an instantiation, or the
3507 -- end of a declarative part.
3509 if Is_Library_Level_Tagged_Type (E)
3510 and then not Present (Full_View (E))
3512 Set_Is_Frozen (E, False);
3515 -- Case of full view present
3517 elsif Present (Full_View (E)) then
3519 -- If full view has already been frozen, then no further
3520 -- processing is required
3522 if Is_Frozen (Full_View (E)) then
3524 Set_Has_Delayed_Freeze (E, False);
3525 Set_Freeze_Node (E, Empty);
3526 Check_Debug_Info_Needed (E);
3528 -- Otherwise freeze full view and patch the pointers so that
3529 -- the freeze node will elaborate both views in the back-end.
3533 Full : constant Entity_Id := Full_View (E);
3536 if Is_Private_Type (Full)
3537 and then Present (Underlying_Full_View (Full))
3540 (Underlying_Full_View (Full), Loc, Result);
3543 Freeze_And_Append (Full, Loc, Result);
3545 if Has_Delayed_Freeze (E) then
3546 F_Node := Freeze_Node (Full);
3548 if Present (F_Node) then
3549 Set_Freeze_Node (E, F_Node);
3550 Set_Entity (F_Node, E);
3553 -- {Incomplete,Private}_Subtypes with Full_Views
3554 -- constrained by discriminants.
3556 Set_Has_Delayed_Freeze (E, False);
3557 Set_Freeze_Node (E, Empty);
3562 Check_Debug_Info_Needed (E);
3565 -- AI-117 requires that the convention of a partial view be the
3566 -- same as the convention of the full view. Note that this is a
3567 -- recognized breach of privacy, but it's essential for logical
3568 -- consistency of representation, and the lack of a rule in
3569 -- RM95 was an oversight.
3571 Set_Convention (E, Convention (Full_View (E)));
3573 Set_Size_Known_At_Compile_Time (E,
3574 Size_Known_At_Compile_Time (Full_View (E)));
3576 -- Size information is copied from the full view to the
3577 -- incomplete or private view for consistency.
3579 -- We skip this is the full view is not a type. This is very
3580 -- strange of course, and can only happen as a result of
3581 -- certain illegalities, such as a premature attempt to derive
3582 -- from an incomplete type.
3584 if Is_Type (Full_View (E)) then
3585 Set_Size_Info (E, Full_View (E));
3586 Set_RM_Size (E, RM_Size (Full_View (E)));
3591 -- Case of no full view present. If entity is derived or subtype,
3592 -- it is safe to freeze, correctness depends on the frozen status
3593 -- of parent. Otherwise it is either premature usage, or a Taft
3594 -- amendment type, so diagnosis is at the point of use and the
3595 -- type might be frozen later.
3597 elsif E /= Base_Type (E)
3598 or else Is_Derived_Type (E)
3603 Set_Is_Frozen (E, False);
3607 -- For access subprogram, freeze types of all formals, the return
3608 -- type was already frozen, since it is the Etype of the function.
3609 -- Formal types can be tagged Taft amendment types, but otherwise
3610 -- they cannot be incomplete.
3612 elsif Ekind (E) = E_Subprogram_Type then
3613 Formal := First_Formal (E);
3615 while Present (Formal) loop
3616 if Ekind (Etype (Formal)) = E_Incomplete_Type
3617 and then No (Full_View (Etype (Formal)))
3618 and then not Is_Value_Type (Etype (Formal))
3620 if Is_Tagged_Type (Etype (Formal)) then
3624 ("invalid use of incomplete type&", E, Etype (Formal));
3628 Freeze_And_Append (Etype (Formal), Loc, Result);
3629 Next_Formal (Formal);
3632 Freeze_Subprogram (E);
3634 -- For access to a protected subprogram, freeze the equivalent type
3635 -- (however this is not set if we are not generating code or if this
3636 -- is an anonymous type used just for resolution).
3638 elsif Is_Access_Protected_Subprogram_Type (E) then
3639 if Present (Equivalent_Type (E)) then
3640 Freeze_And_Append (Equivalent_Type (E), Loc, Result);
3644 -- Generic types are never seen by the back-end, and are also not
3645 -- processed by the expander (since the expander is turned off for
3646 -- generic processing), so we never need freeze nodes for them.
3648 if Is_Generic_Type (E) then
3652 -- Some special processing for non-generic types to complete
3653 -- representation details not known till the freeze point.
3655 if Is_Fixed_Point_Type (E) then
3656 Freeze_Fixed_Point_Type (E);
3658 -- Some error checks required for ordinary fixed-point type. Defer
3659 -- these till the freeze-point since we need the small and range
3660 -- values. We only do these checks for base types
3662 if Is_Ordinary_Fixed_Point_Type (E)
3663 and then E = Base_Type (E)
3665 if Small_Value (E) < Ureal_2_M_80 then
3666 Error_Msg_Name_1 := Name_Small;
3668 ("`&''%` too small, minimum allowed is 2.0'*'*(-80)", E);
3670 elsif Small_Value (E) > Ureal_2_80 then
3671 Error_Msg_Name_1 := Name_Small;
3673 ("`&''%` too large, maximum allowed is 2.0'*'*80", E);
3676 if Expr_Value_R (Type_Low_Bound (E)) < Ureal_M_10_36 then
3677 Error_Msg_Name_1 := Name_First;
3679 ("`&''%` too small, minimum allowed is -10.0'*'*36", E);
3682 if Expr_Value_R (Type_High_Bound (E)) > Ureal_10_36 then
3683 Error_Msg_Name_1 := Name_Last;
3685 ("`&''%` too large, maximum allowed is 10.0'*'*36", E);
3689 elsif Is_Enumeration_Type (E) then
3690 Freeze_Enumeration_Type (E);
3692 elsif Is_Integer_Type (E) then
3693 Adjust_Esize_For_Alignment (E);
3695 if Is_Modular_Integer_Type (E)
3696 and then Warn_On_Suspicious_Modulus_Value
3698 Check_Suspicious_Modulus (E);
3701 elsif Is_Access_Type (E) then
3703 -- Check restriction for standard storage pool
3705 if No (Associated_Storage_Pool (E)) then
3706 Check_Restriction (No_Standard_Storage_Pools, E);
3709 -- Deal with error message for pure access type. This is not an
3710 -- error in Ada 2005 if there is no pool (see AI-366).
3712 if Is_Pure_Unit_Access_Type (E)
3713 and then (Ada_Version < Ada_05
3714 or else not No_Pool_Assigned (E))
3716 Error_Msg_N ("named access type not allowed in pure unit", E);
3718 if Ada_Version >= Ada_05 then
3720 ("\would be legal if Storage_Size of 0 given?", E);
3722 elsif No_Pool_Assigned (E) then
3724 ("\would be legal in Ada 2005?", E);
3728 ("\would be legal in Ada 2005 if "
3729 & "Storage_Size of 0 given?", E);
3734 -- Case of composite types
3736 if Is_Composite_Type (E) then
3738 -- AI-117 requires that all new primitives of a tagged type must
3739 -- inherit the convention of the full view of the type. Inherited
3740 -- and overriding operations are defined to inherit the convention
3741 -- of their parent or overridden subprogram (also specified in
3742 -- AI-117), which will have occurred earlier (in Derive_Subprogram
3743 -- and New_Overloaded_Entity). Here we set the convention of
3744 -- primitives that are still convention Ada, which will ensure
3745 -- that any new primitives inherit the type's convention. Class-
3746 -- wide types can have a foreign convention inherited from their
3747 -- specific type, but are excluded from this since they don't have
3748 -- any associated primitives.
3750 if Is_Tagged_Type (E)
3751 and then not Is_Class_Wide_Type (E)
3752 and then Convention (E) /= Convention_Ada
3755 Prim_List : constant Elist_Id := Primitive_Operations (E);
3758 Prim := First_Elmt (Prim_List);
3759 while Present (Prim) loop
3760 if Convention (Node (Prim)) = Convention_Ada then
3761 Set_Convention (Node (Prim), Convention (E));
3770 -- Now that all types from which E may depend are frozen, see if the
3771 -- size is known at compile time, if it must be unsigned, or if
3772 -- strict alignment is required
3774 Check_Compile_Time_Size (E);
3775 Check_Unsigned_Type (E);
3777 if Base_Type (E) = E then
3778 Check_Strict_Alignment (E);
3781 -- Do not allow a size clause for a type which does not have a size
3782 -- that is known at compile time
3784 if Has_Size_Clause (E)
3785 and then not Size_Known_At_Compile_Time (E)
3787 -- Suppress this message if errors posted on E, even if we are
3788 -- in all errors mode, since this is often a junk message
3790 if not Error_Posted (E) then
3792 ("size clause not allowed for variable length type",
3797 -- Remaining process is to set/verify the representation information,
3798 -- in particular the size and alignment values. This processing is
3799 -- not required for generic types, since generic types do not play
3800 -- any part in code generation, and so the size and alignment values
3801 -- for such types are irrelevant.
3803 if Is_Generic_Type (E) then
3806 -- Otherwise we call the layout procedure
3812 -- End of freeze processing for type entities
3815 -- Here is where we logically freeze the current entity. If it has a
3816 -- freeze node, then this is the point at which the freeze node is
3817 -- linked into the result list.
3819 if Has_Delayed_Freeze (E) then
3821 -- If a freeze node is already allocated, use it, otherwise allocate
3822 -- a new one. The preallocation happens in the case of anonymous base
3823 -- types, where we preallocate so that we can set First_Subtype_Link.
3824 -- Note that we reset the Sloc to the current freeze location.
3826 if Present (Freeze_Node (E)) then
3827 F_Node := Freeze_Node (E);
3828 Set_Sloc (F_Node, Loc);
3831 F_Node := New_Node (N_Freeze_Entity, Loc);
3832 Set_Freeze_Node (E, F_Node);
3833 Set_Access_Types_To_Process (F_Node, No_Elist);
3834 Set_TSS_Elist (F_Node, No_Elist);
3835 Set_Actions (F_Node, No_List);
3838 Set_Entity (F_Node, E);
3840 if Result = No_List then
3841 Result := New_List (F_Node);
3843 Append (F_Node, Result);
3846 -- A final pass over record types with discriminants. If the type
3847 -- has an incomplete declaration, there may be constrained access
3848 -- subtypes declared elsewhere, which do not depend on the discrimi-
3849 -- nants of the type, and which are used as component types (i.e.
3850 -- the full view is a recursive type). The designated types of these
3851 -- subtypes can only be elaborated after the type itself, and they
3852 -- need an itype reference.
3854 if Ekind (E) = E_Record_Type
3855 and then Has_Discriminants (E)
3863 Comp := First_Component (E);
3865 while Present (Comp) loop
3866 Typ := Etype (Comp);
3868 if Ekind (Comp) = E_Component
3869 and then Is_Access_Type (Typ)
3870 and then Scope (Typ) /= E
3871 and then Base_Type (Designated_Type (Typ)) = E
3872 and then Is_Itype (Designated_Type (Typ))
3874 IR := Make_Itype_Reference (Sloc (Comp));
3875 Set_Itype (IR, Designated_Type (Typ));
3876 Append (IR, Result);
3879 Next_Component (Comp);
3885 -- When a type is frozen, the first subtype of the type is frozen as
3886 -- well (RM 13.14(15)). This has to be done after freezing the type,
3887 -- since obviously the first subtype depends on its own base type.
3890 Freeze_And_Append (First_Subtype (E), Loc, Result);
3892 -- If we just froze a tagged non-class wide record, then freeze the
3893 -- corresponding class-wide type. This must be done after the tagged
3894 -- type itself is frozen, because the class-wide type refers to the
3895 -- tagged type which generates the class.
3897 if Is_Tagged_Type (E)
3898 and then not Is_Class_Wide_Type (E)
3899 and then Present (Class_Wide_Type (E))
3901 Freeze_And_Append (Class_Wide_Type (E), Loc, Result);
3905 Check_Debug_Info_Needed (E);
3907 -- Special handling for subprograms
3909 if Is_Subprogram (E) then
3911 -- If subprogram has address clause then reset Is_Public flag, since
3912 -- we do not want the backend to generate external references.
3914 if Present (Address_Clause (E))
3915 and then not Is_Library_Level_Entity (E)
3917 Set_Is_Public (E, False);
3919 -- If no address clause and not intrinsic, then for imported
3920 -- subprogram in main unit, generate descriptor if we are in
3921 -- Propagate_Exceptions mode.
3923 elsif Propagate_Exceptions
3924 and then Is_Imported (E)
3925 and then not Is_Intrinsic_Subprogram (E)
3926 and then Convention (E) /= Convention_Stubbed
3928 if Result = No_List then
3929 Result := Empty_List;
3937 -----------------------------
3938 -- Freeze_Enumeration_Type --
3939 -----------------------------
3941 procedure Freeze_Enumeration_Type (Typ : Entity_Id) is
3943 -- By default, if no size clause is present, an enumeration type with
3944 -- Convention C is assumed to interface to a C enum, and has integer
3945 -- size. This applies to types. For subtypes, verify that its base
3946 -- type has no size clause either.
3948 if Has_Foreign_Convention (Typ)
3949 and then not Has_Size_Clause (Typ)
3950 and then not Has_Size_Clause (Base_Type (Typ))
3951 and then Esize (Typ) < Standard_Integer_Size
3953 Init_Esize (Typ, Standard_Integer_Size);
3956 -- If the enumeration type interfaces to C, and it has a size clause
3957 -- that specifies less than int size, it warrants a warning. The
3958 -- user may intend the C type to be an enum or a char, so this is
3959 -- not by itself an error that the Ada compiler can detect, but it
3960 -- it is a worth a heads-up. For Boolean and Character types we
3961 -- assume that the programmer has the proper C type in mind.
3963 if Convention (Typ) = Convention_C
3964 and then Has_Size_Clause (Typ)
3965 and then Esize (Typ) /= Esize (Standard_Integer)
3966 and then not Is_Boolean_Type (Typ)
3967 and then not Is_Character_Type (Typ)
3970 ("C enum types have the size of a C int?", Size_Clause (Typ));
3973 Adjust_Esize_For_Alignment (Typ);
3975 end Freeze_Enumeration_Type;
3977 -----------------------
3978 -- Freeze_Expression --
3979 -----------------------
3981 procedure Freeze_Expression (N : Node_Id) is
3982 In_Spec_Exp : constant Boolean := In_Spec_Expression;
3985 Desig_Typ : Entity_Id;
3989 Freeze_Outside : Boolean := False;
3990 -- This flag is set true if the entity must be frozen outside the
3991 -- current subprogram. This happens in the case of expander generated
3992 -- subprograms (_Init_Proc, _Input, _Output, _Read, _Write) which do
3993 -- not freeze all entities like other bodies, but which nevertheless
3994 -- may reference entities that have to be frozen before the body and
3995 -- obviously cannot be frozen inside the body.
3997 function In_Exp_Body (N : Node_Id) return Boolean;
3998 -- Given an N_Handled_Sequence_Of_Statements node N, determines whether
3999 -- it is the handled statement sequence of an expander-generated
4000 -- subprogram (init proc, stream subprogram, or renaming as body).
4001 -- If so, this is not a freezing context.
4007 function In_Exp_Body (N : Node_Id) return Boolean is
4012 if Nkind (N) = N_Subprogram_Body then
4018 if Nkind (P) /= N_Subprogram_Body then
4022 Id := Defining_Unit_Name (Specification (P));
4024 if Nkind (Id) = N_Defining_Identifier
4025 and then (Is_Init_Proc (Id) or else
4026 Is_TSS (Id, TSS_Stream_Input) or else
4027 Is_TSS (Id, TSS_Stream_Output) or else
4028 Is_TSS (Id, TSS_Stream_Read) or else
4029 Is_TSS (Id, TSS_Stream_Write) or else
4030 Nkind (Original_Node (P)) =
4031 N_Subprogram_Renaming_Declaration)
4040 -- Start of processing for Freeze_Expression
4043 -- Immediate return if freezing is inhibited. This flag is set by the
4044 -- analyzer to stop freezing on generated expressions that would cause
4045 -- freezing if they were in the source program, but which are not
4046 -- supposed to freeze, since they are created.
4048 if Must_Not_Freeze (N) then
4052 -- If expression is non-static, then it does not freeze in a default
4053 -- expression, see section "Handling of Default Expressions" in the
4054 -- spec of package Sem for further details. Note that we have to
4055 -- make sure that we actually have a real expression (if we have
4056 -- a subtype indication, we can't test Is_Static_Expression!)
4059 and then Nkind (N) in N_Subexpr
4060 and then not Is_Static_Expression (N)
4065 -- Freeze type of expression if not frozen already
4069 if Nkind (N) in N_Has_Etype then
4070 if not Is_Frozen (Etype (N)) then
4073 -- Base type may be an derived numeric type that is frozen at
4074 -- the point of declaration, but first_subtype is still unfrozen.
4076 elsif not Is_Frozen (First_Subtype (Etype (N))) then
4077 Typ := First_Subtype (Etype (N));
4081 -- For entity name, freeze entity if not frozen already. A special
4082 -- exception occurs for an identifier that did not come from source.
4083 -- We don't let such identifiers freeze a non-internal entity, i.e.
4084 -- an entity that did come from source, since such an identifier was
4085 -- generated by the expander, and cannot have any semantic effect on
4086 -- the freezing semantics. For example, this stops the parameter of
4087 -- an initialization procedure from freezing the variable.
4089 if Is_Entity_Name (N)
4090 and then not Is_Frozen (Entity (N))
4091 and then (Nkind (N) /= N_Identifier
4092 or else Comes_From_Source (N)
4093 or else not Comes_From_Source (Entity (N)))
4100 -- For an allocator freeze designated type if not frozen already
4102 -- For an aggregate whose component type is an access type, freeze the
4103 -- designated type now, so that its freeze does not appear within the
4104 -- loop that might be created in the expansion of the aggregate. If the
4105 -- designated type is a private type without full view, the expression
4106 -- cannot contain an allocator, so the type is not frozen.
4108 -- For a function, we freeze the entity when the subprogram declaration
4109 -- is frozen, but a function call may appear in an initialization proc.
4110 -- before the declaration is frozen. We need to generate the extra
4111 -- formals, if any, to ensure that the expansion of the call includes
4112 -- the proper actuals.
4118 Desig_Typ := Designated_Type (Etype (N));
4121 if Is_Array_Type (Etype (N))
4122 and then Is_Access_Type (Component_Type (Etype (N)))
4124 Desig_Typ := Designated_Type (Component_Type (Etype (N)));
4127 when N_Selected_Component |
4128 N_Indexed_Component |
4131 if Is_Access_Type (Etype (Prefix (N))) then
4132 Desig_Typ := Designated_Type (Etype (Prefix (N)));
4135 when N_Identifier =>
4137 and then Ekind (Nam) = E_Function
4138 and then Nkind (Parent (N)) = N_Function_Call
4140 Create_Extra_Formals (Nam);
4147 if Desig_Typ /= Empty
4148 and then (Is_Frozen (Desig_Typ)
4149 or else (not Is_Fully_Defined (Desig_Typ)))
4154 -- All done if nothing needs freezing
4158 and then No (Desig_Typ)
4163 -- Loop for looking at the right place to insert the freeze nodes,
4164 -- exiting from the loop when it is appropriate to insert the freeze
4165 -- node before the current node P.
4167 -- Also checks som special exceptions to the freezing rules. These cases
4168 -- result in a direct return, bypassing the freeze action.
4172 Parent_P := Parent (P);
4174 -- If we don't have a parent, then we are not in a well-formed tree.
4175 -- This is an unusual case, but there are some legitimate situations
4176 -- in which this occurs, notably when the expressions in the range of
4177 -- a type declaration are resolved. We simply ignore the freeze
4178 -- request in this case. Is this right ???
4180 if No (Parent_P) then
4184 -- See if we have got to an appropriate point in the tree
4186 case Nkind (Parent_P) is
4188 -- A special test for the exception of (RM 13.14(8)) for the case
4189 -- of per-object expressions (RM 3.8(18)) occurring in component
4190 -- definition or a discrete subtype definition. Note that we test
4191 -- for a component declaration which includes both cases we are
4192 -- interested in, and furthermore the tree does not have explicit
4193 -- nodes for either of these two constructs.
4195 when N_Component_Declaration =>
4197 -- The case we want to test for here is an identifier that is
4198 -- a per-object expression, this is either a discriminant that
4199 -- appears in a context other than the component declaration
4200 -- or it is a reference to the type of the enclosing construct.
4202 -- For either of these cases, we skip the freezing
4204 if not In_Spec_Expression
4205 and then Nkind (N) = N_Identifier
4206 and then (Present (Entity (N)))
4208 -- We recognize the discriminant case by just looking for
4209 -- a reference to a discriminant. It can only be one for
4210 -- the enclosing construct. Skip freezing in this case.
4212 if Ekind (Entity (N)) = E_Discriminant then
4215 -- For the case of a reference to the enclosing record,
4216 -- (or task or protected type), we look for a type that
4217 -- matches the current scope.
4219 elsif Entity (N) = Current_Scope then
4224 -- If we have an enumeration literal that appears as the choice in
4225 -- the aggregate of an enumeration representation clause, then
4226 -- freezing does not occur (RM 13.14(10)).
4228 when N_Enumeration_Representation_Clause =>
4230 -- The case we are looking for is an enumeration literal
4232 if (Nkind (N) = N_Identifier or Nkind (N) = N_Character_Literal)
4233 and then Is_Enumeration_Type (Etype (N))
4235 -- If enumeration literal appears directly as the choice,
4236 -- do not freeze (this is the normal non-overloaded case)
4238 if Nkind (Parent (N)) = N_Component_Association
4239 and then First (Choices (Parent (N))) = N
4243 -- If enumeration literal appears as the name of function
4244 -- which is the choice, then also do not freeze. This
4245 -- happens in the overloaded literal case, where the
4246 -- enumeration literal is temporarily changed to a function
4247 -- call for overloading analysis purposes.
4249 elsif Nkind (Parent (N)) = N_Function_Call
4251 Nkind (Parent (Parent (N))) = N_Component_Association
4253 First (Choices (Parent (Parent (N)))) = Parent (N)
4259 -- Normally if the parent is a handled sequence of statements,
4260 -- then the current node must be a statement, and that is an
4261 -- appropriate place to insert a freeze node.
4263 when N_Handled_Sequence_Of_Statements =>
4265 -- An exception occurs when the sequence of statements is for
4266 -- an expander generated body that did not do the usual freeze
4267 -- all operation. In this case we usually want to freeze
4268 -- outside this body, not inside it, and we skip past the
4269 -- subprogram body that we are inside.
4271 if In_Exp_Body (Parent_P) then
4273 -- However, we *do* want to freeze at this point if we have
4274 -- an entity to freeze, and that entity is declared *inside*
4275 -- the body of the expander generated procedure. This case
4276 -- is recognized by the scope of the type, which is either
4277 -- the spec for some enclosing body, or (in the case of
4278 -- init_procs, for which there are no separate specs) the
4282 Subp : constant Node_Id := Parent (Parent_P);
4286 if Nkind (Subp) = N_Subprogram_Body then
4287 Cspc := Corresponding_Spec (Subp);
4289 if (Present (Typ) and then Scope (Typ) = Cspc)
4291 (Present (Nam) and then Scope (Nam) = Cspc)
4296 and then Scope (Typ) = Current_Scope
4297 and then Current_Scope = Defining_Entity (Subp)
4304 -- If not that exception to the exception, then this is
4305 -- where we delay the freeze till outside the body.
4307 Parent_P := Parent (Parent_P);
4308 Freeze_Outside := True;
4310 -- Here if normal case where we are in handled statement
4311 -- sequence and want to do the insertion right there.
4317 -- If parent is a body or a spec or a block, then the current node
4318 -- is a statement or declaration and we can insert the freeze node
4321 when N_Package_Specification |
4327 N_Block_Statement => exit;
4329 -- The expander is allowed to define types in any statements list,
4330 -- so any of the following parent nodes also mark a freezing point
4331 -- if the actual node is in a list of statements or declarations.
4333 when N_Exception_Handler |
4336 N_Case_Statement_Alternative |
4337 N_Compilation_Unit_Aux |
4338 N_Selective_Accept |
4339 N_Accept_Alternative |
4340 N_Delay_Alternative |
4341 N_Conditional_Entry_Call |
4342 N_Entry_Call_Alternative |
4343 N_Triggering_Alternative |
4347 exit when Is_List_Member (P);
4349 -- Note: The N_Loop_Statement is a special case. A type that
4350 -- appears in the source can never be frozen in a loop (this
4351 -- occurs only because of a loop expanded by the expander), so we
4352 -- keep on going. Otherwise we terminate the search. Same is true
4353 -- of any entity which comes from source. (if they have predefined
4354 -- type, that type does not appear to come from source, but the
4355 -- entity should not be frozen here).
4357 when N_Loop_Statement =>
4358 exit when not Comes_From_Source (Etype (N))
4359 and then (No (Nam) or else not Comes_From_Source (Nam));
4361 -- For all other cases, keep looking at parents
4367 -- We fall through the case if we did not yet find the proper
4368 -- place in the free for inserting the freeze node, so climb!
4373 -- If the expression appears in a record or an initialization procedure,
4374 -- the freeze nodes are collected and attached to the current scope, to
4375 -- be inserted and analyzed on exit from the scope, to insure that
4376 -- generated entities appear in the correct scope. If the expression is
4377 -- a default for a discriminant specification, the scope is still void.
4378 -- The expression can also appear in the discriminant part of a private
4379 -- or concurrent type.
4381 -- If the expression appears in a constrained subcomponent of an
4382 -- enclosing record declaration, the freeze nodes must be attached to
4383 -- the outer record type so they can eventually be placed in the
4384 -- enclosing declaration list.
4386 -- The other case requiring this special handling is if we are in a
4387 -- default expression, since in that case we are about to freeze a
4388 -- static type, and the freeze scope needs to be the outer scope, not
4389 -- the scope of the subprogram with the default parameter.
4391 -- For default expressions and other spec expressions in generic units,
4392 -- the Move_Freeze_Nodes mechanism (see sem_ch12.adb) takes care of
4393 -- placing them at the proper place, after the generic unit.
4395 if (In_Spec_Exp and not Inside_A_Generic)
4396 or else Freeze_Outside
4397 or else (Is_Type (Current_Scope)
4398 and then (not Is_Concurrent_Type (Current_Scope)
4399 or else not Has_Completion (Current_Scope)))
4400 or else Ekind (Current_Scope) = E_Void
4403 Loc : constant Source_Ptr := Sloc (Current_Scope);
4404 Freeze_Nodes : List_Id := No_List;
4405 Pos : Int := Scope_Stack.Last;
4408 if Present (Desig_Typ) then
4409 Freeze_And_Append (Desig_Typ, Loc, Freeze_Nodes);
4412 if Present (Typ) then
4413 Freeze_And_Append (Typ, Loc, Freeze_Nodes);
4416 if Present (Nam) then
4417 Freeze_And_Append (Nam, Loc, Freeze_Nodes);
4420 -- The current scope may be that of a constrained component of
4421 -- an enclosing record declaration, which is above the current
4422 -- scope in the scope stack.
4424 if Is_Record_Type (Scope (Current_Scope)) then
4428 if Is_Non_Empty_List (Freeze_Nodes) then
4429 if No (Scope_Stack.Table (Pos).Pending_Freeze_Actions) then
4430 Scope_Stack.Table (Pos).Pending_Freeze_Actions :=
4433 Append_List (Freeze_Nodes, Scope_Stack.Table
4434 (Pos).Pending_Freeze_Actions);
4442 -- Now we have the right place to do the freezing. First, a special
4443 -- adjustment, if we are in spec-expression analysis mode, these freeze
4444 -- actions must not be thrown away (normally all inserted actions are
4445 -- thrown away in this mode. However, the freeze actions are from static
4446 -- expressions and one of the important reasons we are doing this
4447 -- special analysis is to get these freeze actions. Therefore we turn
4448 -- off the In_Spec_Expression mode to propagate these freeze actions.
4449 -- This also means they get properly analyzed and expanded.
4451 In_Spec_Expression := False;
4453 -- Freeze the designated type of an allocator (RM 13.14(13))
4455 if Present (Desig_Typ) then
4456 Freeze_Before (P, Desig_Typ);
4459 -- Freeze type of expression (RM 13.14(10)). Note that we took care of
4460 -- the enumeration representation clause exception in the loop above.
4462 if Present (Typ) then
4463 Freeze_Before (P, Typ);
4466 -- Freeze name if one is present (RM 13.14(11))
4468 if Present (Nam) then
4469 Freeze_Before (P, Nam);
4472 -- Restore In_Spec_Expression flag
4474 In_Spec_Expression := In_Spec_Exp;
4475 end Freeze_Expression;
4477 -----------------------------
4478 -- Freeze_Fixed_Point_Type --
4479 -----------------------------
4481 -- Certain fixed-point types and subtypes, including implicit base types
4482 -- and declared first subtypes, have not yet set up a range. This is
4483 -- because the range cannot be set until the Small and Size values are
4484 -- known, and these are not known till the type is frozen.
4486 -- To signal this case, Scalar_Range contains an unanalyzed syntactic range
4487 -- whose bounds are unanalyzed real literals. This routine will recognize
4488 -- this case, and transform this range node into a properly typed range
4489 -- with properly analyzed and resolved values.
4491 procedure Freeze_Fixed_Point_Type (Typ : Entity_Id) is
4492 Rng : constant Node_Id := Scalar_Range (Typ);
4493 Lo : constant Node_Id := Low_Bound (Rng);
4494 Hi : constant Node_Id := High_Bound (Rng);
4495 Btyp : constant Entity_Id := Base_Type (Typ);
4496 Brng : constant Node_Id := Scalar_Range (Btyp);
4497 BLo : constant Node_Id := Low_Bound (Brng);
4498 BHi : constant Node_Id := High_Bound (Brng);
4499 Small : constant Ureal := Small_Value (Typ);
4506 function Fsize (Lov, Hiv : Ureal) return Nat;
4507 -- Returns size of type with given bounds. Also leaves these
4508 -- bounds set as the current bounds of the Typ.
4514 function Fsize (Lov, Hiv : Ureal) return Nat is
4516 Set_Realval (Lo, Lov);
4517 Set_Realval (Hi, Hiv);
4518 return Minimum_Size (Typ);
4521 -- Start of processing for Freeze_Fixed_Point_Type
4524 -- If Esize of a subtype has not previously been set, set it now
4526 if Unknown_Esize (Typ) then
4527 Atype := Ancestor_Subtype (Typ);
4529 if Present (Atype) then
4530 Set_Esize (Typ, Esize (Atype));
4532 Set_Esize (Typ, Esize (Base_Type (Typ)));
4536 -- Immediate return if the range is already analyzed. This means that
4537 -- the range is already set, and does not need to be computed by this
4540 if Analyzed (Rng) then
4544 -- Immediate return if either of the bounds raises Constraint_Error
4546 if Raises_Constraint_Error (Lo)
4547 or else Raises_Constraint_Error (Hi)
4552 Loval := Realval (Lo);
4553 Hival := Realval (Hi);
4555 -- Ordinary fixed-point case
4557 if Is_Ordinary_Fixed_Point_Type (Typ) then
4559 -- For the ordinary fixed-point case, we are allowed to fudge the
4560 -- end-points up or down by small. Generally we prefer to fudge up,
4561 -- i.e. widen the bounds for non-model numbers so that the end points
4562 -- are included. However there are cases in which this cannot be
4563 -- done, and indeed cases in which we may need to narrow the bounds.
4564 -- The following circuit makes the decision.
4566 -- Note: our terminology here is that Incl_EP means that the bounds
4567 -- are widened by Small if necessary to include the end points, and
4568 -- Excl_EP means that the bounds are narrowed by Small to exclude the
4569 -- end-points if this reduces the size.
4571 -- Note that in the Incl case, all we care about is including the
4572 -- end-points. In the Excl case, we want to narrow the bounds as
4573 -- much as permitted by the RM, to give the smallest possible size.
4576 Loval_Incl_EP : Ureal;
4577 Hival_Incl_EP : Ureal;
4579 Loval_Excl_EP : Ureal;
4580 Hival_Excl_EP : Ureal;
4586 First_Subt : Entity_Id;
4591 -- First step. Base types are required to be symmetrical. Right
4592 -- now, the base type range is a copy of the first subtype range.
4593 -- This will be corrected before we are done, but right away we
4594 -- need to deal with the case where both bounds are non-negative.
4595 -- In this case, we set the low bound to the negative of the high
4596 -- bound, to make sure that the size is computed to include the
4597 -- required sign. Note that we do not need to worry about the
4598 -- case of both bounds negative, because the sign will be dealt
4599 -- with anyway. Furthermore we can't just go making such a bound
4600 -- symmetrical, since in a twos-complement system, there is an
4601 -- extra negative value which could not be accommodated on the
4605 and then not UR_Is_Negative (Loval)
4606 and then Hival > Loval
4609 Set_Realval (Lo, Loval);
4612 -- Compute the fudged bounds. If the number is a model number,
4613 -- then we do nothing to include it, but we are allowed to backoff
4614 -- to the next adjacent model number when we exclude it. If it is
4615 -- not a model number then we straddle the two values with the
4616 -- model numbers on either side.
4618 Model_Num := UR_Trunc (Loval / Small) * Small;
4620 if Loval = Model_Num then
4621 Loval_Incl_EP := Model_Num;
4623 Loval_Incl_EP := Model_Num - Small;
4626 -- The low value excluding the end point is Small greater, but
4627 -- we do not do this exclusion if the low value is positive,
4628 -- since it can't help the size and could actually hurt by
4629 -- crossing the high bound.
4631 if UR_Is_Negative (Loval_Incl_EP) then
4632 Loval_Excl_EP := Loval_Incl_EP + Small;
4634 -- If the value went from negative to zero, then we have the
4635 -- case where Loval_Incl_EP is the model number just below
4636 -- zero, so we want to stick to the negative value for the
4637 -- base type to maintain the condition that the size will
4638 -- include signed values.
4641 and then UR_Is_Zero (Loval_Excl_EP)
4643 Loval_Excl_EP := Loval_Incl_EP;
4647 Loval_Excl_EP := Loval_Incl_EP;
4650 -- Similar processing for upper bound and high value
4652 Model_Num := UR_Trunc (Hival / Small) * Small;
4654 if Hival = Model_Num then
4655 Hival_Incl_EP := Model_Num;
4657 Hival_Incl_EP := Model_Num + Small;
4660 if UR_Is_Positive (Hival_Incl_EP) then
4661 Hival_Excl_EP := Hival_Incl_EP - Small;
4663 Hival_Excl_EP := Hival_Incl_EP;
4666 -- One further adjustment is needed. In the case of subtypes, we
4667 -- cannot go outside the range of the base type, or we get
4668 -- peculiarities, and the base type range is already set. This
4669 -- only applies to the Incl values, since clearly the Excl values
4670 -- are already as restricted as they are allowed to be.
4673 Loval_Incl_EP := UR_Max (Loval_Incl_EP, Realval (BLo));
4674 Hival_Incl_EP := UR_Min (Hival_Incl_EP, Realval (BHi));
4677 -- Get size including and excluding end points
4679 Size_Incl_EP := Fsize (Loval_Incl_EP, Hival_Incl_EP);
4680 Size_Excl_EP := Fsize (Loval_Excl_EP, Hival_Excl_EP);
4682 -- No need to exclude end-points if it does not reduce size
4684 if Fsize (Loval_Incl_EP, Hival_Excl_EP) = Size_Excl_EP then
4685 Loval_Excl_EP := Loval_Incl_EP;
4688 if Fsize (Loval_Excl_EP, Hival_Incl_EP) = Size_Excl_EP then
4689 Hival_Excl_EP := Hival_Incl_EP;
4692 -- Now we set the actual size to be used. We want to use the
4693 -- bounds fudged up to include the end-points but only if this
4694 -- can be done without violating a specifically given size
4695 -- size clause or causing an unacceptable increase in size.
4697 -- Case of size clause given
4699 if Has_Size_Clause (Typ) then
4701 -- Use the inclusive size only if it is consistent with
4702 -- the explicitly specified size.
4704 if Size_Incl_EP <= RM_Size (Typ) then
4705 Actual_Lo := Loval_Incl_EP;
4706 Actual_Hi := Hival_Incl_EP;
4707 Actual_Size := Size_Incl_EP;
4709 -- If the inclusive size is too large, we try excluding
4710 -- the end-points (will be caught later if does not work).
4713 Actual_Lo := Loval_Excl_EP;
4714 Actual_Hi := Hival_Excl_EP;
4715 Actual_Size := Size_Excl_EP;
4718 -- Case of size clause not given
4721 -- If we have a base type whose corresponding first subtype
4722 -- has an explicit size that is large enough to include our
4723 -- end-points, then do so. There is no point in working hard
4724 -- to get a base type whose size is smaller than the specified
4725 -- size of the first subtype.
4727 First_Subt := First_Subtype (Typ);
4729 if Has_Size_Clause (First_Subt)
4730 and then Size_Incl_EP <= Esize (First_Subt)
4732 Actual_Size := Size_Incl_EP;
4733 Actual_Lo := Loval_Incl_EP;
4734 Actual_Hi := Hival_Incl_EP;
4736 -- If excluding the end-points makes the size smaller and
4737 -- results in a size of 8,16,32,64, then we take the smaller
4738 -- size. For the 64 case, this is compulsory. For the other
4739 -- cases, it seems reasonable. We like to include end points
4740 -- if we can, but not at the expense of moving to the next
4741 -- natural boundary of size.
4743 elsif Size_Incl_EP /= Size_Excl_EP
4745 (Size_Excl_EP = 8 or else
4746 Size_Excl_EP = 16 or else
4747 Size_Excl_EP = 32 or else
4750 Actual_Size := Size_Excl_EP;
4751 Actual_Lo := Loval_Excl_EP;
4752 Actual_Hi := Hival_Excl_EP;
4754 -- Otherwise we can definitely include the end points
4757 Actual_Size := Size_Incl_EP;
4758 Actual_Lo := Loval_Incl_EP;
4759 Actual_Hi := Hival_Incl_EP;
4762 -- One pathological case: normally we never fudge a low bound
4763 -- down, since it would seem to increase the size (if it has
4764 -- any effect), but for ranges containing single value, or no
4765 -- values, the high bound can be small too large. Consider:
4767 -- type t is delta 2.0**(-14)
4768 -- range 131072.0 .. 0;
4770 -- That lower bound is *just* outside the range of 32 bits, and
4771 -- does need fudging down in this case. Note that the bounds
4772 -- will always have crossed here, since the high bound will be
4773 -- fudged down if necessary, as in the case of:
4775 -- type t is delta 2.0**(-14)
4776 -- range 131072.0 .. 131072.0;
4778 -- So we detect the situation by looking for crossed bounds,
4779 -- and if the bounds are crossed, and the low bound is greater
4780 -- than zero, we will always back it off by small, since this
4781 -- is completely harmless.
4783 if Actual_Lo > Actual_Hi then
4784 if UR_Is_Positive (Actual_Lo) then
4785 Actual_Lo := Loval_Incl_EP - Small;
4786 Actual_Size := Fsize (Actual_Lo, Actual_Hi);
4788 -- And of course, we need to do exactly the same parallel
4789 -- fudge for flat ranges in the negative region.
4791 elsif UR_Is_Negative (Actual_Hi) then
4792 Actual_Hi := Hival_Incl_EP + Small;
4793 Actual_Size := Fsize (Actual_Lo, Actual_Hi);
4798 Set_Realval (Lo, Actual_Lo);
4799 Set_Realval (Hi, Actual_Hi);
4802 -- For the decimal case, none of this fudging is required, since there
4803 -- are no end-point problems in the decimal case (the end-points are
4804 -- always included).
4807 Actual_Size := Fsize (Loval, Hival);
4810 -- At this stage, the actual size has been calculated and the proper
4811 -- required bounds are stored in the low and high bounds.
4813 if Actual_Size > 64 then
4814 Error_Msg_Uint_1 := UI_From_Int (Actual_Size);
4816 ("size required (^) for type& too large, maximum allowed is 64",
4821 -- Check size against explicit given size
4823 if Has_Size_Clause (Typ) then
4824 if Actual_Size > RM_Size (Typ) then
4825 Error_Msg_Uint_1 := RM_Size (Typ);
4826 Error_Msg_Uint_2 := UI_From_Int (Actual_Size);
4828 ("size given (^) for type& too small, minimum allowed is ^",
4829 Size_Clause (Typ), Typ);
4832 Actual_Size := UI_To_Int (Esize (Typ));
4835 -- Increase size to next natural boundary if no size clause given
4838 if Actual_Size <= 8 then
4840 elsif Actual_Size <= 16 then
4842 elsif Actual_Size <= 32 then
4848 Init_Esize (Typ, Actual_Size);
4849 Adjust_Esize_For_Alignment (Typ);
4852 -- If we have a base type, then expand the bounds so that they extend to
4853 -- the full width of the allocated size in bits, to avoid junk range
4854 -- checks on intermediate computations.
4856 if Base_Type (Typ) = Typ then
4857 Set_Realval (Lo, -(Small * (Uint_2 ** (Actual_Size - 1))));
4858 Set_Realval (Hi, (Small * (Uint_2 ** (Actual_Size - 1) - 1)));
4861 -- Final step is to reanalyze the bounds using the proper type
4862 -- and set the Corresponding_Integer_Value fields of the literals.
4864 Set_Etype (Lo, Empty);
4865 Set_Analyzed (Lo, False);
4868 -- Resolve with universal fixed if the base type, and the base type if
4869 -- it is a subtype. Note we can't resolve the base type with itself,
4870 -- that would be a reference before definition.
4873 Resolve (Lo, Universal_Fixed);
4878 -- Set corresponding integer value for bound
4880 Set_Corresponding_Integer_Value
4881 (Lo, UR_To_Uint (Realval (Lo) / Small));
4883 -- Similar processing for high bound
4885 Set_Etype (Hi, Empty);
4886 Set_Analyzed (Hi, False);
4890 Resolve (Hi, Universal_Fixed);
4895 Set_Corresponding_Integer_Value
4896 (Hi, UR_To_Uint (Realval (Hi) / Small));
4898 -- Set type of range to correspond to bounds
4900 Set_Etype (Rng, Etype (Lo));
4902 -- Set Esize to calculated size if not set already
4904 if Unknown_Esize (Typ) then
4905 Init_Esize (Typ, Actual_Size);
4908 -- Set RM_Size if not already set. If already set, check value
4911 Minsiz : constant Uint := UI_From_Int (Minimum_Size (Typ));
4914 if RM_Size (Typ) /= Uint_0 then
4915 if RM_Size (Typ) < Minsiz then
4916 Error_Msg_Uint_1 := RM_Size (Typ);
4917 Error_Msg_Uint_2 := Minsiz;
4919 ("size given (^) for type& too small, minimum allowed is ^",
4920 Size_Clause (Typ), Typ);
4924 Set_RM_Size (Typ, Minsiz);
4927 end Freeze_Fixed_Point_Type;
4933 procedure Freeze_Itype (T : Entity_Id; N : Node_Id) is
4937 Set_Has_Delayed_Freeze (T);
4938 L := Freeze_Entity (T, Sloc (N));
4940 if Is_Non_Empty_List (L) then
4941 Insert_Actions (N, L);
4945 --------------------------
4946 -- Freeze_Static_Object --
4947 --------------------------
4949 procedure Freeze_Static_Object (E : Entity_Id) is
4951 Cannot_Be_Static : exception;
4952 -- Exception raised if the type of a static object cannot be made
4953 -- static. This happens if the type depends on non-global objects.
4955 procedure Ensure_Expression_Is_SA (N : Node_Id);
4956 -- Called to ensure that an expression used as part of a type definition
4957 -- is statically allocatable, which means that the expression type is
4958 -- statically allocatable, and the expression is either static, or a
4959 -- reference to a library level constant.
4961 procedure Ensure_Type_Is_SA (Typ : Entity_Id);
4962 -- Called to mark a type as static, checking that it is possible
4963 -- to set the type as static. If it is not possible, then the
4964 -- exception Cannot_Be_Static is raised.
4966 -----------------------------
4967 -- Ensure_Expression_Is_SA --
4968 -----------------------------
4970 procedure Ensure_Expression_Is_SA (N : Node_Id) is
4974 Ensure_Type_Is_SA (Etype (N));
4976 if Is_Static_Expression (N) then
4979 elsif Nkind (N) = N_Identifier then
4983 and then Ekind (Ent) = E_Constant
4984 and then Is_Library_Level_Entity (Ent)
4990 raise Cannot_Be_Static;
4991 end Ensure_Expression_Is_SA;
4993 -----------------------
4994 -- Ensure_Type_Is_SA --
4995 -----------------------
4997 procedure Ensure_Type_Is_SA (Typ : Entity_Id) is
5002 -- If type is library level, we are all set
5004 if Is_Library_Level_Entity (Typ) then
5008 -- We are also OK if the type already marked as statically allocated,
5009 -- which means we processed it before.
5011 if Is_Statically_Allocated (Typ) then
5015 -- Mark type as statically allocated
5017 Set_Is_Statically_Allocated (Typ);
5019 -- Check that it is safe to statically allocate this type
5021 if Is_Scalar_Type (Typ) or else Is_Real_Type (Typ) then
5022 Ensure_Expression_Is_SA (Type_Low_Bound (Typ));
5023 Ensure_Expression_Is_SA (Type_High_Bound (Typ));
5025 elsif Is_Array_Type (Typ) then
5026 N := First_Index (Typ);
5027 while Present (N) loop
5028 Ensure_Type_Is_SA (Etype (N));
5032 Ensure_Type_Is_SA (Component_Type (Typ));
5034 elsif Is_Access_Type (Typ) then
5035 if Ekind (Designated_Type (Typ)) = E_Subprogram_Type then
5039 T : constant Entity_Id := Etype (Designated_Type (Typ));
5042 if T /= Standard_Void_Type then
5043 Ensure_Type_Is_SA (T);
5046 F := First_Formal (Designated_Type (Typ));
5048 while Present (F) loop
5049 Ensure_Type_Is_SA (Etype (F));
5055 Ensure_Type_Is_SA (Designated_Type (Typ));
5058 elsif Is_Record_Type (Typ) then
5059 C := First_Entity (Typ);
5060 while Present (C) loop
5061 if Ekind (C) = E_Discriminant
5062 or else Ekind (C) = E_Component
5064 Ensure_Type_Is_SA (Etype (C));
5066 elsif Is_Type (C) then
5067 Ensure_Type_Is_SA (C);
5073 elsif Ekind (Typ) = E_Subprogram_Type then
5074 Ensure_Type_Is_SA (Etype (Typ));
5076 C := First_Formal (Typ);
5077 while Present (C) loop
5078 Ensure_Type_Is_SA (Etype (C));
5083 raise Cannot_Be_Static;
5085 end Ensure_Type_Is_SA;
5087 -- Start of processing for Freeze_Static_Object
5090 Ensure_Type_Is_SA (Etype (E));
5093 when Cannot_Be_Static =>
5095 -- If the object that cannot be static is imported or exported,
5096 -- then we give an error message saying that this object cannot
5097 -- be imported or exported. If it has an address clause it is
5098 -- an overlay in the current partition and the static requirement
5102 and then No (Address_Clause (E))
5105 ("& cannot be imported (local type is not constant)", E);
5107 -- Otherwise must be exported, something is wrong if compiler
5108 -- is marking something as statically allocated which cannot be).
5110 else pragma Assert (Is_Exported (E));
5112 ("& cannot be exported (local type is not constant)", E);
5114 end Freeze_Static_Object;
5116 -----------------------
5117 -- Freeze_Subprogram --
5118 -----------------------
5120 procedure Freeze_Subprogram (E : Entity_Id) is
5125 -- Subprogram may not have an address clause unless it is imported
5127 if Present (Address_Clause (E)) then
5128 if not Is_Imported (E) then
5130 ("address clause can only be given " &
5131 "for imported subprogram",
5132 Name (Address_Clause (E)));
5136 -- Reset the Pure indication on an imported subprogram unless an
5137 -- explicit Pure_Function pragma was present. We do this because
5138 -- otherwise it is an insidious error to call a non-pure function from
5139 -- pure unit and have calls mysteriously optimized away. What happens
5140 -- here is that the Import can bypass the normal check to ensure that
5141 -- pure units call only pure subprograms.
5144 and then Is_Pure (E)
5145 and then not Has_Pragma_Pure_Function (E)
5147 Set_Is_Pure (E, False);
5150 -- For non-foreign convention subprograms, this is where we create
5151 -- the extra formals (for accessibility level and constrained bit
5152 -- information). We delay this till the freeze point precisely so
5153 -- that we know the convention!
5155 if not Has_Foreign_Convention (E) then
5156 Create_Extra_Formals (E);
5159 -- If this is convention Ada and a Valued_Procedure, that's odd
5161 if Ekind (E) = E_Procedure
5162 and then Is_Valued_Procedure (E)
5163 and then Convention (E) = Convention_Ada
5164 and then Warn_On_Export_Import
5167 ("?Valued_Procedure has no effect for convention Ada", E);
5168 Set_Is_Valued_Procedure (E, False);
5171 -- Case of foreign convention
5176 -- For foreign conventions, warn about return of an
5177 -- unconstrained array.
5179 -- Note: we *do* allow a return by descriptor for the VMS case,
5180 -- though here there is probably more to be done ???
5182 if Ekind (E) = E_Function then
5183 Retype := Underlying_Type (Etype (E));
5185 -- If no return type, probably some other error, e.g. a
5186 -- missing full declaration, so ignore.
5191 -- If the return type is generic, we have emitted a warning
5192 -- earlier on, and there is nothing else to check here. Specific
5193 -- instantiations may lead to erroneous behavior.
5195 elsif Is_Generic_Type (Etype (E)) then
5198 -- Display warning if returning unconstrained array
5200 elsif Is_Array_Type (Retype)
5201 and then not Is_Constrained (Retype)
5203 -- Exclude cases where descriptor mechanism is set, since the
5204 -- VMS descriptor mechanisms allow such unconstrained returns.
5206 and then Mechanism (E) not in Descriptor_Codes
5208 -- Check appropriate warning is enabled (should we check for
5209 -- Warnings (Off) on specific entities here, probably so???)
5211 and then Warn_On_Export_Import
5213 -- Exclude the VM case, since return of unconstrained arrays
5214 -- is properly handled in both the JVM and .NET cases.
5216 and then VM_Target = No_VM
5219 ("?foreign convention function& should not return " &
5220 "unconstrained array", E);
5225 -- If any of the formals for an exported foreign convention
5226 -- subprogram have defaults, then emit an appropriate warning since
5227 -- this is odd (default cannot be used from non-Ada code)
5229 if Is_Exported (E) then
5230 F := First_Formal (E);
5231 while Present (F) loop
5232 if Warn_On_Export_Import
5233 and then Present (Default_Value (F))
5236 ("?parameter cannot be defaulted in non-Ada call",
5245 -- For VMS, descriptor mechanisms for parameters are allowed only for
5246 -- imported/exported subprograms. Moreover, the NCA descriptor is not
5247 -- allowed for parameters of exported subprograms.
5249 if OpenVMS_On_Target then
5250 if Is_Exported (E) then
5251 F := First_Formal (E);
5252 while Present (F) loop
5253 if Mechanism (F) = By_Descriptor_NCA then
5255 ("'N'C'A' descriptor for parameter not permitted", F);
5257 ("\can only be used for imported subprogram", F);
5263 elsif not Is_Imported (E) then
5264 F := First_Formal (E);
5265 while Present (F) loop
5266 if Mechanism (F) in Descriptor_Codes then
5268 ("descriptor mechanism for parameter not permitted", F);
5270 ("\can only be used for imported/exported subprogram", F);
5278 -- Pragma Inline_Always is disallowed for dispatching subprograms
5279 -- because the address of such subprograms is saved in the dispatch
5280 -- table to support dispatching calls, and dispatching calls cannot
5281 -- be inlined. This is consistent with the restriction against using
5282 -- 'Access or 'Address on an Inline_Always subprogram.
5284 if Is_Dispatching_Operation (E)
5285 and then Has_Pragma_Inline_Always (E)
5288 ("pragma Inline_Always not allowed for dispatching subprograms", E);
5291 -- Because of the implicit representation of inherited predefined
5292 -- operators in the front-end, the overriding status of the operation
5293 -- may be affected when a full view of a type is analyzed, and this is
5294 -- not captured by the analysis of the corresponding type declaration.
5295 -- Therefore the correctness of a not-overriding indicator must be
5296 -- rechecked when the subprogram is frozen.
5298 if Nkind (E) = N_Defining_Operator_Symbol
5299 and then not Error_Posted (Parent (E))
5301 Check_Overriding_Indicator (E, Empty, Is_Primitive (E));
5303 end Freeze_Subprogram;
5305 ----------------------
5306 -- Is_Fully_Defined --
5307 ----------------------
5309 function Is_Fully_Defined (T : Entity_Id) return Boolean is
5311 if Ekind (T) = E_Class_Wide_Type then
5312 return Is_Fully_Defined (Etype (T));
5314 elsif Is_Array_Type (T) then
5315 return Is_Fully_Defined (Component_Type (T));
5317 elsif Is_Record_Type (T)
5318 and not Is_Private_Type (T)
5320 -- Verify that the record type has no components with private types
5321 -- without completion.
5327 Comp := First_Component (T);
5329 while Present (Comp) loop
5330 if not Is_Fully_Defined (Etype (Comp)) then
5334 Next_Component (Comp);
5340 return not Is_Private_Type (T)
5341 or else Present (Full_View (Base_Type (T)));
5343 end Is_Fully_Defined;
5345 ---------------------------------
5346 -- Process_Default_Expressions --
5347 ---------------------------------
5349 procedure Process_Default_Expressions
5351 After : in out Node_Id)
5353 Loc : constant Source_Ptr := Sloc (E);
5360 Set_Default_Expressions_Processed (E);
5362 -- A subprogram instance and its associated anonymous subprogram share
5363 -- their signature. The default expression functions are defined in the
5364 -- wrapper packages for the anonymous subprogram, and should not be
5365 -- generated again for the instance.
5367 if Is_Generic_Instance (E)
5368 and then Present (Alias (E))
5369 and then Default_Expressions_Processed (Alias (E))
5374 Formal := First_Formal (E);
5375 while Present (Formal) loop
5376 if Present (Default_Value (Formal)) then
5378 -- We work with a copy of the default expression because we
5379 -- do not want to disturb the original, since this would mess
5380 -- up the conformance checking.
5382 Dcopy := New_Copy_Tree (Default_Value (Formal));
5384 -- The analysis of the expression may generate insert actions,
5385 -- which of course must not be executed. We wrap those actions
5386 -- in a procedure that is not called, and later on eliminated.
5387 -- The following cases have no side-effects, and are analyzed
5390 if Nkind (Dcopy) = N_Identifier
5391 or else Nkind (Dcopy) = N_Expanded_Name
5392 or else Nkind (Dcopy) = N_Integer_Literal
5393 or else (Nkind (Dcopy) = N_Real_Literal
5394 and then not Vax_Float (Etype (Dcopy)))
5395 or else Nkind (Dcopy) = N_Character_Literal
5396 or else Nkind (Dcopy) = N_String_Literal
5397 or else Known_Null (Dcopy)
5398 or else (Nkind (Dcopy) = N_Attribute_Reference
5400 Attribute_Name (Dcopy) = Name_Null_Parameter)
5403 -- If there is no default function, we must still do a full
5404 -- analyze call on the default value, to ensure that all error
5405 -- checks are performed, e.g. those associated with static
5406 -- evaluation. Note: this branch will always be taken if the
5407 -- analyzer is turned off (but we still need the error checks).
5409 -- Note: the setting of parent here is to meet the requirement
5410 -- that we can only analyze the expression while attached to
5411 -- the tree. Really the requirement is that the parent chain
5412 -- be set, we don't actually need to be in the tree.
5414 Set_Parent (Dcopy, Declaration_Node (Formal));
5417 -- Default expressions are resolved with their own type if the
5418 -- context is generic, to avoid anomalies with private types.
5420 if Ekind (Scope (E)) = E_Generic_Package then
5423 Resolve (Dcopy, Etype (Formal));
5426 -- If that resolved expression will raise constraint error,
5427 -- then flag the default value as raising constraint error.
5428 -- This allows a proper error message on the calls.
5430 if Raises_Constraint_Error (Dcopy) then
5431 Set_Raises_Constraint_Error (Default_Value (Formal));
5434 -- If the default is a parameterless call, we use the name of
5435 -- the called function directly, and there is no body to build.
5437 elsif Nkind (Dcopy) = N_Function_Call
5438 and then No (Parameter_Associations (Dcopy))
5442 -- Else construct and analyze the body of a wrapper procedure
5443 -- that contains an object declaration to hold the expression.
5444 -- Given that this is done only to complete the analysis, it
5445 -- simpler to build a procedure than a function which might
5446 -- involve secondary stack expansion.
5450 Make_Defining_Identifier (Loc, New_Internal_Name ('D'));
5453 Make_Subprogram_Body (Loc,
5455 Make_Procedure_Specification (Loc,
5456 Defining_Unit_Name => Dnam),
5458 Declarations => New_List (
5459 Make_Object_Declaration (Loc,
5460 Defining_Identifier =>
5461 Make_Defining_Identifier (Loc,
5462 New_Internal_Name ('T')),
5463 Object_Definition =>
5464 New_Occurrence_Of (Etype (Formal), Loc),
5465 Expression => New_Copy_Tree (Dcopy))),
5467 Handled_Statement_Sequence =>
5468 Make_Handled_Sequence_Of_Statements (Loc,
5469 Statements => New_List));
5471 Set_Scope (Dnam, Scope (E));
5472 Set_Assignment_OK (First (Declarations (Dbody)));
5473 Set_Is_Eliminated (Dnam);
5474 Insert_After (After, Dbody);
5480 Next_Formal (Formal);
5482 end Process_Default_Expressions;
5484 ----------------------------------------
5485 -- Set_Component_Alignment_If_Not_Set --
5486 ----------------------------------------
5488 procedure Set_Component_Alignment_If_Not_Set (Typ : Entity_Id) is
5490 -- Ignore if not base type, subtypes don't need anything
5492 if Typ /= Base_Type (Typ) then
5496 -- Do not override existing representation
5498 if Is_Packed (Typ) then
5501 elsif Has_Specified_Layout (Typ) then
5504 elsif Component_Alignment (Typ) /= Calign_Default then
5508 Set_Component_Alignment
5509 (Typ, Scope_Stack.Table
5510 (Scope_Stack.Last).Component_Alignment_Default);
5512 end Set_Component_Alignment_If_Not_Set;
5518 procedure Undelay_Type (T : Entity_Id) is
5520 Set_Has_Delayed_Freeze (T, False);
5521 Set_Freeze_Node (T, Empty);
5523 -- Since we don't want T to have a Freeze_Node, we don't want its
5524 -- Full_View or Corresponding_Record_Type to have one either.
5526 -- ??? Fundamentally, this whole handling is a kludge. What we really
5527 -- want is to be sure that for an Itype that's part of record R and is a
5528 -- subtype of type T, that it's frozen after the later of the freeze
5529 -- points of R and T. We have no way of doing that directly, so what we
5530 -- do is force most such Itypes to be frozen as part of freezing R via
5531 -- this procedure and only delay the ones that need to be delayed
5532 -- (mostly the designated types of access types that are defined as part
5535 if Is_Private_Type (T)
5536 and then Present (Full_View (T))
5537 and then Is_Itype (Full_View (T))
5538 and then Is_Record_Type (Scope (Full_View (T)))
5540 Undelay_Type (Full_View (T));
5543 if Is_Concurrent_Type (T)
5544 and then Present (Corresponding_Record_Type (T))
5545 and then Is_Itype (Corresponding_Record_Type (T))
5546 and then Is_Record_Type (Scope (Corresponding_Record_Type (T)))
5548 Undelay_Type (Corresponding_Record_Type (T));
5556 procedure Warn_Overlay
5561 Ent : constant Entity_Id := Entity (Nam);
5562 -- The object to which the address clause applies
5565 Old : Entity_Id := Empty;
5569 -- No warning if address clause overlay warnings are off
5571 if not Address_Clause_Overlay_Warnings then
5575 -- No warning if there is an explicit initialization
5577 Init := Original_Node (Expression (Declaration_Node (Ent)));
5579 if Present (Init) and then Comes_From_Source (Init) then
5583 -- We only give the warning for non-imported entities of a type for
5584 -- which a non-null base init proc is defined, or for objects of access
5585 -- types with implicit null initialization, or when Initialize_Scalars
5586 -- applies and the type is scalar or a string type (the latter being
5587 -- tested for because predefined String types are initialized by inline
5588 -- code rather than by an init_proc).
5591 and then not Is_Imported (Ent)
5592 and then (Has_Non_Null_Base_Init_Proc (Typ)
5593 or else Is_Access_Type (Typ)
5594 or else (Init_Or_Norm_Scalars
5595 and then (Is_Scalar_Type (Typ)
5596 or else Is_String_Type (Typ))))
5598 if Nkind (Expr) = N_Attribute_Reference
5599 and then Is_Entity_Name (Prefix (Expr))
5601 Old := Entity (Prefix (Expr));
5603 elsif Is_Entity_Name (Expr)
5604 and then Ekind (Entity (Expr)) = E_Constant
5606 Decl := Declaration_Node (Entity (Expr));
5608 if Nkind (Decl) = N_Object_Declaration
5609 and then Present (Expression (Decl))
5610 and then Nkind (Expression (Decl)) = N_Attribute_Reference
5611 and then Is_Entity_Name (Prefix (Expression (Decl)))
5613 Old := Entity (Prefix (Expression (Decl)));
5615 elsif Nkind (Expr) = N_Function_Call then
5619 -- A function call (most likely to To_Address) is probably not an
5620 -- overlay, so skip warning. Ditto if the function call was inlined
5621 -- and transformed into an entity.
5623 elsif Nkind (Original_Node (Expr)) = N_Function_Call then
5627 Decl := Next (Parent (Expr));
5629 -- If a pragma Import follows, we assume that it is for the current
5630 -- target of the address clause, and skip the warning.
5633 and then Nkind (Decl) = N_Pragma
5634 and then Pragma_Name (Decl) = Name_Import
5639 if Present (Old) then
5640 Error_Msg_Node_2 := Old;
5642 ("default initialization of & may modify &?",
5646 ("default initialization of & may modify overlaid storage?",
5650 -- Add friendly warning if initialization comes from a packed array
5653 if Is_Record_Type (Typ) then
5658 Comp := First_Component (Typ);
5660 while Present (Comp) loop
5661 if Nkind (Parent (Comp)) = N_Component_Declaration
5662 and then Present (Expression (Parent (Comp)))
5665 elsif Is_Array_Type (Etype (Comp))
5666 and then Present (Packed_Array_Type (Etype (Comp)))
5669 ("\packed array component& " &
5670 "will be initialized to zero?",
5674 Next_Component (Comp);
5681 ("\use pragma Import for & to " &
5682 "suppress initialization (RM B.1(24))?",