1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2010, 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;
40 with Namet; use Namet;
41 with Nlists; use Nlists;
42 with Nmake; use Nmake;
44 with Restrict; use Restrict;
45 with Rident; use Rident;
47 with Sem_Aux; use Sem_Aux;
48 with Sem_Cat; use Sem_Cat;
49 with Sem_Ch6; use Sem_Ch6;
50 with Sem_Ch7; use Sem_Ch7;
51 with Sem_Ch8; use Sem_Ch8;
52 with Sem_Ch13; use Sem_Ch13;
53 with Sem_Eval; use Sem_Eval;
54 with Sem_Mech; use Sem_Mech;
55 with Sem_Prag; use Sem_Prag;
56 with Sem_Res; use Sem_Res;
57 with Sem_Util; use Sem_Util;
58 with Sinfo; use Sinfo;
59 with Snames; use Snames;
60 with Stand; use Stand;
61 with Targparm; use Targparm;
62 with Tbuild; use Tbuild;
63 with Ttypes; use Ttypes;
64 with Uintp; use Uintp;
65 with Urealp; use Urealp;
67 package body Freeze is
69 -----------------------
70 -- Local Subprograms --
71 -----------------------
73 procedure Adjust_Esize_For_Alignment (Typ : Entity_Id);
74 -- Typ is a type that is being frozen. If no size clause is given,
75 -- but a default Esize has been computed, then this default Esize is
76 -- adjusted up if necessary to be consistent with a given alignment,
77 -- but never to a value greater than Long_Long_Integer'Size. This
78 -- is used for all discrete types and for fixed-point types.
80 procedure Build_And_Analyze_Renamed_Body
83 After : in out Node_Id);
84 -- Build body for a renaming declaration, insert in tree and analyze
86 procedure Check_Address_Clause (E : Entity_Id);
87 -- Apply legality checks to address clauses for object declarations,
88 -- at the point the object is frozen.
90 procedure Check_Strict_Alignment (E : Entity_Id);
91 -- E is a base type. If E is tagged or has a component that is aliased
92 -- or tagged or contains something this is aliased or tagged, set
95 procedure Check_Unsigned_Type (E : Entity_Id);
96 pragma Inline (Check_Unsigned_Type);
97 -- If E is a fixed-point or discrete type, then all the necessary work
98 -- to freeze it is completed except for possible setting of the flag
99 -- Is_Unsigned_Type, which is done by this procedure. The call has no
100 -- effect if the entity E is not a discrete or fixed-point type.
102 procedure Freeze_And_Append
105 Result : in out List_Id);
106 -- Freezes Ent using Freeze_Entity, and appends the resulting list of
107 -- nodes to Result, modifying Result from No_List if necessary.
109 procedure Freeze_Enumeration_Type (Typ : Entity_Id);
110 -- Freeze enumeration type. The Esize field is set as processing
111 -- proceeds (i.e. set by default when the type is declared and then
112 -- adjusted by rep clauses. What this procedure does is to make sure
113 -- that if a foreign convention is specified, and no specific size
114 -- is given, then the size must be at least Integer'Size.
116 procedure Freeze_Static_Object (E : Entity_Id);
117 -- If an object is frozen which has Is_Statically_Allocated set, then
118 -- all referenced types must also be marked with this flag. This routine
119 -- is in charge of meeting this requirement for the object entity E.
121 procedure Freeze_Subprogram (E : Entity_Id);
122 -- Perform freezing actions for a subprogram (create extra formals,
123 -- and set proper default mechanism values). Note that this routine
124 -- is not called for internal subprograms, for which neither of these
125 -- actions is needed (or desirable, we do not want for example to have
126 -- these extra formals present in initialization procedures, where they
127 -- would serve no purpose). In this call E is either a subprogram or
128 -- a subprogram type (i.e. an access to a subprogram).
130 function Is_Fully_Defined (T : Entity_Id) return Boolean;
131 -- True if T is not private and has no private components, or has a full
132 -- view. Used to determine whether the designated type of an access type
133 -- should be frozen when the access type is frozen. This is done when an
134 -- allocator is frozen, or an expression that may involve attributes of
135 -- the designated type. Otherwise freezing the access type does not freeze
136 -- the designated type.
138 procedure Process_Default_Expressions
140 After : in out Node_Id);
141 -- This procedure is called for each subprogram to complete processing
142 -- of default expressions at the point where all types are known to be
143 -- frozen. The expressions must be analyzed in full, to make sure that
144 -- all error processing is done (they have only been pre-analyzed). If
145 -- the expression is not an entity or literal, its analysis may generate
146 -- code which must not be executed. In that case we build a function
147 -- body to hold that code. This wrapper function serves no other purpose
148 -- (it used to be called to evaluate the default, but now the default is
149 -- inlined at each point of call).
151 procedure Set_Component_Alignment_If_Not_Set (Typ : Entity_Id);
152 -- Typ is a record or array type that is being frozen. This routine
153 -- sets the default component alignment from the scope stack values
154 -- if the alignment is otherwise not specified.
156 procedure Check_Debug_Info_Needed (T : Entity_Id);
157 -- As each entity is frozen, this routine is called to deal with the
158 -- setting of Debug_Info_Needed for the entity. This flag is set if
159 -- the entity comes from source, or if we are in Debug_Generated_Code
160 -- mode or if the -gnatdV debug flag is set. However, it never sets
161 -- the flag if Debug_Info_Off is set. This procedure also ensures that
162 -- subsidiary entities have the flag set as required.
164 procedure Undelay_Type (T : Entity_Id);
165 -- T is a type of a component that we know to be an Itype.
166 -- We don't want this to have a Freeze_Node, so ensure it doesn't.
167 -- Do the same for any Full_View or Corresponding_Record_Type.
169 procedure Warn_Overlay
173 -- Expr is the expression for an address clause for entity Nam whose type
174 -- is Typ. If Typ has a default initialization, and there is no explicit
175 -- initialization in the source declaration, check whether the address
176 -- clause might cause overlaying of an entity, and emit a warning on the
177 -- side effect that the initialization will cause.
179 -------------------------------
180 -- Adjust_Esize_For_Alignment --
181 -------------------------------
183 procedure Adjust_Esize_For_Alignment (Typ : Entity_Id) is
187 if Known_Esize (Typ) and then Known_Alignment (Typ) then
188 Align := Alignment_In_Bits (Typ);
190 if Align > Esize (Typ)
191 and then Align <= Standard_Long_Long_Integer_Size
193 Set_Esize (Typ, Align);
196 end Adjust_Esize_For_Alignment;
198 ------------------------------------
199 -- Build_And_Analyze_Renamed_Body --
200 ------------------------------------
202 procedure Build_And_Analyze_Renamed_Body
205 After : in out Node_Id)
207 Body_Decl : constant Node_Id := Unit_Declaration_Node (New_S);
208 Ent : constant Entity_Id := Defining_Entity (Decl);
210 Renamed_Subp : Entity_Id;
213 -- If the renamed subprogram is intrinsic, there is no need for a
214 -- wrapper body: we set the alias that will be called and expanded which
215 -- completes the declaration. This transformation is only legal if the
216 -- renamed entity has already been elaborated.
218 -- Note that it is legal for a renaming_as_body to rename an intrinsic
219 -- subprogram, as long as the renaming occurs before the new entity
220 -- is frozen. See RM 8.5.4 (5).
222 if Nkind (Body_Decl) = N_Subprogram_Renaming_Declaration
223 and then Is_Entity_Name (Name (Body_Decl))
225 Renamed_Subp := Entity (Name (Body_Decl));
227 Renamed_Subp := Empty;
230 if Present (Renamed_Subp)
231 and then Is_Intrinsic_Subprogram (Renamed_Subp)
233 (not In_Same_Source_Unit (Renamed_Subp, Ent)
234 or else Sloc (Renamed_Subp) < Sloc (Ent))
236 -- We can make the renaming entity intrisic if the renamed function
237 -- has an interface name, or if it is one of the shift/rotate
238 -- operations known to the compiler.
240 and then (Present (Interface_Name (Renamed_Subp))
241 or else Chars (Renamed_Subp) = Name_Rotate_Left
242 or else Chars (Renamed_Subp) = Name_Rotate_Right
243 or else Chars (Renamed_Subp) = Name_Shift_Left
244 or else Chars (Renamed_Subp) = Name_Shift_Right
245 or else Chars (Renamed_Subp) = Name_Shift_Right_Arithmetic)
247 Set_Interface_Name (Ent, Interface_Name (Renamed_Subp));
249 if Present (Alias (Renamed_Subp)) then
250 Set_Alias (Ent, Alias (Renamed_Subp));
252 Set_Alias (Ent, Renamed_Subp);
255 Set_Is_Intrinsic_Subprogram (Ent);
256 Set_Has_Completion (Ent);
259 Body_Node := Build_Renamed_Body (Decl, New_S);
260 Insert_After (After, Body_Node);
261 Mark_Rewrite_Insertion (Body_Node);
265 end Build_And_Analyze_Renamed_Body;
267 ------------------------
268 -- Build_Renamed_Body --
269 ------------------------
271 function Build_Renamed_Body
273 New_S : Entity_Id) return Node_Id
275 Loc : constant Source_Ptr := Sloc (New_S);
276 -- We use for the source location of the renamed body, the location of
277 -- the spec entity. It might seem more natural to use the location of
278 -- the renaming declaration itself, but that would be wrong, since then
279 -- the body we create would look as though it was created far too late,
280 -- and this could cause problems with elaboration order analysis,
281 -- particularly in connection with instantiations.
283 N : constant Node_Id := Unit_Declaration_Node (New_S);
284 Nam : constant Node_Id := Name (N);
286 Spec : constant Node_Id := New_Copy_Tree (Specification (Decl));
287 Actuals : List_Id := No_List;
292 O_Formal : Entity_Id;
293 Param_Spec : Node_Id;
295 Pref : Node_Id := Empty;
296 -- If the renamed entity is a primitive operation given in prefix form,
297 -- the prefix is the target object and it has to be added as the first
298 -- actual in the generated call.
301 -- Determine the entity being renamed, which is the target of the call
302 -- statement. If the name is an explicit dereference, this is a renaming
303 -- of a subprogram type rather than a subprogram. The name itself is
306 if Nkind (Nam) = N_Selected_Component then
307 Old_S := Entity (Selector_Name (Nam));
309 elsif Nkind (Nam) = N_Explicit_Dereference then
310 Old_S := Etype (Nam);
312 elsif Nkind (Nam) = N_Indexed_Component then
313 if Is_Entity_Name (Prefix (Nam)) then
314 Old_S := Entity (Prefix (Nam));
316 Old_S := Entity (Selector_Name (Prefix (Nam)));
319 elsif Nkind (Nam) = N_Character_Literal then
320 Old_S := Etype (New_S);
323 Old_S := Entity (Nam);
326 if Is_Entity_Name (Nam) then
328 -- If the renamed entity is a predefined operator, retain full name
329 -- to ensure its visibility.
331 if Ekind (Old_S) = E_Operator
332 and then Nkind (Nam) = N_Expanded_Name
334 Call_Name := New_Copy (Name (N));
336 Call_Name := New_Reference_To (Old_S, Loc);
340 if Nkind (Nam) = N_Selected_Component
341 and then Present (First_Formal (Old_S))
343 (Is_Controlling_Formal (First_Formal (Old_S))
344 or else Is_Class_Wide_Type (Etype (First_Formal (Old_S))))
347 -- Retrieve the target object, to be added as a first actual
350 Call_Name := New_Occurrence_Of (Old_S, Loc);
351 Pref := Prefix (Nam);
354 Call_Name := New_Copy (Name (N));
357 -- Original name may have been overloaded, but is fully resolved now
359 Set_Is_Overloaded (Call_Name, False);
362 -- For simple renamings, subsequent calls can be expanded directly as
363 -- calls to the renamed entity. The body must be generated in any case
364 -- for calls that may appear elsewhere.
366 if Ekind_In (Old_S, E_Function, E_Procedure)
367 and then Nkind (Decl) = N_Subprogram_Declaration
369 Set_Body_To_Inline (Decl, Old_S);
372 -- The body generated for this renaming is an internal artifact, and
373 -- does not constitute a freeze point for the called entity.
375 Set_Must_Not_Freeze (Call_Name);
377 Formal := First_Formal (Defining_Entity (Decl));
379 if Present (Pref) then
381 Pref_Type : constant Entity_Id := Etype (Pref);
382 Form_Type : constant Entity_Id := Etype (First_Formal (Old_S));
385 -- The controlling formal may be an access parameter, or the
386 -- actual may be an access value, so adjust accordingly.
388 if Is_Access_Type (Pref_Type)
389 and then not Is_Access_Type (Form_Type)
392 (Make_Explicit_Dereference (Loc, Relocate_Node (Pref)));
394 elsif Is_Access_Type (Form_Type)
395 and then not Is_Access_Type (Pref)
398 (Make_Attribute_Reference (Loc,
399 Attribute_Name => Name_Access,
400 Prefix => Relocate_Node (Pref)));
402 Actuals := New_List (Pref);
406 elsif Present (Formal) then
413 if Present (Formal) then
414 while Present (Formal) loop
415 Append (New_Reference_To (Formal, Loc), Actuals);
416 Next_Formal (Formal);
420 -- If the renamed entity is an entry, inherit its profile. For other
421 -- renamings as bodies, both profiles must be subtype conformant, so it
422 -- is not necessary to replace the profile given in the declaration.
423 -- However, default values that are aggregates are rewritten when
424 -- partially analyzed, so we recover the original aggregate to insure
425 -- that subsequent conformity checking works. Similarly, if the default
426 -- expression was constant-folded, recover the original expression.
428 Formal := First_Formal (Defining_Entity (Decl));
430 if Present (Formal) then
431 O_Formal := First_Formal (Old_S);
432 Param_Spec := First (Parameter_Specifications (Spec));
433 while Present (Formal) loop
434 if Is_Entry (Old_S) then
435 if Nkind (Parameter_Type (Param_Spec)) /=
438 Set_Etype (Formal, Etype (O_Formal));
439 Set_Entity (Parameter_Type (Param_Spec), Etype (O_Formal));
442 elsif Nkind (Default_Value (O_Formal)) = N_Aggregate
443 or else Nkind (Original_Node (Default_Value (O_Formal))) /=
444 Nkind (Default_Value (O_Formal))
446 Set_Expression (Param_Spec,
447 New_Copy_Tree (Original_Node (Default_Value (O_Formal))));
450 Next_Formal (Formal);
451 Next_Formal (O_Formal);
456 -- If the renamed entity is a function, the generated body contains a
457 -- return statement. Otherwise, build a procedure call. If the entity is
458 -- an entry, subsequent analysis of the call will transform it into the
459 -- proper entry or protected operation call. If the renamed entity is
460 -- a character literal, return it directly.
462 if Ekind (Old_S) = E_Function
463 or else Ekind (Old_S) = E_Operator
464 or else (Ekind (Old_S) = E_Subprogram_Type
465 and then Etype (Old_S) /= Standard_Void_Type)
468 Make_Simple_Return_Statement (Loc,
470 Make_Function_Call (Loc,
472 Parameter_Associations => Actuals));
474 elsif Ekind (Old_S) = E_Enumeration_Literal then
476 Make_Simple_Return_Statement (Loc,
477 Expression => New_Occurrence_Of (Old_S, Loc));
479 elsif Nkind (Nam) = N_Character_Literal then
481 Make_Simple_Return_Statement (Loc,
482 Expression => Call_Name);
486 Make_Procedure_Call_Statement (Loc,
488 Parameter_Associations => Actuals);
491 -- Create entities for subprogram body and formals
493 Set_Defining_Unit_Name (Spec,
494 Make_Defining_Identifier (Loc, Chars => Chars (New_S)));
496 Param_Spec := First (Parameter_Specifications (Spec));
497 while Present (Param_Spec) loop
498 Set_Defining_Identifier (Param_Spec,
499 Make_Defining_Identifier (Loc,
500 Chars => Chars (Defining_Identifier (Param_Spec))));
505 Make_Subprogram_Body (Loc,
506 Specification => Spec,
507 Declarations => New_List,
508 Handled_Statement_Sequence =>
509 Make_Handled_Sequence_Of_Statements (Loc,
510 Statements => New_List (Call_Node)));
512 if Nkind (Decl) /= N_Subprogram_Declaration then
514 Make_Subprogram_Declaration (Loc,
515 Specification => Specification (N)));
518 -- Link the body to the entity whose declaration it completes. If
519 -- the body is analyzed when the renamed entity is frozen, it may
520 -- be necessary to restore the proper scope (see package Exp_Ch13).
522 if Nkind (N) = N_Subprogram_Renaming_Declaration
523 and then Present (Corresponding_Spec (N))
525 Set_Corresponding_Spec (Body_Node, Corresponding_Spec (N));
527 Set_Corresponding_Spec (Body_Node, New_S);
531 end Build_Renamed_Body;
533 --------------------------
534 -- Check_Address_Clause --
535 --------------------------
537 procedure Check_Address_Clause (E : Entity_Id) is
538 Addr : constant Node_Id := Address_Clause (E);
540 Decl : constant Node_Id := Declaration_Node (E);
541 Typ : constant Entity_Id := Etype (E);
544 if Present (Addr) then
545 Expr := Expression (Addr);
547 -- If we have no initialization of any kind, then we don't need to
548 -- place any restrictions on the address clause, because the object
549 -- will be elaborated after the address clause is evaluated. This
550 -- happens if the declaration has no initial expression, or the type
551 -- has no implicit initialization, or the object is imported.
553 -- The same holds for all initialized scalar types and all access
554 -- types. Packed bit arrays of size up to 64 are represented using a
555 -- modular type with an initialization (to zero) and can be processed
556 -- like other initialized scalar types.
558 -- If the type is controlled, code to attach the object to a
559 -- finalization chain is generated at the point of declaration,
560 -- and therefore the elaboration of the object cannot be delayed:
561 -- the address expression must be a constant.
563 if (No (Expression (Decl))
564 and then not Needs_Finalization (Typ)
565 and then (not Has_Non_Null_Base_Init_Proc (Typ)
566 or else Is_Imported (E)))
567 or else (Present (Expression (Decl)) and then Is_Scalar_Type (Typ))
568 or else Is_Access_Type (Typ)
570 (Is_Bit_Packed_Array (Typ)
571 and then Is_Modular_Integer_Type (Packed_Array_Type (Typ)))
575 -- Otherwise, we require the address clause to be constant because
576 -- the call to the initialization procedure (or the attach code) has
577 -- to happen at the point of the declaration.
579 -- Actually the IP call has been moved to the freeze actions
580 -- anyway, so maybe we can relax this restriction???
583 Check_Constant_Address_Clause (Expr, E);
585 -- Has_Delayed_Freeze was set on E when the address clause was
586 -- analyzed. Reset the flag now unless freeze actions were
587 -- attached to it in the mean time.
589 if No (Freeze_Node (E)) then
590 Set_Has_Delayed_Freeze (E, False);
594 if not Error_Posted (Expr)
595 and then not Needs_Finalization (Typ)
597 Warn_Overlay (Expr, Typ, Name (Addr));
600 end Check_Address_Clause;
602 -----------------------------
603 -- Check_Compile_Time_Size --
604 -----------------------------
606 procedure Check_Compile_Time_Size (T : Entity_Id) is
608 procedure Set_Small_Size (T : Entity_Id; S : Uint);
609 -- Sets the compile time known size (32 bits or less) in the Esize
610 -- field, of T checking for a size clause that was given which attempts
611 -- to give a smaller size, and also checking for an alignment clause.
613 function Size_Known (T : Entity_Id) return Boolean;
614 -- Recursive function that does all the work
616 function Static_Discriminated_Components (T : Entity_Id) return Boolean;
617 -- If T is a constrained subtype, its size is not known if any of its
618 -- discriminant constraints is not static and it is not a null record.
619 -- The test is conservative and doesn't check that the components are
620 -- in fact constrained by non-static discriminant values. Could be made
627 procedure Set_Small_Size (T : Entity_Id; S : Uint) is
632 -- Don't bother if alignment clause with a value other than 1 is
633 -- present, because size may be padded up to meet back end alignment
634 -- requirements, and only the back end knows the rules!
636 elsif Known_Alignment (T) and then Alignment (T) /= 1 then
639 -- Check for bad size clause given
641 elsif Has_Size_Clause (T) then
642 if RM_Size (T) < S then
643 Error_Msg_Uint_1 := S;
645 ("size for& too small, minimum allowed is ^",
648 elsif Unknown_Esize (T) then
652 -- Set sizes if not set already
655 if Unknown_Esize (T) then
659 if Unknown_RM_Size (T) then
669 function Size_Known (T : Entity_Id) return Boolean is
677 if Size_Known_At_Compile_Time (T) then
680 -- Always True for scalar types. This is true even for generic formal
681 -- scalar types. We used to return False in the latter case, but the
682 -- size is known at compile time, even in the template, we just do
683 -- not know the exact size but that's not the point of this routine.
685 elsif Is_Scalar_Type (T)
686 or else Is_Task_Type (T)
692 elsif Is_Array_Type (T) then
694 -- String literals always have known size, and we can set it
696 if Ekind (T) = E_String_Literal_Subtype then
697 Set_Small_Size (T, Component_Size (T)
698 * String_Literal_Length (T));
701 -- Unconstrained types never have known at compile time size
703 elsif not Is_Constrained (T) then
706 -- Don't do any recursion on type with error posted, since we may
707 -- have a malformed type that leads us into a loop.
709 elsif Error_Posted (T) then
712 -- Otherwise if component size unknown, then array size unknown
714 elsif not Size_Known (Component_Type (T)) then
718 -- Check for all indexes static, and also compute possible size
719 -- (in case it is less than 32 and may be packable).
722 Esiz : Uint := Component_Size (T);
726 Index := First_Index (T);
727 while Present (Index) loop
728 if Nkind (Index) = N_Range then
729 Get_Index_Bounds (Index, Low, High);
731 elsif Error_Posted (Scalar_Range (Etype (Index))) then
735 Low := Type_Low_Bound (Etype (Index));
736 High := Type_High_Bound (Etype (Index));
739 if not Compile_Time_Known_Value (Low)
740 or else not Compile_Time_Known_Value (High)
741 or else Etype (Index) = Any_Type
746 Dim := Expr_Value (High) - Expr_Value (Low) + 1;
758 Set_Small_Size (T, Esiz);
762 -- Access types always have known at compile time sizes
764 elsif Is_Access_Type (T) then
767 -- For non-generic private types, go to underlying type if present
769 elsif Is_Private_Type (T)
770 and then not Is_Generic_Type (T)
771 and then Present (Underlying_Type (T))
773 -- Don't do any recursion on type with error posted, since we may
774 -- have a malformed type that leads us into a loop.
776 if Error_Posted (T) then
779 return Size_Known (Underlying_Type (T));
784 elsif Is_Record_Type (T) then
786 -- A class-wide type is never considered to have a known size
788 if Is_Class_Wide_Type (T) then
791 -- A subtype of a variant record must not have non-static
792 -- discriminanted components.
794 elsif T /= Base_Type (T)
795 and then not Static_Discriminated_Components (T)
799 -- Don't do any recursion on type with error posted, since we may
800 -- have a malformed type that leads us into a loop.
802 elsif Error_Posted (T) then
806 -- Now look at the components of the record
809 -- The following two variables are used to keep track of the
810 -- size of packed records if we can tell the size of the packed
811 -- record in the front end. Packed_Size_Known is True if so far
812 -- we can figure out the size. It is initialized to True for a
813 -- packed record, unless the record has discriminants. The
814 -- reason we eliminate the discriminated case is that we don't
815 -- know the way the back end lays out discriminated packed
816 -- records. If Packed_Size_Known is True, then Packed_Size is
817 -- the size in bits so far.
819 Packed_Size_Known : Boolean :=
821 and then not Has_Discriminants (T);
823 Packed_Size : Uint := Uint_0;
826 -- Test for variant part present
828 if Has_Discriminants (T)
829 and then Present (Parent (T))
830 and then Nkind (Parent (T)) = N_Full_Type_Declaration
831 and then Nkind (Type_Definition (Parent (T))) =
833 and then not Null_Present (Type_Definition (Parent (T)))
834 and then Present (Variant_Part
835 (Component_List (Type_Definition (Parent (T)))))
837 -- If variant part is present, and type is unconstrained,
838 -- then we must have defaulted discriminants, or a size
839 -- clause must be present for the type, or else the size
840 -- is definitely not known at compile time.
842 if not Is_Constrained (T)
844 No (Discriminant_Default_Value (First_Discriminant (T)))
845 and then Unknown_Esize (T)
851 -- Loop through components
853 Comp := First_Component_Or_Discriminant (T);
854 while Present (Comp) loop
855 Ctyp := Etype (Comp);
857 -- We do not know the packed size if there is a component
858 -- clause present (we possibly could, but this would only
859 -- help in the case of a record with partial rep clauses.
860 -- That's because in the case of full rep clauses, the
861 -- size gets figured out anyway by a different circuit).
863 if Present (Component_Clause (Comp)) then
864 Packed_Size_Known := False;
867 -- We need to identify a component that is an array where
868 -- the index type is an enumeration type with non-standard
869 -- representation, and some bound of the type depends on a
872 -- This is because gigi computes the size by doing a
873 -- substitution of the appropriate discriminant value in
874 -- the size expression for the base type, and gigi is not
875 -- clever enough to evaluate the resulting expression (which
876 -- involves a call to rep_to_pos) at compile time.
878 -- It would be nice if gigi would either recognize that
879 -- this expression can be computed at compile time, or
880 -- alternatively figured out the size from the subtype
881 -- directly, where all the information is at hand ???
883 if Is_Array_Type (Etype (Comp))
884 and then Present (Packed_Array_Type (Etype (Comp)))
887 Ocomp : constant Entity_Id :=
888 Original_Record_Component (Comp);
889 OCtyp : constant Entity_Id := Etype (Ocomp);
895 Ind := First_Index (OCtyp);
896 while Present (Ind) loop
897 Indtyp := Etype (Ind);
899 if Is_Enumeration_Type (Indtyp)
900 and then Has_Non_Standard_Rep (Indtyp)
902 Lo := Type_Low_Bound (Indtyp);
903 Hi := Type_High_Bound (Indtyp);
905 if Is_Entity_Name (Lo)
906 and then Ekind (Entity (Lo)) = E_Discriminant
910 elsif Is_Entity_Name (Hi)
911 and then Ekind (Entity (Hi)) = E_Discriminant
922 -- Clearly size of record is not known if the size of one of
923 -- the components is not known.
925 if not Size_Known (Ctyp) then
929 -- Accumulate packed size if possible
931 if Packed_Size_Known then
933 -- We can only deal with elementary types, since for
934 -- non-elementary components, alignment enters into the
935 -- picture, and we don't know enough to handle proper
936 -- alignment in this context. Packed arrays count as
937 -- elementary if the representation is a modular type.
939 if Is_Elementary_Type (Ctyp)
940 or else (Is_Array_Type (Ctyp)
941 and then Present (Packed_Array_Type (Ctyp))
942 and then Is_Modular_Integer_Type
943 (Packed_Array_Type (Ctyp)))
945 -- If RM_Size is known and static, then we can keep
946 -- accumulating the packed size.
948 if Known_Static_RM_Size (Ctyp) then
950 -- A little glitch, to be removed sometime ???
951 -- gigi does not understand zero sizes yet.
953 if RM_Size (Ctyp) = Uint_0 then
954 Packed_Size_Known := False;
956 -- Normal case where we can keep accumulating the
957 -- packed array size.
960 Packed_Size := Packed_Size + RM_Size (Ctyp);
963 -- If we have a field whose RM_Size is not known then
964 -- we can't figure out the packed size here.
967 Packed_Size_Known := False;
970 -- If we have a non-elementary type we can't figure out
971 -- the packed array size (alignment issues).
974 Packed_Size_Known := False;
978 Next_Component_Or_Discriminant (Comp);
981 if Packed_Size_Known then
982 Set_Small_Size (T, Packed_Size);
988 -- All other cases, size not known at compile time
995 -------------------------------------
996 -- Static_Discriminated_Components --
997 -------------------------------------
999 function Static_Discriminated_Components
1000 (T : Entity_Id) return Boolean
1002 Constraint : Elmt_Id;
1005 if Has_Discriminants (T)
1006 and then Present (Discriminant_Constraint (T))
1007 and then Present (First_Component (T))
1009 Constraint := First_Elmt (Discriminant_Constraint (T));
1010 while Present (Constraint) loop
1011 if not Compile_Time_Known_Value (Node (Constraint)) then
1015 Next_Elmt (Constraint);
1020 end Static_Discriminated_Components;
1022 -- Start of processing for Check_Compile_Time_Size
1025 Set_Size_Known_At_Compile_Time (T, Size_Known (T));
1026 end Check_Compile_Time_Size;
1028 -----------------------------
1029 -- Check_Debug_Info_Needed --
1030 -----------------------------
1032 procedure Check_Debug_Info_Needed (T : Entity_Id) is
1034 if Debug_Info_Off (T) then
1037 elsif Comes_From_Source (T)
1038 or else Debug_Generated_Code
1039 or else Debug_Flag_VV
1040 or else Needs_Debug_Info (T)
1042 Set_Debug_Info_Needed (T);
1044 end Check_Debug_Info_Needed;
1046 ----------------------------
1047 -- Check_Strict_Alignment --
1048 ----------------------------
1050 procedure Check_Strict_Alignment (E : Entity_Id) is
1054 if Is_Tagged_Type (E) or else Is_Concurrent_Type (E) then
1055 Set_Strict_Alignment (E);
1057 elsif Is_Array_Type (E) then
1058 Set_Strict_Alignment (E, Strict_Alignment (Component_Type (E)));
1060 elsif Is_Record_Type (E) then
1061 if Is_Limited_Record (E) then
1062 Set_Strict_Alignment (E);
1066 Comp := First_Component (E);
1068 while Present (Comp) loop
1069 if not Is_Type (Comp)
1070 and then (Strict_Alignment (Etype (Comp))
1071 or else Is_Aliased (Comp))
1073 Set_Strict_Alignment (E);
1077 Next_Component (Comp);
1080 end Check_Strict_Alignment;
1082 -------------------------
1083 -- Check_Unsigned_Type --
1084 -------------------------
1086 procedure Check_Unsigned_Type (E : Entity_Id) is
1087 Ancestor : Entity_Id;
1092 if not Is_Discrete_Or_Fixed_Point_Type (E) then
1096 -- Do not attempt to analyze case where range was in error
1098 if Error_Posted (Scalar_Range (E)) then
1102 -- The situation that is non trivial is something like
1104 -- subtype x1 is integer range -10 .. +10;
1105 -- subtype x2 is x1 range 0 .. V1;
1106 -- subtype x3 is x2 range V2 .. V3;
1107 -- subtype x4 is x3 range V4 .. V5;
1109 -- where Vn are variables. Here the base type is signed, but we still
1110 -- know that x4 is unsigned because of the lower bound of x2.
1112 -- The only way to deal with this is to look up the ancestor chain
1116 if Ancestor = Any_Type or else Etype (Ancestor) = Any_Type then
1120 Lo_Bound := Type_Low_Bound (Ancestor);
1122 if Compile_Time_Known_Value (Lo_Bound) then
1124 if Expr_Rep_Value (Lo_Bound) >= 0 then
1125 Set_Is_Unsigned_Type (E, True);
1131 Ancestor := Ancestor_Subtype (Ancestor);
1133 -- If no ancestor had a static lower bound, go to base type
1135 if No (Ancestor) then
1137 -- Note: the reason we still check for a compile time known
1138 -- value for the base type is that at least in the case of
1139 -- generic formals, we can have bounds that fail this test,
1140 -- and there may be other cases in error situations.
1142 Btyp := Base_Type (E);
1144 if Btyp = Any_Type or else Etype (Btyp) = Any_Type then
1148 Lo_Bound := Type_Low_Bound (Base_Type (E));
1150 if Compile_Time_Known_Value (Lo_Bound)
1151 and then Expr_Rep_Value (Lo_Bound) >= 0
1153 Set_Is_Unsigned_Type (E, True);
1160 end Check_Unsigned_Type;
1162 -------------------------
1163 -- Is_Atomic_Aggregate --
1164 -------------------------
1166 function Is_Atomic_Aggregate
1168 Typ : Entity_Id) return Boolean
1170 Loc : constant Source_Ptr := Sloc (E);
1178 -- Array may be qualified, so find outer context
1180 if Nkind (Par) = N_Qualified_Expression then
1181 Par := Parent (Par);
1184 if Nkind_In (Par, N_Object_Declaration, N_Assignment_Statement)
1185 and then Comes_From_Source (Par)
1187 Temp := Make_Temporary (Loc, 'T', E);
1189 Make_Object_Declaration (Loc,
1190 Defining_Identifier => Temp,
1191 Object_Definition => New_Occurrence_Of (Typ, Loc),
1192 Expression => Relocate_Node (E));
1193 Insert_Before (Par, New_N);
1196 Set_Expression (Par, New_Occurrence_Of (Temp, Loc));
1202 end Is_Atomic_Aggregate;
1208 -- Note: the easy coding for this procedure would be to just build a
1209 -- single list of freeze nodes and then insert them and analyze them
1210 -- all at once. This won't work, because the analysis of earlier freeze
1211 -- nodes may recursively freeze types which would otherwise appear later
1212 -- on in the freeze list. So we must analyze and expand the freeze nodes
1213 -- as they are generated.
1215 procedure Freeze_All (From : Entity_Id; After : in out Node_Id) is
1216 Loc : constant Source_Ptr := Sloc (After);
1220 procedure Freeze_All_Ent (From : Entity_Id; After : in out Node_Id);
1221 -- This is the internal recursive routine that does freezing of entities
1222 -- (but NOT the analysis of default expressions, which should not be
1223 -- recursive, we don't want to analyze those till we are sure that ALL
1224 -- the types are frozen).
1226 --------------------
1227 -- Freeze_All_Ent --
1228 --------------------
1230 procedure Freeze_All_Ent (From : Entity_Id; After : in out Node_Id) is
1235 procedure Process_Flist;
1236 -- If freeze nodes are present, insert and analyze, and reset cursor
1237 -- for next insertion.
1243 procedure Process_Flist is
1245 if Is_Non_Empty_List (Flist) then
1246 Lastn := Next (After);
1247 Insert_List_After_And_Analyze (After, Flist);
1249 if Present (Lastn) then
1250 After := Prev (Lastn);
1252 After := Last (List_Containing (After));
1257 -- Start or processing for Freeze_All_Ent
1261 while Present (E) loop
1263 -- If the entity is an inner package which is not a package
1264 -- renaming, then its entities must be frozen at this point. Note
1265 -- that such entities do NOT get frozen at the end of the nested
1266 -- package itself (only library packages freeze).
1268 -- Same is true for task declarations, where anonymous records
1269 -- created for entry parameters must be frozen.
1271 if Ekind (E) = E_Package
1272 and then No (Renamed_Object (E))
1273 and then not Is_Child_Unit (E)
1274 and then not Is_Frozen (E)
1277 Install_Visible_Declarations (E);
1278 Install_Private_Declarations (E);
1280 Freeze_All (First_Entity (E), After);
1282 End_Package_Scope (E);
1284 elsif Ekind (E) in Task_Kind
1286 (Nkind (Parent (E)) = N_Task_Type_Declaration
1288 Nkind (Parent (E)) = N_Single_Task_Declaration)
1291 Freeze_All (First_Entity (E), After);
1294 -- For a derived tagged type, we must ensure that all the
1295 -- primitive operations of the parent have been frozen, so that
1296 -- their addresses will be in the parent's dispatch table at the
1297 -- point it is inherited.
1299 elsif Ekind (E) = E_Record_Type
1300 and then Is_Tagged_Type (E)
1301 and then Is_Tagged_Type (Etype (E))
1302 and then Is_Derived_Type (E)
1305 Prim_List : constant Elist_Id :=
1306 Primitive_Operations (Etype (E));
1312 Prim := First_Elmt (Prim_List);
1313 while Present (Prim) loop
1314 Subp := Node (Prim);
1316 if Comes_From_Source (Subp)
1317 and then not Is_Frozen (Subp)
1319 Flist := Freeze_Entity (Subp, Loc);
1328 if not Is_Frozen (E) then
1329 Flist := Freeze_Entity (E, Loc);
1333 -- If an incomplete type is still not frozen, this may be a
1334 -- premature freezing because of a body declaration that follows.
1335 -- Indicate where the freezing took place.
1337 -- If the freezing is caused by the end of the current declarative
1338 -- part, it is a Taft Amendment type, and there is no error.
1340 if not Is_Frozen (E)
1341 and then Ekind (E) = E_Incomplete_Type
1344 Bod : constant Node_Id := Next (After);
1347 if (Nkind_In (Bod, N_Subprogram_Body,
1352 or else Nkind (Bod) in N_Body_Stub)
1354 List_Containing (After) = List_Containing (Parent (E))
1356 Error_Msg_Sloc := Sloc (Next (After));
1358 ("type& is frozen# before its full declaration",
1368 -- Start of processing for Freeze_All
1371 Freeze_All_Ent (From, After);
1373 -- Now that all types are frozen, we can deal with default expressions
1374 -- that require us to build a default expression functions. This is the
1375 -- point at which such functions are constructed (after all types that
1376 -- might be used in such expressions have been frozen).
1378 -- For subprograms that are renaming_as_body, we create the wrapper
1379 -- bodies as needed.
1381 -- We also add finalization chains to access types whose designated
1382 -- types are controlled. This is normally done when freezing the type,
1383 -- but this misses recursive type definitions where the later members
1384 -- of the recursion introduce controlled components.
1386 -- Loop through entities
1389 while Present (E) loop
1390 if Is_Subprogram (E) then
1392 if not Default_Expressions_Processed (E) then
1393 Process_Default_Expressions (E, After);
1396 if not Has_Completion (E) then
1397 Decl := Unit_Declaration_Node (E);
1399 if Nkind (Decl) = N_Subprogram_Renaming_Declaration then
1400 Build_And_Analyze_Renamed_Body (Decl, E, After);
1402 elsif Nkind (Decl) = N_Subprogram_Declaration
1403 and then Present (Corresponding_Body (Decl))
1405 Nkind (Unit_Declaration_Node (Corresponding_Body (Decl)))
1406 = N_Subprogram_Renaming_Declaration
1408 Build_And_Analyze_Renamed_Body
1409 (Decl, Corresponding_Body (Decl), After);
1413 elsif Ekind (E) in Task_Kind
1415 (Nkind (Parent (E)) = N_Task_Type_Declaration
1417 Nkind (Parent (E)) = N_Single_Task_Declaration)
1423 Ent := First_Entity (E);
1424 while Present (Ent) loop
1426 and then not Default_Expressions_Processed (Ent)
1428 Process_Default_Expressions (Ent, After);
1435 elsif Is_Access_Type (E)
1436 and then Comes_From_Source (E)
1437 and then Ekind (Directly_Designated_Type (E)) = E_Incomplete_Type
1438 and then Needs_Finalization (Designated_Type (E))
1439 and then No (Associated_Final_Chain (E))
1441 Build_Final_List (Parent (E), E);
1448 -----------------------
1449 -- Freeze_And_Append --
1450 -----------------------
1452 procedure Freeze_And_Append
1455 Result : in out List_Id)
1457 L : constant List_Id := Freeze_Entity (Ent, Loc);
1459 if Is_Non_Empty_List (L) then
1460 if Result = No_List then
1463 Append_List (L, Result);
1466 end Freeze_And_Append;
1472 procedure Freeze_Before (N : Node_Id; T : Entity_Id) is
1473 Freeze_Nodes : constant List_Id := Freeze_Entity (T, Sloc (N));
1475 if Is_Non_Empty_List (Freeze_Nodes) then
1476 Insert_Actions (N, Freeze_Nodes);
1484 function Freeze_Entity (E : Entity_Id; Loc : Source_Ptr) return List_Id is
1485 Test_E : Entity_Id := E;
1493 Has_Default_Initialization : Boolean := False;
1494 -- This flag gets set to true for a variable with default initialization
1496 procedure Check_Current_Instance (Comp_Decl : Node_Id);
1497 -- Check that an Access or Unchecked_Access attribute with a prefix
1498 -- which is the current instance type can only be applied when the type
1501 procedure Check_Suspicious_Modulus (Utype : Entity_Id);
1502 -- Give warning for modulus of 8, 16, 32, or 64 given as an explicit
1503 -- integer literal without an explicit corresponding size clause. The
1504 -- caller has checked that Utype is a modular integer type.
1506 function After_Last_Declaration return Boolean;
1507 -- If Loc is a freeze_entity that appears after the last declaration
1508 -- in the scope, inhibit error messages on late completion.
1510 procedure Freeze_Record_Type (Rec : Entity_Id);
1511 -- Freeze each component, handle some representation clauses, and freeze
1512 -- primitive operations if this is a tagged type.
1514 ----------------------------
1515 -- After_Last_Declaration --
1516 ----------------------------
1518 function After_Last_Declaration return Boolean is
1519 Spec : constant Node_Id := Parent (Current_Scope);
1521 if Nkind (Spec) = N_Package_Specification then
1522 if Present (Private_Declarations (Spec)) then
1523 return Loc >= Sloc (Last (Private_Declarations (Spec)));
1524 elsif Present (Visible_Declarations (Spec)) then
1525 return Loc >= Sloc (Last (Visible_Declarations (Spec)));
1532 end After_Last_Declaration;
1534 ----------------------------
1535 -- Check_Current_Instance --
1536 ----------------------------
1538 procedure Check_Current_Instance (Comp_Decl : Node_Id) is
1540 Rec_Type : constant Entity_Id :=
1541 Scope (Defining_Identifier (Comp_Decl));
1543 Decl : constant Node_Id := Parent (Rec_Type);
1545 function Process (N : Node_Id) return Traverse_Result;
1546 -- Process routine to apply check to given node
1552 function Process (N : Node_Id) return Traverse_Result is
1555 when N_Attribute_Reference =>
1556 if (Attribute_Name (N) = Name_Access
1558 Attribute_Name (N) = Name_Unchecked_Access)
1559 and then Is_Entity_Name (Prefix (N))
1560 and then Is_Type (Entity (Prefix (N)))
1561 and then Entity (Prefix (N)) = E
1564 ("current instance must be a limited type", Prefix (N));
1570 when others => return OK;
1574 procedure Traverse is new Traverse_Proc (Process);
1576 -- Start of processing for Check_Current_Instance
1579 -- In Ada95, the (imprecise) rule is that the current instance of a
1580 -- limited type is aliased. In Ada2005, limitedness must be explicit:
1581 -- either a tagged type, or a limited record.
1583 if Is_Limited_Type (Rec_Type)
1584 and then (Ada_Version < Ada_05 or else Is_Tagged_Type (Rec_Type))
1588 elsif Nkind (Decl) = N_Full_Type_Declaration
1589 and then Limited_Present (Type_Definition (Decl))
1594 Traverse (Comp_Decl);
1596 end Check_Current_Instance;
1598 ------------------------------
1599 -- Check_Suspicious_Modulus --
1600 ------------------------------
1602 procedure Check_Suspicious_Modulus (Utype : Entity_Id) is
1603 Decl : constant Node_Id := Declaration_Node (Underlying_Type (Utype));
1606 if Nkind (Decl) = N_Full_Type_Declaration then
1608 Tdef : constant Node_Id := Type_Definition (Decl);
1610 if Nkind (Tdef) = N_Modular_Type_Definition then
1612 Modulus : constant Node_Id :=
1613 Original_Node (Expression (Tdef));
1615 if Nkind (Modulus) = N_Integer_Literal then
1617 Modv : constant Uint := Intval (Modulus);
1618 Sizv : constant Uint := RM_Size (Utype);
1621 -- First case, modulus and size are the same. This
1622 -- happens if you have something like mod 32, with
1623 -- an explicit size of 32, this is for sure a case
1624 -- where the warning is given, since it is seems
1625 -- very unlikely that someone would want e.g. a
1626 -- five bit type stored in 32 bits. It is much
1627 -- more likely they wanted a 32-bit type.
1632 -- Second case, the modulus is 32 or 64 and no
1633 -- size clause is present. This is a less clear
1634 -- case for giving the warning, but in the case
1635 -- of 32/64 (5-bit or 6-bit types) these seem rare
1636 -- enough that it is a likely error (and in any
1637 -- case using 2**5 or 2**6 in these cases seems
1638 -- clearer. We don't include 8 or 16 here, simply
1639 -- because in practice 3-bit and 4-bit types are
1640 -- more common and too many false positives if
1641 -- we warn in these cases.
1643 elsif not Has_Size_Clause (Utype)
1644 and then (Modv = Uint_32 or else Modv = Uint_64)
1648 -- No warning needed
1654 -- If we fall through, give warning
1656 Error_Msg_Uint_1 := Modv;
1658 ("?2 '*'*^' may have been intended here",
1666 end Check_Suspicious_Modulus;
1668 ------------------------
1669 -- Freeze_Record_Type --
1670 ------------------------
1672 procedure Freeze_Record_Type (Rec : Entity_Id) is
1679 pragma Warnings (Off, Junk);
1681 Unplaced_Component : Boolean := False;
1682 -- Set True if we find at least one component with no component
1683 -- clause (used to warn about useless Pack pragmas).
1685 Placed_Component : Boolean := False;
1686 -- Set True if we find at least one component with a component
1687 -- clause (used to warn about useless Bit_Order pragmas, and also
1688 -- to detect cases where Implicit_Packing may have an effect).
1690 All_Scalar_Components : Boolean := True;
1691 -- Set False if we encounter a component of a non-scalar type
1693 Scalar_Component_Total_RM_Size : Uint := Uint_0;
1694 Scalar_Component_Total_Esize : Uint := Uint_0;
1695 -- Accumulates total RM_Size values and total Esize values of all
1696 -- scalar components. Used for processing of Implicit_Packing.
1698 function Check_Allocator (N : Node_Id) return Node_Id;
1699 -- If N is an allocator, possibly wrapped in one or more level of
1700 -- qualified expression(s), return the inner allocator node, else
1703 procedure Check_Itype (Typ : Entity_Id);
1704 -- If the component subtype is an access to a constrained subtype of
1705 -- an already frozen type, make the subtype frozen as well. It might
1706 -- otherwise be frozen in the wrong scope, and a freeze node on
1707 -- subtype has no effect. Similarly, if the component subtype is a
1708 -- regular (not protected) access to subprogram, set the anonymous
1709 -- subprogram type to frozen as well, to prevent an out-of-scope
1710 -- freeze node at some eventual point of call. Protected operations
1711 -- are handled elsewhere.
1713 ---------------------
1714 -- Check_Allocator --
1715 ---------------------
1717 function Check_Allocator (N : Node_Id) return Node_Id is
1722 if Nkind (Inner) = N_Allocator then
1724 elsif Nkind (Inner) = N_Qualified_Expression then
1725 Inner := Expression (Inner);
1730 end Check_Allocator;
1736 procedure Check_Itype (Typ : Entity_Id) is
1737 Desig : constant Entity_Id := Designated_Type (Typ);
1740 if not Is_Frozen (Desig)
1741 and then Is_Frozen (Base_Type (Desig))
1743 Set_Is_Frozen (Desig);
1745 -- In addition, add an Itype_Reference to ensure that the
1746 -- access subtype is elaborated early enough. This cannot be
1747 -- done if the subtype may depend on discriminants.
1749 if Ekind (Comp) = E_Component
1750 and then Is_Itype (Etype (Comp))
1751 and then not Has_Discriminants (Rec)
1753 IR := Make_Itype_Reference (Sloc (Comp));
1754 Set_Itype (IR, Desig);
1757 Result := New_List (IR);
1759 Append (IR, Result);
1763 elsif Ekind (Typ) = E_Anonymous_Access_Subprogram_Type
1764 and then Convention (Desig) /= Convention_Protected
1766 Set_Is_Frozen (Desig);
1770 -- Start of processing for Freeze_Record_Type
1773 -- If this is a subtype of a controlled type, declared without a
1774 -- constraint, the _controller may not appear in the component list
1775 -- if the parent was not frozen at the point of subtype declaration.
1776 -- Inherit the _controller component now.
1778 if Rec /= Base_Type (Rec)
1779 and then Has_Controlled_Component (Rec)
1781 if Nkind (Parent (Rec)) = N_Subtype_Declaration
1782 and then Is_Entity_Name (Subtype_Indication (Parent (Rec)))
1784 Set_First_Entity (Rec, First_Entity (Base_Type (Rec)));
1786 -- If this is an internal type without a declaration, as for
1787 -- record component, the base type may not yet be frozen, and its
1788 -- controller has not been created. Add an explicit freeze node
1789 -- for the itype, so it will be frozen after the base type. This
1790 -- freeze node is used to communicate with the expander, in order
1791 -- to create the controller for the enclosing record, and it is
1792 -- deleted afterwards (see exp_ch3). It must not be created when
1793 -- expansion is off, because it might appear in the wrong context
1794 -- for the back end.
1796 elsif Is_Itype (Rec)
1797 and then Has_Delayed_Freeze (Base_Type (Rec))
1799 Nkind (Associated_Node_For_Itype (Rec)) =
1800 N_Component_Declaration
1801 and then Expander_Active
1803 Ensure_Freeze_Node (Rec);
1807 -- Freeze components and embedded subtypes
1809 Comp := First_Entity (Rec);
1811 while Present (Comp) loop
1813 -- First handle the component case
1815 if Ekind (Comp) = E_Component
1816 or else Ekind (Comp) = E_Discriminant
1819 CC : constant Node_Id := Component_Clause (Comp);
1822 -- Freezing a record type freezes the type of each of its
1823 -- components. However, if the type of the component is
1824 -- part of this record, we do not want or need a separate
1825 -- Freeze_Node. Note that Is_Itype is wrong because that's
1826 -- also set in private type cases. We also can't check for
1827 -- the Scope being exactly Rec because of private types and
1828 -- record extensions.
1830 if Is_Itype (Etype (Comp))
1831 and then Is_Record_Type (Underlying_Type
1832 (Scope (Etype (Comp))))
1834 Undelay_Type (Etype (Comp));
1837 Freeze_And_Append (Etype (Comp), Loc, Result);
1839 -- Check for error of component clause given for variable
1840 -- sized type. We have to delay this test till this point,
1841 -- since the component type has to be frozen for us to know
1842 -- if it is variable length. We omit this test in a generic
1843 -- context, it will be applied at instantiation time.
1845 if Present (CC) then
1846 Placed_Component := True;
1848 if Inside_A_Generic then
1852 Size_Known_At_Compile_Time
1853 (Underlying_Type (Etype (Comp)))
1856 ("component clause not allowed for variable " &
1857 "length component", CC);
1861 Unplaced_Component := True;
1864 -- Case of component requires byte alignment
1866 if Must_Be_On_Byte_Boundary (Etype (Comp)) then
1868 -- Set the enclosing record to also require byte align
1870 Set_Must_Be_On_Byte_Boundary (Rec);
1872 -- Check for component clause that is inconsistent with
1873 -- the required byte boundary alignment.
1876 and then Normalized_First_Bit (Comp) mod
1877 System_Storage_Unit /= 0
1880 ("component & must be byte aligned",
1881 Component_Name (Component_Clause (Comp)));
1887 -- Gather data for possible Implicit_Packing later. Note that at
1888 -- this stage we might be dealing with a real component, or with
1889 -- an implicit subtype declaration.
1891 if not Is_Scalar_Type (Etype (Comp)) then
1892 All_Scalar_Components := False;
1894 Scalar_Component_Total_RM_Size :=
1895 Scalar_Component_Total_RM_Size + RM_Size (Etype (Comp));
1896 Scalar_Component_Total_Esize :=
1897 Scalar_Component_Total_Esize + Esize (Etype (Comp));
1900 -- If the component is an Itype with Delayed_Freeze and is either
1901 -- a record or array subtype and its base type has not yet been
1902 -- frozen, we must remove this from the entity list of this record
1903 -- and put it on the entity list of the scope of its base type.
1904 -- Note that we know that this is not the type of a component
1905 -- since we cleared Has_Delayed_Freeze for it in the previous
1906 -- loop. Thus this must be the Designated_Type of an access type,
1907 -- which is the type of a component.
1910 and then Is_Type (Scope (Comp))
1911 and then Is_Composite_Type (Comp)
1912 and then Base_Type (Comp) /= Comp
1913 and then Has_Delayed_Freeze (Comp)
1914 and then not Is_Frozen (Base_Type (Comp))
1917 Will_Be_Frozen : Boolean := False;
1921 -- We have a pretty bad kludge here. Suppose Rec is subtype
1922 -- being defined in a subprogram that's created as part of
1923 -- the freezing of Rec'Base. In that case, we know that
1924 -- Comp'Base must have already been frozen by the time we
1925 -- get to elaborate this because Gigi doesn't elaborate any
1926 -- bodies until it has elaborated all of the declarative
1927 -- part. But Is_Frozen will not be set at this point because
1928 -- we are processing code in lexical order.
1930 -- We detect this case by going up the Scope chain of Rec
1931 -- and seeing if we have a subprogram scope before reaching
1932 -- the top of the scope chain or that of Comp'Base. If we
1933 -- do, then mark that Comp'Base will actually be frozen. If
1934 -- so, we merely undelay it.
1937 while Present (S) loop
1938 if Is_Subprogram (S) then
1939 Will_Be_Frozen := True;
1941 elsif S = Scope (Base_Type (Comp)) then
1948 if Will_Be_Frozen then
1949 Undelay_Type (Comp);
1951 if Present (Prev) then
1952 Set_Next_Entity (Prev, Next_Entity (Comp));
1954 Set_First_Entity (Rec, Next_Entity (Comp));
1957 -- Insert in entity list of scope of base type (which
1958 -- must be an enclosing scope, because still unfrozen).
1960 Append_Entity (Comp, Scope (Base_Type (Comp)));
1964 -- If the component is an access type with an allocator as default
1965 -- value, the designated type will be frozen by the corresponding
1966 -- expression in init_proc. In order to place the freeze node for
1967 -- the designated type before that for the current record type,
1970 -- Same process if the component is an array of access types,
1971 -- initialized with an aggregate. If the designated type is
1972 -- private, it cannot contain allocators, and it is premature
1973 -- to freeze the type, so we check for this as well.
1975 elsif Is_Access_Type (Etype (Comp))
1976 and then Present (Parent (Comp))
1977 and then Present (Expression (Parent (Comp)))
1980 Alloc : constant Node_Id :=
1981 Check_Allocator (Expression (Parent (Comp)));
1984 if Present (Alloc) then
1986 -- If component is pointer to a classwide type, freeze
1987 -- the specific type in the expression being allocated.
1988 -- The expression may be a subtype indication, in which
1989 -- case freeze the subtype mark.
1991 if Is_Class_Wide_Type
1992 (Designated_Type (Etype (Comp)))
1994 if Is_Entity_Name (Expression (Alloc)) then
1996 (Entity (Expression (Alloc)), Loc, Result);
1998 Nkind (Expression (Alloc)) = N_Subtype_Indication
2001 (Entity (Subtype_Mark (Expression (Alloc))),
2005 elsif Is_Itype (Designated_Type (Etype (Comp))) then
2006 Check_Itype (Etype (Comp));
2010 (Designated_Type (Etype (Comp)), Loc, Result);
2015 elsif Is_Access_Type (Etype (Comp))
2016 and then Is_Itype (Designated_Type (Etype (Comp)))
2018 Check_Itype (Etype (Comp));
2020 elsif Is_Array_Type (Etype (Comp))
2021 and then Is_Access_Type (Component_Type (Etype (Comp)))
2022 and then Present (Parent (Comp))
2023 and then Nkind (Parent (Comp)) = N_Component_Declaration
2024 and then Present (Expression (Parent (Comp)))
2025 and then Nkind (Expression (Parent (Comp))) = N_Aggregate
2026 and then Is_Fully_Defined
2027 (Designated_Type (Component_Type (Etype (Comp))))
2031 (Component_Type (Etype (Comp))), Loc, Result);
2038 -- Deal with pragma Bit_Order setting non-standard bit order
2040 if Reverse_Bit_Order (Rec) and then Base_Type (Rec) = Rec then
2041 if not Placed_Component then
2043 Get_Attribute_Definition_Clause (Rec, Attribute_Bit_Order);
2044 Error_Msg_N ("?Bit_Order specification has no effect", ADC);
2046 ("\?since no component clauses were specified", ADC);
2048 -- Here is where we do the processing for reversed bit order
2051 Adjust_Record_For_Reverse_Bit_Order (Rec);
2055 -- Complete error checking on record representation clause (e.g.
2056 -- overlap of components). This is called after adjusting the
2057 -- record for reverse bit order.
2060 RRC : constant Node_Id := Get_Record_Representation_Clause (Rec);
2062 if Present (RRC) then
2063 Check_Record_Representation_Clause (RRC);
2067 -- Set OK_To_Reorder_Components depending on debug flags
2069 if Rec = Base_Type (Rec)
2070 and then Convention (Rec) = Convention_Ada
2072 if (Has_Discriminants (Rec) and then Debug_Flag_Dot_V)
2074 (not Has_Discriminants (Rec) and then Debug_Flag_Dot_R)
2076 Set_OK_To_Reorder_Components (Rec);
2080 -- Check for useless pragma Pack when all components placed. We only
2081 -- do this check for record types, not subtypes, since a subtype may
2082 -- have all its components placed, and it still makes perfectly good
2083 -- sense to pack other subtypes or the parent type. We do not give
2084 -- this warning if Optimize_Alignment is set to Space, since the
2085 -- pragma Pack does have an effect in this case (it always resets
2086 -- the alignment to one).
2088 if Ekind (Rec) = E_Record_Type
2089 and then Is_Packed (Rec)
2090 and then not Unplaced_Component
2091 and then Optimize_Alignment /= 'S'
2093 -- Reset packed status. Probably not necessary, but we do it so
2094 -- that there is no chance of the back end doing something strange
2095 -- with this redundant indication of packing.
2097 Set_Is_Packed (Rec, False);
2099 -- Give warning if redundant constructs warnings on
2101 if Warn_On_Redundant_Constructs then
2102 Error_Msg_N -- CODEFIX
2103 ("?pragma Pack has no effect, no unplaced components",
2104 Get_Rep_Pragma (Rec, Name_Pack));
2108 -- If this is the record corresponding to a remote type, freeze the
2109 -- remote type here since that is what we are semantically freezing.
2110 -- This prevents the freeze node for that type in an inner scope.
2112 -- Also, Check for controlled components and unchecked unions.
2113 -- Finally, enforce the restriction that access attributes with a
2114 -- current instance prefix can only apply to limited types.
2116 if Ekind (Rec) = E_Record_Type then
2117 if Present (Corresponding_Remote_Type (Rec)) then
2119 (Corresponding_Remote_Type (Rec), Loc, Result);
2122 Comp := First_Component (Rec);
2123 while Present (Comp) loop
2125 -- Do not set Has_Controlled_Component on a class-wide
2126 -- equivalent type. See Make_CW_Equivalent_Type.
2128 if not Is_Class_Wide_Equivalent_Type (Rec)
2129 and then (Has_Controlled_Component (Etype (Comp))
2130 or else (Chars (Comp) /= Name_uParent
2131 and then Is_Controlled (Etype (Comp)))
2132 or else (Is_Protected_Type (Etype (Comp))
2134 (Corresponding_Record_Type
2136 and then Has_Controlled_Component
2137 (Corresponding_Record_Type
2140 Set_Has_Controlled_Component (Rec);
2144 if Has_Unchecked_Union (Etype (Comp)) then
2145 Set_Has_Unchecked_Union (Rec);
2148 if Has_Per_Object_Constraint (Comp) then
2150 -- Scan component declaration for likely misuses of current
2151 -- instance, either in a constraint or a default expression.
2153 Check_Current_Instance (Parent (Comp));
2156 Next_Component (Comp);
2160 Set_Component_Alignment_If_Not_Set (Rec);
2162 -- For first subtypes, check if there are any fixed-point fields with
2163 -- component clauses, where we must check the size. This is not done
2164 -- till the freeze point, since for fixed-point types, we do not know
2165 -- the size until the type is frozen. Similar processing applies to
2166 -- bit packed arrays.
2168 if Is_First_Subtype (Rec) then
2169 Comp := First_Component (Rec);
2171 while Present (Comp) loop
2172 if Present (Component_Clause (Comp))
2173 and then (Is_Fixed_Point_Type (Etype (Comp))
2175 Is_Bit_Packed_Array (Etype (Comp)))
2178 (Component_Name (Component_Clause (Comp)),
2184 Next_Component (Comp);
2188 -- Generate warning for applying C or C++ convention to a record
2189 -- with discriminants. This is suppressed for the unchecked union
2190 -- case, since the whole point in this case is interface C. We also
2191 -- do not generate this within instantiations, since we will have
2192 -- generated a message on the template.
2194 if Has_Discriminants (E)
2195 and then not Is_Unchecked_Union (E)
2196 and then (Convention (E) = Convention_C
2198 Convention (E) = Convention_CPP)
2199 and then Comes_From_Source (E)
2200 and then not In_Instance
2201 and then not Has_Warnings_Off (E)
2202 and then not Has_Warnings_Off (Base_Type (E))
2205 Cprag : constant Node_Id := Get_Rep_Pragma (E, Name_Convention);
2209 if Present (Cprag) then
2210 A2 := Next (First (Pragma_Argument_Associations (Cprag)));
2212 if Convention (E) = Convention_C then
2214 ("?variant record has no direct equivalent in C", A2);
2217 ("?variant record has no direct equivalent in C++", A2);
2221 ("\?use of convention for type& is dubious", A2, E);
2226 -- See if Size is too small as is (and implicit packing might help)
2228 if not Is_Packed (Rec)
2230 -- No implicit packing if even one component is explicitly placed
2232 and then not Placed_Component
2234 -- Must have size clause and all scalar components
2236 and then Has_Size_Clause (Rec)
2237 and then All_Scalar_Components
2239 -- Do not try implicit packing on records with discriminants, too
2240 -- complicated, especially in the variant record case.
2242 and then not Has_Discriminants (Rec)
2244 -- We can implicitly pack if the specified size of the record is
2245 -- less than the sum of the object sizes (no point in packing if
2246 -- this is not the case).
2248 and then Esize (Rec) < Scalar_Component_Total_Esize
2250 -- And the total RM size cannot be greater than the specified size
2251 -- since otherwise packing will not get us where we have to be!
2253 and then Esize (Rec) >= Scalar_Component_Total_RM_Size
2255 -- Never do implicit packing in CodePeer mode since we don't do
2256 -- any packing ever in this mode (why not???)
2258 and then not CodePeer_Mode
2260 -- If implicit packing enabled, do it
2262 if Implicit_Packing then
2263 Set_Is_Packed (Rec);
2265 -- Otherwise flag the size clause
2269 Sz : constant Node_Id := Size_Clause (Rec);
2271 Error_Msg_NE -- CODEFIX
2272 ("size given for& too small", Sz, Rec);
2273 Error_Msg_N -- CODEFIX
2274 ("\use explicit pragma Pack "
2275 & "or use pragma Implicit_Packing", Sz);
2279 end Freeze_Record_Type;
2281 -- Start of processing for Freeze_Entity
2284 -- We are going to test for various reasons why this entity need not be
2285 -- frozen here, but in the case of an Itype that's defined within a
2286 -- record, that test actually applies to the record.
2288 if Is_Itype (E) and then Is_Record_Type (Scope (E)) then
2289 Test_E := Scope (E);
2290 elsif Is_Itype (E) and then Present (Underlying_Type (Scope (E)))
2291 and then Is_Record_Type (Underlying_Type (Scope (E)))
2293 Test_E := Underlying_Type (Scope (E));
2296 -- Do not freeze if already frozen since we only need one freeze node
2298 if Is_Frozen (E) then
2301 -- It is improper to freeze an external entity within a generic because
2302 -- its freeze node will appear in a non-valid context. The entity will
2303 -- be frozen in the proper scope after the current generic is analyzed.
2305 elsif Inside_A_Generic and then External_Ref_In_Generic (Test_E) then
2308 -- Do not freeze a global entity within an inner scope created during
2309 -- expansion. A call to subprogram E within some internal procedure
2310 -- (a stream attribute for example) might require freezing E, but the
2311 -- freeze node must appear in the same declarative part as E itself.
2312 -- The two-pass elaboration mechanism in gigi guarantees that E will
2313 -- be frozen before the inner call is elaborated. We exclude constants
2314 -- from this test, because deferred constants may be frozen early, and
2315 -- must be diagnosed (e.g. in the case of a deferred constant being used
2316 -- in a default expression). If the enclosing subprogram comes from
2317 -- source, or is a generic instance, then the freeze point is the one
2318 -- mandated by the language, and we freeze the entity. A subprogram that
2319 -- is a child unit body that acts as a spec does not have a spec that
2320 -- comes from source, but can only come from source.
2322 elsif In_Open_Scopes (Scope (Test_E))
2323 and then Scope (Test_E) /= Current_Scope
2324 and then Ekind (Test_E) /= E_Constant
2327 S : Entity_Id := Current_Scope;
2331 while Present (S) loop
2332 if Is_Overloadable (S) then
2333 if Comes_From_Source (S)
2334 or else Is_Generic_Instance (S)
2335 or else Is_Child_Unit (S)
2347 -- Similarly, an inlined instance body may make reference to global
2348 -- entities, but these references cannot be the proper freezing point
2349 -- for them, and in the absence of inlining freezing will take place in
2350 -- their own scope. Normally instance bodies are analyzed after the
2351 -- enclosing compilation, and everything has been frozen at the proper
2352 -- place, but with front-end inlining an instance body is compiled
2353 -- before the end of the enclosing scope, and as a result out-of-order
2354 -- freezing must be prevented.
2356 elsif Front_End_Inlining
2357 and then In_Instance_Body
2358 and then Present (Scope (Test_E))
2361 S : Entity_Id := Scope (Test_E);
2364 while Present (S) loop
2365 if Is_Generic_Instance (S) then
2378 -- Here to freeze the entity
2383 -- Case of entity being frozen is other than a type
2385 if not Is_Type (E) then
2387 -- If entity is exported or imported and does not have an external
2388 -- name, now is the time to provide the appropriate default name.
2389 -- Skip this if the entity is stubbed, since we don't need a name
2390 -- for any stubbed routine. For the case on intrinsics, if no
2391 -- external name is specified, then calls will be handled in
2392 -- Exp_Intr.Expand_Intrinsic_Call, and no name is needed. If an
2393 -- external name is provided, then Expand_Intrinsic_Call leaves
2394 -- calls in place for expansion by GIGI.
2396 if (Is_Imported (E) or else Is_Exported (E))
2397 and then No (Interface_Name (E))
2398 and then Convention (E) /= Convention_Stubbed
2399 and then Convention (E) /= Convention_Intrinsic
2401 Set_Encoded_Interface_Name
2402 (E, Get_Default_External_Name (E));
2404 -- If entity is an atomic object appearing in a declaration and
2405 -- the expression is an aggregate, assign it to a temporary to
2406 -- ensure that the actual assignment is done atomically rather
2407 -- than component-wise (the assignment to the temp may be done
2408 -- component-wise, but that is harmless).
2411 and then Nkind (Parent (E)) = N_Object_Declaration
2412 and then Present (Expression (Parent (E)))
2413 and then Nkind (Expression (Parent (E))) = N_Aggregate
2415 Is_Atomic_Aggregate (Expression (Parent (E)), Etype (E))
2420 -- For a subprogram, freeze all parameter types and also the return
2421 -- type (RM 13.14(14)). However skip this for internal subprograms.
2422 -- This is also the point where any extra formal parameters are
2423 -- created since we now know whether the subprogram will use a
2424 -- foreign convention.
2426 if Is_Subprogram (E) then
2427 if not Is_Internal (E) then
2431 Warn_Node : Node_Id;
2434 -- Loop through formals
2436 Formal := First_Formal (E);
2437 while Present (Formal) loop
2438 F_Type := Etype (Formal);
2439 Freeze_And_Append (F_Type, Loc, Result);
2441 if Is_Private_Type (F_Type)
2442 and then Is_Private_Type (Base_Type (F_Type))
2443 and then No (Full_View (Base_Type (F_Type)))
2444 and then not Is_Generic_Type (F_Type)
2445 and then not Is_Derived_Type (F_Type)
2447 -- If the type of a formal is incomplete, subprogram
2448 -- is being frozen prematurely. Within an instance
2449 -- (but not within a wrapper package) this is an
2450 -- artifact of our need to regard the end of an
2451 -- instantiation as a freeze point. Otherwise it is
2452 -- a definite error.
2455 Set_Is_Frozen (E, False);
2458 elsif not After_Last_Declaration
2459 and then not Freezing_Library_Level_Tagged_Type
2461 Error_Msg_Node_1 := F_Type;
2463 ("type& must be fully defined before this point",
2468 -- Check suspicious parameter for C function. These tests
2469 -- apply only to exported/imported subprograms.
2471 if Warn_On_Export_Import
2472 and then Comes_From_Source (E)
2473 and then (Convention (E) = Convention_C
2475 Convention (E) = Convention_CPP)
2476 and then (Is_Imported (E) or else Is_Exported (E))
2477 and then Convention (E) /= Convention (Formal)
2478 and then not Has_Warnings_Off (E)
2479 and then not Has_Warnings_Off (F_Type)
2480 and then not Has_Warnings_Off (Formal)
2482 -- Qualify mention of formals with subprogram name
2484 Error_Msg_Qual_Level := 1;
2486 -- Check suspicious use of fat C pointer
2488 if Is_Access_Type (F_Type)
2489 and then Esize (F_Type) > Ttypes.System_Address_Size
2492 ("?type of & does not correspond to C pointer!",
2495 -- Check suspicious return of boolean
2497 elsif Root_Type (F_Type) = Standard_Boolean
2498 and then Convention (F_Type) = Convention_Ada
2499 and then not Has_Warnings_Off (F_Type)
2500 and then not Has_Size_Clause (F_Type)
2501 and then VM_Target = No_VM
2503 Error_Msg_N ("& is an 8-bit Ada Boolean?", Formal);
2505 ("\use appropriate corresponding type in C "
2506 & "(e.g. char)?", Formal);
2508 -- Check suspicious tagged type
2510 elsif (Is_Tagged_Type (F_Type)
2511 or else (Is_Access_Type (F_Type)
2514 (Designated_Type (F_Type))))
2515 and then Convention (E) = Convention_C
2518 ("?& involves a tagged type which does not "
2519 & "correspond to any C type!", Formal);
2521 -- Check wrong convention subprogram pointer
2523 elsif Ekind (F_Type) = E_Access_Subprogram_Type
2524 and then not Has_Foreign_Convention (F_Type)
2527 ("?subprogram pointer & should "
2528 & "have foreign convention!", Formal);
2529 Error_Msg_Sloc := Sloc (F_Type);
2531 ("\?add Convention pragma to declaration of &#",
2535 -- Turn off name qualification after message output
2537 Error_Msg_Qual_Level := 0;
2540 -- Check for unconstrained array in exported foreign
2543 if Has_Foreign_Convention (E)
2544 and then not Is_Imported (E)
2545 and then Is_Array_Type (F_Type)
2546 and then not Is_Constrained (F_Type)
2547 and then Warn_On_Export_Import
2549 -- Exclude VM case, since both .NET and JVM can handle
2550 -- unconstrained arrays without a problem.
2552 and then VM_Target = No_VM
2554 Error_Msg_Qual_Level := 1;
2556 -- If this is an inherited operation, place the
2557 -- warning on the derived type declaration, rather
2558 -- than on the original subprogram.
2560 if Nkind (Original_Node (Parent (E))) =
2561 N_Full_Type_Declaration
2563 Warn_Node := Parent (E);
2565 if Formal = First_Formal (E) then
2567 ("?in inherited operation&", Warn_Node, E);
2570 Warn_Node := Formal;
2574 ("?type of argument& is unconstrained array",
2577 ("?foreign caller must pass bounds explicitly",
2579 Error_Msg_Qual_Level := 0;
2582 if not From_With_Type (F_Type) then
2583 if Is_Access_Type (F_Type) then
2584 F_Type := Designated_Type (F_Type);
2587 -- If the formal is an anonymous_access_to_subprogram
2588 -- freeze the subprogram type as well, to prevent
2589 -- scope anomalies in gigi, because there is no other
2590 -- clear point at which it could be frozen.
2592 if Is_Itype (Etype (Formal))
2593 and then Ekind (F_Type) = E_Subprogram_Type
2595 Freeze_And_Append (F_Type, Loc, Result);
2599 Next_Formal (Formal);
2602 -- Case of function: similar checks on return type
2604 if Ekind (E) = E_Function then
2606 -- Freeze return type
2608 R_Type := Etype (E);
2609 Freeze_And_Append (R_Type, Loc, Result);
2611 -- Check suspicious return type for C function
2613 if Warn_On_Export_Import
2614 and then (Convention (E) = Convention_C
2616 Convention (E) = Convention_CPP)
2617 and then (Is_Imported (E) or else Is_Exported (E))
2619 -- Check suspicious return of fat C pointer
2621 if Is_Access_Type (R_Type)
2622 and then Esize (R_Type) > Ttypes.System_Address_Size
2623 and then not Has_Warnings_Off (E)
2624 and then not Has_Warnings_Off (R_Type)
2627 ("?return type of& does not "
2628 & "correspond to C pointer!", E);
2630 -- Check suspicious return of boolean
2632 elsif Root_Type (R_Type) = Standard_Boolean
2633 and then Convention (R_Type) = Convention_Ada
2634 and then VM_Target = No_VM
2635 and then not Has_Warnings_Off (E)
2636 and then not Has_Warnings_Off (R_Type)
2637 and then not Has_Size_Clause (R_Type)
2640 N : constant Node_Id :=
2641 Result_Definition (Declaration_Node (E));
2644 ("return type of & is an 8-bit Ada Boolean?",
2647 ("\use appropriate corresponding type in C "
2648 & "(e.g. char)?", N, E);
2651 -- Check suspicious return tagged type
2653 elsif (Is_Tagged_Type (R_Type)
2654 or else (Is_Access_Type (R_Type)
2657 (Designated_Type (R_Type))))
2658 and then Convention (E) = Convention_C
2659 and then not Has_Warnings_Off (E)
2660 and then not Has_Warnings_Off (R_Type)
2663 ("?return type of & does not "
2664 & "correspond to C type!", E);
2666 -- Check return of wrong convention subprogram pointer
2668 elsif Ekind (R_Type) = E_Access_Subprogram_Type
2669 and then not Has_Foreign_Convention (R_Type)
2670 and then not Has_Warnings_Off (E)
2671 and then not Has_Warnings_Off (R_Type)
2674 ("?& should return a foreign "
2675 & "convention subprogram pointer", E);
2676 Error_Msg_Sloc := Sloc (R_Type);
2678 ("\?add Convention pragma to declaration of& #",
2683 -- Give warning for suspicous return of a result of an
2684 -- unconstrained array type in a foreign convention
2687 if Has_Foreign_Convention (E)
2689 -- We are looking for a return of unconstrained array
2691 and then Is_Array_Type (R_Type)
2692 and then not Is_Constrained (R_Type)
2694 -- Exclude imported routines, the warning does not
2695 -- belong on the import, but on the routine definition.
2697 and then not Is_Imported (E)
2699 -- Exclude VM case, since both .NET and JVM can handle
2700 -- return of unconstrained arrays without a problem.
2702 and then VM_Target = No_VM
2704 -- Check that general warning is enabled, and that it
2705 -- is not suppressed for this particular case.
2707 and then Warn_On_Export_Import
2708 and then not Has_Warnings_Off (E)
2709 and then not Has_Warnings_Off (R_Type)
2712 ("?foreign convention function& should not " &
2713 "return unconstrained array!", E);
2719 -- Must freeze its parent first if it is a derived subprogram
2721 if Present (Alias (E)) then
2722 Freeze_And_Append (Alias (E), Loc, Result);
2725 -- We don't freeze internal subprograms, because we don't normally
2726 -- want addition of extra formals or mechanism setting to happen
2727 -- for those. However we do pass through predefined dispatching
2728 -- cases, since extra formals may be needed in some cases, such as
2729 -- for the stream 'Input function (build-in-place formals).
2731 if not Is_Internal (E)
2732 or else Is_Predefined_Dispatching_Operation (E)
2734 Freeze_Subprogram (E);
2737 -- Here for other than a subprogram or type
2740 -- If entity has a type, and it is not a generic unit, then
2741 -- freeze it first (RM 13.14(10)).
2743 if Present (Etype (E))
2744 and then Ekind (E) /= E_Generic_Function
2746 Freeze_And_Append (Etype (E), Loc, Result);
2749 -- Special processing for objects created by object declaration
2751 if Nkind (Declaration_Node (E)) = N_Object_Declaration then
2753 -- Abstract type allowed only for C++ imported variables or
2756 -- Note: we inhibit this check for objects that do not come
2757 -- from source because there is at least one case (the
2758 -- expansion of x'class'input where x is abstract) where we
2759 -- legitimately generate an abstract object.
2761 if Is_Abstract_Type (Etype (E))
2762 and then Comes_From_Source (Parent (E))
2763 and then not (Is_Imported (E)
2764 and then Is_CPP_Class (Etype (E)))
2766 Error_Msg_N ("type of object cannot be abstract",
2767 Object_Definition (Parent (E)));
2769 if Is_CPP_Class (Etype (E)) then
2771 ("\} may need a cpp_constructor",
2772 Object_Definition (Parent (E)), Etype (E));
2776 -- For object created by object declaration, perform required
2777 -- categorization (preelaborate and pure) checks. Defer these
2778 -- checks to freeze time since pragma Import inhibits default
2779 -- initialization and thus pragma Import affects these checks.
2781 Validate_Object_Declaration (Declaration_Node (E));
2783 -- If there is an address clause, check that it is valid
2785 Check_Address_Clause (E);
2787 -- If the object needs any kind of default initialization, an
2788 -- error must be issued if No_Default_Initialization applies.
2789 -- The check doesn't apply to imported objects, which are not
2790 -- ever default initialized, and is why the check is deferred
2791 -- until freezing, at which point we know if Import applies.
2792 -- Deferred constants are also exempted from this test because
2793 -- their completion is explicit, or through an import pragma.
2795 if Ekind (E) = E_Constant
2796 and then Present (Full_View (E))
2800 elsif Comes_From_Source (E)
2801 and then not Is_Imported (E)
2802 and then not Has_Init_Expression (Declaration_Node (E))
2804 ((Has_Non_Null_Base_Init_Proc (Etype (E))
2805 and then not No_Initialization (Declaration_Node (E))
2806 and then not Is_Value_Type (Etype (E))
2807 and then not Suppress_Init_Proc (Etype (E)))
2809 (Needs_Simple_Initialization (Etype (E))
2810 and then not Is_Internal (E)))
2812 Has_Default_Initialization := True;
2814 (No_Default_Initialization, Declaration_Node (E));
2817 -- Check that a Thread_Local_Storage variable does not have
2818 -- default initialization, and any explicit initialization must
2819 -- either be the null constant or a static constant.
2821 if Has_Pragma_Thread_Local_Storage (E) then
2823 Decl : constant Node_Id := Declaration_Node (E);
2825 if Has_Default_Initialization
2827 (Has_Init_Expression (Decl)
2829 (No (Expression (Decl))
2831 (Is_Static_Expression (Expression (Decl))
2833 Nkind (Expression (Decl)) = N_Null)))
2836 ("Thread_Local_Storage variable& is "
2837 & "improperly initialized", Decl, E);
2839 ("\only allowed initialization is explicit "
2840 & "NULL or static expression", Decl, E);
2845 -- For imported objects, set Is_Public unless there is also an
2846 -- address clause, which means that there is no external symbol
2847 -- needed for the Import (Is_Public may still be set for other
2848 -- unrelated reasons). Note that we delayed this processing
2849 -- till freeze time so that we can be sure not to set the flag
2850 -- if there is an address clause. If there is such a clause,
2851 -- then the only purpose of the Import pragma is to suppress
2852 -- implicit initialization.
2855 and then No (Address_Clause (E))
2860 -- For convention C objects of an enumeration type, warn if
2861 -- the size is not integer size and no explicit size given.
2862 -- Skip warning for Boolean, and Character, assume programmer
2863 -- expects 8-bit sizes for these cases.
2865 if (Convention (E) = Convention_C
2867 Convention (E) = Convention_CPP)
2868 and then Is_Enumeration_Type (Etype (E))
2869 and then not Is_Character_Type (Etype (E))
2870 and then not Is_Boolean_Type (Etype (E))
2871 and then Esize (Etype (E)) < Standard_Integer_Size
2872 and then not Has_Size_Clause (E)
2874 Error_Msg_Uint_1 := UI_From_Int (Standard_Integer_Size);
2876 ("?convention C enumeration object has size less than ^",
2878 Error_Msg_N ("\?use explicit size clause to set size", E);
2882 -- Check that a constant which has a pragma Volatile[_Components]
2883 -- or Atomic[_Components] also has a pragma Import (RM C.6(13)).
2885 -- Note: Atomic[_Components] also sets Volatile[_Components]
2887 if Ekind (E) = E_Constant
2888 and then (Has_Volatile_Components (E) or else Is_Volatile (E))
2889 and then not Is_Imported (E)
2891 -- Make sure we actually have a pragma, and have not merely
2892 -- inherited the indication from elsewhere (e.g. an address
2893 -- clause, which is not good enough in RM terms!)
2895 if Has_Rep_Pragma (E, Name_Atomic)
2897 Has_Rep_Pragma (E, Name_Atomic_Components)
2900 ("stand alone atomic constant must be " &
2901 "imported (RM C.6(13))", E);
2903 elsif Has_Rep_Pragma (E, Name_Volatile)
2905 Has_Rep_Pragma (E, Name_Volatile_Components)
2908 ("stand alone volatile constant must be " &
2909 "imported (RM C.6(13))", E);
2913 -- Static objects require special handling
2915 if (Ekind (E) = E_Constant or else Ekind (E) = E_Variable)
2916 and then Is_Statically_Allocated (E)
2918 Freeze_Static_Object (E);
2921 -- Remaining step is to layout objects
2923 if Ekind (E) = E_Variable
2925 Ekind (E) = E_Constant
2927 Ekind (E) = E_Loop_Parameter
2935 -- Case of a type or subtype being frozen
2938 -- We used to check here that a full type must have preelaborable
2939 -- initialization if it completes a private type specified with
2940 -- pragma Preelaborable_Intialization, but that missed cases where
2941 -- the types occur within a generic package, since the freezing
2942 -- that occurs within a containing scope generally skips traversal
2943 -- of a generic unit's declarations (those will be frozen within
2944 -- instances). This check was moved to Analyze_Package_Specification.
2946 -- The type may be defined in a generic unit. This can occur when
2947 -- freezing a generic function that returns the type (which is
2948 -- defined in a parent unit). It is clearly meaningless to freeze
2949 -- this type. However, if it is a subtype, its size may be determi-
2950 -- nable and used in subsequent checks, so might as well try to
2953 if Present (Scope (E))
2954 and then Is_Generic_Unit (Scope (E))
2956 Check_Compile_Time_Size (E);
2960 -- Deal with special cases of freezing for subtype
2962 if E /= Base_Type (E) then
2964 -- Before we do anything else, a specialized test for the case of
2965 -- a size given for an array where the array needs to be packed,
2966 -- but was not so the size cannot be honored. This would of course
2967 -- be caught by the backend, and indeed we don't catch all cases.
2968 -- The point is that we can give a better error message in those
2969 -- cases that we do catch with the circuitry here. Also if pragma
2970 -- Implicit_Packing is set, this is where the packing occurs.
2972 -- The reason we do this so early is that the processing in the
2973 -- automatic packing case affects the layout of the base type, so
2974 -- it must be done before we freeze the base type.
2976 if Is_Array_Type (E) then
2979 Ctyp : constant Entity_Id := Component_Type (E);
2982 -- Check enabling conditions. These are straightforward
2983 -- except for the test for a limited composite type. This
2984 -- eliminates the rare case of a array of limited components
2985 -- where there are issues of whether or not we can go ahead
2986 -- and pack the array (since we can't freely pack and unpack
2987 -- arrays if they are limited).
2989 -- Note that we check the root type explicitly because the
2990 -- whole point is we are doing this test before we have had
2991 -- a chance to freeze the base type (and it is that freeze
2992 -- action that causes stuff to be inherited).
2994 if Present (Size_Clause (E))
2995 and then Known_Static_Esize (E)
2996 and then not Is_Packed (E)
2997 and then not Has_Pragma_Pack (E)
2998 and then Number_Dimensions (E) = 1
2999 and then not Has_Component_Size_Clause (E)
3000 and then Known_Static_Esize (Ctyp)
3001 and then not Is_Limited_Composite (E)
3002 and then not Is_Packed (Root_Type (E))
3003 and then not Has_Component_Size_Clause (Root_Type (E))
3004 and then not CodePeer_Mode
3006 Get_Index_Bounds (First_Index (E), Lo, Hi);
3008 if Compile_Time_Known_Value (Lo)
3009 and then Compile_Time_Known_Value (Hi)
3010 and then Known_Static_RM_Size (Ctyp)
3011 and then RM_Size (Ctyp) < 64
3014 Lov : constant Uint := Expr_Value (Lo);
3015 Hiv : constant Uint := Expr_Value (Hi);
3016 Len : constant Uint := UI_Max
3019 Rsiz : constant Uint := RM_Size (Ctyp);
3020 SZ : constant Node_Id := Size_Clause (E);
3021 Btyp : constant Entity_Id := Base_Type (E);
3023 -- What we are looking for here is the situation where
3024 -- the RM_Size given would be exactly right if there
3025 -- was a pragma Pack (resulting in the component size
3026 -- being the same as the RM_Size). Furthermore, the
3027 -- component type size must be an odd size (not a
3028 -- multiple of storage unit). If the component RM size
3029 -- is an exact number of storage units that is a power
3030 -- of two, the array is not packed and has a standard
3034 if RM_Size (E) = Len * Rsiz
3035 and then Rsiz mod System_Storage_Unit /= 0
3037 -- For implicit packing mode, just set the
3038 -- component size silently.
3040 if Implicit_Packing then
3041 Set_Component_Size (Btyp, Rsiz);
3042 Set_Is_Bit_Packed_Array (Btyp);
3043 Set_Is_Packed (Btyp);
3044 Set_Has_Non_Standard_Rep (Btyp);
3046 -- Otherwise give an error message
3050 ("size given for& too small", SZ, E);
3051 Error_Msg_N -- CODEFIX
3052 ("\use explicit pragma Pack "
3053 & "or use pragma Implicit_Packing", SZ);
3056 elsif RM_Size (E) = Len * Rsiz
3057 and then Implicit_Packing
3059 (Rsiz / System_Storage_Unit = 1
3060 or else Rsiz / System_Storage_Unit = 2
3061 or else Rsiz / System_Storage_Unit = 4)
3064 -- Not a packed array, but indicate the desired
3065 -- component size, for the back-end.
3067 Set_Component_Size (Btyp, Rsiz);
3075 -- If ancestor subtype present, freeze that first. Note that this
3076 -- will also get the base type frozen.
3078 Atype := Ancestor_Subtype (E);
3080 if Present (Atype) then
3081 Freeze_And_Append (Atype, Loc, Result);
3083 -- Otherwise freeze the base type of the entity before freezing
3084 -- the entity itself (RM 13.14(15)).
3086 elsif E /= Base_Type (E) then
3087 Freeze_And_Append (Base_Type (E), Loc, Result);
3090 -- For a derived type, freeze its parent type first (RM 13.14(15))
3092 elsif Is_Derived_Type (E) then
3093 Freeze_And_Append (Etype (E), Loc, Result);
3094 Freeze_And_Append (First_Subtype (Etype (E)), Loc, Result);
3097 -- For array type, freeze index types and component type first
3098 -- before freezing the array (RM 13.14(15)).
3100 if Is_Array_Type (E) then
3102 Ctyp : constant Entity_Id := Component_Type (E);
3104 Non_Standard_Enum : Boolean := False;
3105 -- Set true if any of the index types is an enumeration type
3106 -- with a non-standard representation.
3109 Freeze_And_Append (Ctyp, Loc, Result);
3111 Indx := First_Index (E);
3112 while Present (Indx) loop
3113 Freeze_And_Append (Etype (Indx), Loc, Result);
3115 if Is_Enumeration_Type (Etype (Indx))
3116 and then Has_Non_Standard_Rep (Etype (Indx))
3118 Non_Standard_Enum := True;
3124 -- Processing that is done only for base types
3126 if Ekind (E) = E_Array_Type then
3128 -- Propagate flags for component type
3130 if Is_Controlled (Component_Type (E))
3131 or else Has_Controlled_Component (Ctyp)
3133 Set_Has_Controlled_Component (E);
3136 if Has_Unchecked_Union (Component_Type (E)) then
3137 Set_Has_Unchecked_Union (E);
3140 -- If packing was requested or if the component size was set
3141 -- explicitly, then see if bit packing is required. This
3142 -- processing is only done for base types, since all the
3143 -- representation aspects involved are type-related. This
3144 -- is not just an optimization, if we start processing the
3145 -- subtypes, they interfere with the settings on the base
3146 -- type (this is because Is_Packed has a slightly different
3147 -- meaning before and after freezing).
3154 if (Is_Packed (E) or else Has_Pragma_Pack (E))
3155 and then not Has_Atomic_Components (E)
3156 and then Known_Static_RM_Size (Ctyp)
3158 Csiz := UI_Max (RM_Size (Ctyp), 1);
3160 elsif Known_Component_Size (E) then
3161 Csiz := Component_Size (E);
3163 elsif not Known_Static_Esize (Ctyp) then
3167 Esiz := Esize (Ctyp);
3169 -- We can set the component size if it is less than
3170 -- 16, rounding it up to the next storage unit size.
3174 elsif Esiz <= 16 then
3180 -- Set component size up to match alignment if it
3181 -- would otherwise be less than the alignment. This
3182 -- deals with cases of types whose alignment exceeds
3183 -- their size (padded types).
3187 A : constant Uint := Alignment_In_Bits (Ctyp);
3196 -- Case of component size that may result in packing
3198 if 1 <= Csiz and then Csiz <= 64 then
3200 Ent : constant Entity_Id :=
3202 Pack_Pragma : constant Node_Id :=
3203 Get_Rep_Pragma (Ent, Name_Pack);
3204 Comp_Size_C : constant Node_Id :=
3205 Get_Attribute_Definition_Clause
3206 (Ent, Attribute_Component_Size);
3208 -- Warn if we have pack and component size so that
3209 -- the pack is ignored.
3211 -- Note: here we must check for the presence of a
3212 -- component size before checking for a Pack pragma
3213 -- to deal with the case where the array type is a
3214 -- derived type whose parent is currently private.
3216 if Present (Comp_Size_C)
3217 and then Has_Pragma_Pack (Ent)
3219 Error_Msg_Sloc := Sloc (Comp_Size_C);
3221 ("?pragma Pack for& ignored!",
3224 ("\?explicit component size given#!",
3228 -- Set component size if not already set by a
3229 -- component size clause.
3231 if not Present (Comp_Size_C) then
3232 Set_Component_Size (E, Csiz);
3235 -- Check for base type of 8, 16, 32 bits, where an
3236 -- unsigned subtype has a length one less than the
3237 -- base type (e.g. Natural subtype of Integer).
3239 -- In such cases, if a component size was not set
3240 -- explicitly, then generate a warning.
3242 if Has_Pragma_Pack (E)
3243 and then not Present (Comp_Size_C)
3245 (Csiz = 7 or else Csiz = 15 or else Csiz = 31)
3246 and then Esize (Base_Type (Ctyp)) = Csiz + 1
3248 Error_Msg_Uint_1 := Csiz;
3250 if Present (Pack_Pragma) then
3252 ("?pragma Pack causes component size "
3253 & "to be ^!", Pack_Pragma);
3255 ("\?use Component_Size to set "
3256 & "desired value!", Pack_Pragma);
3260 -- Actual packing is not needed for 8, 16, 32, 64.
3261 -- Also not needed for 24 if alignment is 1.
3267 or else (Csiz = 24 and then Alignment (Ctyp) = 1)
3269 -- Here the array was requested to be packed,
3270 -- but the packing request had no effect, so
3271 -- Is_Packed is reset.
3273 -- Note: semantically this means that we lose
3274 -- track of the fact that a derived type
3275 -- inherited a pragma Pack that was non-
3276 -- effective, but that seems fine.
3278 -- We regard a Pack pragma as a request to set
3279 -- a representation characteristic, and this
3280 -- request may be ignored.
3282 Set_Is_Packed (Base_Type (E), False);
3284 -- In all other cases, packing is indeed needed
3287 Set_Has_Non_Standard_Rep (Base_Type (E));
3288 Set_Is_Bit_Packed_Array (Base_Type (E));
3289 Set_Is_Packed (Base_Type (E));
3295 -- Processing that is done only for subtypes
3298 -- Acquire alignment from base type
3300 if Unknown_Alignment (E) then
3301 Set_Alignment (E, Alignment (Base_Type (E)));
3302 Adjust_Esize_Alignment (E);
3306 -- For bit-packed arrays, check the size
3308 if Is_Bit_Packed_Array (E) and then Known_RM_Size (E) then
3310 SizC : constant Node_Id := Size_Clause (E);
3313 pragma Warnings (Off, Discard);
3316 -- It is not clear if it is possible to have no size
3317 -- clause at this stage, but it is not worth worrying
3318 -- about. Post error on the entity name in the size
3319 -- clause if present, else on the type entity itself.
3321 if Present (SizC) then
3322 Check_Size (Name (SizC), E, RM_Size (E), Discard);
3324 Check_Size (E, E, RM_Size (E), Discard);
3329 -- If any of the index types was an enumeration type with
3330 -- a non-standard rep clause, then we indicate that the
3331 -- array type is always packed (even if it is not bit packed).
3333 if Non_Standard_Enum then
3334 Set_Has_Non_Standard_Rep (Base_Type (E));
3335 Set_Is_Packed (Base_Type (E));
3338 Set_Component_Alignment_If_Not_Set (E);
3340 -- If the array is packed, we must create the packed array
3341 -- type to be used to actually implement the type. This is
3342 -- only needed for real array types (not for string literal
3343 -- types, since they are present only for the front end).
3346 and then Ekind (E) /= E_String_Literal_Subtype
3348 Create_Packed_Array_Type (E);
3349 Freeze_And_Append (Packed_Array_Type (E), Loc, Result);
3351 -- Size information of packed array type is copied to the
3352 -- array type, since this is really the representation. But
3353 -- do not override explicit existing size values. If the
3354 -- ancestor subtype is constrained the packed_array_type
3355 -- will be inherited from it, but the size may have been
3356 -- provided already, and must not be overridden either.
3358 if not Has_Size_Clause (E)
3360 (No (Ancestor_Subtype (E))
3361 or else not Has_Size_Clause (Ancestor_Subtype (E)))
3363 Set_Esize (E, Esize (Packed_Array_Type (E)));
3364 Set_RM_Size (E, RM_Size (Packed_Array_Type (E)));
3367 if not Has_Alignment_Clause (E) then
3368 Set_Alignment (E, Alignment (Packed_Array_Type (E)));
3372 -- For non-packed arrays set the alignment of the array to the
3373 -- alignment of the component type if it is unknown. Skip this
3374 -- in atomic case (atomic arrays may need larger alignments).
3376 if not Is_Packed (E)
3377 and then Unknown_Alignment (E)
3378 and then Known_Alignment (Ctyp)
3379 and then Known_Static_Component_Size (E)
3380 and then Known_Static_Esize (Ctyp)
3381 and then Esize (Ctyp) = Component_Size (E)
3382 and then not Is_Atomic (E)
3384 Set_Alignment (E, Alignment (Component_Type (E)));
3388 -- For a class-wide type, the corresponding specific type is
3389 -- frozen as well (RM 13.14(15))
3391 elsif Is_Class_Wide_Type (E) then
3392 Freeze_And_Append (Root_Type (E), Loc, Result);
3394 -- If the base type of the class-wide type is still incomplete,
3395 -- the class-wide remains unfrozen as well. This is legal when
3396 -- E is the formal of a primitive operation of some other type
3397 -- which is being frozen.
3399 if not Is_Frozen (Root_Type (E)) then
3400 Set_Is_Frozen (E, False);
3404 -- If the Class_Wide_Type is an Itype (when type is the anonymous
3405 -- parent of a derived type) and it is a library-level entity,
3406 -- generate an itype reference for it. Otherwise, its first
3407 -- explicit reference may be in an inner scope, which will be
3408 -- rejected by the back-end.
3411 and then Is_Compilation_Unit (Scope (E))
3414 Ref : constant Node_Id := Make_Itype_Reference (Loc);
3419 Result := New_List (Ref);
3421 Append (Ref, Result);
3426 -- The equivalent type associated with a class-wide subtype needs
3427 -- to be frozen to ensure that its layout is done.
3429 if Ekind (E) = E_Class_Wide_Subtype
3430 and then Present (Equivalent_Type (E))
3432 Freeze_And_Append (Equivalent_Type (E), Loc, Result);
3435 -- For a record (sub)type, freeze all the component types (RM
3436 -- 13.14(15). We test for E_Record_(sub)Type here, rather than using
3437 -- Is_Record_Type, because we don't want to attempt the freeze for
3438 -- the case of a private type with record extension (we will do that
3439 -- later when the full type is frozen).
3441 elsif Ekind (E) = E_Record_Type
3442 or else Ekind (E) = E_Record_Subtype
3444 Freeze_Record_Type (E);
3446 -- For a concurrent type, freeze corresponding record type. This
3447 -- does not correspond to any specific rule in the RM, but the
3448 -- record type is essentially part of the concurrent type.
3449 -- Freeze as well all local entities. This includes record types
3450 -- created for entry parameter blocks, and whatever local entities
3451 -- may appear in the private part.
3453 elsif Is_Concurrent_Type (E) then
3454 if Present (Corresponding_Record_Type (E)) then
3456 (Corresponding_Record_Type (E), Loc, Result);
3459 Comp := First_Entity (E);
3460 while Present (Comp) loop
3461 if Is_Type (Comp) then
3462 Freeze_And_Append (Comp, Loc, Result);
3464 elsif (Ekind (Comp)) /= E_Function then
3465 if Is_Itype (Etype (Comp))
3466 and then Underlying_Type (Scope (Etype (Comp))) = E
3468 Undelay_Type (Etype (Comp));
3471 Freeze_And_Append (Etype (Comp), Loc, Result);
3477 -- Private types are required to point to the same freeze node as
3478 -- their corresponding full views. The freeze node itself has to
3479 -- point to the partial view of the entity (because from the partial
3480 -- view, we can retrieve the full view, but not the reverse).
3481 -- However, in order to freeze correctly, we need to freeze the full
3482 -- view. If we are freezing at the end of a scope (or within the
3483 -- scope of the private type), the partial and full views will have
3484 -- been swapped, the full view appears first in the entity chain and
3485 -- the swapping mechanism ensures that the pointers are properly set
3488 -- If we encounter the partial view before the full view (e.g. when
3489 -- freezing from another scope), we freeze the full view, and then
3490 -- set the pointers appropriately since we cannot rely on swapping to
3491 -- fix things up (subtypes in an outer scope might not get swapped).
3493 elsif Is_Incomplete_Or_Private_Type (E)
3494 and then not Is_Generic_Type (E)
3496 -- The construction of the dispatch table associated with library
3497 -- level tagged types forces freezing of all the primitives of the
3498 -- type, which may cause premature freezing of the partial view.
3502 -- type T is tagged private;
3503 -- type DT is new T with private;
3504 -- procedure Prim (X : in out T; Y : in out DT'class);
3506 -- type T is tagged null record;
3508 -- type DT is new T with null record;
3511 -- In this case the type will be frozen later by the usual
3512 -- mechanism: an object declaration, an instantiation, or the
3513 -- end of a declarative part.
3515 if Is_Library_Level_Tagged_Type (E)
3516 and then not Present (Full_View (E))
3518 Set_Is_Frozen (E, False);
3521 -- Case of full view present
3523 elsif Present (Full_View (E)) then
3525 -- If full view has already been frozen, then no further
3526 -- processing is required
3528 if Is_Frozen (Full_View (E)) then
3530 Set_Has_Delayed_Freeze (E, False);
3531 Set_Freeze_Node (E, Empty);
3532 Check_Debug_Info_Needed (E);
3534 -- Otherwise freeze full view and patch the pointers so that
3535 -- the freeze node will elaborate both views in the back-end.
3539 Full : constant Entity_Id := Full_View (E);
3542 if Is_Private_Type (Full)
3543 and then Present (Underlying_Full_View (Full))
3546 (Underlying_Full_View (Full), Loc, Result);
3549 Freeze_And_Append (Full, Loc, Result);
3551 if Has_Delayed_Freeze (E) then
3552 F_Node := Freeze_Node (Full);
3554 if Present (F_Node) then
3555 Set_Freeze_Node (E, F_Node);
3556 Set_Entity (F_Node, E);
3559 -- {Incomplete,Private}_Subtypes with Full_Views
3560 -- constrained by discriminants.
3562 Set_Has_Delayed_Freeze (E, False);
3563 Set_Freeze_Node (E, Empty);
3568 Check_Debug_Info_Needed (E);
3571 -- AI-117 requires that the convention of a partial view be the
3572 -- same as the convention of the full view. Note that this is a
3573 -- recognized breach of privacy, but it's essential for logical
3574 -- consistency of representation, and the lack of a rule in
3575 -- RM95 was an oversight.
3577 Set_Convention (E, Convention (Full_View (E)));
3579 Set_Size_Known_At_Compile_Time (E,
3580 Size_Known_At_Compile_Time (Full_View (E)));
3582 -- Size information is copied from the full view to the
3583 -- incomplete or private view for consistency.
3585 -- We skip this is the full view is not a type. This is very
3586 -- strange of course, and can only happen as a result of
3587 -- certain illegalities, such as a premature attempt to derive
3588 -- from an incomplete type.
3590 if Is_Type (Full_View (E)) then
3591 Set_Size_Info (E, Full_View (E));
3592 Set_RM_Size (E, RM_Size (Full_View (E)));
3597 -- Case of no full view present. If entity is derived or subtype,
3598 -- it is safe to freeze, correctness depends on the frozen status
3599 -- of parent. Otherwise it is either premature usage, or a Taft
3600 -- amendment type, so diagnosis is at the point of use and the
3601 -- type might be frozen later.
3603 elsif E /= Base_Type (E)
3604 or else Is_Derived_Type (E)
3609 Set_Is_Frozen (E, False);
3613 -- For access subprogram, freeze types of all formals, the return
3614 -- type was already frozen, since it is the Etype of the function.
3615 -- Formal types can be tagged Taft amendment types, but otherwise
3616 -- they cannot be incomplete.
3618 elsif Ekind (E) = E_Subprogram_Type then
3619 Formal := First_Formal (E);
3621 while Present (Formal) loop
3622 if Ekind (Etype (Formal)) = E_Incomplete_Type
3623 and then No (Full_View (Etype (Formal)))
3624 and then not Is_Value_Type (Etype (Formal))
3626 if Is_Tagged_Type (Etype (Formal)) then
3630 ("invalid use of incomplete type&", E, Etype (Formal));
3634 Freeze_And_Append (Etype (Formal), Loc, Result);
3635 Next_Formal (Formal);
3638 Freeze_Subprogram (E);
3640 -- For access to a protected subprogram, freeze the equivalent type
3641 -- (however this is not set if we are not generating code or if this
3642 -- is an anonymous type used just for resolution).
3644 elsif Is_Access_Protected_Subprogram_Type (E) then
3645 if Present (Equivalent_Type (E)) then
3646 Freeze_And_Append (Equivalent_Type (E), Loc, Result);
3650 -- Generic types are never seen by the back-end, and are also not
3651 -- processed by the expander (since the expander is turned off for
3652 -- generic processing), so we never need freeze nodes for them.
3654 if Is_Generic_Type (E) then
3658 -- Some special processing for non-generic types to complete
3659 -- representation details not known till the freeze point.
3661 if Is_Fixed_Point_Type (E) then
3662 Freeze_Fixed_Point_Type (E);
3664 -- Some error checks required for ordinary fixed-point type. Defer
3665 -- these till the freeze-point since we need the small and range
3666 -- values. We only do these checks for base types
3668 if Is_Ordinary_Fixed_Point_Type (E)
3669 and then E = Base_Type (E)
3671 if Small_Value (E) < Ureal_2_M_80 then
3672 Error_Msg_Name_1 := Name_Small;
3674 ("`&''%` too small, minimum allowed is 2.0'*'*(-80)", E);
3676 elsif Small_Value (E) > Ureal_2_80 then
3677 Error_Msg_Name_1 := Name_Small;
3679 ("`&''%` too large, maximum allowed is 2.0'*'*80", E);
3682 if Expr_Value_R (Type_Low_Bound (E)) < Ureal_M_10_36 then
3683 Error_Msg_Name_1 := Name_First;
3685 ("`&''%` too small, minimum allowed is -10.0'*'*36", E);
3688 if Expr_Value_R (Type_High_Bound (E)) > Ureal_10_36 then
3689 Error_Msg_Name_1 := Name_Last;
3691 ("`&''%` too large, maximum allowed is 10.0'*'*36", E);
3695 elsif Is_Enumeration_Type (E) then
3696 Freeze_Enumeration_Type (E);
3698 elsif Is_Integer_Type (E) then
3699 Adjust_Esize_For_Alignment (E);
3701 if Is_Modular_Integer_Type (E)
3702 and then Warn_On_Suspicious_Modulus_Value
3704 Check_Suspicious_Modulus (E);
3707 elsif Is_Access_Type (E) then
3709 -- Check restriction for standard storage pool
3711 if No (Associated_Storage_Pool (E)) then
3712 Check_Restriction (No_Standard_Storage_Pools, E);
3715 -- Deal with error message for pure access type. This is not an
3716 -- error in Ada 2005 if there is no pool (see AI-366).
3718 if Is_Pure_Unit_Access_Type (E)
3719 and then (Ada_Version < Ada_05
3720 or else not No_Pool_Assigned (E))
3722 Error_Msg_N ("named access type not allowed in pure unit", E);
3724 if Ada_Version >= Ada_05 then
3726 ("\would be legal if Storage_Size of 0 given?", E);
3728 elsif No_Pool_Assigned (E) then
3730 ("\would be legal in Ada 2005?", E);
3734 ("\would be legal in Ada 2005 if "
3735 & "Storage_Size of 0 given?", E);
3740 -- Case of composite types
3742 if Is_Composite_Type (E) then
3744 -- AI-117 requires that all new primitives of a tagged type must
3745 -- inherit the convention of the full view of the type. Inherited
3746 -- and overriding operations are defined to inherit the convention
3747 -- of their parent or overridden subprogram (also specified in
3748 -- AI-117), which will have occurred earlier (in Derive_Subprogram
3749 -- and New_Overloaded_Entity). Here we set the convention of
3750 -- primitives that are still convention Ada, which will ensure
3751 -- that any new primitives inherit the type's convention. Class-
3752 -- wide types can have a foreign convention inherited from their
3753 -- specific type, but are excluded from this since they don't have
3754 -- any associated primitives.
3756 if Is_Tagged_Type (E)
3757 and then not Is_Class_Wide_Type (E)
3758 and then Convention (E) /= Convention_Ada
3761 Prim_List : constant Elist_Id := Primitive_Operations (E);
3764 Prim := First_Elmt (Prim_List);
3765 while Present (Prim) loop
3766 if Convention (Node (Prim)) = Convention_Ada then
3767 Set_Convention (Node (Prim), Convention (E));
3776 -- Now that all types from which E may depend are frozen, see if the
3777 -- size is known at compile time, if it must be unsigned, or if
3778 -- strict alignment is required
3780 Check_Compile_Time_Size (E);
3781 Check_Unsigned_Type (E);
3783 if Base_Type (E) = E then
3784 Check_Strict_Alignment (E);
3787 -- Do not allow a size clause for a type which does not have a size
3788 -- that is known at compile time
3790 if Has_Size_Clause (E)
3791 and then not Size_Known_At_Compile_Time (E)
3793 -- Suppress this message if errors posted on E, even if we are
3794 -- in all errors mode, since this is often a junk message
3796 if not Error_Posted (E) then
3798 ("size clause not allowed for variable length type",
3803 -- Remaining process is to set/verify the representation information,
3804 -- in particular the size and alignment values. This processing is
3805 -- not required for generic types, since generic types do not play
3806 -- any part in code generation, and so the size and alignment values
3807 -- for such types are irrelevant.
3809 if Is_Generic_Type (E) then
3812 -- Otherwise we call the layout procedure
3818 -- End of freeze processing for type entities
3821 -- Here is where we logically freeze the current entity. If it has a
3822 -- freeze node, then this is the point at which the freeze node is
3823 -- linked into the result list.
3825 if Has_Delayed_Freeze (E) then
3827 -- If a freeze node is already allocated, use it, otherwise allocate
3828 -- a new one. The preallocation happens in the case of anonymous base
3829 -- types, where we preallocate so that we can set First_Subtype_Link.
3830 -- Note that we reset the Sloc to the current freeze location.
3832 if Present (Freeze_Node (E)) then
3833 F_Node := Freeze_Node (E);
3834 Set_Sloc (F_Node, Loc);
3837 F_Node := New_Node (N_Freeze_Entity, Loc);
3838 Set_Freeze_Node (E, F_Node);
3839 Set_Access_Types_To_Process (F_Node, No_Elist);
3840 Set_TSS_Elist (F_Node, No_Elist);
3841 Set_Actions (F_Node, No_List);
3844 Set_Entity (F_Node, E);
3846 if Result = No_List then
3847 Result := New_List (F_Node);
3849 Append (F_Node, Result);
3852 -- A final pass over record types with discriminants. If the type
3853 -- has an incomplete declaration, there may be constrained access
3854 -- subtypes declared elsewhere, which do not depend on the discrimi-
3855 -- nants of the type, and which are used as component types (i.e.
3856 -- the full view is a recursive type). The designated types of these
3857 -- subtypes can only be elaborated after the type itself, and they
3858 -- need an itype reference.
3860 if Ekind (E) = E_Record_Type
3861 and then Has_Discriminants (E)
3869 Comp := First_Component (E);
3871 while Present (Comp) loop
3872 Typ := Etype (Comp);
3874 if Ekind (Comp) = E_Component
3875 and then Is_Access_Type (Typ)
3876 and then Scope (Typ) /= E
3877 and then Base_Type (Designated_Type (Typ)) = E
3878 and then Is_Itype (Designated_Type (Typ))
3880 IR := Make_Itype_Reference (Sloc (Comp));
3881 Set_Itype (IR, Designated_Type (Typ));
3882 Append (IR, Result);
3885 Next_Component (Comp);
3891 -- When a type is frozen, the first subtype of the type is frozen as
3892 -- well (RM 13.14(15)). This has to be done after freezing the type,
3893 -- since obviously the first subtype depends on its own base type.
3896 Freeze_And_Append (First_Subtype (E), Loc, Result);
3898 -- If we just froze a tagged non-class wide record, then freeze the
3899 -- corresponding class-wide type. This must be done after the tagged
3900 -- type itself is frozen, because the class-wide type refers to the
3901 -- tagged type which generates the class.
3903 if Is_Tagged_Type (E)
3904 and then not Is_Class_Wide_Type (E)
3905 and then Present (Class_Wide_Type (E))
3907 Freeze_And_Append (Class_Wide_Type (E), Loc, Result);
3911 Check_Debug_Info_Needed (E);
3913 -- Special handling for subprograms
3915 if Is_Subprogram (E) then
3917 -- If subprogram has address clause then reset Is_Public flag, since
3918 -- we do not want the backend to generate external references.
3920 if Present (Address_Clause (E))
3921 and then not Is_Library_Level_Entity (E)
3923 Set_Is_Public (E, False);
3925 -- If no address clause and not intrinsic, then for imported
3926 -- subprogram in main unit, generate descriptor if we are in
3927 -- Propagate_Exceptions mode.
3929 elsif Propagate_Exceptions
3930 and then Is_Imported (E)
3931 and then not Is_Intrinsic_Subprogram (E)
3932 and then Convention (E) /= Convention_Stubbed
3934 if Result = No_List then
3935 Result := Empty_List;
3943 -----------------------------
3944 -- Freeze_Enumeration_Type --
3945 -----------------------------
3947 procedure Freeze_Enumeration_Type (Typ : Entity_Id) is
3949 -- By default, if no size clause is present, an enumeration type with
3950 -- Convention C is assumed to interface to a C enum, and has integer
3951 -- size. This applies to types. For subtypes, verify that its base
3952 -- type has no size clause either.
3954 if Has_Foreign_Convention (Typ)
3955 and then not Has_Size_Clause (Typ)
3956 and then not Has_Size_Clause (Base_Type (Typ))
3957 and then Esize (Typ) < Standard_Integer_Size
3959 Init_Esize (Typ, Standard_Integer_Size);
3962 -- If the enumeration type interfaces to C, and it has a size clause
3963 -- that specifies less than int size, it warrants a warning. The
3964 -- user may intend the C type to be an enum or a char, so this is
3965 -- not by itself an error that the Ada compiler can detect, but it
3966 -- it is a worth a heads-up. For Boolean and Character types we
3967 -- assume that the programmer has the proper C type in mind.
3969 if Convention (Typ) = Convention_C
3970 and then Has_Size_Clause (Typ)
3971 and then Esize (Typ) /= Esize (Standard_Integer)
3972 and then not Is_Boolean_Type (Typ)
3973 and then not Is_Character_Type (Typ)
3976 ("C enum types have the size of a C int?", Size_Clause (Typ));
3979 Adjust_Esize_For_Alignment (Typ);
3981 end Freeze_Enumeration_Type;
3983 -----------------------
3984 -- Freeze_Expression --
3985 -----------------------
3987 procedure Freeze_Expression (N : Node_Id) is
3988 In_Spec_Exp : constant Boolean := In_Spec_Expression;
3991 Desig_Typ : Entity_Id;
3995 Freeze_Outside : Boolean := False;
3996 -- This flag is set true if the entity must be frozen outside the
3997 -- current subprogram. This happens in the case of expander generated
3998 -- subprograms (_Init_Proc, _Input, _Output, _Read, _Write) which do
3999 -- not freeze all entities like other bodies, but which nevertheless
4000 -- may reference entities that have to be frozen before the body and
4001 -- obviously cannot be frozen inside the body.
4003 function In_Exp_Body (N : Node_Id) return Boolean;
4004 -- Given an N_Handled_Sequence_Of_Statements node N, determines whether
4005 -- it is the handled statement sequence of an expander-generated
4006 -- subprogram (init proc, stream subprogram, or renaming as body).
4007 -- If so, this is not a freezing context.
4013 function In_Exp_Body (N : Node_Id) return Boolean is
4018 if Nkind (N) = N_Subprogram_Body then
4024 if Nkind (P) /= N_Subprogram_Body then
4028 Id := Defining_Unit_Name (Specification (P));
4030 if Nkind (Id) = N_Defining_Identifier
4031 and then (Is_Init_Proc (Id) or else
4032 Is_TSS (Id, TSS_Stream_Input) or else
4033 Is_TSS (Id, TSS_Stream_Output) or else
4034 Is_TSS (Id, TSS_Stream_Read) or else
4035 Is_TSS (Id, TSS_Stream_Write) or else
4036 Nkind (Original_Node (P)) =
4037 N_Subprogram_Renaming_Declaration)
4046 -- Start of processing for Freeze_Expression
4049 -- Immediate return if freezing is inhibited. This flag is set by the
4050 -- analyzer to stop freezing on generated expressions that would cause
4051 -- freezing if they were in the source program, but which are not
4052 -- supposed to freeze, since they are created.
4054 if Must_Not_Freeze (N) then
4058 -- If expression is non-static, then it does not freeze in a default
4059 -- expression, see section "Handling of Default Expressions" in the
4060 -- spec of package Sem for further details. Note that we have to
4061 -- make sure that we actually have a real expression (if we have
4062 -- a subtype indication, we can't test Is_Static_Expression!)
4065 and then Nkind (N) in N_Subexpr
4066 and then not Is_Static_Expression (N)
4071 -- Freeze type of expression if not frozen already
4075 if Nkind (N) in N_Has_Etype then
4076 if not Is_Frozen (Etype (N)) then
4079 -- Base type may be an derived numeric type that is frozen at
4080 -- the point of declaration, but first_subtype is still unfrozen.
4082 elsif not Is_Frozen (First_Subtype (Etype (N))) then
4083 Typ := First_Subtype (Etype (N));
4087 -- For entity name, freeze entity if not frozen already. A special
4088 -- exception occurs for an identifier that did not come from source.
4089 -- We don't let such identifiers freeze a non-internal entity, i.e.
4090 -- an entity that did come from source, since such an identifier was
4091 -- generated by the expander, and cannot have any semantic effect on
4092 -- the freezing semantics. For example, this stops the parameter of
4093 -- an initialization procedure from freezing the variable.
4095 if Is_Entity_Name (N)
4096 and then not Is_Frozen (Entity (N))
4097 and then (Nkind (N) /= N_Identifier
4098 or else Comes_From_Source (N)
4099 or else not Comes_From_Source (Entity (N)))
4106 -- For an allocator freeze designated type if not frozen already
4108 -- For an aggregate whose component type is an access type, freeze the
4109 -- designated type now, so that its freeze does not appear within the
4110 -- loop that might be created in the expansion of the aggregate. If the
4111 -- designated type is a private type without full view, the expression
4112 -- cannot contain an allocator, so the type is not frozen.
4114 -- For a function, we freeze the entity when the subprogram declaration
4115 -- is frozen, but a function call may appear in an initialization proc.
4116 -- before the declaration is frozen. We need to generate the extra
4117 -- formals, if any, to ensure that the expansion of the call includes
4118 -- the proper actuals. This only applies to Ada subprograms, not to
4125 Desig_Typ := Designated_Type (Etype (N));
4128 if Is_Array_Type (Etype (N))
4129 and then Is_Access_Type (Component_Type (Etype (N)))
4131 Desig_Typ := Designated_Type (Component_Type (Etype (N)));
4134 when N_Selected_Component |
4135 N_Indexed_Component |
4138 if Is_Access_Type (Etype (Prefix (N))) then
4139 Desig_Typ := Designated_Type (Etype (Prefix (N)));
4142 when N_Identifier =>
4144 and then Ekind (Nam) = E_Function
4145 and then Nkind (Parent (N)) = N_Function_Call
4146 and then Convention (Nam) = Convention_Ada
4148 Create_Extra_Formals (Nam);
4155 if Desig_Typ /= Empty
4156 and then (Is_Frozen (Desig_Typ)
4157 or else (not Is_Fully_Defined (Desig_Typ)))
4162 -- All done if nothing needs freezing
4166 and then No (Desig_Typ)
4171 -- Loop for looking at the right place to insert the freeze nodes,
4172 -- exiting from the loop when it is appropriate to insert the freeze
4173 -- node before the current node P.
4175 -- Also checks some special exceptions to the freezing rules. These
4176 -- cases result in a direct return, bypassing the freeze action.
4180 Parent_P := Parent (P);
4182 -- If we don't have a parent, then we are not in a well-formed tree.
4183 -- This is an unusual case, but there are some legitimate situations
4184 -- in which this occurs, notably when the expressions in the range of
4185 -- a type declaration are resolved. We simply ignore the freeze
4186 -- request in this case. Is this right ???
4188 if No (Parent_P) then
4192 -- See if we have got to an appropriate point in the tree
4194 case Nkind (Parent_P) is
4196 -- A special test for the exception of (RM 13.14(8)) for the case
4197 -- of per-object expressions (RM 3.8(18)) occurring in component
4198 -- definition or a discrete subtype definition. Note that we test
4199 -- for a component declaration which includes both cases we are
4200 -- interested in, and furthermore the tree does not have explicit
4201 -- nodes for either of these two constructs.
4203 when N_Component_Declaration =>
4205 -- The case we want to test for here is an identifier that is
4206 -- a per-object expression, this is either a discriminant that
4207 -- appears in a context other than the component declaration
4208 -- or it is a reference to the type of the enclosing construct.
4210 -- For either of these cases, we skip the freezing
4212 if not In_Spec_Expression
4213 and then Nkind (N) = N_Identifier
4214 and then (Present (Entity (N)))
4216 -- We recognize the discriminant case by just looking for
4217 -- a reference to a discriminant. It can only be one for
4218 -- the enclosing construct. Skip freezing in this case.
4220 if Ekind (Entity (N)) = E_Discriminant then
4223 -- For the case of a reference to the enclosing record,
4224 -- (or task or protected type), we look for a type that
4225 -- matches the current scope.
4227 elsif Entity (N) = Current_Scope then
4232 -- If we have an enumeration literal that appears as the choice in
4233 -- the aggregate of an enumeration representation clause, then
4234 -- freezing does not occur (RM 13.14(10)).
4236 when N_Enumeration_Representation_Clause =>
4238 -- The case we are looking for is an enumeration literal
4240 if (Nkind (N) = N_Identifier or Nkind (N) = N_Character_Literal)
4241 and then Is_Enumeration_Type (Etype (N))
4243 -- If enumeration literal appears directly as the choice,
4244 -- do not freeze (this is the normal non-overloaded case)
4246 if Nkind (Parent (N)) = N_Component_Association
4247 and then First (Choices (Parent (N))) = N
4251 -- If enumeration literal appears as the name of function
4252 -- which is the choice, then also do not freeze. This
4253 -- happens in the overloaded literal case, where the
4254 -- enumeration literal is temporarily changed to a function
4255 -- call for overloading analysis purposes.
4257 elsif Nkind (Parent (N)) = N_Function_Call
4259 Nkind (Parent (Parent (N))) = N_Component_Association
4261 First (Choices (Parent (Parent (N)))) = Parent (N)
4267 -- Normally if the parent is a handled sequence of statements,
4268 -- then the current node must be a statement, and that is an
4269 -- appropriate place to insert a freeze node.
4271 when N_Handled_Sequence_Of_Statements =>
4273 -- An exception occurs when the sequence of statements is for
4274 -- an expander generated body that did not do the usual freeze
4275 -- all operation. In this case we usually want to freeze
4276 -- outside this body, not inside it, and we skip past the
4277 -- subprogram body that we are inside.
4279 if In_Exp_Body (Parent_P) then
4281 -- However, we *do* want to freeze at this point if we have
4282 -- an entity to freeze, and that entity is declared *inside*
4283 -- the body of the expander generated procedure. This case
4284 -- is recognized by the scope of the type, which is either
4285 -- the spec for some enclosing body, or (in the case of
4286 -- init_procs, for which there are no separate specs) the
4290 Subp : constant Node_Id := Parent (Parent_P);
4294 if Nkind (Subp) = N_Subprogram_Body then
4295 Cspc := Corresponding_Spec (Subp);
4297 if (Present (Typ) and then Scope (Typ) = Cspc)
4299 (Present (Nam) and then Scope (Nam) = Cspc)
4304 and then Scope (Typ) = Current_Scope
4305 and then Current_Scope = Defining_Entity (Subp)
4312 -- If not that exception to the exception, then this is
4313 -- where we delay the freeze till outside the body.
4315 Parent_P := Parent (Parent_P);
4316 Freeze_Outside := True;
4318 -- Here if normal case where we are in handled statement
4319 -- sequence and want to do the insertion right there.
4325 -- If parent is a body or a spec or a block, then the current node
4326 -- is a statement or declaration and we can insert the freeze node
4329 when N_Package_Specification |
4335 N_Block_Statement => exit;
4337 -- The expander is allowed to define types in any statements list,
4338 -- so any of the following parent nodes also mark a freezing point
4339 -- if the actual node is in a list of statements or declarations.
4341 when N_Exception_Handler |
4344 N_Case_Statement_Alternative |
4345 N_Compilation_Unit_Aux |
4346 N_Selective_Accept |
4347 N_Accept_Alternative |
4348 N_Delay_Alternative |
4349 N_Conditional_Entry_Call |
4350 N_Entry_Call_Alternative |
4351 N_Triggering_Alternative |
4357 exit when Is_List_Member (P);
4359 -- Note: The N_Loop_Statement is a special case. A type that
4360 -- appears in the source can never be frozen in a loop (this
4361 -- occurs only because of a loop expanded by the expander), so we
4362 -- keep on going. Otherwise we terminate the search. Same is true
4363 -- of any entity which comes from source. (if they have predefined
4364 -- type, that type does not appear to come from source, but the
4365 -- entity should not be frozen here).
4367 when N_Loop_Statement =>
4368 exit when not Comes_From_Source (Etype (N))
4369 and then (No (Nam) or else not Comes_From_Source (Nam));
4371 -- For all other cases, keep looking at parents
4377 -- We fall through the case if we did not yet find the proper
4378 -- place in the free for inserting the freeze node, so climb!
4383 -- If the expression appears in a record or an initialization procedure,
4384 -- the freeze nodes are collected and attached to the current scope, to
4385 -- be inserted and analyzed on exit from the scope, to insure that
4386 -- generated entities appear in the correct scope. If the expression is
4387 -- a default for a discriminant specification, the scope is still void.
4388 -- The expression can also appear in the discriminant part of a private
4389 -- or concurrent type.
4391 -- If the expression appears in a constrained subcomponent of an
4392 -- enclosing record declaration, the freeze nodes must be attached to
4393 -- the outer record type so they can eventually be placed in the
4394 -- enclosing declaration list.
4396 -- The other case requiring this special handling is if we are in a
4397 -- default expression, since in that case we are about to freeze a
4398 -- static type, and the freeze scope needs to be the outer scope, not
4399 -- the scope of the subprogram with the default parameter.
4401 -- For default expressions and other spec expressions in generic units,
4402 -- the Move_Freeze_Nodes mechanism (see sem_ch12.adb) takes care of
4403 -- placing them at the proper place, after the generic unit.
4405 if (In_Spec_Exp and not Inside_A_Generic)
4406 or else Freeze_Outside
4407 or else (Is_Type (Current_Scope)
4408 and then (not Is_Concurrent_Type (Current_Scope)
4409 or else not Has_Completion (Current_Scope)))
4410 or else Ekind (Current_Scope) = E_Void
4413 Loc : constant Source_Ptr := Sloc (Current_Scope);
4414 Freeze_Nodes : List_Id := No_List;
4415 Pos : Int := Scope_Stack.Last;
4418 if Present (Desig_Typ) then
4419 Freeze_And_Append (Desig_Typ, Loc, Freeze_Nodes);
4422 if Present (Typ) then
4423 Freeze_And_Append (Typ, Loc, Freeze_Nodes);
4426 if Present (Nam) then
4427 Freeze_And_Append (Nam, Loc, Freeze_Nodes);
4430 -- The current scope may be that of a constrained component of
4431 -- an enclosing record declaration, which is above the current
4432 -- scope in the scope stack.
4434 if Is_Record_Type (Scope (Current_Scope)) then
4438 if Is_Non_Empty_List (Freeze_Nodes) then
4439 if No (Scope_Stack.Table (Pos).Pending_Freeze_Actions) then
4440 Scope_Stack.Table (Pos).Pending_Freeze_Actions :=
4443 Append_List (Freeze_Nodes,
4444 Scope_Stack.Table (Pos).Pending_Freeze_Actions);
4452 -- Now we have the right place to do the freezing. First, a special
4453 -- adjustment, if we are in spec-expression analysis mode, these freeze
4454 -- actions must not be thrown away (normally all inserted actions are
4455 -- thrown away in this mode. However, the freeze actions are from static
4456 -- expressions and one of the important reasons we are doing this
4457 -- special analysis is to get these freeze actions. Therefore we turn
4458 -- off the In_Spec_Expression mode to propagate these freeze actions.
4459 -- This also means they get properly analyzed and expanded.
4461 In_Spec_Expression := False;
4463 -- Freeze the designated type of an allocator (RM 13.14(13))
4465 if Present (Desig_Typ) then
4466 Freeze_Before (P, Desig_Typ);
4469 -- Freeze type of expression (RM 13.14(10)). Note that we took care of
4470 -- the enumeration representation clause exception in the loop above.
4472 if Present (Typ) then
4473 Freeze_Before (P, Typ);
4476 -- Freeze name if one is present (RM 13.14(11))
4478 if Present (Nam) then
4479 Freeze_Before (P, Nam);
4482 -- Restore In_Spec_Expression flag
4484 In_Spec_Expression := In_Spec_Exp;
4485 end Freeze_Expression;
4487 -----------------------------
4488 -- Freeze_Fixed_Point_Type --
4489 -----------------------------
4491 -- Certain fixed-point types and subtypes, including implicit base types
4492 -- and declared first subtypes, have not yet set up a range. This is
4493 -- because the range cannot be set until the Small and Size values are
4494 -- known, and these are not known till the type is frozen.
4496 -- To signal this case, Scalar_Range contains an unanalyzed syntactic range
4497 -- whose bounds are unanalyzed real literals. This routine will recognize
4498 -- this case, and transform this range node into a properly typed range
4499 -- with properly analyzed and resolved values.
4501 procedure Freeze_Fixed_Point_Type (Typ : Entity_Id) is
4502 Rng : constant Node_Id := Scalar_Range (Typ);
4503 Lo : constant Node_Id := Low_Bound (Rng);
4504 Hi : constant Node_Id := High_Bound (Rng);
4505 Btyp : constant Entity_Id := Base_Type (Typ);
4506 Brng : constant Node_Id := Scalar_Range (Btyp);
4507 BLo : constant Node_Id := Low_Bound (Brng);
4508 BHi : constant Node_Id := High_Bound (Brng);
4509 Small : constant Ureal := Small_Value (Typ);
4516 function Fsize (Lov, Hiv : Ureal) return Nat;
4517 -- Returns size of type with given bounds. Also leaves these
4518 -- bounds set as the current bounds of the Typ.
4524 function Fsize (Lov, Hiv : Ureal) return Nat is
4526 Set_Realval (Lo, Lov);
4527 Set_Realval (Hi, Hiv);
4528 return Minimum_Size (Typ);
4531 -- Start of processing for Freeze_Fixed_Point_Type
4534 -- If Esize of a subtype has not previously been set, set it now
4536 if Unknown_Esize (Typ) then
4537 Atype := Ancestor_Subtype (Typ);
4539 if Present (Atype) then
4540 Set_Esize (Typ, Esize (Atype));
4542 Set_Esize (Typ, Esize (Base_Type (Typ)));
4546 -- Immediate return if the range is already analyzed. This means that
4547 -- the range is already set, and does not need to be computed by this
4550 if Analyzed (Rng) then
4554 -- Immediate return if either of the bounds raises Constraint_Error
4556 if Raises_Constraint_Error (Lo)
4557 or else Raises_Constraint_Error (Hi)
4562 Loval := Realval (Lo);
4563 Hival := Realval (Hi);
4565 -- Ordinary fixed-point case
4567 if Is_Ordinary_Fixed_Point_Type (Typ) then
4569 -- For the ordinary fixed-point case, we are allowed to fudge the
4570 -- end-points up or down by small. Generally we prefer to fudge up,
4571 -- i.e. widen the bounds for non-model numbers so that the end points
4572 -- are included. However there are cases in which this cannot be
4573 -- done, and indeed cases in which we may need to narrow the bounds.
4574 -- The following circuit makes the decision.
4576 -- Note: our terminology here is that Incl_EP means that the bounds
4577 -- are widened by Small if necessary to include the end points, and
4578 -- Excl_EP means that the bounds are narrowed by Small to exclude the
4579 -- end-points if this reduces the size.
4581 -- Note that in the Incl case, all we care about is including the
4582 -- end-points. In the Excl case, we want to narrow the bounds as
4583 -- much as permitted by the RM, to give the smallest possible size.
4586 Loval_Incl_EP : Ureal;
4587 Hival_Incl_EP : Ureal;
4589 Loval_Excl_EP : Ureal;
4590 Hival_Excl_EP : Ureal;
4596 First_Subt : Entity_Id;
4601 -- First step. Base types are required to be symmetrical. Right
4602 -- now, the base type range is a copy of the first subtype range.
4603 -- This will be corrected before we are done, but right away we
4604 -- need to deal with the case where both bounds are non-negative.
4605 -- In this case, we set the low bound to the negative of the high
4606 -- bound, to make sure that the size is computed to include the
4607 -- required sign. Note that we do not need to worry about the
4608 -- case of both bounds negative, because the sign will be dealt
4609 -- with anyway. Furthermore we can't just go making such a bound
4610 -- symmetrical, since in a twos-complement system, there is an
4611 -- extra negative value which could not be accommodated on the
4615 and then not UR_Is_Negative (Loval)
4616 and then Hival > Loval
4619 Set_Realval (Lo, Loval);
4622 -- Compute the fudged bounds. If the number is a model number,
4623 -- then we do nothing to include it, but we are allowed to backoff
4624 -- to the next adjacent model number when we exclude it. If it is
4625 -- not a model number then we straddle the two values with the
4626 -- model numbers on either side.
4628 Model_Num := UR_Trunc (Loval / Small) * Small;
4630 if Loval = Model_Num then
4631 Loval_Incl_EP := Model_Num;
4633 Loval_Incl_EP := Model_Num - Small;
4636 -- The low value excluding the end point is Small greater, but
4637 -- we do not do this exclusion if the low value is positive,
4638 -- since it can't help the size and could actually hurt by
4639 -- crossing the high bound.
4641 if UR_Is_Negative (Loval_Incl_EP) then
4642 Loval_Excl_EP := Loval_Incl_EP + Small;
4644 -- If the value went from negative to zero, then we have the
4645 -- case where Loval_Incl_EP is the model number just below
4646 -- zero, so we want to stick to the negative value for the
4647 -- base type to maintain the condition that the size will
4648 -- include signed values.
4651 and then UR_Is_Zero (Loval_Excl_EP)
4653 Loval_Excl_EP := Loval_Incl_EP;
4657 Loval_Excl_EP := Loval_Incl_EP;
4660 -- Similar processing for upper bound and high value
4662 Model_Num := UR_Trunc (Hival / Small) * Small;
4664 if Hival = Model_Num then
4665 Hival_Incl_EP := Model_Num;
4667 Hival_Incl_EP := Model_Num + Small;
4670 if UR_Is_Positive (Hival_Incl_EP) then
4671 Hival_Excl_EP := Hival_Incl_EP - Small;
4673 Hival_Excl_EP := Hival_Incl_EP;
4676 -- One further adjustment is needed. In the case of subtypes, we
4677 -- cannot go outside the range of the base type, or we get
4678 -- peculiarities, and the base type range is already set. This
4679 -- only applies to the Incl values, since clearly the Excl values
4680 -- are already as restricted as they are allowed to be.
4683 Loval_Incl_EP := UR_Max (Loval_Incl_EP, Realval (BLo));
4684 Hival_Incl_EP := UR_Min (Hival_Incl_EP, Realval (BHi));
4687 -- Get size including and excluding end points
4689 Size_Incl_EP := Fsize (Loval_Incl_EP, Hival_Incl_EP);
4690 Size_Excl_EP := Fsize (Loval_Excl_EP, Hival_Excl_EP);
4692 -- No need to exclude end-points if it does not reduce size
4694 if Fsize (Loval_Incl_EP, Hival_Excl_EP) = Size_Excl_EP then
4695 Loval_Excl_EP := Loval_Incl_EP;
4698 if Fsize (Loval_Excl_EP, Hival_Incl_EP) = Size_Excl_EP then
4699 Hival_Excl_EP := Hival_Incl_EP;
4702 -- Now we set the actual size to be used. We want to use the
4703 -- bounds fudged up to include the end-points but only if this
4704 -- can be done without violating a specifically given size
4705 -- size clause or causing an unacceptable increase in size.
4707 -- Case of size clause given
4709 if Has_Size_Clause (Typ) then
4711 -- Use the inclusive size only if it is consistent with
4712 -- the explicitly specified size.
4714 if Size_Incl_EP <= RM_Size (Typ) then
4715 Actual_Lo := Loval_Incl_EP;
4716 Actual_Hi := Hival_Incl_EP;
4717 Actual_Size := Size_Incl_EP;
4719 -- If the inclusive size is too large, we try excluding
4720 -- the end-points (will be caught later if does not work).
4723 Actual_Lo := Loval_Excl_EP;
4724 Actual_Hi := Hival_Excl_EP;
4725 Actual_Size := Size_Excl_EP;
4728 -- Case of size clause not given
4731 -- If we have a base type whose corresponding first subtype
4732 -- has an explicit size that is large enough to include our
4733 -- end-points, then do so. There is no point in working hard
4734 -- to get a base type whose size is smaller than the specified
4735 -- size of the first subtype.
4737 First_Subt := First_Subtype (Typ);
4739 if Has_Size_Clause (First_Subt)
4740 and then Size_Incl_EP <= Esize (First_Subt)
4742 Actual_Size := Size_Incl_EP;
4743 Actual_Lo := Loval_Incl_EP;
4744 Actual_Hi := Hival_Incl_EP;
4746 -- If excluding the end-points makes the size smaller and
4747 -- results in a size of 8,16,32,64, then we take the smaller
4748 -- size. For the 64 case, this is compulsory. For the other
4749 -- cases, it seems reasonable. We like to include end points
4750 -- if we can, but not at the expense of moving to the next
4751 -- natural boundary of size.
4753 elsif Size_Incl_EP /= Size_Excl_EP
4755 (Size_Excl_EP = 8 or else
4756 Size_Excl_EP = 16 or else
4757 Size_Excl_EP = 32 or else
4760 Actual_Size := Size_Excl_EP;
4761 Actual_Lo := Loval_Excl_EP;
4762 Actual_Hi := Hival_Excl_EP;
4764 -- Otherwise we can definitely include the end points
4767 Actual_Size := Size_Incl_EP;
4768 Actual_Lo := Loval_Incl_EP;
4769 Actual_Hi := Hival_Incl_EP;
4772 -- One pathological case: normally we never fudge a low bound
4773 -- down, since it would seem to increase the size (if it has
4774 -- any effect), but for ranges containing single value, or no
4775 -- values, the high bound can be small too large. Consider:
4777 -- type t is delta 2.0**(-14)
4778 -- range 131072.0 .. 0;
4780 -- That lower bound is *just* outside the range of 32 bits, and
4781 -- does need fudging down in this case. Note that the bounds
4782 -- will always have crossed here, since the high bound will be
4783 -- fudged down if necessary, as in the case of:
4785 -- type t is delta 2.0**(-14)
4786 -- range 131072.0 .. 131072.0;
4788 -- So we detect the situation by looking for crossed bounds,
4789 -- and if the bounds are crossed, and the low bound is greater
4790 -- than zero, we will always back it off by small, since this
4791 -- is completely harmless.
4793 if Actual_Lo > Actual_Hi then
4794 if UR_Is_Positive (Actual_Lo) then
4795 Actual_Lo := Loval_Incl_EP - Small;
4796 Actual_Size := Fsize (Actual_Lo, Actual_Hi);
4798 -- And of course, we need to do exactly the same parallel
4799 -- fudge for flat ranges in the negative region.
4801 elsif UR_Is_Negative (Actual_Hi) then
4802 Actual_Hi := Hival_Incl_EP + Small;
4803 Actual_Size := Fsize (Actual_Lo, Actual_Hi);
4808 Set_Realval (Lo, Actual_Lo);
4809 Set_Realval (Hi, Actual_Hi);
4812 -- For the decimal case, none of this fudging is required, since there
4813 -- are no end-point problems in the decimal case (the end-points are
4814 -- always included).
4817 Actual_Size := Fsize (Loval, Hival);
4820 -- At this stage, the actual size has been calculated and the proper
4821 -- required bounds are stored in the low and high bounds.
4823 if Actual_Size > 64 then
4824 Error_Msg_Uint_1 := UI_From_Int (Actual_Size);
4826 ("size required (^) for type& too large, maximum allowed is 64",
4831 -- Check size against explicit given size
4833 if Has_Size_Clause (Typ) then
4834 if Actual_Size > RM_Size (Typ) then
4835 Error_Msg_Uint_1 := RM_Size (Typ);
4836 Error_Msg_Uint_2 := UI_From_Int (Actual_Size);
4838 ("size given (^) for type& too small, minimum allowed is ^",
4839 Size_Clause (Typ), Typ);
4842 Actual_Size := UI_To_Int (Esize (Typ));
4845 -- Increase size to next natural boundary if no size clause given
4848 if Actual_Size <= 8 then
4850 elsif Actual_Size <= 16 then
4852 elsif Actual_Size <= 32 then
4858 Init_Esize (Typ, Actual_Size);
4859 Adjust_Esize_For_Alignment (Typ);
4862 -- If we have a base type, then expand the bounds so that they extend to
4863 -- the full width of the allocated size in bits, to avoid junk range
4864 -- checks on intermediate computations.
4866 if Base_Type (Typ) = Typ then
4867 Set_Realval (Lo, -(Small * (Uint_2 ** (Actual_Size - 1))));
4868 Set_Realval (Hi, (Small * (Uint_2 ** (Actual_Size - 1) - 1)));
4871 -- Final step is to reanalyze the bounds using the proper type
4872 -- and set the Corresponding_Integer_Value fields of the literals.
4874 Set_Etype (Lo, Empty);
4875 Set_Analyzed (Lo, False);
4878 -- Resolve with universal fixed if the base type, and the base type if
4879 -- it is a subtype. Note we can't resolve the base type with itself,
4880 -- that would be a reference before definition.
4883 Resolve (Lo, Universal_Fixed);
4888 -- Set corresponding integer value for bound
4890 Set_Corresponding_Integer_Value
4891 (Lo, UR_To_Uint (Realval (Lo) / Small));
4893 -- Similar processing for high bound
4895 Set_Etype (Hi, Empty);
4896 Set_Analyzed (Hi, False);
4900 Resolve (Hi, Universal_Fixed);
4905 Set_Corresponding_Integer_Value
4906 (Hi, UR_To_Uint (Realval (Hi) / Small));
4908 -- Set type of range to correspond to bounds
4910 Set_Etype (Rng, Etype (Lo));
4912 -- Set Esize to calculated size if not set already
4914 if Unknown_Esize (Typ) then
4915 Init_Esize (Typ, Actual_Size);
4918 -- Set RM_Size if not already set. If already set, check value
4921 Minsiz : constant Uint := UI_From_Int (Minimum_Size (Typ));
4924 if RM_Size (Typ) /= Uint_0 then
4925 if RM_Size (Typ) < Minsiz then
4926 Error_Msg_Uint_1 := RM_Size (Typ);
4927 Error_Msg_Uint_2 := Minsiz;
4929 ("size given (^) for type& too small, minimum allowed is ^",
4930 Size_Clause (Typ), Typ);
4934 Set_RM_Size (Typ, Minsiz);
4937 end Freeze_Fixed_Point_Type;
4943 procedure Freeze_Itype (T : Entity_Id; N : Node_Id) is
4947 Set_Has_Delayed_Freeze (T);
4948 L := Freeze_Entity (T, Sloc (N));
4950 if Is_Non_Empty_List (L) then
4951 Insert_Actions (N, L);
4955 --------------------------
4956 -- Freeze_Static_Object --
4957 --------------------------
4959 procedure Freeze_Static_Object (E : Entity_Id) is
4961 Cannot_Be_Static : exception;
4962 -- Exception raised if the type of a static object cannot be made
4963 -- static. This happens if the type depends on non-global objects.
4965 procedure Ensure_Expression_Is_SA (N : Node_Id);
4966 -- Called to ensure that an expression used as part of a type definition
4967 -- is statically allocatable, which means that the expression type is
4968 -- statically allocatable, and the expression is either static, or a
4969 -- reference to a library level constant.
4971 procedure Ensure_Type_Is_SA (Typ : Entity_Id);
4972 -- Called to mark a type as static, checking that it is possible
4973 -- to set the type as static. If it is not possible, then the
4974 -- exception Cannot_Be_Static is raised.
4976 -----------------------------
4977 -- Ensure_Expression_Is_SA --
4978 -----------------------------
4980 procedure Ensure_Expression_Is_SA (N : Node_Id) is
4984 Ensure_Type_Is_SA (Etype (N));
4986 if Is_Static_Expression (N) then
4989 elsif Nkind (N) = N_Identifier then
4993 and then Ekind (Ent) = E_Constant
4994 and then Is_Library_Level_Entity (Ent)
5000 raise Cannot_Be_Static;
5001 end Ensure_Expression_Is_SA;
5003 -----------------------
5004 -- Ensure_Type_Is_SA --
5005 -----------------------
5007 procedure Ensure_Type_Is_SA (Typ : Entity_Id) is
5012 -- If type is library level, we are all set
5014 if Is_Library_Level_Entity (Typ) then
5018 -- We are also OK if the type already marked as statically allocated,
5019 -- which means we processed it before.
5021 if Is_Statically_Allocated (Typ) then
5025 -- Mark type as statically allocated
5027 Set_Is_Statically_Allocated (Typ);
5029 -- Check that it is safe to statically allocate this type
5031 if Is_Scalar_Type (Typ) or else Is_Real_Type (Typ) then
5032 Ensure_Expression_Is_SA (Type_Low_Bound (Typ));
5033 Ensure_Expression_Is_SA (Type_High_Bound (Typ));
5035 elsif Is_Array_Type (Typ) then
5036 N := First_Index (Typ);
5037 while Present (N) loop
5038 Ensure_Type_Is_SA (Etype (N));
5042 Ensure_Type_Is_SA (Component_Type (Typ));
5044 elsif Is_Access_Type (Typ) then
5045 if Ekind (Designated_Type (Typ)) = E_Subprogram_Type then
5049 T : constant Entity_Id := Etype (Designated_Type (Typ));
5052 if T /= Standard_Void_Type then
5053 Ensure_Type_Is_SA (T);
5056 F := First_Formal (Designated_Type (Typ));
5058 while Present (F) loop
5059 Ensure_Type_Is_SA (Etype (F));
5065 Ensure_Type_Is_SA (Designated_Type (Typ));
5068 elsif Is_Record_Type (Typ) then
5069 C := First_Entity (Typ);
5070 while Present (C) loop
5071 if Ekind (C) = E_Discriminant
5072 or else Ekind (C) = E_Component
5074 Ensure_Type_Is_SA (Etype (C));
5076 elsif Is_Type (C) then
5077 Ensure_Type_Is_SA (C);
5083 elsif Ekind (Typ) = E_Subprogram_Type then
5084 Ensure_Type_Is_SA (Etype (Typ));
5086 C := First_Formal (Typ);
5087 while Present (C) loop
5088 Ensure_Type_Is_SA (Etype (C));
5093 raise Cannot_Be_Static;
5095 end Ensure_Type_Is_SA;
5097 -- Start of processing for Freeze_Static_Object
5100 Ensure_Type_Is_SA (Etype (E));
5103 when Cannot_Be_Static =>
5105 -- If the object that cannot be static is imported or exported, then
5106 -- issue an error message saying that this object cannot be imported
5107 -- or exported. If it has an address clause it is an overlay in the
5108 -- current partition and the static requirement is not relevant.
5110 if Is_Imported (E) and then No (Address_Clause (E)) then
5112 ("& cannot be imported (local type is not constant)", E);
5114 -- Otherwise must be exported, something is wrong if compiler
5115 -- is marking something as statically allocated which cannot be).
5117 else pragma Assert (Is_Exported (E));
5119 ("& cannot be exported (local type is not constant)", E);
5121 end Freeze_Static_Object;
5123 -----------------------
5124 -- Freeze_Subprogram --
5125 -----------------------
5127 procedure Freeze_Subprogram (E : Entity_Id) is
5132 -- Subprogram may not have an address clause unless it is imported
5134 if Present (Address_Clause (E)) then
5135 if not Is_Imported (E) then
5137 ("address clause can only be given " &
5138 "for imported subprogram",
5139 Name (Address_Clause (E)));
5143 -- Reset the Pure indication on an imported subprogram unless an
5144 -- explicit Pure_Function pragma was present. We do this because
5145 -- otherwise it is an insidious error to call a non-pure function from
5146 -- pure unit and have calls mysteriously optimized away. What happens
5147 -- here is that the Import can bypass the normal check to ensure that
5148 -- pure units call only pure subprograms.
5151 and then Is_Pure (E)
5152 and then not Has_Pragma_Pure_Function (E)
5154 Set_Is_Pure (E, False);
5157 -- For non-foreign convention subprograms, this is where we create
5158 -- the extra formals (for accessibility level and constrained bit
5159 -- information). We delay this till the freeze point precisely so
5160 -- that we know the convention!
5162 if not Has_Foreign_Convention (E) then
5163 Create_Extra_Formals (E);
5166 -- If this is convention Ada and a Valued_Procedure, that's odd
5168 if Ekind (E) = E_Procedure
5169 and then Is_Valued_Procedure (E)
5170 and then Convention (E) = Convention_Ada
5171 and then Warn_On_Export_Import
5174 ("?Valued_Procedure has no effect for convention Ada", E);
5175 Set_Is_Valued_Procedure (E, False);
5178 -- Case of foreign convention
5183 -- For foreign conventions, warn about return of an
5184 -- unconstrained array.
5186 -- Note: we *do* allow a return by descriptor for the VMS case,
5187 -- though here there is probably more to be done ???
5189 if Ekind (E) = E_Function then
5190 Retype := Underlying_Type (Etype (E));
5192 -- If no return type, probably some other error, e.g. a
5193 -- missing full declaration, so ignore.
5198 -- If the return type is generic, we have emitted a warning
5199 -- earlier on, and there is nothing else to check here. Specific
5200 -- instantiations may lead to erroneous behavior.
5202 elsif Is_Generic_Type (Etype (E)) then
5205 -- Display warning if returning unconstrained array
5207 elsif Is_Array_Type (Retype)
5208 and then not Is_Constrained (Retype)
5210 -- Exclude cases where descriptor mechanism is set, since the
5211 -- VMS descriptor mechanisms allow such unconstrained returns.
5213 and then Mechanism (E) not in Descriptor_Codes
5215 -- Check appropriate warning is enabled (should we check for
5216 -- Warnings (Off) on specific entities here, probably so???)
5218 and then Warn_On_Export_Import
5220 -- Exclude the VM case, since return of unconstrained arrays
5221 -- is properly handled in both the JVM and .NET cases.
5223 and then VM_Target = No_VM
5226 ("?foreign convention function& should not return " &
5227 "unconstrained array", E);
5232 -- If any of the formals for an exported foreign convention
5233 -- subprogram have defaults, then emit an appropriate warning since
5234 -- this is odd (default cannot be used from non-Ada code)
5236 if Is_Exported (E) then
5237 F := First_Formal (E);
5238 while Present (F) loop
5239 if Warn_On_Export_Import
5240 and then Present (Default_Value (F))
5243 ("?parameter cannot be defaulted in non-Ada call",
5252 -- For VMS, descriptor mechanisms for parameters are allowed only for
5253 -- imported/exported subprograms. Moreover, the NCA descriptor is not
5254 -- allowed for parameters of exported subprograms.
5256 if OpenVMS_On_Target then
5257 if Is_Exported (E) then
5258 F := First_Formal (E);
5259 while Present (F) loop
5260 if Mechanism (F) = By_Descriptor_NCA then
5262 ("'N'C'A' descriptor for parameter not permitted", F);
5264 ("\can only be used for imported subprogram", F);
5270 elsif not Is_Imported (E) then
5271 F := First_Formal (E);
5272 while Present (F) loop
5273 if Mechanism (F) in Descriptor_Codes then
5275 ("descriptor mechanism for parameter not permitted", F);
5277 ("\can only be used for imported/exported subprogram", F);
5285 -- Pragma Inline_Always is disallowed for dispatching subprograms
5286 -- because the address of such subprograms is saved in the dispatch
5287 -- table to support dispatching calls, and dispatching calls cannot
5288 -- be inlined. This is consistent with the restriction against using
5289 -- 'Access or 'Address on an Inline_Always subprogram.
5291 if Is_Dispatching_Operation (E)
5292 and then Has_Pragma_Inline_Always (E)
5295 ("pragma Inline_Always not allowed for dispatching subprograms", E);
5298 -- Because of the implicit representation of inherited predefined
5299 -- operators in the front-end, the overriding status of the operation
5300 -- may be affected when a full view of a type is analyzed, and this is
5301 -- not captured by the analysis of the corresponding type declaration.
5302 -- Therefore the correctness of a not-overriding indicator must be
5303 -- rechecked when the subprogram is frozen.
5305 if Nkind (E) = N_Defining_Operator_Symbol
5306 and then not Error_Posted (Parent (E))
5308 Check_Overriding_Indicator (E, Empty, Is_Primitive (E));
5310 end Freeze_Subprogram;
5312 ----------------------
5313 -- Is_Fully_Defined --
5314 ----------------------
5316 function Is_Fully_Defined (T : Entity_Id) return Boolean is
5318 if Ekind (T) = E_Class_Wide_Type then
5319 return Is_Fully_Defined (Etype (T));
5321 elsif Is_Array_Type (T) then
5322 return Is_Fully_Defined (Component_Type (T));
5324 elsif Is_Record_Type (T)
5325 and not Is_Private_Type (T)
5327 -- Verify that the record type has no components with private types
5328 -- without completion.
5334 Comp := First_Component (T);
5336 while Present (Comp) loop
5337 if not Is_Fully_Defined (Etype (Comp)) then
5341 Next_Component (Comp);
5346 -- For the designated type of an access to subprogram, all types in
5347 -- the profile must be fully defined.
5349 elsif Ekind (T) = E_Subprogram_Type then
5354 F := First_Formal (T);
5355 while Present (F) loop
5356 if not Is_Fully_Defined (Etype (F)) then
5363 return Is_Fully_Defined (Etype (T));
5367 return not Is_Private_Type (T)
5368 or else Present (Full_View (Base_Type (T)));
5370 end Is_Fully_Defined;
5372 ---------------------------------
5373 -- Process_Default_Expressions --
5374 ---------------------------------
5376 procedure Process_Default_Expressions
5378 After : in out Node_Id)
5380 Loc : constant Source_Ptr := Sloc (E);
5387 Set_Default_Expressions_Processed (E);
5389 -- A subprogram instance and its associated anonymous subprogram share
5390 -- their signature. The default expression functions are defined in the
5391 -- wrapper packages for the anonymous subprogram, and should not be
5392 -- generated again for the instance.
5394 if Is_Generic_Instance (E)
5395 and then Present (Alias (E))
5396 and then Default_Expressions_Processed (Alias (E))
5401 Formal := First_Formal (E);
5402 while Present (Formal) loop
5403 if Present (Default_Value (Formal)) then
5405 -- We work with a copy of the default expression because we
5406 -- do not want to disturb the original, since this would mess
5407 -- up the conformance checking.
5409 Dcopy := New_Copy_Tree (Default_Value (Formal));
5411 -- The analysis of the expression may generate insert actions,
5412 -- which of course must not be executed. We wrap those actions
5413 -- in a procedure that is not called, and later on eliminated.
5414 -- The following cases have no side-effects, and are analyzed
5417 if Nkind (Dcopy) = N_Identifier
5418 or else Nkind (Dcopy) = N_Expanded_Name
5419 or else Nkind (Dcopy) = N_Integer_Literal
5420 or else (Nkind (Dcopy) = N_Real_Literal
5421 and then not Vax_Float (Etype (Dcopy)))
5422 or else Nkind (Dcopy) = N_Character_Literal
5423 or else Nkind (Dcopy) = N_String_Literal
5424 or else Known_Null (Dcopy)
5425 or else (Nkind (Dcopy) = N_Attribute_Reference
5427 Attribute_Name (Dcopy) = Name_Null_Parameter)
5430 -- If there is no default function, we must still do a full
5431 -- analyze call on the default value, to ensure that all error
5432 -- checks are performed, e.g. those associated with static
5433 -- evaluation. Note: this branch will always be taken if the
5434 -- analyzer is turned off (but we still need the error checks).
5436 -- Note: the setting of parent here is to meet the requirement
5437 -- that we can only analyze the expression while attached to
5438 -- the tree. Really the requirement is that the parent chain
5439 -- be set, we don't actually need to be in the tree.
5441 Set_Parent (Dcopy, Declaration_Node (Formal));
5444 -- Default expressions are resolved with their own type if the
5445 -- context is generic, to avoid anomalies with private types.
5447 if Ekind (Scope (E)) = E_Generic_Package then
5450 Resolve (Dcopy, Etype (Formal));
5453 -- If that resolved expression will raise constraint error,
5454 -- then flag the default value as raising constraint error.
5455 -- This allows a proper error message on the calls.
5457 if Raises_Constraint_Error (Dcopy) then
5458 Set_Raises_Constraint_Error (Default_Value (Formal));
5461 -- If the default is a parameterless call, we use the name of
5462 -- the called function directly, and there is no body to build.
5464 elsif Nkind (Dcopy) = N_Function_Call
5465 and then No (Parameter_Associations (Dcopy))
5469 -- Else construct and analyze the body of a wrapper procedure
5470 -- that contains an object declaration to hold the expression.
5471 -- Given that this is done only to complete the analysis, it
5472 -- simpler to build a procedure than a function which might
5473 -- involve secondary stack expansion.
5476 Dnam := Make_Temporary (Loc, 'D');
5479 Make_Subprogram_Body (Loc,
5481 Make_Procedure_Specification (Loc,
5482 Defining_Unit_Name => Dnam),
5484 Declarations => New_List (
5485 Make_Object_Declaration (Loc,
5486 Defining_Identifier =>
5487 Make_Defining_Identifier (Loc,
5488 New_Internal_Name ('T')),
5489 Object_Definition =>
5490 New_Occurrence_Of (Etype (Formal), Loc),
5491 Expression => New_Copy_Tree (Dcopy))),
5493 Handled_Statement_Sequence =>
5494 Make_Handled_Sequence_Of_Statements (Loc,
5495 Statements => New_List));
5497 Set_Scope (Dnam, Scope (E));
5498 Set_Assignment_OK (First (Declarations (Dbody)));
5499 Set_Is_Eliminated (Dnam);
5500 Insert_After (After, Dbody);
5506 Next_Formal (Formal);
5508 end Process_Default_Expressions;
5510 ----------------------------------------
5511 -- Set_Component_Alignment_If_Not_Set --
5512 ----------------------------------------
5514 procedure Set_Component_Alignment_If_Not_Set (Typ : Entity_Id) is
5516 -- Ignore if not base type, subtypes don't need anything
5518 if Typ /= Base_Type (Typ) then
5522 -- Do not override existing representation
5524 if Is_Packed (Typ) then
5527 elsif Has_Specified_Layout (Typ) then
5530 elsif Component_Alignment (Typ) /= Calign_Default then
5534 Set_Component_Alignment
5535 (Typ, Scope_Stack.Table
5536 (Scope_Stack.Last).Component_Alignment_Default);
5538 end Set_Component_Alignment_If_Not_Set;
5544 procedure Undelay_Type (T : Entity_Id) is
5546 Set_Has_Delayed_Freeze (T, False);
5547 Set_Freeze_Node (T, Empty);
5549 -- Since we don't want T to have a Freeze_Node, we don't want its
5550 -- Full_View or Corresponding_Record_Type to have one either.
5552 -- ??? Fundamentally, this whole handling is a kludge. What we really
5553 -- want is to be sure that for an Itype that's part of record R and is a
5554 -- subtype of type T, that it's frozen after the later of the freeze
5555 -- points of R and T. We have no way of doing that directly, so what we
5556 -- do is force most such Itypes to be frozen as part of freezing R via
5557 -- this procedure and only delay the ones that need to be delayed
5558 -- (mostly the designated types of access types that are defined as part
5561 if Is_Private_Type (T)
5562 and then Present (Full_View (T))
5563 and then Is_Itype (Full_View (T))
5564 and then Is_Record_Type (Scope (Full_View (T)))
5566 Undelay_Type (Full_View (T));
5569 if Is_Concurrent_Type (T)
5570 and then Present (Corresponding_Record_Type (T))
5571 and then Is_Itype (Corresponding_Record_Type (T))
5572 and then Is_Record_Type (Scope (Corresponding_Record_Type (T)))
5574 Undelay_Type (Corresponding_Record_Type (T));
5582 procedure Warn_Overlay
5587 Ent : constant Entity_Id := Entity (Nam);
5588 -- The object to which the address clause applies
5591 Old : Entity_Id := Empty;
5595 -- No warning if address clause overlay warnings are off
5597 if not Address_Clause_Overlay_Warnings then
5601 -- No warning if there is an explicit initialization
5603 Init := Original_Node (Expression (Declaration_Node (Ent)));
5605 if Present (Init) and then Comes_From_Source (Init) then
5609 -- We only give the warning for non-imported entities of a type for
5610 -- which a non-null base init proc is defined, or for objects of access
5611 -- types with implicit null initialization, or when Normalize_Scalars
5612 -- applies and the type is scalar or a string type (the latter being
5613 -- tested for because predefined String types are initialized by inline
5614 -- code rather than by an init_proc). Note that we do not give the
5615 -- warning for Initialize_Scalars, since we suppressed initialization
5619 and then not Is_Imported (Ent)
5620 and then (Has_Non_Null_Base_Init_Proc (Typ)
5621 or else Is_Access_Type (Typ)
5622 or else (Normalize_Scalars
5623 and then (Is_Scalar_Type (Typ)
5624 or else Is_String_Type (Typ))))
5626 if Nkind (Expr) = N_Attribute_Reference
5627 and then Is_Entity_Name (Prefix (Expr))
5629 Old := Entity (Prefix (Expr));
5631 elsif Is_Entity_Name (Expr)
5632 and then Ekind (Entity (Expr)) = E_Constant
5634 Decl := Declaration_Node (Entity (Expr));
5636 if Nkind (Decl) = N_Object_Declaration
5637 and then Present (Expression (Decl))
5638 and then Nkind (Expression (Decl)) = N_Attribute_Reference
5639 and then Is_Entity_Name (Prefix (Expression (Decl)))
5641 Old := Entity (Prefix (Expression (Decl)));
5643 elsif Nkind (Expr) = N_Function_Call then
5647 -- A function call (most likely to To_Address) is probably not an
5648 -- overlay, so skip warning. Ditto if the function call was inlined
5649 -- and transformed into an entity.
5651 elsif Nkind (Original_Node (Expr)) = N_Function_Call then
5655 Decl := Next (Parent (Expr));
5657 -- If a pragma Import follows, we assume that it is for the current
5658 -- target of the address clause, and skip the warning.
5661 and then Nkind (Decl) = N_Pragma
5662 and then Pragma_Name (Decl) = Name_Import
5667 if Present (Old) then
5668 Error_Msg_Node_2 := Old;
5670 ("default initialization of & may modify &?",
5674 ("default initialization of & may modify overlaid storage?",
5678 -- Add friendly warning if initialization comes from a packed array
5681 if Is_Record_Type (Typ) then
5686 Comp := First_Component (Typ);
5688 while Present (Comp) loop
5689 if Nkind (Parent (Comp)) = N_Component_Declaration
5690 and then Present (Expression (Parent (Comp)))
5693 elsif Is_Array_Type (Etype (Comp))
5694 and then Present (Packed_Array_Type (Etype (Comp)))
5697 ("\packed array component& " &
5698 "will be initialized to zero?",
5702 Next_Component (Comp);
5709 ("\use pragma Import for & to " &
5710 "suppress initialization (RM B.1(24))?",
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