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;
214 -- If the renamed subprogram is intrinsic, there is no need for a
215 -- wrapper body: we set the alias that will be called and expanded which
216 -- completes the declaration. This transformation is only legal if the
217 -- renamed entity has already been elaborated.
219 -- Note that it is legal for a renaming_as_body to rename an intrinsic
220 -- subprogram, as long as the renaming occurs before the new entity
221 -- is frozen. See RM 8.5.4 (5).
223 if Nkind (Body_Decl) = N_Subprogram_Renaming_Declaration
224 and then Is_Entity_Name (Name (Body_Decl))
226 Renamed_Subp := Entity (Name (Body_Decl));
228 Renamed_Subp := Empty;
231 if Present (Renamed_Subp)
232 and then Is_Intrinsic_Subprogram (Renamed_Subp)
234 (not In_Same_Source_Unit (Renamed_Subp, Ent)
235 or else Sloc (Renamed_Subp) < Sloc (Ent))
238 -- We can make the renaming entity intrisic if the renamed function
239 -- has an interface name, or it is one of the shift/rotate operations
240 -- known to the compiler.
242 (Present (Interface_Name (Renamed_Subp))
243 or else Chars (Renamed_Subp) = Name_Rotate_Left
244 or else Chars (Renamed_Subp) = Name_Rotate_Right
245 or else Chars (Renamed_Subp) = Name_Shift_Left
246 or else Chars (Renamed_Subp) = Name_Shift_Right
247 or else Chars (Renamed_Subp) = Name_Shift_Right_Arithmetic)
249 Set_Interface_Name (Ent, Interface_Name (Renamed_Subp));
250 if Present (Alias (Renamed_Subp)) then
251 Set_Alias (Ent, Alias (Renamed_Subp));
253 Set_Alias (Ent, Renamed_Subp);
256 Set_Is_Intrinsic_Subprogram (Ent);
257 Set_Has_Completion (Ent);
260 Body_Node := Build_Renamed_Body (Decl, New_S);
261 Insert_After (After, Body_Node);
262 Mark_Rewrite_Insertion (Body_Node);
266 end Build_And_Analyze_Renamed_Body;
268 ------------------------
269 -- Build_Renamed_Body --
270 ------------------------
272 function Build_Renamed_Body
274 New_S : Entity_Id) return Node_Id
276 Loc : constant Source_Ptr := Sloc (New_S);
277 -- We use for the source location of the renamed body, the location
278 -- of the spec entity. It might seem more natural to use the location
279 -- of the renaming declaration itself, but that would be wrong, since
280 -- then the body we create would look as though it was created far
281 -- too late, and this could cause problems with elaboration order
282 -- analysis, particularly in connection with instantiations.
284 N : constant Node_Id := Unit_Declaration_Node (New_S);
285 Nam : constant Node_Id := Name (N);
287 Spec : constant Node_Id := New_Copy_Tree (Specification (Decl));
288 Actuals : List_Id := No_List;
293 O_Formal : Entity_Id;
294 Param_Spec : Node_Id;
296 Pref : Node_Id := Empty;
297 -- If the renamed entity is a primitive operation given in prefix form,
298 -- the prefix is the target object and it has to be added as the first
299 -- actual in the generated call.
302 -- Determine the entity being renamed, which is the target of the call
303 -- statement. If the name is an explicit dereference, this is a renaming
304 -- of a subprogram type rather than a subprogram. The name itself is
307 if Nkind (Nam) = N_Selected_Component then
308 Old_S := Entity (Selector_Name (Nam));
310 elsif Nkind (Nam) = N_Explicit_Dereference then
311 Old_S := Etype (Nam);
313 elsif Nkind (Nam) = N_Indexed_Component then
314 if Is_Entity_Name (Prefix (Nam)) then
315 Old_S := Entity (Prefix (Nam));
317 Old_S := Entity (Selector_Name (Prefix (Nam)));
320 elsif Nkind (Nam) = N_Character_Literal then
321 Old_S := Etype (New_S);
324 Old_S := Entity (Nam);
327 if Is_Entity_Name (Nam) then
329 -- If the renamed entity is a predefined operator, retain full name
330 -- to ensure its visibility.
332 if Ekind (Old_S) = E_Operator
333 and then Nkind (Nam) = N_Expanded_Name
335 Call_Name := New_Copy (Name (N));
337 Call_Name := New_Reference_To (Old_S, Loc);
341 if Nkind (Nam) = N_Selected_Component
342 and then Present (First_Formal (Old_S))
344 (Is_Controlling_Formal (First_Formal (Old_S))
345 or else Is_Class_Wide_Type (Etype (First_Formal (Old_S))))
348 -- Retrieve the target object, to be added as a first actual
351 Call_Name := New_Occurrence_Of (Old_S, Loc);
352 Pref := Prefix (Nam);
355 Call_Name := New_Copy (Name (N));
358 -- The original name may have been overloaded, but
359 -- is fully resolved now.
361 Set_Is_Overloaded (Call_Name, False);
364 -- For simple renamings, subsequent calls can be expanded directly as
365 -- calls to the renamed entity. The body must be generated in any case
366 -- for calls that may appear elsewhere.
368 if (Ekind (Old_S) = E_Function
369 or else Ekind (Old_S) = E_Procedure)
370 and then Nkind (Decl) = N_Subprogram_Declaration
372 Set_Body_To_Inline (Decl, Old_S);
375 -- The body generated for this renaming is an internal artifact, and
376 -- does not constitute a freeze point for the called entity.
378 Set_Must_Not_Freeze (Call_Name);
380 Formal := First_Formal (Defining_Entity (Decl));
382 if Present (Pref) then
384 Pref_Type : constant Entity_Id := Etype (Pref);
385 Form_Type : constant Entity_Id := Etype (First_Formal (Old_S));
389 -- The controlling formal may be an access parameter, or the
390 -- actual may be an access value, so adjust accordingly.
392 if Is_Access_Type (Pref_Type)
393 and then not Is_Access_Type (Form_Type)
396 (Make_Explicit_Dereference (Loc, Relocate_Node (Pref)));
398 elsif Is_Access_Type (Form_Type)
399 and then not Is_Access_Type (Pref)
402 (Make_Attribute_Reference (Loc,
403 Attribute_Name => Name_Access,
404 Prefix => Relocate_Node (Pref)));
406 Actuals := New_List (Pref);
410 elsif Present (Formal) then
417 if Present (Formal) then
418 while Present (Formal) loop
419 Append (New_Reference_To (Formal, Loc), Actuals);
420 Next_Formal (Formal);
424 -- If the renamed entity is an entry, inherit its profile. For other
425 -- renamings as bodies, both profiles must be subtype conformant, so it
426 -- is not necessary to replace the profile given in the declaration.
427 -- However, default values that are aggregates are rewritten when
428 -- partially analyzed, so we recover the original aggregate to insure
429 -- that subsequent conformity checking works. Similarly, if the default
430 -- expression was constant-folded, recover the original expression.
432 Formal := First_Formal (Defining_Entity (Decl));
434 if Present (Formal) then
435 O_Formal := First_Formal (Old_S);
436 Param_Spec := First (Parameter_Specifications (Spec));
438 while Present (Formal) loop
439 if Is_Entry (Old_S) then
441 if Nkind (Parameter_Type (Param_Spec)) /=
444 Set_Etype (Formal, Etype (O_Formal));
445 Set_Entity (Parameter_Type (Param_Spec), Etype (O_Formal));
448 elsif Nkind (Default_Value (O_Formal)) = N_Aggregate
449 or else Nkind (Original_Node (Default_Value (O_Formal))) /=
450 Nkind (Default_Value (O_Formal))
452 Set_Expression (Param_Spec,
453 New_Copy_Tree (Original_Node (Default_Value (O_Formal))));
456 Next_Formal (Formal);
457 Next_Formal (O_Formal);
462 -- If the renamed entity is a function, the generated body contains a
463 -- return statement. Otherwise, build a procedure call. If the entity is
464 -- an entry, subsequent analysis of the call will transform it into the
465 -- proper entry or protected operation call. If the renamed entity is
466 -- a character literal, return it directly.
468 if Ekind (Old_S) = E_Function
469 or else Ekind (Old_S) = E_Operator
470 or else (Ekind (Old_S) = E_Subprogram_Type
471 and then Etype (Old_S) /= Standard_Void_Type)
474 Make_Simple_Return_Statement (Loc,
476 Make_Function_Call (Loc,
478 Parameter_Associations => Actuals));
480 elsif Ekind (Old_S) = E_Enumeration_Literal then
482 Make_Simple_Return_Statement (Loc,
483 Expression => New_Occurrence_Of (Old_S, Loc));
485 elsif Nkind (Nam) = N_Character_Literal then
487 Make_Simple_Return_Statement (Loc,
488 Expression => Call_Name);
492 Make_Procedure_Call_Statement (Loc,
494 Parameter_Associations => Actuals);
497 -- Create entities for subprogram body and formals
499 Set_Defining_Unit_Name (Spec,
500 Make_Defining_Identifier (Loc, Chars => Chars (New_S)));
502 Param_Spec := First (Parameter_Specifications (Spec));
504 while Present (Param_Spec) loop
505 Set_Defining_Identifier (Param_Spec,
506 Make_Defining_Identifier (Loc,
507 Chars => Chars (Defining_Identifier (Param_Spec))));
512 Make_Subprogram_Body (Loc,
513 Specification => Spec,
514 Declarations => New_List,
515 Handled_Statement_Sequence =>
516 Make_Handled_Sequence_Of_Statements (Loc,
517 Statements => New_List (Call_Node)));
519 if Nkind (Decl) /= N_Subprogram_Declaration then
521 Make_Subprogram_Declaration (Loc,
522 Specification => Specification (N)));
525 -- Link the body to the entity whose declaration it completes. If
526 -- the body is analyzed when the renamed entity is frozen, it may
527 -- be necessary to restore the proper scope (see package Exp_Ch13).
529 if Nkind (N) = N_Subprogram_Renaming_Declaration
530 and then Present (Corresponding_Spec (N))
532 Set_Corresponding_Spec (Body_Node, Corresponding_Spec (N));
534 Set_Corresponding_Spec (Body_Node, New_S);
538 end Build_Renamed_Body;
540 --------------------------
541 -- Check_Address_Clause --
542 --------------------------
544 procedure Check_Address_Clause (E : Entity_Id) is
545 Addr : constant Node_Id := Address_Clause (E);
547 Decl : constant Node_Id := Declaration_Node (E);
548 Typ : constant Entity_Id := Etype (E);
551 if Present (Addr) then
552 Expr := Expression (Addr);
554 -- If we have no initialization of any kind, then we don't need to
555 -- place any restrictions on the address clause, because the object
556 -- will be elaborated after the address clause is evaluated. This
557 -- happens if the declaration has no initial expression, or the type
558 -- has no implicit initialization, or the object is imported.
560 -- The same holds for all initialized scalar types and all access
561 -- types. Packed bit arrays of size up to 64 are represented using a
562 -- modular type with an initialization (to zero) and can be processed
563 -- like other initialized scalar types.
565 -- If the type is controlled, code to attach the object to a
566 -- finalization chain is generated at the point of declaration,
567 -- and therefore the elaboration of the object cannot be delayed:
568 -- the address expression must be a constant.
570 if (No (Expression (Decl))
571 and then not Needs_Finalization (Typ)
573 (not Has_Non_Null_Base_Init_Proc (Typ)
574 or else Is_Imported (E)))
577 (Present (Expression (Decl))
578 and then Is_Scalar_Type (Typ))
584 (Is_Bit_Packed_Array (Typ)
586 Is_Modular_Integer_Type (Packed_Array_Type (Typ)))
590 -- Otherwise, we require the address clause to be constant because
591 -- the call to the initialization procedure (or the attach code) has
592 -- to happen at the point of the declaration.
593 -- Actually the IP call has been moved to the freeze actions
594 -- anyway, so maybe we can relax this restriction???
597 Check_Constant_Address_Clause (Expr, E);
599 -- Has_Delayed_Freeze was set on E when the address clause was
600 -- analyzed. Reset the flag now unless freeze actions were
601 -- attached to it in the mean time.
603 if No (Freeze_Node (E)) then
604 Set_Has_Delayed_Freeze (E, False);
608 if not Error_Posted (Expr)
609 and then not Needs_Finalization (Typ)
611 Warn_Overlay (Expr, Typ, Name (Addr));
614 end Check_Address_Clause;
616 -----------------------------
617 -- Check_Compile_Time_Size --
618 -----------------------------
620 procedure Check_Compile_Time_Size (T : Entity_Id) is
622 procedure Set_Small_Size (T : Entity_Id; S : Uint);
623 -- Sets the compile time known size (32 bits or less) in the Esize
624 -- field, of T checking for a size clause that was given which attempts
625 -- to give a smaller size, and also checking for an alignment clause.
627 function Size_Known (T : Entity_Id) return Boolean;
628 -- Recursive function that does all the work
630 function Static_Discriminated_Components (T : Entity_Id) return Boolean;
631 -- If T is a constrained subtype, its size is not known if any of its
632 -- discriminant constraints is not static and it is not a null record.
633 -- The test is conservative and doesn't check that the components are
634 -- in fact constrained by non-static discriminant values. Could be made
641 procedure Set_Small_Size (T : Entity_Id; S : Uint) is
646 -- Don't bother if alignment clause with a value other than 1 is
647 -- present, because size may be padded up to meet back end alignment
648 -- requirements, and only the back end knows the rules!
650 elsif Known_Alignment (T) and then Alignment (T) /= 1 then
653 -- Check for bad size clause given
655 elsif Has_Size_Clause (T) then
656 if RM_Size (T) < S then
657 Error_Msg_Uint_1 := S;
659 ("size for& too small, minimum allowed is ^",
662 elsif Unknown_Esize (T) then
666 -- Set sizes if not set already
669 if Unknown_Esize (T) then
673 if Unknown_RM_Size (T) then
683 function Size_Known (T : Entity_Id) return Boolean is
691 if Size_Known_At_Compile_Time (T) then
694 -- Always True for scalar types. This is true even for generic formal
695 -- scalar types. We used to return False in the latter case, but the
696 -- size is known at compile time, even in the template, we just do
697 -- not know the exact size but that's not the point of this routine.
699 elsif Is_Scalar_Type (T)
700 or else Is_Task_Type (T)
706 elsif Is_Array_Type (T) then
708 -- String literals always have known size, and we can set it
710 if Ekind (T) = E_String_Literal_Subtype then
711 Set_Small_Size (T, Component_Size (T)
712 * String_Literal_Length (T));
715 -- Unconstrained types never have known at compile time size
717 elsif not Is_Constrained (T) then
720 -- Don't do any recursion on type with error posted, since we may
721 -- have a malformed type that leads us into a loop.
723 elsif Error_Posted (T) then
726 -- Otherwise if component size unknown, then array size unknown
728 elsif not Size_Known (Component_Type (T)) then
732 -- Check for all indexes static, and also compute possible size
733 -- (in case it is less than 32 and may be packable).
736 Esiz : Uint := Component_Size (T);
740 Index := First_Index (T);
741 while Present (Index) loop
742 if Nkind (Index) = N_Range then
743 Get_Index_Bounds (Index, Low, High);
745 elsif Error_Posted (Scalar_Range (Etype (Index))) then
749 Low := Type_Low_Bound (Etype (Index));
750 High := Type_High_Bound (Etype (Index));
753 if not Compile_Time_Known_Value (Low)
754 or else not Compile_Time_Known_Value (High)
755 or else Etype (Index) = Any_Type
760 Dim := Expr_Value (High) - Expr_Value (Low) + 1;
772 Set_Small_Size (T, Esiz);
776 -- Access types always have known at compile time sizes
778 elsif Is_Access_Type (T) then
781 -- For non-generic private types, go to underlying type if present
783 elsif Is_Private_Type (T)
784 and then not Is_Generic_Type (T)
785 and then Present (Underlying_Type (T))
787 -- Don't do any recursion on type with error posted, since we may
788 -- have a malformed type that leads us into a loop.
790 if Error_Posted (T) then
793 return Size_Known (Underlying_Type (T));
798 elsif Is_Record_Type (T) then
800 -- A class-wide type is never considered to have a known size
802 if Is_Class_Wide_Type (T) then
805 -- A subtype of a variant record must not have non-static
806 -- discriminanted components.
808 elsif T /= Base_Type (T)
809 and then not Static_Discriminated_Components (T)
813 -- Don't do any recursion on type with error posted, since we may
814 -- have a malformed type that leads us into a loop.
816 elsif Error_Posted (T) then
820 -- Now look at the components of the record
823 -- The following two variables are used to keep track of the
824 -- size of packed records if we can tell the size of the packed
825 -- record in the front end. Packed_Size_Known is True if so far
826 -- we can figure out the size. It is initialized to True for a
827 -- packed record, unless the record has discriminants. The
828 -- reason we eliminate the discriminated case is that we don't
829 -- know the way the back end lays out discriminated packed
830 -- records. If Packed_Size_Known is True, then Packed_Size is
831 -- the size in bits so far.
833 Packed_Size_Known : Boolean :=
835 and then not Has_Discriminants (T);
837 Packed_Size : Uint := Uint_0;
840 -- Test for variant part present
842 if Has_Discriminants (T)
843 and then Present (Parent (T))
844 and then Nkind (Parent (T)) = N_Full_Type_Declaration
845 and then Nkind (Type_Definition (Parent (T))) =
847 and then not Null_Present (Type_Definition (Parent (T)))
848 and then Present (Variant_Part
849 (Component_List (Type_Definition (Parent (T)))))
851 -- If variant part is present, and type is unconstrained,
852 -- then we must have defaulted discriminants, or a size
853 -- clause must be present for the type, or else the size
854 -- is definitely not known at compile time.
856 if not Is_Constrained (T)
858 No (Discriminant_Default_Value
859 (First_Discriminant (T)))
860 and then Unknown_Esize (T)
866 -- Loop through components
868 Comp := First_Component_Or_Discriminant (T);
869 while Present (Comp) loop
870 Ctyp := Etype (Comp);
872 -- We do not know the packed size if there is a component
873 -- clause present (we possibly could, but this would only
874 -- help in the case of a record with partial rep clauses.
875 -- That's because in the case of full rep clauses, the
876 -- size gets figured out anyway by a different circuit).
878 if Present (Component_Clause (Comp)) then
879 Packed_Size_Known := False;
882 -- We need to identify a component that is an array where
883 -- the index type is an enumeration type with non-standard
884 -- representation, and some bound of the type depends on a
887 -- This is because gigi computes the size by doing a
888 -- substitution of the appropriate discriminant value in
889 -- the size expression for the base type, and gigi is not
890 -- clever enough to evaluate the resulting expression (which
891 -- involves a call to rep_to_pos) at compile time.
893 -- It would be nice if gigi would either recognize that
894 -- this expression can be computed at compile time, or
895 -- alternatively figured out the size from the subtype
896 -- directly, where all the information is at hand ???
898 if Is_Array_Type (Etype (Comp))
899 and then Present (Packed_Array_Type (Etype (Comp)))
902 Ocomp : constant Entity_Id :=
903 Original_Record_Component (Comp);
904 OCtyp : constant Entity_Id := Etype (Ocomp);
910 Ind := First_Index (OCtyp);
911 while Present (Ind) loop
912 Indtyp := Etype (Ind);
914 if Is_Enumeration_Type (Indtyp)
915 and then Has_Non_Standard_Rep (Indtyp)
917 Lo := Type_Low_Bound (Indtyp);
918 Hi := Type_High_Bound (Indtyp);
920 if Is_Entity_Name (Lo)
921 and then Ekind (Entity (Lo)) = E_Discriminant
925 elsif Is_Entity_Name (Hi)
926 and then Ekind (Entity (Hi)) = E_Discriminant
937 -- Clearly size of record is not known if the size of one of
938 -- the components is not known.
940 if not Size_Known (Ctyp) then
944 -- Accumulate packed size if possible
946 if Packed_Size_Known then
948 -- We can only deal with elementary types, since for
949 -- non-elementary components, alignment enters into the
950 -- picture, and we don't know enough to handle proper
951 -- alignment in this context. Packed arrays count as
952 -- elementary if the representation is a modular type.
954 if Is_Elementary_Type (Ctyp)
955 or else (Is_Array_Type (Ctyp)
956 and then Present (Packed_Array_Type (Ctyp))
957 and then Is_Modular_Integer_Type
958 (Packed_Array_Type (Ctyp)))
960 -- If RM_Size is known and static, then we can keep
961 -- accumulating the packed size.
963 if Known_Static_RM_Size (Ctyp) then
965 -- A little glitch, to be removed sometime ???
966 -- gigi does not understand zero sizes yet.
968 if RM_Size (Ctyp) = Uint_0 then
969 Packed_Size_Known := False;
971 -- Normal case where we can keep accumulating the
972 -- packed array size.
975 Packed_Size := Packed_Size + RM_Size (Ctyp);
978 -- If we have a field whose RM_Size is not known then
979 -- we can't figure out the packed size here.
982 Packed_Size_Known := False;
985 -- If we have a non-elementary type we can't figure out
986 -- the packed array size (alignment issues).
989 Packed_Size_Known := False;
993 Next_Component_Or_Discriminant (Comp);
996 if Packed_Size_Known then
997 Set_Small_Size (T, Packed_Size);
1003 -- All other cases, size not known at compile time
1010 -------------------------------------
1011 -- Static_Discriminated_Components --
1012 -------------------------------------
1014 function Static_Discriminated_Components
1015 (T : Entity_Id) return Boolean
1017 Constraint : Elmt_Id;
1020 if Has_Discriminants (T)
1021 and then Present (Discriminant_Constraint (T))
1022 and then Present (First_Component (T))
1024 Constraint := First_Elmt (Discriminant_Constraint (T));
1025 while Present (Constraint) loop
1026 if not Compile_Time_Known_Value (Node (Constraint)) then
1030 Next_Elmt (Constraint);
1035 end Static_Discriminated_Components;
1037 -- Start of processing for Check_Compile_Time_Size
1040 Set_Size_Known_At_Compile_Time (T, Size_Known (T));
1041 end Check_Compile_Time_Size;
1043 -----------------------------
1044 -- Check_Debug_Info_Needed --
1045 -----------------------------
1047 procedure Check_Debug_Info_Needed (T : Entity_Id) is
1049 if Debug_Info_Off (T) then
1052 elsif Comes_From_Source (T)
1053 or else Debug_Generated_Code
1054 or else Debug_Flag_VV
1055 or else Needs_Debug_Info (T)
1057 Set_Debug_Info_Needed (T);
1059 end Check_Debug_Info_Needed;
1061 ----------------------------
1062 -- Check_Strict_Alignment --
1063 ----------------------------
1065 procedure Check_Strict_Alignment (E : Entity_Id) is
1069 if Is_Tagged_Type (E) or else Is_Concurrent_Type (E) then
1070 Set_Strict_Alignment (E);
1072 elsif Is_Array_Type (E) then
1073 Set_Strict_Alignment (E, Strict_Alignment (Component_Type (E)));
1075 elsif Is_Record_Type (E) then
1076 if Is_Limited_Record (E) then
1077 Set_Strict_Alignment (E);
1081 Comp := First_Component (E);
1083 while Present (Comp) loop
1084 if not Is_Type (Comp)
1085 and then (Strict_Alignment (Etype (Comp))
1086 or else Is_Aliased (Comp))
1088 Set_Strict_Alignment (E);
1092 Next_Component (Comp);
1095 end Check_Strict_Alignment;
1097 -------------------------
1098 -- Check_Unsigned_Type --
1099 -------------------------
1101 procedure Check_Unsigned_Type (E : Entity_Id) is
1102 Ancestor : Entity_Id;
1107 if not Is_Discrete_Or_Fixed_Point_Type (E) then
1111 -- Do not attempt to analyze case where range was in error
1113 if Error_Posted (Scalar_Range (E)) then
1117 -- The situation that is non trivial is something like
1119 -- subtype x1 is integer range -10 .. +10;
1120 -- subtype x2 is x1 range 0 .. V1;
1121 -- subtype x3 is x2 range V2 .. V3;
1122 -- subtype x4 is x3 range V4 .. V5;
1124 -- where Vn are variables. Here the base type is signed, but we still
1125 -- know that x4 is unsigned because of the lower bound of x2.
1127 -- The only way to deal with this is to look up the ancestor chain
1131 if Ancestor = Any_Type or else Etype (Ancestor) = Any_Type then
1135 Lo_Bound := Type_Low_Bound (Ancestor);
1137 if Compile_Time_Known_Value (Lo_Bound) then
1139 if Expr_Rep_Value (Lo_Bound) >= 0 then
1140 Set_Is_Unsigned_Type (E, True);
1146 Ancestor := Ancestor_Subtype (Ancestor);
1148 -- If no ancestor had a static lower bound, go to base type
1150 if No (Ancestor) then
1152 -- Note: the reason we still check for a compile time known
1153 -- value for the base type is that at least in the case of
1154 -- generic formals, we can have bounds that fail this test,
1155 -- and there may be other cases in error situations.
1157 Btyp := Base_Type (E);
1159 if Btyp = Any_Type or else Etype (Btyp) = Any_Type then
1163 Lo_Bound := Type_Low_Bound (Base_Type (E));
1165 if Compile_Time_Known_Value (Lo_Bound)
1166 and then Expr_Rep_Value (Lo_Bound) >= 0
1168 Set_Is_Unsigned_Type (E, True);
1175 end Check_Unsigned_Type;
1177 -------------------------
1178 -- Is_Atomic_Aggregate --
1179 -------------------------
1181 function Is_Atomic_Aggregate
1183 Typ : Entity_Id) return Boolean
1185 Loc : constant Source_Ptr := Sloc (E);
1193 -- Array may be qualified, so find outer context
1195 if Nkind (Par) = N_Qualified_Expression then
1196 Par := Parent (Par);
1199 if Nkind_In (Par, N_Object_Declaration, N_Assignment_Statement)
1200 and then Comes_From_Source (Par)
1202 Temp := Make_Temporary (Loc, 'T', E);
1204 Make_Object_Declaration (Loc,
1205 Defining_Identifier => Temp,
1206 Object_Definition => New_Occurrence_Of (Typ, Loc),
1207 Expression => Relocate_Node (E));
1208 Insert_Before (Par, New_N);
1211 Set_Expression (Par, New_Occurrence_Of (Temp, Loc));
1217 end Is_Atomic_Aggregate;
1223 -- Note: the easy coding for this procedure would be to just build a
1224 -- single list of freeze nodes and then insert them and analyze them
1225 -- all at once. This won't work, because the analysis of earlier freeze
1226 -- nodes may recursively freeze types which would otherwise appear later
1227 -- on in the freeze list. So we must analyze and expand the freeze nodes
1228 -- as they are generated.
1230 procedure Freeze_All (From : Entity_Id; After : in out Node_Id) is
1231 Loc : constant Source_Ptr := Sloc (After);
1235 procedure Freeze_All_Ent (From : Entity_Id; After : in out Node_Id);
1236 -- This is the internal recursive routine that does freezing of entities
1237 -- (but NOT the analysis of default expressions, which should not be
1238 -- recursive, we don't want to analyze those till we are sure that ALL
1239 -- the types are frozen).
1241 --------------------
1242 -- Freeze_All_Ent --
1243 --------------------
1245 procedure Freeze_All_Ent
1247 After : in out Node_Id)
1253 procedure Process_Flist;
1254 -- If freeze nodes are present, insert and analyze, and reset cursor
1255 -- for next insertion.
1261 procedure Process_Flist is
1263 if Is_Non_Empty_List (Flist) then
1264 Lastn := Next (After);
1265 Insert_List_After_And_Analyze (After, Flist);
1267 if Present (Lastn) then
1268 After := Prev (Lastn);
1270 After := Last (List_Containing (After));
1275 -- Start or processing for Freeze_All_Ent
1279 while Present (E) loop
1281 -- If the entity is an inner package which is not a package
1282 -- renaming, then its entities must be frozen at this point. Note
1283 -- that such entities do NOT get frozen at the end of the nested
1284 -- package itself (only library packages freeze).
1286 -- Same is true for task declarations, where anonymous records
1287 -- created for entry parameters must be frozen.
1289 if Ekind (E) = E_Package
1290 and then No (Renamed_Object (E))
1291 and then not Is_Child_Unit (E)
1292 and then not Is_Frozen (E)
1295 Install_Visible_Declarations (E);
1296 Install_Private_Declarations (E);
1298 Freeze_All (First_Entity (E), After);
1300 End_Package_Scope (E);
1302 elsif Ekind (E) in Task_Kind
1304 (Nkind (Parent (E)) = N_Task_Type_Declaration
1306 Nkind (Parent (E)) = N_Single_Task_Declaration)
1309 Freeze_All (First_Entity (E), After);
1312 -- For a derived tagged type, we must ensure that all the
1313 -- primitive operations of the parent have been frozen, so that
1314 -- their addresses will be in the parent's dispatch table at the
1315 -- point it is inherited.
1317 elsif Ekind (E) = E_Record_Type
1318 and then Is_Tagged_Type (E)
1319 and then Is_Tagged_Type (Etype (E))
1320 and then Is_Derived_Type (E)
1323 Prim_List : constant Elist_Id :=
1324 Primitive_Operations (Etype (E));
1330 Prim := First_Elmt (Prim_List);
1332 while Present (Prim) loop
1333 Subp := Node (Prim);
1335 if Comes_From_Source (Subp)
1336 and then not Is_Frozen (Subp)
1338 Flist := Freeze_Entity (Subp, Loc);
1347 if not Is_Frozen (E) then
1348 Flist := Freeze_Entity (E, Loc);
1352 -- If an incomplete type is still not frozen, this may be a
1353 -- premature freezing because of a body declaration that follows.
1354 -- Indicate where the freezing took place.
1356 -- If the freezing is caused by the end of the current declarative
1357 -- part, it is a Taft Amendment type, and there is no error.
1359 if not Is_Frozen (E)
1360 and then Ekind (E) = E_Incomplete_Type
1363 Bod : constant Node_Id := Next (After);
1366 if (Nkind (Bod) = N_Subprogram_Body
1367 or else Nkind (Bod) = N_Entry_Body
1368 or else Nkind (Bod) = N_Package_Body
1369 or else Nkind (Bod) = N_Protected_Body
1370 or else Nkind (Bod) = N_Task_Body
1371 or else Nkind (Bod) in N_Body_Stub)
1373 List_Containing (After) = List_Containing (Parent (E))
1375 Error_Msg_Sloc := Sloc (Next (After));
1377 ("type& is frozen# before its full declaration",
1387 -- Start of processing for Freeze_All
1390 Freeze_All_Ent (From, After);
1392 -- Now that all types are frozen, we can deal with default expressions
1393 -- that require us to build a default expression functions. This is the
1394 -- point at which such functions are constructed (after all types that
1395 -- might be used in such expressions have been frozen).
1397 -- For subprograms that are renaming_as_body, we create the wrapper
1398 -- bodies as needed.
1400 -- We also add finalization chains to access types whose designated
1401 -- types are controlled. This is normally done when freezing the type,
1402 -- but this misses recursive type definitions where the later members
1403 -- of the recursion introduce controlled components.
1405 -- Loop through entities
1408 while Present (E) loop
1409 if Is_Subprogram (E) then
1411 if not Default_Expressions_Processed (E) then
1412 Process_Default_Expressions (E, After);
1415 if not Has_Completion (E) then
1416 Decl := Unit_Declaration_Node (E);
1418 if Nkind (Decl) = N_Subprogram_Renaming_Declaration then
1419 Build_And_Analyze_Renamed_Body (Decl, E, After);
1421 elsif Nkind (Decl) = N_Subprogram_Declaration
1422 and then Present (Corresponding_Body (Decl))
1424 Nkind (Unit_Declaration_Node (Corresponding_Body (Decl)))
1425 = N_Subprogram_Renaming_Declaration
1427 Build_And_Analyze_Renamed_Body
1428 (Decl, Corresponding_Body (Decl), After);
1432 elsif Ekind (E) in Task_Kind
1434 (Nkind (Parent (E)) = N_Task_Type_Declaration
1436 Nkind (Parent (E)) = N_Single_Task_Declaration)
1441 Ent := First_Entity (E);
1443 while Present (Ent) loop
1446 and then not Default_Expressions_Processed (Ent)
1448 Process_Default_Expressions (Ent, After);
1455 elsif Is_Access_Type (E)
1456 and then Comes_From_Source (E)
1457 and then Ekind (Directly_Designated_Type (E)) = E_Incomplete_Type
1458 and then Needs_Finalization (Designated_Type (E))
1459 and then No (Associated_Final_Chain (E))
1461 Build_Final_List (Parent (E), E);
1468 -----------------------
1469 -- Freeze_And_Append --
1470 -----------------------
1472 procedure Freeze_And_Append
1475 Result : in out List_Id)
1477 L : constant List_Id := Freeze_Entity (Ent, Loc);
1479 if Is_Non_Empty_List (L) then
1480 if Result = No_List then
1483 Append_List (L, Result);
1486 end Freeze_And_Append;
1492 procedure Freeze_Before (N : Node_Id; T : Entity_Id) is
1493 Freeze_Nodes : constant List_Id := Freeze_Entity (T, Sloc (N));
1495 if Is_Non_Empty_List (Freeze_Nodes) then
1496 Insert_Actions (N, Freeze_Nodes);
1504 function Freeze_Entity (E : Entity_Id; Loc : Source_Ptr) return List_Id is
1505 Test_E : Entity_Id := E;
1513 Has_Default_Initialization : Boolean := False;
1514 -- This flag gets set to true for a variable with default initialization
1516 procedure Check_Current_Instance (Comp_Decl : Node_Id);
1517 -- Check that an Access or Unchecked_Access attribute with a prefix
1518 -- which is the current instance type can only be applied when the type
1521 procedure Check_Suspicious_Modulus (Utype : Entity_Id);
1522 -- Give warning for modulus of 8, 16, 32, or 64 given as an explicit
1523 -- integer literal without an explicit corresponding size clause. The
1524 -- caller has checked that Utype is a modular integer type.
1526 function After_Last_Declaration return Boolean;
1527 -- If Loc is a freeze_entity that appears after the last declaration
1528 -- in the scope, inhibit error messages on late completion.
1530 procedure Freeze_Record_Type (Rec : Entity_Id);
1531 -- Freeze each component, handle some representation clauses, and freeze
1532 -- primitive operations if this is a tagged type.
1534 ----------------------------
1535 -- After_Last_Declaration --
1536 ----------------------------
1538 function After_Last_Declaration return Boolean is
1539 Spec : constant Node_Id := Parent (Current_Scope);
1541 if Nkind (Spec) = N_Package_Specification then
1542 if Present (Private_Declarations (Spec)) then
1543 return Loc >= Sloc (Last (Private_Declarations (Spec)));
1544 elsif Present (Visible_Declarations (Spec)) then
1545 return Loc >= Sloc (Last (Visible_Declarations (Spec)));
1552 end After_Last_Declaration;
1554 ----------------------------
1555 -- Check_Current_Instance --
1556 ----------------------------
1558 procedure Check_Current_Instance (Comp_Decl : Node_Id) is
1560 Rec_Type : constant Entity_Id :=
1561 Scope (Defining_Identifier (Comp_Decl));
1563 Decl : constant Node_Id := Parent (Rec_Type);
1565 function Process (N : Node_Id) return Traverse_Result;
1566 -- Process routine to apply check to given node
1572 function Process (N : Node_Id) return Traverse_Result is
1575 when N_Attribute_Reference =>
1576 if (Attribute_Name (N) = Name_Access
1578 Attribute_Name (N) = Name_Unchecked_Access)
1579 and then Is_Entity_Name (Prefix (N))
1580 and then Is_Type (Entity (Prefix (N)))
1581 and then Entity (Prefix (N)) = E
1584 ("current instance must be a limited type", Prefix (N));
1590 when others => return OK;
1594 procedure Traverse is new Traverse_Proc (Process);
1596 -- Start of processing for Check_Current_Instance
1599 -- In Ada95, the (imprecise) rule is that the current instance of a
1600 -- limited type is aliased. In Ada2005, limitedness must be explicit:
1601 -- either a tagged type, or a limited record.
1603 if Is_Limited_Type (Rec_Type)
1604 and then (Ada_Version < Ada_05 or else Is_Tagged_Type (Rec_Type))
1608 elsif Nkind (Decl) = N_Full_Type_Declaration
1609 and then Limited_Present (Type_Definition (Decl))
1614 Traverse (Comp_Decl);
1616 end Check_Current_Instance;
1618 ------------------------------
1619 -- Check_Suspicious_Modulus --
1620 ------------------------------
1622 procedure Check_Suspicious_Modulus (Utype : Entity_Id) is
1623 Decl : constant Node_Id := Declaration_Node (Underlying_Type (Utype));
1626 if Nkind (Decl) = N_Full_Type_Declaration then
1628 Tdef : constant Node_Id := Type_Definition (Decl);
1630 if Nkind (Tdef) = N_Modular_Type_Definition then
1632 Modulus : constant Node_Id :=
1633 Original_Node (Expression (Tdef));
1635 if Nkind (Modulus) = N_Integer_Literal then
1637 Modv : constant Uint := Intval (Modulus);
1638 Sizv : constant Uint := RM_Size (Utype);
1641 -- First case, modulus and size are the same. This
1642 -- happens if you have something like mod 32, with
1643 -- an explicit size of 32, this is for sure a case
1644 -- where the warning is given, since it is seems
1645 -- very unlikely that someone would want e.g. a
1646 -- five bit type stored in 32 bits. It is much
1647 -- more likely they wanted a 32-bit type.
1652 -- Second case, the modulus is 32 or 64 and no
1653 -- size clause is present. This is a less clear
1654 -- case for giving the warning, but in the case
1655 -- of 32/64 (5-bit or 6-bit types) these seem rare
1656 -- enough that it is a likely error (and in any
1657 -- case using 2**5 or 2**6 in these cases seems
1658 -- clearer. We don't include 8 or 16 here, simply
1659 -- because in practice 3-bit and 4-bit types are
1660 -- more common and too many false positives if
1661 -- we warn in these cases.
1663 elsif not Has_Size_Clause (Utype)
1664 and then (Modv = Uint_32 or else Modv = Uint_64)
1668 -- No warning needed
1674 -- If we fall through, give warning
1676 Error_Msg_Uint_1 := Modv;
1678 ("?2 '*'*^' may have been intended here",
1686 end Check_Suspicious_Modulus;
1688 ------------------------
1689 -- Freeze_Record_Type --
1690 ------------------------
1692 procedure Freeze_Record_Type (Rec : Entity_Id) is
1699 pragma Warnings (Off, Junk);
1701 Unplaced_Component : Boolean := False;
1702 -- Set True if we find at least one component with no component
1703 -- clause (used to warn about useless Pack pragmas).
1705 Placed_Component : Boolean := False;
1706 -- Set True if we find at least one component with a component
1707 -- clause (used to warn about useless Bit_Order pragmas, and also
1708 -- to detect cases where Implicit_Packing may have an effect).
1710 All_Scalar_Components : Boolean := True;
1711 -- Set False if we encounter a component of a non-scalar type
1713 Scalar_Component_Total_RM_Size : Uint := Uint_0;
1714 Scalar_Component_Total_Esize : Uint := Uint_0;
1715 -- Accumulates total RM_Size values and total Esize values of all
1716 -- scalar components. Used for processing of Implicit_Packing.
1718 function Check_Allocator (N : Node_Id) return Node_Id;
1719 -- If N is an allocator, possibly wrapped in one or more level of
1720 -- qualified expression(s), return the inner allocator node, else
1723 procedure Check_Itype (Typ : Entity_Id);
1724 -- If the component subtype is an access to a constrained subtype of
1725 -- an already frozen type, make the subtype frozen as well. It might
1726 -- otherwise be frozen in the wrong scope, and a freeze node on
1727 -- subtype has no effect. Similarly, if the component subtype is a
1728 -- regular (not protected) access to subprogram, set the anonymous
1729 -- subprogram type to frozen as well, to prevent an out-of-scope
1730 -- freeze node at some eventual point of call. Protected operations
1731 -- are handled elsewhere.
1733 ---------------------
1734 -- Check_Allocator --
1735 ---------------------
1737 function Check_Allocator (N : Node_Id) return Node_Id is
1742 if Nkind (Inner) = N_Allocator then
1744 elsif Nkind (Inner) = N_Qualified_Expression then
1745 Inner := Expression (Inner);
1750 end Check_Allocator;
1756 procedure Check_Itype (Typ : Entity_Id) is
1757 Desig : constant Entity_Id := Designated_Type (Typ);
1760 if not Is_Frozen (Desig)
1761 and then Is_Frozen (Base_Type (Desig))
1763 Set_Is_Frozen (Desig);
1765 -- In addition, add an Itype_Reference to ensure that the
1766 -- access subtype is elaborated early enough. This cannot be
1767 -- done if the subtype may depend on discriminants.
1769 if Ekind (Comp) = E_Component
1770 and then Is_Itype (Etype (Comp))
1771 and then not Has_Discriminants (Rec)
1773 IR := Make_Itype_Reference (Sloc (Comp));
1774 Set_Itype (IR, Desig);
1777 Result := New_List (IR);
1779 Append (IR, Result);
1783 elsif Ekind (Typ) = E_Anonymous_Access_Subprogram_Type
1784 and then Convention (Desig) /= Convention_Protected
1786 Set_Is_Frozen (Desig);
1790 -- Start of processing for Freeze_Record_Type
1793 -- If this is a subtype of a controlled type, declared without a
1794 -- constraint, the _controller may not appear in the component list
1795 -- if the parent was not frozen at the point of subtype declaration.
1796 -- Inherit the _controller component now.
1798 if Rec /= Base_Type (Rec)
1799 and then Has_Controlled_Component (Rec)
1801 if Nkind (Parent (Rec)) = N_Subtype_Declaration
1802 and then Is_Entity_Name (Subtype_Indication (Parent (Rec)))
1804 Set_First_Entity (Rec, First_Entity (Base_Type (Rec)));
1806 -- If this is an internal type without a declaration, as for
1807 -- record component, the base type may not yet be frozen, and its
1808 -- controller has not been created. Add an explicit freeze node
1809 -- for the itype, so it will be frozen after the base type. This
1810 -- freeze node is used to communicate with the expander, in order
1811 -- to create the controller for the enclosing record, and it is
1812 -- deleted afterwards (see exp_ch3). It must not be created when
1813 -- expansion is off, because it might appear in the wrong context
1814 -- for the back end.
1816 elsif Is_Itype (Rec)
1817 and then Has_Delayed_Freeze (Base_Type (Rec))
1819 Nkind (Associated_Node_For_Itype (Rec)) =
1820 N_Component_Declaration
1821 and then Expander_Active
1823 Ensure_Freeze_Node (Rec);
1827 -- Freeze components and embedded subtypes
1829 Comp := First_Entity (Rec);
1831 while Present (Comp) loop
1833 -- First handle the component case
1835 if Ekind (Comp) = E_Component
1836 or else Ekind (Comp) = E_Discriminant
1839 CC : constant Node_Id := Component_Clause (Comp);
1842 -- Freezing a record type freezes the type of each of its
1843 -- components. However, if the type of the component is
1844 -- part of this record, we do not want or need a separate
1845 -- Freeze_Node. Note that Is_Itype is wrong because that's
1846 -- also set in private type cases. We also can't check for
1847 -- the Scope being exactly Rec because of private types and
1848 -- record extensions.
1850 if Is_Itype (Etype (Comp))
1851 and then Is_Record_Type (Underlying_Type
1852 (Scope (Etype (Comp))))
1854 Undelay_Type (Etype (Comp));
1857 Freeze_And_Append (Etype (Comp), Loc, Result);
1859 -- Check for error of component clause given for variable
1860 -- sized type. We have to delay this test till this point,
1861 -- since the component type has to be frozen for us to know
1862 -- if it is variable length. We omit this test in a generic
1863 -- context, it will be applied at instantiation time.
1865 if Present (CC) then
1866 Placed_Component := True;
1868 if Inside_A_Generic then
1872 Size_Known_At_Compile_Time
1873 (Underlying_Type (Etype (Comp)))
1876 ("component clause not allowed for variable " &
1877 "length component", CC);
1881 Unplaced_Component := True;
1884 -- Case of component requires byte alignment
1886 if Must_Be_On_Byte_Boundary (Etype (Comp)) then
1888 -- Set the enclosing record to also require byte align
1890 Set_Must_Be_On_Byte_Boundary (Rec);
1892 -- Check for component clause that is inconsistent with
1893 -- the required byte boundary alignment.
1896 and then Normalized_First_Bit (Comp) mod
1897 System_Storage_Unit /= 0
1900 ("component & must be byte aligned",
1901 Component_Name (Component_Clause (Comp)));
1907 -- Gather data for possible Implicit_Packing later. Note that at
1908 -- this stage we might be dealing with a real component, or with
1909 -- an implicit subtype declaration.
1911 if not Is_Scalar_Type (Etype (Comp)) then
1912 All_Scalar_Components := False;
1914 Scalar_Component_Total_RM_Size :=
1915 Scalar_Component_Total_RM_Size + RM_Size (Etype (Comp));
1916 Scalar_Component_Total_Esize :=
1917 Scalar_Component_Total_Esize + Esize (Etype (Comp));
1920 -- If the component is an Itype with Delayed_Freeze and is either
1921 -- a record or array subtype and its base type has not yet been
1922 -- frozen, we must remove this from the entity list of this
1923 -- record and put it on the entity list of the scope of its base
1924 -- type. Note that we know that this is not the type of a
1925 -- component since we cleared Has_Delayed_Freeze for it in the
1926 -- previous loop. Thus this must be the Designated_Type of an
1927 -- access type, which is the type of a component.
1930 and then Is_Type (Scope (Comp))
1931 and then Is_Composite_Type (Comp)
1932 and then Base_Type (Comp) /= Comp
1933 and then Has_Delayed_Freeze (Comp)
1934 and then not Is_Frozen (Base_Type (Comp))
1937 Will_Be_Frozen : Boolean := False;
1941 -- We have a pretty bad kludge here. Suppose Rec is subtype
1942 -- being defined in a subprogram that's created as part of
1943 -- the freezing of Rec'Base. In that case, we know that
1944 -- Comp'Base must have already been frozen by the time we
1945 -- get to elaborate this because Gigi doesn't elaborate any
1946 -- bodies until it has elaborated all of the declarative
1947 -- part. But Is_Frozen will not be set at this point because
1948 -- we are processing code in lexical order.
1950 -- We detect this case by going up the Scope chain of Rec
1951 -- and seeing if we have a subprogram scope before reaching
1952 -- the top of the scope chain or that of Comp'Base. If we
1953 -- do, then mark that Comp'Base will actually be frozen. If
1954 -- so, we merely undelay it.
1957 while Present (S) loop
1958 if Is_Subprogram (S) then
1959 Will_Be_Frozen := True;
1961 elsif S = Scope (Base_Type (Comp)) then
1968 if Will_Be_Frozen then
1969 Undelay_Type (Comp);
1971 if Present (Prev) then
1972 Set_Next_Entity (Prev, Next_Entity (Comp));
1974 Set_First_Entity (Rec, Next_Entity (Comp));
1977 -- Insert in entity list of scope of base type (which
1978 -- must be an enclosing scope, because still unfrozen).
1980 Append_Entity (Comp, Scope (Base_Type (Comp)));
1984 -- If the component is an access type with an allocator as default
1985 -- value, the designated type will be frozen by the corresponding
1986 -- expression in init_proc. In order to place the freeze node for
1987 -- the designated type before that for the current record type,
1990 -- Same process if the component is an array of access types,
1991 -- initialized with an aggregate. If the designated type is
1992 -- private, it cannot contain allocators, and it is premature
1993 -- to freeze the type, so we check for this as well.
1995 elsif Is_Access_Type (Etype (Comp))
1996 and then Present (Parent (Comp))
1997 and then Present (Expression (Parent (Comp)))
2000 Alloc : constant Node_Id :=
2001 Check_Allocator (Expression (Parent (Comp)));
2004 if Present (Alloc) then
2006 -- If component is pointer to a classwide type, freeze
2007 -- the specific type in the expression being allocated.
2008 -- The expression may be a subtype indication, in which
2009 -- case freeze the subtype mark.
2011 if Is_Class_Wide_Type
2012 (Designated_Type (Etype (Comp)))
2014 if Is_Entity_Name (Expression (Alloc)) then
2016 (Entity (Expression (Alloc)), Loc, Result);
2018 Nkind (Expression (Alloc)) = N_Subtype_Indication
2021 (Entity (Subtype_Mark (Expression (Alloc))),
2025 elsif Is_Itype (Designated_Type (Etype (Comp))) then
2026 Check_Itype (Etype (Comp));
2030 (Designated_Type (Etype (Comp)), Loc, Result);
2035 elsif Is_Access_Type (Etype (Comp))
2036 and then Is_Itype (Designated_Type (Etype (Comp)))
2038 Check_Itype (Etype (Comp));
2040 elsif Is_Array_Type (Etype (Comp))
2041 and then Is_Access_Type (Component_Type (Etype (Comp)))
2042 and then Present (Parent (Comp))
2043 and then Nkind (Parent (Comp)) = N_Component_Declaration
2044 and then Present (Expression (Parent (Comp)))
2045 and then Nkind (Expression (Parent (Comp))) = N_Aggregate
2046 and then Is_Fully_Defined
2047 (Designated_Type (Component_Type (Etype (Comp))))
2051 (Component_Type (Etype (Comp))), Loc, Result);
2058 -- Deal with pragma Bit_Order setting non-standard bit order
2060 if Reverse_Bit_Order (Rec) and then Base_Type (Rec) = Rec then
2061 if not Placed_Component then
2063 Get_Attribute_Definition_Clause (Rec, Attribute_Bit_Order);
2064 Error_Msg_N ("?Bit_Order specification has no effect", ADC);
2066 ("\?since no component clauses were specified", ADC);
2068 -- Here is where we do the processing for reversed bit order
2071 Adjust_Record_For_Reverse_Bit_Order (Rec);
2075 -- Complete error checking on record representation clause (e.g.
2076 -- overlap of components). This is called after adjusting the
2077 -- record for reverse bit order.
2080 RRC : constant Node_Id := Get_Record_Representation_Clause (Rec);
2082 if Present (RRC) then
2083 Check_Record_Representation_Clause (RRC);
2087 -- Set OK_To_Reorder_Components depending on debug flags
2089 if Rec = Base_Type (Rec)
2090 and then Convention (Rec) = Convention_Ada
2092 if (Has_Discriminants (Rec) and then Debug_Flag_Dot_V)
2094 (not Has_Discriminants (Rec) and then Debug_Flag_Dot_R)
2096 Set_OK_To_Reorder_Components (Rec);
2100 -- Check for useless pragma Pack when all components placed. We only
2101 -- do this check for record types, not subtypes, since a subtype may
2102 -- have all its components placed, and it still makes perfectly good
2103 -- sense to pack other subtypes or the parent type. We do not give
2104 -- this warning if Optimize_Alignment is set to Space, since the
2105 -- pragma Pack does have an effect in this case (it always resets
2106 -- the alignment to one).
2108 if Ekind (Rec) = E_Record_Type
2109 and then Is_Packed (Rec)
2110 and then not Unplaced_Component
2111 and then Optimize_Alignment /= 'S'
2113 -- Reset packed status. Probably not necessary, but we do it so
2114 -- that there is no chance of the back end doing something strange
2115 -- with this redundant indication of packing.
2117 Set_Is_Packed (Rec, False);
2119 -- Give warning if redundant constructs warnings on
2121 if Warn_On_Redundant_Constructs then
2122 Error_Msg_N -- CODEFIX
2123 ("?pragma Pack has no effect, no unplaced components",
2124 Get_Rep_Pragma (Rec, Name_Pack));
2128 -- If this is the record corresponding to a remote type, freeze the
2129 -- remote type here since that is what we are semantically freezing.
2130 -- This prevents the freeze node for that type in an inner scope.
2132 -- Also, Check for controlled components and unchecked unions.
2133 -- Finally, enforce the restriction that access attributes with a
2134 -- current instance prefix can only apply to limited types.
2136 if Ekind (Rec) = E_Record_Type then
2137 if Present (Corresponding_Remote_Type (Rec)) then
2139 (Corresponding_Remote_Type (Rec), Loc, Result);
2142 Comp := First_Component (Rec);
2143 while Present (Comp) loop
2145 -- Do not set Has_Controlled_Component on a class-wide
2146 -- equivalent type. See Make_CW_Equivalent_Type.
2148 if not Is_Class_Wide_Equivalent_Type (Rec)
2149 and then (Has_Controlled_Component (Etype (Comp))
2150 or else (Chars (Comp) /= Name_uParent
2151 and then Is_Controlled (Etype (Comp)))
2152 or else (Is_Protected_Type (Etype (Comp))
2154 (Corresponding_Record_Type
2156 and then Has_Controlled_Component
2157 (Corresponding_Record_Type
2160 Set_Has_Controlled_Component (Rec);
2164 if Has_Unchecked_Union (Etype (Comp)) then
2165 Set_Has_Unchecked_Union (Rec);
2168 if Has_Per_Object_Constraint (Comp) then
2170 -- Scan component declaration for likely misuses of current
2171 -- instance, either in a constraint or a default expression.
2173 Check_Current_Instance (Parent (Comp));
2176 Next_Component (Comp);
2180 Set_Component_Alignment_If_Not_Set (Rec);
2182 -- For first subtypes, check if there are any fixed-point fields with
2183 -- component clauses, where we must check the size. This is not done
2184 -- till the freeze point, since for fixed-point types, we do not know
2185 -- the size until the type is frozen. Similar processing applies to
2186 -- bit packed arrays.
2188 if Is_First_Subtype (Rec) then
2189 Comp := First_Component (Rec);
2191 while Present (Comp) loop
2192 if Present (Component_Clause (Comp))
2193 and then (Is_Fixed_Point_Type (Etype (Comp))
2195 Is_Bit_Packed_Array (Etype (Comp)))
2198 (Component_Name (Component_Clause (Comp)),
2204 Next_Component (Comp);
2208 -- Generate warning for applying C or C++ convention to a record
2209 -- with discriminants. This is suppressed for the unchecked union
2210 -- case, since the whole point in this case is interface C. We also
2211 -- do not generate this within instantiations, since we will have
2212 -- generated a message on the template.
2214 if Has_Discriminants (E)
2215 and then not Is_Unchecked_Union (E)
2216 and then (Convention (E) = Convention_C
2218 Convention (E) = Convention_CPP)
2219 and then Comes_From_Source (E)
2220 and then not In_Instance
2221 and then not Has_Warnings_Off (E)
2222 and then not Has_Warnings_Off (Base_Type (E))
2225 Cprag : constant Node_Id := Get_Rep_Pragma (E, Name_Convention);
2229 if Present (Cprag) then
2230 A2 := Next (First (Pragma_Argument_Associations (Cprag)));
2232 if Convention (E) = Convention_C then
2234 ("?variant record has no direct equivalent in C", A2);
2237 ("?variant record has no direct equivalent in C++", A2);
2241 ("\?use of convention for type& is dubious", A2, E);
2246 -- See if Size is too small as is (and implicit packing might help)
2248 if not Is_Packed (Rec)
2250 -- No implicit packing if even one component is explicitly placed
2252 and then not Placed_Component
2254 -- Must have size clause and all scalar components
2256 and then Has_Size_Clause (Rec)
2257 and then All_Scalar_Components
2259 -- Do not try implicit packing on records with discriminants, too
2260 -- complicated, especially in the variant record case.
2262 and then not Has_Discriminants (Rec)
2264 -- We can implicitly pack if the specified size of the record is
2265 -- less than the sum of the object sizes (no point in packing if
2266 -- this is not the case).
2268 and then Esize (Rec) < Scalar_Component_Total_Esize
2270 -- And the total RM size cannot be greater than the specified size
2271 -- since otherwise packing will not get us where we have to be!
2273 and then Esize (Rec) >= Scalar_Component_Total_RM_Size
2275 -- Never do implicit packing in CodePeer mode since we don't do
2276 -- any packing ever in this mode (why not???)
2278 and then not CodePeer_Mode
2280 -- If implicit packing enabled, do it
2282 if Implicit_Packing then
2283 Set_Is_Packed (Rec);
2285 -- Otherwise flag the size clause
2289 Sz : constant Node_Id := Size_Clause (Rec);
2291 Error_Msg_NE -- CODEFIX
2292 ("size given for& too small", Sz, Rec);
2293 Error_Msg_N -- CODEFIX
2294 ("\use explicit pragma Pack "
2295 & "or use pragma Implicit_Packing", Sz);
2299 end Freeze_Record_Type;
2301 -- Start of processing for Freeze_Entity
2304 -- We are going to test for various reasons why this entity need not be
2305 -- frozen here, but in the case of an Itype that's defined within a
2306 -- record, that test actually applies to the record.
2308 if Is_Itype (E) and then Is_Record_Type (Scope (E)) then
2309 Test_E := Scope (E);
2310 elsif Is_Itype (E) and then Present (Underlying_Type (Scope (E)))
2311 and then Is_Record_Type (Underlying_Type (Scope (E)))
2313 Test_E := Underlying_Type (Scope (E));
2316 -- Do not freeze if already frozen since we only need one freeze node
2318 if Is_Frozen (E) then
2321 -- It is improper to freeze an external entity within a generic because
2322 -- its freeze node will appear in a non-valid context. The entity will
2323 -- be frozen in the proper scope after the current generic is analyzed.
2325 elsif Inside_A_Generic and then External_Ref_In_Generic (Test_E) then
2328 -- Do not freeze a global entity within an inner scope created during
2329 -- expansion. A call to subprogram E within some internal procedure
2330 -- (a stream attribute for example) might require freezing E, but the
2331 -- freeze node must appear in the same declarative part as E itself.
2332 -- The two-pass elaboration mechanism in gigi guarantees that E will
2333 -- be frozen before the inner call is elaborated. We exclude constants
2334 -- from this test, because deferred constants may be frozen early, and
2335 -- must be diagnosed (e.g. in the case of a deferred constant being used
2336 -- in a default expression). If the enclosing subprogram comes from
2337 -- source, or is a generic instance, then the freeze point is the one
2338 -- mandated by the language, and we freeze the entity. A subprogram that
2339 -- is a child unit body that acts as a spec does not have a spec that
2340 -- comes from source, but can only come from source.
2342 elsif In_Open_Scopes (Scope (Test_E))
2343 and then Scope (Test_E) /= Current_Scope
2344 and then Ekind (Test_E) /= E_Constant
2347 S : Entity_Id := Current_Scope;
2350 while Present (S) loop
2351 if Is_Overloadable (S) then
2352 if Comes_From_Source (S)
2353 or else Is_Generic_Instance (S)
2354 or else Is_Child_Unit (S)
2366 -- Similarly, an inlined instance body may make reference to global
2367 -- entities, but these references cannot be the proper freezing point
2368 -- for them, and in the absence of inlining freezing will take place in
2369 -- their own scope. Normally instance bodies are analyzed after the
2370 -- enclosing compilation, and everything has been frozen at the proper
2371 -- place, but with front-end inlining an instance body is compiled
2372 -- before the end of the enclosing scope, and as a result out-of-order
2373 -- freezing must be prevented.
2375 elsif Front_End_Inlining
2376 and then In_Instance_Body
2377 and then Present (Scope (Test_E))
2380 S : Entity_Id := Scope (Test_E);
2383 while Present (S) loop
2384 if Is_Generic_Instance (S) then
2397 -- Here to freeze the entity
2402 -- Case of entity being frozen is other than a type
2404 if not Is_Type (E) then
2406 -- If entity is exported or imported and does not have an external
2407 -- name, now is the time to provide the appropriate default name.
2408 -- Skip this if the entity is stubbed, since we don't need a name
2409 -- for any stubbed routine. For the case on intrinsics, if no
2410 -- external name is specified, then calls will be handled in
2411 -- Exp_Intr.Expand_Intrinsic_Call, and no name is needed; if
2412 -- an external name is provided, then Expand_Intrinsic_Call leaves
2413 -- calls in place for expansion by GIGI.
2415 if (Is_Imported (E) or else Is_Exported (E))
2416 and then No (Interface_Name (E))
2417 and then Convention (E) /= Convention_Stubbed
2418 and then Convention (E) /= Convention_Intrinsic
2420 Set_Encoded_Interface_Name
2421 (E, Get_Default_External_Name (E));
2423 -- If entity is an atomic object appearing in a declaration and
2424 -- the expression is an aggregate, assign it to a temporary to
2425 -- ensure that the actual assignment is done atomically rather
2426 -- than component-wise (the assignment to the temp may be done
2427 -- component-wise, but that is harmless).
2430 and then Nkind (Parent (E)) = N_Object_Declaration
2431 and then Present (Expression (Parent (E)))
2432 and then Nkind (Expression (Parent (E))) = N_Aggregate
2434 Is_Atomic_Aggregate (Expression (Parent (E)), Etype (E))
2439 -- For a subprogram, freeze all parameter types and also the return
2440 -- type (RM 13.14(14)). However skip this for internal subprograms.
2441 -- This is also the point where any extra formal parameters are
2442 -- created since we now know whether the subprogram will use a
2443 -- foreign convention.
2445 if Is_Subprogram (E) then
2446 if not Is_Internal (E) then
2450 Warn_Node : Node_Id;
2453 -- Loop through formals
2455 Formal := First_Formal (E);
2456 while Present (Formal) loop
2457 F_Type := Etype (Formal);
2458 Freeze_And_Append (F_Type, Loc, Result);
2460 if Is_Private_Type (F_Type)
2461 and then Is_Private_Type (Base_Type (F_Type))
2462 and then No (Full_View (Base_Type (F_Type)))
2463 and then not Is_Generic_Type (F_Type)
2464 and then not Is_Derived_Type (F_Type)
2466 -- If the type of a formal is incomplete, subprogram
2467 -- is being frozen prematurely. Within an instance
2468 -- (but not within a wrapper package) this is an
2469 -- artifact of our need to regard the end of an
2470 -- instantiation as a freeze point. Otherwise it is
2471 -- a definite error.
2474 Set_Is_Frozen (E, False);
2477 elsif not After_Last_Declaration
2478 and then not Freezing_Library_Level_Tagged_Type
2480 Error_Msg_Node_1 := F_Type;
2482 ("type& must be fully defined before this point",
2487 -- Check suspicious parameter for C function. These tests
2488 -- apply only to exported/imported subprograms.
2490 if Warn_On_Export_Import
2491 and then Comes_From_Source (E)
2492 and then (Convention (E) = Convention_C
2494 Convention (E) = Convention_CPP)
2495 and then (Is_Imported (E) or else Is_Exported (E))
2496 and then Convention (E) /= Convention (Formal)
2497 and then not Has_Warnings_Off (E)
2498 and then not Has_Warnings_Off (F_Type)
2499 and then not Has_Warnings_Off (Formal)
2501 -- Qualify mention of formals with subprogram name
2503 Error_Msg_Qual_Level := 1;
2505 -- Check suspicious use of fat C pointer
2507 if Is_Access_Type (F_Type)
2508 and then Esize (F_Type) > Ttypes.System_Address_Size
2511 ("?type of & does not correspond to C pointer!",
2514 -- Check suspicious return of boolean
2516 elsif Root_Type (F_Type) = Standard_Boolean
2517 and then Convention (F_Type) = Convention_Ada
2518 and then not Has_Warnings_Off (F_Type)
2519 and then not Has_Size_Clause (F_Type)
2520 and then VM_Target = No_VM
2522 Error_Msg_N ("& is an 8-bit Ada Boolean?", Formal);
2524 ("\use appropriate corresponding type in C "
2525 & "(e.g. char)?", Formal);
2527 -- Check suspicious tagged type
2529 elsif (Is_Tagged_Type (F_Type)
2530 or else (Is_Access_Type (F_Type)
2533 (Designated_Type (F_Type))))
2534 and then Convention (E) = Convention_C
2537 ("?& involves a tagged type which does not "
2538 & "correspond to any C type!", Formal);
2540 -- Check wrong convention subprogram pointer
2542 elsif Ekind (F_Type) = E_Access_Subprogram_Type
2543 and then not Has_Foreign_Convention (F_Type)
2546 ("?subprogram pointer & should "
2547 & "have foreign convention!", Formal);
2548 Error_Msg_Sloc := Sloc (F_Type);
2550 ("\?add Convention pragma to declaration of &#",
2554 -- Turn off name qualification after message output
2556 Error_Msg_Qual_Level := 0;
2559 -- Check for unconstrained array in exported foreign
2562 if Has_Foreign_Convention (E)
2563 and then not Is_Imported (E)
2564 and then Is_Array_Type (F_Type)
2565 and then not Is_Constrained (F_Type)
2566 and then Warn_On_Export_Import
2568 -- Exclude VM case, since both .NET and JVM can handle
2569 -- unconstrained arrays without a problem.
2571 and then VM_Target = No_VM
2573 Error_Msg_Qual_Level := 1;
2575 -- If this is an inherited operation, place the
2576 -- warning on the derived type declaration, rather
2577 -- than on the original subprogram.
2579 if Nkind (Original_Node (Parent (E))) =
2580 N_Full_Type_Declaration
2582 Warn_Node := Parent (E);
2584 if Formal = First_Formal (E) then
2586 ("?in inherited operation&", Warn_Node, E);
2589 Warn_Node := Formal;
2593 ("?type of argument& is unconstrained array",
2596 ("?foreign caller must pass bounds explicitly",
2598 Error_Msg_Qual_Level := 0;
2601 if not From_With_Type (F_Type) then
2602 if Is_Access_Type (F_Type) then
2603 F_Type := Designated_Type (F_Type);
2606 -- If the formal is an anonymous_access_to_subprogram
2607 -- freeze the subprogram type as well, to prevent
2608 -- scope anomalies in gigi, because there is no other
2609 -- clear point at which it could be frozen.
2611 if Is_Itype (Etype (Formal))
2612 and then Ekind (F_Type) = E_Subprogram_Type
2614 Freeze_And_Append (F_Type, Loc, Result);
2618 Next_Formal (Formal);
2621 -- Case of function: similar checks on return type
2623 if Ekind (E) = E_Function then
2625 -- Freeze return type
2627 R_Type := Etype (E);
2628 Freeze_And_Append (R_Type, Loc, Result);
2630 -- Check suspicious return type for C function
2632 if Warn_On_Export_Import
2633 and then (Convention (E) = Convention_C
2635 Convention (E) = Convention_CPP)
2636 and then (Is_Imported (E) or else Is_Exported (E))
2638 -- Check suspicious return of fat C pointer
2640 if Is_Access_Type (R_Type)
2641 and then Esize (R_Type) > Ttypes.System_Address_Size
2642 and then not Has_Warnings_Off (E)
2643 and then not Has_Warnings_Off (R_Type)
2646 ("?return type of& does not "
2647 & "correspond to C pointer!", E);
2649 -- Check suspicious return of boolean
2651 elsif Root_Type (R_Type) = Standard_Boolean
2652 and then Convention (R_Type) = Convention_Ada
2653 and then VM_Target = No_VM
2654 and then not Has_Warnings_Off (E)
2655 and then not Has_Warnings_Off (R_Type)
2656 and then not Has_Size_Clause (R_Type)
2659 N : constant Node_Id :=
2660 Result_Definition (Declaration_Node (E));
2663 ("return type of & is an 8-bit Ada Boolean?",
2666 ("\use appropriate corresponding type in C "
2667 & "(e.g. char)?", N, E);
2670 -- Check suspicious return tagged type
2672 elsif (Is_Tagged_Type (R_Type)
2673 or else (Is_Access_Type (R_Type)
2676 (Designated_Type (R_Type))))
2677 and then Convention (E) = Convention_C
2678 and then not Has_Warnings_Off (E)
2679 and then not Has_Warnings_Off (R_Type)
2682 ("?return type of & does not "
2683 & "correspond to C type!", E);
2685 -- Check return of wrong convention subprogram pointer
2687 elsif Ekind (R_Type) = E_Access_Subprogram_Type
2688 and then not Has_Foreign_Convention (R_Type)
2689 and then not Has_Warnings_Off (E)
2690 and then not Has_Warnings_Off (R_Type)
2693 ("?& should return a foreign "
2694 & "convention subprogram pointer", E);
2695 Error_Msg_Sloc := Sloc (R_Type);
2697 ("\?add Convention pragma to declaration of& #",
2702 -- Give warning for suspicous return of a result of an
2703 -- unconstrained array type in a foreign convention
2706 if Has_Foreign_Convention (E)
2708 -- We are looking for a return of unconstrained array
2710 and then Is_Array_Type (R_Type)
2711 and then not Is_Constrained (R_Type)
2713 -- Exclude imported routines, the warning does not
2714 -- belong on the import, but on the routine definition.
2716 and then not Is_Imported (E)
2718 -- Exclude VM case, since both .NET and JVM can handle
2719 -- return of unconstrained arrays without a problem.
2721 and then VM_Target = No_VM
2723 -- Check that general warning is enabled, and that it
2724 -- is not suppressed for this particular case.
2726 and then Warn_On_Export_Import
2727 and then not Has_Warnings_Off (E)
2728 and then not Has_Warnings_Off (R_Type)
2731 ("?foreign convention function& should not " &
2732 "return unconstrained array!", E);
2738 -- Must freeze its parent first if it is a derived subprogram
2740 if Present (Alias (E)) then
2741 Freeze_And_Append (Alias (E), Loc, Result);
2744 -- We don't freeze internal subprograms, because we don't normally
2745 -- want addition of extra formals or mechanism setting to happen
2746 -- for those. However we do pass through predefined dispatching
2747 -- cases, since extra formals may be needed in some cases, such as
2748 -- for the stream 'Input function (build-in-place formals).
2750 if not Is_Internal (E)
2751 or else Is_Predefined_Dispatching_Operation (E)
2753 Freeze_Subprogram (E);
2756 -- Here for other than a subprogram or type
2759 -- If entity has a type, and it is not a generic unit, then
2760 -- freeze it first (RM 13.14(10)).
2762 if Present (Etype (E))
2763 and then Ekind (E) /= E_Generic_Function
2765 Freeze_And_Append (Etype (E), Loc, Result);
2768 -- Special processing for objects created by object declaration
2770 if Nkind (Declaration_Node (E)) = N_Object_Declaration then
2772 -- Abstract type allowed only for C++ imported variables or
2775 -- Note: we inhibit this check for objects that do not come
2776 -- from source because there is at least one case (the
2777 -- expansion of x'class'input where x is abstract) where we
2778 -- legitimately generate an abstract object.
2780 if Is_Abstract_Type (Etype (E))
2781 and then Comes_From_Source (Parent (E))
2782 and then not (Is_Imported (E)
2783 and then Is_CPP_Class (Etype (E)))
2785 Error_Msg_N ("type of object cannot be abstract",
2786 Object_Definition (Parent (E)));
2788 if Is_CPP_Class (Etype (E)) then
2790 ("\} may need a cpp_constructor",
2791 Object_Definition (Parent (E)), Etype (E));
2795 -- For object created by object declaration, perform required
2796 -- categorization (preelaborate and pure) checks. Defer these
2797 -- checks to freeze time since pragma Import inhibits default
2798 -- initialization and thus pragma Import affects these checks.
2800 Validate_Object_Declaration (Declaration_Node (E));
2802 -- If there is an address clause, check that it is valid
2804 Check_Address_Clause (E);
2806 -- If the object needs any kind of default initialization, an
2807 -- error must be issued if No_Default_Initialization applies.
2808 -- The check doesn't apply to imported objects, which are not
2809 -- ever default initialized, and is why the check is deferred
2810 -- until freezing, at which point we know if Import applies.
2811 -- Deferred constants are also exempted from this test because
2812 -- their completion is explicit, or through an import pragma.
2814 if Ekind (E) = E_Constant
2815 and then Present (Full_View (E))
2819 elsif Comes_From_Source (E)
2820 and then not Is_Imported (E)
2821 and then not Has_Init_Expression (Declaration_Node (E))
2823 ((Has_Non_Null_Base_Init_Proc (Etype (E))
2824 and then not No_Initialization (Declaration_Node (E))
2825 and then not Is_Value_Type (Etype (E))
2826 and then not Suppress_Init_Proc (Etype (E)))
2828 (Needs_Simple_Initialization (Etype (E))
2829 and then not Is_Internal (E)))
2831 Has_Default_Initialization := True;
2833 (No_Default_Initialization, Declaration_Node (E));
2836 -- Check that a Thread_Local_Storage variable does not have
2837 -- default initialization, and any explicit initialization must
2838 -- either be the null constant or a static constant.
2840 if Has_Pragma_Thread_Local_Storage (E) then
2842 Decl : constant Node_Id := Declaration_Node (E);
2844 if Has_Default_Initialization
2846 (Has_Init_Expression (Decl)
2848 (No (Expression (Decl))
2850 (Is_Static_Expression (Expression (Decl))
2852 Nkind (Expression (Decl)) = N_Null)))
2855 ("Thread_Local_Storage variable& is "
2856 & "improperly initialized", Decl, E);
2858 ("\only allowed initialization is explicit "
2859 & "NULL or static expression", Decl, E);
2864 -- For imported objects, set Is_Public unless there is also an
2865 -- address clause, which means that there is no external symbol
2866 -- needed for the Import (Is_Public may still be set for other
2867 -- unrelated reasons). Note that we delayed this processing
2868 -- till freeze time so that we can be sure not to set the flag
2869 -- if there is an address clause. If there is such a clause,
2870 -- then the only purpose of the Import pragma is to suppress
2871 -- implicit initialization.
2874 and then No (Address_Clause (E))
2879 -- For convention C objects of an enumeration type, warn if
2880 -- the size is not integer size and no explicit size given.
2881 -- Skip warning for Boolean, and Character, assume programmer
2882 -- expects 8-bit sizes for these cases.
2884 if (Convention (E) = Convention_C
2886 Convention (E) = Convention_CPP)
2887 and then Is_Enumeration_Type (Etype (E))
2888 and then not Is_Character_Type (Etype (E))
2889 and then not Is_Boolean_Type (Etype (E))
2890 and then Esize (Etype (E)) < Standard_Integer_Size
2891 and then not Has_Size_Clause (E)
2893 Error_Msg_Uint_1 := UI_From_Int (Standard_Integer_Size);
2895 ("?convention C enumeration object has size less than ^",
2897 Error_Msg_N ("\?use explicit size clause to set size", E);
2901 -- Check that a constant which has a pragma Volatile[_Components]
2902 -- or Atomic[_Components] also has a pragma Import (RM C.6(13)).
2904 -- Note: Atomic[_Components] also sets Volatile[_Components]
2906 if Ekind (E) = E_Constant
2907 and then (Has_Volatile_Components (E) or else Is_Volatile (E))
2908 and then not Is_Imported (E)
2910 -- Make sure we actually have a pragma, and have not merely
2911 -- inherited the indication from elsewhere (e.g. an address
2912 -- clause, which is not good enough in RM terms!)
2914 if Has_Rep_Pragma (E, Name_Atomic)
2916 Has_Rep_Pragma (E, Name_Atomic_Components)
2919 ("stand alone atomic constant must be " &
2920 "imported (RM C.6(13))", E);
2922 elsif Has_Rep_Pragma (E, Name_Volatile)
2924 Has_Rep_Pragma (E, Name_Volatile_Components)
2927 ("stand alone volatile constant must be " &
2928 "imported (RM C.6(13))", E);
2932 -- Static objects require special handling
2934 if (Ekind (E) = E_Constant or else Ekind (E) = E_Variable)
2935 and then Is_Statically_Allocated (E)
2937 Freeze_Static_Object (E);
2940 -- Remaining step is to layout objects
2942 if Ekind (E) = E_Variable
2944 Ekind (E) = E_Constant
2946 Ekind (E) = E_Loop_Parameter
2954 -- Case of a type or subtype being frozen
2957 -- We used to check here that a full type must have preelaborable
2958 -- initialization if it completes a private type specified with
2959 -- pragma Preelaborable_Intialization, but that missed cases where
2960 -- the types occur within a generic package, since the freezing
2961 -- that occurs within a containing scope generally skips traversal
2962 -- of a generic unit's declarations (those will be frozen within
2963 -- instances). This check was moved to Analyze_Package_Specification.
2965 -- The type may be defined in a generic unit. This can occur when
2966 -- freezing a generic function that returns the type (which is
2967 -- defined in a parent unit). It is clearly meaningless to freeze
2968 -- this type. However, if it is a subtype, its size may be determi-
2969 -- nable and used in subsequent checks, so might as well try to
2972 if Present (Scope (E))
2973 and then Is_Generic_Unit (Scope (E))
2975 Check_Compile_Time_Size (E);
2979 -- Deal with special cases of freezing for subtype
2981 if E /= Base_Type (E) then
2983 -- Before we do anything else, a specialized test for the case of
2984 -- a size given for an array where the array needs to be packed,
2985 -- but was not so the size cannot be honored. This would of course
2986 -- be caught by the backend, and indeed we don't catch all cases.
2987 -- The point is that we can give a better error message in those
2988 -- cases that we do catch with the circuitry here. Also if pragma
2989 -- Implicit_Packing is set, this is where the packing occurs.
2991 -- The reason we do this so early is that the processing in the
2992 -- automatic packing case affects the layout of the base type, so
2993 -- it must be done before we freeze the base type.
2995 if Is_Array_Type (E) then
2998 Ctyp : constant Entity_Id := Component_Type (E);
3001 -- Check enabling conditions. These are straightforward
3002 -- except for the test for a limited composite type. This
3003 -- eliminates the rare case of a array of limited components
3004 -- where there are issues of whether or not we can go ahead
3005 -- and pack the array (since we can't freely pack and unpack
3006 -- arrays if they are limited).
3008 -- Note that we check the root type explicitly because the
3009 -- whole point is we are doing this test before we have had
3010 -- a chance to freeze the base type (and it is that freeze
3011 -- action that causes stuff to be inherited).
3013 if Present (Size_Clause (E))
3014 and then Known_Static_Esize (E)
3015 and then not Is_Packed (E)
3016 and then not Has_Pragma_Pack (E)
3017 and then Number_Dimensions (E) = 1
3018 and then not Has_Component_Size_Clause (E)
3019 and then Known_Static_Esize (Ctyp)
3020 and then not Is_Limited_Composite (E)
3021 and then not Is_Packed (Root_Type (E))
3022 and then not Has_Component_Size_Clause (Root_Type (E))
3023 and then not CodePeer_Mode
3025 Get_Index_Bounds (First_Index (E), Lo, Hi);
3027 if Compile_Time_Known_Value (Lo)
3028 and then Compile_Time_Known_Value (Hi)
3029 and then Known_Static_RM_Size (Ctyp)
3030 and then RM_Size (Ctyp) < 64
3033 Lov : constant Uint := Expr_Value (Lo);
3034 Hiv : constant Uint := Expr_Value (Hi);
3035 Len : constant Uint := UI_Max
3038 Rsiz : constant Uint := RM_Size (Ctyp);
3039 SZ : constant Node_Id := Size_Clause (E);
3040 Btyp : constant Entity_Id := Base_Type (E);
3042 -- What we are looking for here is the situation where
3043 -- the RM_Size given would be exactly right if there
3044 -- was a pragma Pack (resulting in the component size
3045 -- being the same as the RM_Size). Furthermore, the
3046 -- component type size must be an odd size (not a
3047 -- multiple of storage unit). If the component RM size
3048 -- is an exact number of storage units that is a power
3049 -- of two, the array is not packed and has a standard
3053 if RM_Size (E) = Len * Rsiz
3054 and then Rsiz mod System_Storage_Unit /= 0
3056 -- For implicit packing mode, just set the
3057 -- component size silently.
3059 if Implicit_Packing then
3060 Set_Component_Size (Btyp, Rsiz);
3061 Set_Is_Bit_Packed_Array (Btyp);
3062 Set_Is_Packed (Btyp);
3063 Set_Has_Non_Standard_Rep (Btyp);
3065 -- Otherwise give an error message
3069 ("size given for& too small", SZ, E);
3070 Error_Msg_N -- CODEFIX
3071 ("\use explicit pragma Pack "
3072 & "or use pragma Implicit_Packing", SZ);
3075 elsif RM_Size (E) = Len * Rsiz
3076 and then Implicit_Packing
3078 (Rsiz / System_Storage_Unit = 1
3079 or else Rsiz / System_Storage_Unit = 2
3080 or else Rsiz / System_Storage_Unit = 4)
3083 -- Not a packed array, but indicate the desired
3084 -- component size, for the back-end.
3086 Set_Component_Size (Btyp, Rsiz);
3094 -- If ancestor subtype present, freeze that first. Note that this
3095 -- will also get the base type frozen.
3097 Atype := Ancestor_Subtype (E);
3099 if Present (Atype) then
3100 Freeze_And_Append (Atype, Loc, Result);
3102 -- Otherwise freeze the base type of the entity before freezing
3103 -- the entity itself (RM 13.14(15)).
3105 elsif E /= Base_Type (E) then
3106 Freeze_And_Append (Base_Type (E), Loc, Result);
3109 -- For a derived type, freeze its parent type first (RM 13.14(15))
3111 elsif Is_Derived_Type (E) then
3112 Freeze_And_Append (Etype (E), Loc, Result);
3113 Freeze_And_Append (First_Subtype (Etype (E)), Loc, Result);
3116 -- For array type, freeze index types and component type first
3117 -- before freezing the array (RM 13.14(15)).
3119 if Is_Array_Type (E) then
3121 Ctyp : constant Entity_Id := Component_Type (E);
3123 Non_Standard_Enum : Boolean := False;
3124 -- Set true if any of the index types is an enumeration type
3125 -- with a non-standard representation.
3128 Freeze_And_Append (Ctyp, Loc, Result);
3130 Indx := First_Index (E);
3131 while Present (Indx) loop
3132 Freeze_And_Append (Etype (Indx), Loc, Result);
3134 if Is_Enumeration_Type (Etype (Indx))
3135 and then Has_Non_Standard_Rep (Etype (Indx))
3137 Non_Standard_Enum := True;
3143 -- Processing that is done only for base types
3145 if Ekind (E) = E_Array_Type then
3147 -- Propagate flags for component type
3149 if Is_Controlled (Component_Type (E))
3150 or else Has_Controlled_Component (Ctyp)
3152 Set_Has_Controlled_Component (E);
3155 if Has_Unchecked_Union (Component_Type (E)) then
3156 Set_Has_Unchecked_Union (E);
3159 -- If packing was requested or if the component size was set
3160 -- explicitly, then see if bit packing is required. This
3161 -- processing is only done for base types, since all the
3162 -- representation aspects involved are type-related. This
3163 -- is not just an optimization, if we start processing the
3164 -- subtypes, they interfere with the settings on the base
3165 -- type (this is because Is_Packed has a slightly different
3166 -- meaning before and after freezing).
3173 if (Is_Packed (E) or else Has_Pragma_Pack (E))
3174 and then not Has_Atomic_Components (E)
3175 and then Known_Static_RM_Size (Ctyp)
3177 Csiz := UI_Max (RM_Size (Ctyp), 1);
3179 elsif Known_Component_Size (E) then
3180 Csiz := Component_Size (E);
3182 elsif not Known_Static_Esize (Ctyp) then
3186 Esiz := Esize (Ctyp);
3188 -- We can set the component size if it is less than
3189 -- 16, rounding it up to the next storage unit size.
3193 elsif Esiz <= 16 then
3199 -- Set component size up to match alignment if it
3200 -- would otherwise be less than the alignment. This
3201 -- deals with cases of types whose alignment exceeds
3202 -- their size (padded types).
3206 A : constant Uint := Alignment_In_Bits (Ctyp);
3215 -- Case of component size that may result in packing
3217 if 1 <= Csiz and then Csiz <= 64 then
3219 Ent : constant Entity_Id :=
3221 Pack_Pragma : constant Node_Id :=
3222 Get_Rep_Pragma (Ent, Name_Pack);
3223 Comp_Size_C : constant Node_Id :=
3224 Get_Attribute_Definition_Clause
3225 (Ent, Attribute_Component_Size);
3227 -- Warn if we have pack and component size so that
3228 -- the pack is ignored.
3230 -- Note: here we must check for the presence of a
3231 -- component size before checking for a Pack pragma
3232 -- to deal with the case where the array type is a
3233 -- derived type whose parent is currently private.
3235 if Present (Comp_Size_C)
3236 and then Has_Pragma_Pack (Ent)
3238 Error_Msg_Sloc := Sloc (Comp_Size_C);
3240 ("?pragma Pack for& ignored!",
3243 ("\?explicit component size given#!",
3247 -- Set component size if not already set by a
3248 -- component size clause.
3250 if not Present (Comp_Size_C) then
3251 Set_Component_Size (E, Csiz);
3254 -- Check for base type of 8, 16, 32 bits, where an
3255 -- unsigned subtype has a length one less than the
3256 -- base type (e.g. Natural subtype of Integer).
3258 -- In such cases, if a component size was not set
3259 -- explicitly, then generate a warning.
3261 if Has_Pragma_Pack (E)
3262 and then not Present (Comp_Size_C)
3264 (Csiz = 7 or else Csiz = 15 or else Csiz = 31)
3265 and then Esize (Base_Type (Ctyp)) = Csiz + 1
3267 Error_Msg_Uint_1 := Csiz;
3269 if Present (Pack_Pragma) then
3271 ("?pragma Pack causes component size "
3272 & "to be ^!", Pack_Pragma);
3274 ("\?use Component_Size to set "
3275 & "desired value!", Pack_Pragma);
3279 -- Actual packing is not needed for 8, 16, 32, 64.
3280 -- Also not needed for 24 if alignment is 1.
3286 or else (Csiz = 24 and then Alignment (Ctyp) = 1)
3288 -- Here the array was requested to be packed,
3289 -- but the packing request had no effect, so
3290 -- Is_Packed is reset.
3292 -- Note: semantically this means that we lose
3293 -- track of the fact that a derived type
3294 -- inherited a pragma Pack that was non-
3295 -- effective, but that seems fine.
3297 -- We regard a Pack pragma as a request to set
3298 -- a representation characteristic, and this
3299 -- request may be ignored.
3301 Set_Is_Packed (Base_Type (E), False);
3303 -- In all other cases, packing is indeed needed
3306 Set_Has_Non_Standard_Rep (Base_Type (E));
3307 Set_Is_Bit_Packed_Array (Base_Type (E));
3308 Set_Is_Packed (Base_Type (E));
3314 -- Processing that is done only for subtypes
3317 -- Acquire alignment from base type
3319 if Unknown_Alignment (E) then
3320 Set_Alignment (E, Alignment (Base_Type (E)));
3321 Adjust_Esize_Alignment (E);
3325 -- For bit-packed arrays, check the size
3327 if Is_Bit_Packed_Array (E) and then Known_RM_Size (E) then
3329 SizC : constant Node_Id := Size_Clause (E);
3332 pragma Warnings (Off, Discard);
3335 -- It is not clear if it is possible to have no size
3336 -- clause at this stage, but it is not worth worrying
3337 -- about. Post error on the entity name in the size
3338 -- clause if present, else on the type entity itself.
3340 if Present (SizC) then
3341 Check_Size (Name (SizC), E, RM_Size (E), Discard);
3343 Check_Size (E, E, RM_Size (E), Discard);
3348 -- If any of the index types was an enumeration type with
3349 -- a non-standard rep clause, then we indicate that the
3350 -- array type is always packed (even if it is not bit packed).
3352 if Non_Standard_Enum then
3353 Set_Has_Non_Standard_Rep (Base_Type (E));
3354 Set_Is_Packed (Base_Type (E));
3357 Set_Component_Alignment_If_Not_Set (E);
3359 -- If the array is packed, we must create the packed array
3360 -- type to be used to actually implement the type. This is
3361 -- only needed for real array types (not for string literal
3362 -- types, since they are present only for the front end).
3365 and then Ekind (E) /= E_String_Literal_Subtype
3367 Create_Packed_Array_Type (E);
3368 Freeze_And_Append (Packed_Array_Type (E), Loc, Result);
3370 -- Size information of packed array type is copied to the
3371 -- array type, since this is really the representation. But
3372 -- do not override explicit existing size values. If the
3373 -- ancestor subtype is constrained the packed_array_type
3374 -- will be inherited from it, but the size may have been
3375 -- provided already, and must not be overridden either.
3377 if not Has_Size_Clause (E)
3379 (No (Ancestor_Subtype (E))
3380 or else not Has_Size_Clause (Ancestor_Subtype (E)))
3382 Set_Esize (E, Esize (Packed_Array_Type (E)));
3383 Set_RM_Size (E, RM_Size (Packed_Array_Type (E)));
3386 if not Has_Alignment_Clause (E) then
3387 Set_Alignment (E, Alignment (Packed_Array_Type (E)));
3391 -- For non-packed arrays set the alignment of the array to the
3392 -- alignment of the component type if it is unknown. Skip this
3393 -- in atomic case (atomic arrays may need larger alignments).
3395 if not Is_Packed (E)
3396 and then Unknown_Alignment (E)
3397 and then Known_Alignment (Ctyp)
3398 and then Known_Static_Component_Size (E)
3399 and then Known_Static_Esize (Ctyp)
3400 and then Esize (Ctyp) = Component_Size (E)
3401 and then not Is_Atomic (E)
3403 Set_Alignment (E, Alignment (Component_Type (E)));
3407 -- For a class-wide type, the corresponding specific type is
3408 -- frozen as well (RM 13.14(15))
3410 elsif Is_Class_Wide_Type (E) then
3411 Freeze_And_Append (Root_Type (E), Loc, Result);
3413 -- If the base type of the class-wide type is still incomplete,
3414 -- the class-wide remains unfrozen as well. This is legal when
3415 -- E is the formal of a primitive operation of some other type
3416 -- which is being frozen.
3418 if not Is_Frozen (Root_Type (E)) then
3419 Set_Is_Frozen (E, False);
3423 -- If the Class_Wide_Type is an Itype (when type is the anonymous
3424 -- parent of a derived type) and it is a library-level entity,
3425 -- generate an itype reference for it. Otherwise, its first
3426 -- explicit reference may be in an inner scope, which will be
3427 -- rejected by the back-end.
3430 and then Is_Compilation_Unit (Scope (E))
3433 Ref : constant Node_Id := Make_Itype_Reference (Loc);
3438 Result := New_List (Ref);
3440 Append (Ref, Result);
3445 -- The equivalent type associated with a class-wide subtype needs
3446 -- to be frozen to ensure that its layout is done.
3448 if Ekind (E) = E_Class_Wide_Subtype
3449 and then Present (Equivalent_Type (E))
3451 Freeze_And_Append (Equivalent_Type (E), Loc, Result);
3454 -- For a record (sub)type, freeze all the component types (RM
3455 -- 13.14(15). We test for E_Record_(sub)Type here, rather than using
3456 -- Is_Record_Type, because we don't want to attempt the freeze for
3457 -- the case of a private type with record extension (we will do that
3458 -- later when the full type is frozen).
3460 elsif Ekind (E) = E_Record_Type
3461 or else Ekind (E) = E_Record_Subtype
3463 Freeze_Record_Type (E);
3465 -- For a concurrent type, freeze corresponding record type. This
3466 -- does not correspond to any specific rule in the RM, but the
3467 -- record type is essentially part of the concurrent type.
3468 -- Freeze as well all local entities. This includes record types
3469 -- created for entry parameter blocks, and whatever local entities
3470 -- may appear in the private part.
3472 elsif Is_Concurrent_Type (E) then
3473 if Present (Corresponding_Record_Type (E)) then
3475 (Corresponding_Record_Type (E), Loc, Result);
3478 Comp := First_Entity (E);
3479 while Present (Comp) loop
3480 if Is_Type (Comp) then
3481 Freeze_And_Append (Comp, Loc, Result);
3483 elsif (Ekind (Comp)) /= E_Function then
3484 if Is_Itype (Etype (Comp))
3485 and then Underlying_Type (Scope (Etype (Comp))) = E
3487 Undelay_Type (Etype (Comp));
3490 Freeze_And_Append (Etype (Comp), Loc, Result);
3496 -- Private types are required to point to the same freeze node as
3497 -- their corresponding full views. The freeze node itself has to
3498 -- point to the partial view of the entity (because from the partial
3499 -- view, we can retrieve the full view, but not the reverse).
3500 -- However, in order to freeze correctly, we need to freeze the full
3501 -- view. If we are freezing at the end of a scope (or within the
3502 -- scope of the private type), the partial and full views will have
3503 -- been swapped, the full view appears first in the entity chain and
3504 -- the swapping mechanism ensures that the pointers are properly set
3507 -- If we encounter the partial view before the full view (e.g. when
3508 -- freezing from another scope), we freeze the full view, and then
3509 -- set the pointers appropriately since we cannot rely on swapping to
3510 -- fix things up (subtypes in an outer scope might not get swapped).
3512 elsif Is_Incomplete_Or_Private_Type (E)
3513 and then not Is_Generic_Type (E)
3515 -- The construction of the dispatch table associated with library
3516 -- level tagged types forces freezing of all the primitives of the
3517 -- type, which may cause premature freezing of the partial view.
3521 -- type T is tagged private;
3522 -- type DT is new T with private;
3523 -- procedure Prim (X : in out T; Y : in out DT'class);
3525 -- type T is tagged null record;
3527 -- type DT is new T with null record;
3530 -- In this case the type will be frozen later by the usual
3531 -- mechanism: an object declaration, an instantiation, or the
3532 -- end of a declarative part.
3534 if Is_Library_Level_Tagged_Type (E)
3535 and then not Present (Full_View (E))
3537 Set_Is_Frozen (E, False);
3540 -- Case of full view present
3542 elsif Present (Full_View (E)) then
3544 -- If full view has already been frozen, then no further
3545 -- processing is required
3547 if Is_Frozen (Full_View (E)) then
3549 Set_Has_Delayed_Freeze (E, False);
3550 Set_Freeze_Node (E, Empty);
3551 Check_Debug_Info_Needed (E);
3553 -- Otherwise freeze full view and patch the pointers so that
3554 -- the freeze node will elaborate both views in the back-end.
3558 Full : constant Entity_Id := Full_View (E);
3561 if Is_Private_Type (Full)
3562 and then Present (Underlying_Full_View (Full))
3565 (Underlying_Full_View (Full), Loc, Result);
3568 Freeze_And_Append (Full, Loc, Result);
3570 if Has_Delayed_Freeze (E) then
3571 F_Node := Freeze_Node (Full);
3573 if Present (F_Node) then
3574 Set_Freeze_Node (E, F_Node);
3575 Set_Entity (F_Node, E);
3578 -- {Incomplete,Private}_Subtypes with Full_Views
3579 -- constrained by discriminants.
3581 Set_Has_Delayed_Freeze (E, False);
3582 Set_Freeze_Node (E, Empty);
3587 Check_Debug_Info_Needed (E);
3590 -- AI-117 requires that the convention of a partial view be the
3591 -- same as the convention of the full view. Note that this is a
3592 -- recognized breach of privacy, but it's essential for logical
3593 -- consistency of representation, and the lack of a rule in
3594 -- RM95 was an oversight.
3596 Set_Convention (E, Convention (Full_View (E)));
3598 Set_Size_Known_At_Compile_Time (E,
3599 Size_Known_At_Compile_Time (Full_View (E)));
3601 -- Size information is copied from the full view to the
3602 -- incomplete or private view for consistency.
3604 -- We skip this is the full view is not a type. This is very
3605 -- strange of course, and can only happen as a result of
3606 -- certain illegalities, such as a premature attempt to derive
3607 -- from an incomplete type.
3609 if Is_Type (Full_View (E)) then
3610 Set_Size_Info (E, Full_View (E));
3611 Set_RM_Size (E, RM_Size (Full_View (E)));
3616 -- Case of no full view present. If entity is derived or subtype,
3617 -- it is safe to freeze, correctness depends on the frozen status
3618 -- of parent. Otherwise it is either premature usage, or a Taft
3619 -- amendment type, so diagnosis is at the point of use and the
3620 -- type might be frozen later.
3622 elsif E /= Base_Type (E)
3623 or else Is_Derived_Type (E)
3628 Set_Is_Frozen (E, False);
3632 -- For access subprogram, freeze types of all formals, the return
3633 -- type was already frozen, since it is the Etype of the function.
3634 -- Formal types can be tagged Taft amendment types, but otherwise
3635 -- they cannot be incomplete.
3637 elsif Ekind (E) = E_Subprogram_Type then
3638 Formal := First_Formal (E);
3640 while Present (Formal) loop
3641 if Ekind (Etype (Formal)) = E_Incomplete_Type
3642 and then No (Full_View (Etype (Formal)))
3643 and then not Is_Value_Type (Etype (Formal))
3645 if Is_Tagged_Type (Etype (Formal)) then
3649 ("invalid use of incomplete type&", E, Etype (Formal));
3653 Freeze_And_Append (Etype (Formal), Loc, Result);
3654 Next_Formal (Formal);
3657 Freeze_Subprogram (E);
3659 -- For access to a protected subprogram, freeze the equivalent type
3660 -- (however this is not set if we are not generating code or if this
3661 -- is an anonymous type used just for resolution).
3663 elsif Is_Access_Protected_Subprogram_Type (E) then
3664 if Present (Equivalent_Type (E)) then
3665 Freeze_And_Append (Equivalent_Type (E), Loc, Result);
3669 -- Generic types are never seen by the back-end, and are also not
3670 -- processed by the expander (since the expander is turned off for
3671 -- generic processing), so we never need freeze nodes for them.
3673 if Is_Generic_Type (E) then
3677 -- Some special processing for non-generic types to complete
3678 -- representation details not known till the freeze point.
3680 if Is_Fixed_Point_Type (E) then
3681 Freeze_Fixed_Point_Type (E);
3683 -- Some error checks required for ordinary fixed-point type. Defer
3684 -- these till the freeze-point since we need the small and range
3685 -- values. We only do these checks for base types
3687 if Is_Ordinary_Fixed_Point_Type (E)
3688 and then E = Base_Type (E)
3690 if Small_Value (E) < Ureal_2_M_80 then
3691 Error_Msg_Name_1 := Name_Small;
3693 ("`&''%` too small, minimum allowed is 2.0'*'*(-80)", E);
3695 elsif Small_Value (E) > Ureal_2_80 then
3696 Error_Msg_Name_1 := Name_Small;
3698 ("`&''%` too large, maximum allowed is 2.0'*'*80", E);
3701 if Expr_Value_R (Type_Low_Bound (E)) < Ureal_M_10_36 then
3702 Error_Msg_Name_1 := Name_First;
3704 ("`&''%` too small, minimum allowed is -10.0'*'*36", E);
3707 if Expr_Value_R (Type_High_Bound (E)) > Ureal_10_36 then
3708 Error_Msg_Name_1 := Name_Last;
3710 ("`&''%` too large, maximum allowed is 10.0'*'*36", E);
3714 elsif Is_Enumeration_Type (E) then
3715 Freeze_Enumeration_Type (E);
3717 elsif Is_Integer_Type (E) then
3718 Adjust_Esize_For_Alignment (E);
3720 if Is_Modular_Integer_Type (E)
3721 and then Warn_On_Suspicious_Modulus_Value
3723 Check_Suspicious_Modulus (E);
3726 elsif Is_Access_Type (E) then
3728 -- Check restriction for standard storage pool
3730 if No (Associated_Storage_Pool (E)) then
3731 Check_Restriction (No_Standard_Storage_Pools, E);
3734 -- Deal with error message for pure access type. This is not an
3735 -- error in Ada 2005 if there is no pool (see AI-366).
3737 if Is_Pure_Unit_Access_Type (E)
3738 and then (Ada_Version < Ada_05
3739 or else not No_Pool_Assigned (E))
3741 Error_Msg_N ("named access type not allowed in pure unit", E);
3743 if Ada_Version >= Ada_05 then
3745 ("\would be legal if Storage_Size of 0 given?", E);
3747 elsif No_Pool_Assigned (E) then
3749 ("\would be legal in Ada 2005?", E);
3753 ("\would be legal in Ada 2005 if "
3754 & "Storage_Size of 0 given?", E);
3759 -- Case of composite types
3761 if Is_Composite_Type (E) then
3763 -- AI-117 requires that all new primitives of a tagged type must
3764 -- inherit the convention of the full view of the type. Inherited
3765 -- and overriding operations are defined to inherit the convention
3766 -- of their parent or overridden subprogram (also specified in
3767 -- AI-117), which will have occurred earlier (in Derive_Subprogram
3768 -- and New_Overloaded_Entity). Here we set the convention of
3769 -- primitives that are still convention Ada, which will ensure
3770 -- that any new primitives inherit the type's convention. Class-
3771 -- wide types can have a foreign convention inherited from their
3772 -- specific type, but are excluded from this since they don't have
3773 -- any associated primitives.
3775 if Is_Tagged_Type (E)
3776 and then not Is_Class_Wide_Type (E)
3777 and then Convention (E) /= Convention_Ada
3780 Prim_List : constant Elist_Id := Primitive_Operations (E);
3783 Prim := First_Elmt (Prim_List);
3784 while Present (Prim) loop
3785 if Convention (Node (Prim)) = Convention_Ada then
3786 Set_Convention (Node (Prim), Convention (E));
3795 -- Now that all types from which E may depend are frozen, see if the
3796 -- size is known at compile time, if it must be unsigned, or if
3797 -- strict alignment is required
3799 Check_Compile_Time_Size (E);
3800 Check_Unsigned_Type (E);
3802 if Base_Type (E) = E then
3803 Check_Strict_Alignment (E);
3806 -- Do not allow a size clause for a type which does not have a size
3807 -- that is known at compile time
3809 if Has_Size_Clause (E)
3810 and then not Size_Known_At_Compile_Time (E)
3812 -- Suppress this message if errors posted on E, even if we are
3813 -- in all errors mode, since this is often a junk message
3815 if not Error_Posted (E) then
3817 ("size clause not allowed for variable length type",
3822 -- Remaining process is to set/verify the representation information,
3823 -- in particular the size and alignment values. This processing is
3824 -- not required for generic types, since generic types do not play
3825 -- any part in code generation, and so the size and alignment values
3826 -- for such types are irrelevant.
3828 if Is_Generic_Type (E) then
3831 -- Otherwise we call the layout procedure
3837 -- End of freeze processing for type entities
3840 -- Here is where we logically freeze the current entity. If it has a
3841 -- freeze node, then this is the point at which the freeze node is
3842 -- linked into the result list.
3844 if Has_Delayed_Freeze (E) then
3846 -- If a freeze node is already allocated, use it, otherwise allocate
3847 -- a new one. The preallocation happens in the case of anonymous base
3848 -- types, where we preallocate so that we can set First_Subtype_Link.
3849 -- Note that we reset the Sloc to the current freeze location.
3851 if Present (Freeze_Node (E)) then
3852 F_Node := Freeze_Node (E);
3853 Set_Sloc (F_Node, Loc);
3856 F_Node := New_Node (N_Freeze_Entity, Loc);
3857 Set_Freeze_Node (E, F_Node);
3858 Set_Access_Types_To_Process (F_Node, No_Elist);
3859 Set_TSS_Elist (F_Node, No_Elist);
3860 Set_Actions (F_Node, No_List);
3863 Set_Entity (F_Node, E);
3865 if Result = No_List then
3866 Result := New_List (F_Node);
3868 Append (F_Node, Result);
3871 -- A final pass over record types with discriminants. If the type
3872 -- has an incomplete declaration, there may be constrained access
3873 -- subtypes declared elsewhere, which do not depend on the discrimi-
3874 -- nants of the type, and which are used as component types (i.e.
3875 -- the full view is a recursive type). The designated types of these
3876 -- subtypes can only be elaborated after the type itself, and they
3877 -- need an itype reference.
3879 if Ekind (E) = E_Record_Type
3880 and then Has_Discriminants (E)
3888 Comp := First_Component (E);
3890 while Present (Comp) loop
3891 Typ := Etype (Comp);
3893 if Ekind (Comp) = E_Component
3894 and then Is_Access_Type (Typ)
3895 and then Scope (Typ) /= E
3896 and then Base_Type (Designated_Type (Typ)) = E
3897 and then Is_Itype (Designated_Type (Typ))
3899 IR := Make_Itype_Reference (Sloc (Comp));
3900 Set_Itype (IR, Designated_Type (Typ));
3901 Append (IR, Result);
3904 Next_Component (Comp);
3910 -- When a type is frozen, the first subtype of the type is frozen as
3911 -- well (RM 13.14(15)). This has to be done after freezing the type,
3912 -- since obviously the first subtype depends on its own base type.
3915 Freeze_And_Append (First_Subtype (E), Loc, Result);
3917 -- If we just froze a tagged non-class wide record, then freeze the
3918 -- corresponding class-wide type. This must be done after the tagged
3919 -- type itself is frozen, because the class-wide type refers to the
3920 -- tagged type which generates the class.
3922 if Is_Tagged_Type (E)
3923 and then not Is_Class_Wide_Type (E)
3924 and then Present (Class_Wide_Type (E))
3926 Freeze_And_Append (Class_Wide_Type (E), Loc, Result);
3930 Check_Debug_Info_Needed (E);
3932 -- Special handling for subprograms
3934 if Is_Subprogram (E) then
3936 -- If subprogram has address clause then reset Is_Public flag, since
3937 -- we do not want the backend to generate external references.
3939 if Present (Address_Clause (E))
3940 and then not Is_Library_Level_Entity (E)
3942 Set_Is_Public (E, False);
3944 -- If no address clause and not intrinsic, then for imported
3945 -- subprogram in main unit, generate descriptor if we are in
3946 -- Propagate_Exceptions mode.
3948 elsif Propagate_Exceptions
3949 and then Is_Imported (E)
3950 and then not Is_Intrinsic_Subprogram (E)
3951 and then Convention (E) /= Convention_Stubbed
3953 if Result = No_List then
3954 Result := Empty_List;
3962 -----------------------------
3963 -- Freeze_Enumeration_Type --
3964 -----------------------------
3966 procedure Freeze_Enumeration_Type (Typ : Entity_Id) is
3968 -- By default, if no size clause is present, an enumeration type with
3969 -- Convention C is assumed to interface to a C enum, and has integer
3970 -- size. This applies to types. For subtypes, verify that its base
3971 -- type has no size clause either.
3973 if Has_Foreign_Convention (Typ)
3974 and then not Has_Size_Clause (Typ)
3975 and then not Has_Size_Clause (Base_Type (Typ))
3976 and then Esize (Typ) < Standard_Integer_Size
3978 Init_Esize (Typ, Standard_Integer_Size);
3981 -- If the enumeration type interfaces to C, and it has a size clause
3982 -- that specifies less than int size, it warrants a warning. The
3983 -- user may intend the C type to be an enum or a char, so this is
3984 -- not by itself an error that the Ada compiler can detect, but it
3985 -- it is a worth a heads-up. For Boolean and Character types we
3986 -- assume that the programmer has the proper C type in mind.
3988 if Convention (Typ) = Convention_C
3989 and then Has_Size_Clause (Typ)
3990 and then Esize (Typ) /= Esize (Standard_Integer)
3991 and then not Is_Boolean_Type (Typ)
3992 and then not Is_Character_Type (Typ)
3995 ("C enum types have the size of a C int?", Size_Clause (Typ));
3998 Adjust_Esize_For_Alignment (Typ);
4000 end Freeze_Enumeration_Type;
4002 -----------------------
4003 -- Freeze_Expression --
4004 -----------------------
4006 procedure Freeze_Expression (N : Node_Id) is
4007 In_Spec_Exp : constant Boolean := In_Spec_Expression;
4010 Desig_Typ : Entity_Id;
4014 Freeze_Outside : Boolean := False;
4015 -- This flag is set true if the entity must be frozen outside the
4016 -- current subprogram. This happens in the case of expander generated
4017 -- subprograms (_Init_Proc, _Input, _Output, _Read, _Write) which do
4018 -- not freeze all entities like other bodies, but which nevertheless
4019 -- may reference entities that have to be frozen before the body and
4020 -- obviously cannot be frozen inside the body.
4022 function In_Exp_Body (N : Node_Id) return Boolean;
4023 -- Given an N_Handled_Sequence_Of_Statements node N, determines whether
4024 -- it is the handled statement sequence of an expander-generated
4025 -- subprogram (init proc, stream subprogram, or renaming as body).
4026 -- If so, this is not a freezing context.
4032 function In_Exp_Body (N : Node_Id) return Boolean is
4037 if Nkind (N) = N_Subprogram_Body then
4043 if Nkind (P) /= N_Subprogram_Body then
4047 Id := Defining_Unit_Name (Specification (P));
4049 if Nkind (Id) = N_Defining_Identifier
4050 and then (Is_Init_Proc (Id) or else
4051 Is_TSS (Id, TSS_Stream_Input) or else
4052 Is_TSS (Id, TSS_Stream_Output) or else
4053 Is_TSS (Id, TSS_Stream_Read) or else
4054 Is_TSS (Id, TSS_Stream_Write) or else
4055 Nkind (Original_Node (P)) =
4056 N_Subprogram_Renaming_Declaration)
4065 -- Start of processing for Freeze_Expression
4068 -- Immediate return if freezing is inhibited. This flag is set by the
4069 -- analyzer to stop freezing on generated expressions that would cause
4070 -- freezing if they were in the source program, but which are not
4071 -- supposed to freeze, since they are created.
4073 if Must_Not_Freeze (N) then
4077 -- If expression is non-static, then it does not freeze in a default
4078 -- expression, see section "Handling of Default Expressions" in the
4079 -- spec of package Sem for further details. Note that we have to
4080 -- make sure that we actually have a real expression (if we have
4081 -- a subtype indication, we can't test Is_Static_Expression!)
4084 and then Nkind (N) in N_Subexpr
4085 and then not Is_Static_Expression (N)
4090 -- Freeze type of expression if not frozen already
4094 if Nkind (N) in N_Has_Etype then
4095 if not Is_Frozen (Etype (N)) then
4098 -- Base type may be an derived numeric type that is frozen at
4099 -- the point of declaration, but first_subtype is still unfrozen.
4101 elsif not Is_Frozen (First_Subtype (Etype (N))) then
4102 Typ := First_Subtype (Etype (N));
4106 -- For entity name, freeze entity if not frozen already. A special
4107 -- exception occurs for an identifier that did not come from source.
4108 -- We don't let such identifiers freeze a non-internal entity, i.e.
4109 -- an entity that did come from source, since such an identifier was
4110 -- generated by the expander, and cannot have any semantic effect on
4111 -- the freezing semantics. For example, this stops the parameter of
4112 -- an initialization procedure from freezing the variable.
4114 if Is_Entity_Name (N)
4115 and then not Is_Frozen (Entity (N))
4116 and then (Nkind (N) /= N_Identifier
4117 or else Comes_From_Source (N)
4118 or else not Comes_From_Source (Entity (N)))
4125 -- For an allocator freeze designated type if not frozen already
4127 -- For an aggregate whose component type is an access type, freeze the
4128 -- designated type now, so that its freeze does not appear within the
4129 -- loop that might be created in the expansion of the aggregate. If the
4130 -- designated type is a private type without full view, the expression
4131 -- cannot contain an allocator, so the type is not frozen.
4133 -- For a function, we freeze the entity when the subprogram declaration
4134 -- is frozen, but a function call may appear in an initialization proc.
4135 -- before the declaration is frozen. We need to generate the extra
4136 -- formals, if any, to ensure that the expansion of the call includes
4137 -- the proper actuals. This only applies to Ada subprograms, not to
4144 Desig_Typ := Designated_Type (Etype (N));
4147 if Is_Array_Type (Etype (N))
4148 and then Is_Access_Type (Component_Type (Etype (N)))
4150 Desig_Typ := Designated_Type (Component_Type (Etype (N)));
4153 when N_Selected_Component |
4154 N_Indexed_Component |
4157 if Is_Access_Type (Etype (Prefix (N))) then
4158 Desig_Typ := Designated_Type (Etype (Prefix (N)));
4161 when N_Identifier =>
4163 and then Ekind (Nam) = E_Function
4164 and then Nkind (Parent (N)) = N_Function_Call
4165 and then Convention (Nam) = Convention_Ada
4167 Create_Extra_Formals (Nam);
4174 if Desig_Typ /= Empty
4175 and then (Is_Frozen (Desig_Typ)
4176 or else (not Is_Fully_Defined (Desig_Typ)))
4181 -- All done if nothing needs freezing
4185 and then No (Desig_Typ)
4190 -- Loop for looking at the right place to insert the freeze nodes,
4191 -- exiting from the loop when it is appropriate to insert the freeze
4192 -- node before the current node P.
4194 -- Also checks some special exceptions to the freezing rules. These
4195 -- cases result in a direct return, bypassing the freeze action.
4199 Parent_P := Parent (P);
4201 -- If we don't have a parent, then we are not in a well-formed tree.
4202 -- This is an unusual case, but there are some legitimate situations
4203 -- in which this occurs, notably when the expressions in the range of
4204 -- a type declaration are resolved. We simply ignore the freeze
4205 -- request in this case. Is this right ???
4207 if No (Parent_P) then
4211 -- See if we have got to an appropriate point in the tree
4213 case Nkind (Parent_P) is
4215 -- A special test for the exception of (RM 13.14(8)) for the case
4216 -- of per-object expressions (RM 3.8(18)) occurring in component
4217 -- definition or a discrete subtype definition. Note that we test
4218 -- for a component declaration which includes both cases we are
4219 -- interested in, and furthermore the tree does not have explicit
4220 -- nodes for either of these two constructs.
4222 when N_Component_Declaration =>
4224 -- The case we want to test for here is an identifier that is
4225 -- a per-object expression, this is either a discriminant that
4226 -- appears in a context other than the component declaration
4227 -- or it is a reference to the type of the enclosing construct.
4229 -- For either of these cases, we skip the freezing
4231 if not In_Spec_Expression
4232 and then Nkind (N) = N_Identifier
4233 and then (Present (Entity (N)))
4235 -- We recognize the discriminant case by just looking for
4236 -- a reference to a discriminant. It can only be one for
4237 -- the enclosing construct. Skip freezing in this case.
4239 if Ekind (Entity (N)) = E_Discriminant then
4242 -- For the case of a reference to the enclosing record,
4243 -- (or task or protected type), we look for a type that
4244 -- matches the current scope.
4246 elsif Entity (N) = Current_Scope then
4251 -- If we have an enumeration literal that appears as the choice in
4252 -- the aggregate of an enumeration representation clause, then
4253 -- freezing does not occur (RM 13.14(10)).
4255 when N_Enumeration_Representation_Clause =>
4257 -- The case we are looking for is an enumeration literal
4259 if (Nkind (N) = N_Identifier or Nkind (N) = N_Character_Literal)
4260 and then Is_Enumeration_Type (Etype (N))
4262 -- If enumeration literal appears directly as the choice,
4263 -- do not freeze (this is the normal non-overloaded case)
4265 if Nkind (Parent (N)) = N_Component_Association
4266 and then First (Choices (Parent (N))) = N
4270 -- If enumeration literal appears as the name of function
4271 -- which is the choice, then also do not freeze. This
4272 -- happens in the overloaded literal case, where the
4273 -- enumeration literal is temporarily changed to a function
4274 -- call for overloading analysis purposes.
4276 elsif Nkind (Parent (N)) = N_Function_Call
4278 Nkind (Parent (Parent (N))) = N_Component_Association
4280 First (Choices (Parent (Parent (N)))) = Parent (N)
4286 -- Normally if the parent is a handled sequence of statements,
4287 -- then the current node must be a statement, and that is an
4288 -- appropriate place to insert a freeze node.
4290 when N_Handled_Sequence_Of_Statements =>
4292 -- An exception occurs when the sequence of statements is for
4293 -- an expander generated body that did not do the usual freeze
4294 -- all operation. In this case we usually want to freeze
4295 -- outside this body, not inside it, and we skip past the
4296 -- subprogram body that we are inside.
4298 if In_Exp_Body (Parent_P) then
4300 -- However, we *do* want to freeze at this point if we have
4301 -- an entity to freeze, and that entity is declared *inside*
4302 -- the body of the expander generated procedure. This case
4303 -- is recognized by the scope of the type, which is either
4304 -- the spec for some enclosing body, or (in the case of
4305 -- init_procs, for which there are no separate specs) the
4309 Subp : constant Node_Id := Parent (Parent_P);
4313 if Nkind (Subp) = N_Subprogram_Body then
4314 Cspc := Corresponding_Spec (Subp);
4316 if (Present (Typ) and then Scope (Typ) = Cspc)
4318 (Present (Nam) and then Scope (Nam) = Cspc)
4323 and then Scope (Typ) = Current_Scope
4324 and then Current_Scope = Defining_Entity (Subp)
4331 -- If not that exception to the exception, then this is
4332 -- where we delay the freeze till outside the body.
4334 Parent_P := Parent (Parent_P);
4335 Freeze_Outside := True;
4337 -- Here if normal case where we are in handled statement
4338 -- sequence and want to do the insertion right there.
4344 -- If parent is a body or a spec or a block, then the current node
4345 -- is a statement or declaration and we can insert the freeze node
4348 when N_Package_Specification |
4354 N_Block_Statement => exit;
4356 -- The expander is allowed to define types in any statements list,
4357 -- so any of the following parent nodes also mark a freezing point
4358 -- if the actual node is in a list of statements or declarations.
4360 when N_Exception_Handler |
4363 N_Case_Statement_Alternative |
4364 N_Compilation_Unit_Aux |
4365 N_Selective_Accept |
4366 N_Accept_Alternative |
4367 N_Delay_Alternative |
4368 N_Conditional_Entry_Call |
4369 N_Entry_Call_Alternative |
4370 N_Triggering_Alternative |
4376 exit when Is_List_Member (P);
4378 -- Note: The N_Loop_Statement is a special case. A type that
4379 -- appears in the source can never be frozen in a loop (this
4380 -- occurs only because of a loop expanded by the expander), so we
4381 -- keep on going. Otherwise we terminate the search. Same is true
4382 -- of any entity which comes from source. (if they have predefined
4383 -- type, that type does not appear to come from source, but the
4384 -- entity should not be frozen here).
4386 when N_Loop_Statement =>
4387 exit when not Comes_From_Source (Etype (N))
4388 and then (No (Nam) or else not Comes_From_Source (Nam));
4390 -- For all other cases, keep looking at parents
4396 -- We fall through the case if we did not yet find the proper
4397 -- place in the free for inserting the freeze node, so climb!
4402 -- If the expression appears in a record or an initialization procedure,
4403 -- the freeze nodes are collected and attached to the current scope, to
4404 -- be inserted and analyzed on exit from the scope, to insure that
4405 -- generated entities appear in the correct scope. If the expression is
4406 -- a default for a discriminant specification, the scope is still void.
4407 -- The expression can also appear in the discriminant part of a private
4408 -- or concurrent type.
4410 -- If the expression appears in a constrained subcomponent of an
4411 -- enclosing record declaration, the freeze nodes must be attached to
4412 -- the outer record type so they can eventually be placed in the
4413 -- enclosing declaration list.
4415 -- The other case requiring this special handling is if we are in a
4416 -- default expression, since in that case we are about to freeze a
4417 -- static type, and the freeze scope needs to be the outer scope, not
4418 -- the scope of the subprogram with the default parameter.
4420 -- For default expressions and other spec expressions in generic units,
4421 -- the Move_Freeze_Nodes mechanism (see sem_ch12.adb) takes care of
4422 -- placing them at the proper place, after the generic unit.
4424 if (In_Spec_Exp and not Inside_A_Generic)
4425 or else Freeze_Outside
4426 or else (Is_Type (Current_Scope)
4427 and then (not Is_Concurrent_Type (Current_Scope)
4428 or else not Has_Completion (Current_Scope)))
4429 or else Ekind (Current_Scope) = E_Void
4432 Loc : constant Source_Ptr := Sloc (Current_Scope);
4433 Freeze_Nodes : List_Id := No_List;
4434 Pos : Int := Scope_Stack.Last;
4437 if Present (Desig_Typ) then
4438 Freeze_And_Append (Desig_Typ, Loc, Freeze_Nodes);
4441 if Present (Typ) then
4442 Freeze_And_Append (Typ, Loc, Freeze_Nodes);
4445 if Present (Nam) then
4446 Freeze_And_Append (Nam, Loc, Freeze_Nodes);
4449 -- The current scope may be that of a constrained component of
4450 -- an enclosing record declaration, which is above the current
4451 -- scope in the scope stack.
4453 if Is_Record_Type (Scope (Current_Scope)) then
4457 if Is_Non_Empty_List (Freeze_Nodes) then
4458 if No (Scope_Stack.Table (Pos).Pending_Freeze_Actions) then
4459 Scope_Stack.Table (Pos).Pending_Freeze_Actions :=
4462 Append_List (Freeze_Nodes, Scope_Stack.Table
4463 (Pos).Pending_Freeze_Actions);
4471 -- Now we have the right place to do the freezing. First, a special
4472 -- adjustment, if we are in spec-expression analysis mode, these freeze
4473 -- actions must not be thrown away (normally all inserted actions are
4474 -- thrown away in this mode. However, the freeze actions are from static
4475 -- expressions and one of the important reasons we are doing this
4476 -- special analysis is to get these freeze actions. Therefore we turn
4477 -- off the In_Spec_Expression mode to propagate these freeze actions.
4478 -- This also means they get properly analyzed and expanded.
4480 In_Spec_Expression := False;
4482 -- Freeze the designated type of an allocator (RM 13.14(13))
4484 if Present (Desig_Typ) then
4485 Freeze_Before (P, Desig_Typ);
4488 -- Freeze type of expression (RM 13.14(10)). Note that we took care of
4489 -- the enumeration representation clause exception in the loop above.
4491 if Present (Typ) then
4492 Freeze_Before (P, Typ);
4495 -- Freeze name if one is present (RM 13.14(11))
4497 if Present (Nam) then
4498 Freeze_Before (P, Nam);
4501 -- Restore In_Spec_Expression flag
4503 In_Spec_Expression := In_Spec_Exp;
4504 end Freeze_Expression;
4506 -----------------------------
4507 -- Freeze_Fixed_Point_Type --
4508 -----------------------------
4510 -- Certain fixed-point types and subtypes, including implicit base types
4511 -- and declared first subtypes, have not yet set up a range. This is
4512 -- because the range cannot be set until the Small and Size values are
4513 -- known, and these are not known till the type is frozen.
4515 -- To signal this case, Scalar_Range contains an unanalyzed syntactic range
4516 -- whose bounds are unanalyzed real literals. This routine will recognize
4517 -- this case, and transform this range node into a properly typed range
4518 -- with properly analyzed and resolved values.
4520 procedure Freeze_Fixed_Point_Type (Typ : Entity_Id) is
4521 Rng : constant Node_Id := Scalar_Range (Typ);
4522 Lo : constant Node_Id := Low_Bound (Rng);
4523 Hi : constant Node_Id := High_Bound (Rng);
4524 Btyp : constant Entity_Id := Base_Type (Typ);
4525 Brng : constant Node_Id := Scalar_Range (Btyp);
4526 BLo : constant Node_Id := Low_Bound (Brng);
4527 BHi : constant Node_Id := High_Bound (Brng);
4528 Small : constant Ureal := Small_Value (Typ);
4535 function Fsize (Lov, Hiv : Ureal) return Nat;
4536 -- Returns size of type with given bounds. Also leaves these
4537 -- bounds set as the current bounds of the Typ.
4543 function Fsize (Lov, Hiv : Ureal) return Nat is
4545 Set_Realval (Lo, Lov);
4546 Set_Realval (Hi, Hiv);
4547 return Minimum_Size (Typ);
4550 -- Start of processing for Freeze_Fixed_Point_Type
4553 -- If Esize of a subtype has not previously been set, set it now
4555 if Unknown_Esize (Typ) then
4556 Atype := Ancestor_Subtype (Typ);
4558 if Present (Atype) then
4559 Set_Esize (Typ, Esize (Atype));
4561 Set_Esize (Typ, Esize (Base_Type (Typ)));
4565 -- Immediate return if the range is already analyzed. This means that
4566 -- the range is already set, and does not need to be computed by this
4569 if Analyzed (Rng) then
4573 -- Immediate return if either of the bounds raises Constraint_Error
4575 if Raises_Constraint_Error (Lo)
4576 or else Raises_Constraint_Error (Hi)
4581 Loval := Realval (Lo);
4582 Hival := Realval (Hi);
4584 -- Ordinary fixed-point case
4586 if Is_Ordinary_Fixed_Point_Type (Typ) then
4588 -- For the ordinary fixed-point case, we are allowed to fudge the
4589 -- end-points up or down by small. Generally we prefer to fudge up,
4590 -- i.e. widen the bounds for non-model numbers so that the end points
4591 -- are included. However there are cases in which this cannot be
4592 -- done, and indeed cases in which we may need to narrow the bounds.
4593 -- The following circuit makes the decision.
4595 -- Note: our terminology here is that Incl_EP means that the bounds
4596 -- are widened by Small if necessary to include the end points, and
4597 -- Excl_EP means that the bounds are narrowed by Small to exclude the
4598 -- end-points if this reduces the size.
4600 -- Note that in the Incl case, all we care about is including the
4601 -- end-points. In the Excl case, we want to narrow the bounds as
4602 -- much as permitted by the RM, to give the smallest possible size.
4605 Loval_Incl_EP : Ureal;
4606 Hival_Incl_EP : Ureal;
4608 Loval_Excl_EP : Ureal;
4609 Hival_Excl_EP : Ureal;
4615 First_Subt : Entity_Id;
4620 -- First step. Base types are required to be symmetrical. Right
4621 -- now, the base type range is a copy of the first subtype range.
4622 -- This will be corrected before we are done, but right away we
4623 -- need to deal with the case where both bounds are non-negative.
4624 -- In this case, we set the low bound to the negative of the high
4625 -- bound, to make sure that the size is computed to include the
4626 -- required sign. Note that we do not need to worry about the
4627 -- case of both bounds negative, because the sign will be dealt
4628 -- with anyway. Furthermore we can't just go making such a bound
4629 -- symmetrical, since in a twos-complement system, there is an
4630 -- extra negative value which could not be accommodated on the
4634 and then not UR_Is_Negative (Loval)
4635 and then Hival > Loval
4638 Set_Realval (Lo, Loval);
4641 -- Compute the fudged bounds. If the number is a model number,
4642 -- then we do nothing to include it, but we are allowed to backoff
4643 -- to the next adjacent model number when we exclude it. If it is
4644 -- not a model number then we straddle the two values with the
4645 -- model numbers on either side.
4647 Model_Num := UR_Trunc (Loval / Small) * Small;
4649 if Loval = Model_Num then
4650 Loval_Incl_EP := Model_Num;
4652 Loval_Incl_EP := Model_Num - Small;
4655 -- The low value excluding the end point is Small greater, but
4656 -- we do not do this exclusion if the low value is positive,
4657 -- since it can't help the size and could actually hurt by
4658 -- crossing the high bound.
4660 if UR_Is_Negative (Loval_Incl_EP) then
4661 Loval_Excl_EP := Loval_Incl_EP + Small;
4663 -- If the value went from negative to zero, then we have the
4664 -- case where Loval_Incl_EP is the model number just below
4665 -- zero, so we want to stick to the negative value for the
4666 -- base type to maintain the condition that the size will
4667 -- include signed values.
4670 and then UR_Is_Zero (Loval_Excl_EP)
4672 Loval_Excl_EP := Loval_Incl_EP;
4676 Loval_Excl_EP := Loval_Incl_EP;
4679 -- Similar processing for upper bound and high value
4681 Model_Num := UR_Trunc (Hival / Small) * Small;
4683 if Hival = Model_Num then
4684 Hival_Incl_EP := Model_Num;
4686 Hival_Incl_EP := Model_Num + Small;
4689 if UR_Is_Positive (Hival_Incl_EP) then
4690 Hival_Excl_EP := Hival_Incl_EP - Small;
4692 Hival_Excl_EP := Hival_Incl_EP;
4695 -- One further adjustment is needed. In the case of subtypes, we
4696 -- cannot go outside the range of the base type, or we get
4697 -- peculiarities, and the base type range is already set. This
4698 -- only applies to the Incl values, since clearly the Excl values
4699 -- are already as restricted as they are allowed to be.
4702 Loval_Incl_EP := UR_Max (Loval_Incl_EP, Realval (BLo));
4703 Hival_Incl_EP := UR_Min (Hival_Incl_EP, Realval (BHi));
4706 -- Get size including and excluding end points
4708 Size_Incl_EP := Fsize (Loval_Incl_EP, Hival_Incl_EP);
4709 Size_Excl_EP := Fsize (Loval_Excl_EP, Hival_Excl_EP);
4711 -- No need to exclude end-points if it does not reduce size
4713 if Fsize (Loval_Incl_EP, Hival_Excl_EP) = Size_Excl_EP then
4714 Loval_Excl_EP := Loval_Incl_EP;
4717 if Fsize (Loval_Excl_EP, Hival_Incl_EP) = Size_Excl_EP then
4718 Hival_Excl_EP := Hival_Incl_EP;
4721 -- Now we set the actual size to be used. We want to use the
4722 -- bounds fudged up to include the end-points but only if this
4723 -- can be done without violating a specifically given size
4724 -- size clause or causing an unacceptable increase in size.
4726 -- Case of size clause given
4728 if Has_Size_Clause (Typ) then
4730 -- Use the inclusive size only if it is consistent with
4731 -- the explicitly specified size.
4733 if Size_Incl_EP <= RM_Size (Typ) then
4734 Actual_Lo := Loval_Incl_EP;
4735 Actual_Hi := Hival_Incl_EP;
4736 Actual_Size := Size_Incl_EP;
4738 -- If the inclusive size is too large, we try excluding
4739 -- the end-points (will be caught later if does not work).
4742 Actual_Lo := Loval_Excl_EP;
4743 Actual_Hi := Hival_Excl_EP;
4744 Actual_Size := Size_Excl_EP;
4747 -- Case of size clause not given
4750 -- If we have a base type whose corresponding first subtype
4751 -- has an explicit size that is large enough to include our
4752 -- end-points, then do so. There is no point in working hard
4753 -- to get a base type whose size is smaller than the specified
4754 -- size of the first subtype.
4756 First_Subt := First_Subtype (Typ);
4758 if Has_Size_Clause (First_Subt)
4759 and then Size_Incl_EP <= Esize (First_Subt)
4761 Actual_Size := Size_Incl_EP;
4762 Actual_Lo := Loval_Incl_EP;
4763 Actual_Hi := Hival_Incl_EP;
4765 -- If excluding the end-points makes the size smaller and
4766 -- results in a size of 8,16,32,64, then we take the smaller
4767 -- size. For the 64 case, this is compulsory. For the other
4768 -- cases, it seems reasonable. We like to include end points
4769 -- if we can, but not at the expense of moving to the next
4770 -- natural boundary of size.
4772 elsif Size_Incl_EP /= Size_Excl_EP
4774 (Size_Excl_EP = 8 or else
4775 Size_Excl_EP = 16 or else
4776 Size_Excl_EP = 32 or else
4779 Actual_Size := Size_Excl_EP;
4780 Actual_Lo := Loval_Excl_EP;
4781 Actual_Hi := Hival_Excl_EP;
4783 -- Otherwise we can definitely include the end points
4786 Actual_Size := Size_Incl_EP;
4787 Actual_Lo := Loval_Incl_EP;
4788 Actual_Hi := Hival_Incl_EP;
4791 -- One pathological case: normally we never fudge a low bound
4792 -- down, since it would seem to increase the size (if it has
4793 -- any effect), but for ranges containing single value, or no
4794 -- values, the high bound can be small too large. Consider:
4796 -- type t is delta 2.0**(-14)
4797 -- range 131072.0 .. 0;
4799 -- That lower bound is *just* outside the range of 32 bits, and
4800 -- does need fudging down in this case. Note that the bounds
4801 -- will always have crossed here, since the high bound will be
4802 -- fudged down if necessary, as in the case of:
4804 -- type t is delta 2.0**(-14)
4805 -- range 131072.0 .. 131072.0;
4807 -- So we detect the situation by looking for crossed bounds,
4808 -- and if the bounds are crossed, and the low bound is greater
4809 -- than zero, we will always back it off by small, since this
4810 -- is completely harmless.
4812 if Actual_Lo > Actual_Hi then
4813 if UR_Is_Positive (Actual_Lo) then
4814 Actual_Lo := Loval_Incl_EP - Small;
4815 Actual_Size := Fsize (Actual_Lo, Actual_Hi);
4817 -- And of course, we need to do exactly the same parallel
4818 -- fudge for flat ranges in the negative region.
4820 elsif UR_Is_Negative (Actual_Hi) then
4821 Actual_Hi := Hival_Incl_EP + Small;
4822 Actual_Size := Fsize (Actual_Lo, Actual_Hi);
4827 Set_Realval (Lo, Actual_Lo);
4828 Set_Realval (Hi, Actual_Hi);
4831 -- For the decimal case, none of this fudging is required, since there
4832 -- are no end-point problems in the decimal case (the end-points are
4833 -- always included).
4836 Actual_Size := Fsize (Loval, Hival);
4839 -- At this stage, the actual size has been calculated and the proper
4840 -- required bounds are stored in the low and high bounds.
4842 if Actual_Size > 64 then
4843 Error_Msg_Uint_1 := UI_From_Int (Actual_Size);
4845 ("size required (^) for type& too large, maximum allowed is 64",
4850 -- Check size against explicit given size
4852 if Has_Size_Clause (Typ) then
4853 if Actual_Size > RM_Size (Typ) then
4854 Error_Msg_Uint_1 := RM_Size (Typ);
4855 Error_Msg_Uint_2 := UI_From_Int (Actual_Size);
4857 ("size given (^) for type& too small, minimum allowed is ^",
4858 Size_Clause (Typ), Typ);
4861 Actual_Size := UI_To_Int (Esize (Typ));
4864 -- Increase size to next natural boundary if no size clause given
4867 if Actual_Size <= 8 then
4869 elsif Actual_Size <= 16 then
4871 elsif Actual_Size <= 32 then
4877 Init_Esize (Typ, Actual_Size);
4878 Adjust_Esize_For_Alignment (Typ);
4881 -- If we have a base type, then expand the bounds so that they extend to
4882 -- the full width of the allocated size in bits, to avoid junk range
4883 -- checks on intermediate computations.
4885 if Base_Type (Typ) = Typ then
4886 Set_Realval (Lo, -(Small * (Uint_2 ** (Actual_Size - 1))));
4887 Set_Realval (Hi, (Small * (Uint_2 ** (Actual_Size - 1) - 1)));
4890 -- Final step is to reanalyze the bounds using the proper type
4891 -- and set the Corresponding_Integer_Value fields of the literals.
4893 Set_Etype (Lo, Empty);
4894 Set_Analyzed (Lo, False);
4897 -- Resolve with universal fixed if the base type, and the base type if
4898 -- it is a subtype. Note we can't resolve the base type with itself,
4899 -- that would be a reference before definition.
4902 Resolve (Lo, Universal_Fixed);
4907 -- Set corresponding integer value for bound
4909 Set_Corresponding_Integer_Value
4910 (Lo, UR_To_Uint (Realval (Lo) / Small));
4912 -- Similar processing for high bound
4914 Set_Etype (Hi, Empty);
4915 Set_Analyzed (Hi, False);
4919 Resolve (Hi, Universal_Fixed);
4924 Set_Corresponding_Integer_Value
4925 (Hi, UR_To_Uint (Realval (Hi) / Small));
4927 -- Set type of range to correspond to bounds
4929 Set_Etype (Rng, Etype (Lo));
4931 -- Set Esize to calculated size if not set already
4933 if Unknown_Esize (Typ) then
4934 Init_Esize (Typ, Actual_Size);
4937 -- Set RM_Size if not already set. If already set, check value
4940 Minsiz : constant Uint := UI_From_Int (Minimum_Size (Typ));
4943 if RM_Size (Typ) /= Uint_0 then
4944 if RM_Size (Typ) < Minsiz then
4945 Error_Msg_Uint_1 := RM_Size (Typ);
4946 Error_Msg_Uint_2 := Minsiz;
4948 ("size given (^) for type& too small, minimum allowed is ^",
4949 Size_Clause (Typ), Typ);
4953 Set_RM_Size (Typ, Minsiz);
4956 end Freeze_Fixed_Point_Type;
4962 procedure Freeze_Itype (T : Entity_Id; N : Node_Id) is
4966 Set_Has_Delayed_Freeze (T);
4967 L := Freeze_Entity (T, Sloc (N));
4969 if Is_Non_Empty_List (L) then
4970 Insert_Actions (N, L);
4974 --------------------------
4975 -- Freeze_Static_Object --
4976 --------------------------
4978 procedure Freeze_Static_Object (E : Entity_Id) is
4980 Cannot_Be_Static : exception;
4981 -- Exception raised if the type of a static object cannot be made
4982 -- static. This happens if the type depends on non-global objects.
4984 procedure Ensure_Expression_Is_SA (N : Node_Id);
4985 -- Called to ensure that an expression used as part of a type definition
4986 -- is statically allocatable, which means that the expression type is
4987 -- statically allocatable, and the expression is either static, or a
4988 -- reference to a library level constant.
4990 procedure Ensure_Type_Is_SA (Typ : Entity_Id);
4991 -- Called to mark a type as static, checking that it is possible
4992 -- to set the type as static. If it is not possible, then the
4993 -- exception Cannot_Be_Static is raised.
4995 -----------------------------
4996 -- Ensure_Expression_Is_SA --
4997 -----------------------------
4999 procedure Ensure_Expression_Is_SA (N : Node_Id) is
5003 Ensure_Type_Is_SA (Etype (N));
5005 if Is_Static_Expression (N) then
5008 elsif Nkind (N) = N_Identifier then
5012 and then Ekind (Ent) = E_Constant
5013 and then Is_Library_Level_Entity (Ent)
5019 raise Cannot_Be_Static;
5020 end Ensure_Expression_Is_SA;
5022 -----------------------
5023 -- Ensure_Type_Is_SA --
5024 -----------------------
5026 procedure Ensure_Type_Is_SA (Typ : Entity_Id) is
5031 -- If type is library level, we are all set
5033 if Is_Library_Level_Entity (Typ) then
5037 -- We are also OK if the type already marked as statically allocated,
5038 -- which means we processed it before.
5040 if Is_Statically_Allocated (Typ) then
5044 -- Mark type as statically allocated
5046 Set_Is_Statically_Allocated (Typ);
5048 -- Check that it is safe to statically allocate this type
5050 if Is_Scalar_Type (Typ) or else Is_Real_Type (Typ) then
5051 Ensure_Expression_Is_SA (Type_Low_Bound (Typ));
5052 Ensure_Expression_Is_SA (Type_High_Bound (Typ));
5054 elsif Is_Array_Type (Typ) then
5055 N := First_Index (Typ);
5056 while Present (N) loop
5057 Ensure_Type_Is_SA (Etype (N));
5061 Ensure_Type_Is_SA (Component_Type (Typ));
5063 elsif Is_Access_Type (Typ) then
5064 if Ekind (Designated_Type (Typ)) = E_Subprogram_Type then
5068 T : constant Entity_Id := Etype (Designated_Type (Typ));
5071 if T /= Standard_Void_Type then
5072 Ensure_Type_Is_SA (T);
5075 F := First_Formal (Designated_Type (Typ));
5077 while Present (F) loop
5078 Ensure_Type_Is_SA (Etype (F));
5084 Ensure_Type_Is_SA (Designated_Type (Typ));
5087 elsif Is_Record_Type (Typ) then
5088 C := First_Entity (Typ);
5089 while Present (C) loop
5090 if Ekind (C) = E_Discriminant
5091 or else Ekind (C) = E_Component
5093 Ensure_Type_Is_SA (Etype (C));
5095 elsif Is_Type (C) then
5096 Ensure_Type_Is_SA (C);
5102 elsif Ekind (Typ) = E_Subprogram_Type then
5103 Ensure_Type_Is_SA (Etype (Typ));
5105 C := First_Formal (Typ);
5106 while Present (C) loop
5107 Ensure_Type_Is_SA (Etype (C));
5112 raise Cannot_Be_Static;
5114 end Ensure_Type_Is_SA;
5116 -- Start of processing for Freeze_Static_Object
5119 Ensure_Type_Is_SA (Etype (E));
5122 when Cannot_Be_Static =>
5124 -- If the object that cannot be static is imported or exported, then
5125 -- issue an error message saying that this object cannot be imported
5126 -- or exported. If it has an address clause it is an overlay in the
5127 -- current partition and the static requirement is not relevant.
5129 if Is_Imported (E) and then No (Address_Clause (E)) then
5131 ("& cannot be imported (local type is not constant)", E);
5133 -- Otherwise must be exported, something is wrong if compiler
5134 -- is marking something as statically allocated which cannot be).
5136 else pragma Assert (Is_Exported (E));
5138 ("& cannot be exported (local type is not constant)", E);
5140 end Freeze_Static_Object;
5142 -----------------------
5143 -- Freeze_Subprogram --
5144 -----------------------
5146 procedure Freeze_Subprogram (E : Entity_Id) is
5151 -- Subprogram may not have an address clause unless it is imported
5153 if Present (Address_Clause (E)) then
5154 if not Is_Imported (E) then
5156 ("address clause can only be given " &
5157 "for imported subprogram",
5158 Name (Address_Clause (E)));
5162 -- Reset the Pure indication on an imported subprogram unless an
5163 -- explicit Pure_Function pragma was present. We do this because
5164 -- otherwise it is an insidious error to call a non-pure function from
5165 -- pure unit and have calls mysteriously optimized away. What happens
5166 -- here is that the Import can bypass the normal check to ensure that
5167 -- pure units call only pure subprograms.
5170 and then Is_Pure (E)
5171 and then not Has_Pragma_Pure_Function (E)
5173 Set_Is_Pure (E, False);
5176 -- For non-foreign convention subprograms, this is where we create
5177 -- the extra formals (for accessibility level and constrained bit
5178 -- information). We delay this till the freeze point precisely so
5179 -- that we know the convention!
5181 if not Has_Foreign_Convention (E) then
5182 Create_Extra_Formals (E);
5185 -- If this is convention Ada and a Valued_Procedure, that's odd
5187 if Ekind (E) = E_Procedure
5188 and then Is_Valued_Procedure (E)
5189 and then Convention (E) = Convention_Ada
5190 and then Warn_On_Export_Import
5193 ("?Valued_Procedure has no effect for convention Ada", E);
5194 Set_Is_Valued_Procedure (E, False);
5197 -- Case of foreign convention
5202 -- For foreign conventions, warn about return of an
5203 -- unconstrained array.
5205 -- Note: we *do* allow a return by descriptor for the VMS case,
5206 -- though here there is probably more to be done ???
5208 if Ekind (E) = E_Function then
5209 Retype := Underlying_Type (Etype (E));
5211 -- If no return type, probably some other error, e.g. a
5212 -- missing full declaration, so ignore.
5217 -- If the return type is generic, we have emitted a warning
5218 -- earlier on, and there is nothing else to check here. Specific
5219 -- instantiations may lead to erroneous behavior.
5221 elsif Is_Generic_Type (Etype (E)) then
5224 -- Display warning if returning unconstrained array
5226 elsif Is_Array_Type (Retype)
5227 and then not Is_Constrained (Retype)
5229 -- Exclude cases where descriptor mechanism is set, since the
5230 -- VMS descriptor mechanisms allow such unconstrained returns.
5232 and then Mechanism (E) not in Descriptor_Codes
5234 -- Check appropriate warning is enabled (should we check for
5235 -- Warnings (Off) on specific entities here, probably so???)
5237 and then Warn_On_Export_Import
5239 -- Exclude the VM case, since return of unconstrained arrays
5240 -- is properly handled in both the JVM and .NET cases.
5242 and then VM_Target = No_VM
5245 ("?foreign convention function& should not return " &
5246 "unconstrained array", E);
5251 -- If any of the formals for an exported foreign convention
5252 -- subprogram have defaults, then emit an appropriate warning since
5253 -- this is odd (default cannot be used from non-Ada code)
5255 if Is_Exported (E) then
5256 F := First_Formal (E);
5257 while Present (F) loop
5258 if Warn_On_Export_Import
5259 and then Present (Default_Value (F))
5262 ("?parameter cannot be defaulted in non-Ada call",
5271 -- For VMS, descriptor mechanisms for parameters are allowed only for
5272 -- imported/exported subprograms. Moreover, the NCA descriptor is not
5273 -- allowed for parameters of exported subprograms.
5275 if OpenVMS_On_Target then
5276 if Is_Exported (E) then
5277 F := First_Formal (E);
5278 while Present (F) loop
5279 if Mechanism (F) = By_Descriptor_NCA then
5281 ("'N'C'A' descriptor for parameter not permitted", F);
5283 ("\can only be used for imported subprogram", F);
5289 elsif not Is_Imported (E) then
5290 F := First_Formal (E);
5291 while Present (F) loop
5292 if Mechanism (F) in Descriptor_Codes then
5294 ("descriptor mechanism for parameter not permitted", F);
5296 ("\can only be used for imported/exported subprogram", F);
5304 -- Pragma Inline_Always is disallowed for dispatching subprograms
5305 -- because the address of such subprograms is saved in the dispatch
5306 -- table to support dispatching calls, and dispatching calls cannot
5307 -- be inlined. This is consistent with the restriction against using
5308 -- 'Access or 'Address on an Inline_Always subprogram.
5310 if Is_Dispatching_Operation (E)
5311 and then Has_Pragma_Inline_Always (E)
5314 ("pragma Inline_Always not allowed for dispatching subprograms", E);
5317 -- Because of the implicit representation of inherited predefined
5318 -- operators in the front-end, the overriding status of the operation
5319 -- may be affected when a full view of a type is analyzed, and this is
5320 -- not captured by the analysis of the corresponding type declaration.
5321 -- Therefore the correctness of a not-overriding indicator must be
5322 -- rechecked when the subprogram is frozen.
5324 if Nkind (E) = N_Defining_Operator_Symbol
5325 and then not Error_Posted (Parent (E))
5327 Check_Overriding_Indicator (E, Empty, Is_Primitive (E));
5329 end Freeze_Subprogram;
5331 ----------------------
5332 -- Is_Fully_Defined --
5333 ----------------------
5335 function Is_Fully_Defined (T : Entity_Id) return Boolean is
5337 if Ekind (T) = E_Class_Wide_Type then
5338 return Is_Fully_Defined (Etype (T));
5340 elsif Is_Array_Type (T) then
5341 return Is_Fully_Defined (Component_Type (T));
5343 elsif Is_Record_Type (T)
5344 and not Is_Private_Type (T)
5346 -- Verify that the record type has no components with private types
5347 -- without completion.
5353 Comp := First_Component (T);
5355 while Present (Comp) loop
5356 if not Is_Fully_Defined (Etype (Comp)) then
5360 Next_Component (Comp);
5365 -- For the designated type of an access to subprogram, all types in
5366 -- the profile must be fully defined.
5368 elsif Ekind (T) = E_Subprogram_Type then
5373 F := First_Formal (T);
5374 while Present (F) loop
5375 if not Is_Fully_Defined (Etype (F)) then
5382 return Is_Fully_Defined (Etype (T));
5386 return not Is_Private_Type (T)
5387 or else Present (Full_View (Base_Type (T)));
5389 end Is_Fully_Defined;
5391 ---------------------------------
5392 -- Process_Default_Expressions --
5393 ---------------------------------
5395 procedure Process_Default_Expressions
5397 After : in out Node_Id)
5399 Loc : constant Source_Ptr := Sloc (E);
5406 Set_Default_Expressions_Processed (E);
5408 -- A subprogram instance and its associated anonymous subprogram share
5409 -- their signature. The default expression functions are defined in the
5410 -- wrapper packages for the anonymous subprogram, and should not be
5411 -- generated again for the instance.
5413 if Is_Generic_Instance (E)
5414 and then Present (Alias (E))
5415 and then Default_Expressions_Processed (Alias (E))
5420 Formal := First_Formal (E);
5421 while Present (Formal) loop
5422 if Present (Default_Value (Formal)) then
5424 -- We work with a copy of the default expression because we
5425 -- do not want to disturb the original, since this would mess
5426 -- up the conformance checking.
5428 Dcopy := New_Copy_Tree (Default_Value (Formal));
5430 -- The analysis of the expression may generate insert actions,
5431 -- which of course must not be executed. We wrap those actions
5432 -- in a procedure that is not called, and later on eliminated.
5433 -- The following cases have no side-effects, and are analyzed
5436 if Nkind (Dcopy) = N_Identifier
5437 or else Nkind (Dcopy) = N_Expanded_Name
5438 or else Nkind (Dcopy) = N_Integer_Literal
5439 or else (Nkind (Dcopy) = N_Real_Literal
5440 and then not Vax_Float (Etype (Dcopy)))
5441 or else Nkind (Dcopy) = N_Character_Literal
5442 or else Nkind (Dcopy) = N_String_Literal
5443 or else Known_Null (Dcopy)
5444 or else (Nkind (Dcopy) = N_Attribute_Reference
5446 Attribute_Name (Dcopy) = Name_Null_Parameter)
5449 -- If there is no default function, we must still do a full
5450 -- analyze call on the default value, to ensure that all error
5451 -- checks are performed, e.g. those associated with static
5452 -- evaluation. Note: this branch will always be taken if the
5453 -- analyzer is turned off (but we still need the error checks).
5455 -- Note: the setting of parent here is to meet the requirement
5456 -- that we can only analyze the expression while attached to
5457 -- the tree. Really the requirement is that the parent chain
5458 -- be set, we don't actually need to be in the tree.
5460 Set_Parent (Dcopy, Declaration_Node (Formal));
5463 -- Default expressions are resolved with their own type if the
5464 -- context is generic, to avoid anomalies with private types.
5466 if Ekind (Scope (E)) = E_Generic_Package then
5469 Resolve (Dcopy, Etype (Formal));
5472 -- If that resolved expression will raise constraint error,
5473 -- then flag the default value as raising constraint error.
5474 -- This allows a proper error message on the calls.
5476 if Raises_Constraint_Error (Dcopy) then
5477 Set_Raises_Constraint_Error (Default_Value (Formal));
5480 -- If the default is a parameterless call, we use the name of
5481 -- the called function directly, and there is no body to build.
5483 elsif Nkind (Dcopy) = N_Function_Call
5484 and then No (Parameter_Associations (Dcopy))
5488 -- Else construct and analyze the body of a wrapper procedure
5489 -- that contains an object declaration to hold the expression.
5490 -- Given that this is done only to complete the analysis, it
5491 -- simpler to build a procedure than a function which might
5492 -- involve secondary stack expansion.
5495 Dnam := Make_Temporary (Loc, 'D');
5498 Make_Subprogram_Body (Loc,
5500 Make_Procedure_Specification (Loc,
5501 Defining_Unit_Name => Dnam),
5503 Declarations => New_List (
5504 Make_Object_Declaration (Loc,
5505 Defining_Identifier =>
5506 Make_Defining_Identifier (Loc,
5507 New_Internal_Name ('T')),
5508 Object_Definition =>
5509 New_Occurrence_Of (Etype (Formal), Loc),
5510 Expression => New_Copy_Tree (Dcopy))),
5512 Handled_Statement_Sequence =>
5513 Make_Handled_Sequence_Of_Statements (Loc,
5514 Statements => New_List));
5516 Set_Scope (Dnam, Scope (E));
5517 Set_Assignment_OK (First (Declarations (Dbody)));
5518 Set_Is_Eliminated (Dnam);
5519 Insert_After (After, Dbody);
5525 Next_Formal (Formal);
5527 end Process_Default_Expressions;
5529 ----------------------------------------
5530 -- Set_Component_Alignment_If_Not_Set --
5531 ----------------------------------------
5533 procedure Set_Component_Alignment_If_Not_Set (Typ : Entity_Id) is
5535 -- Ignore if not base type, subtypes don't need anything
5537 if Typ /= Base_Type (Typ) then
5541 -- Do not override existing representation
5543 if Is_Packed (Typ) then
5546 elsif Has_Specified_Layout (Typ) then
5549 elsif Component_Alignment (Typ) /= Calign_Default then
5553 Set_Component_Alignment
5554 (Typ, Scope_Stack.Table
5555 (Scope_Stack.Last).Component_Alignment_Default);
5557 end Set_Component_Alignment_If_Not_Set;
5563 procedure Undelay_Type (T : Entity_Id) is
5565 Set_Has_Delayed_Freeze (T, False);
5566 Set_Freeze_Node (T, Empty);
5568 -- Since we don't want T to have a Freeze_Node, we don't want its
5569 -- Full_View or Corresponding_Record_Type to have one either.
5571 -- ??? Fundamentally, this whole handling is a kludge. What we really
5572 -- want is to be sure that for an Itype that's part of record R and is a
5573 -- subtype of type T, that it's frozen after the later of the freeze
5574 -- points of R and T. We have no way of doing that directly, so what we
5575 -- do is force most such Itypes to be frozen as part of freezing R via
5576 -- this procedure and only delay the ones that need to be delayed
5577 -- (mostly the designated types of access types that are defined as part
5580 if Is_Private_Type (T)
5581 and then Present (Full_View (T))
5582 and then Is_Itype (Full_View (T))
5583 and then Is_Record_Type (Scope (Full_View (T)))
5585 Undelay_Type (Full_View (T));
5588 if Is_Concurrent_Type (T)
5589 and then Present (Corresponding_Record_Type (T))
5590 and then Is_Itype (Corresponding_Record_Type (T))
5591 and then Is_Record_Type (Scope (Corresponding_Record_Type (T)))
5593 Undelay_Type (Corresponding_Record_Type (T));
5601 procedure Warn_Overlay
5606 Ent : constant Entity_Id := Entity (Nam);
5607 -- The object to which the address clause applies
5610 Old : Entity_Id := Empty;
5614 -- No warning if address clause overlay warnings are off
5616 if not Address_Clause_Overlay_Warnings then
5620 -- No warning if there is an explicit initialization
5622 Init := Original_Node (Expression (Declaration_Node (Ent)));
5624 if Present (Init) and then Comes_From_Source (Init) then
5628 -- We only give the warning for non-imported entities of a type for
5629 -- which a non-null base init proc is defined, or for objects of access
5630 -- types with implicit null initialization, or when Normalize_Scalars
5631 -- applies and the type is scalar or a string type (the latter being
5632 -- tested for because predefined String types are initialized by inline
5633 -- code rather than by an init_proc). Note that we do not give the
5634 -- warning for Initialize_Scalars, since we suppressed initialization
5638 and then not Is_Imported (Ent)
5639 and then (Has_Non_Null_Base_Init_Proc (Typ)
5640 or else Is_Access_Type (Typ)
5641 or else (Normalize_Scalars
5642 and then (Is_Scalar_Type (Typ)
5643 or else Is_String_Type (Typ))))
5645 if Nkind (Expr) = N_Attribute_Reference
5646 and then Is_Entity_Name (Prefix (Expr))
5648 Old := Entity (Prefix (Expr));
5650 elsif Is_Entity_Name (Expr)
5651 and then Ekind (Entity (Expr)) = E_Constant
5653 Decl := Declaration_Node (Entity (Expr));
5655 if Nkind (Decl) = N_Object_Declaration
5656 and then Present (Expression (Decl))
5657 and then Nkind (Expression (Decl)) = N_Attribute_Reference
5658 and then Is_Entity_Name (Prefix (Expression (Decl)))
5660 Old := Entity (Prefix (Expression (Decl)));
5662 elsif Nkind (Expr) = N_Function_Call then
5666 -- A function call (most likely to To_Address) is probably not an
5667 -- overlay, so skip warning. Ditto if the function call was inlined
5668 -- and transformed into an entity.
5670 elsif Nkind (Original_Node (Expr)) = N_Function_Call then
5674 Decl := Next (Parent (Expr));
5676 -- If a pragma Import follows, we assume that it is for the current
5677 -- target of the address clause, and skip the warning.
5680 and then Nkind (Decl) = N_Pragma
5681 and then Pragma_Name (Decl) = Name_Import
5686 if Present (Old) then
5687 Error_Msg_Node_2 := Old;
5689 ("default initialization of & may modify &?",
5693 ("default initialization of & may modify overlaid storage?",
5697 -- Add friendly warning if initialization comes from a packed array
5700 if Is_Record_Type (Typ) then
5705 Comp := First_Component (Typ);
5707 while Present (Comp) loop
5708 if Nkind (Parent (Comp)) = N_Component_Declaration
5709 and then Present (Expression (Parent (Comp)))
5712 elsif Is_Array_Type (Etype (Comp))
5713 and then Present (Packed_Array_Type (Etype (Comp)))
5716 ("\packed array component& " &
5717 "will be initialized to zero?",
5721 Next_Component (Comp);
5728 ("\use pragma Import for & to " &
5729 "suppress initialization (RM B.1(24))?",
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