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1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- F R E E Z E --
6 -- --
7 -- B o d y --
8 -- --
9 -- Copyright (C) 1992-2010, Free Software Foundation, Inc. --
10 -- --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 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. --
17 -- --
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/>. --
21 -- --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 -- --
25 ------------------------------------------------------------------------------
26
27 with Atree; use Atree;
28 with Debug; use Debug;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Errout; use Errout;
32 with Exp_Ch3; use Exp_Ch3;
33 with Exp_Ch7; use Exp_Ch7;
34 with Exp_Disp; use Exp_Disp;
35 with Exp_Pakd; use Exp_Pakd;
36 with Exp_Util; use Exp_Util;
37 with Exp_Tss; use Exp_Tss;
38 with Layout; use Layout;
39 with Lib; use Lib;
40 with Namet; use Namet;
41 with Nlists; use Nlists;
42 with Nmake; use Nmake;
43 with Opt; use Opt;
44 with Restrict; use Restrict;
45 with Rident; use Rident;
46 with Sem; use Sem;
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;
66
67 package body Freeze is
68
69 -----------------------
70 -- Local Subprograms --
71 -----------------------
72
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.
79
80 procedure Build_And_Analyze_Renamed_Body
81 (Decl : Node_Id;
82 New_S : Entity_Id;
83 After : in out Node_Id);
84 -- Build body for a renaming declaration, insert in tree and analyze
85
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.
89
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
93 -- Strict_Alignment.
94
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.
101
102 procedure Freeze_And_Append
103 (Ent : Entity_Id;
104 Loc : Source_Ptr;
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.
108
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.
115
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.
120
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).
129
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.
137
138 procedure Process_Default_Expressions
139 (E : Entity_Id;
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).
150
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.
155
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.
163
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.
168
169 procedure Warn_Overlay
170 (Expr : Node_Id;
171 Typ : Entity_Id;
172 Nam : Node_Id);
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.
178
179 -------------------------------
180 -- Adjust_Esize_For_Alignment --
181 -------------------------------
182
183 procedure Adjust_Esize_For_Alignment (Typ : Entity_Id) is
184 Align : Uint;
185
186 begin
187 if Known_Esize (Typ) and then Known_Alignment (Typ) then
188 Align := Alignment_In_Bits (Typ);
189
190 if Align > Esize (Typ)
191 and then Align <= Standard_Long_Long_Integer_Size
192 then
193 Set_Esize (Typ, Align);
194 end if;
195 end if;
196 end Adjust_Esize_For_Alignment;
197
198 ------------------------------------
199 -- Build_And_Analyze_Renamed_Body --
200 ------------------------------------
201
202 procedure Build_And_Analyze_Renamed_Body
203 (Decl : Node_Id;
204 New_S : Entity_Id;
205 After : in out Node_Id)
206 is
207 Body_Decl : constant Node_Id := Unit_Declaration_Node (New_S);
208 Ent : constant Entity_Id := Defining_Entity (Decl);
209 Body_Node : Node_Id;
210 Renamed_Subp : Entity_Id;
211
212 begin
213 -- If the renamed subprogram is intrinsic, there is no need for a
214 -- wrapper body: we set the alias that will be called and expanded which
215 -- completes the declaration. This transformation is only legal if the
216 -- renamed entity has already been elaborated.
217
218 -- Note that it is legal for a renaming_as_body to rename an intrinsic
219 -- subprogram, as long as the renaming occurs before the new entity
220 -- is frozen. See RM 8.5.4 (5).
221
222 if Nkind (Body_Decl) = N_Subprogram_Renaming_Declaration
223 and then Is_Entity_Name (Name (Body_Decl))
224 then
225 Renamed_Subp := Entity (Name (Body_Decl));
226 else
227 Renamed_Subp := Empty;
228 end if;
229
230 if Present (Renamed_Subp)
231 and then Is_Intrinsic_Subprogram (Renamed_Subp)
232 and then
233 (not In_Same_Source_Unit (Renamed_Subp, Ent)
234 or else Sloc (Renamed_Subp) < Sloc (Ent))
235
236 -- We can make the renaming entity intrisic if the renamed function
237 -- has an interface name, or if it is one of the shift/rotate
238 -- operations known to the compiler.
239
240 and then (Present (Interface_Name (Renamed_Subp))
241 or else Chars (Renamed_Subp) = Name_Rotate_Left
242 or else Chars (Renamed_Subp) = Name_Rotate_Right
243 or else Chars (Renamed_Subp) = Name_Shift_Left
244 or else Chars (Renamed_Subp) = Name_Shift_Right
245 or else Chars (Renamed_Subp) = Name_Shift_Right_Arithmetic)
246 then
247 Set_Interface_Name (Ent, Interface_Name (Renamed_Subp));
248
249 if Present (Alias (Renamed_Subp)) then
250 Set_Alias (Ent, Alias (Renamed_Subp));
251 else
252 Set_Alias (Ent, Renamed_Subp);
253 end if;
254
255 Set_Is_Intrinsic_Subprogram (Ent);
256 Set_Has_Completion (Ent);
257
258 else
259 Body_Node := Build_Renamed_Body (Decl, New_S);
260 Insert_After (After, Body_Node);
261 Mark_Rewrite_Insertion (Body_Node);
262 Analyze (Body_Node);
263 After := Body_Node;
264 end if;
265 end Build_And_Analyze_Renamed_Body;
266
267 ------------------------
268 -- Build_Renamed_Body --
269 ------------------------
270
271 function Build_Renamed_Body
272 (Decl : Node_Id;
273 New_S : Entity_Id) return Node_Id
274 is
275 Loc : constant Source_Ptr := Sloc (New_S);
276 -- We use for the source location of the renamed body, the location of
277 -- the spec entity. It might seem more natural to use the location of
278 -- the renaming declaration itself, but that would be wrong, since then
279 -- the body we create would look as though it was created far too late,
280 -- and this could cause problems with elaboration order analysis,
281 -- particularly in connection with instantiations.
282
283 N : constant Node_Id := Unit_Declaration_Node (New_S);
284 Nam : constant Node_Id := Name (N);
285 Old_S : Entity_Id;
286 Spec : constant Node_Id := New_Copy_Tree (Specification (Decl));
287 Actuals : List_Id := No_List;
288 Call_Node : Node_Id;
289 Call_Name : Node_Id;
290 Body_Node : Node_Id;
291 Formal : Entity_Id;
292 O_Formal : Entity_Id;
293 Param_Spec : Node_Id;
294
295 Pref : Node_Id := Empty;
296 -- If the renamed entity is a primitive operation given in prefix form,
297 -- the prefix is the target object and it has to be added as the first
298 -- actual in the generated call.
299
300 begin
301 -- Determine the entity being renamed, which is the target of the call
302 -- statement. If the name is an explicit dereference, this is a renaming
303 -- of a subprogram type rather than a subprogram. The name itself is
304 -- fully analyzed.
305
306 if Nkind (Nam) = N_Selected_Component then
307 Old_S := Entity (Selector_Name (Nam));
308
309 elsif Nkind (Nam) = N_Explicit_Dereference then
310 Old_S := Etype (Nam);
311
312 elsif Nkind (Nam) = N_Indexed_Component then
313 if Is_Entity_Name (Prefix (Nam)) then
314 Old_S := Entity (Prefix (Nam));
315 else
316 Old_S := Entity (Selector_Name (Prefix (Nam)));
317 end if;
318
319 elsif Nkind (Nam) = N_Character_Literal then
320 Old_S := Etype (New_S);
321
322 else
323 Old_S := Entity (Nam);
324 end if;
325
326 if Is_Entity_Name (Nam) then
327
328 -- If the renamed entity is a predefined operator, retain full name
329 -- to ensure its visibility.
330
331 if Ekind (Old_S) = E_Operator
332 and then Nkind (Nam) = N_Expanded_Name
333 then
334 Call_Name := New_Copy (Name (N));
335 else
336 Call_Name := New_Reference_To (Old_S, Loc);
337 end if;
338
339 else
340 if Nkind (Nam) = N_Selected_Component
341 and then Present (First_Formal (Old_S))
342 and then
343 (Is_Controlling_Formal (First_Formal (Old_S))
344 or else Is_Class_Wide_Type (Etype (First_Formal (Old_S))))
345 then
346
347 -- Retrieve the target object, to be added as a first actual
348 -- in the call.
349
350 Call_Name := New_Occurrence_Of (Old_S, Loc);
351 Pref := Prefix (Nam);
352
353 else
354 Call_Name := New_Copy (Name (N));
355 end if;
356
357 -- Original name may have been overloaded, but is fully resolved now
358
359 Set_Is_Overloaded (Call_Name, False);
360 end if;
361
362 -- For simple renamings, subsequent calls can be expanded directly as
363 -- calls to the renamed entity. The body must be generated in any case
364 -- for calls that may appear elsewhere.
365
366 if Ekind_In (Old_S, E_Function, E_Procedure)
367 and then Nkind (Decl) = N_Subprogram_Declaration
368 then
369 Set_Body_To_Inline (Decl, Old_S);
370 end if;
371
372 -- The body generated for this renaming is an internal artifact, and
373 -- does not constitute a freeze point for the called entity.
374
375 Set_Must_Not_Freeze (Call_Name);
376
377 Formal := First_Formal (Defining_Entity (Decl));
378
379 if Present (Pref) then
380 declare
381 Pref_Type : constant Entity_Id := Etype (Pref);
382 Form_Type : constant Entity_Id := Etype (First_Formal (Old_S));
383
384 begin
385 -- The controlling formal may be an access parameter, or the
386 -- actual may be an access value, so adjust accordingly.
387
388 if Is_Access_Type (Pref_Type)
389 and then not Is_Access_Type (Form_Type)
390 then
391 Actuals := New_List
392 (Make_Explicit_Dereference (Loc, Relocate_Node (Pref)));
393
394 elsif Is_Access_Type (Form_Type)
395 and then not Is_Access_Type (Pref)
396 then
397 Actuals := New_List
398 (Make_Attribute_Reference (Loc,
399 Attribute_Name => Name_Access,
400 Prefix => Relocate_Node (Pref)));
401 else
402 Actuals := New_List (Pref);
403 end if;
404 end;
405
406 elsif Present (Formal) then
407 Actuals := New_List;
408
409 else
410 Actuals := No_List;
411 end if;
412
413 if Present (Formal) then
414 while Present (Formal) loop
415 Append (New_Reference_To (Formal, Loc), Actuals);
416 Next_Formal (Formal);
417 end loop;
418 end if;
419
420 -- If the renamed entity is an entry, inherit its profile. For other
421 -- renamings as bodies, both profiles must be subtype conformant, so it
422 -- is not necessary to replace the profile given in the declaration.
423 -- However, default values that are aggregates are rewritten when
424 -- partially analyzed, so we recover the original aggregate to insure
425 -- that subsequent conformity checking works. Similarly, if the default
426 -- expression was constant-folded, recover the original expression.
427
428 Formal := First_Formal (Defining_Entity (Decl));
429
430 if Present (Formal) then
431 O_Formal := First_Formal (Old_S);
432 Param_Spec := First (Parameter_Specifications (Spec));
433 while Present (Formal) loop
434 if Is_Entry (Old_S) then
435 if Nkind (Parameter_Type (Param_Spec)) /=
436 N_Access_Definition
437 then
438 Set_Etype (Formal, Etype (O_Formal));
439 Set_Entity (Parameter_Type (Param_Spec), Etype (O_Formal));
440 end if;
441
442 elsif Nkind (Default_Value (O_Formal)) = N_Aggregate
443 or else Nkind (Original_Node (Default_Value (O_Formal))) /=
444 Nkind (Default_Value (O_Formal))
445 then
446 Set_Expression (Param_Spec,
447 New_Copy_Tree (Original_Node (Default_Value (O_Formal))));
448 end if;
449
450 Next_Formal (Formal);
451 Next_Formal (O_Formal);
452 Next (Param_Spec);
453 end loop;
454 end if;
455
456 -- If the renamed entity is a function, the generated body contains a
457 -- return statement. Otherwise, build a procedure call. If the entity is
458 -- an entry, subsequent analysis of the call will transform it into the
459 -- proper entry or protected operation call. If the renamed entity is
460 -- a character literal, return it directly.
461
462 if Ekind (Old_S) = E_Function
463 or else Ekind (Old_S) = E_Operator
464 or else (Ekind (Old_S) = E_Subprogram_Type
465 and then Etype (Old_S) /= Standard_Void_Type)
466 then
467 Call_Node :=
468 Make_Simple_Return_Statement (Loc,
469 Expression =>
470 Make_Function_Call (Loc,
471 Name => Call_Name,
472 Parameter_Associations => Actuals));
473
474 elsif Ekind (Old_S) = E_Enumeration_Literal then
475 Call_Node :=
476 Make_Simple_Return_Statement (Loc,
477 Expression => New_Occurrence_Of (Old_S, Loc));
478
479 elsif Nkind (Nam) = N_Character_Literal then
480 Call_Node :=
481 Make_Simple_Return_Statement (Loc,
482 Expression => Call_Name);
483
484 else
485 Call_Node :=
486 Make_Procedure_Call_Statement (Loc,
487 Name => Call_Name,
488 Parameter_Associations => Actuals);
489 end if;
490
491 -- Create entities for subprogram body and formals
492
493 Set_Defining_Unit_Name (Spec,
494 Make_Defining_Identifier (Loc, Chars => Chars (New_S)));
495
496 Param_Spec := First (Parameter_Specifications (Spec));
497 while Present (Param_Spec) loop
498 Set_Defining_Identifier (Param_Spec,
499 Make_Defining_Identifier (Loc,
500 Chars => Chars (Defining_Identifier (Param_Spec))));
501 Next (Param_Spec);
502 end loop;
503
504 Body_Node :=
505 Make_Subprogram_Body (Loc,
506 Specification => Spec,
507 Declarations => New_List,
508 Handled_Statement_Sequence =>
509 Make_Handled_Sequence_Of_Statements (Loc,
510 Statements => New_List (Call_Node)));
511
512 if Nkind (Decl) /= N_Subprogram_Declaration then
513 Rewrite (N,
514 Make_Subprogram_Declaration (Loc,
515 Specification => Specification (N)));
516 end if;
517
518 -- Link the body to the entity whose declaration it completes. If
519 -- the body is analyzed when the renamed entity is frozen, it may
520 -- be necessary to restore the proper scope (see package Exp_Ch13).
521
522 if Nkind (N) = N_Subprogram_Renaming_Declaration
523 and then Present (Corresponding_Spec (N))
524 then
525 Set_Corresponding_Spec (Body_Node, Corresponding_Spec (N));
526 else
527 Set_Corresponding_Spec (Body_Node, New_S);
528 end if;
529
530 return Body_Node;
531 end Build_Renamed_Body;
532
533 --------------------------
534 -- Check_Address_Clause --
535 --------------------------
536
537 procedure Check_Address_Clause (E : Entity_Id) is
538 Addr : constant Node_Id := Address_Clause (E);
539 Expr : Node_Id;
540 Decl : constant Node_Id := Declaration_Node (E);
541 Typ : constant Entity_Id := Etype (E);
542
543 begin
544 if Present (Addr) then
545 Expr := Expression (Addr);
546
547 if Needs_Constant_Address (Decl, Typ) then
548 Check_Constant_Address_Clause (Expr, E);
549
550 -- Has_Delayed_Freeze was set on E when the address clause was
551 -- analyzed. Reset the flag now unless freeze actions were
552 -- attached to it in the mean time.
553
554 if No (Freeze_Node (E)) then
555 Set_Has_Delayed_Freeze (E, False);
556 end if;
557 end if;
558
559 -- If Rep_Clauses are to be ignored, remove address clause from
560 -- list attached to entity, because it may be illegal for gigi,
561 -- for example by breaking order of elaboration..
562
563 if Ignore_Rep_Clauses then
564 declare
565 Rep : Node_Id;
566
567 begin
568 Rep := First_Rep_Item (E);
569
570 if Rep = Addr then
571 Set_First_Rep_Item (E, Next_Rep_Item (Addr));
572
573 else
574 while Present (Rep)
575 and then Next_Rep_Item (Rep) /= Addr
576 loop
577 Rep := Next_Rep_Item (Rep);
578 end loop;
579 end if;
580
581 if Present (Rep) then
582 Set_Next_Rep_Item (Rep, Next_Rep_Item (Addr));
583 end if;
584 end;
585
586 Rewrite (Addr, Make_Null_Statement (Sloc (E)));
587
588 elsif not Error_Posted (Expr)
589 and then not Needs_Finalization (Typ)
590 then
591 Warn_Overlay (Expr, Typ, Name (Addr));
592 end if;
593 end if;
594 end Check_Address_Clause;
595
596 -----------------------------
597 -- Check_Compile_Time_Size --
598 -----------------------------
599
600 procedure Check_Compile_Time_Size (T : Entity_Id) is
601
602 procedure Set_Small_Size (T : Entity_Id; S : Uint);
603 -- Sets the compile time known size (32 bits or less) in the Esize
604 -- field, of T checking for a size clause that was given which attempts
605 -- to give a smaller size, and also checking for an alignment clause.
606
607 function Size_Known (T : Entity_Id) return Boolean;
608 -- Recursive function that does all the work
609
610 function Static_Discriminated_Components (T : Entity_Id) return Boolean;
611 -- If T is a constrained subtype, its size is not known if any of its
612 -- discriminant constraints is not static and it is not a null record.
613 -- The test is conservative and doesn't check that the components are
614 -- in fact constrained by non-static discriminant values. Could be made
615 -- more precise ???
616
617 --------------------
618 -- Set_Small_Size --
619 --------------------
620
621 procedure Set_Small_Size (T : Entity_Id; S : Uint) is
622 begin
623 if S > 32 then
624 return;
625
626 -- Don't bother if alignment clause with a value other than 1 is
627 -- present, because size may be padded up to meet back end alignment
628 -- requirements, and only the back end knows the rules!
629
630 elsif Known_Alignment (T) and then Alignment (T) /= 1 then
631 return;
632
633 -- Check for bad size clause given
634
635 elsif Has_Size_Clause (T) then
636 if RM_Size (T) < S then
637 Error_Msg_Uint_1 := S;
638 Error_Msg_NE
639 ("size for& too small, minimum allowed is ^",
640 Size_Clause (T), T);
641
642 elsif Unknown_Esize (T) then
643 Set_Esize (T, S);
644 end if;
645
646 -- Set sizes if not set already
647
648 else
649 if Unknown_Esize (T) then
650 Set_Esize (T, S);
651 end if;
652
653 if Unknown_RM_Size (T) then
654 Set_RM_Size (T, S);
655 end if;
656 end if;
657 end Set_Small_Size;
658
659 ----------------
660 -- Size_Known --
661 ----------------
662
663 function Size_Known (T : Entity_Id) return Boolean is
664 Index : Entity_Id;
665 Comp : Entity_Id;
666 Ctyp : Entity_Id;
667 Low : Node_Id;
668 High : Node_Id;
669
670 begin
671 if Size_Known_At_Compile_Time (T) then
672 return True;
673
674 -- Always True for scalar types. This is true even for generic formal
675 -- scalar types. We used to return False in the latter case, but the
676 -- size is known at compile time, even in the template, we just do
677 -- not know the exact size but that's not the point of this routine.
678
679 elsif Is_Scalar_Type (T)
680 or else Is_Task_Type (T)
681 then
682 return True;
683
684 -- Array types
685
686 elsif Is_Array_Type (T) then
687
688 -- String literals always have known size, and we can set it
689
690 if Ekind (T) = E_String_Literal_Subtype then
691 Set_Small_Size (T, Component_Size (T)
692 * String_Literal_Length (T));
693 return True;
694
695 -- Unconstrained types never have known at compile time size
696
697 elsif not Is_Constrained (T) then
698 return False;
699
700 -- Don't do any recursion on type with error posted, since we may
701 -- have a malformed type that leads us into a loop.
702
703 elsif Error_Posted (T) then
704 return False;
705
706 -- Otherwise if component size unknown, then array size unknown
707
708 elsif not Size_Known (Component_Type (T)) then
709 return False;
710 end if;
711
712 -- Check for all indexes static, and also compute possible size
713 -- (in case it is less than 32 and may be packable).
714
715 declare
716 Esiz : Uint := Component_Size (T);
717 Dim : Uint;
718
719 begin
720 Index := First_Index (T);
721 while Present (Index) loop
722 if Nkind (Index) = N_Range then
723 Get_Index_Bounds (Index, Low, High);
724
725 elsif Error_Posted (Scalar_Range (Etype (Index))) then
726 return False;
727
728 else
729 Low := Type_Low_Bound (Etype (Index));
730 High := Type_High_Bound (Etype (Index));
731 end if;
732
733 if not Compile_Time_Known_Value (Low)
734 or else not Compile_Time_Known_Value (High)
735 or else Etype (Index) = Any_Type
736 then
737 return False;
738
739 else
740 Dim := Expr_Value (High) - Expr_Value (Low) + 1;
741
742 if Dim >= 0 then
743 Esiz := Esiz * Dim;
744 else
745 Esiz := Uint_0;
746 end if;
747 end if;
748
749 Next_Index (Index);
750 end loop;
751
752 Set_Small_Size (T, Esiz);
753 return True;
754 end;
755
756 -- Access types always have known at compile time sizes
757
758 elsif Is_Access_Type (T) then
759 return True;
760
761 -- For non-generic private types, go to underlying type if present
762
763 elsif Is_Private_Type (T)
764 and then not Is_Generic_Type (T)
765 and then Present (Underlying_Type (T))
766 then
767 -- Don't do any recursion on type with error posted, since we may
768 -- have a malformed type that leads us into a loop.
769
770 if Error_Posted (T) then
771 return False;
772 else
773 return Size_Known (Underlying_Type (T));
774 end if;
775
776 -- Record types
777
778 elsif Is_Record_Type (T) then
779
780 -- A class-wide type is never considered to have a known size
781
782 if Is_Class_Wide_Type (T) then
783 return False;
784
785 -- A subtype of a variant record must not have non-static
786 -- discriminanted components.
787
788 elsif T /= Base_Type (T)
789 and then not Static_Discriminated_Components (T)
790 then
791 return False;
792
793 -- Don't do any recursion on type with error posted, since we may
794 -- have a malformed type that leads us into a loop.
795
796 elsif Error_Posted (T) then
797 return False;
798 end if;
799
800 -- Now look at the components of the record
801
802 declare
803 -- The following two variables are used to keep track of the
804 -- size of packed records if we can tell the size of the packed
805 -- record in the front end. Packed_Size_Known is True if so far
806 -- we can figure out the size. It is initialized to True for a
807 -- packed record, unless the record has discriminants. The
808 -- reason we eliminate the discriminated case is that we don't
809 -- know the way the back end lays out discriminated packed
810 -- records. If Packed_Size_Known is True, then Packed_Size is
811 -- the size in bits so far.
812
813 Packed_Size_Known : Boolean :=
814 Is_Packed (T)
815 and then not Has_Discriminants (T);
816
817 Packed_Size : Uint := Uint_0;
818
819 begin
820 -- Test for variant part present
821
822 if Has_Discriminants (T)
823 and then Present (Parent (T))
824 and then Nkind (Parent (T)) = N_Full_Type_Declaration
825 and then Nkind (Type_Definition (Parent (T))) =
826 N_Record_Definition
827 and then not Null_Present (Type_Definition (Parent (T)))
828 and then Present (Variant_Part
829 (Component_List (Type_Definition (Parent (T)))))
830 then
831 -- If variant part is present, and type is unconstrained,
832 -- then we must have defaulted discriminants, or a size
833 -- clause must be present for the type, or else the size
834 -- is definitely not known at compile time.
835
836 if not Is_Constrained (T)
837 and then
838 No (Discriminant_Default_Value (First_Discriminant (T)))
839 and then Unknown_Esize (T)
840 then
841 return False;
842 end if;
843 end if;
844
845 -- Loop through components
846
847 Comp := First_Component_Or_Discriminant (T);
848 while Present (Comp) loop
849 Ctyp := Etype (Comp);
850
851 -- We do not know the packed size if there is a component
852 -- clause present (we possibly could, but this would only
853 -- help in the case of a record with partial rep clauses.
854 -- That's because in the case of full rep clauses, the
855 -- size gets figured out anyway by a different circuit).
856
857 if Present (Component_Clause (Comp)) then
858 Packed_Size_Known := False;
859 end if;
860
861 -- We need to identify a component that is an array where
862 -- the index type is an enumeration type with non-standard
863 -- representation, and some bound of the type depends on a
864 -- discriminant.
865
866 -- This is because gigi computes the size by doing a
867 -- substitution of the appropriate discriminant value in
868 -- the size expression for the base type, and gigi is not
869 -- clever enough to evaluate the resulting expression (which
870 -- involves a call to rep_to_pos) at compile time.
871
872 -- It would be nice if gigi would either recognize that
873 -- this expression can be computed at compile time, or
874 -- alternatively figured out the size from the subtype
875 -- directly, where all the information is at hand ???
876
877 if Is_Array_Type (Etype (Comp))
878 and then Present (Packed_Array_Type (Etype (Comp)))
879 then
880 declare
881 Ocomp : constant Entity_Id :=
882 Original_Record_Component (Comp);
883 OCtyp : constant Entity_Id := Etype (Ocomp);
884 Ind : Node_Id;
885 Indtyp : Entity_Id;
886 Lo, Hi : Node_Id;
887
888 begin
889 Ind := First_Index (OCtyp);
890 while Present (Ind) loop
891 Indtyp := Etype (Ind);
892
893 if Is_Enumeration_Type (Indtyp)
894 and then Has_Non_Standard_Rep (Indtyp)
895 then
896 Lo := Type_Low_Bound (Indtyp);
897 Hi := Type_High_Bound (Indtyp);
898
899 if Is_Entity_Name (Lo)
900 and then Ekind (Entity (Lo)) = E_Discriminant
901 then
902 return False;
903
904 elsif Is_Entity_Name (Hi)
905 and then Ekind (Entity (Hi)) = E_Discriminant
906 then
907 return False;
908 end if;
909 end if;
910
911 Next_Index (Ind);
912 end loop;
913 end;
914 end if;
915
916 -- Clearly size of record is not known if the size of one of
917 -- the components is not known.
918
919 if not Size_Known (Ctyp) then
920 return False;
921 end if;
922
923 -- Accumulate packed size if possible
924
925 if Packed_Size_Known then
926
927 -- We can only deal with elementary types, since for
928 -- non-elementary components, alignment enters into the
929 -- picture, and we don't know enough to handle proper
930 -- alignment in this context. Packed arrays count as
931 -- elementary if the representation is a modular type.
932
933 if Is_Elementary_Type (Ctyp)
934 or else (Is_Array_Type (Ctyp)
935 and then Present (Packed_Array_Type (Ctyp))
936 and then Is_Modular_Integer_Type
937 (Packed_Array_Type (Ctyp)))
938 then
939 -- If RM_Size is known and static, then we can keep
940 -- accumulating the packed size.
941
942 if Known_Static_RM_Size (Ctyp) then
943
944 -- A little glitch, to be removed sometime ???
945 -- gigi does not understand zero sizes yet.
946
947 if RM_Size (Ctyp) = Uint_0 then
948 Packed_Size_Known := False;
949
950 -- Normal case where we can keep accumulating the
951 -- packed array size.
952
953 else
954 Packed_Size := Packed_Size + RM_Size (Ctyp);
955 end if;
956
957 -- If we have a field whose RM_Size is not known then
958 -- we can't figure out the packed size here.
959
960 else
961 Packed_Size_Known := False;
962 end if;
963
964 -- If we have a non-elementary type we can't figure out
965 -- the packed array size (alignment issues).
966
967 else
968 Packed_Size_Known := False;
969 end if;
970 end if;
971
972 Next_Component_Or_Discriminant (Comp);
973 end loop;
974
975 if Packed_Size_Known then
976 Set_Small_Size (T, Packed_Size);
977 end if;
978
979 return True;
980 end;
981
982 -- All other cases, size not known at compile time
983
984 else
985 return False;
986 end if;
987 end Size_Known;
988
989 -------------------------------------
990 -- Static_Discriminated_Components --
991 -------------------------------------
992
993 function Static_Discriminated_Components
994 (T : Entity_Id) return Boolean
995 is
996 Constraint : Elmt_Id;
997
998 begin
999 if Has_Discriminants (T)
1000 and then Present (Discriminant_Constraint (T))
1001 and then Present (First_Component (T))
1002 then
1003 Constraint := First_Elmt (Discriminant_Constraint (T));
1004 while Present (Constraint) loop
1005 if not Compile_Time_Known_Value (Node (Constraint)) then
1006 return False;
1007 end if;
1008
1009 Next_Elmt (Constraint);
1010 end loop;
1011 end if;
1012
1013 return True;
1014 end Static_Discriminated_Components;
1015
1016 -- Start of processing for Check_Compile_Time_Size
1017
1018 begin
1019 Set_Size_Known_At_Compile_Time (T, Size_Known (T));
1020 end Check_Compile_Time_Size;
1021
1022 -----------------------------
1023 -- Check_Debug_Info_Needed --
1024 -----------------------------
1025
1026 procedure Check_Debug_Info_Needed (T : Entity_Id) is
1027 begin
1028 if Debug_Info_Off (T) then
1029 return;
1030
1031 elsif Comes_From_Source (T)
1032 or else Debug_Generated_Code
1033 or else Debug_Flag_VV
1034 or else Needs_Debug_Info (T)
1035 then
1036 Set_Debug_Info_Needed (T);
1037 end if;
1038 end Check_Debug_Info_Needed;
1039
1040 ----------------------------
1041 -- Check_Strict_Alignment --
1042 ----------------------------
1043
1044 procedure Check_Strict_Alignment (E : Entity_Id) is
1045 Comp : Entity_Id;
1046
1047 begin
1048 if Is_Tagged_Type (E) or else Is_Concurrent_Type (E) then
1049 Set_Strict_Alignment (E);
1050
1051 elsif Is_Array_Type (E) then
1052 Set_Strict_Alignment (E, Strict_Alignment (Component_Type (E)));
1053
1054 elsif Is_Record_Type (E) then
1055 if Is_Limited_Record (E) then
1056 Set_Strict_Alignment (E);
1057 return;
1058 end if;
1059
1060 Comp := First_Component (E);
1061 while Present (Comp) loop
1062 if not Is_Type (Comp)
1063 and then (Strict_Alignment (Etype (Comp))
1064 or else Is_Aliased (Comp))
1065 then
1066 Set_Strict_Alignment (E);
1067 return;
1068 end if;
1069
1070 Next_Component (Comp);
1071 end loop;
1072 end if;
1073 end Check_Strict_Alignment;
1074
1075 -------------------------
1076 -- Check_Unsigned_Type --
1077 -------------------------
1078
1079 procedure Check_Unsigned_Type (E : Entity_Id) is
1080 Ancestor : Entity_Id;
1081 Lo_Bound : Node_Id;
1082 Btyp : Entity_Id;
1083
1084 begin
1085 if not Is_Discrete_Or_Fixed_Point_Type (E) then
1086 return;
1087 end if;
1088
1089 -- Do not attempt to analyze case where range was in error
1090
1091 if No (Scalar_Range (E))
1092 or else Error_Posted (Scalar_Range (E))
1093 then
1094 return;
1095 end if;
1096
1097 -- The situation that is non trivial is something like
1098
1099 -- subtype x1 is integer range -10 .. +10;
1100 -- subtype x2 is x1 range 0 .. V1;
1101 -- subtype x3 is x2 range V2 .. V3;
1102 -- subtype x4 is x3 range V4 .. V5;
1103
1104 -- where Vn are variables. Here the base type is signed, but we still
1105 -- know that x4 is unsigned because of the lower bound of x2.
1106
1107 -- The only way to deal with this is to look up the ancestor chain
1108
1109 Ancestor := E;
1110 loop
1111 if Ancestor = Any_Type or else Etype (Ancestor) = Any_Type then
1112 return;
1113 end if;
1114
1115 Lo_Bound := Type_Low_Bound (Ancestor);
1116
1117 if Compile_Time_Known_Value (Lo_Bound) then
1118
1119 if Expr_Rep_Value (Lo_Bound) >= 0 then
1120 Set_Is_Unsigned_Type (E, True);
1121 end if;
1122
1123 return;
1124
1125 else
1126 Ancestor := Ancestor_Subtype (Ancestor);
1127
1128 -- If no ancestor had a static lower bound, go to base type
1129
1130 if No (Ancestor) then
1131
1132 -- Note: the reason we still check for a compile time known
1133 -- value for the base type is that at least in the case of
1134 -- generic formals, we can have bounds that fail this test,
1135 -- and there may be other cases in error situations.
1136
1137 Btyp := Base_Type (E);
1138
1139 if Btyp = Any_Type or else Etype (Btyp) = Any_Type then
1140 return;
1141 end if;
1142
1143 Lo_Bound := Type_Low_Bound (Base_Type (E));
1144
1145 if Compile_Time_Known_Value (Lo_Bound)
1146 and then Expr_Rep_Value (Lo_Bound) >= 0
1147 then
1148 Set_Is_Unsigned_Type (E, True);
1149 end if;
1150
1151 return;
1152 end if;
1153 end if;
1154 end loop;
1155 end Check_Unsigned_Type;
1156
1157 -------------------------
1158 -- Is_Atomic_Aggregate --
1159 -------------------------
1160
1161 function Is_Atomic_Aggregate
1162 (E : Entity_Id;
1163 Typ : Entity_Id) return Boolean
1164 is
1165 Loc : constant Source_Ptr := Sloc (E);
1166 New_N : Node_Id;
1167 Par : Node_Id;
1168 Temp : Entity_Id;
1169
1170 begin
1171 Par := Parent (E);
1172
1173 -- Array may be qualified, so find outer context
1174
1175 if Nkind (Par) = N_Qualified_Expression then
1176 Par := Parent (Par);
1177 end if;
1178
1179 if Nkind_In (Par, N_Object_Declaration, N_Assignment_Statement)
1180 and then Comes_From_Source (Par)
1181 then
1182 Temp := Make_Temporary (Loc, 'T', E);
1183 New_N :=
1184 Make_Object_Declaration (Loc,
1185 Defining_Identifier => Temp,
1186 Object_Definition => New_Occurrence_Of (Typ, Loc),
1187 Expression => Relocate_Node (E));
1188 Insert_Before (Par, New_N);
1189 Analyze (New_N);
1190
1191 Set_Expression (Par, New_Occurrence_Of (Temp, Loc));
1192 return True;
1193
1194 else
1195 return False;
1196 end if;
1197 end Is_Atomic_Aggregate;
1198
1199 ----------------
1200 -- Freeze_All --
1201 ----------------
1202
1203 -- Note: the easy coding for this procedure would be to just build a
1204 -- single list of freeze nodes and then insert them and analyze them
1205 -- all at once. This won't work, because the analysis of earlier freeze
1206 -- nodes may recursively freeze types which would otherwise appear later
1207 -- on in the freeze list. So we must analyze and expand the freeze nodes
1208 -- as they are generated.
1209
1210 procedure Freeze_All (From : Entity_Id; After : in out Node_Id) is
1211 Loc : constant Source_Ptr := Sloc (After);
1212 E : Entity_Id;
1213 Decl : Node_Id;
1214
1215 procedure Freeze_All_Ent (From : Entity_Id; After : in out Node_Id);
1216 -- This is the internal recursive routine that does freezing of entities
1217 -- (but NOT the analysis of default expressions, which should not be
1218 -- recursive, we don't want to analyze those till we are sure that ALL
1219 -- the types are frozen).
1220
1221 --------------------
1222 -- Freeze_All_Ent --
1223 --------------------
1224
1225 procedure Freeze_All_Ent (From : Entity_Id; After : in out Node_Id) is
1226 E : Entity_Id;
1227 Flist : List_Id;
1228 Lastn : Node_Id;
1229
1230 procedure Process_Flist;
1231 -- If freeze nodes are present, insert and analyze, and reset cursor
1232 -- for next insertion.
1233
1234 -------------------
1235 -- Process_Flist --
1236 -------------------
1237
1238 procedure Process_Flist is
1239 begin
1240 if Is_Non_Empty_List (Flist) then
1241 Lastn := Next (After);
1242 Insert_List_After_And_Analyze (After, Flist);
1243
1244 if Present (Lastn) then
1245 After := Prev (Lastn);
1246 else
1247 After := Last (List_Containing (After));
1248 end if;
1249 end if;
1250 end Process_Flist;
1251
1252 -- Start or processing for Freeze_All_Ent
1253
1254 begin
1255 E := From;
1256 while Present (E) loop
1257
1258 -- If the entity is an inner package which is not a package
1259 -- renaming, then its entities must be frozen at this point. Note
1260 -- that such entities do NOT get frozen at the end of the nested
1261 -- package itself (only library packages freeze).
1262
1263 -- Same is true for task declarations, where anonymous records
1264 -- created for entry parameters must be frozen.
1265
1266 if Ekind (E) = E_Package
1267 and then No (Renamed_Object (E))
1268 and then not Is_Child_Unit (E)
1269 and then not Is_Frozen (E)
1270 then
1271 Push_Scope (E);
1272 Install_Visible_Declarations (E);
1273 Install_Private_Declarations (E);
1274
1275 Freeze_All (First_Entity (E), After);
1276
1277 End_Package_Scope (E);
1278
1279 elsif Ekind (E) in Task_Kind
1280 and then
1281 (Nkind (Parent (E)) = N_Task_Type_Declaration
1282 or else
1283 Nkind (Parent (E)) = N_Single_Task_Declaration)
1284 then
1285 Push_Scope (E);
1286 Freeze_All (First_Entity (E), After);
1287 End_Scope;
1288
1289 -- For a derived tagged type, we must ensure that all the
1290 -- primitive operations of the parent have been frozen, so that
1291 -- their addresses will be in the parent's dispatch table at the
1292 -- point it is inherited.
1293
1294 elsif Ekind (E) = E_Record_Type
1295 and then Is_Tagged_Type (E)
1296 and then Is_Tagged_Type (Etype (E))
1297 and then Is_Derived_Type (E)
1298 then
1299 declare
1300 Prim_List : constant Elist_Id :=
1301 Primitive_Operations (Etype (E));
1302
1303 Prim : Elmt_Id;
1304 Subp : Entity_Id;
1305
1306 begin
1307 Prim := First_Elmt (Prim_List);
1308 while Present (Prim) loop
1309 Subp := Node (Prim);
1310
1311 if Comes_From_Source (Subp)
1312 and then not Is_Frozen (Subp)
1313 then
1314 Flist := Freeze_Entity (Subp, Loc);
1315 Process_Flist;
1316 end if;
1317
1318 Next_Elmt (Prim);
1319 end loop;
1320 end;
1321 end if;
1322
1323 if not Is_Frozen (E) then
1324 Flist := Freeze_Entity (E, Loc);
1325 Process_Flist;
1326 end if;
1327
1328 -- If an incomplete type is still not frozen, this may be a
1329 -- premature freezing because of a body declaration that follows.
1330 -- Indicate where the freezing took place.
1331
1332 -- If the freezing is caused by the end of the current declarative
1333 -- part, it is a Taft Amendment type, and there is no error.
1334
1335 if not Is_Frozen (E)
1336 and then Ekind (E) = E_Incomplete_Type
1337 then
1338 declare
1339 Bod : constant Node_Id := Next (After);
1340
1341 begin
1342 if (Nkind_In (Bod, N_Subprogram_Body,
1343 N_Entry_Body,
1344 N_Package_Body,
1345 N_Protected_Body,
1346 N_Task_Body)
1347 or else Nkind (Bod) in N_Body_Stub)
1348 and then
1349 List_Containing (After) = List_Containing (Parent (E))
1350 then
1351 Error_Msg_Sloc := Sloc (Next (After));
1352 Error_Msg_NE
1353 ("type& is frozen# before its full declaration",
1354 Parent (E), E);
1355 end if;
1356 end;
1357 end if;
1358
1359 Next_Entity (E);
1360 end loop;
1361 end Freeze_All_Ent;
1362
1363 -- Start of processing for Freeze_All
1364
1365 begin
1366 Freeze_All_Ent (From, After);
1367
1368 -- Now that all types are frozen, we can deal with default expressions
1369 -- that require us to build a default expression functions. This is the
1370 -- point at which such functions are constructed (after all types that
1371 -- might be used in such expressions have been frozen).
1372
1373 -- For subprograms that are renaming_as_body, we create the wrapper
1374 -- bodies as needed.
1375
1376 -- We also add finalization chains to access types whose designated
1377 -- types are controlled. This is normally done when freezing the type,
1378 -- but this misses recursive type definitions where the later members
1379 -- of the recursion introduce controlled components.
1380
1381 -- Loop through entities
1382
1383 E := From;
1384 while Present (E) loop
1385 if Is_Subprogram (E) then
1386
1387 if not Default_Expressions_Processed (E) then
1388 Process_Default_Expressions (E, After);
1389 end if;
1390
1391 if not Has_Completion (E) then
1392 Decl := Unit_Declaration_Node (E);
1393
1394 if Nkind (Decl) = N_Subprogram_Renaming_Declaration then
1395 Build_And_Analyze_Renamed_Body (Decl, E, After);
1396
1397 elsif Nkind (Decl) = N_Subprogram_Declaration
1398 and then Present (Corresponding_Body (Decl))
1399 and then
1400 Nkind (Unit_Declaration_Node (Corresponding_Body (Decl)))
1401 = N_Subprogram_Renaming_Declaration
1402 then
1403 Build_And_Analyze_Renamed_Body
1404 (Decl, Corresponding_Body (Decl), After);
1405 end if;
1406 end if;
1407
1408 elsif Ekind (E) in Task_Kind
1409 and then
1410 (Nkind (Parent (E)) = N_Task_Type_Declaration
1411 or else
1412 Nkind (Parent (E)) = N_Single_Task_Declaration)
1413 then
1414 declare
1415 Ent : Entity_Id;
1416
1417 begin
1418 Ent := First_Entity (E);
1419 while Present (Ent) loop
1420 if Is_Entry (Ent)
1421 and then not Default_Expressions_Processed (Ent)
1422 then
1423 Process_Default_Expressions (Ent, After);
1424 end if;
1425
1426 Next_Entity (Ent);
1427 end loop;
1428 end;
1429
1430 elsif Is_Access_Type (E)
1431 and then Comes_From_Source (E)
1432 and then Ekind (Directly_Designated_Type (E)) = E_Incomplete_Type
1433 and then Needs_Finalization (Designated_Type (E))
1434 and then No (Associated_Final_Chain (E))
1435 then
1436 Build_Final_List (Parent (E), E);
1437 end if;
1438
1439 Next_Entity (E);
1440 end loop;
1441 end Freeze_All;
1442
1443 -----------------------
1444 -- Freeze_And_Append --
1445 -----------------------
1446
1447 procedure Freeze_And_Append
1448 (Ent : Entity_Id;
1449 Loc : Source_Ptr;
1450 Result : in out List_Id)
1451 is
1452 L : constant List_Id := Freeze_Entity (Ent, Loc);
1453 begin
1454 if Is_Non_Empty_List (L) then
1455 if Result = No_List then
1456 Result := L;
1457 else
1458 Append_List (L, Result);
1459 end if;
1460 end if;
1461 end Freeze_And_Append;
1462
1463 -------------------
1464 -- Freeze_Before --
1465 -------------------
1466
1467 procedure Freeze_Before (N : Node_Id; T : Entity_Id) is
1468 Freeze_Nodes : constant List_Id := Freeze_Entity (T, Sloc (N));
1469 begin
1470 if Is_Non_Empty_List (Freeze_Nodes) then
1471 Insert_Actions (N, Freeze_Nodes);
1472 end if;
1473 end Freeze_Before;
1474
1475 -------------------
1476 -- Freeze_Entity --
1477 -------------------
1478
1479 function Freeze_Entity (E : Entity_Id; Loc : Source_Ptr) return List_Id is
1480 Test_E : Entity_Id := E;
1481 Comp : Entity_Id;
1482 F_Node : Node_Id;
1483 Result : List_Id;
1484 Indx : Node_Id;
1485 Formal : Entity_Id;
1486 Atype : Entity_Id;
1487
1488 Has_Default_Initialization : Boolean := False;
1489 -- This flag gets set to true for a variable with default initialization
1490
1491 procedure Check_Current_Instance (Comp_Decl : Node_Id);
1492 -- Check that an Access or Unchecked_Access attribute with a prefix
1493 -- which is the current instance type can only be applied when the type
1494 -- is limited.
1495
1496 procedure Check_Suspicious_Modulus (Utype : Entity_Id);
1497 -- Give warning for modulus of 8, 16, 32, or 64 given as an explicit
1498 -- integer literal without an explicit corresponding size clause. The
1499 -- caller has checked that Utype is a modular integer type.
1500
1501 function After_Last_Declaration return Boolean;
1502 -- If Loc is a freeze_entity that appears after the last declaration
1503 -- in the scope, inhibit error messages on late completion.
1504
1505 procedure Freeze_Record_Type (Rec : Entity_Id);
1506 -- Freeze each component, handle some representation clauses, and freeze
1507 -- primitive operations if this is a tagged type.
1508
1509 ----------------------------
1510 -- After_Last_Declaration --
1511 ----------------------------
1512
1513 function After_Last_Declaration return Boolean is
1514 Spec : constant Node_Id := Parent (Current_Scope);
1515 begin
1516 if Nkind (Spec) = N_Package_Specification then
1517 if Present (Private_Declarations (Spec)) then
1518 return Loc >= Sloc (Last (Private_Declarations (Spec)));
1519 elsif Present (Visible_Declarations (Spec)) then
1520 return Loc >= Sloc (Last (Visible_Declarations (Spec)));
1521 else
1522 return False;
1523 end if;
1524 else
1525 return False;
1526 end if;
1527 end After_Last_Declaration;
1528
1529 ----------------------------
1530 -- Check_Current_Instance --
1531 ----------------------------
1532
1533 procedure Check_Current_Instance (Comp_Decl : Node_Id) is
1534
1535 Rec_Type : constant Entity_Id :=
1536 Scope (Defining_Identifier (Comp_Decl));
1537
1538 Decl : constant Node_Id := Parent (Rec_Type);
1539
1540 function Process (N : Node_Id) return Traverse_Result;
1541 -- Process routine to apply check to given node
1542
1543 -------------
1544 -- Process --
1545 -------------
1546
1547 function Process (N : Node_Id) return Traverse_Result is
1548 begin
1549 case Nkind (N) is
1550 when N_Attribute_Reference =>
1551 if (Attribute_Name (N) = Name_Access
1552 or else
1553 Attribute_Name (N) = Name_Unchecked_Access)
1554 and then Is_Entity_Name (Prefix (N))
1555 and then Is_Type (Entity (Prefix (N)))
1556 and then Entity (Prefix (N)) = E
1557 then
1558 Error_Msg_N
1559 ("current instance must be a limited type", Prefix (N));
1560 return Abandon;
1561 else
1562 return OK;
1563 end if;
1564
1565 when others => return OK;
1566 end case;
1567 end Process;
1568
1569 procedure Traverse is new Traverse_Proc (Process);
1570
1571 -- Start of processing for Check_Current_Instance
1572
1573 begin
1574 -- In Ada95, the (imprecise) rule is that the current instance of a
1575 -- limited type is aliased. In Ada2005, limitedness must be explicit:
1576 -- either a tagged type, or a limited record.
1577
1578 if Is_Limited_Type (Rec_Type)
1579 and then (Ada_Version < Ada_2005 or else Is_Tagged_Type (Rec_Type))
1580 then
1581 return;
1582
1583 elsif Nkind (Decl) = N_Full_Type_Declaration
1584 and then Limited_Present (Type_Definition (Decl))
1585 then
1586 return;
1587
1588 else
1589 Traverse (Comp_Decl);
1590 end if;
1591 end Check_Current_Instance;
1592
1593 ------------------------------
1594 -- Check_Suspicious_Modulus --
1595 ------------------------------
1596
1597 procedure Check_Suspicious_Modulus (Utype : Entity_Id) is
1598 Decl : constant Node_Id := Declaration_Node (Underlying_Type (Utype));
1599
1600 begin
1601 if Nkind (Decl) = N_Full_Type_Declaration then
1602 declare
1603 Tdef : constant Node_Id := Type_Definition (Decl);
1604 begin
1605 if Nkind (Tdef) = N_Modular_Type_Definition then
1606 declare
1607 Modulus : constant Node_Id :=
1608 Original_Node (Expression (Tdef));
1609 begin
1610 if Nkind (Modulus) = N_Integer_Literal then
1611 declare
1612 Modv : constant Uint := Intval (Modulus);
1613 Sizv : constant Uint := RM_Size (Utype);
1614
1615 begin
1616 -- First case, modulus and size are the same. This
1617 -- happens if you have something like mod 32, with
1618 -- an explicit size of 32, this is for sure a case
1619 -- where the warning is given, since it is seems
1620 -- very unlikely that someone would want e.g. a
1621 -- five bit type stored in 32 bits. It is much
1622 -- more likely they wanted a 32-bit type.
1623
1624 if Modv = Sizv then
1625 null;
1626
1627 -- Second case, the modulus is 32 or 64 and no
1628 -- size clause is present. This is a less clear
1629 -- case for giving the warning, but in the case
1630 -- of 32/64 (5-bit or 6-bit types) these seem rare
1631 -- enough that it is a likely error (and in any
1632 -- case using 2**5 or 2**6 in these cases seems
1633 -- clearer. We don't include 8 or 16 here, simply
1634 -- because in practice 3-bit and 4-bit types are
1635 -- more common and too many false positives if
1636 -- we warn in these cases.
1637
1638 elsif not Has_Size_Clause (Utype)
1639 and then (Modv = Uint_32 or else Modv = Uint_64)
1640 then
1641 null;
1642
1643 -- No warning needed
1644
1645 else
1646 return;
1647 end if;
1648
1649 -- If we fall through, give warning
1650
1651 Error_Msg_Uint_1 := Modv;
1652 Error_Msg_N
1653 ("?2 '*'*^' may have been intended here",
1654 Modulus);
1655 end;
1656 end if;
1657 end;
1658 end if;
1659 end;
1660 end if;
1661 end Check_Suspicious_Modulus;
1662
1663 ------------------------
1664 -- Freeze_Record_Type --
1665 ------------------------
1666
1667 procedure Freeze_Record_Type (Rec : Entity_Id) is
1668 Comp : Entity_Id;
1669 IR : Node_Id;
1670 ADC : Node_Id;
1671 Prev : Entity_Id;
1672
1673 Junk : Boolean;
1674 pragma Warnings (Off, Junk);
1675
1676 Unplaced_Component : Boolean := False;
1677 -- Set True if we find at least one component with no component
1678 -- clause (used to warn about useless Pack pragmas).
1679
1680 Placed_Component : Boolean := False;
1681 -- Set True if we find at least one component with a component
1682 -- clause (used to warn about useless Bit_Order pragmas, and also
1683 -- to detect cases where Implicit_Packing may have an effect).
1684
1685 All_Scalar_Components : Boolean := True;
1686 -- Set False if we encounter a component of a non-scalar type
1687
1688 Scalar_Component_Total_RM_Size : Uint := Uint_0;
1689 Scalar_Component_Total_Esize : Uint := Uint_0;
1690 -- Accumulates total RM_Size values and total Esize values of all
1691 -- scalar components. Used for processing of Implicit_Packing.
1692
1693 function Check_Allocator (N : Node_Id) return Node_Id;
1694 -- If N is an allocator, possibly wrapped in one or more level of
1695 -- qualified expression(s), return the inner allocator node, else
1696 -- return Empty.
1697
1698 procedure Check_Itype (Typ : Entity_Id);
1699 -- If the component subtype is an access to a constrained subtype of
1700 -- an already frozen type, make the subtype frozen as well. It might
1701 -- otherwise be frozen in the wrong scope, and a freeze node on
1702 -- subtype has no effect. Similarly, if the component subtype is a
1703 -- regular (not protected) access to subprogram, set the anonymous
1704 -- subprogram type to frozen as well, to prevent an out-of-scope
1705 -- freeze node at some eventual point of call. Protected operations
1706 -- are handled elsewhere.
1707
1708 ---------------------
1709 -- Check_Allocator --
1710 ---------------------
1711
1712 function Check_Allocator (N : Node_Id) return Node_Id is
1713 Inner : Node_Id;
1714 begin
1715 Inner := N;
1716 loop
1717 if Nkind (Inner) = N_Allocator then
1718 return Inner;
1719 elsif Nkind (Inner) = N_Qualified_Expression then
1720 Inner := Expression (Inner);
1721 else
1722 return Empty;
1723 end if;
1724 end loop;
1725 end Check_Allocator;
1726
1727 -----------------
1728 -- Check_Itype --
1729 -----------------
1730
1731 procedure Check_Itype (Typ : Entity_Id) is
1732 Desig : constant Entity_Id := Designated_Type (Typ);
1733
1734 begin
1735 if not Is_Frozen (Desig)
1736 and then Is_Frozen (Base_Type (Desig))
1737 then
1738 Set_Is_Frozen (Desig);
1739
1740 -- In addition, add an Itype_Reference to ensure that the
1741 -- access subtype is elaborated early enough. This cannot be
1742 -- done if the subtype may depend on discriminants.
1743
1744 if Ekind (Comp) = E_Component
1745 and then Is_Itype (Etype (Comp))
1746 and then not Has_Discriminants (Rec)
1747 then
1748 IR := Make_Itype_Reference (Sloc (Comp));
1749 Set_Itype (IR, Desig);
1750
1751 if No (Result) then
1752 Result := New_List (IR);
1753 else
1754 Append (IR, Result);
1755 end if;
1756 end if;
1757
1758 elsif Ekind (Typ) = E_Anonymous_Access_Subprogram_Type
1759 and then Convention (Desig) /= Convention_Protected
1760 then
1761 Set_Is_Frozen (Desig);
1762 end if;
1763 end Check_Itype;
1764
1765 -- Start of processing for Freeze_Record_Type
1766
1767 begin
1768 -- If this is a subtype of a controlled type, declared without a
1769 -- constraint, the _controller may not appear in the component list
1770 -- if the parent was not frozen at the point of subtype declaration.
1771 -- Inherit the _controller component now.
1772
1773 if Rec /= Base_Type (Rec)
1774 and then Has_Controlled_Component (Rec)
1775 then
1776 if Nkind (Parent (Rec)) = N_Subtype_Declaration
1777 and then Is_Entity_Name (Subtype_Indication (Parent (Rec)))
1778 then
1779 Set_First_Entity (Rec, First_Entity (Base_Type (Rec)));
1780
1781 -- If this is an internal type without a declaration, as for
1782 -- record component, the base type may not yet be frozen, and its
1783 -- controller has not been created. Add an explicit freeze node
1784 -- for the itype, so it will be frozen after the base type. This
1785 -- freeze node is used to communicate with the expander, in order
1786 -- to create the controller for the enclosing record, and it is
1787 -- deleted afterwards (see exp_ch3). It must not be created when
1788 -- expansion is off, because it might appear in the wrong context
1789 -- for the back end.
1790
1791 elsif Is_Itype (Rec)
1792 and then Has_Delayed_Freeze (Base_Type (Rec))
1793 and then
1794 Nkind (Associated_Node_For_Itype (Rec)) =
1795 N_Component_Declaration
1796 and then Expander_Active
1797 then
1798 Ensure_Freeze_Node (Rec);
1799 end if;
1800 end if;
1801
1802 -- Freeze components and embedded subtypes
1803
1804 Comp := First_Entity (Rec);
1805 Prev := Empty;
1806 while Present (Comp) loop
1807
1808 -- First handle the component case
1809
1810 if Ekind (Comp) = E_Component
1811 or else Ekind (Comp) = E_Discriminant
1812 then
1813 declare
1814 CC : constant Node_Id := Component_Clause (Comp);
1815
1816 begin
1817 -- Freezing a record type freezes the type of each of its
1818 -- components. However, if the type of the component is
1819 -- part of this record, we do not want or need a separate
1820 -- Freeze_Node. Note that Is_Itype is wrong because that's
1821 -- also set in private type cases. We also can't check for
1822 -- the Scope being exactly Rec because of private types and
1823 -- record extensions.
1824
1825 if Is_Itype (Etype (Comp))
1826 and then Is_Record_Type (Underlying_Type
1827 (Scope (Etype (Comp))))
1828 then
1829 Undelay_Type (Etype (Comp));
1830 end if;
1831
1832 Freeze_And_Append (Etype (Comp), Loc, Result);
1833
1834 -- Check for error of component clause given for variable
1835 -- sized type. We have to delay this test till this point,
1836 -- since the component type has to be frozen for us to know
1837 -- if it is variable length. We omit this test in a generic
1838 -- context, it will be applied at instantiation time.
1839
1840 if Present (CC) then
1841 Placed_Component := True;
1842
1843 if Inside_A_Generic then
1844 null;
1845
1846 elsif not
1847 Size_Known_At_Compile_Time
1848 (Underlying_Type (Etype (Comp)))
1849 then
1850 Error_Msg_N
1851 ("component clause not allowed for variable " &
1852 "length component", CC);
1853 end if;
1854
1855 else
1856 Unplaced_Component := True;
1857 end if;
1858
1859 -- Case of component requires byte alignment
1860
1861 if Must_Be_On_Byte_Boundary (Etype (Comp)) then
1862
1863 -- Set the enclosing record to also require byte align
1864
1865 Set_Must_Be_On_Byte_Boundary (Rec);
1866
1867 -- Check for component clause that is inconsistent with
1868 -- the required byte boundary alignment.
1869
1870 if Present (CC)
1871 and then Normalized_First_Bit (Comp) mod
1872 System_Storage_Unit /= 0
1873 then
1874 Error_Msg_N
1875 ("component & must be byte aligned",
1876 Component_Name (Component_Clause (Comp)));
1877 end if;
1878 end if;
1879 end;
1880 end if;
1881
1882 -- Gather data for possible Implicit_Packing later. Note that at
1883 -- this stage we might be dealing with a real component, or with
1884 -- an implicit subtype declaration.
1885
1886 if not Is_Scalar_Type (Etype (Comp)) then
1887 All_Scalar_Components := False;
1888 else
1889 Scalar_Component_Total_RM_Size :=
1890 Scalar_Component_Total_RM_Size + RM_Size (Etype (Comp));
1891 Scalar_Component_Total_Esize :=
1892 Scalar_Component_Total_Esize + Esize (Etype (Comp));
1893 end if;
1894
1895 -- If the component is an Itype with Delayed_Freeze and is either
1896 -- a record or array subtype and its base type has not yet been
1897 -- frozen, we must remove this from the entity list of this record
1898 -- and put it on the entity list of the scope of its base type.
1899 -- Note that we know that this is not the type of a component
1900 -- since we cleared Has_Delayed_Freeze for it in the previous
1901 -- loop. Thus this must be the Designated_Type of an access type,
1902 -- which is the type of a component.
1903
1904 if Is_Itype (Comp)
1905 and then Is_Type (Scope (Comp))
1906 and then Is_Composite_Type (Comp)
1907 and then Base_Type (Comp) /= Comp
1908 and then Has_Delayed_Freeze (Comp)
1909 and then not Is_Frozen (Base_Type (Comp))
1910 then
1911 declare
1912 Will_Be_Frozen : Boolean := False;
1913 S : Entity_Id;
1914
1915 begin
1916 -- We have a pretty bad kludge here. Suppose Rec is subtype
1917 -- being defined in a subprogram that's created as part of
1918 -- the freezing of Rec'Base. In that case, we know that
1919 -- Comp'Base must have already been frozen by the time we
1920 -- get to elaborate this because Gigi doesn't elaborate any
1921 -- bodies until it has elaborated all of the declarative
1922 -- part. But Is_Frozen will not be set at this point because
1923 -- we are processing code in lexical order.
1924
1925 -- We detect this case by going up the Scope chain of Rec
1926 -- and seeing if we have a subprogram scope before reaching
1927 -- the top of the scope chain or that of Comp'Base. If we
1928 -- do, then mark that Comp'Base will actually be frozen. If
1929 -- so, we merely undelay it.
1930
1931 S := Scope (Rec);
1932 while Present (S) loop
1933 if Is_Subprogram (S) then
1934 Will_Be_Frozen := True;
1935 exit;
1936 elsif S = Scope (Base_Type (Comp)) then
1937 exit;
1938 end if;
1939
1940 S := Scope (S);
1941 end loop;
1942
1943 if Will_Be_Frozen then
1944 Undelay_Type (Comp);
1945 else
1946 if Present (Prev) then
1947 Set_Next_Entity (Prev, Next_Entity (Comp));
1948 else
1949 Set_First_Entity (Rec, Next_Entity (Comp));
1950 end if;
1951
1952 -- Insert in entity list of scope of base type (which
1953 -- must be an enclosing scope, because still unfrozen).
1954
1955 Append_Entity (Comp, Scope (Base_Type (Comp)));
1956 end if;
1957 end;
1958
1959 -- If the component is an access type with an allocator as default
1960 -- value, the designated type will be frozen by the corresponding
1961 -- expression in init_proc. In order to place the freeze node for
1962 -- the designated type before that for the current record type,
1963 -- freeze it now.
1964
1965 -- Same process if the component is an array of access types,
1966 -- initialized with an aggregate. If the designated type is
1967 -- private, it cannot contain allocators, and it is premature
1968 -- to freeze the type, so we check for this as well.
1969
1970 elsif Is_Access_Type (Etype (Comp))
1971 and then Present (Parent (Comp))
1972 and then Present (Expression (Parent (Comp)))
1973 then
1974 declare
1975 Alloc : constant Node_Id :=
1976 Check_Allocator (Expression (Parent (Comp)));
1977
1978 begin
1979 if Present (Alloc) then
1980
1981 -- If component is pointer to a classwide type, freeze
1982 -- the specific type in the expression being allocated.
1983 -- The expression may be a subtype indication, in which
1984 -- case freeze the subtype mark.
1985
1986 if Is_Class_Wide_Type
1987 (Designated_Type (Etype (Comp)))
1988 then
1989 if Is_Entity_Name (Expression (Alloc)) then
1990 Freeze_And_Append
1991 (Entity (Expression (Alloc)), Loc, Result);
1992 elsif
1993 Nkind (Expression (Alloc)) = N_Subtype_Indication
1994 then
1995 Freeze_And_Append
1996 (Entity (Subtype_Mark (Expression (Alloc))),
1997 Loc, Result);
1998 end if;
1999
2000 elsif Is_Itype (Designated_Type (Etype (Comp))) then
2001 Check_Itype (Etype (Comp));
2002
2003 else
2004 Freeze_And_Append
2005 (Designated_Type (Etype (Comp)), Loc, Result);
2006 end if;
2007 end if;
2008 end;
2009
2010 elsif Is_Access_Type (Etype (Comp))
2011 and then Is_Itype (Designated_Type (Etype (Comp)))
2012 then
2013 Check_Itype (Etype (Comp));
2014
2015 elsif Is_Array_Type (Etype (Comp))
2016 and then Is_Access_Type (Component_Type (Etype (Comp)))
2017 and then Present (Parent (Comp))
2018 and then Nkind (Parent (Comp)) = N_Component_Declaration
2019 and then Present (Expression (Parent (Comp)))
2020 and then Nkind (Expression (Parent (Comp))) = N_Aggregate
2021 and then Is_Fully_Defined
2022 (Designated_Type (Component_Type (Etype (Comp))))
2023 then
2024 Freeze_And_Append
2025 (Designated_Type
2026 (Component_Type (Etype (Comp))), Loc, Result);
2027 end if;
2028
2029 Prev := Comp;
2030 Next_Entity (Comp);
2031 end loop;
2032
2033 -- Deal with pragma Bit_Order setting non-standard bit order
2034
2035 if Reverse_Bit_Order (Rec) and then Base_Type (Rec) = Rec then
2036 if not Placed_Component then
2037 ADC :=
2038 Get_Attribute_Definition_Clause (Rec, Attribute_Bit_Order);
2039 Error_Msg_N ("?Bit_Order specification has no effect", ADC);
2040 Error_Msg_N
2041 ("\?since no component clauses were specified", ADC);
2042
2043 -- Here is where we do the processing for reversed bit order
2044
2045 else
2046 Adjust_Record_For_Reverse_Bit_Order (Rec);
2047 end if;
2048 end if;
2049
2050 -- Complete error checking on record representation clause (e.g.
2051 -- overlap of components). This is called after adjusting the
2052 -- record for reverse bit order.
2053
2054 declare
2055 RRC : constant Node_Id := Get_Record_Representation_Clause (Rec);
2056 begin
2057 if Present (RRC) then
2058 Check_Record_Representation_Clause (RRC);
2059 end if;
2060 end;
2061
2062 -- Set OK_To_Reorder_Components depending on debug flags
2063
2064 if Rec = Base_Type (Rec)
2065 and then Convention (Rec) = Convention_Ada
2066 then
2067 if (Has_Discriminants (Rec) and then Debug_Flag_Dot_V)
2068 or else
2069 (not Has_Discriminants (Rec) and then Debug_Flag_Dot_R)
2070 then
2071 Set_OK_To_Reorder_Components (Rec);
2072 end if;
2073 end if;
2074
2075 -- Check for useless pragma Pack when all components placed. We only
2076 -- do this check for record types, not subtypes, since a subtype may
2077 -- have all its components placed, and it still makes perfectly good
2078 -- sense to pack other subtypes or the parent type. We do not give
2079 -- this warning if Optimize_Alignment is set to Space, since the
2080 -- pragma Pack does have an effect in this case (it always resets
2081 -- the alignment to one).
2082
2083 if Ekind (Rec) = E_Record_Type
2084 and then Is_Packed (Rec)
2085 and then not Unplaced_Component
2086 and then Optimize_Alignment /= 'S'
2087 then
2088 -- Reset packed status. Probably not necessary, but we do it so
2089 -- that there is no chance of the back end doing something strange
2090 -- with this redundant indication of packing.
2091
2092 Set_Is_Packed (Rec, False);
2093
2094 -- Give warning if redundant constructs warnings on
2095
2096 if Warn_On_Redundant_Constructs then
2097 Error_Msg_N -- CODEFIX
2098 ("?pragma Pack has no effect, no unplaced components",
2099 Get_Rep_Pragma (Rec, Name_Pack));
2100 end if;
2101 end if;
2102
2103 -- If this is the record corresponding to a remote type, freeze the
2104 -- remote type here since that is what we are semantically freezing.
2105 -- This prevents the freeze node for that type in an inner scope.
2106
2107 -- Also, Check for controlled components and unchecked unions.
2108 -- Finally, enforce the restriction that access attributes with a
2109 -- current instance prefix can only apply to limited types.
2110
2111 if Ekind (Rec) = E_Record_Type then
2112 if Present (Corresponding_Remote_Type (Rec)) then
2113 Freeze_And_Append
2114 (Corresponding_Remote_Type (Rec), Loc, Result);
2115 end if;
2116
2117 Comp := First_Component (Rec);
2118 while Present (Comp) loop
2119
2120 -- Do not set Has_Controlled_Component on a class-wide
2121 -- equivalent type. See Make_CW_Equivalent_Type.
2122
2123 if not Is_Class_Wide_Equivalent_Type (Rec)
2124 and then (Has_Controlled_Component (Etype (Comp))
2125 or else (Chars (Comp) /= Name_uParent
2126 and then Is_Controlled (Etype (Comp)))
2127 or else (Is_Protected_Type (Etype (Comp))
2128 and then Present
2129 (Corresponding_Record_Type
2130 (Etype (Comp)))
2131 and then Has_Controlled_Component
2132 (Corresponding_Record_Type
2133 (Etype (Comp)))))
2134 then
2135 Set_Has_Controlled_Component (Rec);
2136 exit;
2137 end if;
2138
2139 if Has_Unchecked_Union (Etype (Comp)) then
2140 Set_Has_Unchecked_Union (Rec);
2141 end if;
2142
2143 if Has_Per_Object_Constraint (Comp) then
2144
2145 -- Scan component declaration for likely misuses of current
2146 -- instance, either in a constraint or a default expression.
2147
2148 Check_Current_Instance (Parent (Comp));
2149 end if;
2150
2151 Next_Component (Comp);
2152 end loop;
2153 end if;
2154
2155 Set_Component_Alignment_If_Not_Set (Rec);
2156
2157 -- For first subtypes, check if there are any fixed-point fields with
2158 -- component clauses, where we must check the size. This is not done
2159 -- till the freeze point, since for fixed-point types, we do not know
2160 -- the size until the type is frozen. Similar processing applies to
2161 -- bit packed arrays.
2162
2163 if Is_First_Subtype (Rec) then
2164 Comp := First_Component (Rec);
2165 while Present (Comp) loop
2166 if Present (Component_Clause (Comp))
2167 and then (Is_Fixed_Point_Type (Etype (Comp))
2168 or else
2169 Is_Bit_Packed_Array (Etype (Comp)))
2170 then
2171 Check_Size
2172 (Component_Name (Component_Clause (Comp)),
2173 Etype (Comp),
2174 Esize (Comp),
2175 Junk);
2176 end if;
2177
2178 Next_Component (Comp);
2179 end loop;
2180 end if;
2181
2182 -- Generate warning for applying C or C++ convention to a record
2183 -- with discriminants. This is suppressed for the unchecked union
2184 -- case, since the whole point in this case is interface C. We also
2185 -- do not generate this within instantiations, since we will have
2186 -- generated a message on the template.
2187
2188 if Has_Discriminants (E)
2189 and then not Is_Unchecked_Union (E)
2190 and then (Convention (E) = Convention_C
2191 or else
2192 Convention (E) = Convention_CPP)
2193 and then Comes_From_Source (E)
2194 and then not In_Instance
2195 and then not Has_Warnings_Off (E)
2196 and then not Has_Warnings_Off (Base_Type (E))
2197 then
2198 declare
2199 Cprag : constant Node_Id := Get_Rep_Pragma (E, Name_Convention);
2200 A2 : Node_Id;
2201
2202 begin
2203 if Present (Cprag) then
2204 A2 := Next (First (Pragma_Argument_Associations (Cprag)));
2205
2206 if Convention (E) = Convention_C then
2207 Error_Msg_N
2208 ("?variant record has no direct equivalent in C", A2);
2209 else
2210 Error_Msg_N
2211 ("?variant record has no direct equivalent in C++", A2);
2212 end if;
2213
2214 Error_Msg_NE
2215 ("\?use of convention for type& is dubious", A2, E);
2216 end if;
2217 end;
2218 end if;
2219
2220 -- See if Size is too small as is (and implicit packing might help)
2221
2222 if not Is_Packed (Rec)
2223
2224 -- No implicit packing if even one component is explicitly placed
2225
2226 and then not Placed_Component
2227
2228 -- Must have size clause and all scalar components
2229
2230 and then Has_Size_Clause (Rec)
2231 and then All_Scalar_Components
2232
2233 -- Do not try implicit packing on records with discriminants, too
2234 -- complicated, especially in the variant record case.
2235
2236 and then not Has_Discriminants (Rec)
2237
2238 -- We can implicitly pack if the specified size of the record is
2239 -- less than the sum of the object sizes (no point in packing if
2240 -- this is not the case).
2241
2242 and then Esize (Rec) < Scalar_Component_Total_Esize
2243
2244 -- And the total RM size cannot be greater than the specified size
2245 -- since otherwise packing will not get us where we have to be!
2246
2247 and then Esize (Rec) >= Scalar_Component_Total_RM_Size
2248
2249 -- Never do implicit packing in CodePeer mode since we don't do
2250 -- any packing in this mode, since this generates over-complex
2251 -- code that confuses CodePeer, and in general, CodePeer does not
2252 -- care about the internal representation of objects.
2253
2254 and then not CodePeer_Mode
2255 then
2256 -- If implicit packing enabled, do it
2257
2258 if Implicit_Packing then
2259 Set_Is_Packed (Rec);
2260
2261 -- Otherwise flag the size clause
2262
2263 else
2264 declare
2265 Sz : constant Node_Id := Size_Clause (Rec);
2266 begin
2267 Error_Msg_NE -- CODEFIX
2268 ("size given for& too small", Sz, Rec);
2269 Error_Msg_N -- CODEFIX
2270 ("\use explicit pragma Pack "
2271 & "or use pragma Implicit_Packing", Sz);
2272 end;
2273 end if;
2274 end if;
2275 end Freeze_Record_Type;
2276
2277 -- Start of processing for Freeze_Entity
2278
2279 begin
2280 -- We are going to test for various reasons why this entity need not be
2281 -- frozen here, but in the case of an Itype that's defined within a
2282 -- record, that test actually applies to the record.
2283
2284 if Is_Itype (E) and then Is_Record_Type (Scope (E)) then
2285 Test_E := Scope (E);
2286 elsif Is_Itype (E) and then Present (Underlying_Type (Scope (E)))
2287 and then Is_Record_Type (Underlying_Type (Scope (E)))
2288 then
2289 Test_E := Underlying_Type (Scope (E));
2290 end if;
2291
2292 -- Do not freeze if already frozen since we only need one freeze node
2293
2294 if Is_Frozen (E) then
2295 return No_List;
2296
2297 -- It is improper to freeze an external entity within a generic because
2298 -- its freeze node will appear in a non-valid context. The entity will
2299 -- be frozen in the proper scope after the current generic is analyzed.
2300
2301 elsif Inside_A_Generic and then External_Ref_In_Generic (Test_E) then
2302 return No_List;
2303
2304 -- Do not freeze a global entity within an inner scope created during
2305 -- expansion. A call to subprogram E within some internal procedure
2306 -- (a stream attribute for example) might require freezing E, but the
2307 -- freeze node must appear in the same declarative part as E itself.
2308 -- The two-pass elaboration mechanism in gigi guarantees that E will
2309 -- be frozen before the inner call is elaborated. We exclude constants
2310 -- from this test, because deferred constants may be frozen early, and
2311 -- must be diagnosed (e.g. in the case of a deferred constant being used
2312 -- in a default expression). If the enclosing subprogram comes from
2313 -- source, or is a generic instance, then the freeze point is the one
2314 -- mandated by the language, and we freeze the entity. A subprogram that
2315 -- is a child unit body that acts as a spec does not have a spec that
2316 -- comes from source, but can only come from source.
2317
2318 elsif In_Open_Scopes (Scope (Test_E))
2319 and then Scope (Test_E) /= Current_Scope
2320 and then Ekind (Test_E) /= E_Constant
2321 then
2322 declare
2323 S : Entity_Id;
2324
2325 begin
2326 S := Current_Scope;
2327 while Present (S) loop
2328 if Is_Overloadable (S) then
2329 if Comes_From_Source (S)
2330 or else Is_Generic_Instance (S)
2331 or else Is_Child_Unit (S)
2332 then
2333 exit;
2334 else
2335 return No_List;
2336 end if;
2337 end if;
2338
2339 S := Scope (S);
2340 end loop;
2341 end;
2342
2343 -- Similarly, an inlined instance body may make reference to global
2344 -- entities, but these references cannot be the proper freezing point
2345 -- for them, and in the absence of inlining freezing will take place in
2346 -- their own scope. Normally instance bodies are analyzed after the
2347 -- enclosing compilation, and everything has been frozen at the proper
2348 -- place, but with front-end inlining an instance body is compiled
2349 -- before the end of the enclosing scope, and as a result out-of-order
2350 -- freezing must be prevented.
2351
2352 elsif Front_End_Inlining
2353 and then In_Instance_Body
2354 and then Present (Scope (Test_E))
2355 then
2356 declare
2357 S : Entity_Id;
2358
2359 begin
2360 S := Scope (Test_E);
2361 while Present (S) loop
2362 if Is_Generic_Instance (S) then
2363 exit;
2364 else
2365 S := Scope (S);
2366 end if;
2367 end loop;
2368
2369 if No (S) then
2370 return No_List;
2371 end if;
2372 end;
2373 end if;
2374
2375 -- Here to freeze the entity
2376
2377 Result := No_List;
2378 Set_Is_Frozen (E);
2379
2380 -- Case of entity being frozen is other than a type
2381
2382 if not Is_Type (E) then
2383
2384 -- If entity is exported or imported and does not have an external
2385 -- name, now is the time to provide the appropriate default name.
2386 -- Skip this if the entity is stubbed, since we don't need a name
2387 -- for any stubbed routine. For the case on intrinsics, if no
2388 -- external name is specified, then calls will be handled in
2389 -- Exp_Intr.Expand_Intrinsic_Call, and no name is needed. If an
2390 -- external name is provided, then Expand_Intrinsic_Call leaves
2391 -- calls in place for expansion by GIGI.
2392
2393 if (Is_Imported (E) or else Is_Exported (E))
2394 and then No (Interface_Name (E))
2395 and then Convention (E) /= Convention_Stubbed
2396 and then Convention (E) /= Convention_Intrinsic
2397 then
2398 Set_Encoded_Interface_Name
2399 (E, Get_Default_External_Name (E));
2400
2401 -- If entity is an atomic object appearing in a declaration and
2402 -- the expression is an aggregate, assign it to a temporary to
2403 -- ensure that the actual assignment is done atomically rather
2404 -- than component-wise (the assignment to the temp may be done
2405 -- component-wise, but that is harmless).
2406
2407 elsif Is_Atomic (E)
2408 and then Nkind (Parent (E)) = N_Object_Declaration
2409 and then Present (Expression (Parent (E)))
2410 and then Nkind (Expression (Parent (E))) = N_Aggregate
2411 and then
2412 Is_Atomic_Aggregate (Expression (Parent (E)), Etype (E))
2413 then
2414 null;
2415 end if;
2416
2417 -- For a subprogram, freeze all parameter types and also the return
2418 -- type (RM 13.14(14)). However skip this for internal subprograms.
2419 -- This is also the point where any extra formal parameters are
2420 -- created since we now know whether the subprogram will use a
2421 -- foreign convention.
2422
2423 if Is_Subprogram (E) then
2424 if not Is_Internal (E) then
2425 declare
2426 F_Type : Entity_Id;
2427 R_Type : Entity_Id;
2428 Warn_Node : Node_Id;
2429
2430 begin
2431 -- Loop through formals
2432
2433 Formal := First_Formal (E);
2434 while Present (Formal) loop
2435 F_Type := Etype (Formal);
2436 Freeze_And_Append (F_Type, Loc, Result);
2437
2438 if Is_Private_Type (F_Type)
2439 and then Is_Private_Type (Base_Type (F_Type))
2440 and then No (Full_View (Base_Type (F_Type)))
2441 and then not Is_Generic_Type (F_Type)
2442 and then not Is_Derived_Type (F_Type)
2443 then
2444 -- If the type of a formal is incomplete, subprogram
2445 -- is being frozen prematurely. Within an instance
2446 -- (but not within a wrapper package) this is an
2447 -- artifact of our need to regard the end of an
2448 -- instantiation as a freeze point. Otherwise it is
2449 -- a definite error.
2450
2451 if In_Instance then
2452 Set_Is_Frozen (E, False);
2453 return No_List;
2454
2455 elsif not After_Last_Declaration
2456 and then not Freezing_Library_Level_Tagged_Type
2457 then
2458 Error_Msg_Node_1 := F_Type;
2459 Error_Msg
2460 ("type& must be fully defined before this point",
2461 Loc);
2462 end if;
2463 end if;
2464
2465 -- Check suspicious parameter for C function. These tests
2466 -- apply only to exported/imported subprograms.
2467
2468 if Warn_On_Export_Import
2469 and then Comes_From_Source (E)
2470 and then (Convention (E) = Convention_C
2471 or else
2472 Convention (E) = Convention_CPP)
2473 and then (Is_Imported (E) or else Is_Exported (E))
2474 and then Convention (E) /= Convention (Formal)
2475 and then not Has_Warnings_Off (E)
2476 and then not Has_Warnings_Off (F_Type)
2477 and then not Has_Warnings_Off (Formal)
2478 then
2479 -- Qualify mention of formals with subprogram name
2480
2481 Error_Msg_Qual_Level := 1;
2482
2483 -- Check suspicious use of fat C pointer
2484
2485 if Is_Access_Type (F_Type)
2486 and then Esize (F_Type) > Ttypes.System_Address_Size
2487 then
2488 Error_Msg_N
2489 ("?type of & does not correspond to C pointer!",
2490 Formal);
2491
2492 -- Check suspicious return of boolean
2493
2494 elsif Root_Type (F_Type) = Standard_Boolean
2495 and then Convention (F_Type) = Convention_Ada
2496 and then not Has_Warnings_Off (F_Type)
2497 and then not Has_Size_Clause (F_Type)
2498 and then VM_Target = No_VM
2499 then
2500 Error_Msg_N ("& is an 8-bit Ada Boolean?", Formal);
2501 Error_Msg_N
2502 ("\use appropriate corresponding type in C "
2503 & "(e.g. char)?", Formal);
2504
2505 -- Check suspicious tagged type
2506
2507 elsif (Is_Tagged_Type (F_Type)
2508 or else (Is_Access_Type (F_Type)
2509 and then
2510 Is_Tagged_Type
2511 (Designated_Type (F_Type))))
2512 and then Convention (E) = Convention_C
2513 then
2514 Error_Msg_N
2515 ("?& involves a tagged type which does not "
2516 & "correspond to any C type!", Formal);
2517
2518 -- Check wrong convention subprogram pointer
2519
2520 elsif Ekind (F_Type) = E_Access_Subprogram_Type
2521 and then not Has_Foreign_Convention (F_Type)
2522 then
2523 Error_Msg_N
2524 ("?subprogram pointer & should "
2525 & "have foreign convention!", Formal);
2526 Error_Msg_Sloc := Sloc (F_Type);
2527 Error_Msg_NE
2528 ("\?add Convention pragma to declaration of &#",
2529 Formal, F_Type);
2530 end if;
2531
2532 -- Turn off name qualification after message output
2533
2534 Error_Msg_Qual_Level := 0;
2535 end if;
2536
2537 -- Check for unconstrained array in exported foreign
2538 -- convention case.
2539
2540 if Has_Foreign_Convention (E)
2541 and then not Is_Imported (E)
2542 and then Is_Array_Type (F_Type)
2543 and then not Is_Constrained (F_Type)
2544 and then Warn_On_Export_Import
2545
2546 -- Exclude VM case, since both .NET and JVM can handle
2547 -- unconstrained arrays without a problem.
2548
2549 and then VM_Target = No_VM
2550 then
2551 Error_Msg_Qual_Level := 1;
2552
2553 -- If this is an inherited operation, place the
2554 -- warning on the derived type declaration, rather
2555 -- than on the original subprogram.
2556
2557 if Nkind (Original_Node (Parent (E))) =
2558 N_Full_Type_Declaration
2559 then
2560 Warn_Node := Parent (E);
2561
2562 if Formal = First_Formal (E) then
2563 Error_Msg_NE
2564 ("?in inherited operation&", Warn_Node, E);
2565 end if;
2566 else
2567 Warn_Node := Formal;
2568 end if;
2569
2570 Error_Msg_NE
2571 ("?type of argument& is unconstrained array",
2572 Warn_Node, Formal);
2573 Error_Msg_NE
2574 ("?foreign caller must pass bounds explicitly",
2575 Warn_Node, Formal);
2576 Error_Msg_Qual_Level := 0;
2577 end if;
2578
2579 if not From_With_Type (F_Type) then
2580 if Is_Access_Type (F_Type) then
2581 F_Type := Designated_Type (F_Type);
2582 end if;
2583
2584 -- If the formal is an anonymous_access_to_subprogram
2585 -- freeze the subprogram type as well, to prevent
2586 -- scope anomalies in gigi, because there is no other
2587 -- clear point at which it could be frozen.
2588
2589 if Is_Itype (Etype (Formal))
2590 and then Ekind (F_Type) = E_Subprogram_Type
2591 then
2592 Freeze_And_Append (F_Type, Loc, Result);
2593 end if;
2594 end if;
2595
2596 Next_Formal (Formal);
2597 end loop;
2598
2599 -- Case of function: similar checks on return type
2600
2601 if Ekind (E) = E_Function then
2602
2603 -- Freeze return type
2604
2605 R_Type := Etype (E);
2606 Freeze_And_Append (R_Type, Loc, Result);
2607
2608 -- Check suspicious return type for C function
2609
2610 if Warn_On_Export_Import
2611 and then (Convention (E) = Convention_C
2612 or else
2613 Convention (E) = Convention_CPP)
2614 and then (Is_Imported (E) or else Is_Exported (E))
2615 then
2616 -- Check suspicious return of fat C pointer
2617
2618 if Is_Access_Type (R_Type)
2619 and then Esize (R_Type) > Ttypes.System_Address_Size
2620 and then not Has_Warnings_Off (E)
2621 and then not Has_Warnings_Off (R_Type)
2622 then
2623 Error_Msg_N
2624 ("?return type of& does not "
2625 & "correspond to C pointer!", E);
2626
2627 -- Check suspicious return of boolean
2628
2629 elsif Root_Type (R_Type) = Standard_Boolean
2630 and then Convention (R_Type) = Convention_Ada
2631 and then VM_Target = No_VM
2632 and then not Has_Warnings_Off (E)
2633 and then not Has_Warnings_Off (R_Type)
2634 and then not Has_Size_Clause (R_Type)
2635 then
2636 declare
2637 N : constant Node_Id :=
2638 Result_Definition (Declaration_Node (E));
2639 begin
2640 Error_Msg_NE
2641 ("return type of & is an 8-bit Ada Boolean?",
2642 N, E);
2643 Error_Msg_NE
2644 ("\use appropriate corresponding type in C "
2645 & "(e.g. char)?", N, E);
2646 end;
2647
2648 -- Check suspicious return tagged type
2649
2650 elsif (Is_Tagged_Type (R_Type)
2651 or else (Is_Access_Type (R_Type)
2652 and then
2653 Is_Tagged_Type
2654 (Designated_Type (R_Type))))
2655 and then Convention (E) = Convention_C
2656 and then not Has_Warnings_Off (E)
2657 and then not Has_Warnings_Off (R_Type)
2658 then
2659 Error_Msg_N
2660 ("?return type of & does not "
2661 & "correspond to C type!", E);
2662
2663 -- Check return of wrong convention subprogram pointer
2664
2665 elsif Ekind (R_Type) = E_Access_Subprogram_Type
2666 and then not Has_Foreign_Convention (R_Type)
2667 and then not Has_Warnings_Off (E)
2668 and then not Has_Warnings_Off (R_Type)
2669 then
2670 Error_Msg_N
2671 ("?& should return a foreign "
2672 & "convention subprogram pointer", E);
2673 Error_Msg_Sloc := Sloc (R_Type);
2674 Error_Msg_NE
2675 ("\?add Convention pragma to declaration of& #",
2676 E, R_Type);
2677 end if;
2678 end if;
2679
2680 -- Give warning for suspicous return of a result of an
2681 -- unconstrained array type in a foreign convention
2682 -- function.
2683
2684 if Has_Foreign_Convention (E)
2685
2686 -- We are looking for a return of unconstrained array
2687
2688 and then Is_Array_Type (R_Type)
2689 and then not Is_Constrained (R_Type)
2690
2691 -- Exclude imported routines, the warning does not
2692 -- belong on the import, but on the routine definition.
2693
2694 and then not Is_Imported (E)
2695
2696 -- Exclude VM case, since both .NET and JVM can handle
2697 -- return of unconstrained arrays without a problem.
2698
2699 and then VM_Target = No_VM
2700
2701 -- Check that general warning is enabled, and that it
2702 -- is not suppressed for this particular case.
2703
2704 and then Warn_On_Export_Import
2705 and then not Has_Warnings_Off (E)
2706 and then not Has_Warnings_Off (R_Type)
2707 then
2708 Error_Msg_N
2709 ("?foreign convention function& should not " &
2710 "return unconstrained array!", E);
2711 end if;
2712 end if;
2713 end;
2714 end if;
2715
2716 -- Must freeze its parent first if it is a derived subprogram
2717
2718 if Present (Alias (E)) then
2719 Freeze_And_Append (Alias (E), Loc, Result);
2720 end if;
2721
2722 -- We don't freeze internal subprograms, because we don't normally
2723 -- want addition of extra formals or mechanism setting to happen
2724 -- for those. However we do pass through predefined dispatching
2725 -- cases, since extra formals may be needed in some cases, such as
2726 -- for the stream 'Input function (build-in-place formals).
2727
2728 if not Is_Internal (E)
2729 or else Is_Predefined_Dispatching_Operation (E)
2730 then
2731 Freeze_Subprogram (E);
2732 end if;
2733
2734 -- Here for other than a subprogram or type
2735
2736 else
2737 -- If entity has a type, and it is not a generic unit, then
2738 -- freeze it first (RM 13.14(10)).
2739
2740 if Present (Etype (E))
2741 and then Ekind (E) /= E_Generic_Function
2742 then
2743 Freeze_And_Append (Etype (E), Loc, Result);
2744 end if;
2745
2746 -- Special processing for objects created by object declaration
2747
2748 if Nkind (Declaration_Node (E)) = N_Object_Declaration then
2749
2750 -- Abstract type allowed only for C++ imported variables or
2751 -- constants.
2752
2753 -- Note: we inhibit this check for objects that do not come
2754 -- from source because there is at least one case (the
2755 -- expansion of x'class'input where x is abstract) where we
2756 -- legitimately generate an abstract object.
2757
2758 if Is_Abstract_Type (Etype (E))
2759 and then Comes_From_Source (Parent (E))
2760 and then not (Is_Imported (E)
2761 and then Is_CPP_Class (Etype (E)))
2762 then
2763 Error_Msg_N ("type of object cannot be abstract",
2764 Object_Definition (Parent (E)));
2765
2766 if Is_CPP_Class (Etype (E)) then
2767 Error_Msg_NE
2768 ("\} may need a cpp_constructor",
2769 Object_Definition (Parent (E)), Etype (E));
2770 end if;
2771 end if;
2772
2773 -- For object created by object declaration, perform required
2774 -- categorization (preelaborate and pure) checks. Defer these
2775 -- checks to freeze time since pragma Import inhibits default
2776 -- initialization and thus pragma Import affects these checks.
2777
2778 Validate_Object_Declaration (Declaration_Node (E));
2779
2780 -- If there is an address clause, check that it is valid
2781
2782 Check_Address_Clause (E);
2783
2784 -- If the object needs any kind of default initialization, an
2785 -- error must be issued if No_Default_Initialization applies.
2786 -- The check doesn't apply to imported objects, which are not
2787 -- ever default initialized, and is why the check is deferred
2788 -- until freezing, at which point we know if Import applies.
2789 -- Deferred constants are also exempted from this test because
2790 -- their completion is explicit, or through an import pragma.
2791
2792 if Ekind (E) = E_Constant
2793 and then Present (Full_View (E))
2794 then
2795 null;
2796
2797 elsif Comes_From_Source (E)
2798 and then not Is_Imported (E)
2799 and then not Has_Init_Expression (Declaration_Node (E))
2800 and then
2801 ((Has_Non_Null_Base_Init_Proc (Etype (E))
2802 and then not No_Initialization (Declaration_Node (E))
2803 and then not Is_Value_Type (Etype (E))
2804 and then not Suppress_Init_Proc (Etype (E)))
2805 or else
2806 (Needs_Simple_Initialization (Etype (E))
2807 and then not Is_Internal (E)))
2808 then
2809 Has_Default_Initialization := True;
2810 Check_Restriction
2811 (No_Default_Initialization, Declaration_Node (E));
2812 end if;
2813
2814 -- Check that a Thread_Local_Storage variable does not have
2815 -- default initialization, and any explicit initialization must
2816 -- either be the null constant or a static constant.
2817
2818 if Has_Pragma_Thread_Local_Storage (E) then
2819 declare
2820 Decl : constant Node_Id := Declaration_Node (E);
2821 begin
2822 if Has_Default_Initialization
2823 or else
2824 (Has_Init_Expression (Decl)
2825 and then
2826 (No (Expression (Decl))
2827 or else not
2828 (Is_Static_Expression (Expression (Decl))
2829 or else
2830 Nkind (Expression (Decl)) = N_Null)))
2831 then
2832 Error_Msg_NE
2833 ("Thread_Local_Storage variable& is "
2834 & "improperly initialized", Decl, E);
2835 Error_Msg_NE
2836 ("\only allowed initialization is explicit "
2837 & "NULL or static expression", Decl, E);
2838 end if;
2839 end;
2840 end if;
2841
2842 -- For imported objects, set Is_Public unless there is also an
2843 -- address clause, which means that there is no external symbol
2844 -- needed for the Import (Is_Public may still be set for other
2845 -- unrelated reasons). Note that we delayed this processing
2846 -- till freeze time so that we can be sure not to set the flag
2847 -- if there is an address clause. If there is such a clause,
2848 -- then the only purpose of the Import pragma is to suppress
2849 -- implicit initialization.
2850
2851 if Is_Imported (E)
2852 and then No (Address_Clause (E))
2853 then
2854 Set_Is_Public (E);
2855 end if;
2856
2857 -- For convention C objects of an enumeration type, warn if
2858 -- the size is not integer size and no explicit size given.
2859 -- Skip warning for Boolean, and Character, assume programmer
2860 -- expects 8-bit sizes for these cases.
2861
2862 if (Convention (E) = Convention_C
2863 or else
2864 Convention (E) = Convention_CPP)
2865 and then Is_Enumeration_Type (Etype (E))
2866 and then not Is_Character_Type (Etype (E))
2867 and then not Is_Boolean_Type (Etype (E))
2868 and then Esize (Etype (E)) < Standard_Integer_Size
2869 and then not Has_Size_Clause (E)
2870 then
2871 Error_Msg_Uint_1 := UI_From_Int (Standard_Integer_Size);
2872 Error_Msg_N
2873 ("?convention C enumeration object has size less than ^",
2874 E);
2875 Error_Msg_N ("\?use explicit size clause to set size", E);
2876 end if;
2877 end if;
2878
2879 -- Check that a constant which has a pragma Volatile[_Components]
2880 -- or Atomic[_Components] also has a pragma Import (RM C.6(13)).
2881
2882 -- Note: Atomic[_Components] also sets Volatile[_Components]
2883
2884 if Ekind (E) = E_Constant
2885 and then (Has_Volatile_Components (E) or else Is_Volatile (E))
2886 and then not Is_Imported (E)
2887 then
2888 -- Make sure we actually have a pragma, and have not merely
2889 -- inherited the indication from elsewhere (e.g. an address
2890 -- clause, which is not good enough in RM terms!)
2891
2892 if Has_Rep_Pragma (E, Name_Atomic)
2893 or else
2894 Has_Rep_Pragma (E, Name_Atomic_Components)
2895 then
2896 Error_Msg_N
2897 ("stand alone atomic constant must be " &
2898 "imported (RM C.6(13))", E);
2899
2900 elsif Has_Rep_Pragma (E, Name_Volatile)
2901 or else
2902 Has_Rep_Pragma (E, Name_Volatile_Components)
2903 then
2904 Error_Msg_N
2905 ("stand alone volatile constant must be " &
2906 "imported (RM C.6(13))", E);
2907 end if;
2908 end if;
2909
2910 -- Static objects require special handling
2911
2912 if (Ekind (E) = E_Constant or else Ekind (E) = E_Variable)
2913 and then Is_Statically_Allocated (E)
2914 then
2915 Freeze_Static_Object (E);
2916 end if;
2917
2918 -- Remaining step is to layout objects
2919
2920 if Ekind (E) = E_Variable
2921 or else
2922 Ekind (E) = E_Constant
2923 or else
2924 Ekind (E) = E_Loop_Parameter
2925 or else
2926 Is_Formal (E)
2927 then
2928 Layout_Object (E);
2929 end if;
2930 end if;
2931
2932 -- Case of a type or subtype being frozen
2933
2934 else
2935 -- We used to check here that a full type must have preelaborable
2936 -- initialization if it completes a private type specified with
2937 -- pragma Preelaborable_Intialization, but that missed cases where
2938 -- the types occur within a generic package, since the freezing
2939 -- that occurs within a containing scope generally skips traversal
2940 -- of a generic unit's declarations (those will be frozen within
2941 -- instances). This check was moved to Analyze_Package_Specification.
2942
2943 -- The type may be defined in a generic unit. This can occur when
2944 -- freezing a generic function that returns the type (which is
2945 -- defined in a parent unit). It is clearly meaningless to freeze
2946 -- this type. However, if it is a subtype, its size may be determi-
2947 -- nable and used in subsequent checks, so might as well try to
2948 -- compute it.
2949
2950 if Present (Scope (E))
2951 and then Is_Generic_Unit (Scope (E))
2952 then
2953 Check_Compile_Time_Size (E);
2954 return No_List;
2955 end if;
2956
2957 -- Deal with special cases of freezing for subtype
2958
2959 if E /= Base_Type (E) then
2960
2961 -- Before we do anything else, a specialized test for the case of
2962 -- a size given for an array where the array needs to be packed,
2963 -- but was not so the size cannot be honored. This would of course
2964 -- be caught by the backend, and indeed we don't catch all cases.
2965 -- The point is that we can give a better error message in those
2966 -- cases that we do catch with the circuitry here. Also if pragma
2967 -- Implicit_Packing is set, this is where the packing occurs.
2968
2969 -- The reason we do this so early is that the processing in the
2970 -- automatic packing case affects the layout of the base type, so
2971 -- it must be done before we freeze the base type.
2972
2973 if Is_Array_Type (E) then
2974 declare
2975 Lo, Hi : Node_Id;
2976 Ctyp : constant Entity_Id := Component_Type (E);
2977
2978 begin
2979 -- Check enabling conditions. These are straightforward
2980 -- except for the test for a limited composite type. This
2981 -- eliminates the rare case of a array of limited components
2982 -- where there are issues of whether or not we can go ahead
2983 -- and pack the array (since we can't freely pack and unpack
2984 -- arrays if they are limited).
2985
2986 -- Note that we check the root type explicitly because the
2987 -- whole point is we are doing this test before we have had
2988 -- a chance to freeze the base type (and it is that freeze
2989 -- action that causes stuff to be inherited).
2990
2991 if Present (Size_Clause (E))
2992 and then Known_Static_Esize (E)
2993 and then not Is_Packed (E)
2994 and then not Has_Pragma_Pack (E)
2995 and then Number_Dimensions (E) = 1
2996 and then not Has_Component_Size_Clause (E)
2997 and then Known_Static_Esize (Ctyp)
2998 and then not Is_Limited_Composite (E)
2999 and then not Is_Packed (Root_Type (E))
3000 and then not Has_Component_Size_Clause (Root_Type (E))
3001 and then not CodePeer_Mode
3002 then
3003 Get_Index_Bounds (First_Index (E), Lo, Hi);
3004
3005 if Compile_Time_Known_Value (Lo)
3006 and then Compile_Time_Known_Value (Hi)
3007 and then Known_Static_RM_Size (Ctyp)
3008 and then RM_Size (Ctyp) < 64
3009 then
3010 declare
3011 Lov : constant Uint := Expr_Value (Lo);
3012 Hiv : constant Uint := Expr_Value (Hi);
3013 Len : constant Uint := UI_Max
3014 (Uint_0,
3015 Hiv - Lov + 1);
3016 Rsiz : constant Uint := RM_Size (Ctyp);
3017 SZ : constant Node_Id := Size_Clause (E);
3018 Btyp : constant Entity_Id := Base_Type (E);
3019
3020 -- What we are looking for here is the situation where
3021 -- the RM_Size given would be exactly right if there
3022 -- was a pragma Pack (resulting in the component size
3023 -- being the same as the RM_Size). Furthermore, the
3024 -- component type size must be an odd size (not a
3025 -- multiple of storage unit). If the component RM size
3026 -- is an exact number of storage units that is a power
3027 -- of two, the array is not packed and has a standard
3028 -- representation.
3029
3030 begin
3031 if RM_Size (E) = Len * Rsiz
3032 and then Rsiz mod System_Storage_Unit /= 0
3033 then
3034 -- For implicit packing mode, just set the
3035 -- component size silently.
3036
3037 if Implicit_Packing then
3038 Set_Component_Size (Btyp, Rsiz);
3039 Set_Is_Bit_Packed_Array (Btyp);
3040 Set_Is_Packed (Btyp);
3041 Set_Has_Non_Standard_Rep (Btyp);
3042
3043 -- Otherwise give an error message
3044
3045 else
3046 Error_Msg_NE
3047 ("size given for& too small", SZ, E);
3048 Error_Msg_N -- CODEFIX
3049 ("\use explicit pragma Pack "
3050 & "or use pragma Implicit_Packing", SZ);
3051 end if;
3052
3053 elsif RM_Size (E) = Len * Rsiz
3054 and then Implicit_Packing
3055 and then
3056 (Rsiz / System_Storage_Unit = 1
3057 or else Rsiz / System_Storage_Unit = 2
3058 or else Rsiz / System_Storage_Unit = 4)
3059 then
3060
3061 -- Not a packed array, but indicate the desired
3062 -- component size, for the back-end.
3063
3064 Set_Component_Size (Btyp, Rsiz);
3065 end if;
3066 end;
3067 end if;
3068 end if;
3069 end;
3070 end if;
3071
3072 -- If ancestor subtype present, freeze that first. Note that this
3073 -- will also get the base type frozen.
3074
3075 Atype := Ancestor_Subtype (E);
3076
3077 if Present (Atype) then
3078 Freeze_And_Append (Atype, Loc, Result);
3079
3080 -- Otherwise freeze the base type of the entity before freezing
3081 -- the entity itself (RM 13.14(15)).
3082
3083 elsif E /= Base_Type (E) then
3084 Freeze_And_Append (Base_Type (E), Loc, Result);
3085 end if;
3086
3087 -- For a derived type, freeze its parent type first (RM 13.14(15))
3088
3089 elsif Is_Derived_Type (E) then
3090 Freeze_And_Append (Etype (E), Loc, Result);
3091 Freeze_And_Append (First_Subtype (Etype (E)), Loc, Result);
3092 end if;
3093
3094 -- For array type, freeze index types and component type first
3095 -- before freezing the array (RM 13.14(15)).
3096
3097 if Is_Array_Type (E) then
3098 declare
3099 FS : constant Entity_Id := First_Subtype (E);
3100 Ctyp : constant Entity_Id := Component_Type (E);
3101 Clause : Entity_Id;
3102
3103 Non_Standard_Enum : Boolean := False;
3104 -- Set true if any of the index types is an enumeration type
3105 -- with a non-standard representation.
3106
3107 begin
3108 Freeze_And_Append (Ctyp, Loc, Result);
3109
3110 Indx := First_Index (E);
3111 while Present (Indx) loop
3112 Freeze_And_Append (Etype (Indx), Loc, Result);
3113
3114 if Is_Enumeration_Type (Etype (Indx))
3115 and then Has_Non_Standard_Rep (Etype (Indx))
3116 then
3117 Non_Standard_Enum := True;
3118 end if;
3119
3120 Next_Index (Indx);
3121 end loop;
3122
3123 -- Processing that is done only for base types
3124
3125 if Ekind (E) = E_Array_Type then
3126
3127 -- Propagate flags for component type
3128
3129 if Is_Controlled (Component_Type (E))
3130 or else Has_Controlled_Component (Ctyp)
3131 then
3132 Set_Has_Controlled_Component (E);
3133 end if;
3134
3135 if Has_Unchecked_Union (Component_Type (E)) then
3136 Set_Has_Unchecked_Union (E);
3137 end if;
3138
3139 -- If packing was requested or if the component size was set
3140 -- explicitly, then see if bit packing is required. This
3141 -- processing is only done for base types, since all the
3142 -- representation aspects involved are type-related. This
3143 -- is not just an optimization, if we start processing the
3144 -- subtypes, they interfere with the settings on the base
3145 -- type (this is because Is_Packed has a slightly different
3146 -- meaning before and after freezing).
3147
3148 declare
3149 Csiz : Uint;
3150 Esiz : Uint;
3151
3152 begin
3153 if (Is_Packed (E) or else Has_Pragma_Pack (E))
3154 and then Known_Static_RM_Size (Ctyp)
3155 and then not Has_Component_Size_Clause (E)
3156 then
3157 Csiz := UI_Max (RM_Size (Ctyp), 1);
3158
3159 elsif Known_Component_Size (E) then
3160 Csiz := Component_Size (E);
3161
3162 elsif not Known_Static_Esize (Ctyp) then
3163 Csiz := Uint_0;
3164
3165 else
3166 Esiz := Esize (Ctyp);
3167
3168 -- We can set the component size if it is less than
3169 -- 16, rounding it up to the next storage unit size.
3170
3171 if Esiz <= 8 then
3172 Csiz := Uint_8;
3173 elsif Esiz <= 16 then
3174 Csiz := Uint_16;
3175 else
3176 Csiz := Uint_0;
3177 end if;
3178
3179 -- Set component size up to match alignment if it
3180 -- would otherwise be less than the alignment. This
3181 -- deals with cases of types whose alignment exceeds
3182 -- their size (padded types).
3183
3184 if Csiz /= 0 then
3185 declare
3186 A : constant Uint := Alignment_In_Bits (Ctyp);
3187 begin
3188 if Csiz < A then
3189 Csiz := A;
3190 end if;
3191 end;
3192 end if;
3193 end if;
3194
3195 -- Case of component size that may result in packing
3196
3197 if 1 <= Csiz and then Csiz <= 64 then
3198 declare
3199 Ent : constant Entity_Id :=
3200 First_Subtype (E);
3201 Pack_Pragma : constant Node_Id :=
3202 Get_Rep_Pragma (Ent, Name_Pack);
3203 Comp_Size_C : constant Node_Id :=
3204 Get_Attribute_Definition_Clause
3205 (Ent, Attribute_Component_Size);
3206 begin
3207 -- Warn if we have pack and component size so that
3208 -- the pack is ignored.
3209
3210 -- Note: here we must check for the presence of a
3211 -- component size before checking for a Pack pragma
3212 -- to deal with the case where the array type is a
3213 -- derived type whose parent is currently private.
3214
3215 if Present (Comp_Size_C)
3216 and then Has_Pragma_Pack (Ent)
3217 and then Warn_On_Redundant_Constructs
3218 then
3219 Error_Msg_Sloc := Sloc (Comp_Size_C);
3220 Error_Msg_NE
3221 ("?pragma Pack for& ignored!",
3222 Pack_Pragma, Ent);
3223 Error_Msg_N
3224 ("\?explicit component size given#!",
3225 Pack_Pragma);
3226 Set_Is_Packed (Base_Type (Ent), False);
3227 Set_Is_Bit_Packed_Array (Base_Type (Ent), False);
3228 end if;
3229
3230 -- Set component size if not already set by a
3231 -- component size clause.
3232
3233 if not Present (Comp_Size_C) then
3234 Set_Component_Size (E, Csiz);
3235 end if;
3236
3237 -- Check for base type of 8, 16, 32 bits, where an
3238 -- unsigned subtype has a length one less than the
3239 -- base type (e.g. Natural subtype of Integer).
3240
3241 -- In such cases, if a component size was not set
3242 -- explicitly, then generate a warning.
3243
3244 if Has_Pragma_Pack (E)
3245 and then not Present (Comp_Size_C)
3246 and then
3247 (Csiz = 7 or else Csiz = 15 or else Csiz = 31)
3248 and then Esize (Base_Type (Ctyp)) = Csiz + 1
3249 then
3250 Error_Msg_Uint_1 := Csiz;
3251
3252 if Present (Pack_Pragma) then
3253 Error_Msg_N
3254 ("?pragma Pack causes component size "
3255 & "to be ^!", Pack_Pragma);
3256 Error_Msg_N
3257 ("\?use Component_Size to set "
3258 & "desired value!", Pack_Pragma);
3259 end if;
3260 end if;
3261
3262 -- Actual packing is not needed for 8, 16, 32, 64.
3263 -- Also not needed for 24 if alignment is 1.
3264
3265 if Csiz = 8
3266 or else Csiz = 16
3267 or else Csiz = 32
3268 or else Csiz = 64
3269 or else (Csiz = 24 and then Alignment (Ctyp) = 1)
3270 then
3271 -- Here the array was requested to be packed,
3272 -- but the packing request had no effect, so
3273 -- Is_Packed is reset.
3274
3275 -- Note: semantically this means that we lose
3276 -- track of the fact that a derived type
3277 -- inherited a pragma Pack that was non-
3278 -- effective, but that seems fine.
3279
3280 -- We regard a Pack pragma as a request to set
3281 -- a representation characteristic, and this
3282 -- request may be ignored.
3283
3284 Set_Is_Packed (Base_Type (E), False);
3285 Set_Is_Bit_Packed_Array (Base_Type (E), False);
3286
3287 if Known_Static_Esize (Component_Type (E))
3288 and then Esize (Component_Type (E)) = Csiz
3289 then
3290 Set_Has_Non_Standard_Rep
3291 (Base_Type (E), False);
3292 end if;
3293
3294 -- In all other cases, packing is indeed needed
3295
3296 else
3297 Set_Has_Non_Standard_Rep (Base_Type (E), True);
3298 Set_Is_Bit_Packed_Array (Base_Type (E), True);
3299 Set_Is_Packed (Base_Type (E), True);
3300 end if;
3301 end;
3302 end if;
3303 end;
3304
3305 -- Check for Atomic_Components or Aliased with unsuitable
3306 -- packing or explicit component size clause given.
3307
3308 if (Has_Atomic_Components (E)
3309 or else Has_Aliased_Components (E))
3310 and then (Has_Component_Size_Clause (E)
3311 or else Is_Packed (E))
3312 then
3313 Alias_Atomic_Check : declare
3314
3315 procedure Complain_CS (T : String);
3316 -- Outputs error messages for incorrect CS clause or
3317 -- pragma Pack for aliased or atomic components (T is
3318 -- "aliased" or "atomic");
3319
3320 -----------------
3321 -- Complain_CS --
3322 -----------------
3323
3324 procedure Complain_CS (T : String) is
3325 begin
3326 if Has_Component_Size_Clause (E) then
3327 Clause :=
3328 Get_Attribute_Definition_Clause
3329 (FS, Attribute_Component_Size);
3330
3331 if Known_Static_Esize (Ctyp) then
3332 Error_Msg_N
3333 ("incorrect component size for "
3334 & T & " components", Clause);
3335 Error_Msg_Uint_1 := Esize (Ctyp);
3336 Error_Msg_N
3337 ("\only allowed value is^", Clause);
3338
3339 else
3340 Error_Msg_N
3341 ("component size cannot be given for "
3342 & T & " components", Clause);
3343 end if;
3344
3345 else
3346 Error_Msg_N
3347 ("cannot pack " & T & " components",
3348 Get_Rep_Pragma (FS, Name_Pack));
3349 end if;
3350
3351 return;
3352 end Complain_CS;
3353
3354 -- Start of processing for Alias_Atomic_Check
3355
3356 begin
3357 -- Case where component size has no effect
3358
3359 if Known_Static_Esize (Ctyp)
3360 and then Known_Static_RM_Size (Ctyp)
3361 and then Esize (Ctyp) = RM_Size (Ctyp)
3362 and then Esize (Ctyp) mod 8 = 0
3363 then
3364 null;
3365
3366 elsif Has_Aliased_Components (E)
3367 or else Is_Aliased (Ctyp)
3368 then
3369 Complain_CS ("aliased");
3370
3371 elsif Has_Atomic_Components (E)
3372 or else Is_Atomic (Ctyp)
3373 then
3374 Complain_CS ("atomic");
3375 end if;
3376 end Alias_Atomic_Check;
3377 end if;
3378
3379 -- Warn for case of atomic type
3380
3381 Clause := Get_Rep_Pragma (FS, Name_Atomic);
3382
3383 if Present (Clause)
3384 and then not Addressable (Component_Size (FS))
3385 then
3386 Error_Msg_NE
3387 ("non-atomic components of type& may not be "
3388 & "accessible by separate tasks?", Clause, E);
3389
3390 if Has_Component_Size_Clause (E) then
3391 Error_Msg_Sloc :=
3392 Sloc
3393 (Get_Attribute_Definition_Clause
3394 (FS, Attribute_Component_Size));
3395 Error_Msg_N
3396 ("\because of component size clause#?",
3397 Clause);
3398
3399 elsif Has_Pragma_Pack (E) then
3400 Error_Msg_Sloc :=
3401 Sloc (Get_Rep_Pragma (FS, Name_Pack));
3402 Error_Msg_N
3403 ("\because of pragma Pack#?", Clause);
3404 end if;
3405 end if;
3406
3407 -- Processing that is done only for subtypes
3408
3409 else
3410 -- Acquire alignment from base type
3411
3412 if Unknown_Alignment (E) then
3413 Set_Alignment (E, Alignment (Base_Type (E)));
3414 Adjust_Esize_Alignment (E);
3415 end if;
3416 end if;
3417
3418 -- For bit-packed arrays, check the size
3419
3420 if Is_Bit_Packed_Array (E) and then Known_RM_Size (E) then
3421 declare
3422 SizC : constant Node_Id := Size_Clause (E);
3423
3424 Discard : Boolean;
3425 pragma Warnings (Off, Discard);
3426
3427 begin
3428 -- It is not clear if it is possible to have no size
3429 -- clause at this stage, but it is not worth worrying
3430 -- about. Post error on the entity name in the size
3431 -- clause if present, else on the type entity itself.
3432
3433 if Present (SizC) then
3434 Check_Size (Name (SizC), E, RM_Size (E), Discard);
3435 else
3436 Check_Size (E, E, RM_Size (E), Discard);
3437 end if;
3438 end;
3439 end if;
3440
3441 -- If any of the index types was an enumeration type with
3442 -- a non-standard rep clause, then we indicate that the
3443 -- array type is always packed (even if it is not bit packed).
3444
3445 if Non_Standard_Enum then
3446 Set_Has_Non_Standard_Rep (Base_Type (E));
3447 Set_Is_Packed (Base_Type (E));
3448 end if;
3449
3450 Set_Component_Alignment_If_Not_Set (E);
3451
3452 -- If the array is packed, we must create the packed array
3453 -- type to be used to actually implement the type. This is
3454 -- only needed for real array types (not for string literal
3455 -- types, since they are present only for the front end).
3456
3457 if Is_Packed (E)
3458 and then Ekind (E) /= E_String_Literal_Subtype
3459 then
3460 Create_Packed_Array_Type (E);
3461 Freeze_And_Append (Packed_Array_Type (E), Loc, Result);
3462
3463 -- Size information of packed array type is copied to the
3464 -- array type, since this is really the representation. But
3465 -- do not override explicit existing size values. If the
3466 -- ancestor subtype is constrained the packed_array_type
3467 -- will be inherited from it, but the size may have been
3468 -- provided already, and must not be overridden either.
3469
3470 if not Has_Size_Clause (E)
3471 and then
3472 (No (Ancestor_Subtype (E))
3473 or else not Has_Size_Clause (Ancestor_Subtype (E)))
3474 then
3475 Set_Esize (E, Esize (Packed_Array_Type (E)));
3476 Set_RM_Size (E, RM_Size (Packed_Array_Type (E)));
3477 end if;
3478
3479 if not Has_Alignment_Clause (E) then
3480 Set_Alignment (E, Alignment (Packed_Array_Type (E)));
3481 end if;
3482 end if;
3483
3484 -- For non-packed arrays set the alignment of the array to the
3485 -- alignment of the component type if it is unknown. Skip this
3486 -- in atomic case (atomic arrays may need larger alignments).
3487
3488 if not Is_Packed (E)
3489 and then Unknown_Alignment (E)
3490 and then Known_Alignment (Ctyp)
3491 and then Known_Static_Component_Size (E)
3492 and then Known_Static_Esize (Ctyp)
3493 and then Esize (Ctyp) = Component_Size (E)
3494 and then not Is_Atomic (E)
3495 then
3496 Set_Alignment (E, Alignment (Component_Type (E)));
3497 end if;
3498 end;
3499
3500 -- For a class-wide type, the corresponding specific type is
3501 -- frozen as well (RM 13.14(15))
3502
3503 elsif Is_Class_Wide_Type (E) then
3504 Freeze_And_Append (Root_Type (E), Loc, Result);
3505
3506 -- If the base type of the class-wide type is still incomplete,
3507 -- the class-wide remains unfrozen as well. This is legal when
3508 -- E is the formal of a primitive operation of some other type
3509 -- which is being frozen.
3510
3511 if not Is_Frozen (Root_Type (E)) then
3512 Set_Is_Frozen (E, False);
3513 return Result;
3514 end if;
3515
3516 -- If the Class_Wide_Type is an Itype (when type is the anonymous
3517 -- parent of a derived type) and it is a library-level entity,
3518 -- generate an itype reference for it. Otherwise, its first
3519 -- explicit reference may be in an inner scope, which will be
3520 -- rejected by the back-end.
3521
3522 if Is_Itype (E)
3523 and then Is_Compilation_Unit (Scope (E))
3524 then
3525 declare
3526 Ref : constant Node_Id := Make_Itype_Reference (Loc);
3527
3528 begin
3529 Set_Itype (Ref, E);
3530 if No (Result) then
3531 Result := New_List (Ref);
3532 else
3533 Append (Ref, Result);
3534 end if;
3535 end;
3536 end if;
3537
3538 -- The equivalent type associated with a class-wide subtype needs
3539 -- to be frozen to ensure that its layout is done.
3540
3541 if Ekind (E) = E_Class_Wide_Subtype
3542 and then Present (Equivalent_Type (E))
3543 then
3544 Freeze_And_Append (Equivalent_Type (E), Loc, Result);
3545 end if;
3546
3547 -- For a record (sub)type, freeze all the component types (RM
3548 -- 13.14(15). We test for E_Record_(sub)Type here, rather than using
3549 -- Is_Record_Type, because we don't want to attempt the freeze for
3550 -- the case of a private type with record extension (we will do that
3551 -- later when the full type is frozen).
3552
3553 elsif Ekind (E) = E_Record_Type
3554 or else Ekind (E) = E_Record_Subtype
3555 then
3556 Freeze_Record_Type (E);
3557
3558 -- For a concurrent type, freeze corresponding record type. This
3559 -- does not correspond to any specific rule in the RM, but the
3560 -- record type is essentially part of the concurrent type.
3561 -- Freeze as well all local entities. This includes record types
3562 -- created for entry parameter blocks, and whatever local entities
3563 -- may appear in the private part.
3564
3565 elsif Is_Concurrent_Type (E) then
3566 if Present (Corresponding_Record_Type (E)) then
3567 Freeze_And_Append
3568 (Corresponding_Record_Type (E), Loc, Result);
3569 end if;
3570
3571 Comp := First_Entity (E);
3572 while Present (Comp) loop
3573 if Is_Type (Comp) then
3574 Freeze_And_Append (Comp, Loc, Result);
3575
3576 elsif (Ekind (Comp)) /= E_Function then
3577 if Is_Itype (Etype (Comp))
3578 and then Underlying_Type (Scope (Etype (Comp))) = E
3579 then
3580 Undelay_Type (Etype (Comp));
3581 end if;
3582
3583 Freeze_And_Append (Etype (Comp), Loc, Result);
3584 end if;
3585
3586 Next_Entity (Comp);
3587 end loop;
3588
3589 -- Private types are required to point to the same freeze node as
3590 -- their corresponding full views. The freeze node itself has to
3591 -- point to the partial view of the entity (because from the partial
3592 -- view, we can retrieve the full view, but not the reverse).
3593 -- However, in order to freeze correctly, we need to freeze the full
3594 -- view. If we are freezing at the end of a scope (or within the
3595 -- scope of the private type), the partial and full views will have
3596 -- been swapped, the full view appears first in the entity chain and
3597 -- the swapping mechanism ensures that the pointers are properly set
3598 -- (on scope exit).
3599
3600 -- If we encounter the partial view before the full view (e.g. when
3601 -- freezing from another scope), we freeze the full view, and then
3602 -- set the pointers appropriately since we cannot rely on swapping to
3603 -- fix things up (subtypes in an outer scope might not get swapped).
3604
3605 elsif Is_Incomplete_Or_Private_Type (E)
3606 and then not Is_Generic_Type (E)
3607 then
3608 -- The construction of the dispatch table associated with library
3609 -- level tagged types forces freezing of all the primitives of the
3610 -- type, which may cause premature freezing of the partial view.
3611 -- For example:
3612
3613 -- package Pkg is
3614 -- type T is tagged private;
3615 -- type DT is new T with private;
3616 -- procedure Prim (X : in out T; Y : in out DT'class);
3617 -- private
3618 -- type T is tagged null record;
3619 -- Obj : T;
3620 -- type DT is new T with null record;
3621 -- end;
3622
3623 -- In this case the type will be frozen later by the usual
3624 -- mechanism: an object declaration, an instantiation, or the
3625 -- end of a declarative part.
3626
3627 if Is_Library_Level_Tagged_Type (E)
3628 and then not Present (Full_View (E))
3629 then
3630 Set_Is_Frozen (E, False);
3631 return Result;
3632
3633 -- Case of full view present
3634
3635 elsif Present (Full_View (E)) then
3636
3637 -- If full view has already been frozen, then no further
3638 -- processing is required
3639
3640 if Is_Frozen (Full_View (E)) then
3641
3642 Set_Has_Delayed_Freeze (E, False);
3643 Set_Freeze_Node (E, Empty);
3644 Check_Debug_Info_Needed (E);
3645
3646 -- Otherwise freeze full view and patch the pointers so that
3647 -- the freeze node will elaborate both views in the back-end.
3648
3649 else
3650 declare
3651 Full : constant Entity_Id := Full_View (E);
3652
3653 begin
3654 if Is_Private_Type (Full)
3655 and then Present (Underlying_Full_View (Full))
3656 then
3657 Freeze_And_Append
3658 (Underlying_Full_View (Full), Loc, Result);
3659 end if;
3660
3661 Freeze_And_Append (Full, Loc, Result);
3662
3663 if Has_Delayed_Freeze (E) then
3664 F_Node := Freeze_Node (Full);
3665
3666 if Present (F_Node) then
3667 Set_Freeze_Node (E, F_Node);
3668 Set_Entity (F_Node, E);
3669
3670 else
3671 -- {Incomplete,Private}_Subtypes with Full_Views
3672 -- constrained by discriminants.
3673
3674 Set_Has_Delayed_Freeze (E, False);
3675 Set_Freeze_Node (E, Empty);
3676 end if;
3677 end if;
3678 end;
3679
3680 Check_Debug_Info_Needed (E);
3681 end if;
3682
3683 -- AI-117 requires that the convention of a partial view be the
3684 -- same as the convention of the full view. Note that this is a
3685 -- recognized breach of privacy, but it's essential for logical
3686 -- consistency of representation, and the lack of a rule in
3687 -- RM95 was an oversight.
3688
3689 Set_Convention (E, Convention (Full_View (E)));
3690
3691 Set_Size_Known_At_Compile_Time (E,
3692 Size_Known_At_Compile_Time (Full_View (E)));
3693
3694 -- Size information is copied from the full view to the
3695 -- incomplete or private view for consistency.
3696
3697 -- We skip this is the full view is not a type. This is very
3698 -- strange of course, and can only happen as a result of
3699 -- certain illegalities, such as a premature attempt to derive
3700 -- from an incomplete type.
3701
3702 if Is_Type (Full_View (E)) then
3703 Set_Size_Info (E, Full_View (E));
3704 Set_RM_Size (E, RM_Size (Full_View (E)));
3705 end if;
3706
3707 return Result;
3708
3709 -- Case of no full view present. If entity is derived or subtype,
3710 -- it is safe to freeze, correctness depends on the frozen status
3711 -- of parent. Otherwise it is either premature usage, or a Taft
3712 -- amendment type, so diagnosis is at the point of use and the
3713 -- type might be frozen later.
3714
3715 elsif E /= Base_Type (E)
3716 or else Is_Derived_Type (E)
3717 then
3718 null;
3719
3720 else
3721 Set_Is_Frozen (E, False);
3722 return No_List;
3723 end if;
3724
3725 -- For access subprogram, freeze types of all formals, the return
3726 -- type was already frozen, since it is the Etype of the function.
3727 -- Formal types can be tagged Taft amendment types, but otherwise
3728 -- they cannot be incomplete.
3729
3730 elsif Ekind (E) = E_Subprogram_Type then
3731 Formal := First_Formal (E);
3732 while Present (Formal) loop
3733 if Ekind (Etype (Formal)) = E_Incomplete_Type
3734 and then No (Full_View (Etype (Formal)))
3735 and then not Is_Value_Type (Etype (Formal))
3736 then
3737 if Is_Tagged_Type (Etype (Formal)) then
3738 null;
3739
3740 -- AI05-151: Incomplete types are allowed in access to
3741 -- subprogram specifications.
3742
3743 elsif Ada_Version < Ada_2012 then
3744 Error_Msg_NE
3745 ("invalid use of incomplete type&", E, Etype (Formal));
3746 end if;
3747 end if;
3748
3749 Freeze_And_Append (Etype (Formal), Loc, Result);
3750 Next_Formal (Formal);
3751 end loop;
3752
3753 Freeze_Subprogram (E);
3754
3755 -- For access to a protected subprogram, freeze the equivalent type
3756 -- (however this is not set if we are not generating code or if this
3757 -- is an anonymous type used just for resolution).
3758
3759 elsif Is_Access_Protected_Subprogram_Type (E) then
3760 if Present (Equivalent_Type (E)) then
3761 Freeze_And_Append (Equivalent_Type (E), Loc, Result);
3762 end if;
3763 end if;
3764
3765 -- Generic types are never seen by the back-end, and are also not
3766 -- processed by the expander (since the expander is turned off for
3767 -- generic processing), so we never need freeze nodes for them.
3768
3769 if Is_Generic_Type (E) then
3770 return Result;
3771 end if;
3772
3773 -- Some special processing for non-generic types to complete
3774 -- representation details not known till the freeze point.
3775
3776 if Is_Fixed_Point_Type (E) then
3777 Freeze_Fixed_Point_Type (E);
3778
3779 -- Some error checks required for ordinary fixed-point type. Defer
3780 -- these till the freeze-point since we need the small and range
3781 -- values. We only do these checks for base types
3782
3783 if Is_Ordinary_Fixed_Point_Type (E)
3784 and then E = Base_Type (E)
3785 then
3786 if Small_Value (E) < Ureal_2_M_80 then
3787 Error_Msg_Name_1 := Name_Small;
3788 Error_Msg_N
3789 ("`&''%` too small, minimum allowed is 2.0'*'*(-80)", E);
3790
3791 elsif Small_Value (E) > Ureal_2_80 then
3792 Error_Msg_Name_1 := Name_Small;
3793 Error_Msg_N
3794 ("`&''%` too large, maximum allowed is 2.0'*'*80", E);
3795 end if;
3796
3797 if Expr_Value_R (Type_Low_Bound (E)) < Ureal_M_10_36 then
3798 Error_Msg_Name_1 := Name_First;
3799 Error_Msg_N
3800 ("`&''%` too small, minimum allowed is -10.0'*'*36", E);
3801 end if;
3802
3803 if Expr_Value_R (Type_High_Bound (E)) > Ureal_10_36 then
3804 Error_Msg_Name_1 := Name_Last;
3805 Error_Msg_N
3806 ("`&''%` too large, maximum allowed is 10.0'*'*36", E);
3807 end if;
3808 end if;
3809
3810 elsif Is_Enumeration_Type (E) then
3811 Freeze_Enumeration_Type (E);
3812
3813 elsif Is_Integer_Type (E) then
3814 Adjust_Esize_For_Alignment (E);
3815
3816 if Is_Modular_Integer_Type (E)
3817 and then Warn_On_Suspicious_Modulus_Value
3818 then
3819 Check_Suspicious_Modulus (E);
3820 end if;
3821
3822 elsif Is_Access_Type (E) then
3823
3824 -- Check restriction for standard storage pool
3825
3826 if No (Associated_Storage_Pool (E)) then
3827 Check_Restriction (No_Standard_Storage_Pools, E);
3828 end if;
3829
3830 -- Deal with error message for pure access type. This is not an
3831 -- error in Ada 2005 if there is no pool (see AI-366).
3832
3833 if Is_Pure_Unit_Access_Type (E)
3834 and then (Ada_Version < Ada_2005
3835 or else not No_Pool_Assigned (E))
3836 then
3837 Error_Msg_N ("named access type not allowed in pure unit", E);
3838
3839 if Ada_Version >= Ada_2005 then
3840 Error_Msg_N
3841 ("\would be legal if Storage_Size of 0 given?", E);
3842
3843 elsif No_Pool_Assigned (E) then
3844 Error_Msg_N
3845 ("\would be legal in Ada 2005?", E);
3846
3847 else
3848 Error_Msg_N
3849 ("\would be legal in Ada 2005 if "
3850 & "Storage_Size of 0 given?", E);
3851 end if;
3852 end if;
3853 end if;
3854
3855 -- Case of composite types
3856
3857 if Is_Composite_Type (E) then
3858
3859 -- AI-117 requires that all new primitives of a tagged type must
3860 -- inherit the convention of the full view of the type. Inherited
3861 -- and overriding operations are defined to inherit the convention
3862 -- of their parent or overridden subprogram (also specified in
3863 -- AI-117), which will have occurred earlier (in Derive_Subprogram
3864 -- and New_Overloaded_Entity). Here we set the convention of
3865 -- primitives that are still convention Ada, which will ensure
3866 -- that any new primitives inherit the type's convention. Class-
3867 -- wide types can have a foreign convention inherited from their
3868 -- specific type, but are excluded from this since they don't have
3869 -- any associated primitives.
3870
3871 if Is_Tagged_Type (E)
3872 and then not Is_Class_Wide_Type (E)
3873 and then Convention (E) /= Convention_Ada
3874 then
3875 declare
3876 Prim_List : constant Elist_Id := Primitive_Operations (E);
3877 Prim : Elmt_Id;
3878
3879 begin
3880 Prim := First_Elmt (Prim_List);
3881 while Present (Prim) loop
3882 if Convention (Node (Prim)) = Convention_Ada then
3883 Set_Convention (Node (Prim), Convention (E));
3884 end if;
3885
3886 Next_Elmt (Prim);
3887 end loop;
3888 end;
3889 end if;
3890 end if;
3891
3892 -- Now that all types from which E may depend are frozen, see if the
3893 -- size is known at compile time, if it must be unsigned, or if
3894 -- strict alignment is required
3895
3896 Check_Compile_Time_Size (E);
3897 Check_Unsigned_Type (E);
3898
3899 if Base_Type (E) = E then
3900 Check_Strict_Alignment (E);
3901 end if;
3902
3903 -- Do not allow a size clause for a type which does not have a size
3904 -- that is known at compile time
3905
3906 if Has_Size_Clause (E)
3907 and then not Size_Known_At_Compile_Time (E)
3908 then
3909 -- Suppress this message if errors posted on E, even if we are
3910 -- in all errors mode, since this is often a junk message
3911
3912 if not Error_Posted (E) then
3913 Error_Msg_N
3914 ("size clause not allowed for variable length type",
3915 Size_Clause (E));
3916 end if;
3917 end if;
3918
3919 -- Remaining process is to set/verify the representation information,
3920 -- in particular the size and alignment values. This processing is
3921 -- not required for generic types, since generic types do not play
3922 -- any part in code generation, and so the size and alignment values
3923 -- for such types are irrelevant.
3924
3925 if Is_Generic_Type (E) then
3926 return Result;
3927
3928 -- Otherwise we call the layout procedure
3929
3930 else
3931 Layout_Type (E);
3932 end if;
3933
3934 -- End of freeze processing for type entities
3935 end if;
3936
3937 -- Here is where we logically freeze the current entity. If it has a
3938 -- freeze node, then this is the point at which the freeze node is
3939 -- linked into the result list.
3940
3941 if Has_Delayed_Freeze (E) then
3942
3943 -- If a freeze node is already allocated, use it, otherwise allocate
3944 -- a new one. The preallocation happens in the case of anonymous base
3945 -- types, where we preallocate so that we can set First_Subtype_Link.
3946 -- Note that we reset the Sloc to the current freeze location.
3947
3948 if Present (Freeze_Node (E)) then
3949 F_Node := Freeze_Node (E);
3950 Set_Sloc (F_Node, Loc);
3951
3952 else
3953 F_Node := New_Node (N_Freeze_Entity, Loc);
3954 Set_Freeze_Node (E, F_Node);
3955 Set_Access_Types_To_Process (F_Node, No_Elist);
3956 Set_TSS_Elist (F_Node, No_Elist);
3957 Set_Actions (F_Node, No_List);
3958 end if;
3959
3960 Set_Entity (F_Node, E);
3961
3962 if Result = No_List then
3963 Result := New_List (F_Node);
3964 else
3965 Append (F_Node, Result);
3966 end if;
3967
3968 -- A final pass over record types with discriminants. If the type
3969 -- has an incomplete declaration, there may be constrained access
3970 -- subtypes declared elsewhere, which do not depend on the discrimi-
3971 -- nants of the type, and which are used as component types (i.e.
3972 -- the full view is a recursive type). The designated types of these
3973 -- subtypes can only be elaborated after the type itself, and they
3974 -- need an itype reference.
3975
3976 if Ekind (E) = E_Record_Type
3977 and then Has_Discriminants (E)
3978 then
3979 declare
3980 Comp : Entity_Id;
3981 IR : Node_Id;
3982 Typ : Entity_Id;
3983
3984 begin
3985 Comp := First_Component (E);
3986 while Present (Comp) loop
3987 Typ := Etype (Comp);
3988
3989 if Ekind (Comp) = E_Component
3990 and then Is_Access_Type (Typ)
3991 and then Scope (Typ) /= E
3992 and then Base_Type (Designated_Type (Typ)) = E
3993 and then Is_Itype (Designated_Type (Typ))
3994 then
3995 IR := Make_Itype_Reference (Sloc (Comp));
3996 Set_Itype (IR, Designated_Type (Typ));
3997 Append (IR, Result);
3998 end if;
3999
4000 Next_Component (Comp);
4001 end loop;
4002 end;
4003 end if;
4004 end if;
4005
4006 -- When a type is frozen, the first subtype of the type is frozen as
4007 -- well (RM 13.14(15)). This has to be done after freezing the type,
4008 -- since obviously the first subtype depends on its own base type.
4009
4010 if Is_Type (E) then
4011 Freeze_And_Append (First_Subtype (E), Loc, Result);
4012
4013 -- If we just froze a tagged non-class wide record, then freeze the
4014 -- corresponding class-wide type. This must be done after the tagged
4015 -- type itself is frozen, because the class-wide type refers to the
4016 -- tagged type which generates the class.
4017
4018 if Is_Tagged_Type (E)
4019 and then not Is_Class_Wide_Type (E)
4020 and then Present (Class_Wide_Type (E))
4021 then
4022 Freeze_And_Append (Class_Wide_Type (E), Loc, Result);
4023 end if;
4024 end if;
4025
4026 Check_Debug_Info_Needed (E);
4027
4028 -- Special handling for subprograms
4029
4030 if Is_Subprogram (E) then
4031
4032 -- If subprogram has address clause then reset Is_Public flag, since
4033 -- we do not want the backend to generate external references.
4034
4035 if Present (Address_Clause (E))
4036 and then not Is_Library_Level_Entity (E)
4037 then
4038 Set_Is_Public (E, False);
4039
4040 -- If no address clause and not intrinsic, then for imported
4041 -- subprogram in main unit, generate descriptor if we are in
4042 -- Propagate_Exceptions mode.
4043
4044 elsif Propagate_Exceptions
4045 and then Is_Imported (E)
4046 and then not Is_Intrinsic_Subprogram (E)
4047 and then Convention (E) /= Convention_Stubbed
4048 then
4049 if Result = No_List then
4050 Result := Empty_List;
4051 end if;
4052 end if;
4053 end if;
4054
4055 return Result;
4056 end Freeze_Entity;
4057
4058 -----------------------------
4059 -- Freeze_Enumeration_Type --
4060 -----------------------------
4061
4062 procedure Freeze_Enumeration_Type (Typ : Entity_Id) is
4063 begin
4064 -- By default, if no size clause is present, an enumeration type with
4065 -- Convention C is assumed to interface to a C enum, and has integer
4066 -- size. This applies to types. For subtypes, verify that its base
4067 -- type has no size clause either.
4068
4069 if Has_Foreign_Convention (Typ)
4070 and then not Has_Size_Clause (Typ)
4071 and then not Has_Size_Clause (Base_Type (Typ))
4072 and then Esize (Typ) < Standard_Integer_Size
4073 then
4074 Init_Esize (Typ, Standard_Integer_Size);
4075
4076 else
4077 -- If the enumeration type interfaces to C, and it has a size clause
4078 -- that specifies less than int size, it warrants a warning. The
4079 -- user may intend the C type to be an enum or a char, so this is
4080 -- not by itself an error that the Ada compiler can detect, but it
4081 -- it is a worth a heads-up. For Boolean and Character types we
4082 -- assume that the programmer has the proper C type in mind.
4083
4084 if Convention (Typ) = Convention_C
4085 and then Has_Size_Clause (Typ)
4086 and then Esize (Typ) /= Esize (Standard_Integer)
4087 and then not Is_Boolean_Type (Typ)
4088 and then not Is_Character_Type (Typ)
4089 then
4090 Error_Msg_N
4091 ("C enum types have the size of a C int?", Size_Clause (Typ));
4092 end if;
4093
4094 Adjust_Esize_For_Alignment (Typ);
4095 end if;
4096 end Freeze_Enumeration_Type;
4097
4098 -----------------------
4099 -- Freeze_Expression --
4100 -----------------------
4101
4102 procedure Freeze_Expression (N : Node_Id) is
4103 In_Spec_Exp : constant Boolean := In_Spec_Expression;
4104 Typ : Entity_Id;
4105 Nam : Entity_Id;
4106 Desig_Typ : Entity_Id;
4107 P : Node_Id;
4108 Parent_P : Node_Id;
4109
4110 Freeze_Outside : Boolean := False;
4111 -- This flag is set true if the entity must be frozen outside the
4112 -- current subprogram. This happens in the case of expander generated
4113 -- subprograms (_Init_Proc, _Input, _Output, _Read, _Write) which do
4114 -- not freeze all entities like other bodies, but which nevertheless
4115 -- may reference entities that have to be frozen before the body and
4116 -- obviously cannot be frozen inside the body.
4117
4118 function In_Exp_Body (N : Node_Id) return Boolean;
4119 -- Given an N_Handled_Sequence_Of_Statements node N, determines whether
4120 -- it is the handled statement sequence of an expander-generated
4121 -- subprogram (init proc, stream subprogram, or renaming as body).
4122 -- If so, this is not a freezing context.
4123
4124 -----------------
4125 -- In_Exp_Body --
4126 -----------------
4127
4128 function In_Exp_Body (N : Node_Id) return Boolean is
4129 P : Node_Id;
4130 Id : Entity_Id;
4131
4132 begin
4133 if Nkind (N) = N_Subprogram_Body then
4134 P := N;
4135 else
4136 P := Parent (N);
4137 end if;
4138
4139 if Nkind (P) /= N_Subprogram_Body then
4140 return False;
4141
4142 else
4143 Id := Defining_Unit_Name (Specification (P));
4144
4145 if Nkind (Id) = N_Defining_Identifier
4146 and then (Is_Init_Proc (Id) or else
4147 Is_TSS (Id, TSS_Stream_Input) or else
4148 Is_TSS (Id, TSS_Stream_Output) or else
4149 Is_TSS (Id, TSS_Stream_Read) or else
4150 Is_TSS (Id, TSS_Stream_Write) or else
4151 Nkind (Original_Node (P)) =
4152 N_Subprogram_Renaming_Declaration)
4153 then
4154 return True;
4155 else
4156 return False;
4157 end if;
4158 end if;
4159 end In_Exp_Body;
4160
4161 -- Start of processing for Freeze_Expression
4162
4163 begin
4164 -- Immediate return if freezing is inhibited. This flag is set by the
4165 -- analyzer to stop freezing on generated expressions that would cause
4166 -- freezing if they were in the source program, but which are not
4167 -- supposed to freeze, since they are created.
4168
4169 if Must_Not_Freeze (N) then
4170 return;
4171 end if;
4172
4173 -- If expression is non-static, then it does not freeze in a default
4174 -- expression, see section "Handling of Default Expressions" in the
4175 -- spec of package Sem for further details. Note that we have to
4176 -- make sure that we actually have a real expression (if we have
4177 -- a subtype indication, we can't test Is_Static_Expression!)
4178
4179 if In_Spec_Exp
4180 and then Nkind (N) in N_Subexpr
4181 and then not Is_Static_Expression (N)
4182 then
4183 return;
4184 end if;
4185
4186 -- Freeze type of expression if not frozen already
4187
4188 Typ := Empty;
4189
4190 if Nkind (N) in N_Has_Etype then
4191 if not Is_Frozen (Etype (N)) then
4192 Typ := Etype (N);
4193
4194 -- Base type may be an derived numeric type that is frozen at
4195 -- the point of declaration, but first_subtype is still unfrozen.
4196
4197 elsif not Is_Frozen (First_Subtype (Etype (N))) then
4198 Typ := First_Subtype (Etype (N));
4199 end if;
4200 end if;
4201
4202 -- For entity name, freeze entity if not frozen already. A special
4203 -- exception occurs for an identifier that did not come from source.
4204 -- We don't let such identifiers freeze a non-internal entity, i.e.
4205 -- an entity that did come from source, since such an identifier was
4206 -- generated by the expander, and cannot have any semantic effect on
4207 -- the freezing semantics. For example, this stops the parameter of
4208 -- an initialization procedure from freezing the variable.
4209
4210 if Is_Entity_Name (N)
4211 and then not Is_Frozen (Entity (N))
4212 and then (Nkind (N) /= N_Identifier
4213 or else Comes_From_Source (N)
4214 or else not Comes_From_Source (Entity (N)))
4215 then
4216 Nam := Entity (N);
4217 else
4218 Nam := Empty;
4219 end if;
4220
4221 -- For an allocator freeze designated type if not frozen already
4222
4223 -- For an aggregate whose component type is an access type, freeze the
4224 -- designated type now, so that its freeze does not appear within the
4225 -- loop that might be created in the expansion of the aggregate. If the
4226 -- designated type is a private type without full view, the expression
4227 -- cannot contain an allocator, so the type is not frozen.
4228
4229 -- For a function, we freeze the entity when the subprogram declaration
4230 -- is frozen, but a function call may appear in an initialization proc.
4231 -- before the declaration is frozen. We need to generate the extra
4232 -- formals, if any, to ensure that the expansion of the call includes
4233 -- the proper actuals. This only applies to Ada subprograms, not to
4234 -- imported ones.
4235
4236 Desig_Typ := Empty;
4237
4238 case Nkind (N) is
4239 when N_Allocator =>
4240 Desig_Typ := Designated_Type (Etype (N));
4241
4242 when N_Aggregate =>
4243 if Is_Array_Type (Etype (N))
4244 and then Is_Access_Type (Component_Type (Etype (N)))
4245 then
4246 Desig_Typ := Designated_Type (Component_Type (Etype (N)));
4247 end if;
4248
4249 when N_Selected_Component |
4250 N_Indexed_Component |
4251 N_Slice =>
4252
4253 if Is_Access_Type (Etype (Prefix (N))) then
4254 Desig_Typ := Designated_Type (Etype (Prefix (N)));
4255 end if;
4256
4257 when N_Identifier =>
4258 if Present (Nam)
4259 and then Ekind (Nam) = E_Function
4260 and then Nkind (Parent (N)) = N_Function_Call
4261 and then Convention (Nam) = Convention_Ada
4262 then
4263 Create_Extra_Formals (Nam);
4264 end if;
4265
4266 when others =>
4267 null;
4268 end case;
4269
4270 if Desig_Typ /= Empty
4271 and then (Is_Frozen (Desig_Typ)
4272 or else (not Is_Fully_Defined (Desig_Typ)))
4273 then
4274 Desig_Typ := Empty;
4275 end if;
4276
4277 -- All done if nothing needs freezing
4278
4279 if No (Typ)
4280 and then No (Nam)
4281 and then No (Desig_Typ)
4282 then
4283 return;
4284 end if;
4285
4286 -- Loop for looking at the right place to insert the freeze nodes,
4287 -- exiting from the loop when it is appropriate to insert the freeze
4288 -- node before the current node P.
4289
4290 -- Also checks some special exceptions to the freezing rules. These
4291 -- cases result in a direct return, bypassing the freeze action.
4292
4293 P := N;
4294 loop
4295 Parent_P := Parent (P);
4296
4297 -- If we don't have a parent, then we are not in a well-formed tree.
4298 -- This is an unusual case, but there are some legitimate situations
4299 -- in which this occurs, notably when the expressions in the range of
4300 -- a type declaration are resolved. We simply ignore the freeze
4301 -- request in this case. Is this right ???
4302
4303 if No (Parent_P) then
4304 return;
4305 end if;
4306
4307 -- See if we have got to an appropriate point in the tree
4308
4309 case Nkind (Parent_P) is
4310
4311 -- A special test for the exception of (RM 13.14(8)) for the case
4312 -- of per-object expressions (RM 3.8(18)) occurring in component
4313 -- definition or a discrete subtype definition. Note that we test
4314 -- for a component declaration which includes both cases we are
4315 -- interested in, and furthermore the tree does not have explicit
4316 -- nodes for either of these two constructs.
4317
4318 when N_Component_Declaration =>
4319
4320 -- The case we want to test for here is an identifier that is
4321 -- a per-object expression, this is either a discriminant that
4322 -- appears in a context other than the component declaration
4323 -- or it is a reference to the type of the enclosing construct.
4324
4325 -- For either of these cases, we skip the freezing
4326
4327 if not In_Spec_Expression
4328 and then Nkind (N) = N_Identifier
4329 and then (Present (Entity (N)))
4330 then
4331 -- We recognize the discriminant case by just looking for
4332 -- a reference to a discriminant. It can only be one for
4333 -- the enclosing construct. Skip freezing in this case.
4334
4335 if Ekind (Entity (N)) = E_Discriminant then
4336 return;
4337
4338 -- For the case of a reference to the enclosing record,
4339 -- (or task or protected type), we look for a type that
4340 -- matches the current scope.
4341
4342 elsif Entity (N) = Current_Scope then
4343 return;
4344 end if;
4345 end if;
4346
4347 -- If we have an enumeration literal that appears as the choice in
4348 -- the aggregate of an enumeration representation clause, then
4349 -- freezing does not occur (RM 13.14(10)).
4350
4351 when N_Enumeration_Representation_Clause =>
4352
4353 -- The case we are looking for is an enumeration literal
4354
4355 if (Nkind (N) = N_Identifier or Nkind (N) = N_Character_Literal)
4356 and then Is_Enumeration_Type (Etype (N))
4357 then
4358 -- If enumeration literal appears directly as the choice,
4359 -- do not freeze (this is the normal non-overloaded case)
4360
4361 if Nkind (Parent (N)) = N_Component_Association
4362 and then First (Choices (Parent (N))) = N
4363 then
4364 return;
4365
4366 -- If enumeration literal appears as the name of function
4367 -- which is the choice, then also do not freeze. This
4368 -- happens in the overloaded literal case, where the
4369 -- enumeration literal is temporarily changed to a function
4370 -- call for overloading analysis purposes.
4371
4372 elsif Nkind (Parent (N)) = N_Function_Call
4373 and then
4374 Nkind (Parent (Parent (N))) = N_Component_Association
4375 and then
4376 First (Choices (Parent (Parent (N)))) = Parent (N)
4377 then
4378 return;
4379 end if;
4380 end if;
4381
4382 -- Normally if the parent is a handled sequence of statements,
4383 -- then the current node must be a statement, and that is an
4384 -- appropriate place to insert a freeze node.
4385
4386 when N_Handled_Sequence_Of_Statements =>
4387
4388 -- An exception occurs when the sequence of statements is for
4389 -- an expander generated body that did not do the usual freeze
4390 -- all operation. In this case we usually want to freeze
4391 -- outside this body, not inside it, and we skip past the
4392 -- subprogram body that we are inside.
4393
4394 if In_Exp_Body (Parent_P) then
4395
4396 -- However, we *do* want to freeze at this point if we have
4397 -- an entity to freeze, and that entity is declared *inside*
4398 -- the body of the expander generated procedure. This case
4399 -- is recognized by the scope of the type, which is either
4400 -- the spec for some enclosing body, or (in the case of
4401 -- init_procs, for which there are no separate specs) the
4402 -- current scope.
4403
4404 declare
4405 Subp : constant Node_Id := Parent (Parent_P);
4406 Cspc : Entity_Id;
4407
4408 begin
4409 if Nkind (Subp) = N_Subprogram_Body then
4410 Cspc := Corresponding_Spec (Subp);
4411
4412 if (Present (Typ) and then Scope (Typ) = Cspc)
4413 or else
4414 (Present (Nam) and then Scope (Nam) = Cspc)
4415 then
4416 exit;
4417
4418 elsif Present (Typ)
4419 and then Scope (Typ) = Current_Scope
4420 and then Current_Scope = Defining_Entity (Subp)
4421 then
4422 exit;
4423 end if;
4424 end if;
4425 end;
4426
4427 -- If not that exception to the exception, then this is
4428 -- where we delay the freeze till outside the body.
4429
4430 Parent_P := Parent (Parent_P);
4431 Freeze_Outside := True;
4432
4433 -- Here if normal case where we are in handled statement
4434 -- sequence and want to do the insertion right there.
4435
4436 else
4437 exit;
4438 end if;
4439
4440 -- If parent is a body or a spec or a block, then the current node
4441 -- is a statement or declaration and we can insert the freeze node
4442 -- before it.
4443
4444 when N_Package_Specification |
4445 N_Package_Body |
4446 N_Subprogram_Body |
4447 N_Task_Body |
4448 N_Protected_Body |
4449 N_Entry_Body |
4450 N_Block_Statement => exit;
4451
4452 -- The expander is allowed to define types in any statements list,
4453 -- so any of the following parent nodes also mark a freezing point
4454 -- if the actual node is in a list of statements or declarations.
4455
4456 when N_Exception_Handler |
4457 N_If_Statement |
4458 N_Elsif_Part |
4459 N_Case_Statement_Alternative |
4460 N_Compilation_Unit_Aux |
4461 N_Selective_Accept |
4462 N_Accept_Alternative |
4463 N_Delay_Alternative |
4464 N_Conditional_Entry_Call |
4465 N_Entry_Call_Alternative |
4466 N_Triggering_Alternative |
4467 N_Abortable_Part |
4468 N_And_Then |
4469 N_Or_Else |
4470 N_Freeze_Entity =>
4471
4472 exit when Is_List_Member (P);
4473
4474 -- Note: The N_Loop_Statement is a special case. A type that
4475 -- appears in the source can never be frozen in a loop (this
4476 -- occurs only because of a loop expanded by the expander), so we
4477 -- keep on going. Otherwise we terminate the search. Same is true
4478 -- of any entity which comes from source. (if they have predefined
4479 -- type, that type does not appear to come from source, but the
4480 -- entity should not be frozen here).
4481
4482 when N_Loop_Statement =>
4483 exit when not Comes_From_Source (Etype (N))
4484 and then (No (Nam) or else not Comes_From_Source (Nam));
4485
4486 -- For all other cases, keep looking at parents
4487
4488 when others =>
4489 null;
4490 end case;
4491
4492 -- We fall through the case if we did not yet find the proper
4493 -- place in the free for inserting the freeze node, so climb!
4494
4495 P := Parent_P;
4496 end loop;
4497
4498 -- If the expression appears in a record or an initialization procedure,
4499 -- the freeze nodes are collected and attached to the current scope, to
4500 -- be inserted and analyzed on exit from the scope, to insure that
4501 -- generated entities appear in the correct scope. If the expression is
4502 -- a default for a discriminant specification, the scope is still void.
4503 -- The expression can also appear in the discriminant part of a private
4504 -- or concurrent type.
4505
4506 -- If the expression appears in a constrained subcomponent of an
4507 -- enclosing record declaration, the freeze nodes must be attached to
4508 -- the outer record type so they can eventually be placed in the
4509 -- enclosing declaration list.
4510
4511 -- The other case requiring this special handling is if we are in a
4512 -- default expression, since in that case we are about to freeze a
4513 -- static type, and the freeze scope needs to be the outer scope, not
4514 -- the scope of the subprogram with the default parameter.
4515
4516 -- For default expressions and other spec expressions in generic units,
4517 -- the Move_Freeze_Nodes mechanism (see sem_ch12.adb) takes care of
4518 -- placing them at the proper place, after the generic unit.
4519
4520 if (In_Spec_Exp and not Inside_A_Generic)
4521 or else Freeze_Outside
4522 or else (Is_Type (Current_Scope)
4523 and then (not Is_Concurrent_Type (Current_Scope)
4524 or else not Has_Completion (Current_Scope)))
4525 or else Ekind (Current_Scope) = E_Void
4526 then
4527 declare
4528 Loc : constant Source_Ptr := Sloc (Current_Scope);
4529 Freeze_Nodes : List_Id := No_List;
4530 Pos : Int := Scope_Stack.Last;
4531
4532 begin
4533 if Present (Desig_Typ) then
4534 Freeze_And_Append (Desig_Typ, Loc, Freeze_Nodes);
4535 end if;
4536
4537 if Present (Typ) then
4538 Freeze_And_Append (Typ, Loc, Freeze_Nodes);
4539 end if;
4540
4541 if Present (Nam) then
4542 Freeze_And_Append (Nam, Loc, Freeze_Nodes);
4543 end if;
4544
4545 -- The current scope may be that of a constrained component of
4546 -- an enclosing record declaration, which is above the current
4547 -- scope in the scope stack.
4548
4549 if Is_Record_Type (Scope (Current_Scope)) then
4550 Pos := Pos - 1;
4551 end if;
4552
4553 if Is_Non_Empty_List (Freeze_Nodes) then
4554 if No (Scope_Stack.Table (Pos).Pending_Freeze_Actions) then
4555 Scope_Stack.Table (Pos).Pending_Freeze_Actions :=
4556 Freeze_Nodes;
4557 else
4558 Append_List (Freeze_Nodes,
4559 Scope_Stack.Table (Pos).Pending_Freeze_Actions);
4560 end if;
4561 end if;
4562 end;
4563
4564 return;
4565 end if;
4566
4567 -- Now we have the right place to do the freezing. First, a special
4568 -- adjustment, if we are in spec-expression analysis mode, these freeze
4569 -- actions must not be thrown away (normally all inserted actions are
4570 -- thrown away in this mode. However, the freeze actions are from static
4571 -- expressions and one of the important reasons we are doing this
4572 -- special analysis is to get these freeze actions. Therefore we turn
4573 -- off the In_Spec_Expression mode to propagate these freeze actions.
4574 -- This also means they get properly analyzed and expanded.
4575
4576 In_Spec_Expression := False;
4577
4578 -- Freeze the designated type of an allocator (RM 13.14(13))
4579
4580 if Present (Desig_Typ) then
4581 Freeze_Before (P, Desig_Typ);
4582 end if;
4583
4584 -- Freeze type of expression (RM 13.14(10)). Note that we took care of
4585 -- the enumeration representation clause exception in the loop above.
4586
4587 if Present (Typ) then
4588 Freeze_Before (P, Typ);
4589 end if;
4590
4591 -- Freeze name if one is present (RM 13.14(11))
4592
4593 if Present (Nam) then
4594 Freeze_Before (P, Nam);
4595 end if;
4596
4597 -- Restore In_Spec_Expression flag
4598
4599 In_Spec_Expression := In_Spec_Exp;
4600 end Freeze_Expression;
4601
4602 -----------------------------
4603 -- Freeze_Fixed_Point_Type --
4604 -----------------------------
4605
4606 -- Certain fixed-point types and subtypes, including implicit base types
4607 -- and declared first subtypes, have not yet set up a range. This is
4608 -- because the range cannot be set until the Small and Size values are
4609 -- known, and these are not known till the type is frozen.
4610
4611 -- To signal this case, Scalar_Range contains an unanalyzed syntactic range
4612 -- whose bounds are unanalyzed real literals. This routine will recognize
4613 -- this case, and transform this range node into a properly typed range
4614 -- with properly analyzed and resolved values.
4615
4616 procedure Freeze_Fixed_Point_Type (Typ : Entity_Id) is
4617 Rng : constant Node_Id := Scalar_Range (Typ);
4618 Lo : constant Node_Id := Low_Bound (Rng);
4619 Hi : constant Node_Id := High_Bound (Rng);
4620 Btyp : constant Entity_Id := Base_Type (Typ);
4621 Brng : constant Node_Id := Scalar_Range (Btyp);
4622 BLo : constant Node_Id := Low_Bound (Brng);
4623 BHi : constant Node_Id := High_Bound (Brng);
4624 Small : constant Ureal := Small_Value (Typ);
4625 Loval : Ureal;
4626 Hival : Ureal;
4627 Atype : Entity_Id;
4628
4629 Actual_Size : Nat;
4630
4631 function Fsize (Lov, Hiv : Ureal) return Nat;
4632 -- Returns size of type with given bounds. Also leaves these
4633 -- bounds set as the current bounds of the Typ.
4634
4635 -----------
4636 -- Fsize --
4637 -----------
4638
4639 function Fsize (Lov, Hiv : Ureal) return Nat is
4640 begin
4641 Set_Realval (Lo, Lov);
4642 Set_Realval (Hi, Hiv);
4643 return Minimum_Size (Typ);
4644 end Fsize;
4645
4646 -- Start of processing for Freeze_Fixed_Point_Type
4647
4648 begin
4649 -- If Esize of a subtype has not previously been set, set it now
4650
4651 if Unknown_Esize (Typ) then
4652 Atype := Ancestor_Subtype (Typ);
4653
4654 if Present (Atype) then
4655 Set_Esize (Typ, Esize (Atype));
4656 else
4657 Set_Esize (Typ, Esize (Base_Type (Typ)));
4658 end if;
4659 end if;
4660
4661 -- Immediate return if the range is already analyzed. This means that
4662 -- the range is already set, and does not need to be computed by this
4663 -- routine.
4664
4665 if Analyzed (Rng) then
4666 return;
4667 end if;
4668
4669 -- Immediate return if either of the bounds raises Constraint_Error
4670
4671 if Raises_Constraint_Error (Lo)
4672 or else Raises_Constraint_Error (Hi)
4673 then
4674 return;
4675 end if;
4676
4677 Loval := Realval (Lo);
4678 Hival := Realval (Hi);
4679
4680 -- Ordinary fixed-point case
4681
4682 if Is_Ordinary_Fixed_Point_Type (Typ) then
4683
4684 -- For the ordinary fixed-point case, we are allowed to fudge the
4685 -- end-points up or down by small. Generally we prefer to fudge up,
4686 -- i.e. widen the bounds for non-model numbers so that the end points
4687 -- are included. However there are cases in which this cannot be
4688 -- done, and indeed cases in which we may need to narrow the bounds.
4689 -- The following circuit makes the decision.
4690
4691 -- Note: our terminology here is that Incl_EP means that the bounds
4692 -- are widened by Small if necessary to include the end points, and
4693 -- Excl_EP means that the bounds are narrowed by Small to exclude the
4694 -- end-points if this reduces the size.
4695
4696 -- Note that in the Incl case, all we care about is including the
4697 -- end-points. In the Excl case, we want to narrow the bounds as
4698 -- much as permitted by the RM, to give the smallest possible size.
4699
4700 Fudge : declare
4701 Loval_Incl_EP : Ureal;
4702 Hival_Incl_EP : Ureal;
4703
4704 Loval_Excl_EP : Ureal;
4705 Hival_Excl_EP : Ureal;
4706
4707 Size_Incl_EP : Nat;
4708 Size_Excl_EP : Nat;
4709
4710 Model_Num : Ureal;
4711 First_Subt : Entity_Id;
4712 Actual_Lo : Ureal;
4713 Actual_Hi : Ureal;
4714
4715 begin
4716 -- First step. Base types are required to be symmetrical. Right
4717 -- now, the base type range is a copy of the first subtype range.
4718 -- This will be corrected before we are done, but right away we
4719 -- need to deal with the case where both bounds are non-negative.
4720 -- In this case, we set the low bound to the negative of the high
4721 -- bound, to make sure that the size is computed to include the
4722 -- required sign. Note that we do not need to worry about the
4723 -- case of both bounds negative, because the sign will be dealt
4724 -- with anyway. Furthermore we can't just go making such a bound
4725 -- symmetrical, since in a twos-complement system, there is an
4726 -- extra negative value which could not be accommodated on the
4727 -- positive side.
4728
4729 if Typ = Btyp
4730 and then not UR_Is_Negative (Loval)
4731 and then Hival > Loval
4732 then
4733 Loval := -Hival;
4734 Set_Realval (Lo, Loval);
4735 end if;
4736
4737 -- Compute the fudged bounds. If the number is a model number,
4738 -- then we do nothing to include it, but we are allowed to backoff
4739 -- to the next adjacent model number when we exclude it. If it is
4740 -- not a model number then we straddle the two values with the
4741 -- model numbers on either side.
4742
4743 Model_Num := UR_Trunc (Loval / Small) * Small;
4744
4745 if Loval = Model_Num then
4746 Loval_Incl_EP := Model_Num;
4747 else
4748 Loval_Incl_EP := Model_Num - Small;
4749 end if;
4750
4751 -- The low value excluding the end point is Small greater, but
4752 -- we do not do this exclusion if the low value is positive,
4753 -- since it can't help the size and could actually hurt by
4754 -- crossing the high bound.
4755
4756 if UR_Is_Negative (Loval_Incl_EP) then
4757 Loval_Excl_EP := Loval_Incl_EP + Small;
4758
4759 -- If the value went from negative to zero, then we have the
4760 -- case where Loval_Incl_EP is the model number just below
4761 -- zero, so we want to stick to the negative value for the
4762 -- base type to maintain the condition that the size will
4763 -- include signed values.
4764
4765 if Typ = Btyp
4766 and then UR_Is_Zero (Loval_Excl_EP)
4767 then
4768 Loval_Excl_EP := Loval_Incl_EP;
4769 end if;
4770
4771 else
4772 Loval_Excl_EP := Loval_Incl_EP;
4773 end if;
4774
4775 -- Similar processing for upper bound and high value
4776
4777 Model_Num := UR_Trunc (Hival / Small) * Small;
4778
4779 if Hival = Model_Num then
4780 Hival_Incl_EP := Model_Num;
4781 else
4782 Hival_Incl_EP := Model_Num + Small;
4783 end if;
4784
4785 if UR_Is_Positive (Hival_Incl_EP) then
4786 Hival_Excl_EP := Hival_Incl_EP - Small;
4787 else
4788 Hival_Excl_EP := Hival_Incl_EP;
4789 end if;
4790
4791 -- One further adjustment is needed. In the case of subtypes, we
4792 -- cannot go outside the range of the base type, or we get
4793 -- peculiarities, and the base type range is already set. This
4794 -- only applies to the Incl values, since clearly the Excl values
4795 -- are already as restricted as they are allowed to be.
4796
4797 if Typ /= Btyp then
4798 Loval_Incl_EP := UR_Max (Loval_Incl_EP, Realval (BLo));
4799 Hival_Incl_EP := UR_Min (Hival_Incl_EP, Realval (BHi));
4800 end if;
4801
4802 -- Get size including and excluding end points
4803
4804 Size_Incl_EP := Fsize (Loval_Incl_EP, Hival_Incl_EP);
4805 Size_Excl_EP := Fsize (Loval_Excl_EP, Hival_Excl_EP);
4806
4807 -- No need to exclude end-points if it does not reduce size
4808
4809 if Fsize (Loval_Incl_EP, Hival_Excl_EP) = Size_Excl_EP then
4810 Loval_Excl_EP := Loval_Incl_EP;
4811 end if;
4812
4813 if Fsize (Loval_Excl_EP, Hival_Incl_EP) = Size_Excl_EP then
4814 Hival_Excl_EP := Hival_Incl_EP;
4815 end if;
4816
4817 -- Now we set the actual size to be used. We want to use the
4818 -- bounds fudged up to include the end-points but only if this
4819 -- can be done without violating a specifically given size
4820 -- size clause or causing an unacceptable increase in size.
4821
4822 -- Case of size clause given
4823
4824 if Has_Size_Clause (Typ) then
4825
4826 -- Use the inclusive size only if it is consistent with
4827 -- the explicitly specified size.
4828
4829 if Size_Incl_EP <= RM_Size (Typ) then
4830 Actual_Lo := Loval_Incl_EP;
4831 Actual_Hi := Hival_Incl_EP;
4832 Actual_Size := Size_Incl_EP;
4833
4834 -- If the inclusive size is too large, we try excluding
4835 -- the end-points (will be caught later if does not work).
4836
4837 else
4838 Actual_Lo := Loval_Excl_EP;
4839 Actual_Hi := Hival_Excl_EP;
4840 Actual_Size := Size_Excl_EP;
4841 end if;
4842
4843 -- Case of size clause not given
4844
4845 else
4846 -- If we have a base type whose corresponding first subtype
4847 -- has an explicit size that is large enough to include our
4848 -- end-points, then do so. There is no point in working hard
4849 -- to get a base type whose size is smaller than the specified
4850 -- size of the first subtype.
4851
4852 First_Subt := First_Subtype (Typ);
4853
4854 if Has_Size_Clause (First_Subt)
4855 and then Size_Incl_EP <= Esize (First_Subt)
4856 then
4857 Actual_Size := Size_Incl_EP;
4858 Actual_Lo := Loval_Incl_EP;
4859 Actual_Hi := Hival_Incl_EP;
4860
4861 -- If excluding the end-points makes the size smaller and
4862 -- results in a size of 8,16,32,64, then we take the smaller
4863 -- size. For the 64 case, this is compulsory. For the other
4864 -- cases, it seems reasonable. We like to include end points
4865 -- if we can, but not at the expense of moving to the next
4866 -- natural boundary of size.
4867
4868 elsif Size_Incl_EP /= Size_Excl_EP
4869 and then Addressable (Size_Excl_EP)
4870 then
4871 Actual_Size := Size_Excl_EP;
4872 Actual_Lo := Loval_Excl_EP;
4873 Actual_Hi := Hival_Excl_EP;
4874
4875 -- Otherwise we can definitely include the end points
4876
4877 else
4878 Actual_Size := Size_Incl_EP;
4879 Actual_Lo := Loval_Incl_EP;
4880 Actual_Hi := Hival_Incl_EP;
4881 end if;
4882
4883 -- One pathological case: normally we never fudge a low bound
4884 -- down, since it would seem to increase the size (if it has
4885 -- any effect), but for ranges containing single value, or no
4886 -- values, the high bound can be small too large. Consider:
4887
4888 -- type t is delta 2.0**(-14)
4889 -- range 131072.0 .. 0;
4890
4891 -- That lower bound is *just* outside the range of 32 bits, and
4892 -- does need fudging down in this case. Note that the bounds
4893 -- will always have crossed here, since the high bound will be
4894 -- fudged down if necessary, as in the case of:
4895
4896 -- type t is delta 2.0**(-14)
4897 -- range 131072.0 .. 131072.0;
4898
4899 -- So we detect the situation by looking for crossed bounds,
4900 -- and if the bounds are crossed, and the low bound is greater
4901 -- than zero, we will always back it off by small, since this
4902 -- is completely harmless.
4903
4904 if Actual_Lo > Actual_Hi then
4905 if UR_Is_Positive (Actual_Lo) then
4906 Actual_Lo := Loval_Incl_EP - Small;
4907 Actual_Size := Fsize (Actual_Lo, Actual_Hi);
4908
4909 -- And of course, we need to do exactly the same parallel
4910 -- fudge for flat ranges in the negative region.
4911
4912 elsif UR_Is_Negative (Actual_Hi) then
4913 Actual_Hi := Hival_Incl_EP + Small;
4914 Actual_Size := Fsize (Actual_Lo, Actual_Hi);
4915 end if;
4916 end if;
4917 end if;
4918
4919 Set_Realval (Lo, Actual_Lo);
4920 Set_Realval (Hi, Actual_Hi);
4921 end Fudge;
4922
4923 -- For the decimal case, none of this fudging is required, since there
4924 -- are no end-point problems in the decimal case (the end-points are
4925 -- always included).
4926
4927 else
4928 Actual_Size := Fsize (Loval, Hival);
4929 end if;
4930
4931 -- At this stage, the actual size has been calculated and the proper
4932 -- required bounds are stored in the low and high bounds.
4933
4934 if Actual_Size > 64 then
4935 Error_Msg_Uint_1 := UI_From_Int (Actual_Size);
4936 Error_Msg_N
4937 ("size required (^) for type& too large, maximum allowed is 64",
4938 Typ);
4939 Actual_Size := 64;
4940 end if;
4941
4942 -- Check size against explicit given size
4943
4944 if Has_Size_Clause (Typ) then
4945 if Actual_Size > RM_Size (Typ) then
4946 Error_Msg_Uint_1 := RM_Size (Typ);
4947 Error_Msg_Uint_2 := UI_From_Int (Actual_Size);
4948 Error_Msg_NE
4949 ("size given (^) for type& too small, minimum allowed is ^",
4950 Size_Clause (Typ), Typ);
4951
4952 else
4953 Actual_Size := UI_To_Int (Esize (Typ));
4954 end if;
4955
4956 -- Increase size to next natural boundary if no size clause given
4957
4958 else
4959 if Actual_Size <= 8 then
4960 Actual_Size := 8;
4961 elsif Actual_Size <= 16 then
4962 Actual_Size := 16;
4963 elsif Actual_Size <= 32 then
4964 Actual_Size := 32;
4965 else
4966 Actual_Size := 64;
4967 end if;
4968
4969 Init_Esize (Typ, Actual_Size);
4970 Adjust_Esize_For_Alignment (Typ);
4971 end if;
4972
4973 -- If we have a base type, then expand the bounds so that they extend to
4974 -- the full width of the allocated size in bits, to avoid junk range
4975 -- checks on intermediate computations.
4976
4977 if Base_Type (Typ) = Typ then
4978 Set_Realval (Lo, -(Small * (Uint_2 ** (Actual_Size - 1))));
4979 Set_Realval (Hi, (Small * (Uint_2 ** (Actual_Size - 1) - 1)));
4980 end if;
4981
4982 -- Final step is to reanalyze the bounds using the proper type
4983 -- and set the Corresponding_Integer_Value fields of the literals.
4984
4985 Set_Etype (Lo, Empty);
4986 Set_Analyzed (Lo, False);
4987 Analyze (Lo);
4988
4989 -- Resolve with universal fixed if the base type, and the base type if
4990 -- it is a subtype. Note we can't resolve the base type with itself,
4991 -- that would be a reference before definition.
4992
4993 if Typ = Btyp then
4994 Resolve (Lo, Universal_Fixed);
4995 else
4996 Resolve (Lo, Btyp);
4997 end if;
4998
4999 -- Set corresponding integer value for bound
5000
5001 Set_Corresponding_Integer_Value
5002 (Lo, UR_To_Uint (Realval (Lo) / Small));
5003
5004 -- Similar processing for high bound
5005
5006 Set_Etype (Hi, Empty);
5007 Set_Analyzed (Hi, False);
5008 Analyze (Hi);
5009
5010 if Typ = Btyp then
5011 Resolve (Hi, Universal_Fixed);
5012 else
5013 Resolve (Hi, Btyp);
5014 end if;
5015
5016 Set_Corresponding_Integer_Value
5017 (Hi, UR_To_Uint (Realval (Hi) / Small));
5018
5019 -- Set type of range to correspond to bounds
5020
5021 Set_Etype (Rng, Etype (Lo));
5022
5023 -- Set Esize to calculated size if not set already
5024
5025 if Unknown_Esize (Typ) then
5026 Init_Esize (Typ, Actual_Size);
5027 end if;
5028
5029 -- Set RM_Size if not already set. If already set, check value
5030
5031 declare
5032 Minsiz : constant Uint := UI_From_Int (Minimum_Size (Typ));
5033
5034 begin
5035 if RM_Size (Typ) /= Uint_0 then
5036 if RM_Size (Typ) < Minsiz then
5037 Error_Msg_Uint_1 := RM_Size (Typ);
5038 Error_Msg_Uint_2 := Minsiz;
5039 Error_Msg_NE
5040 ("size given (^) for type& too small, minimum allowed is ^",
5041 Size_Clause (Typ), Typ);
5042 end if;
5043
5044 else
5045 Set_RM_Size (Typ, Minsiz);
5046 end if;
5047 end;
5048 end Freeze_Fixed_Point_Type;
5049
5050 ------------------
5051 -- Freeze_Itype --
5052 ------------------
5053
5054 procedure Freeze_Itype (T : Entity_Id; N : Node_Id) is
5055 L : List_Id;
5056
5057 begin
5058 Set_Has_Delayed_Freeze (T);
5059 L := Freeze_Entity (T, Sloc (N));
5060
5061 if Is_Non_Empty_List (L) then
5062 Insert_Actions (N, L);
5063 end if;
5064 end Freeze_Itype;
5065
5066 --------------------------
5067 -- Freeze_Static_Object --
5068 --------------------------
5069
5070 procedure Freeze_Static_Object (E : Entity_Id) is
5071
5072 Cannot_Be_Static : exception;
5073 -- Exception raised if the type of a static object cannot be made
5074 -- static. This happens if the type depends on non-global objects.
5075
5076 procedure Ensure_Expression_Is_SA (N : Node_Id);
5077 -- Called to ensure that an expression used as part of a type definition
5078 -- is statically allocatable, which means that the expression type is
5079 -- statically allocatable, and the expression is either static, or a
5080 -- reference to a library level constant.
5081
5082 procedure Ensure_Type_Is_SA (Typ : Entity_Id);
5083 -- Called to mark a type as static, checking that it is possible
5084 -- to set the type as static. If it is not possible, then the
5085 -- exception Cannot_Be_Static is raised.
5086
5087 -----------------------------
5088 -- Ensure_Expression_Is_SA --
5089 -----------------------------
5090
5091 procedure Ensure_Expression_Is_SA (N : Node_Id) is
5092 Ent : Entity_Id;
5093
5094 begin
5095 Ensure_Type_Is_SA (Etype (N));
5096
5097 if Is_Static_Expression (N) then
5098 return;
5099
5100 elsif Nkind (N) = N_Identifier then
5101 Ent := Entity (N);
5102
5103 if Present (Ent)
5104 and then Ekind (Ent) = E_Constant
5105 and then Is_Library_Level_Entity (Ent)
5106 then
5107 return;
5108 end if;
5109 end if;
5110
5111 raise Cannot_Be_Static;
5112 end Ensure_Expression_Is_SA;
5113
5114 -----------------------
5115 -- Ensure_Type_Is_SA --
5116 -----------------------
5117
5118 procedure Ensure_Type_Is_SA (Typ : Entity_Id) is
5119 N : Node_Id;
5120 C : Entity_Id;
5121
5122 begin
5123 -- If type is library level, we are all set
5124
5125 if Is_Library_Level_Entity (Typ) then
5126 return;
5127 end if;
5128
5129 -- We are also OK if the type already marked as statically allocated,
5130 -- which means we processed it before.
5131
5132 if Is_Statically_Allocated (Typ) then
5133 return;
5134 end if;
5135
5136 -- Mark type as statically allocated
5137
5138 Set_Is_Statically_Allocated (Typ);
5139
5140 -- Check that it is safe to statically allocate this type
5141
5142 if Is_Scalar_Type (Typ) or else Is_Real_Type (Typ) then
5143 Ensure_Expression_Is_SA (Type_Low_Bound (Typ));
5144 Ensure_Expression_Is_SA (Type_High_Bound (Typ));
5145
5146 elsif Is_Array_Type (Typ) then
5147 N := First_Index (Typ);
5148 while Present (N) loop
5149 Ensure_Type_Is_SA (Etype (N));
5150 Next_Index (N);
5151 end loop;
5152
5153 Ensure_Type_Is_SA (Component_Type (Typ));
5154
5155 elsif Is_Access_Type (Typ) then
5156 if Ekind (Designated_Type (Typ)) = E_Subprogram_Type then
5157
5158 declare
5159 F : Entity_Id;
5160 T : constant Entity_Id := Etype (Designated_Type (Typ));
5161
5162 begin
5163 if T /= Standard_Void_Type then
5164 Ensure_Type_Is_SA (T);
5165 end if;
5166
5167 F := First_Formal (Designated_Type (Typ));
5168 while Present (F) loop
5169 Ensure_Type_Is_SA (Etype (F));
5170 Next_Formal (F);
5171 end loop;
5172 end;
5173
5174 else
5175 Ensure_Type_Is_SA (Designated_Type (Typ));
5176 end if;
5177
5178 elsif Is_Record_Type (Typ) then
5179 C := First_Entity (Typ);
5180 while Present (C) loop
5181 if Ekind (C) = E_Discriminant
5182 or else Ekind (C) = E_Component
5183 then
5184 Ensure_Type_Is_SA (Etype (C));
5185
5186 elsif Is_Type (C) then
5187 Ensure_Type_Is_SA (C);
5188 end if;
5189
5190 Next_Entity (C);
5191 end loop;
5192
5193 elsif Ekind (Typ) = E_Subprogram_Type then
5194 Ensure_Type_Is_SA (Etype (Typ));
5195
5196 C := First_Formal (Typ);
5197 while Present (C) loop
5198 Ensure_Type_Is_SA (Etype (C));
5199 Next_Formal (C);
5200 end loop;
5201
5202 else
5203 raise Cannot_Be_Static;
5204 end if;
5205 end Ensure_Type_Is_SA;
5206
5207 -- Start of processing for Freeze_Static_Object
5208
5209 begin
5210 Ensure_Type_Is_SA (Etype (E));
5211
5212 exception
5213 when Cannot_Be_Static =>
5214
5215 -- If the object that cannot be static is imported or exported, then
5216 -- issue an error message saying that this object cannot be imported
5217 -- or exported. If it has an address clause it is an overlay in the
5218 -- current partition and the static requirement is not relevant.
5219 -- Do not issue any error message when ignoring rep clauses.
5220
5221 if Ignore_Rep_Clauses then
5222 null;
5223
5224 elsif Is_Imported (E) then
5225 if No (Address_Clause (E)) then
5226 Error_Msg_N
5227 ("& cannot be imported (local type is not constant)", E);
5228 end if;
5229
5230 -- Otherwise must be exported, something is wrong if compiler
5231 -- is marking something as statically allocated which cannot be).
5232
5233 else pragma Assert (Is_Exported (E));
5234 Error_Msg_N
5235 ("& cannot be exported (local type is not constant)", E);
5236 end if;
5237 end Freeze_Static_Object;
5238
5239 -----------------------
5240 -- Freeze_Subprogram --
5241 -----------------------
5242
5243 procedure Freeze_Subprogram (E : Entity_Id) is
5244 Retype : Entity_Id;
5245 F : Entity_Id;
5246
5247 begin
5248 -- Subprogram may not have an address clause unless it is imported
5249
5250 if Present (Address_Clause (E)) then
5251 if not Is_Imported (E) then
5252 Error_Msg_N
5253 ("address clause can only be given " &
5254 "for imported subprogram",
5255 Name (Address_Clause (E)));
5256 end if;
5257 end if;
5258
5259 -- Reset the Pure indication on an imported subprogram unless an
5260 -- explicit Pure_Function pragma was present. We do this because
5261 -- otherwise it is an insidious error to call a non-pure function from
5262 -- pure unit and have calls mysteriously optimized away. What happens
5263 -- here is that the Import can bypass the normal check to ensure that
5264 -- pure units call only pure subprograms.
5265
5266 if Is_Imported (E)
5267 and then Is_Pure (E)
5268 and then not Has_Pragma_Pure_Function (E)
5269 then
5270 Set_Is_Pure (E, False);
5271 end if;
5272
5273 -- For non-foreign convention subprograms, this is where we create
5274 -- the extra formals (for accessibility level and constrained bit
5275 -- information). We delay this till the freeze point precisely so
5276 -- that we know the convention!
5277
5278 if not Has_Foreign_Convention (E) then
5279 Create_Extra_Formals (E);
5280 Set_Mechanisms (E);
5281
5282 -- If this is convention Ada and a Valued_Procedure, that's odd
5283
5284 if Ekind (E) = E_Procedure
5285 and then Is_Valued_Procedure (E)
5286 and then Convention (E) = Convention_Ada
5287 and then Warn_On_Export_Import
5288 then
5289 Error_Msg_N
5290 ("?Valued_Procedure has no effect for convention Ada", E);
5291 Set_Is_Valued_Procedure (E, False);
5292 end if;
5293
5294 -- Case of foreign convention
5295
5296 else
5297 Set_Mechanisms (E);
5298
5299 -- For foreign conventions, warn about return of an
5300 -- unconstrained array.
5301
5302 -- Note: we *do* allow a return by descriptor for the VMS case,
5303 -- though here there is probably more to be done ???
5304
5305 if Ekind (E) = E_Function then
5306 Retype := Underlying_Type (Etype (E));
5307
5308 -- If no return type, probably some other error, e.g. a
5309 -- missing full declaration, so ignore.
5310
5311 if No (Retype) then
5312 null;
5313
5314 -- If the return type is generic, we have emitted a warning
5315 -- earlier on, and there is nothing else to check here. Specific
5316 -- instantiations may lead to erroneous behavior.
5317
5318 elsif Is_Generic_Type (Etype (E)) then
5319 null;
5320
5321 -- Display warning if returning unconstrained array
5322
5323 elsif Is_Array_Type (Retype)
5324 and then not Is_Constrained (Retype)
5325
5326 -- Exclude cases where descriptor mechanism is set, since the
5327 -- VMS descriptor mechanisms allow such unconstrained returns.
5328
5329 and then Mechanism (E) not in Descriptor_Codes
5330
5331 -- Check appropriate warning is enabled (should we check for
5332 -- Warnings (Off) on specific entities here, probably so???)
5333
5334 and then Warn_On_Export_Import
5335
5336 -- Exclude the VM case, since return of unconstrained arrays
5337 -- is properly handled in both the JVM and .NET cases.
5338
5339 and then VM_Target = No_VM
5340 then
5341 Error_Msg_N
5342 ("?foreign convention function& should not return " &
5343 "unconstrained array", E);
5344 return;
5345 end if;
5346 end if;
5347
5348 -- If any of the formals for an exported foreign convention
5349 -- subprogram have defaults, then emit an appropriate warning since
5350 -- this is odd (default cannot be used from non-Ada code)
5351
5352 if Is_Exported (E) then
5353 F := First_Formal (E);
5354 while Present (F) loop
5355 if Warn_On_Export_Import
5356 and then Present (Default_Value (F))
5357 then
5358 Error_Msg_N
5359 ("?parameter cannot be defaulted in non-Ada call",
5360 Default_Value (F));
5361 end if;
5362
5363 Next_Formal (F);
5364 end loop;
5365 end if;
5366 end if;
5367
5368 -- For VMS, descriptor mechanisms for parameters are allowed only for
5369 -- imported/exported subprograms. Moreover, the NCA descriptor is not
5370 -- allowed for parameters of exported subprograms.
5371
5372 if OpenVMS_On_Target then
5373 if Is_Exported (E) then
5374 F := First_Formal (E);
5375 while Present (F) loop
5376 if Mechanism (F) = By_Descriptor_NCA then
5377 Error_Msg_N
5378 ("'N'C'A' descriptor for parameter not permitted", F);
5379 Error_Msg_N
5380 ("\can only be used for imported subprogram", F);
5381 end if;
5382
5383 Next_Formal (F);
5384 end loop;
5385
5386 elsif not Is_Imported (E) then
5387 F := First_Formal (E);
5388 while Present (F) loop
5389 if Mechanism (F) in Descriptor_Codes then
5390 Error_Msg_N
5391 ("descriptor mechanism for parameter not permitted", F);
5392 Error_Msg_N
5393 ("\can only be used for imported/exported subprogram", F);
5394 end if;
5395
5396 Next_Formal (F);
5397 end loop;
5398 end if;
5399 end if;
5400
5401 -- Pragma Inline_Always is disallowed for dispatching subprograms
5402 -- because the address of such subprograms is saved in the dispatch
5403 -- table to support dispatching calls, and dispatching calls cannot
5404 -- be inlined. This is consistent with the restriction against using
5405 -- 'Access or 'Address on an Inline_Always subprogram.
5406
5407 if Is_Dispatching_Operation (E)
5408 and then Has_Pragma_Inline_Always (E)
5409 then
5410 Error_Msg_N
5411 ("pragma Inline_Always not allowed for dispatching subprograms", E);
5412 end if;
5413
5414 -- Because of the implicit representation of inherited predefined
5415 -- operators in the front-end, the overriding status of the operation
5416 -- may be affected when a full view of a type is analyzed, and this is
5417 -- not captured by the analysis of the corresponding type declaration.
5418 -- Therefore the correctness of a not-overriding indicator must be
5419 -- rechecked when the subprogram is frozen.
5420
5421 if Nkind (E) = N_Defining_Operator_Symbol
5422 and then not Error_Posted (Parent (E))
5423 then
5424 Check_Overriding_Indicator (E, Empty, Is_Primitive (E));
5425 end if;
5426 end Freeze_Subprogram;
5427
5428 ----------------------
5429 -- Is_Fully_Defined --
5430 ----------------------
5431
5432 function Is_Fully_Defined (T : Entity_Id) return Boolean is
5433 begin
5434 if Ekind (T) = E_Class_Wide_Type then
5435 return Is_Fully_Defined (Etype (T));
5436
5437 elsif Is_Array_Type (T) then
5438 return Is_Fully_Defined (Component_Type (T));
5439
5440 elsif Is_Record_Type (T)
5441 and not Is_Private_Type (T)
5442 then
5443 -- Verify that the record type has no components with private types
5444 -- without completion.
5445
5446 declare
5447 Comp : Entity_Id;
5448
5449 begin
5450 Comp := First_Component (T);
5451 while Present (Comp) loop
5452 if not Is_Fully_Defined (Etype (Comp)) then
5453 return False;
5454 end if;
5455
5456 Next_Component (Comp);
5457 end loop;
5458 return True;
5459 end;
5460
5461 -- For the designated type of an access to subprogram, all types in
5462 -- the profile must be fully defined.
5463
5464 elsif Ekind (T) = E_Subprogram_Type then
5465 declare
5466 F : Entity_Id;
5467
5468 begin
5469 F := First_Formal (T);
5470 while Present (F) loop
5471 if not Is_Fully_Defined (Etype (F)) then
5472 return False;
5473 end if;
5474
5475 Next_Formal (F);
5476 end loop;
5477
5478 return Is_Fully_Defined (Etype (T));
5479 end;
5480
5481 else
5482 return not Is_Private_Type (T)
5483 or else Present (Full_View (Base_Type (T)));
5484 end if;
5485 end Is_Fully_Defined;
5486
5487 ---------------------------------
5488 -- Process_Default_Expressions --
5489 ---------------------------------
5490
5491 procedure Process_Default_Expressions
5492 (E : Entity_Id;
5493 After : in out Node_Id)
5494 is
5495 Loc : constant Source_Ptr := Sloc (E);
5496 Dbody : Node_Id;
5497 Formal : Node_Id;
5498 Dcopy : Node_Id;
5499 Dnam : Entity_Id;
5500
5501 begin
5502 Set_Default_Expressions_Processed (E);
5503
5504 -- A subprogram instance and its associated anonymous subprogram share
5505 -- their signature. The default expression functions are defined in the
5506 -- wrapper packages for the anonymous subprogram, and should not be
5507 -- generated again for the instance.
5508
5509 if Is_Generic_Instance (E)
5510 and then Present (Alias (E))
5511 and then Default_Expressions_Processed (Alias (E))
5512 then
5513 return;
5514 end if;
5515
5516 Formal := First_Formal (E);
5517 while Present (Formal) loop
5518 if Present (Default_Value (Formal)) then
5519
5520 -- We work with a copy of the default expression because we
5521 -- do not want to disturb the original, since this would mess
5522 -- up the conformance checking.
5523
5524 Dcopy := New_Copy_Tree (Default_Value (Formal));
5525
5526 -- The analysis of the expression may generate insert actions,
5527 -- which of course must not be executed. We wrap those actions
5528 -- in a procedure that is not called, and later on eliminated.
5529 -- The following cases have no side-effects, and are analyzed
5530 -- directly.
5531
5532 if Nkind (Dcopy) = N_Identifier
5533 or else Nkind (Dcopy) = N_Expanded_Name
5534 or else Nkind (Dcopy) = N_Integer_Literal
5535 or else (Nkind (Dcopy) = N_Real_Literal
5536 and then not Vax_Float (Etype (Dcopy)))
5537 or else Nkind (Dcopy) = N_Character_Literal
5538 or else Nkind (Dcopy) = N_String_Literal
5539 or else Known_Null (Dcopy)
5540 or else (Nkind (Dcopy) = N_Attribute_Reference
5541 and then
5542 Attribute_Name (Dcopy) = Name_Null_Parameter)
5543 then
5544
5545 -- If there is no default function, we must still do a full
5546 -- analyze call on the default value, to ensure that all error
5547 -- checks are performed, e.g. those associated with static
5548 -- evaluation. Note: this branch will always be taken if the
5549 -- analyzer is turned off (but we still need the error checks).
5550
5551 -- Note: the setting of parent here is to meet the requirement
5552 -- that we can only analyze the expression while attached to
5553 -- the tree. Really the requirement is that the parent chain
5554 -- be set, we don't actually need to be in the tree.
5555
5556 Set_Parent (Dcopy, Declaration_Node (Formal));
5557 Analyze (Dcopy);
5558
5559 -- Default expressions are resolved with their own type if the
5560 -- context is generic, to avoid anomalies with private types.
5561
5562 if Ekind (Scope (E)) = E_Generic_Package then
5563 Resolve (Dcopy);
5564 else
5565 Resolve (Dcopy, Etype (Formal));
5566 end if;
5567
5568 -- If that resolved expression will raise constraint error,
5569 -- then flag the default value as raising constraint error.
5570 -- This allows a proper error message on the calls.
5571
5572 if Raises_Constraint_Error (Dcopy) then
5573 Set_Raises_Constraint_Error (Default_Value (Formal));
5574 end if;
5575
5576 -- If the default is a parameterless call, we use the name of
5577 -- the called function directly, and there is no body to build.
5578
5579 elsif Nkind (Dcopy) = N_Function_Call
5580 and then No (Parameter_Associations (Dcopy))
5581 then
5582 null;
5583
5584 -- Else construct and analyze the body of a wrapper procedure
5585 -- that contains an object declaration to hold the expression.
5586 -- Given that this is done only to complete the analysis, it
5587 -- simpler to build a procedure than a function which might
5588 -- involve secondary stack expansion.
5589
5590 else
5591 Dnam := Make_Temporary (Loc, 'D');
5592
5593 Dbody :=
5594 Make_Subprogram_Body (Loc,
5595 Specification =>
5596 Make_Procedure_Specification (Loc,
5597 Defining_Unit_Name => Dnam),
5598
5599 Declarations => New_List (
5600 Make_Object_Declaration (Loc,
5601 Defining_Identifier =>
5602 Make_Defining_Identifier (Loc,
5603 New_Internal_Name ('T')),
5604 Object_Definition =>
5605 New_Occurrence_Of (Etype (Formal), Loc),
5606 Expression => New_Copy_Tree (Dcopy))),
5607
5608 Handled_Statement_Sequence =>
5609 Make_Handled_Sequence_Of_Statements (Loc,
5610 Statements => New_List));
5611
5612 Set_Scope (Dnam, Scope (E));
5613 Set_Assignment_OK (First (Declarations (Dbody)));
5614 Set_Is_Eliminated (Dnam);
5615 Insert_After (After, Dbody);
5616 Analyze (Dbody);
5617 After := Dbody;
5618 end if;
5619 end if;
5620
5621 Next_Formal (Formal);
5622 end loop;
5623 end Process_Default_Expressions;
5624
5625 ----------------------------------------
5626 -- Set_Component_Alignment_If_Not_Set --
5627 ----------------------------------------
5628
5629 procedure Set_Component_Alignment_If_Not_Set (Typ : Entity_Id) is
5630 begin
5631 -- Ignore if not base type, subtypes don't need anything
5632
5633 if Typ /= Base_Type (Typ) then
5634 return;
5635 end if;
5636
5637 -- Do not override existing representation
5638
5639 if Is_Packed (Typ) then
5640 return;
5641
5642 elsif Has_Specified_Layout (Typ) then
5643 return;
5644
5645 elsif Component_Alignment (Typ) /= Calign_Default then
5646 return;
5647
5648 else
5649 Set_Component_Alignment
5650 (Typ, Scope_Stack.Table
5651 (Scope_Stack.Last).Component_Alignment_Default);
5652 end if;
5653 end Set_Component_Alignment_If_Not_Set;
5654
5655 ------------------
5656 -- Undelay_Type --
5657 ------------------
5658
5659 procedure Undelay_Type (T : Entity_Id) is
5660 begin
5661 Set_Has_Delayed_Freeze (T, False);
5662 Set_Freeze_Node (T, Empty);
5663
5664 -- Since we don't want T to have a Freeze_Node, we don't want its
5665 -- Full_View or Corresponding_Record_Type to have one either.
5666
5667 -- ??? Fundamentally, this whole handling is a kludge. What we really
5668 -- want is to be sure that for an Itype that's part of record R and is a
5669 -- subtype of type T, that it's frozen after the later of the freeze
5670 -- points of R and T. We have no way of doing that directly, so what we
5671 -- do is force most such Itypes to be frozen as part of freezing R via
5672 -- this procedure and only delay the ones that need to be delayed
5673 -- (mostly the designated types of access types that are defined as part
5674 -- of the record).
5675
5676 if Is_Private_Type (T)
5677 and then Present (Full_View (T))
5678 and then Is_Itype (Full_View (T))
5679 and then Is_Record_Type (Scope (Full_View (T)))
5680 then
5681 Undelay_Type (Full_View (T));
5682 end if;
5683
5684 if Is_Concurrent_Type (T)
5685 and then Present (Corresponding_Record_Type (T))
5686 and then Is_Itype (Corresponding_Record_Type (T))
5687 and then Is_Record_Type (Scope (Corresponding_Record_Type (T)))
5688 then
5689 Undelay_Type (Corresponding_Record_Type (T));
5690 end if;
5691 end Undelay_Type;
5692
5693 ------------------
5694 -- Warn_Overlay --
5695 ------------------
5696
5697 procedure Warn_Overlay
5698 (Expr : Node_Id;
5699 Typ : Entity_Id;
5700 Nam : Entity_Id)
5701 is
5702 Ent : constant Entity_Id := Entity (Nam);
5703 -- The object to which the address clause applies
5704
5705 Init : Node_Id;
5706 Old : Entity_Id := Empty;
5707 Decl : Node_Id;
5708
5709 begin
5710 -- No warning if address clause overlay warnings are off
5711
5712 if not Address_Clause_Overlay_Warnings then
5713 return;
5714 end if;
5715
5716 -- No warning if there is an explicit initialization
5717
5718 Init := Original_Node (Expression (Declaration_Node (Ent)));
5719
5720 if Present (Init) and then Comes_From_Source (Init) then
5721 return;
5722 end if;
5723
5724 -- We only give the warning for non-imported entities of a type for
5725 -- which a non-null base init proc is defined, or for objects of access
5726 -- types with implicit null initialization, or when Normalize_Scalars
5727 -- applies and the type is scalar or a string type (the latter being
5728 -- tested for because predefined String types are initialized by inline
5729 -- code rather than by an init_proc). Note that we do not give the
5730 -- warning for Initialize_Scalars, since we suppressed initialization
5731 -- in this case.
5732
5733 if Present (Expr)
5734 and then not Is_Imported (Ent)
5735 and then (Has_Non_Null_Base_Init_Proc (Typ)
5736 or else Is_Access_Type (Typ)
5737 or else (Normalize_Scalars
5738 and then (Is_Scalar_Type (Typ)
5739 or else Is_String_Type (Typ))))
5740 then
5741 if Nkind (Expr) = N_Attribute_Reference
5742 and then Is_Entity_Name (Prefix (Expr))
5743 then
5744 Old := Entity (Prefix (Expr));
5745
5746 elsif Is_Entity_Name (Expr)
5747 and then Ekind (Entity (Expr)) = E_Constant
5748 then
5749 Decl := Declaration_Node (Entity (Expr));
5750
5751 if Nkind (Decl) = N_Object_Declaration
5752 and then Present (Expression (Decl))
5753 and then Nkind (Expression (Decl)) = N_Attribute_Reference
5754 and then Is_Entity_Name (Prefix (Expression (Decl)))
5755 then
5756 Old := Entity (Prefix (Expression (Decl)));
5757
5758 elsif Nkind (Expr) = N_Function_Call then
5759 return;
5760 end if;
5761
5762 -- A function call (most likely to To_Address) is probably not an
5763 -- overlay, so skip warning. Ditto if the function call was inlined
5764 -- and transformed into an entity.
5765
5766 elsif Nkind (Original_Node (Expr)) = N_Function_Call then
5767 return;
5768 end if;
5769
5770 Decl := Next (Parent (Expr));
5771
5772 -- If a pragma Import follows, we assume that it is for the current
5773 -- target of the address clause, and skip the warning.
5774
5775 if Present (Decl)
5776 and then Nkind (Decl) = N_Pragma
5777 and then Pragma_Name (Decl) = Name_Import
5778 then
5779 return;
5780 end if;
5781
5782 if Present (Old) then
5783 Error_Msg_Node_2 := Old;
5784 Error_Msg_N
5785 ("default initialization of & may modify &?",
5786 Nam);
5787 else
5788 Error_Msg_N
5789 ("default initialization of & may modify overlaid storage?",
5790 Nam);
5791 end if;
5792
5793 -- Add friendly warning if initialization comes from a packed array
5794 -- component.
5795
5796 if Is_Record_Type (Typ) then
5797 declare
5798 Comp : Entity_Id;
5799
5800 begin
5801 Comp := First_Component (Typ);
5802 while Present (Comp) loop
5803 if Nkind (Parent (Comp)) = N_Component_Declaration
5804 and then Present (Expression (Parent (Comp)))
5805 then
5806 exit;
5807 elsif Is_Array_Type (Etype (Comp))
5808 and then Present (Packed_Array_Type (Etype (Comp)))
5809 then
5810 Error_Msg_NE
5811 ("\packed array component& " &
5812 "will be initialized to zero?",
5813 Nam, Comp);
5814 exit;
5815 else
5816 Next_Component (Comp);
5817 end if;
5818 end loop;
5819 end;
5820 end if;
5821
5822 Error_Msg_N
5823 ("\use pragma Import for & to " &
5824 "suppress initialization (RM B.1(24))?",
5825 Nam);
5826 end if;
5827 end Warn_Overlay;
5828
5829 end Freeze;
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