[multiple changes]
[gcc.git] / gcc / ada / freeze.adb
1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- F R E E Z E --
6 -- --
7 -- B o d y --
8 -- --
9 -- Copyright (C) 1992-2011, 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. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
20 -- --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
23 -- --
24 ------------------------------------------------------------------------------
25
26 with Atree; use Atree;
27 with Debug; use Debug;
28 with Einfo; use Einfo;
29 with Elists; use Elists;
30 with Errout; use Errout;
31 with Exp_Ch3; use Exp_Ch3;
32 with Exp_Ch7; use Exp_Ch7;
33 with Exp_Disp; use Exp_Disp;
34 with Exp_Pakd; use Exp_Pakd;
35 with Exp_Util; use Exp_Util;
36 with Exp_Tss; use Exp_Tss;
37 with Layout; use Layout;
38 with Lib; use Lib;
39 with Namet; use Namet;
40 with Nlists; use Nlists;
41 with Nmake; use Nmake;
42 with Opt; use Opt;
43 with Restrict; use Restrict;
44 with Rident; use Rident;
45 with Sem; use Sem;
46 with Sem_Aux; use Sem_Aux;
47 with Sem_Cat; use Sem_Cat;
48 with Sem_Ch6; use Sem_Ch6;
49 with Sem_Ch7; use Sem_Ch7;
50 with Sem_Ch8; use Sem_Ch8;
51 with Sem_Ch13; use Sem_Ch13;
52 with Sem_Eval; use Sem_Eval;
53 with Sem_Mech; use Sem_Mech;
54 with Sem_Prag; use Sem_Prag;
55 with Sem_Res; use Sem_Res;
56 with Sem_Util; use Sem_Util;
57 with Sinfo; use Sinfo;
58 with Snames; use Snames;
59 with Stand; use Stand;
60 with Targparm; use Targparm;
61 with Tbuild; use Tbuild;
62 with Ttypes; use Ttypes;
63 with Uintp; use Uintp;
64 with Urealp; use Urealp;
65
66 package body Freeze is
67
68 -----------------------
69 -- Local Subprograms --
70 -----------------------
71
72 procedure Adjust_Esize_For_Alignment (Typ : Entity_Id);
73 -- Typ is a type that is being frozen. If no size clause is given,
74 -- but a default Esize has been computed, then this default Esize is
75 -- adjusted up if necessary to be consistent with a given alignment,
76 -- but never to a value greater than Long_Long_Integer'Size. This
77 -- is used for all discrete types and for fixed-point types.
78
79 procedure Build_And_Analyze_Renamed_Body
80 (Decl : Node_Id;
81 New_S : Entity_Id;
82 After : in out Node_Id);
83 -- Build body for a renaming declaration, insert in tree and analyze
84
85 procedure Check_Address_Clause (E : Entity_Id);
86 -- Apply legality checks to address clauses for object declarations,
87 -- at the point the object is frozen.
88
89 procedure Check_Strict_Alignment (E : Entity_Id);
90 -- E is a base type. If E is tagged or has a component that is aliased
91 -- or tagged or contains something this is aliased or tagged, set
92 -- Strict_Alignment.
93
94 procedure Check_Unsigned_Type (E : Entity_Id);
95 pragma Inline (Check_Unsigned_Type);
96 -- If E is a fixed-point or discrete type, then all the necessary work
97 -- to freeze it is completed except for possible setting of the flag
98 -- Is_Unsigned_Type, which is done by this procedure. The call has no
99 -- effect if the entity E is not a discrete or fixed-point type.
100
101 procedure Freeze_And_Append
102 (Ent : Entity_Id;
103 N : Node_Id;
104 Result : in out List_Id);
105 -- Freezes Ent using Freeze_Entity, and appends the resulting list of
106 -- nodes to Result, modifying Result from No_List if necessary. N has
107 -- the same usage as in Freeze_Entity.
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 of
142 -- default expressions at the point where all types are known to be frozen.
143 -- The expressions must be analyzed in full, to make sure that all error
144 -- processing is done (they have only been pre-analyzed). If the expression
145 -- is not an entity or literal, its analysis may generate code which must
146 -- not be executed. In that case we build a function body to hold that
147 -- code. This wrapper function serves no other purpose (it used to be
148 -- called to evaluate the default, but now the default is inlined at each
149 -- 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 sets
153 -- the default component alignment from the scope stack values if the
154 -- 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. We don't want
166 -- this to have a Freeze_Node, so ensure it doesn't. Do the same for any
167 -- 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 intrinsic 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. This is not done in the case
365 -- where the subprogram is an instantiation because the actual proper
366 -- body has not been built yet.
367
368 if Ekind_In (Old_S, E_Function, E_Procedure)
369 and then Nkind (Decl) = N_Subprogram_Declaration
370 and then not Is_Generic_Instance (Old_S)
371 then
372 Set_Body_To_Inline (Decl, Old_S);
373 end if;
374
375 -- The body generated for this renaming is an internal artifact, and
376 -- does not constitute a freeze point for the called entity.
377
378 Set_Must_Not_Freeze (Call_Name);
379
380 Formal := First_Formal (Defining_Entity (Decl));
381
382 if Present (Pref) then
383 declare
384 Pref_Type : constant Entity_Id := Etype (Pref);
385 Form_Type : constant Entity_Id := Etype (First_Formal (Old_S));
386
387 begin
388 -- The controlling formal may be an access parameter, or the
389 -- actual may be an access value, so adjust accordingly.
390
391 if Is_Access_Type (Pref_Type)
392 and then not Is_Access_Type (Form_Type)
393 then
394 Actuals := New_List
395 (Make_Explicit_Dereference (Loc, Relocate_Node (Pref)));
396
397 elsif Is_Access_Type (Form_Type)
398 and then not Is_Access_Type (Pref)
399 then
400 Actuals := New_List
401 (Make_Attribute_Reference (Loc,
402 Attribute_Name => Name_Access,
403 Prefix => Relocate_Node (Pref)));
404 else
405 Actuals := New_List (Pref);
406 end if;
407 end;
408
409 elsif Present (Formal) then
410 Actuals := New_List;
411
412 else
413 Actuals := No_List;
414 end if;
415
416 if Present (Formal) then
417 while Present (Formal) loop
418 Append (New_Reference_To (Formal, Loc), Actuals);
419 Next_Formal (Formal);
420 end loop;
421 end if;
422
423 -- If the renamed entity is an entry, inherit its profile. For other
424 -- renamings as bodies, both profiles must be subtype conformant, so it
425 -- is not necessary to replace the profile given in the declaration.
426 -- However, default values that are aggregates are rewritten when
427 -- partially analyzed, so we recover the original aggregate to insure
428 -- that subsequent conformity checking works. Similarly, if the default
429 -- expression was constant-folded, recover the original expression.
430
431 Formal := First_Formal (Defining_Entity (Decl));
432
433 if Present (Formal) then
434 O_Formal := First_Formal (Old_S);
435 Param_Spec := First (Parameter_Specifications (Spec));
436 while Present (Formal) loop
437 if Is_Entry (Old_S) then
438 if Nkind (Parameter_Type (Param_Spec)) /=
439 N_Access_Definition
440 then
441 Set_Etype (Formal, Etype (O_Formal));
442 Set_Entity (Parameter_Type (Param_Spec), Etype (O_Formal));
443 end if;
444
445 elsif Nkind (Default_Value (O_Formal)) = N_Aggregate
446 or else Nkind (Original_Node (Default_Value (O_Formal))) /=
447 Nkind (Default_Value (O_Formal))
448 then
449 Set_Expression (Param_Spec,
450 New_Copy_Tree (Original_Node (Default_Value (O_Formal))));
451 end if;
452
453 Next_Formal (Formal);
454 Next_Formal (O_Formal);
455 Next (Param_Spec);
456 end loop;
457 end if;
458
459 -- If the renamed entity is a function, the generated body contains a
460 -- return statement. Otherwise, build a procedure call. If the entity is
461 -- an entry, subsequent analysis of the call will transform it into the
462 -- proper entry or protected operation call. If the renamed entity is
463 -- a character literal, return it directly.
464
465 if Ekind (Old_S) = E_Function
466 or else Ekind (Old_S) = E_Operator
467 or else (Ekind (Old_S) = E_Subprogram_Type
468 and then Etype (Old_S) /= Standard_Void_Type)
469 then
470 Call_Node :=
471 Make_Simple_Return_Statement (Loc,
472 Expression =>
473 Make_Function_Call (Loc,
474 Name => Call_Name,
475 Parameter_Associations => Actuals));
476
477 elsif Ekind (Old_S) = E_Enumeration_Literal then
478 Call_Node :=
479 Make_Simple_Return_Statement (Loc,
480 Expression => New_Occurrence_Of (Old_S, Loc));
481
482 elsif Nkind (Nam) = N_Character_Literal then
483 Call_Node :=
484 Make_Simple_Return_Statement (Loc,
485 Expression => Call_Name);
486
487 else
488 Call_Node :=
489 Make_Procedure_Call_Statement (Loc,
490 Name => Call_Name,
491 Parameter_Associations => Actuals);
492 end if;
493
494 -- Create entities for subprogram body and formals
495
496 Set_Defining_Unit_Name (Spec,
497 Make_Defining_Identifier (Loc, Chars => Chars (New_S)));
498
499 Param_Spec := First (Parameter_Specifications (Spec));
500 while Present (Param_Spec) loop
501 Set_Defining_Identifier (Param_Spec,
502 Make_Defining_Identifier (Loc,
503 Chars => Chars (Defining_Identifier (Param_Spec))));
504 Next (Param_Spec);
505 end loop;
506
507 Body_Node :=
508 Make_Subprogram_Body (Loc,
509 Specification => Spec,
510 Declarations => New_List,
511 Handled_Statement_Sequence =>
512 Make_Handled_Sequence_Of_Statements (Loc,
513 Statements => New_List (Call_Node)));
514
515 if Nkind (Decl) /= N_Subprogram_Declaration then
516 Rewrite (N,
517 Make_Subprogram_Declaration (Loc,
518 Specification => Specification (N)));
519 end if;
520
521 -- Link the body to the entity whose declaration it completes. If
522 -- the body is analyzed when the renamed entity is frozen, it may
523 -- be necessary to restore the proper scope (see package Exp_Ch13).
524
525 if Nkind (N) = N_Subprogram_Renaming_Declaration
526 and then Present (Corresponding_Spec (N))
527 then
528 Set_Corresponding_Spec (Body_Node, Corresponding_Spec (N));
529 else
530 Set_Corresponding_Spec (Body_Node, New_S);
531 end if;
532
533 return Body_Node;
534 end Build_Renamed_Body;
535
536 --------------------------
537 -- Check_Address_Clause --
538 --------------------------
539
540 procedure Check_Address_Clause (E : Entity_Id) is
541 Addr : constant Node_Id := Address_Clause (E);
542 Expr : Node_Id;
543 Decl : constant Node_Id := Declaration_Node (E);
544 Typ : constant Entity_Id := Etype (E);
545
546 begin
547 if Present (Addr) then
548 Expr := Expression (Addr);
549
550 if Needs_Constant_Address (Decl, Typ) then
551 Check_Constant_Address_Clause (Expr, E);
552
553 -- Has_Delayed_Freeze was set on E when the address clause was
554 -- analyzed. Reset the flag now unless freeze actions were
555 -- attached to it in the mean time.
556
557 if No (Freeze_Node (E)) then
558 Set_Has_Delayed_Freeze (E, False);
559 end if;
560 end if;
561
562 -- If Rep_Clauses are to be ignored, remove address clause from
563 -- list attached to entity, because it may be illegal for gigi,
564 -- for example by breaking order of elaboration..
565
566 if Ignore_Rep_Clauses then
567 declare
568 Rep : Node_Id;
569
570 begin
571 Rep := First_Rep_Item (E);
572
573 if Rep = Addr then
574 Set_First_Rep_Item (E, Next_Rep_Item (Addr));
575
576 else
577 while Present (Rep)
578 and then Next_Rep_Item (Rep) /= Addr
579 loop
580 Rep := Next_Rep_Item (Rep);
581 end loop;
582 end if;
583
584 if Present (Rep) then
585 Set_Next_Rep_Item (Rep, Next_Rep_Item (Addr));
586 end if;
587 end;
588
589 Rewrite (Addr, Make_Null_Statement (Sloc (E)));
590
591 elsif not Error_Posted (Expr)
592 and then not Needs_Finalization (Typ)
593 then
594 Warn_Overlay (Expr, Typ, Name (Addr));
595 end if;
596 end if;
597 end Check_Address_Clause;
598
599 -----------------------------
600 -- Check_Compile_Time_Size --
601 -----------------------------
602
603 procedure Check_Compile_Time_Size (T : Entity_Id) is
604
605 procedure Set_Small_Size (T : Entity_Id; S : Uint);
606 -- Sets the compile time known size (32 bits or less) in the Esize
607 -- field, of T checking for a size clause that was given which attempts
608 -- to give a smaller size, and also checking for an alignment clause.
609
610 function Size_Known (T : Entity_Id) return Boolean;
611 -- Recursive function that does all the work
612
613 function Static_Discriminated_Components (T : Entity_Id) return Boolean;
614 -- If T is a constrained subtype, its size is not known if any of its
615 -- discriminant constraints is not static and it is not a null record.
616 -- The test is conservative and doesn't check that the components are
617 -- in fact constrained by non-static discriminant values. Could be made
618 -- more precise ???
619
620 --------------------
621 -- Set_Small_Size --
622 --------------------
623
624 procedure Set_Small_Size (T : Entity_Id; S : Uint) is
625 begin
626 if S > 32 then
627 return;
628
629 -- Check for bad size clause given
630
631 elsif Has_Size_Clause (T) then
632 if RM_Size (T) < S then
633 Error_Msg_Uint_1 := S;
634 Error_Msg_NE
635 ("size for& too small, minimum allowed is ^",
636 Size_Clause (T), T);
637 end if;
638
639 -- Set size if not set already
640
641 elsif Unknown_RM_Size (T) then
642 Set_RM_Size (T, S);
643 end if;
644 end Set_Small_Size;
645
646 ----------------
647 -- Size_Known --
648 ----------------
649
650 function Size_Known (T : Entity_Id) return Boolean is
651 Index : Entity_Id;
652 Comp : Entity_Id;
653 Ctyp : Entity_Id;
654 Low : Node_Id;
655 High : Node_Id;
656
657 begin
658 if Size_Known_At_Compile_Time (T) then
659 return True;
660
661 -- Always True for scalar types. This is true even for generic formal
662 -- scalar types. We used to return False in the latter case, but the
663 -- size is known at compile time, even in the template, we just do
664 -- not know the exact size but that's not the point of this routine.
665
666 elsif Is_Scalar_Type (T)
667 or else Is_Task_Type (T)
668 then
669 return True;
670
671 -- Array types
672
673 elsif Is_Array_Type (T) then
674
675 -- String literals always have known size, and we can set it
676
677 if Ekind (T) = E_String_Literal_Subtype then
678 Set_Small_Size (T, Component_Size (T)
679 * String_Literal_Length (T));
680 return True;
681
682 -- Unconstrained types never have known at compile time size
683
684 elsif not Is_Constrained (T) then
685 return False;
686
687 -- Don't do any recursion on type with error posted, since we may
688 -- have a malformed type that leads us into a loop.
689
690 elsif Error_Posted (T) then
691 return False;
692
693 -- Otherwise if component size unknown, then array size unknown
694
695 elsif not Size_Known (Component_Type (T)) then
696 return False;
697 end if;
698
699 -- Check for all indexes static, and also compute possible size
700 -- (in case it is less than 32 and may be packable).
701
702 declare
703 Esiz : Uint := Component_Size (T);
704 Dim : Uint;
705
706 begin
707 Index := First_Index (T);
708 while Present (Index) loop
709 if Nkind (Index) = N_Range then
710 Get_Index_Bounds (Index, Low, High);
711
712 elsif Error_Posted (Scalar_Range (Etype (Index))) then
713 return False;
714
715 else
716 Low := Type_Low_Bound (Etype (Index));
717 High := Type_High_Bound (Etype (Index));
718 end if;
719
720 if not Compile_Time_Known_Value (Low)
721 or else not Compile_Time_Known_Value (High)
722 or else Etype (Index) = Any_Type
723 then
724 return False;
725
726 else
727 Dim := Expr_Value (High) - Expr_Value (Low) + 1;
728
729 if Dim >= 0 then
730 Esiz := Esiz * Dim;
731 else
732 Esiz := Uint_0;
733 end if;
734 end if;
735
736 Next_Index (Index);
737 end loop;
738
739 Set_Small_Size (T, Esiz);
740 return True;
741 end;
742
743 -- Access types always have known at compile time sizes
744
745 elsif Is_Access_Type (T) then
746 return True;
747
748 -- For non-generic private types, go to underlying type if present
749
750 elsif Is_Private_Type (T)
751 and then not Is_Generic_Type (T)
752 and then Present (Underlying_Type (T))
753 then
754 -- Don't do any recursion on type with error posted, since we may
755 -- have a malformed type that leads us into a loop.
756
757 if Error_Posted (T) then
758 return False;
759 else
760 return Size_Known (Underlying_Type (T));
761 end if;
762
763 -- Record types
764
765 elsif Is_Record_Type (T) then
766
767 -- A class-wide type is never considered to have a known size
768
769 if Is_Class_Wide_Type (T) then
770 return False;
771
772 -- A subtype of a variant record must not have non-static
773 -- discriminated components.
774
775 elsif T /= Base_Type (T)
776 and then not Static_Discriminated_Components (T)
777 then
778 return False;
779
780 -- Don't do any recursion on type with error posted, since we may
781 -- have a malformed type that leads us into a loop.
782
783 elsif Error_Posted (T) then
784 return False;
785 end if;
786
787 -- Now look at the components of the record
788
789 declare
790 -- The following two variables are used to keep track of the
791 -- size of packed records if we can tell the size of the packed
792 -- record in the front end. Packed_Size_Known is True if so far
793 -- we can figure out the size. It is initialized to True for a
794 -- packed record, unless the record has discriminants. The
795 -- reason we eliminate the discriminated case is that we don't
796 -- know the way the back end lays out discriminated packed
797 -- records. If Packed_Size_Known is True, then Packed_Size is
798 -- the size in bits so far.
799
800 Packed_Size_Known : Boolean :=
801 Is_Packed (T)
802 and then not Has_Discriminants (T);
803
804 Packed_Size : Uint := Uint_0;
805
806 begin
807 -- Test for variant part present
808
809 if Has_Discriminants (T)
810 and then Present (Parent (T))
811 and then Nkind (Parent (T)) = N_Full_Type_Declaration
812 and then Nkind (Type_Definition (Parent (T))) =
813 N_Record_Definition
814 and then not Null_Present (Type_Definition (Parent (T)))
815 and then Present (Variant_Part
816 (Component_List (Type_Definition (Parent (T)))))
817 then
818 -- If variant part is present, and type is unconstrained,
819 -- then we must have defaulted discriminants, or a size
820 -- clause must be present for the type, or else the size
821 -- is definitely not known at compile time.
822
823 if not Is_Constrained (T)
824 and then
825 No (Discriminant_Default_Value (First_Discriminant (T)))
826 and then Unknown_RM_Size (T)
827 then
828 return False;
829 end if;
830 end if;
831
832 -- Loop through components
833
834 Comp := First_Component_Or_Discriminant (T);
835 while Present (Comp) loop
836 Ctyp := Etype (Comp);
837
838 -- We do not know the packed size if there is a component
839 -- clause present (we possibly could, but this would only
840 -- help in the case of a record with partial rep clauses.
841 -- That's because in the case of full rep clauses, the
842 -- size gets figured out anyway by a different circuit).
843
844 if Present (Component_Clause (Comp)) then
845 Packed_Size_Known := False;
846 end if;
847
848 -- We need to identify a component that is an array where
849 -- the index type is an enumeration type with non-standard
850 -- representation, and some bound of the type depends on a
851 -- discriminant.
852
853 -- This is because gigi computes the size by doing a
854 -- substitution of the appropriate discriminant value in
855 -- the size expression for the base type, and gigi is not
856 -- clever enough to evaluate the resulting expression (which
857 -- involves a call to rep_to_pos) at compile time.
858
859 -- It would be nice if gigi would either recognize that
860 -- this expression can be computed at compile time, or
861 -- alternatively figured out the size from the subtype
862 -- directly, where all the information is at hand ???
863
864 if Is_Array_Type (Etype (Comp))
865 and then Present (Packed_Array_Type (Etype (Comp)))
866 then
867 declare
868 Ocomp : constant Entity_Id :=
869 Original_Record_Component (Comp);
870 OCtyp : constant Entity_Id := Etype (Ocomp);
871 Ind : Node_Id;
872 Indtyp : Entity_Id;
873 Lo, Hi : Node_Id;
874
875 begin
876 Ind := First_Index (OCtyp);
877 while Present (Ind) loop
878 Indtyp := Etype (Ind);
879
880 if Is_Enumeration_Type (Indtyp)
881 and then Has_Non_Standard_Rep (Indtyp)
882 then
883 Lo := Type_Low_Bound (Indtyp);
884 Hi := Type_High_Bound (Indtyp);
885
886 if Is_Entity_Name (Lo)
887 and then Ekind (Entity (Lo)) = E_Discriminant
888 then
889 return False;
890
891 elsif Is_Entity_Name (Hi)
892 and then Ekind (Entity (Hi)) = E_Discriminant
893 then
894 return False;
895 end if;
896 end if;
897
898 Next_Index (Ind);
899 end loop;
900 end;
901 end if;
902
903 -- Clearly size of record is not known if the size of one of
904 -- the components is not known.
905
906 if not Size_Known (Ctyp) then
907 return False;
908 end if;
909
910 -- Accumulate packed size if possible
911
912 if Packed_Size_Known then
913
914 -- We can only deal with elementary types, since for
915 -- non-elementary components, alignment enters into the
916 -- picture, and we don't know enough to handle proper
917 -- alignment in this context. Packed arrays count as
918 -- elementary if the representation is a modular type.
919
920 if Is_Elementary_Type (Ctyp)
921 or else (Is_Array_Type (Ctyp)
922 and then Present (Packed_Array_Type (Ctyp))
923 and then Is_Modular_Integer_Type
924 (Packed_Array_Type (Ctyp)))
925 then
926 -- If RM_Size is known and static, then we can keep
927 -- accumulating the packed size.
928
929 if Known_Static_RM_Size (Ctyp) then
930
931 -- A little glitch, to be removed sometime ???
932 -- gigi does not understand zero sizes yet.
933
934 if RM_Size (Ctyp) = Uint_0 then
935 Packed_Size_Known := False;
936
937 -- Normal case where we can keep accumulating the
938 -- packed array size.
939
940 else
941 Packed_Size := Packed_Size + RM_Size (Ctyp);
942 end if;
943
944 -- If we have a field whose RM_Size is not known then
945 -- we can't figure out the packed size here.
946
947 else
948 Packed_Size_Known := False;
949 end if;
950
951 -- If we have a non-elementary type we can't figure out
952 -- the packed array size (alignment issues).
953
954 else
955 Packed_Size_Known := False;
956 end if;
957 end if;
958
959 Next_Component_Or_Discriminant (Comp);
960 end loop;
961
962 if Packed_Size_Known then
963 Set_Small_Size (T, Packed_Size);
964 end if;
965
966 return True;
967 end;
968
969 -- All other cases, size not known at compile time
970
971 else
972 return False;
973 end if;
974 end Size_Known;
975
976 -------------------------------------
977 -- Static_Discriminated_Components --
978 -------------------------------------
979
980 function Static_Discriminated_Components
981 (T : Entity_Id) return Boolean
982 is
983 Constraint : Elmt_Id;
984
985 begin
986 if Has_Discriminants (T)
987 and then Present (Discriminant_Constraint (T))
988 and then Present (First_Component (T))
989 then
990 Constraint := First_Elmt (Discriminant_Constraint (T));
991 while Present (Constraint) loop
992 if not Compile_Time_Known_Value (Node (Constraint)) then
993 return False;
994 end if;
995
996 Next_Elmt (Constraint);
997 end loop;
998 end if;
999
1000 return True;
1001 end Static_Discriminated_Components;
1002
1003 -- Start of processing for Check_Compile_Time_Size
1004
1005 begin
1006 Set_Size_Known_At_Compile_Time (T, Size_Known (T));
1007 end Check_Compile_Time_Size;
1008
1009 -----------------------------
1010 -- Check_Debug_Info_Needed --
1011 -----------------------------
1012
1013 procedure Check_Debug_Info_Needed (T : Entity_Id) is
1014 begin
1015 if Debug_Info_Off (T) then
1016 return;
1017
1018 elsif Comes_From_Source (T)
1019 or else Debug_Generated_Code
1020 or else Debug_Flag_VV
1021 or else Needs_Debug_Info (T)
1022 then
1023 Set_Debug_Info_Needed (T);
1024 end if;
1025 end Check_Debug_Info_Needed;
1026
1027 ----------------------------
1028 -- Check_Strict_Alignment --
1029 ----------------------------
1030
1031 procedure Check_Strict_Alignment (E : Entity_Id) is
1032 Comp : Entity_Id;
1033
1034 begin
1035 if Is_Tagged_Type (E) or else Is_Concurrent_Type (E) then
1036 Set_Strict_Alignment (E);
1037
1038 elsif Is_Array_Type (E) then
1039 Set_Strict_Alignment (E, Strict_Alignment (Component_Type (E)));
1040
1041 elsif Is_Record_Type (E) then
1042 if Is_Limited_Record (E) then
1043 Set_Strict_Alignment (E);
1044 return;
1045 end if;
1046
1047 Comp := First_Component (E);
1048 while Present (Comp) loop
1049 if not Is_Type (Comp)
1050 and then (Strict_Alignment (Etype (Comp))
1051 or else Is_Aliased (Comp))
1052 then
1053 Set_Strict_Alignment (E);
1054 return;
1055 end if;
1056
1057 Next_Component (Comp);
1058 end loop;
1059 end if;
1060 end Check_Strict_Alignment;
1061
1062 -------------------------
1063 -- Check_Unsigned_Type --
1064 -------------------------
1065
1066 procedure Check_Unsigned_Type (E : Entity_Id) is
1067 Ancestor : Entity_Id;
1068 Lo_Bound : Node_Id;
1069 Btyp : Entity_Id;
1070
1071 begin
1072 if not Is_Discrete_Or_Fixed_Point_Type (E) then
1073 return;
1074 end if;
1075
1076 -- Do not attempt to analyze case where range was in error
1077
1078 if No (Scalar_Range (E))
1079 or else Error_Posted (Scalar_Range (E))
1080 then
1081 return;
1082 end if;
1083
1084 -- The situation that is non trivial is something like
1085
1086 -- subtype x1 is integer range -10 .. +10;
1087 -- subtype x2 is x1 range 0 .. V1;
1088 -- subtype x3 is x2 range V2 .. V3;
1089 -- subtype x4 is x3 range V4 .. V5;
1090
1091 -- where Vn are variables. Here the base type is signed, but we still
1092 -- know that x4 is unsigned because of the lower bound of x2.
1093
1094 -- The only way to deal with this is to look up the ancestor chain
1095
1096 Ancestor := E;
1097 loop
1098 if Ancestor = Any_Type or else Etype (Ancestor) = Any_Type then
1099 return;
1100 end if;
1101
1102 Lo_Bound := Type_Low_Bound (Ancestor);
1103
1104 if Compile_Time_Known_Value (Lo_Bound) then
1105
1106 if Expr_Rep_Value (Lo_Bound) >= 0 then
1107 Set_Is_Unsigned_Type (E, True);
1108 end if;
1109
1110 return;
1111
1112 else
1113 Ancestor := Ancestor_Subtype (Ancestor);
1114
1115 -- If no ancestor had a static lower bound, go to base type
1116
1117 if No (Ancestor) then
1118
1119 -- Note: the reason we still check for a compile time known
1120 -- value for the base type is that at least in the case of
1121 -- generic formals, we can have bounds that fail this test,
1122 -- and there may be other cases in error situations.
1123
1124 Btyp := Base_Type (E);
1125
1126 if Btyp = Any_Type or else Etype (Btyp) = Any_Type then
1127 return;
1128 end if;
1129
1130 Lo_Bound := Type_Low_Bound (Base_Type (E));
1131
1132 if Compile_Time_Known_Value (Lo_Bound)
1133 and then Expr_Rep_Value (Lo_Bound) >= 0
1134 then
1135 Set_Is_Unsigned_Type (E, True);
1136 end if;
1137
1138 return;
1139 end if;
1140 end if;
1141 end loop;
1142 end Check_Unsigned_Type;
1143
1144 -------------------------
1145 -- Is_Atomic_Aggregate --
1146 -------------------------
1147
1148 function Is_Atomic_Aggregate
1149 (E : Entity_Id;
1150 Typ : Entity_Id) return Boolean
1151 is
1152 Loc : constant Source_Ptr := Sloc (E);
1153 New_N : Node_Id;
1154 Par : Node_Id;
1155 Temp : Entity_Id;
1156
1157 begin
1158 Par := Parent (E);
1159
1160 -- Array may be qualified, so find outer context
1161
1162 if Nkind (Par) = N_Qualified_Expression then
1163 Par := Parent (Par);
1164 end if;
1165
1166 if Nkind_In (Par, N_Object_Declaration, N_Assignment_Statement)
1167 and then Comes_From_Source (Par)
1168 then
1169 Temp := Make_Temporary (Loc, 'T', E);
1170 New_N :=
1171 Make_Object_Declaration (Loc,
1172 Defining_Identifier => Temp,
1173 Object_Definition => New_Occurrence_Of (Typ, Loc),
1174 Expression => Relocate_Node (E));
1175 Insert_Before (Par, New_N);
1176 Analyze (New_N);
1177
1178 Set_Expression (Par, New_Occurrence_Of (Temp, Loc));
1179 return True;
1180
1181 else
1182 return False;
1183 end if;
1184 end Is_Atomic_Aggregate;
1185
1186 ----------------
1187 -- Freeze_All --
1188 ----------------
1189
1190 -- Note: the easy coding for this procedure would be to just build a
1191 -- single list of freeze nodes and then insert them and analyze them
1192 -- all at once. This won't work, because the analysis of earlier freeze
1193 -- nodes may recursively freeze types which would otherwise appear later
1194 -- on in the freeze list. So we must analyze and expand the freeze nodes
1195 -- as they are generated.
1196
1197 procedure Freeze_All (From : Entity_Id; After : in out Node_Id) is
1198 E : Entity_Id;
1199 Decl : Node_Id;
1200
1201 procedure Freeze_All_Ent (From : Entity_Id; After : in out Node_Id);
1202 -- This is the internal recursive routine that does freezing of entities
1203 -- (but NOT the analysis of default expressions, which should not be
1204 -- recursive, we don't want to analyze those till we are sure that ALL
1205 -- the types are frozen).
1206
1207 --------------------
1208 -- Freeze_All_Ent --
1209 --------------------
1210
1211 procedure Freeze_All_Ent (From : Entity_Id; After : in out Node_Id) is
1212 E : Entity_Id;
1213 Flist : List_Id;
1214 Lastn : Node_Id;
1215
1216 procedure Process_Flist;
1217 -- If freeze nodes are present, insert and analyze, and reset cursor
1218 -- for next insertion.
1219
1220 -------------------
1221 -- Process_Flist --
1222 -------------------
1223
1224 procedure Process_Flist is
1225 begin
1226 if Is_Non_Empty_List (Flist) then
1227 Lastn := Next (After);
1228 Insert_List_After_And_Analyze (After, Flist);
1229
1230 if Present (Lastn) then
1231 After := Prev (Lastn);
1232 else
1233 After := Last (List_Containing (After));
1234 end if;
1235 end if;
1236 end Process_Flist;
1237
1238 -- Start or processing for Freeze_All_Ent
1239
1240 begin
1241 E := From;
1242 while Present (E) loop
1243
1244 -- If the entity is an inner package which is not a package
1245 -- renaming, then its entities must be frozen at this point. Note
1246 -- that such entities do NOT get frozen at the end of the nested
1247 -- package itself (only library packages freeze).
1248
1249 -- Same is true for task declarations, where anonymous records
1250 -- created for entry parameters must be frozen.
1251
1252 if Ekind (E) = E_Package
1253 and then No (Renamed_Object (E))
1254 and then not Is_Child_Unit (E)
1255 and then not Is_Frozen (E)
1256 then
1257 Push_Scope (E);
1258 Install_Visible_Declarations (E);
1259 Install_Private_Declarations (E);
1260
1261 Freeze_All (First_Entity (E), After);
1262
1263 End_Package_Scope (E);
1264
1265 if Is_Generic_Instance (E)
1266 and then Has_Delayed_Freeze (E)
1267 then
1268 Set_Has_Delayed_Freeze (E, False);
1269 Expand_N_Package_Declaration (Unit_Declaration_Node (E));
1270 end if;
1271
1272 elsif Ekind (E) in Task_Kind
1273 and then
1274 (Nkind (Parent (E)) = N_Task_Type_Declaration
1275 or else
1276 Nkind (Parent (E)) = N_Single_Task_Declaration)
1277 then
1278 Push_Scope (E);
1279 Freeze_All (First_Entity (E), After);
1280 End_Scope;
1281
1282 -- For a derived tagged type, we must ensure that all the
1283 -- primitive operations of the parent have been frozen, so that
1284 -- their addresses will be in the parent's dispatch table at the
1285 -- point it is inherited.
1286
1287 elsif Ekind (E) = E_Record_Type
1288 and then Is_Tagged_Type (E)
1289 and then Is_Tagged_Type (Etype (E))
1290 and then Is_Derived_Type (E)
1291 then
1292 declare
1293 Prim_List : constant Elist_Id :=
1294 Primitive_Operations (Etype (E));
1295
1296 Prim : Elmt_Id;
1297 Subp : Entity_Id;
1298
1299 begin
1300 Prim := First_Elmt (Prim_List);
1301 while Present (Prim) loop
1302 Subp := Node (Prim);
1303
1304 if Comes_From_Source (Subp)
1305 and then not Is_Frozen (Subp)
1306 then
1307 Flist := Freeze_Entity (Subp, After);
1308 Process_Flist;
1309 end if;
1310
1311 Next_Elmt (Prim);
1312 end loop;
1313 end;
1314 end if;
1315
1316 if not Is_Frozen (E) then
1317 Flist := Freeze_Entity (E, After);
1318 Process_Flist;
1319
1320 -- If already frozen, and there are delayed aspects, this is where
1321 -- we do the visibility check for these aspects (see Sem_Ch13 spec
1322 -- for a description of how we handle aspect visibility).
1323
1324 elsif Has_Delayed_Aspects (E) then
1325 declare
1326 Ritem : Node_Id;
1327
1328 begin
1329 Ritem := First_Rep_Item (E);
1330 while Present (Ritem) loop
1331 if Nkind (Ritem) = N_Aspect_Specification
1332 and then Entity (Ritem) = E
1333 and then Is_Delayed_Aspect (Ritem)
1334 then
1335 Check_Aspect_At_End_Of_Declarations (Ritem);
1336 end if;
1337
1338 Ritem := Next_Rep_Item (Ritem);
1339 end loop;
1340 end;
1341 end if;
1342
1343 -- If an incomplete type is still not frozen, this may be a
1344 -- premature freezing because of a body declaration that follows.
1345 -- Indicate where the freezing took place.
1346
1347 -- If the freezing is caused by the end of the current declarative
1348 -- part, it is a Taft Amendment type, and there is no error.
1349
1350 if not Is_Frozen (E)
1351 and then Ekind (E) = E_Incomplete_Type
1352 then
1353 declare
1354 Bod : constant Node_Id := Next (After);
1355
1356 begin
1357 if (Nkind_In (Bod, N_Subprogram_Body,
1358 N_Entry_Body,
1359 N_Package_Body,
1360 N_Protected_Body,
1361 N_Task_Body)
1362 or else Nkind (Bod) in N_Body_Stub)
1363 and then
1364 List_Containing (After) = List_Containing (Parent (E))
1365 then
1366 Error_Msg_Sloc := Sloc (Next (After));
1367 Error_Msg_NE
1368 ("type& is frozen# before its full declaration",
1369 Parent (E), E);
1370 end if;
1371 end;
1372 end if;
1373
1374 Next_Entity (E);
1375 end loop;
1376 end Freeze_All_Ent;
1377
1378 -- Start of processing for Freeze_All
1379
1380 begin
1381 Freeze_All_Ent (From, After);
1382
1383 -- Now that all types are frozen, we can deal with default expressions
1384 -- that require us to build a default expression functions. This is the
1385 -- point at which such functions are constructed (after all types that
1386 -- might be used in such expressions have been frozen).
1387
1388 -- For subprograms that are renaming_as_body, we create the wrapper
1389 -- bodies as needed.
1390
1391 -- We also add finalization chains to access types whose designated
1392 -- types are controlled. This is normally done when freezing the type,
1393 -- but this misses recursive type definitions where the later members
1394 -- of the recursion introduce controlled components.
1395
1396 -- Loop through entities
1397
1398 E := From;
1399 while Present (E) loop
1400 if Is_Subprogram (E) then
1401
1402 if not Default_Expressions_Processed (E) then
1403 Process_Default_Expressions (E, After);
1404 end if;
1405
1406 if not Has_Completion (E) then
1407 Decl := Unit_Declaration_Node (E);
1408
1409 if Nkind (Decl) = N_Subprogram_Renaming_Declaration then
1410 Build_And_Analyze_Renamed_Body (Decl, E, After);
1411
1412 elsif Nkind (Decl) = N_Subprogram_Declaration
1413 and then Present (Corresponding_Body (Decl))
1414 and then
1415 Nkind (Unit_Declaration_Node (Corresponding_Body (Decl)))
1416 = N_Subprogram_Renaming_Declaration
1417 then
1418 Build_And_Analyze_Renamed_Body
1419 (Decl, Corresponding_Body (Decl), After);
1420 end if;
1421 end if;
1422
1423 elsif Ekind (E) in Task_Kind
1424 and then
1425 (Nkind (Parent (E)) = N_Task_Type_Declaration
1426 or else
1427 Nkind (Parent (E)) = N_Single_Task_Declaration)
1428 then
1429 declare
1430 Ent : Entity_Id;
1431
1432 begin
1433 Ent := First_Entity (E);
1434 while Present (Ent) loop
1435 if Is_Entry (Ent)
1436 and then not Default_Expressions_Processed (Ent)
1437 then
1438 Process_Default_Expressions (Ent, After);
1439 end if;
1440
1441 Next_Entity (Ent);
1442 end loop;
1443 end;
1444
1445 -- We add finalization masters to access types whose designated types
1446 -- require finalization. This is normally done when freezing the
1447 -- type, but this misses recursive type definitions where the later
1448 -- members of the recursion introduce controlled components (such as
1449 -- can happen when incomplete types are involved), as well cases
1450 -- where a component type is private and the controlled full type
1451 -- occurs after the access type is frozen. Cases that don't need a
1452 -- finalization master are generic formal types (the actual type will
1453 -- have it) and types with Java and CIL conventions, since those are
1454 -- used for API bindings. (Are there any other cases that should be
1455 -- excluded here???)
1456
1457 elsif Is_Access_Type (E)
1458 and then Comes_From_Source (E)
1459 and then not Is_Generic_Type (E)
1460 and then Needs_Finalization (Designated_Type (E))
1461 then
1462 Build_Finalization_Master (E);
1463 end if;
1464
1465 Next_Entity (E);
1466 end loop;
1467 end Freeze_All;
1468
1469 -----------------------
1470 -- Freeze_And_Append --
1471 -----------------------
1472
1473 procedure Freeze_And_Append
1474 (Ent : Entity_Id;
1475 N : Node_Id;
1476 Result : in out List_Id)
1477 is
1478 L : constant List_Id := Freeze_Entity (Ent, N);
1479 begin
1480 if Is_Non_Empty_List (L) then
1481 if Result = No_List then
1482 Result := L;
1483 else
1484 Append_List (L, Result);
1485 end if;
1486 end if;
1487 end Freeze_And_Append;
1488
1489 -------------------
1490 -- Freeze_Before --
1491 -------------------
1492
1493 procedure Freeze_Before (N : Node_Id; T : Entity_Id) is
1494 Freeze_Nodes : constant List_Id := Freeze_Entity (T, N);
1495 begin
1496 if Is_Non_Empty_List (Freeze_Nodes) then
1497 Insert_Actions (N, Freeze_Nodes);
1498 end if;
1499 end Freeze_Before;
1500
1501 -------------------
1502 -- Freeze_Entity --
1503 -------------------
1504
1505 function Freeze_Entity (E : Entity_Id; N : Node_Id) return List_Id is
1506 Loc : constant Source_Ptr := Sloc (N);
1507 Test_E : Entity_Id := E;
1508 Comp : Entity_Id;
1509 F_Node : Node_Id;
1510 Indx : Node_Id;
1511 Formal : Entity_Id;
1512 Atype : Entity_Id;
1513
1514 Result : List_Id := No_List;
1515 -- List of freezing actions, left at No_List if none
1516
1517 Has_Default_Initialization : Boolean := False;
1518 -- This flag gets set to true for a variable with default initialization
1519
1520 procedure Add_To_Result (N : Node_Id);
1521 -- N is a freezing action to be appended to the Result
1522
1523 procedure Check_Current_Instance (Comp_Decl : Node_Id);
1524 -- Check that an Access or Unchecked_Access attribute with a prefix
1525 -- which is the current instance type can only be applied when the type
1526 -- is limited.
1527
1528 procedure Check_Suspicious_Modulus (Utype : Entity_Id);
1529 -- Give warning for modulus of 8, 16, 32, or 64 given as an explicit
1530 -- integer literal without an explicit corresponding size clause. The
1531 -- caller has checked that Utype is a modular integer type.
1532
1533 function After_Last_Declaration return Boolean;
1534 -- If Loc is a freeze_entity that appears after the last declaration
1535 -- in the scope, inhibit error messages on late completion.
1536
1537 procedure Freeze_Record_Type (Rec : Entity_Id);
1538 -- Freeze each component, handle some representation clauses, and freeze
1539 -- primitive operations if this is a tagged type.
1540
1541 -------------------
1542 -- Add_To_Result --
1543 -------------------
1544
1545 procedure Add_To_Result (N : Node_Id) is
1546 begin
1547 if No (Result) then
1548 Result := New_List (N);
1549 else
1550 Append (N, Result);
1551 end if;
1552 end Add_To_Result;
1553
1554 ----------------------------
1555 -- After_Last_Declaration --
1556 ----------------------------
1557
1558 function After_Last_Declaration return Boolean is
1559 Spec : constant Node_Id := Parent (Current_Scope);
1560 begin
1561 if Nkind (Spec) = N_Package_Specification then
1562 if Present (Private_Declarations (Spec)) then
1563 return Loc >= Sloc (Last (Private_Declarations (Spec)));
1564 elsif Present (Visible_Declarations (Spec)) then
1565 return Loc >= Sloc (Last (Visible_Declarations (Spec)));
1566 else
1567 return False;
1568 end if;
1569 else
1570 return False;
1571 end if;
1572 end After_Last_Declaration;
1573
1574 ----------------------------
1575 -- Check_Current_Instance --
1576 ----------------------------
1577
1578 procedure Check_Current_Instance (Comp_Decl : Node_Id) is
1579
1580 Rec_Type : constant Entity_Id :=
1581 Scope (Defining_Identifier (Comp_Decl));
1582
1583 Decl : constant Node_Id := Parent (Rec_Type);
1584
1585 function Process (N : Node_Id) return Traverse_Result;
1586 -- Process routine to apply check to given node
1587
1588 -------------
1589 -- Process --
1590 -------------
1591
1592 function Process (N : Node_Id) return Traverse_Result is
1593 begin
1594 case Nkind (N) is
1595 when N_Attribute_Reference =>
1596 if (Attribute_Name (N) = Name_Access
1597 or else
1598 Attribute_Name (N) = Name_Unchecked_Access)
1599 and then Is_Entity_Name (Prefix (N))
1600 and then Is_Type (Entity (Prefix (N)))
1601 and then Entity (Prefix (N)) = E
1602 then
1603 Error_Msg_N
1604 ("current instance must be a limited type", Prefix (N));
1605 return Abandon;
1606 else
1607 return OK;
1608 end if;
1609
1610 when others => return OK;
1611 end case;
1612 end Process;
1613
1614 procedure Traverse is new Traverse_Proc (Process);
1615
1616 -- Start of processing for Check_Current_Instance
1617
1618 begin
1619 -- In Ada 95, the (imprecise) rule is that the current instance of a
1620 -- limited type is aliased. In Ada 2005, limitedness must be
1621 -- explicit: either a tagged type, or a limited record.
1622
1623 if Is_Limited_Type (Rec_Type)
1624 and then (Ada_Version < Ada_2005 or else Is_Tagged_Type (Rec_Type))
1625 then
1626 return;
1627
1628 elsif Nkind (Decl) = N_Full_Type_Declaration
1629 and then Limited_Present (Type_Definition (Decl))
1630 then
1631 return;
1632
1633 else
1634 Traverse (Comp_Decl);
1635 end if;
1636 end Check_Current_Instance;
1637
1638 ------------------------------
1639 -- Check_Suspicious_Modulus --
1640 ------------------------------
1641
1642 procedure Check_Suspicious_Modulus (Utype : Entity_Id) is
1643 Decl : constant Node_Id := Declaration_Node (Underlying_Type (Utype));
1644
1645 begin
1646 if Nkind (Decl) = N_Full_Type_Declaration then
1647 declare
1648 Tdef : constant Node_Id := Type_Definition (Decl);
1649 begin
1650 if Nkind (Tdef) = N_Modular_Type_Definition then
1651 declare
1652 Modulus : constant Node_Id :=
1653 Original_Node (Expression (Tdef));
1654 begin
1655 if Nkind (Modulus) = N_Integer_Literal then
1656 declare
1657 Modv : constant Uint := Intval (Modulus);
1658 Sizv : constant Uint := RM_Size (Utype);
1659
1660 begin
1661 -- First case, modulus and size are the same. This
1662 -- happens if you have something like mod 32, with
1663 -- an explicit size of 32, this is for sure a case
1664 -- where the warning is given, since it is seems
1665 -- very unlikely that someone would want e.g. a
1666 -- five bit type stored in 32 bits. It is much
1667 -- more likely they wanted a 32-bit type.
1668
1669 if Modv = Sizv then
1670 null;
1671
1672 -- Second case, the modulus is 32 or 64 and no
1673 -- size clause is present. This is a less clear
1674 -- case for giving the warning, but in the case
1675 -- of 32/64 (5-bit or 6-bit types) these seem rare
1676 -- enough that it is a likely error (and in any
1677 -- case using 2**5 or 2**6 in these cases seems
1678 -- clearer. We don't include 8 or 16 here, simply
1679 -- because in practice 3-bit and 4-bit types are
1680 -- more common and too many false positives if
1681 -- we warn in these cases.
1682
1683 elsif not Has_Size_Clause (Utype)
1684 and then (Modv = Uint_32 or else Modv = Uint_64)
1685 then
1686 null;
1687
1688 -- No warning needed
1689
1690 else
1691 return;
1692 end if;
1693
1694 -- If we fall through, give warning
1695
1696 Error_Msg_Uint_1 := Modv;
1697 Error_Msg_N
1698 ("?2 '*'*^' may have been intended here",
1699 Modulus);
1700 end;
1701 end if;
1702 end;
1703 end if;
1704 end;
1705 end if;
1706 end Check_Suspicious_Modulus;
1707
1708 ------------------------
1709 -- Freeze_Record_Type --
1710 ------------------------
1711
1712 procedure Freeze_Record_Type (Rec : Entity_Id) is
1713 Comp : Entity_Id;
1714 IR : Node_Id;
1715 ADC : Node_Id;
1716 Prev : Entity_Id;
1717
1718 Junk : Boolean;
1719 pragma Warnings (Off, Junk);
1720
1721 Unplaced_Component : Boolean := False;
1722 -- Set True if we find at least one component with no component
1723 -- clause (used to warn about useless Pack pragmas).
1724
1725 Placed_Component : Boolean := False;
1726 -- Set True if we find at least one component with a component
1727 -- clause (used to warn about useless Bit_Order pragmas, and also
1728 -- to detect cases where Implicit_Packing may have an effect).
1729
1730 All_Scalar_Components : Boolean := True;
1731 -- Set False if we encounter a component of a non-scalar type
1732
1733 Scalar_Component_Total_RM_Size : Uint := Uint_0;
1734 Scalar_Component_Total_Esize : Uint := Uint_0;
1735 -- Accumulates total RM_Size values and total Esize values of all
1736 -- scalar components. Used for processing of Implicit_Packing.
1737
1738 function Check_Allocator (N : Node_Id) return Node_Id;
1739 -- If N is an allocator, possibly wrapped in one or more level of
1740 -- qualified expression(s), return the inner allocator node, else
1741 -- return Empty.
1742
1743 procedure Check_Itype (Typ : Entity_Id);
1744 -- If the component subtype is an access to a constrained subtype of
1745 -- an already frozen type, make the subtype frozen as well. It might
1746 -- otherwise be frozen in the wrong scope, and a freeze node on
1747 -- subtype has no effect. Similarly, if the component subtype is a
1748 -- regular (not protected) access to subprogram, set the anonymous
1749 -- subprogram type to frozen as well, to prevent an out-of-scope
1750 -- freeze node at some eventual point of call. Protected operations
1751 -- are handled elsewhere.
1752
1753 ---------------------
1754 -- Check_Allocator --
1755 ---------------------
1756
1757 function Check_Allocator (N : Node_Id) return Node_Id is
1758 Inner : Node_Id;
1759 begin
1760 Inner := N;
1761 loop
1762 if Nkind (Inner) = N_Allocator then
1763 return Inner;
1764 elsif Nkind (Inner) = N_Qualified_Expression then
1765 Inner := Expression (Inner);
1766 else
1767 return Empty;
1768 end if;
1769 end loop;
1770 end Check_Allocator;
1771
1772 -----------------
1773 -- Check_Itype --
1774 -----------------
1775
1776 procedure Check_Itype (Typ : Entity_Id) is
1777 Desig : constant Entity_Id := Designated_Type (Typ);
1778
1779 begin
1780 if not Is_Frozen (Desig)
1781 and then Is_Frozen (Base_Type (Desig))
1782 then
1783 Set_Is_Frozen (Desig);
1784
1785 -- In addition, add an Itype_Reference to ensure that the
1786 -- access subtype is elaborated early enough. This cannot be
1787 -- done if the subtype may depend on discriminants.
1788
1789 if Ekind (Comp) = E_Component
1790 and then Is_Itype (Etype (Comp))
1791 and then not Has_Discriminants (Rec)
1792 then
1793 IR := Make_Itype_Reference (Sloc (Comp));
1794 Set_Itype (IR, Desig);
1795 Add_To_Result (IR);
1796 end if;
1797
1798 elsif Ekind (Typ) = E_Anonymous_Access_Subprogram_Type
1799 and then Convention (Desig) /= Convention_Protected
1800 then
1801 Set_Is_Frozen (Desig);
1802 end if;
1803 end Check_Itype;
1804
1805 -- Start of processing for Freeze_Record_Type
1806
1807 begin
1808 -- Freeze components and embedded subtypes
1809
1810 Comp := First_Entity (Rec);
1811 Prev := Empty;
1812 while Present (Comp) loop
1813
1814 -- First handle the component case
1815
1816 if Ekind (Comp) = E_Component
1817 or else Ekind (Comp) = E_Discriminant
1818 then
1819 declare
1820 CC : constant Node_Id := Component_Clause (Comp);
1821
1822 begin
1823 -- Freezing a record type freezes the type of each of its
1824 -- components. However, if the type of the component is
1825 -- part of this record, we do not want or need a separate
1826 -- Freeze_Node. Note that Is_Itype is wrong because that's
1827 -- also set in private type cases. We also can't check for
1828 -- the Scope being exactly Rec because of private types and
1829 -- record extensions.
1830
1831 if Is_Itype (Etype (Comp))
1832 and then Is_Record_Type (Underlying_Type
1833 (Scope (Etype (Comp))))
1834 then
1835 Undelay_Type (Etype (Comp));
1836 end if;
1837
1838 Freeze_And_Append (Etype (Comp), N, Result);
1839
1840 -- Check for error of component clause given for variable
1841 -- sized type. We have to delay this test till this point,
1842 -- since the component type has to be frozen for us to know
1843 -- if it is variable length. We omit this test in a generic
1844 -- context, it will be applied at instantiation time.
1845
1846 -- We also omit this test in CodePeer mode, since we do not
1847 -- have sufficient info on size and representation clauses.
1848
1849 if Present (CC) then
1850 Placed_Component := True;
1851
1852 if Inside_A_Generic then
1853 null;
1854
1855 elsif CodePeer_Mode then
1856 null;
1857
1858 elsif not
1859 Size_Known_At_Compile_Time
1860 (Underlying_Type (Etype (Comp)))
1861 then
1862 Error_Msg_N
1863 ("component clause not allowed for variable " &
1864 "length component", CC);
1865 end if;
1866
1867 else
1868 Unplaced_Component := True;
1869 end if;
1870
1871 -- Case of component requires byte alignment
1872
1873 if Must_Be_On_Byte_Boundary (Etype (Comp)) then
1874
1875 -- Set the enclosing record to also require byte align
1876
1877 Set_Must_Be_On_Byte_Boundary (Rec);
1878
1879 -- Check for component clause that is inconsistent with
1880 -- the required byte boundary alignment.
1881
1882 if Present (CC)
1883 and then Normalized_First_Bit (Comp) mod
1884 System_Storage_Unit /= 0
1885 then
1886 Error_Msg_N
1887 ("component & must be byte aligned",
1888 Component_Name (Component_Clause (Comp)));
1889 end if;
1890 end if;
1891 end;
1892 end if;
1893
1894 -- Gather data for possible Implicit_Packing later. Note that at
1895 -- this stage we might be dealing with a real component, or with
1896 -- an implicit subtype declaration.
1897
1898 if not Is_Scalar_Type (Etype (Comp)) then
1899 All_Scalar_Components := False;
1900 else
1901 Scalar_Component_Total_RM_Size :=
1902 Scalar_Component_Total_RM_Size + RM_Size (Etype (Comp));
1903 Scalar_Component_Total_Esize :=
1904 Scalar_Component_Total_Esize + Esize (Etype (Comp));
1905 end if;
1906
1907 -- If the component is an Itype with Delayed_Freeze and is either
1908 -- a record or array subtype and its base type has not yet been
1909 -- frozen, we must remove this from the entity list of this record
1910 -- and put it on the entity list of the scope of its base type.
1911 -- Note that we know that this is not the type of a component
1912 -- since we cleared Has_Delayed_Freeze for it in the previous
1913 -- loop. Thus this must be the Designated_Type of an access type,
1914 -- which is the type of a component.
1915
1916 if Is_Itype (Comp)
1917 and then Is_Type (Scope (Comp))
1918 and then Is_Composite_Type (Comp)
1919 and then Base_Type (Comp) /= Comp
1920 and then Has_Delayed_Freeze (Comp)
1921 and then not Is_Frozen (Base_Type (Comp))
1922 then
1923 declare
1924 Will_Be_Frozen : Boolean := False;
1925 S : Entity_Id;
1926
1927 begin
1928 -- We have a pretty bad kludge here. Suppose Rec is subtype
1929 -- being defined in a subprogram that's created as part of
1930 -- the freezing of Rec'Base. In that case, we know that
1931 -- Comp'Base must have already been frozen by the time we
1932 -- get to elaborate this because Gigi doesn't elaborate any
1933 -- bodies until it has elaborated all of the declarative
1934 -- part. But Is_Frozen will not be set at this point because
1935 -- we are processing code in lexical order.
1936
1937 -- We detect this case by going up the Scope chain of Rec
1938 -- and seeing if we have a subprogram scope before reaching
1939 -- the top of the scope chain or that of Comp'Base. If we
1940 -- do, then mark that Comp'Base will actually be frozen. If
1941 -- so, we merely undelay it.
1942
1943 S := Scope (Rec);
1944 while Present (S) loop
1945 if Is_Subprogram (S) then
1946 Will_Be_Frozen := True;
1947 exit;
1948 elsif S = Scope (Base_Type (Comp)) then
1949 exit;
1950 end if;
1951
1952 S := Scope (S);
1953 end loop;
1954
1955 if Will_Be_Frozen then
1956 Undelay_Type (Comp);
1957 else
1958 if Present (Prev) then
1959 Set_Next_Entity (Prev, Next_Entity (Comp));
1960 else
1961 Set_First_Entity (Rec, Next_Entity (Comp));
1962 end if;
1963
1964 -- Insert in entity list of scope of base type (which
1965 -- must be an enclosing scope, because still unfrozen).
1966
1967 Append_Entity (Comp, Scope (Base_Type (Comp)));
1968 end if;
1969 end;
1970
1971 -- If the component is an access type with an allocator as default
1972 -- value, the designated type will be frozen by the corresponding
1973 -- expression in init_proc. In order to place the freeze node for
1974 -- the designated type before that for the current record type,
1975 -- freeze it now.
1976
1977 -- Same process if the component is an array of access types,
1978 -- initialized with an aggregate. If the designated type is
1979 -- private, it cannot contain allocators, and it is premature
1980 -- to freeze the type, so we check for this as well.
1981
1982 elsif Is_Access_Type (Etype (Comp))
1983 and then Present (Parent (Comp))
1984 and then Present (Expression (Parent (Comp)))
1985 then
1986 declare
1987 Alloc : constant Node_Id :=
1988 Check_Allocator (Expression (Parent (Comp)));
1989
1990 begin
1991 if Present (Alloc) then
1992
1993 -- If component is pointer to a classwide type, freeze
1994 -- the specific type in the expression being allocated.
1995 -- The expression may be a subtype indication, in which
1996 -- case freeze the subtype mark.
1997
1998 if Is_Class_Wide_Type
1999 (Designated_Type (Etype (Comp)))
2000 then
2001 if Is_Entity_Name (Expression (Alloc)) then
2002 Freeze_And_Append
2003 (Entity (Expression (Alloc)), N, Result);
2004 elsif
2005 Nkind (Expression (Alloc)) = N_Subtype_Indication
2006 then
2007 Freeze_And_Append
2008 (Entity (Subtype_Mark (Expression (Alloc))),
2009 N, Result);
2010 end if;
2011
2012 elsif Is_Itype (Designated_Type (Etype (Comp))) then
2013 Check_Itype (Etype (Comp));
2014
2015 else
2016 Freeze_And_Append
2017 (Designated_Type (Etype (Comp)), N, Result);
2018 end if;
2019 end if;
2020 end;
2021
2022 elsif Is_Access_Type (Etype (Comp))
2023 and then Is_Itype (Designated_Type (Etype (Comp)))
2024 then
2025 Check_Itype (Etype (Comp));
2026
2027 elsif Is_Array_Type (Etype (Comp))
2028 and then Is_Access_Type (Component_Type (Etype (Comp)))
2029 and then Present (Parent (Comp))
2030 and then Nkind (Parent (Comp)) = N_Component_Declaration
2031 and then Present (Expression (Parent (Comp)))
2032 and then Nkind (Expression (Parent (Comp))) = N_Aggregate
2033 and then Is_Fully_Defined
2034 (Designated_Type (Component_Type (Etype (Comp))))
2035 then
2036 Freeze_And_Append
2037 (Designated_Type
2038 (Component_Type (Etype (Comp))), N, Result);
2039 end if;
2040
2041 Prev := Comp;
2042 Next_Entity (Comp);
2043 end loop;
2044
2045 -- Deal with Bit_Order aspect specifying a non-default bit order
2046
2047 if Reverse_Bit_Order (Rec) and then Base_Type (Rec) = Rec then
2048 if not Placed_Component then
2049 ADC :=
2050 Get_Attribute_Definition_Clause (Rec, Attribute_Bit_Order);
2051 Error_Msg_N ("?Bit_Order specification has no effect", ADC);
2052 Error_Msg_N
2053 ("\?since no component clauses were specified", ADC);
2054
2055 -- Here is where we do the processing for reversed bit order
2056
2057 else
2058 Adjust_Record_For_Reverse_Bit_Order (Rec);
2059 end if;
2060 end if;
2061
2062 -- Complete error checking on record representation clause (e.g.
2063 -- overlap of components). This is called after adjusting the
2064 -- record for reverse bit order.
2065
2066 declare
2067 RRC : constant Node_Id := Get_Record_Representation_Clause (Rec);
2068 begin
2069 if Present (RRC) then
2070 Check_Record_Representation_Clause (RRC);
2071 end if;
2072 end;
2073
2074 -- Set OK_To_Reorder_Components depending on debug flags
2075
2076 if Is_Base_Type (Rec) and then Convention (Rec) = Convention_Ada then
2077 if (Has_Discriminants (Rec) and then Debug_Flag_Dot_V)
2078 or else
2079 (not Has_Discriminants (Rec) and then Debug_Flag_Dot_R)
2080 then
2081 Set_OK_To_Reorder_Components (Rec);
2082 end if;
2083 end if;
2084
2085 -- Check for useless pragma Pack when all components placed. We only
2086 -- do this check for record types, not subtypes, since a subtype may
2087 -- have all its components placed, and it still makes perfectly good
2088 -- sense to pack other subtypes or the parent type. We do not give
2089 -- this warning if Optimize_Alignment is set to Space, since the
2090 -- pragma Pack does have an effect in this case (it always resets
2091 -- the alignment to one).
2092
2093 if Ekind (Rec) = E_Record_Type
2094 and then Is_Packed (Rec)
2095 and then not Unplaced_Component
2096 and then Optimize_Alignment /= 'S'
2097 then
2098 -- Reset packed status. Probably not necessary, but we do it so
2099 -- that there is no chance of the back end doing something strange
2100 -- with this redundant indication of packing.
2101
2102 Set_Is_Packed (Rec, False);
2103
2104 -- Give warning if redundant constructs warnings on
2105
2106 if Warn_On_Redundant_Constructs then
2107 Error_Msg_N -- CODEFIX
2108 ("?pragma Pack has no effect, no unplaced components",
2109 Get_Rep_Pragma (Rec, Name_Pack));
2110 end if;
2111 end if;
2112
2113 -- If this is the record corresponding to a remote type, freeze the
2114 -- remote type here since that is what we are semantically freezing.
2115 -- This prevents the freeze node for that type in an inner scope.
2116
2117 -- Also, Check for controlled components and unchecked unions.
2118 -- Finally, enforce the restriction that access attributes with a
2119 -- current instance prefix can only apply to limited types.
2120
2121 if Ekind (Rec) = E_Record_Type then
2122 if Present (Corresponding_Remote_Type (Rec)) then
2123 Freeze_And_Append (Corresponding_Remote_Type (Rec), N, Result);
2124 end if;
2125
2126 Comp := First_Component (Rec);
2127 while Present (Comp) loop
2128
2129 -- Do not set Has_Controlled_Component on a class-wide
2130 -- equivalent type. See Make_CW_Equivalent_Type.
2131
2132 if not Is_Class_Wide_Equivalent_Type (Rec)
2133 and then (Has_Controlled_Component (Etype (Comp))
2134 or else (Chars (Comp) /= Name_uParent
2135 and then Is_Controlled (Etype (Comp)))
2136 or else (Is_Protected_Type (Etype (Comp))
2137 and then Present
2138 (Corresponding_Record_Type
2139 (Etype (Comp)))
2140 and then Has_Controlled_Component
2141 (Corresponding_Record_Type
2142 (Etype (Comp)))))
2143 then
2144 Set_Has_Controlled_Component (Rec);
2145 exit;
2146 end if;
2147
2148 if Has_Unchecked_Union (Etype (Comp)) then
2149 Set_Has_Unchecked_Union (Rec);
2150 end if;
2151
2152 if Has_Per_Object_Constraint (Comp) then
2153
2154 -- Scan component declaration for likely misuses of current
2155 -- instance, either in a constraint or a default expression.
2156
2157 Check_Current_Instance (Parent (Comp));
2158 end if;
2159
2160 Next_Component (Comp);
2161 end loop;
2162 end if;
2163
2164 Set_Component_Alignment_If_Not_Set (Rec);
2165
2166 -- For first subtypes, check if there are any fixed-point fields with
2167 -- component clauses, where we must check the size. This is not done
2168 -- till the freeze point, since for fixed-point types, we do not know
2169 -- the size until the type is frozen. Similar processing applies to
2170 -- bit packed arrays.
2171
2172 if Is_First_Subtype (Rec) then
2173 Comp := First_Component (Rec);
2174 while Present (Comp) loop
2175 if Present (Component_Clause (Comp))
2176 and then (Is_Fixed_Point_Type (Etype (Comp))
2177 or else
2178 Is_Bit_Packed_Array (Etype (Comp)))
2179 then
2180 Check_Size
2181 (Component_Name (Component_Clause (Comp)),
2182 Etype (Comp),
2183 Esize (Comp),
2184 Junk);
2185 end if;
2186
2187 Next_Component (Comp);
2188 end loop;
2189 end if;
2190
2191 -- Generate warning for applying C or C++ convention to a record
2192 -- with discriminants. This is suppressed for the unchecked union
2193 -- case, since the whole point in this case is interface C. We also
2194 -- do not generate this within instantiations, since we will have
2195 -- generated a message on the template.
2196
2197 if Has_Discriminants (E)
2198 and then not Is_Unchecked_Union (E)
2199 and then (Convention (E) = Convention_C
2200 or else
2201 Convention (E) = Convention_CPP)
2202 and then Comes_From_Source (E)
2203 and then not In_Instance
2204 and then not Has_Warnings_Off (E)
2205 and then not Has_Warnings_Off (Base_Type (E))
2206 then
2207 declare
2208 Cprag : constant Node_Id := Get_Rep_Pragma (E, Name_Convention);
2209 A2 : Node_Id;
2210
2211 begin
2212 if Present (Cprag) then
2213 A2 := Next (First (Pragma_Argument_Associations (Cprag)));
2214
2215 if Convention (E) = Convention_C then
2216 Error_Msg_N
2217 ("?variant record has no direct equivalent in C", A2);
2218 else
2219 Error_Msg_N
2220 ("?variant record has no direct equivalent in C++", A2);
2221 end if;
2222
2223 Error_Msg_NE
2224 ("\?use of convention for type& is dubious", A2, E);
2225 end if;
2226 end;
2227 end if;
2228
2229 -- See if Size is too small as is (and implicit packing might help)
2230
2231 if not Is_Packed (Rec)
2232
2233 -- No implicit packing if even one component is explicitly placed
2234
2235 and then not Placed_Component
2236
2237 -- Must have size clause and all scalar components
2238
2239 and then Has_Size_Clause (Rec)
2240 and then All_Scalar_Components
2241
2242 -- Do not try implicit packing on records with discriminants, too
2243 -- complicated, especially in the variant record case.
2244
2245 and then not Has_Discriminants (Rec)
2246
2247 -- We can implicitly pack if the specified size of the record is
2248 -- less than the sum of the object sizes (no point in packing if
2249 -- this is not the case).
2250
2251 and then RM_Size (Rec) < Scalar_Component_Total_Esize
2252
2253 -- And the total RM size cannot be greater than the specified size
2254 -- since otherwise packing will not get us where we have to be!
2255
2256 and then RM_Size (Rec) >= Scalar_Component_Total_RM_Size
2257
2258 -- Never do implicit packing in CodePeer or Alfa modes since
2259 -- we don't do any packing in these modes, since this generates
2260 -- over-complex code that confuses static analysis, and in
2261 -- general, neither CodePeer not GNATprove care about the
2262 -- internal representation of objects.
2263
2264 and then not (CodePeer_Mode or Alfa_Mode)
2265 then
2266 -- If implicit packing enabled, do it
2267
2268 if Implicit_Packing then
2269 Set_Is_Packed (Rec);
2270
2271 -- Otherwise flag the size clause
2272
2273 else
2274 declare
2275 Sz : constant Node_Id := Size_Clause (Rec);
2276 begin
2277 Error_Msg_NE -- CODEFIX
2278 ("size given for& too small", Sz, Rec);
2279 Error_Msg_N -- CODEFIX
2280 ("\use explicit pragma Pack "
2281 & "or use pragma Implicit_Packing", Sz);
2282 end;
2283 end if;
2284 end if;
2285 end Freeze_Record_Type;
2286
2287 -- Start of processing for Freeze_Entity
2288
2289 begin
2290 -- We are going to test for various reasons why this entity need not be
2291 -- frozen here, but in the case of an Itype that's defined within a
2292 -- record, that test actually applies to the record.
2293
2294 if Is_Itype (E) and then Is_Record_Type (Scope (E)) then
2295 Test_E := Scope (E);
2296 elsif Is_Itype (E) and then Present (Underlying_Type (Scope (E)))
2297 and then Is_Record_Type (Underlying_Type (Scope (E)))
2298 then
2299 Test_E := Underlying_Type (Scope (E));
2300 end if;
2301
2302 -- Do not freeze if already frozen since we only need one freeze node
2303
2304 if Is_Frozen (E) then
2305 return No_List;
2306
2307 -- It is improper to freeze an external entity within a generic because
2308 -- its freeze node will appear in a non-valid context. The entity will
2309 -- be frozen in the proper scope after the current generic is analyzed.
2310
2311 elsif Inside_A_Generic and then External_Ref_In_Generic (Test_E) then
2312 return No_List;
2313
2314 -- AI05-0213: A formal incomplete type does not freeze the actual. In
2315 -- the instance, the same applies to the subtype renaming the actual.
2316
2317 elsif Is_Private_Type (E)
2318 and then Is_Generic_Actual_Type (E)
2319 and then No (Full_View (Base_Type (E)))
2320 and then Ada_Version >= Ada_2012
2321 then
2322 return No_List;
2323
2324 -- Do not freeze a global entity within an inner scope created during
2325 -- expansion. A call to subprogram E within some internal procedure
2326 -- (a stream attribute for example) might require freezing E, but the
2327 -- freeze node must appear in the same declarative part as E itself.
2328 -- The two-pass elaboration mechanism in gigi guarantees that E will
2329 -- be frozen before the inner call is elaborated. We exclude constants
2330 -- from this test, because deferred constants may be frozen early, and
2331 -- must be diagnosed (e.g. in the case of a deferred constant being used
2332 -- in a default expression). If the enclosing subprogram comes from
2333 -- source, or is a generic instance, then the freeze point is the one
2334 -- mandated by the language, and we freeze the entity. A subprogram that
2335 -- is a child unit body that acts as a spec does not have a spec that
2336 -- comes from source, but can only come from source.
2337
2338 elsif In_Open_Scopes (Scope (Test_E))
2339 and then Scope (Test_E) /= Current_Scope
2340 and then Ekind (Test_E) /= E_Constant
2341 then
2342 declare
2343 S : Entity_Id;
2344
2345 begin
2346 S := Current_Scope;
2347 while Present (S) loop
2348 if Is_Overloadable (S) then
2349 if Comes_From_Source (S)
2350 or else Is_Generic_Instance (S)
2351 or else Is_Child_Unit (S)
2352 then
2353 exit;
2354 else
2355 return No_List;
2356 end if;
2357 end if;
2358
2359 S := Scope (S);
2360 end loop;
2361 end;
2362
2363 -- Similarly, an inlined instance body may make reference to global
2364 -- entities, but these references cannot be the proper freezing point
2365 -- for them, and in the absence of inlining freezing will take place in
2366 -- their own scope. Normally instance bodies are analyzed after the
2367 -- enclosing compilation, and everything has been frozen at the proper
2368 -- place, but with front-end inlining an instance body is compiled
2369 -- before the end of the enclosing scope, and as a result out-of-order
2370 -- freezing must be prevented.
2371
2372 elsif Front_End_Inlining
2373 and then In_Instance_Body
2374 and then Present (Scope (Test_E))
2375 then
2376 declare
2377 S : Entity_Id;
2378
2379 begin
2380 S := Scope (Test_E);
2381 while Present (S) loop
2382 if Is_Generic_Instance (S) then
2383 exit;
2384 else
2385 S := Scope (S);
2386 end if;
2387 end loop;
2388
2389 if No (S) then
2390 return No_List;
2391 end if;
2392 end;
2393 end if;
2394
2395 -- Deal with delayed aspect specifications. The analysis of the aspect
2396 -- is required to be delayed to the freeze point, so we evaluate the
2397 -- pragma or attribute definition clause in the tree at this point.
2398
2399 if Has_Delayed_Aspects (E) then
2400 declare
2401 Ritem : Node_Id;
2402 Aitem : Node_Id;
2403
2404 begin
2405 -- Look for aspect specification entries for this entity
2406
2407 Ritem := First_Rep_Item (E);
2408 while Present (Ritem) loop
2409 if Nkind (Ritem) = N_Aspect_Specification
2410 and then Entity (Ritem) = E
2411 and then Is_Delayed_Aspect (Ritem)
2412 and then Scope (E) = Current_Scope
2413 then
2414 Aitem := Aspect_Rep_Item (Ritem);
2415
2416 -- Skip if this is an aspect with no corresponding pragma
2417 -- or attribute definition node (such as Default_Value).
2418
2419 if Present (Aitem) then
2420 Set_Parent (Aitem, Ritem);
2421 Analyze (Aitem);
2422 end if;
2423 end if;
2424
2425 Next_Rep_Item (Ritem);
2426 end loop;
2427 end;
2428 end if;
2429
2430 -- Here to freeze the entity
2431
2432 Set_Is_Frozen (E);
2433
2434 -- Case of entity being frozen is other than a type
2435
2436 if not Is_Type (E) then
2437
2438 -- If entity is exported or imported and does not have an external
2439 -- name, now is the time to provide the appropriate default name.
2440 -- Skip this if the entity is stubbed, since we don't need a name
2441 -- for any stubbed routine. For the case on intrinsics, if no
2442 -- external name is specified, then calls will be handled in
2443 -- Exp_Intr.Expand_Intrinsic_Call, and no name is needed. If an
2444 -- external name is provided, then Expand_Intrinsic_Call leaves
2445 -- calls in place for expansion by GIGI.
2446
2447 if (Is_Imported (E) or else Is_Exported (E))
2448 and then No (Interface_Name (E))
2449 and then Convention (E) /= Convention_Stubbed
2450 and then Convention (E) /= Convention_Intrinsic
2451 then
2452 Set_Encoded_Interface_Name
2453 (E, Get_Default_External_Name (E));
2454
2455 -- If entity is an atomic object appearing in a declaration and
2456 -- the expression is an aggregate, assign it to a temporary to
2457 -- ensure that the actual assignment is done atomically rather
2458 -- than component-wise (the assignment to the temp may be done
2459 -- component-wise, but that is harmless).
2460
2461 elsif Is_Atomic (E)
2462 and then Nkind (Parent (E)) = N_Object_Declaration
2463 and then Present (Expression (Parent (E)))
2464 and then Nkind (Expression (Parent (E))) = N_Aggregate
2465 and then Is_Atomic_Aggregate (Expression (Parent (E)), Etype (E))
2466 then
2467 null;
2468 end if;
2469
2470 -- For a subprogram, freeze all parameter types and also the return
2471 -- type (RM 13.14(14)). However skip this for internal subprograms.
2472 -- This is also the point where any extra formal parameters are
2473 -- created since we now know whether the subprogram will use a
2474 -- foreign convention.
2475
2476 if Is_Subprogram (E) then
2477 if not Is_Internal (E) then
2478 declare
2479 F_Type : Entity_Id;
2480 R_Type : Entity_Id;
2481 Warn_Node : Node_Id;
2482
2483 begin
2484 -- Loop through formals
2485
2486 Formal := First_Formal (E);
2487 while Present (Formal) loop
2488 F_Type := Etype (Formal);
2489
2490 -- AI05-0151 : incomplete types can appear in a profile.
2491 -- By the time the entity is frozen, the full view must
2492 -- be available, unless it is a limited view.
2493
2494 if Is_Incomplete_Type (F_Type)
2495 and then Present (Full_View (F_Type))
2496 then
2497 F_Type := Full_View (F_Type);
2498 Set_Etype (Formal, F_Type);
2499 end if;
2500
2501 Freeze_And_Append (F_Type, N, Result);
2502
2503 if Is_Private_Type (F_Type)
2504 and then Is_Private_Type (Base_Type (F_Type))
2505 and then No (Full_View (Base_Type (F_Type)))
2506 and then not Is_Generic_Type (F_Type)
2507 and then not Is_Derived_Type (F_Type)
2508 then
2509 -- If the type of a formal is incomplete, subprogram
2510 -- is being frozen prematurely. Within an instance
2511 -- (but not within a wrapper package) this is an
2512 -- artifact of our need to regard the end of an
2513 -- instantiation as a freeze point. Otherwise it is
2514 -- a definite error.
2515
2516 if In_Instance then
2517 Set_Is_Frozen (E, False);
2518 return No_List;
2519
2520 elsif not After_Last_Declaration
2521 and then not Freezing_Library_Level_Tagged_Type
2522 then
2523 Error_Msg_Node_1 := F_Type;
2524 Error_Msg
2525 ("type& must be fully defined before this point",
2526 Loc);
2527 end if;
2528 end if;
2529
2530 -- Check suspicious parameter for C function. These tests
2531 -- apply only to exported/imported subprograms.
2532
2533 if Warn_On_Export_Import
2534 and then Comes_From_Source (E)
2535 and then (Convention (E) = Convention_C
2536 or else
2537 Convention (E) = Convention_CPP)
2538 and then (Is_Imported (E) or else Is_Exported (E))
2539 and then Convention (E) /= Convention (Formal)
2540 and then not Has_Warnings_Off (E)
2541 and then not Has_Warnings_Off (F_Type)
2542 and then not Has_Warnings_Off (Formal)
2543 then
2544 -- Qualify mention of formals with subprogram name
2545
2546 Error_Msg_Qual_Level := 1;
2547
2548 -- Check suspicious use of fat C pointer
2549
2550 if Is_Access_Type (F_Type)
2551 and then Esize (F_Type) > Ttypes.System_Address_Size
2552 then
2553 Error_Msg_N
2554 ("?type of & does not correspond to C pointer!",
2555 Formal);
2556
2557 -- Check suspicious return of boolean
2558
2559 elsif Root_Type (F_Type) = Standard_Boolean
2560 and then Convention (F_Type) = Convention_Ada
2561 and then not Has_Warnings_Off (F_Type)
2562 and then not Has_Size_Clause (F_Type)
2563 and then VM_Target = No_VM
2564 then
2565 Error_Msg_N ("& is an 8-bit Ada Boolean?", Formal);
2566 Error_Msg_N
2567 ("\use appropriate corresponding type in C "
2568 & "(e.g. char)?", Formal);
2569
2570 -- Check suspicious tagged type
2571
2572 elsif (Is_Tagged_Type (F_Type)
2573 or else (Is_Access_Type (F_Type)
2574 and then
2575 Is_Tagged_Type
2576 (Designated_Type (F_Type))))
2577 and then Convention (E) = Convention_C
2578 then
2579 Error_Msg_N
2580 ("?& involves a tagged type which does not "
2581 & "correspond to any C type!", Formal);
2582
2583 -- Check wrong convention subprogram pointer
2584
2585 elsif Ekind (F_Type) = E_Access_Subprogram_Type
2586 and then not Has_Foreign_Convention (F_Type)
2587 then
2588 Error_Msg_N
2589 ("?subprogram pointer & should "
2590 & "have foreign convention!", Formal);
2591 Error_Msg_Sloc := Sloc (F_Type);
2592 Error_Msg_NE
2593 ("\?add Convention pragma to declaration of &#",
2594 Formal, F_Type);
2595 end if;
2596
2597 -- Turn off name qualification after message output
2598
2599 Error_Msg_Qual_Level := 0;
2600 end if;
2601
2602 -- Check for unconstrained array in exported foreign
2603 -- convention case.
2604
2605 if Has_Foreign_Convention (E)
2606 and then not Is_Imported (E)
2607 and then Is_Array_Type (F_Type)
2608 and then not Is_Constrained (F_Type)
2609 and then Warn_On_Export_Import
2610
2611 -- Exclude VM case, since both .NET and JVM can handle
2612 -- unconstrained arrays without a problem.
2613
2614 and then VM_Target = No_VM
2615 then
2616 Error_Msg_Qual_Level := 1;
2617
2618 -- If this is an inherited operation, place the
2619 -- warning on the derived type declaration, rather
2620 -- than on the original subprogram.
2621
2622 if Nkind (Original_Node (Parent (E))) =
2623 N_Full_Type_Declaration
2624 then
2625 Warn_Node := Parent (E);
2626
2627 if Formal = First_Formal (E) then
2628 Error_Msg_NE
2629 ("?in inherited operation&", Warn_Node, E);
2630 end if;
2631 else
2632 Warn_Node := Formal;
2633 end if;
2634
2635 Error_Msg_NE
2636 ("?type of argument& is unconstrained array",
2637 Warn_Node, Formal);
2638 Error_Msg_NE
2639 ("?foreign caller must pass bounds explicitly",
2640 Warn_Node, Formal);
2641 Error_Msg_Qual_Level := 0;
2642 end if;
2643
2644 if not From_With_Type (F_Type) then
2645 if Is_Access_Type (F_Type) then
2646 F_Type := Designated_Type (F_Type);
2647 end if;
2648
2649 -- If the formal is an anonymous_access_to_subprogram
2650 -- freeze the subprogram type as well, to prevent
2651 -- scope anomalies in gigi, because there is no other
2652 -- clear point at which it could be frozen.
2653
2654 if Is_Itype (Etype (Formal))
2655 and then Ekind (F_Type) = E_Subprogram_Type
2656 then
2657 Freeze_And_Append (F_Type, N, Result);
2658 end if;
2659 end if;
2660
2661 Next_Formal (Formal);
2662 end loop;
2663
2664 -- Case of function: similar checks on return type
2665
2666 if Ekind (E) = E_Function then
2667
2668 -- Freeze return type
2669
2670 R_Type := Etype (E);
2671
2672 -- AI05-0151: the return type may have been incomplete
2673 -- at the point of declaration.
2674
2675 if Ekind (R_Type) = E_Incomplete_Type
2676 and then Present (Full_View (R_Type))
2677 then
2678 R_Type := Full_View (R_Type);
2679 Set_Etype (E, R_Type);
2680 end if;
2681
2682 Freeze_And_Append (R_Type, N, Result);
2683
2684 -- Check suspicious return type for C function
2685
2686 if Warn_On_Export_Import
2687 and then (Convention (E) = Convention_C
2688 or else
2689 Convention (E) = Convention_CPP)
2690 and then (Is_Imported (E) or else Is_Exported (E))
2691 then
2692 -- Check suspicious return of fat C pointer
2693
2694 if Is_Access_Type (R_Type)
2695 and then Esize (R_Type) > Ttypes.System_Address_Size
2696 and then not Has_Warnings_Off (E)
2697 and then not Has_Warnings_Off (R_Type)
2698 then
2699 Error_Msg_N
2700 ("?return type of& does not "
2701 & "correspond to C pointer!", E);
2702
2703 -- Check suspicious return of boolean
2704
2705 elsif Root_Type (R_Type) = Standard_Boolean
2706 and then Convention (R_Type) = Convention_Ada
2707 and then VM_Target = No_VM
2708 and then not Has_Warnings_Off (E)
2709 and then not Has_Warnings_Off (R_Type)
2710 and then not Has_Size_Clause (R_Type)
2711 then
2712 declare
2713 N : constant Node_Id :=
2714 Result_Definition (Declaration_Node (E));
2715 begin
2716 Error_Msg_NE
2717 ("return type of & is an 8-bit Ada Boolean?",
2718 N, E);
2719 Error_Msg_NE
2720 ("\use appropriate corresponding type in C "
2721 & "(e.g. char)?", N, E);
2722 end;
2723
2724 -- Check suspicious return tagged type
2725
2726 elsif (Is_Tagged_Type (R_Type)
2727 or else (Is_Access_Type (R_Type)
2728 and then
2729 Is_Tagged_Type
2730 (Designated_Type (R_Type))))
2731 and then Convention (E) = Convention_C
2732 and then not Has_Warnings_Off (E)
2733 and then not Has_Warnings_Off (R_Type)
2734 then
2735 Error_Msg_N
2736 ("?return type of & does not "
2737 & "correspond to C type!", E);
2738
2739 -- Check return of wrong convention subprogram pointer
2740
2741 elsif Ekind (R_Type) = E_Access_Subprogram_Type
2742 and then not Has_Foreign_Convention (R_Type)
2743 and then not Has_Warnings_Off (E)
2744 and then not Has_Warnings_Off (R_Type)
2745 then
2746 Error_Msg_N
2747 ("?& should return a foreign "
2748 & "convention subprogram pointer", E);
2749 Error_Msg_Sloc := Sloc (R_Type);
2750 Error_Msg_NE
2751 ("\?add Convention pragma to declaration of& #",
2752 E, R_Type);
2753 end if;
2754 end if;
2755
2756 -- Give warning for suspicious return of a result of an
2757 -- unconstrained array type in a foreign convention
2758 -- function.
2759
2760 if Has_Foreign_Convention (E)
2761
2762 -- We are looking for a return of unconstrained array
2763
2764 and then Is_Array_Type (R_Type)
2765 and then not Is_Constrained (R_Type)
2766
2767 -- Exclude imported routines, the warning does not
2768 -- belong on the import, but rather on the routine
2769 -- definition.
2770
2771 and then not Is_Imported (E)
2772
2773 -- Exclude VM case, since both .NET and JVM can handle
2774 -- return of unconstrained arrays without a problem.
2775
2776 and then VM_Target = No_VM
2777
2778 -- Check that general warning is enabled, and that it
2779 -- is not suppressed for this particular case.
2780
2781 and then Warn_On_Export_Import
2782 and then not Has_Warnings_Off (E)
2783 and then not Has_Warnings_Off (R_Type)
2784 then
2785 Error_Msg_N
2786 ("?foreign convention function& should not " &
2787 "return unconstrained array!", E);
2788 end if;
2789 end if;
2790 end;
2791 end if;
2792
2793 -- Must freeze its parent first if it is a derived subprogram
2794
2795 if Present (Alias (E)) then
2796 Freeze_And_Append (Alias (E), N, Result);
2797 end if;
2798
2799 -- We don't freeze internal subprograms, because we don't normally
2800 -- want addition of extra formals or mechanism setting to happen
2801 -- for those. However we do pass through predefined dispatching
2802 -- cases, since extra formals may be needed in some cases, such as
2803 -- for the stream 'Input function (build-in-place formals).
2804
2805 if not Is_Internal (E)
2806 or else Is_Predefined_Dispatching_Operation (E)
2807 then
2808 Freeze_Subprogram (E);
2809 end if;
2810
2811 -- Here for other than a subprogram or type
2812
2813 else
2814 -- If entity has a type, and it is not a generic unit, then
2815 -- freeze it first (RM 13.14(10)).
2816
2817 if Present (Etype (E))
2818 and then Ekind (E) /= E_Generic_Function
2819 then
2820 Freeze_And_Append (Etype (E), N, Result);
2821 end if;
2822
2823 -- Special processing for objects created by object declaration
2824
2825 if Nkind (Declaration_Node (E)) = N_Object_Declaration then
2826
2827 -- Abstract type allowed only for C++ imported variables or
2828 -- constants.
2829
2830 -- Note: we inhibit this check for objects that do not come
2831 -- from source because there is at least one case (the
2832 -- expansion of x'Class'Input where x is abstract) where we
2833 -- legitimately generate an abstract object.
2834
2835 if Is_Abstract_Type (Etype (E))
2836 and then Comes_From_Source (Parent (E))
2837 and then not (Is_Imported (E)
2838 and then Is_CPP_Class (Etype (E)))
2839 then
2840 Error_Msg_N ("type of object cannot be abstract",
2841 Object_Definition (Parent (E)));
2842
2843 if Is_CPP_Class (Etype (E)) then
2844 Error_Msg_NE
2845 ("\} may need a cpp_constructor",
2846 Object_Definition (Parent (E)), Etype (E));
2847 end if;
2848 end if;
2849
2850 -- For object created by object declaration, perform required
2851 -- categorization (preelaborate and pure) checks. Defer these
2852 -- checks to freeze time since pragma Import inhibits default
2853 -- initialization and thus pragma Import affects these checks.
2854
2855 Validate_Object_Declaration (Declaration_Node (E));
2856
2857 -- If there is an address clause, check that it is valid
2858
2859 Check_Address_Clause (E);
2860
2861 -- If the object needs any kind of default initialization, an
2862 -- error must be issued if No_Default_Initialization applies.
2863 -- The check doesn't apply to imported objects, which are not
2864 -- ever default initialized, and is why the check is deferred
2865 -- until freezing, at which point we know if Import applies.
2866 -- Deferred constants are also exempted from this test because
2867 -- their completion is explicit, or through an import pragma.
2868
2869 if Ekind (E) = E_Constant
2870 and then Present (Full_View (E))
2871 then
2872 null;
2873
2874 elsif Comes_From_Source (E)
2875 and then not Is_Imported (E)
2876 and then not Has_Init_Expression (Declaration_Node (E))
2877 and then
2878 ((Has_Non_Null_Base_Init_Proc (Etype (E))
2879 and then not No_Initialization (Declaration_Node (E))
2880 and then not Is_Value_Type (Etype (E))
2881 and then not Initialization_Suppressed (Etype (E)))
2882 or else
2883 (Needs_Simple_Initialization (Etype (E))
2884 and then not Is_Internal (E)))
2885 then
2886 Has_Default_Initialization := True;
2887 Check_Restriction
2888 (No_Default_Initialization, Declaration_Node (E));
2889 end if;
2890
2891 -- Check that a Thread_Local_Storage variable does not have
2892 -- default initialization, and any explicit initialization must
2893 -- either be the null constant or a static constant.
2894
2895 if Has_Pragma_Thread_Local_Storage (E) then
2896 declare
2897 Decl : constant Node_Id := Declaration_Node (E);
2898 begin
2899 if Has_Default_Initialization
2900 or else
2901 (Has_Init_Expression (Decl)
2902 and then
2903 (No (Expression (Decl))
2904 or else not
2905 (Is_Static_Expression (Expression (Decl))
2906 or else
2907 Nkind (Expression (Decl)) = N_Null)))
2908 then
2909 Error_Msg_NE
2910 ("Thread_Local_Storage variable& is "
2911 & "improperly initialized", Decl, E);
2912 Error_Msg_NE
2913 ("\only allowed initialization is explicit "
2914 & "NULL or static expression", Decl, E);
2915 end if;
2916 end;
2917 end if;
2918
2919 -- For imported objects, set Is_Public unless there is also an
2920 -- address clause, which means that there is no external symbol
2921 -- needed for the Import (Is_Public may still be set for other
2922 -- unrelated reasons). Note that we delayed this processing
2923 -- till freeze time so that we can be sure not to set the flag
2924 -- if there is an address clause. If there is such a clause,
2925 -- then the only purpose of the Import pragma is to suppress
2926 -- implicit initialization.
2927
2928 if Is_Imported (E)
2929 and then No (Address_Clause (E))
2930 then
2931 Set_Is_Public (E);
2932 end if;
2933
2934 -- For convention C objects of an enumeration type, warn if
2935 -- the size is not integer size and no explicit size given.
2936 -- Skip warning for Boolean, and Character, assume programmer
2937 -- expects 8-bit sizes for these cases.
2938
2939 if (Convention (E) = Convention_C
2940 or else
2941 Convention (E) = Convention_CPP)
2942 and then Is_Enumeration_Type (Etype (E))
2943 and then not Is_Character_Type (Etype (E))
2944 and then not Is_Boolean_Type (Etype (E))
2945 and then Esize (Etype (E)) < Standard_Integer_Size
2946 and then not Has_Size_Clause (E)
2947 then
2948 Error_Msg_Uint_1 := UI_From_Int (Standard_Integer_Size);
2949 Error_Msg_N
2950 ("?convention C enumeration object has size less than ^",
2951 E);
2952 Error_Msg_N ("\?use explicit size clause to set size", E);
2953 end if;
2954 end if;
2955
2956 -- Check that a constant which has a pragma Volatile[_Components]
2957 -- or Atomic[_Components] also has a pragma Import (RM C.6(13)).
2958
2959 -- Note: Atomic[_Components] also sets Volatile[_Components]
2960
2961 if Ekind (E) = E_Constant
2962 and then (Has_Volatile_Components (E) or else Is_Volatile (E))
2963 and then not Is_Imported (E)
2964 then
2965 -- Make sure we actually have a pragma, and have not merely
2966 -- inherited the indication from elsewhere (e.g. an address
2967 -- clause, which is not good enough in RM terms!)
2968
2969 if Has_Rep_Pragma (E, Name_Atomic)
2970 or else
2971 Has_Rep_Pragma (E, Name_Atomic_Components)
2972 then
2973 Error_Msg_N
2974 ("stand alone atomic constant must be " &
2975 "imported (RM C.6(13))", E);
2976
2977 elsif Has_Rep_Pragma (E, Name_Volatile)
2978 or else
2979 Has_Rep_Pragma (E, Name_Volatile_Components)
2980 then
2981 Error_Msg_N
2982 ("stand alone volatile constant must be " &
2983 "imported (RM C.6(13))", E);
2984 end if;
2985 end if;
2986
2987 -- Static objects require special handling
2988
2989 if (Ekind (E) = E_Constant or else Ekind (E) = E_Variable)
2990 and then Is_Statically_Allocated (E)
2991 then
2992 Freeze_Static_Object (E);
2993 end if;
2994
2995 -- Remaining step is to layout objects
2996
2997 if Ekind (E) = E_Variable
2998 or else
2999 Ekind (E) = E_Constant
3000 or else
3001 Ekind (E) = E_Loop_Parameter
3002 or else
3003 Is_Formal (E)
3004 then
3005 Layout_Object (E);
3006 end if;
3007 end if;
3008
3009 -- Case of a type or subtype being frozen
3010
3011 else
3012 -- We used to check here that a full type must have preelaborable
3013 -- initialization if it completes a private type specified with
3014 -- pragma Preelaborable_Initialization, but that missed cases where
3015 -- the types occur within a generic package, since the freezing
3016 -- that occurs within a containing scope generally skips traversal
3017 -- of a generic unit's declarations (those will be frozen within
3018 -- instances). This check was moved to Analyze_Package_Specification.
3019
3020 -- The type may be defined in a generic unit. This can occur when
3021 -- freezing a generic function that returns the type (which is
3022 -- defined in a parent unit). It is clearly meaningless to freeze
3023 -- this type. However, if it is a subtype, its size may be determi-
3024 -- nable and used in subsequent checks, so might as well try to
3025 -- compute it.
3026
3027 if Present (Scope (E))
3028 and then Is_Generic_Unit (Scope (E))
3029 then
3030 Check_Compile_Time_Size (E);
3031 return No_List;
3032 end if;
3033
3034 -- Deal with special cases of freezing for subtype
3035
3036 if E /= Base_Type (E) then
3037
3038 -- Before we do anything else, a specialized test for the case of
3039 -- a size given for an array where the array needs to be packed,
3040 -- but was not so the size cannot be honored. This would of course
3041 -- be caught by the backend, and indeed we don't catch all cases.
3042 -- The point is that we can give a better error message in those
3043 -- cases that we do catch with the circuitry here. Also if pragma
3044 -- Implicit_Packing is set, this is where the packing occurs.
3045
3046 -- The reason we do this so early is that the processing in the
3047 -- automatic packing case affects the layout of the base type, so
3048 -- it must be done before we freeze the base type.
3049
3050 if Is_Array_Type (E) then
3051 declare
3052 Lo, Hi : Node_Id;
3053 Ctyp : constant Entity_Id := Component_Type (E);
3054
3055 begin
3056 -- Check enabling conditions. These are straightforward
3057 -- except for the test for a limited composite type. This
3058 -- eliminates the rare case of a array of limited components
3059 -- where there are issues of whether or not we can go ahead
3060 -- and pack the array (since we can't freely pack and unpack
3061 -- arrays if they are limited).
3062
3063 -- Note that we check the root type explicitly because the
3064 -- whole point is we are doing this test before we have had
3065 -- a chance to freeze the base type (and it is that freeze
3066 -- action that causes stuff to be inherited).
3067
3068 if Present (Size_Clause (E))
3069 and then Known_Static_RM_Size (E)
3070 and then not Is_Packed (E)
3071 and then not Has_Pragma_Pack (E)
3072 and then Number_Dimensions (E) = 1
3073 and then not Has_Component_Size_Clause (E)
3074 and then Known_Static_RM_Size (Ctyp)
3075 and then not Is_Limited_Composite (E)
3076 and then not Is_Packed (Root_Type (E))
3077 and then not Has_Component_Size_Clause (Root_Type (E))
3078 and then not (CodePeer_Mode or Alfa_Mode)
3079 then
3080 Get_Index_Bounds (First_Index (E), Lo, Hi);
3081
3082 if Compile_Time_Known_Value (Lo)
3083 and then Compile_Time_Known_Value (Hi)
3084 and then Known_Static_RM_Size (Ctyp)
3085 and then RM_Size (Ctyp) < 64
3086 then
3087 declare
3088 Lov : constant Uint := Expr_Value (Lo);
3089 Hiv : constant Uint := Expr_Value (Hi);
3090 Len : constant Uint := UI_Max
3091 (Uint_0,
3092 Hiv - Lov + 1);
3093 Rsiz : constant Uint := RM_Size (Ctyp);
3094 SZ : constant Node_Id := Size_Clause (E);
3095 Btyp : constant Entity_Id := Base_Type (E);
3096
3097 -- What we are looking for here is the situation where
3098 -- the RM_Size given would be exactly right if there
3099 -- was a pragma Pack (resulting in the component size
3100 -- being the same as the RM_Size). Furthermore, the
3101 -- component type size must be an odd size (not a
3102 -- multiple of storage unit). If the component RM size
3103 -- is an exact number of storage units that is a power
3104 -- of two, the array is not packed and has a standard
3105 -- representation.
3106
3107 begin
3108 if RM_Size (E) = Len * Rsiz
3109 and then Rsiz mod System_Storage_Unit /= 0
3110 then
3111 -- For implicit packing mode, just set the
3112 -- component size silently.
3113
3114 if Implicit_Packing then
3115 Set_Component_Size (Btyp, Rsiz);
3116 Set_Is_Bit_Packed_Array (Btyp);
3117 Set_Is_Packed (Btyp);
3118 Set_Has_Non_Standard_Rep (Btyp);
3119
3120 -- Otherwise give an error message
3121
3122 else
3123 Error_Msg_NE
3124 ("size given for& too small", SZ, E);
3125 Error_Msg_N -- CODEFIX
3126 ("\use explicit pragma Pack "
3127 & "or use pragma Implicit_Packing", SZ);
3128 end if;
3129
3130 elsif RM_Size (E) = Len * Rsiz
3131 and then Implicit_Packing
3132 and then
3133 (Rsiz / System_Storage_Unit = 1
3134 or else Rsiz / System_Storage_Unit = 2
3135 or else Rsiz / System_Storage_Unit = 4)
3136 then
3137
3138 -- Not a packed array, but indicate the desired
3139 -- component size, for the back-end.
3140
3141 Set_Component_Size (Btyp, Rsiz);
3142 end if;
3143 end;
3144 end if;
3145 end if;
3146 end;
3147 end if;
3148
3149 -- If ancestor subtype present, freeze that first. Note that this
3150 -- will also get the base type frozen. Need RM reference ???
3151
3152 Atype := Ancestor_Subtype (E);
3153
3154 if Present (Atype) then
3155 Freeze_And_Append (Atype, N, Result);
3156
3157 -- No ancestor subtype present
3158
3159 else
3160 -- See if we have a nearest ancestor that has a predicate.
3161 -- That catches the case of derived type with a predicate.
3162 -- Need RM reference here ???
3163
3164 Atype := Nearest_Ancestor (E);
3165
3166 if Present (Atype) and then Has_Predicates (Atype) then
3167 Freeze_And_Append (Atype, N, Result);
3168 end if;
3169
3170 -- Freeze base type before freezing the entity (RM 13.14(15))
3171
3172 if E /= Base_Type (E) then
3173 Freeze_And_Append (Base_Type (E), N, Result);
3174 end if;
3175 end if;
3176
3177 -- For a derived type, freeze its parent type first (RM 13.14(15))
3178
3179 elsif Is_Derived_Type (E) then
3180 Freeze_And_Append (Etype (E), N, Result);
3181 Freeze_And_Append (First_Subtype (Etype (E)), N, Result);
3182 end if;
3183
3184 -- For array type, freeze index types and component type first
3185 -- before freezing the array (RM 13.14(15)).
3186
3187 if Is_Array_Type (E) then
3188 declare
3189 FS : constant Entity_Id := First_Subtype (E);
3190 Ctyp : constant Entity_Id := Component_Type (E);
3191 Clause : Entity_Id;
3192
3193 Non_Standard_Enum : Boolean := False;
3194 -- Set true if any of the index types is an enumeration type
3195 -- with a non-standard representation.
3196
3197 begin
3198 Freeze_And_Append (Ctyp, N, Result);
3199
3200 Indx := First_Index (E);
3201 while Present (Indx) loop
3202 Freeze_And_Append (Etype (Indx), N, Result);
3203
3204 if Is_Enumeration_Type (Etype (Indx))
3205 and then Has_Non_Standard_Rep (Etype (Indx))
3206 then
3207 Non_Standard_Enum := True;
3208 end if;
3209
3210 Next_Index (Indx);
3211 end loop;
3212
3213 -- Processing that is done only for base types
3214
3215 if Ekind (E) = E_Array_Type then
3216
3217 -- Propagate flags for component type
3218
3219 if Is_Controlled (Component_Type (E))
3220 or else Has_Controlled_Component (Ctyp)
3221 then
3222 Set_Has_Controlled_Component (E);
3223 end if;
3224
3225 if Has_Unchecked_Union (Component_Type (E)) then
3226 Set_Has_Unchecked_Union (E);
3227 end if;
3228
3229 -- If packing was requested or if the component size was set
3230 -- explicitly, then see if bit packing is required. This
3231 -- processing is only done for base types, since all the
3232 -- representation aspects involved are type-related. This
3233 -- is not just an optimization, if we start processing the
3234 -- subtypes, they interfere with the settings on the base
3235 -- type (this is because Is_Packed has a slightly different
3236 -- meaning before and after freezing).
3237
3238 declare
3239 Csiz : Uint;
3240 Esiz : Uint;
3241
3242 begin
3243 if (Is_Packed (E) or else Has_Pragma_Pack (E))
3244 and then Known_Static_RM_Size (Ctyp)
3245 and then not Has_Component_Size_Clause (E)
3246 then
3247 Csiz := UI_Max (RM_Size (Ctyp), 1);
3248
3249 elsif Known_Component_Size (E) then
3250 Csiz := Component_Size (E);
3251
3252 elsif not Known_Static_Esize (Ctyp) then
3253 Csiz := Uint_0;
3254
3255 else
3256 Esiz := Esize (Ctyp);
3257
3258 -- We can set the component size if it is less than
3259 -- 16, rounding it up to the next storage unit size.
3260
3261 if Esiz <= 8 then
3262 Csiz := Uint_8;
3263 elsif Esiz <= 16 then
3264 Csiz := Uint_16;
3265 else
3266 Csiz := Uint_0;
3267 end if;
3268
3269 -- Set component size up to match alignment if it
3270 -- would otherwise be less than the alignment. This
3271 -- deals with cases of types whose alignment exceeds
3272 -- their size (padded types).
3273
3274 if Csiz /= 0 then
3275 declare
3276 A : constant Uint := Alignment_In_Bits (Ctyp);
3277 begin
3278 if Csiz < A then
3279 Csiz := A;
3280 end if;
3281 end;
3282 end if;
3283 end if;
3284
3285 -- Case of component size that may result in packing
3286
3287 if 1 <= Csiz and then Csiz <= 64 then
3288 declare
3289 Ent : constant Entity_Id :=
3290 First_Subtype (E);
3291 Pack_Pragma : constant Node_Id :=
3292 Get_Rep_Pragma (Ent, Name_Pack);
3293 Comp_Size_C : constant Node_Id :=
3294 Get_Attribute_Definition_Clause
3295 (Ent, Attribute_Component_Size);
3296 begin
3297 -- Warn if we have pack and component size so that
3298 -- the pack is ignored.
3299
3300 -- Note: here we must check for the presence of a
3301 -- component size before checking for a Pack pragma
3302 -- to deal with the case where the array type is a
3303 -- derived type whose parent is currently private.
3304
3305 if Present (Comp_Size_C)
3306 and then Has_Pragma_Pack (Ent)
3307 and then Warn_On_Redundant_Constructs
3308 then
3309 Error_Msg_Sloc := Sloc (Comp_Size_C);
3310 Error_Msg_NE
3311 ("?pragma Pack for& ignored!",
3312 Pack_Pragma, Ent);
3313 Error_Msg_N
3314 ("\?explicit component size given#!",
3315 Pack_Pragma);
3316 Set_Is_Packed (Base_Type (Ent), False);
3317 Set_Is_Bit_Packed_Array (Base_Type (Ent), False);
3318 end if;
3319
3320 -- Set component size if not already set by a
3321 -- component size clause.
3322
3323 if not Present (Comp_Size_C) then
3324 Set_Component_Size (E, Csiz);
3325 end if;
3326
3327 -- Check for base type of 8, 16, 32 bits, where an
3328 -- unsigned subtype has a length one less than the
3329 -- base type (e.g. Natural subtype of Integer).
3330
3331 -- In such cases, if a component size was not set
3332 -- explicitly, then generate a warning.
3333
3334 if Has_Pragma_Pack (E)
3335 and then not Present (Comp_Size_C)
3336 and then
3337 (Csiz = 7 or else Csiz = 15 or else Csiz = 31)
3338 and then Esize (Base_Type (Ctyp)) = Csiz + 1
3339 then
3340 Error_Msg_Uint_1 := Csiz;
3341
3342 if Present (Pack_Pragma) then
3343 Error_Msg_N
3344 ("?pragma Pack causes component size "
3345 & "to be ^!", Pack_Pragma);
3346 Error_Msg_N
3347 ("\?use Component_Size to set "
3348 & "desired value!", Pack_Pragma);
3349 end if;
3350 end if;
3351
3352 -- Actual packing is not needed for 8, 16, 32, 64.
3353 -- Also not needed for 24 if alignment is 1.
3354
3355 if Csiz = 8
3356 or else Csiz = 16
3357 or else Csiz = 32
3358 or else Csiz = 64
3359 or else (Csiz = 24 and then Alignment (Ctyp) = 1)
3360 then
3361 -- Here the array was requested to be packed,
3362 -- but the packing request had no effect, so
3363 -- Is_Packed is reset.
3364
3365 -- Note: semantically this means that we lose
3366 -- track of the fact that a derived type
3367 -- inherited a pragma Pack that was non-
3368 -- effective, but that seems fine.
3369
3370 -- We regard a Pack pragma as a request to set
3371 -- a representation characteristic, and this
3372 -- request may be ignored.
3373
3374 Set_Is_Packed (Base_Type (E), False);
3375 Set_Is_Bit_Packed_Array (Base_Type (E), False);
3376
3377 if Known_Static_Esize (Component_Type (E))
3378 and then Esize (Component_Type (E)) = Csiz
3379 then
3380 Set_Has_Non_Standard_Rep
3381 (Base_Type (E), False);
3382 end if;
3383
3384 -- In all other cases, packing is indeed needed
3385
3386 else
3387 Set_Has_Non_Standard_Rep (Base_Type (E), True);
3388 Set_Is_Bit_Packed_Array (Base_Type (E), True);
3389 Set_Is_Packed (Base_Type (E), True);
3390 end if;
3391 end;
3392 end if;
3393 end;
3394
3395 -- Check for Atomic_Components or Aliased with unsuitable
3396 -- packing or explicit component size clause given.
3397
3398 if (Has_Atomic_Components (E)
3399 or else Has_Aliased_Components (E))
3400 and then (Has_Component_Size_Clause (E)
3401 or else Is_Packed (E))
3402 then
3403 Alias_Atomic_Check : declare
3404
3405 procedure Complain_CS (T : String);
3406 -- Outputs error messages for incorrect CS clause or
3407 -- pragma Pack for aliased or atomic components (T is
3408 -- "aliased" or "atomic");
3409
3410 -----------------
3411 -- Complain_CS --
3412 -----------------
3413
3414 procedure Complain_CS (T : String) is
3415 begin
3416 if Has_Component_Size_Clause (E) then
3417 Clause :=
3418 Get_Attribute_Definition_Clause
3419 (FS, Attribute_Component_Size);
3420
3421 if Known_Static_Esize (Ctyp) then
3422 Error_Msg_N
3423 ("incorrect component size for "
3424 & T & " components", Clause);
3425 Error_Msg_Uint_1 := Esize (Ctyp);
3426 Error_Msg_N
3427 ("\only allowed value is^", Clause);
3428
3429 else
3430 Error_Msg_N
3431 ("component size cannot be given for "
3432 & T & " components", Clause);
3433 end if;
3434
3435 else
3436 Error_Msg_N
3437 ("cannot pack " & T & " components",
3438 Get_Rep_Pragma (FS, Name_Pack));
3439 end if;
3440
3441 return;
3442 end Complain_CS;
3443
3444 -- Start of processing for Alias_Atomic_Check
3445
3446 begin
3447
3448 -- If object size of component type isn't known, we
3449 -- cannot be sure so we defer to the back end.
3450
3451 if not Known_Static_Esize (Ctyp) then
3452 null;
3453
3454 -- Case where component size has no effect. First
3455 -- check for object size of component type multiple
3456 -- of the storage unit size.
3457
3458 elsif Esize (Ctyp) mod System_Storage_Unit = 0
3459
3460 -- OK in both packing case and component size case
3461 -- if RM size is known and static and the same as
3462 -- the object size.
3463
3464 and then
3465 ((Known_Static_RM_Size (Ctyp)
3466 and then Esize (Ctyp) = RM_Size (Ctyp))
3467
3468 -- Or if we have an explicit component size
3469 -- clause and the component size and object size
3470 -- are equal.
3471
3472 or else
3473 (Has_Component_Size_Clause (E)
3474 and then Component_Size (E) = Esize (Ctyp)))
3475 then
3476 null;
3477
3478 elsif Has_Aliased_Components (E)
3479 or else Is_Aliased (Ctyp)
3480 then
3481 Complain_CS ("aliased");
3482
3483 elsif Has_Atomic_Components (E)
3484 or else Is_Atomic (Ctyp)
3485 then
3486 Complain_CS ("atomic");
3487 end if;
3488 end Alias_Atomic_Check;
3489 end if;
3490
3491 -- Warn for case of atomic type
3492
3493 Clause := Get_Rep_Pragma (FS, Name_Atomic);
3494
3495 if Present (Clause)
3496 and then not Addressable (Component_Size (FS))
3497 then
3498 Error_Msg_NE
3499 ("non-atomic components of type& may not be "
3500 & "accessible by separate tasks?", Clause, E);
3501
3502 if Has_Component_Size_Clause (E) then
3503 Error_Msg_Sloc :=
3504 Sloc
3505 (Get_Attribute_Definition_Clause
3506 (FS, Attribute_Component_Size));
3507 Error_Msg_N
3508 ("\because of component size clause#?",
3509 Clause);
3510
3511 elsif Has_Pragma_Pack (E) then
3512 Error_Msg_Sloc :=
3513 Sloc (Get_Rep_Pragma (FS, Name_Pack));
3514 Error_Msg_N
3515 ("\because of pragma Pack#?", Clause);
3516 end if;
3517 end if;
3518
3519 -- Processing that is done only for subtypes
3520
3521 else
3522 -- Acquire alignment from base type
3523
3524 if Unknown_Alignment (E) then
3525 Set_Alignment (E, Alignment (Base_Type (E)));
3526 Adjust_Esize_Alignment (E);
3527 end if;
3528 end if;
3529
3530 -- For bit-packed arrays, check the size
3531
3532 if Is_Bit_Packed_Array (E) and then Known_RM_Size (E) then
3533 declare
3534 SizC : constant Node_Id := Size_Clause (E);
3535
3536 Discard : Boolean;
3537 pragma Warnings (Off, Discard);
3538
3539 begin
3540 -- It is not clear if it is possible to have no size
3541 -- clause at this stage, but it is not worth worrying
3542 -- about. Post error on the entity name in the size
3543 -- clause if present, else on the type entity itself.
3544
3545 if Present (SizC) then
3546 Check_Size (Name (SizC), E, RM_Size (E), Discard);
3547 else
3548 Check_Size (E, E, RM_Size (E), Discard);
3549 end if;
3550 end;
3551 end if;
3552
3553 -- If any of the index types was an enumeration type with a
3554 -- non-standard rep clause, then we indicate that the array
3555 -- type is always packed (even if it is not bit packed).
3556
3557 if Non_Standard_Enum then
3558 Set_Has_Non_Standard_Rep (Base_Type (E));
3559 Set_Is_Packed (Base_Type (E));
3560 end if;
3561
3562 Set_Component_Alignment_If_Not_Set (E);
3563
3564 -- If the array is packed, we must create the packed array
3565 -- type to be used to actually implement the type. This is
3566 -- only needed for real array types (not for string literal
3567 -- types, since they are present only for the front end).
3568
3569 if Is_Packed (E)
3570 and then Ekind (E) /= E_String_Literal_Subtype
3571 then
3572 Create_Packed_Array_Type (E);
3573 Freeze_And_Append (Packed_Array_Type (E), N, Result);
3574
3575 -- Size information of packed array type is copied to the
3576 -- array type, since this is really the representation. But
3577 -- do not override explicit existing size values. If the
3578 -- ancestor subtype is constrained the packed_array_type
3579 -- will be inherited from it, but the size may have been
3580 -- provided already, and must not be overridden either.
3581
3582 if not Has_Size_Clause (E)
3583 and then
3584 (No (Ancestor_Subtype (E))
3585 or else not Has_Size_Clause (Ancestor_Subtype (E)))
3586 then
3587 Set_Esize (E, Esize (Packed_Array_Type (E)));
3588 Set_RM_Size (E, RM_Size (Packed_Array_Type (E)));
3589 end if;
3590
3591 if not Has_Alignment_Clause (E) then
3592 Set_Alignment (E, Alignment (Packed_Array_Type (E)));
3593 end if;
3594 end if;
3595
3596 -- For non-packed arrays set the alignment of the array to the
3597 -- alignment of the component type if it is unknown. Skip this
3598 -- in atomic case (atomic arrays may need larger alignments).
3599
3600 if not Is_Packed (E)
3601 and then Unknown_Alignment (E)
3602 and then Known_Alignment (Ctyp)
3603 and then Known_Static_Component_Size (E)
3604 and then Known_Static_Esize (Ctyp)
3605 and then Esize (Ctyp) = Component_Size (E)
3606 and then not Is_Atomic (E)
3607 then
3608 Set_Alignment (E, Alignment (Component_Type (E)));
3609 end if;
3610 end;
3611
3612 -- For a class-wide type, the corresponding specific type is
3613 -- frozen as well (RM 13.14(15))
3614
3615 elsif Is_Class_Wide_Type (E) then
3616 Freeze_And_Append (Root_Type (E), N, Result);
3617
3618 -- If the base type of the class-wide type is still incomplete,
3619 -- the class-wide remains unfrozen as well. This is legal when
3620 -- E is the formal of a primitive operation of some other type
3621 -- which is being frozen.
3622
3623 if not Is_Frozen (Root_Type (E)) then
3624 Set_Is_Frozen (E, False);
3625 return Result;
3626 end if;
3627
3628 -- If the Class_Wide_Type is an Itype (when type is the anonymous
3629 -- parent of a derived type) and it is a library-level entity,
3630 -- generate an itype reference for it. Otherwise, its first
3631 -- explicit reference may be in an inner scope, which will be
3632 -- rejected by the back-end.
3633
3634 if Is_Itype (E)
3635 and then Is_Compilation_Unit (Scope (E))
3636 then
3637 declare
3638 Ref : constant Node_Id := Make_Itype_Reference (Loc);
3639
3640 begin
3641 Set_Itype (Ref, E);
3642 Add_To_Result (Ref);
3643 end;
3644 end if;
3645
3646 -- The equivalent type associated with a class-wide subtype needs
3647 -- to be frozen to ensure that its layout is done.
3648
3649 if Ekind (E) = E_Class_Wide_Subtype
3650 and then Present (Equivalent_Type (E))
3651 then
3652 Freeze_And_Append (Equivalent_Type (E), N, Result);
3653 end if;
3654
3655 -- For a record (sub)type, freeze all the component types (RM
3656 -- 13.14(15). We test for E_Record_(sub)Type here, rather than using
3657 -- Is_Record_Type, because we don't want to attempt the freeze for
3658 -- the case of a private type with record extension (we will do that
3659 -- later when the full type is frozen).
3660
3661 elsif Ekind (E) = E_Record_Type
3662 or else Ekind (E) = E_Record_Subtype
3663 then
3664 Freeze_Record_Type (E);
3665
3666 -- For a concurrent type, freeze corresponding record type. This
3667 -- does not correspond to any specific rule in the RM, but the
3668 -- record type is essentially part of the concurrent type.
3669 -- Freeze as well all local entities. This includes record types
3670 -- created for entry parameter blocks, and whatever local entities
3671 -- may appear in the private part.
3672
3673 elsif Is_Concurrent_Type (E) then
3674 if Present (Corresponding_Record_Type (E)) then
3675 Freeze_And_Append
3676 (Corresponding_Record_Type (E), N, Result);
3677 end if;
3678
3679 Comp := First_Entity (E);
3680 while Present (Comp) loop
3681 if Is_Type (Comp) then
3682 Freeze_And_Append (Comp, N, Result);
3683
3684 elsif (Ekind (Comp)) /= E_Function then
3685 if Is_Itype (Etype (Comp))
3686 and then Underlying_Type (Scope (Etype (Comp))) = E
3687 then
3688 Undelay_Type (Etype (Comp));
3689 end if;
3690
3691 Freeze_And_Append (Etype (Comp), N, Result);
3692 end if;
3693
3694 Next_Entity (Comp);
3695 end loop;
3696
3697 -- Private types are required to point to the same freeze node as
3698 -- their corresponding full views. The freeze node itself has to
3699 -- point to the partial view of the entity (because from the partial
3700 -- view, we can retrieve the full view, but not the reverse).
3701 -- However, in order to freeze correctly, we need to freeze the full
3702 -- view. If we are freezing at the end of a scope (or within the
3703 -- scope of the private type), the partial and full views will have
3704 -- been swapped, the full view appears first in the entity chain and
3705 -- the swapping mechanism ensures that the pointers are properly set
3706 -- (on scope exit).
3707
3708 -- If we encounter the partial view before the full view (e.g. when
3709 -- freezing from another scope), we freeze the full view, and then
3710 -- set the pointers appropriately since we cannot rely on swapping to
3711 -- fix things up (subtypes in an outer scope might not get swapped).
3712
3713 elsif Is_Incomplete_Or_Private_Type (E)
3714 and then not Is_Generic_Type (E)
3715 then
3716 -- The construction of the dispatch table associated with library
3717 -- level tagged types forces freezing of all the primitives of the
3718 -- type, which may cause premature freezing of the partial view.
3719 -- For example:
3720
3721 -- package Pkg is
3722 -- type T is tagged private;
3723 -- type DT is new T with private;
3724 -- procedure Prim (X : in out T; Y : in out DT'Class);
3725 -- private
3726 -- type T is tagged null record;
3727 -- Obj : T;
3728 -- type DT is new T with null record;
3729 -- end;
3730
3731 -- In this case the type will be frozen later by the usual
3732 -- mechanism: an object declaration, an instantiation, or the
3733 -- end of a declarative part.
3734
3735 if Is_Library_Level_Tagged_Type (E)
3736 and then not Present (Full_View (E))
3737 then
3738 Set_Is_Frozen (E, False);
3739 return Result;
3740
3741 -- Case of full view present
3742
3743 elsif Present (Full_View (E)) then
3744
3745 -- If full view has already been frozen, then no further
3746 -- processing is required
3747
3748 if Is_Frozen (Full_View (E)) then
3749 Set_Has_Delayed_Freeze (E, False);
3750 Set_Freeze_Node (E, Empty);
3751 Check_Debug_Info_Needed (E);
3752
3753 -- Otherwise freeze full view and patch the pointers so that
3754 -- the freeze node will elaborate both views in the back-end.
3755
3756 else
3757 declare
3758 Full : constant Entity_Id := Full_View (E);
3759
3760 begin
3761 if Is_Private_Type (Full)
3762 and then Present (Underlying_Full_View (Full))
3763 then
3764 Freeze_And_Append
3765 (Underlying_Full_View (Full), N, Result);
3766 end if;
3767
3768 Freeze_And_Append (Full, N, Result);
3769
3770 if Has_Delayed_Freeze (E) then
3771 F_Node := Freeze_Node (Full);
3772
3773 if Present (F_Node) then
3774 Set_Freeze_Node (E, F_Node);
3775 Set_Entity (F_Node, E);
3776
3777 else
3778 -- {Incomplete,Private}_Subtypes with Full_Views
3779 -- constrained by discriminants.
3780
3781 Set_Has_Delayed_Freeze (E, False);
3782 Set_Freeze_Node (E, Empty);
3783 end if;
3784 end if;
3785 end;
3786
3787 Check_Debug_Info_Needed (E);
3788 end if;
3789
3790 -- AI-117 requires that the convention of a partial view be the
3791 -- same as the convention of the full view. Note that this is a
3792 -- recognized breach of privacy, but it's essential for logical
3793 -- consistency of representation, and the lack of a rule in
3794 -- RM95 was an oversight.
3795
3796 Set_Convention (E, Convention (Full_View (E)));
3797
3798 Set_Size_Known_At_Compile_Time (E,
3799 Size_Known_At_Compile_Time (Full_View (E)));
3800
3801 -- Size information is copied from the full view to the
3802 -- incomplete or private view for consistency.
3803
3804 -- We skip this is the full view is not a type. This is very
3805 -- strange of course, and can only happen as a result of
3806 -- certain illegalities, such as a premature attempt to derive
3807 -- from an incomplete type.
3808
3809 if Is_Type (Full_View (E)) then
3810 Set_Size_Info (E, Full_View (E));
3811 Set_RM_Size (E, RM_Size (Full_View (E)));
3812 end if;
3813
3814 return Result;
3815
3816 -- Case of no full view present. If entity is derived or subtype,
3817 -- it is safe to freeze, correctness depends on the frozen status
3818 -- of parent. Otherwise it is either premature usage, or a Taft
3819 -- amendment type, so diagnosis is at the point of use and the
3820 -- type might be frozen later.
3821
3822 elsif E /= Base_Type (E)
3823 or else Is_Derived_Type (E)
3824 then
3825 null;
3826
3827 else
3828 Set_Is_Frozen (E, False);
3829 return No_List;
3830 end if;
3831
3832 -- For access subprogram, freeze types of all formals, the return
3833 -- type was already frozen, since it is the Etype of the function.
3834 -- Formal types can be tagged Taft amendment types, but otherwise
3835 -- they cannot be incomplete.
3836
3837 elsif Ekind (E) = E_Subprogram_Type then
3838 Formal := First_Formal (E);
3839 while Present (Formal) loop
3840 if Ekind (Etype (Formal)) = E_Incomplete_Type
3841 and then No (Full_View (Etype (Formal)))
3842 and then not Is_Value_Type (Etype (Formal))
3843 then
3844 if Is_Tagged_Type (Etype (Formal)) then
3845 null;
3846
3847 -- AI05-151: Incomplete types are allowed in access to
3848 -- subprogram specifications.
3849
3850 elsif Ada_Version < Ada_2012 then
3851 Error_Msg_NE
3852 ("invalid use of incomplete type&", E, Etype (Formal));
3853 end if;
3854 end if;
3855
3856 Freeze_And_Append (Etype (Formal), N, Result);
3857 Next_Formal (Formal);
3858 end loop;
3859
3860 Freeze_Subprogram (E);
3861
3862 -- For access to a protected subprogram, freeze the equivalent type
3863 -- (however this is not set if we are not generating code or if this
3864 -- is an anonymous type used just for resolution).
3865
3866 elsif Is_Access_Protected_Subprogram_Type (E) then
3867 if Present (Equivalent_Type (E)) then
3868 Freeze_And_Append (Equivalent_Type (E), N, Result);
3869 end if;
3870 end if;
3871
3872 -- Generic types are never seen by the back-end, and are also not
3873 -- processed by the expander (since the expander is turned off for
3874 -- generic processing), so we never need freeze nodes for them.
3875
3876 if Is_Generic_Type (E) then
3877 return Result;
3878 end if;
3879
3880 -- Some special processing for non-generic types to complete
3881 -- representation details not known till the freeze point.
3882
3883 if Is_Fixed_Point_Type (E) then
3884 Freeze_Fixed_Point_Type (E);
3885
3886 -- Some error checks required for ordinary fixed-point type. Defer
3887 -- these till the freeze-point since we need the small and range
3888 -- values. We only do these checks for base types
3889
3890 if Is_Ordinary_Fixed_Point_Type (E) and then Is_Base_Type (E) then
3891 if Small_Value (E) < Ureal_2_M_80 then
3892 Error_Msg_Name_1 := Name_Small;
3893 Error_Msg_N
3894 ("`&''%` too small, minimum allowed is 2.0'*'*(-80)", E);
3895
3896 elsif Small_Value (E) > Ureal_2_80 then
3897 Error_Msg_Name_1 := Name_Small;
3898 Error_Msg_N
3899 ("`&''%` too large, maximum allowed is 2.0'*'*80", E);
3900 end if;
3901
3902 if Expr_Value_R (Type_Low_Bound (E)) < Ureal_M_10_36 then
3903 Error_Msg_Name_1 := Name_First;
3904 Error_Msg_N
3905 ("`&''%` too small, minimum allowed is -10.0'*'*36", E);
3906 end if;
3907
3908 if Expr_Value_R (Type_High_Bound (E)) > Ureal_10_36 then
3909 Error_Msg_Name_1 := Name_Last;
3910 Error_Msg_N
3911 ("`&''%` too large, maximum allowed is 10.0'*'*36", E);
3912 end if;
3913 end if;
3914
3915 elsif Is_Enumeration_Type (E) then
3916 Freeze_Enumeration_Type (E);
3917
3918 elsif Is_Integer_Type (E) then
3919 Adjust_Esize_For_Alignment (E);
3920
3921 if Is_Modular_Integer_Type (E)
3922 and then Warn_On_Suspicious_Modulus_Value
3923 then
3924 Check_Suspicious_Modulus (E);
3925 end if;
3926
3927 elsif Is_Access_Type (E) then
3928
3929 -- If a pragma Default_Storage_Pool applies, and this type has no
3930 -- Storage_Pool or Storage_Size clause (which must have occurred
3931 -- before the freezing point), then use the default. This applies
3932 -- only to base types.
3933
3934 if Present (Default_Pool)
3935 and then Is_Base_Type (E)
3936 and then not Has_Storage_Size_Clause (E)
3937 and then No (Associated_Storage_Pool (E))
3938 then
3939 -- Case of pragma Default_Storage_Pool (null)
3940
3941 if Nkind (Default_Pool) = N_Null then
3942 Set_No_Pool_Assigned (E);
3943
3944 -- Case of pragma Default_Storage_Pool (storage_pool_NAME)
3945
3946 else
3947 Set_Associated_Storage_Pool (E, Entity (Default_Pool));
3948 end if;
3949 end if;
3950
3951 -- Check restriction for standard storage pool
3952
3953 if No (Associated_Storage_Pool (E)) then
3954 Check_Restriction (No_Standard_Storage_Pools, E);
3955 end if;
3956
3957 -- Deal with error message for pure access type. This is not an
3958 -- error in Ada 2005 if there is no pool (see AI-366).
3959
3960 if Is_Pure_Unit_Access_Type (E)
3961 and then (Ada_Version < Ada_2005
3962 or else not No_Pool_Assigned (E))
3963 then
3964 Error_Msg_N ("named access type not allowed in pure unit", E);
3965
3966 if Ada_Version >= Ada_2005 then
3967 Error_Msg_N
3968 ("\would be legal if Storage_Size of 0 given?", E);
3969
3970 elsif No_Pool_Assigned (E) then
3971 Error_Msg_N
3972 ("\would be legal in Ada 2005?", E);
3973
3974 else
3975 Error_Msg_N
3976 ("\would be legal in Ada 2005 if "
3977 & "Storage_Size of 0 given?", E);
3978 end if;
3979 end if;
3980 end if;
3981
3982 -- Case of composite types
3983
3984 if Is_Composite_Type (E) then
3985
3986 -- AI-117 requires that all new primitives of a tagged type must
3987 -- inherit the convention of the full view of the type. Inherited
3988 -- and overriding operations are defined to inherit the convention
3989 -- of their parent or overridden subprogram (also specified in
3990 -- AI-117), which will have occurred earlier (in Derive_Subprogram
3991 -- and New_Overloaded_Entity). Here we set the convention of
3992 -- primitives that are still convention Ada, which will ensure
3993 -- that any new primitives inherit the type's convention. Class-
3994 -- wide types can have a foreign convention inherited from their
3995 -- specific type, but are excluded from this since they don't have
3996 -- any associated primitives.
3997
3998 if Is_Tagged_Type (E)
3999 and then not Is_Class_Wide_Type (E)
4000 and then Convention (E) /= Convention_Ada
4001 then
4002 declare
4003 Prim_List : constant Elist_Id := Primitive_Operations (E);
4004 Prim : Elmt_Id;
4005
4006 begin
4007 Prim := First_Elmt (Prim_List);
4008 while Present (Prim) loop
4009 if Convention (Node (Prim)) = Convention_Ada then
4010 Set_Convention (Node (Prim), Convention (E));
4011 end if;
4012
4013 Next_Elmt (Prim);
4014 end loop;
4015 end;
4016 end if;
4017 end if;
4018
4019 -- Now that all types from which E may depend are frozen, see if the
4020 -- size is known at compile time, if it must be unsigned, or if
4021 -- strict alignment is required
4022
4023 Check_Compile_Time_Size (E);
4024 Check_Unsigned_Type (E);
4025
4026 if Base_Type (E) = E then
4027 Check_Strict_Alignment (E);
4028 end if;
4029
4030 -- Do not allow a size clause for a type which does not have a size
4031 -- that is known at compile time
4032
4033 if Has_Size_Clause (E)
4034 and then not Size_Known_At_Compile_Time (E)
4035 then
4036 -- Suppress this message if errors posted on E, even if we are
4037 -- in all errors mode, since this is often a junk message
4038
4039 if not Error_Posted (E) then
4040 Error_Msg_N
4041 ("size clause not allowed for variable length type",
4042 Size_Clause (E));
4043 end if;
4044 end if;
4045
4046 -- Now we set/verify the representation information, in particular
4047 -- the size and alignment values. This processing is not required for
4048 -- generic types, since generic types do not play any part in code
4049 -- generation, and so the size and alignment values for such types
4050 -- are irrelevant.
4051
4052 if Is_Generic_Type (E) then
4053 return Result;
4054
4055 -- Otherwise we call the layout procedure
4056
4057 else
4058 Layout_Type (E);
4059 end if;
4060
4061 -- If the type has a Defaut_Value/Default_Component_Value aspect,
4062 -- this is where we analye the expression (after the type is frozen,
4063 -- since in the case of Default_Value, we are analyzing with the
4064 -- type itself, and we treat Default_Component_Value similarly for
4065 -- the sake of uniformity.
4066
4067 if Is_First_Subtype (E) and then Has_Default_Aspect (E) then
4068 declare
4069 Nam : Name_Id;
4070 Aspect : Node_Id;
4071 Exp : Node_Id;
4072 Typ : Entity_Id;
4073
4074 begin
4075 if Is_Scalar_Type (E) then
4076 Nam := Name_Default_Value;
4077 Typ := E;
4078 else
4079 Nam := Name_Default_Component_Value;
4080 Typ := Component_Type (E);
4081 end if;
4082
4083 Aspect := Get_Rep_Item_For_Entity (E, Nam);
4084 Exp := Expression (Aspect);
4085 Analyze_And_Resolve (Exp, Typ);
4086
4087 if Etype (Exp) /= Any_Type then
4088 if not Is_Static_Expression (Exp) then
4089 Error_Msg_Name_1 := Nam;
4090 Flag_Non_Static_Expr
4091 ("aspect% requires static expression", Exp);
4092 end if;
4093 end if;
4094 end;
4095 end if;
4096
4097 -- End of freeze processing for type entities
4098 end if;
4099
4100 -- Here is where we logically freeze the current entity. If it has a
4101 -- freeze node, then this is the point at which the freeze node is
4102 -- linked into the result list.
4103
4104 if Has_Delayed_Freeze (E) then
4105
4106 -- If a freeze node is already allocated, use it, otherwise allocate
4107 -- a new one. The preallocation happens in the case of anonymous base
4108 -- types, where we preallocate so that we can set First_Subtype_Link.
4109 -- Note that we reset the Sloc to the current freeze location.
4110
4111 if Present (Freeze_Node (E)) then
4112 F_Node := Freeze_Node (E);
4113 Set_Sloc (F_Node, Loc);
4114
4115 else
4116 F_Node := New_Node (N_Freeze_Entity, Loc);
4117 Set_Freeze_Node (E, F_Node);
4118 Set_Access_Types_To_Process (F_Node, No_Elist);
4119 Set_TSS_Elist (F_Node, No_Elist);
4120 Set_Actions (F_Node, No_List);
4121 end if;
4122
4123 Set_Entity (F_Node, E);
4124 Add_To_Result (F_Node);
4125
4126 -- A final pass over record types with discriminants. If the type
4127 -- has an incomplete declaration, there may be constrained access
4128 -- subtypes declared elsewhere, which do not depend on the discrimi-
4129 -- nants of the type, and which are used as component types (i.e.
4130 -- the full view is a recursive type). The designated types of these
4131 -- subtypes can only be elaborated after the type itself, and they
4132 -- need an itype reference.
4133
4134 if Ekind (E) = E_Record_Type
4135 and then Has_Discriminants (E)
4136 then
4137 declare
4138 Comp : Entity_Id;
4139 IR : Node_Id;
4140 Typ : Entity_Id;
4141
4142 begin
4143 Comp := First_Component (E);
4144 while Present (Comp) loop
4145 Typ := Etype (Comp);
4146
4147 if Ekind (Comp) = E_Component
4148 and then Is_Access_Type (Typ)
4149 and then Scope (Typ) /= E
4150 and then Base_Type (Designated_Type (Typ)) = E
4151 and then Is_Itype (Designated_Type (Typ))
4152 then
4153 IR := Make_Itype_Reference (Sloc (Comp));
4154 Set_Itype (IR, Designated_Type (Typ));
4155 Append (IR, Result);
4156 end if;
4157
4158 Next_Component (Comp);
4159 end loop;
4160 end;
4161 end if;
4162 end if;
4163
4164 -- When a type is frozen, the first subtype of the type is frozen as
4165 -- well (RM 13.14(15)). This has to be done after freezing the type,
4166 -- since obviously the first subtype depends on its own base type.
4167
4168 if Is_Type (E) then
4169 Freeze_And_Append (First_Subtype (E), N, Result);
4170
4171 -- If we just froze a tagged non-class wide record, then freeze the
4172 -- corresponding class-wide type. This must be done after the tagged
4173 -- type itself is frozen, because the class-wide type refers to the
4174 -- tagged type which generates the class.
4175
4176 if Is_Tagged_Type (E)
4177 and then not Is_Class_Wide_Type (E)
4178 and then Present (Class_Wide_Type (E))
4179 then
4180 Freeze_And_Append (Class_Wide_Type (E), N, Result);
4181 end if;
4182 end if;
4183
4184 Check_Debug_Info_Needed (E);
4185
4186 -- Special handling for subprograms
4187
4188 if Is_Subprogram (E) then
4189
4190 -- If subprogram has address clause then reset Is_Public flag, since
4191 -- we do not want the backend to generate external references.
4192
4193 if Present (Address_Clause (E))
4194 and then not Is_Library_Level_Entity (E)
4195 then
4196 Set_Is_Public (E, False);
4197
4198 -- If no address clause and not intrinsic, then for imported
4199 -- subprogram in main unit, generate descriptor if we are in
4200 -- Propagate_Exceptions mode.
4201
4202 -- This is very odd code, it makes a null result, why ???
4203
4204 elsif Propagate_Exceptions
4205 and then Is_Imported (E)
4206 and then not Is_Intrinsic_Subprogram (E)
4207 and then Convention (E) /= Convention_Stubbed
4208 then
4209 if Result = No_List then
4210 Result := Empty_List;
4211 end if;
4212 end if;
4213 end if;
4214
4215 return Result;
4216 end Freeze_Entity;
4217
4218 -----------------------------
4219 -- Freeze_Enumeration_Type --
4220 -----------------------------
4221
4222 procedure Freeze_Enumeration_Type (Typ : Entity_Id) is
4223 begin
4224 -- By default, if no size clause is present, an enumeration type with
4225 -- Convention C is assumed to interface to a C enum, and has integer
4226 -- size. This applies to types. For subtypes, verify that its base
4227 -- type has no size clause either.
4228
4229 if Has_Foreign_Convention (Typ)
4230 and then not Has_Size_Clause (Typ)
4231 and then not Has_Size_Clause (Base_Type (Typ))
4232 and then Esize (Typ) < Standard_Integer_Size
4233 then
4234 Init_Esize (Typ, Standard_Integer_Size);
4235
4236 else
4237 -- If the enumeration type interfaces to C, and it has a size clause
4238 -- that specifies less than int size, it warrants a warning. The
4239 -- user may intend the C type to be an enum or a char, so this is
4240 -- not by itself an error that the Ada compiler can detect, but it
4241 -- it is a worth a heads-up. For Boolean and Character types we
4242 -- assume that the programmer has the proper C type in mind.
4243
4244 if Convention (Typ) = Convention_C
4245 and then Has_Size_Clause (Typ)
4246 and then Esize (Typ) /= Esize (Standard_Integer)
4247 and then not Is_Boolean_Type (Typ)
4248 and then not Is_Character_Type (Typ)
4249 then
4250 Error_Msg_N
4251 ("C enum types have the size of a C int?", Size_Clause (Typ));
4252 end if;
4253
4254 Adjust_Esize_For_Alignment (Typ);
4255 end if;
4256 end Freeze_Enumeration_Type;
4257
4258 -----------------------
4259 -- Freeze_Expression --
4260 -----------------------
4261
4262 procedure Freeze_Expression (N : Node_Id) is
4263 In_Spec_Exp : constant Boolean := In_Spec_Expression;
4264 Typ : Entity_Id;
4265 Nam : Entity_Id;
4266 Desig_Typ : Entity_Id;
4267 P : Node_Id;
4268 Parent_P : Node_Id;
4269
4270 Freeze_Outside : Boolean := False;
4271 -- This flag is set true if the entity must be frozen outside the
4272 -- current subprogram. This happens in the case of expander generated
4273 -- subprograms (_Init_Proc, _Input, _Output, _Read, _Write) which do
4274 -- not freeze all entities like other bodies, but which nevertheless
4275 -- may reference entities that have to be frozen before the body and
4276 -- obviously cannot be frozen inside the body.
4277
4278 function In_Exp_Body (N : Node_Id) return Boolean;
4279 -- Given an N_Handled_Sequence_Of_Statements node N, determines whether
4280 -- it is the handled statement sequence of an expander-generated
4281 -- subprogram (init proc, stream subprogram, or renaming as body).
4282 -- If so, this is not a freezing context.
4283
4284 -----------------
4285 -- In_Exp_Body --
4286 -----------------
4287
4288 function In_Exp_Body (N : Node_Id) return Boolean is
4289 P : Node_Id;
4290 Id : Entity_Id;
4291
4292 begin
4293 if Nkind (N) = N_Subprogram_Body then
4294 P := N;
4295 else
4296 P := Parent (N);
4297 end if;
4298
4299 if Nkind (P) /= N_Subprogram_Body then
4300 return False;
4301
4302 else
4303 Id := Defining_Unit_Name (Specification (P));
4304
4305 if Nkind (Id) = N_Defining_Identifier
4306 and then (Is_Init_Proc (Id) or else
4307 Is_TSS (Id, TSS_Stream_Input) or else
4308 Is_TSS (Id, TSS_Stream_Output) or else
4309 Is_TSS (Id, TSS_Stream_Read) or else
4310 Is_TSS (Id, TSS_Stream_Write) or else
4311 Nkind (Original_Node (P)) =
4312 N_Subprogram_Renaming_Declaration)
4313 then
4314 return True;
4315 else
4316 return False;
4317 end if;
4318 end if;
4319 end In_Exp_Body;
4320
4321 -- Start of processing for Freeze_Expression
4322
4323 begin
4324 -- Immediate return if freezing is inhibited. This flag is set by the
4325 -- analyzer to stop freezing on generated expressions that would cause
4326 -- freezing if they were in the source program, but which are not
4327 -- supposed to freeze, since they are created.
4328
4329 if Must_Not_Freeze (N) then
4330 return;
4331 end if;
4332
4333 -- If expression is non-static, then it does not freeze in a default
4334 -- expression, see section "Handling of Default Expressions" in the
4335 -- spec of package Sem for further details. Note that we have to
4336 -- make sure that we actually have a real expression (if we have
4337 -- a subtype indication, we can't test Is_Static_Expression!)
4338
4339 if In_Spec_Exp
4340 and then Nkind (N) in N_Subexpr
4341 and then not Is_Static_Expression (N)
4342 then
4343 return;
4344 end if;
4345
4346 -- Freeze type of expression if not frozen already
4347
4348 Typ := Empty;
4349
4350 if Nkind (N) in N_Has_Etype then
4351 if not Is_Frozen (Etype (N)) then
4352 Typ := Etype (N);
4353
4354 -- Base type may be an derived numeric type that is frozen at
4355 -- the point of declaration, but first_subtype is still unfrozen.
4356
4357 elsif not Is_Frozen (First_Subtype (Etype (N))) then
4358 Typ := First_Subtype (Etype (N));
4359 end if;
4360 end if;
4361
4362 -- For entity name, freeze entity if not frozen already. A special
4363 -- exception occurs for an identifier that did not come from source.
4364 -- We don't let such identifiers freeze a non-internal entity, i.e.
4365 -- an entity that did come from source, since such an identifier was
4366 -- generated by the expander, and cannot have any semantic effect on
4367 -- the freezing semantics. For example, this stops the parameter of
4368 -- an initialization procedure from freezing the variable.
4369
4370 if Is_Entity_Name (N)
4371 and then not Is_Frozen (Entity (N))
4372 and then (Nkind (N) /= N_Identifier
4373 or else Comes_From_Source (N)
4374 or else not Comes_From_Source (Entity (N)))
4375 then
4376 Nam := Entity (N);
4377 else
4378 Nam := Empty;
4379 end if;
4380
4381 -- For an allocator freeze designated type if not frozen already
4382
4383 -- For an aggregate whose component type is an access type, freeze the
4384 -- designated type now, so that its freeze does not appear within the
4385 -- loop that might be created in the expansion of the aggregate. If the
4386 -- designated type is a private type without full view, the expression
4387 -- cannot contain an allocator, so the type is not frozen.
4388
4389 -- For a function, we freeze the entity when the subprogram declaration
4390 -- is frozen, but a function call may appear in an initialization proc.
4391 -- before the declaration is frozen. We need to generate the extra
4392 -- formals, if any, to ensure that the expansion of the call includes
4393 -- the proper actuals. This only applies to Ada subprograms, not to
4394 -- imported ones.
4395
4396 Desig_Typ := Empty;
4397
4398 case Nkind (N) is
4399 when N_Allocator =>
4400 Desig_Typ := Designated_Type (Etype (N));
4401
4402 when N_Aggregate =>
4403 if Is_Array_Type (Etype (N))
4404 and then Is_Access_Type (Component_Type (Etype (N)))
4405 then
4406 Desig_Typ := Designated_Type (Component_Type (Etype (N)));
4407 end if;
4408
4409 when N_Selected_Component |
4410 N_Indexed_Component |
4411 N_Slice =>
4412
4413 if Is_Access_Type (Etype (Prefix (N))) then
4414 Desig_Typ := Designated_Type (Etype (Prefix (N)));
4415 end if;
4416
4417 when N_Identifier =>
4418 if Present (Nam)
4419 and then Ekind (Nam) = E_Function
4420 and then Nkind (Parent (N)) = N_Function_Call
4421 and then Convention (Nam) = Convention_Ada
4422 then
4423 Create_Extra_Formals (Nam);
4424 end if;
4425
4426 when others =>
4427 null;
4428 end case;
4429
4430 if Desig_Typ /= Empty
4431 and then (Is_Frozen (Desig_Typ)
4432 or else (not Is_Fully_Defined (Desig_Typ)))
4433 then
4434 Desig_Typ := Empty;
4435 end if;
4436
4437 -- All done if nothing needs freezing
4438
4439 if No (Typ)
4440 and then No (Nam)
4441 and then No (Desig_Typ)
4442 then
4443 return;
4444 end if;
4445
4446 -- Loop for looking at the right place to insert the freeze nodes,
4447 -- exiting from the loop when it is appropriate to insert the freeze
4448 -- node before the current node P.
4449
4450 -- Also checks some special exceptions to the freezing rules. These
4451 -- cases result in a direct return, bypassing the freeze action.
4452
4453 P := N;
4454 loop
4455 Parent_P := Parent (P);
4456
4457 -- If we don't have a parent, then we are not in a well-formed tree.
4458 -- This is an unusual case, but there are some legitimate situations
4459 -- in which this occurs, notably when the expressions in the range of
4460 -- a type declaration are resolved. We simply ignore the freeze
4461 -- request in this case. Is this right ???
4462
4463 if No (Parent_P) then
4464 return;
4465 end if;
4466
4467 -- See if we have got to an appropriate point in the tree
4468
4469 case Nkind (Parent_P) is
4470
4471 -- A special test for the exception of (RM 13.14(8)) for the case
4472 -- of per-object expressions (RM 3.8(18)) occurring in component
4473 -- definition or a discrete subtype definition. Note that we test
4474 -- for a component declaration which includes both cases we are
4475 -- interested in, and furthermore the tree does not have explicit
4476 -- nodes for either of these two constructs.
4477
4478 when N_Component_Declaration =>
4479
4480 -- The case we want to test for here is an identifier that is
4481 -- a per-object expression, this is either a discriminant that
4482 -- appears in a context other than the component declaration
4483 -- or it is a reference to the type of the enclosing construct.
4484
4485 -- For either of these cases, we skip the freezing
4486
4487 if not In_Spec_Expression
4488 and then Nkind (N) = N_Identifier
4489 and then (Present (Entity (N)))
4490 then
4491 -- We recognize the discriminant case by just looking for
4492 -- a reference to a discriminant. It can only be one for
4493 -- the enclosing construct. Skip freezing in this case.
4494
4495 if Ekind (Entity (N)) = E_Discriminant then
4496 return;
4497
4498 -- For the case of a reference to the enclosing record,
4499 -- (or task or protected type), we look for a type that
4500 -- matches the current scope.
4501
4502 elsif Entity (N) = Current_Scope then
4503 return;
4504 end if;
4505 end if;
4506
4507 -- If we have an enumeration literal that appears as the choice in
4508 -- the aggregate of an enumeration representation clause, then
4509 -- freezing does not occur (RM 13.14(10)).
4510
4511 when N_Enumeration_Representation_Clause =>
4512
4513 -- The case we are looking for is an enumeration literal
4514
4515 if (Nkind (N) = N_Identifier or Nkind (N) = N_Character_Literal)
4516 and then Is_Enumeration_Type (Etype (N))
4517 then
4518 -- If enumeration literal appears directly as the choice,
4519 -- do not freeze (this is the normal non-overloaded case)
4520
4521 if Nkind (Parent (N)) = N_Component_Association
4522 and then First (Choices (Parent (N))) = N
4523 then
4524 return;
4525
4526 -- If enumeration literal appears as the name of function
4527 -- which is the choice, then also do not freeze. This
4528 -- happens in the overloaded literal case, where the
4529 -- enumeration literal is temporarily changed to a function
4530 -- call for overloading analysis purposes.
4531
4532 elsif Nkind (Parent (N)) = N_Function_Call
4533 and then
4534 Nkind (Parent (Parent (N))) = N_Component_Association
4535 and then
4536 First (Choices (Parent (Parent (N)))) = Parent (N)
4537 then
4538 return;
4539 end if;
4540 end if;
4541
4542 -- Normally if the parent is a handled sequence of statements,
4543 -- then the current node must be a statement, and that is an
4544 -- appropriate place to insert a freeze node.
4545
4546 when N_Handled_Sequence_Of_Statements =>
4547
4548 -- An exception occurs when the sequence of statements is for
4549 -- an expander generated body that did not do the usual freeze
4550 -- all operation. In this case we usually want to freeze
4551 -- outside this body, not inside it, and we skip past the
4552 -- subprogram body that we are inside.
4553
4554 if In_Exp_Body (Parent_P) then
4555
4556 -- However, we *do* want to freeze at this point if we have
4557 -- an entity to freeze, and that entity is declared *inside*
4558 -- the body of the expander generated procedure. This case
4559 -- is recognized by the scope of the type, which is either
4560 -- the spec for some enclosing body, or (in the case of
4561 -- init_procs, for which there are no separate specs) the
4562 -- current scope.
4563
4564 declare
4565 Subp : constant Node_Id := Parent (Parent_P);
4566 Cspc : Entity_Id;
4567
4568 begin
4569 if Nkind (Subp) = N_Subprogram_Body then
4570 Cspc := Corresponding_Spec (Subp);
4571
4572 if (Present (Typ) and then Scope (Typ) = Cspc)
4573 or else
4574 (Present (Nam) and then Scope (Nam) = Cspc)
4575 then
4576 exit;
4577
4578 elsif Present (Typ)
4579 and then Scope (Typ) = Current_Scope
4580 and then Current_Scope = Defining_Entity (Subp)
4581 then
4582 exit;
4583 end if;
4584 end if;
4585 end;
4586
4587 -- If not that exception to the exception, then this is
4588 -- where we delay the freeze till outside the body.
4589
4590 Parent_P := Parent (Parent_P);
4591 Freeze_Outside := True;
4592
4593 -- Here if normal case where we are in handled statement
4594 -- sequence and want to do the insertion right there.
4595
4596 else
4597 exit;
4598 end if;
4599
4600 -- If parent is a body or a spec or a block, then the current node
4601 -- is a statement or declaration and we can insert the freeze node
4602 -- before it.
4603
4604 when N_Block_Statement |
4605 N_Entry_Body |
4606 N_Package_Body |
4607 N_Package_Specification |
4608 N_Protected_Body |
4609 N_Subprogram_Body |
4610 N_Task_Body => exit;
4611
4612 -- The expander is allowed to define types in any statements list,
4613 -- so any of the following parent nodes also mark a freezing point
4614 -- if the actual node is in a list of statements or declarations.
4615
4616 when N_Abortable_Part |
4617 N_Accept_Alternative |
4618 N_And_Then |
4619 N_Case_Statement_Alternative |
4620 N_Compilation_Unit_Aux |
4621 N_Conditional_Entry_Call |
4622 N_Delay_Alternative |
4623 N_Elsif_Part |
4624 N_Entry_Call_Alternative |
4625 N_Exception_Handler |
4626 N_Extended_Return_Statement |
4627 N_Freeze_Entity |
4628 N_If_Statement |
4629 N_Or_Else |
4630 N_Selective_Accept |
4631 N_Triggering_Alternative =>
4632
4633 exit when Is_List_Member (P);
4634
4635 -- Note: The N_Loop_Statement is a special case. A type that
4636 -- appears in the source can never be frozen in a loop (this
4637 -- occurs only because of a loop expanded by the expander), so we
4638 -- keep on going. Otherwise we terminate the search. Same is true
4639 -- of any entity which comes from source. (if they have predefined
4640 -- type, that type does not appear to come from source, but the
4641 -- entity should not be frozen here).
4642
4643 when N_Loop_Statement =>
4644 exit when not Comes_From_Source (Etype (N))
4645 and then (No (Nam) or else not Comes_From_Source (Nam));
4646
4647 -- For all other cases, keep looking at parents
4648
4649 when others =>
4650 null;
4651 end case;
4652
4653 -- We fall through the case if we did not yet find the proper
4654 -- place in the free for inserting the freeze node, so climb!
4655
4656 P := Parent_P;
4657 end loop;
4658
4659 -- If the expression appears in a record or an initialization procedure,
4660 -- the freeze nodes are collected and attached to the current scope, to
4661 -- be inserted and analyzed on exit from the scope, to insure that
4662 -- generated entities appear in the correct scope. If the expression is
4663 -- a default for a discriminant specification, the scope is still void.
4664 -- The expression can also appear in the discriminant part of a private
4665 -- or concurrent type.
4666
4667 -- If the expression appears in a constrained subcomponent of an
4668 -- enclosing record declaration, the freeze nodes must be attached to
4669 -- the outer record type so they can eventually be placed in the
4670 -- enclosing declaration list.
4671
4672 -- The other case requiring this special handling is if we are in a
4673 -- default expression, since in that case we are about to freeze a
4674 -- static type, and the freeze scope needs to be the outer scope, not
4675 -- the scope of the subprogram with the default parameter.
4676
4677 -- For default expressions and other spec expressions in generic units,
4678 -- the Move_Freeze_Nodes mechanism (see sem_ch12.adb) takes care of
4679 -- placing them at the proper place, after the generic unit.
4680
4681 if (In_Spec_Exp and not Inside_A_Generic)
4682 or else Freeze_Outside
4683 or else (Is_Type (Current_Scope)
4684 and then (not Is_Concurrent_Type (Current_Scope)
4685 or else not Has_Completion (Current_Scope)))
4686 or else Ekind (Current_Scope) = E_Void
4687 then
4688 declare
4689 N : constant Node_Id := Current_Scope;
4690 Freeze_Nodes : List_Id := No_List;
4691 Pos : Int := Scope_Stack.Last;
4692
4693 begin
4694 if Present (Desig_Typ) then
4695 Freeze_And_Append (Desig_Typ, N, Freeze_Nodes);
4696 end if;
4697
4698 if Present (Typ) then
4699 Freeze_And_Append (Typ, N, Freeze_Nodes);
4700 end if;
4701
4702 if Present (Nam) then
4703 Freeze_And_Append (Nam, N, Freeze_Nodes);
4704 end if;
4705
4706 -- The current scope may be that of a constrained component of
4707 -- an enclosing record declaration, which is above the current
4708 -- scope in the scope stack.
4709 -- If the expression is within a top-level pragma, as for a pre-
4710 -- condition on a library-level subprogram, nothing to do.
4711
4712 if not Is_Compilation_Unit (Current_Scope)
4713 and then Is_Record_Type (Scope (Current_Scope))
4714 then
4715 Pos := Pos - 1;
4716 end if;
4717
4718 if Is_Non_Empty_List (Freeze_Nodes) then
4719 if No (Scope_Stack.Table (Pos).Pending_Freeze_Actions) then
4720 Scope_Stack.Table (Pos).Pending_Freeze_Actions :=
4721 Freeze_Nodes;
4722 else
4723 Append_List (Freeze_Nodes,
4724 Scope_Stack.Table (Pos).Pending_Freeze_Actions);
4725 end if;
4726 end if;
4727 end;
4728
4729 return;
4730 end if;
4731
4732 -- Now we have the right place to do the freezing. First, a special
4733 -- adjustment, if we are in spec-expression analysis mode, these freeze
4734 -- actions must not be thrown away (normally all inserted actions are
4735 -- thrown away in this mode. However, the freeze actions are from static
4736 -- expressions and one of the important reasons we are doing this
4737 -- special analysis is to get these freeze actions. Therefore we turn
4738 -- off the In_Spec_Expression mode to propagate these freeze actions.
4739 -- This also means they get properly analyzed and expanded.
4740
4741 In_Spec_Expression := False;
4742
4743 -- Freeze the designated type of an allocator (RM 13.14(13))
4744
4745 if Present (Desig_Typ) then
4746 Freeze_Before (P, Desig_Typ);
4747 end if;
4748
4749 -- Freeze type of expression (RM 13.14(10)). Note that we took care of
4750 -- the enumeration representation clause exception in the loop above.
4751
4752 if Present (Typ) then
4753 Freeze_Before (P, Typ);
4754 end if;
4755
4756 -- Freeze name if one is present (RM 13.14(11))
4757
4758 if Present (Nam) then
4759 Freeze_Before (P, Nam);
4760 end if;
4761
4762 -- Restore In_Spec_Expression flag
4763
4764 In_Spec_Expression := In_Spec_Exp;
4765 end Freeze_Expression;
4766
4767 -----------------------------
4768 -- Freeze_Fixed_Point_Type --
4769 -----------------------------
4770
4771 -- Certain fixed-point types and subtypes, including implicit base types
4772 -- and declared first subtypes, have not yet set up a range. This is
4773 -- because the range cannot be set until the Small and Size values are
4774 -- known, and these are not known till the type is frozen.
4775
4776 -- To signal this case, Scalar_Range contains an unanalyzed syntactic range
4777 -- whose bounds are unanalyzed real literals. This routine will recognize
4778 -- this case, and transform this range node into a properly typed range
4779 -- with properly analyzed and resolved values.
4780
4781 procedure Freeze_Fixed_Point_Type (Typ : Entity_Id) is
4782 Rng : constant Node_Id := Scalar_Range (Typ);
4783 Lo : constant Node_Id := Low_Bound (Rng);
4784 Hi : constant Node_Id := High_Bound (Rng);
4785 Btyp : constant Entity_Id := Base_Type (Typ);
4786 Brng : constant Node_Id := Scalar_Range (Btyp);
4787 BLo : constant Node_Id := Low_Bound (Brng);
4788 BHi : constant Node_Id := High_Bound (Brng);
4789 Small : constant Ureal := Small_Value (Typ);
4790 Loval : Ureal;
4791 Hival : Ureal;
4792 Atype : Entity_Id;
4793
4794 Actual_Size : Nat;
4795
4796 function Fsize (Lov, Hiv : Ureal) return Nat;
4797 -- Returns size of type with given bounds. Also leaves these
4798 -- bounds set as the current bounds of the Typ.
4799
4800 -----------
4801 -- Fsize --
4802 -----------
4803
4804 function Fsize (Lov, Hiv : Ureal) return Nat is
4805 begin
4806 Set_Realval (Lo, Lov);
4807 Set_Realval (Hi, Hiv);
4808 return Minimum_Size (Typ);
4809 end Fsize;
4810
4811 -- Start of processing for Freeze_Fixed_Point_Type
4812
4813 begin
4814 -- If Esize of a subtype has not previously been set, set it now
4815
4816 if Unknown_Esize (Typ) then
4817 Atype := Ancestor_Subtype (Typ);
4818
4819 if Present (Atype) then
4820 Set_Esize (Typ, Esize (Atype));
4821 else
4822 Set_Esize (Typ, Esize (Base_Type (Typ)));
4823 end if;
4824 end if;
4825
4826 -- Immediate return if the range is already analyzed. This means that
4827 -- the range is already set, and does not need to be computed by this
4828 -- routine.
4829
4830 if Analyzed (Rng) then
4831 return;
4832 end if;
4833
4834 -- Immediate return if either of the bounds raises Constraint_Error
4835
4836 if Raises_Constraint_Error (Lo)
4837 or else Raises_Constraint_Error (Hi)
4838 then
4839 return;
4840 end if;
4841
4842 Loval := Realval (Lo);
4843 Hival := Realval (Hi);
4844
4845 -- Ordinary fixed-point case
4846
4847 if Is_Ordinary_Fixed_Point_Type (Typ) then
4848
4849 -- For the ordinary fixed-point case, we are allowed to fudge the
4850 -- end-points up or down by small. Generally we prefer to fudge up,
4851 -- i.e. widen the bounds for non-model numbers so that the end points
4852 -- are included. However there are cases in which this cannot be
4853 -- done, and indeed cases in which we may need to narrow the bounds.
4854 -- The following circuit makes the decision.
4855
4856 -- Note: our terminology here is that Incl_EP means that the bounds
4857 -- are widened by Small if necessary to include the end points, and
4858 -- Excl_EP means that the bounds are narrowed by Small to exclude the
4859 -- end-points if this reduces the size.
4860
4861 -- Note that in the Incl case, all we care about is including the
4862 -- end-points. In the Excl case, we want to narrow the bounds as
4863 -- much as permitted by the RM, to give the smallest possible size.
4864
4865 Fudge : declare
4866 Loval_Incl_EP : Ureal;
4867 Hival_Incl_EP : Ureal;
4868
4869 Loval_Excl_EP : Ureal;
4870 Hival_Excl_EP : Ureal;
4871
4872 Size_Incl_EP : Nat;
4873 Size_Excl_EP : Nat;
4874
4875 Model_Num : Ureal;
4876 First_Subt : Entity_Id;
4877 Actual_Lo : Ureal;
4878 Actual_Hi : Ureal;
4879
4880 begin
4881 -- First step. Base types are required to be symmetrical. Right
4882 -- now, the base type range is a copy of the first subtype range.
4883 -- This will be corrected before we are done, but right away we
4884 -- need to deal with the case where both bounds are non-negative.
4885 -- In this case, we set the low bound to the negative of the high
4886 -- bound, to make sure that the size is computed to include the
4887 -- required sign. Note that we do not need to worry about the
4888 -- case of both bounds negative, because the sign will be dealt
4889 -- with anyway. Furthermore we can't just go making such a bound
4890 -- symmetrical, since in a twos-complement system, there is an
4891 -- extra negative value which could not be accommodated on the
4892 -- positive side.
4893
4894 if Typ = Btyp
4895 and then not UR_Is_Negative (Loval)
4896 and then Hival > Loval
4897 then
4898 Loval := -Hival;
4899 Set_Realval (Lo, Loval);
4900 end if;
4901
4902 -- Compute the fudged bounds. If the number is a model number,
4903 -- then we do nothing to include it, but we are allowed to backoff
4904 -- to the next adjacent model number when we exclude it. If it is
4905 -- not a model number then we straddle the two values with the
4906 -- model numbers on either side.
4907
4908 Model_Num := UR_Trunc (Loval / Small) * Small;
4909
4910 if Loval = Model_Num then
4911 Loval_Incl_EP := Model_Num;
4912 else
4913 Loval_Incl_EP := Model_Num - Small;
4914 end if;
4915
4916 -- The low value excluding the end point is Small greater, but
4917 -- we do not do this exclusion if the low value is positive,
4918 -- since it can't help the size and could actually hurt by
4919 -- crossing the high bound.
4920
4921 if UR_Is_Negative (Loval_Incl_EP) then
4922 Loval_Excl_EP := Loval_Incl_EP + Small;
4923
4924 -- If the value went from negative to zero, then we have the
4925 -- case where Loval_Incl_EP is the model number just below
4926 -- zero, so we want to stick to the negative value for the
4927 -- base type to maintain the condition that the size will
4928 -- include signed values.
4929
4930 if Typ = Btyp
4931 and then UR_Is_Zero (Loval_Excl_EP)
4932 then
4933 Loval_Excl_EP := Loval_Incl_EP;
4934 end if;
4935
4936 else
4937 Loval_Excl_EP := Loval_Incl_EP;
4938 end if;
4939
4940 -- Similar processing for upper bound and high value
4941
4942 Model_Num := UR_Trunc (Hival / Small) * Small;
4943
4944 if Hival = Model_Num then
4945 Hival_Incl_EP := Model_Num;
4946 else
4947 Hival_Incl_EP := Model_Num + Small;
4948 end if;
4949
4950 if UR_Is_Positive (Hival_Incl_EP) then
4951 Hival_Excl_EP := Hival_Incl_EP - Small;
4952 else
4953 Hival_Excl_EP := Hival_Incl_EP;
4954 end if;
4955
4956 -- One further adjustment is needed. In the case of subtypes, we
4957 -- cannot go outside the range of the base type, or we get
4958 -- peculiarities, and the base type range is already set. This
4959 -- only applies to the Incl values, since clearly the Excl values
4960 -- are already as restricted as they are allowed to be.
4961
4962 if Typ /= Btyp then
4963 Loval_Incl_EP := UR_Max (Loval_Incl_EP, Realval (BLo));
4964 Hival_Incl_EP := UR_Min (Hival_Incl_EP, Realval (BHi));
4965 end if;
4966
4967 -- Get size including and excluding end points
4968
4969 Size_Incl_EP := Fsize (Loval_Incl_EP, Hival_Incl_EP);
4970 Size_Excl_EP := Fsize (Loval_Excl_EP, Hival_Excl_EP);
4971
4972 -- No need to exclude end-points if it does not reduce size
4973
4974 if Fsize (Loval_Incl_EP, Hival_Excl_EP) = Size_Excl_EP then
4975 Loval_Excl_EP := Loval_Incl_EP;
4976 end if;
4977
4978 if Fsize (Loval_Excl_EP, Hival_Incl_EP) = Size_Excl_EP then
4979 Hival_Excl_EP := Hival_Incl_EP;
4980 end if;
4981
4982 -- Now we set the actual size to be used. We want to use the
4983 -- bounds fudged up to include the end-points but only if this
4984 -- can be done without violating a specifically given size
4985 -- size clause or causing an unacceptable increase in size.
4986
4987 -- Case of size clause given
4988
4989 if Has_Size_Clause (Typ) then
4990
4991 -- Use the inclusive size only if it is consistent with
4992 -- the explicitly specified size.
4993
4994 if Size_Incl_EP <= RM_Size (Typ) then
4995 Actual_Lo := Loval_Incl_EP;
4996 Actual_Hi := Hival_Incl_EP;
4997 Actual_Size := Size_Incl_EP;
4998
4999 -- If the inclusive size is too large, we try excluding
5000 -- the end-points (will be caught later if does not work).
5001
5002 else
5003 Actual_Lo := Loval_Excl_EP;
5004 Actual_Hi := Hival_Excl_EP;
5005 Actual_Size := Size_Excl_EP;
5006 end if;
5007
5008 -- Case of size clause not given
5009
5010 else
5011 -- If we have a base type whose corresponding first subtype
5012 -- has an explicit size that is large enough to include our
5013 -- end-points, then do so. There is no point in working hard
5014 -- to get a base type whose size is smaller than the specified
5015 -- size of the first subtype.
5016
5017 First_Subt := First_Subtype (Typ);
5018
5019 if Has_Size_Clause (First_Subt)
5020 and then Size_Incl_EP <= Esize (First_Subt)
5021 then
5022 Actual_Size := Size_Incl_EP;
5023 Actual_Lo := Loval_Incl_EP;
5024 Actual_Hi := Hival_Incl_EP;
5025
5026 -- If excluding the end-points makes the size smaller and
5027 -- results in a size of 8,16,32,64, then we take the smaller
5028 -- size. For the 64 case, this is compulsory. For the other
5029 -- cases, it seems reasonable. We like to include end points
5030 -- if we can, but not at the expense of moving to the next
5031 -- natural boundary of size.
5032
5033 elsif Size_Incl_EP /= Size_Excl_EP
5034 and then Addressable (Size_Excl_EP)
5035 then
5036 Actual_Size := Size_Excl_EP;
5037 Actual_Lo := Loval_Excl_EP;
5038 Actual_Hi := Hival_Excl_EP;
5039
5040 -- Otherwise we can definitely include the end points
5041
5042 else
5043 Actual_Size := Size_Incl_EP;
5044 Actual_Lo := Loval_Incl_EP;
5045 Actual_Hi := Hival_Incl_EP;
5046 end if;
5047
5048 -- One pathological case: normally we never fudge a low bound
5049 -- down, since it would seem to increase the size (if it has
5050 -- any effect), but for ranges containing single value, or no
5051 -- values, the high bound can be small too large. Consider:
5052
5053 -- type t is delta 2.0**(-14)
5054 -- range 131072.0 .. 0;
5055
5056 -- That lower bound is *just* outside the range of 32 bits, and
5057 -- does need fudging down in this case. Note that the bounds
5058 -- will always have crossed here, since the high bound will be
5059 -- fudged down if necessary, as in the case of:
5060
5061 -- type t is delta 2.0**(-14)
5062 -- range 131072.0 .. 131072.0;
5063
5064 -- So we detect the situation by looking for crossed bounds,
5065 -- and if the bounds are crossed, and the low bound is greater
5066 -- than zero, we will always back it off by small, since this
5067 -- is completely harmless.
5068
5069 if Actual_Lo > Actual_Hi then
5070 if UR_Is_Positive (Actual_Lo) then
5071 Actual_Lo := Loval_Incl_EP - Small;
5072 Actual_Size := Fsize (Actual_Lo, Actual_Hi);
5073
5074 -- And of course, we need to do exactly the same parallel
5075 -- fudge for flat ranges in the negative region.
5076
5077 elsif UR_Is_Negative (Actual_Hi) then
5078 Actual_Hi := Hival_Incl_EP + Small;
5079 Actual_Size := Fsize (Actual_Lo, Actual_Hi);
5080 end if;
5081 end if;
5082 end if;
5083
5084 Set_Realval (Lo, Actual_Lo);
5085 Set_Realval (Hi, Actual_Hi);
5086 end Fudge;
5087
5088 -- For the decimal case, none of this fudging is required, since there
5089 -- are no end-point problems in the decimal case (the end-points are
5090 -- always included).
5091
5092 else
5093 Actual_Size := Fsize (Loval, Hival);
5094 end if;
5095
5096 -- At this stage, the actual size has been calculated and the proper
5097 -- required bounds are stored in the low and high bounds.
5098
5099 if Actual_Size > 64 then
5100 Error_Msg_Uint_1 := UI_From_Int (Actual_Size);
5101 Error_Msg_N
5102 ("size required (^) for type& too large, maximum allowed is 64",
5103 Typ);
5104 Actual_Size := 64;
5105 end if;
5106
5107 -- Check size against explicit given size
5108
5109 if Has_Size_Clause (Typ) then
5110 if Actual_Size > RM_Size (Typ) then
5111 Error_Msg_Uint_1 := RM_Size (Typ);
5112 Error_Msg_Uint_2 := UI_From_Int (Actual_Size);
5113 Error_Msg_NE
5114 ("size given (^) for type& too small, minimum allowed is ^",
5115 Size_Clause (Typ), Typ);
5116
5117 else
5118 Actual_Size := UI_To_Int (Esize (Typ));
5119 end if;
5120
5121 -- Increase size to next natural boundary if no size clause given
5122
5123 else
5124 if Actual_Size <= 8 then
5125 Actual_Size := 8;
5126 elsif Actual_Size <= 16 then
5127 Actual_Size := 16;
5128 elsif Actual_Size <= 32 then
5129 Actual_Size := 32;
5130 else
5131 Actual_Size := 64;
5132 end if;
5133
5134 Init_Esize (Typ, Actual_Size);
5135 Adjust_Esize_For_Alignment (Typ);
5136 end if;
5137
5138 -- If we have a base type, then expand the bounds so that they extend to
5139 -- the full width of the allocated size in bits, to avoid junk range
5140 -- checks on intermediate computations.
5141
5142 if Base_Type (Typ) = Typ then
5143 Set_Realval (Lo, -(Small * (Uint_2 ** (Actual_Size - 1))));
5144 Set_Realval (Hi, (Small * (Uint_2 ** (Actual_Size - 1) - 1)));
5145 end if;
5146
5147 -- Final step is to reanalyze the bounds using the proper type
5148 -- and set the Corresponding_Integer_Value fields of the literals.
5149
5150 Set_Etype (Lo, Empty);
5151 Set_Analyzed (Lo, False);
5152 Analyze (Lo);
5153
5154 -- Resolve with universal fixed if the base type, and the base type if
5155 -- it is a subtype. Note we can't resolve the base type with itself,
5156 -- that would be a reference before definition.
5157
5158 if Typ = Btyp then
5159 Resolve (Lo, Universal_Fixed);
5160 else
5161 Resolve (Lo, Btyp);
5162 end if;
5163
5164 -- Set corresponding integer value for bound
5165
5166 Set_Corresponding_Integer_Value
5167 (Lo, UR_To_Uint (Realval (Lo) / Small));
5168
5169 -- Similar processing for high bound
5170
5171 Set_Etype (Hi, Empty);
5172 Set_Analyzed (Hi, False);
5173 Analyze (Hi);
5174
5175 if Typ = Btyp then
5176 Resolve (Hi, Universal_Fixed);
5177 else
5178 Resolve (Hi, Btyp);
5179 end if;
5180
5181 Set_Corresponding_Integer_Value
5182 (Hi, UR_To_Uint (Realval (Hi) / Small));
5183
5184 -- Set type of range to correspond to bounds
5185
5186 Set_Etype (Rng, Etype (Lo));
5187
5188 -- Set Esize to calculated size if not set already
5189
5190 if Unknown_Esize (Typ) then
5191 Init_Esize (Typ, Actual_Size);
5192 end if;
5193
5194 -- Set RM_Size if not already set. If already set, check value
5195
5196 declare
5197 Minsiz : constant Uint := UI_From_Int (Minimum_Size (Typ));
5198
5199 begin
5200 if RM_Size (Typ) /= Uint_0 then
5201 if RM_Size (Typ) < Minsiz then
5202 Error_Msg_Uint_1 := RM_Size (Typ);
5203 Error_Msg_Uint_2 := Minsiz;
5204 Error_Msg_NE
5205 ("size given (^) for type& too small, minimum allowed is ^",
5206 Size_Clause (Typ), Typ);
5207 end if;
5208
5209 else
5210 Set_RM_Size (Typ, Minsiz);
5211 end if;
5212 end;
5213 end Freeze_Fixed_Point_Type;
5214
5215 ------------------
5216 -- Freeze_Itype --
5217 ------------------
5218
5219 procedure Freeze_Itype (T : Entity_Id; N : Node_Id) is
5220 L : List_Id;
5221
5222 begin
5223 Set_Has_Delayed_Freeze (T);
5224 L := Freeze_Entity (T, N);
5225
5226 if Is_Non_Empty_List (L) then
5227 Insert_Actions (N, L);
5228 end if;
5229 end Freeze_Itype;
5230
5231 --------------------------
5232 -- Freeze_Static_Object --
5233 --------------------------
5234
5235 procedure Freeze_Static_Object (E : Entity_Id) is
5236
5237 Cannot_Be_Static : exception;
5238 -- Exception raised if the type of a static object cannot be made
5239 -- static. This happens if the type depends on non-global objects.
5240
5241 procedure Ensure_Expression_Is_SA (N : Node_Id);
5242 -- Called to ensure that an expression used as part of a type definition
5243 -- is statically allocatable, which means that the expression type is
5244 -- statically allocatable, and the expression is either static, or a
5245 -- reference to a library level constant.
5246
5247 procedure Ensure_Type_Is_SA (Typ : Entity_Id);
5248 -- Called to mark a type as static, checking that it is possible
5249 -- to set the type as static. If it is not possible, then the
5250 -- exception Cannot_Be_Static is raised.
5251
5252 -----------------------------
5253 -- Ensure_Expression_Is_SA --
5254 -----------------------------
5255
5256 procedure Ensure_Expression_Is_SA (N : Node_Id) is
5257 Ent : Entity_Id;
5258
5259 begin
5260 Ensure_Type_Is_SA (Etype (N));
5261
5262 if Is_Static_Expression (N) then
5263 return;
5264
5265 elsif Nkind (N) = N_Identifier then
5266 Ent := Entity (N);
5267
5268 if Present (Ent)
5269 and then Ekind (Ent) = E_Constant
5270 and then Is_Library_Level_Entity (Ent)
5271 then
5272 return;
5273 end if;
5274 end if;
5275
5276 raise Cannot_Be_Static;
5277 end Ensure_Expression_Is_SA;
5278
5279 -----------------------
5280 -- Ensure_Type_Is_SA --
5281 -----------------------
5282
5283 procedure Ensure_Type_Is_SA (Typ : Entity_Id) is
5284 N : Node_Id;
5285 C : Entity_Id;
5286
5287 begin
5288 -- If type is library level, we are all set
5289
5290 if Is_Library_Level_Entity (Typ) then
5291 return;
5292 end if;
5293
5294 -- We are also OK if the type already marked as statically allocated,
5295 -- which means we processed it before.
5296
5297 if Is_Statically_Allocated (Typ) then
5298 return;
5299 end if;
5300
5301 -- Mark type as statically allocated
5302
5303 Set_Is_Statically_Allocated (Typ);
5304
5305 -- Check that it is safe to statically allocate this type
5306
5307 if Is_Scalar_Type (Typ) or else Is_Real_Type (Typ) then
5308 Ensure_Expression_Is_SA (Type_Low_Bound (Typ));
5309 Ensure_Expression_Is_SA (Type_High_Bound (Typ));
5310
5311 elsif Is_Array_Type (Typ) then
5312 N := First_Index (Typ);
5313 while Present (N) loop
5314 Ensure_Type_Is_SA (Etype (N));
5315 Next_Index (N);
5316 end loop;
5317
5318 Ensure_Type_Is_SA (Component_Type (Typ));
5319
5320 elsif Is_Access_Type (Typ) then
5321 if Ekind (Designated_Type (Typ)) = E_Subprogram_Type then
5322
5323 declare
5324 F : Entity_Id;
5325 T : constant Entity_Id := Etype (Designated_Type (Typ));
5326
5327 begin
5328 if T /= Standard_Void_Type then
5329 Ensure_Type_Is_SA (T);
5330 end if;
5331
5332 F := First_Formal (Designated_Type (Typ));
5333 while Present (F) loop
5334 Ensure_Type_Is_SA (Etype (F));
5335 Next_Formal (F);
5336 end loop;
5337 end;
5338
5339 else
5340 Ensure_Type_Is_SA (Designated_Type (Typ));
5341 end if;
5342
5343 elsif Is_Record_Type (Typ) then
5344 C := First_Entity (Typ);
5345 while Present (C) loop
5346 if Ekind (C) = E_Discriminant
5347 or else Ekind (C) = E_Component
5348 then
5349 Ensure_Type_Is_SA (Etype (C));
5350
5351 elsif Is_Type (C) then
5352 Ensure_Type_Is_SA (C);
5353 end if;
5354
5355 Next_Entity (C);
5356 end loop;
5357
5358 elsif Ekind (Typ) = E_Subprogram_Type then
5359 Ensure_Type_Is_SA (Etype (Typ));
5360
5361 C := First_Formal (Typ);
5362 while Present (C) loop
5363 Ensure_Type_Is_SA (Etype (C));
5364 Next_Formal (C);
5365 end loop;
5366
5367 else
5368 raise Cannot_Be_Static;
5369 end if;
5370 end Ensure_Type_Is_SA;
5371
5372 -- Start of processing for Freeze_Static_Object
5373
5374 begin
5375 Ensure_Type_Is_SA (Etype (E));
5376
5377 exception
5378 when Cannot_Be_Static =>
5379
5380 -- If the object that cannot be static is imported or exported, then
5381 -- issue an error message saying that this object cannot be imported
5382 -- or exported. If it has an address clause it is an overlay in the
5383 -- current partition and the static requirement is not relevant.
5384 -- Do not issue any error message when ignoring rep clauses.
5385
5386 if Ignore_Rep_Clauses then
5387 null;
5388
5389 elsif Is_Imported (E) then
5390 if No (Address_Clause (E)) then
5391 Error_Msg_N
5392 ("& cannot be imported (local type is not constant)", E);
5393 end if;
5394
5395 -- Otherwise must be exported, something is wrong if compiler
5396 -- is marking something as statically allocated which cannot be).
5397
5398 else pragma Assert (Is_Exported (E));
5399 Error_Msg_N
5400 ("& cannot be exported (local type is not constant)", E);
5401 end if;
5402 end Freeze_Static_Object;
5403
5404 -----------------------
5405 -- Freeze_Subprogram --
5406 -----------------------
5407
5408 procedure Freeze_Subprogram (E : Entity_Id) is
5409 Retype : Entity_Id;
5410 F : Entity_Id;
5411
5412 begin
5413 -- Subprogram may not have an address clause unless it is imported
5414
5415 if Present (Address_Clause (E)) then
5416 if not Is_Imported (E) then
5417 Error_Msg_N
5418 ("address clause can only be given " &
5419 "for imported subprogram",
5420 Name (Address_Clause (E)));
5421 end if;
5422 end if;
5423
5424 -- Reset the Pure indication on an imported subprogram unless an
5425 -- explicit Pure_Function pragma was present. We do this because
5426 -- otherwise it is an insidious error to call a non-pure function from
5427 -- pure unit and have calls mysteriously optimized away. What happens
5428 -- here is that the Import can bypass the normal check to ensure that
5429 -- pure units call only pure subprograms.
5430
5431 if Is_Imported (E)
5432 and then Is_Pure (E)
5433 and then not Has_Pragma_Pure_Function (E)
5434 then
5435 Set_Is_Pure (E, False);
5436 end if;
5437
5438 -- For non-foreign convention subprograms, this is where we create
5439 -- the extra formals (for accessibility level and constrained bit
5440 -- information). We delay this till the freeze point precisely so
5441 -- that we know the convention!
5442
5443 if not Has_Foreign_Convention (E) then
5444 Create_Extra_Formals (E);
5445 Set_Mechanisms (E);
5446
5447 -- If this is convention Ada and a Valued_Procedure, that's odd
5448
5449 if Ekind (E) = E_Procedure
5450 and then Is_Valued_Procedure (E)
5451 and then Convention (E) = Convention_Ada
5452 and then Warn_On_Export_Import
5453 then
5454 Error_Msg_N
5455 ("?Valued_Procedure has no effect for convention Ada", E);
5456 Set_Is_Valued_Procedure (E, False);
5457 end if;
5458
5459 -- Case of foreign convention
5460
5461 else
5462 Set_Mechanisms (E);
5463
5464 -- For foreign conventions, warn about return of an
5465 -- unconstrained array.
5466
5467 -- Note: we *do* allow a return by descriptor for the VMS case,
5468 -- though here there is probably more to be done ???
5469
5470 if Ekind (E) = E_Function then
5471 Retype := Underlying_Type (Etype (E));
5472
5473 -- If no return type, probably some other error, e.g. a
5474 -- missing full declaration, so ignore.
5475
5476 if No (Retype) then
5477 null;
5478
5479 -- If the return type is generic, we have emitted a warning
5480 -- earlier on, and there is nothing else to check here. Specific
5481 -- instantiations may lead to erroneous behavior.
5482
5483 elsif Is_Generic_Type (Etype (E)) then
5484 null;
5485
5486 -- Display warning if returning unconstrained array
5487
5488 elsif Is_Array_Type (Retype)
5489 and then not Is_Constrained (Retype)
5490
5491 -- Exclude cases where descriptor mechanism is set, since the
5492 -- VMS descriptor mechanisms allow such unconstrained returns.
5493
5494 and then Mechanism (E) not in Descriptor_Codes
5495
5496 -- Check appropriate warning is enabled (should we check for
5497 -- Warnings (Off) on specific entities here, probably so???)
5498
5499 and then Warn_On_Export_Import
5500
5501 -- Exclude the VM case, since return of unconstrained arrays
5502 -- is properly handled in both the JVM and .NET cases.
5503
5504 and then VM_Target = No_VM
5505 then
5506 Error_Msg_N
5507 ("?foreign convention function& should not return " &
5508 "unconstrained array", E);
5509 return;
5510 end if;
5511 end if;
5512
5513 -- If any of the formals for an exported foreign convention
5514 -- subprogram have defaults, then emit an appropriate warning since
5515 -- this is odd (default cannot be used from non-Ada code)
5516
5517 if Is_Exported (E) then
5518 F := First_Formal (E);
5519 while Present (F) loop
5520 if Warn_On_Export_Import
5521 and then Present (Default_Value (F))
5522 then
5523 Error_Msg_N
5524 ("?parameter cannot be defaulted in non-Ada call",
5525 Default_Value (F));
5526 end if;
5527
5528 Next_Formal (F);
5529 end loop;
5530 end if;
5531 end if;
5532
5533 -- For VMS, descriptor mechanisms for parameters are allowed only for
5534 -- imported/exported subprograms. Moreover, the NCA descriptor is not
5535 -- allowed for parameters of exported subprograms.
5536
5537 if OpenVMS_On_Target then
5538 if Is_Exported (E) then
5539 F := First_Formal (E);
5540 while Present (F) loop
5541 if Mechanism (F) = By_Descriptor_NCA then
5542 Error_Msg_N
5543 ("'N'C'A' descriptor for parameter not permitted", F);
5544 Error_Msg_N
5545 ("\can only be used for imported subprogram", F);
5546 end if;
5547
5548 Next_Formal (F);
5549 end loop;
5550
5551 elsif not Is_Imported (E) then
5552 F := First_Formal (E);
5553 while Present (F) loop
5554 if Mechanism (F) in Descriptor_Codes then
5555 Error_Msg_N
5556 ("descriptor mechanism for parameter not permitted", F);
5557 Error_Msg_N
5558 ("\can only be used for imported/exported subprogram", F);
5559 end if;
5560
5561 Next_Formal (F);
5562 end loop;
5563 end if;
5564 end if;
5565
5566 -- Pragma Inline_Always is disallowed for dispatching subprograms
5567 -- because the address of such subprograms is saved in the dispatch
5568 -- table to support dispatching calls, and dispatching calls cannot
5569 -- be inlined. This is consistent with the restriction against using
5570 -- 'Access or 'Address on an Inline_Always subprogram.
5571
5572 if Is_Dispatching_Operation (E)
5573 and then Has_Pragma_Inline_Always (E)
5574 then
5575 Error_Msg_N
5576 ("pragma Inline_Always not allowed for dispatching subprograms", E);
5577 end if;
5578
5579 -- Because of the implicit representation of inherited predefined
5580 -- operators in the front-end, the overriding status of the operation
5581 -- may be affected when a full view of a type is analyzed, and this is
5582 -- not captured by the analysis of the corresponding type declaration.
5583 -- Therefore the correctness of a not-overriding indicator must be
5584 -- rechecked when the subprogram is frozen.
5585
5586 if Nkind (E) = N_Defining_Operator_Symbol
5587 and then not Error_Posted (Parent (E))
5588 then
5589 Check_Overriding_Indicator (E, Empty, Is_Primitive (E));
5590 end if;
5591 end Freeze_Subprogram;
5592
5593 ----------------------
5594 -- Is_Fully_Defined --
5595 ----------------------
5596
5597 function Is_Fully_Defined (T : Entity_Id) return Boolean is
5598 begin
5599 if Ekind (T) = E_Class_Wide_Type then
5600 return Is_Fully_Defined (Etype (T));
5601
5602 elsif Is_Array_Type (T) then
5603 return Is_Fully_Defined (Component_Type (T));
5604
5605 elsif Is_Record_Type (T)
5606 and not Is_Private_Type (T)
5607 then
5608 -- Verify that the record type has no components with private types
5609 -- without completion.
5610
5611 declare
5612 Comp : Entity_Id;
5613
5614 begin
5615 Comp := First_Component (T);
5616 while Present (Comp) loop
5617 if not Is_Fully_Defined (Etype (Comp)) then
5618 return False;
5619 end if;
5620
5621 Next_Component (Comp);
5622 end loop;
5623 return True;
5624 end;
5625
5626 -- For the designated type of an access to subprogram, all types in
5627 -- the profile must be fully defined.
5628
5629 elsif Ekind (T) = E_Subprogram_Type then
5630 declare
5631 F : Entity_Id;
5632
5633 begin
5634 F := First_Formal (T);
5635 while Present (F) loop
5636 if not Is_Fully_Defined (Etype (F)) then
5637 return False;
5638 end if;
5639
5640 Next_Formal (F);
5641 end loop;
5642
5643 return Is_Fully_Defined (Etype (T));
5644 end;
5645
5646 else
5647 return not Is_Private_Type (T)
5648 or else Present (Full_View (Base_Type (T)));
5649 end if;
5650 end Is_Fully_Defined;
5651
5652 ---------------------------------
5653 -- Process_Default_Expressions --
5654 ---------------------------------
5655
5656 procedure Process_Default_Expressions
5657 (E : Entity_Id;
5658 After : in out Node_Id)
5659 is
5660 Loc : constant Source_Ptr := Sloc (E);
5661 Dbody : Node_Id;
5662 Formal : Node_Id;
5663 Dcopy : Node_Id;
5664 Dnam : Entity_Id;
5665
5666 begin
5667 Set_Default_Expressions_Processed (E);
5668
5669 -- A subprogram instance and its associated anonymous subprogram share
5670 -- their signature. The default expression functions are defined in the
5671 -- wrapper packages for the anonymous subprogram, and should not be
5672 -- generated again for the instance.
5673
5674 if Is_Generic_Instance (E)
5675 and then Present (Alias (E))
5676 and then Default_Expressions_Processed (Alias (E))
5677 then
5678 return;
5679 end if;
5680
5681 Formal := First_Formal (E);
5682 while Present (Formal) loop
5683 if Present (Default_Value (Formal)) then
5684
5685 -- We work with a copy of the default expression because we
5686 -- do not want to disturb the original, since this would mess
5687 -- up the conformance checking.
5688
5689 Dcopy := New_Copy_Tree (Default_Value (Formal));
5690
5691 -- The analysis of the expression may generate insert actions,
5692 -- which of course must not be executed. We wrap those actions
5693 -- in a procedure that is not called, and later on eliminated.
5694 -- The following cases have no side-effects, and are analyzed
5695 -- directly.
5696
5697 if Nkind (Dcopy) = N_Identifier
5698 or else Nkind (Dcopy) = N_Expanded_Name
5699 or else Nkind (Dcopy) = N_Integer_Literal
5700 or else (Nkind (Dcopy) = N_Real_Literal
5701 and then not Vax_Float (Etype (Dcopy)))
5702 or else Nkind (Dcopy) = N_Character_Literal
5703 or else Nkind (Dcopy) = N_String_Literal
5704 or else Known_Null (Dcopy)
5705 or else (Nkind (Dcopy) = N_Attribute_Reference
5706 and then
5707 Attribute_Name (Dcopy) = Name_Null_Parameter)
5708 then
5709
5710 -- If there is no default function, we must still do a full
5711 -- analyze call on the default value, to ensure that all error
5712 -- checks are performed, e.g. those associated with static
5713 -- evaluation. Note: this branch will always be taken if the
5714 -- analyzer is turned off (but we still need the error checks).
5715
5716 -- Note: the setting of parent here is to meet the requirement
5717 -- that we can only analyze the expression while attached to
5718 -- the tree. Really the requirement is that the parent chain
5719 -- be set, we don't actually need to be in the tree.
5720
5721 Set_Parent (Dcopy, Declaration_Node (Formal));
5722 Analyze (Dcopy);
5723
5724 -- Default expressions are resolved with their own type if the
5725 -- context is generic, to avoid anomalies with private types.
5726
5727 if Ekind (Scope (E)) = E_Generic_Package then
5728 Resolve (Dcopy);
5729 else
5730 Resolve (Dcopy, Etype (Formal));
5731 end if;
5732
5733 -- If that resolved expression will raise constraint error,
5734 -- then flag the default value as raising constraint error.
5735 -- This allows a proper error message on the calls.
5736
5737 if Raises_Constraint_Error (Dcopy) then
5738 Set_Raises_Constraint_Error (Default_Value (Formal));
5739 end if;
5740
5741 -- If the default is a parameterless call, we use the name of
5742 -- the called function directly, and there is no body to build.
5743
5744 elsif Nkind (Dcopy) = N_Function_Call
5745 and then No (Parameter_Associations (Dcopy))
5746 then
5747 null;
5748
5749 -- Else construct and analyze the body of a wrapper procedure
5750 -- that contains an object declaration to hold the expression.
5751 -- Given that this is done only to complete the analysis, it
5752 -- simpler to build a procedure than a function which might
5753 -- involve secondary stack expansion.
5754
5755 else
5756 Dnam := Make_Temporary (Loc, 'D');
5757
5758 Dbody :=
5759 Make_Subprogram_Body (Loc,
5760 Specification =>
5761 Make_Procedure_Specification (Loc,
5762 Defining_Unit_Name => Dnam),
5763
5764 Declarations => New_List (
5765 Make_Object_Declaration (Loc,
5766 Defining_Identifier => Make_Temporary (Loc, 'T'),
5767 Object_Definition =>
5768 New_Occurrence_Of (Etype (Formal), Loc),
5769 Expression => New_Copy_Tree (Dcopy))),
5770
5771 Handled_Statement_Sequence =>
5772 Make_Handled_Sequence_Of_Statements (Loc,
5773 Statements => Empty_List));
5774
5775 Set_Scope (Dnam, Scope (E));
5776 Set_Assignment_OK (First (Declarations (Dbody)));
5777 Set_Is_Eliminated (Dnam);
5778 Insert_After (After, Dbody);
5779 Analyze (Dbody);
5780 After := Dbody;
5781 end if;
5782 end if;
5783
5784 Next_Formal (Formal);
5785 end loop;
5786 end Process_Default_Expressions;
5787
5788 ----------------------------------------
5789 -- Set_Component_Alignment_If_Not_Set --
5790 ----------------------------------------
5791
5792 procedure Set_Component_Alignment_If_Not_Set (Typ : Entity_Id) is
5793 begin
5794 -- Ignore if not base type, subtypes don't need anything
5795
5796 if Typ /= Base_Type (Typ) then
5797 return;
5798 end if;
5799
5800 -- Do not override existing representation
5801
5802 if Is_Packed (Typ) then
5803 return;
5804
5805 elsif Has_Specified_Layout (Typ) then
5806 return;
5807
5808 elsif Component_Alignment (Typ) /= Calign_Default then
5809 return;
5810
5811 else
5812 Set_Component_Alignment
5813 (Typ, Scope_Stack.Table
5814 (Scope_Stack.Last).Component_Alignment_Default);
5815 end if;
5816 end Set_Component_Alignment_If_Not_Set;
5817
5818 ------------------
5819 -- Undelay_Type --
5820 ------------------
5821
5822 procedure Undelay_Type (T : Entity_Id) is
5823 begin
5824 Set_Has_Delayed_Freeze (T, False);
5825 Set_Freeze_Node (T, Empty);
5826
5827 -- Since we don't want T to have a Freeze_Node, we don't want its
5828 -- Full_View or Corresponding_Record_Type to have one either.
5829
5830 -- ??? Fundamentally, this whole handling is a kludge. What we really
5831 -- want is to be sure that for an Itype that's part of record R and is a
5832 -- subtype of type T, that it's frozen after the later of the freeze
5833 -- points of R and T. We have no way of doing that directly, so what we
5834 -- do is force most such Itypes to be frozen as part of freezing R via
5835 -- this procedure and only delay the ones that need to be delayed
5836 -- (mostly the designated types of access types that are defined as part
5837 -- of the record).
5838
5839 if Is_Private_Type (T)
5840 and then Present (Full_View (T))
5841 and then Is_Itype (Full_View (T))
5842 and then Is_Record_Type (Scope (Full_View (T)))
5843 then
5844 Undelay_Type (Full_View (T));
5845 end if;
5846
5847 if Is_Concurrent_Type (T)
5848 and then Present (Corresponding_Record_Type (T))
5849 and then Is_Itype (Corresponding_Record_Type (T))
5850 and then Is_Record_Type (Scope (Corresponding_Record_Type (T)))
5851 then
5852 Undelay_Type (Corresponding_Record_Type (T));
5853 end if;
5854 end Undelay_Type;
5855
5856 ------------------
5857 -- Warn_Overlay --
5858 ------------------
5859
5860 procedure Warn_Overlay
5861 (Expr : Node_Id;
5862 Typ : Entity_Id;
5863 Nam : Entity_Id)
5864 is
5865 Ent : constant Entity_Id := Entity (Nam);
5866 -- The object to which the address clause applies
5867
5868 Init : Node_Id;
5869 Old : Entity_Id := Empty;
5870 Decl : Node_Id;
5871
5872 begin
5873 -- No warning if address clause overlay warnings are off
5874
5875 if not Address_Clause_Overlay_Warnings then
5876 return;
5877 end if;
5878
5879 -- No warning if there is an explicit initialization
5880
5881 Init := Original_Node (Expression (Declaration_Node (Ent)));
5882
5883 if Present (Init) and then Comes_From_Source (Init) then
5884 return;
5885 end if;
5886
5887 -- We only give the warning for non-imported entities of a type for
5888 -- which a non-null base init proc is defined, or for objects of access
5889 -- types with implicit null initialization, or when Normalize_Scalars
5890 -- applies and the type is scalar or a string type (the latter being
5891 -- tested for because predefined String types are initialized by inline
5892 -- code rather than by an init_proc). Note that we do not give the
5893 -- warning for Initialize_Scalars, since we suppressed initialization
5894 -- in this case. Also, do not warn if Suppress_Initialization is set.
5895
5896 if Present (Expr)
5897 and then not Is_Imported (Ent)
5898 and then not Initialization_Suppressed (Typ)
5899 and then (Has_Non_Null_Base_Init_Proc (Typ)
5900 or else Is_Access_Type (Typ)
5901 or else (Normalize_Scalars
5902 and then (Is_Scalar_Type (Typ)
5903 or else Is_String_Type (Typ))))
5904 then
5905 if Nkind (Expr) = N_Attribute_Reference
5906 and then Is_Entity_Name (Prefix (Expr))
5907 then
5908 Old := Entity (Prefix (Expr));
5909
5910 elsif Is_Entity_Name (Expr)
5911 and then Ekind (Entity (Expr)) = E_Constant
5912 then
5913 Decl := Declaration_Node (Entity (Expr));
5914
5915 if Nkind (Decl) = N_Object_Declaration
5916 and then Present (Expression (Decl))
5917 and then Nkind (Expression (Decl)) = N_Attribute_Reference
5918 and then Is_Entity_Name (Prefix (Expression (Decl)))
5919 then
5920 Old := Entity (Prefix (Expression (Decl)));
5921
5922 elsif Nkind (Expr) = N_Function_Call then
5923 return;
5924 end if;
5925
5926 -- A function call (most likely to To_Address) is probably not an
5927 -- overlay, so skip warning. Ditto if the function call was inlined
5928 -- and transformed into an entity.
5929
5930 elsif Nkind (Original_Node (Expr)) = N_Function_Call then
5931 return;
5932 end if;
5933
5934 Decl := Next (Parent (Expr));
5935
5936 -- If a pragma Import follows, we assume that it is for the current
5937 -- target of the address clause, and skip the warning.
5938
5939 if Present (Decl)
5940 and then Nkind (Decl) = N_Pragma
5941 and then Pragma_Name (Decl) = Name_Import
5942 then
5943 return;
5944 end if;
5945
5946 if Present (Old) then
5947 Error_Msg_Node_2 := Old;
5948 Error_Msg_N
5949 ("default initialization of & may modify &?",
5950 Nam);
5951 else
5952 Error_Msg_N
5953 ("default initialization of & may modify overlaid storage?",
5954 Nam);
5955 end if;
5956
5957 -- Add friendly warning if initialization comes from a packed array
5958 -- component.
5959
5960 if Is_Record_Type (Typ) then
5961 declare
5962 Comp : Entity_Id;
5963
5964 begin
5965 Comp := First_Component (Typ);
5966 while Present (Comp) loop
5967 if Nkind (Parent (Comp)) = N_Component_Declaration
5968 and then Present (Expression (Parent (Comp)))
5969 then
5970 exit;
5971 elsif Is_Array_Type (Etype (Comp))
5972 and then Present (Packed_Array_Type (Etype (Comp)))
5973 then
5974 Error_Msg_NE
5975 ("\packed array component& " &
5976 "will be initialized to zero?",
5977 Nam, Comp);
5978 exit;
5979 else
5980 Next_Component (Comp);
5981 end if;
5982 end loop;
5983 end;
5984 end if;
5985
5986 Error_Msg_N
5987 ("\use pragma Import for & to " &
5988 "suppress initialization (RM B.1(24))?",
5989 Nam);
5990 end if;
5991 end Warn_Overlay;
5992
5993 end Freeze;