File : sem_ch13.adb
1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- S E M _ C H 1 3 --
6 -- --
7 -- B o d y --
8 -- --
9 -- Copyright (C) 1992-2016, 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 Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Debug; use Debug;
30 with Einfo; use Einfo;
31 with Elists; use Elists;
32 with Errout; use Errout;
33 with Exp_Disp; use Exp_Disp;
34 with Exp_Tss; use Exp_Tss;
35 with Exp_Util; use Exp_Util;
36 with Freeze; use Freeze;
37 with Ghost; use Ghost;
38 with Lib; use Lib;
39 with Lib.Xref; use Lib.Xref;
40 with Namet; use Namet;
41 with Nlists; use Nlists;
42 with Nmake; use Nmake;
43 with Opt; use Opt;
44 with Restrict; use Restrict;
45 with Rident; use Rident;
46 with Rtsfind; use Rtsfind;
47 with Sem; use Sem;
48 with Sem_Aux; use Sem_Aux;
49 with Sem_Case; use Sem_Case;
50 with Sem_Ch3; use Sem_Ch3;
51 with Sem_Ch6; use Sem_Ch6;
52 with Sem_Ch8; use Sem_Ch8;
53 with Sem_Dim; use Sem_Dim;
54 with Sem_Disp; use Sem_Disp;
55 with Sem_Eval; use Sem_Eval;
56 with Sem_Prag; use Sem_Prag;
57 with Sem_Res; use Sem_Res;
58 with Sem_Type; use Sem_Type;
59 with Sem_Util; use Sem_Util;
60 with Sem_Warn; use Sem_Warn;
61 with Sinput; use Sinput;
62 with Snames; use Snames;
63 with Stand; use Stand;
64 with Sinfo; use Sinfo;
65 with Targparm; use Targparm;
66 with Ttypes; use Ttypes;
67 with Tbuild; use Tbuild;
68 with Urealp; use Urealp;
69 with Warnsw; use Warnsw;
70
71 with GNAT.Heap_Sort_G;
72
73 package body Sem_Ch13 is
74
75 SSU : constant Pos := System_Storage_Unit;
76 -- Convenient short hand for commonly used constant
77
78 -----------------------
79 -- Local Subprograms --
80 -----------------------
81
82 procedure Alignment_Check_For_Size_Change (Typ : Entity_Id; Size : Uint);
83 -- This routine is called after setting one of the sizes of type entity
84 -- Typ to Size. The purpose is to deal with the situation of a derived
85 -- type whose inherited alignment is no longer appropriate for the new
86 -- size value. In this case, we reset the Alignment to unknown.
87
88 procedure Build_Discrete_Static_Predicate
89 (Typ : Entity_Id;
90 Expr : Node_Id;
91 Nam : Name_Id);
92 -- Given a predicated type Typ, where Typ is a discrete static subtype,
93 -- whose predicate expression is Expr, tests if Expr is a static predicate,
94 -- and if so, builds the predicate range list. Nam is the name of the one
95 -- argument to the predicate function. Occurrences of the type name in the
96 -- predicate expression have been replaced by identifier references to this
97 -- name, which is unique, so any identifier with Chars matching Nam must be
98 -- a reference to the type. If the predicate is non-static, this procedure
99 -- returns doing nothing. If the predicate is static, then the predicate
100 -- list is stored in Static_Discrete_Predicate (Typ), and the Expr is
101 -- rewritten as a canonicalized membership operation.
102
103 function Build_Export_Import_Pragma
104 (Asp : Node_Id;
105 Id : Entity_Id) return Node_Id;
106 -- Create the corresponding pragma for aspect Export or Import denoted by
107 -- Asp. Id is the related entity subject to the aspect. Return Empty when
108 -- the expression of aspect Asp evaluates to False or is erroneous.
109
110 function Build_Predicate_Function_Declaration
111 (Typ : Entity_Id) return Node_Id;
112 -- Build the declaration for a predicate function. The declaration is built
113 -- at the end of the declarative part containing the type definition, which
114 -- may be before the freeze point of the type. The predicate expression is
115 -- pre-analyzed at this point, to catch visibility errors.
116
117 procedure Build_Predicate_Functions (Typ : Entity_Id; N : Node_Id);
118 -- If Typ has predicates (indicated by Has_Predicates being set for Typ),
119 -- then either there are pragma Predicate entries on the rep chain for the
120 -- type (note that Predicate aspects are converted to pragma Predicate), or
121 -- there are inherited aspects from a parent type, or ancestor subtypes.
122 -- This procedure builds body for the Predicate function that tests these
123 -- predicates. N is the freeze node for the type. The spec of the function
124 -- is inserted before the freeze node, and the body of the function is
125 -- inserted after the freeze node. If the predicate expression has a least
126 -- one Raise_Expression, then this procedure also builds the M version of
127 -- the predicate function for use in membership tests.
128
129 procedure Check_Pool_Size_Clash (Ent : Entity_Id; SP, SS : Node_Id);
130 -- Called if both Storage_Pool and Storage_Size attribute definition
131 -- clauses (SP and SS) are present for entity Ent. Issue error message.
132
133 procedure Freeze_Entity_Checks (N : Node_Id);
134 -- Called from Analyze_Freeze_Entity and Analyze_Generic_Freeze Entity
135 -- to generate appropriate semantic checks that are delayed until this
136 -- point (they had to be delayed this long for cases of delayed aspects,
137 -- e.g. analysis of statically predicated subtypes in choices, for which
138 -- we have to be sure the subtypes in question are frozen before checking).
139
140 function Get_Alignment_Value (Expr : Node_Id) return Uint;
141 -- Given the expression for an alignment value, returns the corresponding
142 -- Uint value. If the value is inappropriate, then error messages are
143 -- posted as required, and a value of No_Uint is returned.
144
145 procedure Get_Interfacing_Aspects
146 (Iface_Asp : Node_Id;
147 Conv_Asp : out Node_Id;
148 EN_Asp : out Node_Id;
149 Expo_Asp : out Node_Id;
150 Imp_Asp : out Node_Id;
151 LN_Asp : out Node_Id;
152 Do_Checks : Boolean := False);
153 -- Given a single interfacing aspect Iface_Asp, retrieve other interfacing
154 -- aspects that apply to the same related entity. The aspects considered by
155 -- this routine are as follows:
156 --
157 -- Conv_Asp - aspect Convention
158 -- EN_Asp - aspect External_Name
159 -- Expo_Asp - aspect Export
160 -- Imp_Asp - aspect Import
161 -- LN_Asp - aspect Link_Name
162 --
163 -- When flag Do_Checks is set, this routine will flag duplicate uses of
164 -- aspects.
165
166 function Is_Operational_Item (N : Node_Id) return Boolean;
167 -- A specification for a stream attribute is allowed before the full type
168 -- is declared, as explained in AI-00137 and the corrigendum. Attributes
169 -- that do not specify a representation characteristic are operational
170 -- attributes.
171
172 function Is_Predicate_Static
173 (Expr : Node_Id;
174 Nam : Name_Id) return Boolean;
175 -- Given predicate expression Expr, tests if Expr is predicate-static in
176 -- the sense of the rules in (RM 3.2.4 (15-24)). Occurrences of the type
177 -- name in the predicate expression have been replaced by references to
178 -- an identifier whose Chars field is Nam. This name is unique, so any
179 -- identifier with Chars matching Nam must be a reference to the type.
180 -- Returns True if the expression is predicate-static and False otherwise,
181 -- but is not in the business of setting flags or issuing error messages.
182 --
183 -- Only scalar types can have static predicates, so False is always
184 -- returned for non-scalar types.
185 --
186 -- Note: the RM seems to suggest that string types can also have static
187 -- predicates. But that really makes lttle sense as very few useful
188 -- predicates can be constructed for strings. Remember that:
189 --
190 -- "ABC" < "DEF"
191 --
192 -- is not a static expression. So even though the clearly faulty RM wording
193 -- allows the following:
194 --
195 -- subtype S is String with Static_Predicate => S < "DEF"
196 --
197 -- We can't allow this, otherwise we have predicate-static applying to a
198 -- larger class than static expressions, which was never intended.
199
200 procedure New_Stream_Subprogram
201 (N : Node_Id;
202 Ent : Entity_Id;
203 Subp : Entity_Id;
204 Nam : TSS_Name_Type);
205 -- Create a subprogram renaming of a given stream attribute to the
206 -- designated subprogram and then in the tagged case, provide this as a
207 -- primitive operation, or in the untagged case make an appropriate TSS
208 -- entry. This is more properly an expansion activity than just semantics,
209 -- but the presence of user-defined stream functions for limited types
210 -- is a legality check, which is why this takes place here rather than in
211 -- exp_ch13, where it was previously. Nam indicates the name of the TSS
212 -- function to be generated.
213 --
214 -- To avoid elaboration anomalies with freeze nodes, for untagged types
215 -- we generate both a subprogram declaration and a subprogram renaming
216 -- declaration, so that the attribute specification is handled as a
217 -- renaming_as_body. For tagged types, the specification is one of the
218 -- primitive specs.
219
220 procedure Resolve_Iterable_Operation
221 (N : Node_Id;
222 Cursor : Entity_Id;
223 Typ : Entity_Id;
224 Nam : Name_Id);
225 -- If the name of a primitive operation for an Iterable aspect is
226 -- overloaded, resolve according to required signature.
227
228 procedure Set_Biased
229 (E : Entity_Id;
230 N : Node_Id;
231 Msg : String;
232 Biased : Boolean := True);
233 -- If Biased is True, sets Has_Biased_Representation flag for E, and
234 -- outputs a warning message at node N if Warn_On_Biased_Representation is
235 -- is True. This warning inserts the string Msg to describe the construct
236 -- causing biasing.
237
238 ----------------------------------------------
239 -- Table for Validate_Unchecked_Conversions --
240 ----------------------------------------------
241
242 -- The following table collects unchecked conversions for validation.
243 -- Entries are made by Validate_Unchecked_Conversion and then the call
244 -- to Validate_Unchecked_Conversions does the actual error checking and
245 -- posting of warnings. The reason for this delayed processing is to take
246 -- advantage of back-annotations of size and alignment values performed by
247 -- the back end.
248
249 -- Note: the reason we store a Source_Ptr value instead of a Node_Id is
250 -- that by the time Validate_Unchecked_Conversions is called, Sprint will
251 -- already have modified all Sloc values if the -gnatD option is set.
252
253 type UC_Entry is record
254 Eloc : Source_Ptr; -- node used for posting warnings
255 Source : Entity_Id; -- source type for unchecked conversion
256 Target : Entity_Id; -- target type for unchecked conversion
257 Act_Unit : Entity_Id; -- actual function instantiated
258 end record;
259
260 package Unchecked_Conversions is new Table.Table (
261 Table_Component_Type => UC_Entry,
262 Table_Index_Type => Int,
263 Table_Low_Bound => 1,
264 Table_Initial => 50,
265 Table_Increment => 200,
266 Table_Name => "Unchecked_Conversions");
267
268 ----------------------------------------
269 -- Table for Validate_Address_Clauses --
270 ----------------------------------------
271
272 -- If an address clause has the form
273
274 -- for X'Address use Expr
275
276 -- where Expr has a value known at compile time or is of the form Y'Address
277 -- or recursively is a reference to a constant initialized with either of
278 -- these forms, and the value of Expr is not a multiple of X's alignment,
279 -- or if Y has a smaller alignment than X, then that merits a warning about
280 -- possible bad alignment. The following table collects address clauses of
281 -- this kind. We put these in a table so that they can be checked after the
282 -- back end has completed annotation of the alignments of objects, since we
283 -- can catch more cases that way.
284
285 type Address_Clause_Check_Record is record
286 N : Node_Id;
287 -- The address clause
288
289 X : Entity_Id;
290 -- The entity of the object subject to the address clause
291
292 A : Uint;
293 -- The value of the address in the first case
294
295 Y : Entity_Id;
296 -- The entity of the object being overlaid in the second case
297
298 Off : Boolean;
299 -- Whether the address is offset within Y in the second case
300 end record;
301
302 package Address_Clause_Checks is new Table.Table (
303 Table_Component_Type => Address_Clause_Check_Record,
304 Table_Index_Type => Int,
305 Table_Low_Bound => 1,
306 Table_Initial => 20,
307 Table_Increment => 200,
308 Table_Name => "Address_Clause_Checks");
309
310 -----------------------------------------
311 -- Adjust_Record_For_Reverse_Bit_Order --
312 -----------------------------------------
313
314 procedure Adjust_Record_For_Reverse_Bit_Order (R : Entity_Id) is
315 Comp : Node_Id;
316 CC : Node_Id;
317
318 begin
319 -- Processing depends on version of Ada
320
321 -- For Ada 95, we just renumber bits within a storage unit. We do the
322 -- same for Ada 83 mode, since we recognize the Bit_Order attribute in
323 -- Ada 83, and are free to add this extension.
324
325 if Ada_Version < Ada_2005 then
326 Comp := First_Component_Or_Discriminant (R);
327 while Present (Comp) loop
328 CC := Component_Clause (Comp);
329
330 -- If component clause is present, then deal with the non-default
331 -- bit order case for Ada 95 mode.
332
333 -- We only do this processing for the base type, and in fact that
334 -- is important, since otherwise if there are record subtypes, we
335 -- could reverse the bits once for each subtype, which is wrong.
336
337 if Present (CC) and then Ekind (R) = E_Record_Type then
338 declare
339 CFB : constant Uint := Component_Bit_Offset (Comp);
340 CSZ : constant Uint := Esize (Comp);
341 CLC : constant Node_Id := Component_Clause (Comp);
342 Pos : constant Node_Id := Position (CLC);
343 FB : constant Node_Id := First_Bit (CLC);
344
345 Storage_Unit_Offset : constant Uint :=
346 CFB / System_Storage_Unit;
347
348 Start_Bit : constant Uint :=
349 CFB mod System_Storage_Unit;
350
351 begin
352 -- Cases where field goes over storage unit boundary
353
354 if Start_Bit + CSZ > System_Storage_Unit then
355
356 -- Allow multi-byte field but generate warning
357
358 if Start_Bit mod System_Storage_Unit = 0
359 and then CSZ mod System_Storage_Unit = 0
360 then
361 Error_Msg_N
362 ("info: multi-byte field specified with "
363 & "non-standard Bit_Order?V?", CLC);
364
365 if Bytes_Big_Endian then
366 Error_Msg_N
367 ("\bytes are not reversed "
368 & "(component is big-endian)?V?", CLC);
369 else
370 Error_Msg_N
371 ("\bytes are not reversed "
372 & "(component is little-endian)?V?", CLC);
373 end if;
374
375 -- Do not allow non-contiguous field
376
377 else
378 Error_Msg_N
379 ("attempt to specify non-contiguous field "
380 & "not permitted", CLC);
381 Error_Msg_N
382 ("\caused by non-standard Bit_Order "
383 & "specified", CLC);
384 Error_Msg_N
385 ("\consider possibility of using "
386 & "Ada 2005 mode here", CLC);
387 end if;
388
389 -- Case where field fits in one storage unit
390
391 else
392 -- Give warning if suspicious component clause
393
394 if Intval (FB) >= System_Storage_Unit
395 and then Warn_On_Reverse_Bit_Order
396 then
397 Error_Msg_N
398 ("info: Bit_Order clause does not affect " &
399 "byte ordering?V?", Pos);
400 Error_Msg_Uint_1 :=
401 Intval (Pos) + Intval (FB) /
402 System_Storage_Unit;
403 Error_Msg_N
404 ("info: position normalized to ^ before bit " &
405 "order interpreted?V?", Pos);
406 end if;
407
408 -- Here is where we fix up the Component_Bit_Offset value
409 -- to account for the reverse bit order. Some examples of
410 -- what needs to be done are:
411
412 -- First_Bit .. Last_Bit Component_Bit_Offset
413 -- old new old new
414
415 -- 0 .. 0 7 .. 7 0 7
416 -- 0 .. 1 6 .. 7 0 6
417 -- 0 .. 2 5 .. 7 0 5
418 -- 0 .. 7 0 .. 7 0 4
419
420 -- 1 .. 1 6 .. 6 1 6
421 -- 1 .. 4 3 .. 6 1 3
422 -- 4 .. 7 0 .. 3 4 0
423
424 -- The rule is that the first bit is is obtained by
425 -- subtracting the old ending bit from storage_unit - 1.
426
427 Set_Component_Bit_Offset
428 (Comp,
429 (Storage_Unit_Offset * System_Storage_Unit) +
430 (System_Storage_Unit - 1) -
431 (Start_Bit + CSZ - 1));
432
433 Set_Normalized_First_Bit
434 (Comp,
435 Component_Bit_Offset (Comp) mod
436 System_Storage_Unit);
437 end if;
438 end;
439 end if;
440
441 Next_Component_Or_Discriminant (Comp);
442 end loop;
443
444 -- For Ada 2005, we do machine scalar processing, as fully described In
445 -- AI-133. This involves gathering all components which start at the
446 -- same byte offset and processing them together. Same approach is still
447 -- valid in later versions including Ada 2012.
448
449 else
450 declare
451 Max_Machine_Scalar_Size : constant Uint :=
452 UI_From_Int
453 (Standard_Long_Long_Integer_Size);
454 -- We use this as the maximum machine scalar size
455
456 Num_CC : Natural;
457 SSU : constant Uint := UI_From_Int (System_Storage_Unit);
458
459 begin
460 -- This first loop through components does two things. First it
461 -- deals with the case of components with component clauses whose
462 -- length is greater than the maximum machine scalar size (either
463 -- accepting them or rejecting as needed). Second, it counts the
464 -- number of components with component clauses whose length does
465 -- not exceed this maximum for later processing.
466
467 Num_CC := 0;
468 Comp := First_Component_Or_Discriminant (R);
469 while Present (Comp) loop
470 CC := Component_Clause (Comp);
471
472 if Present (CC) then
473 declare
474 Fbit : constant Uint := Static_Integer (First_Bit (CC));
475 Lbit : constant Uint := Static_Integer (Last_Bit (CC));
476
477 begin
478 -- Case of component with last bit >= max machine scalar
479
480 if Lbit >= Max_Machine_Scalar_Size then
481
482 -- This is allowed only if first bit is zero, and
483 -- last bit + 1 is a multiple of storage unit size.
484
485 if Fbit = 0 and then (Lbit + 1) mod SSU = 0 then
486
487 -- This is the case to give a warning if enabled
488
489 if Warn_On_Reverse_Bit_Order then
490 Error_Msg_N
491 ("info: multi-byte field specified with "
492 & "non-standard Bit_Order?V?", CC);
493
494 if Bytes_Big_Endian then
495 Error_Msg_N
496 ("\bytes are not reversed "
497 & "(component is big-endian)?V?", CC);
498 else
499 Error_Msg_N
500 ("\bytes are not reversed "
501 & "(component is little-endian)?V?", CC);
502 end if;
503 end if;
504
505 -- Give error message for RM 13.5.1(10) violation
506
507 else
508 Error_Msg_FE
509 ("machine scalar rules not followed for&",
510 First_Bit (CC), Comp);
511
512 Error_Msg_Uint_1 := Lbit + 1;
513 Error_Msg_Uint_2 := Max_Machine_Scalar_Size;
514 Error_Msg_F
515 ("\last bit + 1 (^) exceeds maximum machine "
516 & "scalar size (^)",
517 First_Bit (CC));
518
519 if (Lbit + 1) mod SSU /= 0 then
520 Error_Msg_Uint_1 := SSU;
521 Error_Msg_F
522 ("\and is not a multiple of Storage_Unit (^) "
523 & "(RM 13.5.1(10))",
524 First_Bit (CC));
525
526 else
527 Error_Msg_Uint_1 := Fbit;
528 Error_Msg_F
529 ("\and first bit (^) is non-zero "
530 & "(RM 13.4.1(10))",
531 First_Bit (CC));
532 end if;
533 end if;
534
535 -- OK case of machine scalar related component clause,
536 -- For now, just count them.
537
538 else
539 Num_CC := Num_CC + 1;
540 end if;
541 end;
542 end if;
543
544 Next_Component_Or_Discriminant (Comp);
545 end loop;
546
547 -- We need to sort the component clauses on the basis of the
548 -- Position values in the clause, so we can group clauses with
549 -- the same Position together to determine the relevant machine
550 -- scalar size.
551
552 Sort_CC : declare
553 Comps : array (0 .. Num_CC) of Entity_Id;
554 -- Array to collect component and discriminant entities. The
555 -- data starts at index 1, the 0'th entry is for the sort
556 -- routine.
557
558 function CP_Lt (Op1, Op2 : Natural) return Boolean;
559 -- Compare routine for Sort
560
561 procedure CP_Move (From : Natural; To : Natural);
562 -- Move routine for Sort
563
564 package Sorting is new GNAT.Heap_Sort_G (CP_Move, CP_Lt);
565
566 Start : Natural;
567 Stop : Natural;
568 -- Start and stop positions in the component list of the set of
569 -- components with the same starting position (that constitute
570 -- components in a single machine scalar).
571
572 MaxL : Uint;
573 -- Maximum last bit value of any component in this set
574
575 MSS : Uint;
576 -- Corresponding machine scalar size
577
578 -----------
579 -- CP_Lt --
580 -----------
581
582 function CP_Lt (Op1, Op2 : Natural) return Boolean is
583 begin
584 return Position (Component_Clause (Comps (Op1))) <
585 Position (Component_Clause (Comps (Op2)));
586 end CP_Lt;
587
588 -------------
589 -- CP_Move --
590 -------------
591
592 procedure CP_Move (From : Natural; To : Natural) is
593 begin
594 Comps (To) := Comps (From);
595 end CP_Move;
596
597 -- Start of processing for Sort_CC
598
599 begin
600 -- Collect the machine scalar relevant component clauses
601
602 Num_CC := 0;
603 Comp := First_Component_Or_Discriminant (R);
604 while Present (Comp) loop
605 declare
606 CC : constant Node_Id := Component_Clause (Comp);
607
608 begin
609 -- Collect only component clauses whose last bit is less
610 -- than machine scalar size. Any component clause whose
611 -- last bit exceeds this value does not take part in
612 -- machine scalar layout considerations. The test for
613 -- Error_Posted makes sure we exclude component clauses
614 -- for which we already posted an error.
615
616 if Present (CC)
617 and then not Error_Posted (Last_Bit (CC))
618 and then Static_Integer (Last_Bit (CC)) <
619 Max_Machine_Scalar_Size
620 then
621 Num_CC := Num_CC + 1;
622 Comps (Num_CC) := Comp;
623 end if;
624 end;
625
626 Next_Component_Or_Discriminant (Comp);
627 end loop;
628
629 -- Sort by ascending position number
630
631 Sorting.Sort (Num_CC);
632
633 -- We now have all the components whose size does not exceed
634 -- the max machine scalar value, sorted by starting position.
635 -- In this loop we gather groups of clauses starting at the
636 -- same position, to process them in accordance with AI-133.
637
638 Stop := 0;
639 while Stop < Num_CC loop
640 Start := Stop + 1;
641 Stop := Start;
642 MaxL :=
643 Static_Integer
644 (Last_Bit (Component_Clause (Comps (Start))));
645 while Stop < Num_CC loop
646 if Static_Integer
647 (Position (Component_Clause (Comps (Stop + 1)))) =
648 Static_Integer
649 (Position (Component_Clause (Comps (Stop))))
650 then
651 Stop := Stop + 1;
652 MaxL :=
653 UI_Max
654 (MaxL,
655 Static_Integer
656 (Last_Bit
657 (Component_Clause (Comps (Stop)))));
658 else
659 exit;
660 end if;
661 end loop;
662
663 -- Now we have a group of component clauses from Start to
664 -- Stop whose positions are identical, and MaxL is the
665 -- maximum last bit value of any of these components.
666
667 -- We need to determine the corresponding machine scalar
668 -- size. This loop assumes that machine scalar sizes are
669 -- even, and that each possible machine scalar has twice
670 -- as many bits as the next smaller one.
671
672 MSS := Max_Machine_Scalar_Size;
673 while MSS mod 2 = 0
674 and then (MSS / 2) >= SSU
675 and then (MSS / 2) > MaxL
676 loop
677 MSS := MSS / 2;
678 end loop;
679
680 -- Here is where we fix up the Component_Bit_Offset value
681 -- to account for the reverse bit order. Some examples of
682 -- what needs to be done for the case of a machine scalar
683 -- size of 8 are:
684
685 -- First_Bit .. Last_Bit Component_Bit_Offset
686 -- old new old new
687
688 -- 0 .. 0 7 .. 7 0 7
689 -- 0 .. 1 6 .. 7 0 6
690 -- 0 .. 2 5 .. 7 0 5
691 -- 0 .. 7 0 .. 7 0 4
692
693 -- 1 .. 1 6 .. 6 1 6
694 -- 1 .. 4 3 .. 6 1 3
695 -- 4 .. 7 0 .. 3 4 0
696
697 -- The rule is that the first bit is obtained by subtracting
698 -- the old ending bit from machine scalar size - 1.
699
700 for C in Start .. Stop loop
701 declare
702 Comp : constant Entity_Id := Comps (C);
703 CC : constant Node_Id := Component_Clause (Comp);
704
705 LB : constant Uint := Static_Integer (Last_Bit (CC));
706 NFB : constant Uint := MSS - Uint_1 - LB;
707 NLB : constant Uint := NFB + Esize (Comp) - 1;
708 Pos : constant Uint := Static_Integer (Position (CC));
709
710 begin
711 if Warn_On_Reverse_Bit_Order then
712 Error_Msg_Uint_1 := MSS;
713 Error_Msg_N
714 ("info: reverse bit order in machine " &
715 "scalar of length^?V?", First_Bit (CC));
716 Error_Msg_Uint_1 := NFB;
717 Error_Msg_Uint_2 := NLB;
718
719 if Bytes_Big_Endian then
720 Error_Msg_NE
721 ("\big-endian range for component "
722 & "& is ^ .. ^?V?", First_Bit (CC), Comp);
723 else
724 Error_Msg_NE
725 ("\little-endian range for component"
726 & "& is ^ .. ^?V?", First_Bit (CC), Comp);
727 end if;
728 end if;
729
730 Set_Component_Bit_Offset (Comp, Pos * SSU + NFB);
731 Set_Normalized_First_Bit (Comp, NFB mod SSU);
732 end;
733 end loop;
734 end loop;
735 end Sort_CC;
736 end;
737 end if;
738 end Adjust_Record_For_Reverse_Bit_Order;
739
740 -------------------------------------
741 -- Alignment_Check_For_Size_Change --
742 -------------------------------------
743
744 procedure Alignment_Check_For_Size_Change (Typ : Entity_Id; Size : Uint) is
745 begin
746 -- If the alignment is known, and not set by a rep clause, and is
747 -- inconsistent with the size being set, then reset it to unknown,
748 -- we assume in this case that the size overrides the inherited
749 -- alignment, and that the alignment must be recomputed.
750
751 if Known_Alignment (Typ)
752 and then not Has_Alignment_Clause (Typ)
753 and then Size mod (Alignment (Typ) * SSU) /= 0
754 then
755 Init_Alignment (Typ);
756 end if;
757 end Alignment_Check_For_Size_Change;
758
759 -------------------------------------
760 -- Analyze_Aspects_At_Freeze_Point --
761 -------------------------------------
762
763 procedure Analyze_Aspects_At_Freeze_Point (E : Entity_Id) is
764 procedure Analyze_Aspect_Default_Value (ASN : Node_Id);
765 -- This routine analyzes an Aspect_Default_[Component_]Value denoted by
766 -- the aspect specification node ASN.
767
768 procedure Inherit_Delayed_Rep_Aspects (ASN : Node_Id);
769 -- As discussed in the spec of Aspects (see Aspect_Delay declaration),
770 -- a derived type can inherit aspects from its parent which have been
771 -- specified at the time of the derivation using an aspect, as in:
772 --
773 -- type A is range 1 .. 10
774 -- with Size => Not_Defined_Yet;
775 -- ..
776 -- type B is new A;
777 -- ..
778 -- Not_Defined_Yet : constant := 64;
779 --
780 -- In this example, the Size of A is considered to be specified prior
781 -- to the derivation, and thus inherited, even though the value is not
782 -- known at the time of derivation. To deal with this, we use two entity
783 -- flags. The flag Has_Derived_Rep_Aspects is set in the parent type (A
784 -- here), and then the flag May_Inherit_Delayed_Rep_Aspects is set in
785 -- the derived type (B here). If this flag is set when the derived type
786 -- is frozen, then this procedure is called to ensure proper inheritance
787 -- of all delayed aspects from the parent type. The derived type is E,
788 -- the argument to Analyze_Aspects_At_Freeze_Point. ASN is the first
789 -- aspect specification node in the Rep_Item chain for the parent type.
790
791 procedure Make_Pragma_From_Boolean_Aspect (ASN : Node_Id);
792 -- Given an aspect specification node ASN whose expression is an
793 -- optional Boolean, this routines creates the corresponding pragma
794 -- at the freezing point.
795
796 ----------------------------------
797 -- Analyze_Aspect_Default_Value --
798 ----------------------------------
799
800 procedure Analyze_Aspect_Default_Value (ASN : Node_Id) is
801 A_Id : constant Aspect_Id := Get_Aspect_Id (ASN);
802 Ent : constant Entity_Id := Entity (ASN);
803 Expr : constant Node_Id := Expression (ASN);
804 Id : constant Node_Id := Identifier (ASN);
805
806 begin
807 Error_Msg_Name_1 := Chars (Id);
808
809 if not Is_Type (Ent) then
810 Error_Msg_N ("aspect% can only apply to a type", Id);
811 return;
812
813 elsif not Is_First_Subtype (Ent) then
814 Error_Msg_N ("aspect% cannot apply to subtype", Id);
815 return;
816
817 elsif A_Id = Aspect_Default_Value
818 and then not Is_Scalar_Type (Ent)
819 then
820 Error_Msg_N ("aspect% can only be applied to scalar type", Id);
821 return;
822
823 elsif A_Id = Aspect_Default_Component_Value then
824 if not Is_Array_Type (Ent) then
825 Error_Msg_N ("aspect% can only be applied to array type", Id);
826 return;
827
828 elsif not Is_Scalar_Type (Component_Type (Ent)) then
829 Error_Msg_N ("aspect% requires scalar components", Id);
830 return;
831 end if;
832 end if;
833
834 Set_Has_Default_Aspect (Base_Type (Ent));
835
836 if Is_Scalar_Type (Ent) then
837 Set_Default_Aspect_Value (Base_Type (Ent), Expr);
838 else
839 Set_Default_Aspect_Component_Value (Base_Type (Ent), Expr);
840 end if;
841 end Analyze_Aspect_Default_Value;
842
843 ---------------------------------
844 -- Inherit_Delayed_Rep_Aspects --
845 ---------------------------------
846
847 procedure Inherit_Delayed_Rep_Aspects (ASN : Node_Id) is
848 A_Id : constant Aspect_Id := Get_Aspect_Id (ASN);
849 P : constant Entity_Id := Entity (ASN);
850 -- Entithy for parent type
851
852 N : Node_Id;
853 -- Item from Rep_Item chain
854
855 A : Aspect_Id;
856
857 begin
858 -- Loop through delayed aspects for the parent type
859
860 N := ASN;
861 while Present (N) loop
862 if Nkind (N) = N_Aspect_Specification then
863 exit when Entity (N) /= P;
864
865 if Is_Delayed_Aspect (N) then
866 A := Get_Aspect_Id (Chars (Identifier (N)));
867
868 -- Process delayed rep aspect. For Boolean attributes it is
869 -- not possible to cancel an attribute once set (the attempt
870 -- to use an aspect with xxx => False is an error) for a
871 -- derived type. So for those cases, we do not have to check
872 -- if a clause has been given for the derived type, since it
873 -- is harmless to set it again if it is already set.
874
875 case A is
876
877 -- Alignment
878
879 when Aspect_Alignment =>
880 if not Has_Alignment_Clause (E) then
881 Set_Alignment (E, Alignment (P));
882 end if;
883
884 -- Atomic
885
886 when Aspect_Atomic =>
887 if Is_Atomic (P) then
888 Set_Is_Atomic (E);
889 end if;
890
891 -- Atomic_Components
892
893 when Aspect_Atomic_Components =>
894 if Has_Atomic_Components (P) then
895 Set_Has_Atomic_Components (Base_Type (E));
896 end if;
897
898 -- Bit_Order
899
900 when Aspect_Bit_Order =>
901 if Is_Record_Type (E)
902 and then No (Get_Attribute_Definition_Clause
903 (E, Attribute_Bit_Order))
904 and then Reverse_Bit_Order (P)
905 then
906 Set_Reverse_Bit_Order (Base_Type (E));
907 end if;
908
909 -- Component_Size
910
911 when Aspect_Component_Size =>
912 if Is_Array_Type (E)
913 and then not Has_Component_Size_Clause (E)
914 then
915 Set_Component_Size
916 (Base_Type (E), Component_Size (P));
917 end if;
918
919 -- Machine_Radix
920
921 when Aspect_Machine_Radix =>
922 if Is_Decimal_Fixed_Point_Type (E)
923 and then not Has_Machine_Radix_Clause (E)
924 then
925 Set_Machine_Radix_10 (E, Machine_Radix_10 (P));
926 end if;
927
928 -- Object_Size (also Size which also sets Object_Size)
929
930 when Aspect_Object_Size | Aspect_Size =>
931 if not Has_Size_Clause (E)
932 and then
933 No (Get_Attribute_Definition_Clause
934 (E, Attribute_Object_Size))
935 then
936 Set_Esize (E, Esize (P));
937 end if;
938
939 -- Pack
940
941 when Aspect_Pack =>
942 if not Is_Packed (E) then
943 Set_Is_Packed (Base_Type (E));
944
945 if Is_Bit_Packed_Array (P) then
946 Set_Is_Bit_Packed_Array (Base_Type (E));
947 Set_Packed_Array_Impl_Type
948 (E, Packed_Array_Impl_Type (P));
949 end if;
950 end if;
951
952 -- Scalar_Storage_Order
953
954 when Aspect_Scalar_Storage_Order =>
955 if (Is_Record_Type (E) or else Is_Array_Type (E))
956 and then No (Get_Attribute_Definition_Clause
957 (E, Attribute_Scalar_Storage_Order))
958 and then Reverse_Storage_Order (P)
959 then
960 Set_Reverse_Storage_Order (Base_Type (E));
961
962 -- Clear default SSO indications, since the aspect
963 -- overrides the default.
964
965 Set_SSO_Set_Low_By_Default (Base_Type (E), False);
966 Set_SSO_Set_High_By_Default (Base_Type (E), False);
967 end if;
968
969 -- Small
970
971 when Aspect_Small =>
972 if Is_Fixed_Point_Type (E)
973 and then not Has_Small_Clause (E)
974 then
975 Set_Small_Value (E, Small_Value (P));
976 end if;
977
978 -- Storage_Size
979
980 when Aspect_Storage_Size =>
981 if (Is_Access_Type (E) or else Is_Task_Type (E))
982 and then not Has_Storage_Size_Clause (E)
983 then
984 Set_Storage_Size_Variable
985 (Base_Type (E), Storage_Size_Variable (P));
986 end if;
987
988 -- Value_Size
989
990 when Aspect_Value_Size =>
991
992 -- Value_Size is never inherited, it is either set by
993 -- default, or it is explicitly set for the derived
994 -- type. So nothing to do here.
995
996 null;
997
998 -- Volatile
999
1000 when Aspect_Volatile =>
1001 if Is_Volatile (P) then
1002 Set_Is_Volatile (E);
1003 end if;
1004
1005 -- Volatile_Full_Access
1006
1007 when Aspect_Volatile_Full_Access =>
1008 if Is_Volatile_Full_Access (P) then
1009 Set_Is_Volatile_Full_Access (E);
1010 end if;
1011
1012 -- Volatile_Components
1013
1014 when Aspect_Volatile_Components =>
1015 if Has_Volatile_Components (P) then
1016 Set_Has_Volatile_Components (Base_Type (E));
1017 end if;
1018
1019 -- That should be all the Rep Aspects
1020
1021 when others =>
1022 pragma Assert (Aspect_Delay (A_Id) /= Rep_Aspect);
1023 null;
1024
1025 end case;
1026 end if;
1027 end if;
1028
1029 N := Next_Rep_Item (N);
1030 end loop;
1031 end Inherit_Delayed_Rep_Aspects;
1032
1033 -------------------------------------
1034 -- Make_Pragma_From_Boolean_Aspect --
1035 -------------------------------------
1036
1037 procedure Make_Pragma_From_Boolean_Aspect (ASN : Node_Id) is
1038 Ident : constant Node_Id := Identifier (ASN);
1039 A_Name : constant Name_Id := Chars (Ident);
1040 A_Id : constant Aspect_Id := Get_Aspect_Id (A_Name);
1041 Ent : constant Entity_Id := Entity (ASN);
1042 Expr : constant Node_Id := Expression (ASN);
1043 Loc : constant Source_Ptr := Sloc (ASN);
1044
1045 procedure Check_False_Aspect_For_Derived_Type;
1046 -- This procedure checks for the case of a false aspect for a derived
1047 -- type, which improperly tries to cancel an aspect inherited from
1048 -- the parent.
1049
1050 -----------------------------------------
1051 -- Check_False_Aspect_For_Derived_Type --
1052 -----------------------------------------
1053
1054 procedure Check_False_Aspect_For_Derived_Type is
1055 Par : Node_Id;
1056
1057 begin
1058 -- We are only checking derived types
1059
1060 if not Is_Derived_Type (E) then
1061 return;
1062 end if;
1063
1064 Par := Nearest_Ancestor (E);
1065
1066 case A_Id is
1067 when Aspect_Atomic | Aspect_Shared =>
1068 if not Is_Atomic (Par) then
1069 return;
1070 end if;
1071
1072 when Aspect_Atomic_Components =>
1073 if not Has_Atomic_Components (Par) then
1074 return;
1075 end if;
1076
1077 when Aspect_Discard_Names =>
1078 if not Discard_Names (Par) then
1079 return;
1080 end if;
1081
1082 when Aspect_Pack =>
1083 if not Is_Packed (Par) then
1084 return;
1085 end if;
1086
1087 when Aspect_Unchecked_Union =>
1088 if not Is_Unchecked_Union (Par) then
1089 return;
1090 end if;
1091
1092 when Aspect_Volatile =>
1093 if not Is_Volatile (Par) then
1094 return;
1095 end if;
1096
1097 when Aspect_Volatile_Components =>
1098 if not Has_Volatile_Components (Par) then
1099 return;
1100 end if;
1101
1102 when Aspect_Volatile_Full_Access =>
1103 if not Is_Volatile_Full_Access (Par) then
1104 return;
1105 end if;
1106
1107 when others =>
1108 return;
1109 end case;
1110
1111 -- Fall through means we are canceling an inherited aspect
1112
1113 Error_Msg_Name_1 := A_Name;
1114 Error_Msg_NE
1115 ("derived type& inherits aspect%, cannot cancel", Expr, E);
1116 end Check_False_Aspect_For_Derived_Type;
1117
1118 -- Local variables
1119
1120 Prag : Node_Id;
1121
1122 -- Start of processing for Make_Pragma_From_Boolean_Aspect
1123
1124 begin
1125 -- Note that we know Expr is present, because for a missing Expr
1126 -- argument, we knew it was True and did not need to delay the
1127 -- evaluation to the freeze point.
1128
1129 if Is_False (Static_Boolean (Expr)) then
1130 Check_False_Aspect_For_Derived_Type;
1131
1132 else
1133 Prag :=
1134 Make_Pragma (Loc,
1135 Pragma_Identifier =>
1136 Make_Identifier (Sloc (Ident), Chars (Ident)),
1137 Pragma_Argument_Associations => New_List (
1138 Make_Pragma_Argument_Association (Sloc (Ident),
1139 Expression => New_Occurrence_Of (Ent, Sloc (Ident)))));
1140
1141 Set_From_Aspect_Specification (Prag, True);
1142 Set_Corresponding_Aspect (Prag, ASN);
1143 Set_Aspect_Rep_Item (ASN, Prag);
1144 Set_Is_Delayed_Aspect (Prag);
1145 Set_Parent (Prag, ASN);
1146 end if;
1147 end Make_Pragma_From_Boolean_Aspect;
1148
1149 -- Local variables
1150
1151 A_Id : Aspect_Id;
1152 ASN : Node_Id;
1153 Ritem : Node_Id;
1154
1155 -- Start of processing for Analyze_Aspects_At_Freeze_Point
1156
1157 begin
1158 -- Must be visible in current scope
1159
1160 if not Scope_Within_Or_Same (Current_Scope, Scope (E)) then
1161 return;
1162 end if;
1163
1164 -- Look for aspect specification entries for this entity
1165
1166 ASN := First_Rep_Item (E);
1167 while Present (ASN) loop
1168 if Nkind (ASN) = N_Aspect_Specification then
1169 exit when Entity (ASN) /= E;
1170
1171 if Is_Delayed_Aspect (ASN) then
1172 A_Id := Get_Aspect_Id (ASN);
1173
1174 case A_Id is
1175
1176 -- For aspects whose expression is an optional Boolean, make
1177 -- the corresponding pragma at the freeze point.
1178
1179 when Boolean_Aspects |
1180 Library_Unit_Aspects =>
1181
1182 -- Aspects Export and Import require special handling.
1183 -- Both are by definition Boolean and may benefit from
1184 -- forward references, however their expressions are
1185 -- treated as static. In addition, the syntax of their
1186 -- corresponding pragmas requires extra "pieces" which
1187 -- may also contain forward references. To account for
1188 -- all of this, the corresponding pragma is created by
1189 -- Analyze_Aspect_Export_Import, but is not analyzed as
1190 -- the complete analysis must happen now.
1191
1192 if A_Id = Aspect_Export or else A_Id = Aspect_Import then
1193 null;
1194
1195 -- Otherwise create a corresponding pragma
1196
1197 else
1198 Make_Pragma_From_Boolean_Aspect (ASN);
1199 end if;
1200
1201 -- Special handling for aspects that don't correspond to
1202 -- pragmas/attributes.
1203
1204 when Aspect_Default_Value |
1205 Aspect_Default_Component_Value =>
1206
1207 -- Do not inherit aspect for anonymous base type of a
1208 -- scalar or array type, because they apply to the first
1209 -- subtype of the type, and will be processed when that
1210 -- first subtype is frozen.
1211
1212 if Is_Derived_Type (E)
1213 and then not Comes_From_Source (E)
1214 and then E /= First_Subtype (E)
1215 then
1216 null;
1217 else
1218 Analyze_Aspect_Default_Value (ASN);
1219 end if;
1220
1221 -- Ditto for iterator aspects, because the corresponding
1222 -- attributes may not have been analyzed yet.
1223
1224 when Aspect_Constant_Indexing |
1225 Aspect_Variable_Indexing |
1226 Aspect_Default_Iterator |
1227 Aspect_Iterator_Element =>
1228 Analyze (Expression (ASN));
1229
1230 if Etype (Expression (ASN)) = Any_Type then
1231 Error_Msg_NE
1232 ("\aspect must be fully defined before & is frozen",
1233 ASN, E);
1234 end if;
1235
1236 when Aspect_Iterable =>
1237 Validate_Iterable_Aspect (E, ASN);
1238
1239 when others =>
1240 null;
1241 end case;
1242
1243 Ritem := Aspect_Rep_Item (ASN);
1244
1245 if Present (Ritem) then
1246 Analyze (Ritem);
1247 end if;
1248 end if;
1249 end if;
1250
1251 Next_Rep_Item (ASN);
1252 end loop;
1253
1254 -- This is where we inherit delayed rep aspects from our parent. Note
1255 -- that if we fell out of the above loop with ASN non-empty, it means
1256 -- we hit an aspect for an entity other than E, and it must be the
1257 -- type from which we were derived.
1258
1259 if May_Inherit_Delayed_Rep_Aspects (E) then
1260 Inherit_Delayed_Rep_Aspects (ASN);
1261 end if;
1262 end Analyze_Aspects_At_Freeze_Point;
1263
1264 -----------------------------------
1265 -- Analyze_Aspect_Specifications --
1266 -----------------------------------
1267
1268 procedure Analyze_Aspect_Specifications (N : Node_Id; E : Entity_Id) is
1269 procedure Decorate (Asp : Node_Id; Prag : Node_Id);
1270 -- Establish linkages between an aspect and its corresponding pragma
1271
1272 procedure Insert_Pragma
1273 (Prag : Node_Id;
1274 Is_Instance : Boolean := False);
1275 -- Subsidiary to the analysis of aspects
1276 -- Abstract_State
1277 -- Attach_Handler
1278 -- Contract_Cases
1279 -- Depends
1280 -- Ghost
1281 -- Global
1282 -- Initial_Condition
1283 -- Initializes
1284 -- Post
1285 -- Pre
1286 -- Refined_Depends
1287 -- Refined_Global
1288 -- Refined_State
1289 -- SPARK_Mode
1290 -- Warnings
1291 -- Insert pragma Prag such that it mimics the placement of a source
1292 -- pragma of the same kind. Flag Is_Generic should be set when the
1293 -- context denotes a generic instance.
1294
1295 --------------
1296 -- Decorate --
1297 --------------
1298
1299 procedure Decorate (Asp : Node_Id; Prag : Node_Id) is
1300 begin
1301 Set_Aspect_Rep_Item (Asp, Prag);
1302 Set_Corresponding_Aspect (Prag, Asp);
1303 Set_From_Aspect_Specification (Prag);
1304 Set_Parent (Prag, Asp);
1305 end Decorate;
1306
1307 -------------------
1308 -- Insert_Pragma --
1309 -------------------
1310
1311 procedure Insert_Pragma
1312 (Prag : Node_Id;
1313 Is_Instance : Boolean := False)
1314 is
1315 Aux : Node_Id;
1316 Decl : Node_Id;
1317 Decls : List_Id;
1318 Def : Node_Id;
1319 Inserted : Boolean := False;
1320
1321 begin
1322 -- When the aspect appears on an entry, package, protected unit,
1323 -- subprogram, or task unit body, insert the generated pragma at the
1324 -- top of the body declarations to emulate the behavior of a source
1325 -- pragma.
1326
1327 -- package body Pack with Aspect is
1328
1329 -- package body Pack is
1330 -- pragma Prag;
1331
1332 if Nkind_In (N, N_Entry_Body,
1333 N_Package_Body,
1334 N_Protected_Body,
1335 N_Subprogram_Body,
1336 N_Task_Body)
1337 then
1338 Decls := Declarations (N);
1339
1340 if No (Decls) then
1341 Decls := New_List;
1342 Set_Declarations (N, Decls);
1343 end if;
1344
1345 Prepend_To (Decls, Prag);
1346
1347 -- When the aspect is associated with a [generic] package declaration
1348 -- insert the generated pragma at the top of the visible declarations
1349 -- to emulate the behavior of a source pragma.
1350
1351 -- package Pack with Aspect is
1352
1353 -- package Pack is
1354 -- pragma Prag;
1355
1356 elsif Nkind_In (N, N_Generic_Package_Declaration,
1357 N_Package_Declaration)
1358 then
1359 Decls := Visible_Declarations (Specification (N));
1360
1361 if No (Decls) then
1362 Decls := New_List;
1363 Set_Visible_Declarations (Specification (N), Decls);
1364 end if;
1365
1366 -- The visible declarations of a generic instance have the
1367 -- following structure:
1368
1369 -- <renamings of generic formals>
1370 -- <renamings of internally-generated spec and body>
1371 -- <first source declaration>
1372
1373 -- Insert the pragma before the first source declaration by
1374 -- skipping the instance "header" to ensure proper visibility of
1375 -- all formals.
1376
1377 if Is_Instance then
1378 Decl := First (Decls);
1379 while Present (Decl) loop
1380 if Comes_From_Source (Decl) then
1381 Insert_Before (Decl, Prag);
1382 Inserted := True;
1383 exit;
1384 else
1385 Next (Decl);
1386 end if;
1387 end loop;
1388
1389 -- The pragma is placed after the instance "header"
1390
1391 if not Inserted then
1392 Append_To (Decls, Prag);
1393 end if;
1394
1395 -- Otherwise this is not a generic instance
1396
1397 else
1398 Prepend_To (Decls, Prag);
1399 end if;
1400
1401 -- When the aspect is associated with a protected unit declaration,
1402 -- insert the generated pragma at the top of the visible declarations
1403 -- the emulate the behavior of a source pragma.
1404
1405 -- protected [type] Prot with Aspect is
1406
1407 -- protected [type] Prot is
1408 -- pragma Prag;
1409
1410 elsif Nkind (N) = N_Protected_Type_Declaration then
1411 Def := Protected_Definition (N);
1412
1413 if No (Def) then
1414 Def :=
1415 Make_Protected_Definition (Sloc (N),
1416 Visible_Declarations => New_List,
1417 End_Label => Empty);
1418
1419 Set_Protected_Definition (N, Def);
1420 end if;
1421
1422 Decls := Visible_Declarations (Def);
1423
1424 if No (Decls) then
1425 Decls := New_List;
1426 Set_Visible_Declarations (Def, Decls);
1427 end if;
1428
1429 Prepend_To (Decls, Prag);
1430
1431 -- When the aspect is associated with a task unit declaration, insert
1432 -- insert the generated pragma at the top of the visible declarations
1433 -- the emulate the behavior of a source pragma.
1434
1435 -- task [type] Prot with Aspect is
1436
1437 -- task [type] Prot is
1438 -- pragma Prag;
1439
1440 elsif Nkind (N) = N_Task_Type_Declaration then
1441 Def := Task_Definition (N);
1442
1443 if No (Def) then
1444 Def :=
1445 Make_Task_Definition (Sloc (N),
1446 Visible_Declarations => New_List,
1447 End_Label => Empty);
1448
1449 Set_Task_Definition (N, Def);
1450 end if;
1451
1452 Decls := Visible_Declarations (Def);
1453
1454 if No (Decls) then
1455 Decls := New_List;
1456 Set_Visible_Declarations (Def, Decls);
1457 end if;
1458
1459 Prepend_To (Decls, Prag);
1460
1461 -- When the context is a library unit, the pragma is added to the
1462 -- Pragmas_After list.
1463
1464 elsif Nkind (Parent (N)) = N_Compilation_Unit then
1465 Aux := Aux_Decls_Node (Parent (N));
1466
1467 if No (Pragmas_After (Aux)) then
1468 Set_Pragmas_After (Aux, New_List);
1469 end if;
1470
1471 Prepend (Prag, Pragmas_After (Aux));
1472
1473 -- Default, the pragma is inserted after the context
1474
1475 else
1476 Insert_After (N, Prag);
1477 end if;
1478 end Insert_Pragma;
1479
1480 -- Local variables
1481
1482 Aspect : Node_Id;
1483 Aitem : Node_Id;
1484 Ent : Node_Id;
1485
1486 L : constant List_Id := Aspect_Specifications (N);
1487
1488 Ins_Node : Node_Id := N;
1489 -- Insert pragmas/attribute definition clause after this node when no
1490 -- delayed analysis is required.
1491
1492 -- Start of processing for Analyze_Aspect_Specifications
1493
1494 begin
1495 -- The general processing involves building an attribute definition
1496 -- clause or a pragma node that corresponds to the aspect. Then in order
1497 -- to delay the evaluation of this aspect to the freeze point, we attach
1498 -- the corresponding pragma/attribute definition clause to the aspect
1499 -- specification node, which is then placed in the Rep Item chain. In
1500 -- this case we mark the entity by setting the flag Has_Delayed_Aspects
1501 -- and we evaluate the rep item at the freeze point. When the aspect
1502 -- doesn't have a corresponding pragma/attribute definition clause, then
1503 -- its analysis is simply delayed at the freeze point.
1504
1505 -- Some special cases don't require delay analysis, thus the aspect is
1506 -- analyzed right now.
1507
1508 -- Note that there is a special handling for Pre, Post, Test_Case,
1509 -- Contract_Cases aspects. In these cases, we do not have to worry
1510 -- about delay issues, since the pragmas themselves deal with delay
1511 -- of visibility for the expression analysis. Thus, we just insert
1512 -- the pragma after the node N.
1513
1514 pragma Assert (Present (L));
1515
1516 -- Loop through aspects
1517
1518 Aspect := First (L);
1519 Aspect_Loop : while Present (Aspect) loop
1520 Analyze_One_Aspect : declare
1521 Expr : constant Node_Id := Expression (Aspect);
1522 Id : constant Node_Id := Identifier (Aspect);
1523 Loc : constant Source_Ptr := Sloc (Aspect);
1524 Nam : constant Name_Id := Chars (Id);
1525 A_Id : constant Aspect_Id := Get_Aspect_Id (Nam);
1526 Anod : Node_Id;
1527
1528 Delay_Required : Boolean;
1529 -- Set False if delay is not required
1530
1531 Eloc : Source_Ptr := No_Location;
1532 -- Source location of expression, modified when we split PPC's. It
1533 -- is set below when Expr is present.
1534
1535 procedure Analyze_Aspect_Convention;
1536 -- Perform analysis of aspect Convention
1537
1538 procedure Analyze_Aspect_Export_Import;
1539 -- Perform analysis of aspects Export or Import
1540
1541 procedure Analyze_Aspect_External_Link_Name;
1542 -- Perform analysis of aspects External_Name or Link_Name
1543
1544 procedure Analyze_Aspect_Implicit_Dereference;
1545 -- Perform analysis of the Implicit_Dereference aspects
1546
1547 procedure Make_Aitem_Pragma
1548 (Pragma_Argument_Associations : List_Id;
1549 Pragma_Name : Name_Id);
1550 -- This is a wrapper for Make_Pragma used for converting aspects
1551 -- to pragmas. It takes care of Sloc (set from Loc) and building
1552 -- the pragma identifier from the given name. In addition the
1553 -- flags Class_Present and Split_PPC are set from the aspect
1554 -- node, as well as Is_Ignored. This routine also sets the
1555 -- From_Aspect_Specification in the resulting pragma node to
1556 -- True, and sets Corresponding_Aspect to point to the aspect.
1557 -- The resulting pragma is assigned to Aitem.
1558
1559 -------------------------------
1560 -- Analyze_Aspect_Convention --
1561 -------------------------------
1562
1563 procedure Analyze_Aspect_Convention is
1564 Conv : Node_Id;
1565 Dummy_1 : Node_Id;
1566 Dummy_2 : Node_Id;
1567 Dummy_3 : Node_Id;
1568 Expo : Node_Id;
1569 Imp : Node_Id;
1570
1571 begin
1572 -- Obtain all interfacing aspects that apply to the related
1573 -- entity.
1574
1575 Get_Interfacing_Aspects
1576 (Iface_Asp => Aspect,
1577 Conv_Asp => Dummy_1,
1578 EN_Asp => Dummy_2,
1579 Expo_Asp => Expo,
1580 Imp_Asp => Imp,
1581 LN_Asp => Dummy_3,
1582 Do_Checks => True);
1583
1584 -- The related entity is subject to aspect Export or Import.
1585 -- Do not process Convention now because it must be analysed
1586 -- as part of Export or Import.
1587
1588 if Present (Expo) or else Present (Imp) then
1589 return;
1590
1591 -- Otherwise Convention appears by itself
1592
1593 else
1594 -- The aspect specifies a particular convention
1595
1596 if Present (Expr) then
1597 Conv := New_Copy_Tree (Expr);
1598
1599 -- Otherwise assume convention Ada
1600
1601 else
1602 Conv := Make_Identifier (Loc, Name_Ada);
1603 end if;
1604
1605 -- Generate:
1606 -- pragma Convention (<Conv>, <E>);
1607
1608 Make_Aitem_Pragma
1609 (Pragma_Name => Name_Convention,
1610 Pragma_Argument_Associations => New_List (
1611 Make_Pragma_Argument_Association (Loc,
1612 Expression => Conv),
1613 Make_Pragma_Argument_Association (Loc,
1614 Expression => New_Occurrence_Of (E, Loc))));
1615
1616 Decorate (Aspect, Aitem);
1617 Insert_Pragma (Aitem);
1618 end if;
1619 end Analyze_Aspect_Convention;
1620
1621 ----------------------------------
1622 -- Analyze_Aspect_Export_Import --
1623 ----------------------------------
1624
1625 procedure Analyze_Aspect_Export_Import is
1626 Dummy_1 : Node_Id;
1627 Dummy_2 : Node_Id;
1628 Dummy_3 : Node_Id;
1629 Expo : Node_Id;
1630 Imp : Node_Id;
1631
1632 begin
1633 -- Obtain all interfacing aspects that apply to the related
1634 -- entity.
1635
1636 Get_Interfacing_Aspects
1637 (Iface_Asp => Aspect,
1638 Conv_Asp => Dummy_1,
1639 EN_Asp => Dummy_2,
1640 Expo_Asp => Expo,
1641 Imp_Asp => Imp,
1642 LN_Asp => Dummy_3,
1643 Do_Checks => True);
1644
1645 -- The related entity cannot be subject to both aspects Export
1646 -- and Import.
1647
1648 if Present (Expo) and then Present (Imp) then
1649 Error_Msg_N
1650 ("incompatible interfacing aspects given for &", E);
1651 Error_Msg_Sloc := Sloc (Expo);
1652 Error_Msg_N ("\aspect `Export` #", E);
1653 Error_Msg_Sloc := Sloc (Imp);
1654 Error_Msg_N ("\aspect `Import` #", E);
1655 end if;
1656
1657 -- A variable is most likely modified from the outside. Take
1658 -- Take the optimistic approach to avoid spurious errors.
1659
1660 if Ekind (E) = E_Variable then
1661 Set_Never_Set_In_Source (E, False);
1662 end if;
1663
1664 -- Resolve the expression of an Import or Export here, and
1665 -- require it to be of type Boolean and static. This is not
1666 -- quite right, because in general this should be delayed,
1667 -- but that seems tricky for these, because normally Boolean
1668 -- aspects are replaced with pragmas at the freeze point in
1669 -- Make_Pragma_From_Boolean_Aspect.
1670
1671 if not Present (Expr)
1672 or else Is_True (Static_Boolean (Expr))
1673 then
1674 if A_Id = Aspect_Import then
1675 Set_Has_Completion (E);
1676 Set_Is_Imported (E);
1677
1678 -- An imported object cannot be explicitly initialized
1679
1680 if Nkind (N) = N_Object_Declaration
1681 and then Present (Expression (N))
1682 then
1683 Error_Msg_N
1684 ("imported entities cannot be initialized "
1685 & "(RM B.1(24))", Expression (N));
1686 end if;
1687
1688 else
1689 pragma Assert (A_Id = Aspect_Export);
1690 Set_Is_Exported (E);
1691 end if;
1692
1693 -- Create the proper form of pragma Export or Import taking
1694 -- into account Conversion, External_Name, and Link_Name.
1695
1696 Aitem := Build_Export_Import_Pragma (Aspect, E);
1697
1698 -- Otherwise the expression is either False or erroneous. There
1699 -- is no corresponding pragma.
1700
1701 else
1702 Aitem := Empty;
1703 end if;
1704 end Analyze_Aspect_Export_Import;
1705
1706 ---------------------------------------
1707 -- Analyze_Aspect_External_Link_Name --
1708 ---------------------------------------
1709
1710 procedure Analyze_Aspect_External_Link_Name is
1711 Dummy_1 : Node_Id;
1712 Dummy_2 : Node_Id;
1713 Dummy_3 : Node_Id;
1714 Expo : Node_Id;
1715 Imp : Node_Id;
1716
1717 begin
1718 -- Obtain all interfacing aspects that apply to the related
1719 -- entity.
1720
1721 Get_Interfacing_Aspects
1722 (Iface_Asp => Aspect,
1723 Conv_Asp => Dummy_1,
1724 EN_Asp => Dummy_2,
1725 Expo_Asp => Expo,
1726 Imp_Asp => Imp,
1727 LN_Asp => Dummy_3,
1728 Do_Checks => True);
1729
1730 -- Ensure that aspect External_Name applies to aspect Export or
1731 -- Import.
1732
1733 if A_Id = Aspect_External_Name then
1734 if No (Expo) and then No (Imp) then
1735 Error_Msg_N
1736 ("aspect `External_Name` requires aspect `Import` or "
1737 & "`Export`", Aspect);
1738 end if;
1739
1740 -- Otherwise ensure that aspect Link_Name applies to aspect
1741 -- Export or Import.
1742
1743 else
1744 pragma Assert (A_Id = Aspect_Link_Name);
1745 if No (Expo) and then No (Imp) then
1746 Error_Msg_N
1747 ("aspect `Link_Name` requires aspect `Import` or "
1748 & "`Export`", Aspect);
1749 end if;
1750 end if;
1751 end Analyze_Aspect_External_Link_Name;
1752
1753 -----------------------------------------
1754 -- Analyze_Aspect_Implicit_Dereference --
1755 -----------------------------------------
1756
1757 procedure Analyze_Aspect_Implicit_Dereference is
1758 Disc : Entity_Id;
1759 Parent_Disc : Entity_Id;
1760
1761 begin
1762 if not Is_Type (E) or else not Has_Discriminants (E) then
1763 Error_Msg_N
1764 ("aspect must apply to a type with discriminants", Expr);
1765
1766 elsif not Is_Entity_Name (Expr) then
1767 Error_Msg_N
1768 ("aspect must name a discriminant of current type", Expr);
1769
1770 else
1771 Disc := First_Discriminant (E);
1772 while Present (Disc) loop
1773 if Chars (Expr) = Chars (Disc)
1774 and then Ekind (Etype (Disc)) =
1775 E_Anonymous_Access_Type
1776 then
1777 Set_Has_Implicit_Dereference (E);
1778 Set_Has_Implicit_Dereference (Disc);
1779 exit;
1780 end if;
1781
1782 Next_Discriminant (Disc);
1783 end loop;
1784
1785 -- Error if no proper access discriminant
1786
1787 if No (Disc) then
1788 Error_Msg_NE ("not an access discriminant of&", Expr, E);
1789 return;
1790 end if;
1791 end if;
1792
1793 -- For a type extension, check whether parent has a
1794 -- reference discriminant, to verify that use is proper.
1795
1796 if Is_Derived_Type (E)
1797 and then Has_Discriminants (Etype (E))
1798 then
1799 Parent_Disc := Get_Reference_Discriminant (Etype (E));
1800
1801 if Present (Parent_Disc)
1802 and then Corresponding_Discriminant (Disc) /= Parent_Disc
1803 then
1804 Error_Msg_N
1805 ("reference discriminant does not match discriminant "
1806 & "of parent type", Expr);
1807 end if;
1808 end if;
1809 end Analyze_Aspect_Implicit_Dereference;
1810
1811 -----------------------
1812 -- Make_Aitem_Pragma --
1813 -----------------------
1814
1815 procedure Make_Aitem_Pragma
1816 (Pragma_Argument_Associations : List_Id;
1817 Pragma_Name : Name_Id)
1818 is
1819 Args : List_Id := Pragma_Argument_Associations;
1820
1821 begin
1822 -- We should never get here if aspect was disabled
1823
1824 pragma Assert (not Is_Disabled (Aspect));
1825
1826 -- Certain aspects allow for an optional name or expression. Do
1827 -- not generate a pragma with empty argument association list.
1828
1829 if No (Args) or else No (Expression (First (Args))) then
1830 Args := No_List;
1831 end if;
1832
1833 -- Build the pragma
1834
1835 Aitem :=
1836 Make_Pragma (Loc,
1837 Pragma_Argument_Associations => Args,
1838 Pragma_Identifier =>
1839 Make_Identifier (Sloc (Id), Pragma_Name),
1840 Class_Present => Class_Present (Aspect),
1841 Split_PPC => Split_PPC (Aspect));
1842
1843 -- Set additional semantic fields
1844
1845 if Is_Ignored (Aspect) then
1846 Set_Is_Ignored (Aitem);
1847 elsif Is_Checked (Aspect) then
1848 Set_Is_Checked (Aitem);
1849 end if;
1850
1851 Set_Corresponding_Aspect (Aitem, Aspect);
1852 Set_From_Aspect_Specification (Aitem);
1853 end Make_Aitem_Pragma;
1854
1855 -- Start of processing for Analyze_One_Aspect
1856
1857 begin
1858 -- Skip aspect if already analyzed, to avoid looping in some cases
1859
1860 if Analyzed (Aspect) then
1861 goto Continue;
1862 end if;
1863
1864 -- Skip looking at aspect if it is totally disabled. Just mark it
1865 -- as such for later reference in the tree. This also sets the
1866 -- Is_Ignored and Is_Checked flags appropriately.
1867
1868 Check_Applicable_Policy (Aspect);
1869
1870 if Is_Disabled (Aspect) then
1871 goto Continue;
1872 end if;
1873
1874 -- Set the source location of expression, used in the case of
1875 -- a failed precondition/postcondition or invariant. Note that
1876 -- the source location of the expression is not usually the best
1877 -- choice here. For example, it gets located on the last AND
1878 -- keyword in a chain of boolean expressiond AND'ed together.
1879 -- It is best to put the message on the first character of the
1880 -- assertion, which is the effect of the First_Node call here.
1881
1882 if Present (Expr) then
1883 Eloc := Sloc (First_Node (Expr));
1884 end if;
1885
1886 -- Check restriction No_Implementation_Aspect_Specifications
1887
1888 if Implementation_Defined_Aspect (A_Id) then
1889 Check_Restriction
1890 (No_Implementation_Aspect_Specifications, Aspect);
1891 end if;
1892
1893 -- Check restriction No_Specification_Of_Aspect
1894
1895 Check_Restriction_No_Specification_Of_Aspect (Aspect);
1896
1897 -- Mark aspect analyzed (actual analysis is delayed till later)
1898
1899 Set_Analyzed (Aspect);
1900 Set_Entity (Aspect, E);
1901 Ent := New_Occurrence_Of (E, Sloc (Id));
1902
1903 -- Check for duplicate aspect. Note that the Comes_From_Source
1904 -- test allows duplicate Pre/Post's that we generate internally
1905 -- to escape being flagged here.
1906
1907 if No_Duplicates_Allowed (A_Id) then
1908 Anod := First (L);
1909 while Anod /= Aspect loop
1910 if Comes_From_Source (Aspect)
1911 and then Same_Aspect (A_Id, Get_Aspect_Id (Anod))
1912 then
1913 Error_Msg_Name_1 := Nam;
1914 Error_Msg_Sloc := Sloc (Anod);
1915
1916 -- Case of same aspect specified twice
1917
1918 if Class_Present (Anod) = Class_Present (Aspect) then
1919 if not Class_Present (Anod) then
1920 Error_Msg_NE
1921 ("aspect% for & previously given#",
1922 Id, E);
1923 else
1924 Error_Msg_NE
1925 ("aspect `%''Class` for & previously given#",
1926 Id, E);
1927 end if;
1928 end if;
1929 end if;
1930
1931 Next (Anod);
1932 end loop;
1933 end if;
1934
1935 -- Check some general restrictions on language defined aspects
1936
1937 if not Implementation_Defined_Aspect (A_Id) then
1938 Error_Msg_Name_1 := Nam;
1939
1940 -- Not allowed for renaming declarations. Examine original
1941 -- node because a subprogram renaming may have been rewritten
1942 -- as a body.
1943
1944 if Nkind (Original_Node (N)) in N_Renaming_Declaration then
1945 Error_Msg_N
1946 ("aspect % not allowed for renaming declaration",
1947 Aspect);
1948 end if;
1949
1950 -- Not allowed for formal type declarations
1951
1952 if Nkind (N) = N_Formal_Type_Declaration then
1953 Error_Msg_N
1954 ("aspect % not allowed for formal type declaration",
1955 Aspect);
1956 end if;
1957 end if;
1958
1959 -- Copy expression for later processing by the procedures
1960 -- Check_Aspect_At_[Freeze_Point | End_Of_Declarations]
1961
1962 Set_Entity (Id, New_Copy_Tree (Expr));
1963
1964 -- Set Delay_Required as appropriate to aspect
1965
1966 case Aspect_Delay (A_Id) is
1967 when Always_Delay =>
1968 Delay_Required := True;
1969
1970 when Never_Delay =>
1971 Delay_Required := False;
1972
1973 when Rep_Aspect =>
1974
1975 -- If expression has the form of an integer literal, then
1976 -- do not delay, since we know the value cannot change.
1977 -- This optimization catches most rep clause cases.
1978
1979 -- For Boolean aspects, don't delay if no expression
1980
1981 if A_Id in Boolean_Aspects and then No (Expr) then
1982 Delay_Required := False;
1983
1984 -- For non-Boolean aspects, don't delay if integer literal
1985
1986 elsif A_Id not in Boolean_Aspects
1987 and then Present (Expr)
1988 and then Nkind (Expr) = N_Integer_Literal
1989 then
1990 Delay_Required := False;
1991
1992 -- All other cases are delayed
1993
1994 else
1995 Delay_Required := True;
1996 Set_Has_Delayed_Rep_Aspects (E);
1997 end if;
1998 end case;
1999
2000 -- Processing based on specific aspect
2001
2002 case A_Id is
2003 when Aspect_Unimplemented =>
2004 null; -- ??? temp for now
2005
2006 -- No_Aspect should be impossible
2007
2008 when No_Aspect =>
2009 raise Program_Error;
2010
2011 -- Case 1: Aspects corresponding to attribute definition
2012 -- clauses.
2013
2014 when Aspect_Address |
2015 Aspect_Alignment |
2016 Aspect_Bit_Order |
2017 Aspect_Component_Size |
2018 Aspect_Constant_Indexing |
2019 Aspect_Default_Iterator |
2020 Aspect_Dispatching_Domain |
2021 Aspect_External_Tag |
2022 Aspect_Input |
2023 Aspect_Iterable |
2024 Aspect_Iterator_Element |
2025 Aspect_Machine_Radix |
2026 Aspect_Object_Size |
2027 Aspect_Output |
2028 Aspect_Read |
2029 Aspect_Scalar_Storage_Order |
2030 Aspect_Size |
2031 Aspect_Small |
2032 Aspect_Simple_Storage_Pool |
2033 Aspect_Storage_Pool |
2034 Aspect_Stream_Size |
2035 Aspect_Value_Size |
2036 Aspect_Variable_Indexing |
2037 Aspect_Write =>
2038
2039 -- Indexing aspects apply only to tagged type
2040
2041 if (A_Id = Aspect_Constant_Indexing
2042 or else
2043 A_Id = Aspect_Variable_Indexing)
2044 and then not (Is_Type (E)
2045 and then Is_Tagged_Type (E))
2046 then
2047 Error_Msg_N
2048 ("indexing aspect can only apply to a tagged type",
2049 Aspect);
2050 goto Continue;
2051 end if;
2052
2053 -- For the case of aspect Address, we don't consider that we
2054 -- know the entity is never set in the source, since it is
2055 -- is likely aliasing is occurring.
2056
2057 -- Note: one might think that the analysis of the resulting
2058 -- attribute definition clause would take care of that, but
2059 -- that's not the case since it won't be from source.
2060
2061 if A_Id = Aspect_Address then
2062 Set_Never_Set_In_Source (E, False);
2063 end if;
2064
2065 -- Correctness of the profile of a stream operation is
2066 -- verified at the freeze point, but we must detect the
2067 -- illegal specification of this aspect for a subtype now,
2068 -- to prevent malformed rep_item chains.
2069
2070 if A_Id = Aspect_Input or else
2071 A_Id = Aspect_Output or else
2072 A_Id = Aspect_Read or else
2073 A_Id = Aspect_Write
2074 then
2075 if not Is_First_Subtype (E) then
2076 Error_Msg_N
2077 ("local name must be a first subtype", Aspect);
2078 goto Continue;
2079
2080 -- If stream aspect applies to the class-wide type,
2081 -- the generated attribute definition applies to the
2082 -- class-wide type as well.
2083
2084 elsif Class_Present (Aspect) then
2085 Ent :=
2086 Make_Attribute_Reference (Loc,
2087 Prefix => Ent,
2088 Attribute_Name => Name_Class);
2089 end if;
2090 end if;
2091
2092 -- Construct the attribute definition clause
2093
2094 Aitem :=
2095 Make_Attribute_Definition_Clause (Loc,
2096 Name => Ent,
2097 Chars => Chars (Id),
2098 Expression => Relocate_Node (Expr));
2099
2100 -- If the address is specified, then we treat the entity as
2101 -- referenced, to avoid spurious warnings. This is analogous
2102 -- to what is done with an attribute definition clause, but
2103 -- here we don't want to generate a reference because this
2104 -- is the point of definition of the entity.
2105
2106 if A_Id = Aspect_Address then
2107 Set_Referenced (E);
2108 end if;
2109
2110 -- Case 2: Aspects corresponding to pragmas
2111
2112 -- Case 2a: Aspects corresponding to pragmas with two
2113 -- arguments, where the first argument is a local name
2114 -- referring to the entity, and the second argument is the
2115 -- aspect definition expression.
2116
2117 -- Linker_Section/Suppress/Unsuppress
2118
2119 when Aspect_Linker_Section |
2120 Aspect_Suppress |
2121 Aspect_Unsuppress =>
2122
2123 Make_Aitem_Pragma
2124 (Pragma_Argument_Associations => New_List (
2125 Make_Pragma_Argument_Association (Loc,
2126 Expression => New_Occurrence_Of (E, Loc)),
2127 Make_Pragma_Argument_Association (Sloc (Expr),
2128 Expression => Relocate_Node (Expr))),
2129 Pragma_Name => Chars (Id));
2130
2131 -- Synchronization
2132
2133 -- Corresponds to pragma Implemented, construct the pragma
2134
2135 when Aspect_Synchronization =>
2136 Make_Aitem_Pragma
2137 (Pragma_Argument_Associations => New_List (
2138 Make_Pragma_Argument_Association (Loc,
2139 Expression => New_Occurrence_Of (E, Loc)),
2140 Make_Pragma_Argument_Association (Sloc (Expr),
2141 Expression => Relocate_Node (Expr))),
2142 Pragma_Name => Name_Implemented);
2143
2144 -- Attach_Handler
2145
2146 when Aspect_Attach_Handler =>
2147 Make_Aitem_Pragma
2148 (Pragma_Argument_Associations => New_List (
2149 Make_Pragma_Argument_Association (Sloc (Ent),
2150 Expression => Ent),
2151 Make_Pragma_Argument_Association (Sloc (Expr),
2152 Expression => Relocate_Node (Expr))),
2153 Pragma_Name => Name_Attach_Handler);
2154
2155 -- We need to insert this pragma into the tree to get proper
2156 -- processing and to look valid from a placement viewpoint.
2157
2158 Insert_Pragma (Aitem);
2159 goto Continue;
2160
2161 -- Dynamic_Predicate, Predicate, Static_Predicate
2162
2163 when Aspect_Dynamic_Predicate |
2164 Aspect_Predicate |
2165 Aspect_Static_Predicate =>
2166
2167 -- These aspects apply only to subtypes
2168
2169 if not Is_Type (E) then
2170 Error_Msg_N
2171 ("predicate can only be specified for a subtype",
2172 Aspect);
2173 goto Continue;
2174
2175 elsif Is_Incomplete_Type (E) then
2176 Error_Msg_N
2177 ("predicate cannot apply to incomplete view", Aspect);
2178 goto Continue;
2179 end if;
2180
2181 -- Construct the pragma (always a pragma Predicate, with
2182 -- flags recording whether it is static/dynamic). We also
2183 -- set flags recording this in the type itself.
2184
2185 Make_Aitem_Pragma
2186 (Pragma_Argument_Associations => New_List (
2187 Make_Pragma_Argument_Association (Sloc (Ent),
2188 Expression => Ent),
2189 Make_Pragma_Argument_Association (Sloc (Expr),
2190 Expression => Relocate_Node (Expr))),
2191 Pragma_Name => Name_Predicate);
2192
2193 -- Mark type has predicates, and remember what kind of
2194 -- aspect lead to this predicate (we need this to access
2195 -- the right set of check policies later on).
2196
2197 Set_Has_Predicates (E);
2198
2199 if A_Id = Aspect_Dynamic_Predicate then
2200 Set_Has_Dynamic_Predicate_Aspect (E);
2201 elsif A_Id = Aspect_Static_Predicate then
2202 Set_Has_Static_Predicate_Aspect (E);
2203 end if;
2204
2205 -- If the type is private, indicate that its completion
2206 -- has a freeze node, because that is the one that will
2207 -- be visible at freeze time.
2208
2209 if Is_Private_Type (E) and then Present (Full_View (E)) then
2210 Set_Has_Predicates (Full_View (E));
2211
2212 if A_Id = Aspect_Dynamic_Predicate then
2213 Set_Has_Dynamic_Predicate_Aspect (Full_View (E));
2214 elsif A_Id = Aspect_Static_Predicate then
2215 Set_Has_Static_Predicate_Aspect (Full_View (E));
2216 end if;
2217
2218 Set_Has_Delayed_Aspects (Full_View (E));
2219 Ensure_Freeze_Node (Full_View (E));
2220 end if;
2221
2222 -- Predicate_Failure
2223
2224 when Aspect_Predicate_Failure =>
2225
2226 -- This aspect applies only to subtypes
2227
2228 if not Is_Type (E) then
2229 Error_Msg_N
2230 ("predicate can only be specified for a subtype",
2231 Aspect);
2232 goto Continue;
2233
2234 elsif Is_Incomplete_Type (E) then
2235 Error_Msg_N
2236 ("predicate cannot apply to incomplete view", Aspect);
2237 goto Continue;
2238 end if;
2239
2240 -- Construct the pragma
2241
2242 Make_Aitem_Pragma
2243 (Pragma_Argument_Associations => New_List (
2244 Make_Pragma_Argument_Association (Sloc (Ent),
2245 Expression => Ent),
2246 Make_Pragma_Argument_Association (Sloc (Expr),
2247 Expression => Relocate_Node (Expr))),
2248 Pragma_Name => Name_Predicate_Failure);
2249
2250 Set_Has_Predicates (E);
2251
2252 -- If the type is private, indicate that its completion
2253 -- has a freeze node, because that is the one that will
2254 -- be visible at freeze time.
2255
2256 if Is_Private_Type (E) and then Present (Full_View (E)) then
2257 Set_Has_Predicates (Full_View (E));
2258 Set_Has_Delayed_Aspects (Full_View (E));
2259 Ensure_Freeze_Node (Full_View (E));
2260 end if;
2261
2262 -- Case 2b: Aspects corresponding to pragmas with two
2263 -- arguments, where the second argument is a local name
2264 -- referring to the entity, and the first argument is the
2265 -- aspect definition expression.
2266
2267 -- Convention
2268
2269 when Aspect_Convention =>
2270 Analyze_Aspect_Convention;
2271 goto Continue;
2272
2273 -- External_Name, Link_Name
2274
2275 when Aspect_External_Name |
2276 Aspect_Link_Name =>
2277 Analyze_Aspect_External_Link_Name;
2278 goto Continue;
2279
2280 -- CPU, Interrupt_Priority, Priority
2281
2282 -- These three aspects can be specified for a subprogram spec
2283 -- or body, in which case we analyze the expression and export
2284 -- the value of the aspect.
2285
2286 -- Previously, we generated an equivalent pragma for bodies
2287 -- (note that the specs cannot contain these pragmas). The
2288 -- pragma was inserted ahead of local declarations, rather than
2289 -- after the body. This leads to a certain duplication between
2290 -- the processing performed for the aspect and the pragma, but
2291 -- given the straightforward handling required it is simpler
2292 -- to duplicate than to translate the aspect in the spec into
2293 -- a pragma in the declarative part of the body.
2294
2295 when Aspect_CPU |
2296 Aspect_Interrupt_Priority |
2297 Aspect_Priority =>
2298
2299 if Nkind_In (N, N_Subprogram_Body,
2300 N_Subprogram_Declaration)
2301 then
2302 -- Analyze the aspect expression
2303
2304 Analyze_And_Resolve (Expr, Standard_Integer);
2305
2306 -- Interrupt_Priority aspect not allowed for main
2307 -- subprograms. RM D.1 does not forbid this explicitly,
2308 -- but RM J.15.11(6/3) does not permit pragma
2309 -- Interrupt_Priority for subprograms.
2310
2311 if A_Id = Aspect_Interrupt_Priority then
2312 Error_Msg_N
2313 ("Interrupt_Priority aspect cannot apply to "
2314 & "subprogram", Expr);
2315
2316 -- The expression must be static
2317
2318 elsif not Is_OK_Static_Expression (Expr) then
2319 Flag_Non_Static_Expr
2320 ("aspect requires static expression!", Expr);
2321
2322 -- Check whether this is the main subprogram. Issue a
2323 -- warning only if it is obviously not a main program
2324 -- (when it has parameters or when the subprogram is
2325 -- within a package).
2326
2327 elsif Present (Parameter_Specifications
2328 (Specification (N)))
2329 or else not Is_Compilation_Unit (Defining_Entity (N))
2330 then
2331 -- See RM D.1(14/3) and D.16(12/3)
2332
2333 Error_Msg_N
2334 ("aspect applied to subprogram other than the "
2335 & "main subprogram has no effect??", Expr);
2336
2337 -- Otherwise check in range and export the value
2338
2339 -- For the CPU aspect
2340
2341 elsif A_Id = Aspect_CPU then
2342 if Is_In_Range (Expr, RTE (RE_CPU_Range)) then
2343
2344 -- Value is correct so we export the value to make
2345 -- it available at execution time.
2346
2347 Set_Main_CPU
2348 (Main_Unit, UI_To_Int (Expr_Value (Expr)));
2349
2350 else
2351 Error_Msg_N
2352 ("main subprogram CPU is out of range", Expr);
2353 end if;
2354
2355 -- For the Priority aspect
2356
2357 elsif A_Id = Aspect_Priority then
2358 if Is_In_Range (Expr, RTE (RE_Priority)) then
2359
2360 -- Value is correct so we export the value to make
2361 -- it available at execution time.
2362
2363 Set_Main_Priority
2364 (Main_Unit, UI_To_Int (Expr_Value (Expr)));
2365
2366 -- Ignore pragma if Relaxed_RM_Semantics to support
2367 -- other targets/non GNAT compilers.
2368
2369 elsif not Relaxed_RM_Semantics then
2370 Error_Msg_N
2371 ("main subprogram priority is out of range",
2372 Expr);
2373 end if;
2374 end if;
2375
2376 -- Load an arbitrary entity from System.Tasking.Stages
2377 -- or System.Tasking.Restricted.Stages (depending on
2378 -- the supported profile) to make sure that one of these
2379 -- packages is implicitly with'ed, since we need to have
2380 -- the tasking run time active for the pragma Priority to
2381 -- have any effect. Previously we with'ed the package
2382 -- System.Tasking, but this package does not trigger the
2383 -- required initialization of the run-time library.
2384
2385 declare
2386 Discard : Entity_Id;
2387 begin
2388 if Restricted_Profile then
2389 Discard := RTE (RE_Activate_Restricted_Tasks);
2390 else
2391 Discard := RTE (RE_Activate_Tasks);
2392 end if;
2393 end;
2394
2395 -- Handling for these Aspects in subprograms is complete
2396
2397 goto Continue;
2398
2399 -- For tasks pass the aspect as an attribute
2400
2401 else
2402 Aitem :=
2403 Make_Attribute_Definition_Clause (Loc,
2404 Name => Ent,
2405 Chars => Chars (Id),
2406 Expression => Relocate_Node (Expr));
2407 end if;
2408
2409 -- Warnings
2410
2411 when Aspect_Warnings =>
2412 Make_Aitem_Pragma
2413 (Pragma_Argument_Associations => New_List (
2414 Make_Pragma_Argument_Association (Sloc (Expr),
2415 Expression => Relocate_Node (Expr)),
2416 Make_Pragma_Argument_Association (Loc,
2417 Expression => New_Occurrence_Of (E, Loc))),
2418 Pragma_Name => Chars (Id));
2419
2420 Decorate (Aspect, Aitem);
2421 Insert_Pragma (Aitem);
2422 goto Continue;
2423
2424 -- Case 2c: Aspects corresponding to pragmas with three
2425 -- arguments.
2426
2427 -- Invariant aspects have a first argument that references the
2428 -- entity, a second argument that is the expression and a third
2429 -- argument that is an appropriate message.
2430
2431 -- Invariant, Type_Invariant
2432
2433 when Aspect_Invariant |
2434 Aspect_Type_Invariant =>
2435
2436 -- Analysis of the pragma will verify placement legality:
2437 -- an invariant must apply to a private type, or appear in
2438 -- the private part of a spec and apply to a completion.
2439
2440 Make_Aitem_Pragma
2441 (Pragma_Argument_Associations => New_List (
2442 Make_Pragma_Argument_Association (Sloc (Ent),
2443 Expression => Ent),
2444 Make_Pragma_Argument_Association (Sloc (Expr),
2445 Expression => Relocate_Node (Expr))),
2446 Pragma_Name => Name_Invariant);
2447
2448 -- Add message unless exception messages are suppressed
2449
2450 if not Opt.Exception_Locations_Suppressed then
2451 Append_To (Pragma_Argument_Associations (Aitem),
2452 Make_Pragma_Argument_Association (Eloc,
2453 Chars => Name_Message,
2454 Expression =>
2455 Make_String_Literal (Eloc,
2456 Strval => "failed invariant from "
2457 & Build_Location_String (Eloc))));
2458 end if;
2459
2460 -- For Invariant case, insert immediately after the entity
2461 -- declaration. We do not have to worry about delay issues
2462 -- since the pragma processing takes care of this.
2463
2464 Delay_Required := False;
2465
2466 -- Case 2d : Aspects that correspond to a pragma with one
2467 -- argument.
2468
2469 -- Abstract_State
2470
2471 -- Aspect Abstract_State introduces implicit declarations for
2472 -- all state abstraction entities it defines. To emulate this
2473 -- behavior, insert the pragma at the beginning of the visible
2474 -- declarations of the related package so that it is analyzed
2475 -- immediately.
2476
2477 when Aspect_Abstract_State => Abstract_State : declare
2478 Context : Node_Id := N;
2479
2480 begin
2481 -- When aspect Abstract_State appears on a generic package,
2482 -- it is propageted to the package instance. The context in
2483 -- this case is the instance spec.
2484
2485 if Nkind (Context) = N_Package_Instantiation then
2486 Context := Instance_Spec (Context);
2487 end if;
2488
2489 if Nkind_In (Context, N_Generic_Package_Declaration,
2490 N_Package_Declaration)
2491 then
2492 Make_Aitem_Pragma
2493 (Pragma_Argument_Associations => New_List (
2494 Make_Pragma_Argument_Association (Loc,
2495 Expression => Relocate_Node (Expr))),
2496 Pragma_Name => Name_Abstract_State);
2497
2498 Decorate (Aspect, Aitem);
2499 Insert_Pragma
2500 (Prag => Aitem,
2501 Is_Instance =>
2502 Is_Generic_Instance (Defining_Entity (Context)));
2503
2504 else
2505 Error_Msg_NE
2506 ("aspect & must apply to a package declaration",
2507 Aspect, Id);
2508 end if;
2509
2510 goto Continue;
2511 end Abstract_State;
2512
2513 -- Aspect Async_Readers is never delayed because it is
2514 -- equivalent to a source pragma which appears after the
2515 -- related object declaration.
2516
2517 when Aspect_Async_Readers =>
2518 Make_Aitem_Pragma
2519 (Pragma_Argument_Associations => New_List (
2520 Make_Pragma_Argument_Association (Loc,
2521 Expression => Relocate_Node (Expr))),
2522 Pragma_Name => Name_Async_Readers);
2523
2524 Decorate (Aspect, Aitem);
2525 Insert_Pragma (Aitem);
2526 goto Continue;
2527
2528 -- Aspect Async_Writers is never delayed because it is
2529 -- equivalent to a source pragma which appears after the
2530 -- related object declaration.
2531
2532 when Aspect_Async_Writers =>
2533 Make_Aitem_Pragma
2534 (Pragma_Argument_Associations => New_List (
2535 Make_Pragma_Argument_Association (Loc,
2536 Expression => Relocate_Node (Expr))),
2537 Pragma_Name => Name_Async_Writers);
2538
2539 Decorate (Aspect, Aitem);
2540 Insert_Pragma (Aitem);
2541 goto Continue;
2542
2543 -- Aspect Constant_After_Elaboration is never delayed because
2544 -- it is equivalent to a source pragma which appears after the
2545 -- related object declaration.
2546
2547 when Aspect_Constant_After_Elaboration =>
2548 Make_Aitem_Pragma
2549 (Pragma_Argument_Associations => New_List (
2550 Make_Pragma_Argument_Association (Loc,
2551 Expression => Relocate_Node (Expr))),
2552 Pragma_Name =>
2553 Name_Constant_After_Elaboration);
2554
2555 Decorate (Aspect, Aitem);
2556 Insert_Pragma (Aitem);
2557 goto Continue;
2558
2559 -- Aspect Default_Internal_Condition is never delayed because
2560 -- it is equivalent to a source pragma which appears after the
2561 -- related private type. To deal with forward references, the
2562 -- generated pragma is stored in the rep chain of the related
2563 -- private type as types do not carry contracts. The pragma is
2564 -- wrapped inside of a procedure at the freeze point of the
2565 -- private type's full view.
2566
2567 when Aspect_Default_Initial_Condition =>
2568 Make_Aitem_Pragma
2569 (Pragma_Argument_Associations => New_List (
2570 Make_Pragma_Argument_Association (Loc,
2571 Expression => Relocate_Node (Expr))),
2572 Pragma_Name =>
2573 Name_Default_Initial_Condition);
2574
2575 Decorate (Aspect, Aitem);
2576 Insert_Pragma (Aitem);
2577 goto Continue;
2578
2579 -- Default_Storage_Pool
2580
2581 when Aspect_Default_Storage_Pool =>
2582 Make_Aitem_Pragma
2583 (Pragma_Argument_Associations => New_List (
2584 Make_Pragma_Argument_Association (Loc,
2585 Expression => Relocate_Node (Expr))),
2586 Pragma_Name =>
2587 Name_Default_Storage_Pool);
2588
2589 Decorate (Aspect, Aitem);
2590 Insert_Pragma (Aitem);
2591 goto Continue;
2592
2593 -- Depends
2594
2595 -- Aspect Depends is never delayed because it is equivalent to
2596 -- a source pragma which appears after the related subprogram.
2597 -- To deal with forward references, the generated pragma is
2598 -- stored in the contract of the related subprogram and later
2599 -- analyzed at the end of the declarative region. See routine
2600 -- Analyze_Depends_In_Decl_Part for details.
2601
2602 when Aspect_Depends =>
2603 Make_Aitem_Pragma
2604 (Pragma_Argument_Associations => New_List (
2605 Make_Pragma_Argument_Association (Loc,
2606 Expression => Relocate_Node (Expr))),
2607 Pragma_Name => Name_Depends);
2608
2609 Decorate (Aspect, Aitem);
2610 Insert_Pragma (Aitem);
2611 goto Continue;
2612
2613 -- Aspect Effecitve_Reads is never delayed because it is
2614 -- equivalent to a source pragma which appears after the
2615 -- related object declaration.
2616
2617 when Aspect_Effective_Reads =>
2618 Make_Aitem_Pragma
2619 (Pragma_Argument_Associations => New_List (
2620 Make_Pragma_Argument_Association (Loc,
2621 Expression => Relocate_Node (Expr))),
2622 Pragma_Name => Name_Effective_Reads);
2623
2624 Decorate (Aspect, Aitem);
2625 Insert_Pragma (Aitem);
2626 goto Continue;
2627
2628 -- Aspect Effective_Writes is never delayed because it is
2629 -- equivalent to a source pragma which appears after the
2630 -- related object declaration.
2631
2632 when Aspect_Effective_Writes =>
2633 Make_Aitem_Pragma
2634 (Pragma_Argument_Associations => New_List (
2635 Make_Pragma_Argument_Association (Loc,
2636 Expression => Relocate_Node (Expr))),
2637 Pragma_Name => Name_Effective_Writes);
2638
2639 Decorate (Aspect, Aitem);
2640 Insert_Pragma (Aitem);
2641 goto Continue;
2642
2643 -- Aspect Extensions_Visible is never delayed because it is
2644 -- equivalent to a source pragma which appears after the
2645 -- related subprogram.
2646
2647 when Aspect_Extensions_Visible =>
2648 Make_Aitem_Pragma
2649 (Pragma_Argument_Associations => New_List (
2650 Make_Pragma_Argument_Association (Loc,
2651 Expression => Relocate_Node (Expr))),
2652 Pragma_Name => Name_Extensions_Visible);
2653
2654 Decorate (Aspect, Aitem);
2655 Insert_Pragma (Aitem);
2656 goto Continue;
2657
2658 -- Aspect Ghost is never delayed because it is equivalent to a
2659 -- source pragma which appears at the top of [generic] package
2660 -- declarations or after an object, a [generic] subprogram, or
2661 -- a type declaration.
2662
2663 when Aspect_Ghost =>
2664 Make_Aitem_Pragma
2665 (Pragma_Argument_Associations => New_List (
2666 Make_Pragma_Argument_Association (Loc,
2667 Expression => Relocate_Node (Expr))),
2668 Pragma_Name => Name_Ghost);
2669
2670 Decorate (Aspect, Aitem);
2671 Insert_Pragma (Aitem);
2672 goto Continue;
2673
2674 -- Global
2675
2676 -- Aspect Global is never delayed because it is equivalent to
2677 -- a source pragma which appears after the related subprogram.
2678 -- To deal with forward references, the generated pragma is
2679 -- stored in the contract of the related subprogram and later
2680 -- analyzed at the end of the declarative region. See routine
2681 -- Analyze_Global_In_Decl_Part for details.
2682
2683 when Aspect_Global =>
2684 Make_Aitem_Pragma
2685 (Pragma_Argument_Associations => New_List (
2686 Make_Pragma_Argument_Association (Loc,
2687 Expression => Relocate_Node (Expr))),
2688 Pragma_Name => Name_Global);
2689
2690 Decorate (Aspect, Aitem);
2691 Insert_Pragma (Aitem);
2692 goto Continue;
2693
2694 -- Initial_Condition
2695
2696 -- Aspect Initial_Condition is never delayed because it is
2697 -- equivalent to a source pragma which appears after the
2698 -- related package. To deal with forward references, the
2699 -- generated pragma is stored in the contract of the related
2700 -- package and later analyzed at the end of the declarative
2701 -- region. See routine Analyze_Initial_Condition_In_Decl_Part
2702 -- for details.
2703
2704 when Aspect_Initial_Condition => Initial_Condition : declare
2705 Context : Node_Id := N;
2706
2707 begin
2708 -- When aspect Initial_Condition appears on a generic
2709 -- package, it is propageted to the package instance. The
2710 -- context in this case is the instance spec.
2711
2712 if Nkind (Context) = N_Package_Instantiation then
2713 Context := Instance_Spec (Context);
2714 end if;
2715
2716 if Nkind_In (Context, N_Generic_Package_Declaration,
2717 N_Package_Declaration)
2718 then
2719 Make_Aitem_Pragma
2720 (Pragma_Argument_Associations => New_List (
2721 Make_Pragma_Argument_Association (Loc,
2722 Expression => Relocate_Node (Expr))),
2723 Pragma_Name =>
2724 Name_Initial_Condition);
2725
2726 Decorate (Aspect, Aitem);
2727 Insert_Pragma
2728 (Prag => Aitem,
2729 Is_Instance =>
2730 Is_Generic_Instance (Defining_Entity (Context)));
2731
2732 -- Otherwise the context is illegal
2733
2734 else
2735 Error_Msg_NE
2736 ("aspect & must apply to a package declaration",
2737 Aspect, Id);
2738 end if;
2739
2740 goto Continue;
2741 end Initial_Condition;
2742
2743 -- Initializes
2744
2745 -- Aspect Initializes is never delayed because it is equivalent
2746 -- to a source pragma appearing after the related package. To
2747 -- deal with forward references, the generated pragma is stored
2748 -- in the contract of the related package and later analyzed at
2749 -- the end of the declarative region. For details, see routine
2750 -- Analyze_Initializes_In_Decl_Part.
2751
2752 when Aspect_Initializes => Initializes : declare
2753 Context : Node_Id := N;
2754
2755 begin
2756 -- When aspect Initializes appears on a generic package,
2757 -- it is propageted to the package instance. The context
2758 -- in this case is the instance spec.
2759
2760 if Nkind (Context) = N_Package_Instantiation then
2761 Context := Instance_Spec (Context);
2762 end if;
2763
2764 if Nkind_In (Context, N_Generic_Package_Declaration,
2765 N_Package_Declaration)
2766 then
2767 Make_Aitem_Pragma
2768 (Pragma_Argument_Associations => New_List (
2769 Make_Pragma_Argument_Association (Loc,
2770 Expression => Relocate_Node (Expr))),
2771 Pragma_Name => Name_Initializes);
2772
2773 Decorate (Aspect, Aitem);
2774 Insert_Pragma
2775 (Prag => Aitem,
2776 Is_Instance =>
2777 Is_Generic_Instance (Defining_Entity (Context)));
2778
2779 -- Otherwise the context is illegal
2780
2781 else
2782 Error_Msg_NE
2783 ("aspect & must apply to a package declaration",
2784 Aspect, Id);
2785 end if;
2786
2787 goto Continue;
2788 end Initializes;
2789
2790 -- Obsolescent
2791
2792 when Aspect_Obsolescent => declare
2793 Args : List_Id;
2794
2795 begin
2796 if No (Expr) then
2797 Args := No_List;
2798 else
2799 Args := New_List (
2800 Make_Pragma_Argument_Association (Sloc (Expr),
2801 Expression => Relocate_Node (Expr)));
2802 end if;
2803
2804 Make_Aitem_Pragma
2805 (Pragma_Argument_Associations => Args,
2806 Pragma_Name => Chars (Id));
2807 end;
2808
2809 -- Part_Of
2810
2811 when Aspect_Part_Of =>
2812 if Nkind_In (N, N_Object_Declaration,
2813 N_Package_Instantiation)
2814 or else Is_Single_Concurrent_Type_Declaration (N)
2815 then
2816 Make_Aitem_Pragma
2817 (Pragma_Argument_Associations => New_List (
2818 Make_Pragma_Argument_Association (Loc,
2819 Expression => Relocate_Node (Expr))),
2820 Pragma_Name => Name_Part_Of);
2821
2822 Decorate (Aspect, Aitem);
2823 Insert_Pragma (Aitem);
2824
2825 else
2826 Error_Msg_NE
2827 ("aspect & must apply to package instantiation, "
2828 & "object, single protected type or single task type",
2829 Aspect, Id);
2830 end if;
2831
2832 goto Continue;
2833
2834 -- SPARK_Mode
2835
2836 when Aspect_SPARK_Mode =>
2837 Make_Aitem_Pragma
2838 (Pragma_Argument_Associations => New_List (
2839 Make_Pragma_Argument_Association (Loc,
2840 Expression => Relocate_Node (Expr))),
2841 Pragma_Name => Name_SPARK_Mode);
2842
2843 Decorate (Aspect, Aitem);
2844 Insert_Pragma (Aitem);
2845 goto Continue;
2846
2847 -- Refined_Depends
2848
2849 -- Aspect Refined_Depends is never delayed because it is
2850 -- equivalent to a source pragma which appears in the
2851 -- declarations of the related subprogram body. To deal with
2852 -- forward references, the generated pragma is stored in the
2853 -- contract of the related subprogram body and later analyzed
2854 -- at the end of the declarative region. For details, see
2855 -- routine Analyze_Refined_Depends_In_Decl_Part.
2856
2857 when Aspect_Refined_Depends =>
2858 Make_Aitem_Pragma
2859 (Pragma_Argument_Associations => New_List (
2860 Make_Pragma_Argument_Association (Loc,
2861 Expression => Relocate_Node (Expr))),
2862 Pragma_Name => Name_Refined_Depends);
2863
2864 Decorate (Aspect, Aitem);
2865 Insert_Pragma (Aitem);
2866 goto Continue;
2867
2868 -- Refined_Global
2869
2870 -- Aspect Refined_Global is never delayed because it is
2871 -- equivalent to a source pragma which appears in the
2872 -- declarations of the related subprogram body. To deal with
2873 -- forward references, the generated pragma is stored in the
2874 -- contract of the related subprogram body and later analyzed
2875 -- at the end of the declarative region. For details, see
2876 -- routine Analyze_Refined_Global_In_Decl_Part.
2877
2878 when Aspect_Refined_Global =>
2879 Make_Aitem_Pragma
2880 (Pragma_Argument_Associations => New_List (
2881 Make_Pragma_Argument_Association (Loc,
2882 Expression => Relocate_Node (Expr))),
2883 Pragma_Name => Name_Refined_Global);
2884
2885 Decorate (Aspect, Aitem);
2886 Insert_Pragma (Aitem);
2887 goto Continue;
2888
2889 -- Refined_Post
2890
2891 when Aspect_Refined_Post =>
2892 Make_Aitem_Pragma
2893 (Pragma_Argument_Associations => New_List (
2894 Make_Pragma_Argument_Association (Loc,
2895 Expression => Relocate_Node (Expr))),
2896 Pragma_Name => Name_Refined_Post);
2897
2898 Decorate (Aspect, Aitem);
2899 Insert_Pragma (Aitem);
2900 goto Continue;
2901
2902 -- Refined_State
2903
2904 when Aspect_Refined_State =>
2905
2906 -- The corresponding pragma for Refined_State is inserted in
2907 -- the declarations of the related package body. This action
2908 -- synchronizes both the source and from-aspect versions of
2909 -- the pragma.
2910
2911 if Nkind (N) = N_Package_Body then
2912 Make_Aitem_Pragma
2913 (Pragma_Argument_Associations => New_List (
2914 Make_Pragma_Argument_Association (Loc,
2915 Expression => Relocate_Node (Expr))),
2916 Pragma_Name => Name_Refined_State);
2917
2918 Decorate (Aspect, Aitem);
2919 Insert_Pragma (Aitem);
2920
2921 -- Otherwise the context is illegal
2922
2923 else
2924 Error_Msg_NE
2925 ("aspect & must apply to a package body", Aspect, Id);
2926 end if;
2927
2928 goto Continue;
2929
2930 -- Relative_Deadline
2931
2932 when Aspect_Relative_Deadline =>
2933 Make_Aitem_Pragma
2934 (Pragma_Argument_Associations => New_List (
2935 Make_Pragma_Argument_Association (Loc,
2936 Expression => Relocate_Node (Expr))),
2937 Pragma_Name => Name_Relative_Deadline);
2938
2939 -- If the aspect applies to a task, the corresponding pragma
2940 -- must appear within its declarations, not after.
2941
2942 if Nkind (N) = N_Task_Type_Declaration then
2943 declare
2944 Def : Node_Id;
2945 V : List_Id;
2946
2947 begin
2948 if No (Task_Definition (N)) then
2949 Set_Task_Definition (N,
2950 Make_Task_Definition (Loc,
2951 Visible_Declarations => New_List,
2952 End_Label => Empty));
2953 end if;
2954
2955 Def := Task_Definition (N);
2956 V := Visible_Declarations (Def);
2957 if not Is_Empty_List (V) then
2958 Insert_Before (First (V), Aitem);
2959
2960 else
2961 Set_Visible_Declarations (Def, New_List (Aitem));
2962 end if;
2963
2964 goto Continue;
2965 end;
2966 end if;
2967
2968 -- Aspect Volatile_Function is never delayed because it is
2969 -- equivalent to a source pragma which appears after the
2970 -- related subprogram.
2971
2972 when Aspect_Volatile_Function =>
2973 Make_Aitem_Pragma
2974 (Pragma_Argument_Associations => New_List (
2975 Make_Pragma_Argument_Association (Loc,
2976 Expression => Relocate_Node (Expr))),
2977 Pragma_Name => Name_Volatile_Function);
2978
2979 Decorate (Aspect, Aitem);
2980 Insert_Pragma (Aitem);
2981 goto Continue;
2982
2983 -- Case 2e: Annotate aspect
2984
2985 when Aspect_Annotate =>
2986 declare
2987 Args : List_Id;
2988 Pargs : List_Id;
2989 Arg : Node_Id;
2990
2991 begin
2992 -- The argument can be a single identifier
2993
2994 if Nkind (Expr) = N_Identifier then
2995
2996 -- One level of parens is allowed
2997
2998 if Paren_Count (Expr) > 1 then
2999 Error_Msg_F ("extra parentheses ignored", Expr);
3000 end if;
3001
3002 Set_Paren_Count (Expr, 0);
3003
3004 -- Add the single item to the list
3005
3006 Args := New_List (Expr);
3007
3008 -- Otherwise we must have an aggregate
3009
3010 elsif Nkind (Expr) = N_Aggregate then
3011
3012 -- Must be positional
3013
3014 if Present (Component_Associations (Expr)) then
3015 Error_Msg_F
3016 ("purely positional aggregate required", Expr);
3017 goto Continue;
3018 end if;
3019
3020 -- Must not be parenthesized
3021
3022 if Paren_Count (Expr) /= 0 then
3023 Error_Msg_F ("extra parentheses ignored", Expr);
3024 end if;
3025
3026 -- List of arguments is list of aggregate expressions
3027
3028 Args := Expressions (Expr);
3029
3030 -- Anything else is illegal
3031
3032 else
3033 Error_Msg_F ("wrong form for Annotate aspect", Expr);
3034 goto Continue;
3035 end if;
3036
3037 -- Prepare pragma arguments
3038
3039 Pargs := New_List;
3040 Arg := First (Args);
3041 while Present (Arg) loop
3042 Append_To (Pargs,
3043 Make_Pragma_Argument_Association (Sloc (Arg),
3044 Expression => Relocate_Node (Arg)));
3045 Next (Arg);
3046 end loop;
3047
3048 Append_To (Pargs,
3049 Make_Pragma_Argument_Association (Sloc (Ent),
3050 Chars => Name_Entity,
3051 Expression => Ent));
3052
3053 Make_Aitem_Pragma
3054 (Pragma_Argument_Associations => Pargs,
3055 Pragma_Name => Name_Annotate);
3056 end;
3057
3058 -- Case 3 : Aspects that don't correspond to pragma/attribute
3059 -- definition clause.
3060
3061 -- Case 3a: The aspects listed below don't correspond to
3062 -- pragmas/attributes but do require delayed analysis.
3063
3064 -- Default_Value can only apply to a scalar type
3065
3066 when Aspect_Default_Value =>
3067 if not Is_Scalar_Type (E) then
3068 Error_Msg_N
3069 ("aspect Default_Value must apply to a scalar type", N);
3070 end if;
3071
3072 Aitem := Empty;
3073
3074 -- Default_Component_Value can only apply to an array type
3075 -- with scalar components.
3076
3077 when Aspect_Default_Component_Value =>
3078 if not (Is_Array_Type (E)
3079 and then Is_Scalar_Type (Component_Type (E)))
3080 then
3081 Error_Msg_N
3082 ("aspect Default_Component_Value can only apply to an "
3083 & "array of scalar components", N);
3084 end if;
3085
3086 Aitem := Empty;
3087
3088 -- Case 3b: The aspects listed below don't correspond to
3089 -- pragmas/attributes and don't need delayed analysis.
3090
3091 -- Implicit_Dereference
3092
3093 -- For Implicit_Dereference, External_Name and Link_Name, only
3094 -- the legality checks are done during the analysis, thus no
3095 -- delay is required.
3096
3097 when Aspect_Implicit_Dereference =>
3098 Analyze_Aspect_Implicit_Dereference;
3099 goto Continue;
3100
3101 -- Dimension
3102
3103 when Aspect_Dimension =>
3104 Analyze_Aspect_Dimension (N, Id, Expr);
3105 goto Continue;
3106
3107 -- Dimension_System
3108
3109 when Aspect_Dimension_System =>
3110 Analyze_Aspect_Dimension_System (N, Id, Expr);
3111 goto Continue;
3112
3113 -- Case 4: Aspects requiring special handling
3114
3115 -- Pre/Post/Test_Case/Contract_Cases whose corresponding
3116 -- pragmas take care of the delay.
3117
3118 -- Pre/Post
3119
3120 -- Aspects Pre/Post generate Precondition/Postcondition pragmas
3121 -- with a first argument that is the expression, and a second
3122 -- argument that is an informative message if the test fails.
3123 -- This is inserted right after the declaration, to get the
3124 -- required pragma placement. The processing for the pragmas
3125 -- takes care of the required delay.
3126
3127 when Pre_Post_Aspects => Pre_Post : declare
3128 Pname : Name_Id;
3129
3130 begin
3131 if A_Id = Aspect_Pre or else A_Id = Aspect_Precondition then
3132 Pname := Name_Precondition;
3133 else
3134 Pname := Name_Postcondition;
3135 end if;
3136
3137 -- Check that the class-wide predicate cannot be applied to
3138 -- an operation of a synchronized type that is not a tagged
3139 -- type. Other legality checks are performed when analyzing
3140 -- the contract of the operation.
3141
3142 if Class_Present (Aspect)
3143 and then Is_Concurrent_Type (Current_Scope)
3144 and then not Is_Tagged_Type (Current_Scope)
3145 and then Ekind_In (E, E_Entry, E_Function, E_Procedure)
3146 then
3147 Error_Msg_Name_1 := Original_Aspect_Pragma_Name (Aspect);
3148 Error_Msg_N
3149 ("aspect % can only be specified for a primitive "
3150 & "operation of a tagged type", Aspect);
3151
3152 goto Continue;
3153 end if;
3154
3155 -- If the expressions is of the form A and then B, then
3156 -- we generate separate Pre/Post aspects for the separate
3157 -- clauses. Since we allow multiple pragmas, there is no
3158 -- problem in allowing multiple Pre/Post aspects internally.
3159 -- These should be treated in reverse order (B first and
3160 -- A second) since they are later inserted just after N in
3161 -- the order they are treated. This way, the pragma for A
3162 -- ends up preceding the pragma for B, which may have an
3163 -- importance for the error raised (either constraint error
3164 -- or precondition error).
3165
3166 -- We do not do this for Pre'Class, since we have to put
3167 -- these conditions together in a complex OR expression.
3168
3169 -- We do not do this in ASIS mode, as ASIS relies on the
3170 -- original node representing the complete expression, when
3171 -- retrieving it through the source aspect table.
3172
3173 if not ASIS_Mode
3174 and then (Pname = Name_Postcondition
3175 or else not Class_Present (Aspect))
3176 then
3177 while Nkind (Expr) = N_And_Then loop
3178 Insert_After (Aspect,
3179 Make_Aspect_Specification (Sloc (Left_Opnd (Expr)),
3180 Identifier => Identifier (Aspect),
3181 Expression => Relocate_Node (Left_Opnd (Expr)),
3182 Class_Present => Class_Present (Aspect),
3183 Split_PPC => True));
3184 Rewrite (Expr, Relocate_Node (Right_Opnd (Expr)));
3185 Eloc := Sloc (Expr);
3186 end loop;
3187 end if;
3188
3189 -- Build the precondition/postcondition pragma
3190
3191 -- Add note about why we do NOT need Copy_Tree here???
3192
3193 Make_Aitem_Pragma
3194 (Pragma_Argument_Associations => New_List (
3195 Make_Pragma_Argument_Association (Eloc,
3196 Chars => Name_Check,
3197 Expression => Relocate_Node (Expr))),
3198 Pragma_Name => Pname);
3199
3200 -- Add message unless exception messages are suppressed
3201
3202 if not Opt.Exception_Locations_Suppressed then
3203 Append_To (Pragma_Argument_Associations (Aitem),
3204 Make_Pragma_Argument_Association (Eloc,
3205 Chars => Name_Message,
3206 Expression =>
3207 Make_String_Literal (Eloc,
3208 Strval => "failed "
3209 & Get_Name_String (Pname)
3210 & " from "
3211 & Build_Location_String (Eloc))));
3212 end if;
3213
3214 Set_Is_Delayed_Aspect (Aspect);
3215
3216 -- For Pre/Post cases, insert immediately after the entity
3217 -- declaration, since that is the required pragma placement.
3218 -- Note that for these aspects, we do not have to worry
3219 -- about delay issues, since the pragmas themselves deal
3220 -- with delay of visibility for the expression analysis.
3221
3222 Insert_Pragma (Aitem);
3223
3224 goto Continue;
3225 end Pre_Post;
3226
3227 -- Test_Case
3228
3229 when Aspect_Test_Case => Test_Case : declare
3230 Args : List_Id;
3231 Comp_Expr : Node_Id;
3232 Comp_Assn : Node_Id;
3233 New_Expr : Node_Id;
3234
3235 begin
3236 Args := New_List;
3237
3238 if Nkind (Parent (N)) = N_Compilation_Unit then
3239 Error_Msg_Name_1 := Nam;
3240 Error_Msg_N ("incorrect placement of aspect `%`", E);
3241 goto Continue;
3242 end if;
3243
3244 if Nkind (Expr) /= N_Aggregate then
3245 Error_Msg_Name_1 := Nam;
3246 Error_Msg_NE
3247 ("wrong syntax for aspect `%` for &", Id, E);
3248 goto Continue;
3249 end if;
3250
3251 -- Make pragma expressions refer to the original aspect
3252 -- expressions through the Original_Node link. This is used
3253 -- in semantic analysis for ASIS mode, so that the original
3254 -- expression also gets analyzed.
3255
3256 Comp_Expr := First (Expressions (Expr));
3257 while Present (Comp_Expr) loop
3258 New_Expr := Relocate_Node (Comp_Expr);
3259 Append_To (Args,
3260 Make_Pragma_Argument_Association (Sloc (Comp_Expr),
3261 Expression => New_Expr));
3262 Next (Comp_Expr);
3263 end loop;
3264
3265 Comp_Assn := First (Component_Associations (Expr));
3266 while Present (Comp_Assn) loop
3267 if List_Length (Choices (Comp_Assn)) /= 1
3268 or else
3269 Nkind (First (Choices (Comp_Assn))) /= N_Identifier
3270 then
3271 Error_Msg_Name_1 := Nam;
3272 Error_Msg_NE
3273 ("wrong syntax for aspect `%` for &", Id, E);
3274 goto Continue;
3275 end if;
3276
3277 Append_To (Args,
3278 Make_Pragma_Argument_Association (Sloc (Comp_Assn),
3279 Chars => Chars (First (Choices (Comp_Assn))),
3280 Expression =>
3281 Relocate_Node (Expression (Comp_Assn))));
3282 Next (Comp_Assn);
3283 end loop;
3284
3285 -- Build the test-case pragma
3286
3287 Make_Aitem_Pragma
3288 (Pragma_Argument_Associations => Args,
3289 Pragma_Name => Nam);
3290 end Test_Case;
3291
3292 -- Contract_Cases
3293
3294 when Aspect_Contract_Cases =>
3295 Make_Aitem_Pragma
3296 (Pragma_Argument_Associations => New_List (
3297 Make_Pragma_Argument_Association (Loc,
3298 Expression => Relocate_Node (Expr))),
3299 Pragma_Name => Nam);
3300
3301 Decorate (Aspect, Aitem);
3302 Insert_Pragma (Aitem);
3303 goto Continue;
3304
3305 -- Case 5: Special handling for aspects with an optional
3306 -- boolean argument.
3307
3308 -- In the delayed case, the corresponding pragma cannot be
3309 -- generated yet because the evaluation of the boolean needs
3310 -- to be delayed till the freeze point.
3311
3312 when Boolean_Aspects |
3313 Library_Unit_Aspects =>
3314
3315 Set_Is_Boolean_Aspect (Aspect);
3316
3317 -- Lock_Free aspect only apply to protected objects
3318
3319 if A_Id = Aspect_Lock_Free then
3320 if Ekind (E) /= E_Protected_Type then
3321 Error_Msg_Name_1 := Nam;
3322 Error_Msg_N
3323 ("aspect % only applies to a protected object",
3324 Aspect);
3325
3326 else
3327 -- Set the Uses_Lock_Free flag to True if there is no
3328 -- expression or if the expression is True. The
3329 -- evaluation of this aspect should be delayed to the
3330 -- freeze point (why???)
3331
3332 if No (Expr)
3333 or else Is_True (Static_Boolean (Expr))
3334 then
3335 Set_Uses_Lock_Free (E);
3336 end if;
3337
3338 Record_Rep_Item (E, Aspect);
3339 end if;
3340
3341 goto Continue;
3342
3343 elsif A_Id = Aspect_Export or else A_Id = Aspect_Import then
3344 Analyze_Aspect_Export_Import;
3345
3346 -- Disable_Controlled
3347
3348 elsif A_Id = Aspect_Disable_Controlled then
3349 if Ekind (E) /= E_Record_Type
3350 or else not Is_Controlled (E)
3351 then
3352 Error_Msg_N
3353 ("aspect % requires controlled record type", Aspect);
3354 goto Continue;
3355 end if;
3356
3357 -- If we're in a generic template, we don't want to try
3358 -- to disable controlled types, because typical usage is
3359 -- "Disable_Controlled => not <some_check>'Enabled", and
3360 -- the value of Enabled is not known until we see a
3361 -- particular instance. In such a context, we just need
3362 -- to preanalyze the expression for legality.
3363
3364 if Expander_Active then
3365 Analyze_And_Resolve (Expr, Standard_Boolean);
3366
3367 if not Present (Expr)
3368 or else Is_True (Static_Boolean (Expr))
3369 then
3370 Set_Disable_Controlled (E);
3371 end if;
3372
3373 elsif Serious_Errors_Detected = 0 then
3374 Preanalyze_And_Resolve (Expr, Standard_Boolean);
3375 end if;
3376
3377 goto Continue;
3378 end if;
3379
3380 -- Library unit aspects require special handling in the case
3381 -- of a package declaration, the pragma needs to be inserted
3382 -- in the list of declarations for the associated package.
3383 -- There is no issue of visibility delay for these aspects.
3384
3385 if A_Id in Library_Unit_Aspects
3386 and then
3387 Nkind_In (N, N_Package_Declaration,
3388 N_Generic_Package_Declaration)
3389 and then Nkind (Parent (N)) /= N_Compilation_Unit
3390
3391 -- Aspect is legal on a local instantiation of a library-
3392 -- level generic unit.
3393
3394 and then not Is_Generic_Instance (Defining_Entity (N))
3395 then
3396 Error_Msg_N
3397 ("incorrect context for library unit aspect&", Id);
3398 goto Continue;
3399 end if;
3400
3401 -- Cases where we do not delay, includes all cases where the
3402 -- expression is missing other than the above cases.
3403
3404 if not Delay_Required or else No (Expr) then
3405
3406 -- Exclude aspects Export and Import because their pragma
3407 -- syntax does not map directly to a Boolean aspect.
3408
3409 if A_Id /= Aspect_Export
3410 and then A_Id /= Aspect_Import
3411 then
3412 Make_Aitem_Pragma
3413 (Pragma_Argument_Associations => New_List (
3414 Make_Pragma_Argument_Association (Sloc (Ent),
3415 Expression => Ent)),
3416 Pragma_Name => Chars (Id));
3417 end if;
3418
3419 Delay_Required := False;
3420
3421 -- In general cases, the corresponding pragma/attribute
3422 -- definition clause will be inserted later at the freezing
3423 -- point, and we do not need to build it now.
3424
3425 else
3426 Aitem := Empty;
3427 end if;
3428
3429 -- Storage_Size
3430
3431 -- This is special because for access types we need to generate
3432 -- an attribute definition clause. This also works for single
3433 -- task declarations, but it does not work for task type
3434 -- declarations, because we have the case where the expression
3435 -- references a discriminant of the task type. That can't use
3436 -- an attribute definition clause because we would not have
3437 -- visibility on the discriminant. For that case we must
3438 -- generate a pragma in the task definition.
3439
3440 when Aspect_Storage_Size =>
3441
3442 -- Task type case
3443
3444 if Ekind (E) = E_Task_Type then
3445 declare
3446 Decl : constant Node_Id := Declaration_Node (E);
3447
3448 begin
3449 pragma Assert (Nkind (Decl) = N_Task_Type_Declaration);
3450
3451 -- If no task definition, create one
3452
3453 if No (Task_Definition (Decl)) then
3454 Set_Task_Definition (Decl,
3455 Make_Task_Definition (Loc,
3456 Visible_Declarations => Empty_List,
3457 End_Label => Empty));
3458 end if;
3459
3460 -- Create a pragma and put it at the start of the task
3461 -- definition for the task type declaration.
3462
3463 Make_Aitem_Pragma
3464 (Pragma_Argument_Associations => New_List (
3465 Make_Pragma_Argument_Association (Loc,
3466 Expression => Relocate_Node (Expr))),
3467 Pragma_Name => Name_Storage_Size);
3468
3469 Prepend
3470 (Aitem,
3471 Visible_Declarations (Task_Definition (Decl)));
3472 goto Continue;
3473 end;
3474
3475 -- All other cases, generate attribute definition
3476
3477 else
3478 Aitem :=
3479 Make_Attribute_Definition_Clause (Loc,
3480 Name => Ent,
3481 Chars => Chars (Id),
3482 Expression => Relocate_Node (Expr));
3483 end if;
3484 end case;
3485
3486 -- Attach the corresponding pragma/attribute definition clause to
3487 -- the aspect specification node.
3488
3489 if Present (Aitem) then
3490 Set_From_Aspect_Specification (Aitem);
3491 end if;
3492
3493 -- In the context of a compilation unit, we directly put the
3494 -- pragma in the Pragmas_After list of the N_Compilation_Unit_Aux
3495 -- node (no delay is required here) except for aspects on a
3496 -- subprogram body (see below) and a generic package, for which we
3497 -- need to introduce the pragma before building the generic copy
3498 -- (see sem_ch12), and for package instantiations, where the
3499 -- library unit pragmas are better handled early.
3500
3501 if Nkind (Parent (N)) = N_Compilation_Unit
3502 and then (Present (Aitem) or else Is_Boolean_Aspect (Aspect))
3503 then
3504 declare
3505 Aux : constant Node_Id := Aux_Decls_Node (Parent (N));
3506
3507 begin
3508 pragma Assert (Nkind (Aux) = N_Compilation_Unit_Aux);
3509
3510 -- For a Boolean aspect, create the corresponding pragma if
3511 -- no expression or if the value is True.
3512
3513 if Is_Boolean_Aspect (Aspect) and then No (Aitem) then
3514 if Is_True (Static_Boolean (Expr)) then
3515 Make_Aitem_Pragma
3516 (Pragma_Argument_Associations => New_List (
3517 Make_Pragma_Argument_Association (Sloc (Ent),
3518 Expression => Ent)),
3519 Pragma_Name => Chars (Id));
3520
3521 Set_From_Aspect_Specification (Aitem, True);
3522 Set_Corresponding_Aspect (Aitem, Aspect);
3523
3524 else
3525 goto Continue;
3526 end if;
3527 end if;
3528
3529 -- If the aspect is on a subprogram body (relevant aspect
3530 -- is Inline), add the pragma in front of the declarations.
3531
3532 if Nkind (N) = N_Subprogram_Body then
3533 if No (Declarations (N)) then
3534 Set_Declarations (N, New_List);
3535 end if;
3536
3537 Prepend (Aitem, Declarations (N));
3538
3539 elsif Nkind (N) = N_Generic_Package_Declaration then
3540 if No (Visible_Declarations (Specification (N))) then
3541 Set_Visible_Declarations (Specification (N), New_List);
3542 end if;
3543
3544 Prepend (Aitem,
3545 Visible_Declarations (Specification (N)));
3546
3547 elsif Nkind (N) = N_Package_Instantiation then
3548 declare
3549 Spec : constant Node_Id :=
3550 Specification (Instance_Spec (N));
3551 begin
3552 if No (Visible_Declarations (Spec)) then
3553 Set_Visible_Declarations (Spec, New_List);
3554 end if;
3555
3556 Prepend (Aitem, Visible_Declarations (Spec));
3557 end;
3558
3559 else
3560 if No (Pragmas_After (Aux)) then
3561 Set_Pragmas_After (Aux, New_List);
3562 end if;
3563
3564 Append (Aitem, Pragmas_After (Aux));
3565 end if;
3566
3567 goto Continue;
3568 end;
3569 end if;
3570
3571 -- The evaluation of the aspect is delayed to the freezing point.
3572 -- The pragma or attribute clause if there is one is then attached
3573 -- to the aspect specification which is put in the rep item list.
3574
3575 if Delay_Required then
3576 if Present (Aitem) then
3577 Set_Is_Delayed_Aspect (Aitem);
3578 Set_Aspect_Rep_Item (Aspect, Aitem);
3579 Set_Parent (Aitem, Aspect);
3580 end if;
3581
3582 Set_Is_Delayed_Aspect (Aspect);
3583
3584 -- In the case of Default_Value, link the aspect to base type
3585 -- as well, even though it appears on a first subtype. This is
3586 -- mandated by the semantics of the aspect. Do not establish
3587 -- the link when processing the base type itself as this leads
3588 -- to a rep item circularity. Verify that we are dealing with
3589 -- a scalar type to prevent cascaded errors.
3590
3591 if A_Id = Aspect_Default_Value
3592 and then Is_Scalar_Type (E)
3593 and then Base_Type (E) /= E
3594 then
3595 Set_Has_Delayed_Aspects (Base_Type (E));
3596 Record_Rep_Item (Base_Type (E), Aspect);
3597 end if;
3598
3599 Set_Has_Delayed_Aspects (E);
3600 Record_Rep_Item (E, Aspect);
3601
3602 -- When delay is not required and the context is a package or a
3603 -- subprogram body, insert the pragma in the body declarations.
3604
3605 elsif Nkind_In (N, N_Package_Body, N_Subprogram_Body) then
3606 if No (Declarations (N)) then
3607 Set_Declarations (N, New_List);
3608 end if;
3609
3610 -- The pragma is added before source declarations
3611
3612 Prepend_To (Declarations (N), Aitem);
3613
3614 -- When delay is not required and the context is not a compilation
3615 -- unit, we simply insert the pragma/attribute definition clause
3616 -- in sequence.
3617
3618 elsif Present (Aitem) then
3619 Insert_After (Ins_Node, Aitem);
3620 Ins_Node := Aitem;
3621 end if;
3622 end Analyze_One_Aspect;
3623
3624 <<Continue>>
3625 Next (Aspect);
3626 end loop Aspect_Loop;
3627
3628 if Has_Delayed_Aspects (E) then
3629 Ensure_Freeze_Node (E);
3630 end if;
3631 end Analyze_Aspect_Specifications;
3632
3633 ---------------------------------------------------
3634 -- Analyze_Aspect_Specifications_On_Body_Or_Stub --
3635 ---------------------------------------------------
3636
3637 procedure Analyze_Aspect_Specifications_On_Body_Or_Stub (N : Node_Id) is
3638 Body_Id : constant Entity_Id := Defining_Entity (N);
3639
3640 procedure Diagnose_Misplaced_Aspects (Spec_Id : Entity_Id);
3641 -- Body [stub] N has aspects, but they are not properly placed. Emit an
3642 -- error message depending on the aspects involved. Spec_Id denotes the
3643 -- entity of the corresponding spec.
3644
3645 --------------------------------
3646 -- Diagnose_Misplaced_Aspects --
3647 --------------------------------
3648
3649 procedure Diagnose_Misplaced_Aspects (Spec_Id : Entity_Id) is
3650 procedure Misplaced_Aspect_Error
3651 (Asp : Node_Id;
3652 Ref_Nam : Name_Id);
3653 -- Emit an error message concerning misplaced aspect Asp. Ref_Nam is
3654 -- the name of the refined version of the aspect.
3655
3656 ----------------------------
3657 -- Misplaced_Aspect_Error --
3658 ----------------------------
3659
3660 procedure Misplaced_Aspect_Error
3661 (Asp : Node_Id;
3662 Ref_Nam : Name_Id)
3663 is
3664 Asp_Nam : constant Name_Id := Chars (Identifier (Asp));
3665 Asp_Id : constant Aspect_Id := Get_Aspect_Id (Asp_Nam);
3666
3667 begin
3668 -- The corresponding spec already contains the aspect in question
3669 -- and the one appearing on the body must be the refined form:
3670
3671 -- procedure P with Global ...;
3672 -- procedure P with Global ... is ... end P;
3673 -- ^
3674 -- Refined_Global
3675
3676 if Has_Aspect (Spec_Id, Asp_Id) then
3677 Error_Msg_Name_1 := Asp_Nam;
3678
3679 -- Subunits cannot carry aspects that apply to a subprogram
3680 -- declaration.
3681
3682 if Nkind (Parent (N)) = N_Subunit then
3683 Error_Msg_N ("aspect % cannot apply to a subunit", Asp);
3684
3685 -- Otherwise suggest the refined form
3686
3687 else
3688 Error_Msg_Name_2 := Ref_Nam;
3689 Error_Msg_N ("aspect % should be %", Asp);
3690 end if;
3691
3692 -- Otherwise the aspect must appear on the spec, not on the body
3693
3694 -- procedure P;
3695 -- procedure P with Global ... is ... end P;
3696
3697 else
3698 Error_Msg_N
3699 ("aspect specification must appear on initial declaration",
3700 Asp);
3701 end if;
3702 end Misplaced_Aspect_Error;
3703
3704 -- Local variables
3705
3706 Asp : Node_Id;
3707 Asp_Nam : Name_Id;
3708
3709 -- Start of processing for Diagnose_Misplaced_Aspects
3710
3711 begin
3712 -- Iterate over the aspect specifications and emit specific errors
3713 -- where applicable.
3714
3715 Asp := First (Aspect_Specifications (N));
3716 while Present (Asp) loop
3717 Asp_Nam := Chars (Identifier (Asp));
3718
3719 -- Do not emit errors on aspects that can appear on a subprogram
3720 -- body. This scenario occurs when the aspect specification list
3721 -- contains both misplaced and properly placed aspects.
3722
3723 if Aspect_On_Body_Or_Stub_OK (Get_Aspect_Id (Asp_Nam)) then
3724 null;
3725
3726 -- Special diagnostics for SPARK aspects
3727
3728 elsif Asp_Nam = Name_Depends then
3729 Misplaced_Aspect_Error (Asp, Name_Refined_Depends);
3730
3731 elsif Asp_Nam = Name_Global then
3732 Misplaced_Aspect_Error (Asp, Name_Refined_Global);
3733
3734 elsif Asp_Nam = Name_Post then
3735 Misplaced_Aspect_Error (Asp, Name_Refined_Post);
3736
3737 -- Otherwise a language-defined aspect is misplaced
3738
3739 else
3740 Error_Msg_N
3741 ("aspect specification must appear on initial declaration",
3742 Asp);
3743 end if;
3744
3745 Next (Asp);
3746 end loop;
3747 end Diagnose_Misplaced_Aspects;
3748
3749 -- Local variables
3750
3751 Spec_Id : constant Entity_Id := Unique_Defining_Entity (N);
3752
3753 -- Start of processing for Analyze_Aspects_On_Body_Or_Stub
3754
3755 begin
3756 -- Language-defined aspects cannot be associated with a subprogram body
3757 -- [stub] if the subprogram has a spec. Certain implementation defined
3758 -- aspects are allowed to break this rule (for all applicable cases, see
3759 -- table Aspects.Aspect_On_Body_Or_Stub_OK).
3760
3761 if Spec_Id /= Body_Id and then not Aspects_On_Body_Or_Stub_OK (N) then
3762 Diagnose_Misplaced_Aspects (Spec_Id);
3763 else
3764 Analyze_Aspect_Specifications (N, Body_Id);
3765 end if;
3766 end Analyze_Aspect_Specifications_On_Body_Or_Stub;
3767
3768 -----------------------
3769 -- Analyze_At_Clause --
3770 -----------------------
3771
3772 -- An at clause is replaced by the corresponding Address attribute
3773 -- definition clause that is the preferred approach in Ada 95.
3774
3775 procedure Analyze_At_Clause (N : Node_Id) is
3776 CS : constant Boolean := Comes_From_Source (N);
3777
3778 begin
3779 -- This is an obsolescent feature
3780
3781 Check_Restriction (No_Obsolescent_Features, N);
3782
3783 if Warn_On_Obsolescent_Feature then
3784 Error_Msg_N
3785 ("?j?at clause is an obsolescent feature (RM J.7(2))", N);
3786 Error_Msg_N
3787 ("\?j?use address attribute definition clause instead", N);
3788 end if;
3789
3790 -- Rewrite as address clause
3791
3792 Rewrite (N,
3793 Make_Attribute_Definition_Clause (Sloc (N),
3794 Name => Identifier (N),
3795 Chars => Name_Address,
3796 Expression => Expression (N)));
3797
3798 -- We preserve Comes_From_Source, since logically the clause still comes
3799 -- from the source program even though it is changed in form.
3800
3801 Set_Comes_From_Source (N, CS);
3802
3803 -- Analyze rewritten clause
3804
3805 Analyze_Attribute_Definition_Clause (N);
3806 end Analyze_At_Clause;
3807
3808 -----------------------------------------
3809 -- Analyze_Attribute_Definition_Clause --
3810 -----------------------------------------
3811
3812 procedure Analyze_Attribute_Definition_Clause (N : Node_Id) is
3813 Loc : constant Source_Ptr := Sloc (N);
3814 Nam : constant Node_Id := Name (N);
3815 Attr : constant Name_Id := Chars (N);
3816 Expr : constant Node_Id := Expression (N);
3817 Id : constant Attribute_Id := Get_Attribute_Id (Attr);
3818
3819 Ent : Entity_Id;
3820 -- The entity of Nam after it is analyzed. In the case of an incomplete
3821 -- type, this is the underlying type.
3822
3823 U_Ent : Entity_Id;
3824 -- The underlying entity to which the attribute applies. Generally this
3825 -- is the Underlying_Type of Ent, except in the case where the clause
3826 -- applies to full view of incomplete type or private type in which case
3827 -- U_Ent is just a copy of Ent.
3828
3829 FOnly : Boolean := False;
3830 -- Reset to True for subtype specific attribute (Alignment, Size)
3831 -- and for stream attributes, i.e. those cases where in the call to
3832 -- Rep_Item_Too_Late, FOnly is set True so that only the freezing rules
3833 -- are checked. Note that the case of stream attributes is not clear
3834 -- from the RM, but see AI95-00137. Also, the RM seems to disallow
3835 -- Storage_Size for derived task types, but that is also clearly
3836 -- unintentional.
3837
3838 procedure Analyze_Stream_TSS_Definition (TSS_Nam : TSS_Name_Type);
3839 -- Common processing for 'Read, 'Write, 'Input and 'Output attribute
3840 -- definition clauses.
3841
3842 function Duplicate_Clause return Boolean;
3843 -- This routine checks if the aspect for U_Ent being given by attribute
3844 -- definition clause N is for an aspect that has already been specified,
3845 -- and if so gives an error message. If there is a duplicate, True is
3846 -- returned, otherwise if there is no error, False is returned.
3847
3848 procedure Check_Indexing_Functions;
3849 -- Check that the function in Constant_Indexing or Variable_Indexing
3850 -- attribute has the proper type structure. If the name is overloaded,
3851 -- check that some interpretation is legal.
3852
3853 procedure Check_Iterator_Functions;
3854 -- Check that there is a single function in Default_Iterator attribute
3855 -- has the proper type structure.
3856
3857 function Check_Primitive_Function (Subp : Entity_Id) return Boolean;
3858 -- Common legality check for the previous two
3859
3860 -----------------------------------
3861 -- Analyze_Stream_TSS_Definition --
3862 -----------------------------------
3863
3864 procedure Analyze_Stream_TSS_Definition (TSS_Nam : TSS_Name_Type) is
3865 Subp : Entity_Id := Empty;
3866 I : Interp_Index;
3867 It : Interp;
3868 Pnam : Entity_Id;
3869
3870 Is_Read : constant Boolean := (TSS_Nam = TSS_Stream_Read);
3871 -- True for Read attribute, False for other attributes
3872
3873 function Has_Good_Profile
3874 (Subp : Entity_Id;
3875 Report : Boolean := False) return Boolean;
3876 -- Return true if the entity is a subprogram with an appropriate
3877 -- profile for the attribute being defined. If result is False and
3878 -- Report is True, function emits appropriate error.
3879
3880 ----------------------
3881 -- Has_Good_Profile --
3882 ----------------------
3883
3884 function Has_Good_Profile
3885 (Subp : Entity_Id;
3886 Report : Boolean := False) return Boolean
3887 is
3888 Expected_Ekind : constant array (Boolean) of Entity_Kind :=
3889 (False => E_Procedure, True => E_Function);
3890 Is_Function : constant Boolean := (TSS_Nam = TSS_Stream_Input);
3891 F : Entity_Id;
3892 Typ : Entity_Id;
3893
3894 begin
3895 if Ekind (Subp) /= Expected_Ekind (Is_Function) then
3896 return False;
3897 end if;
3898
3899 F := First_Formal (Subp);
3900
3901 if No (F)
3902 or else Ekind (Etype (F)) /= E_Anonymous_Access_Type
3903 or else Designated_Type (Etype (F)) /=
3904 Class_Wide_Type (RTE (RE_Root_Stream_Type))
3905 then
3906 return False;
3907 end if;
3908
3909 if not Is_Function then
3910 Next_Formal (F);
3911
3912 declare
3913 Expected_Mode : constant array (Boolean) of Entity_Kind :=
3914 (False => E_In_Parameter,
3915 True => E_Out_Parameter);
3916 begin
3917 if Parameter_Mode (F) /= Expected_Mode (Is_Read) then
3918 return False;
3919 end if;
3920 end;
3921
3922 Typ := Etype (F);
3923
3924 -- If the attribute specification comes from an aspect
3925 -- specification for a class-wide stream, the parameter must be
3926 -- a class-wide type of the entity to which the aspect applies.
3927
3928 if From_Aspect_Specification (N)
3929 and then Class_Present (Parent (N))
3930 and then Is_Class_Wide_Type (Typ)
3931 then
3932 Typ := Etype (Typ);
3933 end if;
3934
3935 else
3936 Typ := Etype (Subp);
3937 end if;
3938
3939 -- Verify that the prefix of the attribute and the local name for
3940 -- the type of the formal match, or one is the class-wide of the
3941 -- other, in the case of a class-wide stream operation.
3942
3943 if Base_Type (Typ) = Base_Type (Ent)
3944 or else (Is_Class_Wide_Type (Typ)
3945 and then Typ = Class_Wide_Type (Base_Type (Ent)))
3946 or else (Is_Class_Wide_Type (Ent)
3947 and then Ent = Class_Wide_Type (Base_Type (Typ)))
3948 then
3949 null;
3950 else
3951 return False;
3952 end if;
3953
3954 if Present (Next_Formal (F)) then
3955 return False;
3956
3957 elsif not Is_Scalar_Type (Typ)
3958 and then not Is_First_Subtype (Typ)
3959 and then not Is_Class_Wide_Type (Typ)
3960 then
3961 if Report and not Is_First_Subtype (Typ) then
3962 Error_Msg_N
3963 ("subtype of formal in stream operation must be a first "
3964 & "subtype", Parameter_Type (Parent (F)));
3965 end if;
3966
3967 return False;
3968
3969 else
3970 return True;
3971 end if;
3972 end Has_Good_Profile;
3973
3974 -- Start of processing for Analyze_Stream_TSS_Definition
3975
3976 begin
3977 FOnly := True;
3978
3979 if not Is_Type (U_Ent) then
3980 Error_Msg_N ("local name must be a subtype", Nam);
3981 return;
3982
3983 elsif not Is_First_Subtype (U_Ent) then
3984 Error_Msg_N ("local name must be a first subtype", Nam);
3985 return;
3986 end if;
3987
3988 Pnam := TSS (Base_Type (U_Ent), TSS_Nam);
3989
3990 -- If Pnam is present, it can be either inherited from an ancestor
3991 -- type (in which case it is legal to redefine it for this type), or
3992 -- be a previous definition of the attribute for the same type (in
3993 -- which case it is illegal).
3994
3995 -- In the first case, it will have been analyzed already, and we
3996 -- can check that its profile does not match the expected profile
3997 -- for a stream attribute of U_Ent. In the second case, either Pnam
3998 -- has been analyzed (and has the expected profile), or it has not
3999 -- been analyzed yet (case of a type that has not been frozen yet
4000 -- and for which the stream attribute has been set using Set_TSS).
4001
4002 if Present (Pnam)
4003 and then (No (First_Entity (Pnam)) or else Has_Good_Profile (Pnam))
4004 then
4005 Error_Msg_Sloc := Sloc (Pnam);
4006 Error_Msg_Name_1 := Attr;
4007 Error_Msg_N ("% attribute already defined #", Nam);
4008 return;
4009 end if;
4010
4011 Analyze (Expr);
4012
4013 if Is_Entity_Name (Expr) then
4014 if not Is_Overloaded (Expr) then
4015 if Has_Good_Profile (Entity (Expr), Report => True) then
4016 Subp := Entity (Expr);
4017 end if;
4018
4019 else
4020 Get_First_Interp (Expr, I, It);
4021 while Present (It.Nam) loop
4022 if Has_Good_Profile (It.Nam) then
4023 Subp := It.Nam;
4024 exit;
4025 end if;
4026
4027 Get_Next_Interp (I, It);
4028 end loop;
4029 end if;
4030 end if;
4031
4032 if Present (Subp) then
4033 if Is_Abstract_Subprogram (Subp) then
4034 Error_Msg_N ("stream subprogram must not be abstract", Expr);
4035 return;
4036
4037 -- A stream subprogram for an interface type must be a null
4038 -- procedure (RM 13.13.2 (38/3)). Note that the class-wide type
4039 -- of an interface is not an interface type (3.9.4 (6.b/2)).
4040
4041 elsif Is_Interface (U_Ent)
4042 and then not Is_Class_Wide_Type (U_Ent)
4043 and then not Inside_A_Generic
4044 and then
4045 (Ekind (Subp) = E_Function
4046 or else
4047 not Null_Present
4048 (Specification
4049 (Unit_Declaration_Node (Ultimate_Alias (Subp)))))
4050 then
4051 Error_Msg_N
4052 ("stream subprogram for interface type must be null "
4053 & "procedure", Expr);
4054 end if;
4055
4056 Set_Entity (Expr, Subp);
4057 Set_Etype (Expr, Etype (Subp));
4058
4059 New_Stream_Subprogram (N, U_Ent, Subp, TSS_Nam);
4060
4061 else
4062 Error_Msg_Name_1 := Attr;
4063 Error_Msg_N ("incorrect expression for% attribute", Expr);
4064 end if;
4065 end Analyze_Stream_TSS_Definition;
4066
4067 ------------------------------
4068 -- Check_Indexing_Functions --
4069 ------------------------------
4070
4071 procedure Check_Indexing_Functions is
4072 Indexing_Found : Boolean := False;
4073
4074 procedure Check_Inherited_Indexing;
4075 -- For a derived type, check that no indexing aspect is specified
4076 -- for the type if it is also inherited
4077
4078 procedure Check_One_Function (Subp : Entity_Id);
4079 -- Check one possible interpretation. Sets Indexing_Found True if a
4080 -- legal indexing function is found.
4081
4082 procedure Illegal_Indexing (Msg : String);
4083 -- Diagnose illegal indexing function if not overloaded. In the
4084 -- overloaded case indicate that no legal interpretation exists.
4085
4086 ------------------------------
4087 -- Check_Inherited_Indexing --
4088 ------------------------------
4089
4090 procedure Check_Inherited_Indexing is
4091 Inherited : Node_Id;
4092
4093 begin
4094 if Attr = Name_Constant_Indexing then
4095 Inherited :=
4096 Find_Aspect (Etype (Ent), Aspect_Constant_Indexing);
4097 else pragma Assert (Attr = Name_Variable_Indexing);
4098 Inherited :=
4099 Find_Aspect (Etype (Ent), Aspect_Variable_Indexing);
4100 end if;
4101
4102 if Present (Inherited) then
4103 if Debug_Flag_Dot_XX then
4104 null;
4105
4106 -- OK if current attribute_definition_clause is expansion of
4107 -- inherited aspect.
4108
4109 elsif Aspect_Rep_Item (Inherited) = N then
4110 null;
4111
4112 -- Indicate the operation that must be overridden, rather than
4113 -- redefining the indexing aspect.
4114
4115 else
4116 Illegal_Indexing
4117 ("indexing function already inherited from parent type");
4118 Error_Msg_NE
4119 ("!override & instead",
4120 N, Entity (Expression (Inherited)));
4121 end if;
4122 end if;
4123 end Check_Inherited_Indexing;
4124
4125 ------------------------
4126 -- Check_One_Function --
4127 ------------------------
4128
4129 procedure Check_One_Function (Subp : Entity_Id) is
4130 Default_Element : Node_Id;
4131 Ret_Type : constant Entity_Id := Etype (Subp);
4132
4133 begin
4134 if not Is_Overloadable (Subp) then
4135 Illegal_Indexing ("illegal indexing function for type&");
4136 return;
4137
4138 elsif Scope (Subp) /= Scope (Ent) then
4139 if Nkind (Expr) = N_Expanded_Name then
4140
4141 -- Indexing function can't be declared elsewhere
4142
4143 Illegal_Indexing
4144 ("indexing function must be declared in scope of type&");
4145 end if;
4146
4147 return;
4148
4149 elsif No (First_Formal (Subp)) then
4150 Illegal_Indexing
4151 ("Indexing requires a function that applies to type&");
4152 return;
4153
4154 elsif No (Next_Formal (First_Formal (Subp))) then
4155 Illegal_Indexing
4156 ("indexing function must have at least two parameters");
4157 return;
4158
4159 elsif Is_Derived_Type (Ent) then
4160 Check_Inherited_Indexing;
4161 end if;
4162
4163 if not Check_Primitive_Function (Subp) then
4164 Illegal_Indexing
4165 ("Indexing aspect requires a function that applies to type&");
4166 return;
4167 end if;
4168
4169 -- If partial declaration exists, verify that it is not tagged.
4170
4171 if Ekind (Current_Scope) = E_Package
4172 and then Has_Private_Declaration (Ent)
4173 and then From_Aspect_Specification (N)
4174 and then
4175 List_Containing (Parent (Ent)) =
4176 Private_Declarations
4177 (Specification (Unit_Declaration_Node (Current_Scope)))
4178 and then Nkind (N) = N_Attribute_Definition_Clause
4179 then
4180 declare
4181 Decl : Node_Id;
4182
4183 begin
4184 Decl :=
4185 First (Visible_Declarations
4186 (Specification
4187 (Unit_Declaration_Node (Current_Scope))));
4188
4189 while Present (Decl) loop
4190 if Nkind (Decl) = N_Private_Type_Declaration
4191 and then Ent = Full_View (Defining_Identifier (Decl))
4192 and then Tagged_Present (Decl)
4193 and then No (Aspect_Specifications (Decl))
4194 then
4195 Illegal_Indexing
4196 ("Indexing aspect cannot be specified on full view "
4197 & "if partial view is tagged");
4198 return;
4199 end if;
4200
4201 Next (Decl);
4202 end loop;
4203 end;
4204 end if;
4205
4206 -- An indexing function must return either the default element of
4207 -- the container, or a reference type. For variable indexing it
4208 -- must be the latter.
4209
4210 Default_Element :=
4211 Find_Value_Of_Aspect
4212 (Etype (First_Formal (Subp)), Aspect_Iterator_Element);
4213
4214 if Present (Default_Element) then
4215 Analyze (Default_Element);
4216
4217 if Is_Entity_Name (Default_Element)
4218 and then not Covers (Entity (Default_Element), Ret_Type)
4219 and then False
4220 then
4221 Illegal_Indexing
4222 ("wrong return type for indexing function");
4223 return;
4224 end if;
4225 end if;
4226
4227 -- For variable_indexing the return type must be a reference type
4228
4229 if Attr = Name_Variable_Indexing then
4230 if not Has_Implicit_Dereference (Ret_Type) then
4231 Illegal_Indexing
4232 ("variable indexing must return a reference type");
4233 return;
4234
4235 elsif Is_Access_Constant
4236 (Etype (First_Discriminant (Ret_Type)))
4237 then
4238 Illegal_Indexing
4239 ("variable indexing must return an access to variable");
4240 return;
4241 end if;
4242
4243 else
4244 if Has_Implicit_Dereference (Ret_Type)
4245 and then not
4246 Is_Access_Constant (Etype (First_Discriminant (Ret_Type)))
4247 then
4248 Illegal_Indexing
4249 ("constant indexing must return an access to constant");
4250 return;
4251
4252 elsif Is_Access_Type (Etype (First_Formal (Subp)))
4253 and then not Is_Access_Constant (Etype (First_Formal (Subp)))
4254 then
4255 Illegal_Indexing
4256 ("constant indexing must apply to an access to constant");
4257 return;
4258 end if;
4259 end if;
4260
4261 -- All checks succeeded.
4262
4263 Indexing_Found := True;
4264 end Check_One_Function;
4265
4266 -----------------------
4267 -- Illegal_Indexing --
4268 -----------------------
4269
4270 procedure Illegal_Indexing (Msg : String) is
4271 begin
4272 Error_Msg_NE (Msg, N, Ent);
4273 end Illegal_Indexing;
4274
4275 -- Start of processing for Check_Indexing_Functions
4276
4277 begin
4278 if In_Instance then
4279 Check_Inherited_Indexing;
4280 end if;
4281
4282 Analyze (Expr);
4283
4284 if not Is_Overloaded (Expr) then
4285 Check_One_Function (Entity (Expr));
4286
4287 else
4288 declare
4289 I : Interp_Index;
4290 It : Interp;
4291
4292 begin
4293 Indexing_Found := False;
4294 Get_First_Interp (Expr, I, It);
4295 while Present (It.Nam) loop
4296
4297 -- Note that analysis will have added the interpretation
4298 -- that corresponds to the dereference. We only check the
4299 -- subprogram itself.
4300
4301 if Is_Overloadable (It.Nam) then
4302 Check_One_Function (It.Nam);
4303 end if;
4304
4305 Get_Next_Interp (I, It);
4306 end loop;
4307 end;
4308 end if;
4309
4310 if not Indexing_Found and then not Error_Posted (N) then
4311 Error_Msg_NE
4312 ("aspect Indexing requires a local function that "
4313 & "applies to type&", Expr, Ent);
4314 end if;
4315 end Check_Indexing_Functions;
4316
4317 ------------------------------
4318 -- Check_Iterator_Functions --
4319 ------------------------------
4320
4321 procedure Check_Iterator_Functions is
4322 function Valid_Default_Iterator (Subp : Entity_Id) return Boolean;
4323 -- Check one possible interpretation for validity
4324
4325 ----------------------------
4326 -- Valid_Default_Iterator --
4327 ----------------------------
4328
4329 function Valid_Default_Iterator (Subp : Entity_Id) return Boolean is
4330 Root_T : constant Entity_Id := Root_Type (Etype (Etype (Subp)));
4331 Formal : Entity_Id;
4332
4333 begin
4334 if not Check_Primitive_Function (Subp) then
4335 return False;
4336
4337 -- The return type must be derived from a type in an instance
4338 -- of Iterator.Interfaces, and thus its root type must have a
4339 -- predefined name.
4340
4341 elsif Chars (Root_T) /= Name_Forward_Iterator
4342 and then Chars (Root_T) /= Name_Reversible_Iterator
4343 then
4344 return False;
4345
4346 else
4347 Formal := First_Formal (Subp);
4348 end if;
4349
4350 -- False if any subsequent formal has no default expression
4351
4352 Formal := Next_Formal (Formal);
4353 while Present (Formal) loop
4354 if No (Expression (Parent (Formal))) then
4355 return False;
4356 end if;
4357
4358 Next_Formal (Formal);
4359 end loop;
4360
4361 -- True if all subsequent formals have default expressions
4362
4363 return True;
4364 end Valid_Default_Iterator;
4365
4366 -- Start of processing for Check_Iterator_Functions
4367
4368 begin
4369 Analyze (Expr);
4370
4371 if not Is_Entity_Name (Expr) then
4372 Error_Msg_N ("aspect Iterator must be a function name", Expr);
4373 end if;
4374
4375 if not Is_Overloaded (Expr) then
4376 if not Check_Primitive_Function (Entity (Expr)) then
4377 Error_Msg_NE
4378 ("aspect Indexing requires a function that applies to type&",
4379 Entity (Expr), Ent);
4380 end if;
4381
4382 -- Flag the default_iterator as well as the denoted function.
4383
4384 if not Valid_Default_Iterator (Entity (Expr)) then
4385 Error_Msg_N ("improper function for default iterator!", Expr);
4386 end if;
4387
4388 else
4389 declare
4390 Default : Entity_Id := Empty;
4391 I : Interp_Index;
4392 It : Interp;
4393
4394 begin
4395 Get_First_Interp (Expr, I, It);
4396 while Present (It.Nam) loop
4397 if not Check_Primitive_Function (It.Nam)
4398 or else not Valid_Default_Iterator (It.Nam)
4399 then
4400 Remove_Interp (I);
4401
4402 elsif Present (Default) then
4403
4404 -- An explicit one should override an implicit one
4405
4406 if Comes_From_Source (Default) =
4407 Comes_From_Source (It.Nam)
4408 then
4409 Error_Msg_N ("default iterator must be unique", Expr);
4410 Error_Msg_Sloc := Sloc (Default);
4411 Error_Msg_N ("\\possible interpretation#", Expr);
4412 Error_Msg_Sloc := Sloc (It.Nam);
4413 Error_Msg_N ("\\possible interpretation#", Expr);
4414
4415 elsif Comes_From_Source (It.Nam) then
4416 Default := It.Nam;
4417 end if;
4418 else
4419 Default := It.Nam;
4420 end if;
4421
4422 Get_Next_Interp (I, It);
4423 end loop;
4424
4425 if Present (Default) then
4426 Set_Entity (Expr, Default);
4427 Set_Is_Overloaded (Expr, False);
4428 else
4429 Error_Msg_N
4430 ("no interpretation is a valid default iterator!", Expr);
4431 end if;
4432 end;
4433 end if;
4434 end Check_Iterator_Functions;
4435
4436 -------------------------------
4437 -- Check_Primitive_Function --
4438 -------------------------------
4439
4440 function Check_Primitive_Function (Subp : Entity_Id) return Boolean is
4441 Ctrl : Entity_Id;
4442
4443 begin
4444 if Ekind (Subp) /= E_Function then
4445 return False;
4446 end if;
4447
4448 if No (First_Formal (Subp)) then
4449 return False;
4450 else
4451 Ctrl := Etype (First_Formal (Subp));
4452 end if;
4453
4454 -- To be a primitive operation subprogram has to be in same scope.
4455
4456 if Scope (Ctrl) /= Scope (Subp) then
4457 return False;
4458 end if;
4459
4460 -- Type of formal may be the class-wide type, an access to such,
4461 -- or an incomplete view.
4462
4463 if Ctrl = Ent
4464 or else Ctrl = Class_Wide_Type (Ent)
4465 or else
4466 (Ekind (Ctrl) = E_Anonymous_Access_Type
4467 and then (Designated_Type (Ctrl) = Ent
4468 or else
4469 Designated_Type (Ctrl) = Class_Wide_Type (Ent)))
4470 or else
4471 (Ekind (Ctrl) = E_Incomplete_Type
4472 and then Full_View (Ctrl) = Ent)
4473 then
4474 null;
4475 else
4476 return False;
4477 end if;
4478
4479 return True;
4480 end Check_Primitive_Function;
4481
4482 ----------------------
4483 -- Duplicate_Clause --
4484 ----------------------
4485
4486 function Duplicate_Clause return Boolean is
4487 A : Node_Id;
4488
4489 begin
4490 -- Nothing to do if this attribute definition clause comes from
4491 -- an aspect specification, since we could not be duplicating an
4492 -- explicit clause, and we dealt with the case of duplicated aspects
4493 -- in Analyze_Aspect_Specifications.
4494
4495 if From_Aspect_Specification (N) then
4496 return False;
4497 end if;
4498
4499 -- Otherwise current clause may duplicate previous clause, or a
4500 -- previously given pragma or aspect specification for the same
4501 -- aspect.
4502
4503 A := Get_Rep_Item (U_Ent, Chars (N), Check_Parents => False);
4504
4505 if Present (A) then
4506 Error_Msg_Name_1 := Chars (N);
4507 Error_Msg_Sloc := Sloc (A);
4508
4509 Error_Msg_NE ("aspect% for & previously given#", N, U_Ent);
4510 return True;
4511 end if;
4512
4513 return False;
4514 end Duplicate_Clause;
4515
4516 -- Start of processing for Analyze_Attribute_Definition_Clause
4517
4518 begin
4519 -- The following code is a defense against recursion. Not clear that
4520 -- this can happen legitimately, but perhaps some error situations can
4521 -- cause it, and we did see this recursion during testing.
4522
4523 if Analyzed (N) then
4524 return;
4525 else
4526 Set_Analyzed (N, True);
4527 end if;
4528
4529 Check_Restriction_No_Use_Of_Attribute (N);
4530
4531 -- Ignore some selected attributes in CodePeer mode since they are not
4532 -- relevant in this context.
4533
4534 if CodePeer_Mode then
4535 case Id is
4536
4537 -- Ignore Component_Size in CodePeer mode, to avoid changing the
4538 -- internal representation of types by implicitly packing them.
4539
4540 when Attribute_Component_Size =>
4541 Rewrite (N, Make_Null_Statement (Sloc (N)));
4542 return;
4543
4544 when others =>
4545 null;
4546 end case;
4547 end if;
4548
4549 -- Process Ignore_Rep_Clauses option
4550
4551 if Ignore_Rep_Clauses then
4552 case Id is
4553
4554 -- The following should be ignored. They do not affect legality
4555 -- and may be target dependent. The basic idea of -gnatI is to
4556 -- ignore any rep clauses that may be target dependent but do not
4557 -- affect legality (except possibly to be rejected because they
4558 -- are incompatible with the compilation target).
4559
4560 when Attribute_Alignment |
4561 Attribute_Bit_Order |
4562 Attribute_Component_Size |
4563 Attribute_Machine_Radix |
4564 Attribute_Object_Size |
4565 Attribute_Size |
4566 Attribute_Small |
4567 Attribute_Stream_Size |
4568 Attribute_Value_Size =>
4569 Kill_Rep_Clause (N);
4570 return;
4571
4572 -- The following should not be ignored, because in the first place
4573 -- they are reasonably portable, and should not cause problems
4574 -- in compiling code from another target, and also they do affect
4575 -- legality, e.g. failing to provide a stream attribute for a type
4576 -- may make a program illegal.
4577
4578 when Attribute_External_Tag |
4579 Attribute_Input |
4580 Attribute_Output |
4581 Attribute_Read |
4582 Attribute_Simple_Storage_Pool |
4583 Attribute_Storage_Pool |
4584 Attribute_Storage_Size |
4585 Attribute_Write =>
4586 null;
4587
4588 -- We do not do anything here with address clauses, they will be
4589 -- removed by Freeze later on, but for now, it works better to
4590 -- keep then in the tree.
4591
4592 when Attribute_Address =>
4593 null;
4594
4595 -- Other cases are errors ("attribute& cannot be set with
4596 -- definition clause"), which will be caught below.
4597
4598 when others =>
4599 null;
4600 end case;
4601 end if;
4602
4603 Analyze (Nam);
4604 Ent := Entity (Nam);
4605
4606 if Rep_Item_Too_Early (Ent, N) then
4607 return;
4608 end if;
4609
4610 -- Rep clause applies to full view of incomplete type or private type if
4611 -- we have one (if not, this is a premature use of the type). However,
4612 -- certain semantic checks need to be done on the specified entity (i.e.
4613 -- the private view), so we save it in Ent.
4614
4615 if Is_Private_Type (Ent)
4616 and then Is_Derived_Type (Ent)
4617 and then not Is_Tagged_Type (Ent)
4618 and then No (Full_View (Ent))
4619 then
4620 -- If this is a private type whose completion is a derivation from
4621 -- another private type, there is no full view, and the attribute
4622 -- belongs to the type itself, not its underlying parent.
4623
4624 U_Ent := Ent;
4625
4626 elsif Ekind (Ent) = E_Incomplete_Type then
4627
4628 -- The attribute applies to the full view, set the entity of the
4629 -- attribute definition accordingly.
4630
4631 Ent := Underlying_Type (Ent);
4632 U_Ent := Ent;
4633 Set_Entity (Nam, Ent);
4634
4635 else
4636 U_Ent := Underlying_Type (Ent);
4637 end if;
4638
4639 -- Avoid cascaded error
4640
4641 if Etype (Nam) = Any_Type then
4642 return;
4643
4644 -- Must be declared in current scope or in case of an aspect
4645 -- specification, must be visible in current scope.
4646
4647 elsif Scope (Ent) /= Current_Scope
4648 and then
4649 not (From_Aspect_Specification (N)
4650 and then Scope_Within_Or_Same (Current_Scope, Scope (Ent)))
4651 then
4652 Error_Msg_N ("entity must be declared in this scope", Nam);
4653 return;
4654
4655 -- Must not be a source renaming (we do have some cases where the
4656 -- expander generates a renaming, and those cases are OK, in such
4657 -- cases any attribute applies to the renamed object as well).
4658
4659 elsif Is_Object (Ent)
4660 and then Present (Renamed_Object (Ent))
4661 then
4662 -- Case of renamed object from source, this is an error
4663
4664 if Comes_From_Source (Renamed_Object (Ent)) then
4665 Get_Name_String (Chars (N));
4666 Error_Msg_Strlen := Name_Len;
4667 Error_Msg_String (1 .. Name_Len) := Name_Buffer (1 .. Name_Len);
4668 Error_Msg_N
4669 ("~ clause not allowed for a renaming declaration "
4670 & "(RM 13.1(6))", Nam);
4671 return;
4672
4673 -- For the case of a compiler generated renaming, the attribute
4674 -- definition clause applies to the renamed object created by the
4675 -- expander. The easiest general way to handle this is to create a
4676 -- copy of the attribute definition clause for this object.
4677
4678 elsif Is_Entity_Name (Renamed_Object (Ent)) then
4679 Insert_Action (N,
4680 Make_Attribute_Definition_Clause (Loc,
4681 Name =>
4682 New_Occurrence_Of (Entity (Renamed_Object (Ent)), Loc),
4683 Chars => Chars (N),
4684 Expression => Duplicate_Subexpr (Expression (N))));
4685
4686 -- If the renamed object is not an entity, it must be a dereference
4687 -- of an unconstrained function call, and we must introduce a new
4688 -- declaration to capture the expression. This is needed in the case
4689 -- of 'Alignment, where the original declaration must be rewritten.
4690
4691 else
4692 pragma Assert
4693 (Nkind (Renamed_Object (Ent)) = N_Explicit_Dereference);
4694 null;
4695 end if;
4696
4697 -- If no underlying entity, use entity itself, applies to some
4698 -- previously detected error cases ???
4699
4700 elsif No (U_Ent) then
4701 U_Ent := Ent;
4702
4703 -- Cannot specify for a subtype (exception Object/Value_Size)
4704
4705 elsif Is_Type (U_Ent)
4706 and then not Is_First_Subtype (U_Ent)
4707 and then Id /= Attribute_Object_Size
4708 and then Id /= Attribute_Value_Size
4709 and then not From_At_Mod (N)
4710 then
4711 Error_Msg_N ("cannot specify attribute for subtype", Nam);
4712 return;
4713 end if;
4714
4715 Set_Entity (N, U_Ent);
4716
4717 -- Switch on particular attribute
4718
4719 case Id is
4720
4721 -------------
4722 -- Address --
4723 -------------
4724
4725 -- Address attribute definition clause
4726
4727 when Attribute_Address => Address : begin
4728
4729 -- A little error check, catch for X'Address use X'Address;
4730
4731 if Nkind (Nam) = N_Identifier
4732 and then Nkind (Expr) = N_Attribute_Reference
4733 and then Attribute_Name (Expr) = Name_Address
4734 and then Nkind (Prefix (Expr)) = N_Identifier
4735 and then Chars (Nam) = Chars (Prefix (Expr))
4736 then
4737 Error_Msg_NE
4738 ("address for & is self-referencing", Prefix (Expr), Ent);
4739 return;
4740 end if;
4741
4742 -- Not that special case, carry on with analysis of expression
4743
4744 Analyze_And_Resolve (Expr, RTE (RE_Address));
4745
4746 -- Even when ignoring rep clauses we need to indicate that the
4747 -- entity has an address clause and thus it is legal to declare
4748 -- it imported. Freeze will get rid of the address clause later.
4749
4750 if Ignore_Rep_Clauses then
4751 if Ekind_In (U_Ent, E_Variable, E_Constant) then
4752 Record_Rep_Item (U_Ent, N);
4753 end if;
4754
4755 return;
4756 end if;
4757
4758 if Duplicate_Clause then
4759 null;
4760
4761 -- Case of address clause for subprogram
4762
4763 elsif Is_Subprogram (U_Ent) then
4764 if Has_Homonym (U_Ent) then
4765 Error_Msg_N
4766 ("address clause cannot be given for overloaded "
4767 & "subprogram", Nam);
4768 return;
4769 end if;
4770
4771 -- For subprograms, all address clauses are permitted, and we
4772 -- mark the subprogram as having a deferred freeze so that Gigi
4773 -- will not elaborate it too soon.
4774
4775 -- Above needs more comments, what is too soon about???
4776
4777 Set_Has_Delayed_Freeze (U_Ent);
4778
4779 -- Case of address clause for entry
4780
4781 elsif Ekind (U_Ent) = E_Entry then
4782 if Nkind (Parent (N)) = N_Task_Body then
4783 Error_Msg_N
4784 ("entry address must be specified in task spec", Nam);
4785 return;
4786 end if;
4787
4788 -- For entries, we require a constant address
4789
4790 Check_Constant_Address_Clause (Expr, U_Ent);
4791
4792 -- Special checks for task types
4793
4794 if Is_Task_Type (Scope (U_Ent))
4795 and then Comes_From_Source (Scope (U_Ent))
4796 then
4797 Error_Msg_N
4798 ("??entry address declared for entry in task type", N);
4799 Error_Msg_N
4800 ("\??only one task can be declared of this type", N);
4801 end if;
4802
4803 -- Entry address clauses are obsolescent
4804
4805 Check_Restriction (No_Obsolescent_Features, N);
4806
4807 if Warn_On_Obsolescent_Feature then
4808 Error_Msg_N
4809 ("?j?attaching interrupt to task entry is an obsolescent "
4810 & "feature (RM J.7.1)", N);
4811 Error_Msg_N
4812 ("\?j?use interrupt procedure instead", N);
4813 end if;
4814
4815 -- Case of an address clause for a controlled object which we
4816 -- consider to be erroneous.
4817
4818 elsif Is_Controlled (Etype (U_Ent))
4819 or else Has_Controlled_Component (Etype (U_Ent))
4820 then
4821 Error_Msg_NE
4822 ("??controlled object& must not be overlaid", Nam, U_Ent);
4823 Error_Msg_N
4824 ("\??Program_Error will be raised at run time", Nam);
4825 Insert_Action (Declaration_Node (U_Ent),
4826 Make_Raise_Program_Error (Loc,
4827 Reason => PE_Overlaid_Controlled_Object));
4828 return;
4829
4830 -- Case of address clause for a (non-controlled) object
4831
4832 elsif Ekind_In (U_Ent, E_Variable, E_Constant) then
4833 declare
4834 Expr : constant Node_Id := Expression (N);
4835 O_Ent : Entity_Id;
4836 Off : Boolean;
4837
4838 begin
4839 -- Exported variables cannot have an address clause, because
4840 -- this cancels the effect of the pragma Export.
4841
4842 if Is_Exported (U_Ent) then
4843 Error_Msg_N
4844 ("cannot export object with address clause", Nam);
4845 return;
4846 end if;
4847
4848 Find_Overlaid_Entity (N, O_Ent, Off);
4849
4850 if Present (O_Ent) then
4851
4852 -- If the object overlays a constant object, mark it so
4853
4854 if Is_Constant_Object (O_Ent) then
4855 Set_Overlays_Constant (U_Ent);
4856 end if;
4857
4858 -- If the address clause is of the form:
4859
4860 -- for X'Address use Y'Address;
4861
4862 -- or
4863
4864 -- C : constant Address := Y'Address;
4865 -- ...
4866 -- for X'Address use C;
4867
4868 -- then we make an entry in the table to check the size
4869 -- and alignment of the overlaying variable. But we defer
4870 -- this check till after code generation to take full
4871 -- advantage of the annotation done by the back end.
4872
4873 -- If the entity has a generic type, the check will be
4874 -- performed in the instance if the actual type justifies
4875 -- it, and we do not insert the clause in the table to
4876 -- prevent spurious warnings.
4877
4878 -- Note: we used to test Comes_From_Source and only give
4879 -- this warning for source entities, but we have removed
4880 -- this test. It really seems bogus to generate overlays
4881 -- that would trigger this warning in generated code.
4882 -- Furthermore, by removing the test, we handle the
4883 -- aspect case properly.
4884
4885 if Is_Object (O_Ent)
4886 and then not Is_Generic_Type (Etype (U_Ent))
4887 and then Address_Clause_Overlay_Warnings
4888 then
4889 Address_Clause_Checks.Append
4890 ((N, U_Ent, No_Uint, O_Ent, Off));
4891 end if;
4892 else
4893 -- If this is not an overlay, mark a variable as being
4894 -- volatile to prevent unwanted optimizations. It's a
4895 -- conservative interpretation of RM 13.3(19) for the
4896 -- cases where the compiler cannot detect potential
4897 -- aliasing issues easily and it also covers the case
4898 -- of an absolute address where the volatile aspect is
4899 -- kind of implicit.
4900
4901 if Ekind (U_Ent) = E_Variable then
4902 Set_Treat_As_Volatile (U_Ent);
4903 end if;
4904
4905 -- Make an entry in the table for an absolute address as
4906 -- above to check that the value is compatible with the
4907 -- alignment of the object.
4908
4909 declare
4910 Addr : constant Node_Id := Address_Value (Expr);
4911 begin
4912 if Compile_Time_Known_Value (Addr)
4913 and then Address_Clause_Overlay_Warnings
4914 then
4915 Address_Clause_Checks.Append
4916 ((N, U_Ent, Expr_Value (Addr), Empty, False));
4917 end if;
4918 end;
4919 end if;
4920
4921 -- Overlaying controlled objects is erroneous. Emit warning
4922 -- but continue analysis because program is itself legal,
4923 -- and back end must see address clause.
4924
4925 if Present (O_Ent)
4926 and then (Has_Controlled_Component (Etype (O_Ent))
4927 or else Is_Controlled (Etype (O_Ent)))
4928 and then not Inside_A_Generic
4929 then
4930 Error_Msg_N
4931 ("??cannot use overlays with controlled objects", Expr);
4932 Error_Msg_N
4933 ("\??Program_Error will be raised at run time", Expr);
4934 Insert_Action (Declaration_Node (U_Ent),
4935 Make_Raise_Program_Error (Loc,
4936 Reason => PE_Overlaid_Controlled_Object));
4937
4938 -- Issue an unconditional warning for a constant overlaying
4939 -- a variable. For the reverse case, we will issue it only
4940 -- if the variable is modified.
4941
4942 elsif Ekind (U_Ent) = E_Constant
4943 and then Present (O_Ent)
4944 and then not Overlays_Constant (U_Ent)
4945 and then Address_Clause_Overlay_Warnings
4946 then
4947 Error_Msg_N ("??constant overlays a variable", Expr);
4948
4949 -- Imported variables can have an address clause, but then
4950 -- the import is pretty meaningless except to suppress
4951 -- initializations, so we do not need such variables to
4952 -- be statically allocated (and in fact it causes trouble
4953 -- if the address clause is a local value).
4954
4955 elsif Is_Imported (U_Ent) then
4956 Set_Is_Statically_Allocated (U_Ent, False);
4957 end if;
4958
4959 -- We mark a possible modification of a variable with an
4960 -- address clause, since it is likely aliasing is occurring.
4961
4962 Note_Possible_Modification (Nam, Sure => False);
4963
4964 -- Legality checks on the address clause for initialized
4965 -- objects is deferred until the freeze point, because
4966 -- a subsequent pragma might indicate that the object
4967 -- is imported and thus not initialized. Also, the address
4968 -- clause might involve entities that have yet to be
4969 -- elaborated.
4970
4971 Set_Has_Delayed_Freeze (U_Ent);
4972
4973 -- If an initialization call has been generated for this
4974 -- object, it needs to be deferred to after the freeze node
4975 -- we have just now added, otherwise GIGI will see a
4976 -- reference to the variable (as actual to the IP call)
4977 -- before its definition.
4978
4979 declare
4980 Init_Call : constant Node_Id :=
4981 Remove_Init_Call (U_Ent, N);
4982
4983 begin
4984 if Present (Init_Call) then
4985 Append_Freeze_Action (U_Ent, Init_Call);
4986
4987 -- Reset Initialization_Statements pointer so that
4988 -- if there is a pragma Import further down, it can
4989 -- clear any default initialization.
4990
4991 Set_Initialization_Statements (U_Ent, Init_Call);
4992 end if;
4993 end;
4994
4995 -- Entity has delayed freeze, so we will generate an
4996 -- alignment check at the freeze point unless suppressed.
4997
4998 if not Range_Checks_Suppressed (U_Ent)
4999 and then not Alignment_Checks_Suppressed (U_Ent)
5000 then
5001 Set_Check_Address_Alignment (N);
5002 end if;
5003
5004 -- Kill the size check code, since we are not allocating
5005 -- the variable, it is somewhere else.
5006
5007 Kill_Size_Check_Code (U_Ent);
5008 end;
5009
5010 -- Not a valid entity for an address clause
5011
5012 else
5013 Error_Msg_N ("address cannot be given for &", Nam);
5014 end if;
5015 end Address;
5016
5017 ---------------
5018 -- Alignment --
5019 ---------------
5020
5021 -- Alignment attribute definition clause
5022
5023 when Attribute_Alignment => Alignment : declare
5024 Align : constant Uint := Get_Alignment_Value (Expr);
5025 Max_Align : constant Uint := UI_From_Int (Maximum_Alignment);
5026
5027 begin
5028 FOnly := True;
5029
5030 if not Is_Type (U_Ent)
5031 and then Ekind (U_Ent) /= E_Variable
5032 and then Ekind (U_Ent) /= E_Constant
5033 then
5034 Error_Msg_N ("alignment cannot be given for &", Nam);
5035
5036 elsif Duplicate_Clause then
5037 null;
5038
5039 elsif Align /= No_Uint then
5040 Set_Has_Alignment_Clause (U_Ent);
5041
5042 -- Tagged type case, check for attempt to set alignment to a
5043 -- value greater than Max_Align, and reset if so. This error
5044 -- is suppressed in ASIS mode to allow for different ASIS
5045 -- back ends or ASIS-based tools to query the illegal clause.
5046
5047 if Is_Tagged_Type (U_Ent)
5048 and then Align > Max_Align
5049 and then not ASIS_Mode
5050 then
5051 Error_Msg_N
5052 ("alignment for & set to Maximum_Aligment??", Nam);
5053 Set_Alignment (U_Ent, Max_Align);
5054
5055 -- All other cases
5056
5057 else
5058 Set_Alignment (U_Ent, Align);
5059 end if;
5060
5061 -- For an array type, U_Ent is the first subtype. In that case,
5062 -- also set the alignment of the anonymous base type so that
5063 -- other subtypes (such as the itypes for aggregates of the
5064 -- type) also receive the expected alignment.
5065
5066 if Is_Array_Type (U_Ent) then
5067 Set_Alignment (Base_Type (U_Ent), Align);
5068 end if;
5069 end if;
5070 end Alignment;
5071
5072 ---------------
5073 -- Bit_Order --
5074 ---------------
5075
5076 -- Bit_Order attribute definition clause
5077
5078 when Attribute_Bit_Order => Bit_Order : declare
5079 begin
5080 if not Is_Record_Type (U_Ent) then
5081 Error_Msg_N
5082 ("Bit_Order can only be defined for record type", Nam);
5083
5084 elsif Duplicate_Clause then
5085 null;
5086
5087 else
5088 Analyze_And_Resolve (Expr, RTE (RE_Bit_Order));
5089
5090 if Etype (Expr) = Any_Type then
5091 return;
5092
5093 elsif not Is_OK_Static_Expression (Expr) then
5094 Flag_Non_Static_Expr
5095 ("Bit_Order requires static expression!", Expr);
5096
5097 else
5098 if (Expr_Value (Expr) = 0) /= Bytes_Big_Endian then
5099 Set_Reverse_Bit_Order (Base_Type (U_Ent), True);
5100 end if;
5101 end if;
5102 end if;
5103 end Bit_Order;
5104
5105 --------------------
5106 -- Component_Size --
5107 --------------------
5108
5109 -- Component_Size attribute definition clause
5110
5111 when Attribute_Component_Size => Component_Size_Case : declare
5112 Csize : constant Uint := Static_Integer (Expr);
5113 Ctyp : Entity_Id;
5114 Btype : Entity_Id;
5115 Biased : Boolean;
5116 New_Ctyp : Entity_Id;
5117 Decl : Node_Id;
5118
5119 begin
5120 if not Is_Array_Type (U_Ent) then
5121 Error_Msg_N ("component size requires array type", Nam);
5122 return;
5123 end if;
5124
5125 Btype := Base_Type (U_Ent);
5126 Ctyp := Component_Type (Btype);
5127
5128 if Duplicate_Clause then
5129 null;
5130
5131 elsif Rep_Item_Too_Early (Btype, N) then
5132 null;
5133
5134 elsif Csize /= No_Uint then
5135 Check_Size (Expr, Ctyp, Csize, Biased);
5136
5137 -- For the biased case, build a declaration for a subtype that
5138 -- will be used to represent the biased subtype that reflects
5139 -- the biased representation of components. We need the subtype
5140 -- to get proper conversions on referencing elements of the
5141 -- array.
5142
5143 if Biased then
5144 New_Ctyp :=
5145 Make_Defining_Identifier (Loc,
5146 Chars =>
5147 New_External_Name (Chars (U_Ent), 'C', 0, 'T'));
5148
5149 Decl :=
5150 Make_Subtype_Declaration (Loc,
5151 Defining_Identifier => New_Ctyp,
5152 Subtype_Indication =>
5153 New_Occurrence_Of (Component_Type (Btype), Loc));
5154
5155 Set_Parent (Decl, N);
5156 Analyze (Decl, Suppress => All_Checks);
5157
5158 Set_Has_Delayed_Freeze (New_Ctyp, False);
5159 Set_Esize (New_Ctyp, Csize);
5160 Set_RM_Size (New_Ctyp, Csize);
5161 Init_Alignment (New_Ctyp);
5162 Set_Is_Itype (New_Ctyp, True);
5163 Set_Associated_Node_For_Itype (New_Ctyp, U_Ent);
5164
5165 Set_Component_Type (Btype, New_Ctyp);
5166 Set_Biased (New_Ctyp, N, "component size clause");
5167 end if;
5168
5169 Set_Component_Size (Btype, Csize);
5170
5171 -- Deal with warning on overridden size
5172
5173 if Warn_On_Overridden_Size
5174 and then Has_Size_Clause (Ctyp)
5175 and then RM_Size (Ctyp) /= Csize
5176 then
5177 Error_Msg_NE
5178 ("component size overrides size clause for&?S?", N, Ctyp);
5179 end if;
5180
5181 Set_Has_Component_Size_Clause (Btype, True);
5182 Set_Has_Non_Standard_Rep (Btype, True);
5183 end if;
5184 end Component_Size_Case;
5185
5186 -----------------------
5187 -- Constant_Indexing --
5188 -----------------------
5189
5190 when Attribute_Constant_Indexing =>
5191 Check_Indexing_Functions;
5192
5193 ---------
5194 -- CPU --
5195 ---------
5196
5197 when Attribute_CPU => CPU :
5198 begin
5199 -- CPU attribute definition clause not allowed except from aspect
5200 -- specification.
5201
5202 if From_Aspect_Specification (N) then
5203 if not Is_Task_Type (U_Ent) then
5204 Error_Msg_N ("CPU can only be defined for task", Nam);
5205
5206 elsif Duplicate_Clause then
5207 null;
5208
5209 else
5210 -- The expression must be analyzed in the special manner
5211 -- described in "Handling of Default and Per-Object
5212 -- Expressions" in sem.ads.
5213
5214 -- The visibility to the discriminants must be restored
5215
5216 Push_Scope_And_Install_Discriminants (U_Ent);
5217 Preanalyze_Spec_Expression (Expr, RTE (RE_CPU_Range));
5218 Uninstall_Discriminants_And_Pop_Scope (U_Ent);
5219
5220 if not Is_OK_Static_Expression (Expr) then
5221 Check_Restriction (Static_Priorities, Expr);
5222 end if;
5223 end if;
5224
5225 else
5226 Error_Msg_N
5227 ("attribute& cannot be set with definition clause", N);
5228 end if;
5229 end CPU;
5230
5231 ----------------------
5232 -- Default_Iterator --
5233 ----------------------
5234
5235 when Attribute_Default_Iterator => Default_Iterator : declare
5236 Func : Entity_Id;
5237 Typ : Entity_Id;
5238
5239 begin
5240 -- If target type is untagged, further checks are irrelevant
5241
5242 if not Is_Tagged_Type (U_Ent) then
5243 Error_Msg_N
5244 ("aspect Default_Iterator applies to tagged type", Nam);
5245 return;
5246 end if;
5247
5248 Check_Iterator_Functions;
5249
5250 Analyze (Expr);
5251
5252 if not Is_Entity_Name (Expr)
5253 or else Ekind (Entity (Expr)) /= E_Function
5254 then
5255 Error_Msg_N ("aspect Iterator must be a function", Expr);
5256 return;
5257 else
5258 Func := Entity (Expr);
5259 end if;
5260
5261 -- The type of the first parameter must be T, T'class, or a
5262 -- corresponding access type (5.5.1 (8/3). If function is
5263 -- parameterless label type accordingly.
5264
5265 if No (First_Formal (Func)) then
5266 Typ := Any_Type;
5267 else
5268 Typ := Etype (First_Formal (Func));
5269 end if;
5270
5271 if Typ = U_Ent
5272 or else Typ = Class_Wide_Type (U_Ent)
5273 or else (Is_Access_Type (Typ)
5274 and then Designated_Type (Typ) = U_Ent)
5275 or else (Is_Access_Type (Typ)
5276 and then Designated_Type (Typ) =
5277 Class_Wide_Type (U_Ent))
5278 then
5279 null;
5280
5281 else
5282 Error_Msg_NE
5283 ("Default Iterator must be a primitive of&", Func, U_Ent);
5284 end if;
5285 end Default_Iterator;
5286
5287 ------------------------
5288 -- Dispatching_Domain --
5289 ------------------------
5290
5291 when Attribute_Dispatching_Domain => Dispatching_Domain :
5292 begin
5293 -- Dispatching_Domain attribute definition clause not allowed
5294 -- except from aspect specification.
5295
5296 if From_Aspect_Specification (N) then
5297 if not Is_Task_Type (U_Ent) then
5298 Error_Msg_N
5299 ("Dispatching_Domain can only be defined for task", Nam);
5300
5301 elsif Duplicate_Clause then
5302 null;
5303
5304 else
5305 -- The expression must be analyzed in the special manner
5306 -- described in "Handling of Default and Per-Object
5307 -- Expressions" in sem.ads.
5308
5309 -- The visibility to the discriminants must be restored
5310
5311 Push_Scope_And_Install_Discriminants (U_Ent);
5312
5313 Preanalyze_Spec_Expression
5314 (Expr, RTE (RE_Dispatching_Domain));
5315
5316 Uninstall_Discriminants_And_Pop_Scope (U_Ent);
5317 end if;
5318
5319 else
5320 Error_Msg_N
5321 ("attribute& cannot be set with definition clause", N);
5322 end if;
5323 end Dispatching_Domain;
5324
5325 ------------------
5326 -- External_Tag --
5327 ------------------
5328
5329 when Attribute_External_Tag => External_Tag :
5330 begin
5331 if not Is_Tagged_Type (U_Ent) then
5332 Error_Msg_N ("should be a tagged type", Nam);
5333 end if;
5334
5335 if Duplicate_Clause then
5336 null;
5337
5338 else
5339 Analyze_And_Resolve (Expr, Standard_String);
5340
5341 if not Is_OK_Static_Expression (Expr) then
5342 Flag_Non_Static_Expr
5343 ("static string required for tag name!", Nam);
5344 end if;
5345
5346 if not Is_Library_Level_Entity (U_Ent) then
5347 Error_Msg_NE
5348 ("??non-unique external tag supplied for &", N, U_Ent);
5349 Error_Msg_N
5350 ("\??same external tag applies to all subprogram calls",
5351 N);
5352 Error_Msg_N
5353 ("\??corresponding internal tag cannot be obtained", N);
5354 end if;
5355 end if;
5356 end External_Tag;
5357
5358 --------------------------
5359 -- Implicit_Dereference --
5360 --------------------------
5361
5362 when Attribute_Implicit_Dereference =>
5363
5364 -- Legality checks already performed at the point of the type
5365 -- declaration, aspect is not delayed.
5366
5367 null;
5368
5369 -----------
5370 -- Input --
5371 -----------
5372
5373 when Attribute_Input =>
5374 Analyze_Stream_TSS_Definition (TSS_Stream_Input);
5375 Set_Has_Specified_Stream_Input (Ent);
5376
5377 ------------------------
5378 -- Interrupt_Priority --
5379 ------------------------
5380
5381 when Attribute_Interrupt_Priority => Interrupt_Priority :
5382 begin
5383 -- Interrupt_Priority attribute definition clause not allowed
5384 -- except from aspect specification.
5385
5386 if From_Aspect_Specification (N) then
5387 if not Is_Concurrent_Type (U_Ent) then
5388 Error_Msg_N
5389 ("Interrupt_Priority can only be defined for task and "
5390 & "protected object", Nam);
5391
5392 elsif Duplicate_Clause then
5393 null;
5394
5395 else
5396 -- The expression must be analyzed in the special manner
5397 -- described in "Handling of Default and Per-Object
5398 -- Expressions" in sem.ads.
5399
5400 -- The visibility to the discriminants must be restored
5401
5402 Push_Scope_And_Install_Discriminants (U_Ent);
5403
5404 Preanalyze_Spec_Expression
5405 (Expr, RTE (RE_Interrupt_Priority));
5406
5407 Uninstall_Discriminants_And_Pop_Scope (U_Ent);
5408
5409 -- Check the No_Task_At_Interrupt_Priority restriction
5410
5411 if Is_Task_Type (U_Ent) then
5412 Check_Restriction (No_Task_At_Interrupt_Priority, N);
5413 end if;
5414 end if;
5415
5416 else
5417 Error_Msg_N
5418 ("attribute& cannot be set with definition clause", N);
5419 end if;
5420 end Interrupt_Priority;
5421
5422 --------------
5423 -- Iterable --
5424 --------------
5425
5426 when Attribute_Iterable =>
5427 Analyze (Expr);
5428
5429 if Nkind (Expr) /= N_Aggregate then
5430 Error_Msg_N ("aspect Iterable must be an aggregate", Expr);
5431 end if;
5432
5433 declare
5434 Assoc : Node_Id;
5435
5436 begin
5437 Assoc := First (Component_Associations (Expr));
5438 while Present (Assoc) loop
5439 if not Is_Entity_Name (Expression (Assoc)) then
5440 Error_Msg_N ("value must be a function", Assoc);
5441 end if;
5442
5443 Next (Assoc);
5444 end loop;
5445 end;
5446
5447 ----------------------
5448 -- Iterator_Element --
5449 ----------------------
5450
5451 when Attribute_Iterator_Element =>
5452 Analyze (Expr);
5453
5454 if not Is_Entity_Name (Expr)
5455 or else not Is_Type (Entity (Expr))
5456 then
5457 Error_Msg_N ("aspect Iterator_Element must be a type", Expr);
5458 end if;
5459
5460 -------------------
5461 -- Machine_Radix --
5462 -------------------
5463
5464 -- Machine radix attribute definition clause
5465
5466 when Attribute_Machine_Radix => Machine_Radix : declare
5467 Radix : constant Uint := Static_Integer (Expr);
5468
5469 begin
5470 if not Is_Decimal_Fixed_Point_Type (U_Ent) then
5471 Error_Msg_N ("decimal fixed-point type expected for &", Nam);
5472
5473 elsif Duplicate_Clause then
5474 null;
5475
5476 elsif Radix /= No_Uint then
5477 Set_Has_Machine_Radix_Clause (U_Ent);
5478 Set_Has_Non_Standard_Rep (Base_Type (U_Ent));
5479
5480 if Radix = 2 then
5481 null;
5482
5483 elsif Radix = 10 then
5484 Set_Machine_Radix_10 (U_Ent);
5485
5486 -- The following error is suppressed in ASIS mode to allow for
5487 -- different ASIS back ends or ASIS-based tools to query the
5488 -- illegal clause.
5489
5490 elsif not ASIS_Mode then
5491 Error_Msg_N ("machine radix value must be 2 or 10", Expr);
5492 end if;
5493 end if;
5494 end Machine_Radix;
5495
5496 -----------------
5497 -- Object_Size --
5498 -----------------
5499
5500 -- Object_Size attribute definition clause
5501
5502 when Attribute_Object_Size => Object_Size : declare
5503 Size : constant Uint := Static_Integer (Expr);
5504
5505 Biased : Boolean;
5506 pragma Warnings (Off, Biased);
5507
5508 begin
5509 if not Is_Type (U_Ent) then
5510 Error_Msg_N ("Object_Size cannot be given for &", Nam);
5511
5512 elsif Duplicate_Clause then
5513 null;
5514
5515 else
5516 Check_Size (Expr, U_Ent, Size, Biased);
5517
5518 -- The following errors are suppressed in ASIS mode to allow
5519 -- for different ASIS back ends or ASIS-based tools to query
5520 -- the illegal clause.
5521
5522 if ASIS_Mode then
5523 null;
5524
5525 elsif Is_Scalar_Type (U_Ent) then
5526 if Size /= 8 and then Size /= 16 and then Size /= 32
5527 and then UI_Mod (Size, 64) /= 0
5528 then
5529 Error_Msg_N
5530 ("Object_Size must be 8, 16, 32, or multiple of 64",
5531 Expr);
5532 end if;
5533
5534 elsif Size mod 8 /= 0 then
5535 Error_Msg_N ("Object_Size must be a multiple of 8", Expr);
5536 end if;
5537
5538 Set_Esize (U_Ent, Size);
5539 Set_Has_Object_Size_Clause (U_Ent);
5540 Alignment_Check_For_Size_Change (U_Ent, Size);
5541 end if;
5542 end Object_Size;
5543
5544 ------------
5545 -- Output --
5546 ------------
5547
5548 when Attribute_Output =>
5549 Analyze_Stream_TSS_Definition (TSS_Stream_Output);
5550 Set_Has_Specified_Stream_Output (Ent);
5551
5552 --------------
5553 -- Priority --
5554 --------------
5555
5556 when Attribute_Priority => Priority :
5557 begin
5558 -- Priority attribute definition clause not allowed except from
5559 -- aspect specification.
5560
5561 if From_Aspect_Specification (N) then
5562 if not (Is_Concurrent_Type (U_Ent)
5563 or else Ekind (U_Ent) = E_Procedure)
5564 then
5565 Error_Msg_N
5566 ("Priority can only be defined for task and protected "
5567 & "object", Nam);
5568
5569 elsif Duplicate_Clause then
5570 null;
5571
5572 else
5573 -- The expression must be analyzed in the special manner
5574 -- described in "Handling of Default and Per-Object
5575 -- Expressions" in sem.ads.
5576
5577 -- The visibility to the discriminants must be restored
5578
5579 Push_Scope_And_Install_Discriminants (U_Ent);
5580 Preanalyze_Spec_Expression (Expr, Standard_Integer);
5581 Uninstall_Discriminants_And_Pop_Scope (U_Ent);
5582
5583 if not Is_OK_Static_Expression (Expr) then
5584 Check_Restriction (Static_Priorities, Expr);
5585 end if;
5586 end if;
5587
5588 else
5589 Error_Msg_N
5590 ("attribute& cannot be set with definition clause", N);
5591 end if;
5592 end Priority;
5593
5594 ----------
5595 -- Read --
5596 ----------
5597
5598 when Attribute_Read =>
5599 Analyze_Stream_TSS_Definition (TSS_Stream_Read);
5600 Set_Has_Specified_Stream_Read (Ent);
5601
5602 --------------------------
5603 -- Scalar_Storage_Order --
5604 --------------------------
5605
5606 -- Scalar_Storage_Order attribute definition clause
5607
5608 when Attribute_Scalar_Storage_Order => Scalar_Storage_Order : declare
5609 begin
5610 if not (Is_Record_Type (U_Ent) or else Is_Array_Type (U_Ent)) then
5611 Error_Msg_N
5612 ("Scalar_Storage_Order can only be defined for record or "
5613 & "array type", Nam);
5614
5615 elsif Duplicate_Clause then
5616 null;
5617
5618 else
5619 Analyze_And_Resolve (Expr, RTE (RE_Bit_Order));
5620
5621 if Etype (Expr) = Any_Type then
5622 return;
5623
5624 elsif not Is_OK_Static_Expression (Expr) then
5625 Flag_Non_Static_Expr
5626 ("Scalar_Storage_Order requires static expression!", Expr);
5627
5628 elsif (Expr_Value (Expr) = 0) /= Bytes_Big_Endian then
5629
5630 -- Here for the case of a non-default (i.e. non-confirming)
5631 -- Scalar_Storage_Order attribute definition.
5632
5633 if Support_Nondefault_SSO_On_Target then
5634 Set_Reverse_Storage_Order (Base_Type (U_Ent), True);
5635 else
5636 Error_Msg_N
5637 ("non-default Scalar_Storage_Order not supported on "
5638 & "target", Expr);
5639 end if;
5640 end if;
5641
5642 -- Clear SSO default indications since explicit setting of the
5643 -- order overrides the defaults.
5644
5645 Set_SSO_Set_Low_By_Default (Base_Type (U_Ent), False);
5646 Set_SSO_Set_High_By_Default (Base_Type (U_Ent), False);
5647 end if;
5648 end Scalar_Storage_Order;
5649
5650 ----------
5651 -- Size --
5652 ----------
5653
5654 -- Size attribute definition clause
5655
5656 when Attribute_Size => Size : declare
5657 Size : constant Uint := Static_Integer (Expr);
5658 Etyp : Entity_Id;
5659 Biased : Boolean;
5660
5661 begin
5662 FOnly := True;
5663
5664 if Duplicate_Clause then
5665 null;
5666
5667 elsif not Is_Type (U_Ent)
5668 and then Ekind (U_Ent) /= E_Variable
5669 and then Ekind (U_Ent) /= E_Constant
5670 then
5671 Error_Msg_N ("size cannot be given for &", Nam);
5672
5673 elsif Is_Array_Type (U_Ent)
5674 and then not Is_Constrained (U_Ent)
5675 then
5676 Error_Msg_N
5677 ("size cannot be given for unconstrained array", Nam);
5678
5679 elsif Size /= No_Uint then
5680 if Is_Type (U_Ent) then
5681 Etyp := U_Ent;
5682 else
5683 Etyp := Etype (U_Ent);
5684 end if;
5685
5686 -- Check size, note that Gigi is in charge of checking that the
5687 -- size of an array or record type is OK. Also we do not check
5688 -- the size in the ordinary fixed-point case, since it is too
5689 -- early to do so (there may be subsequent small clause that
5690 -- affects the size). We can check the size if a small clause
5691 -- has already been given.
5692
5693 if not Is_Ordinary_Fixed_Point_Type (U_Ent)
5694 or else Has_Small_Clause (U_Ent)
5695 then
5696 Check_Size (Expr, Etyp, Size, Biased);
5697 Set_Biased (U_Ent, N, "size clause", Biased);
5698 end if;
5699
5700 -- For types set RM_Size and Esize if possible
5701
5702 if Is_Type (U_Ent) then
5703 Set_RM_Size (U_Ent, Size);
5704
5705 -- For elementary types, increase Object_Size to power of 2,
5706 -- but not less than a storage unit in any case (normally
5707 -- this means it will be byte addressable).
5708
5709 -- For all other types, nothing else to do, we leave Esize
5710 -- (object size) unset, the back end will set it from the
5711 -- size and alignment in an appropriate manner.
5712
5713 -- In both cases, we check whether the alignment must be
5714 -- reset in the wake of the size change.
5715
5716 if Is_Elementary_Type (U_Ent) then
5717 if Size <= System_Storage_Unit then
5718 Init_Esize (U_Ent, System_Storage_Unit);
5719 elsif Size <= 16 then
5720 Init_Esize (U_Ent, 16);
5721 elsif Size <= 32 then
5722 Init_Esize (U_Ent, 32);
5723 else
5724 Set_Esize (U_Ent, (Size + 63) / 64 * 64);
5725 end if;
5726
5727 Alignment_Check_For_Size_Change (U_Ent, Esize (U_Ent));
5728 else
5729 Alignment_Check_For_Size_Change (U_Ent, Size);
5730 end if;
5731
5732 -- For objects, set Esize only
5733
5734 else
5735 -- The following error is suppressed in ASIS mode to allow
5736 -- for different ASIS back ends or ASIS-based tools to query
5737 -- the illegal clause.
5738
5739 if Is_Elementary_Type (Etyp)
5740 and then Size /= System_Storage_Unit
5741 and then Size /= System_Storage_Unit * 2
5742 and then Size /= System_Storage_Unit * 4
5743 and then Size /= System_Storage_Unit * 8
5744 and then not ASIS_Mode
5745 then
5746 Error_Msg_Uint_1 := UI_From_Int (System_Storage_Unit);
5747 Error_Msg_Uint_2 := Error_Msg_Uint_1 * 8;
5748 Error_Msg_N
5749 ("size for primitive object must be a power of 2 in "
5750 & "the range ^-^", N);
5751 end if;
5752
5753 Set_Esize (U_Ent, Size);
5754 end if;
5755
5756 Set_Has_Size_Clause (U_Ent);
5757 end if;
5758 end Size;
5759
5760 -----------
5761 -- Small --
5762 -----------
5763
5764 -- Small attribute definition clause
5765
5766 when Attribute_Small => Small : declare
5767 Implicit_Base : constant Entity_Id := Base_Type (U_Ent);
5768 Small : Ureal;
5769
5770 begin
5771 Analyze_And_Resolve (Expr, Any_Real);
5772
5773 if Etype (Expr) = Any_Type then
5774 return;
5775
5776 elsif not Is_OK_Static_Expression (Expr) then
5777 Flag_Non_Static_Expr
5778 ("small requires static expression!", Expr);
5779 return;
5780
5781 else
5782 Small := Expr_Value_R (Expr);
5783
5784 if Small <= Ureal_0 then
5785 Error_Msg_N ("small value must be greater than zero", Expr);
5786 return;
5787 end if;
5788
5789 end if;
5790
5791 if not Is_Ordinary_Fixed_Point_Type (U_Ent) then
5792 Error_Msg_N
5793 ("small requires an ordinary fixed point type", Nam);
5794
5795 elsif Has_Small_Clause (U_Ent) then
5796 Error_Msg_N ("small already given for &", Nam);
5797
5798 elsif Small > Delta_Value (U_Ent) then
5799 Error_Msg_N
5800 ("small value must not be greater than delta value", Nam);
5801
5802 else
5803 Set_Small_Value (U_Ent, Small);
5804 Set_Small_Value (Implicit_Base, Small);
5805 Set_Has_Small_Clause (U_Ent);
5806 Set_Has_Small_Clause (Implicit_Base);
5807 Set_Has_Non_Standard_Rep (Implicit_Base);
5808 end if;
5809 end Small;
5810
5811 ------------------
5812 -- Storage_Pool --
5813 ------------------
5814
5815 -- Storage_Pool attribute definition clause
5816
5817 when Attribute_Storage_Pool | Attribute_Simple_Storage_Pool => declare
5818 Pool : Entity_Id;
5819 T : Entity_Id;
5820
5821 begin
5822 if Ekind (U_Ent) = E_Access_Subprogram_Type then
5823 Error_Msg_N
5824 ("storage pool cannot be given for access-to-subprogram type",
5825 Nam);
5826 return;
5827
5828 elsif not
5829 Ekind_In (U_Ent, E_Access_Type, E_General_Access_Type)
5830 then
5831 Error_Msg_N
5832 ("storage pool can only be given for access types", Nam);
5833 return;
5834
5835 elsif Is_Derived_Type (U_Ent) then
5836 Error_Msg_N
5837 ("storage pool cannot be given for a derived access type",
5838 Nam);
5839
5840 elsif Duplicate_Clause then
5841 return;
5842
5843 elsif Present (Associated_Storage_Pool (U_Ent)) then
5844 Error_Msg_N ("storage pool already given for &", Nam);
5845 return;
5846 end if;
5847
5848 -- Check for Storage_Size previously given
5849
5850 declare
5851 SS : constant Node_Id :=
5852 Get_Attribute_Definition_Clause
5853 (U_Ent, Attribute_Storage_Size);
5854 begin
5855 if Present (SS) then
5856 Check_Pool_Size_Clash (U_Ent, N, SS);
5857 end if;
5858 end;
5859
5860 -- Storage_Pool case
5861
5862 if Id = Attribute_Storage_Pool then
5863 Analyze_And_Resolve
5864 (Expr, Class_Wide_Type (RTE (RE_Root_Storage_Pool)));
5865
5866 -- In the Simple_Storage_Pool case, we allow a variable of any
5867 -- simple storage pool type, so we Resolve without imposing an
5868 -- expected type.
5869
5870 else
5871 Analyze_And_Resolve (Expr);
5872
5873 if not Present (Get_Rep_Pragma
5874 (Etype (Expr), Name_Simple_Storage_Pool_Type))
5875 then
5876 Error_Msg_N
5877 ("expression must be of a simple storage pool type", Expr);
5878 end if;
5879 end if;
5880
5881 if not Denotes_Variable (Expr) then
5882 Error_Msg_N ("storage pool must be a variable", Expr);
5883 return;
5884 end if;
5885
5886 if Nkind (Expr) = N_Type_Conversion then
5887 T := Etype (Expression (Expr));
5888 else
5889 T := Etype (Expr);
5890 end if;
5891
5892 -- The Stack_Bounded_Pool is used internally for implementing
5893 -- access types with a Storage_Size. Since it only work properly
5894 -- when used on one specific type, we need to check that it is not
5895 -- hijacked improperly:
5896
5897 -- type T is access Integer;
5898 -- for T'Storage_Size use n;
5899 -- type Q is access Float;
5900 -- for Q'Storage_Size use T'Storage_Size; -- incorrect
5901
5902 if RTE_Available (RE_Stack_Bounded_Pool)
5903 and then Base_Type (T) = RTE (RE_Stack_Bounded_Pool)
5904 then
5905 Error_Msg_N ("non-shareable internal Pool", Expr);
5906 return;
5907 end if;
5908
5909 -- If the argument is a name that is not an entity name, then
5910 -- we construct a renaming operation to define an entity of
5911 -- type storage pool.
5912
5913 if not Is_Entity_Name (Expr)
5914 and then Is_Object_Reference (Expr)
5915 then
5916 Pool := Make_Temporary (Loc, 'P', Expr);
5917
5918 declare
5919 Rnode : constant Node_Id :=
5920 Make_Object_Renaming_Declaration (Loc,
5921 Defining_Identifier => Pool,
5922 Subtype_Mark =>
5923 New_Occurrence_Of (Etype (Expr), Loc),
5924 Name => Expr);
5925
5926 begin
5927 -- If the attribute definition clause comes from an aspect
5928 -- clause, then insert the renaming before the associated
5929 -- entity's declaration, since the attribute clause has
5930 -- not yet been appended to the declaration list.
5931
5932 if From_Aspect_Specification (N) then
5933 Insert_Before (Parent (Entity (N)), Rnode);
5934 else
5935 Insert_Before (N, Rnode);
5936 end if;
5937
5938 Analyze (Rnode);
5939 Set_Associated_Storage_Pool (U_Ent, Pool);
5940 end;
5941
5942 elsif Is_Entity_Name (Expr) then
5943 Pool := Entity (Expr);
5944
5945 -- If pool is a renamed object, get original one. This can
5946 -- happen with an explicit renaming, and within instances.
5947
5948 while Present (Renamed_Object (Pool))
5949 and then Is_Entity_Name (Renamed_Object (Pool))
5950 loop
5951 Pool := Entity (Renamed_Object (Pool));
5952 end loop;
5953
5954 if Present (Renamed_Object (Pool))
5955 and then Nkind (Renamed_Object (Pool)) = N_Type_Conversion
5956 and then Is_Entity_Name (Expression (Renamed_Object (Pool)))
5957 then
5958 Pool := Entity (Expression (Renamed_Object (Pool)));
5959 end if;
5960
5961 Set_Associated_Storage_Pool (U_Ent, Pool);
5962
5963 elsif Nkind (Expr) = N_Type_Conversion
5964 and then Is_Entity_Name (Expression (Expr))
5965 and then Nkind (Original_Node (Expr)) = N_Attribute_Reference
5966 then
5967 Pool := Entity (Expression (Expr));
5968 Set_Associated_Storage_Pool (U_Ent, Pool);
5969
5970 else
5971 Error_Msg_N ("incorrect reference to a Storage Pool", Expr);
5972 return;
5973 end if;
5974 end;
5975
5976 ------------------
5977 -- Storage_Size --
5978 ------------------
5979
5980 -- Storage_Size attribute definition clause
5981
5982 when Attribute_Storage_Size => Storage_Size : declare
5983 Btype : constant Entity_Id := Base_Type (U_Ent);
5984
5985 begin
5986 if Is_Task_Type (U_Ent) then
5987
5988 -- Check obsolescent (but never obsolescent if from aspect)
5989
5990 if not From_Aspect_Specification (N) then
5991 Check_Restriction (No_Obsolescent_Features, N);
5992
5993 if Warn_On_Obsolescent_Feature then
5994 Error_Msg_N
5995 ("?j?storage size clause for task is an obsolescent "
5996 & "feature (RM J.9)", N);
5997 Error_Msg_N ("\?j?use Storage_Size pragma instead", N);
5998 end if;
5999 end if;
6000
6001 FOnly := True;
6002 end if;
6003
6004 if not Is_Access_Type (U_Ent)
6005 and then Ekind (U_Ent) /= E_Task_Type
6006 then
6007 Error_Msg_N ("storage size cannot be given for &", Nam);
6008
6009 elsif Is_Access_Type (U_Ent) and Is_Derived_Type (U_Ent) then
6010 Error_Msg_N
6011 ("storage size cannot be given for a derived access type",
6012 Nam);
6013
6014 elsif Duplicate_Clause then
6015 null;
6016
6017 else
6018 Analyze_And_Resolve (Expr, Any_Integer);
6019
6020 if Is_Access_Type (U_Ent) then
6021
6022 -- Check for Storage_Pool previously given
6023
6024 declare
6025 SP : constant Node_Id :=
6026 Get_Attribute_Definition_Clause
6027 (U_Ent, Attribute_Storage_Pool);
6028
6029 begin
6030 if Present (SP) then
6031 Check_Pool_Size_Clash (U_Ent, SP, N);
6032 end if;
6033 end;
6034
6035 -- Special case of for x'Storage_Size use 0
6036
6037 if Is_OK_Static_Expression (Expr)
6038 and then Expr_Value (Expr) = 0
6039 then
6040 Set_No_Pool_Assigned (Btype);
6041 end if;
6042 end if;
6043
6044 Set_Has_Storage_Size_Clause (Btype);
6045 end if;
6046 end Storage_Size;
6047
6048 -----------------
6049 -- Stream_Size --
6050 -----------------
6051
6052 when Attribute_Stream_Size => Stream_Size : declare
6053 Size : constant Uint := Static_Integer (Expr);
6054
6055 begin
6056 if Ada_Version <= Ada_95 then
6057 Check_Restriction (No_Implementation_Attributes, N);
6058 end if;
6059
6060 if Duplicate_Clause then
6061 null;
6062
6063 elsif Is_Elementary_Type (U_Ent) then
6064
6065 -- The following errors are suppressed in ASIS mode to allow
6066 -- for different ASIS back ends or ASIS-based tools to query
6067 -- the illegal clause.
6068
6069 if ASIS_Mode then
6070 null;
6071
6072 elsif Size /= System_Storage_Unit
6073 and then Size /= System_Storage_Unit * 2
6074 and then Size /= System_Storage_Unit * 4
6075 and then Size /= System_Storage_Unit * 8
6076 then
6077 Error_Msg_Uint_1 := UI_From_Int (System_Storage_Unit);
6078 Error_Msg_N
6079 ("stream size for elementary type must be a power of 2 "
6080 & "and at least ^", N);
6081
6082 elsif RM_Size (U_Ent) > Size then
6083 Error_Msg_Uint_1 := RM_Size (U_Ent);
6084 Error_Msg_N
6085 ("stream size for elementary type must be a power of 2 "
6086 & "and at least ^", N);
6087 end if;
6088
6089 Set_Has_Stream_Size_Clause (U_Ent);
6090
6091 else
6092 Error_Msg_N ("Stream_Size cannot be given for &", Nam);
6093 end if;
6094 end Stream_Size;
6095
6096 ----------------
6097 -- Value_Size --
6098 ----------------
6099
6100 -- Value_Size attribute definition clause
6101
6102 when Attribute_Value_Size => Value_Size : declare
6103 Size : constant Uint := Static_Integer (Expr);
6104 Biased : Boolean;
6105
6106 begin
6107 if not Is_Type (U_Ent) then
6108 Error_Msg_N ("Value_Size cannot be given for &", Nam);
6109
6110 elsif Duplicate_Clause then
6111 null;
6112
6113 elsif Is_Array_Type (U_Ent)
6114 and then not Is_Constrained (U_Ent)
6115 then
6116 Error_Msg_N
6117 ("Value_Size cannot be given for unconstrained array", Nam);
6118
6119 else
6120 if Is_Elementary_Type (U_Ent) then
6121 Check_Size (Expr, U_Ent, Size, Biased);
6122 Set_Biased (U_Ent, N, "value size clause", Biased);
6123 end if;
6124
6125 Set_RM_Size (U_Ent, Size);
6126 end if;
6127 end Value_Size;
6128
6129 -----------------------
6130 -- Variable_Indexing --
6131 -----------------------
6132
6133 when Attribute_Variable_Indexing =>
6134 Check_Indexing_Functions;
6135
6136 -----------
6137 -- Write --
6138 -----------
6139
6140 when Attribute_Write =>
6141 Analyze_Stream_TSS_Definition (TSS_Stream_Write);
6142 Set_Has_Specified_Stream_Write (Ent);
6143
6144 -- All other attributes cannot be set
6145
6146 when others =>
6147 Error_Msg_N
6148 ("attribute& cannot be set with definition clause", N);
6149 end case;
6150
6151 -- The test for the type being frozen must be performed after any
6152 -- expression the clause has been analyzed since the expression itself
6153 -- might cause freezing that makes the clause illegal.
6154
6155 if Rep_Item_Too_Late (U_Ent, N, FOnly) then
6156 return;
6157 end if;
6158 end Analyze_Attribute_Definition_Clause;
6159
6160 ----------------------------
6161 -- Analyze_Code_Statement --
6162 ----------------------------
6163
6164 procedure Analyze_Code_Statement (N : Node_Id) is
6165 HSS : constant Node_Id := Parent (N);
6166 SBody : constant Node_Id := Parent (HSS);
6167 Subp : constant Entity_Id := Current_Scope;
6168 Stmt : Node_Id;
6169 Decl : Node_Id;
6170 StmtO : Node_Id;
6171 DeclO : Node_Id;
6172
6173 begin
6174 -- Accept foreign code statements for CodePeer. The analysis is skipped
6175 -- to avoid rejecting unrecognized constructs.
6176
6177 if CodePeer_Mode then
6178 Set_Analyzed (N);
6179 return;
6180 end if;
6181
6182 -- Analyze and check we get right type, note that this implements the
6183 -- requirement (RM 13.8(1)) that Machine_Code be with'ed, since that is
6184 -- the only way that Asm_Insn could possibly be visible.
6185
6186 Analyze_And_Resolve (Expression (N));
6187
6188 if Etype (Expression (N)) = Any_Type then
6189 return;
6190 elsif Etype (Expression (N)) /= RTE (RE_Asm_Insn) then
6191 Error_Msg_N ("incorrect type for code statement", N);
6192 return;
6193 end if;
6194
6195 Check_Code_Statement (N);
6196
6197 -- Make sure we appear in the handled statement sequence of a subprogram
6198 -- (RM 13.8(3)).
6199
6200 if Nkind (HSS) /= N_Handled_Sequence_Of_Statements
6201 or else Nkind (SBody) /= N_Subprogram_Body
6202 then
6203 Error_Msg_N
6204 ("code statement can only appear in body of subprogram", N);
6205 return;
6206 end if;
6207
6208 -- Do remaining checks (RM 13.8(3)) if not already done
6209
6210 if not Is_Machine_Code_Subprogram (Subp) then
6211 Set_Is_Machine_Code_Subprogram (Subp);
6212
6213 -- No exception handlers allowed
6214
6215 if Present (Exception_Handlers (HSS)) then
6216 Error_Msg_N
6217 ("exception handlers not permitted in machine code subprogram",
6218 First (Exception_Handlers (HSS)));
6219 end if;
6220
6221 -- No declarations other than use clauses and pragmas (we allow
6222 -- certain internally generated declarations as well).
6223
6224 Decl := First (Declarations (SBody));
6225 while Present (Decl) loop
6226 DeclO := Original_Node (Decl);
6227 if Comes_From_Source (DeclO)
6228 and not Nkind_In (DeclO, N_Pragma,
6229 N_Use_Package_Clause,
6230 N_Use_Type_Clause,
6231 N_Implicit_Label_Declaration)
6232 then
6233 Error_Msg_N
6234 ("this declaration not allowed in machine code subprogram",
6235 DeclO);
6236 end if;
6237
6238 Next (Decl);
6239 end loop;
6240
6241 -- No statements other than code statements, pragmas, and labels.
6242 -- Again we allow certain internally generated statements.
6243
6244 -- In Ada 2012, qualified expressions are names, and the code
6245 -- statement is initially parsed as a procedure call.
6246
6247 Stmt := First (Statements (HSS));
6248 while Present (Stmt) loop
6249 StmtO := Original_Node (Stmt);
6250
6251 -- A procedure call transformed into a code statement is OK
6252
6253 if Ada_Version >= Ada_2012
6254 and then Nkind (StmtO) = N_Procedure_Call_Statement
6255 and then Nkind (Name (StmtO)) = N_Qualified_Expression
6256 then
6257 null;
6258
6259 elsif Comes_From_Source (StmtO)
6260 and then not Nkind_In (StmtO, N_Pragma,
6261 N_Label,
6262 N_Code_Statement)
6263 then
6264 Error_Msg_N
6265 ("this statement is not allowed in machine code subprogram",
6266 StmtO);
6267 end if;
6268
6269 Next (Stmt);
6270 end loop;
6271 end if;
6272 end Analyze_Code_Statement;
6273
6274 -----------------------------------------------
6275 -- Analyze_Enumeration_Representation_Clause --
6276 -----------------------------------------------
6277
6278 procedure Analyze_Enumeration_Representation_Clause (N : Node_Id) is
6279 Ident : constant Node_Id := Identifier (N);
6280 Aggr : constant Node_Id := Array_Aggregate (N);
6281 Enumtype : Entity_Id;
6282 Elit : Entity_Id;
6283 Expr : Node_Id;
6284 Assoc : Node_Id;
6285 Choice : Node_Id;
6286 Val : Uint;
6287
6288 Err : Boolean := False;
6289 -- Set True to avoid cascade errors and crashes on incorrect source code
6290
6291 Lo : constant Uint := Expr_Value (Type_Low_Bound (Universal_Integer));
6292 Hi : constant Uint := Expr_Value (Type_High_Bound (Universal_Integer));
6293 -- Allowed range of universal integer (= allowed range of enum lit vals)
6294
6295 Min : Uint;
6296 Max : Uint;
6297 -- Minimum and maximum values of entries
6298
6299 Max_Node : Node_Id;
6300 -- Pointer to node for literal providing max value
6301
6302 begin
6303 if Ignore_Rep_Clauses then
6304 Kill_Rep_Clause (N);
6305 return;
6306 end if;
6307
6308 -- Ignore enumeration rep clauses by default in CodePeer mode,
6309 -- unless -gnatd.I is specified, as a work around for potential false
6310 -- positive messages.
6311
6312 if CodePeer_Mode and not Debug_Flag_Dot_II then
6313 return;
6314 end if;
6315
6316 -- First some basic error checks
6317
6318 Find_Type (Ident);
6319 Enumtype := Entity (Ident);
6320
6321 if Enumtype = Any_Type
6322 or else Rep_Item_Too_Early (Enumtype, N)
6323 then
6324 return;
6325 else
6326 Enumtype := Underlying_Type (Enumtype);
6327 end if;
6328
6329 if not Is_Enumeration_Type (Enumtype) then
6330 Error_Msg_NE
6331 ("enumeration type required, found}",
6332 Ident, First_Subtype (Enumtype));
6333 return;
6334 end if;
6335
6336 -- Ignore rep clause on generic actual type. This will already have
6337 -- been flagged on the template as an error, and this is the safest
6338 -- way to ensure we don't get a junk cascaded message in the instance.
6339
6340 if Is_Generic_Actual_Type (Enumtype) then
6341 return;
6342
6343 -- Type must be in current scope
6344
6345 elsif Scope (Enumtype) /= Current_Scope then
6346 Error_Msg_N ("type must be declared in this scope", Ident);
6347 return;
6348
6349 -- Type must be a first subtype
6350
6351 elsif not Is_First_Subtype (Enumtype) then
6352 Error_Msg_N ("cannot give enumeration rep clause for subtype", N);
6353 return;
6354
6355 -- Ignore duplicate rep clause
6356
6357 elsif Has_Enumeration_Rep_Clause (Enumtype) then
6358 Error_Msg_N ("duplicate enumeration rep clause ignored", N);
6359 return;
6360
6361 -- Don't allow rep clause for standard [wide_[wide_]]character
6362
6363 elsif Is_Standard_Character_Type (Enumtype) then
6364 Error_Msg_N ("enumeration rep clause not allowed for this type", N);
6365 return;
6366
6367 -- Check that the expression is a proper aggregate (no parentheses)
6368
6369 elsif Paren_Count (Aggr) /= 0 then
6370 Error_Msg
6371 ("extra parentheses surrounding aggregate not allowed",
6372 First_Sloc (Aggr));
6373 return;
6374
6375 -- All tests passed, so set rep clause in place
6376
6377 else
6378 Set_Has_Enumeration_Rep_Clause (Enumtype);
6379 Set_Has_Enumeration_Rep_Clause (Base_Type (Enumtype));
6380 end if;
6381
6382 -- Now we process the aggregate. Note that we don't use the normal
6383 -- aggregate code for this purpose, because we don't want any of the
6384 -- normal expansion activities, and a number of special semantic
6385 -- rules apply (including the component type being any integer type)
6386
6387 Elit := First_Literal (Enumtype);
6388
6389 -- First the positional entries if any
6390
6391 if Present (Expressions (Aggr)) then
6392 Expr := First (Expressions (Aggr));
6393 while Present (Expr) loop
6394 if No (Elit) then
6395 Error_Msg_N ("too many entries in aggregate", Expr);
6396 return;
6397 end if;
6398
6399 Val := Static_Integer (Expr);
6400
6401 -- Err signals that we found some incorrect entries processing
6402 -- the list. The final checks for completeness and ordering are
6403 -- skipped in this case.
6404
6405 if Val = No_Uint then
6406 Err := True;
6407
6408 elsif Val < Lo or else Hi < Val then
6409 Error_Msg_N ("value outside permitted range", Expr);
6410 Err := True;
6411 end if;
6412
6413 Set_Enumeration_Rep (Elit, Val);
6414 Set_Enumeration_Rep_Expr (Elit, Expr);
6415 Next (Expr);
6416 Next (Elit);
6417 end loop;
6418 end if;
6419
6420 -- Now process the named entries if present
6421
6422 if Present (Component_Associations (Aggr)) then
6423 Assoc := First (Component_Associations (Aggr));
6424 while Present (Assoc) loop
6425 Choice := First (Choices (Assoc));
6426
6427 if Present (Next (Choice)) then
6428 Error_Msg_N
6429 ("multiple choice not allowed here", Next (Choice));
6430 Err := True;
6431 end if;
6432
6433 if Nkind (Choice) = N_Others_Choice then
6434 Error_Msg_N ("others choice not allowed here", Choice);
6435 Err := True;
6436
6437 elsif Nkind (Choice) = N_Range then
6438
6439 -- ??? should allow zero/one element range here
6440
6441 Error_Msg_N ("range not allowed here", Choice);
6442 Err := True;
6443
6444 else
6445 Analyze_And_Resolve (Choice, Enumtype);
6446
6447 if Error_Posted (Choice) then
6448 Err := True;
6449 end if;
6450
6451 if not Err then
6452 if Is_Entity_Name (Choice)
6453 and then Is_Type (Entity (Choice))
6454 then
6455 Error_Msg_N ("subtype name not allowed here", Choice);
6456 Err := True;
6457
6458 -- ??? should allow static subtype with zero/one entry
6459
6460 elsif Etype (Choice) = Base_Type (Enumtype) then
6461 if not Is_OK_Static_Expression (Choice) then
6462 Flag_Non_Static_Expr
6463 ("non-static expression used for choice!", Choice);
6464 Err := True;
6465
6466 else
6467 Elit := Expr_Value_E (Choice);
6468
6469 if Present (Enumeration_Rep_Expr (Elit)) then
6470 Error_Msg_Sloc :=
6471 Sloc (Enumeration_Rep_Expr (Elit));
6472 Error_Msg_NE
6473 ("representation for& previously given#",
6474 Choice, Elit);
6475 Err := True;
6476 end if;
6477
6478 Set_Enumeration_Rep_Expr (Elit, Expression (Assoc));
6479
6480 Expr := Expression (Assoc);
6481 Val := Static_Integer (Expr);
6482
6483 if Val = No_Uint then
6484 Err := True;
6485
6486 elsif Val < Lo or else Hi < Val then
6487 Error_Msg_N ("value outside permitted range", Expr);
6488 Err := True;
6489 end if;
6490
6491 Set_Enumeration_Rep (Elit, Val);
6492 end if;
6493 end if;
6494 end if;
6495 end if;
6496
6497 Next (Assoc);
6498 end loop;
6499 end if;
6500
6501 -- Aggregate is fully processed. Now we check that a full set of
6502 -- representations was given, and that they are in range and in order.
6503 -- These checks are only done if no other errors occurred.
6504
6505 if not Err then
6506 Min := No_Uint;
6507 Max := No_Uint;
6508
6509 Elit := First_Literal (Enumtype);
6510 while Present (Elit) loop
6511 if No (Enumeration_Rep_Expr (Elit)) then
6512 Error_Msg_NE ("missing representation for&!", N, Elit);
6513
6514 else
6515 Val := Enumeration_Rep (Elit);
6516
6517 if Min = No_Uint then
6518 Min := Val;
6519 end if;
6520
6521 if Val /= No_Uint then
6522 if Max /= No_Uint and then Val <= Max then
6523 Error_Msg_NE
6524 ("enumeration value for& not ordered!",
6525 Enumeration_Rep_Expr (Elit), Elit);
6526 end if;
6527
6528 Max_Node := Enumeration_Rep_Expr (Elit);
6529 Max := Val;
6530 end if;
6531
6532 -- If there is at least one literal whose representation is not
6533 -- equal to the Pos value, then note that this enumeration type
6534 -- has a non-standard representation.
6535
6536 if Val /= Enumeration_Pos (Elit) then
6537 Set_Has_Non_Standard_Rep (Base_Type (Enumtype));
6538 end if;
6539 end if;
6540
6541 Next (Elit);
6542 end loop;
6543
6544 -- Now set proper size information
6545
6546 declare
6547 Minsize : Uint := UI_From_Int (Minimum_Size (Enumtype));
6548
6549 begin
6550 if Has_Size_Clause (Enumtype) then
6551
6552 -- All OK, if size is OK now
6553
6554 if RM_Size (Enumtype) >= Minsize then
6555 null;
6556
6557 else
6558 -- Try if we can get by with biasing
6559
6560 Minsize :=
6561 UI_From_Int (Minimum_Size (Enumtype, Biased => True));
6562
6563 -- Error message if even biasing does not work
6564
6565 if RM_Size (Enumtype) < Minsize then
6566 Error_Msg_Uint_1 := RM_Size (Enumtype);
6567 Error_Msg_Uint_2 := Max;
6568 Error_Msg_N
6569 ("previously given size (^) is too small "
6570 & "for this value (^)", Max_Node);
6571
6572 -- If biasing worked, indicate that we now have biased rep
6573
6574 else
6575 Set_Biased
6576 (Enumtype, Size_Clause (Enumtype), "size clause");
6577 end if;
6578 end if;
6579
6580 else
6581 Set_RM_Size (Enumtype, Minsize);
6582 Set_Enum_Esize (Enumtype);
6583 end if;
6584
6585 Set_RM_Size (Base_Type (Enumtype), RM_Size (Enumtype));
6586 Set_Esize (Base_Type (Enumtype), Esize (Enumtype));
6587 Set_Alignment (Base_Type (Enumtype), Alignment (Enumtype));
6588 end;
6589 end if;
6590
6591 -- We repeat the too late test in case it froze itself
6592
6593 if Rep_Item_Too_Late (Enumtype, N) then
6594 null;
6595 end if;
6596 end Analyze_Enumeration_Representation_Clause;
6597
6598 ----------------------------
6599 -- Analyze_Free_Statement --
6600 ----------------------------
6601
6602 procedure Analyze_Free_Statement (N : Node_Id) is
6603 begin
6604 Analyze (Expression (N));
6605 end Analyze_Free_Statement;
6606
6607 ---------------------------
6608 -- Analyze_Freeze_Entity --
6609 ---------------------------
6610
6611 procedure Analyze_Freeze_Entity (N : Node_Id) is
6612 begin
6613 Freeze_Entity_Checks (N);
6614 end Analyze_Freeze_Entity;
6615
6616 -----------------------------------
6617 -- Analyze_Freeze_Generic_Entity --
6618 -----------------------------------
6619
6620 procedure Analyze_Freeze_Generic_Entity (N : Node_Id) is
6621 begin
6622 Freeze_Entity_Checks (N);
6623 end Analyze_Freeze_Generic_Entity;
6624
6625 ------------------------------------------
6626 -- Analyze_Record_Representation_Clause --
6627 ------------------------------------------
6628
6629 -- Note: we check as much as we can here, but we can't do any checks
6630 -- based on the position values (e.g. overlap checks) until freeze time
6631 -- because especially in Ada 2005 (machine scalar mode), the processing
6632 -- for non-standard bit order can substantially change the positions.
6633 -- See procedure Check_Record_Representation_Clause (called from Freeze)
6634 -- for the remainder of this processing.
6635
6636 procedure Analyze_Record_Representation_Clause (N : Node_Id) is
6637 Ident : constant Node_Id := Identifier (N);
6638 Biased : Boolean;
6639 CC : Node_Id;
6640 Comp : Entity_Id;
6641 Fbit : Uint;
6642 Hbit : Uint := Uint_0;
6643 Lbit : Uint;
6644 Ocomp : Entity_Id;
6645 Posit : Uint;
6646 Rectype : Entity_Id;
6647 Recdef : Node_Id;
6648
6649 function Is_Inherited (Comp : Entity_Id) return Boolean;
6650 -- True if Comp is an inherited component in a record extension
6651
6652 ------------------
6653 -- Is_Inherited --
6654 ------------------
6655
6656 function Is_Inherited (Comp : Entity_Id) return Boolean is
6657 Comp_Base : Entity_Id;
6658
6659 begin
6660 if Ekind (Rectype) = E_Record_Subtype then
6661 Comp_Base := Original_Record_Component (Comp);
6662 else
6663 Comp_Base := Comp;
6664 end if;
6665
6666 return Comp_Base /= Original_Record_Component (Comp_Base);
6667 end Is_Inherited;
6668
6669 -- Local variables
6670
6671 Is_Record_Extension : Boolean;
6672 -- True if Rectype is a record extension
6673
6674 CR_Pragma : Node_Id := Empty;
6675 -- Points to N_Pragma node if Complete_Representation pragma present
6676
6677 -- Start of processing for Analyze_Record_Representation_Clause
6678
6679 begin
6680 if Ignore_Rep_Clauses then
6681 Kill_Rep_Clause (N);
6682 return;
6683 end if;
6684
6685 Find_Type (Ident);
6686 Rectype := Entity (Ident);
6687
6688 if Rectype = Any_Type or else Rep_Item_Too_Early (Rectype, N) then
6689 return;
6690 else
6691 Rectype := Underlying_Type (Rectype);
6692 end if;
6693
6694 -- First some basic error checks
6695
6696 if not Is_Record_Type (Rectype) then
6697 Error_Msg_NE
6698 ("record type required, found}", Ident, First_Subtype (Rectype));
6699 return;
6700
6701 elsif Scope (Rectype) /= Current_Scope then
6702 Error_Msg_N ("type must be declared in this scope", N);
6703 return;
6704
6705 elsif not Is_First_Subtype (Rectype) then
6706 Error_Msg_N ("cannot give record rep clause for subtype", N);
6707 return;
6708
6709 elsif Has_Record_Rep_Clause (Rectype) then
6710 Error_Msg_N ("duplicate record rep clause ignored", N);
6711 return;
6712
6713 elsif Rep_Item_Too_Late (Rectype, N) then
6714 return;
6715 end if;
6716
6717 -- We know we have a first subtype, now possibly go to the anonymous
6718 -- base type to determine whether Rectype is a record extension.
6719
6720 Recdef := Type_Definition (Declaration_Node (Base_Type (Rectype)));
6721 Is_Record_Extension :=
6722 Nkind (Recdef) = N_Derived_Type_Definition
6723 and then Present (Record_Extension_Part (Recdef));
6724
6725 if Present (Mod_Clause (N)) then
6726 declare
6727 Loc : constant Source_Ptr := Sloc (N);
6728 M : constant Node_Id := Mod_Clause (N);
6729 P : constant List_Id := Pragmas_Before (M);
6730 AtM_Nod : Node_Id;
6731
6732 Mod_Val : Uint;
6733 pragma Warnings (Off, Mod_Val);
6734
6735 begin
6736 Check_Restriction (No_Obsolescent_Features, Mod_Clause (N));
6737
6738 if Warn_On_Obsolescent_Feature then
6739 Error_Msg_N
6740 ("?j?mod clause is an obsolescent feature (RM J.8)", N);
6741 Error_Msg_N
6742 ("\?j?use alignment attribute definition clause instead", N);
6743 end if;
6744
6745 if Present (P) then
6746 Analyze_List (P);
6747 end if;
6748
6749 -- In ASIS_Mode mode, expansion is disabled, but we must convert
6750 -- the Mod clause into an alignment clause anyway, so that the
6751 -- back end can compute and back-annotate properly the size and
6752 -- alignment of types that may include this record.
6753
6754 -- This seems dubious, this destroys the source tree in a manner
6755 -- not detectable by ASIS ???
6756
6757 if Operating_Mode = Check_Semantics and then ASIS_Mode then
6758 AtM_Nod :=
6759 Make_Attribute_Definition_Clause (Loc,
6760 Name => New_Occurrence_Of (Base_Type (Rectype), Loc),
6761 Chars => Name_Alignment,
6762 Expression => Relocate_Node (Expression (M)));
6763
6764 Set_From_At_Mod (AtM_Nod);
6765 Insert_After (N, AtM_Nod);
6766 Mod_Val := Get_Alignment_Value (Expression (AtM_Nod));
6767 Set_Mod_Clause (N, Empty);
6768
6769 else
6770 -- Get the alignment value to perform error checking
6771
6772 Mod_Val := Get_Alignment_Value (Expression (M));
6773 end if;
6774 end;
6775 end if;
6776
6777 -- For untagged types, clear any existing component clauses for the
6778 -- type. If the type is derived, this is what allows us to override
6779 -- a rep clause for the parent. For type extensions, the representation
6780 -- of the inherited components is inherited, so we want to keep previous
6781 -- component clauses for completeness.
6782
6783 if not Is_Tagged_Type (Rectype) then
6784 Comp := First_Component_Or_Discriminant (Rectype);
6785 while Present (Comp) loop
6786 Set_Component_Clause (Comp, Empty);
6787 Next_Component_Or_Discriminant (Comp);
6788 end loop;
6789 end if;
6790
6791 -- All done if no component clauses
6792
6793 CC := First (Component_Clauses (N));
6794
6795 if No (CC) then
6796 return;
6797 end if;
6798
6799 -- A representation like this applies to the base type
6800
6801 Set_Has_Record_Rep_Clause (Base_Type (Rectype));
6802 Set_Has_Non_Standard_Rep (Base_Type (Rectype));
6803 Set_Has_Specified_Layout (Base_Type (Rectype));
6804
6805 -- Process the component clauses
6806
6807 while Present (CC) loop
6808
6809 -- Pragma
6810
6811 if Nkind (CC) = N_Pragma then
6812 Analyze (CC);
6813
6814 -- The only pragma of interest is Complete_Representation
6815
6816 if Pragma_Name (CC) = Name_Complete_Representation then
6817 CR_Pragma := CC;
6818 end if;
6819
6820 -- Processing for real component clause
6821
6822 else
6823 Posit := Static_Integer (Position (CC));
6824 Fbit := Static_Integer (First_Bit (CC));
6825 Lbit := Static_Integer (Last_Bit (CC));
6826
6827 if Posit /= No_Uint
6828 and then Fbit /= No_Uint
6829 and then Lbit /= No_Uint
6830 then
6831 if Posit < 0 then
6832 Error_Msg_N ("position cannot be negative", Position (CC));
6833
6834 elsif Fbit < 0 then
6835 Error_Msg_N ("first bit cannot be negative", First_Bit (CC));
6836
6837 -- The Last_Bit specified in a component clause must not be
6838 -- less than the First_Bit minus one (RM-13.5.1(10)).
6839
6840 elsif Lbit < Fbit - 1 then
6841 Error_Msg_N
6842 ("last bit cannot be less than first bit minus one",
6843 Last_Bit (CC));
6844
6845 -- Values look OK, so find the corresponding record component
6846 -- Even though the syntax allows an attribute reference for
6847 -- implementation-defined components, GNAT does not allow the
6848 -- tag to get an explicit position.
6849
6850 elsif Nkind (Component_Name (CC)) = N_Attribute_Reference then
6851 if Attribute_Name (Component_Name (CC)) = Name_Tag then
6852 Error_Msg_N ("position of tag cannot be specified", CC);
6853 else
6854 Error_Msg_N ("illegal component name", CC);
6855 end if;
6856
6857 else
6858 Comp := First_Entity (Rectype);
6859 while Present (Comp) loop
6860 exit when Chars (Comp) = Chars (Component_Name (CC));
6861 Next_Entity (Comp);
6862 end loop;
6863
6864 if No (Comp) then
6865
6866 -- Maybe component of base type that is absent from
6867 -- statically constrained first subtype.
6868
6869 Comp := First_Entity (Base_Type (Rectype));
6870 while Present (Comp) loop
6871 exit when Chars (Comp) = Chars (Component_Name (CC));
6872 Next_Entity (Comp);
6873 end loop;
6874 end if;
6875
6876 if No (Comp) then
6877 Error_Msg_N
6878 ("component clause is for non-existent field", CC);
6879
6880 -- Ada 2012 (AI05-0026): Any name that denotes a
6881 -- discriminant of an object of an unchecked union type
6882 -- shall not occur within a record_representation_clause.
6883
6884 -- The general restriction of using record rep clauses on
6885 -- Unchecked_Union types has now been lifted. Since it is
6886 -- possible to introduce a record rep clause which mentions
6887 -- the discriminant of an Unchecked_Union in non-Ada 2012
6888 -- code, this check is applied to all versions of the
6889 -- language.
6890
6891 elsif Ekind (Comp) = E_Discriminant
6892 and then Is_Unchecked_Union (Rectype)
6893 then
6894 Error_Msg_N
6895 ("cannot reference discriminant of unchecked union",
6896 Component_Name (CC));
6897
6898 elsif Is_Record_Extension and then Is_Inherited (Comp) then
6899 Error_Msg_NE
6900 ("component clause not allowed for inherited "
6901 & "component&", CC, Comp);
6902
6903 elsif Present (Component_Clause (Comp)) then
6904
6905 -- Diagnose duplicate rep clause, or check consistency
6906 -- if this is an inherited component. In a double fault,
6907 -- there may be a duplicate inconsistent clause for an
6908 -- inherited component.
6909
6910 if Scope (Original_Record_Component (Comp)) = Rectype
6911 or else Parent (Component_Clause (Comp)) = N
6912 then
6913 Error_Msg_Sloc := Sloc (Component_Clause (Comp));
6914 Error_Msg_N ("component clause previously given#", CC);
6915
6916 else
6917 declare
6918 Rep1 : constant Node_Id := Component_Clause (Comp);
6919 begin
6920 if Intval (Position (Rep1)) /=
6921 Intval (Position (CC))
6922 or else Intval (First_Bit (Rep1)) /=
6923 Intval (First_Bit (CC))
6924 or else Intval (Last_Bit (Rep1)) /=
6925 Intval (Last_Bit (CC))
6926 then
6927 Error_Msg_N
6928 ("component clause inconsistent with "
6929 & "representation of ancestor", CC);
6930
6931 elsif Warn_On_Redundant_Constructs then
6932 Error_Msg_N
6933 ("?r?redundant confirming component clause "
6934 & "for component!", CC);
6935 end if;
6936 end;
6937 end if;
6938
6939 -- Normal case where this is the first component clause we
6940 -- have seen for this entity, so set it up properly.
6941
6942 else
6943 -- Make reference for field in record rep clause and set
6944 -- appropriate entity field in the field identifier.
6945
6946 Generate_Reference
6947 (Comp, Component_Name (CC), Set_Ref => False);
6948 Set_Entity (Component_Name (CC), Comp);
6949
6950 -- Update Fbit and Lbit to the actual bit number
6951
6952 Fbit := Fbit + UI_From_Int (SSU) * Posit;
6953 Lbit := Lbit + UI_From_Int (SSU) * Posit;
6954
6955 if Has_Size_Clause (Rectype)
6956 and then RM_Size (Rectype) <= Lbit
6957 then
6958 Error_Msg_N
6959 ("bit number out of range of specified size",
6960 Last_Bit (CC));
6961 else
6962 Set_Component_Clause (Comp, CC);
6963 Set_Component_Bit_Offset (Comp, Fbit);
6964 Set_Esize (Comp, 1 + (Lbit - Fbit));
6965 Set_Normalized_First_Bit (Comp, Fbit mod SSU);
6966 Set_Normalized_Position (Comp, Fbit / SSU);
6967
6968 if Warn_On_Overridden_Size
6969 and then Has_Size_Clause (Etype (Comp))
6970 and then RM_Size (Etype (Comp)) /= Esize (Comp)
6971 then
6972 Error_Msg_NE
6973 ("?S?component size overrides size clause for&",
6974 Component_Name (CC), Etype (Comp));
6975 end if;
6976
6977 -- This information is also set in the corresponding
6978 -- component of the base type, found by accessing the
6979 -- Original_Record_Component link if it is present.
6980
6981 Ocomp := Original_Record_Component (Comp);
6982
6983 if Hbit < Lbit then
6984 Hbit := Lbit;
6985 end if;
6986
6987 Check_Size
6988 (Component_Name (CC),
6989 Etype (Comp),
6990 Esize (Comp),
6991 Biased);
6992
6993 Set_Biased
6994 (Comp, First_Node (CC), "component clause", Biased);
6995
6996 if Present (Ocomp) then
6997 Set_Component_Clause (Ocomp, CC);
6998 Set_Component_Bit_Offset (Ocomp, Fbit);
6999 Set_Normalized_First_Bit (Ocomp, Fbit mod SSU);
7000 Set_Normalized_Position (Ocomp, Fbit / SSU);
7001 Set_Esize (Ocomp, 1 + (Lbit - Fbit));
7002
7003 Set_Normalized_Position_Max
7004 (Ocomp, Normalized_Position (Ocomp));
7005
7006 -- Note: we don't use Set_Biased here, because we
7007 -- already gave a warning above if needed, and we
7008 -- would get a duplicate for the same name here.
7009
7010 Set_Has_Biased_Representation
7011 (Ocomp, Has_Biased_Representation (Comp));
7012 end if;
7013
7014 if Esize (Comp) < 0 then
7015 Error_Msg_N ("component size is negative", CC);
7016 end if;
7017 end if;
7018 end if;
7019 end if;
7020 end if;
7021 end if;
7022
7023 Next (CC);
7024 end loop;
7025
7026 -- Check missing components if Complete_Representation pragma appeared
7027
7028 if Present (CR_Pragma) then
7029 Comp := First_Component_Or_Discriminant (Rectype);
7030 while Present (Comp) loop
7031 if No (Component_Clause (Comp)) then
7032 Error_Msg_NE
7033 ("missing component clause for &", CR_Pragma, Comp);
7034 end if;
7035
7036 Next_Component_Or_Discriminant (Comp);
7037 end loop;
7038
7039 -- Give missing components warning if required
7040
7041 elsif Warn_On_Unrepped_Components then
7042 declare
7043 Num_Repped_Components : Nat := 0;
7044 Num_Unrepped_Components : Nat := 0;
7045
7046 begin
7047 -- First count number of repped and unrepped components
7048
7049 Comp := First_Component_Or_Discriminant (Rectype);
7050 while Present (Comp) loop
7051 if Present (Component_Clause (Comp)) then
7052 Num_Repped_Components := Num_Repped_Components + 1;
7053 else
7054 Num_Unrepped_Components := Num_Unrepped_Components + 1;
7055 end if;
7056
7057 Next_Component_Or_Discriminant (Comp);
7058 end loop;
7059
7060 -- We are only interested in the case where there is at least one
7061 -- unrepped component, and at least half the components have rep
7062 -- clauses. We figure that if less than half have them, then the
7063 -- partial rep clause is really intentional. If the component
7064 -- type has no underlying type set at this point (as for a generic
7065 -- formal type), we don't know enough to give a warning on the
7066 -- component.
7067
7068 if Num_Unrepped_Components > 0
7069 and then Num_Unrepped_Components < Num_Repped_Components
7070 then
7071 Comp := First_Component_Or_Discriminant (Rectype);
7072 while Present (Comp) loop
7073 if No (Component_Clause (Comp))
7074 and then Comes_From_Source (Comp)
7075 and then Present (Underlying_Type (Etype (Comp)))
7076 and then (Is_Scalar_Type (Underlying_Type (Etype (Comp)))
7077 or else Size_Known_At_Compile_Time
7078 (Underlying_Type (Etype (Comp))))
7079 and then not Has_Warnings_Off (Rectype)
7080
7081 -- Ignore discriminant in unchecked union, since it is
7082 -- not there, and cannot have a component clause.
7083
7084 and then (not Is_Unchecked_Union (Rectype)
7085 or else Ekind (Comp) /= E_Discriminant)
7086 then
7087 Error_Msg_Sloc := Sloc (Comp);
7088 Error_Msg_NE
7089 ("?C?no component clause given for & declared #",
7090 N, Comp);
7091 end if;
7092
7093 Next_Component_Or_Discriminant (Comp);
7094 end loop;
7095 end if;
7096 end;
7097 end if;
7098 end Analyze_Record_Representation_Clause;
7099
7100 -------------------------------------
7101 -- Build_Discrete_Static_Predicate --
7102 -------------------------------------
7103
7104 procedure Build_Discrete_Static_Predicate
7105 (Typ : Entity_Id;
7106 Expr : Node_Id;
7107 Nam : Name_Id)
7108 is
7109 Loc : constant Source_Ptr := Sloc (Expr);
7110
7111 Non_Static : exception;
7112 -- Raised if something non-static is found
7113
7114 Btyp : constant Entity_Id := Base_Type (Typ);
7115
7116 BLo : constant Uint := Expr_Value (Type_Low_Bound (Btyp));
7117 BHi : constant Uint := Expr_Value (Type_High_Bound (Btyp));
7118 -- Low bound and high bound value of base type of Typ
7119
7120 TLo : Uint;
7121 THi : Uint;
7122 -- Bounds for constructing the static predicate. We use the bound of the
7123 -- subtype if it is static, otherwise the corresponding base type bound.
7124 -- Note: a non-static subtype can have a static predicate.
7125
7126 type REnt is record
7127 Lo, Hi : Uint;
7128 end record;
7129 -- One entry in a Rlist value, a single REnt (range entry) value denotes
7130 -- one range from Lo to Hi. To represent a single value range Lo = Hi =
7131 -- value.
7132
7133 type RList is array (Nat range <>) of REnt;
7134 -- A list of ranges. The ranges are sorted in increasing order, and are
7135 -- disjoint (there is a gap of at least one value between each range in
7136 -- the table). A value is in the set of ranges in Rlist if it lies
7137 -- within one of these ranges.
7138
7139 False_Range : constant RList :=
7140 RList'(1 .. 0 => REnt'(No_Uint, No_Uint));
7141 -- An empty set of ranges represents a range list that can never be
7142 -- satisfied, since there are no ranges in which the value could lie,
7143 -- so it does not lie in any of them. False_Range is a canonical value
7144 -- for this empty set, but general processing should test for an Rlist
7145 -- with length zero (see Is_False predicate), since other null ranges
7146 -- may appear which must be treated as False.
7147
7148 True_Range : constant RList := RList'(1 => REnt'(BLo, BHi));
7149 -- Range representing True, value must be in the base range
7150
7151 function "and" (Left : RList; Right : RList) return RList;
7152 -- And's together two range lists, returning a range list. This is a set
7153 -- intersection operation.
7154
7155 function "or" (Left : RList; Right : RList) return RList;
7156 -- Or's together two range lists, returning a range list. This is a set
7157 -- union operation.
7158
7159 function "not" (Right : RList) return RList;
7160 -- Returns complement of a given range list, i.e. a range list
7161 -- representing all the values in TLo .. THi that are not in the input
7162 -- operand Right.
7163
7164 function Build_Val (V : Uint) return Node_Id;
7165 -- Return an analyzed N_Identifier node referencing this value, suitable
7166 -- for use as an entry in the Static_Discrte_Predicate list. This node
7167 -- is typed with the base type.
7168
7169 function Build_Range (Lo : Uint; Hi : Uint) return Node_Id;
7170 -- Return an analyzed N_Range node referencing this range, suitable for
7171 -- use as an entry in the Static_Discrete_Predicate list. This node is
7172 -- typed with the base type.
7173
7174 function Get_RList (Exp : Node_Id) return RList;
7175 -- This is a recursive routine that converts the given expression into a
7176 -- list of ranges, suitable for use in building the static predicate.
7177
7178 function Is_False (R : RList) return Boolean;
7179 pragma Inline (Is_False);
7180 -- Returns True if the given range list is empty, and thus represents a
7181 -- False list of ranges that can never be satisfied.
7182
7183 function Is_True (R : RList) return Boolean;
7184 -- Returns True if R trivially represents the True predicate by having a
7185 -- single range from BLo to BHi.
7186
7187 function Is_Type_Ref (N : Node_Id) return Boolean;
7188 pragma Inline (Is_Type_Ref);
7189 -- Returns if True if N is a reference to the type for the predicate in
7190 -- the expression (i.e. if it is an identifier whose Chars field matches
7191 -- the Nam given in the call). N must not be parenthesized, if the type
7192 -- name appears in parens, this routine will return False.
7193
7194 function Lo_Val (N : Node_Id) return Uint;
7195 -- Given an entry from a Static_Discrete_Predicate list that is either
7196 -- a static expression or static range, gets either the expression value
7197 -- or the low bound of the range.
7198
7199 function Hi_Val (N : Node_Id) return Uint;
7200 -- Given an entry from a Static_Discrete_Predicate list that is either
7201 -- a static expression or static range, gets either the expression value
7202 -- or the high bound of the range.
7203
7204 function Membership_Entry (N : Node_Id) return RList;
7205 -- Given a single membership entry (range, value, or subtype), returns
7206 -- the corresponding range list. Raises Static_Error if not static.
7207
7208 function Membership_Entries (N : Node_Id) return RList;
7209 -- Given an element on an alternatives list of a membership operation,
7210 -- returns the range list corresponding to this entry and all following
7211 -- entries (i.e. returns the "or" of this list of values).
7212
7213 function Stat_Pred (Typ : Entity_Id) return RList;
7214 -- Given a type, if it has a static predicate, then return the predicate
7215 -- as a range list, otherwise raise Non_Static.
7216
7217 -----------
7218 -- "and" --
7219 -----------
7220
7221 function "and" (Left : RList; Right : RList) return RList is
7222 FEnt : REnt;
7223 -- First range of result
7224
7225 SLeft : Nat := Left'First;
7226 -- Start of rest of left entries
7227
7228 SRight : Nat := Right'First;
7229 -- Start of rest of right entries
7230
7231 begin
7232 -- If either range is True, return the other
7233
7234 if Is_True (Left) then
7235 return Right;
7236 elsif Is_True (Right) then
7237 return Left;
7238 end if;
7239
7240 -- If either range is False, return False
7241
7242 if Is_False (Left) or else Is_False (Right) then
7243 return False_Range;
7244 end if;
7245
7246 -- Loop to remove entries at start that are disjoint, and thus just
7247 -- get discarded from the result entirely.
7248
7249 loop
7250 -- If no operands left in either operand, result is false
7251
7252 if SLeft > Left'Last or else SRight > Right'Last then
7253 return False_Range;
7254
7255 -- Discard first left operand entry if disjoint with right
7256
7257 elsif Left (SLeft).Hi < Right (SRight).Lo then
7258 SLeft := SLeft + 1;
7259
7260 -- Discard first right operand entry if disjoint with left
7261
7262 elsif Right (SRight).Hi < Left (SLeft).Lo then
7263 SRight := SRight + 1;
7264
7265 -- Otherwise we have an overlapping entry
7266
7267 else
7268 exit;
7269 end if;
7270 end loop;
7271
7272 -- Now we have two non-null operands, and first entries overlap. The
7273 -- first entry in the result will be the overlapping part of these
7274 -- two entries.
7275
7276 FEnt := REnt'(Lo => UI_Max (Left (SLeft).Lo, Right (SRight).Lo),
7277 Hi => UI_Min (Left (SLeft).Hi, Right (SRight).Hi));
7278
7279 -- Now we can remove the entry that ended at a lower value, since its
7280 -- contribution is entirely contained in Fent.
7281
7282 if Left (SLeft).Hi <= Right (SRight).Hi then
7283 SLeft := SLeft + 1;
7284 else
7285 SRight := SRight + 1;
7286 end if;
7287
7288 -- Compute result by concatenating this first entry with the "and" of
7289 -- the remaining parts of the left and right operands. Note that if
7290 -- either of these is empty, "and" will yield empty, so that we will
7291 -- end up with just Fent, which is what we want in that case.
7292
7293 return
7294 FEnt & (Left (SLeft .. Left'Last) and Right (SRight .. Right'Last));
7295 end "and";
7296
7297 -----------
7298 -- "not" --
7299 -----------
7300
7301 function "not" (Right : RList) return RList is
7302 begin
7303 -- Return True if False range
7304
7305 if Is_False (Right) then
7306 return True_Range;
7307 end if;
7308
7309 -- Return False if True range
7310
7311 if Is_True (Right) then
7312 return False_Range;
7313 end if;
7314
7315 -- Here if not trivial case
7316
7317 declare
7318 Result : RList (1 .. Right'Length + 1);
7319 -- May need one more entry for gap at beginning and end
7320
7321 Count : Nat := 0;
7322 -- Number of entries stored in Result
7323
7324 begin
7325 -- Gap at start
7326
7327 if Right (Right'First).Lo > TLo then
7328 Count := Count + 1;
7329 Result (Count) := REnt'(TLo, Right (Right'First).Lo - 1);
7330 end if;
7331
7332 -- Gaps between ranges
7333
7334 for J in Right'First .. Right'Last - 1 loop
7335 Count := Count + 1;
7336 Result (Count) := REnt'(Right (J).Hi + 1, Right (J + 1).Lo - 1);
7337 end loop;
7338
7339 -- Gap at end
7340
7341 if Right (Right'Last).Hi < THi then
7342 Count := Count + 1;
7343 Result (Count) := REnt'(Right (Right'Last).Hi + 1, THi);
7344 end if;
7345
7346 return Result (1 .. Count);
7347 end;
7348 end "not";
7349
7350 ----------
7351 -- "or" --
7352 ----------
7353
7354 function "or" (Left : RList; Right : RList) return RList is
7355 FEnt : REnt;
7356 -- First range of result
7357
7358 SLeft : Nat := Left'First;
7359 -- Start of rest of left entries
7360
7361 SRight : Nat := Right'First;
7362 -- Start of rest of right entries
7363
7364 begin
7365 -- If either range is True, return True
7366
7367 if Is_True (Left) or else Is_True (Right) then
7368 return True_Range;
7369 end if;
7370
7371 -- If either range is False (empty), return the other
7372
7373 if Is_False (Left) then
7374 return Right;
7375 elsif Is_False (Right) then
7376 return Left;
7377 end if;
7378
7379 -- Initialize result first entry from left or right operand depending
7380 -- on which starts with the lower range.
7381
7382 if Left (SLeft).Lo < Right (SRight).Lo then
7383 FEnt := Left (SLeft);
7384 SLeft := SLeft + 1;
7385 else
7386 FEnt := Right (SRight);
7387 SRight := SRight + 1;
7388 end if;
7389
7390 -- This loop eats ranges from left and right operands that are
7391 -- contiguous with the first range we are gathering.
7392
7393 loop
7394 -- Eat first entry in left operand if contiguous or overlapped by
7395 -- gathered first operand of result.
7396
7397 if SLeft <= Left'Last
7398 and then Left (SLeft).Lo <= FEnt.Hi + 1
7399 then
7400 FEnt.Hi := UI_Max (FEnt.Hi, Left (SLeft).Hi);
7401 SLeft := SLeft + 1;
7402
7403 -- Eat first entry in right operand if contiguous or overlapped by
7404 -- gathered right operand of result.
7405
7406 elsif SRight <= Right'Last
7407 and then Right (SRight).Lo <= FEnt.Hi + 1
7408 then
7409 FEnt.Hi := UI_Max (FEnt.Hi, Right (SRight).Hi);
7410 SRight := SRight + 1;
7411
7412 -- All done if no more entries to eat
7413
7414 else
7415 exit;
7416 end if;
7417 end loop;
7418
7419 -- Obtain result as the first entry we just computed, concatenated
7420 -- to the "or" of the remaining results (if one operand is empty,
7421 -- this will just concatenate with the other
7422
7423 return
7424 FEnt & (Left (SLeft .. Left'Last) or Right (SRight .. Right'Last));
7425 end "or";
7426
7427 -----------------
7428 -- Build_Range --
7429 -----------------
7430
7431 function Build_Range (Lo : Uint; Hi : Uint) return Node_Id is
7432 Result : Node_Id;
7433 begin
7434 Result :=
7435 Make_Range (Loc,
7436 Low_Bound => Build_Val (Lo),
7437 High_Bound => Build_Val (Hi));
7438 Set_Etype (Result, Btyp);
7439 Set_Analyzed (Result);
7440 return Result;
7441 end Build_Range;
7442
7443 ---------------
7444 -- Build_Val --
7445 ---------------
7446
7447 function Build_Val (V : Uint) return Node_Id is
7448 Result : Node_Id;
7449
7450 begin
7451 if Is_Enumeration_Type (Typ) then
7452 Result := Get_Enum_Lit_From_Pos (Typ, V, Loc);
7453 else
7454 Result := Make_Integer_Literal (Loc, V);
7455 end if;
7456
7457 Set_Etype (Result, Btyp);
7458 Set_Is_Static_Expression (Result);
7459 Set_Analyzed (Result);
7460 return Result;
7461 end Build_Val;
7462
7463 ---------------
7464 -- Get_RList --
7465 ---------------
7466
7467 function Get_RList (Exp : Node_Id) return RList is
7468 Op : Node_Kind;
7469 Val : Uint;
7470
7471 begin
7472 -- Static expression can only be true or false
7473
7474 if Is_OK_Static_Expression (Exp) then
7475 if Expr_Value (Exp) = 0 then
7476 return False_Range;
7477 else
7478 return True_Range;
7479 end if;
7480 end if;
7481
7482 -- Otherwise test node type
7483
7484 Op := Nkind (Exp);
7485
7486 case Op is
7487
7488 -- And
7489
7490 when N_Op_And | N_And_Then =>
7491 return Get_RList (Left_Opnd (Exp))
7492 and
7493 Get_RList (Right_Opnd (Exp));
7494
7495 -- Or
7496
7497 when N_Op_Or | N_Or_Else =>
7498 return Get_RList (Left_Opnd (Exp))
7499 or
7500 Get_RList (Right_Opnd (Exp));
7501
7502 -- Not
7503
7504 when N_Op_Not =>
7505 return not Get_RList (Right_Opnd (Exp));
7506
7507 -- Comparisons of type with static value
7508
7509 when N_Op_Compare =>
7510
7511 -- Type is left operand
7512
7513 if Is_Type_Ref (Left_Opnd (Exp))
7514 and then Is_OK_Static_Expression (Right_Opnd (Exp))
7515 then
7516 Val := Expr_Value (Right_Opnd (Exp));
7517
7518 -- Typ is right operand
7519
7520 elsif Is_Type_Ref (Right_Opnd (Exp))
7521 and then Is_OK_Static_Expression (Left_Opnd (Exp))
7522 then
7523 Val := Expr_Value (Left_Opnd (Exp));
7524
7525 -- Invert sense of comparison
7526
7527 case Op is
7528 when N_Op_Gt => Op := N_Op_Lt;
7529 when N_Op_Lt => Op := N_Op_Gt;
7530 when N_Op_Ge => Op := N_Op_Le;
7531 when N_Op_Le => Op := N_Op_Ge;
7532 when others => null;
7533 end case;
7534
7535 -- Other cases are non-static
7536
7537 else
7538 raise Non_Static;
7539 end if;
7540
7541 -- Construct range according to comparison operation
7542
7543 case Op is
7544 when N_Op_Eq =>
7545 return RList'(1 => REnt'(Val, Val));
7546
7547 when N_Op_Ge =>
7548 return RList'(1 => REnt'(Val, BHi));
7549
7550 when N_Op_Gt =>
7551 return RList'(1 => REnt'(Val + 1, BHi));
7552
7553 when N_Op_Le =>
7554 return RList'(1 => REnt'(BLo, Val));
7555
7556 when N_Op_Lt =>
7557 return RList'(1 => REnt'(BLo, Val - 1));
7558
7559 when N_Op_Ne =>
7560 return RList'(REnt'(BLo, Val - 1), REnt'(Val + 1, BHi));
7561
7562 when others =>
7563 raise Program_Error;
7564 end case;
7565
7566 -- Membership (IN)
7567
7568 when N_In =>
7569 if not Is_Type_Ref (Left_Opnd (Exp)) then
7570 raise Non_Static;
7571 end if;
7572
7573 if Present (Right_Opnd (Exp)) then
7574 return Membership_Entry (Right_Opnd (Exp));
7575 else
7576 return Membership_Entries (First (Alternatives (Exp)));
7577 end if;
7578
7579 -- Negative membership (NOT IN)
7580
7581 when N_Not_In =>
7582 if not Is_Type_Ref (Left_Opnd (Exp)) then
7583 raise Non_Static;
7584 end if;
7585
7586 if Present (Right_Opnd (Exp)) then
7587 return not Membership_Entry (Right_Opnd (Exp));
7588 else
7589 return not Membership_Entries (First (Alternatives (Exp)));
7590 end if;
7591
7592 -- Function call, may be call to static predicate
7593
7594 when N_Function_Call =>
7595 if Is_Entity_Name (Name (Exp)) then
7596 declare
7597 Ent : constant Entity_Id := Entity (Name (Exp));
7598 begin
7599 if Is_Predicate_Function (Ent)
7600 or else
7601 Is_Predicate_Function_M (Ent)
7602 then
7603 return Stat_Pred (Etype (First_Formal (Ent)));
7604 end if;
7605 end;
7606 end if;
7607
7608 -- Other function call cases are non-static
7609
7610 raise Non_Static;
7611
7612 -- Qualified expression, dig out the expression
7613
7614 when N_Qualified_Expression =>
7615 return Get_RList (Expression (Exp));
7616
7617 when N_Case_Expression =>
7618 declare
7619 Alt : Node_Id;
7620 Choices : List_Id;
7621 Dep : Node_Id;
7622
7623 begin
7624 if not Is_Entity_Name (Expression (Expr))
7625 or else Etype (Expression (Expr)) /= Typ
7626 then
7627 Error_Msg_N
7628 ("expression must denaote subtype", Expression (Expr));
7629 return False_Range;
7630 end if;
7631
7632 -- Collect discrete choices in all True alternatives
7633
7634 Choices := New_List;
7635 Alt := First (Alternatives (Exp));
7636 while Present (Alt) loop
7637 Dep := Expression (Alt);
7638
7639 if not Is_OK_Static_Expression (Dep) then
7640 raise Non_Static;
7641
7642 elsif Is_True (Expr_Value (Dep)) then
7643 Append_List_To (Choices,
7644 New_Copy_List (Discrete_Choices (Alt)));
7645 end if;
7646
7647 Next (Alt);
7648 end loop;
7649
7650 return Membership_Entries (First (Choices));
7651 end;
7652
7653 -- Expression with actions: if no actions, dig out expression
7654
7655 when N_Expression_With_Actions =>
7656 if Is_Empty_List (Actions (Exp)) then
7657 return Get_RList (Expression (Exp));
7658 else
7659 raise Non_Static;
7660 end if;
7661
7662 -- Xor operator
7663
7664 when N_Op_Xor =>
7665 return (Get_RList (Left_Opnd (Exp))
7666 and not Get_RList (Right_Opnd (Exp)))
7667 or (Get_RList (Right_Opnd (Exp))
7668 and not Get_RList (Left_Opnd (Exp)));
7669
7670 -- Any other node type is non-static
7671
7672 when others =>
7673 raise Non_Static;
7674 end case;
7675 end Get_RList;
7676
7677 ------------
7678 -- Hi_Val --
7679 ------------
7680
7681 function Hi_Val (N : Node_Id) return Uint is
7682 begin
7683 if Is_OK_Static_Expression (N) then
7684 return Expr_Value (N);
7685 else
7686 pragma Assert (Nkind (N) = N_Range);
7687 return Expr_Value (High_Bound (N));
7688 end if;
7689 end Hi_Val;
7690
7691 --------------
7692 -- Is_False --
7693 --------------
7694
7695 function Is_False (R : RList) return Boolean is
7696 begin
7697 return R'Length = 0;
7698 end Is_False;
7699
7700 -------------
7701 -- Is_True --
7702 -------------
7703
7704 function Is_True (R : RList) return Boolean is
7705 begin
7706 return R'Length = 1
7707 and then R (R'First).Lo = BLo
7708 and then R (R'First).Hi = BHi;
7709 end Is_True;
7710
7711 -----------------
7712 -- Is_Type_Ref --
7713 -----------------
7714
7715 function Is_Type_Ref (N : Node_Id) return Boolean is
7716 begin
7717 return Nkind (N) = N_Identifier
7718 and then Chars (N) = Nam
7719 and then Paren_Count (N) = 0;
7720 end Is_Type_Ref;
7721
7722 ------------
7723 -- Lo_Val --
7724 ------------
7725
7726 function Lo_Val (N : Node_Id) return Uint is
7727 begin
7728 if Is_OK_Static_Expression (N) then
7729 return Expr_Value (N);
7730 else
7731 pragma Assert (Nkind (N) = N_Range);
7732 return Expr_Value (Low_Bound (N));
7733 end if;
7734 end Lo_Val;
7735
7736 ------------------------
7737 -- Membership_Entries --
7738 ------------------------
7739
7740 function Membership_Entries (N : Node_Id) return RList is
7741 begin
7742 if No (Next (N)) then
7743 return Membership_Entry (N);
7744 else
7745 return Membership_Entry (N) or Membership_Entries (Next (N));
7746 end if;
7747 end Membership_Entries;
7748
7749 ----------------------
7750 -- Membership_Entry --
7751 ----------------------
7752
7753 function Membership_Entry (N : Node_Id) return RList is
7754 Val : Uint;
7755 SLo : Uint;
7756 SHi : Uint;
7757
7758 begin
7759 -- Range case
7760
7761 if Nkind (N) = N_Range then
7762 if not Is_OK_Static_Expression (Low_Bound (N))
7763 or else
7764 not Is_OK_Static_Expression (High_Bound (N))
7765 then
7766 raise Non_Static;
7767 else
7768 SLo := Expr_Value (Low_Bound (N));
7769 SHi := Expr_Value (High_Bound (N));
7770 return RList'(1 => REnt'(SLo, SHi));
7771 end if;
7772
7773 -- Static expression case
7774
7775 elsif Is_OK_Static_Expression (N) then
7776 Val := Expr_Value (N);
7777 return RList'(1 => REnt'(Val, Val));
7778
7779 -- Identifier (other than static expression) case
7780
7781 else pragma Assert (Nkind (N) = N_Identifier);
7782
7783 -- Type case
7784
7785 if Is_Type (Entity (N)) then
7786
7787 -- If type has predicates, process them
7788
7789 if Has_Predicates (Entity (N)) then
7790 return Stat_Pred (Entity (N));
7791
7792 -- For static subtype without predicates, get range
7793
7794 elsif Is_OK_Static_Subtype (Entity (N)) then
7795 SLo := Expr_Value (Type_Low_Bound (Entity (N)));
7796 SHi := Expr_Value (Type_High_Bound (Entity (N)));
7797 return RList'(1 => REnt'(SLo, SHi));
7798
7799 -- Any other type makes us non-static
7800
7801 else
7802 raise Non_Static;
7803 end if;
7804
7805 -- Any other kind of identifier in predicate (e.g. a non-static
7806 -- expression value) means this is not a static predicate.
7807
7808 else
7809 raise Non_Static;
7810 end if;
7811 end if;
7812 end Membership_Entry;
7813
7814 ---------------
7815 -- Stat_Pred --
7816 ---------------
7817
7818 function Stat_Pred (Typ : Entity_Id) return RList is
7819 begin
7820 -- Not static if type does not have static predicates
7821
7822 if not Has_Static_Predicate (Typ) then
7823 raise Non_Static;
7824 end if;
7825
7826 -- Otherwise we convert the predicate list to a range list
7827
7828 declare
7829 Spred : constant List_Id := Static_Discrete_Predicate (Typ);
7830 Result : RList (1 .. List_Length (Spred));
7831 P : Node_Id;
7832
7833 begin
7834 P := First (Static_Discrete_Predicate (Typ));
7835 for J in Result'Range loop
7836 Result (J) := REnt'(Lo_Val (P), Hi_Val (P));
7837 Next (P);
7838 end loop;
7839
7840 return Result;
7841 end;
7842 end Stat_Pred;
7843
7844 -- Start of processing for Build_Discrete_Static_Predicate
7845
7846 begin
7847 -- Establish bounds for the predicate
7848
7849 if Compile_Time_Known_Value (Type_Low_Bound (Typ)) then
7850 TLo := Expr_Value (Type_Low_Bound (Typ));
7851 else
7852 TLo := BLo;
7853 end if;
7854
7855 if Compile_Time_Known_Value (Type_High_Bound (Typ)) then
7856 THi := Expr_Value (Type_High_Bound (Typ));
7857 else
7858 THi := BHi;
7859 end if;
7860
7861 -- Analyze the expression to see if it is a static predicate
7862
7863 declare
7864 Ranges : constant RList := Get_RList (Expr);
7865 -- Range list from expression if it is static
7866
7867 Plist : List_Id;
7868
7869 begin
7870 -- Convert range list into a form for the static predicate. In the
7871 -- Ranges array, we just have raw ranges, these must be converted
7872 -- to properly typed and analyzed static expressions or range nodes.
7873
7874 -- Note: here we limit ranges to the ranges of the subtype, so that
7875 -- a predicate is always false for values outside the subtype. That
7876 -- seems fine, such values are invalid anyway, and considering them
7877 -- to fail the predicate seems allowed and friendly, and furthermore
7878 -- simplifies processing for case statements and loops.
7879
7880 Plist := New_List;
7881
7882 for J in Ranges'Range loop
7883 declare
7884 Lo : Uint := Ranges (J).Lo;
7885 Hi : Uint := Ranges (J).Hi;
7886
7887 begin
7888 -- Ignore completely out of range entry
7889
7890 if Hi < TLo or else Lo > THi then
7891 null;
7892
7893 -- Otherwise process entry
7894
7895 else
7896 -- Adjust out of range value to subtype range
7897
7898 if Lo < TLo then
7899 Lo := TLo;
7900 end if;
7901
7902 if Hi > THi then
7903 Hi := THi;
7904 end if;
7905
7906 -- Convert range into required form
7907
7908 Append_To (Plist, Build_Range (Lo, Hi));
7909 end if;
7910 end;
7911 end loop;
7912
7913 -- Processing was successful and all entries were static, so now we
7914 -- can store the result as the predicate list.
7915
7916 Set_Static_Discrete_Predicate (Typ, Plist);
7917
7918 -- The processing for static predicates put the expression into
7919 -- canonical form as a series of ranges. It also eliminated
7920 -- duplicates and collapsed and combined ranges. We might as well
7921 -- replace the alternatives list of the right operand of the
7922 -- membership test with the static predicate list, which will
7923 -- usually be more efficient.
7924
7925 declare
7926 New_Alts : constant List_Id := New_List;
7927 Old_Node : Node_Id;
7928 New_Node : Node_Id;
7929
7930 begin
7931 Old_Node := First (Plist);
7932 while Present (Old_Node) loop
7933 New_Node := New_Copy (Old_Node);
7934
7935 if Nkind (New_Node) = N_Range then
7936 Set_Low_Bound (New_Node, New_Copy (Low_Bound (Old_Node)));
7937 Set_High_Bound (New_Node, New_Copy (High_Bound (Old_Node)));
7938 end if;
7939
7940 Append_To (New_Alts, New_Node);
7941 Next (Old_Node);
7942 end loop;
7943
7944 -- If empty list, replace by False
7945
7946 if Is_Empty_List (New_Alts) then
7947 Rewrite (Expr, New_Occurrence_Of (Standard_False, Loc));
7948
7949 -- Else replace by set membership test
7950
7951 else
7952 Rewrite (Expr,
7953 Make_In (Loc,
7954 Left_Opnd => Make_Identifier (Loc, Nam),
7955 Right_Opnd => Empty,
7956 Alternatives => New_Alts));
7957
7958 -- Resolve new expression in function context
7959
7960 Install_Formals (Predicate_Function (Typ));
7961 Push_Scope (Predicate_Function (Typ));
7962 Analyze_And_Resolve (Expr, Standard_Boolean);
7963 Pop_Scope;
7964 end if;
7965 end;
7966 end;
7967
7968 -- If non-static, return doing nothing
7969
7970 exception
7971 when Non_Static =>
7972 return;
7973 end Build_Discrete_Static_Predicate;
7974
7975 --------------------------------
7976 -- Build_Export_Import_Pragma --
7977 --------------------------------
7978
7979 function Build_Export_Import_Pragma
7980 (Asp : Node_Id;
7981 Id : Entity_Id) return Node_Id
7982 is
7983 Asp_Id : constant Aspect_Id := Get_Aspect_Id (Asp);
7984 Expr : constant Node_Id := Expression (Asp);
7985 Loc : constant Source_Ptr := Sloc (Asp);
7986
7987 Args : List_Id;
7988 Conv : Node_Id;
7989 Conv_Arg : Node_Id;
7990 Dummy_1 : Node_Id;
7991 Dummy_2 : Node_Id;
7992 EN : Node_Id;
7993 LN : Node_Id;
7994 Prag : Node_Id;
7995
7996 Create_Pragma : Boolean := False;
7997 -- This flag is set when the aspect form is such that it warrants the
7998 -- creation of a corresponding pragma.
7999
8000 begin
8001 if Present (Expr) then
8002 if Error_Posted (Expr) then
8003 null;
8004
8005 elsif Is_True (Expr_Value (Expr)) then
8006 Create_Pragma := True;
8007 end if;
8008
8009 -- Otherwise the aspect defaults to True
8010
8011 else
8012 Create_Pragma := True;
8013 end if;
8014
8015 -- Nothing to do when the expression is False or is erroneous
8016
8017 if not Create_Pragma then
8018 return Empty;
8019 end if;
8020
8021 -- Obtain all interfacing aspects that apply to the related entity
8022
8023 Get_Interfacing_Aspects
8024 (Iface_Asp => Asp,
8025 Conv_Asp => Conv,
8026 EN_Asp => EN,
8027 Expo_Asp => Dummy_1,
8028 Imp_Asp => Dummy_2,
8029 LN_Asp => LN);
8030
8031 Args := New_List;
8032
8033 -- Handle the convention argument
8034
8035 if Present (Conv) then
8036 Conv_Arg := New_Copy_Tree (Expression (Conv));
8037
8038 -- Assume convention "Ada' when aspect Convention is missing
8039
8040 else
8041 Conv_Arg := Make_Identifier (Loc, Name_Ada);
8042 end if;
8043
8044 Append_To (Args,
8045 Make_Pragma_Argument_Association (Loc,
8046 Chars => Name_Convention,
8047 Expression => Conv_Arg));
8048
8049 -- Handle the entity argument
8050
8051 Append_To (Args,
8052 Make_Pragma_Argument_Association (Loc,
8053 Chars => Name_Entity,
8054 Expression => New_Occurrence_Of (Id, Loc)));
8055
8056 -- Handle the External_Name argument
8057
8058 if Present (EN) then
8059 Append_To (Args,
8060 Make_Pragma_Argument_Association (Loc,
8061 Chars => Name_External_Name,
8062 Expression => New_Copy_Tree (Expression (EN))));
8063 end if;
8064
8065 -- Handle the Link_Name argument
8066
8067 if Present (LN) then
8068 Append_To (Args,
8069 Make_Pragma_Argument_Association (Loc,
8070 Chars => Name_Link_Name,
8071 Expression => New_Copy_Tree (Expression (LN))));
8072 end if;
8073
8074 -- Generate:
8075 -- pragma Export/Import
8076 -- (Convention => <Conv>/Ada,
8077 -- Entity => <Id>,
8078 -- [External_Name => <EN>,]
8079 -- [Link_Name => <LN>]);
8080
8081 Prag :=
8082 Make_Pragma (Loc,
8083 Pragma_Identifier =>
8084 Make_Identifier (Loc, Chars (Identifier (Asp))),
8085 Pragma_Argument_Associations => Args);
8086
8087 -- Decorate the relevant aspect and the pragma
8088
8089 Set_Aspect_Rep_Item (Asp, Prag);
8090
8091 Set_Corresponding_Aspect (Prag, Asp);
8092 Set_From_Aspect_Specification (Prag);
8093 Set_Parent (Prag, Asp);
8094
8095 if Asp_Id = Aspect_Import and then Is_Subprogram (Id) then
8096 Set_Import_Pragma (Id, Prag);
8097 end if;
8098
8099 return Prag;
8100 end Build_Export_Import_Pragma;
8101
8102 -------------------------------
8103 -- Build_Predicate_Functions --
8104 -------------------------------
8105
8106 -- The procedures that are constructed here have the form:
8107
8108 -- function typPredicate (Ixxx : typ) return Boolean is
8109 -- begin
8110 -- return
8111 -- typ1Predicate (typ1 (Ixxx))
8112 -- and then typ2Predicate (typ2 (Ixxx))
8113 -- and then ...;
8114 -- exp1 and then exp2 and then ...
8115 -- end typPredicate;
8116
8117 -- Here exp1, and exp2 are expressions from Predicate pragmas. Note that
8118 -- this is the point at which these expressions get analyzed, providing the
8119 -- required delay, and typ1, typ2, are entities from which predicates are
8120 -- inherited. Note that we do NOT generate Check pragmas, that's because we
8121 -- use this function even if checks are off, e.g. for membership tests.
8122
8123 -- Note that the inherited predicates are evaluated first, as required by
8124 -- AI12-0071-1.
8125
8126 -- Note that Sem_Eval.Real_Or_String_Static_Predicate_Matches depends on
8127 -- the form of this return expression.
8128
8129 -- If the expression has at least one Raise_Expression, then we also build
8130 -- the typPredicateM version of the function, in which any occurrence of a
8131 -- Raise_Expression is converted to "return False".
8132
8133 procedure Build_Predicate_Functions (Typ : Entity_Id; N : Node_Id) is
8134 Loc : constant Source_Ptr := Sloc (Typ);
8135
8136 Expr : Node_Id;
8137 -- This is the expression for the result of the function. It is
8138 -- is build by connecting the component predicates with AND THEN.
8139
8140 Expr_M : Node_Id;
8141 -- This is the corresponding return expression for the Predicate_M
8142 -- function. It differs in that raise expressions are marked for
8143 -- special expansion (see Process_REs).
8144
8145 Object_Name : Name_Id;
8146 -- Name for argument of Predicate procedure. Note that we use the same
8147 -- name for both predicate functions. That way the reference within the
8148 -- predicate expression is the same in both functions.
8149
8150 Object_Entity : Entity_Id;
8151 -- Entity for argument of Predicate procedure
8152
8153 Object_Entity_M : Entity_Id;
8154 -- Entity for argument of separate Predicate procedure when exceptions
8155 -- are present in expression.
8156
8157 FDecl : Node_Id;
8158 -- The function declaration
8159
8160 SId : Entity_Id;
8161 -- Its entity
8162
8163 Raise_Expression_Present : Boolean := False;
8164 -- Set True if Expr has at least one Raise_Expression
8165
8166 procedure Add_Condition (Cond : Node_Id);
8167 -- Append Cond to Expr using "and then" (or just copy Cond to Expr if
8168 -- Expr is empty).
8169
8170 procedure Add_Predicates;
8171 -- Appends expressions for any Predicate pragmas in the rep item chain
8172 -- Typ to Expr. Note that we look only at items for this exact entity.
8173 -- Inheritance of predicates for the parent type is done by calling the
8174 -- Predicate_Function of the parent type, using Add_Call above.
8175
8176 procedure Add_Call (T : Entity_Id);
8177 -- Includes a call to the predicate function for type T in Expr if T
8178 -- has predicates and Predicate_Function (T) is non-empty.
8179
8180 function Process_RE (N : Node_Id) return Traverse_Result;
8181 -- Used in Process REs, tests if node N is a raise expression, and if
8182 -- so, marks it to be converted to return False.
8183
8184 procedure Process_REs is new Traverse_Proc (Process_RE);
8185 -- Marks any raise expressions in Expr_M to return False
8186
8187 function Test_RE (N : Node_Id) return Traverse_Result;
8188 -- Used in Test_REs, tests one node for being a raise expression, and if
8189 -- so sets Raise_Expression_Present True.
8190
8191 procedure Test_REs is new Traverse_Proc (Test_RE);
8192 -- Tests to see if Expr contains any raise expressions
8193
8194 --------------
8195 -- Add_Call --
8196 --------------
8197
8198 procedure Add_Call (T : Entity_Id) is
8199 Exp : Node_Id;
8200
8201 begin
8202 if Present (T) and then Present (Predicate_Function (T)) then
8203 Set_Has_Predicates (Typ);
8204
8205 -- Build the call to the predicate function of T
8206
8207 Exp :=
8208 Make_Predicate_Call
8209 (T, Convert_To (T, Make_Identifier (Loc, Object_Name)));
8210
8211 -- "and"-in the call to evolving expression
8212
8213 Add_Condition (Exp);
8214
8215 -- Output info message on inheritance if required. Note we do not
8216 -- give this information for generic actual types, since it is
8217 -- unwelcome noise in that case in instantiations. We also
8218 -- generally suppress the message in instantiations, and also
8219 -- if it involves internal names.
8220
8221 if Opt.List_Inherited_Aspects
8222 and then not Is_Generic_Actual_Type (Typ)
8223 and then Instantiation_Depth (Sloc (Typ)) = 0
8224 and then not Is_Internal_Name (Chars (T))
8225 and then not Is_Internal_Name (Chars (Typ))
8226 then
8227 Error_Msg_Sloc := Sloc (Predicate_Function (T));
8228 Error_Msg_Node_2 := T;
8229 Error_Msg_N ("info: & inherits predicate from & #?L?", Typ);
8230 end if;
8231 end if;
8232 end Add_Call;
8233
8234 -------------------
8235 -- Add_Condition --
8236 -------------------
8237
8238 procedure Add_Condition (Cond : Node_Id) is
8239 begin
8240 -- This is the first predicate expression
8241
8242 if No (Expr) then
8243 Expr := Cond;
8244
8245 -- Otherwise concatenate to the existing predicate expressions by
8246 -- using "and then".
8247
8248 else
8249 Expr :=
8250 Make_And_Then (Loc,
8251 Left_Opnd => Relocate_Node (Expr),
8252 Right_Opnd => Cond);
8253 end if;
8254 end Add_Condition;
8255
8256 --------------------
8257 -- Add_Predicates --
8258 --------------------
8259
8260 procedure Add_Predicates is
8261 procedure Add_Predicate (Prag : Node_Id);
8262 -- Concatenate the expression of predicate pragma Prag to Expr by
8263 -- using a short circuit "and then" operator.
8264
8265 -------------------
8266 -- Add_Predicate --
8267 -------------------
8268
8269 procedure Add_Predicate (Prag : Node_Id) is
8270 procedure Replace_Type_Reference (N : Node_Id);
8271 -- Replace a single occurrence N of the subtype name with a
8272 -- reference to the formal of the predicate function. N can be an
8273 -- identifier referencing the subtype, or a selected component,
8274 -- representing an appropriately qualified occurrence of the
8275 -- subtype name.
8276
8277 procedure Replace_Type_References is
8278 new Replace_Type_References_Generic (Replace_Type_Reference);
8279 -- Traverse an expression changing every occurrence of an
8280 -- identifier whose name matches the name of the subtype with a
8281 -- reference to the formal parameter of the predicate function.
8282
8283 ----------------------------
8284 -- Replace_Type_Reference --
8285 ----------------------------
8286
8287 procedure Replace_Type_Reference (N : Node_Id) is
8288 begin
8289 Rewrite (N, Make_Identifier (Sloc (N), Object_Name));
8290 -- Use the Sloc of the usage name, not the defining name
8291
8292 Set_Etype (N, Typ);
8293 Set_Entity (N, Object_Entity);
8294
8295 -- We want to treat the node as if it comes from source, so
8296 -- that ASIS will not ignore it.
8297
8298 Set_Comes_From_Source (N, True);
8299 end Replace_Type_Reference;
8300
8301 -- Local variables
8302
8303 Asp : constant Node_Id := Corresponding_Aspect (Prag);
8304 Arg1 : Node_Id;
8305 Arg2 : Node_Id;
8306
8307 -- Start of processing for Add_Predicate
8308
8309 begin
8310 -- Extract the arguments of the pragma. The expression itself
8311 -- is copied for use in the predicate function, to preserve the
8312 -- original version for ASIS use.
8313
8314 Arg1 := First (Pragma_Argument_Associations (Prag));
8315 Arg2 := Next (Arg1);
8316
8317 Arg1 := Get_Pragma_Arg (Arg1);
8318 Arg2 := New_Copy_Tree (Get_Pragma_Arg (Arg2));
8319
8320 -- When the predicate pragma applies to the current type or its
8321 -- full view, replace all occurrences of the subtype name with
8322 -- references to the formal parameter of the predicate function.
8323
8324 if Entity (Arg1) = Typ
8325 or else Full_View (Entity (Arg1)) = Typ
8326 then
8327 Replace_Type_References (Arg2, Typ);
8328
8329 -- If the predicate pragma comes from an aspect, replace the
8330 -- saved expression because we need the subtype references
8331 -- replaced for the calls to Preanalyze_Spec_Expression in
8332 -- Check_Aspect_At_xxx routines.
8333
8334 if Present (Asp) then
8335 Set_Entity (Identifier (Asp), New_Copy_Tree (Arg2));
8336 end if;
8337
8338 -- "and"-in the Arg2 condition to evolving expression
8339
8340 Add_Condition (Relocate_Node (Arg2));
8341 end if;
8342 end Add_Predicate;
8343
8344 -- Local variables
8345
8346 Ritem : Node_Id;
8347
8348 -- Start of processing for Add_Predicates
8349
8350 begin
8351 Ritem := First_Rep_Item (Typ);
8352 while Present (Ritem) loop
8353 if Nkind (Ritem) = N_Pragma
8354 and then Pragma_Name (Ritem) = Name_Predicate
8355 then
8356 Add_Predicate (Ritem);
8357
8358 -- If the type is declared in an inner package it may be frozen
8359 -- outside of the package, and the generated pragma has not been
8360 -- analyzed yet, so capture the expression for the predicate
8361 -- function at this point.
8362
8363 elsif Nkind (Ritem) = N_Aspect_Specification
8364 and then Present (Aspect_Rep_Item (Ritem))
8365 and then Scope (Typ) /= Current_Scope
8366 then
8367 declare
8368 Prag : constant Node_Id := Aspect_Rep_Item (Ritem);
8369
8370 begin
8371 if Nkind (Prag) = N_Pragma
8372 and then Pragma_Name (Prag) = Name_Predicate
8373 then
8374 Add_Predicate (Prag);
8375 end if;
8376 end;
8377 end if;
8378
8379 Next_Rep_Item (Ritem);
8380 end loop;
8381 end Add_Predicates;
8382
8383 ----------------
8384 -- Process_RE --
8385 ----------------
8386
8387 function Process_RE (N : Node_Id) return Traverse_Result is
8388 begin
8389 if Nkind (N) = N_Raise_Expression then
8390 Set_Convert_To_Return_False (N);
8391 return Skip;
8392 else
8393 return OK;
8394 end if;
8395 end Process_RE;
8396
8397 -------------
8398 -- Test_RE --
8399 -------------
8400
8401 function Test_RE (N : Node_Id) return Traverse_Result is
8402 begin
8403 if Nkind (N) = N_Raise_Expression then
8404 Raise_Expression_Present := True;
8405 return Abandon;
8406 else
8407 return OK;
8408 end if;
8409 end Test_RE;
8410
8411 -- Local variables
8412
8413 Save_Ghost_Mode : constant Ghost_Mode_Type := Ghost_Mode;
8414
8415 -- Start of processing for Build_Predicate_Functions
8416
8417 begin
8418 -- Return if already built or if type does not have predicates
8419
8420 SId := Predicate_Function (Typ);
8421 if not Has_Predicates (Typ)
8422 or else (Present (SId) and then Has_Completion (SId))
8423 then
8424 return;
8425 end if;
8426
8427 -- The related type may be subject to pragma Ghost. Set the mode now to
8428 -- ensure that the predicate functions are properly marked as Ghost.
8429
8430 Set_Ghost_Mode_From_Entity (Typ);
8431
8432 -- Prepare to construct predicate expression
8433
8434 Expr := Empty;
8435
8436 if Present (SId) then
8437 FDecl := Unit_Declaration_Node (SId);
8438
8439 else
8440 FDecl := Build_Predicate_Function_Declaration (Typ);
8441 SId := Defining_Entity (FDecl);
8442 end if;
8443
8444 -- Recover name of formal parameter of function that replaces references
8445 -- to the type in predicate expressions.
8446
8447 Object_Entity :=
8448 Defining_Identifier
8449 (First (Parameter_Specifications (Specification (FDecl))));
8450
8451 Object_Name := Chars (Object_Entity);
8452 Object_Entity_M := Make_Defining_Identifier (Loc, Chars => Object_Name);
8453
8454 -- Add predicates for ancestor if present. These must come before the
8455 -- ones for the current type, as required by AI12-0071-1.
8456
8457 declare
8458 Atyp : constant Entity_Id := Nearest_Ancestor (Typ);
8459 begin
8460 if Present (Atyp) then
8461 Add_Call (Atyp);
8462 end if;
8463 end;
8464
8465 -- Add Predicates for the current type
8466
8467 Add_Predicates;
8468
8469 -- Case where predicates are present
8470
8471 if Present (Expr) then
8472
8473 -- Test for raise expression present
8474
8475 Test_REs (Expr);
8476
8477 -- If raise expression is present, capture a copy of Expr for use
8478 -- in building the predicateM function version later on. For this
8479 -- copy we replace references to Object_Entity by Object_Entity_M.
8480
8481 if Raise_Expression_Present then
8482 declare
8483 Map : constant Elist_Id := New_Elmt_List;
8484 New_V : Entity_Id := Empty;
8485
8486 -- The unanalyzed expression will be copied and appear in
8487 -- both functions. Normally expressions do not declare new
8488 -- entities, but quantified expressions do, so we need to
8489 -- create new entities for their bound variables, to prevent
8490 -- multiple definitions in gigi.
8491
8492 function Reset_Loop_Variable (N : Node_Id)
8493 return Traverse_Result;
8494
8495 procedure Collect_Loop_Variables is
8496 new Traverse_Proc (Reset_Loop_Variable);
8497
8498 ------------------------
8499 -- Reset_Loop_Variable --
8500 ------------------------
8501
8502 function Reset_Loop_Variable (N : Node_Id)
8503 return Traverse_Result
8504 is
8505 begin
8506 if Nkind (N) = N_Iterator_Specification then
8507 New_V := Make_Defining_Identifier
8508 (Sloc (N), Chars (Defining_Identifier (N)));
8509
8510 Set_Defining_Identifier (N, New_V);
8511 end if;
8512
8513 return OK;
8514 end Reset_Loop_Variable;
8515
8516 begin
8517 Append_Elmt (Object_Entity, Map);
8518 Append_Elmt (Object_Entity_M, Map);
8519 Expr_M := New_Copy_Tree (Expr, Map => Map);
8520 Collect_Loop_Variables (Expr_M);
8521 end;
8522 end if;
8523
8524 -- Build the main predicate function
8525
8526 declare
8527 SIdB : constant Entity_Id :=
8528 Make_Defining_Identifier (Loc,
8529 Chars => New_External_Name (Chars (Typ), "Predicate"));
8530 -- The entity for the function body
8531
8532 Spec : Node_Id;
8533 FBody : Node_Id;
8534
8535 begin
8536
8537 -- The predicate function is shared between views of a type
8538
8539 if Is_Private_Type (Typ) and then Present (Full_View (Typ)) then
8540 Set_Predicate_Function (Full_View (Typ), SId);
8541 end if;
8542
8543 -- Mark the predicate function explicitly as Ghost because it does
8544 -- not come from source.
8545
8546 if Ghost_Mode > None then
8547 Set_Is_Ghost_Entity (SId);
8548 end if;
8549
8550 -- Build function body
8551
8552 Spec :=
8553 Make_Function_Specification (Loc,
8554 Defining_Unit_Name => SIdB,
8555 Parameter_Specifications => New_List (
8556 Make_Parameter_Specification (Loc,
8557 Defining_Identifier =>
8558 Make_Defining_Identifier (Loc, Object_Name),
8559 Parameter_Type =>
8560 New_Occurrence_Of (Typ, Loc))),
8561 Result_Definition =>
8562 New_Occurrence_Of (Standard_Boolean, Loc));
8563
8564 FBody :=
8565 Make_Subprogram_Body (Loc,
8566 Specification => Spec,
8567 Declarations => Empty_List,
8568 Handled_Statement_Sequence =>
8569 Make_Handled_Sequence_Of_Statements (Loc,
8570 Statements => New_List (
8571 Make_Simple_Return_Statement (Loc,
8572 Expression => Expr))));
8573
8574 -- If declaration has not been analyzed yet, Insert declaration
8575 -- before freeze node. Insert body itself after freeze node.
8576
8577 if not Analyzed (FDecl) then
8578 Insert_Before_And_Analyze (N, FDecl);
8579 end if;
8580
8581 Insert_After_And_Analyze (N, FBody);
8582
8583 -- Static predicate functions are always side-effect free, and
8584 -- in most cases dynamic predicate functions are as well. Mark
8585 -- them as such whenever possible, so redundant predicate checks
8586 -- can be optimized. If there is a variable reference within the
8587 -- expression, the function is not pure.
8588
8589 if Expander_Active then
8590 Set_Is_Pure (SId,
8591 Side_Effect_Free (Expr, Variable_Ref => True));
8592 Set_Is_Inlined (SId);
8593 end if;
8594 end;
8595
8596 -- Test for raise expressions present and if so build M version
8597
8598 if Raise_Expression_Present then
8599 declare
8600 SId : constant Entity_Id :=
8601 Make_Defining_Identifier (Loc,
8602 Chars => New_External_Name (Chars (Typ), "PredicateM"));
8603 -- The entity for the function spec
8604
8605 SIdB : constant Entity_Id :=
8606 Make_Defining_Identifier (Loc,
8607 Chars => New_External_Name (Chars (Typ), "PredicateM"));
8608 -- The entity for the function body
8609
8610 Spec : Node_Id;
8611 FBody : Node_Id;
8612 FDecl : Node_Id;
8613 BTemp : Entity_Id;
8614
8615 begin
8616 -- Mark any raise expressions for special expansion
8617
8618 Process_REs (Expr_M);
8619
8620 -- Build function declaration
8621
8622 Set_Ekind (SId, E_Function);
8623 Set_Is_Predicate_Function_M (SId);
8624 Set_Predicate_Function_M (Typ, SId);
8625
8626 -- The predicate function is shared between views of a type
8627
8628 if Is_Private_Type (Typ) and then Present (Full_View (Typ)) then
8629 Set_Predicate_Function_M (Full_View (Typ), SId);
8630 end if;
8631
8632 -- Mark the predicate function explicitly as Ghost because it
8633 -- does not come from source.
8634
8635 if Ghost_Mode > None then
8636 Set_Is_Ghost_Entity (SId);
8637 end if;
8638
8639 Spec :=
8640 Make_Function_Specification (Loc,
8641 Defining_Unit_Name => SId,
8642 Parameter_Specifications => New_List (
8643 Make_Parameter_Specification (Loc,
8644 Defining_Identifier => Object_Entity_M,
8645 Parameter_Type => New_Occurrence_Of (Typ, Loc))),
8646 Result_Definition =>
8647 New_Occurrence_Of (Standard_Boolean, Loc));
8648
8649 FDecl :=
8650 Make_Subprogram_Declaration (Loc,
8651 Specification => Spec);
8652
8653 -- Build function body
8654
8655 Spec :=
8656 Make_Function_Specification (Loc,
8657 Defining_Unit_Name => SIdB,
8658 Parameter_Specifications => New_List (
8659 Make_Parameter_Specification (Loc,
8660 Defining_Identifier =>
8661 Make_Defining_Identifier (Loc, Object_Name),
8662 Parameter_Type =>
8663 New_Occurrence_Of (Typ, Loc))),
8664 Result_Definition =>
8665 New_Occurrence_Of (Standard_Boolean, Loc));
8666
8667 -- Build the body, we declare the boolean expression before
8668 -- doing the return, because we are not really confident of
8669 -- what happens if a return appears within a return.
8670
8671 BTemp :=
8672 Make_Defining_Identifier (Loc,
8673 Chars => New_Internal_Name ('B'));
8674
8675 FBody :=
8676 Make_Subprogram_Body (Loc,
8677 Specification => Spec,
8678
8679 Declarations => New_List (
8680 Make_Object_Declaration (Loc,
8681 Defining_Identifier => BTemp,
8682 Constant_Present => True,
8683 Object_Definition =>
8684 New_Occurrence_Of (Standard_Boolean, Loc),
8685 Expression => Expr_M)),
8686
8687 Handled_Statement_Sequence =>
8688 Make_Handled_Sequence_Of_Statements (Loc,
8689 Statements => New_List (
8690 Make_Simple_Return_Statement (Loc,
8691 Expression => New_Occurrence_Of (BTemp, Loc)))));
8692
8693 -- Insert declaration before freeze node and body after
8694
8695 Insert_Before_And_Analyze (N, FDecl);
8696 Insert_After_And_Analyze (N, FBody);
8697 end;
8698 end if;
8699
8700 -- See if we have a static predicate. Note that the answer may be
8701 -- yes even if we have an explicit Dynamic_Predicate present.
8702
8703 declare
8704 PS : Boolean;
8705 EN : Node_Id;
8706
8707 begin
8708 if not Is_Scalar_Type (Typ) and then not Is_String_Type (Typ) then
8709 PS := False;
8710 else
8711 PS := Is_Predicate_Static (Expr, Object_Name);
8712 end if;
8713
8714 -- Case where we have a predicate-static aspect
8715
8716 if PS then
8717
8718 -- We don't set Has_Static_Predicate_Aspect, since we can have
8719 -- any of the three cases (Predicate, Dynamic_Predicate, or
8720 -- Static_Predicate) generating a predicate with an expression
8721 -- that is predicate-static. We just indicate that we have a
8722 -- predicate that can be treated as static.
8723
8724 Set_Has_Static_Predicate (Typ);
8725
8726 -- For discrete subtype, build the static predicate list
8727
8728 if Is_Discrete_Type (Typ) then
8729 Build_Discrete_Static_Predicate (Typ, Expr, Object_Name);
8730
8731 -- If we don't get a static predicate list, it means that we
8732 -- have a case where this is not possible, most typically in
8733 -- the case where we inherit a dynamic predicate. We do not
8734 -- consider this an error, we just leave the predicate as
8735 -- dynamic. But if we do succeed in building the list, then
8736 -- we mark the predicate as static.
8737
8738 if No (Static_Discrete_Predicate (Typ)) then
8739 Set_Has_Static_Predicate (Typ, False);
8740 end if;
8741
8742 -- For real or string subtype, save predicate expression
8743
8744 elsif Is_Real_Type (Typ) or else Is_String_Type (Typ) then
8745 Set_Static_Real_Or_String_Predicate (Typ, Expr);
8746 end if;
8747
8748 -- Case of dynamic predicate (expression is not predicate-static)
8749
8750 else
8751 -- Again, we don't set Has_Dynamic_Predicate_Aspect, since that
8752 -- is only set if we have an explicit Dynamic_Predicate aspect
8753 -- given. Here we may simply have a Predicate aspect where the
8754 -- expression happens not to be predicate-static.
8755
8756 -- Emit an error when the predicate is categorized as static
8757 -- but its expression is not predicate-static.
8758
8759 -- First a little fiddling to get a nice location for the
8760 -- message. If the expression is of the form (A and then B),
8761 -- where A is an inherited predicate, then use the right
8762 -- operand for the Sloc. This avoids getting confused by a call
8763 -- to an inherited predicate with a less convenient source
8764 -- location.
8765
8766 EN := Expr;
8767 while Nkind (EN) = N_And_Then
8768 and then Nkind (Left_Opnd (EN)) = N_Function_Call
8769 and then Is_Predicate_Function
8770 (Entity (Name (Left_Opnd (EN))))
8771 loop
8772 EN := Right_Opnd (EN);
8773 end loop;
8774
8775 -- Now post appropriate message
8776
8777 if Has_Static_Predicate_Aspect (Typ) then
8778 if Is_Scalar_Type (Typ) or else Is_String_Type (Typ) then
8779 Error_Msg_F
8780 ("expression is not predicate-static (RM 3.2.4(16-22))",
8781 EN);
8782 else
8783 Error_Msg_F
8784 ("static predicate requires scalar or string type", EN);
8785 end if;
8786 end if;
8787 end if;
8788 end;
8789 end if;
8790
8791 Ghost_Mode := Save_Ghost_Mode;
8792 end Build_Predicate_Functions;
8793
8794 ------------------------------------------
8795 -- Build_Predicate_Function_Declaration --
8796 ------------------------------------------
8797
8798 function Build_Predicate_Function_Declaration
8799 (Typ : Entity_Id) return Node_Id
8800 is
8801 Loc : constant Source_Ptr := Sloc (Typ);
8802
8803 Object_Entity : constant Entity_Id :=
8804 Make_Defining_Identifier (Loc,
8805 Chars => New_Internal_Name ('I'));
8806
8807 -- The formal parameter of the function
8808
8809 SId : constant Entity_Id :=
8810 Make_Defining_Identifier (Loc,
8811 Chars => New_External_Name (Chars (Typ), "Predicate"));
8812
8813 -- The entity for the function spec
8814
8815 FDecl : Node_Id;
8816 Spec : Node_Id;
8817
8818 begin
8819 Spec :=
8820 Make_Function_Specification (Loc,
8821 Defining_Unit_Name => SId,
8822 Parameter_Specifications => New_List (
8823 Make_Parameter_Specification (Loc,
8824 Defining_Identifier => Object_Entity,
8825 Parameter_Type => New_Occurrence_Of (Typ, Loc))),
8826 Result_Definition =>
8827 New_Occurrence_Of (Standard_Boolean, Loc));
8828
8829 FDecl := Make_Subprogram_Declaration (Loc, Specification => Spec);
8830
8831 Set_Ekind (SId, E_Function);
8832 Set_Etype (SId, Standard_Boolean);
8833 Set_Is_Internal (SId);
8834 Set_Is_Predicate_Function (SId);
8835 Set_Predicate_Function (Typ, SId);
8836
8837 if Comes_From_Source (Typ) then
8838 Insert_After (Parent (Typ), FDecl);
8839 else
8840 Insert_After (Parent (Base_Type (Typ)), FDecl);
8841 end if;
8842
8843 Analyze (FDecl);
8844
8845 return FDecl;
8846 end Build_Predicate_Function_Declaration;
8847
8848 -----------------------------------------
8849 -- Check_Aspect_At_End_Of_Declarations --
8850 -----------------------------------------
8851
8852 procedure Check_Aspect_At_End_Of_Declarations (ASN : Node_Id) is
8853 Ent : constant Entity_Id := Entity (ASN);
8854 Ident : constant Node_Id := Identifier (ASN);
8855 A_Id : constant Aspect_Id := Get_Aspect_Id (Chars (Ident));
8856
8857 End_Decl_Expr : constant Node_Id := Entity (Ident);
8858 -- Expression to be analyzed at end of declarations
8859
8860 Freeze_Expr : constant Node_Id := Expression (ASN);
8861 -- Expression from call to Check_Aspect_At_Freeze_Point
8862
8863 T : constant Entity_Id := Etype (Freeze_Expr);
8864 -- Type required for preanalyze call
8865
8866 Err : Boolean;
8867 -- Set False if error
8868
8869 -- On entry to this procedure, Entity (Ident) contains a copy of the
8870 -- original expression from the aspect, saved for this purpose, and
8871 -- but Expression (Ident) is a preanalyzed copy of the expression,
8872 -- preanalyzed just after the freeze point.
8873
8874 procedure Check_Overloaded_Name;
8875 -- For aspects whose expression is simply a name, this routine checks if
8876 -- the name is overloaded or not. If so, it verifies there is an
8877 -- interpretation that matches the entity obtained at the freeze point,
8878 -- otherwise the compiler complains.
8879
8880 ---------------------------
8881 -- Check_Overloaded_Name --
8882 ---------------------------
8883
8884 procedure Check_Overloaded_Name is
8885 begin
8886 if not Is_Overloaded (End_Decl_Expr) then
8887 Err := not Is_Entity_Name (End_Decl_Expr)
8888 or else Entity (End_Decl_Expr) /= Entity (Freeze_Expr);
8889
8890 else
8891 Err := True;
8892
8893 declare
8894 Index : Interp_Index;
8895 It : Interp;
8896
8897 begin
8898 Get_First_Interp (End_Decl_Expr, Index, It);
8899 while Present (It.Typ) loop
8900 if It.Nam = Entity (Freeze_Expr) then
8901 Err := False;
8902 exit;
8903 end if;
8904
8905 Get_Next_Interp (Index, It);
8906 end loop;
8907 end;
8908 end if;
8909 end Check_Overloaded_Name;
8910
8911 -- Start of processing for Check_Aspect_At_End_Of_Declarations
8912
8913 begin
8914 -- In an instance we do not perform the consistency check between freeze
8915 -- point and end of declarations, because it was done already in the
8916 -- analysis of the generic. Furthermore, the delayed analysis of an
8917 -- aspect of the instance may produce spurious errors when the generic
8918 -- is a child unit that references entities in the parent (which might
8919 -- not be in scope at the freeze point of the instance).
8920
8921 if In_Instance then
8922 return;
8923
8924 -- Case of aspects Dimension, Dimension_System and Synchronization
8925
8926 elsif A_Id = Aspect_Synchronization then
8927 return;
8928
8929 -- Case of stream attributes, just have to compare entities. However,
8930 -- the expression is just a name (possibly overloaded), and there may
8931 -- be stream operations declared for unrelated types, so we just need
8932 -- to verify that one of these interpretations is the one available at
8933 -- at the freeze point.
8934
8935 elsif A_Id = Aspect_Input or else
8936 A_Id = Aspect_Output or else
8937 A_Id = Aspect_Read or else
8938 A_Id = Aspect_Write
8939 then
8940 Analyze (End_Decl_Expr);
8941 Check_Overloaded_Name;
8942
8943 elsif A_Id = Aspect_Variable_Indexing or else
8944 A_Id = Aspect_Constant_Indexing or else
8945 A_Id = Aspect_Default_Iterator or else
8946 A_Id = Aspect_Iterator_Element
8947 then
8948 -- Make type unfrozen before analysis, to prevent spurious errors
8949 -- about late attributes.
8950
8951 Set_Is_Frozen (Ent, False);
8952 Analyze (End_Decl_Expr);
8953 Set_Is_Frozen (Ent, True);
8954
8955 -- If the end of declarations comes before any other freeze
8956 -- point, the Freeze_Expr is not analyzed: no check needed.
8957
8958 if Analyzed (Freeze_Expr) and then not In_Instance then
8959 Check_Overloaded_Name;
8960 else
8961 Err := False;
8962 end if;
8963
8964 -- All other cases
8965
8966 else
8967 -- Indicate that the expression comes from an aspect specification,
8968 -- which is used in subsequent analysis even if expansion is off.
8969
8970 Set_Parent (End_Decl_Expr, ASN);
8971
8972 -- In a generic context the aspect expressions have not been
8973 -- preanalyzed, so do it now. There are no conformance checks
8974 -- to perform in this case.
8975
8976 if No (T) then
8977 Check_Aspect_At_Freeze_Point (ASN);
8978 return;
8979
8980 -- The default values attributes may be defined in the private part,
8981 -- and the analysis of the expression may take place when only the
8982 -- partial view is visible. The expression must be scalar, so use
8983 -- the full view to resolve.
8984
8985 elsif (A_Id = Aspect_Default_Value
8986 or else
8987 A_Id = Aspect_Default_Component_Value)
8988 and then Is_Private_Type (T)
8989 then
8990 Preanalyze_Spec_Expression (End_Decl_Expr, Full_View (T));
8991
8992 else
8993 Preanalyze_Spec_Expression (End_Decl_Expr, T);
8994 end if;
8995
8996 Err := not Fully_Conformant_Expressions (End_Decl_Expr, Freeze_Expr);
8997 end if;
8998
8999 -- Output error message if error. Force error on aspect specification
9000 -- even if there is an error on the expression itself.
9001
9002 if Err then
9003 Error_Msg_NE
9004 ("!visibility of aspect for& changes after freeze point",
9005 ASN, Ent);
9006 Error_Msg_NE
9007 ("info: & is frozen here, aspects evaluated at this point??",
9008 Freeze_Node (Ent), Ent);
9009 end if;
9010 end Check_Aspect_At_End_Of_Declarations;
9011
9012 ----------------------------------
9013 -- Check_Aspect_At_Freeze_Point --
9014 ----------------------------------
9015
9016 procedure Check_Aspect_At_Freeze_Point (ASN : Node_Id) is
9017 Ident : constant Node_Id := Identifier (ASN);
9018 -- Identifier (use Entity field to save expression)
9019
9020 A_Id : constant Aspect_Id := Get_Aspect_Id (Chars (Ident));
9021
9022 T : Entity_Id := Empty;
9023 -- Type required for preanalyze call
9024
9025 begin
9026 -- On entry to this procedure, Entity (Ident) contains a copy of the
9027 -- original expression from the aspect, saved for this purpose.
9028
9029 -- On exit from this procedure Entity (Ident) is unchanged, still
9030 -- containing that copy, but Expression (Ident) is a preanalyzed copy
9031 -- of the expression, preanalyzed just after the freeze point.
9032
9033 -- Make a copy of the expression to be preanalyzed
9034
9035 Set_Expression (ASN, New_Copy_Tree (Entity (Ident)));
9036
9037 -- Find type for preanalyze call
9038
9039 case A_Id is
9040
9041 -- No_Aspect should be impossible
9042
9043 when No_Aspect =>
9044 raise Program_Error;
9045
9046 -- Aspects taking an optional boolean argument
9047
9048 when Boolean_Aspects |
9049 Library_Unit_Aspects =>
9050
9051 T := Standard_Boolean;
9052
9053 -- Aspects corresponding to attribute definition clauses
9054
9055 when Aspect_Address =>
9056 T := RTE (RE_Address);
9057
9058 when Aspect_Attach_Handler =>
9059 T := RTE (RE_Interrupt_ID);
9060
9061 when Aspect_Bit_Order | Aspect_Scalar_Storage_Order =>
9062 T := RTE (RE_Bit_Order);
9063
9064 when Aspect_Convention =>
9065 return;
9066
9067 when Aspect_CPU =>
9068 T := RTE (RE_CPU_Range);
9069
9070 -- Default_Component_Value is resolved with the component type
9071
9072 when Aspect_Default_Component_Value =>
9073 T := Component_Type (Entity (ASN));
9074
9075 when Aspect_Default_Storage_Pool =>
9076 T := Class_Wide_Type (RTE (RE_Root_Storage_Pool));
9077
9078 -- Default_Value is resolved with the type entity in question
9079
9080 when Aspect_Default_Value =>
9081 T := Entity (ASN);
9082
9083 when Aspect_Dispatching_Domain =>
9084 T := RTE (RE_Dispatching_Domain);
9085
9086 when Aspect_External_Tag =>
9087 T := Standard_String;
9088
9089 when Aspect_External_Name =>
9090 T := Standard_String;
9091
9092 when Aspect_Link_Name =>
9093 T := Standard_String;
9094
9095 when Aspect_Priority | Aspect_Interrupt_Priority =>
9096 T := Standard_Integer;
9097
9098 when Aspect_Relative_Deadline =>
9099 T := RTE (RE_Time_Span);
9100
9101 when Aspect_Small =>
9102 T := Universal_Real;
9103
9104 -- For a simple storage pool, we have to retrieve the type of the
9105 -- pool object associated with the aspect's corresponding attribute
9106 -- definition clause.
9107
9108 when Aspect_Simple_Storage_Pool =>
9109 T := Etype (Expression (Aspect_Rep_Item (ASN)));
9110
9111 when Aspect_Storage_Pool =>
9112 T := Class_Wide_Type (RTE (RE_Root_Storage_Pool));
9113
9114 when Aspect_Alignment |
9115 Aspect_Component_Size |
9116 Aspect_Machine_Radix |
9117 Aspect_Object_Size |
9118 Aspect_Size |
9119 Aspect_Storage_Size |
9120 Aspect_Stream_Size |
9121 Aspect_Value_Size =>
9122 T := Any_Integer;
9123
9124 when Aspect_Linker_Section =>
9125 T := Standard_String;
9126
9127 when Aspect_Synchronization =>
9128 return;
9129
9130 -- Special case, the expression of these aspects is just an entity
9131 -- that does not need any resolution, so just analyze.
9132
9133 when Aspect_Input |
9134 Aspect_Output |
9135 Aspect_Read |
9136 Aspect_Suppress |
9137 Aspect_Unsuppress |
9138 Aspect_Warnings |
9139 Aspect_Write =>
9140 Analyze (Expression (ASN));
9141 return;
9142
9143 -- Same for Iterator aspects, where the expression is a function
9144 -- name. Legality rules are checked separately.
9145
9146 when Aspect_Constant_Indexing |
9147 Aspect_Default_Iterator |
9148 Aspect_Iterator_Element |
9149 Aspect_Variable_Indexing =>
9150 Analyze (Expression (ASN));
9151 return;
9152
9153 -- Ditto for Iterable, legality checks in Validate_Iterable_Aspect.
9154
9155 when Aspect_Iterable =>
9156 T := Entity (ASN);
9157
9158 declare
9159 Cursor : constant Entity_Id := Get_Cursor_Type (ASN, T);
9160 Assoc : Node_Id;
9161 Expr : Node_Id;
9162
9163 begin
9164 if Cursor = Any_Type then
9165 return;
9166 end if;
9167
9168 Assoc := First (Component_Associations (Expression (ASN)));
9169 while Present (Assoc) loop
9170 Expr := Expression (Assoc);
9171 Analyze (Expr);
9172
9173 if not Error_Posted (Expr) then
9174 Resolve_Iterable_Operation
9175 (Expr, Cursor, T, Chars (First (Choices (Assoc))));
9176 end if;
9177
9178 Next (Assoc);
9179 end loop;
9180 end;
9181
9182 return;
9183
9184 -- Invariant/Predicate take boolean expressions
9185
9186 when Aspect_Dynamic_Predicate |
9187 Aspect_Invariant |
9188 Aspect_Predicate |
9189 Aspect_Static_Predicate |
9190 Aspect_Type_Invariant =>
9191 T := Standard_Boolean;
9192
9193 when Aspect_Predicate_Failure =>
9194 T := Standard_String;
9195
9196 -- Here is the list of aspects that don't require delay analysis
9197
9198 when Aspect_Abstract_State |
9199 Aspect_Annotate |
9200 Aspect_Async_Readers |
9201 Aspect_Async_Writers |
9202 Aspect_Constant_After_Elaboration |
9203 Aspect_Contract_Cases |
9204 Aspect_Default_Initial_Condition |
9205 Aspect_Depends |
9206 Aspect_Dimension |
9207 Aspect_Dimension_System |
9208 Aspect_Effective_Reads |
9209 Aspect_Effective_Writes |
9210 Aspect_Extensions_Visible |
9211 Aspect_Ghost |
9212 Aspect_Global |
9213 Aspect_Implicit_Dereference |
9214 Aspect_Initial_Condition |
9215 Aspect_Initializes |
9216 Aspect_Obsolescent |
9217 Aspect_Part_Of |
9218 Aspect_Post |
9219 Aspect_Postcondition |
9220 Aspect_Pre |
9221 Aspect_Precondition |
9222 Aspect_Refined_Depends |
9223 Aspect_Refined_Global |
9224 Aspect_Refined_Post |
9225 Aspect_Refined_State |
9226 Aspect_SPARK_Mode |
9227 Aspect_Test_Case |
9228 Aspect_Unimplemented |
9229 Aspect_Volatile_Function =>
9230 raise Program_Error;
9231
9232 end case;
9233
9234 -- Do the preanalyze call
9235
9236 Preanalyze_Spec_Expression (Expression (ASN), T);
9237 end Check_Aspect_At_Freeze_Point;
9238
9239 -----------------------------------
9240 -- Check_Constant_Address_Clause --
9241 -----------------------------------
9242
9243 procedure Check_Constant_Address_Clause
9244 (Expr : Node_Id;
9245 U_Ent : Entity_Id)
9246 is
9247 procedure Check_At_Constant_Address (Nod : Node_Id);
9248 -- Checks that the given node N represents a name whose 'Address is
9249 -- constant (in the same sense as OK_Constant_Address_Clause, i.e. the
9250 -- address value is the same at the point of declaration of U_Ent and at
9251 -- the time of elaboration of the address clause.
9252
9253 procedure Check_Expr_Constants (Nod : Node_Id);
9254 -- Checks that Nod meets the requirements for a constant address clause
9255 -- in the sense of the enclosing procedure.
9256
9257 procedure Check_List_Constants (Lst : List_Id);
9258 -- Check that all elements of list Lst meet the requirements for a
9259 -- constant address clause in the sense of the enclosing procedure.
9260
9261 -------------------------------
9262 -- Check_At_Constant_Address --
9263 -------------------------------
9264
9265 procedure Check_At_Constant_Address (Nod : Node_Id) is
9266 begin
9267 if Is_Entity_Name (Nod) then
9268 if Present (Address_Clause (Entity ((Nod)))) then
9269 Error_Msg_NE
9270 ("invalid address clause for initialized object &!",
9271 Nod, U_Ent);
9272 Error_Msg_NE
9273 ("address for& cannot" &
9274 " depend on another address clause! (RM 13.1(22))!",
9275 Nod, U_Ent);
9276
9277 elsif In_Same_Source_Unit (Entity (Nod), U_Ent)
9278 and then Sloc (U_Ent) < Sloc (Entity (Nod))
9279 then
9280 Error_Msg_NE
9281 ("invalid address clause for initialized object &!",
9282 Nod, U_Ent);
9283 Error_Msg_Node_2 := U_Ent;
9284 Error_Msg_NE
9285 ("\& must be defined before & (RM 13.1(22))!",
9286 Nod, Entity (Nod));
9287 end if;
9288
9289 elsif Nkind (Nod) = N_Selected_Component then
9290 declare
9291 T : constant Entity_Id := Etype (Prefix (Nod));
9292
9293 begin
9294 if (Is_Record_Type (T)
9295 and then Has_Discriminants (T))
9296 or else
9297 (Is_Access_Type (T)
9298 and then Is_Record_Type (Designated_Type (T))
9299 and then Has_Discriminants (Designated_Type (T)))
9300 then
9301 Error_Msg_NE
9302 ("invalid address clause for initialized object &!",
9303 Nod, U_Ent);
9304 Error_Msg_N
9305 ("\address cannot depend on component" &
9306 " of discriminated record (RM 13.1(22))!",
9307 Nod);
9308 else
9309 Check_At_Constant_Address (Prefix (Nod));
9310 end if;
9311 end;
9312
9313 elsif Nkind (Nod) = N_Indexed_Component then
9314 Check_At_Constant_Address (Prefix (Nod));
9315 Check_List_Constants (Expressions (Nod));
9316
9317 else
9318 Check_Expr_Constants (Nod);
9319 end if;
9320 end Check_At_Constant_Address;
9321
9322 --------------------------
9323 -- Check_Expr_Constants --
9324 --------------------------
9325
9326 procedure Check_Expr_Constants (Nod : Node_Id) is
9327 Loc_U_Ent : constant Source_Ptr := Sloc (U_Ent);
9328 Ent : Entity_Id := Empty;
9329
9330 begin
9331 if Nkind (Nod) in N_Has_Etype
9332 and then Etype (Nod) = Any_Type
9333 then
9334 return;
9335 end if;
9336
9337 case Nkind (Nod) is
9338 when N_Empty | N_Error =>
9339 return;
9340
9341 when N_Identifier | N_Expanded_Name =>
9342 Ent := Entity (Nod);
9343
9344 -- We need to look at the original node if it is different
9345 -- from the node, since we may have rewritten things and
9346 -- substituted an identifier representing the rewrite.
9347
9348 if Original_Node (Nod) /= Nod then
9349 Check_Expr_Constants (Original_Node (Nod));
9350
9351 -- If the node is an object declaration without initial
9352 -- value, some code has been expanded, and the expression
9353 -- is not constant, even if the constituents might be
9354 -- acceptable, as in A'Address + offset.
9355
9356 if Ekind (Ent) = E_Variable
9357 and then
9358 Nkind (Declaration_Node (Ent)) = N_Object_Declaration
9359 and then
9360 No (Expression (Declaration_Node (Ent)))
9361 then
9362 Error_Msg_NE
9363 ("invalid address clause for initialized object &!",
9364 Nod, U_Ent);
9365
9366 -- If entity is constant, it may be the result of expanding
9367 -- a check. We must verify that its declaration appears
9368 -- before the object in question, else we also reject the
9369 -- address clause.
9370
9371 elsif Ekind (Ent) = E_Constant
9372 and then In_Same_Source_Unit (Ent, U_Ent)
9373 and then Sloc (Ent) > Loc_U_Ent
9374 then
9375 Error_Msg_NE
9376 ("invalid address clause for initialized object &!",
9377 Nod, U_Ent);
9378 end if;
9379
9380 return;
9381 end if;
9382
9383 -- Otherwise look at the identifier and see if it is OK
9384
9385 if Ekind_In (Ent, E_Named_Integer, E_Named_Real)
9386 or else Is_Type (Ent)
9387 then
9388 return;
9389
9390 elsif Ekind_In (Ent, E_Constant, E_In_Parameter) then
9391
9392 -- This is the case where we must have Ent defined before
9393 -- U_Ent. Clearly if they are in different units this
9394 -- requirement is met since the unit containing Ent is
9395 -- already processed.
9396
9397 if not In_Same_Source_Unit (Ent, U_Ent) then
9398 return;
9399
9400 -- Otherwise location of Ent must be before the location
9401 -- of U_Ent, that's what prior defined means.
9402
9403 elsif Sloc (Ent) < Loc_U_Ent then
9404 return;
9405
9406 else
9407 Error_Msg_NE
9408 ("invalid address clause for initialized object &!",
9409 Nod, U_Ent);
9410 Error_Msg_Node_2 := U_Ent;
9411 Error_Msg_NE
9412 ("\& must be defined before & (RM 13.1(22))!",
9413 Nod, Ent);
9414 end if;
9415
9416 elsif Nkind (Original_Node (Nod)) = N_Function_Call then
9417 Check_Expr_Constants (Original_Node (Nod));
9418
9419 else
9420 Error_Msg_NE
9421 ("invalid address clause for initialized object &!",
9422 Nod, U_Ent);
9423
9424 if Comes_From_Source (Ent) then
9425 Error_Msg_NE
9426 ("\reference to variable& not allowed"
9427 & " (RM 13.1(22))!", Nod, Ent);
9428 else
9429 Error_Msg_N
9430 ("non-static expression not allowed"
9431 & " (RM 13.1(22))!", Nod);
9432 end if;
9433 end if;
9434
9435 when N_Integer_Literal =>
9436
9437 -- If this is a rewritten unchecked conversion, in a system
9438 -- where Address is an integer type, always use the base type
9439 -- for a literal value. This is user-friendly and prevents
9440 -- order-of-elaboration issues with instances of unchecked
9441 -- conversion.
9442
9443 if Nkind (Original_Node (Nod)) = N_Function_Call then
9444 Set_Etype (Nod, Base_Type (Etype (Nod)));
9445 end if;
9446
9447 when N_Real_Literal |
9448 N_String_Literal |
9449 N_Character_Literal =>
9450 return;
9451
9452 when N_Range =>
9453 Check_Expr_Constants (Low_Bound (Nod));
9454 Check_Expr_Constants (High_Bound (Nod));
9455
9456 when N_Explicit_Dereference =>
9457 Check_Expr_Constants (Prefix (Nod));
9458
9459 when N_Indexed_Component =>
9460 Check_Expr_Constants (Prefix (Nod));
9461 Check_List_Constants (Expressions (Nod));
9462
9463 when N_Slice =>
9464 Check_Expr_Constants (Prefix (Nod));
9465 Check_Expr_Constants (Discrete_Range (Nod));
9466
9467 when N_Selected_Component =>
9468 Check_Expr_Constants (Prefix (Nod));
9469
9470 when N_Attribute_Reference =>
9471 if Nam_In (Attribute_Name (Nod), Name_Address,
9472 Name_Access,
9473 Name_Unchecked_Access,
9474 Name_Unrestricted_Access)
9475 then
9476 Check_At_Constant_Address (Prefix (Nod));
9477
9478 else
9479 Check_Expr_Constants (Prefix (Nod));
9480 Check_List_Constants (Expressions (Nod));
9481 end if;
9482
9483 when N_Aggregate =>
9484 Check_List_Constants (Component_Associations (Nod));
9485 Check_List_Constants (Expressions (Nod));
9486
9487 when N_Component_Association =>
9488 Check_Expr_Constants (Expression (Nod));
9489
9490 when N_Extension_Aggregate =>
9491 Check_Expr_Constants (Ancestor_Part (Nod));
9492 Check_List_Constants (Component_Associations (Nod));
9493 Check_List_Constants (Expressions (Nod));
9494
9495 when N_Null =>
9496 return;
9497
9498 when N_Binary_Op | N_Short_Circuit | N_Membership_Test =>
9499 Check_Expr_Constants (Left_Opnd (Nod));
9500 Check_Expr_Constants (Right_Opnd (Nod));
9501
9502 when N_Unary_Op =>
9503 Check_Expr_Constants (Right_Opnd (Nod));
9504
9505 when N_Type_Conversion |
9506 N_Qualified_Expression |
9507 N_Allocator |
9508 N_Unchecked_Type_Conversion =>
9509 Check_Expr_Constants (Expression (Nod));
9510
9511 when N_Function_Call =>
9512 if not Is_Pure (Entity (Name (Nod))) then
9513 Error_Msg_NE
9514 ("invalid address clause for initialized object &!",
9515 Nod, U_Ent);
9516
9517 Error_Msg_NE
9518 ("\function & is not pure (RM 13.1(22))!",
9519 Nod, Entity (Name (Nod)));
9520
9521 else
9522 Check_List_Constants (Parameter_Associations (Nod));
9523 end if;
9524
9525 when N_Parameter_Association =>
9526 Check_Expr_Constants (Explicit_Actual_Parameter (Nod));
9527
9528 when others =>
9529 Error_Msg_NE
9530 ("invalid address clause for initialized object &!",
9531 Nod, U_Ent);
9532 Error_Msg_NE
9533 ("\must be constant defined before& (RM 13.1(22))!",
9534 Nod, U_Ent);
9535 end case;
9536 end Check_Expr_Constants;
9537
9538 --------------------------
9539 -- Check_List_Constants --
9540 --------------------------
9541
9542 procedure Check_List_Constants (Lst : List_Id) is
9543 Nod1 : Node_Id;
9544
9545 begin
9546 if Present (Lst) then
9547 Nod1 := First (Lst);
9548 while Present (Nod1) loop
9549 Check_Expr_Constants (Nod1);
9550 Next (Nod1);
9551 end loop;
9552 end if;
9553 end Check_List_Constants;
9554
9555 -- Start of processing for Check_Constant_Address_Clause
9556
9557 begin
9558 -- If rep_clauses are to be ignored, no need for legality checks. In
9559 -- particular, no need to pester user about rep clauses that violate the
9560 -- rule on constant addresses, given that these clauses will be removed
9561 -- by Freeze before they reach the back end. Similarly in CodePeer mode,
9562 -- we want to relax these checks.
9563
9564 if not Ignore_Rep_Clauses and not CodePeer_Mode then
9565 Check_Expr_Constants (Expr);
9566 end if;
9567 end Check_Constant_Address_Clause;
9568
9569 ---------------------------
9570 -- Check_Pool_Size_Clash --
9571 ---------------------------
9572
9573 procedure Check_Pool_Size_Clash (Ent : Entity_Id; SP, SS : Node_Id) is
9574 Post : Node_Id;
9575
9576 begin
9577 -- We need to find out which one came first. Note that in the case of
9578 -- aspects mixed with pragmas there are cases where the processing order
9579 -- is reversed, which is why we do the check here.
9580
9581 if Sloc (SP) < Sloc (SS) then
9582 Error_Msg_Sloc := Sloc (SP);
9583 Post := SS;
9584 Error_Msg_NE ("Storage_Pool previously given for&#", Post, Ent);
9585
9586 else
9587 Error_Msg_Sloc := Sloc (SS);
9588 Post := SP;
9589 Error_Msg_NE ("Storage_Size previously given for&#", Post, Ent);
9590 end if;
9591
9592 Error_Msg_N
9593 ("\cannot have Storage_Size and Storage_Pool (RM 13.11(3))", Post);
9594 end Check_Pool_Size_Clash;
9595
9596 ----------------------------------------
9597 -- Check_Record_Representation_Clause --
9598 ----------------------------------------
9599
9600 procedure Check_Record_Representation_Clause (N : Node_Id) is
9601 Loc : constant Source_Ptr := Sloc (N);
9602 Ident : constant Node_Id := Identifier (N);
9603 Rectype : Entity_Id;
9604 Fent : Entity_Id;
9605 CC : Node_Id;
9606 Fbit : Uint;
9607 Lbit : Uint;
9608 Hbit : Uint := Uint_0;
9609 Comp : Entity_Id;
9610 Pcomp : Entity_Id;
9611
9612 Max_Bit_So_Far : Uint;
9613 -- Records the maximum bit position so far. If all field positions
9614 -- are monotonically increasing, then we can skip the circuit for
9615 -- checking for overlap, since no overlap is possible.
9616
9617 Tagged_Parent : Entity_Id := Empty;
9618 -- This is set in the case of a derived tagged type for which we have
9619 -- Is_Fully_Repped_Tagged_Type True (indicating that all components are
9620 -- positioned by record representation clauses). In this case we must
9621 -- check for overlap between components of this tagged type, and the
9622 -- components of its parent. Tagged_Parent will point to this parent
9623 -- type. For all other cases Tagged_Parent is left set to Empty.
9624
9625 Parent_Last_Bit : Uint;
9626 -- Relevant only if Tagged_Parent is set, Parent_Last_Bit indicates the
9627 -- last bit position for any field in the parent type. We only need to
9628 -- check overlap for fields starting below this point.
9629
9630 Overlap_Check_Required : Boolean;
9631 -- Used to keep track of whether or not an overlap check is required
9632
9633 Overlap_Detected : Boolean := False;
9634 -- Set True if an overlap is detected
9635
9636 Ccount : Natural := 0;
9637 -- Number of component clauses in record rep clause
9638
9639 procedure Check_Component_Overlap (C1_Ent, C2_Ent : Entity_Id);
9640 -- Given two entities for record components or discriminants, checks
9641 -- if they have overlapping component clauses and issues errors if so.
9642
9643 procedure Find_Component;
9644 -- Finds component entity corresponding to current component clause (in
9645 -- CC), and sets Comp to the entity, and Fbit/Lbit to the zero origin
9646 -- start/stop bits for the field. If there is no matching component or
9647 -- if the matching component does not have a component clause, then
9648 -- that's an error and Comp is set to Empty, but no error message is
9649 -- issued, since the message was already given. Comp is also set to
9650 -- Empty if the current "component clause" is in fact a pragma.
9651
9652 -----------------------------
9653 -- Check_Component_Overlap --
9654 -----------------------------
9655
9656 procedure Check_Component_Overlap (C1_Ent, C2_Ent : Entity_Id) is
9657 CC1 : constant Node_Id := Component_Clause (C1_Ent);
9658 CC2 : constant Node_Id := Component_Clause (C2_Ent);
9659
9660 begin
9661 if Present (CC1) and then Present (CC2) then
9662
9663 -- Exclude odd case where we have two tag components in the same
9664 -- record, both at location zero. This seems a bit strange, but
9665 -- it seems to happen in some circumstances, perhaps on an error.
9666
9667 if Nam_In (Chars (C1_Ent), Name_uTag, Name_uTag) then
9668 return;
9669 end if;
9670
9671 -- Here we check if the two fields overlap
9672
9673 declare
9674 S1 : constant Uint := Component_Bit_Offset (C1_Ent);
9675 S2 : constant Uint := Component_Bit_Offset (C2_Ent);
9676 E1 : constant Uint := S1 + Esize (C1_Ent);
9677 E2 : constant Uint := S2 + Esize (C2_Ent);
9678
9679 begin
9680 if E2 <= S1 or else E1 <= S2 then
9681 null;
9682 else
9683 Error_Msg_Node_2 := Component_Name (CC2);
9684 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
9685 Error_Msg_Node_1 := Component_Name (CC1);
9686 Error_Msg_N
9687 ("component& overlaps & #", Component_Name (CC1));
9688 Overlap_Detected := True;
9689 end if;
9690 end;
9691 end if;
9692 end Check_Component_Overlap;
9693
9694 --------------------
9695 -- Find_Component --
9696 --------------------
9697
9698 procedure Find_Component is
9699
9700 procedure Search_Component (R : Entity_Id);
9701 -- Search components of R for a match. If found, Comp is set
9702
9703 ----------------------
9704 -- Search_Component --
9705 ----------------------
9706
9707 procedure Search_Component (R : Entity_Id) is
9708 begin
9709 Comp := First_Component_Or_Discriminant (R);
9710 while Present (Comp) loop
9711
9712 -- Ignore error of attribute name for component name (we
9713 -- already gave an error message for this, so no need to
9714 -- complain here)
9715
9716 if Nkind (Component_Name (CC)) = N_Attribute_Reference then
9717 null;
9718 else
9719 exit when Chars (Comp) = Chars (Component_Name (CC));
9720 end if;
9721
9722 Next_Component_Or_Discriminant (Comp);
9723 end loop;
9724 end Search_Component;
9725
9726 -- Start of processing for Find_Component
9727
9728 begin
9729 -- Return with Comp set to Empty if we have a pragma
9730
9731 if Nkind (CC) = N_Pragma then
9732 Comp := Empty;
9733 return;
9734 end if;
9735
9736 -- Search current record for matching component
9737
9738 Search_Component (Rectype);
9739
9740 -- If not found, maybe component of base type discriminant that is
9741 -- absent from statically constrained first subtype.
9742
9743 if No (Comp) then
9744 Search_Component (Base_Type (Rectype));
9745 end if;
9746
9747 -- If no component, or the component does not reference the component
9748 -- clause in question, then there was some previous error for which
9749 -- we already gave a message, so just return with Comp Empty.
9750
9751 if No (Comp) or else Component_Clause (Comp) /= CC then
9752 Check_Error_Detected;
9753 Comp := Empty;
9754
9755 -- Normal case where we have a component clause
9756
9757 else
9758 Fbit := Component_Bit_Offset (Comp);
9759 Lbit := Fbit + Esize (Comp) - 1;
9760 end if;
9761 end Find_Component;
9762
9763 -- Start of processing for Check_Record_Representation_Clause
9764
9765 begin
9766 Find_Type (Ident);
9767 Rectype := Entity (Ident);
9768
9769 if Rectype = Any_Type then
9770 return;
9771 else
9772 Rectype := Underlying_Type (Rectype);
9773 end if;
9774
9775 -- See if we have a fully repped derived tagged type
9776
9777 declare
9778 PS : constant Entity_Id := Parent_Subtype (Rectype);
9779
9780 begin
9781 if Present (PS) and then Is_Fully_Repped_Tagged_Type (PS) then
9782 Tagged_Parent := PS;
9783
9784 -- Find maximum bit of any component of the parent type
9785
9786 Parent_Last_Bit := UI_From_Int (System_Address_Size - 1);
9787 Pcomp := First_Entity (Tagged_Parent);
9788 while Present (Pcomp) loop
9789 if Ekind_In (Pcomp, E_Discriminant, E_Component) then
9790 if Component_Bit_Offset (Pcomp) /= No_Uint
9791 and then Known_Static_Esize (Pcomp)
9792 then
9793 Parent_Last_Bit :=
9794 UI_Max
9795 (Parent_Last_Bit,
9796 Component_Bit_Offset (Pcomp) + Esize (Pcomp) - 1);
9797 end if;
9798 else
9799
9800 -- Skip anonymous types generated for constrained array
9801 -- or record components.
9802
9803 null;
9804 end if;
9805
9806 Next_Entity (Pcomp);
9807 end loop;
9808 end if;
9809 end;
9810
9811 -- All done if no component clauses
9812
9813 CC := First (Component_Clauses (N));
9814
9815 if No (CC) then
9816 return;
9817 end if;
9818
9819 -- If a tag is present, then create a component clause that places it
9820 -- at the start of the record (otherwise gigi may place it after other
9821 -- fields that have rep clauses).
9822
9823 Fent := First_Entity (Rectype);
9824
9825 if Nkind (Fent) = N_Defining_Identifier
9826 and then Chars (Fent) = Name_uTag
9827 then
9828 Set_Component_Bit_Offset (Fent, Uint_0);
9829 Set_Normalized_Position (Fent, Uint_0);
9830 Set_Normalized_First_Bit (Fent, Uint_0);
9831 Set_Normalized_Position_Max (Fent, Uint_0);
9832 Init_Esize (Fent, System_Address_Size);
9833
9834 Set_Component_Clause (Fent,
9835 Make_Component_Clause (Loc,
9836 Component_Name => Make_Identifier (Loc, Name_uTag),
9837
9838 Position => Make_Integer_Literal (Loc, Uint_0),
9839 First_Bit => Make_Integer_Literal (Loc, Uint_0),
9840 Last_Bit =>
9841 Make_Integer_Literal (Loc,
9842 UI_From_Int (System_Address_Size))));
9843
9844 Ccount := Ccount + 1;
9845 end if;
9846
9847 Max_Bit_So_Far := Uint_Minus_1;
9848 Overlap_Check_Required := False;
9849
9850 -- Process the component clauses
9851
9852 while Present (CC) loop
9853 Find_Component;
9854
9855 if Present (Comp) then
9856 Ccount := Ccount + 1;
9857
9858 -- We need a full overlap check if record positions non-monotonic
9859
9860 if Fbit <= Max_Bit_So_Far then
9861 Overlap_Check_Required := True;
9862 end if;
9863
9864 Max_Bit_So_Far := Lbit;
9865
9866 -- Check bit position out of range of specified size
9867
9868 if Has_Size_Clause (Rectype)
9869 and then RM_Size (Rectype) <= Lbit
9870 then
9871 Error_Msg_N
9872 ("bit number out of range of specified size",
9873 Last_Bit (CC));
9874
9875 -- Check for overlap with tag component
9876
9877 else
9878 if Is_Tagged_Type (Rectype)
9879 and then Fbit < System_Address_Size
9880 then
9881 Error_Msg_NE
9882 ("component overlaps tag field of&",
9883 Component_Name (CC), Rectype);
9884 Overlap_Detected := True;
9885 end if;
9886
9887 if Hbit < Lbit then
9888 Hbit := Lbit;
9889 end if;
9890 end if;
9891
9892 -- Check parent overlap if component might overlap parent field
9893
9894 if Present (Tagged_Parent) and then Fbit <= Parent_Last_Bit then
9895 Pcomp := First_Component_Or_Discriminant (Tagged_Parent);
9896 while Present (Pcomp) loop
9897 if not Is_Tag (Pcomp)
9898 and then Chars (Pcomp) /= Name_uParent
9899 then
9900 Check_Component_Overlap (Comp, Pcomp);
9901 end if;
9902
9903 Next_Component_Or_Discriminant (Pcomp);
9904 end loop;
9905 end if;
9906 end if;
9907
9908 Next (CC);
9909 end loop;
9910
9911 -- Now that we have processed all the component clauses, check for
9912 -- overlap. We have to leave this till last, since the components can
9913 -- appear in any arbitrary order in the representation clause.
9914
9915 -- We do not need this check if all specified ranges were monotonic,
9916 -- as recorded by Overlap_Check_Required being False at this stage.
9917
9918 -- This first section checks if there are any overlapping entries at
9919 -- all. It does this by sorting all entries and then seeing if there are
9920 -- any overlaps. If there are none, then that is decisive, but if there
9921 -- are overlaps, they may still be OK (they may result from fields in
9922 -- different variants).
9923
9924 if Overlap_Check_Required then
9925 Overlap_Check1 : declare
9926
9927 OC_Fbit : array (0 .. Ccount) of Uint;
9928 -- First-bit values for component clauses, the value is the offset
9929 -- of the first bit of the field from start of record. The zero
9930 -- entry is for use in sorting.
9931
9932 OC_Lbit : array (0 .. Ccount) of Uint;
9933 -- Last-bit values for component clauses, the value is the offset
9934 -- of the last bit of the field from start of record. The zero
9935 -- entry is for use in sorting.
9936
9937 OC_Count : Natural := 0;
9938 -- Count of entries in OC_Fbit and OC_Lbit
9939
9940 function OC_Lt (Op1, Op2 : Natural) return Boolean;
9941 -- Compare routine for Sort
9942
9943 procedure OC_Move (From : Natural; To : Natural);
9944 -- Move routine for Sort
9945
9946 package Sorting is new GNAT.Heap_Sort_G (OC_Move, OC_Lt);
9947
9948 -----------
9949 -- OC_Lt --
9950 -----------
9951
9952 function OC_Lt (Op1, Op2 : Natural) return Boolean is
9953 begin
9954 return OC_Fbit (Op1) < OC_Fbit (Op2);
9955 end OC_Lt;
9956
9957 -------------
9958 -- OC_Move --
9959 -------------
9960
9961 procedure OC_Move (From : Natural; To : Natural) is
9962 begin
9963 OC_Fbit (To) := OC_Fbit (From);
9964 OC_Lbit (To) := OC_Lbit (From);
9965 end OC_Move;
9966
9967 -- Start of processing for Overlap_Check
9968
9969 begin
9970 CC := First (Component_Clauses (N));
9971 while Present (CC) loop
9972
9973 -- Exclude component clause already marked in error
9974
9975 if not Error_Posted (CC) then
9976 Find_Component;
9977
9978 if Present (Comp) then
9979 OC_Count := OC_Count + 1;
9980 OC_Fbit (OC_Count) := Fbit;
9981 OC_Lbit (OC_Count) := Lbit;
9982 end if;
9983 end if;
9984
9985 Next (CC);
9986 end loop;
9987
9988 Sorting.Sort (OC_Count);
9989
9990 Overlap_Check_Required := False;
9991 for J in 1 .. OC_Count - 1 loop
9992 if OC_Lbit (J) >= OC_Fbit (J + 1) then
9993 Overlap_Check_Required := True;
9994 exit;
9995 end if;
9996 end loop;
9997 end Overlap_Check1;
9998 end if;
9999
10000 -- If Overlap_Check_Required is still True, then we have to do the full
10001 -- scale overlap check, since we have at least two fields that do
10002 -- overlap, and we need to know if that is OK since they are in
10003 -- different variant, or whether we have a definite problem.
10004
10005 if Overlap_Check_Required then
10006 Overlap_Check2 : declare
10007 C1_Ent, C2_Ent : Entity_Id;
10008 -- Entities of components being checked for overlap
10009
10010 Clist : Node_Id;
10011 -- Component_List node whose Component_Items are being checked
10012
10013 Citem : Node_Id;
10014 -- Component declaration for component being checked
10015
10016 begin
10017 C1_Ent := First_Entity (Base_Type (Rectype));
10018
10019 -- Loop through all components in record. For each component check
10020 -- for overlap with any of the preceding elements on the component
10021 -- list containing the component and also, if the component is in
10022 -- a variant, check against components outside the case structure.
10023 -- This latter test is repeated recursively up the variant tree.
10024
10025 Main_Component_Loop : while Present (C1_Ent) loop
10026 if not Ekind_In (C1_Ent, E_Component, E_Discriminant) then
10027 goto Continue_Main_Component_Loop;
10028 end if;
10029
10030 -- Skip overlap check if entity has no declaration node. This
10031 -- happens with discriminants in constrained derived types.
10032 -- Possibly we are missing some checks as a result, but that
10033 -- does not seem terribly serious.
10034
10035 if No (Declaration_Node (C1_Ent)) then
10036 goto Continue_Main_Component_Loop;
10037 end if;
10038
10039 Clist := Parent (List_Containing (Declaration_Node (C1_Ent)));
10040
10041 -- Loop through component lists that need checking. Check the
10042 -- current component list and all lists in variants above us.
10043
10044 Component_List_Loop : loop
10045
10046 -- If derived type definition, go to full declaration
10047 -- If at outer level, check discriminants if there are any.
10048
10049 if Nkind (Clist) = N_Derived_Type_Definition then
10050 Clist := Parent (Clist);
10051 end if;
10052
10053 -- Outer level of record definition, check discriminants
10054
10055 if Nkind_In (Clist, N_Full_Type_Declaration,
10056 N_Private_Type_Declaration)
10057 then
10058 if Has_Discriminants (Defining_Identifier (Clist)) then
10059 C2_Ent :=
10060 First_Discriminant (Defining_Identifier (Clist));
10061 while Present (C2_Ent) loop
10062 exit when C1_Ent = C2_Ent;
10063 Check_Component_Overlap (C1_Ent, C2_Ent);
10064 Next_Discriminant (C2_Ent);
10065 end loop;
10066 end if;
10067
10068 -- Record extension case
10069
10070 elsif Nkind (Clist) = N_Derived_Type_Definition then
10071 Clist := Empty;
10072
10073 -- Otherwise check one component list
10074
10075 else
10076 Citem := First (Component_Items (Clist));
10077 while Present (Citem) loop
10078 if Nkind (Citem) = N_Component_Declaration then
10079 C2_Ent := Defining_Identifier (Citem);
10080 exit when C1_Ent = C2_Ent;
10081 Check_Component_Overlap (C1_Ent, C2_Ent);
10082 end if;
10083
10084 Next (Citem);
10085 end loop;
10086 end if;
10087
10088 -- Check for variants above us (the parent of the Clist can
10089 -- be a variant, in which case its parent is a variant part,
10090 -- and the parent of the variant part is a component list
10091 -- whose components must all be checked against the current
10092 -- component for overlap).
10093
10094 if Nkind (Parent (Clist)) = N_Variant then
10095 Clist := Parent (Parent (Parent (Clist)));
10096
10097 -- Check for possible discriminant part in record, this
10098 -- is treated essentially as another level in the
10099 -- recursion. For this case the parent of the component
10100 -- list is the record definition, and its parent is the
10101 -- full type declaration containing the discriminant
10102 -- specifications.
10103
10104 elsif Nkind (Parent (Clist)) = N_Record_Definition then
10105 Clist := Parent (Parent ((Clist)));
10106
10107 -- If neither of these two cases, we are at the top of
10108 -- the tree.
10109
10110 else
10111 exit Component_List_Loop;
10112 end if;
10113 end loop Component_List_Loop;
10114
10115 <<Continue_Main_Component_Loop>>
10116 Next_Entity (C1_Ent);
10117
10118 end loop Main_Component_Loop;
10119 end Overlap_Check2;
10120 end if;
10121
10122 -- The following circuit deals with warning on record holes (gaps). We
10123 -- skip this check if overlap was detected, since it makes sense for the
10124 -- programmer to fix this illegality before worrying about warnings.
10125
10126 if not Overlap_Detected and Warn_On_Record_Holes then
10127 Record_Hole_Check : declare
10128 Decl : constant Node_Id := Declaration_Node (Base_Type (Rectype));
10129 -- Full declaration of record type
10130
10131 procedure Check_Component_List
10132 (CL : Node_Id;
10133 Sbit : Uint;
10134 DS : List_Id);
10135 -- Check component list CL for holes. The starting bit should be
10136 -- Sbit. which is zero for the main record component list and set
10137 -- appropriately for recursive calls for variants. DS is set to
10138 -- a list of discriminant specifications to be included in the
10139 -- consideration of components. It is No_List if none to consider.
10140
10141 --------------------------
10142 -- Check_Component_List --
10143 --------------------------
10144
10145 procedure Check_Component_List
10146 (CL : Node_Id;
10147 Sbit : Uint;
10148 DS : List_Id)
10149 is
10150 Compl : Integer;
10151
10152 begin
10153 Compl := Integer (List_Length (Component_Items (CL)));
10154
10155 if DS /= No_List then
10156 Compl := Compl + Integer (List_Length (DS));
10157 end if;
10158
10159 declare
10160 Comps : array (Natural range 0 .. Compl) of Entity_Id;
10161 -- Gather components (zero entry is for sort routine)
10162
10163 Ncomps : Natural := 0;
10164 -- Number of entries stored in Comps (starting at Comps (1))
10165
10166 Citem : Node_Id;
10167 -- One component item or discriminant specification
10168
10169 Nbit : Uint;
10170 -- Starting bit for next component
10171
10172 CEnt : Entity_Id;
10173 -- Component entity
10174
10175 Variant : Node_Id;
10176 -- One variant
10177
10178 function Lt (Op1, Op2 : Natural) return Boolean;
10179 -- Compare routine for Sort
10180
10181 procedure Move (From : Natural; To : Natural);
10182 -- Move routine for Sort
10183
10184 package Sorting is new GNAT.Heap_Sort_G (Move, Lt);
10185
10186 --------
10187 -- Lt --
10188 --------
10189
10190 function Lt (Op1, Op2 : Natural) return Boolean is
10191 begin
10192 return Component_Bit_Offset (Comps (Op1))
10193 <
10194 Component_Bit_Offset (Comps (Op2));
10195 end Lt;
10196
10197 ----------
10198 -- Move --
10199 ----------
10200
10201 procedure Move (From : Natural; To : Natural) is
10202 begin
10203 Comps (To) := Comps (From);
10204 end Move;
10205
10206 begin
10207 -- Gather discriminants into Comp
10208
10209 if DS /= No_List then
10210 Citem := First (DS);
10211 while Present (Citem) loop
10212 if Nkind (Citem) = N_Discriminant_Specification then
10213 declare
10214 Ent : constant Entity_Id :=
10215 Defining_Identifier (Citem);
10216 begin
10217 if Ekind (Ent) = E_Discriminant then
10218 Ncomps := Ncomps + 1;
10219 Comps (Ncomps) := Ent;
10220 end if;
10221 end;
10222 end if;
10223
10224 Next (Citem);
10225 end loop;
10226 end if;
10227
10228 -- Gather component entities into Comp
10229
10230 Citem := First (Component_Items (CL));
10231 while Present (Citem) loop
10232 if Nkind (Citem) = N_Component_Declaration then
10233 Ncomps := Ncomps + 1;
10234 Comps (Ncomps) := Defining_Identifier (Citem);
10235 end if;
10236
10237 Next (Citem);
10238 end loop;
10239
10240 -- Now sort the component entities based on the first bit.
10241 -- Note we already know there are no overlapping components.
10242
10243 Sorting.Sort (Ncomps);
10244
10245 -- Loop through entries checking for holes
10246
10247 Nbit := Sbit;
10248 for J in 1 .. Ncomps loop
10249 CEnt := Comps (J);
10250 Error_Msg_Uint_1 := Component_Bit_Offset (CEnt) - Nbit;
10251
10252 if Error_Msg_Uint_1 > 0 then
10253 Error_Msg_NE
10254 ("?H?^-bit gap before component&",
10255 Component_Name (Component_Clause (CEnt)), CEnt);
10256 end if;
10257
10258 Nbit := Component_Bit_Offset (CEnt) + Esize (CEnt);
10259 end loop;
10260
10261 -- Process variant parts recursively if present
10262
10263 if Present (Variant_Part (CL)) then
10264 Variant := First (Variants (Variant_Part (CL)));
10265 while Present (Variant) loop
10266 Check_Component_List
10267 (Component_List (Variant), Nbit, No_List);
10268 Next (Variant);
10269 end loop;
10270 end if;
10271 end;
10272 end Check_Component_List;
10273
10274 -- Start of processing for Record_Hole_Check
10275
10276 begin
10277 declare
10278 Sbit : Uint;
10279
10280 begin
10281 if Is_Tagged_Type (Rectype) then
10282 Sbit := UI_From_Int (System_Address_Size);
10283 else
10284 Sbit := Uint_0;
10285 end if;
10286
10287 if Nkind (Decl) = N_Full_Type_Declaration
10288 and then Nkind (Type_Definition (Decl)) = N_Record_Definition
10289 then
10290 Check_Component_List
10291 (Component_List (Type_Definition (Decl)),
10292 Sbit,
10293 Discriminant_Specifications (Decl));
10294 end if;
10295 end;
10296 end Record_Hole_Check;
10297 end if;
10298
10299 -- For records that have component clauses for all components, and whose
10300 -- size is less than or equal to 32, we need to know the size in the
10301 -- front end to activate possible packed array processing where the
10302 -- component type is a record.
10303
10304 -- At this stage Hbit + 1 represents the first unused bit from all the
10305 -- component clauses processed, so if the component clauses are
10306 -- complete, then this is the length of the record.
10307
10308 -- For records longer than System.Storage_Unit, and for those where not
10309 -- all components have component clauses, the back end determines the
10310 -- length (it may for example be appropriate to round up the size
10311 -- to some convenient boundary, based on alignment considerations, etc).
10312
10313 if Unknown_RM_Size (Rectype) and then Hbit + 1 <= 32 then
10314
10315 -- Nothing to do if at least one component has no component clause
10316
10317 Comp := First_Component_Or_Discriminant (Rectype);
10318 while Present (Comp) loop
10319 exit when No (Component_Clause (Comp));
10320 Next_Component_Or_Discriminant (Comp);
10321 end loop;
10322
10323 -- If we fall out of loop, all components have component clauses
10324 -- and so we can set the size to the maximum value.
10325
10326 if No (Comp) then
10327 Set_RM_Size (Rectype, Hbit + 1);
10328 end if;
10329 end if;
10330 end Check_Record_Representation_Clause;
10331
10332 ----------------
10333 -- Check_Size --
10334 ----------------
10335
10336 procedure Check_Size
10337 (N : Node_Id;
10338 T : Entity_Id;
10339 Siz : Uint;
10340 Biased : out Boolean)
10341 is
10342 procedure Size_Too_Small_Error (Min_Siz : Uint);
10343 -- Emit an error concerning illegal size Siz. Min_Siz denotes the
10344 -- minimum size.
10345
10346 --------------------------
10347 -- Size_Too_Small_Error --
10348 --------------------------
10349
10350 procedure Size_Too_Small_Error (Min_Siz : Uint) is
10351 begin
10352 -- This error is suppressed in ASIS mode to allow for different ASIS
10353 -- back ends or ASIS-based tools to query the illegal clause.
10354
10355 if not ASIS_Mode then
10356 Error_Msg_Uint_1 := Min_Siz;
10357 Error_Msg_NE ("size for& too small, minimum allowed is ^", N, T);
10358 end if;
10359 end Size_Too_Small_Error;
10360
10361 -- Local variables
10362
10363 UT : constant Entity_Id := Underlying_Type (T);
10364 M : Uint;
10365
10366 -- Start of processing for Check_Size
10367
10368 begin
10369 Biased := False;
10370
10371 -- Reject patently improper size values
10372
10373 if Is_Elementary_Type (T)
10374 and then Siz > UI_From_Int (Int'Last)
10375 then
10376 Error_Msg_N ("Size value too large for elementary type", N);
10377
10378 if Nkind (Original_Node (N)) = N_Op_Expon then
10379 Error_Msg_N
10380 ("\maybe '* was meant, rather than '*'*", Original_Node (N));
10381 end if;
10382 end if;
10383
10384 -- Dismiss generic types
10385
10386 if Is_Generic_Type (T)
10387 or else
10388 Is_Generic_Type (UT)
10389 or else
10390 Is_Generic_Type (Root_Type (UT))
10391 then
10392 return;
10393
10394 -- Guard against previous errors
10395
10396 elsif No (UT) or else UT = Any_Type then
10397 Check_Error_Detected;
10398 return;
10399
10400 -- Check case of bit packed array
10401
10402 elsif Is_Array_Type (UT)
10403 and then Known_Static_Component_Size (UT)
10404 and then Is_Bit_Packed_Array (UT)
10405 then
10406 declare
10407 Asiz : Uint;
10408 Indx : Node_Id;
10409 Ityp : Entity_Id;
10410
10411 begin
10412 Asiz := Component_Size (UT);
10413 Indx := First_Index (UT);
10414 loop
10415 Ityp := Etype (Indx);
10416
10417 -- If non-static bound, then we are not in the business of
10418 -- trying to check the length, and indeed an error will be
10419 -- issued elsewhere, since sizes of non-static array types
10420 -- cannot be set implicitly or explicitly.
10421
10422 if not Is_OK_Static_Subtype (Ityp) then
10423 return;
10424 end if;
10425
10426 -- Otherwise accumulate next dimension
10427
10428 Asiz := Asiz * (Expr_Value (Type_High_Bound (Ityp)) -
10429 Expr_Value (Type_Low_Bound (Ityp)) +
10430 Uint_1);
10431
10432 Next_Index (Indx);
10433 exit when No (Indx);
10434 end loop;
10435
10436 if Asiz <= Siz then
10437 return;
10438
10439 else
10440 Size_Too_Small_Error (Asiz);
10441 Set_Esize (T, Asiz);
10442 Set_RM_Size (T, Asiz);
10443 end if;
10444 end;
10445
10446 -- All other composite types are ignored
10447
10448 elsif Is_Composite_Type (UT) then
10449 return;
10450
10451 -- For fixed-point types, don't check minimum if type is not frozen,
10452 -- since we don't know all the characteristics of the type that can
10453 -- affect the size (e.g. a specified small) till freeze time.
10454
10455 elsif Is_Fixed_Point_Type (UT) and then not Is_Frozen (UT) then
10456 null;
10457
10458 -- Cases for which a minimum check is required
10459
10460 else
10461 -- Ignore if specified size is correct for the type
10462
10463 if Known_Esize (UT) and then Siz = Esize (UT) then
10464 return;
10465 end if;
10466
10467 -- Otherwise get minimum size
10468
10469 M := UI_From_Int (Minimum_Size (UT));
10470
10471 if Siz < M then
10472
10473 -- Size is less than minimum size, but one possibility remains
10474 -- that we can manage with the new size if we bias the type.
10475
10476 M := UI_From_Int (Minimum_Size (UT, Biased => True));
10477
10478 if Siz < M then
10479 Size_Too_Small_Error (M);
10480 Set_Esize (T, M);
10481 Set_RM_Size (T, M);
10482 else
10483 Biased := True;
10484 end if;
10485 end if;
10486 end if;
10487 end Check_Size;
10488
10489 --------------------------
10490 -- Freeze_Entity_Checks --
10491 --------------------------
10492
10493 procedure Freeze_Entity_Checks (N : Node_Id) is
10494 procedure Hide_Non_Overridden_Subprograms (Typ : Entity_Id);
10495 -- Inspect the primitive operations of type Typ and hide all pairs of
10496 -- implicitly declared non-overridden non-fully conformant homographs
10497 -- (Ada RM 8.3 12.3/2).
10498
10499 -------------------------------------
10500 -- Hide_Non_Overridden_Subprograms --
10501 -------------------------------------
10502
10503 procedure Hide_Non_Overridden_Subprograms (Typ : Entity_Id) is
10504 procedure Hide_Matching_Homographs
10505 (Subp_Id : Entity_Id;
10506 Start_Elmt : Elmt_Id);
10507 -- Inspect a list of primitive operations starting with Start_Elmt
10508 -- and find matching implicitly declared non-overridden non-fully
10509 -- conformant homographs of Subp_Id. If found, all matches along
10510 -- with Subp_Id are hidden from all visibility.
10511
10512 function Is_Non_Overridden_Or_Null_Procedure
10513 (Subp_Id : Entity_Id) return Boolean;
10514 -- Determine whether subprogram Subp_Id is implicitly declared non-
10515 -- overridden subprogram or an implicitly declared null procedure.
10516
10517 ------------------------------
10518 -- Hide_Matching_Homographs --
10519 ------------------------------
10520
10521 procedure Hide_Matching_Homographs
10522 (Subp_Id : Entity_Id;
10523 Start_Elmt : Elmt_Id)
10524 is
10525 Prim : Entity_Id;
10526 Prim_Elmt : Elmt_Id;
10527
10528 begin
10529 Prim_Elmt := Start_Elmt;
10530 while Present (Prim_Elmt) loop
10531 Prim := Node (Prim_Elmt);
10532
10533 -- The current primitive is implicitly declared non-overridden
10534 -- non-fully conformant homograph of Subp_Id. Both subprograms
10535 -- must be hidden from visibility.
10536
10537 if Chars (Prim) = Chars (Subp_Id)
10538 and then Is_Non_Overridden_Or_Null_Procedure (Prim)
10539 and then not Fully_Conformant (Prim, Subp_Id)
10540 then
10541 Set_Is_Hidden_Non_Overridden_Subpgm (Prim);
10542 Set_Is_Immediately_Visible (Prim, False);
10543 Set_Is_Potentially_Use_Visible (Prim, False);
10544
10545 Set_Is_Hidden_Non_Overridden_Subpgm (Subp_Id);
10546 Set_Is_Immediately_Visible (Subp_Id, False);
10547 Set_Is_Potentially_Use_Visible (Subp_Id, False);
10548 end if;
10549
10550 Next_Elmt (Prim_Elmt);
10551 end loop;
10552 end Hide_Matching_Homographs;
10553
10554 -----------------------------------------
10555 -- Is_Non_Overridden_Or_Null_Procedure --
10556 -----------------------------------------
10557
10558 function Is_Non_Overridden_Or_Null_Procedure
10559 (Subp_Id : Entity_Id) return Boolean
10560 is
10561 Alias_Id : Entity_Id;
10562
10563 begin
10564 -- The subprogram is inherited (implicitly declared), it does not
10565 -- override and does not cover a primitive of an interface.
10566
10567 if Ekind_In (Subp_Id, E_Function, E_Procedure)
10568 and then Present (Alias (Subp_Id))
10569 and then No (Interface_Alias (Subp_Id))
10570 and then No (Overridden_Operation (Subp_Id))
10571 then
10572 Alias_Id := Alias (Subp_Id);
10573
10574 if Requires_Overriding (Alias_Id) then
10575 return True;
10576
10577 elsif Nkind (Parent (Alias_Id)) = N_Procedure_Specification
10578 and then Null_Present (Parent (Alias_Id))
10579 then
10580 return True;
10581 end if;
10582 end if;
10583
10584 return False;
10585 end Is_Non_Overridden_Or_Null_Procedure;
10586
10587 -- Local variables
10588
10589 Prim_Ops : constant Elist_Id := Direct_Primitive_Operations (Typ);
10590 Prim : Entity_Id;
10591 Prim_Elmt : Elmt_Id;
10592
10593 -- Start of processing for Hide_Non_Overridden_Subprograms
10594
10595 begin
10596 -- Inspect the list of primitives looking for non-overridden
10597 -- subprograms.
10598
10599 if Present (Prim_Ops) then
10600 Prim_Elmt := First_Elmt (Prim_Ops);
10601 while Present (Prim_Elmt) loop
10602 Prim := Node (Prim_Elmt);
10603 Next_Elmt (Prim_Elmt);
10604
10605 if Is_Non_Overridden_Or_Null_Procedure (Prim) then
10606 Hide_Matching_Homographs
10607 (Subp_Id => Prim,
10608 Start_Elmt => Prim_Elmt);
10609 end if;
10610 end loop;
10611 end if;
10612 end Hide_Non_Overridden_Subprograms;
10613
10614 -- Local variables
10615
10616 E : constant Entity_Id := Entity (N);
10617
10618 Non_Generic_Case : constant Boolean := Nkind (N) = N_Freeze_Entity;
10619 -- True in non-generic case. Some of the processing here is skipped
10620 -- for the generic case since it is not needed. Basically in the
10621 -- generic case, we only need to do stuff that might generate error
10622 -- messages or warnings.
10623
10624 -- Start of processing for Freeze_Entity_Checks
10625
10626 begin
10627 -- Remember that we are processing a freezing entity. Required to
10628 -- ensure correct decoration of internal entities associated with
10629 -- interfaces (see New_Overloaded_Entity).
10630
10631 Inside_Freezing_Actions := Inside_Freezing_Actions + 1;
10632
10633 -- For tagged types covering interfaces add internal entities that link
10634 -- the primitives of the interfaces with the primitives that cover them.
10635 -- Note: These entities were originally generated only when generating
10636 -- code because their main purpose was to provide support to initialize
10637 -- the secondary dispatch tables. They are now generated also when
10638 -- compiling with no code generation to provide ASIS the relationship
10639 -- between interface primitives and tagged type primitives. They are
10640 -- also used to locate primitives covering interfaces when processing
10641 -- generics (see Derive_Subprograms).
10642
10643 -- This is not needed in the generic case
10644
10645 if Ada_Version >= Ada_2005
10646 and then Non_Generic_Case
10647 and then Ekind (E) = E_Record_Type
10648 and then Is_Tagged_Type (E)
10649 and then not Is_Interface (E)
10650 and then Has_Interfaces (E)
10651 then
10652 -- This would be a good common place to call the routine that checks
10653 -- overriding of interface primitives (and thus factorize calls to
10654 -- Check_Abstract_Overriding located at different contexts in the
10655 -- compiler). However, this is not possible because it causes
10656 -- spurious errors in case of late overriding.
10657
10658 Add_Internal_Interface_Entities (E);
10659 end if;
10660
10661 -- After all forms of overriding have been resolved, a tagged type may
10662 -- be left with a set of implicitly declared and possibly erroneous
10663 -- abstract subprograms, null procedures and subprograms that require
10664 -- overriding. If this set contains fully conformant homographs, then
10665 -- one is chosen arbitrarily (already done during resolution), otherwise
10666 -- all remaining non-fully conformant homographs are hidden from
10667 -- visibility (Ada RM 8.3 12.3/2).
10668
10669 if Is_Tagged_Type (E) then
10670 Hide_Non_Overridden_Subprograms (E);
10671 end if;
10672
10673 -- Check CPP types
10674
10675 if Ekind (E) = E_Record_Type
10676 and then Is_CPP_Class (E)
10677 and then Is_Tagged_Type (E)
10678 and then Tagged_Type_Expansion
10679 then
10680 if CPP_Num_Prims (E) = 0 then
10681
10682 -- If the CPP type has user defined components then it must import
10683 -- primitives from C++. This is required because if the C++ class
10684 -- has no primitives then the C++ compiler does not added the _tag
10685 -- component to the type.
10686
10687 if First_Entity (E) /= Last_Entity (E) then
10688 Error_Msg_N
10689 ("'C'P'P type must import at least one primitive from C++??",
10690 E);
10691 end if;
10692 end if;
10693
10694 -- Check that all its primitives are abstract or imported from C++.
10695 -- Check also availability of the C++ constructor.
10696
10697 declare
10698 Has_Constructors : constant Boolean := Has_CPP_Constructors (E);
10699 Elmt : Elmt_Id;
10700 Error_Reported : Boolean := False;
10701 Prim : Node_Id;
10702
10703 begin
10704 Elmt := First_Elmt (Primitive_Operations (E));
10705 while Present (Elmt) loop
10706 Prim := Node (Elmt);
10707
10708 if Comes_From_Source (Prim) then
10709 if Is_Abstract_Subprogram (Prim) then
10710 null;
10711
10712 elsif not Is_Imported (Prim)
10713 or else Convention (Prim) /= Convention_CPP
10714 then
10715 Error_Msg_N
10716 ("primitives of 'C'P'P types must be imported from C++ "
10717 & "or abstract??", Prim);
10718
10719 elsif not Has_Constructors
10720 and then not Error_Reported
10721 then
10722 Error_Msg_Name_1 := Chars (E);
10723 Error_Msg_N
10724 ("??'C'P'P constructor required for type %", Prim);
10725 Error_Reported := True;
10726 end if;
10727 end if;
10728
10729 Next_Elmt (Elmt);
10730 end loop;
10731 end;
10732 end if;
10733
10734 -- Check Ada derivation of CPP type
10735
10736 if Expander_Active -- why? losing errors in -gnatc mode???
10737 and then Present (Etype (E)) -- defend against errors
10738 and then Tagged_Type_Expansion
10739 and then Ekind (E) = E_Record_Type
10740 and then Etype (E) /= E
10741 and then Is_CPP_Class (Etype (E))
10742 and then CPP_Num_Prims (Etype (E)) > 0
10743 and then not Is_CPP_Class (E)
10744 and then not Has_CPP_Constructors (Etype (E))
10745 then
10746 -- If the parent has C++ primitives but it has no constructor then
10747 -- check that all the primitives are overridden in this derivation;
10748 -- otherwise the constructor of the parent is needed to build the
10749 -- dispatch table.
10750
10751 declare
10752 Elmt : Elmt_Id;
10753 Prim : Node_Id;
10754
10755 begin
10756 Elmt := First_Elmt (Primitive_Operations (E));
10757 while Present (Elmt) loop
10758 Prim := Node (Elmt);
10759
10760 if not Is_Abstract_Subprogram (Prim)
10761 and then No (Interface_Alias (Prim))
10762 and then Find_Dispatching_Type (Ultimate_Alias (Prim)) /= E
10763 then
10764 Error_Msg_Name_1 := Chars (Etype (E));
10765 Error_Msg_N
10766 ("'C'P'P constructor required for parent type %", E);
10767 exit;
10768 end if;
10769
10770 Next_Elmt (Elmt);
10771 end loop;
10772 end;
10773 end if;
10774
10775 Inside_Freezing_Actions := Inside_Freezing_Actions - 1;
10776
10777 -- If we have a type with predicates, build predicate function. This is
10778 -- not needed in the generic case, nor within TSS subprograms and other
10779 -- predefined primitives.
10780
10781 if Is_Type (E)
10782 and then Non_Generic_Case
10783 and then not Within_Internal_Subprogram
10784 and then Has_Predicates (E)
10785 then
10786 Build_Predicate_Functions (E, N);
10787 end if;
10788
10789 -- If type has delayed aspects, this is where we do the preanalysis at
10790 -- the freeze point, as part of the consistent visibility check. Note
10791 -- that this must be done after calling Build_Predicate_Functions or
10792 -- Build_Invariant_Procedure since these subprograms fix occurrences of
10793 -- the subtype name in the saved expression so that they will not cause
10794 -- trouble in the preanalysis.
10795
10796 -- This is also not needed in the generic case
10797
10798 if Non_Generic_Case
10799 and then Has_Delayed_Aspects (E)
10800 and then Scope (E) = Current_Scope
10801 then
10802 -- Retrieve the visibility to the discriminants in order to properly
10803 -- analyze the aspects.
10804
10805 Push_Scope_And_Install_Discriminants (E);
10806
10807 declare
10808 Ritem : Node_Id;
10809
10810 begin
10811 -- Look for aspect specification entries for this entity
10812
10813 Ritem := First_Rep_Item (E);
10814 while Present (Ritem) loop
10815 if Nkind (Ritem) = N_Aspect_Specification
10816 and then Entity (Ritem) = E
10817 and then Is_Delayed_Aspect (Ritem)
10818 then
10819 Check_Aspect_At_Freeze_Point (Ritem);
10820 end if;
10821
10822 Next_Rep_Item (Ritem);
10823 end loop;
10824 end;
10825
10826 Uninstall_Discriminants_And_Pop_Scope (E);
10827 end if;
10828
10829 -- For a record type, deal with variant parts. This has to be delayed
10830 -- to this point, because of the issue of statically predicated
10831 -- subtypes, which we have to ensure are frozen before checking
10832 -- choices, since we need to have the static choice list set.
10833
10834 if Is_Record_Type (E) then
10835 Check_Variant_Part : declare
10836 D : constant Node_Id := Declaration_Node (E);
10837 T : Node_Id;
10838 C : Node_Id;
10839 VP : Node_Id;
10840
10841 Others_Present : Boolean;
10842 pragma Warnings (Off, Others_Present);
10843 -- Indicates others present, not used in this case
10844
10845 procedure Non_Static_Choice_Error (Choice : Node_Id);
10846 -- Error routine invoked by the generic instantiation below when
10847 -- the variant part has a non static choice.
10848
10849 procedure Process_Declarations (Variant : Node_Id);
10850 -- Processes declarations associated with a variant. We analyzed
10851 -- the declarations earlier (in Sem_Ch3.Analyze_Variant_Part),
10852 -- but we still need the recursive call to Check_Choices for any
10853 -- nested variant to get its choices properly processed. This is
10854 -- also where we expand out the choices if expansion is active.
10855
10856 package Variant_Choices_Processing is new
10857 Generic_Check_Choices
10858 (Process_Empty_Choice => No_OP,
10859 Process_Non_Static_Choice => Non_Static_Choice_Error,
10860 Process_Associated_Node => Process_Declarations);
10861 use Variant_Choices_Processing;
10862
10863 -----------------------------
10864 -- Non_Static_Choice_Error --
10865 -----------------------------
10866
10867 procedure Non_Static_Choice_Error (Choice : Node_Id) is
10868 begin
10869 Flag_Non_Static_Expr
10870 ("choice given in variant part is not static!", Choice);
10871 end Non_Static_Choice_Error;
10872
10873 --------------------------
10874 -- Process_Declarations --
10875 --------------------------
10876
10877 procedure Process_Declarations (Variant : Node_Id) is
10878 CL : constant Node_Id := Component_List (Variant);
10879 VP : Node_Id;
10880
10881 begin
10882 -- Check for static predicate present in this variant
10883
10884 if Has_SP_Choice (Variant) then
10885
10886 -- Here we expand. You might expect to find this call in
10887 -- Expand_N_Variant_Part, but that is called when we first
10888 -- see the variant part, and we cannot do this expansion
10889 -- earlier than the freeze point, since for statically
10890 -- predicated subtypes, the predicate is not known till
10891 -- the freeze point.
10892
10893 -- Furthermore, we do this expansion even if the expander
10894 -- is not active, because other semantic processing, e.g.
10895 -- for aggregates, requires the expanded list of choices.
10896
10897 -- If the expander is not active, then we can't just clobber
10898 -- the list since it would invalidate the ASIS -gnatct tree.
10899 -- So we have to rewrite the variant part with a Rewrite
10900 -- call that replaces it with a copy and clobber the copy.
10901
10902 if not Expander_Active then
10903 declare
10904 NewV : constant Node_Id := New_Copy (Variant);
10905 begin
10906 Set_Discrete_Choices
10907 (NewV, New_Copy_List (Discrete_Choices (Variant)));
10908 Rewrite (Variant, NewV);
10909 end;
10910 end if;
10911
10912 Expand_Static_Predicates_In_Choices (Variant);
10913 end if;
10914
10915 -- We don't need to worry about the declarations in the variant
10916 -- (since they were analyzed by Analyze_Choices when we first
10917 -- encountered the variant), but we do need to take care of
10918 -- expansion of any nested variants.
10919
10920 if not Null_Present (CL) then
10921 VP := Variant_Part (CL);
10922
10923 if Present (VP) then
10924 Check_Choices
10925 (VP, Variants (VP), Etype (Name (VP)), Others_Present);
10926 end if;
10927 end if;
10928 end Process_Declarations;
10929
10930 -- Start of processing for Check_Variant_Part
10931
10932 begin
10933 -- Find component list
10934
10935 C := Empty;
10936
10937 if Nkind (D) = N_Full_Type_Declaration then
10938 T := Type_Definition (D);
10939
10940 if Nkind (T) = N_Record_Definition then
10941 C := Component_List (T);
10942
10943 elsif Nkind (T) = N_Derived_Type_Definition
10944 and then Present (Record_Extension_Part (T))
10945 then
10946 C := Component_List (Record_Extension_Part (T));
10947 end if;
10948 end if;
10949
10950 -- Case of variant part present
10951
10952 if Present (C) and then Present (Variant_Part (C)) then
10953 VP := Variant_Part (C);
10954
10955 -- Check choices
10956
10957 Check_Choices
10958 (VP, Variants (VP), Etype (Name (VP)), Others_Present);
10959
10960 -- If the last variant does not contain the Others choice,
10961 -- replace it with an N_Others_Choice node since Gigi always
10962 -- wants an Others. Note that we do not bother to call Analyze
10963 -- on the modified variant part, since its only effect would be
10964 -- to compute the Others_Discrete_Choices node laboriously, and
10965 -- of course we already know the list of choices corresponding
10966 -- to the others choice (it's the list we're replacing).
10967
10968 -- We only want to do this if the expander is active, since
10969 -- we do not want to clobber the ASIS tree.
10970
10971 if Expander_Active then
10972 declare
10973 Last_Var : constant Node_Id :=
10974 Last_Non_Pragma (Variants (VP));
10975
10976 Others_Node : Node_Id;
10977
10978 begin
10979 if Nkind (First (Discrete_Choices (Last_Var))) /=
10980 N_Others_Choice
10981 then
10982 Others_Node := Make_Others_Choice (Sloc (Last_Var));
10983 Set_Others_Discrete_Choices
10984 (Others_Node, Discrete_Choices (Last_Var));
10985 Set_Discrete_Choices
10986 (Last_Var, New_List (Others_Node));
10987 end if;
10988 end;
10989 end if;
10990 end if;
10991 end Check_Variant_Part;
10992 end if;
10993 end Freeze_Entity_Checks;
10994
10995 -------------------------
10996 -- Get_Alignment_Value --
10997 -------------------------
10998
10999 function Get_Alignment_Value (Expr : Node_Id) return Uint is
11000 Align : constant Uint := Static_Integer (Expr);
11001
11002 begin
11003 if Align = No_Uint then
11004 return No_Uint;
11005
11006 elsif Align <= 0 then
11007
11008 -- This error is suppressed in ASIS mode to allow for different ASIS
11009 -- back ends or ASIS-based tools to query the illegal clause.
11010
11011 if not ASIS_Mode then
11012 Error_Msg_N ("alignment value must be positive", Expr);
11013 end if;
11014
11015 return No_Uint;
11016
11017 else
11018 for J in Int range 0 .. 64 loop
11019 declare
11020 M : constant Uint := Uint_2 ** J;
11021
11022 begin
11023 exit when M = Align;
11024
11025 if M > Align then
11026
11027 -- This error is suppressed in ASIS mode to allow for
11028 -- different ASIS back ends or ASIS-based tools to query the
11029 -- illegal clause.
11030
11031 if not ASIS_Mode then
11032 Error_Msg_N ("alignment value must be power of 2", Expr);
11033 end if;
11034
11035 return No_Uint;
11036 end if;
11037 end;
11038 end loop;
11039
11040 return Align;
11041 end if;
11042 end Get_Alignment_Value;
11043
11044 -----------------------------
11045 -- Get_Interfacing_Aspects --
11046 -----------------------------
11047
11048 procedure Get_Interfacing_Aspects
11049 (Iface_Asp : Node_Id;
11050 Conv_Asp : out Node_Id;
11051 EN_Asp : out Node_Id;
11052 Expo_Asp : out Node_Id;
11053 Imp_Asp : out Node_Id;
11054 LN_Asp : out Node_Id;
11055 Do_Checks : Boolean := False)
11056 is
11057 procedure Save_Or_Duplication_Error
11058 (Asp : Node_Id;
11059 To : in out Node_Id);
11060 -- Save the value of aspect Asp in node To. If To already has a value,
11061 -- then this is considered a duplicate use of aspect. Emit an error if
11062 -- flag Do_Checks is set.
11063
11064 -------------------------------
11065 -- Save_Or_Duplication_Error --
11066 -------------------------------
11067
11068 procedure Save_Or_Duplication_Error
11069 (Asp : Node_Id;
11070 To : in out Node_Id)
11071 is
11072 begin
11073 -- Detect an extra aspect and issue an error
11074
11075 if Present (To) then
11076 if Do_Checks then
11077 Error_Msg_Name_1 := Chars (Identifier (Asp));
11078 Error_Msg_Sloc := Sloc (To);
11079 Error_Msg_N ("aspect % previously given #", Asp);
11080 end if;
11081
11082 -- Otherwise capture the aspect
11083
11084 else
11085 To := Asp;
11086 end if;
11087 end Save_Or_Duplication_Error;
11088
11089 -- Local variables
11090
11091 Asp : Node_Id;
11092 Asp_Id : Aspect_Id;
11093
11094 -- The following variables capture each individual aspect
11095
11096 Conv : Node_Id := Empty;
11097 EN : Node_Id := Empty;
11098 Expo : Node_Id := Empty;
11099 Imp : Node_Id := Empty;
11100 LN : Node_Id := Empty;
11101
11102 -- Start of processing for Get_Interfacing_Aspects
11103
11104 begin
11105 -- The input interfacing aspect should reside in an aspect specification
11106 -- list.
11107
11108 pragma Assert (Is_List_Member (Iface_Asp));
11109
11110 -- Examine the aspect specifications of the related entity. Find and
11111 -- capture all interfacing aspects. Detect duplicates and emit errors
11112 -- if applicable.
11113
11114 Asp := First (List_Containing (Iface_Asp));
11115 while Present (Asp) loop
11116 Asp_Id := Get_Aspect_Id (Asp);
11117
11118 if Asp_Id = Aspect_Convention then
11119 Save_Or_Duplication_Error (Asp, Conv);
11120
11121 elsif Asp_Id = Aspect_External_Name then
11122 Save_Or_Duplication_Error (Asp, EN);
11123
11124 elsif Asp_Id = Aspect_Export then
11125 Save_Or_Duplication_Error (Asp, Expo);
11126
11127 elsif Asp_Id = Aspect_Import then
11128 Save_Or_Duplication_Error (Asp, Imp);
11129
11130 elsif Asp_Id = Aspect_Link_Name then
11131 Save_Or_Duplication_Error (Asp, LN);
11132 end if;
11133
11134 Next (Asp);
11135 end loop;
11136
11137 Conv_Asp := Conv;
11138 EN_Asp := EN;
11139 Expo_Asp := Expo;
11140 Imp_Asp := Imp;
11141 LN_Asp := LN;
11142 end Get_Interfacing_Aspects;
11143
11144 -------------------------------------
11145 -- Inherit_Aspects_At_Freeze_Point --
11146 -------------------------------------
11147
11148 procedure Inherit_Aspects_At_Freeze_Point (Typ : Entity_Id) is
11149 function Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item
11150 (Rep_Item : Node_Id) return Boolean;
11151 -- This routine checks if Rep_Item is either a pragma or an aspect
11152 -- specification node whose correponding pragma (if any) is present in
11153 -- the Rep Item chain of the entity it has been specified to.
11154
11155 --------------------------------------------------
11156 -- Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item --
11157 --------------------------------------------------
11158
11159 function Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item
11160 (Rep_Item : Node_Id) return Boolean
11161 is
11162 begin
11163 return
11164 Nkind (Rep_Item) = N_Pragma
11165 or else Present_In_Rep_Item
11166 (Entity (Rep_Item), Aspect_Rep_Item (Rep_Item));
11167 end Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item;
11168
11169 -- Start of processing for Inherit_Aspects_At_Freeze_Point
11170
11171 begin
11172 -- A representation item is either subtype-specific (Size and Alignment
11173 -- clauses) or type-related (all others). Subtype-specific aspects may
11174 -- differ for different subtypes of the same type (RM 13.1.8).
11175
11176 -- A derived type inherits each type-related representation aspect of
11177 -- its parent type that was directly specified before the declaration of
11178 -- the derived type (RM 13.1.15).
11179
11180 -- A derived subtype inherits each subtype-specific representation
11181 -- aspect of its parent subtype that was directly specified before the
11182 -- declaration of the derived type (RM 13.1.15).
11183
11184 -- The general processing involves inheriting a representation aspect
11185 -- from a parent type whenever the first rep item (aspect specification,
11186 -- attribute definition clause, pragma) corresponding to the given
11187 -- representation aspect in the rep item chain of Typ, if any, isn't
11188 -- directly specified to Typ but to one of its parents.
11189
11190 -- ??? Note that, for now, just a limited number of representation
11191 -- aspects have been inherited here so far. Many of them are
11192 -- still inherited in Sem_Ch3. This will be fixed soon. Here is
11193 -- a non- exhaustive list of aspects that likely also need to
11194 -- be moved to this routine: Alignment, Component_Alignment,
11195 -- Component_Size, Machine_Radix, Object_Size, Pack, Predicates,
11196 -- Preelaborable_Initialization, RM_Size and Small.
11197
11198 -- In addition, Convention must be propagated from base type to subtype,
11199 -- because the subtype may have been declared on an incomplete view.
11200
11201 if Nkind (Parent (Typ)) = N_Private_Extension_Declaration then
11202 return;
11203 end if;
11204
11205 -- Ada_05/Ada_2005
11206
11207 if not Has_Rep_Item (Typ, Name_Ada_05, Name_Ada_2005, False)
11208 and then Has_Rep_Item (Typ, Name_Ada_05, Name_Ada_2005)
11209 and then Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item
11210 (Get_Rep_Item (Typ, Name_Ada_05, Name_Ada_2005))
11211 then
11212 Set_Is_Ada_2005_Only (Typ);
11213 end if;
11214
11215 -- Ada_12/Ada_2012
11216
11217 if not Has_Rep_Item (Typ, Name_Ada_12, Name_Ada_2012, False)
11218 and then Has_Rep_Item (Typ, Name_Ada_12, Name_Ada_2012)
11219 and then Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item
11220 (Get_Rep_Item (Typ, Name_Ada_12, Name_Ada_2012))
11221 then
11222 Set_Is_Ada_2012_Only (Typ);
11223 end if;
11224
11225 -- Atomic/Shared
11226
11227 if not Has_Rep_Item (Typ, Name_Atomic, Name_Shared, False)
11228 and then Has_Rep_Pragma (Typ, Name_Atomic, Name_Shared)
11229 and then Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item
11230 (Get_Rep_Item (Typ, Name_Atomic, Name_Shared))
11231 then
11232 Set_Is_Atomic (Typ);
11233 Set_Is_Volatile (Typ);
11234 Set_Treat_As_Volatile (Typ);
11235 end if;
11236
11237 -- Convention
11238
11239 if Is_Record_Type (Typ)
11240 and then Typ /= Base_Type (Typ) and then Is_Frozen (Base_Type (Typ))
11241 then
11242 Set_Convention (Typ, Convention (Base_Type (Typ)));
11243 end if;
11244
11245 -- Default_Component_Value
11246
11247 -- Verify that there is no rep_item declared for the type, and there
11248 -- is one coming from an ancestor.
11249
11250 if Is_Array_Type (Typ)
11251 and then Is_Base_Type (Typ)
11252 and then not Has_Rep_Item (Typ, Name_Default_Component_Value, False)
11253 and then Has_Rep_Item (Typ, Name_Default_Component_Value)
11254 then
11255 Set_Default_Aspect_Component_Value (Typ,
11256 Default_Aspect_Component_Value
11257 (Entity (Get_Rep_Item (Typ, Name_Default_Component_Value))));
11258 end if;
11259
11260 -- Default_Value
11261
11262 if Is_Scalar_Type (Typ)
11263 and then Is_Base_Type (Typ)
11264 and then not Has_Rep_Item (Typ, Name_Default_Value, False)
11265 and then Has_Rep_Item (Typ, Name_Default_Value)
11266 then
11267 Set_Has_Default_Aspect (Typ);
11268 Set_Default_Aspect_Value (Typ,
11269 Default_Aspect_Value
11270 (Entity (Get_Rep_Item (Typ, Name_Default_Value))));
11271 end if;
11272
11273 -- Discard_Names
11274
11275 if not Has_Rep_Item (Typ, Name_Discard_Names, False)
11276 and then Has_Rep_Item (Typ, Name_Discard_Names)
11277 and then Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item
11278 (Get_Rep_Item (Typ, Name_Discard_Names))
11279 then
11280 Set_Discard_Names (Typ);
11281 end if;
11282
11283 -- Volatile
11284
11285 if not Has_Rep_Item (Typ, Name_Volatile, False)
11286 and then Has_Rep_Item (Typ, Name_Volatile)
11287 and then Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item
11288 (Get_Rep_Item (Typ, Name_Volatile))
11289 then
11290 Set_Is_Volatile (Typ);
11291 Set_Treat_As_Volatile (Typ);
11292 end if;
11293
11294 -- Volatile_Full_Access
11295
11296 if not Has_Rep_Item (Typ, Name_Volatile_Full_Access, False)
11297 and then Has_Rep_Pragma (Typ, Name_Volatile_Full_Access)
11298 and then Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item
11299 (Get_Rep_Item (Typ, Name_Volatile_Full_Access))
11300 then
11301 Set_Is_Volatile_Full_Access (Typ);
11302 Set_Is_Volatile (Typ);
11303 Set_Treat_As_Volatile (Typ);
11304 end if;
11305
11306 -- Inheritance for derived types only
11307
11308 if Is_Derived_Type (Typ) then
11309 declare
11310 Bas_Typ : constant Entity_Id := Base_Type (Typ);
11311 Imp_Bas_Typ : constant Entity_Id := Implementation_Base_Type (Typ);
11312
11313 begin
11314 -- Atomic_Components
11315
11316 if not Has_Rep_Item (Typ, Name_Atomic_Components, False)
11317 and then Has_Rep_Item (Typ, Name_Atomic_Components)
11318 and then Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item
11319 (Get_Rep_Item (Typ, Name_Atomic_Components))
11320 then
11321 Set_Has_Atomic_Components (Imp_Bas_Typ);
11322 end if;
11323
11324 -- Volatile_Components
11325
11326 if not Has_Rep_Item (Typ, Name_Volatile_Components, False)
11327 and then Has_Rep_Item (Typ, Name_Volatile_Components)
11328 and then Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item
11329 (Get_Rep_Item (Typ, Name_Volatile_Components))
11330 then
11331 Set_Has_Volatile_Components (Imp_Bas_Typ);
11332 end if;
11333
11334 -- Finalize_Storage_Only
11335
11336 if not Has_Rep_Pragma (Typ, Name_Finalize_Storage_Only, False)
11337 and then Has_Rep_Pragma (Typ, Name_Finalize_Storage_Only)
11338 then
11339 Set_Finalize_Storage_Only (Bas_Typ);
11340 end if;
11341
11342 -- Universal_Aliasing
11343
11344 if not Has_Rep_Item (Typ, Name_Universal_Aliasing, False)
11345 and then Has_Rep_Item (Typ, Name_Universal_Aliasing)
11346 and then Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item
11347 (Get_Rep_Item (Typ, Name_Universal_Aliasing))
11348 then
11349 Set_Universal_Aliasing (Imp_Bas_Typ);
11350 end if;
11351
11352 -- Bit_Order
11353
11354 if Is_Record_Type (Typ) then
11355 if not Has_Rep_Item (Typ, Name_Bit_Order, False)
11356 and then Has_Rep_Item (Typ, Name_Bit_Order)
11357 then
11358 Set_Reverse_Bit_Order (Bas_Typ,
11359 Reverse_Bit_Order (Entity (Name
11360 (Get_Rep_Item (Typ, Name_Bit_Order)))));
11361 end if;
11362 end if;
11363
11364 -- Scalar_Storage_Order
11365
11366 -- Note: the aspect is specified on a first subtype, but recorded
11367 -- in a flag of the base type!
11368
11369 if (Is_Record_Type (Typ) or else Is_Array_Type (Typ))
11370 and then Typ = Bas_Typ
11371 then
11372 -- For a type extension, always inherit from parent; otherwise
11373 -- inherit if no default applies. Note: we do not check for
11374 -- an explicit rep item on the parent type when inheriting,
11375 -- because the parent SSO may itself have been set by default.
11376
11377 if not Has_Rep_Item (First_Subtype (Typ),
11378 Name_Scalar_Storage_Order, False)
11379 and then (Is_Tagged_Type (Bas_Typ)
11380 or else not (SSO_Set_Low_By_Default (Bas_Typ)
11381 or else
11382 SSO_Set_High_By_Default (Bas_Typ)))
11383 then
11384 Set_Reverse_Storage_Order (Bas_Typ,
11385 Reverse_Storage_Order
11386 (Implementation_Base_Type (Etype (Bas_Typ))));
11387
11388 -- Clear default SSO indications, since the inherited aspect
11389 -- which was set explicitly overrides the default.
11390
11391 Set_SSO_Set_Low_By_Default (Bas_Typ, False);
11392 Set_SSO_Set_High_By_Default (Bas_Typ, False);
11393 end if;
11394 end if;
11395 end;
11396 end if;
11397 end Inherit_Aspects_At_Freeze_Point;
11398
11399 ----------------
11400 -- Initialize --
11401 ----------------
11402
11403 procedure Initialize is
11404 begin
11405 Address_Clause_Checks.Init;
11406 Unchecked_Conversions.Init;
11407
11408 if AAMP_On_Target then
11409 Independence_Checks.Init;
11410 end if;
11411 end Initialize;
11412
11413 ---------------------------
11414 -- Install_Discriminants --
11415 ---------------------------
11416
11417 procedure Install_Discriminants (E : Entity_Id) is
11418 Disc : Entity_Id;
11419 Prev : Entity_Id;
11420 begin
11421 Disc := First_Discriminant (E);
11422 while Present (Disc) loop
11423 Prev := Current_Entity (Disc);
11424 Set_Current_Entity (Disc);
11425 Set_Is_Immediately_Visible (Disc);
11426 Set_Homonym (Disc, Prev);
11427 Next_Discriminant (Disc);
11428 end loop;
11429 end Install_Discriminants;
11430
11431 -------------------------
11432 -- Is_Operational_Item --
11433 -------------------------
11434
11435 function Is_Operational_Item (N : Node_Id) return Boolean is
11436 begin
11437 if Nkind (N) /= N_Attribute_Definition_Clause then
11438 return False;
11439
11440 else
11441 declare
11442 Id : constant Attribute_Id := Get_Attribute_Id (Chars (N));
11443 begin
11444
11445 -- List of operational items is given in AARM 13.1(8.mm/1).
11446 -- It is clearly incomplete, as it does not include iterator
11447 -- aspects, among others.
11448
11449 return Id = Attribute_Constant_Indexing
11450 or else Id = Attribute_Default_Iterator
11451 or else Id = Attribute_Implicit_Dereference
11452 or else Id = Attribute_Input
11453 or else Id = Attribute_Iterator_Element
11454 or else Id = Attribute_Iterable
11455 or else Id = Attribute_Output
11456 or else Id = Attribute_Read
11457 or else Id = Attribute_Variable_Indexing
11458 or else Id = Attribute_Write
11459 or else Id = Attribute_External_Tag;
11460 end;
11461 end if;
11462 end Is_Operational_Item;
11463
11464 -------------------------
11465 -- Is_Predicate_Static --
11466 -------------------------
11467
11468 -- Note: the basic legality of the expression has already been checked, so
11469 -- we don't need to worry about cases or ranges on strings for example.
11470
11471 function Is_Predicate_Static
11472 (Expr : Node_Id;
11473 Nam : Name_Id) return Boolean
11474 is
11475 function All_Static_Case_Alternatives (L : List_Id) return Boolean;
11476 -- Given a list of case expression alternatives, returns True if all
11477 -- the alternatives are static (have all static choices, and a static
11478 -- expression).
11479
11480 function All_Static_Choices (L : List_Id) return Boolean;
11481 -- Returns true if all elements of the list are OK static choices
11482 -- as defined below for Is_Static_Choice. Used for case expression
11483 -- alternatives and for the right operand of a membership test. An
11484 -- others_choice is static if the corresponding expression is static.
11485 -- The staticness of the bounds is checked separately.
11486
11487 function Is_Static_Choice (N : Node_Id) return Boolean;
11488 -- Returns True if N represents a static choice (static subtype, or
11489 -- static subtype indication, or static expression, or static range).
11490 --
11491 -- Note that this is a bit more inclusive than we actually need
11492 -- (in particular membership tests do not allow the use of subtype
11493 -- indications). But that doesn't matter, we have already checked
11494 -- that the construct is legal to get this far.
11495
11496 function Is_Type_Ref (N : Node_Id) return Boolean;
11497 pragma Inline (Is_Type_Ref);
11498 -- Returns True if N is a reference to the type for the predicate in the
11499 -- expression (i.e. if it is an identifier whose Chars field matches the
11500 -- Nam given in the call). N must not be parenthesized, if the type name
11501 -- appears in parens, this routine will return False.
11502
11503 ----------------------------------
11504 -- All_Static_Case_Alternatives --
11505 ----------------------------------
11506
11507 function All_Static_Case_Alternatives (L : List_Id) return Boolean is
11508 N : Node_Id;
11509
11510 begin
11511 N := First (L);
11512 while Present (N) loop
11513 if not (All_Static_Choices (Discrete_Choices (N))
11514 and then Is_OK_Static_Expression (Expression (N)))
11515 then
11516 return False;
11517 end if;
11518
11519 Next (N);
11520 end loop;
11521
11522 return True;
11523 end All_Static_Case_Alternatives;
11524
11525 ------------------------
11526 -- All_Static_Choices --
11527 ------------------------
11528
11529 function All_Static_Choices (L : List_Id) return Boolean is
11530 N : Node_Id;
11531
11532 begin
11533 N := First (L);
11534 while Present (N) loop
11535 if not Is_Static_Choice (N) then
11536 return False;
11537 end if;
11538
11539 Next (N);
11540 end loop;
11541
11542 return True;
11543 end All_Static_Choices;
11544
11545 ----------------------
11546 -- Is_Static_Choice --
11547 ----------------------
11548
11549 function Is_Static_Choice (N : Node_Id) return Boolean is
11550 begin
11551 return Nkind (N) = N_Others_Choice
11552 or else Is_OK_Static_Expression (N)
11553 or else (Is_Entity_Name (N) and then Is_Type (Entity (N))
11554 and then Is_OK_Static_Subtype (Entity (N)))
11555 or else (Nkind (N) = N_Subtype_Indication
11556 and then Is_OK_Static_Subtype (Entity (N)))
11557 or else (Nkind (N) = N_Range and then Is_OK_Static_Range (N));
11558 end Is_Static_Choice;
11559
11560 -----------------
11561 -- Is_Type_Ref --
11562 -----------------
11563
11564 function Is_Type_Ref (N : Node_Id) return Boolean is
11565 begin
11566 return Nkind (N) = N_Identifier
11567 and then Chars (N) = Nam
11568 and then Paren_Count (N) = 0;
11569 end Is_Type_Ref;
11570
11571 -- Start of processing for Is_Predicate_Static
11572
11573 begin
11574 -- Predicate_Static means one of the following holds. Numbers are the
11575 -- corresponding paragraph numbers in (RM 3.2.4(16-22)).
11576
11577 -- 16: A static expression
11578
11579 if Is_OK_Static_Expression (Expr) then
11580 return True;
11581
11582 -- 17: A membership test whose simple_expression is the current
11583 -- instance, and whose membership_choice_list meets the requirements
11584 -- for a static membership test.
11585
11586 elsif Nkind (Expr) in N_Membership_Test
11587 and then ((Present (Right_Opnd (Expr))
11588 and then Is_Static_Choice (Right_Opnd (Expr)))
11589 or else
11590 (Present (Alternatives (Expr))
11591 and then All_Static_Choices (Alternatives (Expr))))
11592 then
11593 return True;
11594
11595 -- 18. A case_expression whose selecting_expression is the current
11596 -- instance, and whose dependent expressions are static expressions.
11597
11598 elsif Nkind (Expr) = N_Case_Expression
11599 and then Is_Type_Ref (Expression (Expr))
11600 and then All_Static_Case_Alternatives (Alternatives (Expr))
11601 then
11602 return True;
11603
11604 -- 19. A call to a predefined equality or ordering operator, where one
11605 -- operand is the current instance, and the other is a static
11606 -- expression.
11607
11608 -- Note: the RM is clearly wrong here in not excluding string types.
11609 -- Without this exclusion, we would allow expressions like X > "ABC"
11610 -- to be considered as predicate-static, which is clearly not intended,
11611 -- since the idea is for predicate-static to be a subset of normal
11612 -- static expressions (and "DEF" > "ABC" is not a static expression).
11613
11614 -- However, we do allow internally generated (not from source) equality
11615 -- and inequality operations to be valid on strings (this helps deal
11616 -- with cases where we transform A in "ABC" to A = "ABC).
11617
11618 elsif Nkind (Expr) in N_Op_Compare
11619 and then ((not Is_String_Type (Etype (Left_Opnd (Expr))))
11620 or else (Nkind_In (Expr, N_Op_Eq, N_Op_Ne)
11621 and then not Comes_From_Source (Expr)))
11622 and then ((Is_Type_Ref (Left_Opnd (Expr))
11623 and then Is_OK_Static_Expression (Right_Opnd (Expr)))
11624 or else
11625 (Is_Type_Ref (Right_Opnd (Expr))
11626 and then Is_OK_Static_Expression (Left_Opnd (Expr))))
11627 then
11628 return True;
11629
11630 -- 20. A call to a predefined boolean logical operator, where each
11631 -- operand is predicate-static.
11632
11633 elsif (Nkind_In (Expr, N_Op_And, N_Op_Or, N_Op_Xor)
11634 and then Is_Predicate_Static (Left_Opnd (Expr), Nam)
11635 and then Is_Predicate_Static (Right_Opnd (Expr), Nam))
11636 or else
11637 (Nkind (Expr) = N_Op_Not
11638 and then Is_Predicate_Static (Right_Opnd (Expr), Nam))
11639 then
11640 return True;
11641
11642 -- 21. A short-circuit control form where both operands are
11643 -- predicate-static.
11644
11645 elsif Nkind (Expr) in N_Short_Circuit
11646 and then Is_Predicate_Static (Left_Opnd (Expr), Nam)
11647 and then Is_Predicate_Static (Right_Opnd (Expr), Nam)
11648 then
11649 return True;
11650
11651 -- 22. A parenthesized predicate-static expression. This does not
11652 -- require any special test, since we just ignore paren levels in
11653 -- all the cases above.
11654
11655 -- One more test that is an implementation artifact caused by the fact
11656 -- that we are analyzing not the original expression, but the generated
11657 -- expression in the body of the predicate function. This can include
11658 -- references to inherited predicates, so that the expression we are
11659 -- processing looks like:
11660
11661 -- xxPredicate (typ (Inns)) and then expression
11662
11663 -- Where the call is to a Predicate function for an inherited predicate.
11664 -- We simply ignore such a call, which could be to either a dynamic or
11665 -- a static predicate. Note that if the parent predicate is dynamic then
11666 -- eventually this type will be marked as dynamic, but you are allowed
11667 -- to specify a static predicate for a subtype which is inheriting a
11668 -- dynamic predicate, so the static predicate validation here ignores
11669 -- the inherited predicate even if it is dynamic.
11670 -- In all cases, a static predicate can only apply to a scalar type.
11671
11672 elsif Nkind (Expr) = N_Function_Call
11673 and then Is_Predicate_Function (Entity (Name (Expr)))
11674 and then Is_Scalar_Type (Etype (First_Entity (Entity (Name (Expr)))))
11675 then
11676 return True;
11677
11678 -- That's an exhaustive list of tests, all other cases are not
11679 -- predicate-static, so we return False.
11680
11681 else
11682 return False;
11683 end if;
11684 end Is_Predicate_Static;
11685
11686 ---------------------
11687 -- Kill_Rep_Clause --
11688 ---------------------
11689
11690 procedure Kill_Rep_Clause (N : Node_Id) is
11691 begin
11692 pragma Assert (Ignore_Rep_Clauses);
11693
11694 -- Note: we use Replace rather than Rewrite, because we don't want
11695 -- ASIS to be able to use Original_Node to dig out the (undecorated)
11696 -- rep clause that is being replaced.
11697
11698 Replace (N, Make_Null_Statement (Sloc (N)));
11699
11700 -- The null statement must be marked as not coming from source. This is
11701 -- so that ASIS ignores it, and also the back end does not expect bogus
11702 -- "from source" null statements in weird places (e.g. in declarative
11703 -- regions where such null statements are not allowed).
11704
11705 Set_Comes_From_Source (N, False);
11706 end Kill_Rep_Clause;
11707
11708 ------------------
11709 -- Minimum_Size --
11710 ------------------
11711
11712 function Minimum_Size
11713 (T : Entity_Id;
11714 Biased : Boolean := False) return Nat
11715 is
11716 Lo : Uint := No_Uint;
11717 Hi : Uint := No_Uint;
11718 LoR : Ureal := No_Ureal;
11719 HiR : Ureal := No_Ureal;
11720 LoSet : Boolean := False;
11721 HiSet : Boolean := False;
11722 B : Uint;
11723 S : Nat;
11724 Ancest : Entity_Id;
11725 R_Typ : constant Entity_Id := Root_Type (T);
11726
11727 begin
11728 -- If bad type, return 0
11729
11730 if T = Any_Type then
11731 return 0;
11732
11733 -- For generic types, just return zero. There cannot be any legitimate
11734 -- need to know such a size, but this routine may be called with a
11735 -- generic type as part of normal processing.
11736
11737 elsif Is_Generic_Type (R_Typ) or else R_Typ = Any_Type then
11738 return 0;
11739
11740 -- Access types (cannot have size smaller than System.Address)
11741
11742 elsif Is_Access_Type (T) then
11743 return System_Address_Size;
11744
11745 -- Floating-point types
11746
11747 elsif Is_Floating_Point_Type (T) then
11748 return UI_To_Int (Esize (R_Typ));
11749
11750 -- Discrete types
11751
11752 elsif Is_Discrete_Type (T) then
11753
11754 -- The following loop is looking for the nearest compile time known
11755 -- bounds following the ancestor subtype chain. The idea is to find
11756 -- the most restrictive known bounds information.
11757
11758 Ancest := T;
11759 loop
11760 if Ancest = Any_Type or else Etype (Ancest) = Any_Type then
11761 return 0;
11762 end if;
11763
11764 if not LoSet then
11765 if Compile_Time_Known_Value (Type_Low_Bound (Ancest)) then
11766 Lo := Expr_Rep_Value (Type_Low_Bound (Ancest));
11767 LoSet := True;
11768 exit when HiSet;
11769 end if;
11770 end if;
11771
11772 if not HiSet then
11773 if Compile_Time_Known_Value (Type_High_Bound (Ancest)) then
11774 Hi := Expr_Rep_Value (Type_High_Bound (Ancest));
11775 HiSet := True;
11776 exit when LoSet;
11777 end if;
11778 end if;
11779
11780 Ancest := Ancestor_Subtype (Ancest);
11781
11782 if No (Ancest) then
11783 Ancest := Base_Type (T);
11784
11785 if Is_Generic_Type (Ancest) then
11786 return 0;
11787 end if;
11788 end if;
11789 end loop;
11790
11791 -- Fixed-point types. We can't simply use Expr_Value to get the
11792 -- Corresponding_Integer_Value values of the bounds, since these do not
11793 -- get set till the type is frozen, and this routine can be called
11794 -- before the type is frozen. Similarly the test for bounds being static
11795 -- needs to include the case where we have unanalyzed real literals for
11796 -- the same reason.
11797
11798 elsif Is_Fixed_Point_Type (T) then
11799
11800 -- The following loop is looking for the nearest compile time known
11801 -- bounds following the ancestor subtype chain. The idea is to find
11802 -- the most restrictive known bounds information.
11803
11804 Ancest := T;
11805 loop
11806 if Ancest = Any_Type or else Etype (Ancest) = Any_Type then
11807 return 0;
11808 end if;
11809
11810 -- Note: In the following two tests for LoSet and HiSet, it may
11811 -- seem redundant to test for N_Real_Literal here since normally
11812 -- one would assume that the test for the value being known at
11813 -- compile time includes this case. However, there is a glitch.
11814 -- If the real literal comes from folding a non-static expression,
11815 -- then we don't consider any non- static expression to be known
11816 -- at compile time if we are in configurable run time mode (needed
11817 -- in some cases to give a clearer definition of what is and what
11818 -- is not accepted). So the test is indeed needed. Without it, we
11819 -- would set neither Lo_Set nor Hi_Set and get an infinite loop.
11820
11821 if not LoSet then
11822 if Nkind (Type_Low_Bound (Ancest)) = N_Real_Literal
11823 or else Compile_Time_Known_Value (Type_Low_Bound (Ancest))
11824 then
11825 LoR := Expr_Value_R (Type_Low_Bound (Ancest));
11826 LoSet := True;
11827 exit when HiSet;
11828 end if;
11829 end if;
11830
11831 if not HiSet then
11832 if Nkind (Type_High_Bound (Ancest)) = N_Real_Literal
11833 or else Compile_Time_Known_Value (Type_High_Bound (Ancest))
11834 then
11835 HiR := Expr_Value_R (Type_High_Bound (Ancest));
11836 HiSet := True;
11837 exit when LoSet;
11838 end if;
11839 end if;
11840
11841 Ancest := Ancestor_Subtype (Ancest);
11842
11843 if No (Ancest) then
11844 Ancest := Base_Type (T);
11845
11846 if Is_Generic_Type (Ancest) then
11847 return 0;
11848 end if;
11849 end if;
11850 end loop;
11851
11852 Lo := UR_To_Uint (LoR / Small_Value (T));
11853 Hi := UR_To_Uint (HiR / Small_Value (T));
11854
11855 -- No other types allowed
11856
11857 else
11858 raise Program_Error;
11859 end if;
11860
11861 -- Fall through with Hi and Lo set. Deal with biased case
11862
11863 if (Biased
11864 and then not Is_Fixed_Point_Type (T)
11865 and then not (Is_Enumeration_Type (T)
11866 and then Has_Non_Standard_Rep (T)))
11867 or else Has_Biased_Representation (T)
11868 then
11869 Hi := Hi - Lo;
11870 Lo := Uint_0;
11871 end if;
11872
11873 -- Null range case, size is always zero. We only do this in the discrete
11874 -- type case, since that's the odd case that came up. Probably we should
11875 -- also do this in the fixed-point case, but doing so causes peculiar
11876 -- gigi failures, and it is not worth worrying about this incredibly
11877 -- marginal case (explicit null-range fixed-point type declarations)???
11878
11879 if Lo > Hi and then Is_Discrete_Type (T) then
11880 S := 0;
11881
11882 -- Signed case. Note that we consider types like range 1 .. -1 to be
11883 -- signed for the purpose of computing the size, since the bounds have
11884 -- to be accommodated in the base type.
11885
11886 elsif Lo < 0 or else Hi < 0 then
11887 S := 1;
11888 B := Uint_1;
11889
11890 -- S = size, B = 2 ** (size - 1) (can accommodate -B .. +(B - 1))
11891 -- Note that we accommodate the case where the bounds cross. This
11892 -- can happen either because of the way the bounds are declared
11893 -- or because of the algorithm in Freeze_Fixed_Point_Type.
11894
11895 while Lo < -B
11896 or else Hi < -B
11897 or else Lo >= B
11898 or else Hi >= B
11899 loop
11900 B := Uint_2 ** S;
11901 S := S + 1;
11902 end loop;
11903
11904 -- Unsigned case
11905
11906 else
11907 -- If both bounds are positive, make sure that both are represen-
11908 -- table in the case where the bounds are crossed. This can happen
11909 -- either because of the way the bounds are declared, or because of
11910 -- the algorithm in Freeze_Fixed_Point_Type.
11911
11912 if Lo > Hi then
11913 Hi := Lo;
11914 end if;
11915
11916 -- S = size, (can accommodate 0 .. (2**size - 1))
11917
11918 S := 0;
11919 while Hi >= Uint_2 ** S loop
11920 S := S + 1;
11921 end loop;
11922 end if;
11923
11924 return S;
11925 end Minimum_Size;
11926
11927 ---------------------------
11928 -- New_Stream_Subprogram --
11929 ---------------------------
11930
11931 procedure New_Stream_Subprogram
11932 (N : Node_Id;
11933 Ent : Entity_Id;
11934 Subp : Entity_Id;
11935 Nam : TSS_Name_Type)
11936 is
11937 Loc : constant Source_Ptr := Sloc (N);
11938 Sname : constant Name_Id := Make_TSS_Name (Base_Type (Ent), Nam);
11939 Subp_Id : Entity_Id;
11940 Subp_Decl : Node_Id;
11941 F : Entity_Id;
11942 Etyp : Entity_Id;
11943
11944 Defer_Declaration : constant Boolean :=
11945 Is_Tagged_Type (Ent) or else Is_Private_Type (Ent);
11946 -- For a tagged type, there is a declaration for each stream attribute
11947 -- at the freeze point, and we must generate only a completion of this
11948 -- declaration. We do the same for private types, because the full view
11949 -- might be tagged. Otherwise we generate a declaration at the point of
11950 -- the attribute definition clause. If the attribute definition comes
11951 -- from an aspect specification the declaration is part of the freeze
11952 -- actions of the type.
11953
11954 function Build_Spec return Node_Id;
11955 -- Used for declaration and renaming declaration, so that this is
11956 -- treated as a renaming_as_body.
11957
11958 ----------------
11959 -- Build_Spec --
11960 ----------------
11961
11962 function Build_Spec return Node_Id is
11963 Out_P : constant Boolean := (Nam = TSS_Stream_Read);
11964 Formals : List_Id;
11965 Spec : Node_Id;
11966 T_Ref : constant Node_Id := New_Occurrence_Of (Etyp, Loc);
11967
11968 begin
11969 Subp_Id := Make_Defining_Identifier (Loc, Sname);
11970
11971 -- S : access Root_Stream_Type'Class
11972
11973 Formals := New_List (
11974 Make_Parameter_Specification (Loc,
11975 Defining_Identifier =>
11976 Make_Defining_Identifier (Loc, Name_S),
11977 Parameter_Type =>
11978 Make_Access_Definition (Loc,
11979 Subtype_Mark =>
11980 New_Occurrence_Of (
11981 Designated_Type (Etype (F)), Loc))));
11982
11983 if Nam = TSS_Stream_Input then
11984 Spec :=
11985 Make_Function_Specification (Loc,
11986 Defining_Unit_Name => Subp_Id,
11987 Parameter_Specifications => Formals,
11988 Result_Definition => T_Ref);
11989 else
11990 -- V : [out] T
11991
11992 Append_To (Formals,
11993 Make_Parameter_Specification (Loc,
11994 Defining_Identifier => Make_Defining_Identifier (Loc, Name_V),
11995 Out_Present => Out_P,
11996 Parameter_Type => T_Ref));
11997
11998 Spec :=
11999 Make_Procedure_Specification (Loc,
12000 Defining_Unit_Name => Subp_Id,
12001 Parameter_Specifications => Formals);
12002 end if;
12003
12004 return Spec;
12005 end Build_Spec;
12006
12007 -- Start of processing for New_Stream_Subprogram
12008
12009 begin
12010 F := First_Formal (Subp);
12011
12012 if Ekind (Subp) = E_Procedure then
12013 Etyp := Etype (Next_Formal (F));
12014 else
12015 Etyp := Etype (Subp);
12016 end if;
12017
12018 -- Prepare subprogram declaration and insert it as an action on the
12019 -- clause node. The visibility for this entity is used to test for
12020 -- visibility of the attribute definition clause (in the sense of
12021 -- 8.3(23) as amended by AI-195).
12022
12023 if not Defer_Declaration then
12024 Subp_Decl :=
12025 Make_Subprogram_Declaration (Loc,
12026 Specification => Build_Spec);
12027
12028 -- For a tagged type, there is always a visible declaration for each
12029 -- stream TSS (it is a predefined primitive operation), and the
12030 -- completion of this declaration occurs at the freeze point, which is
12031 -- not always visible at places where the attribute definition clause is
12032 -- visible. So, we create a dummy entity here for the purpose of
12033 -- tracking the visibility of the attribute definition clause itself.
12034
12035 else
12036 Subp_Id :=
12037 Make_Defining_Identifier (Loc, New_External_Name (Sname, 'V'));
12038 Subp_Decl :=
12039 Make_Object_Declaration (Loc,
12040 Defining_Identifier => Subp_Id,
12041 Object_Definition => New_Occurrence_Of (Standard_Boolean, Loc));
12042 end if;
12043
12044 if not Defer_Declaration
12045 and then From_Aspect_Specification (N)
12046 and then Has_Delayed_Freeze (Ent)
12047 then
12048 Append_Freeze_Action (Ent, Subp_Decl);
12049
12050 else
12051 Insert_Action (N, Subp_Decl);
12052 Set_Entity (N, Subp_Id);
12053 end if;
12054
12055 Subp_Decl :=
12056 Make_Subprogram_Renaming_Declaration (Loc,
12057 Specification => Build_Spec,
12058 Name => New_Occurrence_Of (Subp, Loc));
12059
12060 if Defer_Declaration then
12061 Set_TSS (Base_Type (Ent), Subp_Id);
12062
12063 else
12064 if From_Aspect_Specification (N) then
12065 Append_Freeze_Action (Ent, Subp_Decl);
12066 else
12067 Insert_Action (N, Subp_Decl);
12068 end if;
12069
12070 Copy_TSS (Subp_Id, Base_Type (Ent));
12071 end if;
12072 end New_Stream_Subprogram;
12073
12074 ------------------------------------------
12075 -- Push_Scope_And_Install_Discriminants --
12076 ------------------------------------------
12077
12078 procedure Push_Scope_And_Install_Discriminants (E : Entity_Id) is
12079 begin
12080 if Has_Discriminants (E) then
12081 Push_Scope (E);
12082
12083 -- Make the discriminants visible for type declarations and protected
12084 -- type declarations, not for subtype declarations (RM 13.1.1 (12/3))
12085
12086 if Nkind (Parent (E)) /= N_Subtype_Declaration then
12087 Install_Discriminants (E);
12088 end if;
12089 end if;
12090 end Push_Scope_And_Install_Discriminants;
12091
12092 ------------------------
12093 -- Rep_Item_Too_Early --
12094 ------------------------
12095
12096 function Rep_Item_Too_Early (T : Entity_Id; N : Node_Id) return Boolean is
12097 begin
12098 -- Cannot apply non-operational rep items to generic types
12099
12100 if Is_Operational_Item (N) then
12101 return False;
12102
12103 elsif Is_Type (T)
12104 and then Is_Generic_Type (Root_Type (T))
12105 and then (Nkind (N) /= N_Pragma
12106 or else Get_Pragma_Id (N) /= Pragma_Convention)
12107 then
12108 Error_Msg_N ("representation item not allowed for generic type", N);
12109 return True;
12110 end if;
12111
12112 -- Otherwise check for incomplete type
12113
12114 if Is_Incomplete_Or_Private_Type (T)
12115 and then No (Underlying_Type (T))
12116 and then
12117 (Nkind (N) /= N_Pragma
12118 or else Get_Pragma_Id (N) /= Pragma_Import)
12119 then
12120 Error_Msg_N
12121 ("representation item must be after full type declaration", N);
12122 return True;
12123
12124 -- If the type has incomplete components, a representation clause is
12125 -- illegal but stream attributes and Convention pragmas are correct.
12126
12127 elsif Has_Private_Component (T) then
12128 if Nkind (N) = N_Pragma then
12129 return False;
12130
12131 else
12132 Error_Msg_N
12133 ("representation item must appear after type is fully defined",
12134 N);
12135 return True;
12136 end if;
12137 else
12138 return False;
12139 end if;
12140 end Rep_Item_Too_Early;
12141
12142 -----------------------
12143 -- Rep_Item_Too_Late --
12144 -----------------------
12145
12146 function Rep_Item_Too_Late
12147 (T : Entity_Id;
12148 N : Node_Id;
12149 FOnly : Boolean := False) return Boolean
12150 is
12151 S : Entity_Id;
12152 Parent_Type : Entity_Id;
12153
12154 procedure No_Type_Rep_Item;
12155 -- Output message indicating that no type-related aspects can be
12156 -- specified due to some property of the parent type.
12157
12158 procedure Too_Late;
12159 -- Output message for an aspect being specified too late
12160
12161 -- Note that neither of the above errors is considered a serious one,
12162 -- since the effect is simply that we ignore the representation clause
12163 -- in these cases.
12164 -- Is this really true? In any case if we make this change we must
12165 -- document the requirement in the spec of Rep_Item_Too_Late that
12166 -- if True is returned, then the rep item must be completely ignored???
12167
12168 ----------------------
12169 -- No_Type_Rep_Item --
12170 ----------------------
12171
12172 procedure No_Type_Rep_Item is
12173 begin
12174 Error_Msg_N ("|type-related representation item not permitted!", N);
12175 end No_Type_Rep_Item;
12176
12177 --------------
12178 -- Too_Late --
12179 --------------
12180
12181 procedure Too_Late is
12182 begin
12183 -- Other compilers seem more relaxed about rep items appearing too
12184 -- late. Since analysis tools typically don't care about rep items
12185 -- anyway, no reason to be too strict about this.
12186
12187 if not Relaxed_RM_Semantics then
12188 Error_Msg_N ("|representation item appears too late!", N);
12189 end if;
12190 end Too_Late;
12191
12192 -- Start of processing for Rep_Item_Too_Late
12193
12194 begin
12195 -- First make sure entity is not frozen (RM 13.1(9))
12196
12197 if Is_Frozen (T)
12198
12199 -- Exclude imported types, which may be frozen if they appear in a
12200 -- representation clause for a local type.
12201
12202 and then not From_Limited_With (T)
12203
12204 -- Exclude generated entities (not coming from source). The common
12205 -- case is when we generate a renaming which prematurely freezes the
12206 -- renamed internal entity, but we still want to be able to set copies
12207 -- of attribute values such as Size/Alignment.
12208
12209 and then Comes_From_Source (T)
12210 then
12211 -- A self-referential aspect is illegal if it forces freezing the
12212 -- entity before the corresponding pragma has been analyzed.
12213
12214 if Nkind_In (N, N_Attribute_Definition_Clause, N_Pragma)
12215 and then From_Aspect_Specification (N)
12216 then
12217 Error_Msg_NE
12218 ("aspect specification causes premature freezing of&", T, N);
12219 Set_Has_Delayed_Freeze (T, False);
12220 return True;
12221 end if;
12222
12223 Too_Late;
12224 S := First_Subtype (T);
12225
12226 if Present (Freeze_Node (S)) then
12227 if not Relaxed_RM_Semantics then
12228 Error_Msg_NE
12229 ("??no more representation items for }", Freeze_Node (S), S);
12230 end if;
12231 end if;
12232
12233 return True;
12234
12235 -- Check for case of untagged derived type whose parent either has
12236 -- primitive operations, or is a by reference type (RM 13.1(10)). In
12237 -- this case we do not output a Too_Late message, since there is no
12238 -- earlier point where the rep item could be placed to make it legal.
12239
12240 elsif Is_Type (T)
12241 and then not FOnly
12242 and then Is_Derived_Type (T)
12243 and then not Is_Tagged_Type (T)
12244 then
12245 Parent_Type := Etype (Base_Type (T));
12246
12247 if Has_Primitive_Operations (Parent_Type) then
12248 No_Type_Rep_Item;
12249
12250 if not Relaxed_RM_Semantics then
12251 Error_Msg_NE
12252 ("\parent type & has primitive operations!", N, Parent_Type);
12253 end if;
12254
12255 return True;
12256
12257 elsif Is_By_Reference_Type (Parent_Type) then
12258 No_Type_Rep_Item;
12259
12260 if not Relaxed_RM_Semantics then
12261 Error_Msg_NE
12262 ("\parent type & is a by reference type!", N, Parent_Type);
12263 end if;
12264
12265 return True;
12266 end if;
12267 end if;
12268
12269 -- No error, but one more warning to consider. The RM (surprisingly)
12270 -- allows this pattern:
12271
12272 -- type S is ...
12273 -- primitive operations for S
12274 -- type R is new S;
12275 -- rep clause for S
12276
12277 -- Meaning that calls on the primitive operations of S for values of
12278 -- type R may require possibly expensive implicit conversion operations.
12279 -- This is not an error, but is worth a warning.
12280
12281 if not Relaxed_RM_Semantics and then Is_Type (T) then
12282 declare
12283 DTL : constant Entity_Id := Derived_Type_Link (Base_Type (T));
12284
12285 begin
12286 if Present (DTL)
12287 and then Has_Primitive_Operations (Base_Type (T))
12288
12289 -- For now, do not generate this warning for the case of aspect
12290 -- specification using Ada 2012 syntax, since we get wrong
12291 -- messages we do not understand. The whole business of derived
12292 -- types and rep items seems a bit confused when aspects are
12293 -- used, since the aspects are not evaluated till freeze time.
12294
12295 and then not From_Aspect_Specification (N)
12296 then
12297 Error_Msg_Sloc := Sloc (DTL);
12298 Error_Msg_N
12299 ("representation item for& appears after derived type "
12300 & "declaration#??", N);
12301 Error_Msg_NE
12302 ("\may result in implicit conversions for primitive "
12303 & "operations of&??", N, T);
12304 Error_Msg_NE
12305 ("\to change representations when called with arguments "
12306 & "of type&??", N, DTL);
12307 end if;
12308 end;
12309 end if;
12310
12311 -- No error, link item into head of chain of rep items for the entity,
12312 -- but avoid chaining if we have an overloadable entity, and the pragma
12313 -- is one that can apply to multiple overloaded entities.
12314
12315 if Is_Overloadable (T) and then Nkind (N) = N_Pragma then
12316 declare
12317 Pname : constant Name_Id := Pragma_Name (N);
12318 begin
12319 if Nam_In (Pname, Name_Convention, Name_Import, Name_Export,
12320 Name_External, Name_Interface)
12321 then
12322 return False;
12323 end if;
12324 end;
12325 end if;
12326
12327 Record_Rep_Item (T, N);
12328 return False;
12329 end Rep_Item_Too_Late;
12330
12331 -------------------------------------
12332 -- Replace_Type_References_Generic --
12333 -------------------------------------
12334
12335 procedure Replace_Type_References_Generic (N : Node_Id; T : Entity_Id) is
12336 TName : constant Name_Id := Chars (T);
12337
12338 function Replace_Type_Ref (N : Node_Id) return Traverse_Result;
12339 -- Processes a single node in the traversal procedure below, checking
12340 -- if node N should be replaced, and if so, doing the replacement.
12341
12342 function Visible_Component (Comp : Name_Id) return Entity_Id;
12343 -- Given an identifier in the expression, check whether there is a
12344 -- discriminant or component of the type that is directy visible, and
12345 -- rewrite it as the corresponding selected component of the formal of
12346 -- the subprogram. The entity is located by a sequential search, which
12347 -- seems acceptable given the typical size of component lists and check
12348 -- expressions. Possible optimization ???
12349
12350 ----------------------
12351 -- Replace_Type_Ref --
12352 ----------------------
12353
12354 function Replace_Type_Ref (N : Node_Id) return Traverse_Result is
12355 Loc : constant Source_Ptr := Sloc (N);
12356
12357 procedure Add_Prefix (Ref : Node_Id; Comp : Entity_Id);
12358 -- Add the proper prefix to a reference to a component of the type
12359 -- when it is not already a selected component.
12360
12361 ----------------
12362 -- Add_Prefix --
12363 ----------------
12364
12365 procedure Add_Prefix (Ref : Node_Id; Comp : Entity_Id) is
12366 begin
12367 Rewrite (Ref,
12368 Make_Selected_Component (Loc,
12369 Prefix => New_Occurrence_Of (T, Loc),
12370 Selector_Name => New_Occurrence_Of (Comp, Loc)));
12371 Replace_Type_Reference (Prefix (Ref));
12372 end Add_Prefix;
12373
12374 -- Local variables
12375
12376 Comp : Entity_Id;
12377 Pref : Node_Id;
12378 Scop : Entity_Id;
12379
12380 -- Start of processing for Replace_Type_Ref
12381
12382 begin
12383 if Nkind (N) = N_Identifier then
12384
12385 -- If not the type name, check whether it is a reference to some
12386 -- other type, which must be frozen before the predicate function
12387 -- is analyzed, i.e. before the freeze node of the type to which
12388 -- the predicate applies.
12389
12390 if Chars (N) /= TName then
12391 if Present (Current_Entity (N))
12392 and then Is_Type (Current_Entity (N))
12393 then
12394 Freeze_Before (Freeze_Node (T), Current_Entity (N));
12395 end if;
12396
12397 -- The components of the type are directly visible and can
12398 -- be referenced without a prefix.
12399
12400 if Nkind (Parent (N)) = N_Selected_Component then
12401 null;
12402
12403 -- In expression C (I), C may be a directly visible function
12404 -- or a visible component that has an array type. Disambiguate
12405 -- by examining the component type.
12406
12407 elsif Nkind (Parent (N)) = N_Indexed_Component
12408 and then N = Prefix (Parent (N))
12409 then
12410 Comp := Visible_Component (Chars (N));
12411
12412 if Present (Comp) and then Is_Array_Type (Etype (Comp)) then
12413 Add_Prefix (N, Comp);
12414 end if;
12415
12416 else
12417 Comp := Visible_Component (Chars (N));
12418
12419 if Present (Comp) then
12420 Add_Prefix (N, Comp);
12421 end if;
12422 end if;
12423
12424 return Skip;
12425
12426 -- Otherwise do the replacement and we are done with this node
12427
12428 else
12429 Replace_Type_Reference (N);
12430 return Skip;
12431 end if;
12432
12433 -- Case of selected component (which is what a qualification looks
12434 -- like in the unanalyzed tree, which is what we have.
12435
12436 elsif Nkind (N) = N_Selected_Component then
12437
12438 -- If selector name is not our type, keeping going (we might still
12439 -- have an occurrence of the type in the prefix).
12440
12441 if Nkind (Selector_Name (N)) /= N_Identifier
12442 or else Chars (Selector_Name (N)) /= TName
12443 then
12444 return OK;
12445
12446 -- Selector name is our type, check qualification
12447
12448 else
12449 -- Loop through scopes and prefixes, doing comparison
12450
12451 Scop := Current_Scope;
12452 Pref := Prefix (N);
12453 loop
12454 -- Continue if no more scopes or scope with no name
12455
12456 if No (Scop) or else Nkind (Scop) not in N_Has_Chars then
12457 return OK;
12458 end if;
12459
12460 -- Do replace if prefix is an identifier matching the scope
12461 -- that we are currently looking at.
12462
12463 if Nkind (Pref) = N_Identifier
12464 and then Chars (Pref) = Chars (Scop)
12465 then
12466 Replace_Type_Reference (N);
12467 return Skip;
12468 end if;
12469
12470 -- Go check scope above us if prefix is itself of the form
12471 -- of a selected component, whose selector matches the scope
12472 -- we are currently looking at.
12473
12474 if Nkind (Pref) = N_Selected_Component
12475 and then Nkind (Selector_Name (Pref)) = N_Identifier
12476 and then Chars (Selector_Name (Pref)) = Chars (Scop)
12477 then
12478 Scop := Scope (Scop);
12479 Pref := Prefix (Pref);
12480
12481 -- For anything else, we don't have a match, so keep on
12482 -- going, there are still some weird cases where we may
12483 -- still have a replacement within the prefix.
12484
12485 else
12486 return OK;
12487 end if;
12488 end loop;
12489 end if;
12490
12491 -- Continue for any other node kind
12492
12493 else
12494 return OK;
12495 end if;
12496 end Replace_Type_Ref;
12497
12498 procedure Replace_Type_Refs is new Traverse_Proc (Replace_Type_Ref);
12499
12500 -----------------------
12501 -- Visible_Component --
12502 -----------------------
12503
12504 function Visible_Component (Comp : Name_Id) return Entity_Id is
12505 E : Entity_Id;
12506
12507 begin
12508 if Ekind (T) /= E_Record_Type then
12509 return Empty;
12510
12511 else
12512 E := First_Entity (T);
12513 while Present (E) loop
12514 if Comes_From_Source (E) and then Chars (E) = Comp then
12515 return E;
12516 end if;
12517
12518 Next_Entity (E);
12519 end loop;
12520
12521 return Empty;
12522 end if;
12523 end Visible_Component;
12524
12525 -- Start of processing for Replace_Type_References_Generic
12526
12527 begin
12528 Replace_Type_Refs (N);
12529 end Replace_Type_References_Generic;
12530
12531 --------------------------------
12532 -- Resolve_Aspect_Expressions --
12533 --------------------------------
12534
12535 procedure Resolve_Aspect_Expressions (E : Entity_Id) is
12536 ASN : Node_Id;
12537 A_Id : Aspect_Id;
12538 Expr : Node_Id;
12539
12540 function Resolve_Name (N : Node_Id) return Traverse_Result;
12541 -- Verify that all identifiers in the expression, with the exception
12542 -- of references to the current entity, denote visible entities. This
12543 -- is done only to detect visibility errors, as the expression will be
12544 -- properly analyzed/expanded during analysis of the predicate function
12545 -- body. We omit quantified expressions from this test, given that they
12546 -- introduce a local identifier that would require proper expansion to
12547 -- handle properly.
12548
12549 ------------------
12550 -- Resolve_Name --
12551 ------------------
12552
12553 function Resolve_Name (N : Node_Id) return Traverse_Result is
12554 begin
12555 if Nkind (N) = N_Selected_Component then
12556 if Nkind (Prefix (N)) = N_Identifier
12557 and then Chars (Prefix (N)) /= Chars (E)
12558 then
12559 Find_Selected_Component (N);
12560 end if;
12561
12562 return Skip;
12563
12564 elsif Nkind (N) = N_Identifier and then Chars (N) /= Chars (E) then
12565 Find_Direct_Name (N);
12566 Set_Entity (N, Empty);
12567
12568 elsif Nkind (N) = N_Quantified_Expression then
12569 return Skip;
12570 end if;
12571
12572 return OK;
12573 end Resolve_Name;
12574
12575 procedure Resolve_Aspect_Expression is new Traverse_Proc (Resolve_Name);
12576
12577 -- Start of processing for Resolve_Aspect_Expressions
12578
12579 begin
12580 ASN := First_Rep_Item (E);
12581 while Present (ASN) loop
12582 if Nkind (ASN) = N_Aspect_Specification and then Entity (ASN) = E then
12583 A_Id := Get_Aspect_Id (ASN);
12584 Expr := Expression (ASN);
12585
12586 case A_Id is
12587
12588 -- For now we only deal with aspects that do not generate
12589 -- subprograms, or that may mention current instances of
12590 -- types. These will require special handling (???TBD).
12591
12592 when Aspect_Predicate |
12593 Aspect_Predicate_Failure |
12594 Aspect_Invariant =>
12595 null;
12596
12597 when Aspect_Dynamic_Predicate |
12598 Aspect_Static_Predicate =>
12599
12600 -- Build predicate function specification and preanalyze
12601 -- expression after type replacement.
12602
12603 if No (Predicate_Function (E)) then
12604 declare
12605 FDecl : constant Node_Id :=
12606 Build_Predicate_Function_Declaration (E);
12607 pragma Unreferenced (FDecl);
12608 begin
12609 Resolve_Aspect_Expression (Expr);
12610 end;
12611 end if;
12612
12613 when Pre_Post_Aspects =>
12614 null;
12615
12616 when Aspect_Iterable =>
12617 if Nkind (Expr) = N_Aggregate then
12618 declare
12619 Assoc : Node_Id;
12620
12621 begin
12622 Assoc := First (Component_Associations (Expr));
12623 while Present (Assoc) loop
12624 Find_Direct_Name (Expression (Assoc));
12625 Next (Assoc);
12626 end loop;
12627 end;
12628 end if;
12629
12630 when others =>
12631 if Present (Expr) then
12632 case Aspect_Argument (A_Id) is
12633 when Expression | Optional_Expression =>
12634 Analyze_And_Resolve (Expression (ASN));
12635
12636 when Name | Optional_Name =>
12637 if Nkind (Expr) = N_Identifier then
12638 Find_Direct_Name (Expr);
12639
12640 elsif Nkind (Expr) = N_Selected_Component then
12641 Find_Selected_Component (Expr);
12642
12643 else
12644 null;
12645 end if;
12646 end case;
12647 end if;
12648 end case;
12649 end if;
12650
12651 ASN := Next_Rep_Item (ASN);
12652 end loop;
12653 end Resolve_Aspect_Expressions;
12654
12655 -------------------------
12656 -- Same_Representation --
12657 -------------------------
12658
12659 function Same_Representation (Typ1, Typ2 : Entity_Id) return Boolean is
12660 T1 : constant Entity_Id := Underlying_Type (Typ1);
12661 T2 : constant Entity_Id := Underlying_Type (Typ2);
12662
12663 begin
12664 -- A quick check, if base types are the same, then we definitely have
12665 -- the same representation, because the subtype specific representation
12666 -- attributes (Size and Alignment) do not affect representation from
12667 -- the point of view of this test.
12668
12669 if Base_Type (T1) = Base_Type (T2) then
12670 return True;
12671
12672 elsif Is_Private_Type (Base_Type (T2))
12673 and then Base_Type (T1) = Full_View (Base_Type (T2))
12674 then
12675 return True;
12676 end if;
12677
12678 -- Tagged types never have differing representations
12679
12680 if Is_Tagged_Type (T1) then
12681 return True;
12682 end if;
12683
12684 -- Representations are definitely different if conventions differ
12685
12686 if Convention (T1) /= Convention (T2) then
12687 return False;
12688 end if;
12689
12690 -- Representations are different if component alignments or scalar
12691 -- storage orders differ.
12692
12693 if (Is_Record_Type (T1) or else Is_Array_Type (T1))
12694 and then
12695 (Is_Record_Type (T2) or else Is_Array_Type (T2))
12696 and then
12697 (Component_Alignment (T1) /= Component_Alignment (T2)
12698 or else Reverse_Storage_Order (T1) /= Reverse_Storage_Order (T2))
12699 then
12700 return False;
12701 end if;
12702
12703 -- For arrays, the only real issue is component size. If we know the
12704 -- component size for both arrays, and it is the same, then that's
12705 -- good enough to know we don't have a change of representation.
12706
12707 if Is_Array_Type (T1) then
12708 if Known_Component_Size (T1)
12709 and then Known_Component_Size (T2)
12710 and then Component_Size (T1) = Component_Size (T2)
12711 then
12712 return True;
12713 end if;
12714 end if;
12715
12716 -- Types definitely have same representation if neither has non-standard
12717 -- representation since default representations are always consistent.
12718 -- If only one has non-standard representation, and the other does not,
12719 -- then we consider that they do not have the same representation. They
12720 -- might, but there is no way of telling early enough.
12721
12722 if Has_Non_Standard_Rep (T1) then
12723 if not Has_Non_Standard_Rep (T2) then
12724 return False;
12725 end if;
12726 else
12727 return not Has_Non_Standard_Rep (T2);
12728 end if;
12729
12730 -- Here the two types both have non-standard representation, and we need
12731 -- to determine if they have the same non-standard representation.
12732
12733 -- For arrays, we simply need to test if the component sizes are the
12734 -- same. Pragma Pack is reflected in modified component sizes, so this
12735 -- check also deals with pragma Pack.
12736
12737 if Is_Array_Type (T1) then
12738 return Component_Size (T1) = Component_Size (T2);
12739
12740 -- Tagged types always have the same representation, because it is not
12741 -- possible to specify different representations for common fields.
12742
12743 elsif Is_Tagged_Type (T1) then
12744 return True;
12745
12746 -- Case of record types
12747
12748 elsif Is_Record_Type (T1) then
12749
12750 -- Packed status must conform
12751
12752 if Is_Packed (T1) /= Is_Packed (T2) then
12753 return False;
12754
12755 -- Otherwise we must check components. Typ2 maybe a constrained
12756 -- subtype with fewer components, so we compare the components
12757 -- of the base types.
12758
12759 else
12760 Record_Case : declare
12761 CD1, CD2 : Entity_Id;
12762
12763 function Same_Rep return Boolean;
12764 -- CD1 and CD2 are either components or discriminants. This
12765 -- function tests whether they have the same representation.
12766
12767 --------------
12768 -- Same_Rep --
12769 --------------
12770
12771 function Same_Rep return Boolean is
12772 begin
12773 if No (Component_Clause (CD1)) then
12774 return No (Component_Clause (CD2));
12775 else
12776 -- Note: at this point, component clauses have been
12777 -- normalized to the default bit order, so that the
12778 -- comparison of Component_Bit_Offsets is meaningful.
12779
12780 return
12781 Present (Component_Clause (CD2))
12782 and then
12783 Component_Bit_Offset (CD1) = Component_Bit_Offset (CD2)
12784 and then
12785 Esize (CD1) = Esize (CD2);
12786 end if;
12787 end Same_Rep;
12788
12789 -- Start of processing for Record_Case
12790
12791 begin
12792 if Has_Discriminants (T1) then
12793
12794 -- The number of discriminants may be different if the
12795 -- derived type has fewer (constrained by values). The
12796 -- invisible discriminants retain the representation of
12797 -- the original, so the discrepancy does not per se
12798 -- indicate a different representation.
12799
12800 CD1 := First_Discriminant (T1);
12801 CD2 := First_Discriminant (T2);
12802 while Present (CD1) and then Present (CD2) loop
12803 if not Same_Rep then
12804 return False;
12805 else
12806 Next_Discriminant (CD1);
12807 Next_Discriminant (CD2);
12808 end if;
12809 end loop;
12810 end if;
12811
12812 CD1 := First_Component (Underlying_Type (Base_Type (T1)));
12813 CD2 := First_Component (Underlying_Type (Base_Type (T2)));
12814 while Present (CD1) loop
12815 if not Same_Rep then
12816 return False;
12817 else
12818 Next_Component (CD1);
12819 Next_Component (CD2);
12820 end if;
12821 end loop;
12822
12823 return True;
12824 end Record_Case;
12825 end if;
12826
12827 -- For enumeration types, we must check each literal to see if the
12828 -- representation is the same. Note that we do not permit enumeration
12829 -- representation clauses for Character and Wide_Character, so these
12830 -- cases were already dealt with.
12831
12832 elsif Is_Enumeration_Type (T1) then
12833 Enumeration_Case : declare
12834 L1, L2 : Entity_Id;
12835
12836 begin
12837 L1 := First_Literal (T1);
12838 L2 := First_Literal (T2);
12839 while Present (L1) loop
12840 if Enumeration_Rep (L1) /= Enumeration_Rep (L2) then
12841 return False;
12842 else
12843 Next_Literal (L1);
12844 Next_Literal (L2);
12845 end if;
12846 end loop;
12847
12848 return True;
12849 end Enumeration_Case;
12850
12851 -- Any other types have the same representation for these purposes
12852
12853 else
12854 return True;
12855 end if;
12856 end Same_Representation;
12857
12858 --------------------------------
12859 -- Resolve_Iterable_Operation --
12860 --------------------------------
12861
12862 procedure Resolve_Iterable_Operation
12863 (N : Node_Id;
12864 Cursor : Entity_Id;
12865 Typ : Entity_Id;
12866 Nam : Name_Id)
12867 is
12868 Ent : Entity_Id;
12869 F1 : Entity_Id;
12870 F2 : Entity_Id;
12871
12872 begin
12873 if not Is_Overloaded (N) then
12874 if not Is_Entity_Name (N)
12875 or else Ekind (Entity (N)) /= E_Function
12876 or else Scope (Entity (N)) /= Scope (Typ)
12877 or else No (First_Formal (Entity (N)))
12878 or else Etype (First_Formal (Entity (N))) /= Typ
12879 then
12880 Error_Msg_N ("iterable primitive must be local function name "
12881 & "whose first formal is an iterable type", N);
12882 return;
12883 end if;
12884
12885 Ent := Entity (N);
12886 F1 := First_Formal (Ent);
12887 if Nam = Name_First then
12888
12889 -- First (Container) => Cursor
12890
12891 if Etype (Ent) /= Cursor then
12892 Error_Msg_N ("primitive for First must yield a curosr", N);
12893 end if;
12894
12895 elsif Nam = Name_Next then
12896
12897 -- Next (Container, Cursor) => Cursor
12898
12899 F2 := Next_Formal (F1);
12900
12901 if Etype (F2) /= Cursor
12902 or else Etype (Ent) /= Cursor
12903 or else Present (Next_Formal (F2))
12904 then
12905 Error_Msg_N ("no match for Next iterable primitive", N);
12906 end if;
12907
12908 elsif Nam = Name_Has_Element then
12909
12910 -- Has_Element (Container, Cursor) => Boolean
12911
12912 F2 := Next_Formal (F1);
12913 if Etype (F2) /= Cursor
12914 or else Etype (Ent) /= Standard_Boolean
12915 or else Present (Next_Formal (F2))
12916 then
12917 Error_Msg_N ("no match for Has_Element iterable primitive", N);
12918 end if;
12919
12920 elsif Nam = Name_Element then
12921 F2 := Next_Formal (F1);
12922
12923 if No (F2)
12924 or else Etype (F2) /= Cursor
12925 or else Present (Next_Formal (F2))
12926 then
12927 Error_Msg_N ("no match for Element iterable primitive", N);
12928 end if;
12929 null;
12930
12931 else
12932 raise Program_Error;
12933 end if;
12934
12935 else
12936 -- Overloaded case: find subprogram with proper signature.
12937 -- Caller will report error if no match is found.
12938
12939 declare
12940 I : Interp_Index;
12941 It : Interp;
12942
12943 begin
12944 Get_First_Interp (N, I, It);
12945 while Present (It.Typ) loop
12946 if Ekind (It.Nam) = E_Function
12947 and then Scope (It.Nam) = Scope (Typ)
12948 and then Etype (First_Formal (It.Nam)) = Typ
12949 then
12950 F1 := First_Formal (It.Nam);
12951
12952 if Nam = Name_First then
12953 if Etype (It.Nam) = Cursor
12954 and then No (Next_Formal (F1))
12955 then
12956 Set_Entity (N, It.Nam);
12957 exit;
12958 end if;
12959
12960 elsif Nam = Name_Next then
12961 F2 := Next_Formal (F1);
12962
12963 if Present (F2)
12964 and then No (Next_Formal (F2))
12965 and then Etype (F2) = Cursor
12966 and then Etype (It.Nam) = Cursor
12967 then
12968 Set_Entity (N, It.Nam);
12969 exit;
12970 end if;
12971
12972 elsif Nam = Name_Has_Element then
12973 F2 := Next_Formal (F1);
12974
12975 if Present (F2)
12976 and then No (Next_Formal (F2))
12977 and then Etype (F2) = Cursor
12978 and then Etype (It.Nam) = Standard_Boolean
12979 then
12980 Set_Entity (N, It.Nam);
12981 F2 := Next_Formal (F1);
12982 exit;
12983 end if;
12984
12985 elsif Nam = Name_Element then
12986 F2 := Next_Formal (F1);
12987
12988 if Present (F2)
12989 and then No (Next_Formal (F2))
12990 and then Etype (F2) = Cursor
12991 then
12992 Set_Entity (N, It.Nam);
12993 exit;
12994 end if;
12995 end if;
12996 end if;
12997
12998 Get_Next_Interp (I, It);
12999 end loop;
13000 end;
13001 end if;
13002 end Resolve_Iterable_Operation;
13003
13004 ----------------
13005 -- Set_Biased --
13006 ----------------
13007
13008 procedure Set_Biased
13009 (E : Entity_Id;
13010 N : Node_Id;
13011 Msg : String;
13012 Biased : Boolean := True)
13013 is
13014 begin
13015 if Biased then
13016 Set_Has_Biased_Representation (E);
13017
13018 if Warn_On_Biased_Representation then
13019 Error_Msg_NE
13020 ("?B?" & Msg & " forces biased representation for&", N, E);
13021 end if;
13022 end if;
13023 end Set_Biased;
13024
13025 --------------------
13026 -- Set_Enum_Esize --
13027 --------------------
13028
13029 procedure Set_Enum_Esize (T : Entity_Id) is
13030 Lo : Uint;
13031 Hi : Uint;
13032 Sz : Nat;
13033
13034 begin
13035 Init_Alignment (T);
13036
13037 -- Find the minimum standard size (8,16,32,64) that fits
13038
13039 Lo := Enumeration_Rep (Entity (Type_Low_Bound (T)));
13040 Hi := Enumeration_Rep (Entity (Type_High_Bound (T)));
13041
13042 if Lo < 0 then
13043 if Lo >= -Uint_2**07 and then Hi < Uint_2**07 then
13044 Sz := Standard_Character_Size; -- May be > 8 on some targets
13045
13046 elsif Lo >= -Uint_2**15 and then Hi < Uint_2**15 then
13047 Sz := 16;
13048
13049 elsif Lo >= -Uint_2**31 and then Hi < Uint_2**31 then
13050 Sz := 32;
13051
13052 else pragma Assert (Lo >= -Uint_2**63 and then Hi < Uint_2**63);
13053 Sz := 64;
13054 end if;
13055
13056 else
13057 if Hi < Uint_2**08 then
13058 Sz := Standard_Character_Size; -- May be > 8 on some targets
13059
13060 elsif Hi < Uint_2**16 then
13061 Sz := 16;
13062
13063 elsif Hi < Uint_2**32 then
13064 Sz := 32;
13065
13066 else pragma Assert (Hi < Uint_2**63);
13067 Sz := 64;
13068 end if;
13069 end if;
13070
13071 -- That minimum is the proper size unless we have a foreign convention
13072 -- and the size required is 32 or less, in which case we bump the size
13073 -- up to 32. This is required for C and C++ and seems reasonable for
13074 -- all other foreign conventions.
13075
13076 if Has_Foreign_Convention (T)
13077 and then Esize (T) < Standard_Integer_Size
13078
13079 -- Don't do this if Short_Enums on target
13080
13081 and then not Target_Short_Enums
13082 then
13083 Init_Esize (T, Standard_Integer_Size);
13084 else
13085 Init_Esize (T, Sz);
13086 end if;
13087 end Set_Enum_Esize;
13088
13089 -----------------------------
13090 -- Uninstall_Discriminants --
13091 -----------------------------
13092
13093 procedure Uninstall_Discriminants (E : Entity_Id) is
13094 Disc : Entity_Id;
13095 Prev : Entity_Id;
13096 Outer : Entity_Id;
13097
13098 begin
13099 -- Discriminants have been made visible for type declarations and
13100 -- protected type declarations, not for subtype declarations.
13101
13102 if Nkind (Parent (E)) /= N_Subtype_Declaration then
13103 Disc := First_Discriminant (E);
13104 while Present (Disc) loop
13105 if Disc /= Current_Entity (Disc) then
13106 Prev := Current_Entity (Disc);
13107 while Present (Prev)
13108 and then Present (Homonym (Prev))
13109 and then Homonym (Prev) /= Disc
13110 loop
13111 Prev := Homonym (Prev);
13112 end loop;
13113 else
13114 Prev := Empty;
13115 end if;
13116
13117 Set_Is_Immediately_Visible (Disc, False);
13118
13119 Outer := Homonym (Disc);
13120 while Present (Outer) and then Scope (Outer) = E loop
13121 Outer := Homonym (Outer);
13122 end loop;
13123
13124 -- Reset homonym link of other entities, but do not modify link
13125 -- between entities in current scope, so that the back end can
13126 -- have a proper count of local overloadings.
13127
13128 if No (Prev) then
13129 Set_Name_Entity_Id (Chars (Disc), Outer);
13130
13131 elsif Scope (Prev) /= Scope (Disc) then
13132 Set_Homonym (Prev, Outer);
13133 end if;
13134
13135 Next_Discriminant (Disc);
13136 end loop;
13137 end if;
13138 end Uninstall_Discriminants;
13139
13140 -------------------------------------------
13141 -- Uninstall_Discriminants_And_Pop_Scope --
13142 -------------------------------------------
13143
13144 procedure Uninstall_Discriminants_And_Pop_Scope (E : Entity_Id) is
13145 begin
13146 if Has_Discriminants (E) then
13147 Uninstall_Discriminants (E);
13148 Pop_Scope;
13149 end if;
13150 end Uninstall_Discriminants_And_Pop_Scope;
13151
13152 ------------------------------
13153 -- Validate_Address_Clauses --
13154 ------------------------------
13155
13156 procedure Validate_Address_Clauses is
13157 function Offset_Value (Expr : Node_Id) return Uint;
13158 -- Given an Address attribute reference, return the value in bits of its
13159 -- offset from the first bit of the underlying entity, or 0 if it is not
13160 -- known at compile time.
13161
13162 ------------------
13163 -- Offset_Value --
13164 ------------------
13165
13166 function Offset_Value (Expr : Node_Id) return Uint is
13167 N : Node_Id := Prefix (Expr);
13168 Off : Uint;
13169 Val : Uint := Uint_0;
13170
13171 begin
13172 -- Climb the prefix chain and compute the cumulative offset
13173
13174 loop
13175 if Is_Entity_Name (N) then
13176 return Val;
13177
13178 elsif Nkind (N) = N_Selected_Component then
13179 Off := Component_Bit_Offset (Entity (Selector_Name (N)));
13180 if Off /= No_Uint and then Off >= Uint_0 then
13181 Val := Val + Off;
13182 N := Prefix (N);
13183 else
13184 return Uint_0;
13185 end if;
13186
13187 elsif Nkind (N) = N_Indexed_Component then
13188 Off := Indexed_Component_Bit_Offset (N);
13189 if Off /= No_Uint then
13190 Val := Val + Off;
13191 N := Prefix (N);
13192 else
13193 return Uint_0;
13194 end if;
13195
13196 else
13197 return Uint_0;
13198 end if;
13199 end loop;
13200 end Offset_Value;
13201
13202 -- Start of processing for Validate_Address_Clauses
13203
13204 begin
13205 for J in Address_Clause_Checks.First .. Address_Clause_Checks.Last loop
13206 declare
13207 ACCR : Address_Clause_Check_Record
13208 renames Address_Clause_Checks.Table (J);
13209
13210 Expr : Node_Id;
13211
13212 X_Alignment : Uint;
13213 Y_Alignment : Uint;
13214
13215 X_Size : Uint;
13216 Y_Size : Uint;
13217
13218 X_Offs : Uint;
13219
13220 begin
13221 -- Skip processing of this entry if warning already posted
13222
13223 if not Address_Warning_Posted (ACCR.N) then
13224 Expr := Original_Node (Expression (ACCR.N));
13225
13226 -- Get alignments, sizes and offset, if any
13227
13228 X_Alignment := Alignment (ACCR.X);
13229 X_Size := Esize (ACCR.X);
13230
13231 if Present (ACCR.Y) then
13232 Y_Alignment := Alignment (ACCR.Y);
13233 Y_Size := Esize (ACCR.Y);
13234 end if;
13235
13236 if ACCR.Off
13237 and then Nkind (Expr) = N_Attribute_Reference
13238 and then Attribute_Name (Expr) = Name_Address
13239 then
13240 X_Offs := Offset_Value (Expr);
13241 else
13242 X_Offs := Uint_0;
13243 end if;
13244
13245 -- Check for known value not multiple of alignment
13246
13247 if No (ACCR.Y) then
13248 if not Alignment_Checks_Suppressed (ACCR.X)
13249 and then X_Alignment /= 0
13250 and then ACCR.A mod X_Alignment /= 0
13251 then
13252 Error_Msg_NE
13253 ("??specified address for& is inconsistent with "
13254 & "alignment", ACCR.N, ACCR.X);
13255 Error_Msg_N
13256 ("\??program execution may be erroneous (RM 13.3(27))",
13257 ACCR.N);
13258
13259 Error_Msg_Uint_1 := X_Alignment;
13260 Error_Msg_NE ("\??alignment of & is ^", ACCR.N, ACCR.X);
13261 end if;
13262
13263 -- Check for large object overlaying smaller one
13264
13265 elsif Y_Size > Uint_0
13266 and then X_Size > Uint_0
13267 and then X_Offs + X_Size > Y_Size
13268 then
13269 Error_Msg_NE ("??& overlays smaller object", ACCR.N, ACCR.X);
13270 Error_Msg_N
13271 ("\??program execution may be erroneous", ACCR.N);
13272
13273 Error_Msg_Uint_1 := X_Size;
13274 Error_Msg_NE ("\??size of & is ^", ACCR.N, ACCR.X);
13275
13276 Error_Msg_Uint_1 := Y_Size;
13277 Error_Msg_NE ("\??size of & is ^", ACCR.N, ACCR.Y);
13278
13279 if Y_Size >= X_Size then
13280 Error_Msg_Uint_1 := X_Offs;
13281 Error_Msg_NE ("\??but offset of & is ^", ACCR.N, ACCR.X);
13282 end if;
13283
13284 -- Check for inadequate alignment, both of the base object
13285 -- and of the offset, if any. We only do this check if the
13286 -- run-time Alignment_Check is active. No point in warning
13287 -- if this check has been suppressed (or is suppressed by
13288 -- default in the non-strict alignment machine case).
13289
13290 -- Note: we do not check the alignment if we gave a size
13291 -- warning, since it would likely be redundant.
13292
13293 elsif not Alignment_Checks_Suppressed (ACCR.X)
13294 and then Y_Alignment /= Uint_0
13295 and then
13296 (Y_Alignment < X_Alignment
13297 or else
13298 (ACCR.Off
13299 and then Nkind (Expr) = N_Attribute_Reference
13300 and then Attribute_Name (Expr) = Name_Address
13301 and then Has_Compatible_Alignment
13302 (ACCR.X, Prefix (Expr), True) /=
13303 Known_Compatible))
13304 then
13305 Error_Msg_NE
13306 ("??specified address for& may be inconsistent with "
13307 & "alignment", ACCR.N, ACCR.X);
13308 Error_Msg_N
13309 ("\??program execution may be erroneous (RM 13.3(27))",
13310 ACCR.N);
13311
13312 Error_Msg_Uint_1 := X_Alignment;
13313 Error_Msg_NE ("\??alignment of & is ^", ACCR.N, ACCR.X);
13314
13315 Error_Msg_Uint_1 := Y_Alignment;
13316 Error_Msg_NE ("\??alignment of & is ^", ACCR.N, ACCR.Y);
13317
13318 if Y_Alignment >= X_Alignment then
13319 Error_Msg_N
13320 ("\??but offset is not multiple of alignment", ACCR.N);
13321 end if;
13322 end if;
13323 end if;
13324 end;
13325 end loop;
13326 end Validate_Address_Clauses;
13327
13328 ---------------------------
13329 -- Validate_Independence --
13330 ---------------------------
13331
13332 procedure Validate_Independence is
13333 SU : constant Uint := UI_From_Int (System_Storage_Unit);
13334 N : Node_Id;
13335 E : Entity_Id;
13336 IC : Boolean;
13337 Comp : Entity_Id;
13338 Addr : Node_Id;
13339 P : Node_Id;
13340
13341 procedure Check_Array_Type (Atyp : Entity_Id);
13342 -- Checks if the array type Atyp has independent components, and
13343 -- if not, outputs an appropriate set of error messages.
13344
13345 procedure No_Independence;
13346 -- Output message that independence cannot be guaranteed
13347
13348 function OK_Component (C : Entity_Id) return Boolean;
13349 -- Checks one component to see if it is independently accessible, and
13350 -- if so yields True, otherwise yields False if independent access
13351 -- cannot be guaranteed. This is a conservative routine, it only
13352 -- returns True if it knows for sure, it returns False if it knows
13353 -- there is a problem, or it cannot be sure there is no problem.
13354
13355 procedure Reason_Bad_Component (C : Entity_Id);
13356 -- Outputs continuation message if a reason can be determined for
13357 -- the component C being bad.
13358
13359 ----------------------
13360 -- Check_Array_Type --
13361 ----------------------
13362
13363 procedure Check_Array_Type (Atyp : Entity_Id) is
13364 Ctyp : constant Entity_Id := Component_Type (Atyp);
13365
13366 begin
13367 -- OK if no alignment clause, no pack, and no component size
13368
13369 if not Has_Component_Size_Clause (Atyp)
13370 and then not Has_Alignment_Clause (Atyp)
13371 and then not Is_Packed (Atyp)
13372 then
13373 return;
13374 end if;
13375
13376 -- Case of component size is greater than or equal to 64 and the
13377 -- alignment of the array is at least as large as the alignment
13378 -- of the component. We are definitely OK in this situation.
13379
13380 if Known_Component_Size (Atyp)
13381 and then Component_Size (Atyp) >= 64
13382 and then Known_Alignment (Atyp)
13383 and then Known_Alignment (Ctyp)
13384 and then Alignment (Atyp) >= Alignment (Ctyp)
13385 then
13386 return;
13387 end if;
13388
13389 -- Check actual component size
13390
13391 if not Known_Component_Size (Atyp)
13392 or else not (Addressable (Component_Size (Atyp))
13393 and then Component_Size (Atyp) < 64)
13394 or else Component_Size (Atyp) mod Esize (Ctyp) /= 0
13395 then
13396 No_Independence;
13397
13398 -- Bad component size, check reason
13399
13400 if Has_Component_Size_Clause (Atyp) then
13401 P := Get_Attribute_Definition_Clause
13402 (Atyp, Attribute_Component_Size);
13403
13404 if Present (P) then
13405 Error_Msg_Sloc := Sloc (P);
13406 Error_Msg_N ("\because of Component_Size clause#", N);
13407 return;
13408 end if;
13409 end if;
13410
13411 if Is_Packed (Atyp) then
13412 P := Get_Rep_Pragma (Atyp, Name_Pack);
13413
13414 if Present (P) then
13415 Error_Msg_Sloc := Sloc (P);
13416 Error_Msg_N ("\because of pragma Pack#", N);
13417 return;
13418 end if;
13419 end if;
13420
13421 -- No reason found, just return
13422
13423 return;
13424 end if;
13425
13426 -- Array type is OK independence-wise
13427
13428 return;
13429 end Check_Array_Type;
13430
13431 ---------------------
13432 -- No_Independence --
13433 ---------------------
13434
13435 procedure No_Independence is
13436 begin
13437 if Pragma_Name (N) = Name_Independent then
13438 Error_Msg_NE ("independence cannot be guaranteed for&", N, E);
13439 else
13440 Error_Msg_NE
13441 ("independent components cannot be guaranteed for&", N, E);
13442 end if;
13443 end No_Independence;
13444
13445 ------------------
13446 -- OK_Component --
13447 ------------------
13448
13449 function OK_Component (C : Entity_Id) return Boolean is
13450 Rec : constant Entity_Id := Scope (C);
13451 Ctyp : constant Entity_Id := Etype (C);
13452
13453 begin
13454 -- OK if no component clause, no Pack, and no alignment clause
13455
13456 if No (Component_Clause (C))
13457 and then not Is_Packed (Rec)
13458 and then not Has_Alignment_Clause (Rec)
13459 then
13460 return True;
13461 end if;
13462
13463 -- Here we look at the actual component layout. A component is
13464 -- addressable if its size is a multiple of the Esize of the
13465 -- component type, and its starting position in the record has
13466 -- appropriate alignment, and the record itself has appropriate
13467 -- alignment to guarantee the component alignment.
13468
13469 -- Make sure sizes are static, always assume the worst for any
13470 -- cases where we cannot check static values.
13471
13472 if not (Known_Static_Esize (C)
13473 and then
13474 Known_Static_Esize (Ctyp))
13475 then
13476 return False;
13477 end if;
13478
13479 -- Size of component must be addressable or greater than 64 bits
13480 -- and a multiple of bytes.
13481
13482 if not Addressable (Esize (C)) and then Esize (C) < Uint_64 then
13483 return False;
13484 end if;
13485
13486 -- Check size is proper multiple
13487
13488 if Esize (C) mod Esize (Ctyp) /= 0 then
13489 return False;
13490 end if;
13491
13492 -- Check alignment of component is OK
13493
13494 if not Known_Component_Bit_Offset (C)
13495 or else Component_Bit_Offset (C) < Uint_0
13496 or else Component_Bit_Offset (C) mod Esize (Ctyp) /= 0
13497 then
13498 return False;
13499 end if;
13500
13501 -- Check alignment of record type is OK
13502
13503 if not Known_Alignment (Rec)
13504 or else (Alignment (Rec) * SU) mod Esize (Ctyp) /= 0
13505 then
13506 return False;
13507 end if;
13508
13509 -- All tests passed, component is addressable
13510
13511 return True;
13512 end OK_Component;
13513
13514 --------------------------
13515 -- Reason_Bad_Component --
13516 --------------------------
13517
13518 procedure Reason_Bad_Component (C : Entity_Id) is
13519 Rec : constant Entity_Id := Scope (C);
13520 Ctyp : constant Entity_Id := Etype (C);
13521
13522 begin
13523 -- If component clause present assume that's the problem
13524
13525 if Present (Component_Clause (C)) then
13526 Error_Msg_Sloc := Sloc (Component_Clause (C));
13527 Error_Msg_N ("\because of Component_Clause#", N);
13528 return;
13529 end if;
13530
13531 -- If pragma Pack clause present, assume that's the problem
13532
13533 if Is_Packed (Rec) then
13534 P := Get_Rep_Pragma (Rec, Name_Pack);
13535
13536 if Present (P) then
13537 Error_Msg_Sloc := Sloc (P);
13538 Error_Msg_N ("\because of pragma Pack#", N);
13539 return;
13540 end if;
13541 end if;
13542
13543 -- See if record has bad alignment clause
13544
13545 if Has_Alignment_Clause (Rec)
13546 and then Known_Alignment (Rec)
13547 and then (Alignment (Rec) * SU) mod Esize (Ctyp) /= 0
13548 then
13549 P := Get_Attribute_Definition_Clause (Rec, Attribute_Alignment);
13550
13551 if Present (P) then
13552 Error_Msg_Sloc := Sloc (P);
13553 Error_Msg_N ("\because of Alignment clause#", N);
13554 end if;
13555 end if;
13556
13557 -- Couldn't find a reason, so return without a message
13558
13559 return;
13560 end Reason_Bad_Component;
13561
13562 -- Start of processing for Validate_Independence
13563
13564 begin
13565 for J in Independence_Checks.First .. Independence_Checks.Last loop
13566 N := Independence_Checks.Table (J).N;
13567 E := Independence_Checks.Table (J).E;
13568 IC := Pragma_Name (N) = Name_Independent_Components;
13569
13570 -- Deal with component case
13571
13572 if Ekind (E) = E_Discriminant or else Ekind (E) = E_Component then
13573 if not OK_Component (E) then
13574 No_Independence;
13575 Reason_Bad_Component (E);
13576 goto Continue;
13577 end if;
13578 end if;
13579
13580 -- Deal with record with Independent_Components
13581
13582 if IC and then Is_Record_Type (E) then
13583 Comp := First_Component_Or_Discriminant (E);
13584 while Present (Comp) loop
13585 if not OK_Component (Comp) then
13586 No_Independence;
13587 Reason_Bad_Component (Comp);
13588 goto Continue;
13589 end if;
13590
13591 Next_Component_Or_Discriminant (Comp);
13592 end loop;
13593 end if;
13594
13595 -- Deal with address clause case
13596
13597 if Is_Object (E) then
13598 Addr := Address_Clause (E);
13599
13600 if Present (Addr) then
13601 No_Independence;
13602 Error_Msg_Sloc := Sloc (Addr);
13603 Error_Msg_N ("\because of Address clause#", N);
13604 goto Continue;
13605 end if;
13606 end if;
13607
13608 -- Deal with independent components for array type
13609
13610 if IC and then Is_Array_Type (E) then
13611 Check_Array_Type (E);
13612 end if;
13613
13614 -- Deal with independent components for array object
13615
13616 if IC and then Is_Object (E) and then Is_Array_Type (Etype (E)) then
13617 Check_Array_Type (Etype (E));
13618 end if;
13619
13620 <<Continue>> null;
13621 end loop;
13622 end Validate_Independence;
13623
13624 ------------------------------
13625 -- Validate_Iterable_Aspect --
13626 ------------------------------
13627
13628 procedure Validate_Iterable_Aspect (Typ : Entity_Id; ASN : Node_Id) is
13629 Assoc : Node_Id;
13630 Expr : Node_Id;
13631
13632 Prim : Node_Id;
13633 Cursor : constant Entity_Id := Get_Cursor_Type (ASN, Typ);
13634
13635 First_Id : Entity_Id;
13636 Next_Id : Entity_Id;
13637 Has_Element_Id : Entity_Id;
13638 Element_Id : Entity_Id;
13639
13640 begin
13641 -- If previous error aspect is unusable
13642
13643 if Cursor = Any_Type then
13644 return;
13645 end if;
13646
13647 First_Id := Empty;
13648 Next_Id := Empty;
13649 Has_Element_Id := Empty;
13650 Element_Id := Empty;
13651
13652 -- Each expression must resolve to a function with the proper signature
13653
13654 Assoc := First (Component_Associations (Expression (ASN)));
13655 while Present (Assoc) loop
13656 Expr := Expression (Assoc);
13657 Analyze (Expr);
13658
13659 Prim := First (Choices (Assoc));
13660
13661 if Nkind (Prim) /= N_Identifier or else Present (Next (Prim)) then
13662 Error_Msg_N ("illegal name in association", Prim);
13663
13664 elsif Chars (Prim) = Name_First then
13665 Resolve_Iterable_Operation (Expr, Cursor, Typ, Name_First);
13666 First_Id := Entity (Expr);
13667
13668 elsif Chars (Prim) = Name_Next then
13669 Resolve_Iterable_Operation (Expr, Cursor, Typ, Name_Next);
13670 Next_Id := Entity (Expr);
13671
13672 elsif Chars (Prim) = Name_Has_Element then
13673 Resolve_Iterable_Operation (Expr, Cursor, Typ, Name_Has_Element);
13674 Has_Element_Id := Entity (Expr);
13675
13676 elsif Chars (Prim) = Name_Element then
13677 Resolve_Iterable_Operation (Expr, Cursor, Typ, Name_Element);
13678 Element_Id := Entity (Expr);
13679
13680 else
13681 Error_Msg_N ("invalid name for iterable function", Prim);
13682 end if;
13683
13684 Next (Assoc);
13685 end loop;
13686
13687 if No (First_Id) then
13688 Error_Msg_N ("match for First primitive not found", ASN);
13689
13690 elsif No (Next_Id) then
13691 Error_Msg_N ("match for Next primitive not found", ASN);
13692
13693 elsif No (Has_Element_Id) then
13694 Error_Msg_N ("match for Has_Element primitive not found", ASN);
13695
13696 elsif No (Element_Id) then
13697 null; -- Optional.
13698 end if;
13699 end Validate_Iterable_Aspect;
13700
13701 -----------------------------------
13702 -- Validate_Unchecked_Conversion --
13703 -----------------------------------
13704
13705 procedure Validate_Unchecked_Conversion
13706 (N : Node_Id;
13707 Act_Unit : Entity_Id)
13708 is
13709 Source : Entity_Id;
13710 Target : Entity_Id;
13711 Vnode : Node_Id;
13712
13713 begin
13714 -- Obtain source and target types. Note that we call Ancestor_Subtype
13715 -- here because the processing for generic instantiation always makes
13716 -- subtypes, and we want the original frozen actual types.
13717
13718 -- If we are dealing with private types, then do the check on their
13719 -- fully declared counterparts if the full declarations have been
13720 -- encountered (they don't have to be visible, but they must exist).
13721
13722 Source := Ancestor_Subtype (Etype (First_Formal (Act_Unit)));
13723
13724 if Is_Private_Type (Source)
13725 and then Present (Underlying_Type (Source))
13726 then
13727 Source := Underlying_Type (Source);
13728 end if;
13729
13730 Target := Ancestor_Subtype (Etype (Act_Unit));
13731
13732 -- If either type is generic, the instantiation happens within a generic
13733 -- unit, and there is nothing to check. The proper check will happen
13734 -- when the enclosing generic is instantiated.
13735
13736 if Is_Generic_Type (Source) or else Is_Generic_Type (Target) then
13737 return;
13738 end if;
13739
13740 if Is_Private_Type (Target)
13741 and then Present (Underlying_Type (Target))
13742 then
13743 Target := Underlying_Type (Target);
13744 end if;
13745
13746 -- Source may be unconstrained array, but not target, except in relaxed
13747 -- semantics mode.
13748
13749 if Is_Array_Type (Target)
13750 and then not Is_Constrained (Target)
13751 and then not Relaxed_RM_Semantics
13752 then
13753 Error_Msg_N
13754 ("unchecked conversion to unconstrained array not allowed", N);
13755 return;
13756 end if;
13757
13758 -- Warn if conversion between two different convention pointers
13759
13760 if Is_Access_Type (Target)
13761 and then Is_Access_Type (Source)
13762 and then Convention (Target) /= Convention (Source)
13763 and then Warn_On_Unchecked_Conversion
13764 then
13765 -- Give warnings for subprogram pointers only on most targets
13766
13767 if Is_Access_Subprogram_Type (Target)
13768 or else Is_Access_Subprogram_Type (Source)
13769 then
13770 Error_Msg_N
13771 ("?z?conversion between pointers with different conventions!",
13772 N);
13773 end if;
13774 end if;
13775
13776 -- Warn if one of the operands is Ada.Calendar.Time. Do not emit a
13777 -- warning when compiling GNAT-related sources.
13778
13779 if Warn_On_Unchecked_Conversion
13780 and then not In_Predefined_Unit (N)
13781 and then RTU_Loaded (Ada_Calendar)
13782 and then (Chars (Source) = Name_Time
13783 or else
13784 Chars (Target) = Name_Time)
13785 then
13786 -- If Ada.Calendar is loaded and the name of one of the operands is
13787 -- Time, there is a good chance that this is Ada.Calendar.Time.
13788
13789 declare
13790 Calendar_Time : constant Entity_Id := Full_View (RTE (RO_CA_Time));
13791 begin
13792 pragma Assert (Present (Calendar_Time));
13793
13794 if Source = Calendar_Time or else Target = Calendar_Time then
13795 Error_Msg_N
13796 ("?z?representation of 'Time values may change between "
13797 & "'G'N'A'T versions", N);
13798 end if;
13799 end;
13800 end if;
13801
13802 -- Make entry in unchecked conversion table for later processing by
13803 -- Validate_Unchecked_Conversions, which will check sizes and alignments
13804 -- (using values set by the back end where possible). This is only done
13805 -- if the appropriate warning is active.
13806
13807 if Warn_On_Unchecked_Conversion then
13808 Unchecked_Conversions.Append
13809 (New_Val => UC_Entry'(Eloc => Sloc (N),
13810 Source => Source,
13811 Target => Target,
13812 Act_Unit => Act_Unit));
13813
13814 -- If both sizes are known statically now, then back-end annotation
13815 -- is not required to do a proper check but if either size is not
13816 -- known statically, then we need the annotation.
13817
13818 if Known_Static_RM_Size (Source)
13819 and then
13820 Known_Static_RM_Size (Target)
13821 then
13822 null;
13823 else
13824 Back_Annotate_Rep_Info := True;
13825 end if;
13826 end if;
13827
13828 -- If unchecked conversion to access type, and access type is declared
13829 -- in the same unit as the unchecked conversion, then set the flag
13830 -- No_Strict_Aliasing (no strict aliasing is implicit here)
13831
13832 if Is_Access_Type (Target) and then
13833 In_Same_Source_Unit (Target, N)
13834 then
13835 Set_No_Strict_Aliasing (Implementation_Base_Type (Target));
13836 end if;
13837
13838 -- Generate N_Validate_Unchecked_Conversion node for back end in case
13839 -- the back end needs to perform special validation checks.
13840
13841 -- Shouldn't this be in Exp_Ch13, since the check only gets done if we
13842 -- have full expansion and the back end is called ???
13843
13844 Vnode :=
13845 Make_Validate_Unchecked_Conversion (Sloc (N));
13846 Set_Source_Type (Vnode, Source);
13847 Set_Target_Type (Vnode, Target);
13848
13849 -- If the unchecked conversion node is in a list, just insert before it.
13850 -- If not we have some strange case, not worth bothering about.
13851
13852 if Is_List_Member (N) then
13853 Insert_After (N, Vnode);
13854 end if;
13855 end Validate_Unchecked_Conversion;
13856
13857 ------------------------------------
13858 -- Validate_Unchecked_Conversions --
13859 ------------------------------------
13860
13861 procedure Validate_Unchecked_Conversions is
13862 begin
13863 for N in Unchecked_Conversions.First .. Unchecked_Conversions.Last loop
13864 declare
13865 T : UC_Entry renames Unchecked_Conversions.Table (N);
13866
13867 Act_Unit : constant Entity_Id := T.Act_Unit;
13868 Eloc : constant Source_Ptr := T.Eloc;
13869 Source : constant Entity_Id := T.Source;
13870 Target : constant Entity_Id := T.Target;
13871
13872 Source_Siz : Uint;
13873 Target_Siz : Uint;
13874
13875 begin
13876 -- Skip if function marked as warnings off
13877
13878 if Warnings_Off (Act_Unit) then
13879 goto Continue;
13880 end if;
13881
13882 -- This validation check, which warns if we have unequal sizes for
13883 -- unchecked conversion, and thus potentially implementation
13884 -- dependent semantics, is one of the few occasions on which we
13885 -- use the official RM size instead of Esize. See description in
13886 -- Einfo "Handling of Type'Size Values" for details.
13887
13888 if Serious_Errors_Detected = 0
13889 and then Known_Static_RM_Size (Source)
13890 and then Known_Static_RM_Size (Target)
13891
13892 -- Don't do the check if warnings off for either type, note the
13893 -- deliberate use of OR here instead of OR ELSE to get the flag
13894 -- Warnings_Off_Used set for both types if appropriate.
13895
13896 and then not (Has_Warnings_Off (Source)
13897 or
13898 Has_Warnings_Off (Target))
13899 then
13900 Source_Siz := RM_Size (Source);
13901 Target_Siz := RM_Size (Target);
13902
13903 if Source_Siz /= Target_Siz then
13904 Error_Msg
13905 ("?z?types for unchecked conversion have different sizes!",
13906 Eloc);
13907
13908 if All_Errors_Mode then
13909 Error_Msg_Name_1 := Chars (Source);
13910 Error_Msg_Uint_1 := Source_Siz;
13911 Error_Msg_Name_2 := Chars (Target);
13912 Error_Msg_Uint_2 := Target_Siz;
13913 Error_Msg ("\size of % is ^, size of % is ^?z?", Eloc);
13914
13915 Error_Msg_Uint_1 := UI_Abs (Source_Siz - Target_Siz);
13916
13917 if Is_Discrete_Type (Source)
13918 and then
13919 Is_Discrete_Type (Target)
13920 then
13921 if Source_Siz > Target_Siz then
13922 Error_Msg
13923 ("\?z?^ high order bits of source will "
13924 & "be ignored!", Eloc);
13925
13926 elsif Is_Unsigned_Type (Source) then
13927 Error_Msg
13928 ("\?z?source will be extended with ^ high order "
13929 & "zero bits!", Eloc);
13930
13931 else
13932 Error_Msg
13933 ("\?z?source will be extended with ^ high order "
13934 & "sign bits!", Eloc);
13935 end if;
13936
13937 elsif Source_Siz < Target_Siz then
13938 if Is_Discrete_Type (Target) then
13939 if Bytes_Big_Endian then
13940 Error_Msg
13941 ("\?z?target value will include ^ undefined "
13942 & "low order bits!", Eloc);
13943 else
13944 Error_Msg
13945 ("\?z?target value will include ^ undefined "
13946 & "high order bits!", Eloc);
13947 end if;
13948
13949 else
13950 Error_Msg
13951 ("\?z?^ trailing bits of target value will be "
13952 & "undefined!", Eloc);
13953 end if;
13954
13955 else pragma Assert (Source_Siz > Target_Siz);
13956 if Is_Discrete_Type (Source) then
13957 if Bytes_Big_Endian then
13958 Error_Msg
13959 ("\?z?^ low order bits of source will be "
13960 & "ignored!", Eloc);
13961 else
13962 Error_Msg
13963 ("\?z?^ high order bits of source will be "
13964 & "ignored!", Eloc);
13965 end if;
13966
13967 else
13968 Error_Msg
13969 ("\?z?^ trailing bits of source will be "
13970 & "ignored!", Eloc);
13971 end if;
13972 end if;
13973 end if;
13974 end if;
13975 end if;
13976
13977 -- If both types are access types, we need to check the alignment.
13978 -- If the alignment of both is specified, we can do it here.
13979
13980 if Serious_Errors_Detected = 0
13981 and then Is_Access_Type (Source)
13982 and then Is_Access_Type (Target)
13983 and then Target_Strict_Alignment
13984 and then Present (Designated_Type (Source))
13985 and then Present (Designated_Type (Target))
13986 then
13987 declare
13988 D_Source : constant Entity_Id := Designated_Type (Source);
13989 D_Target : constant Entity_Id := Designated_Type (Target);
13990
13991 begin
13992 if Known_Alignment (D_Source)
13993 and then
13994 Known_Alignment (D_Target)
13995 then
13996 declare
13997 Source_Align : constant Uint := Alignment (D_Source);
13998 Target_Align : constant Uint := Alignment (D_Target);
13999
14000 begin
14001 if Source_Align < Target_Align
14002 and then not Is_Tagged_Type (D_Source)
14003
14004 -- Suppress warning if warnings suppressed on either
14005 -- type or either designated type. Note the use of
14006 -- OR here instead of OR ELSE. That is intentional,
14007 -- we would like to set flag Warnings_Off_Used in
14008 -- all types for which warnings are suppressed.
14009
14010 and then not (Has_Warnings_Off (D_Source)
14011 or
14012 Has_Warnings_Off (D_Target)
14013 or
14014 Has_Warnings_Off (Source)
14015 or
14016 Has_Warnings_Off (Target))
14017 then
14018 Error_Msg_Uint_1 := Target_Align;
14019 Error_Msg_Uint_2 := Source_Align;
14020 Error_Msg_Node_1 := D_Target;
14021 Error_Msg_Node_2 := D_Source;
14022 Error_Msg
14023 ("?z?alignment of & (^) is stricter than "
14024 & "alignment of & (^)!", Eloc);
14025 Error_Msg
14026 ("\?z?resulting access value may have invalid "
14027 & "alignment!", Eloc);
14028 end if;
14029 end;
14030 end if;
14031 end;
14032 end if;
14033 end;
14034
14035 <<Continue>>
14036 null;
14037 end loop;
14038 end Validate_Unchecked_Conversions;
14039
14040 end Sem_Ch13;