1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2020, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. 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. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Errout; use Errout;
32 with Expander; use Expander;
33 with Exp_Ch6; use Exp_Ch6;
34 with Exp_Tss; use Exp_Tss;
35 with Exp_Util; use Exp_Util;
36 with Freeze; use Freeze;
37 with Itypes; use Itypes;
39 with Lib.Xref; use Lib.Xref;
40 with Namet; use Namet;
41 with Namet.Sp; use Namet.Sp;
42 with Nmake; use Nmake;
43 with Nlists; use Nlists;
45 with Restrict; use Restrict;
46 with Rident; use Rident;
48 with Sem_Aux; use Sem_Aux;
49 with Sem_Cat; use Sem_Cat;
50 with Sem_Ch3; use Sem_Ch3;
51 with Sem_Ch8; use Sem_Ch8;
52 with Sem_Ch13; use Sem_Ch13;
53 with Sem_Dim; use Sem_Dim;
54 with Sem_Eval; use Sem_Eval;
55 with Sem_Res; use Sem_Res;
56 with Sem_Util; use Sem_Util;
57 with Sem_Type; use Sem_Type;
58 with Sem_Warn; use Sem_Warn;
59 with Sinfo; use Sinfo;
60 with Snames; use Snames;
61 with Stringt; use Stringt;
62 with Stand; use Stand;
63 with Style; use Style;
64 with Targparm; use Targparm;
65 with Tbuild; use Tbuild;
66 with Uintp; use Uintp;
68 package body Sem_Aggr is
70 type Case_Bounds is record
72 -- Low bound of choice. Once we sort the Case_Table, then entries
73 -- will be in order of ascending Choice_Lo values.
76 -- High Bound of choice. The sort does not pay any attention to the
77 -- high bound, so choices 1 .. 4 and 1 .. 5 could be in either order.
80 -- If there are duplicates or missing entries, then in the sorted
81 -- table, this records the highest value among Choice_Hi values
82 -- seen so far, including this entry.
85 -- The node of the choice
88 type Case_Table_Type is array (Pos range <>) of Case_Bounds;
89 -- Table type used by Check_Case_Choices procedure
91 -----------------------
92 -- Local Subprograms --
93 -----------------------
95 procedure Sort_Case_Table (Case_Table : in out Case_Table_Type);
96 -- Sort the Case Table using the Lower Bound of each Choice as the key. A
97 -- simple insertion sort is used since the choices in a case statement will
98 -- usually be in near sorted order.
100 procedure Check_Can_Never_Be_Null (Typ : Entity_Id; Expr : Node_Id);
101 -- Ada 2005 (AI-231): Check bad usage of null for a component for which
102 -- null exclusion (NOT NULL) is specified. Typ can be an E_Array_Type for
103 -- the array case (the component type of the array will be used) or an
104 -- E_Component/E_Discriminant entity in the record case, in which case the
105 -- type of the component will be used for the test. If Typ is any other
106 -- kind of entity, the call is ignored. Expr is the component node in the
107 -- aggregate which is known to have a null value. A warning message will be
108 -- issued if the component is null excluding.
110 -- It would be better to pass the proper type for Typ ???
112 procedure Check_Expr_OK_In_Limited_Aggregate (Expr : Node_Id);
113 -- Check that Expr is either not limited or else is one of the cases of
114 -- expressions allowed for a limited component association (namely, an
115 -- aggregate, function call, or <> notation). Report error for violations.
116 -- Expression is also OK in an instance or inlining context, because we
117 -- have already preanalyzed and it is known to be type correct.
119 ------------------------------------------------------
120 -- Subprograms used for RECORD AGGREGATE Processing --
121 ------------------------------------------------------
123 procedure Resolve_Record_Aggregate (N : Node_Id; Typ : Entity_Id);
124 -- This procedure performs all the semantic checks required for record
125 -- aggregates. Note that for aggregates analysis and resolution go
126 -- hand in hand. Aggregate analysis has been delayed up to here and
127 -- it is done while resolving the aggregate.
129 -- N is the N_Aggregate node.
130 -- Typ is the record type for the aggregate resolution
132 -- While performing the semantic checks, this procedure builds a new
133 -- Component_Association_List where each record field appears alone in a
134 -- Component_Choice_List along with its corresponding expression. The
135 -- record fields in the Component_Association_List appear in the same order
136 -- in which they appear in the record type Typ.
138 -- Once this new Component_Association_List is built and all the semantic
139 -- checks performed, the original aggregate subtree is replaced with the
140 -- new named record aggregate just built. This new record aggregate has no
141 -- positional associations, so its Expressions field is set to No_List.
142 -- Note that subtree substitution is performed with Rewrite so as to be
143 -- able to retrieve the original aggregate.
145 -- The aggregate subtree manipulation performed by Resolve_Record_Aggregate
146 -- yields the aggregate format expected by Gigi. Typically, this kind of
147 -- tree manipulations are done in the expander. However, because the
148 -- semantic checks that need to be performed on record aggregates really go
149 -- hand in hand with the record aggregate normalization, the aggregate
150 -- subtree transformation is performed during resolution rather than
151 -- expansion. Had we decided otherwise we would have had to duplicate most
152 -- of the code in the expansion procedure Expand_Record_Aggregate. Note,
153 -- however, that all the expansion concerning aggregates for tagged records
154 -- is done in Expand_Record_Aggregate.
156 -- The algorithm of Resolve_Record_Aggregate proceeds as follows:
158 -- 1. Make sure that the record type against which the record aggregate
159 -- has to be resolved is not abstract. Furthermore if the type is a
160 -- null aggregate make sure the input aggregate N is also null.
162 -- 2. Verify that the structure of the aggregate is that of a record
163 -- aggregate. Specifically, look for component associations and ensure
164 -- that each choice list only has identifiers or the N_Others_Choice
165 -- node. Also make sure that if present, the N_Others_Choice occurs
166 -- last and by itself.
168 -- 3. If Typ contains discriminants, the values for each discriminant is
169 -- looked for. If the record type Typ has variants, we check that the
170 -- expressions corresponding to each discriminant ruling the (possibly
171 -- nested) variant parts of Typ, are static. This allows us to determine
172 -- the variant parts to which the rest of the aggregate must conform.
173 -- The names of discriminants with their values are saved in a new
174 -- association list, New_Assoc_List which is later augmented with the
175 -- names and values of the remaining components in the record type.
177 -- During this phase we also make sure that every discriminant is
178 -- assigned exactly one value. Note that when several values for a given
179 -- discriminant are found, semantic processing continues looking for
180 -- further errors. In this case it's the first discriminant value found
181 -- which we will be recorded.
183 -- IMPORTANT NOTE: For derived tagged types this procedure expects
184 -- First_Discriminant and Next_Discriminant to give the correct list
185 -- of discriminants, in the correct order.
187 -- 4. After all the discriminant values have been gathered, we can set the
188 -- Etype of the record aggregate. If Typ contains no discriminants this
189 -- is straightforward: the Etype of N is just Typ, otherwise a new
190 -- implicit constrained subtype of Typ is built to be the Etype of N.
192 -- 5. Gather the remaining record components according to the discriminant
193 -- values. This involves recursively traversing the record type
194 -- structure to see what variants are selected by the given discriminant
195 -- values. This processing is a little more convoluted if Typ is a
196 -- derived tagged types since we need to retrieve the record structure
197 -- of all the ancestors of Typ.
199 -- 6. After gathering the record components we look for their values in the
200 -- record aggregate and emit appropriate error messages should we not
201 -- find such values or should they be duplicated.
203 -- 7. We then make sure no illegal component names appear in the record
204 -- aggregate and make sure that the type of the record components
205 -- appearing in a same choice list is the same. Finally we ensure that
206 -- the others choice, if present, is used to provide the value of at
207 -- least a record component.
209 -- 8. The original aggregate node is replaced with the new named aggregate
210 -- built in steps 3 through 6, as explained earlier.
212 -- Given the complexity of record aggregate resolution, the primary goal of
213 -- this routine is clarity and simplicity rather than execution and storage
214 -- efficiency. If there are only positional components in the aggregate the
215 -- running time is linear. If there are associations the running time is
216 -- still linear as long as the order of the associations is not too far off
217 -- the order of the components in the record type. If this is not the case
218 -- the running time is at worst quadratic in the size of the association
221 procedure Check_Misspelled_Component
222 (Elements : Elist_Id;
223 Component : Node_Id);
224 -- Give possible misspelling diagnostic if Component is likely to be a
225 -- misspelling of one of the components of the Assoc_List. This is called
226 -- by Resolve_Aggr_Expr after producing an invalid component error message.
228 -----------------------------------------------------
229 -- Subprograms used for ARRAY AGGREGATE Processing --
230 -----------------------------------------------------
232 function Resolve_Array_Aggregate
235 Index_Constr : Node_Id;
236 Component_Typ : Entity_Id;
237 Others_Allowed : Boolean) return Boolean;
238 -- This procedure performs the semantic checks for an array aggregate.
239 -- True is returned if the aggregate resolution succeeds.
241 -- The procedure works by recursively checking each nested aggregate.
242 -- Specifically, after checking a sub-aggregate nested at the i-th level
243 -- we recursively check all the subaggregates at the i+1-st level (if any).
244 -- Note that for aggregates analysis and resolution go hand in hand.
245 -- Aggregate analysis has been delayed up to here and it is done while
246 -- resolving the aggregate.
248 -- N is the current N_Aggregate node to be checked.
250 -- Index is the index node corresponding to the array sub-aggregate that
251 -- we are currently checking (RM 4.3.3 (8)). Its Etype is the
252 -- corresponding index type (or subtype).
254 -- Index_Constr is the node giving the applicable index constraint if
255 -- any (RM 4.3.3 (10)). It "is a constraint provided by certain
256 -- contexts [...] that can be used to determine the bounds of the array
257 -- value specified by the aggregate". If Others_Allowed below is False
258 -- there is no applicable index constraint and this node is set to Index.
260 -- Component_Typ is the array component type.
262 -- Others_Allowed indicates whether an others choice is allowed
263 -- in the context where the top-level aggregate appeared.
265 -- The algorithm of Resolve_Array_Aggregate proceeds as follows:
267 -- 1. Make sure that the others choice, if present, is by itself and
268 -- appears last in the sub-aggregate. Check that we do not have
269 -- positional and named components in the array sub-aggregate (unless
270 -- the named association is an others choice). Finally if an others
271 -- choice is present, make sure it is allowed in the aggregate context.
273 -- 2. If the array sub-aggregate contains discrete_choices:
275 -- (A) Verify their validity. Specifically verify that:
277 -- (a) If a null range is present it must be the only possible
278 -- choice in the array aggregate.
280 -- (b) Ditto for a non static range.
282 -- (c) Ditto for a non static expression.
284 -- In addition this step analyzes and resolves each discrete_choice,
285 -- making sure that its type is the type of the corresponding Index.
286 -- If we are not at the lowest array aggregate level (in the case of
287 -- multi-dimensional aggregates) then invoke Resolve_Array_Aggregate
288 -- recursively on each component expression. Otherwise, resolve the
289 -- bottom level component expressions against the expected component
290 -- type ONLY IF the component corresponds to a single discrete choice
291 -- which is not an others choice (to see why read the DELAYED
292 -- COMPONENT RESOLUTION below).
294 -- (B) Determine the bounds of the sub-aggregate and lowest and
295 -- highest choice values.
297 -- 3. For positional aggregates:
299 -- (A) Loop over the component expressions either recursively invoking
300 -- Resolve_Array_Aggregate on each of these for multi-dimensional
301 -- array aggregates or resolving the bottom level component
302 -- expressions against the expected component type.
304 -- (B) Determine the bounds of the positional sub-aggregates.
306 -- 4. Try to determine statically whether the evaluation of the array
307 -- sub-aggregate raises Constraint_Error. If yes emit proper
308 -- warnings. The precise checks are the following:
310 -- (A) Check that the index range defined by aggregate bounds is
311 -- compatible with corresponding index subtype.
312 -- We also check against the base type. In fact it could be that
313 -- Low/High bounds of the base type are static whereas those of
314 -- the index subtype are not. Thus if we can statically catch
315 -- a problem with respect to the base type we are guaranteed
316 -- that the same problem will arise with the index subtype
318 -- (B) If we are dealing with a named aggregate containing an others
319 -- choice and at least one discrete choice then make sure the range
320 -- specified by the discrete choices does not overflow the
321 -- aggregate bounds. We also check against the index type and base
322 -- type bounds for the same reasons given in (A).
324 -- (C) If we are dealing with a positional aggregate with an others
325 -- choice make sure the number of positional elements specified
326 -- does not overflow the aggregate bounds. We also check against
327 -- the index type and base type bounds as mentioned in (A).
329 -- Finally construct an N_Range node giving the sub-aggregate bounds.
330 -- Set the Aggregate_Bounds field of the sub-aggregate to be this
331 -- N_Range. The routine Array_Aggr_Subtype below uses such N_Ranges
332 -- to build the appropriate aggregate subtype. Aggregate_Bounds
333 -- information is needed during expansion.
335 -- DELAYED COMPONENT RESOLUTION: The resolution of bottom level component
336 -- expressions in an array aggregate may call Duplicate_Subexpr or some
337 -- other routine that inserts code just outside the outermost aggregate.
338 -- If the array aggregate contains discrete choices or an others choice,
339 -- this may be wrong. Consider for instance the following example.
341 -- type Rec is record
345 -- type Acc_Rec is access Rec;
346 -- Arr : array (1..3) of Acc_Rec := (1 .. 3 => new Rec);
348 -- Then the transformation of "new Rec" that occurs during resolution
349 -- entails the following code modifications
351 -- P7b : constant Acc_Rec := new Rec;
353 -- Arr : array (1..3) of Acc_Rec := (1 .. 3 => P7b);
355 -- This code transformation is clearly wrong, since we need to call
356 -- "new Rec" for each of the 3 array elements. To avoid this problem we
357 -- delay resolution of the components of non positional array aggregates
358 -- to the expansion phase. As an optimization, if the discrete choice
359 -- specifies a single value we do not delay resolution.
361 function Array_Aggr_Subtype (N : Node_Id; Typ : Node_Id) return Entity_Id;
362 -- This routine returns the type or subtype of an array aggregate.
364 -- N is the array aggregate node whose type we return.
366 -- Typ is the context type in which N occurs.
368 -- This routine creates an implicit array subtype whose bounds are
369 -- those defined by the aggregate. When this routine is invoked
370 -- Resolve_Array_Aggregate has already processed aggregate N. Thus the
371 -- Aggregate_Bounds of each sub-aggregate, is an N_Range node giving the
372 -- sub-aggregate bounds. When building the aggregate itype, this function
373 -- traverses the array aggregate N collecting such Aggregate_Bounds and
374 -- constructs the proper array aggregate itype.
376 -- Note that in the case of multidimensional aggregates each inner
377 -- sub-aggregate corresponding to a given array dimension, may provide a
378 -- different bounds. If it is possible to determine statically that
379 -- some sub-aggregates corresponding to the same index do not have the
380 -- same bounds, then a warning is emitted. If such check is not possible
381 -- statically (because some sub-aggregate bounds are dynamic expressions)
382 -- then this job is left to the expander. In all cases the particular
383 -- bounds that this function will chose for a given dimension is the first
384 -- N_Range node for a sub-aggregate corresponding to that dimension.
386 -- Note that the Raises_Constraint_Error flag of an array aggregate
387 -- whose evaluation is determined to raise CE by Resolve_Array_Aggregate,
388 -- is set in Resolve_Array_Aggregate but the aggregate is not
389 -- immediately replaced with a raise CE. In fact, Array_Aggr_Subtype must
390 -- first construct the proper itype for the aggregate (Gigi needs
391 -- this). After constructing the proper itype we will eventually replace
392 -- the top-level aggregate with a raise CE (done in Resolve_Aggregate).
393 -- Of course in cases such as:
395 -- type Arr is array (integer range <>) of Integer;
396 -- A : Arr := (positive range -1 .. 2 => 0);
398 -- The bounds of the aggregate itype are cooked up to look reasonable
399 -- (in this particular case the bounds will be 1 .. 2).
401 procedure Make_String_Into_Aggregate (N : Node_Id);
402 -- A string literal can appear in a context in which a one dimensional
403 -- array of characters is expected. This procedure simply rewrites the
404 -- string as an aggregate, prior to resolution.
406 ---------------------------------
407 -- Delta aggregate processing --
408 ---------------------------------
410 procedure Resolve_Delta_Array_Aggregate (N : Node_Id; Typ : Entity_Id);
411 procedure Resolve_Delta_Record_Aggregate (N : Node_Id; Typ : Entity_Id);
413 ------------------------
414 -- Array_Aggr_Subtype --
415 ------------------------
417 function Array_Aggr_Subtype
419 Typ : Entity_Id) return Entity_Id
421 Aggr_Dimension : constant Pos := Number_Dimensions (Typ);
422 -- Number of aggregate index dimensions
424 Aggr_Range : array (1 .. Aggr_Dimension) of Node_Id := (others => Empty);
425 -- Constrained N_Range of each index dimension in our aggregate itype
427 Aggr_Low : array (1 .. Aggr_Dimension) of Node_Id := (others => Empty);
428 Aggr_High : array (1 .. Aggr_Dimension) of Node_Id := (others => Empty);
429 -- Low and High bounds for each index dimension in our aggregate itype
431 Is_Fully_Positional : Boolean := True;
433 procedure Collect_Aggr_Bounds (N : Node_Id; Dim : Pos);
434 -- N is an array (sub-)aggregate. Dim is the dimension corresponding
435 -- to (sub-)aggregate N. This procedure collects and removes the side
436 -- effects of the constrained N_Range nodes corresponding to each index
437 -- dimension of our aggregate itype. These N_Range nodes are collected
438 -- in Aggr_Range above.
440 -- Likewise collect in Aggr_Low & Aggr_High above the low and high
441 -- bounds of each index dimension. If, when collecting, two bounds
442 -- corresponding to the same dimension are static and found to differ,
443 -- then emit a warning, and mark N as raising Constraint_Error.
445 -------------------------
446 -- Collect_Aggr_Bounds --
447 -------------------------
449 procedure Collect_Aggr_Bounds (N : Node_Id; Dim : Pos) is
450 This_Range : constant Node_Id := Aggregate_Bounds (N);
451 -- The aggregate range node of this specific sub-aggregate
453 This_Low : constant Node_Id := Low_Bound (Aggregate_Bounds (N));
454 This_High : constant Node_Id := High_Bound (Aggregate_Bounds (N));
455 -- The aggregate bounds of this specific sub-aggregate
461 Remove_Side_Effects (This_Low, Variable_Ref => True);
462 Remove_Side_Effects (This_High, Variable_Ref => True);
464 -- Collect the first N_Range for a given dimension that you find.
465 -- For a given dimension they must be all equal anyway.
467 if No (Aggr_Range (Dim)) then
468 Aggr_Low (Dim) := This_Low;
469 Aggr_High (Dim) := This_High;
470 Aggr_Range (Dim) := This_Range;
473 if Compile_Time_Known_Value (This_Low) then
474 if not Compile_Time_Known_Value (Aggr_Low (Dim)) then
475 Aggr_Low (Dim) := This_Low;
477 elsif Expr_Value (This_Low) /= Expr_Value (Aggr_Low (Dim)) then
478 Set_Raises_Constraint_Error (N);
479 Error_Msg_Warn := SPARK_Mode /= On;
480 Error_Msg_N ("sub-aggregate low bound mismatch<<", N);
481 Error_Msg_N ("\Constraint_Error [<<", N);
485 if Compile_Time_Known_Value (This_High) then
486 if not Compile_Time_Known_Value (Aggr_High (Dim)) then
487 Aggr_High (Dim) := This_High;
490 Expr_Value (This_High) /= Expr_Value (Aggr_High (Dim))
492 Set_Raises_Constraint_Error (N);
493 Error_Msg_Warn := SPARK_Mode /= On;
494 Error_Msg_N ("sub-aggregate high bound mismatch<<", N);
495 Error_Msg_N ("\Constraint_Error [<<", N);
500 if Dim < Aggr_Dimension then
502 -- Process positional components
504 if Present (Expressions (N)) then
505 Expr := First (Expressions (N));
506 while Present (Expr) loop
507 Collect_Aggr_Bounds (Expr, Dim + 1);
512 -- Process component associations
514 if Present (Component_Associations (N)) then
515 Is_Fully_Positional := False;
517 Assoc := First (Component_Associations (N));
518 while Present (Assoc) loop
519 Expr := Expression (Assoc);
520 Collect_Aggr_Bounds (Expr, Dim + 1);
525 end Collect_Aggr_Bounds;
527 -- Array_Aggr_Subtype variables
530 -- The final itype of the overall aggregate
532 Index_Constraints : constant List_Id := New_List;
533 -- The list of index constraints of the aggregate itype
535 -- Start of processing for Array_Aggr_Subtype
538 -- Make sure that the list of index constraints is properly attached to
539 -- the tree, and then collect the aggregate bounds.
541 Set_Parent (Index_Constraints, N);
542 Collect_Aggr_Bounds (N, 1);
544 -- Build the list of constrained indexes of our aggregate itype
546 for J in 1 .. Aggr_Dimension loop
547 Create_Index : declare
548 Index_Base : constant Entity_Id :=
549 Base_Type (Etype (Aggr_Range (J)));
550 Index_Typ : Entity_Id;
553 -- Construct the Index subtype, and associate it with the range
554 -- construct that generates it.
557 Create_Itype (Subtype_Kind (Ekind (Index_Base)), Aggr_Range (J));
559 Set_Etype (Index_Typ, Index_Base);
561 if Is_Character_Type (Index_Base) then
562 Set_Is_Character_Type (Index_Typ);
565 Set_Size_Info (Index_Typ, (Index_Base));
566 Set_RM_Size (Index_Typ, RM_Size (Index_Base));
567 Set_First_Rep_Item (Index_Typ, First_Rep_Item (Index_Base));
568 Set_Scalar_Range (Index_Typ, Aggr_Range (J));
570 if Is_Discrete_Or_Fixed_Point_Type (Index_Typ) then
571 Set_RM_Size (Index_Typ, UI_From_Int (Minimum_Size (Index_Typ)));
574 Set_Etype (Aggr_Range (J), Index_Typ);
576 Append (Aggr_Range (J), To => Index_Constraints);
580 -- Now build the Itype
582 Itype := Create_Itype (E_Array_Subtype, N);
584 Set_First_Rep_Item (Itype, First_Rep_Item (Typ));
585 Set_Convention (Itype, Convention (Typ));
586 Set_Depends_On_Private (Itype, Has_Private_Component (Typ));
587 Set_Etype (Itype, Base_Type (Typ));
588 Set_Has_Alignment_Clause (Itype, Has_Alignment_Clause (Typ));
589 Set_Is_Aliased (Itype, Is_Aliased (Typ));
590 Set_Is_Independent (Itype, Is_Independent (Typ));
591 Set_Depends_On_Private (Itype, Depends_On_Private (Typ));
593 Copy_Suppress_Status (Index_Check, Typ, Itype);
594 Copy_Suppress_Status (Length_Check, Typ, Itype);
596 Set_First_Index (Itype, First (Index_Constraints));
597 Set_Is_Constrained (Itype, True);
598 Set_Is_Internal (Itype, True);
600 if Has_Predicates (Typ) then
601 Set_Has_Predicates (Itype);
603 -- If the base type has a predicate, capture the predicated parent
604 -- or the existing predicate function for SPARK use.
606 if Present (Predicate_Function (Typ)) then
607 Set_Predicate_Function (Itype, Predicate_Function (Typ));
609 elsif Is_Itype (Typ) then
610 Set_Predicated_Parent (Itype, Predicated_Parent (Typ));
613 Set_Predicated_Parent (Itype, Typ);
617 -- A simple optimization: purely positional aggregates of static
618 -- components should be passed to gigi unexpanded whenever possible, and
619 -- regardless of the staticness of the bounds themselves. Subsequent
620 -- checks in exp_aggr verify that type is not packed, etc.
622 Set_Size_Known_At_Compile_Time
625 and then Comes_From_Source (N)
626 and then Size_Known_At_Compile_Time (Component_Type (Typ)));
628 -- We always need a freeze node for a packed array subtype, so that we
629 -- can build the Packed_Array_Impl_Type corresponding to the subtype. If
630 -- expansion is disabled, the packed array subtype is not built, and we
631 -- must not generate a freeze node for the type, or else it will appear
632 -- incomplete to gigi.
635 and then not In_Spec_Expression
636 and then Expander_Active
638 Freeze_Itype (Itype, N);
642 end Array_Aggr_Subtype;
644 --------------------------------
645 -- Check_Misspelled_Component --
646 --------------------------------
648 procedure Check_Misspelled_Component
649 (Elements : Elist_Id;
652 Max_Suggestions : constant := 2;
654 Nr_Of_Suggestions : Natural := 0;
655 Suggestion_1 : Entity_Id := Empty;
656 Suggestion_2 : Entity_Id := Empty;
657 Component_Elmt : Elmt_Id;
660 -- All the components of List are matched against Component and a count
661 -- is maintained of possible misspellings. When at the end of the
662 -- analysis there are one or two (not more) possible misspellings,
663 -- these misspellings will be suggested as possible corrections.
665 Component_Elmt := First_Elmt (Elements);
666 while Nr_Of_Suggestions <= Max_Suggestions
667 and then Present (Component_Elmt)
669 if Is_Bad_Spelling_Of
670 (Chars (Node (Component_Elmt)),
673 Nr_Of_Suggestions := Nr_Of_Suggestions + 1;
675 case Nr_Of_Suggestions is
676 when 1 => Suggestion_1 := Node (Component_Elmt);
677 when 2 => Suggestion_2 := Node (Component_Elmt);
682 Next_Elmt (Component_Elmt);
685 -- Report at most two suggestions
687 if Nr_Of_Suggestions = 1 then
688 Error_Msg_NE -- CODEFIX
689 ("\possible misspelling of&", Component, Suggestion_1);
691 elsif Nr_Of_Suggestions = 2 then
692 Error_Msg_Node_2 := Suggestion_2;
693 Error_Msg_NE -- CODEFIX
694 ("\possible misspelling of& or&", Component, Suggestion_1);
696 end Check_Misspelled_Component;
698 ----------------------------------------
699 -- Check_Expr_OK_In_Limited_Aggregate --
700 ----------------------------------------
702 procedure Check_Expr_OK_In_Limited_Aggregate (Expr : Node_Id) is
704 if Is_Limited_Type (Etype (Expr))
705 and then Comes_From_Source (Expr)
707 if In_Instance_Body or else In_Inlined_Body then
710 elsif not OK_For_Limited_Init (Etype (Expr), Expr) then
712 ("initialization not allowed for limited types", Expr);
713 Explain_Limited_Type (Etype (Expr), Expr);
716 end Check_Expr_OK_In_Limited_Aggregate;
718 -------------------------
719 -- Is_Others_Aggregate --
720 -------------------------
722 function Is_Others_Aggregate (Aggr : Node_Id) return Boolean is
723 Assoc : constant List_Id := Component_Associations (Aggr);
726 return No (Expressions (Aggr))
727 and then Nkind (First (Choice_List (First (Assoc)))) = N_Others_Choice;
728 end Is_Others_Aggregate;
730 -------------------------
731 -- Is_Single_Aggregate --
732 -------------------------
734 function Is_Single_Aggregate (Aggr : Node_Id) return Boolean is
735 Assoc : constant List_Id := Component_Associations (Aggr);
738 return No (Expressions (Aggr))
739 and then No (Next (First (Assoc)))
740 and then No (Next (First (Choice_List (First (Assoc)))));
741 end Is_Single_Aggregate;
743 --------------------------------
744 -- Make_String_Into_Aggregate --
745 --------------------------------
747 procedure Make_String_Into_Aggregate (N : Node_Id) is
748 Exprs : constant List_Id := New_List;
749 Loc : constant Source_Ptr := Sloc (N);
750 Str : constant String_Id := Strval (N);
751 Strlen : constant Nat := String_Length (Str);
759 for J in 1 .. Strlen loop
760 C := Get_String_Char (Str, J);
761 Set_Character_Literal_Name (C);
764 Make_Character_Literal (P,
766 Char_Literal_Value => UI_From_CC (C));
767 Set_Etype (C_Node, Any_Character);
768 Append_To (Exprs, C_Node);
771 -- Something special for wide strings???
774 New_N := Make_Aggregate (Loc, Expressions => Exprs);
775 Set_Analyzed (New_N);
776 Set_Etype (New_N, Any_Composite);
779 end Make_String_Into_Aggregate;
781 -----------------------
782 -- Resolve_Aggregate --
783 -----------------------
785 procedure Resolve_Aggregate (N : Node_Id; Typ : Entity_Id) is
786 Loc : constant Source_Ptr := Sloc (N);
788 Aggr_Subtyp : Entity_Id;
789 -- The actual aggregate subtype. This is not necessarily the same as Typ
790 -- which is the subtype of the context in which the aggregate was found.
793 -- Ignore junk empty aggregate resulting from parser error
795 if No (Expressions (N))
796 and then No (Component_Associations (N))
797 and then not Null_Record_Present (N)
802 -- If the aggregate has box-initialized components, its type must be
803 -- frozen so that initialization procedures can properly be called
804 -- in the resolution that follows. The replacement of boxes with
805 -- initialization calls is properly an expansion activity but it must
806 -- be done during resolution.
809 and then Present (Component_Associations (N))
815 Comp := First (Component_Associations (N));
816 while Present (Comp) loop
817 if Box_Present (Comp) then
818 Insert_Actions (N, Freeze_Entity (Typ, N));
827 -- Check for aggregates not allowed in configurable run-time mode.
828 -- We allow all cases of aggregates that do not come from source, since
829 -- these are all assumed to be small (e.g. bounds of a string literal).
830 -- We also allow aggregates of types we know to be small.
832 if not Support_Aggregates_On_Target
833 and then Comes_From_Source (N)
834 and then (not Known_Static_Esize (Typ) or else Esize (Typ) > 64)
836 Error_Msg_CRT ("aggregate", N);
839 -- Ada 2005 (AI-287): Limited aggregates allowed
841 -- In an instance, ignore aggregate subcomponents tnat may be limited,
842 -- because they originate in view conflicts. If the original aggregate
843 -- is legal and the actuals are legal, the aggregate itself is legal.
845 if Is_Limited_Type (Typ)
846 and then Ada_Version < Ada_2005
847 and then not In_Instance
849 Error_Msg_N ("aggregate type cannot be limited", N);
850 Explain_Limited_Type (Typ, N);
852 elsif Is_Class_Wide_Type (Typ) then
853 Error_Msg_N ("type of aggregate cannot be class-wide", N);
855 elsif Typ = Any_String
856 or else Typ = Any_Composite
858 Error_Msg_N ("no unique type for aggregate", N);
859 Set_Etype (N, Any_Composite);
861 elsif Is_Array_Type (Typ) and then Null_Record_Present (N) then
862 Error_Msg_N ("null record forbidden in array aggregate", N);
864 elsif Is_Record_Type (Typ) then
865 Resolve_Record_Aggregate (N, Typ);
867 elsif Is_Array_Type (Typ) then
869 -- First a special test, for the case of a positional aggregate of
870 -- characters which can be replaced by a string literal.
872 -- Do not perform this transformation if this was a string literal
873 -- to start with, whose components needed constraint checks, or if
874 -- the component type is non-static, because it will require those
875 -- checks and be transformed back into an aggregate. If the index
876 -- type is not Integer the aggregate may represent a user-defined
877 -- string type but the context might need the original type so we
878 -- do not perform the transformation at this point.
880 if Number_Dimensions (Typ) = 1
881 and then Is_Standard_Character_Type (Component_Type (Typ))
882 and then No (Component_Associations (N))
883 and then not Is_Limited_Composite (Typ)
884 and then not Is_Private_Composite (Typ)
885 and then not Is_Bit_Packed_Array (Typ)
886 and then Nkind (Original_Node (Parent (N))) /= N_String_Literal
887 and then Is_OK_Static_Subtype (Component_Type (Typ))
888 and then Base_Type (Etype (First_Index (Typ))) =
889 Base_Type (Standard_Integer)
895 Expr := First (Expressions (N));
896 while Present (Expr) loop
897 exit when Nkind (Expr) /= N_Character_Literal;
904 Expr := First (Expressions (N));
905 while Present (Expr) loop
906 Store_String_Char (UI_To_CC (Char_Literal_Value (Expr)));
910 Rewrite (N, Make_String_Literal (Loc, End_String));
912 Analyze_And_Resolve (N, Typ);
918 -- Here if we have a real aggregate to deal with
920 Array_Aggregate : declare
921 Aggr_Resolved : Boolean;
923 Aggr_Typ : constant Entity_Id := Etype (Typ);
924 -- This is the unconstrained array type, which is the type against
925 -- which the aggregate is to be resolved. Typ itself is the array
926 -- type of the context which may not be the same subtype as the
927 -- subtype for the final aggregate.
930 -- In the following we determine whether an OTHERS choice is
931 -- allowed inside the array aggregate. The test checks the context
932 -- in which the array aggregate occurs. If the context does not
933 -- permit it, or the aggregate type is unconstrained, an OTHERS
934 -- choice is not allowed (except that it is always allowed on the
935 -- right-hand side of an assignment statement; in this case the
936 -- constrainedness of the type doesn't matter, because an array
937 -- object is always constrained).
939 -- If expansion is disabled (generic context, or semantics-only
940 -- mode) actual subtypes cannot be constructed, and the type of an
941 -- object may be its unconstrained nominal type. However, if the
942 -- context is an assignment statement, OTHERS is allowed, because
943 -- the target of the assignment will have a constrained subtype
944 -- when fully compiled. Ditto if the context is an initialization
945 -- procedure where a component may have a predicate function that
946 -- carries the base type.
948 -- Note that there is no node for Explicit_Actual_Parameter.
949 -- To test for this context we therefore have to test for node
950 -- N_Parameter_Association which itself appears only if there is a
951 -- formal parameter. Consequently we also need to test for
952 -- N_Procedure_Call_Statement or N_Function_Call.
954 -- The context may be an N_Reference node, created by expansion.
955 -- Legality of the others clause was established in the source,
956 -- so the context is legal.
958 Set_Etype (N, Aggr_Typ); -- May be overridden later on
960 if Nkind (Parent (N)) = N_Assignment_Statement
961 or else Inside_Init_Proc
962 or else (Is_Constrained (Typ)
963 and then Nkind_In (Parent (N),
964 N_Parameter_Association,
966 N_Procedure_Call_Statement,
967 N_Generic_Association,
968 N_Formal_Object_Declaration,
969 N_Simple_Return_Statement,
970 N_Object_Declaration,
971 N_Component_Declaration,
972 N_Parameter_Specification,
973 N_Qualified_Expression,
976 N_Extension_Aggregate,
977 N_Component_Association,
978 N_Case_Expression_Alternative,
980 N_Expression_With_Actions))
983 Resolve_Array_Aggregate
985 Index => First_Index (Aggr_Typ),
986 Index_Constr => First_Index (Typ),
987 Component_Typ => Component_Type (Typ),
988 Others_Allowed => True);
991 Resolve_Array_Aggregate
993 Index => First_Index (Aggr_Typ),
994 Index_Constr => First_Index (Aggr_Typ),
995 Component_Typ => Component_Type (Typ),
996 Others_Allowed => False);
999 if not Aggr_Resolved then
1001 -- A parenthesized expression may have been intended as an
1002 -- aggregate, leading to a type error when analyzing the
1003 -- component. This can also happen for a nested component
1004 -- (see Analyze_Aggr_Expr).
1006 if Paren_Count (N) > 0 then
1008 ("positional aggregate cannot have one component", N);
1011 Aggr_Subtyp := Any_Composite;
1014 Aggr_Subtyp := Array_Aggr_Subtype (N, Typ);
1017 Set_Etype (N, Aggr_Subtyp);
1018 end Array_Aggregate;
1020 elsif Is_Private_Type (Typ)
1021 and then Present (Full_View (Typ))
1022 and then (In_Inlined_Body or In_Instance_Body)
1023 and then Is_Composite_Type (Full_View (Typ))
1025 Resolve (N, Full_View (Typ));
1028 Error_Msg_N ("illegal context for aggregate", N);
1031 -- If we can determine statically that the evaluation of the aggregate
1032 -- raises Constraint_Error, then replace the aggregate with an
1033 -- N_Raise_Constraint_Error node, but set the Etype to the right
1034 -- aggregate subtype. Gigi needs this.
1036 if Raises_Constraint_Error (N) then
1037 Aggr_Subtyp := Etype (N);
1039 Make_Raise_Constraint_Error (Loc, Reason => CE_Range_Check_Failed));
1040 Set_Raises_Constraint_Error (N);
1041 Set_Etype (N, Aggr_Subtyp);
1045 Check_Function_Writable_Actuals (N);
1046 end Resolve_Aggregate;
1048 -----------------------------
1049 -- Resolve_Array_Aggregate --
1050 -----------------------------
1052 function Resolve_Array_Aggregate
1055 Index_Constr : Node_Id;
1056 Component_Typ : Entity_Id;
1057 Others_Allowed : Boolean) return Boolean
1059 Loc : constant Source_Ptr := Sloc (N);
1061 Failure : constant Boolean := False;
1062 Success : constant Boolean := True;
1064 Index_Typ : constant Entity_Id := Etype (Index);
1065 Index_Typ_Low : constant Node_Id := Type_Low_Bound (Index_Typ);
1066 Index_Typ_High : constant Node_Id := Type_High_Bound (Index_Typ);
1067 -- The type of the index corresponding to the array sub-aggregate along
1068 -- with its low and upper bounds.
1070 Index_Base : constant Entity_Id := Base_Type (Index_Typ);
1071 Index_Base_Low : constant Node_Id := Type_Low_Bound (Index_Base);
1072 Index_Base_High : constant Node_Id := Type_High_Bound (Index_Base);
1073 -- Ditto for the base type
1075 Others_Present : Boolean := False;
1077 Nb_Choices : Nat := 0;
1078 -- Contains the overall number of named choices in this sub-aggregate
1080 function Add (Val : Uint; To : Node_Id) return Node_Id;
1081 -- Creates a new expression node where Val is added to expression To.
1082 -- Tries to constant fold whenever possible. To must be an already
1083 -- analyzed expression.
1085 procedure Check_Bound (BH : Node_Id; AH : in out Node_Id);
1086 -- Checks that AH (the upper bound of an array aggregate) is less than
1087 -- or equal to BH (the upper bound of the index base type). If the check
1088 -- fails, a warning is emitted, the Raises_Constraint_Error flag of N is
1089 -- set, and AH is replaced with a duplicate of BH.
1091 procedure Check_Bounds (L, H : Node_Id; AL, AH : Node_Id);
1092 -- Checks that range AL .. AH is compatible with range L .. H. Emits a
1093 -- warning if not and sets the Raises_Constraint_Error flag in N.
1095 procedure Check_Length (L, H : Node_Id; Len : Uint);
1096 -- Checks that range L .. H contains at least Len elements. Emits a
1097 -- warning if not and sets the Raises_Constraint_Error flag in N.
1099 function Dynamic_Or_Null_Range (L, H : Node_Id) return Boolean;
1100 -- Returns True if range L .. H is dynamic or null
1102 procedure Get (Value : out Uint; From : Node_Id; OK : out Boolean);
1103 -- Given expression node From, this routine sets OK to False if it
1104 -- cannot statically evaluate From. Otherwise it stores this static
1105 -- value into Value.
1107 function Resolve_Aggr_Expr
1109 Single_Elmt : Boolean) return Boolean;
1110 -- Resolves aggregate expression Expr. Returns False if resolution
1111 -- fails. If Single_Elmt is set to False, the expression Expr may be
1112 -- used to initialize several array aggregate elements (this can happen
1113 -- for discrete choices such as "L .. H => Expr" or the OTHERS choice).
1114 -- In this event we do not resolve Expr unless expansion is disabled.
1115 -- To know why, see the DELAYED COMPONENT RESOLUTION note above.
1117 -- NOTE: In the case of "... => <>", we pass the in the
1118 -- N_Component_Association node as Expr, since there is no Expression in
1119 -- that case, and we need a Sloc for the error message.
1121 procedure Resolve_Iterated_Component_Association
1123 Index_Typ : Entity_Id);
1130 function Add (Val : Uint; To : Node_Id) return Node_Id is
1136 if Raises_Constraint_Error (To) then
1140 -- First test if we can do constant folding
1142 if Compile_Time_Known_Value (To)
1143 or else Nkind (To) = N_Integer_Literal
1145 Expr_Pos := Make_Integer_Literal (Loc, Expr_Value (To) + Val);
1146 Set_Is_Static_Expression (Expr_Pos);
1147 Set_Etype (Expr_Pos, Etype (To));
1148 Set_Analyzed (Expr_Pos, Analyzed (To));
1150 if not Is_Enumeration_Type (Index_Typ) then
1153 -- If we are dealing with enumeration return
1154 -- Index_Typ'Val (Expr_Pos)
1158 Make_Attribute_Reference
1160 Prefix => New_Occurrence_Of (Index_Typ, Loc),
1161 Attribute_Name => Name_Val,
1162 Expressions => New_List (Expr_Pos));
1168 -- If we are here no constant folding possible
1170 if not Is_Enumeration_Type (Index_Base) then
1173 Left_Opnd => Duplicate_Subexpr (To),
1174 Right_Opnd => Make_Integer_Literal (Loc, Val));
1176 -- If we are dealing with enumeration return
1177 -- Index_Typ'Val (Index_Typ'Pos (To) + Val)
1181 Make_Attribute_Reference
1183 Prefix => New_Occurrence_Of (Index_Typ, Loc),
1184 Attribute_Name => Name_Pos,
1185 Expressions => New_List (Duplicate_Subexpr (To)));
1189 Left_Opnd => To_Pos,
1190 Right_Opnd => Make_Integer_Literal (Loc, Val));
1193 Make_Attribute_Reference
1195 Prefix => New_Occurrence_Of (Index_Typ, Loc),
1196 Attribute_Name => Name_Val,
1197 Expressions => New_List (Expr_Pos));
1199 -- If the index type has a non standard representation, the
1200 -- attributes 'Val and 'Pos expand into function calls and the
1201 -- resulting expression is considered non-safe for reevaluation
1202 -- by the backend. Relocate it into a constant temporary in order
1203 -- to make it safe for reevaluation.
1205 if Has_Non_Standard_Rep (Etype (N)) then
1210 Def_Id := Make_Temporary (Loc, 'R', Expr);
1211 Set_Etype (Def_Id, Index_Typ);
1213 Make_Object_Declaration (Loc,
1214 Defining_Identifier => Def_Id,
1215 Object_Definition =>
1216 New_Occurrence_Of (Index_Typ, Loc),
1217 Constant_Present => True,
1218 Expression => Relocate_Node (Expr)));
1220 Expr := New_Occurrence_Of (Def_Id, Loc);
1232 procedure Check_Bound (BH : Node_Id; AH : in out Node_Id) is
1240 Get (Value => Val_BH, From => BH, OK => OK_BH);
1241 Get (Value => Val_AH, From => AH, OK => OK_AH);
1243 if OK_BH and then OK_AH and then Val_BH < Val_AH then
1244 Set_Raises_Constraint_Error (N);
1245 Error_Msg_Warn := SPARK_Mode /= On;
1246 Error_Msg_N ("upper bound out of range<<", AH);
1247 Error_Msg_N ("\Constraint_Error [<<", AH);
1249 -- You need to set AH to BH or else in the case of enumerations
1250 -- indexes we will not be able to resolve the aggregate bounds.
1252 AH := Duplicate_Subexpr (BH);
1260 procedure Check_Bounds (L, H : Node_Id; AL, AH : Node_Id) is
1271 pragma Warnings (Off, OK_AL);
1272 pragma Warnings (Off, OK_AH);
1275 if Raises_Constraint_Error (N)
1276 or else Dynamic_Or_Null_Range (AL, AH)
1281 Get (Value => Val_L, From => L, OK => OK_L);
1282 Get (Value => Val_H, From => H, OK => OK_H);
1284 Get (Value => Val_AL, From => AL, OK => OK_AL);
1285 Get (Value => Val_AH, From => AH, OK => OK_AH);
1287 if OK_L and then Val_L > Val_AL then
1288 Set_Raises_Constraint_Error (N);
1289 Error_Msg_Warn := SPARK_Mode /= On;
1290 Error_Msg_N ("lower bound of aggregate out of range<<", N);
1291 Error_Msg_N ("\Constraint_Error [<<", N);
1294 if OK_H and then Val_H < Val_AH then
1295 Set_Raises_Constraint_Error (N);
1296 Error_Msg_Warn := SPARK_Mode /= On;
1297 Error_Msg_N ("upper bound of aggregate out of range<<", N);
1298 Error_Msg_N ("\Constraint_Error [<<", N);
1306 procedure Check_Length (L, H : Node_Id; Len : Uint) is
1316 if Raises_Constraint_Error (N) then
1320 Get (Value => Val_L, From => L, OK => OK_L);
1321 Get (Value => Val_H, From => H, OK => OK_H);
1323 if not OK_L or else not OK_H then
1327 -- If null range length is zero
1329 if Val_L > Val_H then
1330 Range_Len := Uint_0;
1332 Range_Len := Val_H - Val_L + 1;
1335 if Range_Len < Len then
1336 Set_Raises_Constraint_Error (N);
1337 Error_Msg_Warn := SPARK_Mode /= On;
1338 Error_Msg_N ("too many elements<<", N);
1339 Error_Msg_N ("\Constraint_Error [<<", N);
1343 ---------------------------
1344 -- Dynamic_Or_Null_Range --
1345 ---------------------------
1347 function Dynamic_Or_Null_Range (L, H : Node_Id) return Boolean is
1355 Get (Value => Val_L, From => L, OK => OK_L);
1356 Get (Value => Val_H, From => H, OK => OK_H);
1358 return not OK_L or else not OK_H
1359 or else not Is_OK_Static_Expression (L)
1360 or else not Is_OK_Static_Expression (H)
1361 or else Val_L > Val_H;
1362 end Dynamic_Or_Null_Range;
1368 procedure Get (Value : out Uint; From : Node_Id; OK : out Boolean) is
1372 if Compile_Time_Known_Value (From) then
1373 Value := Expr_Value (From);
1375 -- If expression From is something like Some_Type'Val (10) then
1378 elsif Nkind (From) = N_Attribute_Reference
1379 and then Attribute_Name (From) = Name_Val
1380 and then Compile_Time_Known_Value (First (Expressions (From)))
1382 Value := Expr_Value (First (Expressions (From)));
1389 -----------------------
1390 -- Resolve_Aggr_Expr --
1391 -----------------------
1393 function Resolve_Aggr_Expr
1395 Single_Elmt : Boolean) return Boolean
1397 Nxt_Ind : constant Node_Id := Next_Index (Index);
1398 Nxt_Ind_Constr : constant Node_Id := Next_Index (Index_Constr);
1399 -- Index is the current index corresponding to the expression
1401 Resolution_OK : Boolean := True;
1402 -- Set to False if resolution of the expression failed
1405 -- Defend against previous errors
1407 if Nkind (Expr) = N_Error
1408 or else Error_Posted (Expr)
1413 -- If the array type against which we are resolving the aggregate
1414 -- has several dimensions, the expressions nested inside the
1415 -- aggregate must be further aggregates (or strings).
1417 if Present (Nxt_Ind) then
1418 if Nkind (Expr) /= N_Aggregate then
1420 -- A string literal can appear where a one-dimensional array
1421 -- of characters is expected. If the literal looks like an
1422 -- operator, it is still an operator symbol, which will be
1423 -- transformed into a string when analyzed.
1425 if Is_Character_Type (Component_Typ)
1426 and then No (Next_Index (Nxt_Ind))
1427 and then Nkind_In (Expr, N_String_Literal, N_Operator_Symbol)
1429 -- A string literal used in a multidimensional array
1430 -- aggregate in place of the final one-dimensional
1431 -- aggregate must not be enclosed in parentheses.
1433 if Paren_Count (Expr) /= 0 then
1434 Error_Msg_N ("no parenthesis allowed here", Expr);
1437 Make_String_Into_Aggregate (Expr);
1440 Error_Msg_N ("nested array aggregate expected", Expr);
1442 -- If the expression is parenthesized, this may be
1443 -- a missing component association for a 1-aggregate.
1445 if Paren_Count (Expr) > 0 then
1447 ("\if single-component aggregate is intended, "
1448 & "write e.g. (1 ='> ...)", Expr);
1455 -- If it's "... => <>", nothing to resolve
1457 if Nkind (Expr) = N_Component_Association then
1458 pragma Assert (Box_Present (Expr));
1462 -- Ada 2005 (AI-231): Propagate the type to the nested aggregate.
1463 -- Required to check the null-exclusion attribute (if present).
1464 -- This value may be overridden later on.
1466 Set_Etype (Expr, Etype (N));
1468 Resolution_OK := Resolve_Array_Aggregate
1469 (Expr, Nxt_Ind, Nxt_Ind_Constr, Component_Typ, Others_Allowed);
1472 -- If it's "... => <>", nothing to resolve
1474 if Nkind (Expr) = N_Component_Association then
1475 pragma Assert (Box_Present (Expr));
1479 -- Do not resolve the expressions of discrete or others choices
1480 -- unless the expression covers a single component, or the
1481 -- expander is inactive.
1483 -- In SPARK mode, expressions that can perform side effects will
1484 -- be recognized by the gnat2why back-end, and the whole
1485 -- subprogram will be ignored. So semantic analysis can be
1486 -- performed safely.
1489 or else not Expander_Active
1490 or else In_Spec_Expression
1492 Analyze_And_Resolve (Expr, Component_Typ);
1493 Check_Expr_OK_In_Limited_Aggregate (Expr);
1494 Check_Non_Static_Context (Expr);
1495 Aggregate_Constraint_Checks (Expr, Component_Typ);
1496 Check_Unset_Reference (Expr);
1500 -- If an aggregate component has a type with predicates, an explicit
1501 -- predicate check must be applied, as for an assignment statement,
1502 -- because the aggregate might not be expanded into individual
1503 -- component assignments. If the expression covers several components
1504 -- the analysis and the predicate check take place later.
1506 if Has_Predicates (Component_Typ)
1507 and then Analyzed (Expr)
1509 Apply_Predicate_Check (Expr, Component_Typ);
1512 if Raises_Constraint_Error (Expr)
1513 and then Nkind (Parent (Expr)) /= N_Component_Association
1515 Set_Raises_Constraint_Error (N);
1518 -- If the expression has been marked as requiring a range check,
1519 -- then generate it here. It's a bit odd to be generating such
1520 -- checks in the analyzer, but harmless since Generate_Range_Check
1521 -- does nothing (other than making sure Do_Range_Check is set) if
1522 -- the expander is not active.
1524 if Do_Range_Check (Expr) then
1525 Generate_Range_Check (Expr, Component_Typ, CE_Range_Check_Failed);
1528 return Resolution_OK;
1529 end Resolve_Aggr_Expr;
1531 --------------------------------------------
1532 -- Resolve_Iterated_Component_Association --
1533 --------------------------------------------
1535 procedure Resolve_Iterated_Component_Association
1537 Index_Typ : Entity_Id)
1539 Loc : constant Source_Ptr := Sloc (N);
1548 -- An element iterator specification cannot appear in
1549 -- an array aggregate because it does not provide index
1550 -- values for the association. This must be a semantic
1551 -- check because the parser cannot tell whether this is
1552 -- an array aggregate or a container aggregate.
1554 if Present (Iterator_Specification (N)) then
1555 Error_Msg_N ("container element Iterator cannot appear "
1556 & "in an array aggregate", N);
1560 Choice := First (Discrete_Choices (N));
1562 while Present (Choice) loop
1563 if Nkind (Choice) = N_Others_Choice then
1564 Others_Present := True;
1569 -- Choice can be a subtype name, a range, or an expression
1571 if Is_Entity_Name (Choice)
1572 and then Is_Type (Entity (Choice))
1573 and then Base_Type (Entity (Choice)) = Base_Type (Index_Typ)
1578 Analyze_And_Resolve (Choice, Index_Typ);
1585 -- Create a scope in which to introduce an index, which is usually
1586 -- visible in the expression for the component, and needed for its
1589 Ent := New_Internal_Entity (E_Loop, Current_Scope, Loc, 'L');
1590 Set_Etype (Ent, Standard_Void_Type);
1591 Set_Parent (Ent, Parent (N));
1594 Make_Defining_Identifier (Loc,
1595 Chars => Chars (Defining_Identifier (N)));
1597 -- Insert and decorate the index variable in the current scope.
1598 -- The expression has to be analyzed once the index variable is
1599 -- directly visible. Mark the variable as referenced to prevent
1600 -- spurious warnings, given that subsequent uses of its name in the
1601 -- expression will reference the internal (synonym) loop variable.
1604 Set_Etype (Id, Index_Typ);
1605 Set_Ekind (Id, E_Variable);
1606 Set_Scope (Id, Ent);
1607 Set_Referenced (Id);
1609 -- Analyze a copy of the expression, to verify legality. We use
1610 -- a copy because the expression will be analyzed anew when the
1611 -- enclosing aggregate is expanded, and the construct is rewritten
1612 -- as a loop with a new index variable.
1614 Expr := New_Copy_Tree (Expression (N));
1615 Dummy := Resolve_Aggr_Expr (Expr, False);
1617 -- An iterated_component_association may appear in a nested
1618 -- aggregate for a multidimensional structure: preserve the bounds
1619 -- computed for the expression, as well as the anonymous array
1620 -- type generated for it; both are needed during array expansion.
1621 -- This does not work for more than two levels of nesting. ???
1623 if Nkind (Expr) = N_Aggregate then
1624 Set_Aggregate_Bounds (Expression (N), Aggregate_Bounds (Expr));
1625 Set_Etype (Expression (N), Etype (Expr));
1629 end Resolve_Iterated_Component_Association;
1638 Aggr_Low : Node_Id := Empty;
1639 Aggr_High : Node_Id := Empty;
1640 -- The actual low and high bounds of this sub-aggregate
1642 Case_Table_Size : Nat;
1643 -- Contains the size of the case table needed to sort aggregate choices
1645 Choices_Low : Node_Id := Empty;
1646 Choices_High : Node_Id := Empty;
1647 -- The lowest and highest discrete choices values for a named aggregate
1649 Delete_Choice : Boolean;
1650 -- Used when replacing a subtype choice with predicate by a list
1652 Nb_Elements : Uint := Uint_0;
1653 -- The number of elements in a positional aggregate
1655 Nb_Discrete_Choices : Nat := 0;
1656 -- The overall number of discrete choices (not counting others choice)
1658 -- Start of processing for Resolve_Array_Aggregate
1661 -- Ignore junk empty aggregate resulting from parser error
1663 if No (Expressions (N))
1664 and then No (Component_Associations (N))
1665 and then not Null_Record_Present (N)
1670 -- STEP 1: make sure the aggregate is correctly formatted
1672 if Present (Component_Associations (N)) then
1673 Assoc := First (Component_Associations (N));
1674 while Present (Assoc) loop
1675 if Nkind (Assoc) = N_Iterated_Component_Association then
1676 Resolve_Iterated_Component_Association (Assoc, Index_Typ);
1679 Choice := First (Choice_List (Assoc));
1680 Delete_Choice := False;
1681 while Present (Choice) loop
1682 if Nkind (Choice) = N_Others_Choice then
1683 Others_Present := True;
1685 if Choice /= First (Choice_List (Assoc))
1686 or else Present (Next (Choice))
1689 ("OTHERS must appear alone in a choice list", Choice);
1693 if Present (Next (Assoc)) then
1695 ("OTHERS must appear last in an aggregate", Choice);
1699 if Ada_Version = Ada_83
1700 and then Assoc /= First (Component_Associations (N))
1701 and then Nkind_In (Parent (N), N_Assignment_Statement,
1702 N_Object_Declaration)
1705 ("(Ada 83) illegal context for OTHERS choice", N);
1708 elsif Is_Entity_Name (Choice) then
1712 E : constant Entity_Id := Entity (Choice);
1718 if Is_Type (E) and then Has_Predicates (E) then
1719 Freeze_Before (N, E);
1721 if Has_Dynamic_Predicate_Aspect (E) then
1723 ("subtype& has dynamic predicate, not allowed "
1724 & "in aggregate choice", Choice, E);
1726 elsif not Is_OK_Static_Subtype (E) then
1728 ("non-static subtype& has predicate, not allowed "
1729 & "in aggregate choice", Choice, E);
1732 -- If the subtype has a static predicate, replace the
1733 -- original choice with the list of individual values
1734 -- covered by the predicate.
1735 -- This should be deferred to expansion time ???
1737 if Present (Static_Discrete_Predicate (E)) then
1738 Delete_Choice := True;
1741 P := First (Static_Discrete_Predicate (E));
1742 while Present (P) loop
1744 Set_Sloc (C, Sloc (Choice));
1745 Append_To (New_Cs, C);
1749 Insert_List_After (Choice, New_Cs);
1755 Nb_Choices := Nb_Choices + 1;
1758 C : constant Node_Id := Choice;
1763 if Delete_Choice then
1765 Nb_Choices := Nb_Choices - 1;
1766 Delete_Choice := False;
1775 -- At this point we know that the others choice, if present, is by
1776 -- itself and appears last in the aggregate. Check if we have mixed
1777 -- positional and discrete associations (other than the others choice).
1779 if Present (Expressions (N))
1780 and then (Nb_Choices > 1
1781 or else (Nb_Choices = 1 and then not Others_Present))
1784 ("named association cannot follow positional association",
1785 First (Choice_List (First (Component_Associations (N)))));
1789 -- Test for the validity of an others choice if present
1791 if Others_Present and then not Others_Allowed then
1793 ("OTHERS choice not allowed here",
1794 First (Choices (First (Component_Associations (N)))));
1798 -- Protect against cascaded errors
1800 if Etype (Index_Typ) = Any_Type then
1804 -- STEP 2: Process named components
1806 if No (Expressions (N)) then
1807 if Others_Present then
1808 Case_Table_Size := Nb_Choices - 1;
1810 Case_Table_Size := Nb_Choices;
1814 function Empty_Range (A : Node_Id) return Boolean;
1815 -- If an association covers an empty range, some warnings on the
1816 -- expression of the association can be disabled.
1822 function Empty_Range (A : Node_Id) return Boolean is
1823 R : constant Node_Id := First (Choices (A));
1825 return No (Next (R))
1826 and then Nkind (R) = N_Range
1827 and then Compile_Time_Compare
1828 (Low_Bound (R), High_Bound (R), False) = GT;
1835 -- Denote the lowest and highest values in an aggregate choice
1837 S_Low : Node_Id := Empty;
1838 S_High : Node_Id := Empty;
1839 -- if a choice in an aggregate is a subtype indication these
1840 -- denote the lowest and highest values of the subtype
1842 Table : Case_Table_Type (1 .. Case_Table_Size);
1843 -- Used to sort all the different choice values
1845 Single_Choice : Boolean;
1846 -- Set to true every time there is a single discrete choice in a
1847 -- discrete association
1849 Prev_Nb_Discrete_Choices : Nat;
1850 -- Used to keep track of the number of discrete choices in the
1851 -- current association.
1853 Errors_Posted_On_Choices : Boolean := False;
1854 -- Keeps track of whether any choices have semantic errors
1856 -- Start of processing for Step_2
1859 -- STEP 2 (A): Check discrete choices validity
1861 Assoc := First (Component_Associations (N));
1862 while Present (Assoc) loop
1863 Prev_Nb_Discrete_Choices := Nb_Discrete_Choices;
1864 Choice := First (Choice_List (Assoc));
1869 if Nkind (Choice) = N_Others_Choice then
1870 Single_Choice := False;
1873 -- Test for subtype mark without constraint
1875 elsif Is_Entity_Name (Choice) and then
1876 Is_Type (Entity (Choice))
1878 if Base_Type (Entity (Choice)) /= Index_Base then
1880 ("invalid subtype mark in aggregate choice",
1885 -- Case of subtype indication
1887 elsif Nkind (Choice) = N_Subtype_Indication then
1888 Resolve_Discrete_Subtype_Indication (Choice, Index_Base);
1890 if Has_Dynamic_Predicate_Aspect
1891 (Entity (Subtype_Mark (Choice)))
1894 ("subtype& has dynamic predicate, "
1895 & "not allowed in aggregate choice",
1896 Choice, Entity (Subtype_Mark (Choice)));
1899 -- Does the subtype indication evaluation raise CE?
1901 Get_Index_Bounds (Subtype_Mark (Choice), S_Low, S_High);
1902 Get_Index_Bounds (Choice, Low, High);
1903 Check_Bounds (S_Low, S_High, Low, High);
1905 -- Case of range or expression
1908 Resolve (Choice, Index_Base);
1909 Check_Unset_Reference (Choice);
1910 Check_Non_Static_Context (Choice);
1912 -- If semantic errors were posted on the choice, then
1913 -- record that for possible early return from later
1914 -- processing (see handling of enumeration choices).
1916 if Error_Posted (Choice) then
1917 Errors_Posted_On_Choices := True;
1920 -- Do not range check a choice. This check is redundant
1921 -- since this test is already done when we check that the
1922 -- bounds of the array aggregate are within range.
1924 Set_Do_Range_Check (Choice, False);
1927 -- If we could not resolve the discrete choice stop here
1929 if Etype (Choice) = Any_Type then
1932 -- If the discrete choice raises CE get its original bounds
1934 elsif Nkind (Choice) = N_Raise_Constraint_Error then
1935 Set_Raises_Constraint_Error (N);
1936 Get_Index_Bounds (Original_Node (Choice), Low, High);
1938 -- Otherwise get its bounds as usual
1941 Get_Index_Bounds (Choice, Low, High);
1944 if (Dynamic_Or_Null_Range (Low, High)
1945 or else (Nkind (Choice) = N_Subtype_Indication
1947 Dynamic_Or_Null_Range (S_Low, S_High)))
1948 and then Nb_Choices /= 1
1951 ("dynamic or empty choice in aggregate "
1952 & "must be the only choice", Choice);
1956 if not (All_Composite_Constraints_Static (Low)
1957 and then All_Composite_Constraints_Static (High)
1958 and then All_Composite_Constraints_Static (S_Low)
1959 and then All_Composite_Constraints_Static (S_High))
1961 Check_Restriction (No_Dynamic_Sized_Objects, Choice);
1964 Nb_Discrete_Choices := Nb_Discrete_Choices + 1;
1965 Table (Nb_Discrete_Choices).Lo := Low;
1966 Table (Nb_Discrete_Choices).Hi := High;
1967 Table (Nb_Discrete_Choices).Choice := Choice;
1973 -- Check if we have a single discrete choice and whether
1974 -- this discrete choice specifies a single value.
1977 (Nb_Discrete_Choices = Prev_Nb_Discrete_Choices + 1)
1978 and then (Low = High);
1984 -- Ada 2005 (AI-231)
1986 if Ada_Version >= Ada_2005
1987 and then Known_Null (Expression (Assoc))
1988 and then not Empty_Range (Assoc)
1990 Check_Can_Never_Be_Null (Etype (N), Expression (Assoc));
1993 -- Ada 2005 (AI-287): In case of default initialized component
1994 -- we delay the resolution to the expansion phase.
1996 if Box_Present (Assoc) then
1998 -- Ada 2005 (AI-287): In case of default initialization of a
1999 -- component the expander will generate calls to the
2000 -- corresponding initialization subprogram. We need to call
2001 -- Resolve_Aggr_Expr to check the rules about
2004 if not Resolve_Aggr_Expr
2005 (Assoc, Single_Elmt => Single_Choice)
2010 elsif Nkind (Assoc) = N_Iterated_Component_Association then
2011 null; -- handled above, in a loop context.
2013 elsif not Resolve_Aggr_Expr
2014 (Expression (Assoc), Single_Elmt => Single_Choice)
2018 -- Check incorrect use of dynamically tagged expression
2020 -- We differentiate here two cases because the expression may
2021 -- not be decorated. For example, the analysis and resolution
2022 -- of the expression associated with the others choice will be
2023 -- done later with the full aggregate. In such case we
2024 -- duplicate the expression tree to analyze the copy and
2025 -- perform the required check.
2027 elsif not Present (Etype (Expression (Assoc))) then
2029 Save_Analysis : constant Boolean := Full_Analysis;
2030 Expr : constant Node_Id :=
2031 New_Copy_Tree (Expression (Assoc));
2034 Expander_Mode_Save_And_Set (False);
2035 Full_Analysis := False;
2037 -- Analyze the expression, making sure it is properly
2038 -- attached to the tree before we do the analysis.
2040 Set_Parent (Expr, Parent (Expression (Assoc)));
2043 -- Compute its dimensions now, rather than at the end of
2044 -- resolution, because in the case of multidimensional
2045 -- aggregates subsequent expansion may lead to spurious
2048 Check_Expression_Dimensions (Expr, Component_Typ);
2050 -- If the expression is a literal, propagate this info
2051 -- to the expression in the association, to enable some
2052 -- optimizations downstream.
2054 if Is_Entity_Name (Expr)
2055 and then Present (Entity (Expr))
2056 and then Ekind (Entity (Expr)) = E_Enumeration_Literal
2059 (Expression (Assoc), Component_Typ);
2062 Full_Analysis := Save_Analysis;
2063 Expander_Mode_Restore;
2065 if Is_Tagged_Type (Etype (Expr)) then
2066 Check_Dynamically_Tagged_Expression
2068 Typ => Component_Type (Etype (N)),
2073 elsif Is_Tagged_Type (Etype (Expression (Assoc))) then
2074 Check_Dynamically_Tagged_Expression
2075 (Expr => Expression (Assoc),
2076 Typ => Component_Type (Etype (N)),
2083 -- If aggregate contains more than one choice then these must be
2084 -- static. Check for duplicate and missing values.
2086 -- Note: there is duplicated code here wrt Check_Choice_Set in
2087 -- the body of Sem_Case, and it is possible we could just reuse
2088 -- that procedure. To be checked ???
2090 if Nb_Discrete_Choices > 1 then
2091 Check_Choices : declare
2093 -- Location of choice for messages
2097 -- High end of one range and Low end of the next. Should be
2098 -- contiguous if there is no hole in the list of values.
2102 -- End points of duplicated range
2104 Missing_Or_Duplicates : Boolean := False;
2105 -- Set True if missing or duplicate choices found
2107 procedure Output_Bad_Choices (Lo, Hi : Uint; C : Node_Id);
2108 -- Output continuation message with a representation of the
2109 -- bounds (just Lo if Lo = Hi, else Lo .. Hi). C is the
2110 -- choice node where the message is to be posted.
2112 ------------------------
2113 -- Output_Bad_Choices --
2114 ------------------------
2116 procedure Output_Bad_Choices (Lo, Hi : Uint; C : Node_Id) is
2118 -- Enumeration type case
2120 if Is_Enumeration_Type (Index_Typ) then
2122 Chars (Get_Enum_Lit_From_Pos (Index_Typ, Lo, Loc));
2124 Chars (Get_Enum_Lit_From_Pos (Index_Typ, Hi, Loc));
2127 Error_Msg_N ("\\ %!", C);
2129 Error_Msg_N ("\\ % .. %!", C);
2132 -- Integer types case
2135 Error_Msg_Uint_1 := Lo;
2136 Error_Msg_Uint_2 := Hi;
2139 Error_Msg_N ("\\ ^!", C);
2141 Error_Msg_N ("\\ ^ .. ^!", C);
2144 end Output_Bad_Choices;
2146 -- Start of processing for Check_Choices
2149 Sort_Case_Table (Table);
2151 -- First we do a quick linear loop to find out if we have
2152 -- any duplicates or missing entries (usually we have a
2153 -- legal aggregate, so this will get us out quickly).
2155 for J in 1 .. Nb_Discrete_Choices - 1 loop
2156 Hi_Val := Expr_Value (Table (J).Hi);
2157 Lo_Val := Expr_Value (Table (J + 1).Lo);
2160 or else (Lo_Val > Hi_Val + 1
2161 and then not Others_Present)
2163 Missing_Or_Duplicates := True;
2168 -- If we have missing or duplicate entries, first fill in
2169 -- the Highest entries to make life easier in the following
2170 -- loops to detect bad entries.
2172 if Missing_Or_Duplicates then
2173 Table (1).Highest := Expr_Value (Table (1).Hi);
2175 for J in 2 .. Nb_Discrete_Choices loop
2176 Table (J).Highest :=
2178 (Table (J - 1).Highest, Expr_Value (Table (J).Hi));
2181 -- Loop through table entries to find duplicate indexes
2183 for J in 2 .. Nb_Discrete_Choices loop
2184 Lo_Val := Expr_Value (Table (J).Lo);
2185 Hi_Val := Expr_Value (Table (J).Hi);
2187 -- Case where we have duplicates (the lower bound of
2188 -- this choice is less than or equal to the highest
2189 -- high bound found so far).
2191 if Lo_Val <= Table (J - 1).Highest then
2193 -- We move backwards looking for duplicates. We can
2194 -- abandon this loop as soon as we reach a choice
2195 -- highest value that is less than Lo_Val.
2197 for K in reverse 1 .. J - 1 loop
2198 exit when Table (K).Highest < Lo_Val;
2200 -- Here we may have duplicates between entries
2201 -- for K and J. Get range of duplicates.
2204 UI_Max (Lo_Val, Expr_Value (Table (K).Lo));
2206 UI_Min (Hi_Val, Expr_Value (Table (K).Hi));
2208 -- Nothing to do if duplicate range is null
2210 if Lo_Dup > Hi_Dup then
2213 -- Otherwise place proper message
2216 -- We place message on later choice, with a
2217 -- line reference to the earlier choice.
2219 if Sloc (Table (J).Choice) <
2220 Sloc (Table (K).Choice)
2222 Choice := Table (K).Choice;
2223 Error_Msg_Sloc := Sloc (Table (J).Choice);
2225 Choice := Table (J).Choice;
2226 Error_Msg_Sloc := Sloc (Table (K).Choice);
2229 if Lo_Dup = Hi_Dup then
2231 ("index value in array aggregate "
2232 & "duplicates the one given#!", Choice);
2235 ("index values in array aggregate "
2236 & "duplicate those given#!", Choice);
2239 Output_Bad_Choices (Lo_Dup, Hi_Dup, Choice);
2245 -- Loop through entries in table to find missing indexes.
2246 -- Not needed if others, since missing impossible.
2248 if not Others_Present then
2249 for J in 2 .. Nb_Discrete_Choices loop
2250 Lo_Val := Expr_Value (Table (J).Lo);
2251 Hi_Val := Table (J - 1).Highest;
2253 if Lo_Val > Hi_Val + 1 then
2256 Error_Node : Node_Id;
2259 -- If the choice is the bound of a range in
2260 -- a subtype indication, it is not in the
2261 -- source lists for the aggregate itself, so
2262 -- post the error on the aggregate. Otherwise
2263 -- post it on choice itself.
2265 Choice := Table (J).Choice;
2267 if Is_List_Member (Choice) then
2268 Error_Node := Choice;
2273 if Hi_Val + 1 = Lo_Val - 1 then
2275 ("missing index value "
2276 & "in array aggregate!", Error_Node);
2279 ("missing index values "
2280 & "in array aggregate!", Error_Node);
2284 (Hi_Val + 1, Lo_Val - 1, Error_Node);
2290 -- If either missing or duplicate values, return failure
2292 Set_Etype (N, Any_Composite);
2298 -- STEP 2 (B): Compute aggregate bounds and min/max choices values
2300 if Nb_Discrete_Choices > 0 then
2301 Choices_Low := Table (1).Lo;
2302 Choices_High := Table (Nb_Discrete_Choices).Hi;
2305 -- If Others is present, then bounds of aggregate come from the
2306 -- index constraint (not the choices in the aggregate itself).
2308 if Others_Present then
2309 Get_Index_Bounds (Index_Constr, Aggr_Low, Aggr_High);
2311 -- Abandon processing if either bound is already signalled as
2312 -- an error (prevents junk cascaded messages and blow ups).
2314 if Nkind (Aggr_Low) = N_Error
2316 Nkind (Aggr_High) = N_Error
2321 -- No others clause present
2324 -- Special processing if others allowed and not present. This
2325 -- means that the bounds of the aggregate come from the index
2326 -- constraint (and the length must match).
2328 if Others_Allowed then
2329 Get_Index_Bounds (Index_Constr, Aggr_Low, Aggr_High);
2331 -- Abandon processing if either bound is already signalled
2332 -- as an error (stop junk cascaded messages and blow ups).
2334 if Nkind (Aggr_Low) = N_Error
2336 Nkind (Aggr_High) = N_Error
2341 -- If others allowed, and no others present, then the array
2342 -- should cover all index values. If it does not, we will
2343 -- get a length check warning, but there is two cases where
2344 -- an additional warning is useful:
2346 -- If we have no positional components, and the length is
2347 -- wrong (which we can tell by others being allowed with
2348 -- missing components), and the index type is an enumeration
2349 -- type, then issue appropriate warnings about these missing
2350 -- components. They are only warnings, since the aggregate
2351 -- is fine, it's just the wrong length. We skip this check
2352 -- for standard character types (since there are no literals
2353 -- and it is too much trouble to concoct them), and also if
2354 -- any of the bounds have values that are not known at
2357 -- Another case warranting a warning is when the length
2358 -- is right, but as above we have an index type that is
2359 -- an enumeration, and the bounds do not match. This is a
2360 -- case where dubious sliding is allowed and we generate a
2361 -- warning that the bounds do not match.
2363 if No (Expressions (N))
2364 and then Nkind (Index) = N_Range
2365 and then Is_Enumeration_Type (Etype (Index))
2366 and then not Is_Standard_Character_Type (Etype (Index))
2367 and then Compile_Time_Known_Value (Aggr_Low)
2368 and then Compile_Time_Known_Value (Aggr_High)
2369 and then Compile_Time_Known_Value (Choices_Low)
2370 and then Compile_Time_Known_Value (Choices_High)
2372 -- If any of the expressions or range bounds in choices
2373 -- have semantic errors, then do not attempt further
2374 -- resolution, to prevent cascaded errors.
2376 if Errors_Posted_On_Choices then
2381 ALo : constant Node_Id := Expr_Value_E (Aggr_Low);
2382 AHi : constant Node_Id := Expr_Value_E (Aggr_High);
2383 CLo : constant Node_Id := Expr_Value_E (Choices_Low);
2384 CHi : constant Node_Id := Expr_Value_E (Choices_High);
2389 -- Warning case 1, missing values at start/end. Only
2390 -- do the check if the number of entries is too small.
2392 if (Enumeration_Pos (CHi) - Enumeration_Pos (CLo))
2394 (Enumeration_Pos (AHi) - Enumeration_Pos (ALo))
2397 ("missing index value(s) in array aggregate??",
2400 -- Output missing value(s) at start
2402 if Chars (ALo) /= Chars (CLo) then
2405 if Chars (ALo) = Chars (Ent) then
2406 Error_Msg_Name_1 := Chars (ALo);
2407 Error_Msg_N ("\ %??", N);
2409 Error_Msg_Name_1 := Chars (ALo);
2410 Error_Msg_Name_2 := Chars (Ent);
2411 Error_Msg_N ("\ % .. %??", N);
2415 -- Output missing value(s) at end
2417 if Chars (AHi) /= Chars (CHi) then
2420 if Chars (AHi) = Chars (Ent) then
2421 Error_Msg_Name_1 := Chars (Ent);
2422 Error_Msg_N ("\ %??", N);
2424 Error_Msg_Name_1 := Chars (Ent);
2425 Error_Msg_Name_2 := Chars (AHi);
2426 Error_Msg_N ("\ % .. %??", N);
2430 -- Warning case 2, dubious sliding. The First_Subtype
2431 -- test distinguishes between a constrained type where
2432 -- sliding is not allowed (so we will get a warning
2433 -- later that Constraint_Error will be raised), and
2434 -- the unconstrained case where sliding is permitted.
2436 elsif (Enumeration_Pos (CHi) - Enumeration_Pos (CLo))
2438 (Enumeration_Pos (AHi) - Enumeration_Pos (ALo))
2439 and then Chars (ALo) /= Chars (CLo)
2441 not Is_Constrained (First_Subtype (Etype (N)))
2444 ("bounds of aggregate do not match target??", N);
2450 -- If no others, aggregate bounds come from aggregate
2452 Aggr_Low := Choices_Low;
2453 Aggr_High := Choices_High;
2457 -- STEP 3: Process positional components
2460 -- STEP 3 (A): Process positional elements
2462 Expr := First (Expressions (N));
2463 Nb_Elements := Uint_0;
2464 while Present (Expr) loop
2465 Nb_Elements := Nb_Elements + 1;
2467 -- Ada 2005 (AI-231)
2469 if Ada_Version >= Ada_2005 and then Known_Null (Expr) then
2470 Check_Can_Never_Be_Null (Etype (N), Expr);
2473 if not Resolve_Aggr_Expr (Expr, Single_Elmt => True) then
2477 -- Check incorrect use of dynamically tagged expression
2479 if Is_Tagged_Type (Etype (Expr)) then
2480 Check_Dynamically_Tagged_Expression
2482 Typ => Component_Type (Etype (N)),
2489 if Others_Present then
2490 Assoc := Last (Component_Associations (N));
2492 -- Ada 2005 (AI-231)
2494 if Ada_Version >= Ada_2005 and then Known_Null (Assoc) then
2495 Check_Can_Never_Be_Null (Etype (N), Expression (Assoc));
2498 -- Ada 2005 (AI-287): In case of default initialized component,
2499 -- we delay the resolution to the expansion phase.
2501 if Box_Present (Assoc) then
2503 -- Ada 2005 (AI-287): In case of default initialization of a
2504 -- component the expander will generate calls to the
2505 -- corresponding initialization subprogram. We need to call
2506 -- Resolve_Aggr_Expr to check the rules about
2509 if not Resolve_Aggr_Expr (Assoc, Single_Elmt => False) then
2513 elsif not Resolve_Aggr_Expr (Expression (Assoc),
2514 Single_Elmt => False)
2518 -- Check incorrect use of dynamically tagged expression. The
2519 -- expression of the others choice has not been resolved yet.
2520 -- In order to diagnose the semantic error we create a duplicate
2521 -- tree to analyze it and perform the check.
2525 Save_Analysis : constant Boolean := Full_Analysis;
2526 Expr : constant Node_Id :=
2527 New_Copy_Tree (Expression (Assoc));
2530 Expander_Mode_Save_And_Set (False);
2531 Full_Analysis := False;
2533 Full_Analysis := Save_Analysis;
2534 Expander_Mode_Restore;
2536 if Is_Tagged_Type (Etype (Expr)) then
2537 Check_Dynamically_Tagged_Expression
2539 Typ => Component_Type (Etype (N)),
2546 -- STEP 3 (B): Compute the aggregate bounds
2548 if Others_Present then
2549 Get_Index_Bounds (Index_Constr, Aggr_Low, Aggr_High);
2552 if Others_Allowed then
2553 Get_Index_Bounds (Index_Constr, Aggr_Low, Discard);
2555 Aggr_Low := Index_Typ_Low;
2558 Aggr_High := Add (Nb_Elements - 1, To => Aggr_Low);
2559 Check_Bound (Index_Base_High, Aggr_High);
2563 -- STEP 4: Perform static aggregate checks and save the bounds
2567 Check_Bounds (Index_Typ_Low, Index_Typ_High, Aggr_Low, Aggr_High);
2568 Check_Bounds (Index_Base_Low, Index_Base_High, Aggr_Low, Aggr_High);
2572 if Others_Present and then Nb_Discrete_Choices > 0 then
2573 Check_Bounds (Aggr_Low, Aggr_High, Choices_Low, Choices_High);
2574 Check_Bounds (Index_Typ_Low, Index_Typ_High,
2575 Choices_Low, Choices_High);
2576 Check_Bounds (Index_Base_Low, Index_Base_High,
2577 Choices_Low, Choices_High);
2581 elsif Others_Present and then Nb_Elements > 0 then
2582 Check_Length (Aggr_Low, Aggr_High, Nb_Elements);
2583 Check_Length (Index_Typ_Low, Index_Typ_High, Nb_Elements);
2584 Check_Length (Index_Base_Low, Index_Base_High, Nb_Elements);
2587 if Raises_Constraint_Error (Aggr_Low)
2588 or else Raises_Constraint_Error (Aggr_High)
2590 Set_Raises_Constraint_Error (N);
2593 Aggr_Low := Duplicate_Subexpr (Aggr_Low);
2595 -- Do not duplicate Aggr_High if Aggr_High = Aggr_Low + Nb_Elements
2596 -- since the addition node returned by Add is not yet analyzed. Attach
2597 -- to tree and analyze first. Reset analyzed flag to ensure it will get
2598 -- analyzed when it is a literal bound whose type must be properly set.
2600 if Others_Present or else Nb_Discrete_Choices > 0 then
2601 Aggr_High := Duplicate_Subexpr (Aggr_High);
2603 if Etype (Aggr_High) = Universal_Integer then
2604 Set_Analyzed (Aggr_High, False);
2608 -- If the aggregate already has bounds attached to it, it means this is
2609 -- a positional aggregate created as an optimization by
2610 -- Exp_Aggr.Convert_To_Positional, so we don't want to change those
2613 if Present (Aggregate_Bounds (N)) and then not Others_Allowed then
2614 Aggr_Low := Low_Bound (Aggregate_Bounds (N));
2615 Aggr_High := High_Bound (Aggregate_Bounds (N));
2618 Set_Aggregate_Bounds
2619 (N, Make_Range (Loc, Low_Bound => Aggr_Low, High_Bound => Aggr_High));
2621 -- The bounds may contain expressions that must be inserted upwards.
2622 -- Attach them fully to the tree. After analysis, remove side effects
2623 -- from upper bound, if still needed.
2625 Set_Parent (Aggregate_Bounds (N), N);
2626 Analyze_And_Resolve (Aggregate_Bounds (N), Index_Typ);
2627 Check_Unset_Reference (Aggregate_Bounds (N));
2629 if not Others_Present and then Nb_Discrete_Choices = 0 then
2631 (Aggregate_Bounds (N),
2632 Duplicate_Subexpr (High_Bound (Aggregate_Bounds (N))));
2635 -- Check the dimensions of each component in the array aggregate
2637 Analyze_Dimension_Array_Aggregate (N, Component_Typ);
2640 end Resolve_Array_Aggregate;
2642 ---------------------------------
2643 -- Resolve_Container_Aggregate --
2644 ---------------------------------
2646 procedure Resolve_Container_Aggregate (N : Node_Id; Typ : Entity_Id) is
2647 procedure Resolve_Iterated_Component_Association
2649 Key_Type : Entity_Id;
2650 Elmt_Type : Entity_Id);
2651 -- Resolve choices and expression in an iterated component
2652 -- association. This is similar but not identical to the handling
2653 -- of this construct in an array aggregate.
2654 -- For a named container, the type of each choice must be compatible
2655 -- with the key type. For a positional container the choice must be
2656 -- a subtype indication or an iterator specification that determines
2659 Asp : constant Node_Id := Find_Value_Of_Aspect (Typ, Aspect_Aggregate);
2661 Empty_Subp : Node_Id := Empty;
2662 Add_Named_Subp : Node_Id := Empty;
2663 Add_Unnamed_Subp : Node_Id := Empty;
2664 New_Indexed_Subp : Node_Id := Empty;
2665 Assign_Indexed_Subp : Node_Id := Empty;
2667 --------------------------------------------
2668 -- Resolve_Iterated_Component_Association --
2669 --------------------------------------------
2671 procedure Resolve_Iterated_Component_Association
2673 Key_Type : Entity_Id;
2674 Elmt_Type : Entity_Id)
2683 if Present (Iterator_Specification (Comp)) then
2684 Error_Msg_N ("element iterator ins aggregate Forthcoming", N);
2688 Choice := First (Discrete_Choices (Comp));
2690 while Present (Choice) loop
2693 -- Choice can be a subtype name, a range, or an expression
2695 if Is_Entity_Name (Choice)
2696 and then Is_Type (Entity (Choice))
2697 and then Base_Type (Entity (Choice)) = Base_Type (Key_Type)
2701 elsif Present (Key_Type) then
2702 Analyze_And_Resolve (Choice, Key_Type);
2705 Typ := Etype (Choice); -- assume unique for now
2711 -- Create a scope in which to introduce an index, which is usually
2712 -- visible in the expression for the component, and needed for its
2715 Ent := New_Internal_Entity (E_Loop, Current_Scope, Sloc (Comp), 'L');
2716 Set_Etype (Ent, Standard_Void_Type);
2717 Set_Parent (Ent, Parent (Comp));
2720 Make_Defining_Identifier (Sloc (Comp),
2721 Chars => Chars (Defining_Identifier (Comp)));
2723 -- Insert and decorate the loop variable in the current scope.
2724 -- The expression has to be analyzed once the loop variable is
2725 -- directly visible. Mark the variable as referenced to prevent
2726 -- spurious warnings, given that subsequent uses of its name in the
2727 -- expression will reference the internal (synonym) loop variable.
2730 if No (Key_Type) then
2731 Set_Etype (Id, Typ);
2733 Set_Etype (Id, Key_Type);
2736 Set_Ekind (Id, E_Variable);
2737 Set_Scope (Id, Ent);
2738 Set_Referenced (Id);
2740 -- Analyze a copy of the expression, to verify legality. We use
2741 -- a copy because the expression will be analyzed anew when the
2742 -- enclosing aggregate is expanded, and the construct is rewritten
2743 -- as a loop with a new index variable.
2745 Expr := New_Copy_Tree (Expression (Comp));
2746 Preanalyze_And_Resolve (Expr, Elmt_Type);
2748 end Resolve_Iterated_Component_Association;
2751 pragma Assert (Nkind (Asp) = N_Aggregate);
2754 Parse_Aspect_Aggregate (Asp,
2755 Empty_Subp, Add_Named_Subp, Add_Unnamed_Subp,
2756 New_Indexed_Subp, Assign_Indexed_Subp);
2758 if Present (Add_Unnamed_Subp) then
2760 Elmt_Type : constant Entity_Id :=
2762 (First_Formal (Entity (Add_Unnamed_Subp))));
2766 if Present (Expressions (N)) then
2767 -- positional aggregate
2769 Comp := First (Expressions (N));
2770 while Present (Comp) loop
2771 Analyze_And_Resolve (Comp, Elmt_Type);
2776 -- Empty aggregate, to be replaced by Empty during
2777 -- expansion, or iterated component association.
2779 if Present (Component_Associations (N)) then
2781 Comp : Node_Id := First (Component_Associations (N));
2783 while Present (Comp) loop
2785 N_Iterated_Component_Association
2787 Error_Msg_N ("illegal component association "
2788 & "for unnamed container aggregate", Comp);
2791 Resolve_Iterated_Component_Association
2792 (Comp, Empty, Elmt_Type);
2801 elsif Present (Add_Named_Subp) then
2803 -- Retrieves types of container, key, and element from the
2804 -- specified insertion procedure.
2806 Container : constant Entity_Id :=
2807 First_Formal (Entity (Add_Named_Subp));
2808 Key_Type : constant Entity_Id := Etype (Next_Formal (Container));
2809 Elmt_Type : constant Entity_Id :=
2810 Etype (Next_Formal (Next_Formal (Container)));
2815 Comp := First (Component_Associations (N));
2816 while Present (Comp) loop
2817 if Nkind (Comp) = N_Component_Association then
2818 Choice := First (Choices (Comp));
2820 while Present (Choice) loop
2821 Analyze_And_Resolve (Choice, Key_Type);
2825 Analyze_And_Resolve (Expression (Comp), Elmt_Type);
2827 elsif Nkind (Comp) = N_Iterated_Component_Association then
2828 Resolve_Iterated_Component_Association
2829 (Comp, Key_Type, Elmt_Type);
2836 Error_Msg_N ("indexed aggregates are forthcoming", N);
2838 end Resolve_Container_Aggregate;
2840 -----------------------------
2841 -- Resolve_Delta_Aggregate --
2842 -----------------------------
2844 procedure Resolve_Delta_Aggregate (N : Node_Id; Typ : Entity_Id) is
2845 Base : constant Node_Id := Expression (N);
2848 if Ada_Version < Ada_2020 then
2849 Error_Msg_N ("delta_aggregate is an Ada 202x feature", N);
2850 Error_Msg_N ("\compile with -gnat2020", N);
2853 if not Is_Composite_Type (Typ) then
2854 Error_Msg_N ("not a composite type", N);
2857 Analyze_And_Resolve (Base, Typ);
2859 if Is_Array_Type (Typ) then
2860 Resolve_Delta_Array_Aggregate (N, Typ);
2862 Resolve_Delta_Record_Aggregate (N, Typ);
2866 end Resolve_Delta_Aggregate;
2868 -----------------------------------
2869 -- Resolve_Delta_Array_Aggregate --
2870 -----------------------------------
2872 procedure Resolve_Delta_Array_Aggregate (N : Node_Id; Typ : Entity_Id) is
2873 Deltas : constant List_Id := Component_Associations (N);
2874 Index_Type : constant Entity_Id := Etype (First_Index (Typ));
2880 Assoc := First (Deltas);
2881 while Present (Assoc) loop
2882 if Nkind (Assoc) = N_Iterated_Component_Association then
2883 Choice := First (Choice_List (Assoc));
2884 while Present (Choice) loop
2885 if Nkind (Choice) = N_Others_Choice then
2887 ("others not allowed in delta aggregate", Choice);
2890 Analyze_And_Resolve (Choice, Index_Type);
2897 Id : constant Entity_Id := Defining_Identifier (Assoc);
2898 Ent : constant Entity_Id :=
2900 (E_Loop, Current_Scope, Sloc (Assoc), 'L');
2903 Set_Etype (Ent, Standard_Void_Type);
2904 Set_Parent (Ent, Assoc);
2906 if No (Scope (Id)) then
2908 Set_Etype (Id, Index_Type);
2909 Set_Ekind (Id, E_Variable);
2910 Set_Scope (Id, Ent);
2915 (New_Copy_Tree (Expression (Assoc)), Component_Type (Typ));
2920 Choice := First (Choice_List (Assoc));
2921 while Present (Choice) loop
2922 if Nkind (Choice) = N_Others_Choice then
2924 ("others not allowed in delta aggregate", Choice);
2929 if Is_Entity_Name (Choice)
2930 and then Is_Type (Entity (Choice))
2932 -- Choice covers a range of values
2934 if Base_Type (Entity (Choice)) /=
2935 Base_Type (Index_Type)
2938 ("choice does mat match index type of",
2942 Resolve (Choice, Index_Type);
2949 Analyze_And_Resolve (Expression (Assoc), Component_Type (Typ));
2954 end Resolve_Delta_Array_Aggregate;
2956 ------------------------------------
2957 -- Resolve_Delta_Record_Aggregate --
2958 ------------------------------------
2960 procedure Resolve_Delta_Record_Aggregate (N : Node_Id; Typ : Entity_Id) is
2962 -- Variables used to verify that discriminant-dependent components
2963 -- appear in the same variant.
2965 Comp_Ref : Entity_Id := Empty; -- init to avoid warning
2968 procedure Check_Variant (Id : Entity_Id);
2969 -- If a given component of the delta aggregate appears in a variant
2970 -- part, verify that it is within the same variant as that of previous
2971 -- specified variant components of the delta.
2973 function Get_Component (Nam : Node_Id) return Entity_Id;
2974 -- Locate component with a given name and return it. If none found then
2975 -- report error and return Empty.
2977 function Nested_In (V1 : Node_Id; V2 : Node_Id) return Boolean;
2978 -- Determine whether variant V1 is within variant V2
2980 function Variant_Depth (N : Node_Id) return Integer;
2981 -- Determine the distance of a variant to the enclosing type
2984 --------------------
2986 --------------------
2988 procedure Check_Variant (Id : Entity_Id) is
2990 Comp_Variant : Node_Id;
2993 if not Has_Discriminants (Typ) then
2997 Comp := First_Entity (Typ);
2998 while Present (Comp) loop
2999 exit when Chars (Comp) = Chars (Id);
3000 Next_Component (Comp);
3003 -- Find the variant, if any, whose component list includes the
3004 -- component declaration.
3006 Comp_Variant := Parent (Parent (List_Containing (Parent (Comp))));
3007 if Nkind (Comp_Variant) = N_Variant then
3008 if No (Variant) then
3009 Variant := Comp_Variant;
3012 elsif Variant /= Comp_Variant then
3014 D1 : constant Integer := Variant_Depth (Variant);
3015 D2 : constant Integer := Variant_Depth (Comp_Variant);
3020 (D1 > D2 and then not Nested_In (Variant, Comp_Variant))
3022 (D2 > D1 and then not Nested_In (Comp_Variant, Variant))
3024 pragma Assert (Present (Comp_Ref));
3025 Error_Msg_Node_2 := Comp_Ref;
3027 ("& and & appear in different variants", Id, Comp);
3029 -- Otherwise retain the deeper variant for subsequent tests
3032 Variant := Comp_Variant;
3043 function Get_Component (Nam : Node_Id) return Entity_Id is
3047 Comp := First_Entity (Typ);
3048 while Present (Comp) loop
3049 if Chars (Comp) = Chars (Nam) then
3050 if Ekind (Comp) = E_Discriminant then
3051 Error_Msg_N ("delta cannot apply to discriminant", Nam);
3060 Error_Msg_NE ("type& has no component with this name", Nam, Typ);
3068 function Nested_In (V1, V2 : Node_Id) return Boolean is
3073 while Nkind (Par) /= N_Full_Type_Declaration loop
3078 Par := Parent (Par);
3088 function Variant_Depth (N : Node_Id) return Integer is
3095 while Nkind (Par) /= N_Full_Type_Declaration loop
3097 Par := Parent (Par);
3105 Deltas : constant List_Id := Component_Associations (N);
3110 Comp_Type : Entity_Id := Empty; -- init to avoid warning
3112 -- Start of processing for Resolve_Delta_Record_Aggregate
3117 Assoc := First (Deltas);
3118 while Present (Assoc) loop
3119 Choice := First (Choice_List (Assoc));
3120 while Present (Choice) loop
3121 Comp := Get_Component (Choice);
3123 if Present (Comp) then
3124 Check_Variant (Choice);
3126 Comp_Type := Etype (Comp);
3128 -- Decorate the component reference by setting its entity and
3129 -- type, as otherwise backends like GNATprove would have to
3130 -- rediscover this information by themselves.
3132 Set_Entity (Choice, Comp);
3133 Set_Etype (Choice, Comp_Type);
3135 Comp_Type := Any_Type;
3141 pragma Assert (Present (Comp_Type));
3142 Analyze_And_Resolve (Expression (Assoc), Comp_Type);
3145 end Resolve_Delta_Record_Aggregate;
3147 ---------------------------------
3148 -- Resolve_Extension_Aggregate --
3149 ---------------------------------
3151 -- There are two cases to consider:
3153 -- a) If the ancestor part is a type mark, the components needed are the
3154 -- difference between the components of the expected type and the
3155 -- components of the given type mark.
3157 -- b) If the ancestor part is an expression, it must be unambiguous, and
3158 -- once we have its type we can also compute the needed components as in
3159 -- the previous case. In both cases, if the ancestor type is not the
3160 -- immediate ancestor, we have to build this ancestor recursively.
3162 -- In both cases, discriminants of the ancestor type do not play a role in
3163 -- the resolution of the needed components, because inherited discriminants
3164 -- cannot be used in a type extension. As a result we can compute
3165 -- independently the list of components of the ancestor type and of the
3168 procedure Resolve_Extension_Aggregate (N : Node_Id; Typ : Entity_Id) is
3169 A : constant Node_Id := Ancestor_Part (N);
3174 function Valid_Limited_Ancestor (Anc : Node_Id) return Boolean;
3175 -- If the type is limited, verify that the ancestor part is a legal
3176 -- expression (aggregate or function call, including 'Input)) that does
3177 -- not require a copy, as specified in 7.5(2).
3179 function Valid_Ancestor_Type return Boolean;
3180 -- Verify that the type of the ancestor part is a non-private ancestor
3181 -- of the expected type, which must be a type extension.
3183 procedure Transform_BIP_Assignment (Typ : Entity_Id);
3184 -- For an extension aggregate whose ancestor part is a build-in-place
3185 -- call returning a nonlimited type, this is used to transform the
3186 -- assignment to the ancestor part to use a temp.
3188 ----------------------------
3189 -- Valid_Limited_Ancestor --
3190 ----------------------------
3192 function Valid_Limited_Ancestor (Anc : Node_Id) return Boolean is
3194 if Is_Entity_Name (Anc) and then Is_Type (Entity (Anc)) then
3197 -- The ancestor must be a call or an aggregate, but a call may
3198 -- have been expanded into a temporary, so check original node.
3200 elsif Nkind_In (Anc, N_Aggregate,
3201 N_Extension_Aggregate,
3206 elsif Nkind (Original_Node (Anc)) = N_Function_Call then
3209 elsif Nkind (Anc) = N_Attribute_Reference
3210 and then Attribute_Name (Anc) = Name_Input
3214 elsif Nkind (Anc) = N_Qualified_Expression then
3215 return Valid_Limited_Ancestor (Expression (Anc));
3217 elsif Nkind (Anc) = N_Raise_Expression then
3223 end Valid_Limited_Ancestor;
3225 -------------------------
3226 -- Valid_Ancestor_Type --
3227 -------------------------
3229 function Valid_Ancestor_Type return Boolean is
3230 Imm_Type : Entity_Id;
3233 Imm_Type := Base_Type (Typ);
3234 while Is_Derived_Type (Imm_Type) loop
3235 if Etype (Imm_Type) = Base_Type (A_Type) then
3238 -- The base type of the parent type may appear as a private
3239 -- extension if it is declared as such in a parent unit of the
3240 -- current one. For consistency of the subsequent analysis use
3241 -- the partial view for the ancestor part.
3243 elsif Is_Private_Type (Etype (Imm_Type))
3244 and then Present (Full_View (Etype (Imm_Type)))
3245 and then Base_Type (A_Type) = Full_View (Etype (Imm_Type))
3247 A_Type := Etype (Imm_Type);
3250 -- The parent type may be a private extension. The aggregate is
3251 -- legal if the type of the aggregate is an extension of it that
3252 -- is not a private extension.
3254 elsif Is_Private_Type (A_Type)
3255 and then not Is_Private_Type (Imm_Type)
3256 and then Present (Full_View (A_Type))
3257 and then Base_Type (Full_View (A_Type)) = Etype (Imm_Type)
3261 -- The parent type may be a raise expression (which is legal in
3262 -- any expression context).
3264 elsif A_Type = Raise_Type then
3265 A_Type := Etype (Imm_Type);
3269 Imm_Type := Etype (Base_Type (Imm_Type));
3273 -- If previous loop did not find a proper ancestor, report error
3275 Error_Msg_NE ("expect ancestor type of &", A, Typ);
3277 end Valid_Ancestor_Type;
3279 ------------------------------
3280 -- Transform_BIP_Assignment --
3281 ------------------------------
3283 procedure Transform_BIP_Assignment (Typ : Entity_Id) is
3284 Loc : constant Source_Ptr := Sloc (N);
3285 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'Y', A);
3286 Obj_Decl : constant Node_Id :=
3287 Make_Object_Declaration (Loc,
3288 Defining_Identifier => Def_Id,
3289 Constant_Present => True,
3290 Object_Definition => New_Occurrence_Of (Typ, Loc),
3292 Has_Init_Expression => True);
3294 Set_Etype (Def_Id, Typ);
3295 Set_Ancestor_Part (N, New_Occurrence_Of (Def_Id, Loc));
3296 Insert_Action (N, Obj_Decl);
3297 end Transform_BIP_Assignment;
3299 -- Start of processing for Resolve_Extension_Aggregate
3302 -- Analyze the ancestor part and account for the case where it is a
3303 -- parameterless function call.
3306 Check_Parameterless_Call (A);
3308 if Is_Entity_Name (A) and then Is_Type (Entity (A)) then
3310 -- AI05-0115: if the ancestor part is a subtype mark, the ancestor
3311 -- must not have unknown discriminants.
3313 if Has_Unknown_Discriminants (Entity (A)) then
3315 ("aggregate not available for type& whose ancestor "
3316 & "has unknown discriminants", N, Typ);
3320 if not Is_Tagged_Type (Typ) then
3321 Error_Msg_N ("type of extension aggregate must be tagged", N);
3324 elsif Is_Limited_Type (Typ) then
3326 -- Ada 2005 (AI-287): Limited aggregates are allowed
3328 if Ada_Version < Ada_2005 then
3329 Error_Msg_N ("aggregate type cannot be limited", N);
3330 Explain_Limited_Type (Typ, N);
3333 elsif Valid_Limited_Ancestor (A) then
3338 ("limited ancestor part must be aggregate or function call", A);
3341 elsif Is_Class_Wide_Type (Typ) then
3342 Error_Msg_N ("aggregate cannot be of a class-wide type", N);
3346 if Is_Entity_Name (A) and then Is_Type (Entity (A)) then
3347 A_Type := Get_Full_View (Entity (A));
3349 if Valid_Ancestor_Type then
3350 Set_Entity (A, A_Type);
3351 Set_Etype (A, A_Type);
3353 Validate_Ancestor_Part (N);
3354 Resolve_Record_Aggregate (N, Typ);
3357 elsif Nkind (A) /= N_Aggregate then
3358 if Is_Overloaded (A) then
3361 Get_First_Interp (A, I, It);
3362 while Present (It.Typ) loop
3364 -- Consider limited interpretations if Ada 2005 or higher
3366 if Is_Tagged_Type (It.Typ)
3367 and then (Ada_Version >= Ada_2005
3368 or else not Is_Limited_Type (It.Typ))
3370 if A_Type /= Any_Type then
3371 Error_Msg_N ("cannot resolve expression", A);
3378 Get_Next_Interp (I, It);
3381 if A_Type = Any_Type then
3382 if Ada_Version >= Ada_2005 then
3384 ("ancestor part must be of a tagged type", A);
3387 ("ancestor part must be of a nonlimited tagged type", A);
3394 A_Type := Etype (A);
3397 if Valid_Ancestor_Type then
3398 Resolve (A, A_Type);
3399 Check_Unset_Reference (A);
3400 Check_Non_Static_Context (A);
3402 -- The aggregate is illegal if the ancestor expression is a call
3403 -- to a function with a limited unconstrained result, unless the
3404 -- type of the aggregate is a null extension. This restriction
3405 -- was added in AI05-67 to simplify implementation.
3407 if Nkind (A) = N_Function_Call
3408 and then Is_Limited_Type (A_Type)
3409 and then not Is_Null_Extension (Typ)
3410 and then not Is_Constrained (A_Type)
3413 ("type of limited ancestor part must be constrained", A);
3415 -- Reject the use of CPP constructors that leave objects partially
3416 -- initialized. For example:
3418 -- type CPP_Root is tagged limited record ...
3419 -- pragma Import (CPP, CPP_Root);
3421 -- type CPP_DT is new CPP_Root and Iface ...
3422 -- pragma Import (CPP, CPP_DT);
3424 -- type Ada_DT is new CPP_DT with ...
3426 -- Obj : Ada_DT := Ada_DT'(New_CPP_Root with others => <>);
3428 -- Using the constructor of CPP_Root the slots of the dispatch
3429 -- table of CPP_DT cannot be set, and the secondary tag of
3430 -- CPP_DT is unknown.
3432 elsif Nkind (A) = N_Function_Call
3433 and then Is_CPP_Constructor_Call (A)
3434 and then Enclosing_CPP_Parent (Typ) /= A_Type
3437 ("??must use 'C'P'P constructor for type &", A,
3438 Enclosing_CPP_Parent (Typ));
3440 -- The following call is not needed if the previous warning
3441 -- is promoted to an error.
3443 Resolve_Record_Aggregate (N, Typ);
3445 elsif Is_Class_Wide_Type (Etype (A))
3446 and then Nkind (Original_Node (A)) = N_Function_Call
3448 -- If the ancestor part is a dispatching call, it appears
3449 -- statically to be a legal ancestor, but it yields any member
3450 -- of the class, and it is not possible to determine whether
3451 -- it is an ancestor of the extension aggregate (much less
3452 -- which ancestor). It is not possible to determine the
3453 -- components of the extension part.
3455 -- This check implements AI-306, which in fact was motivated by
3456 -- an AdaCore query to the ARG after this test was added.
3458 Error_Msg_N ("ancestor part must be statically tagged", A);
3460 -- We are using the build-in-place protocol, but we can't build
3461 -- in place, because we need to call the function before
3462 -- allocating the aggregate. Could do better for null
3463 -- extensions, and maybe for nondiscriminated types.
3464 -- This is wrong for limited, but those were wrong already.
3466 if not Is_Limited_View (A_Type)
3467 and then Is_Build_In_Place_Function_Call (A)
3469 Transform_BIP_Assignment (A_Type);
3472 Resolve_Record_Aggregate (N, Typ);
3477 Error_Msg_N ("no unique type for this aggregate", A);
3480 Check_Function_Writable_Actuals (N);
3481 end Resolve_Extension_Aggregate;
3483 ------------------------------
3484 -- Resolve_Record_Aggregate --
3485 ------------------------------
3487 procedure Resolve_Record_Aggregate (N : Node_Id; Typ : Entity_Id) is
3488 New_Assoc_List : constant List_Id := New_List;
3489 -- New_Assoc_List is the newly built list of N_Component_Association
3492 Others_Etype : Entity_Id := Empty;
3493 -- This variable is used to save the Etype of the last record component
3494 -- that takes its value from the others choice. Its purpose is:
3496 -- (a) make sure the others choice is useful
3498 -- (b) make sure the type of all the components whose value is
3499 -- subsumed by the others choice are the same.
3501 -- This variable is updated as a side effect of function Get_Value.
3503 Box_Node : Node_Id := Empty;
3504 Is_Box_Present : Boolean := False;
3505 Others_Box : Natural := 0;
3506 -- Ada 2005 (AI-287): Variables used in case of default initialization
3507 -- to provide a functionality similar to Others_Etype. Box_Present
3508 -- indicates that the component takes its default initialization;
3509 -- Others_Box counts the number of components of the current aggregate
3510 -- (which may be a sub-aggregate of a larger one) that are default-
3511 -- initialized. A value of One indicates that an others_box is present.
3512 -- Any larger value indicates that the others_box is not redundant.
3513 -- These variables, similar to Others_Etype, are also updated as a side
3514 -- effect of function Get_Value. Box_Node is used to place a warning on
3515 -- a redundant others_box.
3517 procedure Add_Association
3518 (Component : Entity_Id;
3520 Assoc_List : List_Id;
3521 Is_Box_Present : Boolean := False);
3522 -- Builds a new N_Component_Association node which associates Component
3523 -- to expression Expr and adds it to the association list being built,
3524 -- either New_Assoc_List, or the association being built for an inner
3527 procedure Add_Discriminant_Values
3528 (New_Aggr : Node_Id;
3529 Assoc_List : List_Id);
3530 -- The constraint to a component may be given by a discriminant of the
3531 -- enclosing type, in which case we have to retrieve its value, which is
3532 -- part of the enclosing aggregate. Assoc_List provides the discriminant
3533 -- associations of the current type or of some enclosing record.
3535 function Discriminant_Present (Input_Discr : Entity_Id) return Boolean;
3536 -- If aggregate N is a regular aggregate this routine will return True.
3537 -- Otherwise, if N is an extension aggregate, then Input_Discr denotes
3538 -- a discriminant whose value may already have been specified by N's
3539 -- ancestor part. This routine checks whether this is indeed the case
3540 -- and if so returns False, signaling that no value for Input_Discr
3541 -- should appear in N's aggregate part. Also, in this case, the routine
3542 -- appends to New_Assoc_List the discriminant value specified in the
3545 -- If the aggregate is in a context with expansion delayed, it will be
3546 -- reanalyzed. The inherited discriminant values must not be reinserted
3547 -- in the component list to prevent spurious errors, but they must be
3548 -- present on first analysis to build the proper subtype indications.
3549 -- The flag Inherited_Discriminant is used to prevent the re-insertion.
3551 function Find_Private_Ancestor (Typ : Entity_Id) return Entity_Id;
3552 -- AI05-0115: Find earlier ancestor in the derivation chain that is
3553 -- derived from private view Typ. Whether the aggregate is legal depends
3554 -- on the current visibility of the type as well as that of the parent
3558 (Compon : Entity_Id;
3560 Consider_Others_Choice : Boolean := False) return Node_Id;
3561 -- Given a record component stored in parameter Compon, this function
3562 -- returns its value as it appears in the list From, which is a list
3563 -- of N_Component_Association nodes.
3565 -- If no component association has a choice for the searched component,
3566 -- the value provided by the others choice is returned, if there is one,
3567 -- and Consider_Others_Choice is set to true. Otherwise Empty is
3568 -- returned. If there is more than one component association giving a
3569 -- value for the searched record component, an error message is emitted
3570 -- and the first found value is returned.
3572 -- If Consider_Others_Choice is set and the returned expression comes
3573 -- from the others choice, then Others_Etype is set as a side effect.
3574 -- An error message is emitted if the components taking their value from
3575 -- the others choice do not have same type.
3577 procedure Propagate_Discriminants
3579 Assoc_List : List_Id);
3580 -- Nested components may themselves be discriminated types constrained
3581 -- by outer discriminants, whose values must be captured before the
3582 -- aggregate is expanded into assignments.
3584 procedure Resolve_Aggr_Expr (Expr : Node_Id; Component : Entity_Id);
3585 -- Analyzes and resolves expression Expr against the Etype of the
3586 -- Component. This routine also applies all appropriate checks to Expr.
3587 -- It finally saves a Expr in the newly created association list that
3588 -- will be attached to the final record aggregate. Note that if the
3589 -- Parent pointer of Expr is not set then Expr was produced with a
3590 -- New_Copy_Tree or some such.
3592 procedure Rewrite_Range (Root_Type : Entity_Id; Rge : Node_Id);
3593 -- Rewrite a range node Rge when its bounds refer to non-stored
3594 -- discriminants from Root_Type, to replace them with the stored
3595 -- discriminant values. This is required in GNATprove mode, and is
3596 -- adopted in all modes to avoid special-casing GNATprove mode.
3598 ---------------------
3599 -- Add_Association --
3600 ---------------------
3602 procedure Add_Association
3603 (Component : Entity_Id;
3605 Assoc_List : List_Id;
3606 Is_Box_Present : Boolean := False)
3608 Choice_List : constant List_Id := New_List;
3612 -- If this is a box association the expression is missing, so use the
3613 -- Sloc of the aggregate itself for the new association.
3615 pragma Assert (Present (Expr) xor Is_Box_Present);
3617 if Present (Expr) then
3623 Append_To (Choice_List, New_Occurrence_Of (Component, Loc));
3625 Append_To (Assoc_List,
3626 Make_Component_Association (Loc,
3627 Choices => Choice_List,
3629 Box_Present => Is_Box_Present));
3630 end Add_Association;
3632 -----------------------------
3633 -- Add_Discriminant_Values --
3634 -----------------------------
3636 procedure Add_Discriminant_Values
3637 (New_Aggr : Node_Id;
3638 Assoc_List : List_Id)
3642 Discr_Elmt : Elmt_Id;
3643 Discr_Val : Node_Id;
3647 Discr := First_Discriminant (Etype (New_Aggr));
3648 Discr_Elmt := First_Elmt (Discriminant_Constraint (Etype (New_Aggr)));
3649 while Present (Discr_Elmt) loop
3650 Discr_Val := Node (Discr_Elmt);
3652 -- If the constraint is given by a discriminant then it is a
3653 -- discriminant of an enclosing record, and its value has already
3654 -- been placed in the association list.
3656 if Is_Entity_Name (Discr_Val)
3657 and then Ekind (Entity (Discr_Val)) = E_Discriminant
3659 Val := Entity (Discr_Val);
3661 Assoc := First (Assoc_List);
3662 while Present (Assoc) loop
3663 if Present (Entity (First (Choices (Assoc))))
3664 and then Entity (First (Choices (Assoc))) = Val
3666 Discr_Val := Expression (Assoc);
3675 (Discr, New_Copy_Tree (Discr_Val),
3676 Component_Associations (New_Aggr));
3678 -- If the discriminant constraint is a current instance, mark the
3679 -- current aggregate so that the self-reference can be expanded
3680 -- later. The constraint may refer to the subtype of aggregate, so
3681 -- use base type for comparison.
3683 if Nkind (Discr_Val) = N_Attribute_Reference
3684 and then Is_Entity_Name (Prefix (Discr_Val))
3685 and then Is_Type (Entity (Prefix (Discr_Val)))
3686 and then Base_Type (Etype (N)) = Entity (Prefix (Discr_Val))
3688 Set_Has_Self_Reference (N);
3691 Next_Elmt (Discr_Elmt);
3692 Next_Discriminant (Discr);
3694 end Add_Discriminant_Values;
3696 --------------------------
3697 -- Discriminant_Present --
3698 --------------------------
3700 function Discriminant_Present (Input_Discr : Entity_Id) return Boolean is
3701 Regular_Aggr : constant Boolean := Nkind (N) /= N_Extension_Aggregate;
3703 Ancestor_Is_Subtyp : Boolean;
3708 Ancestor_Typ : Entity_Id;
3709 Comp_Assoc : Node_Id;
3711 Discr_Expr : Node_Id;
3712 Discr_Val : Elmt_Id := No_Elmt;
3713 Orig_Discr : Entity_Id;
3716 if Regular_Aggr then
3720 -- Check whether inherited discriminant values have already been
3721 -- inserted in the aggregate. This will be the case if we are
3722 -- re-analyzing an aggregate whose expansion was delayed.
3724 if Present (Component_Associations (N)) then
3725 Comp_Assoc := First (Component_Associations (N));
3726 while Present (Comp_Assoc) loop
3727 if Inherited_Discriminant (Comp_Assoc) then
3735 Ancestor := Ancestor_Part (N);
3736 Ancestor_Typ := Etype (Ancestor);
3737 Loc := Sloc (Ancestor);
3739 -- For a private type with unknown discriminants, use the underlying
3740 -- record view if it is available.
3742 if Has_Unknown_Discriminants (Ancestor_Typ)
3743 and then Present (Full_View (Ancestor_Typ))
3744 and then Present (Underlying_Record_View (Full_View (Ancestor_Typ)))
3746 Ancestor_Typ := Underlying_Record_View (Full_View (Ancestor_Typ));
3749 Ancestor_Is_Subtyp :=
3750 Is_Entity_Name (Ancestor) and then Is_Type (Entity (Ancestor));
3752 -- If the ancestor part has no discriminants clearly N's aggregate
3753 -- part must provide a value for Discr.
3755 if not Has_Discriminants (Ancestor_Typ) then
3758 -- If the ancestor part is an unconstrained subtype mark then the
3759 -- Discr must be present in N's aggregate part.
3761 elsif Ancestor_Is_Subtyp
3762 and then not Is_Constrained (Entity (Ancestor))
3767 -- Now look to see if Discr was specified in the ancestor part
3769 if Ancestor_Is_Subtyp then
3771 First_Elmt (Discriminant_Constraint (Entity (Ancestor)));
3774 Orig_Discr := Original_Record_Component (Input_Discr);
3776 Discr := First_Discriminant (Ancestor_Typ);
3777 while Present (Discr) loop
3779 -- If Ancestor has already specified Disc value then insert its
3780 -- value in the final aggregate.
3782 if Original_Record_Component (Discr) = Orig_Discr then
3783 if Ancestor_Is_Subtyp then
3784 Discr_Expr := New_Copy_Tree (Node (Discr_Val));
3787 Make_Selected_Component (Loc,
3788 Prefix => Duplicate_Subexpr (Ancestor),
3789 Selector_Name => New_Occurrence_Of (Input_Discr, Loc));
3792 Resolve_Aggr_Expr (Discr_Expr, Input_Discr);
3793 Set_Inherited_Discriminant (Last (New_Assoc_List));
3797 Next_Discriminant (Discr);
3799 if Ancestor_Is_Subtyp then
3800 Next_Elmt (Discr_Val);
3805 end Discriminant_Present;
3807 ---------------------------
3808 -- Find_Private_Ancestor --
3809 ---------------------------
3811 function Find_Private_Ancestor (Typ : Entity_Id) return Entity_Id is
3817 if Has_Private_Ancestor (Par)
3818 and then not Has_Private_Ancestor (Etype (Base_Type (Par)))
3822 elsif not Is_Derived_Type (Par) then
3826 Par := Etype (Base_Type (Par));
3829 end Find_Private_Ancestor;
3836 (Compon : Entity_Id;
3838 Consider_Others_Choice : Boolean := False) return Node_Id
3840 Typ : constant Entity_Id := Etype (Compon);
3842 Expr : Node_Id := Empty;
3843 Selector_Name : Node_Id;
3846 Is_Box_Present := False;
3852 Assoc := First (From);
3853 while Present (Assoc) loop
3854 Selector_Name := First (Choices (Assoc));
3855 while Present (Selector_Name) loop
3856 if Nkind (Selector_Name) = N_Others_Choice then
3857 if Consider_Others_Choice and then No (Expr) then
3859 -- We need to duplicate the expression for each
3860 -- successive component covered by the others choice.
3861 -- This is redundant if the others_choice covers only
3862 -- one component (small optimization possible???), but
3863 -- indispensable otherwise, because each one must be
3864 -- expanded individually to preserve side effects.
3866 -- Ada 2005 (AI-287): In case of default initialization
3867 -- of components, we duplicate the corresponding default
3868 -- expression (from the record type declaration). The
3869 -- copy must carry the sloc of the association (not the
3870 -- original expression) to prevent spurious elaboration
3871 -- checks when the default includes function calls.
3873 if Box_Present (Assoc) then
3874 Others_Box := Others_Box + 1;
3875 Is_Box_Present := True;
3877 if Expander_Active then
3879 New_Copy_Tree_And_Copy_Dimensions
3880 (Expression (Parent (Compon)),
3881 New_Sloc => Sloc (Assoc));
3883 return Expression (Parent (Compon));
3887 if Present (Others_Etype)
3888 and then Base_Type (Others_Etype) /= Base_Type (Typ)
3890 -- If the components are of an anonymous access
3891 -- type they are distinct, but this is legal in
3892 -- Ada 2012 as long as designated types match.
3894 if (Ekind (Typ) = E_Anonymous_Access_Type
3895 or else Ekind (Typ) =
3896 E_Anonymous_Access_Subprogram_Type)
3897 and then Designated_Type (Typ) =
3898 Designated_Type (Others_Etype)
3903 ("components in OTHERS choice must have same "
3904 & "type", Selector_Name);
3908 Others_Etype := Typ;
3910 -- Copy the expression so that it is resolved
3911 -- independently for each component, This is needed
3912 -- for accessibility checks on compoents of anonymous
3913 -- access types, even in compile_only mode.
3915 if not Inside_A_Generic then
3917 New_Copy_Tree_And_Copy_Dimensions
3918 (Expression (Assoc));
3920 return Expression (Assoc);
3925 elsif Chars (Compon) = Chars (Selector_Name) then
3928 -- Ada 2005 (AI-231)
3930 if Ada_Version >= Ada_2005
3931 and then Known_Null (Expression (Assoc))
3933 Check_Can_Never_Be_Null (Compon, Expression (Assoc));
3936 -- We need to duplicate the expression when several
3937 -- components are grouped together with a "|" choice.
3938 -- For instance "filed1 | filed2 => Expr"
3940 -- Ada 2005 (AI-287)
3942 if Box_Present (Assoc) then
3943 Is_Box_Present := True;
3945 -- Duplicate the default expression of the component
3946 -- from the record type declaration, so a new copy
3947 -- can be attached to the association.
3949 -- Note that we always copy the default expression,
3950 -- even when the association has a single choice, in
3951 -- order to create a proper association for the
3952 -- expanded aggregate.
3954 -- Component may have no default, in which case the
3955 -- expression is empty and the component is default-
3956 -- initialized, but an association for the component
3957 -- exists, and it is not covered by an others clause.
3959 -- Scalar and private types have no initialization
3960 -- procedure, so they remain uninitialized. If the
3961 -- target of the aggregate is a constant this
3962 -- deserves a warning.
3964 if No (Expression (Parent (Compon)))
3965 and then not Has_Non_Null_Base_Init_Proc (Typ)
3966 and then not Has_Aspect (Typ, Aspect_Default_Value)
3967 and then not Is_Concurrent_Type (Typ)
3968 and then Nkind (Parent (N)) = N_Object_Declaration
3969 and then Constant_Present (Parent (N))
3971 Error_Msg_Node_2 := Typ;
3973 ("component&? of type& is uninitialized",
3974 Assoc, Selector_Name);
3976 -- An additional reminder if the component type
3977 -- is a generic formal.
3979 if Is_Generic_Type (Base_Type (Typ)) then
3981 ("\instance should provide actual type with "
3982 & "initialization for&", Assoc, Typ);
3987 New_Copy_Tree_And_Copy_Dimensions
3988 (Expression (Parent (Compon)));
3991 if Present (Next (Selector_Name)) then
3992 Expr := New_Copy_Tree_And_Copy_Dimensions
3993 (Expression (Assoc));
3995 Expr := Expression (Assoc);
3999 Generate_Reference (Compon, Selector_Name, 'm');
4003 ("more than one value supplied for &",
4004 Selector_Name, Compon);
4009 Next (Selector_Name);
4018 -----------------------------
4019 -- Propagate_Discriminants --
4020 -----------------------------
4022 procedure Propagate_Discriminants
4024 Assoc_List : List_Id)
4026 Loc : constant Source_Ptr := Sloc (N);
4028 procedure Process_Component (Comp : Entity_Id);
4029 -- Add one component with a box association to the inner aggregate,
4030 -- and recurse if component is itself composite.
4032 -----------------------
4033 -- Process_Component --
4034 -----------------------
4036 procedure Process_Component (Comp : Entity_Id) is
4037 T : constant Entity_Id := Etype (Comp);
4041 if Is_Record_Type (T) and then Has_Discriminants (T) then
4042 New_Aggr := Make_Aggregate (Loc, No_List, New_List);
4043 Set_Etype (New_Aggr, T);
4046 (Comp, New_Aggr, Component_Associations (Aggr));
4048 -- Collect discriminant values and recurse
4050 Add_Discriminant_Values (New_Aggr, Assoc_List);
4051 Propagate_Discriminants (New_Aggr, Assoc_List);
4053 Build_Constrained_Itype
4054 (New_Aggr, T, Component_Associations (New_Aggr));
4057 (Comp, Empty, Component_Associations (Aggr),
4058 Is_Box_Present => True);
4060 end Process_Component;
4064 Aggr_Type : constant Entity_Id := Base_Type (Etype (Aggr));
4065 Components : constant Elist_Id := New_Elmt_List;
4066 Def_Node : constant Node_Id :=
4067 Type_Definition (Declaration_Node (Aggr_Type));
4070 Comp_Elmt : Elmt_Id;
4073 -- Start of processing for Propagate_Discriminants
4076 -- The component type may be a variant type. Collect the components
4077 -- that are ruled by the known values of the discriminants. Their
4078 -- values have already been inserted into the component list of the
4079 -- current aggregate.
4081 if Nkind (Def_Node) = N_Record_Definition
4082 and then Present (Component_List (Def_Node))
4083 and then Present (Variant_Part (Component_List (Def_Node)))
4085 Gather_Components (Aggr_Type,
4086 Component_List (Def_Node),
4087 Governed_By => Component_Associations (Aggr),
4089 Report_Errors => Errors);
4091 Comp_Elmt := First_Elmt (Components);
4092 while Present (Comp_Elmt) loop
4093 if Ekind (Node (Comp_Elmt)) /= E_Discriminant then
4094 Process_Component (Node (Comp_Elmt));
4097 Next_Elmt (Comp_Elmt);
4100 -- No variant part, iterate over all components
4103 Comp := First_Component (Etype (Aggr));
4104 while Present (Comp) loop
4105 Process_Component (Comp);
4106 Next_Component (Comp);
4109 end Propagate_Discriminants;
4111 -----------------------
4112 -- Resolve_Aggr_Expr --
4113 -----------------------
4115 procedure Resolve_Aggr_Expr (Expr : Node_Id; Component : Entity_Id) is
4116 function Has_Expansion_Delayed (Expr : Node_Id) return Boolean;
4117 -- If the expression is an aggregate (possibly qualified) then its
4118 -- expansion is delayed until the enclosing aggregate is expanded
4119 -- into assignments. In that case, do not generate checks on the
4120 -- expression, because they will be generated later, and will other-
4121 -- wise force a copy (to remove side effects) that would leave a
4122 -- dynamic-sized aggregate in the code, something that gigi cannot
4125 ---------------------------
4126 -- Has_Expansion_Delayed --
4127 ---------------------------
4129 function Has_Expansion_Delayed (Expr : Node_Id) return Boolean is
4132 (Nkind_In (Expr, N_Aggregate, N_Extension_Aggregate)
4133 and then Present (Etype (Expr))
4134 and then Is_Record_Type (Etype (Expr))
4135 and then Expansion_Delayed (Expr))
4137 (Nkind (Expr) = N_Qualified_Expression
4138 and then Has_Expansion_Delayed (Expression (Expr)));
4139 end Has_Expansion_Delayed;
4143 Expr_Type : Entity_Id := Empty;
4144 New_C : Entity_Id := Component;
4148 -- Set to True if the resolved Expr node needs to be relocated when
4149 -- attached to the newly created association list. This node need not
4150 -- be relocated if its parent pointer is not set. In fact in this
4151 -- case Expr is the output of a New_Copy_Tree call. If Relocate is
4152 -- True then we have analyzed the expression node in the original
4153 -- aggregate and hence it needs to be relocated when moved over to
4154 -- the new association list.
4156 -- Start of processing for Resolve_Aggr_Expr
4159 -- If the type of the component is elementary or the type of the
4160 -- aggregate does not contain discriminants, use the type of the
4161 -- component to resolve Expr.
4163 if Is_Elementary_Type (Etype (Component))
4164 or else not Has_Discriminants (Etype (N))
4166 Expr_Type := Etype (Component);
4168 -- Otherwise we have to pick up the new type of the component from
4169 -- the new constrained subtype of the aggregate. In fact components
4170 -- which are of a composite type might be constrained by a
4171 -- discriminant, and we want to resolve Expr against the subtype were
4172 -- all discriminant occurrences are replaced with their actual value.
4175 New_C := First_Component (Etype (N));
4176 while Present (New_C) loop
4177 if Chars (New_C) = Chars (Component) then
4178 Expr_Type := Etype (New_C);
4182 Next_Component (New_C);
4185 pragma Assert (Present (Expr_Type));
4187 -- For each range in an array type where a discriminant has been
4188 -- replaced with the constraint, check that this range is within
4189 -- the range of the base type. This checks is done in the init
4190 -- proc for regular objects, but has to be done here for
4191 -- aggregates since no init proc is called for them.
4193 if Is_Array_Type (Expr_Type) then
4196 -- Range of the current constrained index in the array
4198 Orig_Index : Node_Id := First_Index (Etype (Component));
4199 -- Range corresponding to the range Index above in the
4200 -- original unconstrained record type. The bounds of this
4201 -- range may be governed by discriminants.
4203 Unconstr_Index : Node_Id := First_Index (Etype (Expr_Type));
4204 -- Range corresponding to the range Index above for the
4205 -- unconstrained array type. This range is needed to apply
4209 Index := First_Index (Expr_Type);
4210 while Present (Index) loop
4211 if Depends_On_Discriminant (Orig_Index) then
4212 Apply_Range_Check (Index, Etype (Unconstr_Index));
4216 Next_Index (Orig_Index);
4217 Next_Index (Unconstr_Index);
4223 -- If the Parent pointer of Expr is not set, Expr is an expression
4224 -- duplicated by New_Tree_Copy (this happens for record aggregates
4225 -- that look like (Field1 | Filed2 => Expr) or (others => Expr)).
4226 -- Such a duplicated expression must be attached to the tree
4227 -- before analysis and resolution to enforce the rule that a tree
4228 -- fragment should never be analyzed or resolved unless it is
4229 -- attached to the current compilation unit.
4231 if No (Parent (Expr)) then
4232 Set_Parent (Expr, N);
4238 Analyze_And_Resolve (Expr, Expr_Type);
4239 Check_Expr_OK_In_Limited_Aggregate (Expr);
4240 Check_Non_Static_Context (Expr);
4241 Check_Unset_Reference (Expr);
4243 -- Check wrong use of class-wide types
4245 if Is_Class_Wide_Type (Etype (Expr)) then
4246 Error_Msg_N ("dynamically tagged expression not allowed", Expr);
4249 if not Has_Expansion_Delayed (Expr) then
4250 Aggregate_Constraint_Checks (Expr, Expr_Type);
4253 -- If an aggregate component has a type with predicates, an explicit
4254 -- predicate check must be applied, as for an assignment statement,
4255 -- because the aggregate might not be expanded into individual
4256 -- component assignments.
4258 if Has_Predicates (Expr_Type)
4259 and then Analyzed (Expr)
4261 Apply_Predicate_Check (Expr, Expr_Type);
4264 if Raises_Constraint_Error (Expr) then
4265 Set_Raises_Constraint_Error (N);
4268 -- If the expression has been marked as requiring a range check, then
4269 -- generate it here. It's a bit odd to be generating such checks in
4270 -- the analyzer, but harmless since Generate_Range_Check does nothing
4271 -- (other than making sure Do_Range_Check is set) if the expander is
4274 if Do_Range_Check (Expr) then
4275 Generate_Range_Check (Expr, Expr_Type, CE_Range_Check_Failed);
4278 -- Add association Component => Expr if the caller requests it
4281 New_Expr := Relocate_Node (Expr);
4283 -- Since New_Expr is not gonna be analyzed later on, we need to
4284 -- propagate here the dimensions form Expr to New_Expr.
4286 Copy_Dimensions (Expr, New_Expr);
4292 Add_Association (New_C, New_Expr, New_Assoc_List);
4293 end Resolve_Aggr_Expr;
4299 procedure Rewrite_Range (Root_Type : Entity_Id; Rge : Node_Id) is
4300 procedure Rewrite_Bound
4303 Expr_Disc : Node_Id);
4304 -- Rewrite a bound of the range Bound, when it is equal to the
4305 -- non-stored discriminant Disc, into the stored discriminant
4312 procedure Rewrite_Bound
4315 Expr_Disc : Node_Id)
4318 if Nkind (Bound) /= N_Identifier then
4322 -- We expect either the discriminant or the discriminal
4324 if Entity (Bound) = Disc
4325 or else (Ekind (Entity (Bound)) = E_In_Parameter
4326 and then Discriminal_Link (Entity (Bound)) = Disc)
4328 Rewrite (Bound, New_Copy_Tree (Expr_Disc));
4334 Low, High : Node_Id;
4336 Expr_Disc : Elmt_Id;
4338 -- Start of processing for Rewrite_Range
4341 if Has_Discriminants (Root_Type) and then Nkind (Rge) = N_Range then
4342 Low := Low_Bound (Rge);
4343 High := High_Bound (Rge);
4345 Disc := First_Discriminant (Root_Type);
4346 Expr_Disc := First_Elmt (Stored_Constraint (Etype (N)));
4347 while Present (Disc) loop
4348 Rewrite_Bound (Low, Disc, Node (Expr_Disc));
4349 Rewrite_Bound (High, Disc, Node (Expr_Disc));
4350 Next_Discriminant (Disc);
4351 Next_Elmt (Expr_Disc);
4358 Components : constant Elist_Id := New_Elmt_List;
4359 -- Components is the list of the record components whose value must be
4360 -- provided in the aggregate. This list does include discriminants.
4362 Component : Entity_Id;
4363 Component_Elmt : Elmt_Id;
4365 Positional_Expr : Node_Id;
4367 -- Start of processing for Resolve_Record_Aggregate
4370 -- A record aggregate is restricted in SPARK:
4372 -- Each named association can have only a single choice.
4373 -- OTHERS cannot be used.
4374 -- Positional and named associations cannot be mixed.
4376 if Present (Component_Associations (N))
4377 and then Present (First (Component_Associations (N)))
4383 Assoc := First (Component_Associations (N));
4384 while Present (Assoc) loop
4385 if Nkind (Assoc) = N_Iterated_Component_Association then
4387 ("iterated component association can only appear in an "
4388 & "array aggregate", N);
4389 raise Unrecoverable_Error;
4397 -- We may end up calling Duplicate_Subexpr on expressions that are
4398 -- attached to New_Assoc_List. For this reason we need to attach it
4399 -- to the tree by setting its parent pointer to N. This parent point
4400 -- will change in STEP 8 below.
4402 Set_Parent (New_Assoc_List, N);
4404 -- STEP 1: abstract type and null record verification
4406 if Is_Abstract_Type (Typ) then
4407 Error_Msg_N ("type of aggregate cannot be abstract", N);
4410 if No (First_Entity (Typ)) and then Null_Record_Present (N) then
4414 elsif Present (First_Entity (Typ))
4415 and then Null_Record_Present (N)
4416 and then not Is_Tagged_Type (Typ)
4418 Error_Msg_N ("record aggregate cannot be null", N);
4421 -- If the type has no components, then the aggregate should either
4422 -- have "null record", or in Ada 2005 it could instead have a single
4423 -- component association given by "others => <>". For Ada 95 we flag an
4424 -- error at this point, but for Ada 2005 we proceed with checking the
4425 -- associations below, which will catch the case where it's not an
4426 -- aggregate with "others => <>". Note that the legality of a <>
4427 -- aggregate for a null record type was established by AI05-016.
4429 elsif No (First_Entity (Typ))
4430 and then Ada_Version < Ada_2005
4432 Error_Msg_N ("record aggregate must be null", N);
4436 -- STEP 2: Verify aggregate structure
4440 Bad_Aggregate : Boolean := False;
4441 Selector_Name : Node_Id;
4444 if Present (Component_Associations (N)) then
4445 Assoc := First (Component_Associations (N));
4450 while Present (Assoc) loop
4451 Selector_Name := First (Choices (Assoc));
4452 while Present (Selector_Name) loop
4453 if Nkind (Selector_Name) = N_Identifier then
4456 elsif Nkind (Selector_Name) = N_Others_Choice then
4457 if Selector_Name /= First (Choices (Assoc))
4458 or else Present (Next (Selector_Name))
4461 ("OTHERS must appear alone in a choice list",
4465 elsif Present (Next (Assoc)) then
4467 ("OTHERS must appear last in an aggregate",
4471 -- (Ada 2005): If this is an association with a box,
4472 -- indicate that the association need not represent
4475 elsif Box_Present (Assoc) then
4482 ("selector name should be identifier or OTHERS",
4484 Bad_Aggregate := True;
4487 Next (Selector_Name);
4493 if Bad_Aggregate then
4498 -- STEP 3: Find discriminant Values
4501 Discrim : Entity_Id;
4502 Missing_Discriminants : Boolean := False;
4505 if Present (Expressions (N)) then
4506 Positional_Expr := First (Expressions (N));
4508 Positional_Expr := Empty;
4511 -- AI05-0115: if the ancestor part is a subtype mark, the ancestor
4512 -- must not have unknown discriminants.
4513 -- ??? We are not checking any subtype mark here and this code is not
4514 -- exercised by any test, so it's likely wrong (in particular
4515 -- we should not use Root_Type here but the subtype mark, if any),
4516 -- and possibly not needed.
4518 if Is_Derived_Type (Typ)
4519 and then Has_Unknown_Discriminants (Root_Type (Typ))
4520 and then Nkind (N) /= N_Extension_Aggregate
4523 ("aggregate not available for type& whose ancestor "
4524 & "has unknown discriminants ", N, Typ);
4527 if Has_Unknown_Discriminants (Typ)
4528 and then Present (Underlying_Record_View (Typ))
4530 Discrim := First_Discriminant (Underlying_Record_View (Typ));
4531 elsif Has_Discriminants (Typ) then
4532 Discrim := First_Discriminant (Typ);
4537 -- First find the discriminant values in the positional components
4539 while Present (Discrim) and then Present (Positional_Expr) loop
4540 if Discriminant_Present (Discrim) then
4541 Resolve_Aggr_Expr (Positional_Expr, Discrim);
4543 -- Ada 2005 (AI-231)
4545 if Ada_Version >= Ada_2005
4546 and then Known_Null (Positional_Expr)
4548 Check_Can_Never_Be_Null (Discrim, Positional_Expr);
4551 Next (Positional_Expr);
4554 if Present (Get_Value (Discrim, Component_Associations (N))) then
4556 ("more than one value supplied for discriminant&",
4560 Next_Discriminant (Discrim);
4563 -- Find remaining discriminant values if any among named components
4565 while Present (Discrim) loop
4566 Expr := Get_Value (Discrim, Component_Associations (N), True);
4568 if not Discriminant_Present (Discrim) then
4569 if Present (Expr) then
4571 ("more than one value supplied for discriminant &",
4575 elsif No (Expr) then
4577 ("no value supplied for discriminant &", N, Discrim);
4578 Missing_Discriminants := True;
4581 Resolve_Aggr_Expr (Expr, Discrim);
4584 Next_Discriminant (Discrim);
4587 if Missing_Discriminants then
4591 -- At this point and until the beginning of STEP 6, New_Assoc_List
4592 -- contains only the discriminants and their values.
4596 -- STEP 4: Set the Etype of the record aggregate
4598 if Has_Discriminants (Typ)
4599 or else (Has_Unknown_Discriminants (Typ)
4600 and then Present (Underlying_Record_View (Typ)))
4602 Build_Constrained_Itype (N, Typ, New_Assoc_List);
4607 -- STEP 5: Get remaining components according to discriminant values
4611 Errors_Found : Boolean := False;
4612 Record_Def : Node_Id;
4613 Parent_Typ : Entity_Id;
4614 Parent_Typ_List : Elist_Id;
4615 Parent_Elmt : Elmt_Id;
4616 Root_Typ : Entity_Id;
4619 if Is_Derived_Type (Typ) and then Is_Tagged_Type (Typ) then
4620 Parent_Typ_List := New_Elmt_List;
4622 -- If this is an extension aggregate, the component list must
4623 -- include all components that are not in the given ancestor type.
4624 -- Otherwise, the component list must include components of all
4625 -- ancestors, starting with the root.
4627 if Nkind (N) = N_Extension_Aggregate then
4628 Root_Typ := Base_Type (Etype (Ancestor_Part (N)));
4631 -- AI05-0115: check legality of aggregate for type with a
4632 -- private ancestor.
4634 Root_Typ := Root_Type (Typ);
4635 if Has_Private_Ancestor (Typ) then
4637 Ancestor : constant Entity_Id :=
4638 Find_Private_Ancestor (Typ);
4639 Ancestor_Unit : constant Entity_Id :=
4641 (Get_Source_Unit (Ancestor));
4642 Parent_Unit : constant Entity_Id :=
4643 Cunit_Entity (Get_Source_Unit
4644 (Base_Type (Etype (Ancestor))));
4646 -- Check whether we are in a scope that has full view
4647 -- over the private ancestor and its parent. This can
4648 -- only happen if the derivation takes place in a child
4649 -- unit of the unit that declares the parent, and we are
4650 -- in the private part or body of that child unit, else
4651 -- the aggregate is illegal.
4653 if Is_Child_Unit (Ancestor_Unit)
4654 and then Scope (Ancestor_Unit) = Parent_Unit
4655 and then In_Open_Scopes (Scope (Ancestor))
4657 (In_Private_Part (Scope (Ancestor))
4658 or else In_Package_Body (Scope (Ancestor)))
4664 ("type of aggregate has private ancestor&!",
4666 Error_Msg_N ("must use extension aggregate!", N);
4672 Dnode := Declaration_Node (Base_Type (Root_Typ));
4674 -- If we don't get a full declaration, then we have some error
4675 -- which will get signalled later so skip this part. Otherwise
4676 -- gather components of root that apply to the aggregate type.
4677 -- We use the base type in case there is an applicable stored
4678 -- constraint that renames the discriminants of the root.
4680 if Nkind (Dnode) = N_Full_Type_Declaration then
4681 Record_Def := Type_Definition (Dnode);
4684 Component_List (Record_Def),
4685 Governed_By => New_Assoc_List,
4687 Report_Errors => Errors_Found);
4689 if Errors_Found then
4691 ("discriminant controlling variant part is not static",
4698 Parent_Typ := Base_Type (Typ);
4699 while Parent_Typ /= Root_Typ loop
4700 Prepend_Elmt (Parent_Typ, To => Parent_Typ_List);
4701 Parent_Typ := Etype (Parent_Typ);
4703 if Nkind (Parent (Base_Type (Parent_Typ))) =
4704 N_Private_Type_Declaration
4705 or else Nkind (Parent (Base_Type (Parent_Typ))) =
4706 N_Private_Extension_Declaration
4708 if Nkind (N) /= N_Extension_Aggregate then
4710 ("type of aggregate has private ancestor&!",
4712 Error_Msg_N ("must use extension aggregate!", N);
4715 elsif Parent_Typ /= Root_Typ then
4717 ("ancestor part of aggregate must be private type&",
4718 Ancestor_Part (N), Parent_Typ);
4722 -- The current view of ancestor part may be a private type,
4723 -- while the context type is always non-private.
4725 elsif Is_Private_Type (Root_Typ)
4726 and then Present (Full_View (Root_Typ))
4727 and then Nkind (N) = N_Extension_Aggregate
4729 exit when Base_Type (Full_View (Root_Typ)) = Parent_Typ;
4733 -- Now collect components from all other ancestors, beginning
4734 -- with the current type. If the type has unknown discriminants
4735 -- use the component list of the Underlying_Record_View, which
4736 -- needs to be used for the subsequent expansion of the aggregate
4737 -- into assignments.
4739 Parent_Elmt := First_Elmt (Parent_Typ_List);
4740 while Present (Parent_Elmt) loop
4741 Parent_Typ := Node (Parent_Elmt);
4743 if Has_Unknown_Discriminants (Parent_Typ)
4744 and then Present (Underlying_Record_View (Typ))
4746 Parent_Typ := Underlying_Record_View (Parent_Typ);
4749 Record_Def := Type_Definition (Parent (Base_Type (Parent_Typ)));
4750 Gather_Components (Empty,
4751 Component_List (Record_Extension_Part (Record_Def)),
4752 Governed_By => New_Assoc_List,
4754 Report_Errors => Errors_Found);
4756 Next_Elmt (Parent_Elmt);
4759 -- Typ is not a derived tagged type
4762 Record_Def := Type_Definition (Parent (Base_Type (Typ)));
4764 if Null_Present (Record_Def) then
4767 elsif not Has_Unknown_Discriminants (Typ) then
4770 Component_List (Record_Def),
4771 Governed_By => New_Assoc_List,
4773 Report_Errors => Errors_Found);
4777 (Base_Type (Underlying_Record_View (Typ)),
4778 Component_List (Record_Def),
4779 Governed_By => New_Assoc_List,
4781 Report_Errors => Errors_Found);
4785 if Errors_Found then
4790 -- STEP 6: Find component Values
4793 Component_Elmt := First_Elmt (Components);
4795 -- First scan the remaining positional associations in the aggregate.
4796 -- Remember that at this point Positional_Expr contains the current
4797 -- positional association if any is left after looking for discriminant
4798 -- values in step 3.
4800 while Present (Positional_Expr) and then Present (Component_Elmt) loop
4801 Component := Node (Component_Elmt);
4802 Resolve_Aggr_Expr (Positional_Expr, Component);
4804 -- Ada 2005 (AI-231)
4806 if Ada_Version >= Ada_2005 and then Known_Null (Positional_Expr) then
4807 Check_Can_Never_Be_Null (Component, Positional_Expr);
4810 if Present (Get_Value (Component, Component_Associations (N))) then
4812 ("more than one value supplied for Component &", N, Component);
4815 Next (Positional_Expr);
4816 Next_Elmt (Component_Elmt);
4819 if Present (Positional_Expr) then
4821 ("too many components for record aggregate", Positional_Expr);
4824 -- Now scan for the named arguments of the aggregate
4826 while Present (Component_Elmt) loop
4827 Component := Node (Component_Elmt);
4828 Expr := Get_Value (Component, Component_Associations (N), True);
4830 -- Note: The previous call to Get_Value sets the value of the
4831 -- variable Is_Box_Present.
4833 -- Ada 2005 (AI-287): Handle components with default initialization.
4834 -- Note: This feature was originally added to Ada 2005 for limited
4835 -- but it was finally allowed with any type.
4837 if Is_Box_Present then
4838 Check_Box_Component : declare
4839 Ctyp : constant Entity_Id := Etype (Component);
4842 -- If there is a default expression for the aggregate, copy
4843 -- it into a new association. This copy must modify the scopes
4844 -- of internal types that may be attached to the expression
4845 -- (e.g. index subtypes of arrays) because in general the type
4846 -- declaration and the aggregate appear in different scopes,
4847 -- and the backend requires the scope of the type to match the
4848 -- point at which it is elaborated.
4850 -- If the component has an initialization procedure (IP) we
4851 -- pass the component to the expander, which will generate
4852 -- the call to such IP.
4854 -- If the component has discriminants, their values must
4855 -- be taken from their subtype. This is indispensable for
4856 -- constraints that are given by the current instance of an
4857 -- enclosing type, to allow the expansion of the aggregate to
4858 -- replace the reference to the current instance by the target
4859 -- object of the aggregate.
4861 if Present (Parent (Component))
4862 and then Nkind (Parent (Component)) = N_Component_Declaration
4863 and then Present (Expression (Parent (Component)))
4866 New_Copy_Tree_And_Copy_Dimensions
4867 (Expression (Parent (Component)),
4868 New_Scope => Current_Scope,
4869 New_Sloc => Sloc (N));
4871 -- As the type of the copied default expression may refer
4872 -- to discriminants of the record type declaration, these
4873 -- non-stored discriminants need to be rewritten into stored
4874 -- discriminant values for the aggregate. This is required
4875 -- in GNATprove mode, and is adopted in all modes to avoid
4876 -- special-casing GNATprove mode.
4878 if Is_Array_Type (Etype (Expr)) then
4880 Rec_Typ : constant Entity_Id := Scope (Component);
4881 -- Root record type whose discriminants may be used as
4882 -- bounds in range nodes.
4889 -- Rewrite the range nodes occurring in the indexes
4892 Index := First_Index (Etype (Expr));
4893 while Present (Index) loop
4894 Rewrite_Range (Rec_Typ, Index);
4896 (Rec_Typ, Scalar_Range (Etype (Index)));
4901 -- Rewrite the range nodes occurring as aggregate
4902 -- bounds and component associations.
4904 if Nkind (Expr) = N_Aggregate then
4905 if Present (Aggregate_Bounds (Expr)) then
4906 Rewrite_Range (Rec_Typ, Aggregate_Bounds (Expr));
4909 if Present (Component_Associations (Expr)) then
4910 Assoc := First (Component_Associations (Expr));
4911 while Present (Assoc) loop
4912 Choice := First (Choices (Assoc));
4913 while Present (Choice) loop
4914 Rewrite_Range (Rec_Typ, Choice);
4927 (Component => Component,
4929 Assoc_List => New_Assoc_List);
4930 Set_Has_Self_Reference (N);
4932 -- A box-defaulted access component gets the value null. Also
4933 -- included are components of private types whose underlying
4934 -- type is an access type. In either case set the type of the
4935 -- literal, for subsequent use in semantic checks.
4937 elsif Present (Underlying_Type (Ctyp))
4938 and then Is_Access_Type (Underlying_Type (Ctyp))
4940 -- If the component's type is private with an access type as
4941 -- its underlying type then we have to create an unchecked
4942 -- conversion to satisfy type checking.
4944 if Is_Private_Type (Ctyp) then
4946 Qual_Null : constant Node_Id :=
4947 Make_Qualified_Expression (Sloc (N),
4950 (Underlying_Type (Ctyp), Sloc (N)),
4951 Expression => Make_Null (Sloc (N)));
4953 Convert_Null : constant Node_Id :=
4954 Unchecked_Convert_To
4958 Analyze_And_Resolve (Convert_Null, Ctyp);
4960 (Component => Component,
4961 Expr => Convert_Null,
4962 Assoc_List => New_Assoc_List);
4965 -- Otherwise the component type is non-private
4968 Expr := Make_Null (Sloc (N));
4969 Set_Etype (Expr, Ctyp);
4972 (Component => Component,
4974 Assoc_List => New_Assoc_List);
4977 -- Ada 2012: If component is scalar with default value, use it
4979 elsif Is_Scalar_Type (Ctyp)
4980 and then Has_Default_Aspect (Ctyp)
4983 (Component => Component,
4985 Default_Aspect_Value
4986 (First_Subtype (Underlying_Type (Ctyp))),
4987 Assoc_List => New_Assoc_List);
4989 elsif Has_Non_Null_Base_Init_Proc (Ctyp)
4990 or else not Expander_Active
4992 if Is_Record_Type (Ctyp)
4993 and then Has_Discriminants (Ctyp)
4994 and then not Is_Private_Type (Ctyp)
4996 -- We build a partially initialized aggregate with the
4997 -- values of the discriminants and box initialization
4998 -- for the rest, if other components are present.
5000 -- The type of the aggregate is the known subtype of
5001 -- the component. The capture of discriminants must be
5002 -- recursive because subcomponents may be constrained
5003 -- (transitively) by discriminants of enclosing types.
5004 -- For a private type with discriminants, a call to the
5005 -- initialization procedure will be generated, and no
5006 -- subaggregate is needed.
5008 Capture_Discriminants : declare
5009 Loc : constant Source_Ptr := Sloc (N);
5013 Expr := Make_Aggregate (Loc, No_List, New_List);
5014 Set_Etype (Expr, Ctyp);
5016 -- If the enclosing type has discriminants, they have
5017 -- been collected in the aggregate earlier, and they
5018 -- may appear as constraints of subcomponents.
5020 -- Similarly if this component has discriminants, they
5021 -- might in turn be propagated to their components.
5023 if Has_Discriminants (Typ) then
5024 Add_Discriminant_Values (Expr, New_Assoc_List);
5025 Propagate_Discriminants (Expr, New_Assoc_List);
5027 elsif Has_Discriminants (Ctyp) then
5028 Add_Discriminant_Values
5029 (Expr, Component_Associations (Expr));
5030 Propagate_Discriminants
5031 (Expr, Component_Associations (Expr));
5033 Build_Constrained_Itype
5034 (Expr, Ctyp, Component_Associations (Expr));
5041 -- If the type has additional components, create
5042 -- an OTHERS box association for them.
5044 Comp := First_Component (Ctyp);
5045 while Present (Comp) loop
5046 if Ekind (Comp) = E_Component then
5047 if not Is_Record_Type (Etype (Comp)) then
5049 (Component_Associations (Expr),
5050 Make_Component_Association (Loc,
5053 Make_Others_Choice (Loc)),
5054 Expression => Empty,
5055 Box_Present => True));
5061 Next_Component (Comp);
5067 (Component => Component,
5069 Assoc_List => New_Assoc_List);
5070 end Capture_Discriminants;
5072 -- Otherwise the component type is not a record, or it has
5073 -- not discriminants, or it is private.
5077 (Component => Component,
5079 Assoc_List => New_Assoc_List,
5080 Is_Box_Present => True);
5083 -- Otherwise we only need to resolve the expression if the
5084 -- component has partially initialized values (required to
5085 -- expand the corresponding assignments and run-time checks).
5087 elsif Present (Expr)
5088 and then Is_Partially_Initialized_Type (Ctyp)
5090 Resolve_Aggr_Expr (Expr, Component);
5092 end Check_Box_Component;
5094 elsif No (Expr) then
5096 -- Ignore hidden components associated with the position of the
5097 -- interface tags: these are initialized dynamically.
5099 if not Present (Related_Type (Component)) then
5101 ("no value supplied for component &!", N, Component);
5105 Resolve_Aggr_Expr (Expr, Component);
5108 Next_Elmt (Component_Elmt);
5111 -- STEP 7: check for invalid components + check type in choice list
5115 New_Assoc : Node_Id;
5121 -- Type of first component in choice list
5124 if Present (Component_Associations (N)) then
5125 Assoc := First (Component_Associations (N));
5130 Verification : while Present (Assoc) loop
5131 Selectr := First (Choices (Assoc));
5134 if Nkind (Selectr) = N_Others_Choice then
5136 -- Ada 2005 (AI-287): others choice may have expression or box
5138 if No (Others_Etype) and then Others_Box = 0 then
5140 ("OTHERS must represent at least one component", Selectr);
5142 elsif Others_Box = 1 and then Warn_On_Redundant_Constructs then
5143 Error_Msg_N ("others choice is redundant?", Box_Node);
5145 ("\previous choices cover all components?", Box_Node);
5151 while Present (Selectr) loop
5152 New_Assoc := First (New_Assoc_List);
5153 while Present (New_Assoc) loop
5154 Component := First (Choices (New_Assoc));
5156 if Chars (Selectr) = Chars (Component) then
5158 Check_Identifier (Selectr, Entity (Component));
5167 -- If no association, this is not a legal component of the type
5168 -- in question, unless its association is provided with a box.
5170 if No (New_Assoc) then
5171 if Box_Present (Parent (Selectr)) then
5173 -- This may still be a bogus component with a box. Scan
5174 -- list of components to verify that a component with
5175 -- that name exists.
5181 C := First_Component (Typ);
5182 while Present (C) loop
5183 if Chars (C) = Chars (Selectr) then
5185 -- If the context is an extension aggregate,
5186 -- the component must not be inherited from
5187 -- the ancestor part of the aggregate.
5189 if Nkind (N) /= N_Extension_Aggregate
5191 Scope (Original_Record_Component (C)) /=
5192 Etype (Ancestor_Part (N))
5202 Error_Msg_Node_2 := Typ;
5203 Error_Msg_N ("& is not a component of}", Selectr);
5207 elsif Chars (Selectr) /= Name_uTag
5208 and then Chars (Selectr) /= Name_uParent
5210 if not Has_Discriminants (Typ) then
5211 Error_Msg_Node_2 := Typ;
5212 Error_Msg_N ("& is not a component of}", Selectr);
5215 ("& is not a component of the aggregate subtype",
5219 Check_Misspelled_Component (Components, Selectr);
5222 elsif No (Typech) then
5223 Typech := Base_Type (Etype (Component));
5225 -- AI05-0199: In Ada 2012, several components of anonymous
5226 -- access types can appear in a choice list, as long as the
5227 -- designated types match.
5229 elsif Typech /= Base_Type (Etype (Component)) then
5230 if Ada_Version >= Ada_2012
5231 and then Ekind (Typech) = E_Anonymous_Access_Type
5233 Ekind (Etype (Component)) = E_Anonymous_Access_Type
5234 and then Base_Type (Designated_Type (Typech)) =
5235 Base_Type (Designated_Type (Etype (Component)))
5237 Subtypes_Statically_Match (Typech, (Etype (Component)))
5241 elsif not Box_Present (Parent (Selectr)) then
5243 ("components in choice list must have same type",
5252 end loop Verification;
5255 -- STEP 8: replace the original aggregate
5258 New_Aggregate : constant Node_Id := New_Copy (N);
5261 Set_Expressions (New_Aggregate, No_List);
5262 Set_Etype (New_Aggregate, Etype (N));
5263 Set_Component_Associations (New_Aggregate, New_Assoc_List);
5264 Set_Check_Actuals (New_Aggregate, Check_Actuals (N));
5266 Rewrite (N, New_Aggregate);
5269 -- Check the dimensions of the components in the record aggregate
5271 Analyze_Dimension_Extension_Or_Record_Aggregate (N);
5272 end Resolve_Record_Aggregate;
5274 -----------------------------
5275 -- Check_Can_Never_Be_Null --
5276 -----------------------------
5278 procedure Check_Can_Never_Be_Null (Typ : Entity_Id; Expr : Node_Id) is
5279 Comp_Typ : Entity_Id;
5283 (Ada_Version >= Ada_2005
5284 and then Present (Expr)
5285 and then Known_Null (Expr));
5288 when E_Array_Type =>
5289 Comp_Typ := Component_Type (Typ);
5294 Comp_Typ := Etype (Typ);
5300 if Can_Never_Be_Null (Comp_Typ) then
5302 -- Here we know we have a constraint error. Note that we do not use
5303 -- Apply_Compile_Time_Constraint_Error here to the Expr, which might
5304 -- seem the more natural approach. That's because in some cases the
5305 -- components are rewritten, and the replacement would be missed.
5306 -- We do not mark the whole aggregate as raising a constraint error,
5307 -- because the association may be a null array range.
5310 ("(Ada 2005) null not allowed in null-excluding component??", Expr);
5312 ("\Constraint_Error will be raised at run time??", Expr);
5315 Make_Raise_Constraint_Error
5316 (Sloc (Expr), Reason => CE_Access_Check_Failed));
5317 Set_Etype (Expr, Comp_Typ);
5318 Set_Analyzed (Expr);
5320 end Check_Can_Never_Be_Null;
5322 ---------------------
5323 -- Sort_Case_Table --
5324 ---------------------
5326 procedure Sort_Case_Table (Case_Table : in out Case_Table_Type) is
5327 U : constant Int := Case_Table'Last;
5335 T := Case_Table (K + 1);
5339 and then Expr_Value (Case_Table (J - 1).Lo) > Expr_Value (T.Lo)
5341 Case_Table (J) := Case_Table (J - 1);
5345 Case_Table (J) := T;
5348 end Sort_Case_Table;