1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2006, 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 2, 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 COPYING. If not, write --
19 -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
20 -- Boston, MA 02110-1301, USA. --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
25 ------------------------------------------------------------------------------
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Errout; use Errout;
32 with Exp_Tss; use Exp_Tss;
33 with Exp_Util; use Exp_Util;
34 with Freeze; use Freeze;
35 with Itypes; use Itypes;
36 with Lib.Xref; use Lib.Xref;
37 with Namet; use Namet;
38 with Nmake; use Nmake;
39 with Nlists; use Nlists;
42 with Sem_Cat; use Sem_Cat;
43 with Sem_Ch3; use Sem_Ch3;
44 with Sem_Ch8; use Sem_Ch8;
45 with Sem_Ch13; use Sem_Ch13;
46 with Sem_Eval; use Sem_Eval;
47 with Sem_Res; use Sem_Res;
48 with Sem_Util; use Sem_Util;
49 with Sem_Type; use Sem_Type;
50 with Sem_Warn; use Sem_Warn;
51 with Sinfo; use Sinfo;
52 with Snames; use Snames;
53 with Stringt; use Stringt;
54 with Stand; use Stand;
55 with Targparm; use Targparm;
56 with Tbuild; use Tbuild;
57 with Uintp; use Uintp;
59 with GNAT.Spelling_Checker; use GNAT.Spelling_Checker;
61 package body Sem_Aggr is
63 type Case_Bounds is record
66 Choice_Node : Node_Id;
69 type Case_Table_Type is array (Nat range <>) of Case_Bounds;
70 -- Table type used by Check_Case_Choices procedure
72 -----------------------
73 -- Local Subprograms --
74 -----------------------
76 procedure Sort_Case_Table (Case_Table : in out Case_Table_Type);
77 -- Sort the Case Table using the Lower Bound of each Choice as the key.
78 -- A simple insertion sort is used since the number of choices in a case
79 -- statement of variant part will usually be small and probably in near
82 procedure Check_Can_Never_Be_Null (Typ : Entity_Id; Expr : Node_Id);
83 -- Ada 2005 (AI-231): Check bad usage of null for a component for which
84 -- null exclusion (NOT NULL) is specified. Typ can be an E_Array_Type for
85 -- the array case (the component type of the array will be used) or an
86 -- E_Component/E_Discriminant entity in the record case, in which case the
87 -- type of the component will be used for the test. If Typ is any other
88 -- kind of entity, the call is ignored. Expr is the component node in the
89 -- aggregate which is an explicit occurrence of NULL. An error will be
90 -- issued if the component is null excluding.
92 -- It would be better to pass the proper type for Typ ???
94 ------------------------------------------------------
95 -- Subprograms used for RECORD AGGREGATE Processing --
96 ------------------------------------------------------
98 procedure Resolve_Record_Aggregate (N : Node_Id; Typ : Entity_Id);
99 -- This procedure performs all the semantic checks required for record
100 -- aggregates. Note that for aggregates analysis and resolution go
101 -- hand in hand. Aggregate analysis has been delayed up to here and
102 -- it is done while resolving the aggregate.
104 -- N is the N_Aggregate node.
105 -- Typ is the record type for the aggregate resolution
107 -- While performing the semantic checks, this procedure builds a new
108 -- Component_Association_List where each record field appears alone in a
109 -- Component_Choice_List along with its corresponding expression. The
110 -- record fields in the Component_Association_List appear in the same order
111 -- in which they appear in the record type Typ.
113 -- Once this new Component_Association_List is built and all the semantic
114 -- checks performed, the original aggregate subtree is replaced with the
115 -- new named record aggregate just built. Note that subtree substitution is
116 -- performed with Rewrite so as to be able to retrieve the original
119 -- The aggregate subtree manipulation performed by Resolve_Record_Aggregate
120 -- yields the aggregate format expected by Gigi. Typically, this kind of
121 -- tree manipulations are done in the expander. However, because the
122 -- semantic checks that need to be performed on record aggregates really go
123 -- hand in hand with the record aggregate normalization, the aggregate
124 -- subtree transformation is performed during resolution rather than
125 -- expansion. Had we decided otherwise we would have had to duplicate most
126 -- of the code in the expansion procedure Expand_Record_Aggregate. Note,
127 -- however, that all the expansion concerning aggegates for tagged records
128 -- is done in Expand_Record_Aggregate.
130 -- The algorithm of Resolve_Record_Aggregate proceeds as follows:
132 -- 1. Make sure that the record type against which the record aggregate
133 -- has to be resolved is not abstract. Furthermore if the type is
134 -- a null aggregate make sure the input aggregate N is also null.
136 -- 2. Verify that the structure of the aggregate is that of a record
137 -- aggregate. Specifically, look for component associations and ensure
138 -- that each choice list only has identifiers or the N_Others_Choice
139 -- node. Also make sure that if present, the N_Others_Choice occurs
140 -- last and by itself.
142 -- 3. If Typ contains discriminants, the values for each discriminant
143 -- is looked for. If the record type Typ has variants, we check
144 -- that the expressions corresponding to each discriminant ruling
145 -- the (possibly nested) variant parts of Typ, are static. This
146 -- allows us to determine the variant parts to which the rest of
147 -- the aggregate must conform. The names of discriminants with their
148 -- values are saved in a new association list, New_Assoc_List which
149 -- is later augmented with the names and values of the remaining
150 -- components in the record type.
152 -- During this phase we also make sure that every discriminant is
153 -- assigned exactly one value. Note that when several values
154 -- for a given discriminant are found, semantic processing continues
155 -- looking for further errors. In this case it's the first
156 -- discriminant value found which we will be recorded.
158 -- IMPORTANT NOTE: For derived tagged types this procedure expects
159 -- First_Discriminant and Next_Discriminant to give the correct list
160 -- of discriminants, in the correct order.
162 -- 4. After all the discriminant values have been gathered, we can
163 -- set the Etype of the record aggregate. If Typ contains no
164 -- discriminants this is straightforward: the Etype of N is just
165 -- Typ, otherwise a new implicit constrained subtype of Typ is
166 -- built to be the Etype of N.
168 -- 5. Gather the remaining record components according to the discriminant
169 -- values. This involves recursively traversing the record type
170 -- structure to see what variants are selected by the given discriminant
171 -- values. This processing is a little more convoluted if Typ is a
172 -- derived tagged types since we need to retrieve the record structure
173 -- of all the ancestors of Typ.
175 -- 6. After gathering the record components we look for their values
176 -- in the record aggregate and emit appropriate error messages
177 -- should we not find such values or should they be duplicated.
179 -- 7. We then make sure no illegal component names appear in the
180 -- record aggegate and make sure that the type of the record
181 -- components appearing in a same choice list is the same.
182 -- Finally we ensure that the others choice, if present, is
183 -- used to provide the value of at least a record component.
185 -- 8. The original aggregate node is replaced with the new named
186 -- aggregate built in steps 3 through 6, as explained earlier.
188 -- Given the complexity of record aggregate resolution, the primary
189 -- goal of this routine is clarity and simplicity rather than execution
190 -- and storage efficiency. If there are only positional components in the
191 -- aggregate the running time is linear. If there are associations
192 -- the running time is still linear as long as the order of the
193 -- associations is not too far off the order of the components in the
194 -- record type. If this is not the case the running time is at worst
195 -- quadratic in the size of the association list.
197 procedure Check_Misspelled_Component
198 (Elements : Elist_Id;
199 Component : Node_Id);
200 -- Give possible misspelling diagnostic if Component is likely to be
201 -- a misspelling of one of the components of the Assoc_List.
202 -- This is called by Resolv_Aggr_Expr after producing
203 -- an invalid component error message.
205 procedure Check_Static_Discriminated_Subtype (T : Entity_Id; V : Node_Id);
206 -- An optimization: determine whether a discriminated subtype has a
207 -- static constraint, and contains array components whose length is also
208 -- static, either because they are constrained by the discriminant, or
209 -- because the original component bounds are static.
211 -----------------------------------------------------
212 -- Subprograms used for ARRAY AGGREGATE Processing --
213 -----------------------------------------------------
215 function Resolve_Array_Aggregate
218 Index_Constr : Node_Id;
219 Component_Typ : Entity_Id;
220 Others_Allowed : Boolean)
222 -- This procedure performs the semantic checks for an array aggregate.
223 -- True is returned if the aggregate resolution succeeds.
224 -- The procedure works by recursively checking each nested aggregate.
225 -- Specifically, after checking a sub-aggregate nested at the i-th level
226 -- we recursively check all the subaggregates at the i+1-st level (if any).
227 -- Note that for aggregates analysis and resolution go hand in hand.
228 -- Aggregate analysis has been delayed up to here and it is done while
229 -- resolving the aggregate.
231 -- N is the current N_Aggregate node to be checked.
233 -- Index is the index node corresponding to the array sub-aggregate that
234 -- we are currently checking (RM 4.3.3 (8)). Its Etype is the
235 -- corresponding index type (or subtype).
237 -- Index_Constr is the node giving the applicable index constraint if
238 -- any (RM 4.3.3 (10)). It "is a constraint provided by certain
239 -- contexts [...] that can be used to determine the bounds of the array
240 -- value specified by the aggregate". If Others_Allowed below is False
241 -- there is no applicable index constraint and this node is set to Index.
243 -- Component_Typ is the array component type.
245 -- Others_Allowed indicates whether an others choice is allowed
246 -- in the context where the top-level aggregate appeared.
248 -- The algorithm of Resolve_Array_Aggregate proceeds as follows:
250 -- 1. Make sure that the others choice, if present, is by itself and
251 -- appears last in the sub-aggregate. Check that we do not have
252 -- positional and named components in the array sub-aggregate (unless
253 -- the named association is an others choice). Finally if an others
254 -- choice is present, make sure it is allowed in the aggregate contex.
256 -- 2. If the array sub-aggregate contains discrete_choices:
258 -- (A) Verify their validity. Specifically verify that:
260 -- (a) If a null range is present it must be the only possible
261 -- choice in the array aggregate.
263 -- (b) Ditto for a non static range.
265 -- (c) Ditto for a non static expression.
267 -- In addition this step analyzes and resolves each discrete_choice,
268 -- making sure that its type is the type of the corresponding Index.
269 -- If we are not at the lowest array aggregate level (in the case of
270 -- multi-dimensional aggregates) then invoke Resolve_Array_Aggregate
271 -- recursively on each component expression. Otherwise, resolve the
272 -- bottom level component expressions against the expected component
273 -- type ONLY IF the component corresponds to a single discrete choice
274 -- which is not an others choice (to see why read the DELAYED
275 -- COMPONENT RESOLUTION below).
277 -- (B) Determine the bounds of the sub-aggregate and lowest and
278 -- highest choice values.
280 -- 3. For positional aggregates:
282 -- (A) Loop over the component expressions either recursively invoking
283 -- Resolve_Array_Aggregate on each of these for multi-dimensional
284 -- array aggregates or resolving the bottom level component
285 -- expressions against the expected component type.
287 -- (B) Determine the bounds of the positional sub-aggregates.
289 -- 4. Try to determine statically whether the evaluation of the array
290 -- sub-aggregate raises Constraint_Error. If yes emit proper
291 -- warnings. The precise checks are the following:
293 -- (A) Check that the index range defined by aggregate bounds is
294 -- compatible with corresponding index subtype.
295 -- We also check against the base type. In fact it could be that
296 -- Low/High bounds of the base type are static whereas those of
297 -- the index subtype are not. Thus if we can statically catch
298 -- a problem with respect to the base type we are guaranteed
299 -- that the same problem will arise with the index subtype
301 -- (B) If we are dealing with a named aggregate containing an others
302 -- choice and at least one discrete choice then make sure the range
303 -- specified by the discrete choices does not overflow the
304 -- aggregate bounds. We also check against the index type and base
305 -- type bounds for the same reasons given in (A).
307 -- (C) If we are dealing with a positional aggregate with an others
308 -- choice make sure the number of positional elements specified
309 -- does not overflow the aggregate bounds. We also check against
310 -- the index type and base type bounds as mentioned in (A).
312 -- Finally construct an N_Range node giving the sub-aggregate bounds.
313 -- Set the Aggregate_Bounds field of the sub-aggregate to be this
314 -- N_Range. The routine Array_Aggr_Subtype below uses such N_Ranges
315 -- to build the appropriate aggregate subtype. Aggregate_Bounds
316 -- information is needed during expansion.
318 -- DELAYED COMPONENT RESOLUTION: The resolution of bottom level component
319 -- expressions in an array aggregate may call Duplicate_Subexpr or some
320 -- other routine that inserts code just outside the outermost aggregate.
321 -- If the array aggregate contains discrete choices or an others choice,
322 -- this may be wrong. Consider for instance the following example.
324 -- type Rec is record
328 -- type Acc_Rec is access Rec;
329 -- Arr : array (1..3) of Acc_Rec := (1 .. 3 => new Rec);
331 -- Then the transformation of "new Rec" that occurs during resolution
332 -- entails the following code modifications
334 -- P7b : constant Acc_Rec := new Rec;
336 -- Arr : array (1..3) of Acc_Rec := (1 .. 3 => P7b);
338 -- This code transformation is clearly wrong, since we need to call
339 -- "new Rec" for each of the 3 array elements. To avoid this problem we
340 -- delay resolution of the components of non positional array aggregates
341 -- to the expansion phase. As an optimization, if the discrete choice
342 -- specifies a single value we do not delay resolution.
344 function Array_Aggr_Subtype (N : Node_Id; Typ : Node_Id) return Entity_Id;
345 -- This routine returns the type or subtype of an array aggregate.
347 -- N is the array aggregate node whose type we return.
349 -- Typ is the context type in which N occurs.
351 -- This routine creates an implicit array subtype whose bounds are
352 -- those defined by the aggregate. When this routine is invoked
353 -- Resolve_Array_Aggregate has already processed aggregate N. Thus the
354 -- Aggregate_Bounds of each sub-aggregate, is an N_Range node giving the
355 -- sub-aggregate bounds. When building the aggegate itype, this function
356 -- traverses the array aggregate N collecting such Aggregate_Bounds and
357 -- constructs the proper array aggregate itype.
359 -- Note that in the case of multidimensional aggregates each inner
360 -- sub-aggregate corresponding to a given array dimension, may provide a
361 -- different bounds. If it is possible to determine statically that
362 -- some sub-aggregates corresponding to the same index do not have the
363 -- same bounds, then a warning is emitted. If such check is not possible
364 -- statically (because some sub-aggregate bounds are dynamic expressions)
365 -- then this job is left to the expander. In all cases the particular
366 -- bounds that this function will chose for a given dimension is the first
367 -- N_Range node for a sub-aggregate corresponding to that dimension.
369 -- Note that the Raises_Constraint_Error flag of an array aggregate
370 -- whose evaluation is determined to raise CE by Resolve_Array_Aggregate,
371 -- is set in Resolve_Array_Aggregate but the aggregate is not
372 -- immediately replaced with a raise CE. In fact, Array_Aggr_Subtype must
373 -- first construct the proper itype for the aggregate (Gigi needs
374 -- this). After constructing the proper itype we will eventually replace
375 -- the top-level aggregate with a raise CE (done in Resolve_Aggregate).
376 -- Of course in cases such as:
378 -- type Arr is array (integer range <>) of Integer;
379 -- A : Arr := (positive range -1 .. 2 => 0);
381 -- The bounds of the aggregate itype are cooked up to look reasonable
382 -- (in this particular case the bounds will be 1 .. 2).
384 procedure Aggregate_Constraint_Checks
386 Check_Typ : Entity_Id);
387 -- Checks expression Exp against subtype Check_Typ. If Exp is an
388 -- aggregate and Check_Typ a constrained record type with discriminants,
389 -- we generate the appropriate discriminant checks. If Exp is an array
390 -- aggregate then emit the appropriate length checks. If Exp is a scalar
391 -- type, or a string literal, Exp is changed into Check_Typ'(Exp) to
392 -- ensure that range checks are performed at run time.
394 procedure Make_String_Into_Aggregate (N : Node_Id);
395 -- A string literal can appear in a context in which a one dimensional
396 -- array of characters is expected. This procedure simply rewrites the
397 -- string as an aggregate, prior to resolution.
399 ---------------------------------
400 -- Aggregate_Constraint_Checks --
401 ---------------------------------
403 procedure Aggregate_Constraint_Checks
405 Check_Typ : Entity_Id)
407 Exp_Typ : constant Entity_Id := Etype (Exp);
410 if Raises_Constraint_Error (Exp) then
414 -- This is really expansion activity, so make sure that expansion
415 -- is on and is allowed.
417 if not Expander_Active or else In_Default_Expression then
421 -- First check if we have to insert discriminant checks
423 if Has_Discriminants (Exp_Typ) then
424 Apply_Discriminant_Check (Exp, Check_Typ);
426 -- Next emit length checks for array aggregates
428 elsif Is_Array_Type (Exp_Typ) then
429 Apply_Length_Check (Exp, Check_Typ);
431 -- Finally emit scalar and string checks. If we are dealing with a
432 -- scalar literal we need to check by hand because the Etype of
433 -- literals is not necessarily correct.
435 elsif Is_Scalar_Type (Exp_Typ)
436 and then Compile_Time_Known_Value (Exp)
438 if Is_Out_Of_Range (Exp, Base_Type (Check_Typ)) then
439 Apply_Compile_Time_Constraint_Error
440 (Exp, "value not in range of}?", CE_Range_Check_Failed,
441 Ent => Base_Type (Check_Typ),
442 Typ => Base_Type (Check_Typ));
444 elsif Is_Out_Of_Range (Exp, Check_Typ) then
445 Apply_Compile_Time_Constraint_Error
446 (Exp, "value not in range of}?", CE_Range_Check_Failed,
450 elsif not Range_Checks_Suppressed (Check_Typ) then
451 Apply_Scalar_Range_Check (Exp, Check_Typ);
454 -- Verify that target type is also scalar, to prevent view anomalies
455 -- in instantiations.
457 elsif (Is_Scalar_Type (Exp_Typ)
458 or else Nkind (Exp) = N_String_Literal)
459 and then Is_Scalar_Type (Check_Typ)
460 and then Exp_Typ /= Check_Typ
462 if Is_Entity_Name (Exp)
463 and then Ekind (Entity (Exp)) = E_Constant
465 -- If expression is a constant, it is worthwhile checking whether
466 -- it is a bound of the type.
468 if (Is_Entity_Name (Type_Low_Bound (Check_Typ))
469 and then Entity (Exp) = Entity (Type_Low_Bound (Check_Typ)))
470 or else (Is_Entity_Name (Type_High_Bound (Check_Typ))
471 and then Entity (Exp) = Entity (Type_High_Bound (Check_Typ)))
476 Rewrite (Exp, Convert_To (Check_Typ, Relocate_Node (Exp)));
477 Analyze_And_Resolve (Exp, Check_Typ);
478 Check_Unset_Reference (Exp);
481 Rewrite (Exp, Convert_To (Check_Typ, Relocate_Node (Exp)));
482 Analyze_And_Resolve (Exp, Check_Typ);
483 Check_Unset_Reference (Exp);
486 -- Ada 2005 (AI-230): Generate a conversion to an anonymous access
487 -- component's type to force the appropriate accessibility checks.
489 -- Ada 2005 (AI-231): Generate conversion to the null-excluding
490 -- type to force the corresponding run-time check
492 elsif Is_Access_Type (Check_Typ)
493 and then ((Is_Local_Anonymous_Access (Check_Typ))
494 or else (Can_Never_Be_Null (Check_Typ)
495 and then not Can_Never_Be_Null (Exp_Typ)))
497 Rewrite (Exp, Convert_To (Check_Typ, Relocate_Node (Exp)));
498 Analyze_And_Resolve (Exp, Check_Typ);
499 Check_Unset_Reference (Exp);
501 end Aggregate_Constraint_Checks;
503 ------------------------
504 -- Array_Aggr_Subtype --
505 ------------------------
507 function Array_Aggr_Subtype
512 Aggr_Dimension : constant Pos := Number_Dimensions (Typ);
513 -- Number of aggregate index dimensions
515 Aggr_Range : array (1 .. Aggr_Dimension) of Node_Id := (others => Empty);
516 -- Constrained N_Range of each index dimension in our aggregate itype
518 Aggr_Low : array (1 .. Aggr_Dimension) of Node_Id := (others => Empty);
519 Aggr_High : array (1 .. Aggr_Dimension) of Node_Id := (others => Empty);
520 -- Low and High bounds for each index dimension in our aggregate itype
522 Is_Fully_Positional : Boolean := True;
524 procedure Collect_Aggr_Bounds (N : Node_Id; Dim : Pos);
525 -- N is an array (sub-)aggregate. Dim is the dimension corresponding to
526 -- (sub-)aggregate N. This procedure collects the constrained N_Range
527 -- nodes corresponding to each index dimension of our aggregate itype.
528 -- These N_Range nodes are collected in Aggr_Range above.
530 -- Likewise collect in Aggr_Low & Aggr_High above the low and high
531 -- bounds of each index dimension. If, when collecting, two bounds
532 -- corresponding to the same dimension are static and found to differ,
533 -- then emit a warning, and mark N as raising Constraint_Error.
535 -------------------------
536 -- Collect_Aggr_Bounds --
537 -------------------------
539 procedure Collect_Aggr_Bounds (N : Node_Id; Dim : Pos) is
540 This_Range : constant Node_Id := Aggregate_Bounds (N);
541 -- The aggregate range node of this specific sub-aggregate
543 This_Low : constant Node_Id := Low_Bound (Aggregate_Bounds (N));
544 This_High : constant Node_Id := High_Bound (Aggregate_Bounds (N));
545 -- The aggregate bounds of this specific sub-aggregate
551 -- Collect the first N_Range for a given dimension that you find.
552 -- For a given dimension they must be all equal anyway.
554 if No (Aggr_Range (Dim)) then
555 Aggr_Low (Dim) := This_Low;
556 Aggr_High (Dim) := This_High;
557 Aggr_Range (Dim) := This_Range;
560 if Compile_Time_Known_Value (This_Low) then
561 if not Compile_Time_Known_Value (Aggr_Low (Dim)) then
562 Aggr_Low (Dim) := This_Low;
564 elsif Expr_Value (This_Low) /= Expr_Value (Aggr_Low (Dim)) then
565 Set_Raises_Constraint_Error (N);
566 Error_Msg_N ("sub-aggregate low bound mismatch?", N);
568 ("\Constraint_Error will be raised at run-time?", N);
572 if Compile_Time_Known_Value (This_High) then
573 if not Compile_Time_Known_Value (Aggr_High (Dim)) then
574 Aggr_High (Dim) := This_High;
577 Expr_Value (This_High) /= Expr_Value (Aggr_High (Dim))
579 Set_Raises_Constraint_Error (N);
580 Error_Msg_N ("sub-aggregate high bound mismatch?", N);
582 ("\Constraint_Error will be raised at run-time?", N);
587 if Dim < Aggr_Dimension then
589 -- Process positional components
591 if Present (Expressions (N)) then
592 Expr := First (Expressions (N));
593 while Present (Expr) loop
594 Collect_Aggr_Bounds (Expr, Dim + 1);
599 -- Process component associations
601 if Present (Component_Associations (N)) then
602 Is_Fully_Positional := False;
604 Assoc := First (Component_Associations (N));
605 while Present (Assoc) loop
606 Expr := Expression (Assoc);
607 Collect_Aggr_Bounds (Expr, Dim + 1);
612 end Collect_Aggr_Bounds;
614 -- Array_Aggr_Subtype variables
617 -- the final itype of the overall aggregate
619 Index_Constraints : constant List_Id := New_List;
620 -- The list of index constraints of the aggregate itype
622 -- Start of processing for Array_Aggr_Subtype
625 -- Make sure that the list of index constraints is properly attached
626 -- to the tree, and then collect the aggregate bounds.
628 Set_Parent (Index_Constraints, N);
629 Collect_Aggr_Bounds (N, 1);
631 -- Build the list of constrained indices of our aggregate itype
633 for J in 1 .. Aggr_Dimension loop
634 Create_Index : declare
635 Index_Base : constant Entity_Id :=
636 Base_Type (Etype (Aggr_Range (J)));
637 Index_Typ : Entity_Id;
640 -- Construct the Index subtype
642 Index_Typ := Create_Itype (Subtype_Kind (Ekind (Index_Base)), N);
644 Set_Etype (Index_Typ, Index_Base);
646 if Is_Character_Type (Index_Base) then
647 Set_Is_Character_Type (Index_Typ);
650 Set_Size_Info (Index_Typ, (Index_Base));
651 Set_RM_Size (Index_Typ, RM_Size (Index_Base));
652 Set_First_Rep_Item (Index_Typ, First_Rep_Item (Index_Base));
653 Set_Scalar_Range (Index_Typ, Aggr_Range (J));
655 if Is_Discrete_Or_Fixed_Point_Type (Index_Typ) then
656 Set_RM_Size (Index_Typ, UI_From_Int (Minimum_Size (Index_Typ)));
659 Set_Etype (Aggr_Range (J), Index_Typ);
661 Append (Aggr_Range (J), To => Index_Constraints);
665 -- Now build the Itype
667 Itype := Create_Itype (E_Array_Subtype, N);
669 Set_First_Rep_Item (Itype, First_Rep_Item (Typ));
670 Set_Convention (Itype, Convention (Typ));
671 Set_Depends_On_Private (Itype, Has_Private_Component (Typ));
672 Set_Etype (Itype, Base_Type (Typ));
673 Set_Has_Alignment_Clause (Itype, Has_Alignment_Clause (Typ));
674 Set_Is_Aliased (Itype, Is_Aliased (Typ));
675 Set_Depends_On_Private (Itype, Depends_On_Private (Typ));
677 Copy_Suppress_Status (Index_Check, Typ, Itype);
678 Copy_Suppress_Status (Length_Check, Typ, Itype);
680 Set_First_Index (Itype, First (Index_Constraints));
681 Set_Is_Constrained (Itype, True);
682 Set_Is_Internal (Itype, True);
683 Init_Size_Align (Itype);
685 -- A simple optimization: purely positional aggregates of static
686 -- components should be passed to gigi unexpanded whenever possible,
687 -- and regardless of the staticness of the bounds themselves. Subse-
688 -- quent checks in exp_aggr verify that type is not packed, etc.
690 Set_Size_Known_At_Compile_Time (Itype,
692 and then Comes_From_Source (N)
693 and then Size_Known_At_Compile_Time (Component_Type (Typ)));
695 -- We always need a freeze node for a packed array subtype, so that
696 -- we can build the Packed_Array_Type corresponding to the subtype.
697 -- If expansion is disabled, the packed array subtype is not built,
698 -- and we must not generate a freeze node for the type, or else it
699 -- will appear incomplete to gigi.
701 if Is_Packed (Itype) and then not In_Default_Expression
702 and then Expander_Active
704 Freeze_Itype (Itype, N);
708 end Array_Aggr_Subtype;
710 --------------------------------
711 -- Check_Misspelled_Component --
712 --------------------------------
714 procedure Check_Misspelled_Component
715 (Elements : Elist_Id;
718 Max_Suggestions : constant := 2;
720 Nr_Of_Suggestions : Natural := 0;
721 Suggestion_1 : Entity_Id := Empty;
722 Suggestion_2 : Entity_Id := Empty;
723 Component_Elmt : Elmt_Id;
726 -- All the components of List are matched against Component and
727 -- a count is maintained of possible misspellings. When at the
728 -- end of the analysis there are one or two (not more!) possible
729 -- misspellings, these misspellings will be suggested as
730 -- possible correction.
732 Get_Name_String (Chars (Component));
735 S : constant String (1 .. Name_Len) :=
736 Name_Buffer (1 .. Name_Len);
739 Component_Elmt := First_Elmt (Elements);
740 while Nr_Of_Suggestions <= Max_Suggestions
741 and then Present (Component_Elmt)
743 Get_Name_String (Chars (Node (Component_Elmt)));
745 if Is_Bad_Spelling_Of (Name_Buffer (1 .. Name_Len), S) then
746 Nr_Of_Suggestions := Nr_Of_Suggestions + 1;
748 case Nr_Of_Suggestions is
749 when 1 => Suggestion_1 := Node (Component_Elmt);
750 when 2 => Suggestion_2 := Node (Component_Elmt);
755 Next_Elmt (Component_Elmt);
758 -- Report at most two suggestions
760 if Nr_Of_Suggestions = 1 then
761 Error_Msg_NE ("\possible misspelling of&",
762 Component, Suggestion_1);
764 elsif Nr_Of_Suggestions = 2 then
765 Error_Msg_Node_2 := Suggestion_2;
766 Error_Msg_NE ("\possible misspelling of& or&",
767 Component, Suggestion_1);
770 end Check_Misspelled_Component;
772 ----------------------------------------
773 -- Check_Static_Discriminated_Subtype --
774 ----------------------------------------
776 procedure Check_Static_Discriminated_Subtype (T : Entity_Id; V : Node_Id) is
777 Disc : constant Entity_Id := First_Discriminant (T);
782 if Has_Record_Rep_Clause (T) then
785 elsif Present (Next_Discriminant (Disc)) then
788 elsif Nkind (V) /= N_Integer_Literal then
792 Comp := First_Component (T);
793 while Present (Comp) loop
794 if Is_Scalar_Type (Etype (Comp)) then
797 elsif Is_Private_Type (Etype (Comp))
798 and then Present (Full_View (Etype (Comp)))
799 and then Is_Scalar_Type (Full_View (Etype (Comp)))
803 elsif Is_Array_Type (Etype (Comp)) then
804 if Is_Bit_Packed_Array (Etype (Comp)) then
808 Ind := First_Index (Etype (Comp));
809 while Present (Ind) loop
810 if Nkind (Ind) /= N_Range
811 or else Nkind (Low_Bound (Ind)) /= N_Integer_Literal
812 or else Nkind (High_Bound (Ind)) /= N_Integer_Literal
824 Next_Component (Comp);
827 -- On exit, all components have statically known sizes
829 Set_Size_Known_At_Compile_Time (T);
830 end Check_Static_Discriminated_Subtype;
832 --------------------------------
833 -- Make_String_Into_Aggregate --
834 --------------------------------
836 procedure Make_String_Into_Aggregate (N : Node_Id) is
837 Exprs : constant List_Id := New_List;
838 Loc : constant Source_Ptr := Sloc (N);
839 Str : constant String_Id := Strval (N);
840 Strlen : constant Nat := String_Length (Str);
848 for J in 1 .. Strlen loop
849 C := Get_String_Char (Str, J);
850 Set_Character_Literal_Name (C);
853 Make_Character_Literal (P,
855 Char_Literal_Value => UI_From_CC (C));
856 Set_Etype (C_Node, Any_Character);
857 Append_To (Exprs, C_Node);
860 -- something special for wide strings ???
863 New_N := Make_Aggregate (Loc, Expressions => Exprs);
864 Set_Analyzed (New_N);
865 Set_Etype (New_N, Any_Composite);
868 end Make_String_Into_Aggregate;
870 -----------------------
871 -- Resolve_Aggregate --
872 -----------------------
874 procedure Resolve_Aggregate (N : Node_Id; Typ : Entity_Id) is
875 Pkind : constant Node_Kind := Nkind (Parent (N));
877 Aggr_Subtyp : Entity_Id;
878 -- The actual aggregate subtype. This is not necessarily the same as Typ
879 -- which is the subtype of the context in which the aggregate was found.
882 -- Check for aggregates not allowed in configurable run-time mode.
883 -- We allow all cases of aggregates that do not come from source,
884 -- since these are all assumed to be small (e.g. bounds of a string
885 -- literal). We also allow aggregates of types we know to be small.
887 if not Support_Aggregates_On_Target
888 and then Comes_From_Source (N)
889 and then (not Known_Static_Esize (Typ) or else Esize (Typ) > 64)
891 Error_Msg_CRT ("aggregate", N);
894 -- Ada 2005 (AI-287): Limited aggregates allowed
896 if Is_Limited_Type (Typ) and then Ada_Version < Ada_05 then
897 Error_Msg_N ("aggregate type cannot be limited", N);
898 Explain_Limited_Type (Typ, N);
900 elsif Is_Class_Wide_Type (Typ) then
901 Error_Msg_N ("type of aggregate cannot be class-wide", N);
903 elsif Typ = Any_String
904 or else Typ = Any_Composite
906 Error_Msg_N ("no unique type for aggregate", N);
907 Set_Etype (N, Any_Composite);
909 elsif Is_Array_Type (Typ) and then Null_Record_Present (N) then
910 Error_Msg_N ("null record forbidden in array aggregate", N);
912 elsif Is_Record_Type (Typ) then
913 Resolve_Record_Aggregate (N, Typ);
915 elsif Is_Array_Type (Typ) then
917 -- First a special test, for the case of a positional aggregate
918 -- of characters which can be replaced by a string literal.
919 -- Do not perform this transformation if this was a string literal
920 -- to start with, whose components needed constraint checks, or if
921 -- the component type is non-static, because it will require those
922 -- checks and be transformed back into an aggregate.
924 if Number_Dimensions (Typ) = 1
926 (Root_Type (Component_Type (Typ)) = Standard_Character
928 Root_Type (Component_Type (Typ)) = Standard_Wide_Character
930 Root_Type (Component_Type (Typ)) = Standard_Wide_Wide_Character)
931 and then No (Component_Associations (N))
932 and then not Is_Limited_Composite (Typ)
933 and then not Is_Private_Composite (Typ)
934 and then not Is_Bit_Packed_Array (Typ)
935 and then Nkind (Original_Node (Parent (N))) /= N_String_Literal
936 and then Is_Static_Subtype (Component_Type (Typ))
942 Expr := First (Expressions (N));
943 while Present (Expr) loop
944 exit when Nkind (Expr) /= N_Character_Literal;
951 Expr := First (Expressions (N));
952 while Present (Expr) loop
953 Store_String_Char (UI_To_CC (Char_Literal_Value (Expr)));
958 Make_String_Literal (Sloc (N), End_String));
960 Analyze_And_Resolve (N, Typ);
966 -- Here if we have a real aggregate to deal with
968 Array_Aggregate : declare
969 Aggr_Resolved : Boolean;
971 Aggr_Typ : constant Entity_Id := Etype (Typ);
972 -- This is the unconstrained array type, which is the type
973 -- against which the aggregate is to be resolved. Typ itself
974 -- is the array type of the context which may not be the same
975 -- subtype as the subtype for the final aggregate.
978 -- In the following we determine whether an others choice is
979 -- allowed inside the array aggregate. The test checks the context
980 -- in which the array aggregate occurs. If the context does not
981 -- permit it, or the aggregate type is unconstrained, an others
982 -- choice is not allowed.
984 -- If expansion is disabled (generic context, or semantics-only
985 -- mode) actual subtypes cannot be constructed, and the type of
986 -- an object may be its unconstrained nominal type. However, if
987 -- the context is an assignment, we assume that "others" is
988 -- allowed, because the target of the assignment will have a
989 -- constrained subtype when fully compiled.
991 -- Note that there is no node for Explicit_Actual_Parameter.
992 -- To test for this context we therefore have to test for node
993 -- N_Parameter_Association which itself appears only if there is a
994 -- formal parameter. Consequently we also need to test for
995 -- N_Procedure_Call_Statement or N_Function_Call.
997 Set_Etype (N, Aggr_Typ); -- may be overridden later on
999 if Is_Constrained (Typ) and then
1000 (Pkind = N_Assignment_Statement or else
1001 Pkind = N_Parameter_Association or else
1002 Pkind = N_Function_Call or else
1003 Pkind = N_Procedure_Call_Statement or else
1004 Pkind = N_Generic_Association or else
1005 Pkind = N_Formal_Object_Declaration or else
1006 Pkind = N_Return_Statement or else
1007 Pkind = N_Object_Declaration or else
1008 Pkind = N_Component_Declaration or else
1009 Pkind = N_Parameter_Specification or else
1010 Pkind = N_Qualified_Expression or else
1011 Pkind = N_Aggregate or else
1012 Pkind = N_Extension_Aggregate or else
1013 Pkind = N_Component_Association)
1016 Resolve_Array_Aggregate
1018 Index => First_Index (Aggr_Typ),
1019 Index_Constr => First_Index (Typ),
1020 Component_Typ => Component_Type (Typ),
1021 Others_Allowed => True);
1023 elsif not Expander_Active
1024 and then Pkind = N_Assignment_Statement
1027 Resolve_Array_Aggregate
1029 Index => First_Index (Aggr_Typ),
1030 Index_Constr => First_Index (Typ),
1031 Component_Typ => Component_Type (Typ),
1032 Others_Allowed => True);
1035 Resolve_Array_Aggregate
1037 Index => First_Index (Aggr_Typ),
1038 Index_Constr => First_Index (Aggr_Typ),
1039 Component_Typ => Component_Type (Typ),
1040 Others_Allowed => False);
1043 if not Aggr_Resolved then
1044 Aggr_Subtyp := Any_Composite;
1046 Aggr_Subtyp := Array_Aggr_Subtype (N, Typ);
1049 Set_Etype (N, Aggr_Subtyp);
1050 end Array_Aggregate;
1052 elsif Is_Private_Type (Typ)
1053 and then Present (Full_View (Typ))
1054 and then In_Inlined_Body
1055 and then Is_Composite_Type (Full_View (Typ))
1057 Resolve (N, Full_View (Typ));
1060 Error_Msg_N ("illegal context for aggregate", N);
1063 -- If we can determine statically that the evaluation of the
1064 -- aggregate raises Constraint_Error, then replace the
1065 -- aggregate with an N_Raise_Constraint_Error node, but set the
1066 -- Etype to the right aggregate subtype. Gigi needs this.
1068 if Raises_Constraint_Error (N) then
1069 Aggr_Subtyp := Etype (N);
1071 Make_Raise_Constraint_Error (Sloc (N),
1072 Reason => CE_Range_Check_Failed));
1073 Set_Raises_Constraint_Error (N);
1074 Set_Etype (N, Aggr_Subtyp);
1077 end Resolve_Aggregate;
1079 -----------------------------
1080 -- Resolve_Array_Aggregate --
1081 -----------------------------
1083 function Resolve_Array_Aggregate
1086 Index_Constr : Node_Id;
1087 Component_Typ : Entity_Id;
1088 Others_Allowed : Boolean)
1091 Loc : constant Source_Ptr := Sloc (N);
1093 Failure : constant Boolean := False;
1094 Success : constant Boolean := True;
1096 Index_Typ : constant Entity_Id := Etype (Index);
1097 Index_Typ_Low : constant Node_Id := Type_Low_Bound (Index_Typ);
1098 Index_Typ_High : constant Node_Id := Type_High_Bound (Index_Typ);
1099 -- The type of the index corresponding to the array sub-aggregate
1100 -- along with its low and upper bounds
1102 Index_Base : constant Entity_Id := Base_Type (Index_Typ);
1103 Index_Base_Low : constant Node_Id := Type_Low_Bound (Index_Base);
1104 Index_Base_High : constant Node_Id := Type_High_Bound (Index_Base);
1105 -- ditto for the base type
1107 function Add (Val : Uint; To : Node_Id) return Node_Id;
1108 -- Creates a new expression node where Val is added to expression To.
1109 -- Tries to constant fold whenever possible. To must be an already
1110 -- analyzed expression.
1112 procedure Check_Bound (BH : Node_Id; AH : in out Node_Id);
1113 -- Checks that AH (the upper bound of an array aggregate) is <= BH
1114 -- (the upper bound of the index base type). If the check fails a
1115 -- warning is emitted, the Raises_Constraint_Error Flag of N is set,
1116 -- and AH is replaced with a duplicate of BH.
1118 procedure Check_Bounds (L, H : Node_Id; AL, AH : Node_Id);
1119 -- Checks that range AL .. AH is compatible with range L .. H. Emits a
1120 -- warning if not and sets the Raises_Constraint_Error Flag in N.
1122 procedure Check_Length (L, H : Node_Id; Len : Uint);
1123 -- Checks that range L .. H contains at least Len elements. Emits a
1124 -- warning if not and sets the Raises_Constraint_Error Flag in N.
1126 function Dynamic_Or_Null_Range (L, H : Node_Id) return Boolean;
1127 -- Returns True if range L .. H is dynamic or null
1129 procedure Get (Value : out Uint; From : Node_Id; OK : out Boolean);
1130 -- Given expression node From, this routine sets OK to False if it
1131 -- cannot statically evaluate From. Otherwise it stores this static
1132 -- value into Value.
1134 function Resolve_Aggr_Expr
1136 Single_Elmt : Boolean)
1138 -- Resolves aggregate expression Expr. Returs False if resolution
1139 -- fails. If Single_Elmt is set to False, the expression Expr may be
1140 -- used to initialize several array aggregate elements (this can
1141 -- happen for discrete choices such as "L .. H => Expr" or the others
1142 -- choice). In this event we do not resolve Expr unless expansion is
1143 -- disabled. To know why, see the DELAYED COMPONENT RESOLUTION
1150 function Add (Val : Uint; To : Node_Id) return Node_Id is
1156 if Raises_Constraint_Error (To) then
1160 -- First test if we can do constant folding
1162 if Compile_Time_Known_Value (To)
1163 or else Nkind (To) = N_Integer_Literal
1165 Expr_Pos := Make_Integer_Literal (Loc, Expr_Value (To) + Val);
1166 Set_Is_Static_Expression (Expr_Pos);
1167 Set_Etype (Expr_Pos, Etype (To));
1168 Set_Analyzed (Expr_Pos, Analyzed (To));
1170 if not Is_Enumeration_Type (Index_Typ) then
1173 -- If we are dealing with enumeration return
1174 -- Index_Typ'Val (Expr_Pos)
1178 Make_Attribute_Reference
1180 Prefix => New_Reference_To (Index_Typ, Loc),
1181 Attribute_Name => Name_Val,
1182 Expressions => New_List (Expr_Pos));
1188 -- If we are here no constant folding possible
1190 if not Is_Enumeration_Type (Index_Base) then
1193 Left_Opnd => Duplicate_Subexpr (To),
1194 Right_Opnd => Make_Integer_Literal (Loc, Val));
1196 -- If we are dealing with enumeration return
1197 -- Index_Typ'Val (Index_Typ'Pos (To) + Val)
1201 Make_Attribute_Reference
1203 Prefix => New_Reference_To (Index_Typ, Loc),
1204 Attribute_Name => Name_Pos,
1205 Expressions => New_List (Duplicate_Subexpr (To)));
1209 Left_Opnd => To_Pos,
1210 Right_Opnd => Make_Integer_Literal (Loc, Val));
1213 Make_Attribute_Reference
1215 Prefix => New_Reference_To (Index_Typ, Loc),
1216 Attribute_Name => Name_Val,
1217 Expressions => New_List (Expr_Pos));
1227 procedure Check_Bound (BH : Node_Id; AH : in out Node_Id) is
1235 Get (Value => Val_BH, From => BH, OK => OK_BH);
1236 Get (Value => Val_AH, From => AH, OK => OK_AH);
1238 if OK_BH and then OK_AH and then Val_BH < Val_AH then
1239 Set_Raises_Constraint_Error (N);
1240 Error_Msg_N ("upper bound out of range?", AH);
1241 Error_Msg_N ("\Constraint_Error will be raised at run-time?", AH);
1243 -- You need to set AH to BH or else in the case of enumerations
1244 -- indices we will not be able to resolve the aggregate bounds.
1246 AH := Duplicate_Subexpr (BH);
1254 procedure Check_Bounds (L, H : Node_Id; AL, AH : Node_Id) is
1266 if Raises_Constraint_Error (N)
1267 or else Dynamic_Or_Null_Range (AL, AH)
1272 Get (Value => Val_L, From => L, OK => OK_L);
1273 Get (Value => Val_H, From => H, OK => OK_H);
1275 Get (Value => Val_AL, From => AL, OK => OK_AL);
1276 Get (Value => Val_AH, From => AH, OK => OK_AH);
1278 if OK_L and then Val_L > Val_AL then
1279 Set_Raises_Constraint_Error (N);
1280 Error_Msg_N ("lower bound of aggregate out of range?", N);
1281 Error_Msg_N ("\Constraint_Error will be raised at run-time?", N);
1284 if OK_H and then Val_H < Val_AH then
1285 Set_Raises_Constraint_Error (N);
1286 Error_Msg_N ("upper bound of aggregate out of range?", N);
1287 Error_Msg_N ("\Constraint_Error will be raised at run-time?", N);
1295 procedure Check_Length (L, H : Node_Id; Len : Uint) is
1305 if Raises_Constraint_Error (N) then
1309 Get (Value => Val_L, From => L, OK => OK_L);
1310 Get (Value => Val_H, From => H, OK => OK_H);
1312 if not OK_L or else not OK_H then
1316 -- If null range length is zero
1318 if Val_L > Val_H then
1319 Range_Len := Uint_0;
1321 Range_Len := Val_H - Val_L + 1;
1324 if Range_Len < Len then
1325 Set_Raises_Constraint_Error (N);
1326 Error_Msg_N ("too many elements?", N);
1327 Error_Msg_N ("\Constraint_Error will be raised at run-time?", N);
1331 ---------------------------
1332 -- Dynamic_Or_Null_Range --
1333 ---------------------------
1335 function Dynamic_Or_Null_Range (L, H : Node_Id) return Boolean is
1343 Get (Value => Val_L, From => L, OK => OK_L);
1344 Get (Value => Val_H, From => H, OK => OK_H);
1346 return not OK_L or else not OK_H
1347 or else not Is_OK_Static_Expression (L)
1348 or else not Is_OK_Static_Expression (H)
1349 or else Val_L > Val_H;
1350 end Dynamic_Or_Null_Range;
1356 procedure Get (Value : out Uint; From : Node_Id; OK : out Boolean) is
1360 if Compile_Time_Known_Value (From) then
1361 Value := Expr_Value (From);
1363 -- If expression From is something like Some_Type'Val (10) then
1366 elsif Nkind (From) = N_Attribute_Reference
1367 and then Attribute_Name (From) = Name_Val
1368 and then Compile_Time_Known_Value (First (Expressions (From)))
1370 Value := Expr_Value (First (Expressions (From)));
1378 -----------------------
1379 -- Resolve_Aggr_Expr --
1380 -----------------------
1382 function Resolve_Aggr_Expr
1384 Single_Elmt : Boolean)
1387 Nxt_Ind : constant Node_Id := Next_Index (Index);
1388 Nxt_Ind_Constr : constant Node_Id := Next_Index (Index_Constr);
1389 -- Index is the current index corresponding to the expresion
1391 Resolution_OK : Boolean := True;
1392 -- Set to False if resolution of the expression failed
1395 -- If the array type against which we are resolving the aggregate
1396 -- has several dimensions, the expressions nested inside the
1397 -- aggregate must be further aggregates (or strings).
1399 if Present (Nxt_Ind) then
1400 if Nkind (Expr) /= N_Aggregate then
1402 -- A string literal can appear where a one-dimensional array
1403 -- of characters is expected. If the literal looks like an
1404 -- operator, it is still an operator symbol, which will be
1405 -- transformed into a string when analyzed.
1407 if Is_Character_Type (Component_Typ)
1408 and then No (Next_Index (Nxt_Ind))
1409 and then (Nkind (Expr) = N_String_Literal
1410 or else Nkind (Expr) = N_Operator_Symbol)
1412 -- A string literal used in a multidimensional array
1413 -- aggregate in place of the final one-dimensional
1414 -- aggregate must not be enclosed in parentheses.
1416 if Paren_Count (Expr) /= 0 then
1417 Error_Msg_N ("no parenthesis allowed here", Expr);
1420 Make_String_Into_Aggregate (Expr);
1423 Error_Msg_N ("nested array aggregate expected", Expr);
1428 -- Ada 2005 (AI-231): Propagate the type to the nested aggregate.
1429 -- Required to check the null-exclusion attribute (if present).
1430 -- This value may be overridden later on.
1432 Set_Etype (Expr, Etype (N));
1434 Resolution_OK := Resolve_Array_Aggregate
1435 (Expr, Nxt_Ind, Nxt_Ind_Constr, Component_Typ, Others_Allowed);
1437 -- Do not resolve the expressions of discrete or others choices
1438 -- unless the expression covers a single component, or the expander
1442 or else not Expander_Active
1443 or else In_Default_Expression
1445 Analyze_And_Resolve (Expr, Component_Typ);
1446 Check_Non_Static_Context (Expr);
1447 Aggregate_Constraint_Checks (Expr, Component_Typ);
1448 Check_Unset_Reference (Expr);
1451 if Raises_Constraint_Error (Expr)
1452 and then Nkind (Parent (Expr)) /= N_Component_Association
1454 Set_Raises_Constraint_Error (N);
1457 return Resolution_OK;
1458 end Resolve_Aggr_Expr;
1460 -- Variables local to Resolve_Array_Aggregate
1466 Who_Cares : Node_Id;
1468 Aggr_Low : Node_Id := Empty;
1469 Aggr_High : Node_Id := Empty;
1470 -- The actual low and high bounds of this sub-aggegate
1472 Choices_Low : Node_Id := Empty;
1473 Choices_High : Node_Id := Empty;
1474 -- The lowest and highest discrete choices values for a named aggregate
1476 Nb_Elements : Uint := Uint_0;
1477 -- The number of elements in a positional aggegate
1479 Others_Present : Boolean := False;
1481 Nb_Choices : Nat := 0;
1482 -- Contains the overall number of named choices in this sub-aggregate
1484 Nb_Discrete_Choices : Nat := 0;
1485 -- The overall number of discrete choices (not counting others choice)
1487 Case_Table_Size : Nat;
1488 -- Contains the size of the case table needed to sort aggregate choices
1490 -- Start of processing for Resolve_Array_Aggregate
1493 -- STEP 1: make sure the aggregate is correctly formatted
1495 if Present (Component_Associations (N)) then
1496 Assoc := First (Component_Associations (N));
1497 while Present (Assoc) loop
1498 Choice := First (Choices (Assoc));
1499 while Present (Choice) loop
1500 if Nkind (Choice) = N_Others_Choice then
1501 Others_Present := True;
1503 if Choice /= First (Choices (Assoc))
1504 or else Present (Next (Choice))
1507 ("OTHERS must appear alone in a choice list", Choice);
1511 if Present (Next (Assoc)) then
1513 ("OTHERS must appear last in an aggregate", Choice);
1517 if Ada_Version = Ada_83
1518 and then Assoc /= First (Component_Associations (N))
1519 and then (Nkind (Parent (N)) = N_Assignment_Statement
1521 Nkind (Parent (N)) = N_Object_Declaration)
1524 ("(Ada 83) illegal context for OTHERS choice", N);
1528 Nb_Choices := Nb_Choices + 1;
1536 -- At this point we know that the others choice, if present, is by
1537 -- itself and appears last in the aggregate. Check if we have mixed
1538 -- positional and discrete associations (other than the others choice).
1540 if Present (Expressions (N))
1541 and then (Nb_Choices > 1
1542 or else (Nb_Choices = 1 and then not Others_Present))
1545 ("named association cannot follow positional association",
1546 First (Choices (First (Component_Associations (N)))));
1550 -- Test for the validity of an others choice if present
1552 if Others_Present and then not Others_Allowed then
1554 ("OTHERS choice not allowed here",
1555 First (Choices (First (Component_Associations (N)))));
1559 -- Protect against cascaded errors
1561 if Etype (Index_Typ) = Any_Type then
1565 -- STEP 2: Process named components
1567 if No (Expressions (N)) then
1569 if Others_Present then
1570 Case_Table_Size := Nb_Choices - 1;
1572 Case_Table_Size := Nb_Choices;
1578 -- Denote the lowest and highest values in an aggregate choice
1582 -- High end of one range and Low end of the next. Should be
1583 -- contiguous if there is no hole in the list of values.
1585 Missing_Values : Boolean;
1586 -- Set True if missing index values
1588 S_Low : Node_Id := Empty;
1589 S_High : Node_Id := Empty;
1590 -- if a choice in an aggregate is a subtype indication these
1591 -- denote the lowest and highest values of the subtype
1593 Table : Case_Table_Type (1 .. Case_Table_Size);
1594 -- Used to sort all the different choice values
1596 Single_Choice : Boolean;
1597 -- Set to true every time there is a single discrete choice in a
1598 -- discrete association
1600 Prev_Nb_Discrete_Choices : Nat;
1601 -- Used to keep track of the number of discrete choices
1602 -- in the current association.
1605 -- STEP 2 (A): Check discrete choices validity
1607 Assoc := First (Component_Associations (N));
1608 while Present (Assoc) loop
1609 Prev_Nb_Discrete_Choices := Nb_Discrete_Choices;
1610 Choice := First (Choices (Assoc));
1614 if Nkind (Choice) = N_Others_Choice then
1615 Single_Choice := False;
1618 -- Test for subtype mark without constraint
1620 elsif Is_Entity_Name (Choice) and then
1621 Is_Type (Entity (Choice))
1623 if Base_Type (Entity (Choice)) /= Index_Base then
1625 ("invalid subtype mark in aggregate choice",
1630 elsif Nkind (Choice) = N_Subtype_Indication then
1631 Resolve_Discrete_Subtype_Indication (Choice, Index_Base);
1633 -- Does the subtype indication evaluation raise CE ?
1635 Get_Index_Bounds (Subtype_Mark (Choice), S_Low, S_High);
1636 Get_Index_Bounds (Choice, Low, High);
1637 Check_Bounds (S_Low, S_High, Low, High);
1639 else -- Choice is a range or an expression
1640 Resolve (Choice, Index_Base);
1641 Check_Unset_Reference (Choice);
1642 Check_Non_Static_Context (Choice);
1644 -- Do not range check a choice. This check is redundant
1645 -- since this test is already performed when we check
1646 -- that the bounds of the array aggregate are within
1649 Set_Do_Range_Check (Choice, False);
1652 -- If we could not resolve the discrete choice stop here
1654 if Etype (Choice) = Any_Type then
1657 -- If the discrete choice raises CE get its original bounds
1659 elsif Nkind (Choice) = N_Raise_Constraint_Error then
1660 Set_Raises_Constraint_Error (N);
1661 Get_Index_Bounds (Original_Node (Choice), Low, High);
1663 -- Otherwise get its bounds as usual
1666 Get_Index_Bounds (Choice, Low, High);
1669 if (Dynamic_Or_Null_Range (Low, High)
1670 or else (Nkind (Choice) = N_Subtype_Indication
1672 Dynamic_Or_Null_Range (S_Low, S_High)))
1673 and then Nb_Choices /= 1
1676 ("dynamic or empty choice in aggregate " &
1677 "must be the only choice", Choice);
1681 Nb_Discrete_Choices := Nb_Discrete_Choices + 1;
1682 Table (Nb_Discrete_Choices).Choice_Lo := Low;
1683 Table (Nb_Discrete_Choices).Choice_Hi := High;
1689 -- Check if we have a single discrete choice and whether
1690 -- this discrete choice specifies a single value.
1693 (Nb_Discrete_Choices = Prev_Nb_Discrete_Choices + 1)
1694 and then (Low = High);
1700 -- Ada 2005 (AI-231)
1702 if Ada_Version >= Ada_05
1703 and then Nkind (Expression (Assoc)) = N_Null
1705 Check_Can_Never_Be_Null (Etype (N), Expression (Assoc));
1708 -- Ada 2005 (AI-287): In case of default initialized component
1709 -- we delay the resolution to the expansion phase
1711 if Box_Present (Assoc) then
1713 -- Ada 2005 (AI-287): In case of default initialization
1714 -- of a component the expander will generate calls to
1715 -- the corresponding initialization subprogram.
1719 elsif not Resolve_Aggr_Expr (Expression (Assoc),
1720 Single_Elmt => Single_Choice)
1728 -- If aggregate contains more than one choice then these must be
1729 -- static. Sort them and check that they are contiguous
1731 if Nb_Discrete_Choices > 1 then
1732 Sort_Case_Table (Table);
1733 Missing_Values := False;
1735 Outer : for J in 1 .. Nb_Discrete_Choices - 1 loop
1736 if Expr_Value (Table (J).Choice_Hi) >=
1737 Expr_Value (Table (J + 1).Choice_Lo)
1740 ("duplicate choice values in array aggregate",
1741 Table (J).Choice_Hi);
1744 elsif not Others_Present then
1746 Hi_Val := Expr_Value (Table (J).Choice_Hi);
1747 Lo_Val := Expr_Value (Table (J + 1).Choice_Lo);
1749 -- If missing values, output error messages
1751 if Lo_Val - Hi_Val > 1 then
1753 -- Header message if not first missing value
1755 if not Missing_Values then
1757 ("missing index value(s) in array aggregate", N);
1758 Missing_Values := True;
1761 -- Output values of missing indexes
1763 Lo_Val := Lo_Val - 1;
1764 Hi_Val := Hi_Val + 1;
1766 -- Enumeration type case
1768 if Is_Enumeration_Type (Index_Typ) then
1771 (Get_Enum_Lit_From_Pos
1772 (Index_Typ, Hi_Val, Loc));
1774 if Lo_Val = Hi_Val then
1775 Error_Msg_N ("\ %", N);
1779 (Get_Enum_Lit_From_Pos
1780 (Index_Typ, Lo_Val, Loc));
1781 Error_Msg_N ("\ % .. %", N);
1784 -- Integer types case
1787 Error_Msg_Uint_1 := Hi_Val;
1789 if Lo_Val = Hi_Val then
1790 Error_Msg_N ("\ ^", N);
1792 Error_Msg_Uint_2 := Lo_Val;
1793 Error_Msg_N ("\ ^ .. ^", N);
1800 if Missing_Values then
1801 Set_Etype (N, Any_Composite);
1806 -- STEP 2 (B): Compute aggregate bounds and min/max choices values
1808 if Nb_Discrete_Choices > 0 then
1809 Choices_Low := Table (1).Choice_Lo;
1810 Choices_High := Table (Nb_Discrete_Choices).Choice_Hi;
1813 if Others_Present then
1814 Get_Index_Bounds (Index_Constr, Aggr_Low, Aggr_High);
1817 Aggr_Low := Choices_Low;
1818 Aggr_High := Choices_High;
1822 -- STEP 3: Process positional components
1825 -- STEP 3 (A): Process positional elements
1827 Expr := First (Expressions (N));
1828 Nb_Elements := Uint_0;
1829 while Present (Expr) loop
1830 Nb_Elements := Nb_Elements + 1;
1832 -- Ada 2005 (AI-231)
1834 if Ada_Version >= Ada_05
1835 and then Nkind (Expr) = N_Null
1837 Check_Can_Never_Be_Null (Etype (N), Expr);
1840 if not Resolve_Aggr_Expr (Expr, Single_Elmt => True) then
1847 if Others_Present then
1848 Assoc := Last (Component_Associations (N));
1850 -- Ada 2005 (AI-231)
1852 if Ada_Version >= Ada_05
1853 and then Nkind (Assoc) = N_Null
1855 Check_Can_Never_Be_Null (Etype (N), Expression (Assoc));
1858 -- Ada 2005 (AI-287): In case of default initialized component
1859 -- we delay the resolution to the expansion phase.
1861 if Box_Present (Assoc) then
1863 -- Ada 2005 (AI-287): In case of default initialization
1864 -- of a component the expander will generate calls to
1865 -- the corresponding initialization subprogram.
1869 elsif not Resolve_Aggr_Expr (Expression (Assoc),
1870 Single_Elmt => False)
1876 -- STEP 3 (B): Compute the aggregate bounds
1878 if Others_Present then
1879 Get_Index_Bounds (Index_Constr, Aggr_Low, Aggr_High);
1882 if Others_Allowed then
1883 Get_Index_Bounds (Index_Constr, Aggr_Low, Who_Cares);
1885 Aggr_Low := Index_Typ_Low;
1888 Aggr_High := Add (Nb_Elements - 1, To => Aggr_Low);
1889 Check_Bound (Index_Base_High, Aggr_High);
1893 -- STEP 4: Perform static aggregate checks and save the bounds
1897 Check_Bounds (Index_Typ_Low, Index_Typ_High, Aggr_Low, Aggr_High);
1898 Check_Bounds (Index_Base_Low, Index_Base_High, Aggr_Low, Aggr_High);
1902 if Others_Present and then Nb_Discrete_Choices > 0 then
1903 Check_Bounds (Aggr_Low, Aggr_High, Choices_Low, Choices_High);
1904 Check_Bounds (Index_Typ_Low, Index_Typ_High,
1905 Choices_Low, Choices_High);
1906 Check_Bounds (Index_Base_Low, Index_Base_High,
1907 Choices_Low, Choices_High);
1911 elsif Others_Present and then Nb_Elements > 0 then
1912 Check_Length (Aggr_Low, Aggr_High, Nb_Elements);
1913 Check_Length (Index_Typ_Low, Index_Typ_High, Nb_Elements);
1914 Check_Length (Index_Base_Low, Index_Base_High, Nb_Elements);
1917 if Raises_Constraint_Error (Aggr_Low)
1918 or else Raises_Constraint_Error (Aggr_High)
1920 Set_Raises_Constraint_Error (N);
1923 Aggr_Low := Duplicate_Subexpr (Aggr_Low);
1925 -- Do not duplicate Aggr_High if Aggr_High = Aggr_Low + Nb_Elements
1926 -- since the addition node returned by Add is not yet analyzed. Attach
1927 -- to tree and analyze first. Reset analyzed flag to insure it will get
1928 -- analyzed when it is a literal bound whose type must be properly set.
1930 if Others_Present or else Nb_Discrete_Choices > 0 then
1931 Aggr_High := Duplicate_Subexpr (Aggr_High);
1933 if Etype (Aggr_High) = Universal_Integer then
1934 Set_Analyzed (Aggr_High, False);
1938 Set_Aggregate_Bounds
1939 (N, Make_Range (Loc, Low_Bound => Aggr_Low, High_Bound => Aggr_High));
1941 -- The bounds may contain expressions that must be inserted upwards.
1942 -- Attach them fully to the tree. After analysis, remove side effects
1943 -- from upper bound, if still needed.
1945 Set_Parent (Aggregate_Bounds (N), N);
1946 Analyze_And_Resolve (Aggregate_Bounds (N), Index_Typ);
1947 Check_Unset_Reference (Aggregate_Bounds (N));
1949 if not Others_Present and then Nb_Discrete_Choices = 0 then
1950 Set_High_Bound (Aggregate_Bounds (N),
1951 Duplicate_Subexpr (High_Bound (Aggregate_Bounds (N))));
1955 end Resolve_Array_Aggregate;
1957 ---------------------------------
1958 -- Resolve_Extension_Aggregate --
1959 ---------------------------------
1961 -- There are two cases to consider:
1963 -- a) If the ancestor part is a type mark, the components needed are
1964 -- the difference between the components of the expected type and the
1965 -- components of the given type mark.
1967 -- b) If the ancestor part is an expression, it must be unambiguous,
1968 -- and once we have its type we can also compute the needed components
1969 -- as in the previous case. In both cases, if the ancestor type is not
1970 -- the immediate ancestor, we have to build this ancestor recursively.
1972 -- In both cases discriminants of the ancestor type do not play a
1973 -- role in the resolution of the needed components, because inherited
1974 -- discriminants cannot be used in a type extension. As a result we can
1975 -- compute independently the list of components of the ancestor type and
1976 -- of the expected type.
1978 procedure Resolve_Extension_Aggregate (N : Node_Id; Typ : Entity_Id) is
1979 A : constant Node_Id := Ancestor_Part (N);
1984 function Valid_Ancestor_Type return Boolean;
1985 -- Verify that the type of the ancestor part is a non-private ancestor
1986 -- of the expected type.
1988 -------------------------
1989 -- Valid_Ancestor_Type --
1990 -------------------------
1992 function Valid_Ancestor_Type return Boolean is
1993 Imm_Type : Entity_Id;
1996 Imm_Type := Base_Type (Typ);
1997 while Is_Derived_Type (Imm_Type)
1998 and then Etype (Imm_Type) /= Base_Type (A_Type)
2000 Imm_Type := Etype (Base_Type (Imm_Type));
2003 if Etype (Imm_Type) /= Base_Type (A_Type) then
2004 Error_Msg_NE ("expect ancestor type of &", A, Typ);
2009 end Valid_Ancestor_Type;
2011 -- Start of processing for Resolve_Extension_Aggregate
2016 if not Is_Tagged_Type (Typ) then
2017 Error_Msg_N ("type of extension aggregate must be tagged", N);
2020 elsif Is_Limited_Type (Typ) then
2022 -- Ada 2005 (AI-287): Limited aggregates are allowed
2024 if Ada_Version < Ada_05 then
2025 Error_Msg_N ("aggregate type cannot be limited", N);
2026 Explain_Limited_Type (Typ, N);
2030 elsif Is_Class_Wide_Type (Typ) then
2031 Error_Msg_N ("aggregate cannot be of a class-wide type", N);
2035 if Is_Entity_Name (A)
2036 and then Is_Type (Entity (A))
2038 A_Type := Get_Full_View (Entity (A));
2040 if Valid_Ancestor_Type then
2041 Set_Entity (A, A_Type);
2042 Set_Etype (A, A_Type);
2044 Validate_Ancestor_Part (N);
2045 Resolve_Record_Aggregate (N, Typ);
2048 elsif Nkind (A) /= N_Aggregate then
2049 if Is_Overloaded (A) then
2052 Get_First_Interp (A, I, It);
2053 while Present (It.Typ) loop
2054 if Is_Tagged_Type (It.Typ)
2055 and then not Is_Limited_Type (It.Typ)
2057 if A_Type /= Any_Type then
2058 Error_Msg_N ("cannot resolve expression", A);
2065 Get_Next_Interp (I, It);
2068 if A_Type = Any_Type then
2070 ("ancestor part must be non-limited tagged type", A);
2075 A_Type := Etype (A);
2078 if Valid_Ancestor_Type then
2079 Resolve (A, A_Type);
2080 Check_Unset_Reference (A);
2081 Check_Non_Static_Context (A);
2083 if Is_Class_Wide_Type (Etype (A))
2084 and then Nkind (Original_Node (A)) = N_Function_Call
2086 -- If the ancestor part is a dispatching call, it appears
2087 -- statically to be a legal ancestor, but it yields any
2088 -- member of the class, and it is not possible to determine
2089 -- whether it is an ancestor of the extension aggregate (much
2090 -- less which ancestor). It is not possible to determine the
2091 -- required components of the extension part.
2093 -- This check implements AI-306, which in fact was motivated
2094 -- by an ACT query to the ARG after this test was added.
2096 Error_Msg_N ("ancestor part must be statically tagged", A);
2098 Resolve_Record_Aggregate (N, Typ);
2103 Error_Msg_N ("no unique type for this aggregate", A);
2105 end Resolve_Extension_Aggregate;
2107 ------------------------------
2108 -- Resolve_Record_Aggregate --
2109 ------------------------------
2111 procedure Resolve_Record_Aggregate (N : Node_Id; Typ : Entity_Id) is
2113 -- N_Component_Association node belonging to the input aggregate N
2116 Positional_Expr : Node_Id;
2117 Component : Entity_Id;
2118 Component_Elmt : Elmt_Id;
2120 Components : constant Elist_Id := New_Elmt_List;
2121 -- Components is the list of the record components whose value must
2122 -- be provided in the aggregate. This list does include discriminants.
2124 New_Assoc_List : constant List_Id := New_List;
2125 New_Assoc : Node_Id;
2126 -- New_Assoc_List is the newly built list of N_Component_Association
2127 -- nodes. New_Assoc is one such N_Component_Association node in it.
2128 -- Please note that while Assoc and New_Assoc contain the same
2129 -- kind of nodes, they are used to iterate over two different
2130 -- N_Component_Association lists.
2132 Others_Etype : Entity_Id := Empty;
2133 -- This variable is used to save the Etype of the last record component
2134 -- that takes its value from the others choice. Its purpose is:
2136 -- (a) make sure the others choice is useful
2138 -- (b) make sure the type of all the components whose value is
2139 -- subsumed by the others choice are the same.
2141 -- This variable is updated as a side effect of function Get_Value
2143 Is_Box_Present : Boolean := False;
2144 Others_Box : Boolean := False;
2145 -- Ada 2005 (AI-287): Variables used in case of default initialization
2146 -- to provide a functionality similar to Others_Etype. Box_Present
2147 -- indicates that the component takes its default initialization;
2148 -- Others_Box indicates that at least one component takes its default
2149 -- initialization. Similar to Others_Etype, they are also updated as a
2150 -- side effect of function Get_Value.
2152 procedure Add_Association
2153 (Component : Entity_Id;
2155 Is_Box_Present : Boolean := False);
2156 -- Builds a new N_Component_Association node which associates
2157 -- Component to expression Expr and adds it to the new association
2158 -- list New_Assoc_List being built.
2160 function Discr_Present (Discr : Entity_Id) return Boolean;
2161 -- If aggregate N is a regular aggregate this routine will return True.
2162 -- Otherwise, if N is an extension aggregate, Discr is a discriminant
2163 -- whose value may already have been specified by N's ancestor part,
2164 -- this routine checks whether this is indeed the case and if so
2165 -- returns False, signaling that no value for Discr should appear in the
2166 -- N's aggregate part. Also, in this case, the routine appends to
2167 -- New_Assoc_List Discr the discriminant value specified in the ancestor
2173 Consider_Others_Choice : Boolean := False)
2175 -- Given a record component stored in parameter Compon, the
2176 -- following function returns its value as it appears in the list
2177 -- From, which is a list of N_Component_Association nodes. If no
2178 -- component association has a choice for the searched component,
2179 -- the value provided by the others choice is returned, if there
2180 -- is one and Consider_Others_Choice is set to true. Otherwise
2181 -- Empty is returned. If there is more than one component association
2182 -- giving a value for the searched record component, an error message
2183 -- is emitted and the first found value is returned.
2185 -- If Consider_Others_Choice is set and the returned expression comes
2186 -- from the others choice, then Others_Etype is set as a side effect.
2187 -- An error message is emitted if the components taking their value
2188 -- from the others choice do not have same type.
2190 procedure Resolve_Aggr_Expr (Expr : Node_Id; Component : Node_Id);
2191 -- Analyzes and resolves expression Expr against the Etype of the
2192 -- Component. This routine also applies all appropriate checks to Expr.
2193 -- It finally saves a Expr in the newly created association list that
2194 -- will be attached to the final record aggregate. Note that if the
2195 -- Parent pointer of Expr is not set then Expr was produced with a
2196 -- New_Copy_Tree or some such.
2198 ---------------------
2199 -- Add_Association --
2200 ---------------------
2202 procedure Add_Association
2203 (Component : Entity_Id;
2205 Is_Box_Present : Boolean := False)
2207 Choice_List : constant List_Id := New_List;
2208 New_Assoc : Node_Id;
2211 Append (New_Occurrence_Of (Component, Sloc (Expr)), Choice_List);
2213 Make_Component_Association (Sloc (Expr),
2214 Choices => Choice_List,
2216 Box_Present => Is_Box_Present);
2217 Append (New_Assoc, New_Assoc_List);
2218 end Add_Association;
2224 function Discr_Present (Discr : Entity_Id) return Boolean is
2225 Regular_Aggr : constant Boolean := Nkind (N) /= N_Extension_Aggregate;
2230 Discr_Expr : Node_Id;
2232 Ancestor_Typ : Entity_Id;
2233 Orig_Discr : Entity_Id;
2235 D_Val : Elmt_Id := No_Elmt; -- stop junk warning
2237 Ancestor_Is_Subtyp : Boolean;
2240 if Regular_Aggr then
2244 Ancestor := Ancestor_Part (N);
2245 Ancestor_Typ := Etype (Ancestor);
2246 Loc := Sloc (Ancestor);
2248 Ancestor_Is_Subtyp :=
2249 Is_Entity_Name (Ancestor) and then Is_Type (Entity (Ancestor));
2251 -- If the ancestor part has no discriminants clearly N's aggregate
2252 -- part must provide a value for Discr.
2254 if not Has_Discriminants (Ancestor_Typ) then
2257 -- If the ancestor part is an unconstrained subtype mark then the
2258 -- Discr must be present in N's aggregate part.
2260 elsif Ancestor_Is_Subtyp
2261 and then not Is_Constrained (Entity (Ancestor))
2266 -- Now look to see if Discr was specified in the ancestor part
2268 if Ancestor_Is_Subtyp then
2269 D_Val := First_Elmt (Discriminant_Constraint (Entity (Ancestor)));
2272 Orig_Discr := Original_Record_Component (Discr);
2274 D := First_Discriminant (Ancestor_Typ);
2275 while Present (D) loop
2277 -- If Ancestor has already specified Disc value than insert its
2278 -- value in the final aggregate.
2280 if Original_Record_Component (D) = Orig_Discr then
2281 if Ancestor_Is_Subtyp then
2282 Discr_Expr := New_Copy_Tree (Node (D_Val));
2285 Make_Selected_Component (Loc,
2286 Prefix => Duplicate_Subexpr (Ancestor),
2287 Selector_Name => New_Occurrence_Of (Discr, Loc));
2290 Resolve_Aggr_Expr (Discr_Expr, Discr);
2294 Next_Discriminant (D);
2296 if Ancestor_Is_Subtyp then
2311 Consider_Others_Choice : Boolean := False)
2315 Expr : Node_Id := Empty;
2316 Selector_Name : Node_Id;
2319 Is_Box_Present := False;
2321 if Present (From) then
2322 Assoc := First (From);
2327 while Present (Assoc) loop
2328 Selector_Name := First (Choices (Assoc));
2329 while Present (Selector_Name) loop
2330 if Nkind (Selector_Name) = N_Others_Choice then
2331 if Consider_Others_Choice and then No (Expr) then
2333 -- We need to duplicate the expression for each
2334 -- successive component covered by the others choice.
2335 -- This is redundant if the others_choice covers only
2336 -- one component (small optimization possible???), but
2337 -- indispensable otherwise, because each one must be
2338 -- expanded individually to preserve side-effects.
2340 -- Ada 2005 (AI-287): In case of default initialization
2341 -- of components, we duplicate the corresponding default
2342 -- expression (from the record type declaration). The
2343 -- copy must carry the sloc of the association (not the
2344 -- original expression) to prevent spurious elaboration
2345 -- checks when the default includes function calls.
2347 if Box_Present (Assoc) then
2349 Is_Box_Present := True;
2351 if Expander_Active then
2354 (Expression (Parent (Compon)),
2355 New_Sloc => Sloc (Assoc));
2357 return Expression (Parent (Compon));
2361 if Present (Others_Etype) and then
2362 Base_Type (Others_Etype) /= Base_Type (Etype
2365 Error_Msg_N ("components in OTHERS choice must " &
2366 "have same type", Selector_Name);
2369 Others_Etype := Etype (Compon);
2371 if Expander_Active then
2372 return New_Copy_Tree (Expression (Assoc));
2374 return Expression (Assoc);
2379 elsif Chars (Compon) = Chars (Selector_Name) then
2382 -- Ada 2005 (AI-231)
2384 if Ada_Version >= Ada_05
2385 and then Nkind (Expression (Assoc)) = N_Null
2387 Check_Can_Never_Be_Null (Compon, Expression (Assoc));
2390 -- We need to duplicate the expression when several
2391 -- components are grouped together with a "|" choice.
2392 -- For instance "filed1 | filed2 => Expr"
2394 -- Ada 2005 (AI-287)
2396 if Box_Present (Assoc) then
2397 Is_Box_Present := True;
2399 -- Duplicate the default expression of the component
2400 -- from the record type declaration
2402 if Present (Next (Selector_Name)) then
2404 New_Copy_Tree (Expression (Parent (Compon)));
2406 Expr := Expression (Parent (Compon));
2410 if Present (Next (Selector_Name)) then
2411 Expr := New_Copy_Tree (Expression (Assoc));
2413 Expr := Expression (Assoc);
2417 Generate_Reference (Compon, Selector_Name);
2421 ("more than one value supplied for &",
2422 Selector_Name, Compon);
2427 Next (Selector_Name);
2436 procedure Check_Non_Limited_Type (Expr : Node_Id);
2437 -- Relax check to allow the default initialization of limited types.
2440 -- C : Lim := (..., others => <>);
2443 ----------------------------
2444 -- Check_Non_Limited_Type --
2445 ----------------------------
2447 procedure Check_Non_Limited_Type (Expr : Node_Id) is
2449 if Is_Limited_Type (Etype (Expr))
2450 and then Comes_From_Source (Expr)
2451 and then not In_Instance_Body
2453 if not OK_For_Limited_Init (Expr) then
2455 ("initialization not allowed for limited types", N);
2456 Explain_Limited_Type (Etype (Expr), Expr);
2459 end Check_Non_Limited_Type;
2461 -----------------------
2462 -- Resolve_Aggr_Expr --
2463 -----------------------
2465 procedure Resolve_Aggr_Expr (Expr : Node_Id; Component : Node_Id) is
2466 New_C : Entity_Id := Component;
2467 Expr_Type : Entity_Id := Empty;
2469 function Has_Expansion_Delayed (Expr : Node_Id) return Boolean;
2470 -- If the expression is an aggregate (possibly qualified) then its
2471 -- expansion is delayed until the enclosing aggregate is expanded
2472 -- into assignments. In that case, do not generate checks on the
2473 -- expression, because they will be generated later, and will other-
2474 -- wise force a copy (to remove side-effects) that would leave a
2475 -- dynamic-sized aggregate in the code, something that gigi cannot
2479 -- Set to True if the resolved Expr node needs to be relocated
2480 -- when attached to the newly created association list. This node
2481 -- need not be relocated if its parent pointer is not set.
2482 -- In fact in this case Expr is the output of a New_Copy_Tree call.
2483 -- if Relocate is True then we have analyzed the expression node
2484 -- in the original aggregate and hence it needs to be relocated
2485 -- when moved over the new association list.
2487 function Has_Expansion_Delayed (Expr : Node_Id) return Boolean is
2488 Kind : constant Node_Kind := Nkind (Expr);
2491 return ((Kind = N_Aggregate
2492 or else Kind = N_Extension_Aggregate)
2493 and then Present (Etype (Expr))
2494 and then Is_Record_Type (Etype (Expr))
2495 and then Expansion_Delayed (Expr))
2497 or else (Kind = N_Qualified_Expression
2498 and then Has_Expansion_Delayed (Expression (Expr)));
2499 end Has_Expansion_Delayed;
2501 -- Start of processing for Resolve_Aggr_Expr
2504 -- If the type of the component is elementary or the type of the
2505 -- aggregate does not contain discriminants, use the type of the
2506 -- component to resolve Expr.
2508 if Is_Elementary_Type (Etype (Component))
2509 or else not Has_Discriminants (Etype (N))
2511 Expr_Type := Etype (Component);
2513 -- Otherwise we have to pick up the new type of the component from
2514 -- the new costrained subtype of the aggregate. In fact components
2515 -- which are of a composite type might be constrained by a
2516 -- discriminant, and we want to resolve Expr against the subtype were
2517 -- all discriminant occurrences are replaced with their actual value.
2520 New_C := First_Component (Etype (N));
2521 while Present (New_C) loop
2522 if Chars (New_C) = Chars (Component) then
2523 Expr_Type := Etype (New_C);
2527 Next_Component (New_C);
2530 pragma Assert (Present (Expr_Type));
2532 -- For each range in an array type where a discriminant has been
2533 -- replaced with the constraint, check that this range is within
2534 -- the range of the base type. This checks is done in the init
2535 -- proc for regular objects, but has to be done here for
2536 -- aggregates since no init proc is called for them.
2538 if Is_Array_Type (Expr_Type) then
2541 -- Range of the current constrained index in the array
2543 Orig_Index : Node_Id := First_Index (Etype (Component));
2544 -- Range corresponding to the range Index above in the
2545 -- original unconstrained record type. The bounds of this
2546 -- range may be governed by discriminants.
2548 Unconstr_Index : Node_Id := First_Index (Etype (Expr_Type));
2549 -- Range corresponding to the range Index above for the
2550 -- unconstrained array type. This range is needed to apply
2554 Index := First_Index (Expr_Type);
2555 while Present (Index) loop
2556 if Depends_On_Discriminant (Orig_Index) then
2557 Apply_Range_Check (Index, Etype (Unconstr_Index));
2561 Next_Index (Orig_Index);
2562 Next_Index (Unconstr_Index);
2568 -- If the Parent pointer of Expr is not set, Expr is an expression
2569 -- duplicated by New_Tree_Copy (this happens for record aggregates
2570 -- that look like (Field1 | Filed2 => Expr) or (others => Expr)).
2571 -- Such a duplicated expression must be attached to the tree
2572 -- before analysis and resolution to enforce the rule that a tree
2573 -- fragment should never be analyzed or resolved unless it is
2574 -- attached to the current compilation unit.
2576 if No (Parent (Expr)) then
2577 Set_Parent (Expr, N);
2583 Analyze_And_Resolve (Expr, Expr_Type);
2584 Check_Non_Limited_Type (Expr);
2585 Check_Non_Static_Context (Expr);
2586 Check_Unset_Reference (Expr);
2588 if not Has_Expansion_Delayed (Expr) then
2589 Aggregate_Constraint_Checks (Expr, Expr_Type);
2592 if Raises_Constraint_Error (Expr) then
2593 Set_Raises_Constraint_Error (N);
2597 Add_Association (New_C, Relocate_Node (Expr));
2599 Add_Association (New_C, Expr);
2601 end Resolve_Aggr_Expr;
2603 -- Start of processing for Resolve_Record_Aggregate
2606 -- We may end up calling Duplicate_Subexpr on expressions that are
2607 -- attached to New_Assoc_List. For this reason we need to attach it
2608 -- to the tree by setting its parent pointer to N. This parent point
2609 -- will change in STEP 8 below.
2611 Set_Parent (New_Assoc_List, N);
2613 -- STEP 1: abstract type and null record verification
2615 if Is_Abstract_Type (Typ) then
2616 Error_Msg_N ("type of aggregate cannot be abstract", N);
2619 if No (First_Entity (Typ)) and then Null_Record_Present (N) then
2623 elsif Present (First_Entity (Typ))
2624 and then Null_Record_Present (N)
2625 and then not Is_Tagged_Type (Typ)
2627 Error_Msg_N ("record aggregate cannot be null", N);
2630 elsif No (First_Entity (Typ)) then
2631 Error_Msg_N ("record aggregate must be null", N);
2635 -- STEP 2: Verify aggregate structure
2638 Selector_Name : Node_Id;
2639 Bad_Aggregate : Boolean := False;
2642 if Present (Component_Associations (N)) then
2643 Assoc := First (Component_Associations (N));
2648 while Present (Assoc) loop
2649 Selector_Name := First (Choices (Assoc));
2650 while Present (Selector_Name) loop
2651 if Nkind (Selector_Name) = N_Identifier then
2654 elsif Nkind (Selector_Name) = N_Others_Choice then
2655 if Selector_Name /= First (Choices (Assoc))
2656 or else Present (Next (Selector_Name))
2658 Error_Msg_N ("OTHERS must appear alone in a choice list",
2662 elsif Present (Next (Assoc)) then
2663 Error_Msg_N ("OTHERS must appear last in an aggregate",
2670 ("selector name should be identifier or OTHERS",
2672 Bad_Aggregate := True;
2675 Next (Selector_Name);
2681 if Bad_Aggregate then
2686 -- STEP 3: Find discriminant Values
2689 Discrim : Entity_Id;
2690 Missing_Discriminants : Boolean := False;
2693 if Present (Expressions (N)) then
2694 Positional_Expr := First (Expressions (N));
2696 Positional_Expr := Empty;
2699 if Has_Discriminants (Typ) then
2700 Discrim := First_Discriminant (Typ);
2705 -- First find the discriminant values in the positional components
2707 while Present (Discrim) and then Present (Positional_Expr) loop
2708 if Discr_Present (Discrim) then
2709 Resolve_Aggr_Expr (Positional_Expr, Discrim);
2711 -- Ada 2005 (AI-231)
2713 if Ada_Version >= Ada_05
2714 and then Nkind (Positional_Expr) = N_Null
2716 Check_Can_Never_Be_Null (Discrim, Positional_Expr);
2719 Next (Positional_Expr);
2722 if Present (Get_Value (Discrim, Component_Associations (N))) then
2724 ("more than one value supplied for discriminant&",
2728 Next_Discriminant (Discrim);
2731 -- Find remaining discriminant values, if any, among named components
2733 while Present (Discrim) loop
2734 Expr := Get_Value (Discrim, Component_Associations (N), True);
2736 if not Discr_Present (Discrim) then
2737 if Present (Expr) then
2739 ("more than one value supplied for discriminant&",
2743 elsif No (Expr) then
2745 ("no value supplied for discriminant &", N, Discrim);
2746 Missing_Discriminants := True;
2749 Resolve_Aggr_Expr (Expr, Discrim);
2752 Next_Discriminant (Discrim);
2755 if Missing_Discriminants then
2759 -- At this point and until the beginning of STEP 6, New_Assoc_List
2760 -- contains only the discriminants and their values.
2764 -- STEP 4: Set the Etype of the record aggregate
2766 -- ??? This code is pretty much a copy of Sem_Ch3.Build_Subtype. That
2767 -- routine should really be exported in sem_util or some such and used
2768 -- in sem_ch3 and here rather than have a copy of the code which is a
2769 -- maintenance nightmare.
2771 -- ??? Performace WARNING. The current implementation creates a new
2772 -- itype for all aggregates whose base type is discriminated.
2773 -- This means that for record aggregates nested inside an array
2774 -- aggregate we will create a new itype for each record aggregate
2775 -- if the array cmponent type has discriminants. For large aggregates
2776 -- this may be a problem. What should be done in this case is
2777 -- to reuse itypes as much as possible.
2779 if Has_Discriminants (Typ) then
2780 Build_Constrained_Itype : declare
2781 Loc : constant Source_Ptr := Sloc (N);
2783 Subtyp_Decl : Node_Id;
2786 C : constant List_Id := New_List;
2789 New_Assoc := First (New_Assoc_List);
2790 while Present (New_Assoc) loop
2791 Append (Duplicate_Subexpr (Expression (New_Assoc)), To => C);
2796 Make_Subtype_Indication (Loc,
2797 Subtype_Mark => New_Occurrence_Of (Base_Type (Typ), Loc),
2798 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
2800 Def_Id := Create_Itype (Ekind (Typ), N);
2803 Make_Subtype_Declaration (Loc,
2804 Defining_Identifier => Def_Id,
2805 Subtype_Indication => Indic);
2806 Set_Parent (Subtyp_Decl, Parent (N));
2808 -- Itypes must be analyzed with checks off (see itypes.ads)
2810 Analyze (Subtyp_Decl, Suppress => All_Checks);
2812 Set_Etype (N, Def_Id);
2813 Check_Static_Discriminated_Subtype
2814 (Def_Id, Expression (First (New_Assoc_List)));
2815 end Build_Constrained_Itype;
2821 -- STEP 5: Get remaining components according to discriminant values
2824 Record_Def : Node_Id;
2825 Parent_Typ : Entity_Id;
2826 Root_Typ : Entity_Id;
2827 Parent_Typ_List : Elist_Id;
2828 Parent_Elmt : Elmt_Id;
2829 Errors_Found : Boolean := False;
2833 if Is_Derived_Type (Typ) and then Is_Tagged_Type (Typ) then
2834 Parent_Typ_List := New_Elmt_List;
2836 -- If this is an extension aggregate, the component list must
2837 -- include all components that are not in the given ancestor
2838 -- type. Otherwise, the component list must include components
2839 -- of all ancestors, starting with the root.
2841 if Nkind (N) = N_Extension_Aggregate then
2842 Root_Typ := Base_Type (Etype (Ancestor_Part (N)));
2844 Root_Typ := Root_Type (Typ);
2846 if Nkind (Parent (Base_Type (Root_Typ)))
2847 = N_Private_Type_Declaration
2850 ("type of aggregate has private ancestor&!",
2852 Error_Msg_N ("must use extension aggregate!", N);
2856 Dnode := Declaration_Node (Base_Type (Root_Typ));
2858 -- If we don't get a full declaration, then we have some
2859 -- error which will get signalled later so skip this part.
2860 -- Otherwise, gather components of root that apply to the
2861 -- aggregate type. We use the base type in case there is an
2862 -- applicable stored constraint that renames the discriminants
2865 if Nkind (Dnode) = N_Full_Type_Declaration then
2866 Record_Def := Type_Definition (Dnode);
2867 Gather_Components (Base_Type (Typ),
2868 Component_List (Record_Def),
2869 Governed_By => New_Assoc_List,
2871 Report_Errors => Errors_Found);
2875 Parent_Typ := Base_Type (Typ);
2876 while Parent_Typ /= Root_Typ loop
2877 Prepend_Elmt (Parent_Typ, To => Parent_Typ_List);
2878 Parent_Typ := Etype (Parent_Typ);
2880 if Nkind (Parent (Base_Type (Parent_Typ))) =
2881 N_Private_Type_Declaration
2882 or else Nkind (Parent (Base_Type (Parent_Typ))) =
2883 N_Private_Extension_Declaration
2885 if Nkind (N) /= N_Extension_Aggregate then
2887 ("type of aggregate has private ancestor&!",
2889 Error_Msg_N ("must use extension aggregate!", N);
2892 elsif Parent_Typ /= Root_Typ then
2894 ("ancestor part of aggregate must be private type&",
2895 Ancestor_Part (N), Parent_Typ);
2901 -- Now collect components from all other ancestors
2903 Parent_Elmt := First_Elmt (Parent_Typ_List);
2904 while Present (Parent_Elmt) loop
2905 Parent_Typ := Node (Parent_Elmt);
2906 Record_Def := Type_Definition (Parent (Base_Type (Parent_Typ)));
2907 Gather_Components (Empty,
2908 Component_List (Record_Extension_Part (Record_Def)),
2909 Governed_By => New_Assoc_List,
2911 Report_Errors => Errors_Found);
2913 Next_Elmt (Parent_Elmt);
2917 Record_Def := Type_Definition (Parent (Base_Type (Typ)));
2919 if Null_Present (Record_Def) then
2922 Gather_Components (Base_Type (Typ),
2923 Component_List (Record_Def),
2924 Governed_By => New_Assoc_List,
2926 Report_Errors => Errors_Found);
2930 if Errors_Found then
2935 -- STEP 6: Find component Values
2938 Component_Elmt := First_Elmt (Components);
2940 -- First scan the remaining positional associations in the aggregate.
2941 -- Remember that at this point Positional_Expr contains the current
2942 -- positional association if any is left after looking for discriminant
2943 -- values in step 3.
2945 while Present (Positional_Expr) and then Present (Component_Elmt) loop
2946 Component := Node (Component_Elmt);
2947 Resolve_Aggr_Expr (Positional_Expr, Component);
2949 -- Ada 2005 (AI-231)
2951 if Ada_Version >= Ada_05
2952 and then Nkind (Positional_Expr) = N_Null
2954 Check_Can_Never_Be_Null (Component, Positional_Expr);
2957 if Present (Get_Value (Component, Component_Associations (N))) then
2959 ("more than one value supplied for Component &", N, Component);
2962 Next (Positional_Expr);
2963 Next_Elmt (Component_Elmt);
2966 if Present (Positional_Expr) then
2968 ("too many components for record aggregate", Positional_Expr);
2971 -- Now scan for the named arguments of the aggregate
2973 while Present (Component_Elmt) loop
2974 Component := Node (Component_Elmt);
2975 Expr := Get_Value (Component, Component_Associations (N), True);
2977 -- Note: The previous call to Get_Value sets the value of the
2978 -- variable Is_Box_Present
2980 -- Ada 2005 (AI-287): Handle components with default initialization.
2981 -- Note: This feature was originally added to Ada 2005 for limited
2982 -- but it was finally allowed with any type.
2984 if Is_Box_Present then
2986 Is_Array_Subtype : constant Boolean :=
2987 Ekind (Etype (Component)) =
2993 if Is_Array_Subtype then
2994 Ctyp := Component_Type (Base_Type (Etype (Component)));
2996 Ctyp := Etype (Component);
2999 -- If the component has an initialization procedure (IP) we
3000 -- pass the component to the expander, which will generate
3001 -- the call to such IP.
3003 if Has_Non_Null_Base_Init_Proc (Ctyp)
3004 or else not Expander_Active
3007 (Component => Component,
3009 Is_Box_Present => True);
3011 -- Otherwise we only need to resolve the expression if the
3012 -- component has partially initialized values (required to
3013 -- expand the corresponding assignments and run-time checks).
3015 elsif Present (Expr)
3017 ((not Is_Array_Subtype
3018 and then Is_Partially_Initialized_Type (Component))
3021 and then Is_Partially_Initialized_Type (Ctyp)))
3023 Resolve_Aggr_Expr (Expr, Component);
3027 elsif No (Expr) then
3028 Error_Msg_NE ("no value supplied for component &!", N, Component);
3031 Resolve_Aggr_Expr (Expr, Component);
3034 Next_Elmt (Component_Elmt);
3037 -- STEP 7: check for invalid components + check type in choice list
3044 -- Type of first component in choice list
3047 if Present (Component_Associations (N)) then
3048 Assoc := First (Component_Associations (N));
3053 Verification : while Present (Assoc) loop
3054 Selectr := First (Choices (Assoc));
3057 if Nkind (Selectr) = N_Others_Choice then
3059 -- Ada 2005 (AI-287): others choice may have expression or box
3061 if No (Others_Etype)
3062 and then not Others_Box
3065 ("OTHERS must represent at least one component", Selectr);
3071 while Present (Selectr) loop
3072 New_Assoc := First (New_Assoc_List);
3073 while Present (New_Assoc) loop
3074 Component := First (Choices (New_Assoc));
3075 exit when Chars (Selectr) = Chars (Component);
3079 -- If no association, this is not a legal component of
3080 -- of the type in question, except if its association
3081 -- is provided with a box.
3083 if No (New_Assoc) then
3084 if Box_Present (Parent (Selectr)) then
3086 -- This may still be a bogus component with a box. Scan
3087 -- list of components to verify that a component with
3088 -- that name exists.
3094 C := First_Component (Typ);
3095 while Present (C) loop
3096 if Chars (C) = Chars (Selectr) then
3104 Error_Msg_Node_2 := Typ;
3105 Error_Msg_N ("& is not a component of}", Selectr);
3109 elsif Chars (Selectr) /= Name_uTag
3110 and then Chars (Selectr) /= Name_uParent
3111 and then Chars (Selectr) /= Name_uController
3113 if not Has_Discriminants (Typ) then
3114 Error_Msg_Node_2 := Typ;
3115 Error_Msg_N ("& is not a component of}", Selectr);
3118 ("& is not a component of the aggregate subtype",
3122 Check_Misspelled_Component (Components, Selectr);
3125 elsif No (Typech) then
3126 Typech := Base_Type (Etype (Component));
3128 elsif Typech /= Base_Type (Etype (Component)) then
3129 if not Box_Present (Parent (Selectr)) then
3131 ("components in choice list must have same type",
3140 end loop Verification;
3143 -- STEP 8: replace the original aggregate
3146 New_Aggregate : constant Node_Id := New_Copy (N);
3149 Set_Expressions (New_Aggregate, No_List);
3150 Set_Etype (New_Aggregate, Etype (N));
3151 Set_Component_Associations (New_Aggregate, New_Assoc_List);
3153 Rewrite (N, New_Aggregate);
3155 end Resolve_Record_Aggregate;
3157 -----------------------------
3158 -- Check_Can_Never_Be_Null --
3159 -----------------------------
3161 procedure Check_Can_Never_Be_Null (Typ : Entity_Id; Expr : Node_Id) is
3162 Comp_Typ : Entity_Id;
3166 (Ada_Version >= Ada_05
3167 and then Present (Expr)
3168 and then Nkind (Expr) = N_Null);
3171 when E_Array_Type =>
3172 Comp_Typ := Component_Type (Typ);
3176 Comp_Typ := Etype (Typ);
3182 if Can_Never_Be_Null (Comp_Typ) then
3184 -- Here we know we have a constraint error. Note that we do not use
3185 -- Apply_Compile_Time_Constraint_Error here to the Expr, which might
3186 -- seem the more natural approach. That's because in some cases the
3187 -- components are rewritten, and the replacement would be missed.
3190 (Compile_Time_Constraint_Error
3192 "(Ada 2005) NULL not allowed in null-excluding components?"),
3193 Make_Raise_Constraint_Error (Sloc (Expr),
3194 Reason => CE_Access_Check_Failed));
3196 -- Set proper type for bogus component (why is this needed???)
3198 Set_Etype (Expr, Comp_Typ);
3199 Set_Analyzed (Expr);
3201 end Check_Can_Never_Be_Null;
3203 ---------------------
3204 -- Sort_Case_Table --
3205 ---------------------
3207 procedure Sort_Case_Table (Case_Table : in out Case_Table_Type) is
3208 L : constant Int := Case_Table'First;
3209 U : constant Int := Case_Table'Last;
3217 T := Case_Table (K + 1);
3221 and then Expr_Value (Case_Table (J - 1).Choice_Lo) >
3222 Expr_Value (T.Choice_Lo)
3224 Case_Table (J) := Case_Table (J - 1);
3228 Case_Table (J) := T;
3231 end Sort_Case_Table;
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