1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2004 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, 59 Temple Place - Suite 330, Boston, --
20 -- MA 02111-1307, 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_Util; use Exp_Util;
33 with Freeze; use Freeze;
34 with Itypes; use Itypes;
35 with Lib.Xref; use Lib.Xref;
36 with Namet; use Namet;
37 with Nmake; use Nmake;
38 with Nlists; use Nlists;
41 with Sem_Cat; use Sem_Cat;
42 with Sem_Ch8; use Sem_Ch8;
43 with Sem_Ch13; use Sem_Ch13;
44 with Sem_Eval; use Sem_Eval;
45 with Sem_Res; use Sem_Res;
46 with Sem_Util; use Sem_Util;
47 with Sem_Type; use Sem_Type;
48 with Sem_Warn; use Sem_Warn;
49 with Sinfo; use Sinfo;
50 with Snames; use Snames;
51 with Stringt; use Stringt;
52 with Stand; use Stand;
53 with Targparm; use Targparm;
54 with Tbuild; use Tbuild;
55 with Uintp; use Uintp;
57 with GNAT.Spelling_Checker; use GNAT.Spelling_Checker;
59 package body Sem_Aggr is
61 type Case_Bounds is record
64 Choice_Node : Node_Id;
67 type Case_Table_Type is array (Nat range <>) of Case_Bounds;
68 -- Table type used by Check_Case_Choices procedure
70 -----------------------
71 -- Local Subprograms --
72 -----------------------
74 procedure Sort_Case_Table (Case_Table : in out Case_Table_Type);
75 -- Sort the Case Table using the Lower Bound of each Choice as the key.
76 -- A simple insertion sort is used since the number of choices in a case
77 -- statement of variant part will usually be small and probably in near
80 procedure Check_Can_Never_Be_Null (N : Node_Id; Expr : Node_Id);
81 -- Ada 2005 (AI-231): Check bad usage of the null-exclusion issue
83 ------------------------------------------------------
84 -- Subprograms used for RECORD AGGREGATE Processing --
85 ------------------------------------------------------
87 procedure Resolve_Record_Aggregate (N : Node_Id; Typ : Entity_Id);
88 -- This procedure performs all the semantic checks required for record
89 -- aggregates. Note that for aggregates analysis and resolution go
90 -- hand in hand. Aggregate analysis has been delayed up to here and
91 -- it is done while resolving the aggregate.
93 -- N is the N_Aggregate node.
94 -- Typ is the record type for the aggregate resolution
96 -- While performing the semantic checks, this procedure
97 -- builds a new Component_Association_List where each record field
98 -- appears alone in a Component_Choice_List along with its corresponding
99 -- expression. The record fields in the Component_Association_List
100 -- appear in the same order in which they appear in the record type Typ.
102 -- Once this new Component_Association_List is built and all the
103 -- semantic checks performed, the original aggregate subtree is replaced
104 -- with the new named record aggregate just built. Note that the subtree
105 -- substitution is performed with Rewrite so as to be
106 -- able to retrieve the original aggregate.
108 -- The aggregate subtree manipulation performed by Resolve_Record_Aggregate
109 -- yields the aggregate format expected by Gigi. Typically, this kind of
110 -- tree manipulations are done in the expander. However, because the
111 -- semantic checks that need to be performed on record aggregates really
112 -- go hand in hand with the record aggregate normalization, the aggregate
113 -- subtree transformation is performed during resolution rather than
114 -- expansion. Had we decided otherwise we would have had to duplicate
115 -- most of the code in the expansion procedure Expand_Record_Aggregate.
116 -- Note, however, that all the expansion concerning aggegates for tagged
117 -- records is done in Expand_Record_Aggregate.
119 -- The algorithm of Resolve_Record_Aggregate proceeds as follows:
121 -- 1. Make sure that the record type against which the record aggregate
122 -- has to be resolved is not abstract. Furthermore if the type is
123 -- a null aggregate make sure the input aggregate N is also null.
125 -- 2. Verify that the structure of the aggregate is that of a record
126 -- aggregate. Specifically, look for component associations and ensure
127 -- that each choice list only has identifiers or the N_Others_Choice
128 -- node. Also make sure that if present, the N_Others_Choice occurs
129 -- last and by itself.
131 -- 3. If Typ contains discriminants, the values for each discriminant
132 -- is looked for. If the record type Typ has variants, we check
133 -- that the expressions corresponding to each discriminant ruling
134 -- the (possibly nested) variant parts of Typ, are static. This
135 -- allows us to determine the variant parts to which the rest of
136 -- the aggregate must conform. The names of discriminants with their
137 -- values are saved in a new association list, New_Assoc_List which
138 -- is later augmented with the names and values of the remaining
139 -- components in the record type.
141 -- During this phase we also make sure that every discriminant is
142 -- assigned exactly one value. Note that when several values
143 -- for a given discriminant are found, semantic processing continues
144 -- looking for further errors. In this case it's the first
145 -- discriminant value found which we will be recorded.
147 -- IMPORTANT NOTE: For derived tagged types this procedure expects
148 -- First_Discriminant and Next_Discriminant to give the correct list
149 -- of discriminants, in the correct order.
151 -- 4. After all the discriminant values have been gathered, we can
152 -- set the Etype of the record aggregate. If Typ contains no
153 -- discriminants this is straightforward: the Etype of N is just
154 -- Typ, otherwise a new implicit constrained subtype of Typ is
155 -- built to be the Etype of N.
157 -- 5. Gather the remaining record components according to the discriminant
158 -- values. This involves recursively traversing the record type
159 -- structure to see what variants are selected by the given discriminant
160 -- values. This processing is a little more convoluted if Typ is a
161 -- derived tagged types since we need to retrieve the record structure
162 -- of all the ancestors of Typ.
164 -- 6. After gathering the record components we look for their values
165 -- in the record aggregate and emit appropriate error messages
166 -- should we not find such values or should they be duplicated.
168 -- 7. We then make sure no illegal component names appear in the
169 -- record aggegate and make sure that the type of the record
170 -- components appearing in a same choice list is the same.
171 -- Finally we ensure that the others choice, if present, is
172 -- used to provide the value of at least a record component.
174 -- 8. The original aggregate node is replaced with the new named
175 -- aggregate built in steps 3 through 6, as explained earlier.
177 -- Given the complexity of record aggregate resolution, the primary
178 -- goal of this routine is clarity and simplicity rather than execution
179 -- and storage efficiency. If there are only positional components in the
180 -- aggregate the running time is linear. If there are associations
181 -- the running time is still linear as long as the order of the
182 -- associations is not too far off the order of the components in the
183 -- record type. If this is not the case the running time is at worst
184 -- quadratic in the size of the association list.
186 procedure Check_Misspelled_Component
187 (Elements : Elist_Id;
188 Component : Node_Id);
189 -- Give possible misspelling diagnostic if Component is likely to be
190 -- a misspelling of one of the components of the Assoc_List.
191 -- This is called by Resolv_Aggr_Expr after producing
192 -- an invalid component error message.
194 procedure Check_Static_Discriminated_Subtype (T : Entity_Id; V : Node_Id);
195 -- An optimization: determine whether a discriminated subtype has a
196 -- static constraint, and contains array components whose length is also
197 -- static, either because they are constrained by the discriminant, or
198 -- because the original component bounds are static.
200 -----------------------------------------------------
201 -- Subprograms used for ARRAY AGGREGATE Processing --
202 -----------------------------------------------------
204 function Resolve_Array_Aggregate
207 Index_Constr : Node_Id;
208 Component_Typ : Entity_Id;
209 Others_Allowed : Boolean)
211 -- This procedure performs the semantic checks for an array aggregate.
212 -- True is returned if the aggregate resolution succeeds.
213 -- The procedure works by recursively checking each nested aggregate.
214 -- Specifically, after checking a sub-aggregate nested at the i-th level
215 -- we recursively check all the subaggregates at the i+1-st level (if any).
216 -- Note that for aggregates analysis and resolution go hand in hand.
217 -- Aggregate analysis has been delayed up to here and it is done while
218 -- resolving the aggregate.
220 -- N is the current N_Aggregate node to be checked.
222 -- Index is the index node corresponding to the array sub-aggregate that
223 -- we are currently checking (RM 4.3.3 (8)). Its Etype is the
224 -- corresponding index type (or subtype).
226 -- Index_Constr is the node giving the applicable index constraint if
227 -- any (RM 4.3.3 (10)). It "is a constraint provided by certain
228 -- contexts [...] that can be used to determine the bounds of the array
229 -- value specified by the aggregate". If Others_Allowed below is False
230 -- there is no applicable index constraint and this node is set to Index.
232 -- Component_Typ is the array component type.
234 -- Others_Allowed indicates whether an others choice is allowed
235 -- in the context where the top-level aggregate appeared.
237 -- The algorithm of Resolve_Array_Aggregate proceeds as follows:
239 -- 1. Make sure that the others choice, if present, is by itself and
240 -- appears last in the sub-aggregate. Check that we do not have
241 -- positional and named components in the array sub-aggregate (unless
242 -- the named association is an others choice). Finally if an others
243 -- choice is present, make sure it is allowed in the aggregate contex.
245 -- 2. If the array sub-aggregate contains discrete_choices:
247 -- (A) Verify their validity. Specifically verify that:
249 -- (a) If a null range is present it must be the only possible
250 -- choice in the array aggregate.
252 -- (b) Ditto for a non static range.
254 -- (c) Ditto for a non static expression.
256 -- In addition this step analyzes and resolves each discrete_choice,
257 -- making sure that its type is the type of the corresponding Index.
258 -- If we are not at the lowest array aggregate level (in the case of
259 -- multi-dimensional aggregates) then invoke Resolve_Array_Aggregate
260 -- recursively on each component expression. Otherwise, resolve the
261 -- bottom level component expressions against the expected component
262 -- type ONLY IF the component corresponds to a single discrete choice
263 -- which is not an others choice (to see why read the DELAYED
264 -- COMPONENT RESOLUTION below).
266 -- (B) Determine the bounds of the sub-aggregate and lowest and
267 -- highest choice values.
269 -- 3. For positional aggregates:
271 -- (A) Loop over the component expressions either recursively invoking
272 -- Resolve_Array_Aggregate on each of these for multi-dimensional
273 -- array aggregates or resolving the bottom level component
274 -- expressions against the expected component type.
276 -- (B) Determine the bounds of the positional sub-aggregates.
278 -- 4. Try to determine statically whether the evaluation of the array
279 -- sub-aggregate raises Constraint_Error. If yes emit proper
280 -- warnings. The precise checks are the following:
282 -- (A) Check that the index range defined by aggregate bounds is
283 -- compatible with corresponding index subtype.
284 -- We also check against the base type. In fact it could be that
285 -- Low/High bounds of the base type are static whereas those of
286 -- the index subtype are not. Thus if we can statically catch
287 -- a problem with respect to the base type we are guaranteed
288 -- that the same problem will arise with the index subtype
290 -- (B) If we are dealing with a named aggregate containing an others
291 -- choice and at least one discrete choice then make sure the range
292 -- specified by the discrete choices does not overflow the
293 -- aggregate bounds. We also check against the index type and base
294 -- type bounds for the same reasons given in (A).
296 -- (C) If we are dealing with a positional aggregate with an others
297 -- choice make sure the number of positional elements specified
298 -- does not overflow the aggregate bounds. We also check against
299 -- the index type and base type bounds as mentioned in (A).
301 -- Finally construct an N_Range node giving the sub-aggregate bounds.
302 -- Set the Aggregate_Bounds field of the sub-aggregate to be this
303 -- N_Range. The routine Array_Aggr_Subtype below uses such N_Ranges
304 -- to build the appropriate aggregate subtype. Aggregate_Bounds
305 -- information is needed during expansion.
307 -- DELAYED COMPONENT RESOLUTION: The resolution of bottom level component
308 -- expressions in an array aggregate may call Duplicate_Subexpr or some
309 -- other routine that inserts code just outside the outermost aggregate.
310 -- If the array aggregate contains discrete choices or an others choice,
311 -- this may be wrong. Consider for instance the following example.
313 -- type Rec is record
317 -- type Acc_Rec is access Rec;
318 -- Arr : array (1..3) of Acc_Rec := (1 .. 3 => new Rec);
320 -- Then the transformation of "new Rec" that occurs during resolution
321 -- entails the following code modifications
323 -- P7b : constant Acc_Rec := new Rec;
325 -- Arr : array (1..3) of Acc_Rec := (1 .. 3 => P7b);
327 -- This code transformation is clearly wrong, since we need to call
328 -- "new Rec" for each of the 3 array elements. To avoid this problem we
329 -- delay resolution of the components of non positional array aggregates
330 -- to the expansion phase. As an optimization, if the discrete choice
331 -- specifies a single value we do not delay resolution.
333 function Array_Aggr_Subtype (N : Node_Id; Typ : Node_Id) return Entity_Id;
334 -- This routine returns the type or subtype of an array aggregate.
336 -- N is the array aggregate node whose type we return.
338 -- Typ is the context type in which N occurs.
340 -- This routine creates an implicit array subtype whose bounds are
341 -- those defined by the aggregate. When this routine is invoked
342 -- Resolve_Array_Aggregate has already processed aggregate N. Thus the
343 -- Aggregate_Bounds of each sub-aggregate, is an N_Range node giving the
344 -- sub-aggregate bounds. When building the aggegate itype, this function
345 -- traverses the array aggregate N collecting such Aggregate_Bounds and
346 -- constructs the proper array aggregate itype.
348 -- Note that in the case of multidimensional aggregates each inner
349 -- sub-aggregate corresponding to a given array dimension, may provide a
350 -- different bounds. If it is possible to determine statically that
351 -- some sub-aggregates corresponding to the same index do not have the
352 -- same bounds, then a warning is emitted. If such check is not possible
353 -- statically (because some sub-aggregate bounds are dynamic expressions)
354 -- then this job is left to the expander. In all cases the particular
355 -- bounds that this function will chose for a given dimension is the first
356 -- N_Range node for a sub-aggregate corresponding to that dimension.
358 -- Note that the Raises_Constraint_Error flag of an array aggregate
359 -- whose evaluation is determined to raise CE by Resolve_Array_Aggregate,
360 -- is set in Resolve_Array_Aggregate but the aggregate is not
361 -- immediately replaced with a raise CE. In fact, Array_Aggr_Subtype must
362 -- first construct the proper itype for the aggregate (Gigi needs
363 -- this). After constructing the proper itype we will eventually replace
364 -- the top-level aggregate with a raise CE (done in Resolve_Aggregate).
365 -- Of course in cases such as:
367 -- type Arr is array (integer range <>) of Integer;
368 -- A : Arr := (positive range -1 .. 2 => 0);
370 -- The bounds of the aggregate itype are cooked up to look reasonable
371 -- (in this particular case the bounds will be 1 .. 2).
373 procedure Aggregate_Constraint_Checks
375 Check_Typ : Entity_Id);
376 -- Checks expression Exp against subtype Check_Typ. If Exp is an
377 -- aggregate and Check_Typ a constrained record type with discriminants,
378 -- we generate the appropriate discriminant checks. If Exp is an array
379 -- aggregate then emit the appropriate length checks. If Exp is a scalar
380 -- type, or a string literal, Exp is changed into Check_Typ'(Exp) to
381 -- ensure that range checks are performed at run time.
383 procedure Make_String_Into_Aggregate (N : Node_Id);
384 -- A string literal can appear in a context in which a one dimensional
385 -- array of characters is expected. This procedure simply rewrites the
386 -- string as an aggregate, prior to resolution.
388 ---------------------------------
389 -- Aggregate_Constraint_Checks --
390 ---------------------------------
392 procedure Aggregate_Constraint_Checks
394 Check_Typ : Entity_Id)
396 Exp_Typ : constant Entity_Id := Etype (Exp);
399 if Raises_Constraint_Error (Exp) then
403 -- This is really expansion activity, so make sure that expansion
404 -- is on and is allowed.
406 if not Expander_Active or else In_Default_Expression then
410 -- First check if we have to insert discriminant checks
412 if Has_Discriminants (Exp_Typ) then
413 Apply_Discriminant_Check (Exp, Check_Typ);
415 -- Next emit length checks for array aggregates
417 elsif Is_Array_Type (Exp_Typ) then
418 Apply_Length_Check (Exp, Check_Typ);
420 -- Finally emit scalar and string checks. If we are dealing with a
421 -- scalar literal we need to check by hand because the Etype of
422 -- literals is not necessarily correct.
424 elsif Is_Scalar_Type (Exp_Typ)
425 and then Compile_Time_Known_Value (Exp)
427 if Is_Out_Of_Range (Exp, Base_Type (Check_Typ)) then
428 Apply_Compile_Time_Constraint_Error
429 (Exp, "value not in range of}?", CE_Range_Check_Failed,
430 Ent => Base_Type (Check_Typ),
431 Typ => Base_Type (Check_Typ));
433 elsif Is_Out_Of_Range (Exp, Check_Typ) then
434 Apply_Compile_Time_Constraint_Error
435 (Exp, "value not in range of}?", CE_Range_Check_Failed,
439 elsif not Range_Checks_Suppressed (Check_Typ) then
440 Apply_Scalar_Range_Check (Exp, Check_Typ);
443 elsif (Is_Scalar_Type (Exp_Typ)
444 or else Nkind (Exp) = N_String_Literal)
445 and then Exp_Typ /= Check_Typ
447 if Is_Entity_Name (Exp)
448 and then Ekind (Entity (Exp)) = E_Constant
450 -- If expression is a constant, it is worthwhile checking whether
451 -- it is a bound of the type.
453 if (Is_Entity_Name (Type_Low_Bound (Check_Typ))
454 and then Entity (Exp) = Entity (Type_Low_Bound (Check_Typ)))
455 or else (Is_Entity_Name (Type_High_Bound (Check_Typ))
456 and then Entity (Exp) = Entity (Type_High_Bound (Check_Typ)))
461 Rewrite (Exp, Convert_To (Check_Typ, Relocate_Node (Exp)));
462 Analyze_And_Resolve (Exp, Check_Typ);
463 Check_Unset_Reference (Exp);
466 Rewrite (Exp, Convert_To (Check_Typ, Relocate_Node (Exp)));
467 Analyze_And_Resolve (Exp, Check_Typ);
468 Check_Unset_Reference (Exp);
471 -- Ada 2005 (AI-231): Generate conversion to the null-excluding
472 -- type to force the corresponding run-time check
474 elsif Is_Access_Type (Check_Typ)
475 and then Can_Never_Be_Null (Check_Typ)
476 and then not Can_Never_Be_Null (Exp_Typ)
478 Rewrite (Exp, Convert_To (Check_Typ, Relocate_Node (Exp)));
479 Analyze_And_Resolve (Exp, Check_Typ);
480 Check_Unset_Reference (Exp);
482 end Aggregate_Constraint_Checks;
484 ------------------------
485 -- Array_Aggr_Subtype --
486 ------------------------
488 function Array_Aggr_Subtype
493 Aggr_Dimension : constant Pos := Number_Dimensions (Typ);
494 -- Number of aggregate index dimensions.
496 Aggr_Range : array (1 .. Aggr_Dimension) of Node_Id := (others => Empty);
497 -- Constrained N_Range of each index dimension in our aggregate itype.
499 Aggr_Low : array (1 .. Aggr_Dimension) of Node_Id := (others => Empty);
500 Aggr_High : array (1 .. Aggr_Dimension) of Node_Id := (others => Empty);
501 -- Low and High bounds for each index dimension in our aggregate itype.
503 Is_Fully_Positional : Boolean := True;
505 procedure Collect_Aggr_Bounds (N : Node_Id; Dim : Pos);
506 -- N is an array (sub-)aggregate. Dim is the dimension corresponding to
507 -- (sub-)aggregate N. This procedure collects the constrained N_Range
508 -- nodes corresponding to each index dimension of our aggregate itype.
509 -- These N_Range nodes are collected in Aggr_Range above.
510 -- Likewise collect in Aggr_Low & Aggr_High above the low and high
511 -- bounds of each index dimension. If, when collecting, two bounds
512 -- corresponding to the same dimension are static and found to differ,
513 -- then emit a warning, and mark N as raising Constraint_Error.
515 -------------------------
516 -- Collect_Aggr_Bounds --
517 -------------------------
519 procedure Collect_Aggr_Bounds (N : Node_Id; Dim : Pos) is
520 This_Range : constant Node_Id := Aggregate_Bounds (N);
521 -- The aggregate range node of this specific sub-aggregate.
523 This_Low : constant Node_Id := Low_Bound (Aggregate_Bounds (N));
524 This_High : constant Node_Id := High_Bound (Aggregate_Bounds (N));
525 -- The aggregate bounds of this specific sub-aggregate.
531 -- Collect the first N_Range for a given dimension that you find.
532 -- For a given dimension they must be all equal anyway.
534 if No (Aggr_Range (Dim)) then
535 Aggr_Low (Dim) := This_Low;
536 Aggr_High (Dim) := This_High;
537 Aggr_Range (Dim) := This_Range;
540 if Compile_Time_Known_Value (This_Low) then
541 if not Compile_Time_Known_Value (Aggr_Low (Dim)) then
542 Aggr_Low (Dim) := This_Low;
544 elsif Expr_Value (This_Low) /= Expr_Value (Aggr_Low (Dim)) then
545 Set_Raises_Constraint_Error (N);
546 Error_Msg_N ("Sub-aggregate low bound mismatch?", N);
547 Error_Msg_N ("Constraint_Error will be raised at run-time?",
552 if Compile_Time_Known_Value (This_High) then
553 if not Compile_Time_Known_Value (Aggr_High (Dim)) then
554 Aggr_High (Dim) := This_High;
557 Expr_Value (This_High) /= Expr_Value (Aggr_High (Dim))
559 Set_Raises_Constraint_Error (N);
560 Error_Msg_N ("Sub-aggregate high bound mismatch?", N);
561 Error_Msg_N ("Constraint_Error will be raised at run-time?",
567 if Dim < Aggr_Dimension then
569 -- Process positional components
571 if Present (Expressions (N)) then
572 Expr := First (Expressions (N));
573 while Present (Expr) loop
574 Collect_Aggr_Bounds (Expr, Dim + 1);
579 -- Process component associations
581 if Present (Component_Associations (N)) then
582 Is_Fully_Positional := False;
584 Assoc := First (Component_Associations (N));
585 while Present (Assoc) loop
586 Expr := Expression (Assoc);
587 Collect_Aggr_Bounds (Expr, Dim + 1);
592 end Collect_Aggr_Bounds;
594 -- Array_Aggr_Subtype variables
597 -- the final itype of the overall aggregate
599 Index_Constraints : constant List_Id := New_List;
600 -- The list of index constraints of the aggregate itype.
602 -- Start of processing for Array_Aggr_Subtype
605 -- Make sure that the list of index constraints is properly attached
606 -- to the tree, and then collect the aggregate bounds.
608 Set_Parent (Index_Constraints, N);
609 Collect_Aggr_Bounds (N, 1);
611 -- Build the list of constrained indices of our aggregate itype.
613 for J in 1 .. Aggr_Dimension loop
614 Create_Index : declare
615 Index_Base : constant Entity_Id :=
616 Base_Type (Etype (Aggr_Range (J)));
617 Index_Typ : Entity_Id;
620 -- Construct the Index subtype
622 Index_Typ := Create_Itype (Subtype_Kind (Ekind (Index_Base)), N);
624 Set_Etype (Index_Typ, Index_Base);
626 if Is_Character_Type (Index_Base) then
627 Set_Is_Character_Type (Index_Typ);
630 Set_Size_Info (Index_Typ, (Index_Base));
631 Set_RM_Size (Index_Typ, RM_Size (Index_Base));
632 Set_First_Rep_Item (Index_Typ, First_Rep_Item (Index_Base));
633 Set_Scalar_Range (Index_Typ, Aggr_Range (J));
635 if Is_Discrete_Or_Fixed_Point_Type (Index_Typ) then
636 Set_RM_Size (Index_Typ, UI_From_Int (Minimum_Size (Index_Typ)));
639 Set_Etype (Aggr_Range (J), Index_Typ);
641 Append (Aggr_Range (J), To => Index_Constraints);
645 -- Now build the Itype
647 Itype := Create_Itype (E_Array_Subtype, N);
649 Set_First_Rep_Item (Itype, First_Rep_Item (Typ));
650 Set_Convention (Itype, Convention (Typ));
651 Set_Depends_On_Private (Itype, Has_Private_Component (Typ));
652 Set_Etype (Itype, Base_Type (Typ));
653 Set_Has_Alignment_Clause (Itype, Has_Alignment_Clause (Typ));
654 Set_Is_Aliased (Itype, Is_Aliased (Typ));
655 Set_Depends_On_Private (Itype, Depends_On_Private (Typ));
657 Copy_Suppress_Status (Index_Check, Typ, Itype);
658 Copy_Suppress_Status (Length_Check, Typ, Itype);
660 Set_First_Index (Itype, First (Index_Constraints));
661 Set_Is_Constrained (Itype, True);
662 Set_Is_Internal (Itype, True);
663 Init_Size_Align (Itype);
665 -- A simple optimization: purely positional aggregates of static
666 -- components should be passed to gigi unexpanded whenever possible,
667 -- and regardless of the staticness of the bounds themselves. Subse-
668 -- quent checks in exp_aggr verify that type is not packed, etc.
670 Set_Size_Known_At_Compile_Time (Itype,
672 and then Comes_From_Source (N)
673 and then Size_Known_At_Compile_Time (Component_Type (Typ)));
675 -- We always need a freeze node for a packed array subtype, so that
676 -- we can build the Packed_Array_Type corresponding to the subtype.
677 -- If expansion is disabled, the packed array subtype is not built,
678 -- and we must not generate a freeze node for the type, or else it
679 -- will appear incomplete to gigi.
681 if Is_Packed (Itype) and then not In_Default_Expression
682 and then Expander_Active
684 Freeze_Itype (Itype, N);
688 end Array_Aggr_Subtype;
690 --------------------------------
691 -- Check_Misspelled_Component --
692 --------------------------------
694 procedure Check_Misspelled_Component
695 (Elements : Elist_Id;
698 Max_Suggestions : constant := 2;
700 Nr_Of_Suggestions : Natural := 0;
701 Suggestion_1 : Entity_Id := Empty;
702 Suggestion_2 : Entity_Id := Empty;
703 Component_Elmt : Elmt_Id;
706 -- All the components of List are matched against Component and
707 -- a count is maintained of possible misspellings. When at the
708 -- end of the analysis there are one or two (not more!) possible
709 -- misspellings, these misspellings will be suggested as
710 -- possible correction.
712 Get_Name_String (Chars (Component));
715 S : constant String (1 .. Name_Len) :=
716 Name_Buffer (1 .. Name_Len);
720 Component_Elmt := First_Elmt (Elements);
722 while Nr_Of_Suggestions <= Max_Suggestions
723 and then Present (Component_Elmt)
726 Get_Name_String (Chars (Node (Component_Elmt)));
728 if Is_Bad_Spelling_Of (Name_Buffer (1 .. Name_Len), S) then
729 Nr_Of_Suggestions := Nr_Of_Suggestions + 1;
731 case Nr_Of_Suggestions is
732 when 1 => Suggestion_1 := Node (Component_Elmt);
733 when 2 => Suggestion_2 := Node (Component_Elmt);
738 Next_Elmt (Component_Elmt);
741 -- Report at most two suggestions
743 if Nr_Of_Suggestions = 1 then
744 Error_Msg_NE ("\possible misspelling of&",
745 Component, Suggestion_1);
747 elsif Nr_Of_Suggestions = 2 then
748 Error_Msg_Node_2 := Suggestion_2;
749 Error_Msg_NE ("\possible misspelling of& or&",
750 Component, Suggestion_1);
753 end Check_Misspelled_Component;
755 ----------------------------------------
756 -- Check_Static_Discriminated_Subtype --
757 ----------------------------------------
759 procedure Check_Static_Discriminated_Subtype (T : Entity_Id; V : Node_Id) is
760 Disc : constant Entity_Id := First_Discriminant (T);
765 if Has_Record_Rep_Clause (T) then
768 elsif Present (Next_Discriminant (Disc)) then
771 elsif Nkind (V) /= N_Integer_Literal then
775 Comp := First_Component (T);
777 while Present (Comp) loop
779 if Is_Scalar_Type (Etype (Comp)) then
782 elsif Is_Private_Type (Etype (Comp))
783 and then Present (Full_View (Etype (Comp)))
784 and then Is_Scalar_Type (Full_View (Etype (Comp)))
788 elsif Is_Array_Type (Etype (Comp)) then
790 if Is_Bit_Packed_Array (Etype (Comp)) then
794 Ind := First_Index (Etype (Comp));
796 while Present (Ind) loop
798 if Nkind (Ind) /= N_Range
799 or else Nkind (Low_Bound (Ind)) /= N_Integer_Literal
800 or else Nkind (High_Bound (Ind)) /= N_Integer_Literal
812 Next_Component (Comp);
815 -- On exit, all components have statically known sizes.
817 Set_Size_Known_At_Compile_Time (T);
818 end Check_Static_Discriminated_Subtype;
820 --------------------------------
821 -- Make_String_Into_Aggregate --
822 --------------------------------
824 procedure Make_String_Into_Aggregate (N : Node_Id) is
825 Exprs : constant List_Id := New_List;
826 Loc : constant Source_Ptr := Sloc (N);
827 Str : constant String_Id := Strval (N);
828 Strlen : constant Nat := String_Length (Str);
836 for J in 1 .. Strlen loop
837 C := Get_String_Char (Str, J);
838 Set_Character_Literal_Name (C);
840 C_Node := Make_Character_Literal (P, Name_Find, C);
841 Set_Etype (C_Node, Any_Character);
842 Append_To (Exprs, C_Node);
845 -- something special for wide strings ???
848 New_N := Make_Aggregate (Loc, Expressions => Exprs);
849 Set_Analyzed (New_N);
850 Set_Etype (New_N, Any_Composite);
853 end Make_String_Into_Aggregate;
855 -----------------------
856 -- Resolve_Aggregate --
857 -----------------------
859 procedure Resolve_Aggregate (N : Node_Id; Typ : Entity_Id) is
860 Pkind : constant Node_Kind := Nkind (Parent (N));
862 Aggr_Subtyp : Entity_Id;
863 -- The actual aggregate subtype. This is not necessarily the same as Typ
864 -- which is the subtype of the context in which the aggregate was found.
867 -- Check for aggregates not allowed in configurable run-time mode.
868 -- We allow all cases of aggregates that do not come from source,
869 -- since these are all assumed to be small (e.g. bounds of a string
870 -- literal). We also allow aggregates of types we know to be small.
872 if not Support_Aggregates_On_Target
873 and then Comes_From_Source (N)
874 and then (not Known_Static_Esize (Typ) or else Esize (Typ) > 64)
876 Error_Msg_CRT ("aggregate", N);
879 if Is_Limited_Composite (Typ) then
880 Error_Msg_N ("aggregate type cannot have limited component", N);
881 Explain_Limited_Type (Typ, N);
883 -- Ada 2005 (AI-287): Limited aggregates allowed
885 elsif Is_Limited_Type (Typ)
886 and Ada_Version < Ada_05
888 Error_Msg_N ("aggregate type cannot be limited", N);
889 Explain_Limited_Type (Typ, N);
891 elsif Is_Class_Wide_Type (Typ) then
892 Error_Msg_N ("type of aggregate cannot be class-wide", N);
894 elsif Typ = Any_String
895 or else Typ = Any_Composite
897 Error_Msg_N ("no unique type for aggregate", N);
898 Set_Etype (N, Any_Composite);
900 elsif Is_Array_Type (Typ) and then Null_Record_Present (N) then
901 Error_Msg_N ("null record forbidden in array aggregate", N);
903 elsif Is_Record_Type (Typ) then
904 Resolve_Record_Aggregate (N, Typ);
906 elsif Is_Array_Type (Typ) then
908 -- First a special test, for the case of a positional aggregate
909 -- of characters which can be replaced by a string literal.
910 -- Do not perform this transformation if this was a string literal
911 -- to start with, whose components needed constraint checks, or if
912 -- the component type is non-static, because it will require those
913 -- checks and be transformed back into an aggregate.
915 if Number_Dimensions (Typ) = 1
917 (Root_Type (Component_Type (Typ)) = Standard_Character
919 Root_Type (Component_Type (Typ)) = Standard_Wide_Character)
920 and then No (Component_Associations (N))
921 and then not Is_Limited_Composite (Typ)
922 and then not Is_Private_Composite (Typ)
923 and then not Is_Bit_Packed_Array (Typ)
924 and then Nkind (Original_Node (Parent (N))) /= N_String_Literal
925 and then Is_Static_Subtype (Component_Type (Typ))
931 Expr := First (Expressions (N));
932 while Present (Expr) loop
933 exit when Nkind (Expr) /= N_Character_Literal;
940 Expr := First (Expressions (N));
941 while Present (Expr) loop
942 Store_String_Char (Char_Literal_Value (Expr));
947 Make_String_Literal (Sloc (N), End_String));
949 Analyze_And_Resolve (N, Typ);
955 -- Here if we have a real aggregate to deal with
957 Array_Aggregate : declare
958 Aggr_Resolved : Boolean;
960 Aggr_Typ : constant Entity_Id := Etype (Typ);
961 -- This is the unconstrained array type, which is the type
962 -- against which the aggregate is to be resolved. Typ itself
963 -- is the array type of the context which may not be the same
964 -- subtype as the subtype for the final aggregate.
967 -- In the following we determine whether an others choice is
968 -- allowed inside the array aggregate. The test checks the context
969 -- in which the array aggregate occurs. If the context does not
970 -- permit it, or the aggregate type is unconstrained, an others
971 -- choice is not allowed.
973 -- Note that there is no node for Explicit_Actual_Parameter.
974 -- To test for this context we therefore have to test for node
975 -- N_Parameter_Association which itself appears only if there is a
976 -- formal parameter. Consequently we also need to test for
977 -- N_Procedure_Call_Statement or N_Function_Call.
979 Set_Etype (N, Aggr_Typ); -- may be overridden later on
981 -- Ada 2005 (AI-231): Propagate the null_exclusion attribute to
982 -- the components of the array aggregate
984 if Ada_Version >= Ada_05 then
985 Set_Can_Never_Be_Null (Aggr_Typ, Can_Never_Be_Null (Typ));
988 if Is_Constrained (Typ) and then
989 (Pkind = N_Assignment_Statement or else
990 Pkind = N_Parameter_Association or else
991 Pkind = N_Function_Call or else
992 Pkind = N_Procedure_Call_Statement or else
993 Pkind = N_Generic_Association or else
994 Pkind = N_Formal_Object_Declaration or else
995 Pkind = N_Return_Statement or else
996 Pkind = N_Object_Declaration or else
997 Pkind = N_Component_Declaration or else
998 Pkind = N_Parameter_Specification or else
999 Pkind = N_Qualified_Expression or else
1000 Pkind = N_Aggregate or else
1001 Pkind = N_Extension_Aggregate or else
1002 Pkind = N_Component_Association)
1005 Resolve_Array_Aggregate
1007 Index => First_Index (Aggr_Typ),
1008 Index_Constr => First_Index (Typ),
1009 Component_Typ => Component_Type (Typ),
1010 Others_Allowed => True);
1014 Resolve_Array_Aggregate
1016 Index => First_Index (Aggr_Typ),
1017 Index_Constr => First_Index (Aggr_Typ),
1018 Component_Typ => Component_Type (Typ),
1019 Others_Allowed => False);
1022 if not Aggr_Resolved then
1023 Aggr_Subtyp := Any_Composite;
1025 Aggr_Subtyp := Array_Aggr_Subtype (N, Typ);
1028 Set_Etype (N, Aggr_Subtyp);
1029 end Array_Aggregate;
1032 Error_Msg_N ("illegal context for aggregate", N);
1036 -- If we can determine statically that the evaluation of the
1037 -- aggregate raises Constraint_Error, then replace the
1038 -- aggregate with an N_Raise_Constraint_Error node, but set the
1039 -- Etype to the right aggregate subtype. Gigi needs this.
1041 if Raises_Constraint_Error (N) then
1042 Aggr_Subtyp := Etype (N);
1044 Make_Raise_Constraint_Error (Sloc (N),
1045 Reason => CE_Range_Check_Failed));
1046 Set_Raises_Constraint_Error (N);
1047 Set_Etype (N, Aggr_Subtyp);
1050 end Resolve_Aggregate;
1052 -----------------------------
1053 -- Resolve_Array_Aggregate --
1054 -----------------------------
1056 function Resolve_Array_Aggregate
1059 Index_Constr : Node_Id;
1060 Component_Typ : Entity_Id;
1061 Others_Allowed : Boolean)
1064 Loc : constant Source_Ptr := Sloc (N);
1066 Failure : constant Boolean := False;
1067 Success : constant Boolean := True;
1069 Index_Typ : constant Entity_Id := Etype (Index);
1070 Index_Typ_Low : constant Node_Id := Type_Low_Bound (Index_Typ);
1071 Index_Typ_High : constant Node_Id := Type_High_Bound (Index_Typ);
1072 -- The type of the index corresponding to the array sub-aggregate
1073 -- along with its low and upper bounds
1075 Index_Base : constant Entity_Id := Base_Type (Index_Typ);
1076 Index_Base_Low : constant Node_Id := Type_Low_Bound (Index_Base);
1077 Index_Base_High : constant Node_Id := Type_High_Bound (Index_Base);
1078 -- ditto for the base type
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 <= BH
1087 -- (the upper bound of the index base type). If the check fails a
1088 -- warning is emitted, the Raises_Constraint_Error Flag of N is set,
1089 -- 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)
1111 -- Resolves aggregate expression Expr. Returs False if resolution
1112 -- fails. If Single_Elmt is set to False, the expression Expr may be
1113 -- used to initialize several array aggregate elements (this can
1114 -- happen for discrete choices such as "L .. H => Expr" or the others
1115 -- choice). In this event we do not resolve Expr unless expansion is
1116 -- disabled. To know why, see the DELAYED COMPONENT RESOLUTION
1123 function Add (Val : Uint; To : Node_Id) return Node_Id is
1129 if Raises_Constraint_Error (To) then
1133 -- First test if we can do constant folding
1135 if Compile_Time_Known_Value (To)
1136 or else Nkind (To) = N_Integer_Literal
1138 Expr_Pos := Make_Integer_Literal (Loc, Expr_Value (To) + Val);
1139 Set_Is_Static_Expression (Expr_Pos);
1140 Set_Etype (Expr_Pos, Etype (To));
1141 Set_Analyzed (Expr_Pos, Analyzed (To));
1143 if not Is_Enumeration_Type (Index_Typ) then
1146 -- If we are dealing with enumeration return
1147 -- Index_Typ'Val (Expr_Pos)
1151 Make_Attribute_Reference
1153 Prefix => New_Reference_To (Index_Typ, Loc),
1154 Attribute_Name => Name_Val,
1155 Expressions => New_List (Expr_Pos));
1161 -- If we are here no constant folding possible
1163 if not Is_Enumeration_Type (Index_Base) then
1166 Left_Opnd => Duplicate_Subexpr (To),
1167 Right_Opnd => Make_Integer_Literal (Loc, Val));
1169 -- If we are dealing with enumeration return
1170 -- Index_Typ'Val (Index_Typ'Pos (To) + Val)
1174 Make_Attribute_Reference
1176 Prefix => New_Reference_To (Index_Typ, Loc),
1177 Attribute_Name => Name_Pos,
1178 Expressions => New_List (Duplicate_Subexpr (To)));
1182 Left_Opnd => To_Pos,
1183 Right_Opnd => Make_Integer_Literal (Loc, Val));
1186 Make_Attribute_Reference
1188 Prefix => New_Reference_To (Index_Typ, Loc),
1189 Attribute_Name => Name_Val,
1190 Expressions => New_List (Expr_Pos));
1200 procedure Check_Bound (BH : Node_Id; AH : in out Node_Id) is
1208 Get (Value => Val_BH, From => BH, OK => OK_BH);
1209 Get (Value => Val_AH, From => AH, OK => OK_AH);
1211 if OK_BH and then OK_AH and then Val_BH < Val_AH then
1212 Set_Raises_Constraint_Error (N);
1213 Error_Msg_N ("upper bound out of range?", AH);
1214 Error_Msg_N ("Constraint_Error will be raised at run-time?", AH);
1216 -- You need to set AH to BH or else in the case of enumerations
1217 -- indices we will not be able to resolve the aggregate bounds.
1219 AH := Duplicate_Subexpr (BH);
1227 procedure Check_Bounds (L, H : Node_Id; AL, AH : Node_Id) is
1239 if Raises_Constraint_Error (N)
1240 or else Dynamic_Or_Null_Range (AL, AH)
1245 Get (Value => Val_L, From => L, OK => OK_L);
1246 Get (Value => Val_H, From => H, OK => OK_H);
1248 Get (Value => Val_AL, From => AL, OK => OK_AL);
1249 Get (Value => Val_AH, From => AH, OK => OK_AH);
1251 if OK_L and then Val_L > Val_AL then
1252 Set_Raises_Constraint_Error (N);
1253 Error_Msg_N ("lower bound of aggregate out of range?", N);
1254 Error_Msg_N ("\Constraint_Error will be raised at run-time?", N);
1257 if OK_H and then Val_H < Val_AH then
1258 Set_Raises_Constraint_Error (N);
1259 Error_Msg_N ("upper bound of aggregate out of range?", N);
1260 Error_Msg_N ("\Constraint_Error will be raised at run-time?", N);
1268 procedure Check_Length (L, H : Node_Id; Len : Uint) is
1278 if Raises_Constraint_Error (N) then
1282 Get (Value => Val_L, From => L, OK => OK_L);
1283 Get (Value => Val_H, From => H, OK => OK_H);
1285 if not OK_L or else not OK_H then
1289 -- If null range length is zero
1291 if Val_L > Val_H then
1292 Range_Len := Uint_0;
1294 Range_Len := Val_H - Val_L + 1;
1297 if Range_Len < Len then
1298 Set_Raises_Constraint_Error (N);
1299 Error_Msg_N ("Too many elements?", N);
1300 Error_Msg_N ("Constraint_Error will be raised at run-time?", N);
1304 ---------------------------
1305 -- Dynamic_Or_Null_Range --
1306 ---------------------------
1308 function Dynamic_Or_Null_Range (L, H : Node_Id) return Boolean is
1316 Get (Value => Val_L, From => L, OK => OK_L);
1317 Get (Value => Val_H, From => H, OK => OK_H);
1319 return not OK_L or else not OK_H
1320 or else not Is_OK_Static_Expression (L)
1321 or else not Is_OK_Static_Expression (H)
1322 or else Val_L > Val_H;
1323 end Dynamic_Or_Null_Range;
1329 procedure Get (Value : out Uint; From : Node_Id; OK : out Boolean) is
1333 if Compile_Time_Known_Value (From) then
1334 Value := Expr_Value (From);
1336 -- If expression From is something like Some_Type'Val (10) then
1339 elsif Nkind (From) = N_Attribute_Reference
1340 and then Attribute_Name (From) = Name_Val
1341 and then Compile_Time_Known_Value (First (Expressions (From)))
1343 Value := Expr_Value (First (Expressions (From)));
1351 -----------------------
1352 -- Resolve_Aggr_Expr --
1353 -----------------------
1355 function Resolve_Aggr_Expr
1357 Single_Elmt : Boolean)
1360 Nxt_Ind : constant Node_Id := Next_Index (Index);
1361 Nxt_Ind_Constr : constant Node_Id := Next_Index (Index_Constr);
1362 -- Index is the current index corresponding to the expresion.
1364 Resolution_OK : Boolean := True;
1365 -- Set to False if resolution of the expression failed.
1368 -- If the array type against which we are resolving the aggregate
1369 -- has several dimensions, the expressions nested inside the
1370 -- aggregate must be further aggregates (or strings).
1372 if Present (Nxt_Ind) then
1373 if Nkind (Expr) /= N_Aggregate then
1375 -- A string literal can appear where a one-dimensional array
1376 -- of characters is expected. If the literal looks like an
1377 -- operator, it is still an operator symbol, which will be
1378 -- transformed into a string when analyzed.
1380 if Is_Character_Type (Component_Typ)
1381 and then No (Next_Index (Nxt_Ind))
1382 and then (Nkind (Expr) = N_String_Literal
1383 or else Nkind (Expr) = N_Operator_Symbol)
1385 -- A string literal used in a multidimensional array
1386 -- aggregate in place of the final one-dimensional
1387 -- aggregate must not be enclosed in parentheses.
1389 if Paren_Count (Expr) /= 0 then
1390 Error_Msg_N ("No parenthesis allowed here", Expr);
1393 Make_String_Into_Aggregate (Expr);
1396 Error_Msg_N ("nested array aggregate expected", Expr);
1401 -- Ada 2005 (AI-231): Propagate the type to the nested aggregate.
1402 -- Required to check the null-exclusion attribute (if present).
1403 -- This value may be overridden later on.
1405 Set_Etype (Expr, Etype (N));
1407 Resolution_OK := Resolve_Array_Aggregate
1408 (Expr, Nxt_Ind, Nxt_Ind_Constr, Component_Typ, Others_Allowed);
1410 -- Do not resolve the expressions of discrete or others choices
1411 -- unless the expression covers a single component, or the expander
1415 or else not Expander_Active
1416 or else In_Default_Expression
1418 Analyze_And_Resolve (Expr, Component_Typ);
1419 Check_Non_Static_Context (Expr);
1420 Aggregate_Constraint_Checks (Expr, Component_Typ);
1421 Check_Unset_Reference (Expr);
1424 if Raises_Constraint_Error (Expr)
1425 and then Nkind (Parent (Expr)) /= N_Component_Association
1427 Set_Raises_Constraint_Error (N);
1430 return Resolution_OK;
1431 end Resolve_Aggr_Expr;
1433 -- Variables local to Resolve_Array_Aggregate
1439 Who_Cares : Node_Id;
1441 Aggr_Low : Node_Id := Empty;
1442 Aggr_High : Node_Id := Empty;
1443 -- The actual low and high bounds of this sub-aggegate
1445 Choices_Low : Node_Id := Empty;
1446 Choices_High : Node_Id := Empty;
1447 -- The lowest and highest discrete choices values for a named aggregate
1449 Nb_Elements : Uint := Uint_0;
1450 -- The number of elements in a positional aggegate
1452 Others_Present : Boolean := False;
1454 Nb_Choices : Nat := 0;
1455 -- Contains the overall number of named choices in this sub-aggregate
1457 Nb_Discrete_Choices : Nat := 0;
1458 -- The overall number of discrete choices (not counting others choice)
1460 Case_Table_Size : Nat;
1461 -- Contains the size of the case table needed to sort aggregate choices
1463 -- Start of processing for Resolve_Array_Aggregate
1466 -- STEP 1: make sure the aggregate is correctly formatted
1468 if Present (Component_Associations (N)) then
1469 Assoc := First (Component_Associations (N));
1470 while Present (Assoc) loop
1471 Choice := First (Choices (Assoc));
1472 while Present (Choice) loop
1473 if Nkind (Choice) = N_Others_Choice then
1474 Others_Present := True;
1476 if Choice /= First (Choices (Assoc))
1477 or else Present (Next (Choice))
1480 ("OTHERS must appear alone in a choice list", Choice);
1484 if Present (Next (Assoc)) then
1486 ("OTHERS must appear last in an aggregate", Choice);
1490 if Ada_Version = Ada_83
1491 and then Assoc /= First (Component_Associations (N))
1492 and then (Nkind (Parent (N)) = N_Assignment_Statement
1494 Nkind (Parent (N)) = N_Object_Declaration)
1497 ("(Ada 83) illegal context for OTHERS choice", N);
1501 Nb_Choices := Nb_Choices + 1;
1509 -- At this point we know that the others choice, if present, is by
1510 -- itself and appears last in the aggregate. Check if we have mixed
1511 -- positional and discrete associations (other than the others choice).
1513 if Present (Expressions (N))
1514 and then (Nb_Choices > 1
1515 or else (Nb_Choices = 1 and then not Others_Present))
1518 ("named association cannot follow positional association",
1519 First (Choices (First (Component_Associations (N)))));
1523 -- Test for the validity of an others choice if present
1525 if Others_Present and then not Others_Allowed then
1527 ("OTHERS choice not allowed here",
1528 First (Choices (First (Component_Associations (N)))));
1532 -- Protect against cascaded errors
1534 if Etype (Index_Typ) = Any_Type then
1538 -- STEP 2: Process named components
1540 if No (Expressions (N)) then
1542 if Others_Present then
1543 Case_Table_Size := Nb_Choices - 1;
1545 Case_Table_Size := Nb_Choices;
1551 -- Denote the lowest and highest values in an aggregate choice
1555 -- High end of one range and Low end of the next. Should be
1556 -- contiguous if there is no hole in the list of values.
1558 Missing_Values : Boolean;
1559 -- Set True if missing index values
1561 S_Low : Node_Id := Empty;
1562 S_High : Node_Id := Empty;
1563 -- if a choice in an aggregate is a subtype indication these
1564 -- denote the lowest and highest values of the subtype
1566 Table : Case_Table_Type (1 .. Case_Table_Size);
1567 -- Used to sort all the different choice values
1569 Single_Choice : Boolean;
1570 -- Set to true every time there is a single discrete choice in a
1571 -- discrete association
1573 Prev_Nb_Discrete_Choices : Nat;
1574 -- Used to keep track of the number of discrete choices
1575 -- in the current association.
1578 -- STEP 2 (A): Check discrete choices validity.
1580 Assoc := First (Component_Associations (N));
1581 while Present (Assoc) loop
1583 Prev_Nb_Discrete_Choices := Nb_Discrete_Choices;
1584 Choice := First (Choices (Assoc));
1588 if Nkind (Choice) = N_Others_Choice then
1589 Single_Choice := False;
1592 -- Test for subtype mark without constraint
1594 elsif Is_Entity_Name (Choice) and then
1595 Is_Type (Entity (Choice))
1597 if Base_Type (Entity (Choice)) /= Index_Base then
1599 ("invalid subtype mark in aggregate choice",
1604 elsif Nkind (Choice) = N_Subtype_Indication then
1605 Resolve_Discrete_Subtype_Indication (Choice, Index_Base);
1607 -- Does the subtype indication evaluation raise CE ?
1609 Get_Index_Bounds (Subtype_Mark (Choice), S_Low, S_High);
1610 Get_Index_Bounds (Choice, Low, High);
1611 Check_Bounds (S_Low, S_High, Low, High);
1613 else -- Choice is a range or an expression
1614 Resolve (Choice, Index_Base);
1615 Check_Unset_Reference (Choice);
1616 Check_Non_Static_Context (Choice);
1618 -- Do not range check a choice. This check is redundant
1619 -- since this test is already performed when we check
1620 -- that the bounds of the array aggregate are within
1623 Set_Do_Range_Check (Choice, False);
1626 -- If we could not resolve the discrete choice stop here
1628 if Etype (Choice) = Any_Type then
1631 -- If the discrete choice raises CE get its original bounds.
1633 elsif Nkind (Choice) = N_Raise_Constraint_Error then
1634 Set_Raises_Constraint_Error (N);
1635 Get_Index_Bounds (Original_Node (Choice), Low, High);
1637 -- Otherwise get its bounds as usual
1640 Get_Index_Bounds (Choice, Low, High);
1643 if (Dynamic_Or_Null_Range (Low, High)
1644 or else (Nkind (Choice) = N_Subtype_Indication
1646 Dynamic_Or_Null_Range (S_Low, S_High)))
1647 and then Nb_Choices /= 1
1650 ("dynamic or empty choice in aggregate " &
1651 "must be the only choice", Choice);
1655 Nb_Discrete_Choices := Nb_Discrete_Choices + 1;
1656 Table (Nb_Discrete_Choices).Choice_Lo := Low;
1657 Table (Nb_Discrete_Choices).Choice_Hi := High;
1662 -- Check if we have a single discrete choice and whether
1663 -- this discrete choice specifies a single value.
1666 (Nb_Discrete_Choices = Prev_Nb_Discrete_Choices + 1)
1667 and then (Low = High);
1673 -- Ada 2005 (AI-231)
1675 Check_Can_Never_Be_Null (N, Expression (Assoc));
1677 -- Ada 2005 (AI-287): In case of default initialized component
1678 -- we delay the resolution to the expansion phase
1680 if Box_Present (Assoc) then
1682 -- Ada 2005 (AI-287): In case of default initialization
1683 -- of a component the expander will generate calls to
1684 -- the corresponding initialization subprogram.
1688 elsif not Resolve_Aggr_Expr (Expression (Assoc),
1689 Single_Elmt => Single_Choice)
1697 -- If aggregate contains more than one choice then these must be
1698 -- static. Sort them and check that they are contiguous
1700 if Nb_Discrete_Choices > 1 then
1701 Sort_Case_Table (Table);
1702 Missing_Values := False;
1704 Outer : for J in 1 .. Nb_Discrete_Choices - 1 loop
1705 if Expr_Value (Table (J).Choice_Hi) >=
1706 Expr_Value (Table (J + 1).Choice_Lo)
1709 ("duplicate choice values in array aggregate",
1710 Table (J).Choice_Hi);
1713 elsif not Others_Present then
1715 Hi_Val := Expr_Value (Table (J).Choice_Hi);
1716 Lo_Val := Expr_Value (Table (J + 1).Choice_Lo);
1718 -- If missing values, output error messages
1720 if Lo_Val - Hi_Val > 1 then
1722 -- Header message if not first missing value
1724 if not Missing_Values then
1726 ("missing index value(s) in array aggregate", N);
1727 Missing_Values := True;
1730 -- Output values of missing indexes
1732 Lo_Val := Lo_Val - 1;
1733 Hi_Val := Hi_Val + 1;
1735 -- Enumeration type case
1737 if Is_Enumeration_Type (Index_Typ) then
1740 (Get_Enum_Lit_From_Pos
1741 (Index_Typ, Hi_Val, Loc));
1743 if Lo_Val = Hi_Val then
1744 Error_Msg_N ("\ %", N);
1748 (Get_Enum_Lit_From_Pos
1749 (Index_Typ, Lo_Val, Loc));
1750 Error_Msg_N ("\ % .. %", N);
1753 -- Integer types case
1756 Error_Msg_Uint_1 := Hi_Val;
1758 if Lo_Val = Hi_Val then
1759 Error_Msg_N ("\ ^", N);
1761 Error_Msg_Uint_2 := Lo_Val;
1762 Error_Msg_N ("\ ^ .. ^", N);
1769 if Missing_Values then
1770 Set_Etype (N, Any_Composite);
1775 -- STEP 2 (B): Compute aggregate bounds and min/max choices values
1777 if Nb_Discrete_Choices > 0 then
1778 Choices_Low := Table (1).Choice_Lo;
1779 Choices_High := Table (Nb_Discrete_Choices).Choice_Hi;
1782 if Others_Present then
1783 Get_Index_Bounds (Index_Constr, Aggr_Low, Aggr_High);
1786 Aggr_Low := Choices_Low;
1787 Aggr_High := Choices_High;
1791 -- STEP 3: Process positional components
1794 -- STEP 3 (A): Process positional elements
1796 Expr := First (Expressions (N));
1797 Nb_Elements := Uint_0;
1798 while Present (Expr) loop
1799 Nb_Elements := Nb_Elements + 1;
1801 Check_Can_Never_Be_Null (N, Expr); -- Ada 2005 (AI-231)
1803 if not Resolve_Aggr_Expr (Expr, Single_Elmt => True) then
1810 if Others_Present then
1811 Assoc := Last (Component_Associations (N));
1813 Check_Can_Never_Be_Null
1814 (N, Expression (Assoc)); -- Ada 2005 (AI-231)
1816 -- Ada 2005 (AI-287): In case of default initialized component
1817 -- we delay the resolution to the expansion phase.
1819 if Box_Present (Assoc) then
1821 -- Ada 2005 (AI-287): In case of default initialization
1822 -- of a component the expander will generate calls to
1823 -- the corresponding initialization subprogram.
1827 elsif not Resolve_Aggr_Expr (Expression (Assoc),
1828 Single_Elmt => False)
1834 -- STEP 3 (B): Compute the aggregate bounds
1836 if Others_Present then
1837 Get_Index_Bounds (Index_Constr, Aggr_Low, Aggr_High);
1840 if Others_Allowed then
1841 Get_Index_Bounds (Index_Constr, Aggr_Low, Who_Cares);
1843 Aggr_Low := Index_Typ_Low;
1846 Aggr_High := Add (Nb_Elements - 1, To => Aggr_Low);
1847 Check_Bound (Index_Base_High, Aggr_High);
1851 -- STEP 4: Perform static aggregate checks and save the bounds
1855 Check_Bounds (Index_Typ_Low, Index_Typ_High, Aggr_Low, Aggr_High);
1856 Check_Bounds (Index_Base_Low, Index_Base_High, Aggr_Low, Aggr_High);
1860 if Others_Present and then Nb_Discrete_Choices > 0 then
1861 Check_Bounds (Aggr_Low, Aggr_High, Choices_Low, Choices_High);
1862 Check_Bounds (Index_Typ_Low, Index_Typ_High,
1863 Choices_Low, Choices_High);
1864 Check_Bounds (Index_Base_Low, Index_Base_High,
1865 Choices_Low, Choices_High);
1869 elsif Others_Present and then Nb_Elements > 0 then
1870 Check_Length (Aggr_Low, Aggr_High, Nb_Elements);
1871 Check_Length (Index_Typ_Low, Index_Typ_High, Nb_Elements);
1872 Check_Length (Index_Base_Low, Index_Base_High, Nb_Elements);
1876 if Raises_Constraint_Error (Aggr_Low)
1877 or else Raises_Constraint_Error (Aggr_High)
1879 Set_Raises_Constraint_Error (N);
1882 Aggr_Low := Duplicate_Subexpr (Aggr_Low);
1884 -- Do not duplicate Aggr_High if Aggr_High = Aggr_Low + Nb_Elements
1885 -- since the addition node returned by Add is not yet analyzed. Attach
1886 -- to tree and analyze first. Reset analyzed flag to insure it will get
1887 -- analyzed when it is a literal bound whose type must be properly
1890 if Others_Present or else Nb_Discrete_Choices > 0 then
1891 Aggr_High := Duplicate_Subexpr (Aggr_High);
1893 if Etype (Aggr_High) = Universal_Integer then
1894 Set_Analyzed (Aggr_High, False);
1898 Set_Aggregate_Bounds
1899 (N, Make_Range (Loc, Low_Bound => Aggr_Low, High_Bound => Aggr_High));
1901 -- The bounds may contain expressions that must be inserted upwards.
1902 -- Attach them fully to the tree. After analysis, remove side effects
1903 -- from upper bound, if still needed.
1905 Set_Parent (Aggregate_Bounds (N), N);
1906 Analyze_And_Resolve (Aggregate_Bounds (N), Index_Typ);
1907 Check_Unset_Reference (Aggregate_Bounds (N));
1909 if not Others_Present and then Nb_Discrete_Choices = 0 then
1910 Set_High_Bound (Aggregate_Bounds (N),
1911 Duplicate_Subexpr (High_Bound (Aggregate_Bounds (N))));
1915 end Resolve_Array_Aggregate;
1917 ---------------------------------
1918 -- Resolve_Extension_Aggregate --
1919 ---------------------------------
1921 -- There are two cases to consider:
1923 -- a) If the ancestor part is a type mark, the components needed are
1924 -- the difference between the components of the expected type and the
1925 -- components of the given type mark.
1927 -- b) If the ancestor part is an expression, it must be unambiguous,
1928 -- and once we have its type we can also compute the needed components
1929 -- as in the previous case. In both cases, if the ancestor type is not
1930 -- the immediate ancestor, we have to build this ancestor recursively.
1932 -- In both cases discriminants of the ancestor type do not play a
1933 -- role in the resolution of the needed components, because inherited
1934 -- discriminants cannot be used in a type extension. As a result we can
1935 -- compute independently the list of components of the ancestor type and
1936 -- of the expected type.
1938 procedure Resolve_Extension_Aggregate (N : Node_Id; Typ : Entity_Id) is
1939 A : constant Node_Id := Ancestor_Part (N);
1944 function Valid_Ancestor_Type return Boolean;
1945 -- Verify that the type of the ancestor part is a non-private ancestor
1946 -- of the expected type.
1948 -------------------------
1949 -- Valid_Ancestor_Type --
1950 -------------------------
1952 function Valid_Ancestor_Type return Boolean is
1953 Imm_Type : Entity_Id;
1956 Imm_Type := Base_Type (Typ);
1957 while Is_Derived_Type (Imm_Type)
1958 and then Etype (Imm_Type) /= Base_Type (A_Type)
1960 Imm_Type := Etype (Base_Type (Imm_Type));
1963 if Etype (Imm_Type) /= Base_Type (A_Type) then
1964 Error_Msg_NE ("expect ancestor type of &", A, Typ);
1969 end Valid_Ancestor_Type;
1971 -- Start of processing for Resolve_Extension_Aggregate
1976 if not Is_Tagged_Type (Typ) then
1977 Error_Msg_N ("type of extension aggregate must be tagged", N);
1980 elsif Is_Limited_Type (Typ) then
1982 -- Ada 2005 (AI-287): Limited aggregates are allowed
1984 if Ada_Version < Ada_05 then
1985 Error_Msg_N ("aggregate type cannot be limited", N);
1986 Explain_Limited_Type (Typ, N);
1990 elsif Is_Class_Wide_Type (Typ) then
1991 Error_Msg_N ("aggregate cannot be of a class-wide type", N);
1995 if Is_Entity_Name (A)
1996 and then Is_Type (Entity (A))
1998 A_Type := Get_Full_View (Entity (A));
2000 if Valid_Ancestor_Type then
2001 Set_Entity (A, A_Type);
2002 Set_Etype (A, A_Type);
2004 Validate_Ancestor_Part (N);
2005 Resolve_Record_Aggregate (N, Typ);
2008 elsif Nkind (A) /= N_Aggregate then
2009 if Is_Overloaded (A) then
2011 Get_First_Interp (A, I, It);
2013 while Present (It.Typ) loop
2015 if Is_Tagged_Type (It.Typ)
2016 and then not Is_Limited_Type (It.Typ)
2018 if A_Type /= Any_Type then
2019 Error_Msg_N ("cannot resolve expression", A);
2026 Get_Next_Interp (I, It);
2029 if A_Type = Any_Type then
2031 ("ancestor part must be non-limited tagged type", A);
2036 A_Type := Etype (A);
2039 if Valid_Ancestor_Type then
2040 Resolve (A, A_Type);
2041 Check_Unset_Reference (A);
2042 Check_Non_Static_Context (A);
2044 if Is_Class_Wide_Type (Etype (A))
2045 and then Nkind (Original_Node (A)) = N_Function_Call
2047 -- If the ancestor part is a dispatching call, it appears
2048 -- statically to be a legal ancestor, but it yields any
2049 -- member of the class, and it is not possible to determine
2050 -- whether it is an ancestor of the extension aggregate (much
2051 -- less which ancestor). It is not possible to determine the
2052 -- required components of the extension part.
2054 Error_Msg_N ("ancestor part must be statically tagged", A);
2056 Resolve_Record_Aggregate (N, Typ);
2061 Error_Msg_N (" No unique type for this aggregate", A);
2063 end Resolve_Extension_Aggregate;
2065 ------------------------------
2066 -- Resolve_Record_Aggregate --
2067 ------------------------------
2069 procedure Resolve_Record_Aggregate (N : Node_Id; Typ : Entity_Id) is
2070 New_Assoc_List : constant List_Id := New_List;
2071 New_Assoc : Node_Id;
2072 -- New_Assoc_List is the newly built list of N_Component_Association
2073 -- nodes. New_Assoc is one such N_Component_Association node in it.
2074 -- Please note that while Assoc and New_Assoc contain the same
2075 -- kind of nodes, they are used to iterate over two different
2076 -- N_Component_Association lists.
2078 Others_Etype : Entity_Id := Empty;
2079 -- This variable is used to save the Etype of the last record component
2080 -- that takes its value from the others choice. Its purpose is:
2082 -- (a) make sure the others choice is useful
2084 -- (b) make sure the type of all the components whose value is
2085 -- subsumed by the others choice are the same.
2087 -- This variable is updated as a side effect of function Get_Value
2089 Mbox_Present : Boolean := False;
2090 Others_Mbox : Boolean := False;
2091 -- Ada 2005 (AI-287): Variables used in case of default initialization
2092 -- to provide a functionality similar to Others_Etype. Mbox_Present
2093 -- indicates that the component takes its default initialization;
2094 -- Others_Mbox indicates that at least one component takes its default
2095 -- initialization. Similar to Others_Etype, they are also updated as a
2096 -- side effect of function Get_Value.
2098 procedure Add_Association
2099 (Component : Entity_Id;
2101 Box_Present : Boolean := False);
2102 -- Builds a new N_Component_Association node which associates
2103 -- Component to expression Expr and adds it to the new association
2104 -- list New_Assoc_List being built.
2106 function Discr_Present (Discr : Entity_Id) return Boolean;
2107 -- If aggregate N is a regular aggregate this routine will return True.
2108 -- Otherwise, if N is an extension aggregate, Discr is a discriminant
2109 -- whose value may already have been specified by N's ancestor part,
2110 -- this routine checks whether this is indeed the case and if so
2111 -- returns False, signaling that no value for Discr should appear in the
2112 -- N's aggregate part. Also, in this case, the routine appends to
2113 -- New_Assoc_List Discr the discriminant value specified in the ancestor
2119 Consider_Others_Choice : Boolean := False)
2121 -- Given a record component stored in parameter Compon, the
2122 -- following function returns its value as it appears in the list
2123 -- From, which is a list of N_Component_Association nodes. If no
2124 -- component association has a choice for the searched component,
2125 -- the value provided by the others choice is returned, if there
2126 -- is one and Consider_Others_Choice is set to true. Otherwise
2127 -- Empty is returned. If there is more than one component association
2128 -- giving a value for the searched record component, an error message
2129 -- is emitted and the first found value is returned.
2131 -- If Consider_Others_Choice is set and the returned expression comes
2132 -- from the others choice, then Others_Etype is set as a side effect.
2133 -- An error message is emitted if the components taking their value
2134 -- from the others choice do not have same type.
2136 procedure Resolve_Aggr_Expr (Expr : Node_Id; Component : Node_Id);
2137 -- Analyzes and resolves expression Expr against the Etype of the
2138 -- Component. This routine also applies all appropriate checks to Expr.
2139 -- It finally saves a Expr in the newly created association list that
2140 -- will be attached to the final record aggregate. Note that if the
2141 -- Parent pointer of Expr is not set then Expr was produced with a
2142 -- New_Copy_Tree or some such.
2144 ---------------------
2145 -- Add_Association --
2146 ---------------------
2148 procedure Add_Association
2149 (Component : Entity_Id;
2151 Box_Present : Boolean := False)
2153 Choice_List : constant List_Id := New_List;
2154 New_Assoc : Node_Id;
2157 Append (New_Occurrence_Of (Component, Sloc (Expr)), Choice_List);
2159 Make_Component_Association (Sloc (Expr),
2160 Choices => Choice_List,
2162 Box_Present => Box_Present);
2163 Append (New_Assoc, New_Assoc_List);
2164 end Add_Association;
2170 function Discr_Present (Discr : Entity_Id) return Boolean is
2171 Regular_Aggr : constant Boolean := Nkind (N) /= N_Extension_Aggregate;
2176 Discr_Expr : Node_Id;
2178 Ancestor_Typ : Entity_Id;
2179 Orig_Discr : Entity_Id;
2181 D_Val : Elmt_Id := No_Elmt; -- stop junk warning
2183 Ancestor_Is_Subtyp : Boolean;
2186 if Regular_Aggr then
2190 Ancestor := Ancestor_Part (N);
2191 Ancestor_Typ := Etype (Ancestor);
2192 Loc := Sloc (Ancestor);
2194 Ancestor_Is_Subtyp :=
2195 Is_Entity_Name (Ancestor) and then Is_Type (Entity (Ancestor));
2197 -- If the ancestor part has no discriminants clearly N's aggregate
2198 -- part must provide a value for Discr.
2200 if not Has_Discriminants (Ancestor_Typ) then
2203 -- If the ancestor part is an unconstrained subtype mark then the
2204 -- Discr must be present in N's aggregate part.
2206 elsif Ancestor_Is_Subtyp
2207 and then not Is_Constrained (Entity (Ancestor))
2212 -- Now look to see if Discr was specified in the ancestor part.
2214 Orig_Discr := Original_Record_Component (Discr);
2215 D := First_Discriminant (Ancestor_Typ);
2217 if Ancestor_Is_Subtyp then
2218 D_Val := First_Elmt (Discriminant_Constraint (Entity (Ancestor)));
2221 while Present (D) loop
2222 -- If Ancestor has already specified Disc value than
2223 -- insert its value in the final aggregate.
2225 if Original_Record_Component (D) = Orig_Discr then
2226 if Ancestor_Is_Subtyp then
2227 Discr_Expr := New_Copy_Tree (Node (D_Val));
2230 Make_Selected_Component (Loc,
2231 Prefix => Duplicate_Subexpr (Ancestor),
2232 Selector_Name => New_Occurrence_Of (Discr, Loc));
2235 Resolve_Aggr_Expr (Discr_Expr, Discr);
2239 Next_Discriminant (D);
2241 if Ancestor_Is_Subtyp then
2256 Consider_Others_Choice : Boolean := False)
2260 Expr : Node_Id := Empty;
2261 Selector_Name : Node_Id;
2263 procedure Check_Non_Limited_Type;
2264 -- Relax check to allow the default initialization of limited types.
2267 -- C : Lim := (..., others => <>);
2270 ----------------------------
2271 -- Check_Non_Limited_Type --
2272 ----------------------------
2274 procedure Check_Non_Limited_Type is
2276 if Is_Limited_Type (Etype (Compon))
2277 and then Comes_From_Source (Compon)
2278 and then not In_Instance_Body
2280 -- Ada 2005 (AI-287): Limited aggregates are allowed
2282 if Ada_Version >= Ada_05
2283 and then Present (Expression (Assoc))
2284 and then Nkind (Expression (Assoc)) = N_Aggregate
2289 ("initialization not allowed for limited types", N);
2290 Explain_Limited_Type (Etype (Compon), Compon);
2294 end Check_Non_Limited_Type;
2296 -- Start of processing for Get_Value
2299 Mbox_Present := False;
2301 if Present (From) then
2302 Assoc := First (From);
2307 while Present (Assoc) loop
2308 Selector_Name := First (Choices (Assoc));
2309 while Present (Selector_Name) loop
2310 if Nkind (Selector_Name) = N_Others_Choice then
2311 if Consider_Others_Choice and then No (Expr) then
2313 -- We need to duplicate the expression for each
2314 -- successive component covered by the others choice.
2315 -- This is redundant if the others_choice covers only
2316 -- one component (small optimization possible???), but
2317 -- indispensable otherwise, because each one must be
2318 -- expanded individually to preserve side-effects.
2320 -- Ada 2005 (AI-287): In case of default initialization
2321 -- of components, we duplicate the corresponding default
2322 -- expression (from the record type declaration).
2324 if Box_Present (Assoc) then
2325 Others_Mbox := True;
2326 Mbox_Present := True;
2328 if Expander_Active then
2329 return New_Copy_Tree (Expression (Parent (Compon)));
2331 return Expression (Parent (Compon));
2335 Check_Non_Limited_Type;
2337 if Present (Others_Etype) and then
2338 Base_Type (Others_Etype) /= Base_Type (Etype
2341 Error_Msg_N ("components in OTHERS choice must " &
2342 "have same type", Selector_Name);
2345 Others_Etype := Etype (Compon);
2347 if Expander_Active then
2348 return New_Copy_Tree (Expression (Assoc));
2350 return Expression (Assoc);
2355 elsif Chars (Compon) = Chars (Selector_Name) then
2358 -- Ada 2005 (AI-231)
2360 if Ada_Version >= Ada_05
2361 and then Present (Expression (Assoc))
2362 and then Nkind (Expression (Assoc)) = N_Null
2363 and then Can_Never_Be_Null (Compon)
2366 ("(Ada 2005) NULL not allowed in null-excluding " &
2367 "components", Expression (Assoc));
2370 -- We need to duplicate the expression when several
2371 -- components are grouped together with a "|" choice.
2372 -- For instance "filed1 | filed2 => Expr"
2374 -- Ada 2005 (AI-287)
2376 if Box_Present (Assoc) then
2377 Mbox_Present := True;
2379 -- Duplicate the default expression of the component
2380 -- from the record type declaration
2382 if Present (Next (Selector_Name)) then
2384 New_Copy_Tree (Expression (Parent (Compon)));
2386 Expr := Expression (Parent (Compon));
2390 Check_Non_Limited_Type;
2392 if Present (Next (Selector_Name)) then
2393 Expr := New_Copy_Tree (Expression (Assoc));
2395 Expr := Expression (Assoc);
2399 Generate_Reference (Compon, Selector_Name);
2403 ("more than one value supplied for &",
2404 Selector_Name, Compon);
2409 Next (Selector_Name);
2418 -----------------------
2419 -- Resolve_Aggr_Expr --
2420 -----------------------
2422 procedure Resolve_Aggr_Expr (Expr : Node_Id; Component : Node_Id) is
2423 New_C : Entity_Id := Component;
2424 Expr_Type : Entity_Id := Empty;
2426 function Has_Expansion_Delayed (Expr : Node_Id) return Boolean;
2427 -- If the expression is an aggregate (possibly qualified) then its
2428 -- expansion is delayed until the enclosing aggregate is expanded
2429 -- into assignments. In that case, do not generate checks on the
2430 -- expression, because they will be generated later, and will other-
2431 -- wise force a copy (to remove side-effects) that would leave a
2432 -- dynamic-sized aggregate in the code, something that gigi cannot
2436 -- Set to True if the resolved Expr node needs to be relocated
2437 -- when attached to the newly created association list. This node
2438 -- need not be relocated if its parent pointer is not set.
2439 -- In fact in this case Expr is the output of a New_Copy_Tree call.
2440 -- if Relocate is True then we have analyzed the expression node
2441 -- in the original aggregate and hence it needs to be relocated
2442 -- when moved over the new association list.
2444 function Has_Expansion_Delayed (Expr : Node_Id) return Boolean is
2445 Kind : constant Node_Kind := Nkind (Expr);
2448 return ((Kind = N_Aggregate
2449 or else Kind = N_Extension_Aggregate)
2450 and then Present (Etype (Expr))
2451 and then Is_Record_Type (Etype (Expr))
2452 and then Expansion_Delayed (Expr))
2454 or else (Kind = N_Qualified_Expression
2455 and then Has_Expansion_Delayed (Expression (Expr)));
2456 end Has_Expansion_Delayed;
2458 -- Start of processing for Resolve_Aggr_Expr
2461 -- If the type of the component is elementary or the type of the
2462 -- aggregate does not contain discriminants, use the type of the
2463 -- component to resolve Expr.
2465 if Is_Elementary_Type (Etype (Component))
2466 or else not Has_Discriminants (Etype (N))
2468 Expr_Type := Etype (Component);
2470 -- Otherwise we have to pick up the new type of the component from
2471 -- the new costrained subtype of the aggregate. In fact components
2472 -- which are of a composite type might be constrained by a
2473 -- discriminant, and we want to resolve Expr against the subtype were
2474 -- all discriminant occurrences are replaced with their actual value.
2477 New_C := First_Component (Etype (N));
2478 while Present (New_C) loop
2479 if Chars (New_C) = Chars (Component) then
2480 Expr_Type := Etype (New_C);
2484 Next_Component (New_C);
2487 pragma Assert (Present (Expr_Type));
2489 -- For each range in an array type where a discriminant has been
2490 -- replaced with the constraint, check that this range is within
2491 -- the range of the base type. This checks is done in the
2492 -- init proc for regular objects, but has to be done here for
2493 -- aggregates since no init proc is called for them.
2495 if Is_Array_Type (Expr_Type) then
2497 Index : Node_Id := First_Index (Expr_Type);
2498 -- Range of the current constrained index in the array.
2500 Orig_Index : Node_Id := First_Index (Etype (Component));
2501 -- Range corresponding to the range Index above in the
2502 -- original unconstrained record type. The bounds of this
2503 -- range may be governed by discriminants.
2505 Unconstr_Index : Node_Id := First_Index (Etype (Expr_Type));
2506 -- Range corresponding to the range Index above for the
2507 -- unconstrained array type. This range is needed to apply
2511 while Present (Index) loop
2512 if Depends_On_Discriminant (Orig_Index) then
2513 Apply_Range_Check (Index, Etype (Unconstr_Index));
2517 Next_Index (Orig_Index);
2518 Next_Index (Unconstr_Index);
2524 -- If the Parent pointer of Expr is not set, Expr is an expression
2525 -- duplicated by New_Tree_Copy (this happens for record aggregates
2526 -- that look like (Field1 | Filed2 => Expr) or (others => Expr)).
2527 -- Such a duplicated expression must be attached to the tree
2528 -- before analysis and resolution to enforce the rule that a tree
2529 -- fragment should never be analyzed or resolved unless it is
2530 -- attached to the current compilation unit.
2532 if No (Parent (Expr)) then
2533 Set_Parent (Expr, N);
2539 Analyze_And_Resolve (Expr, Expr_Type);
2540 Check_Non_Static_Context (Expr);
2541 Check_Unset_Reference (Expr);
2543 if not Has_Expansion_Delayed (Expr) then
2544 Aggregate_Constraint_Checks (Expr, Expr_Type);
2547 if Raises_Constraint_Error (Expr) then
2548 Set_Raises_Constraint_Error (N);
2552 Add_Association (New_C, Relocate_Node (Expr));
2554 Add_Association (New_C, Expr);
2556 end Resolve_Aggr_Expr;
2558 -- Resolve_Record_Aggregate local variables
2561 -- N_Component_Association node belonging to the input aggregate N
2564 Positional_Expr : Node_Id;
2565 Component : Entity_Id;
2566 Component_Elmt : Elmt_Id;
2568 Components : constant Elist_Id := New_Elmt_List;
2569 -- Components is the list of the record components whose value must
2570 -- be provided in the aggregate. This list does include discriminants.
2572 -- Start of processing for Resolve_Record_Aggregate
2575 -- We may end up calling Duplicate_Subexpr on expressions that are
2576 -- attached to New_Assoc_List. For this reason we need to attach it
2577 -- to the tree by setting its parent pointer to N. This parent point
2578 -- will change in STEP 8 below.
2580 Set_Parent (New_Assoc_List, N);
2582 -- STEP 1: abstract type and null record verification
2584 if Is_Abstract (Typ) then
2585 Error_Msg_N ("type of aggregate cannot be abstract", N);
2588 if No (First_Entity (Typ)) and then Null_Record_Present (N) then
2592 elsif Present (First_Entity (Typ))
2593 and then Null_Record_Present (N)
2594 and then not Is_Tagged_Type (Typ)
2596 Error_Msg_N ("record aggregate cannot be null", N);
2599 elsif No (First_Entity (Typ)) then
2600 Error_Msg_N ("record aggregate must be null", N);
2604 -- STEP 2: Verify aggregate structure
2607 Selector_Name : Node_Id;
2608 Bad_Aggregate : Boolean := False;
2611 if Present (Component_Associations (N)) then
2612 Assoc := First (Component_Associations (N));
2617 while Present (Assoc) loop
2618 Selector_Name := First (Choices (Assoc));
2619 while Present (Selector_Name) loop
2620 if Nkind (Selector_Name) = N_Identifier then
2623 elsif Nkind (Selector_Name) = N_Others_Choice then
2624 if Selector_Name /= First (Choices (Assoc))
2625 or else Present (Next (Selector_Name))
2627 Error_Msg_N ("OTHERS must appear alone in a choice list",
2631 elsif Present (Next (Assoc)) then
2632 Error_Msg_N ("OTHERS must appear last in an aggregate",
2639 ("selector name should be identifier or OTHERS",
2641 Bad_Aggregate := True;
2644 Next (Selector_Name);
2650 if Bad_Aggregate then
2655 -- STEP 3: Find discriminant Values
2658 Discrim : Entity_Id;
2659 Missing_Discriminants : Boolean := False;
2662 if Present (Expressions (N)) then
2663 Positional_Expr := First (Expressions (N));
2665 Positional_Expr := Empty;
2668 if Has_Discriminants (Typ) then
2669 Discrim := First_Discriminant (Typ);
2674 -- First find the discriminant values in the positional components
2676 while Present (Discrim) and then Present (Positional_Expr) loop
2677 if Discr_Present (Discrim) then
2678 Resolve_Aggr_Expr (Positional_Expr, Discrim);
2680 -- Ada 2005 (AI-231)
2682 if Ada_Version >= Ada_05
2683 and then Nkind (Positional_Expr) = N_Null
2684 and then Can_Never_Be_Null (Discrim)
2687 ("(Ada 2005) NULL not allowed in null-excluding " &
2688 "components", Positional_Expr);
2691 Next (Positional_Expr);
2694 if Present (Get_Value (Discrim, Component_Associations (N))) then
2696 ("more than one value supplied for discriminant&",
2700 Next_Discriminant (Discrim);
2703 -- Find remaining discriminant values, if any, among named components
2705 while Present (Discrim) loop
2706 Expr := Get_Value (Discrim, Component_Associations (N), True);
2708 if not Discr_Present (Discrim) then
2709 if Present (Expr) then
2711 ("more than one value supplied for discriminant&",
2715 elsif No (Expr) then
2717 ("no value supplied for discriminant &", N, Discrim);
2718 Missing_Discriminants := True;
2721 Resolve_Aggr_Expr (Expr, Discrim);
2724 Next_Discriminant (Discrim);
2727 if Missing_Discriminants then
2731 -- At this point and until the beginning of STEP 6, New_Assoc_List
2732 -- contains only the discriminants and their values.
2736 -- STEP 4: Set the Etype of the record aggregate
2738 -- ??? This code is pretty much a copy of Sem_Ch3.Build_Subtype. That
2739 -- routine should really be exported in sem_util or some such and used
2740 -- in sem_ch3 and here rather than have a copy of the code which is a
2741 -- maintenance nightmare.
2743 -- ??? Performace WARNING. The current implementation creates a new
2744 -- itype for all aggregates whose base type is discriminated.
2745 -- This means that for record aggregates nested inside an array
2746 -- aggregate we will create a new itype for each record aggregate
2747 -- if the array cmponent type has discriminants. For large aggregates
2748 -- this may be a problem. What should be done in this case is
2749 -- to reuse itypes as much as possible.
2751 if Has_Discriminants (Typ) then
2752 Build_Constrained_Itype : declare
2753 Loc : constant Source_Ptr := Sloc (N);
2755 Subtyp_Decl : Node_Id;
2758 C : constant List_Id := New_List;
2761 New_Assoc := First (New_Assoc_List);
2762 while Present (New_Assoc) loop
2763 Append (Duplicate_Subexpr (Expression (New_Assoc)), To => C);
2768 Make_Subtype_Indication (Loc,
2769 Subtype_Mark => New_Occurrence_Of (Base_Type (Typ), Loc),
2770 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
2772 Def_Id := Create_Itype (Ekind (Typ), N);
2775 Make_Subtype_Declaration (Loc,
2776 Defining_Identifier => Def_Id,
2777 Subtype_Indication => Indic);
2778 Set_Parent (Subtyp_Decl, Parent (N));
2780 -- Itypes must be analyzed with checks off (see itypes.ads).
2782 Analyze (Subtyp_Decl, Suppress => All_Checks);
2784 Set_Etype (N, Def_Id);
2785 Check_Static_Discriminated_Subtype
2786 (Def_Id, Expression (First (New_Assoc_List)));
2787 end Build_Constrained_Itype;
2793 -- STEP 5: Get remaining components according to discriminant values
2796 Record_Def : Node_Id;
2797 Parent_Typ : Entity_Id;
2798 Root_Typ : Entity_Id;
2799 Parent_Typ_List : Elist_Id;
2800 Parent_Elmt : Elmt_Id;
2801 Errors_Found : Boolean := False;
2805 if Is_Derived_Type (Typ) and then Is_Tagged_Type (Typ) then
2806 Parent_Typ_List := New_Elmt_List;
2808 -- If this is an extension aggregate, the component list must
2809 -- include all components that are not in the given ancestor
2810 -- type. Otherwise, the component list must include components
2811 -- of all ancestors, starting with the root.
2813 if Nkind (N) = N_Extension_Aggregate then
2814 Root_Typ := Base_Type (Etype (Ancestor_Part (N)));
2816 Root_Typ := Root_Type (Typ);
2818 if Nkind (Parent (Base_Type (Root_Typ)))
2819 = N_Private_Type_Declaration
2822 ("type of aggregate has private ancestor&!",
2824 Error_Msg_N ("must use extension aggregate!", N);
2828 Dnode := Declaration_Node (Base_Type (Root_Typ));
2830 -- If we don't get a full declaration, then we have some
2831 -- error which will get signalled later so skip this part.
2832 -- Otherwise, gather components of root that apply to the
2833 -- aggregate type. We use the base type in case there is an
2834 -- applicable stored constraint that renames the discriminants
2837 if Nkind (Dnode) = N_Full_Type_Declaration then
2838 Record_Def := Type_Definition (Dnode);
2839 Gather_Components (Base_Type (Typ),
2840 Component_List (Record_Def),
2841 Governed_By => New_Assoc_List,
2843 Report_Errors => Errors_Found);
2847 Parent_Typ := Base_Type (Typ);
2848 while Parent_Typ /= Root_Typ loop
2850 Prepend_Elmt (Parent_Typ, To => Parent_Typ_List);
2851 Parent_Typ := Etype (Parent_Typ);
2853 if Nkind (Parent (Base_Type (Parent_Typ))) =
2854 N_Private_Type_Declaration
2855 or else Nkind (Parent (Base_Type (Parent_Typ))) =
2856 N_Private_Extension_Declaration
2858 if Nkind (N) /= N_Extension_Aggregate then
2860 ("type of aggregate has private ancestor&!",
2862 Error_Msg_N ("must use extension aggregate!", N);
2865 elsif Parent_Typ /= Root_Typ then
2867 ("ancestor part of aggregate must be private type&",
2868 Ancestor_Part (N), Parent_Typ);
2874 -- Now collect components from all other ancestors.
2876 Parent_Elmt := First_Elmt (Parent_Typ_List);
2877 while Present (Parent_Elmt) loop
2878 Parent_Typ := Node (Parent_Elmt);
2879 Record_Def := Type_Definition (Parent (Base_Type (Parent_Typ)));
2880 Gather_Components (Empty,
2881 Component_List (Record_Extension_Part (Record_Def)),
2882 Governed_By => New_Assoc_List,
2884 Report_Errors => Errors_Found);
2886 Next_Elmt (Parent_Elmt);
2890 Record_Def := Type_Definition (Parent (Base_Type (Typ)));
2892 if Null_Present (Record_Def) then
2895 Gather_Components (Base_Type (Typ),
2896 Component_List (Record_Def),
2897 Governed_By => New_Assoc_List,
2899 Report_Errors => Errors_Found);
2903 if Errors_Found then
2908 -- STEP 6: Find component Values
2911 Component_Elmt := First_Elmt (Components);
2913 -- First scan the remaining positional associations in the aggregate.
2914 -- Remember that at this point Positional_Expr contains the current
2915 -- positional association if any is left after looking for discriminant
2916 -- values in step 3.
2918 while Present (Positional_Expr) and then Present (Component_Elmt) loop
2919 Component := Node (Component_Elmt);
2920 Resolve_Aggr_Expr (Positional_Expr, Component);
2922 -- Ada 2005 (AI-231)
2924 if Ada_Version >= Ada_05
2925 and then Nkind (Positional_Expr) = N_Null
2926 and then Can_Never_Be_Null (Component)
2929 ("(Ada 2005) NULL not allowed in null-excluding components",
2933 if Present (Get_Value (Component, Component_Associations (N))) then
2935 ("more than one value supplied for Component &", N, Component);
2938 Next (Positional_Expr);
2939 Next_Elmt (Component_Elmt);
2942 if Present (Positional_Expr) then
2944 ("too many components for record aggregate", Positional_Expr);
2947 -- Now scan for the named arguments of the aggregate
2949 while Present (Component_Elmt) loop
2950 Component := Node (Component_Elmt);
2951 Expr := Get_Value (Component, Component_Associations (N), True);
2953 -- Ada 2005 (AI-287): Default initialized limited component are
2954 -- passed to the expander, that will generate calls to the
2955 -- corresponding IP.
2957 if Mbox_Present and then Is_Limited_Type (Etype (Component)) then
2959 (Component => Component,
2961 Box_Present => True);
2963 -- Ada 2005 (AI-287): No value supplied for component
2965 elsif Mbox_Present and No (Expr) then
2968 elsif No (Expr) then
2969 Error_Msg_NE ("no value supplied for component &!", N, Component);
2972 Resolve_Aggr_Expr (Expr, Component);
2975 Next_Elmt (Component_Elmt);
2978 -- STEP 7: check for invalid components + check type in choice list
2985 -- Type of first component in choice list
2988 if Present (Component_Associations (N)) then
2989 Assoc := First (Component_Associations (N));
2994 Verification : while Present (Assoc) loop
2995 Selectr := First (Choices (Assoc));
2998 if Nkind (Selectr) = N_Others_Choice then
3000 -- Ada 2005 (AI-287): others choice may have expression or mbox
3002 if No (Others_Etype)
3003 and then not Others_Mbox
3006 ("OTHERS must represent at least one component", Selectr);
3012 while Present (Selectr) loop
3013 New_Assoc := First (New_Assoc_List);
3014 while Present (New_Assoc) loop
3015 Component := First (Choices (New_Assoc));
3016 exit when Chars (Selectr) = Chars (Component);
3020 -- If no association, this is not a legal component of
3021 -- of the type in question, except if this is an internal
3022 -- component supplied by a previous expansion.
3024 if No (New_Assoc) then
3025 if Box_Present (Parent (Selectr)) then
3028 elsif Chars (Selectr) /= Name_uTag
3029 and then Chars (Selectr) /= Name_uParent
3030 and then Chars (Selectr) /= Name_uController
3032 if not Has_Discriminants (Typ) then
3033 Error_Msg_Node_2 := Typ;
3035 ("& is not a component of}",
3039 ("& is not a component of the aggregate subtype",
3043 Check_Misspelled_Component (Components, Selectr);
3046 elsif No (Typech) then
3047 Typech := Base_Type (Etype (Component));
3049 elsif Typech /= Base_Type (Etype (Component)) then
3050 if not Box_Present (Parent (Selectr)) then
3052 ("components in choice list must have same type",
3061 end loop Verification;
3064 -- STEP 8: replace the original aggregate
3067 New_Aggregate : constant Node_Id := New_Copy (N);
3070 Set_Expressions (New_Aggregate, No_List);
3071 Set_Etype (New_Aggregate, Etype (N));
3072 Set_Component_Associations (New_Aggregate, New_Assoc_List);
3074 Rewrite (N, New_Aggregate);
3076 end Resolve_Record_Aggregate;
3078 -----------------------------
3079 -- Check_Can_Never_Be_Null --
3080 -----------------------------
3082 procedure Check_Can_Never_Be_Null (N : Node_Id; Expr : Node_Id) is
3084 if Ada_Version >= Ada_05
3085 and then Nkind (Expr) = N_Null
3086 and then Can_Never_Be_Null (Etype (N))
3089 ("(Ada 2005) NULL not allowed in null-excluding components", Expr);
3091 end Check_Can_Never_Be_Null;
3093 ---------------------
3094 -- Sort_Case_Table --
3095 ---------------------
3097 procedure Sort_Case_Table (Case_Table : in out Case_Table_Type) is
3098 L : constant Int := Case_Table'First;
3099 U : constant Int := Case_Table'Last;
3108 T := Case_Table (K + 1);
3112 and then Expr_Value (Case_Table (J - 1).Choice_Lo) >
3113 Expr_Value (T.Choice_Lo)
3115 Case_Table (J) := Case_Table (J - 1);
3119 Case_Table (J) := T;
3122 end Sort_Case_Table;
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