1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2003 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_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_Ch8; use Sem_Ch8;
44 with Sem_Ch13; use Sem_Ch13;
45 with Sem_Eval; use Sem_Eval;
46 with Sem_Res; use Sem_Res;
47 with Sem_Util; use Sem_Util;
48 with Sem_Type; use Sem_Type;
49 with Sem_Warn; use Sem_Warn;
50 with Sinfo; use Sinfo;
51 with Snames; use Snames;
52 with Stringt; use Stringt;
53 with Stand; use Stand;
54 with Targparm; use Targparm;
55 with Tbuild; use Tbuild;
56 with Uintp; use Uintp;
58 with GNAT.Spelling_Checker; use GNAT.Spelling_Checker;
60 package body Sem_Aggr is
62 type Case_Bounds is record
65 Choice_Node : Node_Id;
68 type Case_Table_Type is array (Nat range <>) of Case_Bounds;
69 -- Table type used by Check_Case_Choices procedure
71 -----------------------
72 -- Local Subprograms --
73 -----------------------
75 procedure Sort_Case_Table (Case_Table : in out Case_Table_Type);
76 -- Sort the Case Table using the Lower Bound of each Choice as the key.
77 -- A simple insertion sort is used since the number of choices in a case
78 -- statement of variant part will usually be small and probably in near
81 ------------------------------------------------------
82 -- Subprograms used for RECORD AGGREGATE Processing --
83 ------------------------------------------------------
85 procedure Resolve_Record_Aggregate (N : Node_Id; Typ : Entity_Id);
86 -- This procedure performs all the semantic checks required for record
87 -- aggregates. Note that for aggregates analysis and resolution go
88 -- hand in hand. Aggregate analysis has been delayed up to here and
89 -- it is done while resolving the aggregate.
91 -- N is the N_Aggregate node.
92 -- Typ is the record type for the aggregate resolution
94 -- While performing the semantic checks, this procedure
95 -- builds a new Component_Association_List where each record field
96 -- appears alone in a Component_Choice_List along with its corresponding
97 -- expression. The record fields in the Component_Association_List
98 -- appear in the same order in which they appear in the record type Typ.
100 -- Once this new Component_Association_List is built and all the
101 -- semantic checks performed, the original aggregate subtree is replaced
102 -- with the new named record aggregate just built. Note that the subtree
103 -- substitution is performed with Rewrite so as to be
104 -- able to retrieve the original aggregate.
106 -- The aggregate subtree manipulation performed by Resolve_Record_Aggregate
107 -- yields the aggregate format expected by Gigi. Typically, this kind of
108 -- tree manipulations are done in the expander. However, because the
109 -- semantic checks that need to be performed on record aggregates really
110 -- go hand in hand with the record aggregate normalization, the aggregate
111 -- subtree transformation is performed during resolution rather than
112 -- expansion. Had we decided otherwise we would have had to duplicate
113 -- most of the code in the expansion procedure Expand_Record_Aggregate.
114 -- Note, however, that all the expansion concerning aggegates for tagged
115 -- records is done in Expand_Record_Aggregate.
117 -- The algorithm of Resolve_Record_Aggregate proceeds as follows:
119 -- 1. Make sure that the record type against which the record aggregate
120 -- has to be resolved is not abstract. Furthermore if the type is
121 -- a null aggregate make sure the input aggregate N is also null.
123 -- 2. Verify that the structure of the aggregate is that of a record
124 -- aggregate. Specifically, look for component associations and ensure
125 -- that each choice list only has identifiers or the N_Others_Choice
126 -- node. Also make sure that if present, the N_Others_Choice occurs
127 -- last and by itself.
129 -- 3. If Typ contains discriminants, the values for each discriminant
130 -- is looked for. If the record type Typ has variants, we check
131 -- that the expressions corresponding to each discriminant ruling
132 -- the (possibly nested) variant parts of Typ, are static. This
133 -- allows us to determine the variant parts to which the rest of
134 -- the aggregate must conform. The names of discriminants with their
135 -- values are saved in a new association list, New_Assoc_List which
136 -- is later augmented with the names and values of the remaining
137 -- components in the record type.
139 -- During this phase we also make sure that every discriminant is
140 -- assigned exactly one value. Note that when several values
141 -- for a given discriminant are found, semantic processing continues
142 -- looking for further errors. In this case it's the first
143 -- discriminant value found which we will be recorded.
145 -- IMPORTANT NOTE: For derived tagged types this procedure expects
146 -- First_Discriminant and Next_Discriminant to give the correct list
147 -- of discriminants, in the correct order.
149 -- 4. After all the discriminant values have been gathered, we can
150 -- set the Etype of the record aggregate. If Typ contains no
151 -- discriminants this is straightforward: the Etype of N is just
152 -- Typ, otherwise a new implicit constrained subtype of Typ is
153 -- built to be the Etype of N.
155 -- 5. Gather the remaining record components according to the discriminant
156 -- values. This involves recursively traversing the record type
157 -- structure to see what variants are selected by the given discriminant
158 -- values. This processing is a little more convoluted if Typ is a
159 -- derived tagged types since we need to retrieve the record structure
160 -- of all the ancestors of Typ.
162 -- 6. After gathering the record components we look for their values
163 -- in the record aggregate and emit appropriate error messages
164 -- should we not find such values or should they be duplicated.
166 -- 7. We then make sure no illegal component names appear in the
167 -- record aggegate and make sure that the type of the record
168 -- components appearing in a same choice list is the same.
169 -- Finally we ensure that the others choice, if present, is
170 -- used to provide the value of at least a record component.
172 -- 8. The original aggregate node is replaced with the new named
173 -- aggregate built in steps 3 through 6, as explained earlier.
175 -- Given the complexity of record aggregate resolution, the primary
176 -- goal of this routine is clarity and simplicity rather than execution
177 -- and storage efficiency. If there are only positional components in the
178 -- aggregate the running time is linear. If there are associations
179 -- the running time is still linear as long as the order of the
180 -- associations is not too far off the order of the components in the
181 -- record type. If this is not the case the running time is at worst
182 -- quadratic in the size of the association list.
184 procedure Check_Misspelled_Component
185 (Elements : Elist_Id;
186 Component : Node_Id);
187 -- Give possible misspelling diagnostic if Component is likely to be
188 -- a misspelling of one of the components of the Assoc_List.
189 -- This is called by Resolv_Aggr_Expr after producing
190 -- an invalid component error message.
192 procedure Check_Static_Discriminated_Subtype (T : Entity_Id; V : Node_Id);
193 -- An optimization: determine whether a discriminated subtype has a
194 -- static constraint, and contains array components whose length is also
195 -- static, either because they are constrained by the discriminant, or
196 -- because the original component bounds are static.
198 -----------------------------------------------------
199 -- Subprograms used for ARRAY AGGREGATE Processing --
200 -----------------------------------------------------
202 function Resolve_Array_Aggregate
205 Index_Constr : Node_Id;
206 Component_Typ : Entity_Id;
207 Others_Allowed : Boolean)
209 -- This procedure performs the semantic checks for an array aggregate.
210 -- True is returned if the aggregate resolution succeeds.
211 -- The procedure works by recursively checking each nested aggregate.
212 -- Specifically, after checking a sub-aggreate nested at the i-th level
213 -- we recursively check all the subaggregates at the i+1-st level (if any).
214 -- Note that for aggregates analysis and resolution go hand in hand.
215 -- Aggregate analysis has been delayed up to here and it is done while
216 -- resolving the aggregate.
218 -- N is the current N_Aggregate node to be checked.
220 -- Index is the index node corresponding to the array sub-aggregate that
221 -- we are currently checking (RM 4.3.3 (8)). Its Etype is the
222 -- corresponding index type (or subtype).
224 -- Index_Constr is the node giving the applicable index constraint if
225 -- any (RM 4.3.3 (10)). It "is a constraint provided by certain
226 -- contexts [...] that can be used to determine the bounds of the array
227 -- value specified by the aggregate". If Others_Allowed below is False
228 -- there is no applicable index constraint and this node is set to Index.
230 -- Component_Typ is the array component type.
232 -- Others_Allowed indicates whether an others choice is allowed
233 -- in the context where the top-level aggregate appeared.
235 -- The algorithm of Resolve_Array_Aggregate proceeds as follows:
237 -- 1. Make sure that the others choice, if present, is by itself and
238 -- appears last in the sub-aggregate. Check that we do not have
239 -- positional and named components in the array sub-aggregate (unless
240 -- the named association is an others choice). Finally if an others
241 -- choice is present, make sure it is allowed in the aggregate contex.
243 -- 2. If the array sub-aggregate contains discrete_choices:
245 -- (A) Verify their validity. Specifically verify that:
247 -- (a) If a null range is present it must be the only possible
248 -- choice in the array aggregate.
250 -- (b) Ditto for a non static range.
252 -- (c) Ditto for a non static expression.
254 -- In addition this step analyzes and resolves each discrete_choice,
255 -- making sure that its type is the type of the corresponding Index.
256 -- If we are not at the lowest array aggregate level (in the case of
257 -- multi-dimensional aggregates) then invoke Resolve_Array_Aggregate
258 -- recursively on each component expression. Otherwise, resolve the
259 -- bottom level component expressions against the expected component
260 -- type ONLY IF the component corresponds to a single discrete choice
261 -- which is not an others choice (to see why read the DELAYED
262 -- COMPONENT RESOLUTION below).
264 -- (B) Determine the bounds of the sub-aggregate and lowest and
265 -- highest choice values.
267 -- 3. For positional aggregates:
269 -- (A) Loop over the component expressions either recursively invoking
270 -- Resolve_Array_Aggregate on each of these for multi-dimensional
271 -- array aggregates or resolving the bottom level component
272 -- expressions against the expected component type.
274 -- (B) Determine the bounds of the positional sub-aggregates.
276 -- 4. Try to determine statically whether the evaluation of the array
277 -- sub-aggregate raises Constraint_Error. If yes emit proper
278 -- warnings. The precise checks are the following:
280 -- (A) Check that the index range defined by aggregate bounds is
281 -- compatible with corresponding index subtype.
282 -- We also check against the base type. In fact it could be that
283 -- Low/High bounds of the base type are static whereas those of
284 -- the index subtype are not. Thus if we can statically catch
285 -- a problem with respect to the base type we are guaranteed
286 -- that the same problem will arise with the index subtype
288 -- (B) If we are dealing with a named aggregate containing an others
289 -- choice and at least one discrete choice then make sure the range
290 -- specified by the discrete choices does not overflow the
291 -- aggregate bounds. We also check against the index type and base
292 -- type bounds for the same reasons given in (A).
294 -- (C) If we are dealing with a positional aggregate with an others
295 -- choice make sure the number of positional elements specified
296 -- does not overflow the aggregate bounds. We also check against
297 -- the index type and base type bounds as mentioned in (A).
299 -- Finally construct an N_Range node giving the sub-aggregate bounds.
300 -- Set the Aggregate_Bounds field of the sub-aggregate to be this
301 -- N_Range. The routine Array_Aggr_Subtype below uses such N_Ranges
302 -- to build the appropriate aggregate subtype. Aggregate_Bounds
303 -- information is needed during expansion.
305 -- DELAYED COMPONENT RESOLUTION: The resolution of bottom level component
306 -- expressions in an array aggregate may call Duplicate_Subexpr or some
307 -- other routine that inserts code just outside the outermost aggregate.
308 -- If the array aggregate contains discrete choices or an others choice,
309 -- this may be wrong. Consider for instance the following example.
311 -- type Rec is record
315 -- type Acc_Rec is access Rec;
316 -- Arr : array (1..3) of Acc_Rec := (1 .. 3 => new Rec);
318 -- Then the transformation of "new Rec" that occurs during resolution
319 -- entails the following code modifications
321 -- P7b : constant Acc_Rec := new Rec;
323 -- Arr : array (1..3) of Acc_Rec := (1 .. 3 => P7b);
325 -- This code transformation is clearly wrong, since we need to call
326 -- "new Rec" for each of the 3 array elements. To avoid this problem we
327 -- delay resolution of the components of non positional array aggregates
328 -- to the expansion phase. As an optimization, if the discrete choice
329 -- specifies a single value we do not delay resolution.
331 function Array_Aggr_Subtype (N : Node_Id; Typ : Node_Id) return Entity_Id;
332 -- This routine returns the type or subtype of an array aggregate.
334 -- N is the array aggregate node whose type we return.
336 -- Typ is the context type in which N occurs.
338 -- This routine creates an implicit array subtype whose bounds are
339 -- those defined by the aggregate. When this routine is invoked
340 -- Resolve_Array_Aggregate has already processed aggregate N. Thus the
341 -- Aggregate_Bounds of each sub-aggregate, is an N_Range node giving the
342 -- sub-aggregate bounds. When building the aggegate itype, this function
343 -- traverses the array aggregate N collecting such Aggregate_Bounds and
344 -- constructs the proper array aggregate itype.
346 -- Note that in the case of multidimensional aggregates each inner
347 -- sub-aggregate corresponding to a given array dimension, may provide a
348 -- different bounds. If it is possible to determine statically that
349 -- some sub-aggregates corresponding to the same index do not have the
350 -- same bounds, then a warning is emitted. If such check is not possible
351 -- statically (because some sub-aggregate bounds are dynamic expressions)
352 -- then this job is left to the expander. In all cases the particular
353 -- bounds that this function will chose for a given dimension is the first
354 -- N_Range node for a sub-aggregate corresponding to that dimension.
356 -- Note that the Raises_Constraint_Error flag of an array aggregate
357 -- whose evaluation is determined to raise CE by Resolve_Array_Aggregate,
358 -- is set in Resolve_Array_Aggregate but the aggregate is not
359 -- immediately replaced with a raise CE. In fact, Array_Aggr_Subtype must
360 -- first construct the proper itype for the aggregate (Gigi needs
361 -- this). After constructing the proper itype we will eventually replace
362 -- the top-level aggregate with a raise CE (done in Resolve_Aggregate).
363 -- Of course in cases such as:
365 -- type Arr is array (integer range <>) of Integer;
366 -- A : Arr := (positive range -1 .. 2 => 0);
368 -- The bounds of the aggregate itype are cooked up to look reasonable
369 -- (in this particular case the bounds will be 1 .. 2).
371 procedure Aggregate_Constraint_Checks
373 Check_Typ : Entity_Id);
374 -- Checks expression Exp against subtype Check_Typ. If Exp is an
375 -- aggregate and Check_Typ a constrained record type with discriminants,
376 -- we generate the appropriate discriminant checks. If Exp is an array
377 -- aggregate then emit the appropriate length checks. If Exp is a scalar
378 -- type, or a string literal, Exp is changed into Check_Typ'(Exp) to
379 -- ensure that range checks are performed at run time.
381 procedure Make_String_Into_Aggregate (N : Node_Id);
382 -- A string literal can appear in a context in which a one dimensional
383 -- array of characters is expected. This procedure simply rewrites the
384 -- string as an aggregate, prior to resolution.
386 ---------------------------------
387 -- Aggregate_Constraint_Checks --
388 ---------------------------------
390 procedure Aggregate_Constraint_Checks
392 Check_Typ : Entity_Id)
394 Exp_Typ : constant Entity_Id := Etype (Exp);
397 if Raises_Constraint_Error (Exp) then
401 -- This is really expansion activity, so make sure that expansion
402 -- is on and is allowed.
404 if not Expander_Active or else In_Default_Expression then
408 -- First check if we have to insert discriminant checks
410 if Has_Discriminants (Exp_Typ) then
411 Apply_Discriminant_Check (Exp, Check_Typ);
413 -- Next emit length checks for array aggregates
415 elsif Is_Array_Type (Exp_Typ) then
416 Apply_Length_Check (Exp, Check_Typ);
418 -- Finally emit scalar and string checks. If we are dealing with a
419 -- scalar literal we need to check by hand because the Etype of
420 -- literals is not necessarily correct.
422 elsif Is_Scalar_Type (Exp_Typ)
423 and then Compile_Time_Known_Value (Exp)
425 if Is_Out_Of_Range (Exp, Base_Type (Check_Typ)) then
426 Apply_Compile_Time_Constraint_Error
427 (Exp, "value not in range of}?", CE_Range_Check_Failed,
428 Ent => Base_Type (Check_Typ),
429 Typ => Base_Type (Check_Typ));
431 elsif Is_Out_Of_Range (Exp, Check_Typ) then
432 Apply_Compile_Time_Constraint_Error
433 (Exp, "value not in range of}?", CE_Range_Check_Failed,
437 elsif not Range_Checks_Suppressed (Check_Typ) then
438 Apply_Scalar_Range_Check (Exp, Check_Typ);
441 elsif (Is_Scalar_Type (Exp_Typ)
442 or else Nkind (Exp) = N_String_Literal)
443 and then Exp_Typ /= Check_Typ
445 if Is_Entity_Name (Exp)
446 and then Ekind (Entity (Exp)) = E_Constant
448 -- If expression is a constant, it is worthwhile checking whether
449 -- it is a bound of the type.
451 if (Is_Entity_Name (Type_Low_Bound (Check_Typ))
452 and then Entity (Exp) = Entity (Type_Low_Bound (Check_Typ)))
453 or else (Is_Entity_Name (Type_High_Bound (Check_Typ))
454 and then Entity (Exp) = Entity (Type_High_Bound (Check_Typ)))
459 Rewrite (Exp, Convert_To (Check_Typ, Relocate_Node (Exp)));
460 Analyze_And_Resolve (Exp, Check_Typ);
461 Check_Unset_Reference (Exp);
464 Rewrite (Exp, Convert_To (Check_Typ, Relocate_Node (Exp)));
465 Analyze_And_Resolve (Exp, Check_Typ);
466 Check_Unset_Reference (Exp);
469 end Aggregate_Constraint_Checks;
471 ------------------------
472 -- Array_Aggr_Subtype --
473 ------------------------
475 function Array_Aggr_Subtype
480 Aggr_Dimension : constant Pos := Number_Dimensions (Typ);
481 -- Number of aggregate index dimensions.
483 Aggr_Range : array (1 .. Aggr_Dimension) of Node_Id := (others => Empty);
484 -- Constrained N_Range of each index dimension in our aggregate itype.
486 Aggr_Low : array (1 .. Aggr_Dimension) of Node_Id := (others => Empty);
487 Aggr_High : array (1 .. Aggr_Dimension) of Node_Id := (others => Empty);
488 -- Low and High bounds for each index dimension in our aggregate itype.
490 Is_Fully_Positional : Boolean := True;
492 procedure Collect_Aggr_Bounds (N : Node_Id; Dim : Pos);
493 -- N is an array (sub-)aggregate. Dim is the dimension corresponding to
494 -- (sub-)aggregate N. This procedure collects the constrained N_Range
495 -- nodes corresponding to each index dimension of our aggregate itype.
496 -- These N_Range nodes are collected in Aggr_Range above.
497 -- Likewise collect in Aggr_Low & Aggr_High above the low and high
498 -- bounds of each index dimension. If, when collecting, two bounds
499 -- corresponding to the same dimension are static and found to differ,
500 -- then emit a warning, and mark N as raising Constraint_Error.
502 -------------------------
503 -- Collect_Aggr_Bounds --
504 -------------------------
506 procedure Collect_Aggr_Bounds (N : Node_Id; Dim : Pos) is
507 This_Range : constant Node_Id := Aggregate_Bounds (N);
508 -- The aggregate range node of this specific sub-aggregate.
510 This_Low : constant Node_Id := Low_Bound (Aggregate_Bounds (N));
511 This_High : constant Node_Id := High_Bound (Aggregate_Bounds (N));
512 -- The aggregate bounds of this specific sub-aggregate.
518 -- Collect the first N_Range for a given dimension that you find.
519 -- For a given dimension they must be all equal anyway.
521 if No (Aggr_Range (Dim)) then
522 Aggr_Low (Dim) := This_Low;
523 Aggr_High (Dim) := This_High;
524 Aggr_Range (Dim) := This_Range;
527 if Compile_Time_Known_Value (This_Low) then
528 if not Compile_Time_Known_Value (Aggr_Low (Dim)) then
529 Aggr_Low (Dim) := This_Low;
531 elsif Expr_Value (This_Low) /= Expr_Value (Aggr_Low (Dim)) then
532 Set_Raises_Constraint_Error (N);
533 Error_Msg_N ("Sub-aggregate low bound mismatch?", N);
534 Error_Msg_N ("Constraint_Error will be raised at run-time?",
539 if Compile_Time_Known_Value (This_High) then
540 if not Compile_Time_Known_Value (Aggr_High (Dim)) then
541 Aggr_High (Dim) := This_High;
544 Expr_Value (This_High) /= Expr_Value (Aggr_High (Dim))
546 Set_Raises_Constraint_Error (N);
547 Error_Msg_N ("Sub-aggregate high bound mismatch?", N);
548 Error_Msg_N ("Constraint_Error will be raised at run-time?",
554 if Dim < Aggr_Dimension then
556 -- Process positional components
558 if Present (Expressions (N)) then
559 Expr := First (Expressions (N));
560 while Present (Expr) loop
561 Collect_Aggr_Bounds (Expr, Dim + 1);
566 -- Process component associations
568 if Present (Component_Associations (N)) then
569 Is_Fully_Positional := False;
571 Assoc := First (Component_Associations (N));
572 while Present (Assoc) loop
573 Expr := Expression (Assoc);
574 Collect_Aggr_Bounds (Expr, Dim + 1);
579 end Collect_Aggr_Bounds;
581 -- Array_Aggr_Subtype variables
584 -- the final itype of the overall aggregate
586 Index_Constraints : constant List_Id := New_List;
587 -- The list of index constraints of the aggregate itype.
589 -- Start of processing for Array_Aggr_Subtype
592 -- Make sure that the list of index constraints is properly attached
593 -- to the tree, and then collect the aggregate bounds.
595 Set_Parent (Index_Constraints, N);
596 Collect_Aggr_Bounds (N, 1);
598 -- Build the list of constrained indices of our aggregate itype.
600 for J in 1 .. Aggr_Dimension loop
601 Create_Index : declare
602 Index_Base : constant Entity_Id :=
603 Base_Type (Etype (Aggr_Range (J)));
604 Index_Typ : Entity_Id;
607 -- Construct the Index subtype
609 Index_Typ := Create_Itype (Subtype_Kind (Ekind (Index_Base)), N);
611 Set_Etype (Index_Typ, Index_Base);
613 if Is_Character_Type (Index_Base) then
614 Set_Is_Character_Type (Index_Typ);
617 Set_Size_Info (Index_Typ, (Index_Base));
618 Set_RM_Size (Index_Typ, RM_Size (Index_Base));
619 Set_First_Rep_Item (Index_Typ, First_Rep_Item (Index_Base));
620 Set_Scalar_Range (Index_Typ, Aggr_Range (J));
622 if Is_Discrete_Or_Fixed_Point_Type (Index_Typ) then
623 Set_RM_Size (Index_Typ, UI_From_Int (Minimum_Size (Index_Typ)));
626 Set_Etype (Aggr_Range (J), Index_Typ);
628 Append (Aggr_Range (J), To => Index_Constraints);
632 -- Now build the Itype
634 Itype := Create_Itype (E_Array_Subtype, N);
636 Set_First_Rep_Item (Itype, First_Rep_Item (Typ));
637 Set_Convention (Itype, Convention (Typ));
638 Set_Depends_On_Private (Itype, Has_Private_Component (Typ));
639 Set_Etype (Itype, Base_Type (Typ));
640 Set_Has_Alignment_Clause (Itype, Has_Alignment_Clause (Typ));
641 Set_Is_Aliased (Itype, Is_Aliased (Typ));
642 Set_Depends_On_Private (Itype, Depends_On_Private (Typ));
644 Copy_Suppress_Status (Index_Check, Typ, Itype);
645 Copy_Suppress_Status (Length_Check, Typ, Itype);
647 Set_First_Index (Itype, First (Index_Constraints));
648 Set_Is_Constrained (Itype, True);
649 Set_Is_Internal (Itype, True);
650 Init_Size_Align (Itype);
652 -- A simple optimization: purely positional aggregates of static
653 -- components should be passed to gigi unexpanded whenever possible,
654 -- and regardless of the staticness of the bounds themselves. Subse-
655 -- quent checks in exp_aggr verify that type is not packed, etc.
657 Set_Size_Known_At_Compile_Time (Itype,
659 and then Comes_From_Source (N)
660 and then Size_Known_At_Compile_Time (Component_Type (Typ)));
662 -- We always need a freeze node for a packed array subtype, so that
663 -- we can build the Packed_Array_Type corresponding to the subtype.
664 -- If expansion is disabled, the packed array subtype is not built,
665 -- and we must not generate a freeze node for the type, or else it
666 -- will appear incomplete to gigi.
668 if Is_Packed (Itype) and then not In_Default_Expression
669 and then Expander_Active
671 Freeze_Itype (Itype, N);
675 end Array_Aggr_Subtype;
677 --------------------------------
678 -- Check_Misspelled_Component --
679 --------------------------------
681 procedure Check_Misspelled_Component
682 (Elements : Elist_Id;
685 Max_Suggestions : constant := 2;
687 Nr_Of_Suggestions : Natural := 0;
688 Suggestion_1 : Entity_Id := Empty;
689 Suggestion_2 : Entity_Id := Empty;
690 Component_Elmt : Elmt_Id;
693 -- All the components of List are matched against Component and
694 -- a count is maintained of possible misspellings. When at the
695 -- end of the analysis there are one or two (not more!) possible
696 -- misspellings, these misspellings will be suggested as
697 -- possible correction.
699 Get_Name_String (Chars (Component));
702 S : constant String (1 .. Name_Len) :=
703 Name_Buffer (1 .. Name_Len);
707 Component_Elmt := First_Elmt (Elements);
709 while Nr_Of_Suggestions <= Max_Suggestions
710 and then Present (Component_Elmt)
713 Get_Name_String (Chars (Node (Component_Elmt)));
715 if Is_Bad_Spelling_Of (Name_Buffer (1 .. Name_Len), S) then
716 Nr_Of_Suggestions := Nr_Of_Suggestions + 1;
718 case Nr_Of_Suggestions is
719 when 1 => Suggestion_1 := Node (Component_Elmt);
720 when 2 => Suggestion_2 := Node (Component_Elmt);
725 Next_Elmt (Component_Elmt);
728 -- Report at most two suggestions
730 if Nr_Of_Suggestions = 1 then
731 Error_Msg_NE ("\possible misspelling of&",
732 Component, Suggestion_1);
734 elsif Nr_Of_Suggestions = 2 then
735 Error_Msg_Node_2 := Suggestion_2;
736 Error_Msg_NE ("\possible misspelling of& or&",
737 Component, Suggestion_1);
740 end Check_Misspelled_Component;
742 ----------------------------------------
743 -- Check_Static_Discriminated_Subtype --
744 ----------------------------------------
746 procedure Check_Static_Discriminated_Subtype (T : Entity_Id; V : Node_Id) is
747 Disc : constant Entity_Id := First_Discriminant (T);
752 if Has_Record_Rep_Clause (T) then
755 elsif Present (Next_Discriminant (Disc)) then
758 elsif Nkind (V) /= N_Integer_Literal then
762 Comp := First_Component (T);
764 while Present (Comp) loop
766 if Is_Scalar_Type (Etype (Comp)) then
769 elsif Is_Private_Type (Etype (Comp))
770 and then Present (Full_View (Etype (Comp)))
771 and then Is_Scalar_Type (Full_View (Etype (Comp)))
775 elsif Is_Array_Type (Etype (Comp)) then
777 if Is_Bit_Packed_Array (Etype (Comp)) then
781 Ind := First_Index (Etype (Comp));
783 while Present (Ind) loop
785 if Nkind (Ind) /= N_Range
786 or else Nkind (Low_Bound (Ind)) /= N_Integer_Literal
787 or else Nkind (High_Bound (Ind)) /= N_Integer_Literal
799 Next_Component (Comp);
802 -- On exit, all components have statically known sizes.
804 Set_Size_Known_At_Compile_Time (T);
805 end Check_Static_Discriminated_Subtype;
807 --------------------------------
808 -- Make_String_Into_Aggregate --
809 --------------------------------
811 procedure Make_String_Into_Aggregate (N : Node_Id) is
812 Exprs : constant List_Id := New_List;
813 Loc : constant Source_Ptr := Sloc (N);
814 Str : constant String_Id := Strval (N);
815 Strlen : constant Nat := String_Length (Str);
823 for J in 1 .. Strlen loop
824 C := Get_String_Char (Str, J);
825 Set_Character_Literal_Name (C);
827 C_Node := Make_Character_Literal (P, Name_Find, C);
828 Set_Etype (C_Node, Any_Character);
829 Append_To (Exprs, C_Node);
832 -- something special for wide strings ???
835 New_N := Make_Aggregate (Loc, Expressions => Exprs);
836 Set_Analyzed (New_N);
837 Set_Etype (New_N, Any_Composite);
840 end Make_String_Into_Aggregate;
842 -----------------------
843 -- Resolve_Aggregate --
844 -----------------------
846 procedure Resolve_Aggregate (N : Node_Id; Typ : Entity_Id) is
847 Pkind : constant Node_Kind := Nkind (Parent (N));
849 Aggr_Subtyp : Entity_Id;
850 -- The actual aggregate subtype. This is not necessarily the same as Typ
851 -- which is the subtype of the context in which the aggregate was found.
854 -- Check for aggregates not allowed in configurable run-time mode.
855 -- We allow all cases of aggregates that do not come from source,
856 -- since these are all assumed to be small (e.g. bounds of a string
857 -- literal). We also allow aggregates of types we know to be small.
859 if not Support_Aggregates_On_Target
860 and then Comes_From_Source (N)
861 and then (not Known_Static_Esize (Typ) or else Esize (Typ) > 64)
863 Error_Msg_CRT ("aggregate", N);
866 if Is_Limited_Composite (Typ) then
867 Error_Msg_N ("aggregate type cannot have limited component", N);
868 Explain_Limited_Type (Typ, N);
870 -- Ada0Y (AI-287): Limited aggregates allowed
872 elsif Is_Limited_Type (Typ)
873 and not Extensions_Allowed
875 Error_Msg_N ("aggregate type cannot be limited", N);
876 Explain_Limited_Type (Typ, N);
878 elsif Is_Class_Wide_Type (Typ) then
879 Error_Msg_N ("type of aggregate cannot be class-wide", N);
881 elsif Typ = Any_String
882 or else Typ = Any_Composite
884 Error_Msg_N ("no unique type for aggregate", N);
885 Set_Etype (N, Any_Composite);
887 elsif Is_Array_Type (Typ) and then Null_Record_Present (N) then
888 Error_Msg_N ("null record forbidden in array aggregate", N);
890 elsif Is_Record_Type (Typ) then
891 Resolve_Record_Aggregate (N, Typ);
893 elsif Is_Array_Type (Typ) then
895 -- First a special test, for the case of a positional aggregate
896 -- of characters which can be replaced by a string literal.
897 -- Do not perform this transformation if this was a string literal
898 -- to start with, whose components needed constraint checks, or if
899 -- the component type is non-static, because it will require those
900 -- checks and be transformed back into an aggregate.
902 if Number_Dimensions (Typ) = 1
904 (Root_Type (Component_Type (Typ)) = Standard_Character
906 Root_Type (Component_Type (Typ)) = Standard_Wide_Character)
907 and then No (Component_Associations (N))
908 and then not Is_Limited_Composite (Typ)
909 and then not Is_Private_Composite (Typ)
910 and then not Is_Bit_Packed_Array (Typ)
911 and then Nkind (Original_Node (Parent (N))) /= N_String_Literal
912 and then Is_Static_Subtype (Component_Type (Typ))
918 Expr := First (Expressions (N));
919 while Present (Expr) loop
920 exit when Nkind (Expr) /= N_Character_Literal;
927 Expr := First (Expressions (N));
928 while Present (Expr) loop
929 Store_String_Char (Char_Literal_Value (Expr));
934 Make_String_Literal (Sloc (N), End_String));
936 Analyze_And_Resolve (N, Typ);
942 -- Here if we have a real aggregate to deal with
944 Array_Aggregate : declare
945 Aggr_Resolved : Boolean;
947 Aggr_Typ : constant Entity_Id := Etype (Typ);
948 -- This is the unconstrained array type, which is the type
949 -- against which the aggregate is to be resoved. Typ itself
950 -- is the array type of the context which may not be the same
951 -- subtype as the subtype for the final aggregate.
954 -- In the following we determine whether an others choice is
955 -- allowed inside the array aggregate. The test checks the context
956 -- in which the array aggregate occurs. If the context does not
957 -- permit it, or the aggregate type is unconstrained, an others
958 -- choice is not allowed.
960 -- Note that there is no node for Explicit_Actual_Parameter.
961 -- To test for this context we therefore have to test for node
962 -- N_Parameter_Association which itself appears only if there is a
963 -- formal parameter. Consequently we also need to test for
964 -- N_Procedure_Call_Statement or N_Function_Call.
966 Set_Etype (N, Aggr_Typ); -- may be overridden later on.
968 if Is_Constrained (Typ) and then
969 (Pkind = N_Assignment_Statement or else
970 Pkind = N_Parameter_Association or else
971 Pkind = N_Function_Call or else
972 Pkind = N_Procedure_Call_Statement or else
973 Pkind = N_Generic_Association or else
974 Pkind = N_Formal_Object_Declaration or else
975 Pkind = N_Return_Statement or else
976 Pkind = N_Object_Declaration or else
977 Pkind = N_Component_Declaration or else
978 Pkind = N_Parameter_Specification or else
979 Pkind = N_Qualified_Expression or else
980 Pkind = N_Aggregate or else
981 Pkind = N_Extension_Aggregate or else
982 Pkind = N_Component_Association)
985 Resolve_Array_Aggregate
987 Index => First_Index (Aggr_Typ),
988 Index_Constr => First_Index (Typ),
989 Component_Typ => Component_Type (Typ),
990 Others_Allowed => True);
994 Resolve_Array_Aggregate
996 Index => First_Index (Aggr_Typ),
997 Index_Constr => First_Index (Aggr_Typ),
998 Component_Typ => Component_Type (Typ),
999 Others_Allowed => False);
1002 if not Aggr_Resolved then
1003 Aggr_Subtyp := Any_Composite;
1005 Aggr_Subtyp := Array_Aggr_Subtype (N, Typ);
1008 Set_Etype (N, Aggr_Subtyp);
1009 end Array_Aggregate;
1012 Error_Msg_N ("illegal context for aggregate", N);
1016 -- If we can determine statically that the evaluation of the
1017 -- aggregate raises Constraint_Error, then replace the
1018 -- aggregate with an N_Raise_Constraint_Error node, but set the
1019 -- Etype to the right aggregate subtype. Gigi needs this.
1021 if Raises_Constraint_Error (N) then
1022 Aggr_Subtyp := Etype (N);
1024 Make_Raise_Constraint_Error (Sloc (N),
1025 Reason => CE_Range_Check_Failed));
1026 Set_Raises_Constraint_Error (N);
1027 Set_Etype (N, Aggr_Subtyp);
1030 end Resolve_Aggregate;
1032 -----------------------------
1033 -- Resolve_Array_Aggregate --
1034 -----------------------------
1036 function Resolve_Array_Aggregate
1039 Index_Constr : Node_Id;
1040 Component_Typ : Entity_Id;
1041 Others_Allowed : Boolean)
1044 Loc : constant Source_Ptr := Sloc (N);
1046 Failure : constant Boolean := False;
1047 Success : constant Boolean := True;
1049 Index_Typ : constant Entity_Id := Etype (Index);
1050 Index_Typ_Low : constant Node_Id := Type_Low_Bound (Index_Typ);
1051 Index_Typ_High : constant Node_Id := Type_High_Bound (Index_Typ);
1052 -- The type of the index corresponding to the array sub-aggregate
1053 -- along with its low and upper bounds
1055 Index_Base : constant Entity_Id := Base_Type (Index_Typ);
1056 Index_Base_Low : constant Node_Id := Type_Low_Bound (Index_Base);
1057 Index_Base_High : constant Node_Id := Type_High_Bound (Index_Base);
1058 -- ditto for the base type
1060 function Add (Val : Uint; To : Node_Id) return Node_Id;
1061 -- Creates a new expression node where Val is added to expression To.
1062 -- Tries to constant fold whenever possible. To must be an already
1063 -- analyzed expression.
1065 procedure Check_Bound (BH : Node_Id; AH : in out Node_Id);
1066 -- Checks that AH (the upper bound of an array aggregate) is <= BH
1067 -- (the upper bound of the index base type). If the check fails a
1068 -- warning is emitted, the Raises_Constraint_Error Flag of N is set,
1069 -- and AH is replaced with a duplicate of BH.
1071 procedure Check_Bounds (L, H : Node_Id; AL, AH : Node_Id);
1072 -- Checks that range AL .. AH is compatible with range L .. H. Emits a
1073 -- warning if not and sets the Raises_Constraint_Error Flag in N.
1075 procedure Check_Length (L, H : Node_Id; Len : Uint);
1076 -- Checks that range L .. H contains at least Len elements. Emits a
1077 -- warning if not and sets the Raises_Constraint_Error Flag in N.
1079 function Dynamic_Or_Null_Range (L, H : Node_Id) return Boolean;
1080 -- Returns True if range L .. H is dynamic or null.
1082 procedure Get (Value : out Uint; From : Node_Id; OK : out Boolean);
1083 -- Given expression node From, this routine sets OK to False if it
1084 -- cannot statically evaluate From. Otherwise it stores this static
1085 -- value into Value.
1087 function Resolve_Aggr_Expr
1089 Single_Elmt : Boolean)
1091 -- Resolves aggregate expression Expr. Returs False if resolution
1092 -- fails. If Single_Elmt is set to False, the expression Expr may be
1093 -- used to initialize several array aggregate elements (this can
1094 -- happen for discrete choices such as "L .. H => Expr" or the others
1095 -- choice). In this event we do not resolve Expr unless expansion is
1096 -- disabled. To know why, see the DELAYED COMPONENT RESOLUTION
1103 function Add (Val : Uint; To : Node_Id) return Node_Id is
1109 if Raises_Constraint_Error (To) then
1113 -- First test if we can do constant folding
1115 if Compile_Time_Known_Value (To)
1116 or else Nkind (To) = N_Integer_Literal
1118 Expr_Pos := Make_Integer_Literal (Loc, Expr_Value (To) + Val);
1119 Set_Is_Static_Expression (Expr_Pos);
1120 Set_Etype (Expr_Pos, Etype (To));
1121 Set_Analyzed (Expr_Pos, Analyzed (To));
1123 if not Is_Enumeration_Type (Index_Typ) then
1126 -- If we are dealing with enumeration return
1127 -- Index_Typ'Val (Expr_Pos)
1131 Make_Attribute_Reference
1133 Prefix => New_Reference_To (Index_Typ, Loc),
1134 Attribute_Name => Name_Val,
1135 Expressions => New_List (Expr_Pos));
1141 -- If we are here no constant folding possible
1143 if not Is_Enumeration_Type (Index_Base) then
1146 Left_Opnd => Duplicate_Subexpr (To),
1147 Right_Opnd => Make_Integer_Literal (Loc, Val));
1149 -- If we are dealing with enumeration return
1150 -- Index_Typ'Val (Index_Typ'Pos (To) + Val)
1154 Make_Attribute_Reference
1156 Prefix => New_Reference_To (Index_Typ, Loc),
1157 Attribute_Name => Name_Pos,
1158 Expressions => New_List (Duplicate_Subexpr (To)));
1162 Left_Opnd => To_Pos,
1163 Right_Opnd => Make_Integer_Literal (Loc, Val));
1166 Make_Attribute_Reference
1168 Prefix => New_Reference_To (Index_Typ, Loc),
1169 Attribute_Name => Name_Val,
1170 Expressions => New_List (Expr_Pos));
1180 procedure Check_Bound (BH : Node_Id; AH : in out Node_Id) is
1188 Get (Value => Val_BH, From => BH, OK => OK_BH);
1189 Get (Value => Val_AH, From => AH, OK => OK_AH);
1191 if OK_BH and then OK_AH and then Val_BH < Val_AH then
1192 Set_Raises_Constraint_Error (N);
1193 Error_Msg_N ("upper bound out of range?", AH);
1194 Error_Msg_N ("Constraint_Error will be raised at run-time?", AH);
1196 -- You need to set AH to BH or else in the case of enumerations
1197 -- indices we will not be able to resolve the aggregate bounds.
1199 AH := Duplicate_Subexpr (BH);
1207 procedure Check_Bounds (L, H : Node_Id; AL, AH : Node_Id) is
1219 if Raises_Constraint_Error (N)
1220 or else Dynamic_Or_Null_Range (AL, AH)
1225 Get (Value => Val_L, From => L, OK => OK_L);
1226 Get (Value => Val_H, From => H, OK => OK_H);
1228 Get (Value => Val_AL, From => AL, OK => OK_AL);
1229 Get (Value => Val_AH, From => AH, OK => OK_AH);
1231 if OK_L and then Val_L > Val_AL then
1232 Set_Raises_Constraint_Error (N);
1233 Error_Msg_N ("lower bound of aggregate out of range?", N);
1234 Error_Msg_N ("\Constraint_Error will be raised at run-time?", N);
1237 if OK_H and then Val_H < Val_AH then
1238 Set_Raises_Constraint_Error (N);
1239 Error_Msg_N ("upper bound of aggregate out of range?", N);
1240 Error_Msg_N ("\Constraint_Error will be raised at run-time?", N);
1248 procedure Check_Length (L, H : Node_Id; Len : Uint) is
1258 if Raises_Constraint_Error (N) then
1262 Get (Value => Val_L, From => L, OK => OK_L);
1263 Get (Value => Val_H, From => H, OK => OK_H);
1265 if not OK_L or else not OK_H then
1269 -- If null range length is zero
1271 if Val_L > Val_H then
1272 Range_Len := Uint_0;
1274 Range_Len := Val_H - Val_L + 1;
1277 if Range_Len < Len then
1278 Set_Raises_Constraint_Error (N);
1279 Error_Msg_N ("Too many elements?", N);
1280 Error_Msg_N ("Constraint_Error will be raised at run-time?", N);
1284 ---------------------------
1285 -- Dynamic_Or_Null_Range --
1286 ---------------------------
1288 function Dynamic_Or_Null_Range (L, H : Node_Id) return Boolean is
1296 Get (Value => Val_L, From => L, OK => OK_L);
1297 Get (Value => Val_H, From => H, OK => OK_H);
1299 return not OK_L or else not OK_H
1300 or else not Is_OK_Static_Expression (L)
1301 or else not Is_OK_Static_Expression (H)
1302 or else Val_L > Val_H;
1303 end Dynamic_Or_Null_Range;
1309 procedure Get (Value : out Uint; From : Node_Id; OK : out Boolean) is
1313 if Compile_Time_Known_Value (From) then
1314 Value := Expr_Value (From);
1316 -- If expression From is something like Some_Type'Val (10) then
1319 elsif Nkind (From) = N_Attribute_Reference
1320 and then Attribute_Name (From) = Name_Val
1321 and then Compile_Time_Known_Value (First (Expressions (From)))
1323 Value := Expr_Value (First (Expressions (From)));
1331 -----------------------
1332 -- Resolve_Aggr_Expr --
1333 -----------------------
1335 function Resolve_Aggr_Expr
1337 Single_Elmt : Boolean)
1340 Nxt_Ind : constant Node_Id := Next_Index (Index);
1341 Nxt_Ind_Constr : constant Node_Id := Next_Index (Index_Constr);
1342 -- Index is the current index corresponding to the expresion.
1344 Resolution_OK : Boolean := True;
1345 -- Set to False if resolution of the expression failed.
1348 -- If the array type against which we are resolving the aggregate
1349 -- has several dimensions, the expressions nested inside the
1350 -- aggregate must be further aggregates (or strings).
1352 if Present (Nxt_Ind) then
1353 if Nkind (Expr) /= N_Aggregate then
1355 -- A string literal can appear where a one-dimensional array
1356 -- of characters is expected. If the literal looks like an
1357 -- operator, it is still an operator symbol, which will be
1358 -- transformed into a string when analyzed.
1360 if Is_Character_Type (Component_Typ)
1361 and then No (Next_Index (Nxt_Ind))
1362 and then (Nkind (Expr) = N_String_Literal
1363 or else Nkind (Expr) = N_Operator_Symbol)
1365 -- A string literal used in a multidimensional array
1366 -- aggregate in place of the final one-dimensional
1367 -- aggregate must not be enclosed in parentheses.
1369 if Paren_Count (Expr) /= 0 then
1370 Error_Msg_N ("No parenthesis allowed here", Expr);
1373 Make_String_Into_Aggregate (Expr);
1376 Error_Msg_N ("nested array aggregate expected", Expr);
1381 Resolution_OK := Resolve_Array_Aggregate
1382 (Expr, Nxt_Ind, Nxt_Ind_Constr, Component_Typ, Others_Allowed);
1384 -- Do not resolve the expressions of discrete or others choices
1385 -- unless the expression covers a single component, or the expander
1389 or else not Expander_Active
1390 or else In_Default_Expression
1392 Analyze_And_Resolve (Expr, Component_Typ);
1393 Check_Non_Static_Context (Expr);
1394 Aggregate_Constraint_Checks (Expr, Component_Typ);
1395 Check_Unset_Reference (Expr);
1398 if Raises_Constraint_Error (Expr)
1399 and then Nkind (Parent (Expr)) /= N_Component_Association
1401 Set_Raises_Constraint_Error (N);
1404 return Resolution_OK;
1405 end Resolve_Aggr_Expr;
1407 -- Variables local to Resolve_Array_Aggregate
1413 Who_Cares : Node_Id;
1415 Aggr_Low : Node_Id := Empty;
1416 Aggr_High : Node_Id := Empty;
1417 -- The actual low and high bounds of this sub-aggegate
1419 Choices_Low : Node_Id := Empty;
1420 Choices_High : Node_Id := Empty;
1421 -- The lowest and highest discrete choices values for a named aggregate
1423 Nb_Elements : Uint := Uint_0;
1424 -- The number of elements in a positional aggegate
1426 Others_Present : Boolean := False;
1428 Nb_Choices : Nat := 0;
1429 -- Contains the overall number of named choices in this sub-aggregate
1431 Nb_Discrete_Choices : Nat := 0;
1432 -- The overall number of discrete choices (not counting others choice)
1434 Case_Table_Size : Nat;
1435 -- Contains the size of the case table needed to sort aggregate choices
1437 -- Start of processing for Resolve_Array_Aggregate
1440 -- STEP 1: make sure the aggregate is correctly formatted
1442 if Present (Component_Associations (N)) then
1443 Assoc := First (Component_Associations (N));
1444 while Present (Assoc) loop
1445 Choice := First (Choices (Assoc));
1446 while Present (Choice) loop
1447 if Nkind (Choice) = N_Others_Choice then
1448 Others_Present := True;
1450 if Choice /= First (Choices (Assoc))
1451 or else Present (Next (Choice))
1454 ("OTHERS must appear alone in a choice list", Choice);
1458 if Present (Next (Assoc)) then
1460 ("OTHERS must appear last in an aggregate", Choice);
1465 and then Assoc /= First (Component_Associations (N))
1466 and then (Nkind (Parent (N)) = N_Assignment_Statement
1468 Nkind (Parent (N)) = N_Object_Declaration)
1471 ("(Ada 83) illegal context for OTHERS choice", N);
1475 Nb_Choices := Nb_Choices + 1;
1483 -- At this point we know that the others choice, if present, is by
1484 -- itself and appears last in the aggregate. Check if we have mixed
1485 -- positional and discrete associations (other than the others choice).
1487 if Present (Expressions (N))
1488 and then (Nb_Choices > 1
1489 or else (Nb_Choices = 1 and then not Others_Present))
1492 ("named association cannot follow positional association",
1493 First (Choices (First (Component_Associations (N)))));
1497 -- Test for the validity of an others choice if present
1499 if Others_Present and then not Others_Allowed then
1501 ("OTHERS choice not allowed here",
1502 First (Choices (First (Component_Associations (N)))));
1506 -- Protect against cascaded errors
1508 if Etype (Index_Typ) = Any_Type then
1512 -- STEP 2: Process named components
1514 if No (Expressions (N)) then
1516 if Others_Present then
1517 Case_Table_Size := Nb_Choices - 1;
1519 Case_Table_Size := Nb_Choices;
1525 -- Denote the lowest and highest values in an aggregate choice
1529 -- High end of one range and Low end of the next. Should be
1530 -- contiguous if there is no hole in the list of values.
1532 Missing_Values : Boolean;
1533 -- Set True if missing index values
1535 S_Low : Node_Id := Empty;
1536 S_High : Node_Id := Empty;
1537 -- if a choice in an aggregate is a subtype indication these
1538 -- denote the lowest and highest values of the subtype
1540 Table : Case_Table_Type (1 .. Case_Table_Size);
1541 -- Used to sort all the different choice values
1543 Single_Choice : Boolean;
1544 -- Set to true every time there is a single discrete choice in a
1545 -- discrete association
1547 Prev_Nb_Discrete_Choices : Nat;
1548 -- Used to keep track of the number of discrete choices
1549 -- in the current association.
1552 -- STEP 2 (A): Check discrete choices validity.
1554 Assoc := First (Component_Associations (N));
1555 while Present (Assoc) loop
1557 Prev_Nb_Discrete_Choices := Nb_Discrete_Choices;
1558 Choice := First (Choices (Assoc));
1562 if Nkind (Choice) = N_Others_Choice then
1563 Single_Choice := False;
1566 -- Test for subtype mark without constraint
1568 elsif Is_Entity_Name (Choice) and then
1569 Is_Type (Entity (Choice))
1571 if Base_Type (Entity (Choice)) /= Index_Base then
1573 ("invalid subtype mark in aggregate choice",
1578 elsif Nkind (Choice) = N_Subtype_Indication then
1579 Resolve_Discrete_Subtype_Indication (Choice, Index_Base);
1581 -- Does the subtype indication evaluation raise CE ?
1583 Get_Index_Bounds (Subtype_Mark (Choice), S_Low, S_High);
1584 Get_Index_Bounds (Choice, Low, High);
1585 Check_Bounds (S_Low, S_High, Low, High);
1587 else -- Choice is a range or an expression
1588 Resolve (Choice, Index_Base);
1589 Check_Unset_Reference (Choice);
1590 Check_Non_Static_Context (Choice);
1592 -- Do not range check a choice. This check is redundant
1593 -- since this test is already performed when we check
1594 -- that the bounds of the array aggregate are within
1597 Set_Do_Range_Check (Choice, False);
1600 -- If we could not resolve the discrete choice stop here
1602 if Etype (Choice) = Any_Type then
1605 -- If the discrete choice raises CE get its original bounds.
1607 elsif Nkind (Choice) = N_Raise_Constraint_Error then
1608 Set_Raises_Constraint_Error (N);
1609 Get_Index_Bounds (Original_Node (Choice), Low, High);
1611 -- Otherwise get its bounds as usual
1614 Get_Index_Bounds (Choice, Low, High);
1617 if (Dynamic_Or_Null_Range (Low, High)
1618 or else (Nkind (Choice) = N_Subtype_Indication
1620 Dynamic_Or_Null_Range (S_Low, S_High)))
1621 and then Nb_Choices /= 1
1624 ("dynamic or empty choice in aggregate " &
1625 "must be the only choice", Choice);
1629 Nb_Discrete_Choices := Nb_Discrete_Choices + 1;
1630 Table (Nb_Discrete_Choices).Choice_Lo := Low;
1631 Table (Nb_Discrete_Choices).Choice_Hi := High;
1636 -- Check if we have a single discrete choice and whether
1637 -- this discrete choice specifies a single value.
1640 (Nb_Discrete_Choices = Prev_Nb_Discrete_Choices + 1)
1641 and then (Low = High);
1647 -- Ada0Y (AI-287): In case of default initialized component
1648 -- we delay the resolution to the expansion phase
1650 if Box_Present (Assoc) then
1652 -- Ada0Y (AI-287): In case of default initialization of a
1653 -- component the expander will generate calls to the
1654 -- corresponding initialization subprogram.
1656 if Present (Base_Init_Proc (Etype (Component_Typ)))
1657 or else Has_Task (Base_Type (Component_Typ))
1662 ("(Ada 0Y): no value supplied for this component",
1666 elsif not Resolve_Aggr_Expr (Expression (Assoc),
1667 Single_Elmt => Single_Choice)
1675 -- If aggregate contains more than one choice then these must be
1676 -- static. Sort them and check that they are contiguous
1678 if Nb_Discrete_Choices > 1 then
1679 Sort_Case_Table (Table);
1680 Missing_Values := False;
1682 Outer : for J in 1 .. Nb_Discrete_Choices - 1 loop
1683 if Expr_Value (Table (J).Choice_Hi) >=
1684 Expr_Value (Table (J + 1).Choice_Lo)
1687 ("duplicate choice values in array aggregate",
1688 Table (J).Choice_Hi);
1691 elsif not Others_Present then
1693 Hi_Val := Expr_Value (Table (J).Choice_Hi);
1694 Lo_Val := Expr_Value (Table (J + 1).Choice_Lo);
1696 -- If missing values, output error messages
1698 if Lo_Val - Hi_Val > 1 then
1700 -- Header message if not first missing value
1702 if not Missing_Values then
1704 ("missing index value(s) in array aggregate", N);
1705 Missing_Values := True;
1708 -- Output values of missing indexes
1710 Lo_Val := Lo_Val - 1;
1711 Hi_Val := Hi_Val + 1;
1713 -- Enumeration type case
1715 if Is_Enumeration_Type (Index_Typ) then
1718 (Get_Enum_Lit_From_Pos
1719 (Index_Typ, Hi_Val, Loc));
1721 if Lo_Val = Hi_Val then
1722 Error_Msg_N ("\ %", N);
1726 (Get_Enum_Lit_From_Pos
1727 (Index_Typ, Lo_Val, Loc));
1728 Error_Msg_N ("\ % .. %", N);
1731 -- Integer types case
1734 Error_Msg_Uint_1 := Hi_Val;
1736 if Lo_Val = Hi_Val then
1737 Error_Msg_N ("\ ^", N);
1739 Error_Msg_Uint_2 := Lo_Val;
1740 Error_Msg_N ("\ ^ .. ^", N);
1747 if Missing_Values then
1748 Set_Etype (N, Any_Composite);
1753 -- STEP 2 (B): Compute aggregate bounds and min/max choices values
1755 if Nb_Discrete_Choices > 0 then
1756 Choices_Low := Table (1).Choice_Lo;
1757 Choices_High := Table (Nb_Discrete_Choices).Choice_Hi;
1760 if Others_Present then
1761 Get_Index_Bounds (Index_Constr, Aggr_Low, Aggr_High);
1764 Aggr_Low := Choices_Low;
1765 Aggr_High := Choices_High;
1769 -- STEP 3: Process positional components
1772 -- STEP 3 (A): Process positional elements
1774 Expr := First (Expressions (N));
1775 Nb_Elements := Uint_0;
1776 while Present (Expr) loop
1777 Nb_Elements := Nb_Elements + 1;
1779 if not Resolve_Aggr_Expr (Expr, Single_Elmt => True) then
1786 if Others_Present then
1787 Assoc := Last (Component_Associations (N));
1789 -- Ada0Y (AI-287): In case of default initialized component
1790 -- we delay the resolution to the expansion phase.
1792 if Box_Present (Assoc) then
1794 -- Ada0Y (AI-287): In case of default initialization of a
1795 -- component the expander will generate calls to the
1796 -- corresponding initialization subprogram.
1798 if Present (Base_Init_Proc (Etype (Component_Typ))) then
1802 ("(Ada 0Y): no value supplied for these components",
1806 elsif not Resolve_Aggr_Expr (Expression (Assoc),
1807 Single_Elmt => False)
1813 -- STEP 3 (B): Compute the aggregate bounds
1815 if Others_Present then
1816 Get_Index_Bounds (Index_Constr, Aggr_Low, Aggr_High);
1819 if Others_Allowed then
1820 Get_Index_Bounds (Index_Constr, Aggr_Low, Who_Cares);
1822 Aggr_Low := Index_Typ_Low;
1825 Aggr_High := Add (Nb_Elements - 1, To => Aggr_Low);
1826 Check_Bound (Index_Base_High, Aggr_High);
1830 -- STEP 4: Perform static aggregate checks and save the bounds
1834 Check_Bounds (Index_Typ_Low, Index_Typ_High, Aggr_Low, Aggr_High);
1835 Check_Bounds (Index_Base_Low, Index_Base_High, Aggr_Low, Aggr_High);
1839 if Others_Present and then Nb_Discrete_Choices > 0 then
1840 Check_Bounds (Aggr_Low, Aggr_High, Choices_Low, Choices_High);
1841 Check_Bounds (Index_Typ_Low, Index_Typ_High,
1842 Choices_Low, Choices_High);
1843 Check_Bounds (Index_Base_Low, Index_Base_High,
1844 Choices_Low, Choices_High);
1848 elsif Others_Present and then Nb_Elements > 0 then
1849 Check_Length (Aggr_Low, Aggr_High, Nb_Elements);
1850 Check_Length (Index_Typ_Low, Index_Typ_High, Nb_Elements);
1851 Check_Length (Index_Base_Low, Index_Base_High, Nb_Elements);
1855 if Raises_Constraint_Error (Aggr_Low)
1856 or else Raises_Constraint_Error (Aggr_High)
1858 Set_Raises_Constraint_Error (N);
1861 Aggr_Low := Duplicate_Subexpr (Aggr_Low);
1863 -- Do not duplicate Aggr_High if Aggr_High = Aggr_Low + Nb_Elements
1864 -- since the addition node returned by Add is not yet analyzed. Attach
1865 -- to tree and analyze first. Reset analyzed flag to insure it will get
1866 -- analyzed when it is a literal bound whose type must be properly
1869 if Others_Present or else Nb_Discrete_Choices > 0 then
1870 Aggr_High := Duplicate_Subexpr (Aggr_High);
1872 if Etype (Aggr_High) = Universal_Integer then
1873 Set_Analyzed (Aggr_High, False);
1877 Set_Aggregate_Bounds
1878 (N, Make_Range (Loc, Low_Bound => Aggr_Low, High_Bound => Aggr_High));
1880 -- The bounds may contain expressions that must be inserted upwards.
1881 -- Attach them fully to the tree. After analysis, remove side effects
1882 -- from upper bound, if still needed.
1884 Set_Parent (Aggregate_Bounds (N), N);
1885 Analyze_And_Resolve (Aggregate_Bounds (N), Index_Typ);
1886 Check_Unset_Reference (Aggregate_Bounds (N));
1888 if not Others_Present and then Nb_Discrete_Choices = 0 then
1889 Set_High_Bound (Aggregate_Bounds (N),
1890 Duplicate_Subexpr (High_Bound (Aggregate_Bounds (N))));
1894 end Resolve_Array_Aggregate;
1896 ---------------------------------
1897 -- Resolve_Extension_Aggregate --
1898 ---------------------------------
1900 -- There are two cases to consider:
1902 -- a) If the ancestor part is a type mark, the components needed are
1903 -- the difference between the components of the expected type and the
1904 -- components of the given type mark.
1906 -- b) If the ancestor part is an expression, it must be unambiguous,
1907 -- and once we have its type we can also compute the needed components
1908 -- as in the previous case. In both cases, if the ancestor type is not
1909 -- the immediate ancestor, we have to build this ancestor recursively.
1911 -- In both cases discriminants of the ancestor type do not play a
1912 -- role in the resolution of the needed components, because inherited
1913 -- discriminants cannot be used in a type extension. As a result we can
1914 -- compute independently the list of components of the ancestor type and
1915 -- of the expected type.
1917 procedure Resolve_Extension_Aggregate (N : Node_Id; Typ : Entity_Id) is
1918 A : constant Node_Id := Ancestor_Part (N);
1923 function Valid_Ancestor_Type return Boolean;
1924 -- Verify that the type of the ancestor part is a non-private ancestor
1925 -- of the expected type.
1927 -------------------------
1928 -- Valid_Ancestor_Type --
1929 -------------------------
1931 function Valid_Ancestor_Type return Boolean is
1932 Imm_Type : Entity_Id;
1935 Imm_Type := Base_Type (Typ);
1936 while Is_Derived_Type (Imm_Type)
1937 and then Etype (Imm_Type) /= Base_Type (A_Type)
1939 Imm_Type := Etype (Base_Type (Imm_Type));
1942 if Etype (Imm_Type) /= Base_Type (A_Type) then
1943 Error_Msg_NE ("expect ancestor type of &", A, Typ);
1948 end Valid_Ancestor_Type;
1950 -- Start of processing for Resolve_Extension_Aggregate
1955 if not Is_Tagged_Type (Typ) then
1956 Error_Msg_N ("type of extension aggregate must be tagged", N);
1959 elsif Is_Limited_Type (Typ) then
1961 -- Ada0Y (AI-287): Limited aggregates are allowed
1963 if Extensions_Allowed then
1966 Error_Msg_N ("aggregate type cannot be limited", N);
1967 Explain_Limited_Type (Typ, N);
1971 elsif Is_Class_Wide_Type (Typ) then
1972 Error_Msg_N ("aggregate cannot be of a class-wide type", N);
1976 if Is_Entity_Name (A)
1977 and then Is_Type (Entity (A))
1979 A_Type := Get_Full_View (Entity (A));
1981 if Valid_Ancestor_Type then
1982 Set_Entity (A, A_Type);
1983 Set_Etype (A, A_Type);
1985 Validate_Ancestor_Part (N);
1986 Resolve_Record_Aggregate (N, Typ);
1989 elsif Nkind (A) /= N_Aggregate then
1990 if Is_Overloaded (A) then
1992 Get_First_Interp (A, I, It);
1994 while Present (It.Typ) loop
1996 if Is_Tagged_Type (It.Typ)
1997 and then not Is_Limited_Type (It.Typ)
1999 if A_Type /= Any_Type then
2000 Error_Msg_N ("cannot resolve expression", A);
2007 Get_Next_Interp (I, It);
2010 if A_Type = Any_Type then
2012 ("ancestor part must be non-limited tagged type", A);
2017 A_Type := Etype (A);
2020 if Valid_Ancestor_Type then
2021 Resolve (A, A_Type);
2022 Check_Unset_Reference (A);
2023 Check_Non_Static_Context (A);
2025 if Is_Class_Wide_Type (Etype (A))
2026 and then Nkind (Original_Node (A)) = N_Function_Call
2028 -- If the ancestor part is a dispatching call, it appears
2029 -- statically to be a legal ancestor, but it yields any
2030 -- member of the class, and it is not possible to determine
2031 -- whether it is an ancestor of the extension aggregate (much
2032 -- less which ancestor). It is not possible to determine the
2033 -- required components of the extension part.
2035 Error_Msg_N ("ancestor part must be statically tagged", A);
2037 Resolve_Record_Aggregate (N, Typ);
2042 Error_Msg_N (" No unique type for this aggregate", A);
2044 end Resolve_Extension_Aggregate;
2046 ------------------------------
2047 -- Resolve_Record_Aggregate --
2048 ------------------------------
2050 procedure Resolve_Record_Aggregate (N : Node_Id; Typ : Entity_Id) is
2051 New_Assoc_List : constant List_Id := New_List;
2052 New_Assoc : Node_Id;
2053 -- New_Assoc_List is the newly built list of N_Component_Association
2054 -- nodes. New_Assoc is one such N_Component_Association node in it.
2055 -- Please note that while Assoc and New_Assoc contain the same
2056 -- kind of nodes, they are used to iterate over two different
2057 -- N_Component_Association lists.
2059 Others_Etype : Entity_Id := Empty;
2060 -- This variable is used to save the Etype of the last record component
2061 -- that takes its value from the others choice. Its purpose is:
2063 -- (a) make sure the others choice is useful
2065 -- (b) make sure the type of all the components whose value is
2066 -- subsumed by the others choice are the same.
2068 -- This variable is updated as a side effect of function Get_Value
2070 Mbox_Present : Boolean := False;
2071 Others_Mbox : Boolean := False;
2072 -- Ada0Y (AI-287): Variables used in case of default initialization to
2073 -- provide a functionality similar to Others_Etype. Mbox_Present
2074 -- indicates that the component takes its default initialization;
2075 -- Others_Mbox indicates that at least one component takes its default
2076 -- initialization. Similar to Others_Etype, they are also updated as a
2077 -- side effect of function Get_Value.
2079 procedure Add_Association
2080 (Component : Entity_Id;
2082 Box_Present : Boolean := False);
2083 -- Builds a new N_Component_Association node which associates
2084 -- Component to expression Expr and adds it to the new association
2085 -- list New_Assoc_List being built.
2087 function Discr_Present (Discr : Entity_Id) return Boolean;
2088 -- If aggregate N is a regular aggregate this routine will return True.
2089 -- Otherwise, if N is an extension aggregate, Discr is a discriminant
2090 -- whose value may already have been specified by N's ancestor part,
2091 -- this routine checks whether this is indeed the case and if so
2092 -- returns False, signaling that no value for Discr should appear in the
2093 -- N's aggregate part. Also, in this case, the routine appends to
2094 -- New_Assoc_List Discr the discriminant value specified in the ancestor
2100 Consider_Others_Choice : Boolean := False)
2102 -- Given a record component stored in parameter Compon, the
2103 -- following function returns its value as it appears in the list
2104 -- From, which is a list of N_Component_Association nodes. If no
2105 -- component association has a choice for the searched component,
2106 -- the value provided by the others choice is returned, if there
2107 -- is one and Consider_Others_Choice is set to true. Otherwise
2108 -- Empty is returned. If there is more than one component association
2109 -- giving a value for the searched record component, an error message
2110 -- is emitted and the first found value is returned.
2112 -- If Consider_Others_Choice is set and the returned expression comes
2113 -- from the others choice, then Others_Etype is set as a side effect.
2114 -- An error message is emitted if the components taking their value
2115 -- from the others choice do not have same type.
2117 procedure Resolve_Aggr_Expr (Expr : Node_Id; Component : Node_Id);
2118 -- Analyzes and resolves expression Expr against the Etype of the
2119 -- Component. This routine also applies all appropriate checks to Expr.
2120 -- It finally saves a Expr in the newly created association list that
2121 -- will be attached to the final record aggregate. Note that if the
2122 -- Parent pointer of Expr is not set then Expr was produced with a
2123 -- New_Copy_Tree or some such.
2125 ---------------------
2126 -- Add_Association --
2127 ---------------------
2129 procedure Add_Association
2130 (Component : Entity_Id;
2132 Box_Present : Boolean := False)
2134 Choice_List : constant List_Id := New_List;
2135 New_Assoc : Node_Id;
2138 Append (New_Occurrence_Of (Component, Sloc (Expr)), Choice_List);
2140 Make_Component_Association (Sloc (Expr),
2141 Choices => Choice_List,
2143 Box_Present => Box_Present);
2144 Append (New_Assoc, New_Assoc_List);
2145 end Add_Association;
2151 function Discr_Present (Discr : Entity_Id) return Boolean is
2152 Regular_Aggr : constant Boolean := Nkind (N) /= N_Extension_Aggregate;
2157 Discr_Expr : Node_Id;
2159 Ancestor_Typ : Entity_Id;
2160 Orig_Discr : Entity_Id;
2162 D_Val : Elmt_Id := No_Elmt; -- stop junk warning
2164 Ancestor_Is_Subtyp : Boolean;
2167 if Regular_Aggr then
2171 Ancestor := Ancestor_Part (N);
2172 Ancestor_Typ := Etype (Ancestor);
2173 Loc := Sloc (Ancestor);
2175 Ancestor_Is_Subtyp :=
2176 Is_Entity_Name (Ancestor) and then Is_Type (Entity (Ancestor));
2178 -- If the ancestor part has no discriminants clearly N's aggregate
2179 -- part must provide a value for Discr.
2181 if not Has_Discriminants (Ancestor_Typ) then
2184 -- If the ancestor part is an unconstrained subtype mark then the
2185 -- Discr must be present in N's aggregate part.
2187 elsif Ancestor_Is_Subtyp
2188 and then not Is_Constrained (Entity (Ancestor))
2193 -- Now look to see if Discr was specified in the ancestor part.
2195 Orig_Discr := Original_Record_Component (Discr);
2196 D := First_Discriminant (Ancestor_Typ);
2198 if Ancestor_Is_Subtyp then
2199 D_Val := First_Elmt (Discriminant_Constraint (Entity (Ancestor)));
2202 while Present (D) loop
2203 -- If Ancestor has already specified Disc value than
2204 -- insert its value in the final aggregate.
2206 if Original_Record_Component (D) = Orig_Discr then
2207 if Ancestor_Is_Subtyp then
2208 Discr_Expr := New_Copy_Tree (Node (D_Val));
2211 Make_Selected_Component (Loc,
2212 Prefix => Duplicate_Subexpr (Ancestor),
2213 Selector_Name => New_Occurrence_Of (Discr, Loc));
2216 Resolve_Aggr_Expr (Discr_Expr, Discr);
2220 Next_Discriminant (D);
2222 if Ancestor_Is_Subtyp then
2237 Consider_Others_Choice : Boolean := False)
2241 Expr : Node_Id := Empty;
2242 Selector_Name : Node_Id;
2244 procedure Check_Non_Limited_Type;
2245 -- Relax check to allow the default initialization of limited types.
2248 -- C : Lim := (..., others => <>);
2251 ----------------------------
2252 -- Check_Non_Limited_Type --
2253 ----------------------------
2255 procedure Check_Non_Limited_Type is
2257 if Is_Limited_Type (Etype (Compon))
2258 and then Comes_From_Source (Compon)
2259 and then not In_Instance_Body
2261 -- Ada0Y (AI-287): Limited aggregates are allowed
2263 if Extensions_Allowed
2264 and then Present (Expression (Assoc))
2265 and then Nkind (Expression (Assoc)) = N_Aggregate
2270 ("initialization not allowed for limited types", N);
2271 Explain_Limited_Type (Etype (Compon), Compon);
2275 end Check_Non_Limited_Type;
2277 -- Start of processing for Get_Value
2280 Mbox_Present := False;
2282 if Present (From) then
2283 Assoc := First (From);
2288 while Present (Assoc) loop
2289 Selector_Name := First (Choices (Assoc));
2290 while Present (Selector_Name) loop
2291 if Nkind (Selector_Name) = N_Others_Choice then
2292 if Consider_Others_Choice and then No (Expr) then
2294 -- We need to duplicate the expression for each
2295 -- successive component covered by the others choice.
2296 -- This is redundant if the others_choice covers only
2297 -- one component (small optimization possible???), but
2298 -- indispensable otherwise, because each one must be
2299 -- expanded individually to preserve side-effects.
2301 -- Ada0Y (AI-287): In case of default initialization of
2302 -- components, we duplicate the corresponding default
2303 -- expression (from the record type declaration).
2305 if Box_Present (Assoc) then
2306 Others_Mbox := True;
2307 Mbox_Present := True;
2309 if Expander_Active then
2310 return New_Copy_Tree (Expression (Parent (Compon)));
2312 return Expression (Parent (Compon));
2316 Check_Non_Limited_Type;
2318 if Present (Others_Etype) and then
2319 Base_Type (Others_Etype) /= Base_Type (Etype
2322 Error_Msg_N ("components in OTHERS choice must " &
2323 "have same type", Selector_Name);
2326 Others_Etype := Etype (Compon);
2328 if Expander_Active then
2329 return New_Copy_Tree (Expression (Assoc));
2331 return Expression (Assoc);
2336 elsif Chars (Compon) = Chars (Selector_Name) then
2339 -- We need to duplicate the expression when several
2340 -- components are grouped together with a "|" choice.
2341 -- For instance "filed1 | filed2 => Expr"
2343 if Box_Present (Assoc) then
2344 Mbox_Present := True;
2346 -- Duplicate the default expression of the component
2347 -- from the record type declaration
2349 if Present (Next (Selector_Name)) then
2350 Expr := New_Copy_Tree
2351 (Expression (Parent (Compon)));
2353 Expr := Expression (Parent (Compon));
2357 Check_Non_Limited_Type;
2359 if Present (Next (Selector_Name)) then
2360 Expr := New_Copy_Tree (Expression (Assoc));
2362 Expr := Expression (Assoc);
2366 Generate_Reference (Compon, Selector_Name);
2370 ("more than one value supplied for &",
2371 Selector_Name, Compon);
2376 Next (Selector_Name);
2385 -----------------------
2386 -- Resolve_Aggr_Expr --
2387 -----------------------
2389 procedure Resolve_Aggr_Expr (Expr : Node_Id; Component : Node_Id) is
2390 New_C : Entity_Id := Component;
2391 Expr_Type : Entity_Id := Empty;
2393 function Has_Expansion_Delayed (Expr : Node_Id) return Boolean;
2394 -- If the expression is an aggregate (possibly qualified) then its
2395 -- expansion is delayed until the enclosing aggregate is expanded
2396 -- into assignments. In that case, do not generate checks on the
2397 -- expression, because they will be generated later, and will other-
2398 -- wise force a copy (to remove side-effects) that would leave a
2399 -- dynamic-sized aggregate in the code, something that gigi cannot
2403 -- Set to True if the resolved Expr node needs to be relocated
2404 -- when attached to the newly created association list. This node
2405 -- need not be relocated if its parent pointer is not set.
2406 -- In fact in this case Expr is the output of a New_Copy_Tree call.
2407 -- if Relocate is True then we have analyzed the expression node
2408 -- in the original aggregate and hence it needs to be relocated
2409 -- when moved over the new association list.
2411 function Has_Expansion_Delayed (Expr : Node_Id) return Boolean is
2412 Kind : constant Node_Kind := Nkind (Expr);
2415 return ((Kind = N_Aggregate
2416 or else Kind = N_Extension_Aggregate)
2417 and then Present (Etype (Expr))
2418 and then Is_Record_Type (Etype (Expr))
2419 and then Expansion_Delayed (Expr))
2421 or else (Kind = N_Qualified_Expression
2422 and then Has_Expansion_Delayed (Expression (Expr)));
2423 end Has_Expansion_Delayed;
2425 -- Start of processing for Resolve_Aggr_Expr
2428 -- If the type of the component is elementary or the type of the
2429 -- aggregate does not contain discriminants, use the type of the
2430 -- component to resolve Expr.
2432 if Is_Elementary_Type (Etype (Component))
2433 or else not Has_Discriminants (Etype (N))
2435 Expr_Type := Etype (Component);
2437 -- Otherwise we have to pick up the new type of the component from
2438 -- the new costrained subtype of the aggregate. In fact components
2439 -- which are of a composite type might be constrained by a
2440 -- discriminant, and we want to resolve Expr against the subtype were
2441 -- all discriminant occurrences are replaced with their actual value.
2444 New_C := First_Component (Etype (N));
2445 while Present (New_C) loop
2446 if Chars (New_C) = Chars (Component) then
2447 Expr_Type := Etype (New_C);
2451 Next_Component (New_C);
2454 pragma Assert (Present (Expr_Type));
2456 -- For each range in an array type where a discriminant has been
2457 -- replaced with the constraint, check that this range is within
2458 -- the range of the base type. This checks is done in the
2459 -- init proc for regular objects, but has to be done here for
2460 -- aggregates since no init proc is called for them.
2462 if Is_Array_Type (Expr_Type) then
2464 Index : Node_Id := First_Index (Expr_Type);
2465 -- Range of the current constrained index in the array.
2467 Orig_Index : Node_Id := First_Index (Etype (Component));
2468 -- Range corresponding to the range Index above in the
2469 -- original unconstrained record type. The bounds of this
2470 -- range may be governed by discriminants.
2472 Unconstr_Index : Node_Id := First_Index (Etype (Expr_Type));
2473 -- Range corresponding to the range Index above for the
2474 -- unconstrained array type. This range is needed to apply
2478 while Present (Index) loop
2479 if Depends_On_Discriminant (Orig_Index) then
2480 Apply_Range_Check (Index, Etype (Unconstr_Index));
2484 Next_Index (Orig_Index);
2485 Next_Index (Unconstr_Index);
2491 -- If the Parent pointer of Expr is not set, Expr is an expression
2492 -- duplicated by New_Tree_Copy (this happens for record aggregates
2493 -- that look like (Field1 | Filed2 => Expr) or (others => Expr)).
2494 -- Such a duplicated expression must be attached to the tree
2495 -- before analysis and resolution to enforce the rule that a tree
2496 -- fragment should never be analyzed or resolved unless it is
2497 -- attached to the current compilation unit.
2499 if No (Parent (Expr)) then
2500 Set_Parent (Expr, N);
2506 Analyze_And_Resolve (Expr, Expr_Type);
2507 Check_Non_Static_Context (Expr);
2508 Check_Unset_Reference (Expr);
2510 if not Has_Expansion_Delayed (Expr) then
2511 Aggregate_Constraint_Checks (Expr, Expr_Type);
2514 if Raises_Constraint_Error (Expr) then
2515 Set_Raises_Constraint_Error (N);
2519 Add_Association (New_C, Relocate_Node (Expr));
2521 Add_Association (New_C, Expr);
2523 end Resolve_Aggr_Expr;
2525 -- Resolve_Record_Aggregate local variables
2528 -- N_Component_Association node belonging to the input aggregate N
2531 Positional_Expr : Node_Id;
2532 Component : Entity_Id;
2533 Component_Elmt : Elmt_Id;
2535 Components : constant Elist_Id := New_Elmt_List;
2536 -- Components is the list of the record components whose value must
2537 -- be provided in the aggregate. This list does include discriminants.
2539 -- Start of processing for Resolve_Record_Aggregate
2542 -- We may end up calling Duplicate_Subexpr on expressions that are
2543 -- attached to New_Assoc_List. For this reason we need to attach it
2544 -- to the tree by setting its parent pointer to N. This parent point
2545 -- will change in STEP 8 below.
2547 Set_Parent (New_Assoc_List, N);
2549 -- STEP 1: abstract type and null record verification
2551 if Is_Abstract (Typ) then
2552 Error_Msg_N ("type of aggregate cannot be abstract", N);
2555 if No (First_Entity (Typ)) and then Null_Record_Present (N) then
2559 elsif Present (First_Entity (Typ))
2560 and then Null_Record_Present (N)
2561 and then not Is_Tagged_Type (Typ)
2563 Error_Msg_N ("record aggregate cannot be null", N);
2566 elsif No (First_Entity (Typ)) then
2567 Error_Msg_N ("record aggregate must be null", N);
2571 -- STEP 2: Verify aggregate structure
2574 Selector_Name : Node_Id;
2575 Bad_Aggregate : Boolean := False;
2578 if Present (Component_Associations (N)) then
2579 Assoc := First (Component_Associations (N));
2584 while Present (Assoc) loop
2585 Selector_Name := First (Choices (Assoc));
2586 while Present (Selector_Name) loop
2587 if Nkind (Selector_Name) = N_Identifier then
2590 elsif Nkind (Selector_Name) = N_Others_Choice then
2591 if Selector_Name /= First (Choices (Assoc))
2592 or else Present (Next (Selector_Name))
2594 Error_Msg_N ("OTHERS must appear alone in a choice list",
2598 elsif Present (Next (Assoc)) then
2599 Error_Msg_N ("OTHERS must appear last in an aggregate",
2606 ("selector name should be identifier or OTHERS",
2608 Bad_Aggregate := True;
2611 Next (Selector_Name);
2617 if Bad_Aggregate then
2622 -- STEP 3: Find discriminant Values
2625 Discrim : Entity_Id;
2626 Missing_Discriminants : Boolean := False;
2629 if Present (Expressions (N)) then
2630 Positional_Expr := First (Expressions (N));
2632 Positional_Expr := Empty;
2635 if Has_Discriminants (Typ) then
2636 Discrim := First_Discriminant (Typ);
2641 -- First find the discriminant values in the positional components
2643 while Present (Discrim) and then Present (Positional_Expr) loop
2644 if Discr_Present (Discrim) then
2645 Resolve_Aggr_Expr (Positional_Expr, Discrim);
2646 Next (Positional_Expr);
2649 if Present (Get_Value (Discrim, Component_Associations (N))) then
2651 ("more than one value supplied for discriminant&",
2655 Next_Discriminant (Discrim);
2658 -- Find remaining discriminant values, if any, among named components
2660 while Present (Discrim) loop
2661 Expr := Get_Value (Discrim, Component_Associations (N), True);
2663 if not Discr_Present (Discrim) then
2664 if Present (Expr) then
2666 ("more than one value supplied for discriminant&",
2670 elsif No (Expr) then
2672 ("no value supplied for discriminant &", N, Discrim);
2673 Missing_Discriminants := True;
2676 Resolve_Aggr_Expr (Expr, Discrim);
2679 Next_Discriminant (Discrim);
2682 if Missing_Discriminants then
2686 -- At this point and until the beginning of STEP 6, New_Assoc_List
2687 -- contains only the discriminants and their values.
2691 -- STEP 4: Set the Etype of the record aggregate
2693 -- ??? This code is pretty much a copy of Sem_Ch3.Build_Subtype. That
2694 -- routine should really be exported in sem_util or some such and used
2695 -- in sem_ch3 and here rather than have a copy of the code which is a
2696 -- maintenance nightmare.
2698 -- ??? Performace WARNING. The current implementation creates a new
2699 -- itype for all aggregates whose base type is discriminated.
2700 -- This means that for record aggregates nested inside an array
2701 -- aggregate we will create a new itype for each record aggregate
2702 -- if the array cmponent type has discriminants. For large aggregates
2703 -- this may be a problem. What should be done in this case is
2704 -- to reuse itypes as much as possible.
2706 if Has_Discriminants (Typ) then
2707 Build_Constrained_Itype : declare
2708 Loc : constant Source_Ptr := Sloc (N);
2710 Subtyp_Decl : Node_Id;
2713 C : constant List_Id := New_List;
2716 New_Assoc := First (New_Assoc_List);
2717 while Present (New_Assoc) loop
2718 Append (Duplicate_Subexpr (Expression (New_Assoc)), To => C);
2723 Make_Subtype_Indication (Loc,
2724 Subtype_Mark => New_Occurrence_Of (Base_Type (Typ), Loc),
2725 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
2727 Def_Id := Create_Itype (Ekind (Typ), N);
2730 Make_Subtype_Declaration (Loc,
2731 Defining_Identifier => Def_Id,
2732 Subtype_Indication => Indic);
2733 Set_Parent (Subtyp_Decl, Parent (N));
2735 -- Itypes must be analyzed with checks off (see itypes.ads).
2737 Analyze (Subtyp_Decl, Suppress => All_Checks);
2739 Set_Etype (N, Def_Id);
2740 Check_Static_Discriminated_Subtype
2741 (Def_Id, Expression (First (New_Assoc_List)));
2742 end Build_Constrained_Itype;
2748 -- STEP 5: Get remaining components according to discriminant values
2751 Record_Def : Node_Id;
2752 Parent_Typ : Entity_Id;
2753 Root_Typ : Entity_Id;
2754 Parent_Typ_List : Elist_Id;
2755 Parent_Elmt : Elmt_Id;
2756 Errors_Found : Boolean := False;
2760 if Is_Derived_Type (Typ) and then Is_Tagged_Type (Typ) then
2761 Parent_Typ_List := New_Elmt_List;
2763 -- If this is an extension aggregate, the component list must
2764 -- include all components that are not in the given ancestor
2765 -- type. Otherwise, the component list must include components
2766 -- of all ancestors, starting with the root.
2768 if Nkind (N) = N_Extension_Aggregate then
2769 Root_Typ := Base_Type (Etype (Ancestor_Part (N)));
2771 Root_Typ := Root_Type (Typ);
2773 if Nkind (Parent (Base_Type (Root_Typ)))
2774 = N_Private_Type_Declaration
2777 ("type of aggregate has private ancestor&!",
2779 Error_Msg_N ("must use extension aggregate!", N);
2783 Dnode := Declaration_Node (Base_Type (Root_Typ));
2785 -- If we don't get a full declaration, then we have some
2786 -- error which will get signalled later so skip this part.
2787 -- Otherwise, gather components of root that apply to the
2788 -- aggregate type. We use the base type in case there is an
2789 -- applicable stored constraint that renames the discriminants
2792 if Nkind (Dnode) = N_Full_Type_Declaration then
2793 Record_Def := Type_Definition (Dnode);
2794 Gather_Components (Base_Type (Typ),
2795 Component_List (Record_Def),
2796 Governed_By => New_Assoc_List,
2798 Report_Errors => Errors_Found);
2802 Parent_Typ := Base_Type (Typ);
2803 while Parent_Typ /= Root_Typ loop
2805 Prepend_Elmt (Parent_Typ, To => Parent_Typ_List);
2806 Parent_Typ := Etype (Parent_Typ);
2808 if Nkind (Parent (Base_Type (Parent_Typ))) =
2809 N_Private_Type_Declaration
2810 or else Nkind (Parent (Base_Type (Parent_Typ))) =
2811 N_Private_Extension_Declaration
2813 if Nkind (N) /= N_Extension_Aggregate then
2815 ("type of aggregate has private ancestor&!",
2817 Error_Msg_N ("must use extension aggregate!", N);
2820 elsif Parent_Typ /= Root_Typ then
2822 ("ancestor part of aggregate must be private type&",
2823 Ancestor_Part (N), Parent_Typ);
2829 -- Now collect components from all other ancestors.
2831 Parent_Elmt := First_Elmt (Parent_Typ_List);
2832 while Present (Parent_Elmt) loop
2833 Parent_Typ := Node (Parent_Elmt);
2834 Record_Def := Type_Definition (Parent (Base_Type (Parent_Typ)));
2835 Gather_Components (Empty,
2836 Component_List (Record_Extension_Part (Record_Def)),
2837 Governed_By => New_Assoc_List,
2839 Report_Errors => Errors_Found);
2841 Next_Elmt (Parent_Elmt);
2845 Record_Def := Type_Definition (Parent (Base_Type (Typ)));
2847 if Null_Present (Record_Def) then
2850 Gather_Components (Base_Type (Typ),
2851 Component_List (Record_Def),
2852 Governed_By => New_Assoc_List,
2854 Report_Errors => Errors_Found);
2858 if Errors_Found then
2863 -- STEP 6: Find component Values
2866 Component_Elmt := First_Elmt (Components);
2868 -- First scan the remaining positional associations in the aggregate.
2869 -- Remember that at this point Positional_Expr contains the current
2870 -- positional association if any is left after looking for discriminant
2871 -- values in step 3.
2873 while Present (Positional_Expr) and then Present (Component_Elmt) loop
2874 Component := Node (Component_Elmt);
2875 Resolve_Aggr_Expr (Positional_Expr, Component);
2877 if Present (Get_Value (Component, Component_Associations (N))) then
2879 ("more than one value supplied for Component &", N, Component);
2882 Next (Positional_Expr);
2883 Next_Elmt (Component_Elmt);
2886 if Present (Positional_Expr) then
2888 ("too many components for record aggregate", Positional_Expr);
2891 -- Now scan for the named arguments of the aggregate
2893 while Present (Component_Elmt) loop
2894 Component := Node (Component_Elmt);
2895 Expr := Get_Value (Component, Component_Associations (N), True);
2897 if Mbox_Present and then Is_Limited_Type (Etype (Component)) then
2899 -- Ada0Y (AI-287): In case of default initialization of a limited
2900 -- component we pass the limited component to the expander. The
2901 -- expander will generate calls to the corresponding initiali-
2902 -- zation subprograms.
2905 (Component => Component,
2907 Box_Present => True);
2909 elsif No (Expr) then
2910 Error_Msg_NE ("no value supplied for component &!", N, Component);
2912 Resolve_Aggr_Expr (Expr, Component);
2915 Next_Elmt (Component_Elmt);
2918 -- STEP 7: check for invalid components + check type in choice list
2925 -- Type of first component in choice list
2928 if Present (Component_Associations (N)) then
2929 Assoc := First (Component_Associations (N));
2934 Verification : while Present (Assoc) loop
2935 Selectr := First (Choices (Assoc));
2938 if Nkind (Selectr) = N_Others_Choice then
2940 -- Ada0Y (AI-287): others choice may have expression or mbox
2942 if No (Others_Etype)
2943 and then not Others_Mbox
2946 ("OTHERS must represent at least one component", Selectr);
2952 while Present (Selectr) loop
2953 New_Assoc := First (New_Assoc_List);
2954 while Present (New_Assoc) loop
2955 Component := First (Choices (New_Assoc));
2956 exit when Chars (Selectr) = Chars (Component);
2960 -- If no association, this is not a legal component of
2961 -- of the type in question, except if this is an internal
2962 -- component supplied by a previous expansion.
2964 if No (New_Assoc) then
2965 if Box_Present (Parent (Selectr)) then
2968 elsif Chars (Selectr) /= Name_uTag
2969 and then Chars (Selectr) /= Name_uParent
2970 and then Chars (Selectr) /= Name_uController
2972 if not Has_Discriminants (Typ) then
2973 Error_Msg_Node_2 := Typ;
2975 ("& is not a component of}",
2979 ("& is not a component of the aggregate subtype",
2983 Check_Misspelled_Component (Components, Selectr);
2986 elsif No (Typech) then
2987 Typech := Base_Type (Etype (Component));
2989 elsif Typech /= Base_Type (Etype (Component)) then
2990 if not Box_Present (Parent (Selectr)) then
2992 ("components in choice list must have same type",
3001 end loop Verification;
3004 -- STEP 8: replace the original aggregate
3007 New_Aggregate : constant Node_Id := New_Copy (N);
3010 Set_Expressions (New_Aggregate, No_List);
3011 Set_Etype (New_Aggregate, Etype (N));
3012 Set_Component_Associations (New_Aggregate, New_Assoc_List);
3014 Rewrite (N, New_Aggregate);
3016 end Resolve_Record_Aggregate;
3018 ---------------------
3019 -- Sort_Case_Table --
3020 ---------------------
3022 procedure Sort_Case_Table (Case_Table : in out Case_Table_Type) is
3023 L : constant Int := Case_Table'First;
3024 U : constant Int := Case_Table'Last;
3033 T := Case_Table (K + 1);
3037 and then Expr_Value (Case_Table (J - 1).Choice_Lo) >
3038 Expr_Value (T.Choice_Lo)
3040 Case_Table (J) := Case_Table (J - 1);
3044 Case_Table (J) := T;
3047 end Sort_Case_Table;
OSDN Git Service
