1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2007, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree
; use Atree
;
27 with Checks
; use Checks
;
28 with Einfo
; use Einfo
;
29 with Elists
; use Elists
;
30 with Errout
; use Errout
;
31 with Exp_Tss
; use Exp_Tss
;
32 with Exp_Util
; use Exp_Util
;
33 with Freeze
; use Freeze
;
34 with Itypes
; use Itypes
;
36 with Lib
.Xref
; use Lib
.Xref
;
37 with Namet
; use Namet
;
38 with Namet
.Sp
; use Namet
.Sp
;
39 with Nmake
; use Nmake
;
40 with Nlists
; use Nlists
;
43 with Sem_Cat
; use Sem_Cat
;
44 with Sem_Ch3
; use Sem_Ch3
;
45 with Sem_Ch13
; use Sem_Ch13
;
46 with Sem_Eval
; use Sem_Eval
;
47 with Sem_Res
; use Sem_Res
;
48 with Sem_Util
; use Sem_Util
;
49 with Sem_Type
; use Sem_Type
;
50 with Sem_Warn
; use Sem_Warn
;
51 with Sinfo
; use Sinfo
;
52 with Snames
; use Snames
;
53 with Stringt
; use Stringt
;
54 with Stand
; use Stand
;
55 with Targparm
; use Targparm
;
56 with Tbuild
; use Tbuild
;
57 with Uintp
; use Uintp
;
59 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
(Typ
: Entity_Id
; Expr
: Node_Id
);
81 -- Ada 2005 (AI-231): Check bad usage of null for a component for which
82 -- null exclusion (NOT NULL) is specified. Typ can be an E_Array_Type for
83 -- the array case (the component type of the array will be used) or an
84 -- E_Component/E_Discriminant entity in the record case, in which case the
85 -- type of the component will be used for the test. If Typ is any other
86 -- kind of entity, the call is ignored. Expr is the component node in the
87 -- aggregate which is known to have a null value. A warning message will be
88 -- issued if the component is null excluding.
90 -- It would be better to pass the proper type for Typ ???
92 ------------------------------------------------------
93 -- Subprograms used for RECORD AGGREGATE Processing --
94 ------------------------------------------------------
96 procedure Resolve_Record_Aggregate
(N
: Node_Id
; Typ
: Entity_Id
);
97 -- This procedure performs all the semantic checks required for record
98 -- aggregates. Note that for aggregates analysis and resolution go
99 -- hand in hand. Aggregate analysis has been delayed up to here and
100 -- it is done while resolving the aggregate.
102 -- N is the N_Aggregate node.
103 -- Typ is the record type for the aggregate resolution
105 -- While performing the semantic checks, this procedure builds a new
106 -- Component_Association_List where each record field appears alone in a
107 -- Component_Choice_List along with its corresponding expression. The
108 -- record fields in the Component_Association_List appear in the same order
109 -- in which they appear in the record type Typ.
111 -- Once this new Component_Association_List is built and all the semantic
112 -- checks performed, the original aggregate subtree is replaced with the
113 -- new named record aggregate just built. Note that subtree substitution is
114 -- performed with Rewrite so as to be able to retrieve the original
117 -- The aggregate subtree manipulation performed by Resolve_Record_Aggregate
118 -- yields the aggregate format expected by Gigi. Typically, this kind of
119 -- tree manipulations are done in the expander. However, because the
120 -- semantic checks that need to be performed on record aggregates really go
121 -- hand in hand with the record aggregate normalization, the aggregate
122 -- subtree transformation is performed during resolution rather than
123 -- expansion. Had we decided otherwise we would have had to duplicate most
124 -- of the code in the expansion procedure Expand_Record_Aggregate. Note,
125 -- however, that all the expansion concerning aggregates for tagged records
126 -- is done in Expand_Record_Aggregate.
128 -- The algorithm of Resolve_Record_Aggregate proceeds as follows:
130 -- 1. Make sure that the record type against which the record aggregate
131 -- has to be resolved is not abstract. Furthermore if the type is
132 -- a null aggregate make sure the input aggregate N is also null.
134 -- 2. Verify that the structure of the aggregate is that of a record
135 -- aggregate. Specifically, look for component associations and ensure
136 -- that each choice list only has identifiers or the N_Others_Choice
137 -- node. Also make sure that if present, the N_Others_Choice occurs
138 -- last and by itself.
140 -- 3. If Typ contains discriminants, the values for each discriminant
141 -- is looked for. If the record type Typ has variants, we check
142 -- that the expressions corresponding to each discriminant ruling
143 -- the (possibly nested) variant parts of Typ, are static. This
144 -- allows us to determine the variant parts to which the rest of
145 -- the aggregate must conform. The names of discriminants with their
146 -- values are saved in a new association list, New_Assoc_List which
147 -- is later augmented with the names and values of the remaining
148 -- components in the record type.
150 -- During this phase we also make sure that every discriminant is
151 -- assigned exactly one value. Note that when several values
152 -- for a given discriminant are found, semantic processing continues
153 -- looking for further errors. In this case it's the first
154 -- discriminant value found which we will be recorded.
156 -- IMPORTANT NOTE: For derived tagged types this procedure expects
157 -- First_Discriminant and Next_Discriminant to give the correct list
158 -- of discriminants, in the correct order.
160 -- 4. After all the discriminant values have been gathered, we can
161 -- set the Etype of the record aggregate. If Typ contains no
162 -- discriminants this is straightforward: the Etype of N is just
163 -- Typ, otherwise a new implicit constrained subtype of Typ is
164 -- built to be the Etype of N.
166 -- 5. Gather the remaining record components according to the discriminant
167 -- values. This involves recursively traversing the record type
168 -- structure to see what variants are selected by the given discriminant
169 -- values. This processing is a little more convoluted if Typ is a
170 -- derived tagged types since we need to retrieve the record structure
171 -- of all the ancestors of Typ.
173 -- 6. After gathering the record components we look for their values
174 -- in the record aggregate and emit appropriate error messages
175 -- should we not find such values or should they be duplicated.
177 -- 7. We then make sure no illegal component names appear in the
178 -- record aggregate and make sure that the type of the record
179 -- components appearing in a same choice list is the same.
180 -- Finally we ensure that the others choice, if present, is
181 -- used to provide the value of at least a record component.
183 -- 8. The original aggregate node is replaced with the new named
184 -- aggregate built in steps 3 through 6, as explained earlier.
186 -- Given the complexity of record aggregate resolution, the primary
187 -- goal of this routine is clarity and simplicity rather than execution
188 -- and storage efficiency. If there are only positional components in the
189 -- aggregate the running time is linear. If there are associations
190 -- the running time is still linear as long as the order of the
191 -- associations is not too far off the order of the components in the
192 -- record type. If this is not the case the running time is at worst
193 -- quadratic in the size of the association list.
195 procedure Check_Misspelled_Component
196 (Elements
: Elist_Id
;
197 Component
: Node_Id
);
198 -- Give possible misspelling diagnostic if Component is likely to be
199 -- a misspelling of one of the components of the Assoc_List.
200 -- This is called by Resolv_Aggr_Expr after producing
201 -- an invalid component error message.
203 procedure Check_Static_Discriminated_Subtype
(T
: Entity_Id
; V
: Node_Id
);
204 -- An optimization: determine whether a discriminated subtype has a
205 -- static constraint, and contains array components whose length is also
206 -- static, either because they are constrained by the discriminant, or
207 -- because the original component bounds are static.
209 -----------------------------------------------------
210 -- Subprograms used for ARRAY AGGREGATE Processing --
211 -----------------------------------------------------
213 function Resolve_Array_Aggregate
216 Index_Constr
: Node_Id
;
217 Component_Typ
: Entity_Id
;
218 Others_Allowed
: Boolean)
220 -- This procedure performs the semantic checks for an array aggregate.
221 -- True is returned if the aggregate resolution succeeds.
222 -- The procedure works by recursively checking each nested aggregate.
223 -- Specifically, after checking a sub-aggregate nested at the i-th level
224 -- we recursively check all the subaggregates at the i+1-st level (if any).
225 -- Note that for aggregates analysis and resolution go hand in hand.
226 -- Aggregate analysis has been delayed up to here and it is done while
227 -- resolving the aggregate.
229 -- N is the current N_Aggregate node to be checked.
231 -- Index is the index node corresponding to the array sub-aggregate that
232 -- we are currently checking (RM 4.3.3 (8)). Its Etype is the
233 -- corresponding index type (or subtype).
235 -- Index_Constr is the node giving the applicable index constraint if
236 -- any (RM 4.3.3 (10)). It "is a constraint provided by certain
237 -- contexts [...] that can be used to determine the bounds of the array
238 -- value specified by the aggregate". If Others_Allowed below is False
239 -- there is no applicable index constraint and this node is set to Index.
241 -- Component_Typ is the array component type.
243 -- Others_Allowed indicates whether an others choice is allowed
244 -- in the context where the top-level aggregate appeared.
246 -- The algorithm of Resolve_Array_Aggregate proceeds as follows:
248 -- 1. Make sure that the others choice, if present, is by itself and
249 -- appears last in the sub-aggregate. Check that we do not have
250 -- positional and named components in the array sub-aggregate (unless
251 -- the named association is an others choice). Finally if an others
252 -- choice is present, make sure it is allowed in the aggregate contex.
254 -- 2. If the array sub-aggregate contains discrete_choices:
256 -- (A) Verify their validity. Specifically verify that:
258 -- (a) If a null range is present it must be the only possible
259 -- choice in the array aggregate.
261 -- (b) Ditto for a non static range.
263 -- (c) Ditto for a non static expression.
265 -- In addition this step analyzes and resolves each discrete_choice,
266 -- making sure that its type is the type of the corresponding Index.
267 -- If we are not at the lowest array aggregate level (in the case of
268 -- multi-dimensional aggregates) then invoke Resolve_Array_Aggregate
269 -- recursively on each component expression. Otherwise, resolve the
270 -- bottom level component expressions against the expected component
271 -- type ONLY IF the component corresponds to a single discrete choice
272 -- which is not an others choice (to see why read the DELAYED
273 -- COMPONENT RESOLUTION below).
275 -- (B) Determine the bounds of the sub-aggregate and lowest and
276 -- highest choice values.
278 -- 3. For positional aggregates:
280 -- (A) Loop over the component expressions either recursively invoking
281 -- Resolve_Array_Aggregate on each of these for multi-dimensional
282 -- array aggregates or resolving the bottom level component
283 -- expressions against the expected component type.
285 -- (B) Determine the bounds of the positional sub-aggregates.
287 -- 4. Try to determine statically whether the evaluation of the array
288 -- sub-aggregate raises Constraint_Error. If yes emit proper
289 -- warnings. The precise checks are the following:
291 -- (A) Check that the index range defined by aggregate bounds is
292 -- compatible with corresponding index subtype.
293 -- We also check against the base type. In fact it could be that
294 -- Low/High bounds of the base type are static whereas those of
295 -- the index subtype are not. Thus if we can statically catch
296 -- a problem with respect to the base type we are guaranteed
297 -- that the same problem will arise with the index subtype
299 -- (B) If we are dealing with a named aggregate containing an others
300 -- choice and at least one discrete choice then make sure the range
301 -- specified by the discrete choices does not overflow the
302 -- aggregate bounds. We also check against the index type and base
303 -- type bounds for the same reasons given in (A).
305 -- (C) If we are dealing with a positional aggregate with an others
306 -- choice make sure the number of positional elements specified
307 -- does not overflow the aggregate bounds. We also check against
308 -- the index type and base type bounds as mentioned in (A).
310 -- Finally construct an N_Range node giving the sub-aggregate bounds.
311 -- Set the Aggregate_Bounds field of the sub-aggregate to be this
312 -- N_Range. The routine Array_Aggr_Subtype below uses such N_Ranges
313 -- to build the appropriate aggregate subtype. Aggregate_Bounds
314 -- information is needed during expansion.
316 -- DELAYED COMPONENT RESOLUTION: The resolution of bottom level component
317 -- expressions in an array aggregate may call Duplicate_Subexpr or some
318 -- other routine that inserts code just outside the outermost aggregate.
319 -- If the array aggregate contains discrete choices or an others choice,
320 -- this may be wrong. Consider for instance the following example.
322 -- type Rec is record
326 -- type Acc_Rec is access Rec;
327 -- Arr : array (1..3) of Acc_Rec := (1 .. 3 => new Rec);
329 -- Then the transformation of "new Rec" that occurs during resolution
330 -- entails the following code modifications
332 -- P7b : constant Acc_Rec := new Rec;
334 -- Arr : array (1..3) of Acc_Rec := (1 .. 3 => P7b);
336 -- This code transformation is clearly wrong, since we need to call
337 -- "new Rec" for each of the 3 array elements. To avoid this problem we
338 -- delay resolution of the components of non positional array aggregates
339 -- to the expansion phase. As an optimization, if the discrete choice
340 -- specifies a single value we do not delay resolution.
342 function Array_Aggr_Subtype
(N
: Node_Id
; Typ
: Node_Id
) return Entity_Id
;
343 -- This routine returns the type or subtype of an array aggregate.
345 -- N is the array aggregate node whose type we return.
347 -- Typ is the context type in which N occurs.
349 -- This routine creates an implicit array subtype whose bounds are
350 -- those defined by the aggregate. When this routine is invoked
351 -- Resolve_Array_Aggregate has already processed aggregate N. Thus the
352 -- Aggregate_Bounds of each sub-aggregate, is an N_Range node giving the
353 -- sub-aggregate bounds. When building the aggregate itype, this function
354 -- traverses the array aggregate N collecting such Aggregate_Bounds and
355 -- constructs the proper array aggregate itype.
357 -- Note that in the case of multidimensional aggregates each inner
358 -- sub-aggregate corresponding to a given array dimension, may provide a
359 -- different bounds. If it is possible to determine statically that
360 -- some sub-aggregates corresponding to the same index do not have the
361 -- same bounds, then a warning is emitted. If such check is not possible
362 -- statically (because some sub-aggregate bounds are dynamic expressions)
363 -- then this job is left to the expander. In all cases the particular
364 -- bounds that this function will chose for a given dimension is the first
365 -- N_Range node for a sub-aggregate corresponding to that dimension.
367 -- Note that the Raises_Constraint_Error flag of an array aggregate
368 -- whose evaluation is determined to raise CE by Resolve_Array_Aggregate,
369 -- is set in Resolve_Array_Aggregate but the aggregate is not
370 -- immediately replaced with a raise CE. In fact, Array_Aggr_Subtype must
371 -- first construct the proper itype for the aggregate (Gigi needs
372 -- this). After constructing the proper itype we will eventually replace
373 -- the top-level aggregate with a raise CE (done in Resolve_Aggregate).
374 -- Of course in cases such as:
376 -- type Arr is array (integer range <>) of Integer;
377 -- A : Arr := (positive range -1 .. 2 => 0);
379 -- The bounds of the aggregate itype are cooked up to look reasonable
380 -- (in this particular case the bounds will be 1 .. 2).
382 procedure Aggregate_Constraint_Checks
384 Check_Typ
: Entity_Id
);
385 -- Checks expression Exp against subtype Check_Typ. If Exp is an
386 -- aggregate and Check_Typ a constrained record type with discriminants,
387 -- we generate the appropriate discriminant checks. If Exp is an array
388 -- aggregate then emit the appropriate length checks. If Exp is a scalar
389 -- type, or a string literal, Exp is changed into Check_Typ'(Exp) to
390 -- ensure that range checks are performed at run time.
392 procedure Make_String_Into_Aggregate
(N
: Node_Id
);
393 -- A string literal can appear in a context in which a one dimensional
394 -- array of characters is expected. This procedure simply rewrites the
395 -- string as an aggregate, prior to resolution.
397 ---------------------------------
398 -- Aggregate_Constraint_Checks --
399 ---------------------------------
401 procedure Aggregate_Constraint_Checks
403 Check_Typ
: Entity_Id
)
405 Exp_Typ
: constant Entity_Id
:= Etype
(Exp
);
408 if Raises_Constraint_Error
(Exp
) then
412 -- This is really expansion activity, so make sure that expansion
413 -- is on and is allowed.
415 if not Expander_Active
or else In_Default_Expression
then
419 -- First check if we have to insert discriminant checks
421 if Has_Discriminants
(Exp_Typ
) then
422 Apply_Discriminant_Check
(Exp
, Check_Typ
);
424 -- Next emit length checks for array aggregates
426 elsif Is_Array_Type
(Exp_Typ
) then
427 Apply_Length_Check
(Exp
, Check_Typ
);
429 -- Finally emit scalar and string checks. If we are dealing with a
430 -- scalar literal we need to check by hand because the Etype of
431 -- literals is not necessarily correct.
433 elsif Is_Scalar_Type
(Exp_Typ
)
434 and then Compile_Time_Known_Value
(Exp
)
436 if Is_Out_Of_Range
(Exp
, Base_Type
(Check_Typ
)) then
437 Apply_Compile_Time_Constraint_Error
438 (Exp
, "value not in range of}?", CE_Range_Check_Failed
,
439 Ent
=> Base_Type
(Check_Typ
),
440 Typ
=> Base_Type
(Check_Typ
));
442 elsif Is_Out_Of_Range
(Exp
, Check_Typ
) then
443 Apply_Compile_Time_Constraint_Error
444 (Exp
, "value not in range of}?", CE_Range_Check_Failed
,
448 elsif not Range_Checks_Suppressed
(Check_Typ
) then
449 Apply_Scalar_Range_Check
(Exp
, Check_Typ
);
452 -- Verify that target type is also scalar, to prevent view anomalies
453 -- in instantiations.
455 elsif (Is_Scalar_Type
(Exp_Typ
)
456 or else Nkind
(Exp
) = N_String_Literal
)
457 and then Is_Scalar_Type
(Check_Typ
)
458 and then Exp_Typ
/= Check_Typ
460 if Is_Entity_Name
(Exp
)
461 and then Ekind
(Entity
(Exp
)) = E_Constant
463 -- If expression is a constant, it is worthwhile checking whether
464 -- it is a bound of the type.
466 if (Is_Entity_Name
(Type_Low_Bound
(Check_Typ
))
467 and then Entity
(Exp
) = Entity
(Type_Low_Bound
(Check_Typ
)))
468 or else (Is_Entity_Name
(Type_High_Bound
(Check_Typ
))
469 and then Entity
(Exp
) = Entity
(Type_High_Bound
(Check_Typ
)))
474 Rewrite
(Exp
, Convert_To
(Check_Typ
, Relocate_Node
(Exp
)));
475 Analyze_And_Resolve
(Exp
, Check_Typ
);
476 Check_Unset_Reference
(Exp
);
479 Rewrite
(Exp
, Convert_To
(Check_Typ
, Relocate_Node
(Exp
)));
480 Analyze_And_Resolve
(Exp
, Check_Typ
);
481 Check_Unset_Reference
(Exp
);
484 -- Ada 2005 (AI-230): Generate a conversion to an anonymous access
485 -- component's type to force the appropriate accessibility checks.
487 -- Ada 2005 (AI-231): Generate conversion to the null-excluding
488 -- type to force the corresponding run-time check
490 elsif Is_Access_Type
(Check_Typ
)
491 and then ((Is_Local_Anonymous_Access
(Check_Typ
))
492 or else (Can_Never_Be_Null
(Check_Typ
)
493 and then not Can_Never_Be_Null
(Exp_Typ
)))
495 Rewrite
(Exp
, Convert_To
(Check_Typ
, Relocate_Node
(Exp
)));
496 Analyze_And_Resolve
(Exp
, Check_Typ
);
497 Check_Unset_Reference
(Exp
);
499 end Aggregate_Constraint_Checks
;
501 ------------------------
502 -- Array_Aggr_Subtype --
503 ------------------------
505 function Array_Aggr_Subtype
510 Aggr_Dimension
: constant Pos
:= Number_Dimensions
(Typ
);
511 -- Number of aggregate index dimensions
513 Aggr_Range
: array (1 .. Aggr_Dimension
) of Node_Id
:= (others => Empty
);
514 -- Constrained N_Range of each index dimension in our aggregate itype
516 Aggr_Low
: array (1 .. Aggr_Dimension
) of Node_Id
:= (others => Empty
);
517 Aggr_High
: array (1 .. Aggr_Dimension
) of Node_Id
:= (others => Empty
);
518 -- Low and High bounds for each index dimension in our aggregate itype
520 Is_Fully_Positional
: Boolean := True;
522 procedure Collect_Aggr_Bounds
(N
: Node_Id
; Dim
: Pos
);
523 -- N is an array (sub-)aggregate. Dim is the dimension corresponding to
524 -- (sub-)aggregate N. This procedure collects the constrained N_Range
525 -- nodes corresponding to each index dimension of our aggregate itype.
526 -- These N_Range nodes are collected in Aggr_Range above.
528 -- Likewise collect in Aggr_Low & Aggr_High above the low and high
529 -- bounds of each index dimension. If, when collecting, two bounds
530 -- corresponding to the same dimension are static and found to differ,
531 -- then emit a warning, and mark N as raising Constraint_Error.
533 -------------------------
534 -- Collect_Aggr_Bounds --
535 -------------------------
537 procedure Collect_Aggr_Bounds
(N
: Node_Id
; Dim
: Pos
) is
538 This_Range
: constant Node_Id
:= Aggregate_Bounds
(N
);
539 -- The aggregate range node of this specific sub-aggregate
541 This_Low
: constant Node_Id
:= Low_Bound
(Aggregate_Bounds
(N
));
542 This_High
: constant Node_Id
:= High_Bound
(Aggregate_Bounds
(N
));
543 -- The aggregate bounds of this specific sub-aggregate
549 -- Collect the first N_Range for a given dimension that you find.
550 -- For a given dimension they must be all equal anyway.
552 if No
(Aggr_Range
(Dim
)) then
553 Aggr_Low
(Dim
) := This_Low
;
554 Aggr_High
(Dim
) := This_High
;
555 Aggr_Range
(Dim
) := This_Range
;
558 if Compile_Time_Known_Value
(This_Low
) then
559 if not Compile_Time_Known_Value
(Aggr_Low
(Dim
)) then
560 Aggr_Low
(Dim
) := This_Low
;
562 elsif Expr_Value
(This_Low
) /= Expr_Value
(Aggr_Low
(Dim
)) then
563 Set_Raises_Constraint_Error
(N
);
564 Error_Msg_N
("sub-aggregate low bound mismatch?", N
);
566 ("\Constraint_Error will be raised at run-time?", N
);
570 if Compile_Time_Known_Value
(This_High
) then
571 if not Compile_Time_Known_Value
(Aggr_High
(Dim
)) then
572 Aggr_High
(Dim
) := This_High
;
575 Expr_Value
(This_High
) /= Expr_Value
(Aggr_High
(Dim
))
577 Set_Raises_Constraint_Error
(N
);
578 Error_Msg_N
("sub-aggregate high bound mismatch?", N
);
580 ("\Constraint_Error will be raised at run-time?", N
);
585 if Dim
< Aggr_Dimension
then
587 -- Process positional components
589 if Present
(Expressions
(N
)) then
590 Expr
:= First
(Expressions
(N
));
591 while Present
(Expr
) loop
592 Collect_Aggr_Bounds
(Expr
, Dim
+ 1);
597 -- Process component associations
599 if Present
(Component_Associations
(N
)) then
600 Is_Fully_Positional
:= False;
602 Assoc
:= First
(Component_Associations
(N
));
603 while Present
(Assoc
) loop
604 Expr
:= Expression
(Assoc
);
605 Collect_Aggr_Bounds
(Expr
, Dim
+ 1);
610 end Collect_Aggr_Bounds
;
612 -- Array_Aggr_Subtype variables
615 -- the final itype of the overall aggregate
617 Index_Constraints
: constant List_Id
:= New_List
;
618 -- The list of index constraints of the aggregate itype
620 -- Start of processing for Array_Aggr_Subtype
623 -- Make sure that the list of index constraints is properly attached
624 -- to the tree, and then collect the aggregate bounds.
626 Set_Parent
(Index_Constraints
, N
);
627 Collect_Aggr_Bounds
(N
, 1);
629 -- Build the list of constrained indices of our aggregate itype
631 for J
in 1 .. Aggr_Dimension
loop
632 Create_Index
: declare
633 Index_Base
: constant Entity_Id
:=
634 Base_Type
(Etype
(Aggr_Range
(J
)));
635 Index_Typ
: Entity_Id
;
638 -- Construct the Index subtype, and associate it with the range
639 -- construct that generates it.
642 Create_Itype
(Subtype_Kind
(Ekind
(Index_Base
)), Aggr_Range
(J
));
644 Set_Etype
(Index_Typ
, Index_Base
);
646 if Is_Character_Type
(Index_Base
) then
647 Set_Is_Character_Type
(Index_Typ
);
650 Set_Size_Info
(Index_Typ
, (Index_Base
));
651 Set_RM_Size
(Index_Typ
, RM_Size
(Index_Base
));
652 Set_First_Rep_Item
(Index_Typ
, First_Rep_Item
(Index_Base
));
653 Set_Scalar_Range
(Index_Typ
, Aggr_Range
(J
));
655 if Is_Discrete_Or_Fixed_Point_Type
(Index_Typ
) then
656 Set_RM_Size
(Index_Typ
, UI_From_Int
(Minimum_Size
(Index_Typ
)));
659 Set_Etype
(Aggr_Range
(J
), Index_Typ
);
661 Append
(Aggr_Range
(J
), To
=> Index_Constraints
);
665 -- Now build the Itype
667 Itype
:= Create_Itype
(E_Array_Subtype
, N
);
669 Set_First_Rep_Item
(Itype
, First_Rep_Item
(Typ
));
670 Set_Convention
(Itype
, Convention
(Typ
));
671 Set_Depends_On_Private
(Itype
, Has_Private_Component
(Typ
));
672 Set_Etype
(Itype
, Base_Type
(Typ
));
673 Set_Has_Alignment_Clause
(Itype
, Has_Alignment_Clause
(Typ
));
674 Set_Is_Aliased
(Itype
, Is_Aliased
(Typ
));
675 Set_Depends_On_Private
(Itype
, Depends_On_Private
(Typ
));
677 Copy_Suppress_Status
(Index_Check
, Typ
, Itype
);
678 Copy_Suppress_Status
(Length_Check
, Typ
, Itype
);
680 Set_First_Index
(Itype
, First
(Index_Constraints
));
681 Set_Is_Constrained
(Itype
, True);
682 Set_Is_Internal
(Itype
, True);
683 Init_Size_Align
(Itype
);
685 -- A simple optimization: purely positional aggregates of static
686 -- components should be passed to gigi unexpanded whenever possible,
687 -- and regardless of the staticness of the bounds themselves. Subse-
688 -- quent checks in exp_aggr verify that type is not packed, etc.
690 Set_Size_Known_At_Compile_Time
(Itype
,
692 and then Comes_From_Source
(N
)
693 and then Size_Known_At_Compile_Time
(Component_Type
(Typ
)));
695 -- We always need a freeze node for a packed array subtype, so that
696 -- we can build the Packed_Array_Type corresponding to the subtype.
697 -- If expansion is disabled, the packed array subtype is not built,
698 -- and we must not generate a freeze node for the type, or else it
699 -- will appear incomplete to gigi.
701 if Is_Packed
(Itype
) and then not In_Default_Expression
702 and then Expander_Active
704 Freeze_Itype
(Itype
, N
);
708 end Array_Aggr_Subtype
;
710 --------------------------------
711 -- Check_Misspelled_Component --
712 --------------------------------
714 procedure Check_Misspelled_Component
715 (Elements
: Elist_Id
;
718 Max_Suggestions
: constant := 2;
720 Nr_Of_Suggestions
: Natural := 0;
721 Suggestion_1
: Entity_Id
:= Empty
;
722 Suggestion_2
: Entity_Id
:= Empty
;
723 Component_Elmt
: Elmt_Id
;
726 -- All the components of List are matched against Component and
727 -- a count is maintained of possible misspellings. When at the
728 -- end of the analysis there are one or two (not more!) possible
729 -- misspellings, these misspellings will be suggested as
730 -- possible correction.
732 Component_Elmt
:= First_Elmt
(Elements
);
733 while Nr_Of_Suggestions
<= Max_Suggestions
734 and then Present
(Component_Elmt
)
736 if Is_Bad_Spelling_Of
737 (Chars
(Node
(Component_Elmt
)),
740 Nr_Of_Suggestions
:= Nr_Of_Suggestions
+ 1;
742 case Nr_Of_Suggestions
is
743 when 1 => Suggestion_1
:= Node
(Component_Elmt
);
744 when 2 => Suggestion_2
:= Node
(Component_Elmt
);
749 Next_Elmt
(Component_Elmt
);
752 -- Report at most two suggestions
754 if Nr_Of_Suggestions
= 1 then
756 ("\possible misspelling of&", Component
, Suggestion_1
);
758 elsif Nr_Of_Suggestions
= 2 then
759 Error_Msg_Node_2
:= Suggestion_2
;
761 ("\possible misspelling of& or&", Component
, Suggestion_1
);
763 end Check_Misspelled_Component
;
765 ----------------------------------------
766 -- Check_Static_Discriminated_Subtype --
767 ----------------------------------------
769 procedure Check_Static_Discriminated_Subtype
(T
: Entity_Id
; V
: Node_Id
) is
770 Disc
: constant Entity_Id
:= First_Discriminant
(T
);
775 if Has_Record_Rep_Clause
(T
) then
778 elsif Present
(Next_Discriminant
(Disc
)) then
781 elsif Nkind
(V
) /= N_Integer_Literal
then
785 Comp
:= First_Component
(T
);
786 while Present
(Comp
) loop
787 if Is_Scalar_Type
(Etype
(Comp
)) then
790 elsif Is_Private_Type
(Etype
(Comp
))
791 and then Present
(Full_View
(Etype
(Comp
)))
792 and then Is_Scalar_Type
(Full_View
(Etype
(Comp
)))
796 elsif Is_Array_Type
(Etype
(Comp
)) then
797 if Is_Bit_Packed_Array
(Etype
(Comp
)) then
801 Ind
:= First_Index
(Etype
(Comp
));
802 while Present
(Ind
) loop
803 if Nkind
(Ind
) /= N_Range
804 or else Nkind
(Low_Bound
(Ind
)) /= N_Integer_Literal
805 or else Nkind
(High_Bound
(Ind
)) /= N_Integer_Literal
817 Next_Component
(Comp
);
820 -- On exit, all components have statically known sizes
822 Set_Size_Known_At_Compile_Time
(T
);
823 end Check_Static_Discriminated_Subtype
;
825 --------------------------------
826 -- Make_String_Into_Aggregate --
827 --------------------------------
829 procedure Make_String_Into_Aggregate
(N
: Node_Id
) is
830 Exprs
: constant List_Id
:= New_List
;
831 Loc
: constant Source_Ptr
:= Sloc
(N
);
832 Str
: constant String_Id
:= Strval
(N
);
833 Strlen
: constant Nat
:= String_Length
(Str
);
841 for J
in 1 .. Strlen
loop
842 C
:= Get_String_Char
(Str
, J
);
843 Set_Character_Literal_Name
(C
);
846 Make_Character_Literal
(P
,
848 Char_Literal_Value
=> UI_From_CC
(C
));
849 Set_Etype
(C_Node
, Any_Character
);
850 Append_To
(Exprs
, C_Node
);
853 -- something special for wide strings ???
856 New_N
:= Make_Aggregate
(Loc
, Expressions
=> Exprs
);
857 Set_Analyzed
(New_N
);
858 Set_Etype
(New_N
, Any_Composite
);
861 end Make_String_Into_Aggregate
;
863 -----------------------
864 -- Resolve_Aggregate --
865 -----------------------
867 procedure Resolve_Aggregate
(N
: Node_Id
; Typ
: Entity_Id
) is
868 Pkind
: constant Node_Kind
:= Nkind
(Parent
(N
));
870 Aggr_Subtyp
: Entity_Id
;
871 -- The actual aggregate subtype. This is not necessarily the same as Typ
872 -- which is the subtype of the context in which the aggregate was found.
875 -- Check for aggregates not allowed in configurable run-time mode.
876 -- We allow all cases of aggregates that do not come from source,
877 -- since these are all assumed to be small (e.g. bounds of a string
878 -- literal). We also allow aggregates of types we know to be small.
880 if not Support_Aggregates_On_Target
881 and then Comes_From_Source
(N
)
882 and then (not Known_Static_Esize
(Typ
) or else Esize
(Typ
) > 64)
884 Error_Msg_CRT
("aggregate", N
);
887 -- Ada 2005 (AI-287): Limited aggregates allowed
889 if Is_Limited_Type
(Typ
) and then Ada_Version
< Ada_05
then
890 Error_Msg_N
("aggregate type cannot be limited", N
);
891 Explain_Limited_Type
(Typ
, N
);
893 elsif Is_Class_Wide_Type
(Typ
) then
894 Error_Msg_N
("type of aggregate cannot be class-wide", N
);
896 elsif Typ
= Any_String
897 or else Typ
= Any_Composite
899 Error_Msg_N
("no unique type for aggregate", N
);
900 Set_Etype
(N
, Any_Composite
);
902 elsif Is_Array_Type
(Typ
) and then Null_Record_Present
(N
) then
903 Error_Msg_N
("null record forbidden in array aggregate", N
);
905 elsif Is_Record_Type
(Typ
) then
906 Resolve_Record_Aggregate
(N
, Typ
);
908 elsif Is_Array_Type
(Typ
) then
910 -- First a special test, for the case of a positional aggregate
911 -- of characters which can be replaced by a string literal.
912 -- Do not perform this transformation if this was a string literal
913 -- to start with, whose components needed constraint checks, or if
914 -- the component type is non-static, because it will require those
915 -- checks and be transformed back into an aggregate.
917 if Number_Dimensions
(Typ
) = 1
919 (Root_Type
(Component_Type
(Typ
)) = Standard_Character
921 Root_Type
(Component_Type
(Typ
)) = Standard_Wide_Character
923 Root_Type
(Component_Type
(Typ
)) = Standard_Wide_Wide_Character
)
924 and then No
(Component_Associations
(N
))
925 and then not Is_Limited_Composite
(Typ
)
926 and then not Is_Private_Composite
(Typ
)
927 and then not Is_Bit_Packed_Array
(Typ
)
928 and then Nkind
(Original_Node
(Parent
(N
))) /= N_String_Literal
929 and then Is_Static_Subtype
(Component_Type
(Typ
))
935 Expr
:= First
(Expressions
(N
));
936 while Present
(Expr
) loop
937 exit when Nkind
(Expr
) /= N_Character_Literal
;
944 Expr
:= First
(Expressions
(N
));
945 while Present
(Expr
) loop
946 Store_String_Char
(UI_To_CC
(Char_Literal_Value
(Expr
)));
951 Make_String_Literal
(Sloc
(N
), End_String
));
953 Analyze_And_Resolve
(N
, Typ
);
959 -- Here if we have a real aggregate to deal with
961 Array_Aggregate
: declare
962 Aggr_Resolved
: Boolean;
964 Aggr_Typ
: constant Entity_Id
:= Etype
(Typ
);
965 -- This is the unconstrained array type, which is the type
966 -- against which the aggregate is to be resolved. Typ itself
967 -- is the array type of the context which may not be the same
968 -- subtype as the subtype for the final aggregate.
971 -- In the following we determine whether an others choice is
972 -- allowed inside the array aggregate. The test checks the context
973 -- in which the array aggregate occurs. If the context does not
974 -- permit it, or the aggregate type is unconstrained, an others
975 -- choice is not allowed.
977 -- If expansion is disabled (generic context, or semantics-only
978 -- mode) actual subtypes cannot be constructed, and the type of
979 -- an object may be its unconstrained nominal type. However, if
980 -- the context is an assignment, we assume that "others" is
981 -- allowed, because the target of the assignment will have a
982 -- constrained subtype when fully compiled.
984 -- Note that there is no node for Explicit_Actual_Parameter.
985 -- To test for this context we therefore have to test for node
986 -- N_Parameter_Association which itself appears only if there is a
987 -- formal parameter. Consequently we also need to test for
988 -- N_Procedure_Call_Statement or N_Function_Call.
990 Set_Etype
(N
, Aggr_Typ
); -- may be overridden later on
992 if Is_Constrained
(Typ
) and then
993 (Pkind
= N_Assignment_Statement
or else
994 Pkind
= N_Parameter_Association
or else
995 Pkind
= N_Function_Call
or else
996 Pkind
= N_Procedure_Call_Statement
or else
997 Pkind
= N_Generic_Association
or else
998 Pkind
= N_Formal_Object_Declaration
or else
999 Pkind
= N_Simple_Return_Statement
or else
1000 Pkind
= N_Object_Declaration
or else
1001 Pkind
= N_Component_Declaration
or else
1002 Pkind
= N_Parameter_Specification
or else
1003 Pkind
= N_Qualified_Expression
or else
1004 Pkind
= N_Aggregate
or else
1005 Pkind
= N_Extension_Aggregate
or else
1006 Pkind
= N_Component_Association
)
1009 Resolve_Array_Aggregate
1011 Index
=> First_Index
(Aggr_Typ
),
1012 Index_Constr
=> First_Index
(Typ
),
1013 Component_Typ
=> Component_Type
(Typ
),
1014 Others_Allowed
=> True);
1016 elsif not Expander_Active
1017 and then Pkind
= N_Assignment_Statement
1020 Resolve_Array_Aggregate
1022 Index
=> First_Index
(Aggr_Typ
),
1023 Index_Constr
=> First_Index
(Typ
),
1024 Component_Typ
=> Component_Type
(Typ
),
1025 Others_Allowed
=> True);
1028 Resolve_Array_Aggregate
1030 Index
=> First_Index
(Aggr_Typ
),
1031 Index_Constr
=> First_Index
(Aggr_Typ
),
1032 Component_Typ
=> Component_Type
(Typ
),
1033 Others_Allowed
=> False);
1036 if not Aggr_Resolved
then
1037 Aggr_Subtyp
:= Any_Composite
;
1039 Aggr_Subtyp
:= Array_Aggr_Subtype
(N
, Typ
);
1042 Set_Etype
(N
, Aggr_Subtyp
);
1043 end Array_Aggregate
;
1045 elsif Is_Private_Type
(Typ
)
1046 and then Present
(Full_View
(Typ
))
1047 and then In_Inlined_Body
1048 and then Is_Composite_Type
(Full_View
(Typ
))
1050 Resolve
(N
, Full_View
(Typ
));
1053 Error_Msg_N
("illegal context for aggregate", N
);
1056 -- If we can determine statically that the evaluation of the
1057 -- aggregate raises Constraint_Error, then replace the
1058 -- aggregate with an N_Raise_Constraint_Error node, but set the
1059 -- Etype to the right aggregate subtype. Gigi needs this.
1061 if Raises_Constraint_Error
(N
) then
1062 Aggr_Subtyp
:= Etype
(N
);
1064 Make_Raise_Constraint_Error
(Sloc
(N
),
1065 Reason
=> CE_Range_Check_Failed
));
1066 Set_Raises_Constraint_Error
(N
);
1067 Set_Etype
(N
, Aggr_Subtyp
);
1070 end Resolve_Aggregate
;
1072 -----------------------------
1073 -- Resolve_Array_Aggregate --
1074 -----------------------------
1076 function Resolve_Array_Aggregate
1079 Index_Constr
: Node_Id
;
1080 Component_Typ
: Entity_Id
;
1081 Others_Allowed
: Boolean)
1084 Loc
: constant Source_Ptr
:= Sloc
(N
);
1086 Failure
: constant Boolean := False;
1087 Success
: constant Boolean := True;
1089 Index_Typ
: constant Entity_Id
:= Etype
(Index
);
1090 Index_Typ_Low
: constant Node_Id
:= Type_Low_Bound
(Index_Typ
);
1091 Index_Typ_High
: constant Node_Id
:= Type_High_Bound
(Index_Typ
);
1092 -- The type of the index corresponding to the array sub-aggregate
1093 -- along with its low and upper bounds
1095 Index_Base
: constant Entity_Id
:= Base_Type
(Index_Typ
);
1096 Index_Base_Low
: constant Node_Id
:= Type_Low_Bound
(Index_Base
);
1097 Index_Base_High
: constant Node_Id
:= Type_High_Bound
(Index_Base
);
1098 -- ditto for the base type
1100 function Add
(Val
: Uint
; To
: Node_Id
) return Node_Id
;
1101 -- Creates a new expression node where Val is added to expression To.
1102 -- Tries to constant fold whenever possible. To must be an already
1103 -- analyzed expression.
1105 procedure Check_Bound
(BH
: Node_Id
; AH
: in out Node_Id
);
1106 -- Checks that AH (the upper bound of an array aggregate) is <= BH
1107 -- (the upper bound of the index base type). If the check fails a
1108 -- warning is emitted, the Raises_Constraint_Error Flag of N is set,
1109 -- and AH is replaced with a duplicate of BH.
1111 procedure Check_Bounds
(L
, H
: Node_Id
; AL
, AH
: Node_Id
);
1112 -- Checks that range AL .. AH is compatible with range L .. H. Emits a
1113 -- warning if not and sets the Raises_Constraint_Error Flag in N.
1115 procedure Check_Length
(L
, H
: Node_Id
; Len
: Uint
);
1116 -- Checks that range L .. H contains at least Len elements. Emits a
1117 -- warning if not and sets the Raises_Constraint_Error Flag in N.
1119 function Dynamic_Or_Null_Range
(L
, H
: Node_Id
) return Boolean;
1120 -- Returns True if range L .. H is dynamic or null
1122 procedure Get
(Value
: out Uint
; From
: Node_Id
; OK
: out Boolean);
1123 -- Given expression node From, this routine sets OK to False if it
1124 -- cannot statically evaluate From. Otherwise it stores this static
1125 -- value into Value.
1127 function Resolve_Aggr_Expr
1129 Single_Elmt
: Boolean)
1131 -- Resolves aggregate expression Expr. Returs False if resolution
1132 -- fails. If Single_Elmt is set to False, the expression Expr may be
1133 -- used to initialize several array aggregate elements (this can
1134 -- happen for discrete choices such as "L .. H => Expr" or the others
1135 -- choice). In this event we do not resolve Expr unless expansion is
1136 -- disabled. To know why, see the DELAYED COMPONENT RESOLUTION
1143 function Add
(Val
: Uint
; To
: Node_Id
) return Node_Id
is
1149 if Raises_Constraint_Error
(To
) then
1153 -- First test if we can do constant folding
1155 if Compile_Time_Known_Value
(To
)
1156 or else Nkind
(To
) = N_Integer_Literal
1158 Expr_Pos
:= Make_Integer_Literal
(Loc
, Expr_Value
(To
) + Val
);
1159 Set_Is_Static_Expression
(Expr_Pos
);
1160 Set_Etype
(Expr_Pos
, Etype
(To
));
1161 Set_Analyzed
(Expr_Pos
, Analyzed
(To
));
1163 if not Is_Enumeration_Type
(Index_Typ
) then
1166 -- If we are dealing with enumeration return
1167 -- Index_Typ'Val (Expr_Pos)
1171 Make_Attribute_Reference
1173 Prefix
=> New_Reference_To
(Index_Typ
, Loc
),
1174 Attribute_Name
=> Name_Val
,
1175 Expressions
=> New_List
(Expr_Pos
));
1181 -- If we are here no constant folding possible
1183 if not Is_Enumeration_Type
(Index_Base
) then
1186 Left_Opnd
=> Duplicate_Subexpr
(To
),
1187 Right_Opnd
=> Make_Integer_Literal
(Loc
, Val
));
1189 -- If we are dealing with enumeration return
1190 -- Index_Typ'Val (Index_Typ'Pos (To) + Val)
1194 Make_Attribute_Reference
1196 Prefix
=> New_Reference_To
(Index_Typ
, Loc
),
1197 Attribute_Name
=> Name_Pos
,
1198 Expressions
=> New_List
(Duplicate_Subexpr
(To
)));
1202 Left_Opnd
=> To_Pos
,
1203 Right_Opnd
=> Make_Integer_Literal
(Loc
, Val
));
1206 Make_Attribute_Reference
1208 Prefix
=> New_Reference_To
(Index_Typ
, Loc
),
1209 Attribute_Name
=> Name_Val
,
1210 Expressions
=> New_List
(Expr_Pos
));
1220 procedure Check_Bound
(BH
: Node_Id
; AH
: in out Node_Id
) is
1228 Get
(Value
=> Val_BH
, From
=> BH
, OK
=> OK_BH
);
1229 Get
(Value
=> Val_AH
, From
=> AH
, OK
=> OK_AH
);
1231 if OK_BH
and then OK_AH
and then Val_BH
< Val_AH
then
1232 Set_Raises_Constraint_Error
(N
);
1233 Error_Msg_N
("upper bound out of range?", AH
);
1234 Error_Msg_N
("\Constraint_Error will be raised at run-time?", AH
);
1236 -- You need to set AH to BH or else in the case of enumerations
1237 -- indices we will not be able to resolve the aggregate bounds.
1239 AH
:= Duplicate_Subexpr
(BH
);
1247 procedure Check_Bounds
(L
, H
: Node_Id
; AL
, AH
: Node_Id
) is
1258 pragma Warnings
(Off
, OK_AL
);
1259 pragma Warnings
(Off
, OK_AH
);
1262 if Raises_Constraint_Error
(N
)
1263 or else Dynamic_Or_Null_Range
(AL
, AH
)
1268 Get
(Value
=> Val_L
, From
=> L
, OK
=> OK_L
);
1269 Get
(Value
=> Val_H
, From
=> H
, OK
=> OK_H
);
1271 Get
(Value
=> Val_AL
, From
=> AL
, OK
=> OK_AL
);
1272 Get
(Value
=> Val_AH
, From
=> AH
, OK
=> OK_AH
);
1274 if OK_L
and then Val_L
> Val_AL
then
1275 Set_Raises_Constraint_Error
(N
);
1276 Error_Msg_N
("lower bound of aggregate out of range?", N
);
1277 Error_Msg_N
("\Constraint_Error will be raised at run-time?", N
);
1280 if OK_H
and then Val_H
< Val_AH
then
1281 Set_Raises_Constraint_Error
(N
);
1282 Error_Msg_N
("upper bound of aggregate out of range?", N
);
1283 Error_Msg_N
("\Constraint_Error will be raised at run-time?", N
);
1291 procedure Check_Length
(L
, H
: Node_Id
; Len
: Uint
) is
1301 if Raises_Constraint_Error
(N
) then
1305 Get
(Value
=> Val_L
, From
=> L
, OK
=> OK_L
);
1306 Get
(Value
=> Val_H
, From
=> H
, OK
=> OK_H
);
1308 if not OK_L
or else not OK_H
then
1312 -- If null range length is zero
1314 if Val_L
> Val_H
then
1315 Range_Len
:= Uint_0
;
1317 Range_Len
:= Val_H
- Val_L
+ 1;
1320 if Range_Len
< Len
then
1321 Set_Raises_Constraint_Error
(N
);
1322 Error_Msg_N
("too many elements?", N
);
1323 Error_Msg_N
("\Constraint_Error will be raised at run-time?", N
);
1327 ---------------------------
1328 -- Dynamic_Or_Null_Range --
1329 ---------------------------
1331 function Dynamic_Or_Null_Range
(L
, H
: Node_Id
) return Boolean is
1339 Get
(Value
=> Val_L
, From
=> L
, OK
=> OK_L
);
1340 Get
(Value
=> Val_H
, From
=> H
, OK
=> OK_H
);
1342 return not OK_L
or else not OK_H
1343 or else not Is_OK_Static_Expression
(L
)
1344 or else not Is_OK_Static_Expression
(H
)
1345 or else Val_L
> Val_H
;
1346 end Dynamic_Or_Null_Range
;
1352 procedure Get
(Value
: out Uint
; From
: Node_Id
; OK
: out Boolean) is
1356 if Compile_Time_Known_Value
(From
) then
1357 Value
:= Expr_Value
(From
);
1359 -- If expression From is something like Some_Type'Val (10) then
1362 elsif Nkind
(From
) = N_Attribute_Reference
1363 and then Attribute_Name
(From
) = Name_Val
1364 and then Compile_Time_Known_Value
(First
(Expressions
(From
)))
1366 Value
:= Expr_Value
(First
(Expressions
(From
)));
1374 -----------------------
1375 -- Resolve_Aggr_Expr --
1376 -----------------------
1378 function Resolve_Aggr_Expr
1380 Single_Elmt
: Boolean)
1383 Nxt_Ind
: constant Node_Id
:= Next_Index
(Index
);
1384 Nxt_Ind_Constr
: constant Node_Id
:= Next_Index
(Index_Constr
);
1385 -- Index is the current index corresponding to the expresion
1387 Resolution_OK
: Boolean := True;
1388 -- Set to False if resolution of the expression failed
1391 -- If the array type against which we are resolving the aggregate
1392 -- has several dimensions, the expressions nested inside the
1393 -- aggregate must be further aggregates (or strings).
1395 if Present
(Nxt_Ind
) then
1396 if Nkind
(Expr
) /= N_Aggregate
then
1398 -- A string literal can appear where a one-dimensional array
1399 -- of characters is expected. If the literal looks like an
1400 -- operator, it is still an operator symbol, which will be
1401 -- transformed into a string when analyzed.
1403 if Is_Character_Type
(Component_Typ
)
1404 and then No
(Next_Index
(Nxt_Ind
))
1405 and then (Nkind
(Expr
) = N_String_Literal
1406 or else Nkind
(Expr
) = N_Operator_Symbol
)
1408 -- A string literal used in a multidimensional array
1409 -- aggregate in place of the final one-dimensional
1410 -- aggregate must not be enclosed in parentheses.
1412 if Paren_Count
(Expr
) /= 0 then
1413 Error_Msg_N
("no parenthesis allowed here", Expr
);
1416 Make_String_Into_Aggregate
(Expr
);
1419 Error_Msg_N
("nested array aggregate expected", Expr
);
1424 -- Ada 2005 (AI-231): Propagate the type to the nested aggregate.
1425 -- Required to check the null-exclusion attribute (if present).
1426 -- This value may be overridden later on.
1428 Set_Etype
(Expr
, Etype
(N
));
1430 Resolution_OK
:= Resolve_Array_Aggregate
1431 (Expr
, Nxt_Ind
, Nxt_Ind_Constr
, Component_Typ
, Others_Allowed
);
1433 -- Do not resolve the expressions of discrete or others choices
1434 -- unless the expression covers a single component, or the expander
1438 or else not Expander_Active
1439 or else In_Default_Expression
1441 Analyze_And_Resolve
(Expr
, Component_Typ
);
1442 Check_Non_Static_Context
(Expr
);
1443 Aggregate_Constraint_Checks
(Expr
, Component_Typ
);
1444 Check_Unset_Reference
(Expr
);
1447 if Raises_Constraint_Error
(Expr
)
1448 and then Nkind
(Parent
(Expr
)) /= N_Component_Association
1450 Set_Raises_Constraint_Error
(N
);
1453 return Resolution_OK
;
1454 end Resolve_Aggr_Expr
;
1456 -- Variables local to Resolve_Array_Aggregate
1463 pragma Warnings
(Off
, Discard
);
1465 Aggr_Low
: Node_Id
:= Empty
;
1466 Aggr_High
: Node_Id
:= Empty
;
1467 -- The actual low and high bounds of this sub-aggregate
1469 Choices_Low
: Node_Id
:= Empty
;
1470 Choices_High
: Node_Id
:= Empty
;
1471 -- The lowest and highest discrete choices values for a named aggregate
1473 Nb_Elements
: Uint
:= Uint_0
;
1474 -- The number of elements in a positional aggregate
1476 Others_Present
: Boolean := False;
1478 Nb_Choices
: Nat
:= 0;
1479 -- Contains the overall number of named choices in this sub-aggregate
1481 Nb_Discrete_Choices
: Nat
:= 0;
1482 -- The overall number of discrete choices (not counting others choice)
1484 Case_Table_Size
: Nat
;
1485 -- Contains the size of the case table needed to sort aggregate choices
1487 -- Start of processing for Resolve_Array_Aggregate
1490 -- STEP 1: make sure the aggregate is correctly formatted
1492 if Present
(Component_Associations
(N
)) then
1493 Assoc
:= First
(Component_Associations
(N
));
1494 while Present
(Assoc
) loop
1495 Choice
:= First
(Choices
(Assoc
));
1496 while Present
(Choice
) loop
1497 if Nkind
(Choice
) = N_Others_Choice
then
1498 Others_Present
:= True;
1500 if Choice
/= First
(Choices
(Assoc
))
1501 or else Present
(Next
(Choice
))
1504 ("OTHERS must appear alone in a choice list", Choice
);
1508 if Present
(Next
(Assoc
)) then
1510 ("OTHERS must appear last in an aggregate", Choice
);
1514 if Ada_Version
= Ada_83
1515 and then Assoc
/= First
(Component_Associations
(N
))
1516 and then (Nkind
(Parent
(N
)) = N_Assignment_Statement
1518 Nkind
(Parent
(N
)) = N_Object_Declaration
)
1521 ("(Ada 83) illegal context for OTHERS choice", N
);
1525 Nb_Choices
:= Nb_Choices
+ 1;
1533 -- At this point we know that the others choice, if present, is by
1534 -- itself and appears last in the aggregate. Check if we have mixed
1535 -- positional and discrete associations (other than the others choice).
1537 if Present
(Expressions
(N
))
1538 and then (Nb_Choices
> 1
1539 or else (Nb_Choices
= 1 and then not Others_Present
))
1542 ("named association cannot follow positional association",
1543 First
(Choices
(First
(Component_Associations
(N
)))));
1547 -- Test for the validity of an others choice if present
1549 if Others_Present
and then not Others_Allowed
then
1551 ("OTHERS choice not allowed here",
1552 First
(Choices
(First
(Component_Associations
(N
)))));
1556 -- Protect against cascaded errors
1558 if Etype
(Index_Typ
) = Any_Type
then
1562 -- STEP 2: Process named components
1564 if No
(Expressions
(N
)) then
1566 if Others_Present
then
1567 Case_Table_Size
:= Nb_Choices
- 1;
1569 Case_Table_Size
:= Nb_Choices
;
1575 -- Denote the lowest and highest values in an aggregate choice
1579 -- High end of one range and Low end of the next. Should be
1580 -- contiguous if there is no hole in the list of values.
1582 Missing_Values
: Boolean;
1583 -- Set True if missing index values
1585 S_Low
: Node_Id
:= Empty
;
1586 S_High
: Node_Id
:= Empty
;
1587 -- if a choice in an aggregate is a subtype indication these
1588 -- denote the lowest and highest values of the subtype
1590 Table
: Case_Table_Type
(1 .. Case_Table_Size
);
1591 -- Used to sort all the different choice values
1593 Single_Choice
: Boolean;
1594 -- Set to true every time there is a single discrete choice in a
1595 -- discrete association
1597 Prev_Nb_Discrete_Choices
: Nat
;
1598 -- Used to keep track of the number of discrete choices
1599 -- in the current association.
1602 -- STEP 2 (A): Check discrete choices validity
1604 Assoc
:= First
(Component_Associations
(N
));
1605 while Present
(Assoc
) loop
1606 Prev_Nb_Discrete_Choices
:= Nb_Discrete_Choices
;
1607 Choice
:= First
(Choices
(Assoc
));
1611 if Nkind
(Choice
) = N_Others_Choice
then
1612 Single_Choice
:= False;
1615 -- Test for subtype mark without constraint
1617 elsif Is_Entity_Name
(Choice
) and then
1618 Is_Type
(Entity
(Choice
))
1620 if Base_Type
(Entity
(Choice
)) /= Index_Base
then
1622 ("invalid subtype mark in aggregate choice",
1627 elsif Nkind
(Choice
) = N_Subtype_Indication
then
1628 Resolve_Discrete_Subtype_Indication
(Choice
, Index_Base
);
1630 -- Does the subtype indication evaluation raise CE ?
1632 Get_Index_Bounds
(Subtype_Mark
(Choice
), S_Low
, S_High
);
1633 Get_Index_Bounds
(Choice
, Low
, High
);
1634 Check_Bounds
(S_Low
, S_High
, Low
, High
);
1636 else -- Choice is a range or an expression
1637 Resolve
(Choice
, Index_Base
);
1638 Check_Unset_Reference
(Choice
);
1639 Check_Non_Static_Context
(Choice
);
1641 -- Do not range check a choice. This check is redundant
1642 -- since this test is already performed when we check
1643 -- that the bounds of the array aggregate are within
1646 Set_Do_Range_Check
(Choice
, False);
1649 -- If we could not resolve the discrete choice stop here
1651 if Etype
(Choice
) = Any_Type
then
1654 -- If the discrete choice raises CE get its original bounds
1656 elsif Nkind
(Choice
) = N_Raise_Constraint_Error
then
1657 Set_Raises_Constraint_Error
(N
);
1658 Get_Index_Bounds
(Original_Node
(Choice
), Low
, High
);
1660 -- Otherwise get its bounds as usual
1663 Get_Index_Bounds
(Choice
, Low
, High
);
1666 if (Dynamic_Or_Null_Range
(Low
, High
)
1667 or else (Nkind
(Choice
) = N_Subtype_Indication
1669 Dynamic_Or_Null_Range
(S_Low
, S_High
)))
1670 and then Nb_Choices
/= 1
1673 ("dynamic or empty choice in aggregate " &
1674 "must be the only choice", Choice
);
1678 Nb_Discrete_Choices
:= Nb_Discrete_Choices
+ 1;
1679 Table
(Nb_Discrete_Choices
).Choice_Lo
:= Low
;
1680 Table
(Nb_Discrete_Choices
).Choice_Hi
:= High
;
1686 -- Check if we have a single discrete choice and whether
1687 -- this discrete choice specifies a single value.
1690 (Nb_Discrete_Choices
= Prev_Nb_Discrete_Choices
+ 1)
1691 and then (Low
= High
);
1697 -- Ada 2005 (AI-231)
1699 if Ada_Version
>= Ada_05
1700 and then Known_Null
(Expression
(Assoc
))
1702 Check_Can_Never_Be_Null
(Etype
(N
), Expression
(Assoc
));
1705 -- Ada 2005 (AI-287): In case of default initialized component
1706 -- we delay the resolution to the expansion phase
1708 if Box_Present
(Assoc
) then
1710 -- Ada 2005 (AI-287): In case of default initialization
1711 -- of a component the expander will generate calls to
1712 -- the corresponding initialization subprogram.
1716 elsif not Resolve_Aggr_Expr
(Expression
(Assoc
),
1717 Single_Elmt
=> Single_Choice
)
1725 -- If aggregate contains more than one choice then these must be
1726 -- static. Sort them and check that they are contiguous
1728 if Nb_Discrete_Choices
> 1 then
1729 Sort_Case_Table
(Table
);
1730 Missing_Values
:= False;
1732 Outer
: for J
in 1 .. Nb_Discrete_Choices
- 1 loop
1733 if Expr_Value
(Table
(J
).Choice_Hi
) >=
1734 Expr_Value
(Table
(J
+ 1).Choice_Lo
)
1737 ("duplicate choice values in array aggregate",
1738 Table
(J
).Choice_Hi
);
1741 elsif not Others_Present
then
1743 Hi_Val
:= Expr_Value
(Table
(J
).Choice_Hi
);
1744 Lo_Val
:= Expr_Value
(Table
(J
+ 1).Choice_Lo
);
1746 -- If missing values, output error messages
1748 if Lo_Val
- Hi_Val
> 1 then
1750 -- Header message if not first missing value
1752 if not Missing_Values
then
1754 ("missing index value(s) in array aggregate", N
);
1755 Missing_Values
:= True;
1758 -- Output values of missing indexes
1760 Lo_Val
:= Lo_Val
- 1;
1761 Hi_Val
:= Hi_Val
+ 1;
1763 -- Enumeration type case
1765 if Is_Enumeration_Type
(Index_Typ
) then
1768 (Get_Enum_Lit_From_Pos
1769 (Index_Typ
, Hi_Val
, Loc
));
1771 if Lo_Val
= Hi_Val
then
1772 Error_Msg_N
("\ %", N
);
1776 (Get_Enum_Lit_From_Pos
1777 (Index_Typ
, Lo_Val
, Loc
));
1778 Error_Msg_N
("\ % .. %", N
);
1781 -- Integer types case
1784 Error_Msg_Uint_1
:= Hi_Val
;
1786 if Lo_Val
= Hi_Val
then
1787 Error_Msg_N
("\ ^", N
);
1789 Error_Msg_Uint_2
:= Lo_Val
;
1790 Error_Msg_N
("\ ^ .. ^", N
);
1797 if Missing_Values
then
1798 Set_Etype
(N
, Any_Composite
);
1803 -- STEP 2 (B): Compute aggregate bounds and min/max choices values
1805 if Nb_Discrete_Choices
> 0 then
1806 Choices_Low
:= Table
(1).Choice_Lo
;
1807 Choices_High
:= Table
(Nb_Discrete_Choices
).Choice_Hi
;
1810 if Others_Present
then
1811 Get_Index_Bounds
(Index_Constr
, Aggr_Low
, Aggr_High
);
1814 Aggr_Low
:= Choices_Low
;
1815 Aggr_High
:= Choices_High
;
1819 -- STEP 3: Process positional components
1822 -- STEP 3 (A): Process positional elements
1824 Expr
:= First
(Expressions
(N
));
1825 Nb_Elements
:= Uint_0
;
1826 while Present
(Expr
) loop
1827 Nb_Elements
:= Nb_Elements
+ 1;
1829 -- Ada 2005 (AI-231)
1831 if Ada_Version
>= Ada_05
1832 and then Known_Null
(Expr
)
1834 Check_Can_Never_Be_Null
(Etype
(N
), Expr
);
1837 if not Resolve_Aggr_Expr
(Expr
, Single_Elmt
=> True) then
1844 if Others_Present
then
1845 Assoc
:= Last
(Component_Associations
(N
));
1847 -- Ada 2005 (AI-231)
1849 if Ada_Version
>= Ada_05
1850 and then Known_Null
(Assoc
)
1852 Check_Can_Never_Be_Null
(Etype
(N
), Expression
(Assoc
));
1855 -- Ada 2005 (AI-287): In case of default initialized component
1856 -- we delay the resolution to the expansion phase.
1858 if Box_Present
(Assoc
) then
1860 -- Ada 2005 (AI-287): In case of default initialization
1861 -- of a component the expander will generate calls to
1862 -- the corresponding initialization subprogram.
1866 elsif not Resolve_Aggr_Expr
(Expression
(Assoc
),
1867 Single_Elmt
=> False)
1873 -- STEP 3 (B): Compute the aggregate bounds
1875 if Others_Present
then
1876 Get_Index_Bounds
(Index_Constr
, Aggr_Low
, Aggr_High
);
1879 if Others_Allowed
then
1880 Get_Index_Bounds
(Index_Constr
, Aggr_Low
, Discard
);
1882 Aggr_Low
:= Index_Typ_Low
;
1885 Aggr_High
:= Add
(Nb_Elements
- 1, To
=> Aggr_Low
);
1886 Check_Bound
(Index_Base_High
, Aggr_High
);
1890 -- STEP 4: Perform static aggregate checks and save the bounds
1894 Check_Bounds
(Index_Typ_Low
, Index_Typ_High
, Aggr_Low
, Aggr_High
);
1895 Check_Bounds
(Index_Base_Low
, Index_Base_High
, Aggr_Low
, Aggr_High
);
1899 if Others_Present
and then Nb_Discrete_Choices
> 0 then
1900 Check_Bounds
(Aggr_Low
, Aggr_High
, Choices_Low
, Choices_High
);
1901 Check_Bounds
(Index_Typ_Low
, Index_Typ_High
,
1902 Choices_Low
, Choices_High
);
1903 Check_Bounds
(Index_Base_Low
, Index_Base_High
,
1904 Choices_Low
, Choices_High
);
1908 elsif Others_Present
and then Nb_Elements
> 0 then
1909 Check_Length
(Aggr_Low
, Aggr_High
, Nb_Elements
);
1910 Check_Length
(Index_Typ_Low
, Index_Typ_High
, Nb_Elements
);
1911 Check_Length
(Index_Base_Low
, Index_Base_High
, Nb_Elements
);
1914 if Raises_Constraint_Error
(Aggr_Low
)
1915 or else Raises_Constraint_Error
(Aggr_High
)
1917 Set_Raises_Constraint_Error
(N
);
1920 Aggr_Low
:= Duplicate_Subexpr
(Aggr_Low
);
1922 -- Do not duplicate Aggr_High if Aggr_High = Aggr_Low + Nb_Elements
1923 -- since the addition node returned by Add is not yet analyzed. Attach
1924 -- to tree and analyze first. Reset analyzed flag to insure it will get
1925 -- analyzed when it is a literal bound whose type must be properly set.
1927 if Others_Present
or else Nb_Discrete_Choices
> 0 then
1928 Aggr_High
:= Duplicate_Subexpr
(Aggr_High
);
1930 if Etype
(Aggr_High
) = Universal_Integer
then
1931 Set_Analyzed
(Aggr_High
, False);
1935 Set_Aggregate_Bounds
1936 (N
, Make_Range
(Loc
, Low_Bound
=> Aggr_Low
, High_Bound
=> Aggr_High
));
1938 -- The bounds may contain expressions that must be inserted upwards.
1939 -- Attach them fully to the tree. After analysis, remove side effects
1940 -- from upper bound, if still needed.
1942 Set_Parent
(Aggregate_Bounds
(N
), N
);
1943 Analyze_And_Resolve
(Aggregate_Bounds
(N
), Index_Typ
);
1944 Check_Unset_Reference
(Aggregate_Bounds
(N
));
1946 if not Others_Present
and then Nb_Discrete_Choices
= 0 then
1947 Set_High_Bound
(Aggregate_Bounds
(N
),
1948 Duplicate_Subexpr
(High_Bound
(Aggregate_Bounds
(N
))));
1952 end Resolve_Array_Aggregate
;
1954 ---------------------------------
1955 -- Resolve_Extension_Aggregate --
1956 ---------------------------------
1958 -- There are two cases to consider:
1960 -- a) If the ancestor part is a type mark, the components needed are
1961 -- the difference between the components of the expected type and the
1962 -- components of the given type mark.
1964 -- b) If the ancestor part is an expression, it must be unambiguous,
1965 -- and once we have its type we can also compute the needed components
1966 -- as in the previous case. In both cases, if the ancestor type is not
1967 -- the immediate ancestor, we have to build this ancestor recursively.
1969 -- In both cases discriminants of the ancestor type do not play a
1970 -- role in the resolution of the needed components, because inherited
1971 -- discriminants cannot be used in a type extension. As a result we can
1972 -- compute independently the list of components of the ancestor type and
1973 -- of the expected type.
1975 procedure Resolve_Extension_Aggregate
(N
: Node_Id
; Typ
: Entity_Id
) is
1976 A
: constant Node_Id
:= Ancestor_Part
(N
);
1981 function Valid_Ancestor_Type
return Boolean;
1982 -- Verify that the type of the ancestor part is a non-private ancestor
1983 -- of the expected type.
1985 -------------------------
1986 -- Valid_Ancestor_Type --
1987 -------------------------
1989 function Valid_Ancestor_Type
return Boolean is
1990 Imm_Type
: Entity_Id
;
1993 Imm_Type
:= Base_Type
(Typ
);
1994 while Is_Derived_Type
(Imm_Type
)
1995 and then Etype
(Imm_Type
) /= Base_Type
(A_Type
)
1997 Imm_Type
:= Etype
(Base_Type
(Imm_Type
));
2000 if Etype
(Imm_Type
) /= Base_Type
(A_Type
) then
2001 Error_Msg_NE
("expect ancestor type of &", A
, Typ
);
2006 end Valid_Ancestor_Type
;
2008 -- Start of processing for Resolve_Extension_Aggregate
2013 if not Is_Tagged_Type
(Typ
) then
2014 Error_Msg_N
("type of extension aggregate must be tagged", N
);
2017 elsif Is_Limited_Type
(Typ
) then
2019 -- Ada 2005 (AI-287): Limited aggregates are allowed
2021 if Ada_Version
< Ada_05
then
2022 Error_Msg_N
("aggregate type cannot be limited", N
);
2023 Explain_Limited_Type
(Typ
, N
);
2027 elsif Is_Class_Wide_Type
(Typ
) then
2028 Error_Msg_N
("aggregate cannot be of a class-wide type", N
);
2032 if Is_Entity_Name
(A
)
2033 and then Is_Type
(Entity
(A
))
2035 A_Type
:= Get_Full_View
(Entity
(A
));
2037 if Valid_Ancestor_Type
then
2038 Set_Entity
(A
, A_Type
);
2039 Set_Etype
(A
, A_Type
);
2041 Validate_Ancestor_Part
(N
);
2042 Resolve_Record_Aggregate
(N
, Typ
);
2045 elsif Nkind
(A
) /= N_Aggregate
then
2046 if Is_Overloaded
(A
) then
2049 Get_First_Interp
(A
, I
, It
);
2050 while Present
(It
.Typ
) loop
2051 if Is_Tagged_Type
(It
.Typ
)
2052 and then not Is_Limited_Type
(It
.Typ
)
2054 if A_Type
/= Any_Type
then
2055 Error_Msg_N
("cannot resolve expression", A
);
2062 Get_Next_Interp
(I
, It
);
2065 if A_Type
= Any_Type
then
2067 ("ancestor part must be non-limited tagged type", A
);
2072 A_Type
:= Etype
(A
);
2075 if Valid_Ancestor_Type
then
2076 Resolve
(A
, A_Type
);
2077 Check_Unset_Reference
(A
);
2078 Check_Non_Static_Context
(A
);
2080 if Is_Class_Wide_Type
(Etype
(A
))
2081 and then Nkind
(Original_Node
(A
)) = N_Function_Call
2083 -- If the ancestor part is a dispatching call, it appears
2084 -- statically to be a legal ancestor, but it yields any
2085 -- member of the class, and it is not possible to determine
2086 -- whether it is an ancestor of the extension aggregate (much
2087 -- less which ancestor). It is not possible to determine the
2088 -- required components of the extension part.
2090 -- This check implements AI-306, which in fact was motivated
2091 -- by an ACT query to the ARG after this test was added.
2093 Error_Msg_N
("ancestor part must be statically tagged", A
);
2095 Resolve_Record_Aggregate
(N
, Typ
);
2100 Error_Msg_N
("no unique type for this aggregate", A
);
2102 end Resolve_Extension_Aggregate
;
2104 ------------------------------
2105 -- Resolve_Record_Aggregate --
2106 ------------------------------
2108 procedure Resolve_Record_Aggregate
(N
: Node_Id
; Typ
: Entity_Id
) is
2110 -- N_Component_Association node belonging to the input aggregate N
2113 Positional_Expr
: Node_Id
;
2114 Component
: Entity_Id
;
2115 Component_Elmt
: Elmt_Id
;
2117 Components
: constant Elist_Id
:= New_Elmt_List
;
2118 -- Components is the list of the record components whose value must
2119 -- be provided in the aggregate. This list does include discriminants.
2121 New_Assoc_List
: constant List_Id
:= New_List
;
2122 New_Assoc
: Node_Id
;
2123 -- New_Assoc_List is the newly built list of N_Component_Association
2124 -- nodes. New_Assoc is one such N_Component_Association node in it.
2125 -- Please note that while Assoc and New_Assoc contain the same
2126 -- kind of nodes, they are used to iterate over two different
2127 -- N_Component_Association lists.
2129 Others_Etype
: Entity_Id
:= Empty
;
2130 -- This variable is used to save the Etype of the last record component
2131 -- that takes its value from the others choice. Its purpose is:
2133 -- (a) make sure the others choice is useful
2135 -- (b) make sure the type of all the components whose value is
2136 -- subsumed by the others choice are the same.
2138 -- This variable is updated as a side effect of function Get_Value
2140 Is_Box_Present
: Boolean := False;
2141 Others_Box
: Boolean := False;
2142 -- Ada 2005 (AI-287): Variables used in case of default initialization
2143 -- to provide a functionality similar to Others_Etype. Box_Present
2144 -- indicates that the component takes its default initialization;
2145 -- Others_Box indicates that at least one component takes its default
2146 -- initialization. Similar to Others_Etype, they are also updated as a
2147 -- side effect of function Get_Value.
2149 procedure Add_Association
2150 (Component
: Entity_Id
;
2152 Is_Box_Present
: Boolean := False);
2153 -- Builds a new N_Component_Association node which associates
2154 -- Component to expression Expr and adds it to the new association
2155 -- list New_Assoc_List being built.
2157 function Discr_Present
(Discr
: Entity_Id
) return Boolean;
2158 -- If aggregate N is a regular aggregate this routine will return True.
2159 -- Otherwise, if N is an extension aggregate, Discr is a discriminant
2160 -- whose value may already have been specified by N's ancestor part,
2161 -- this routine checks whether this is indeed the case and if so
2162 -- returns False, signaling that no value for Discr should appear in the
2163 -- N's aggregate part. Also, in this case, the routine appends to
2164 -- New_Assoc_List Discr the discriminant value specified in the ancestor
2170 Consider_Others_Choice
: Boolean := False)
2172 -- Given a record component stored in parameter Compon, the
2173 -- following function returns its value as it appears in the list
2174 -- From, which is a list of N_Component_Association nodes. If no
2175 -- component association has a choice for the searched component,
2176 -- the value provided by the others choice is returned, if there
2177 -- is one and Consider_Others_Choice is set to true. Otherwise
2178 -- Empty is returned. If there is more than one component association
2179 -- giving a value for the searched record component, an error message
2180 -- is emitted and the first found value is returned.
2182 -- If Consider_Others_Choice is set and the returned expression comes
2183 -- from the others choice, then Others_Etype is set as a side effect.
2184 -- An error message is emitted if the components taking their value
2185 -- from the others choice do not have same type.
2187 procedure Resolve_Aggr_Expr
(Expr
: Node_Id
; Component
: Node_Id
);
2188 -- Analyzes and resolves expression Expr against the Etype of the
2189 -- Component. This routine also applies all appropriate checks to Expr.
2190 -- It finally saves a Expr in the newly created association list that
2191 -- will be attached to the final record aggregate. Note that if the
2192 -- Parent pointer of Expr is not set then Expr was produced with a
2193 -- New_Copy_Tree or some such.
2195 ---------------------
2196 -- Add_Association --
2197 ---------------------
2199 procedure Add_Association
2200 (Component
: Entity_Id
;
2202 Is_Box_Present
: Boolean := False)
2204 Choice_List
: constant List_Id
:= New_List
;
2205 New_Assoc
: Node_Id
;
2208 Append
(New_Occurrence_Of
(Component
, Sloc
(Expr
)), Choice_List
);
2210 Make_Component_Association
(Sloc
(Expr
),
2211 Choices
=> Choice_List
,
2213 Box_Present
=> Is_Box_Present
);
2214 Append
(New_Assoc
, New_Assoc_List
);
2215 end Add_Association
;
2221 function Discr_Present
(Discr
: Entity_Id
) return Boolean is
2222 Regular_Aggr
: constant Boolean := Nkind
(N
) /= N_Extension_Aggregate
;
2227 Discr_Expr
: Node_Id
;
2229 Ancestor_Typ
: Entity_Id
;
2230 Orig_Discr
: Entity_Id
;
2232 D_Val
: Elmt_Id
:= No_Elmt
; -- stop junk warning
2234 Ancestor_Is_Subtyp
: Boolean;
2237 if Regular_Aggr
then
2241 Ancestor
:= Ancestor_Part
(N
);
2242 Ancestor_Typ
:= Etype
(Ancestor
);
2243 Loc
:= Sloc
(Ancestor
);
2245 Ancestor_Is_Subtyp
:=
2246 Is_Entity_Name
(Ancestor
) and then Is_Type
(Entity
(Ancestor
));
2248 -- If the ancestor part has no discriminants clearly N's aggregate
2249 -- part must provide a value for Discr.
2251 if not Has_Discriminants
(Ancestor_Typ
) then
2254 -- If the ancestor part is an unconstrained subtype mark then the
2255 -- Discr must be present in N's aggregate part.
2257 elsif Ancestor_Is_Subtyp
2258 and then not Is_Constrained
(Entity
(Ancestor
))
2263 -- Now look to see if Discr was specified in the ancestor part
2265 if Ancestor_Is_Subtyp
then
2266 D_Val
:= First_Elmt
(Discriminant_Constraint
(Entity
(Ancestor
)));
2269 Orig_Discr
:= Original_Record_Component
(Discr
);
2271 D
:= First_Discriminant
(Ancestor_Typ
);
2272 while Present
(D
) loop
2274 -- If Ancestor has already specified Disc value than insert its
2275 -- value in the final aggregate.
2277 if Original_Record_Component
(D
) = Orig_Discr
then
2278 if Ancestor_Is_Subtyp
then
2279 Discr_Expr
:= New_Copy_Tree
(Node
(D_Val
));
2282 Make_Selected_Component
(Loc
,
2283 Prefix
=> Duplicate_Subexpr
(Ancestor
),
2284 Selector_Name
=> New_Occurrence_Of
(Discr
, Loc
));
2287 Resolve_Aggr_Expr
(Discr_Expr
, Discr
);
2291 Next_Discriminant
(D
);
2293 if Ancestor_Is_Subtyp
then
2308 Consider_Others_Choice
: Boolean := False)
2312 Expr
: Node_Id
:= Empty
;
2313 Selector_Name
: Node_Id
;
2316 Is_Box_Present
:= False;
2318 if Present
(From
) then
2319 Assoc
:= First
(From
);
2324 while Present
(Assoc
) loop
2325 Selector_Name
:= First
(Choices
(Assoc
));
2326 while Present
(Selector_Name
) loop
2327 if Nkind
(Selector_Name
) = N_Others_Choice
then
2328 if Consider_Others_Choice
and then No
(Expr
) then
2330 -- We need to duplicate the expression for each
2331 -- successive component covered by the others choice.
2332 -- This is redundant if the others_choice covers only
2333 -- one component (small optimization possible???), but
2334 -- indispensable otherwise, because each one must be
2335 -- expanded individually to preserve side-effects.
2337 -- Ada 2005 (AI-287): In case of default initialization
2338 -- of components, we duplicate the corresponding default
2339 -- expression (from the record type declaration). The
2340 -- copy must carry the sloc of the association (not the
2341 -- original expression) to prevent spurious elaboration
2342 -- checks when the default includes function calls.
2344 if Box_Present
(Assoc
) then
2346 Is_Box_Present
:= True;
2348 if Expander_Active
then
2351 (Expression
(Parent
(Compon
)),
2352 New_Sloc
=> Sloc
(Assoc
));
2354 return Expression
(Parent
(Compon
));
2358 if Present
(Others_Etype
) and then
2359 Base_Type
(Others_Etype
) /= Base_Type
(Etype
2362 Error_Msg_N
("components in OTHERS choice must " &
2363 "have same type", Selector_Name
);
2366 Others_Etype
:= Etype
(Compon
);
2368 if Expander_Active
then
2369 return New_Copy_Tree
(Expression
(Assoc
));
2371 return Expression
(Assoc
);
2376 elsif Chars
(Compon
) = Chars
(Selector_Name
) then
2379 -- Ada 2005 (AI-231)
2381 if Ada_Version
>= Ada_05
2382 and then Known_Null
(Expression
(Assoc
))
2384 Check_Can_Never_Be_Null
(Compon
, Expression
(Assoc
));
2387 -- We need to duplicate the expression when several
2388 -- components are grouped together with a "|" choice.
2389 -- For instance "filed1 | filed2 => Expr"
2391 -- Ada 2005 (AI-287)
2393 if Box_Present
(Assoc
) then
2394 Is_Box_Present
:= True;
2396 -- Duplicate the default expression of the component
2397 -- from the record type declaration, so a new copy
2398 -- can be attached to the association.
2400 -- Note that we always copy the default expression,
2401 -- even when the association has a single choice, in
2402 -- order to create a proper association for the
2403 -- expanded aggregate.
2405 Expr
:= New_Copy_Tree
(Expression
(Parent
(Compon
)));
2408 if Present
(Next
(Selector_Name
)) then
2409 Expr
:= New_Copy_Tree
(Expression
(Assoc
));
2411 Expr
:= Expression
(Assoc
);
2415 Generate_Reference
(Compon
, Selector_Name
);
2419 ("more than one value supplied for &",
2420 Selector_Name
, Compon
);
2425 Next
(Selector_Name
);
2434 procedure Check_Non_Limited_Type
(Expr
: Node_Id
);
2435 -- Relax check to allow the default initialization of limited types.
2438 -- C : Lim := (..., others => <>);
2441 ----------------------------
2442 -- Check_Non_Limited_Type --
2443 ----------------------------
2445 procedure Check_Non_Limited_Type
(Expr
: Node_Id
) is
2447 if Is_Limited_Type
(Etype
(Expr
))
2448 and then Comes_From_Source
(Expr
)
2449 and then not In_Instance_Body
2451 if not OK_For_Limited_Init
(Expr
) then
2453 ("initialization not allowed for limited types", N
);
2454 Explain_Limited_Type
(Etype
(Expr
), Expr
);
2457 end Check_Non_Limited_Type
;
2459 -----------------------
2460 -- Resolve_Aggr_Expr --
2461 -----------------------
2463 procedure Resolve_Aggr_Expr
(Expr
: Node_Id
; Component
: Node_Id
) is
2464 New_C
: Entity_Id
:= Component
;
2465 Expr_Type
: Entity_Id
:= Empty
;
2467 function Has_Expansion_Delayed
(Expr
: Node_Id
) return Boolean;
2468 -- If the expression is an aggregate (possibly qualified) then its
2469 -- expansion is delayed until the enclosing aggregate is expanded
2470 -- into assignments. In that case, do not generate checks on the
2471 -- expression, because they will be generated later, and will other-
2472 -- wise force a copy (to remove side-effects) that would leave a
2473 -- dynamic-sized aggregate in the code, something that gigi cannot
2477 -- Set to True if the resolved Expr node needs to be relocated
2478 -- when attached to the newly created association list. This node
2479 -- need not be relocated if its parent pointer is not set.
2480 -- In fact in this case Expr is the output of a New_Copy_Tree call.
2481 -- if Relocate is True then we have analyzed the expression node
2482 -- in the original aggregate and hence it needs to be relocated
2483 -- when moved over the new association list.
2485 function Has_Expansion_Delayed
(Expr
: Node_Id
) return Boolean is
2486 Kind
: constant Node_Kind
:= Nkind
(Expr
);
2489 return ((Kind
= N_Aggregate
2490 or else Kind
= N_Extension_Aggregate
)
2491 and then Present
(Etype
(Expr
))
2492 and then Is_Record_Type
(Etype
(Expr
))
2493 and then Expansion_Delayed
(Expr
))
2495 or else (Kind
= N_Qualified_Expression
2496 and then Has_Expansion_Delayed
(Expression
(Expr
)));
2497 end Has_Expansion_Delayed
;
2499 -- Start of processing for Resolve_Aggr_Expr
2502 -- If the type of the component is elementary or the type of the
2503 -- aggregate does not contain discriminants, use the type of the
2504 -- component to resolve Expr.
2506 if Is_Elementary_Type
(Etype
(Component
))
2507 or else not Has_Discriminants
(Etype
(N
))
2509 Expr_Type
:= Etype
(Component
);
2511 -- Otherwise we have to pick up the new type of the component from
2512 -- the new costrained subtype of the aggregate. In fact components
2513 -- which are of a composite type might be constrained by a
2514 -- discriminant, and we want to resolve Expr against the subtype were
2515 -- all discriminant occurrences are replaced with their actual value.
2518 New_C
:= First_Component
(Etype
(N
));
2519 while Present
(New_C
) loop
2520 if Chars
(New_C
) = Chars
(Component
) then
2521 Expr_Type
:= Etype
(New_C
);
2525 Next_Component
(New_C
);
2528 pragma Assert
(Present
(Expr_Type
));
2530 -- For each range in an array type where a discriminant has been
2531 -- replaced with the constraint, check that this range is within
2532 -- the range of the base type. This checks is done in the init
2533 -- proc for regular objects, but has to be done here for
2534 -- aggregates since no init proc is called for them.
2536 if Is_Array_Type
(Expr_Type
) then
2539 -- Range of the current constrained index in the array
2541 Orig_Index
: Node_Id
:= First_Index
(Etype
(Component
));
2542 -- Range corresponding to the range Index above in the
2543 -- original unconstrained record type. The bounds of this
2544 -- range may be governed by discriminants.
2546 Unconstr_Index
: Node_Id
:= First_Index
(Etype
(Expr_Type
));
2547 -- Range corresponding to the range Index above for the
2548 -- unconstrained array type. This range is needed to apply
2552 Index
:= First_Index
(Expr_Type
);
2553 while Present
(Index
) loop
2554 if Depends_On_Discriminant
(Orig_Index
) then
2555 Apply_Range_Check
(Index
, Etype
(Unconstr_Index
));
2559 Next_Index
(Orig_Index
);
2560 Next_Index
(Unconstr_Index
);
2566 -- If the Parent pointer of Expr is not set, Expr is an expression
2567 -- duplicated by New_Tree_Copy (this happens for record aggregates
2568 -- that look like (Field1 | Filed2 => Expr) or (others => Expr)).
2569 -- Such a duplicated expression must be attached to the tree
2570 -- before analysis and resolution to enforce the rule that a tree
2571 -- fragment should never be analyzed or resolved unless it is
2572 -- attached to the current compilation unit.
2574 if No
(Parent
(Expr
)) then
2575 Set_Parent
(Expr
, N
);
2581 Analyze_And_Resolve
(Expr
, Expr_Type
);
2582 Check_Non_Limited_Type
(Expr
);
2583 Check_Non_Static_Context
(Expr
);
2584 Check_Unset_Reference
(Expr
);
2586 if not Has_Expansion_Delayed
(Expr
) then
2587 Aggregate_Constraint_Checks
(Expr
, Expr_Type
);
2590 if Raises_Constraint_Error
(Expr
) then
2591 Set_Raises_Constraint_Error
(N
);
2595 Add_Association
(New_C
, Relocate_Node
(Expr
));
2597 Add_Association
(New_C
, Expr
);
2599 end Resolve_Aggr_Expr
;
2601 -- Start of processing for Resolve_Record_Aggregate
2604 -- We may end up calling Duplicate_Subexpr on expressions that are
2605 -- attached to New_Assoc_List. For this reason we need to attach it
2606 -- to the tree by setting its parent pointer to N. This parent point
2607 -- will change in STEP 8 below.
2609 Set_Parent
(New_Assoc_List
, N
);
2611 -- STEP 1: abstract type and null record verification
2613 if Is_Abstract_Type
(Typ
) then
2614 Error_Msg_N
("type of aggregate cannot be abstract", N
);
2617 if No
(First_Entity
(Typ
)) and then Null_Record_Present
(N
) then
2621 elsif Present
(First_Entity
(Typ
))
2622 and then Null_Record_Present
(N
)
2623 and then not Is_Tagged_Type
(Typ
)
2625 Error_Msg_N
("record aggregate cannot be null", N
);
2628 elsif No
(First_Entity
(Typ
)) then
2629 Error_Msg_N
("record aggregate must be null", N
);
2633 -- STEP 2: Verify aggregate structure
2636 Selector_Name
: Node_Id
;
2637 Bad_Aggregate
: Boolean := False;
2640 if Present
(Component_Associations
(N
)) then
2641 Assoc
:= First
(Component_Associations
(N
));
2646 while Present
(Assoc
) loop
2647 Selector_Name
:= First
(Choices
(Assoc
));
2648 while Present
(Selector_Name
) loop
2649 if Nkind
(Selector_Name
) = N_Identifier
then
2652 elsif Nkind
(Selector_Name
) = N_Others_Choice
then
2653 if Selector_Name
/= First
(Choices
(Assoc
))
2654 or else Present
(Next
(Selector_Name
))
2656 Error_Msg_N
("OTHERS must appear alone in a choice list",
2660 elsif Present
(Next
(Assoc
)) then
2661 Error_Msg_N
("OTHERS must appear last in an aggregate",
2665 -- (Ada2005): If this is an association with a box,
2666 -- indicate that the association need not represent
2669 elsif Box_Present
(Assoc
) then
2675 ("selector name should be identifier or OTHERS",
2677 Bad_Aggregate
:= True;
2680 Next
(Selector_Name
);
2686 if Bad_Aggregate
then
2691 -- STEP 3: Find discriminant Values
2694 Discrim
: Entity_Id
;
2695 Missing_Discriminants
: Boolean := False;
2698 if Present
(Expressions
(N
)) then
2699 Positional_Expr
:= First
(Expressions
(N
));
2701 Positional_Expr
:= Empty
;
2704 if Has_Discriminants
(Typ
) then
2705 Discrim
:= First_Discriminant
(Typ
);
2710 -- First find the discriminant values in the positional components
2712 while Present
(Discrim
) and then Present
(Positional_Expr
) loop
2713 if Discr_Present
(Discrim
) then
2714 Resolve_Aggr_Expr
(Positional_Expr
, Discrim
);
2716 -- Ada 2005 (AI-231)
2718 if Ada_Version
>= Ada_05
2719 and then Known_Null
(Positional_Expr
)
2721 Check_Can_Never_Be_Null
(Discrim
, Positional_Expr
);
2724 Next
(Positional_Expr
);
2727 if Present
(Get_Value
(Discrim
, Component_Associations
(N
))) then
2729 ("more than one value supplied for discriminant&",
2733 Next_Discriminant
(Discrim
);
2736 -- Find remaining discriminant values, if any, among named components
2738 while Present
(Discrim
) loop
2739 Expr
:= Get_Value
(Discrim
, Component_Associations
(N
), True);
2741 if not Discr_Present
(Discrim
) then
2742 if Present
(Expr
) then
2744 ("more than one value supplied for discriminant&",
2748 elsif No
(Expr
) then
2750 ("no value supplied for discriminant &", N
, Discrim
);
2751 Missing_Discriminants
:= True;
2754 Resolve_Aggr_Expr
(Expr
, Discrim
);
2757 Next_Discriminant
(Discrim
);
2760 if Missing_Discriminants
then
2764 -- At this point and until the beginning of STEP 6, New_Assoc_List
2765 -- contains only the discriminants and their values.
2769 -- STEP 4: Set the Etype of the record aggregate
2771 -- ??? This code is pretty much a copy of Sem_Ch3.Build_Subtype. That
2772 -- routine should really be exported in sem_util or some such and used
2773 -- in sem_ch3 and here rather than have a copy of the code which is a
2774 -- maintenance nightmare.
2776 -- ??? Performace WARNING. The current implementation creates a new
2777 -- itype for all aggregates whose base type is discriminated.
2778 -- This means that for record aggregates nested inside an array
2779 -- aggregate we will create a new itype for each record aggregate
2780 -- if the array cmponent type has discriminants. For large aggregates
2781 -- this may be a problem. What should be done in this case is
2782 -- to reuse itypes as much as possible.
2784 if Has_Discriminants
(Typ
) then
2785 Build_Constrained_Itype
: declare
2786 Loc
: constant Source_Ptr
:= Sloc
(N
);
2788 Subtyp_Decl
: Node_Id
;
2791 C
: constant List_Id
:= New_List
;
2794 New_Assoc
:= First
(New_Assoc_List
);
2795 while Present
(New_Assoc
) loop
2796 Append
(Duplicate_Subexpr
(Expression
(New_Assoc
)), To
=> C
);
2801 Make_Subtype_Indication
(Loc
,
2802 Subtype_Mark
=> New_Occurrence_Of
(Base_Type
(Typ
), Loc
),
2803 Constraint
=> Make_Index_Or_Discriminant_Constraint
(Loc
, C
));
2805 Def_Id
:= Create_Itype
(Ekind
(Typ
), N
);
2808 Make_Subtype_Declaration
(Loc
,
2809 Defining_Identifier
=> Def_Id
,
2810 Subtype_Indication
=> Indic
);
2811 Set_Parent
(Subtyp_Decl
, Parent
(N
));
2813 -- Itypes must be analyzed with checks off (see itypes.ads)
2815 Analyze
(Subtyp_Decl
, Suppress
=> All_Checks
);
2817 Set_Etype
(N
, Def_Id
);
2818 Check_Static_Discriminated_Subtype
2819 (Def_Id
, Expression
(First
(New_Assoc_List
)));
2820 end Build_Constrained_Itype
;
2826 -- STEP 5: Get remaining components according to discriminant values
2829 Record_Def
: Node_Id
;
2830 Parent_Typ
: Entity_Id
;
2831 Root_Typ
: Entity_Id
;
2832 Parent_Typ_List
: Elist_Id
;
2833 Parent_Elmt
: Elmt_Id
;
2834 Errors_Found
: Boolean := False;
2838 if Is_Derived_Type
(Typ
) and then Is_Tagged_Type
(Typ
) then
2839 Parent_Typ_List
:= New_Elmt_List
;
2841 -- If this is an extension aggregate, the component list must
2842 -- include all components that are not in the given ancestor
2843 -- type. Otherwise, the component list must include components
2844 -- of all ancestors, starting with the root.
2846 if Nkind
(N
) = N_Extension_Aggregate
then
2847 Root_Typ
:= Base_Type
(Etype
(Ancestor_Part
(N
)));
2849 Root_Typ
:= Root_Type
(Typ
);
2851 if Nkind
(Parent
(Base_Type
(Root_Typ
)))
2852 = N_Private_Type_Declaration
2855 ("type of aggregate has private ancestor&!",
2857 Error_Msg_N
("must use extension aggregate!", N
);
2861 Dnode
:= Declaration_Node
(Base_Type
(Root_Typ
));
2863 -- If we don't get a full declaration, then we have some
2864 -- error which will get signalled later so skip this part.
2865 -- Otherwise, gather components of root that apply to the
2866 -- aggregate type. We use the base type in case there is an
2867 -- applicable stored constraint that renames the discriminants
2870 if Nkind
(Dnode
) = N_Full_Type_Declaration
then
2871 Record_Def
:= Type_Definition
(Dnode
);
2872 Gather_Components
(Base_Type
(Typ
),
2873 Component_List
(Record_Def
),
2874 Governed_By
=> New_Assoc_List
,
2876 Report_Errors
=> Errors_Found
);
2880 Parent_Typ
:= Base_Type
(Typ
);
2881 while Parent_Typ
/= Root_Typ
loop
2882 Prepend_Elmt
(Parent_Typ
, To
=> Parent_Typ_List
);
2883 Parent_Typ
:= Etype
(Parent_Typ
);
2885 if Nkind
(Parent
(Base_Type
(Parent_Typ
))) =
2886 N_Private_Type_Declaration
2887 or else Nkind
(Parent
(Base_Type
(Parent_Typ
))) =
2888 N_Private_Extension_Declaration
2890 if Nkind
(N
) /= N_Extension_Aggregate
then
2892 ("type of aggregate has private ancestor&!",
2894 Error_Msg_N
("must use extension aggregate!", N
);
2897 elsif Parent_Typ
/= Root_Typ
then
2899 ("ancestor part of aggregate must be private type&",
2900 Ancestor_Part
(N
), Parent_Typ
);
2906 -- Now collect components from all other ancestors
2908 Parent_Elmt
:= First_Elmt
(Parent_Typ_List
);
2909 while Present
(Parent_Elmt
) loop
2910 Parent_Typ
:= Node
(Parent_Elmt
);
2911 Record_Def
:= Type_Definition
(Parent
(Base_Type
(Parent_Typ
)));
2912 Gather_Components
(Empty
,
2913 Component_List
(Record_Extension_Part
(Record_Def
)),
2914 Governed_By
=> New_Assoc_List
,
2916 Report_Errors
=> Errors_Found
);
2918 Next_Elmt
(Parent_Elmt
);
2922 Record_Def
:= Type_Definition
(Parent
(Base_Type
(Typ
)));
2924 if Null_Present
(Record_Def
) then
2927 Gather_Components
(Base_Type
(Typ
),
2928 Component_List
(Record_Def
),
2929 Governed_By
=> New_Assoc_List
,
2931 Report_Errors
=> Errors_Found
);
2935 if Errors_Found
then
2940 -- STEP 6: Find component Values
2943 Component_Elmt
:= First_Elmt
(Components
);
2945 -- First scan the remaining positional associations in the aggregate.
2946 -- Remember that at this point Positional_Expr contains the current
2947 -- positional association if any is left after looking for discriminant
2948 -- values in step 3.
2950 while Present
(Positional_Expr
) and then Present
(Component_Elmt
) loop
2951 Component
:= Node
(Component_Elmt
);
2952 Resolve_Aggr_Expr
(Positional_Expr
, Component
);
2954 -- Ada 2005 (AI-231)
2956 if Ada_Version
>= Ada_05
2957 and then Known_Null
(Positional_Expr
)
2959 Check_Can_Never_Be_Null
(Component
, Positional_Expr
);
2962 if Present
(Get_Value
(Component
, Component_Associations
(N
))) then
2964 ("more than one value supplied for Component &", N
, Component
);
2967 Next
(Positional_Expr
);
2968 Next_Elmt
(Component_Elmt
);
2971 if Present
(Positional_Expr
) then
2973 ("too many components for record aggregate", Positional_Expr
);
2976 -- Now scan for the named arguments of the aggregate
2978 while Present
(Component_Elmt
) loop
2979 Component
:= Node
(Component_Elmt
);
2980 Expr
:= Get_Value
(Component
, Component_Associations
(N
), True);
2982 -- Note: The previous call to Get_Value sets the value of the
2983 -- variable Is_Box_Present.
2985 -- Ada 2005 (AI-287): Handle components with default initialization.
2986 -- Note: This feature was originally added to Ada 2005 for limited
2987 -- but it was finally allowed with any type.
2989 if Is_Box_Present
then
2990 Check_Box_Component
: declare
2991 Ctyp
: constant Entity_Id
:= Etype
(Component
);
2994 -- If there is a default expression for the aggregate, copy
2995 -- it into a new association.
2997 -- If the component has an initialization procedure (IP) we
2998 -- pass the component to the expander, which will generate
2999 -- the call to such IP.
3001 -- If the component has discriminants, their values must
3002 -- be taken from their subtype. This is indispensable for
3003 -- constraints that are given by the current instance of an
3004 -- enclosing type, to allow the expansion of the aggregate
3005 -- to replace the reference to the current instance by the
3006 -- target object of the aggregate.
3008 if Present
(Parent
(Component
))
3010 Nkind
(Parent
(Component
)) = N_Component_Declaration
3011 and then Present
(Expression
(Parent
(Component
)))
3014 New_Copy_Tree
(Expression
(Parent
(Component
)),
3015 New_Sloc
=> Sloc
(N
));
3018 (Component
=> Component
,
3020 Set_Has_Self_Reference
(N
);
3022 -- A box-defaulted access component gets the value null. Also
3023 -- included are components of private types whose underlying
3024 -- type is an access type. In either case set the type of the
3025 -- literal, for subsequent use in semantic checks.
3027 elsif Present
(Underlying_Type
(Ctyp
))
3028 and then Is_Access_Type
(Underlying_Type
(Ctyp
))
3030 if not Is_Private_Type
(Ctyp
) then
3031 Expr
:= Make_Null
(Sloc
(N
));
3032 Set_Etype
(Expr
, Ctyp
);
3034 (Component
=> Component
,
3037 -- If the component's type is private with an access type as
3038 -- its underlying type then we have to create an unchecked
3039 -- conversion to satisfy type checking.
3043 Qual_Null
: constant Node_Id
:=
3044 Make_Qualified_Expression
(Sloc
(N
),
3047 (Underlying_Type
(Ctyp
), Sloc
(N
)),
3048 Expression
=> Make_Null
(Sloc
(N
)));
3050 Convert_Null
: constant Node_Id
:=
3051 Unchecked_Convert_To
3055 Analyze_And_Resolve
(Convert_Null
, Ctyp
);
3057 (Component
=> Component
, Expr
=> Convert_Null
);
3061 elsif Has_Non_Null_Base_Init_Proc
(Ctyp
)
3062 or else not Expander_Active
3064 if Is_Record_Type
(Ctyp
)
3065 and then Has_Discriminants
(Ctyp
)
3067 -- We build a partially initialized aggregate with the
3068 -- values of the discriminants and box initialization
3069 -- for the rest, if other components are present.
3072 Loc
: constant Source_Ptr
:= Sloc
(N
);
3075 Discr_Elmt
: Elmt_Id
;
3076 Discr_Val
: Node_Id
;
3080 Expr
:= Make_Aggregate
(Loc
, New_List
, New_List
);
3083 First_Elmt
(Discriminant_Constraint
(Ctyp
));
3084 while Present
(Discr_Elmt
) loop
3085 Discr_Val
:= Node
(Discr_Elmt
);
3087 -- The constraint may be given by a discriminant
3088 -- of the enclosing type, in which case we have
3089 -- to retrieve its value, which is part of the
3090 -- current aggregate.
3092 if Is_Entity_Name
(Discr_Val
)
3094 Ekind
(Entity
(Discr_Val
)) = E_Discriminant
3096 Discr
:= Entity
(Discr_Val
);
3098 Assoc
:= First
(New_Assoc_List
);
3099 while Present
(Assoc
) loop
3101 (Entity
(First
(Choices
(Assoc
))))
3103 Entity
(First
(Choices
(Assoc
))) = Discr
3105 Discr_Val
:= Expression
(Assoc
);
3113 (New_Copy_Tree
(Discr_Val
), Expressions
(Expr
));
3115 -- If the discriminant constraint is a current
3116 -- instance, mark the current aggregate so that
3117 -- the self-reference can be expanded later.
3119 if Nkind
(Discr_Val
) = N_Attribute_Reference
3120 and then Is_Entity_Name
(Prefix
(Discr_Val
))
3121 and then Is_Type
(Entity
(Prefix
(Discr_Val
)))
3122 and then Etype
(N
) = Entity
(Prefix
(Discr_Val
))
3124 Set_Has_Self_Reference
(N
);
3127 Next_Elmt
(Discr_Elmt
);
3134 -- Look for a component that is not a discriminant
3135 -- before creating an others box association.
3137 Comp
:= First_Component
(Ctyp
);
3138 while Present
(Comp
) loop
3139 if Ekind
(Comp
) = E_Component
then
3141 (Make_Component_Association
(Loc
,
3143 New_List
(Make_Others_Choice
(Loc
)),
3144 Expression
=> Empty
,
3145 Box_Present
=> True),
3146 Component_Associations
(Expr
));
3150 Next_Component
(Comp
);
3155 (Component
=> Component
,
3161 (Component
=> Component
,
3163 Is_Box_Present
=> True);
3166 -- Otherwise we only need to resolve the expression if the
3167 -- component has partially initialized values (required to
3168 -- expand the corresponding assignments and run-time checks).
3170 elsif Present
(Expr
)
3171 and then Is_Partially_Initialized_Type
(Ctyp
)
3173 Resolve_Aggr_Expr
(Expr
, Component
);
3175 end Check_Box_Component
;
3177 elsif No
(Expr
) then
3179 -- Ignore hidden components associated with the position of the
3180 -- interface tags: these are initialized dynamically.
3182 if not Present
(Related_Type
(Component
)) then
3184 ("no value supplied for component &!", N
, Component
);
3188 Resolve_Aggr_Expr
(Expr
, Component
);
3191 Next_Elmt
(Component_Elmt
);
3194 -- STEP 7: check for invalid components + check type in choice list
3201 -- Type of first component in choice list
3204 if Present
(Component_Associations
(N
)) then
3205 Assoc
:= First
(Component_Associations
(N
));
3210 Verification
: while Present
(Assoc
) loop
3211 Selectr
:= First
(Choices
(Assoc
));
3214 if Nkind
(Selectr
) = N_Others_Choice
then
3216 -- Ada 2005 (AI-287): others choice may have expression or box
3218 if No
(Others_Etype
)
3219 and then not Others_Box
3222 ("OTHERS must represent at least one component", Selectr
);
3228 while Present
(Selectr
) loop
3229 New_Assoc
:= First
(New_Assoc_List
);
3230 while Present
(New_Assoc
) loop
3231 Component
:= First
(Choices
(New_Assoc
));
3232 exit when Chars
(Selectr
) = Chars
(Component
);
3236 -- If no association, this is not a legal component of
3237 -- of the type in question, except if its association
3238 -- is provided with a box.
3240 if No
(New_Assoc
) then
3241 if Box_Present
(Parent
(Selectr
)) then
3243 -- This may still be a bogus component with a box. Scan
3244 -- list of components to verify that a component with
3245 -- that name exists.
3251 C
:= First_Component
(Typ
);
3252 while Present
(C
) loop
3253 if Chars
(C
) = Chars
(Selectr
) then
3261 Error_Msg_Node_2
:= Typ
;
3262 Error_Msg_N
("& is not a component of}", Selectr
);
3266 elsif Chars
(Selectr
) /= Name_uTag
3267 and then Chars
(Selectr
) /= Name_uParent
3268 and then Chars
(Selectr
) /= Name_uController
3270 if not Has_Discriminants
(Typ
) then
3271 Error_Msg_Node_2
:= Typ
;
3272 Error_Msg_N
("& is not a component of}", Selectr
);
3275 ("& is not a component of the aggregate subtype",
3279 Check_Misspelled_Component
(Components
, Selectr
);
3282 elsif No
(Typech
) then
3283 Typech
:= Base_Type
(Etype
(Component
));
3285 elsif Typech
/= Base_Type
(Etype
(Component
)) then
3286 if not Box_Present
(Parent
(Selectr
)) then
3288 ("components in choice list must have same type",
3297 end loop Verification
;
3300 -- STEP 8: replace the original aggregate
3303 New_Aggregate
: constant Node_Id
:= New_Copy
(N
);
3306 Set_Expressions
(New_Aggregate
, No_List
);
3307 Set_Etype
(New_Aggregate
, Etype
(N
));
3308 Set_Component_Associations
(New_Aggregate
, New_Assoc_List
);
3310 Rewrite
(N
, New_Aggregate
);
3312 end Resolve_Record_Aggregate
;
3314 -----------------------------
3315 -- Check_Can_Never_Be_Null --
3316 -----------------------------
3318 procedure Check_Can_Never_Be_Null
(Typ
: Entity_Id
; Expr
: Node_Id
) is
3319 Comp_Typ
: Entity_Id
;
3323 (Ada_Version
>= Ada_05
3324 and then Present
(Expr
)
3325 and then Known_Null
(Expr
));
3328 when E_Array_Type
=>
3329 Comp_Typ
:= Component_Type
(Typ
);
3333 Comp_Typ
:= Etype
(Typ
);
3339 if Can_Never_Be_Null
(Comp_Typ
) then
3341 -- Here we know we have a constraint error. Note that we do not use
3342 -- Apply_Compile_Time_Constraint_Error here to the Expr, which might
3343 -- seem the more natural approach. That's because in some cases the
3344 -- components are rewritten, and the replacement would be missed.
3347 (Compile_Time_Constraint_Error
3349 "(Ada 2005) null not allowed in null-excluding component?"),
3350 Make_Raise_Constraint_Error
(Sloc
(Expr
),
3351 Reason
=> CE_Access_Check_Failed
));
3353 -- Set proper type for bogus component (why is this needed???)
3355 Set_Etype
(Expr
, Comp_Typ
);
3356 Set_Analyzed
(Expr
);
3358 end Check_Can_Never_Be_Null
;
3360 ---------------------
3361 -- Sort_Case_Table --
3362 ---------------------
3364 procedure Sort_Case_Table
(Case_Table
: in out Case_Table_Type
) is
3365 L
: constant Int
:= Case_Table
'First;
3366 U
: constant Int
:= Case_Table
'Last;
3374 T
:= Case_Table
(K
+ 1);
3378 and then Expr_Value
(Case_Table
(J
- 1).Choice_Lo
) >
3379 Expr_Value
(T
.Choice_Lo
)
3381 Case_Table
(J
) := Case_Table
(J
- 1);
3385 Case_Table
(J
) := T
;
3388 end Sort_Case_Table
;