1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2017, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Aspects
; use Aspects
;
27 with Atree
; use Atree
;
28 with Checks
; use Checks
;
29 with Einfo
; use Einfo
;
30 with Elists
; use Elists
;
31 with Errout
; use Errout
;
32 with Expander
; use Expander
;
33 with Exp_Tss
; use Exp_Tss
;
34 with Exp_Util
; use Exp_Util
;
35 with Freeze
; use Freeze
;
36 with Itypes
; use Itypes
;
38 with Lib
.Xref
; use Lib
.Xref
;
39 with Namet
; use Namet
;
40 with Namet
.Sp
; use Namet
.Sp
;
41 with Nmake
; use Nmake
;
42 with Nlists
; use Nlists
;
44 with Restrict
; use Restrict
;
45 with Rident
; use Rident
;
47 with Sem_Aux
; use Sem_Aux
;
48 with Sem_Cat
; use Sem_Cat
;
49 with Sem_Ch3
; use Sem_Ch3
;
50 with Sem_Ch8
; use Sem_Ch8
;
51 with Sem_Ch13
; use Sem_Ch13
;
52 with Sem_Dim
; use Sem_Dim
;
53 with Sem_Eval
; use Sem_Eval
;
54 with Sem_Res
; use Sem_Res
;
55 with Sem_Util
; use Sem_Util
;
56 with Sem_Type
; use Sem_Type
;
57 with Sem_Warn
; use Sem_Warn
;
58 with Sinfo
; use Sinfo
;
59 with Snames
; use Snames
;
60 with Stringt
; use Stringt
;
61 with Stand
; use Stand
;
62 with Style
; use Style
;
63 with Targparm
; use Targparm
;
64 with Tbuild
; use Tbuild
;
65 with Uintp
; use Uintp
;
67 package body Sem_Aggr
is
69 type Case_Bounds
is record
71 -- Low bound of choice. Once we sort the Case_Table, then entries
72 -- will be in order of ascending Choice_Lo values.
75 -- High Bound of choice. The sort does not pay any attention to the
76 -- high bound, so choices 1 .. 4 and 1 .. 5 could be in either order.
79 -- If there are duplicates or missing entries, then in the sorted
80 -- table, this records the highest value among Choice_Hi values
81 -- seen so far, including this entry.
84 -- The node of the choice
87 type Case_Table_Type
is array (Nat
range <>) of Case_Bounds
;
88 -- Table type used by Check_Case_Choices procedure. Entry zero is not
89 -- used (reserved for the sort). Real entries start at one.
91 -----------------------
92 -- Local Subprograms --
93 -----------------------
95 procedure Sort_Case_Table
(Case_Table
: in out Case_Table_Type
);
96 -- Sort the Case Table using the Lower Bound of each Choice as the key. A
97 -- simple insertion sort is used since the choices in a case statement will
98 -- usually be in near sorted order.
100 procedure Check_Can_Never_Be_Null
(Typ
: Entity_Id
; Expr
: Node_Id
);
101 -- Ada 2005 (AI-231): Check bad usage of null for a component for which
102 -- null exclusion (NOT NULL) is specified. Typ can be an E_Array_Type for
103 -- the array case (the component type of the array will be used) or an
104 -- E_Component/E_Discriminant entity in the record case, in which case the
105 -- type of the component will be used for the test. If Typ is any other
106 -- kind of entity, the call is ignored. Expr is the component node in the
107 -- aggregate which is known to have a null value. A warning message will be
108 -- issued if the component is null excluding.
110 -- It would be better to pass the proper type for Typ ???
112 procedure Check_Expr_OK_In_Limited_Aggregate
(Expr
: Node_Id
);
113 -- Check that Expr is either not limited or else is one of the cases of
114 -- expressions allowed for a limited component association (namely, an
115 -- aggregate, function call, or <> notation). Report error for violations.
116 -- Expression is also OK in an instance or inlining context, because we
117 -- have already pre-analyzed and it is known to be type correct.
119 procedure Check_Qualified_Aggregate
(Level
: Nat
; Expr
: Node_Id
);
120 -- Given aggregate Expr, check that sub-aggregates of Expr that are nested
121 -- at Level are qualified. If Level = 0, this applies to Expr directly.
122 -- Only issue errors in formal verification mode.
124 function Is_Top_Level_Aggregate
(Expr
: Node_Id
) return Boolean;
125 -- Return True of Expr is an aggregate not contained directly in another
128 ------------------------------------------------------
129 -- Subprograms used for RECORD AGGREGATE Processing --
130 ------------------------------------------------------
132 procedure Resolve_Record_Aggregate
(N
: Node_Id
; Typ
: Entity_Id
);
133 -- This procedure performs all the semantic checks required for record
134 -- aggregates. Note that for aggregates analysis and resolution go
135 -- hand in hand. Aggregate analysis has been delayed up to here and
136 -- it is done while resolving the aggregate.
138 -- N is the N_Aggregate node.
139 -- Typ is the record type for the aggregate resolution
141 -- While performing the semantic checks, this procedure builds a new
142 -- Component_Association_List where each record field appears alone in a
143 -- Component_Choice_List along with its corresponding expression. The
144 -- record fields in the Component_Association_List appear in the same order
145 -- in which they appear in the record type Typ.
147 -- Once this new Component_Association_List is built and all the semantic
148 -- checks performed, the original aggregate subtree is replaced with the
149 -- new named record aggregate just built. Note that subtree substitution is
150 -- performed with Rewrite so as to be able to retrieve the original
153 -- The aggregate subtree manipulation performed by Resolve_Record_Aggregate
154 -- yields the aggregate format expected by Gigi. Typically, this kind of
155 -- tree manipulations are done in the expander. However, because the
156 -- semantic checks that need to be performed on record aggregates really go
157 -- hand in hand with the record aggregate normalization, the aggregate
158 -- subtree transformation is performed during resolution rather than
159 -- expansion. Had we decided otherwise we would have had to duplicate most
160 -- of the code in the expansion procedure Expand_Record_Aggregate. Note,
161 -- however, that all the expansion concerning aggregates for tagged records
162 -- is done in Expand_Record_Aggregate.
164 -- The algorithm of Resolve_Record_Aggregate proceeds as follows:
166 -- 1. Make sure that the record type against which the record aggregate
167 -- has to be resolved is not abstract. Furthermore if the type is a
168 -- null aggregate make sure the input aggregate N is also null.
170 -- 2. Verify that the structure of the aggregate is that of a record
171 -- aggregate. Specifically, look for component associations and ensure
172 -- that each choice list only has identifiers or the N_Others_Choice
173 -- node. Also make sure that if present, the N_Others_Choice occurs
174 -- last and by itself.
176 -- 3. If Typ contains discriminants, the values for each discriminant is
177 -- looked for. If the record type Typ has variants, we check that the
178 -- expressions corresponding to each discriminant ruling the (possibly
179 -- nested) variant parts of Typ, are static. This allows us to determine
180 -- the variant parts to which the rest of the aggregate must conform.
181 -- The names of discriminants with their values are saved in a new
182 -- association list, New_Assoc_List which is later augmented with the
183 -- names and values of the remaining components in the record type.
185 -- During this phase we also make sure that every discriminant is
186 -- assigned exactly one value. Note that when several values for a given
187 -- discriminant are found, semantic processing continues looking for
188 -- further errors. In this case it's the first discriminant value found
189 -- which we will be recorded.
191 -- IMPORTANT NOTE: For derived tagged types this procedure expects
192 -- First_Discriminant and Next_Discriminant to give the correct list
193 -- of discriminants, in the correct order.
195 -- 4. After all the discriminant values have been gathered, we can set the
196 -- Etype of the record aggregate. If Typ contains no discriminants this
197 -- is straightforward: the Etype of N is just Typ, otherwise a new
198 -- implicit constrained subtype of Typ is built to be the Etype of N.
200 -- 5. Gather the remaining record components according to the discriminant
201 -- values. This involves recursively traversing the record type
202 -- structure to see what variants are selected by the given discriminant
203 -- values. This processing is a little more convoluted if Typ is a
204 -- derived tagged types since we need to retrieve the record structure
205 -- of all the ancestors of Typ.
207 -- 6. After gathering the record components we look for their values in the
208 -- record aggregate and emit appropriate error messages should we not
209 -- find such values or should they be duplicated.
211 -- 7. We then make sure no illegal component names appear in the record
212 -- aggregate and make sure that the type of the record components
213 -- appearing in a same choice list is the same. Finally we ensure that
214 -- the others choice, if present, is used to provide the value of at
215 -- least a record component.
217 -- 8. The original aggregate node is replaced with the new named aggregate
218 -- built in steps 3 through 6, as explained earlier.
220 -- Given the complexity of record aggregate resolution, the primary goal of
221 -- this routine is clarity and simplicity rather than execution and storage
222 -- efficiency. If there are only positional components in the aggregate the
223 -- running time is linear. If there are associations the running time is
224 -- still linear as long as the order of the associations is not too far off
225 -- the order of the components in the record type. If this is not the case
226 -- the running time is at worst quadratic in the size of the association
229 procedure Check_Misspelled_Component
230 (Elements
: Elist_Id
;
231 Component
: Node_Id
);
232 -- Give possible misspelling diagnostic if Component is likely to be a
233 -- misspelling of one of the components of the Assoc_List. This is called
234 -- by Resolve_Aggr_Expr after producing an invalid component error message.
236 procedure Check_Static_Discriminated_Subtype
(T
: Entity_Id
; V
: Node_Id
);
237 -- An optimization: determine whether a discriminated subtype has a static
238 -- constraint, and contains array components whose length is also static,
239 -- either because they are constrained by the discriminant, or because the
240 -- original component bounds are static.
242 -----------------------------------------------------
243 -- Subprograms used for ARRAY AGGREGATE Processing --
244 -----------------------------------------------------
246 function Resolve_Array_Aggregate
249 Index_Constr
: Node_Id
;
250 Component_Typ
: Entity_Id
;
251 Others_Allowed
: Boolean) return Boolean;
252 -- This procedure performs the semantic checks for an array aggregate.
253 -- True is returned if the aggregate resolution succeeds.
255 -- The procedure works by recursively checking each nested aggregate.
256 -- Specifically, after checking a sub-aggregate nested at the i-th level
257 -- we recursively check all the subaggregates at the i+1-st level (if any).
258 -- Note that for aggregates analysis and resolution go hand in hand.
259 -- Aggregate analysis has been delayed up to here and it is done while
260 -- resolving the aggregate.
262 -- N is the current N_Aggregate node to be checked.
264 -- Index is the index node corresponding to the array sub-aggregate that
265 -- we are currently checking (RM 4.3.3 (8)). Its Etype is the
266 -- corresponding index type (or subtype).
268 -- Index_Constr is the node giving the applicable index constraint if
269 -- any (RM 4.3.3 (10)). It "is a constraint provided by certain
270 -- contexts [...] that can be used to determine the bounds of the array
271 -- value specified by the aggregate". If Others_Allowed below is False
272 -- there is no applicable index constraint and this node is set to Index.
274 -- Component_Typ is the array component type.
276 -- Others_Allowed indicates whether an others choice is allowed
277 -- in the context where the top-level aggregate appeared.
279 -- The algorithm of Resolve_Array_Aggregate proceeds as follows:
281 -- 1. Make sure that the others choice, if present, is by itself and
282 -- appears last in the sub-aggregate. Check that we do not have
283 -- positional and named components in the array sub-aggregate (unless
284 -- the named association is an others choice). Finally if an others
285 -- choice is present, make sure it is allowed in the aggregate context.
287 -- 2. If the array sub-aggregate contains discrete_choices:
289 -- (A) Verify their validity. Specifically verify that:
291 -- (a) If a null range is present it must be the only possible
292 -- choice in the array aggregate.
294 -- (b) Ditto for a non static range.
296 -- (c) Ditto for a non static expression.
298 -- In addition this step analyzes and resolves each discrete_choice,
299 -- making sure that its type is the type of the corresponding Index.
300 -- If we are not at the lowest array aggregate level (in the case of
301 -- multi-dimensional aggregates) then invoke Resolve_Array_Aggregate
302 -- recursively on each component expression. Otherwise, resolve the
303 -- bottom level component expressions against the expected component
304 -- type ONLY IF the component corresponds to a single discrete choice
305 -- which is not an others choice (to see why read the DELAYED
306 -- COMPONENT RESOLUTION below).
308 -- (B) Determine the bounds of the sub-aggregate and lowest and
309 -- highest choice values.
311 -- 3. For positional aggregates:
313 -- (A) Loop over the component expressions either recursively invoking
314 -- Resolve_Array_Aggregate on each of these for multi-dimensional
315 -- array aggregates or resolving the bottom level component
316 -- expressions against the expected component type.
318 -- (B) Determine the bounds of the positional sub-aggregates.
320 -- 4. Try to determine statically whether the evaluation of the array
321 -- sub-aggregate raises Constraint_Error. If yes emit proper
322 -- warnings. The precise checks are the following:
324 -- (A) Check that the index range defined by aggregate bounds is
325 -- compatible with corresponding index subtype.
326 -- We also check against the base type. In fact it could be that
327 -- Low/High bounds of the base type are static whereas those of
328 -- the index subtype are not. Thus if we can statically catch
329 -- a problem with respect to the base type we are guaranteed
330 -- that the same problem will arise with the index subtype
332 -- (B) If we are dealing with a named aggregate containing an others
333 -- choice and at least one discrete choice then make sure the range
334 -- specified by the discrete choices does not overflow the
335 -- aggregate bounds. We also check against the index type and base
336 -- type bounds for the same reasons given in (A).
338 -- (C) If we are dealing with a positional aggregate with an others
339 -- choice make sure the number of positional elements specified
340 -- does not overflow the aggregate bounds. We also check against
341 -- the index type and base type bounds as mentioned in (A).
343 -- Finally construct an N_Range node giving the sub-aggregate bounds.
344 -- Set the Aggregate_Bounds field of the sub-aggregate to be this
345 -- N_Range. The routine Array_Aggr_Subtype below uses such N_Ranges
346 -- to build the appropriate aggregate subtype. Aggregate_Bounds
347 -- information is needed during expansion.
349 -- DELAYED COMPONENT RESOLUTION: The resolution of bottom level component
350 -- expressions in an array aggregate may call Duplicate_Subexpr or some
351 -- other routine that inserts code just outside the outermost aggregate.
352 -- If the array aggregate contains discrete choices or an others choice,
353 -- this may be wrong. Consider for instance the following example.
355 -- type Rec is record
359 -- type Acc_Rec is access Rec;
360 -- Arr : array (1..3) of Acc_Rec := (1 .. 3 => new Rec);
362 -- Then the transformation of "new Rec" that occurs during resolution
363 -- entails the following code modifications
365 -- P7b : constant Acc_Rec := new Rec;
367 -- Arr : array (1..3) of Acc_Rec := (1 .. 3 => P7b);
369 -- This code transformation is clearly wrong, since we need to call
370 -- "new Rec" for each of the 3 array elements. To avoid this problem we
371 -- delay resolution of the components of non positional array aggregates
372 -- to the expansion phase. As an optimization, if the discrete choice
373 -- specifies a single value we do not delay resolution.
375 function Array_Aggr_Subtype
(N
: Node_Id
; Typ
: Node_Id
) return Entity_Id
;
376 -- This routine returns the type or subtype of an array aggregate.
378 -- N is the array aggregate node whose type we return.
380 -- Typ is the context type in which N occurs.
382 -- This routine creates an implicit array subtype whose bounds are
383 -- those defined by the aggregate. When this routine is invoked
384 -- Resolve_Array_Aggregate has already processed aggregate N. Thus the
385 -- Aggregate_Bounds of each sub-aggregate, is an N_Range node giving the
386 -- sub-aggregate bounds. When building the aggregate itype, this function
387 -- traverses the array aggregate N collecting such Aggregate_Bounds and
388 -- constructs the proper array aggregate itype.
390 -- Note that in the case of multidimensional aggregates each inner
391 -- sub-aggregate corresponding to a given array dimension, may provide a
392 -- different bounds. If it is possible to determine statically that
393 -- some sub-aggregates corresponding to the same index do not have the
394 -- same bounds, then a warning is emitted. If such check is not possible
395 -- statically (because some sub-aggregate bounds are dynamic expressions)
396 -- then this job is left to the expander. In all cases the particular
397 -- bounds that this function will chose for a given dimension is the first
398 -- N_Range node for a sub-aggregate corresponding to that dimension.
400 -- Note that the Raises_Constraint_Error flag of an array aggregate
401 -- whose evaluation is determined to raise CE by Resolve_Array_Aggregate,
402 -- is set in Resolve_Array_Aggregate but the aggregate is not
403 -- immediately replaced with a raise CE. In fact, Array_Aggr_Subtype must
404 -- first construct the proper itype for the aggregate (Gigi needs
405 -- this). After constructing the proper itype we will eventually replace
406 -- the top-level aggregate with a raise CE (done in Resolve_Aggregate).
407 -- Of course in cases such as:
409 -- type Arr is array (integer range <>) of Integer;
410 -- A : Arr := (positive range -1 .. 2 => 0);
412 -- The bounds of the aggregate itype are cooked up to look reasonable
413 -- (in this particular case the bounds will be 1 .. 2).
415 procedure Make_String_Into_Aggregate
(N
: Node_Id
);
416 -- A string literal can appear in a context in which a one dimensional
417 -- array of characters is expected. This procedure simply rewrites the
418 -- string as an aggregate, prior to resolution.
420 ------------------------
421 -- Array_Aggr_Subtype --
422 ------------------------
424 function Array_Aggr_Subtype
426 Typ
: Entity_Id
) return Entity_Id
428 Aggr_Dimension
: constant Pos
:= Number_Dimensions
(Typ
);
429 -- Number of aggregate index dimensions
431 Aggr_Range
: array (1 .. Aggr_Dimension
) of Node_Id
:= (others => Empty
);
432 -- Constrained N_Range of each index dimension in our aggregate itype
434 Aggr_Low
: array (1 .. Aggr_Dimension
) of Node_Id
:= (others => Empty
);
435 Aggr_High
: array (1 .. Aggr_Dimension
) of Node_Id
:= (others => Empty
);
436 -- Low and High bounds for each index dimension in our aggregate itype
438 Is_Fully_Positional
: Boolean := True;
440 procedure Collect_Aggr_Bounds
(N
: Node_Id
; Dim
: Pos
);
441 -- N is an array (sub-)aggregate. Dim is the dimension corresponding
442 -- to (sub-)aggregate N. This procedure collects and removes the side
443 -- effects of the constrained N_Range nodes corresponding to each index
444 -- dimension of our aggregate itype. These N_Range nodes are collected
445 -- in Aggr_Range above.
447 -- Likewise collect in Aggr_Low & Aggr_High above the low and high
448 -- bounds of each index dimension. If, when collecting, two bounds
449 -- corresponding to the same dimension are static and found to differ,
450 -- then emit a warning, and mark N as raising Constraint_Error.
452 -------------------------
453 -- Collect_Aggr_Bounds --
454 -------------------------
456 procedure Collect_Aggr_Bounds
(N
: Node_Id
; Dim
: Pos
) is
457 This_Range
: constant Node_Id
:= Aggregate_Bounds
(N
);
458 -- The aggregate range node of this specific sub-aggregate
460 This_Low
: constant Node_Id
:= Low_Bound
(Aggregate_Bounds
(N
));
461 This_High
: constant Node_Id
:= High_Bound
(Aggregate_Bounds
(N
));
462 -- The aggregate bounds of this specific sub-aggregate
468 Remove_Side_Effects
(This_Low
, Variable_Ref
=> True);
469 Remove_Side_Effects
(This_High
, Variable_Ref
=> True);
471 -- Collect the first N_Range for a given dimension that you find.
472 -- For a given dimension they must be all equal anyway.
474 if No
(Aggr_Range
(Dim
)) then
475 Aggr_Low
(Dim
) := This_Low
;
476 Aggr_High
(Dim
) := This_High
;
477 Aggr_Range
(Dim
) := This_Range
;
480 if Compile_Time_Known_Value
(This_Low
) then
481 if not Compile_Time_Known_Value
(Aggr_Low
(Dim
)) then
482 Aggr_Low
(Dim
) := This_Low
;
484 elsif Expr_Value
(This_Low
) /= Expr_Value
(Aggr_Low
(Dim
)) then
485 Set_Raises_Constraint_Error
(N
);
486 Error_Msg_Warn
:= SPARK_Mode
/= On
;
487 Error_Msg_N
("sub-aggregate low bound mismatch<<", N
);
488 Error_Msg_N
("\Constraint_Error [<<", N
);
492 if Compile_Time_Known_Value
(This_High
) then
493 if not Compile_Time_Known_Value
(Aggr_High
(Dim
)) then
494 Aggr_High
(Dim
) := This_High
;
497 Expr_Value
(This_High
) /= Expr_Value
(Aggr_High
(Dim
))
499 Set_Raises_Constraint_Error
(N
);
500 Error_Msg_Warn
:= SPARK_Mode
/= On
;
501 Error_Msg_N
("sub-aggregate high bound mismatch<<", N
);
502 Error_Msg_N
("\Constraint_Error [<<", N
);
507 if Dim
< Aggr_Dimension
then
509 -- Process positional components
511 if Present
(Expressions
(N
)) then
512 Expr
:= First
(Expressions
(N
));
513 while Present
(Expr
) loop
514 Collect_Aggr_Bounds
(Expr
, Dim
+ 1);
519 -- Process component associations
521 if Present
(Component_Associations
(N
)) then
522 Is_Fully_Positional
:= False;
524 Assoc
:= First
(Component_Associations
(N
));
525 while Present
(Assoc
) loop
526 Expr
:= Expression
(Assoc
);
527 Collect_Aggr_Bounds
(Expr
, Dim
+ 1);
532 end Collect_Aggr_Bounds
;
534 -- Array_Aggr_Subtype variables
537 -- The final itype of the overall aggregate
539 Index_Constraints
: constant List_Id
:= New_List
;
540 -- The list of index constraints of the aggregate itype
542 -- Start of processing for Array_Aggr_Subtype
545 -- Make sure that the list of index constraints is properly attached to
546 -- the tree, and then collect the aggregate bounds.
548 Set_Parent
(Index_Constraints
, N
);
549 Collect_Aggr_Bounds
(N
, 1);
551 -- Build the list of constrained indexes of our aggregate itype
553 for J
in 1 .. Aggr_Dimension
loop
554 Create_Index
: declare
555 Index_Base
: constant Entity_Id
:=
556 Base_Type
(Etype
(Aggr_Range
(J
)));
557 Index_Typ
: Entity_Id
;
560 -- Construct the Index subtype, and associate it with the range
561 -- construct that generates it.
564 Create_Itype
(Subtype_Kind
(Ekind
(Index_Base
)), Aggr_Range
(J
));
566 Set_Etype
(Index_Typ
, Index_Base
);
568 if Is_Character_Type
(Index_Base
) then
569 Set_Is_Character_Type
(Index_Typ
);
572 Set_Size_Info
(Index_Typ
, (Index_Base
));
573 Set_RM_Size
(Index_Typ
, RM_Size
(Index_Base
));
574 Set_First_Rep_Item
(Index_Typ
, First_Rep_Item
(Index_Base
));
575 Set_Scalar_Range
(Index_Typ
, Aggr_Range
(J
));
577 if Is_Discrete_Or_Fixed_Point_Type
(Index_Typ
) then
578 Set_RM_Size
(Index_Typ
, UI_From_Int
(Minimum_Size
(Index_Typ
)));
581 Set_Etype
(Aggr_Range
(J
), Index_Typ
);
583 Append
(Aggr_Range
(J
), To
=> Index_Constraints
);
587 -- Now build the Itype
589 Itype
:= Create_Itype
(E_Array_Subtype
, N
);
591 Set_First_Rep_Item
(Itype
, First_Rep_Item
(Typ
));
592 Set_Convention
(Itype
, Convention
(Typ
));
593 Set_Depends_On_Private
(Itype
, Has_Private_Component
(Typ
));
594 Set_Etype
(Itype
, Base_Type
(Typ
));
595 Set_Has_Alignment_Clause
(Itype
, Has_Alignment_Clause
(Typ
));
596 Set_Is_Aliased
(Itype
, Is_Aliased
(Typ
));
597 Set_Depends_On_Private
(Itype
, Depends_On_Private
(Typ
));
599 Copy_Suppress_Status
(Index_Check
, Typ
, Itype
);
600 Copy_Suppress_Status
(Length_Check
, Typ
, Itype
);
602 Set_First_Index
(Itype
, First
(Index_Constraints
));
603 Set_Is_Constrained
(Itype
, True);
604 Set_Is_Internal
(Itype
, True);
606 -- A simple optimization: purely positional aggregates of static
607 -- components should be passed to gigi unexpanded whenever possible, and
608 -- regardless of the staticness of the bounds themselves. Subsequent
609 -- checks in exp_aggr verify that type is not packed, etc.
611 Set_Size_Known_At_Compile_Time
614 and then Comes_From_Source
(N
)
615 and then Size_Known_At_Compile_Time
(Component_Type
(Typ
)));
617 -- We always need a freeze node for a packed array subtype, so that we
618 -- can build the Packed_Array_Impl_Type corresponding to the subtype. If
619 -- expansion is disabled, the packed array subtype is not built, and we
620 -- must not generate a freeze node for the type, or else it will appear
621 -- incomplete to gigi.
624 and then not In_Spec_Expression
625 and then Expander_Active
627 Freeze_Itype
(Itype
, N
);
631 end Array_Aggr_Subtype
;
633 --------------------------------
634 -- Check_Misspelled_Component --
635 --------------------------------
637 procedure Check_Misspelled_Component
638 (Elements
: Elist_Id
;
641 Max_Suggestions
: constant := 2;
643 Nr_Of_Suggestions
: Natural := 0;
644 Suggestion_1
: Entity_Id
:= Empty
;
645 Suggestion_2
: Entity_Id
:= Empty
;
646 Component_Elmt
: Elmt_Id
;
649 -- All the components of List are matched against Component and a count
650 -- is maintained of possible misspellings. When at the end of the
651 -- analysis there are one or two (not more) possible misspellings,
652 -- these misspellings will be suggested as possible corrections.
654 Component_Elmt
:= First_Elmt
(Elements
);
655 while Nr_Of_Suggestions
<= Max_Suggestions
656 and then Present
(Component_Elmt
)
658 if Is_Bad_Spelling_Of
659 (Chars
(Node
(Component_Elmt
)),
662 Nr_Of_Suggestions
:= Nr_Of_Suggestions
+ 1;
664 case Nr_Of_Suggestions
is
665 when 1 => Suggestion_1
:= Node
(Component_Elmt
);
666 when 2 => Suggestion_2
:= Node
(Component_Elmt
);
671 Next_Elmt
(Component_Elmt
);
674 -- Report at most two suggestions
676 if Nr_Of_Suggestions
= 1 then
677 Error_Msg_NE
-- CODEFIX
678 ("\possible misspelling of&", Component
, Suggestion_1
);
680 elsif Nr_Of_Suggestions
= 2 then
681 Error_Msg_Node_2
:= Suggestion_2
;
682 Error_Msg_NE
-- CODEFIX
683 ("\possible misspelling of& or&", Component
, Suggestion_1
);
685 end Check_Misspelled_Component
;
687 ----------------------------------------
688 -- Check_Expr_OK_In_Limited_Aggregate --
689 ----------------------------------------
691 procedure Check_Expr_OK_In_Limited_Aggregate
(Expr
: Node_Id
) is
693 if Is_Limited_Type
(Etype
(Expr
))
694 and then Comes_From_Source
(Expr
)
696 if In_Instance_Body
or else In_Inlined_Body
then
699 elsif not OK_For_Limited_Init
(Etype
(Expr
), Expr
) then
701 ("initialization not allowed for limited types", Expr
);
702 Explain_Limited_Type
(Etype
(Expr
), Expr
);
705 end Check_Expr_OK_In_Limited_Aggregate
;
707 -------------------------------
708 -- Check_Qualified_Aggregate --
709 -------------------------------
711 procedure Check_Qualified_Aggregate
(Level
: Nat
; Expr
: Node_Id
) is
717 if Nkind
(Parent
(Expr
)) /= N_Qualified_Expression
then
718 Check_SPARK_05_Restriction
("aggregate should be qualified", Expr
);
722 Comp_Expr
:= First
(Expressions
(Expr
));
723 while Present
(Comp_Expr
) loop
724 if Nkind
(Comp_Expr
) = N_Aggregate
then
725 Check_Qualified_Aggregate
(Level
- 1, Comp_Expr
);
728 Comp_Expr
:= Next
(Comp_Expr
);
731 Comp_Assn
:= First
(Component_Associations
(Expr
));
732 while Present
(Comp_Assn
) loop
733 Comp_Expr
:= Expression
(Comp_Assn
);
735 if Nkind
(Comp_Expr
) = N_Aggregate
then
736 Check_Qualified_Aggregate
(Level
- 1, Comp_Expr
);
739 Comp_Assn
:= Next
(Comp_Assn
);
742 end Check_Qualified_Aggregate
;
744 ----------------------------------------
745 -- Check_Static_Discriminated_Subtype --
746 ----------------------------------------
748 procedure Check_Static_Discriminated_Subtype
(T
: Entity_Id
; V
: Node_Id
) is
749 Disc
: constant Entity_Id
:= First_Discriminant
(T
);
754 if Has_Record_Rep_Clause
(T
) then
757 elsif Present
(Next_Discriminant
(Disc
)) then
760 elsif Nkind
(V
) /= N_Integer_Literal
then
764 Comp
:= First_Component
(T
);
765 while Present
(Comp
) loop
766 if Is_Scalar_Type
(Etype
(Comp
)) then
769 elsif Is_Private_Type
(Etype
(Comp
))
770 and then Present
(Full_View
(Etype
(Comp
)))
771 and then Is_Scalar_Type
(Full_View
(Etype
(Comp
)))
775 elsif Is_Array_Type
(Etype
(Comp
)) then
776 if Is_Bit_Packed_Array
(Etype
(Comp
)) then
780 Ind
:= First_Index
(Etype
(Comp
));
781 while Present
(Ind
) loop
782 if Nkind
(Ind
) /= N_Range
783 or else Nkind
(Low_Bound
(Ind
)) /= N_Integer_Literal
784 or else Nkind
(High_Bound
(Ind
)) /= N_Integer_Literal
796 Next_Component
(Comp
);
799 -- On exit, all components have statically known sizes
801 Set_Size_Known_At_Compile_Time
(T
);
802 end Check_Static_Discriminated_Subtype
;
804 -------------------------
805 -- Is_Others_Aggregate --
806 -------------------------
808 function Is_Others_Aggregate
(Aggr
: Node_Id
) return Boolean is
810 return No
(Expressions
(Aggr
))
812 Nkind
(First
(Choice_List
(First
(Component_Associations
(Aggr
))))) =
814 end Is_Others_Aggregate
;
816 ----------------------------
817 -- Is_Top_Level_Aggregate --
818 ----------------------------
820 function Is_Top_Level_Aggregate
(Expr
: Node_Id
) return Boolean is
822 return Nkind
(Parent
(Expr
)) /= N_Aggregate
823 and then (Nkind
(Parent
(Expr
)) /= N_Component_Association
824 or else Nkind
(Parent
(Parent
(Expr
))) /= N_Aggregate
);
825 end Is_Top_Level_Aggregate
;
827 --------------------------------
828 -- Make_String_Into_Aggregate --
829 --------------------------------
831 procedure Make_String_Into_Aggregate
(N
: Node_Id
) is
832 Exprs
: constant List_Id
:= New_List
;
833 Loc
: constant Source_Ptr
:= Sloc
(N
);
834 Str
: constant String_Id
:= Strval
(N
);
835 Strlen
: constant Nat
:= String_Length
(Str
);
843 for J
in 1 .. Strlen
loop
844 C
:= Get_String_Char
(Str
, J
);
845 Set_Character_Literal_Name
(C
);
848 Make_Character_Literal
(P
,
850 Char_Literal_Value
=> UI_From_CC
(C
));
851 Set_Etype
(C_Node
, Any_Character
);
852 Append_To
(Exprs
, C_Node
);
855 -- Something special for wide strings???
858 New_N
:= Make_Aggregate
(Loc
, Expressions
=> Exprs
);
859 Set_Analyzed
(New_N
);
860 Set_Etype
(New_N
, Any_Composite
);
863 end Make_String_Into_Aggregate
;
865 -----------------------
866 -- Resolve_Aggregate --
867 -----------------------
869 procedure Resolve_Aggregate
(N
: Node_Id
; Typ
: Entity_Id
) is
870 Loc
: constant Source_Ptr
:= Sloc
(N
);
871 Pkind
: constant Node_Kind
:= Nkind
(Parent
(N
));
873 Aggr_Subtyp
: Entity_Id
;
874 -- The actual aggregate subtype. This is not necessarily the same as Typ
875 -- which is the subtype of the context in which the aggregate was found.
878 -- Ignore junk empty aggregate resulting from parser error
880 if No
(Expressions
(N
))
881 and then No
(Component_Associations
(N
))
882 and then not Null_Record_Present
(N
)
887 -- If the aggregate has box-initialized components, its type must be
888 -- frozen so that initialization procedures can properly be called
889 -- in the resolution that follows. The replacement of boxes with
890 -- initialization calls is properly an expansion activity but it must
891 -- be done during resolution.
894 and then Present
(Component_Associations
(N
))
900 Comp
:= First
(Component_Associations
(N
));
901 while Present
(Comp
) loop
902 if Box_Present
(Comp
) then
903 Insert_Actions
(N
, Freeze_Entity
(Typ
, N
));
912 -- An unqualified aggregate is restricted in SPARK to:
914 -- An aggregate item inside an aggregate for a multi-dimensional array
916 -- An expression being assigned to an unconstrained array, but only if
917 -- the aggregate specifies a value for OTHERS only.
919 if Nkind
(Parent
(N
)) = N_Qualified_Expression
then
920 if Is_Array_Type
(Typ
) then
921 Check_Qualified_Aggregate
(Number_Dimensions
(Typ
), N
);
923 Check_Qualified_Aggregate
(1, N
);
926 if Is_Array_Type
(Typ
)
927 and then Nkind
(Parent
(N
)) = N_Assignment_Statement
928 and then not Is_Constrained
(Etype
(Name
(Parent
(N
))))
930 if not Is_Others_Aggregate
(N
) then
931 Check_SPARK_05_Restriction
932 ("array aggregate should have only OTHERS", N
);
935 elsif Is_Top_Level_Aggregate
(N
) then
936 Check_SPARK_05_Restriction
("aggregate should be qualified", N
);
938 -- The legality of this unqualified aggregate is checked by calling
939 -- Check_Qualified_Aggregate from one of its enclosing aggregate,
940 -- unless one of these already causes an error to be issued.
947 -- Check for aggregates not allowed in configurable run-time mode.
948 -- We allow all cases of aggregates that do not come from source, since
949 -- these are all assumed to be small (e.g. bounds of a string literal).
950 -- We also allow aggregates of types we know to be small.
952 if not Support_Aggregates_On_Target
953 and then Comes_From_Source
(N
)
954 and then (not Known_Static_Esize
(Typ
) or else Esize
(Typ
) > 64)
956 Error_Msg_CRT
("aggregate", N
);
959 -- Ada 2005 (AI-287): Limited aggregates allowed
961 -- In an instance, ignore aggregate subcomponents tnat may be limited,
962 -- because they originate in view conflicts. If the original aggregate
963 -- is legal and the actuals are legal, the aggregate itself is legal.
965 if Is_Limited_Type
(Typ
)
966 and then Ada_Version
< Ada_2005
967 and then not In_Instance
969 Error_Msg_N
("aggregate type cannot be limited", N
);
970 Explain_Limited_Type
(Typ
, N
);
972 elsif Is_Class_Wide_Type
(Typ
) then
973 Error_Msg_N
("type of aggregate cannot be class-wide", N
);
975 elsif Typ
= Any_String
976 or else Typ
= Any_Composite
978 Error_Msg_N
("no unique type for aggregate", N
);
979 Set_Etype
(N
, Any_Composite
);
981 elsif Is_Array_Type
(Typ
) and then Null_Record_Present
(N
) then
982 Error_Msg_N
("null record forbidden in array aggregate", N
);
984 elsif Is_Record_Type
(Typ
) then
985 Resolve_Record_Aggregate
(N
, Typ
);
987 elsif Is_Array_Type
(Typ
) then
989 -- First a special test, for the case of a positional aggregate of
990 -- characters which can be replaced by a string literal.
992 -- Do not perform this transformation if this was a string literal
993 -- to start with, whose components needed constraint checks, or if
994 -- the component type is non-static, because it will require those
995 -- checks and be transformed back into an aggregate. If the index
996 -- type is not Integer the aggregate may represent a user-defined
997 -- string type but the context might need the original type so we
998 -- do not perform the transformation at this point.
1000 if Number_Dimensions
(Typ
) = 1
1001 and then Is_Standard_Character_Type
(Component_Type
(Typ
))
1002 and then No
(Component_Associations
(N
))
1003 and then not Is_Limited_Composite
(Typ
)
1004 and then not Is_Private_Composite
(Typ
)
1005 and then not Is_Bit_Packed_Array
(Typ
)
1006 and then Nkind
(Original_Node
(Parent
(N
))) /= N_String_Literal
1007 and then Is_OK_Static_Subtype
(Component_Type
(Typ
))
1008 and then Base_Type
(Etype
(First_Index
(Typ
))) =
1009 Base_Type
(Standard_Integer
)
1015 Expr
:= First
(Expressions
(N
));
1016 while Present
(Expr
) loop
1017 exit when Nkind
(Expr
) /= N_Character_Literal
;
1024 Expr
:= First
(Expressions
(N
));
1025 while Present
(Expr
) loop
1026 Store_String_Char
(UI_To_CC
(Char_Literal_Value
(Expr
)));
1030 Rewrite
(N
, Make_String_Literal
(Loc
, End_String
));
1032 Analyze_And_Resolve
(N
, Typ
);
1038 -- Here if we have a real aggregate to deal with
1040 Array_Aggregate
: declare
1041 Aggr_Resolved
: Boolean;
1043 Aggr_Typ
: constant Entity_Id
:= Etype
(Typ
);
1044 -- This is the unconstrained array type, which is the type against
1045 -- which the aggregate is to be resolved. Typ itself is the array
1046 -- type of the context which may not be the same subtype as the
1047 -- subtype for the final aggregate.
1050 -- In the following we determine whether an OTHERS choice is
1051 -- allowed inside the array aggregate. The test checks the context
1052 -- in which the array aggregate occurs. If the context does not
1053 -- permit it, or the aggregate type is unconstrained, an OTHERS
1054 -- choice is not allowed (except that it is always allowed on the
1055 -- right-hand side of an assignment statement; in this case the
1056 -- constrainedness of the type doesn't matter).
1058 -- If expansion is disabled (generic context, or semantics-only
1059 -- mode) actual subtypes cannot be constructed, and the type of an
1060 -- object may be its unconstrained nominal type. However, if the
1061 -- context is an assignment, we assume that OTHERS is allowed,
1062 -- because the target of the assignment will have a constrained
1063 -- subtype when fully compiled.
1065 -- Note that there is no node for Explicit_Actual_Parameter.
1066 -- To test for this context we therefore have to test for node
1067 -- N_Parameter_Association which itself appears only if there is a
1068 -- formal parameter. Consequently we also need to test for
1069 -- N_Procedure_Call_Statement or N_Function_Call.
1071 -- The context may be an N_Reference node, created by expansion.
1072 -- Legality of the others clause was established in the source,
1073 -- so the context is legal.
1075 Set_Etype
(N
, Aggr_Typ
); -- May be overridden later on
1077 if Pkind
= N_Assignment_Statement
1078 or else (Is_Constrained
(Typ
)
1080 (Pkind
= N_Parameter_Association
or else
1081 Pkind
= N_Function_Call
or else
1082 Pkind
= N_Procedure_Call_Statement
or else
1083 Pkind
= N_Generic_Association
or else
1084 Pkind
= N_Formal_Object_Declaration
or else
1085 Pkind
= N_Simple_Return_Statement
or else
1086 Pkind
= N_Object_Declaration
or else
1087 Pkind
= N_Component_Declaration
or else
1088 Pkind
= N_Parameter_Specification
or else
1089 Pkind
= N_Qualified_Expression
or else
1090 Pkind
= N_Reference
or else
1091 Pkind
= N_Aggregate
or else
1092 Pkind
= N_Extension_Aggregate
or else
1093 Pkind
= N_Component_Association
))
1096 Resolve_Array_Aggregate
1098 Index
=> First_Index
(Aggr_Typ
),
1099 Index_Constr
=> First_Index
(Typ
),
1100 Component_Typ
=> Component_Type
(Typ
),
1101 Others_Allowed
=> True);
1104 Resolve_Array_Aggregate
1106 Index
=> First_Index
(Aggr_Typ
),
1107 Index_Constr
=> First_Index
(Aggr_Typ
),
1108 Component_Typ
=> Component_Type
(Typ
),
1109 Others_Allowed
=> False);
1112 if not Aggr_Resolved
then
1114 -- A parenthesized expression may have been intended as an
1115 -- aggregate, leading to a type error when analyzing the
1116 -- component. This can also happen for a nested component
1117 -- (see Analyze_Aggr_Expr).
1119 if Paren_Count
(N
) > 0 then
1121 ("positional aggregate cannot have one component", N
);
1124 Aggr_Subtyp
:= Any_Composite
;
1127 Aggr_Subtyp
:= Array_Aggr_Subtype
(N
, Typ
);
1130 Set_Etype
(N
, Aggr_Subtyp
);
1131 end Array_Aggregate
;
1133 elsif Is_Private_Type
(Typ
)
1134 and then Present
(Full_View
(Typ
))
1135 and then (In_Inlined_Body
or In_Instance_Body
)
1136 and then Is_Composite_Type
(Full_View
(Typ
))
1138 Resolve
(N
, Full_View
(Typ
));
1141 Error_Msg_N
("illegal context for aggregate", N
);
1144 -- If we can determine statically that the evaluation of the aggregate
1145 -- raises Constraint_Error, then replace the aggregate with an
1146 -- N_Raise_Constraint_Error node, but set the Etype to the right
1147 -- aggregate subtype. Gigi needs this.
1149 if Raises_Constraint_Error
(N
) then
1150 Aggr_Subtyp
:= Etype
(N
);
1152 Make_Raise_Constraint_Error
(Loc
, Reason
=> CE_Range_Check_Failed
));
1153 Set_Raises_Constraint_Error
(N
);
1154 Set_Etype
(N
, Aggr_Subtyp
);
1158 Check_Function_Writable_Actuals
(N
);
1159 end Resolve_Aggregate
;
1161 -----------------------------
1162 -- Resolve_Array_Aggregate --
1163 -----------------------------
1165 function Resolve_Array_Aggregate
1168 Index_Constr
: Node_Id
;
1169 Component_Typ
: Entity_Id
;
1170 Others_Allowed
: Boolean) return Boolean
1172 Loc
: constant Source_Ptr
:= Sloc
(N
);
1174 Failure
: constant Boolean := False;
1175 Success
: constant Boolean := True;
1177 Index_Typ
: constant Entity_Id
:= Etype
(Index
);
1178 Index_Typ_Low
: constant Node_Id
:= Type_Low_Bound
(Index_Typ
);
1179 Index_Typ_High
: constant Node_Id
:= Type_High_Bound
(Index_Typ
);
1180 -- The type of the index corresponding to the array sub-aggregate along
1181 -- with its low and upper bounds.
1183 Index_Base
: constant Entity_Id
:= Base_Type
(Index_Typ
);
1184 Index_Base_Low
: constant Node_Id
:= Type_Low_Bound
(Index_Base
);
1185 Index_Base_High
: constant Node_Id
:= Type_High_Bound
(Index_Base
);
1186 -- Ditto for the base type
1188 Others_Present
: Boolean := False;
1190 Nb_Choices
: Nat
:= 0;
1191 -- Contains the overall number of named choices in this sub-aggregate
1193 function Add
(Val
: Uint
; To
: Node_Id
) return Node_Id
;
1194 -- Creates a new expression node where Val is added to expression To.
1195 -- Tries to constant fold whenever possible. To must be an already
1196 -- analyzed expression.
1198 procedure Check_Bound
(BH
: Node_Id
; AH
: in out Node_Id
);
1199 -- Checks that AH (the upper bound of an array aggregate) is less than
1200 -- or equal to BH (the upper bound of the index base type). If the check
1201 -- fails, a warning is emitted, the Raises_Constraint_Error flag of N is
1202 -- set, and AH is replaced with a duplicate of BH.
1204 procedure Check_Bounds
(L
, H
: Node_Id
; AL
, AH
: Node_Id
);
1205 -- Checks that range AL .. AH is compatible with range L .. H. Emits a
1206 -- warning if not and sets the Raises_Constraint_Error flag in N.
1208 procedure Check_Length
(L
, H
: Node_Id
; Len
: Uint
);
1209 -- Checks that range L .. H contains at least Len elements. Emits a
1210 -- warning if not and sets the Raises_Constraint_Error flag in N.
1212 function Dynamic_Or_Null_Range
(L
, H
: Node_Id
) return Boolean;
1213 -- Returns True if range L .. H is dynamic or null
1215 procedure Get
(Value
: out Uint
; From
: Node_Id
; OK
: out Boolean);
1216 -- Given expression node From, this routine sets OK to False if it
1217 -- cannot statically evaluate From. Otherwise it stores this static
1218 -- value into Value.
1220 function Resolve_Aggr_Expr
1222 Single_Elmt
: Boolean) return Boolean;
1223 -- Resolves aggregate expression Expr. Returns False if resolution
1224 -- fails. If Single_Elmt is set to False, the expression Expr may be
1225 -- used to initialize several array aggregate elements (this can happen
1226 -- for discrete choices such as "L .. H => Expr" or the OTHERS choice).
1227 -- In this event we do not resolve Expr unless expansion is disabled.
1228 -- To know why, see the DELAYED COMPONENT RESOLUTION note above.
1230 -- NOTE: In the case of "... => <>", we pass the in the
1231 -- N_Component_Association node as Expr, since there is no Expression in
1232 -- that case, and we need a Sloc for the error message.
1234 procedure Resolve_Iterated_Component_Association
1236 Index_Typ
: Entity_Id
);
1243 function Add
(Val
: Uint
; To
: Node_Id
) return Node_Id
is
1249 if Raises_Constraint_Error
(To
) then
1253 -- First test if we can do constant folding
1255 if Compile_Time_Known_Value
(To
)
1256 or else Nkind
(To
) = N_Integer_Literal
1258 Expr_Pos
:= Make_Integer_Literal
(Loc
, Expr_Value
(To
) + Val
);
1259 Set_Is_Static_Expression
(Expr_Pos
);
1260 Set_Etype
(Expr_Pos
, Etype
(To
));
1261 Set_Analyzed
(Expr_Pos
, Analyzed
(To
));
1263 if not Is_Enumeration_Type
(Index_Typ
) then
1266 -- If we are dealing with enumeration return
1267 -- Index_Typ'Val (Expr_Pos)
1271 Make_Attribute_Reference
1273 Prefix
=> New_Occurrence_Of
(Index_Typ
, Loc
),
1274 Attribute_Name
=> Name_Val
,
1275 Expressions
=> New_List
(Expr_Pos
));
1281 -- If we are here no constant folding possible
1283 if not Is_Enumeration_Type
(Index_Base
) then
1286 Left_Opnd
=> Duplicate_Subexpr
(To
),
1287 Right_Opnd
=> Make_Integer_Literal
(Loc
, Val
));
1289 -- If we are dealing with enumeration return
1290 -- Index_Typ'Val (Index_Typ'Pos (To) + Val)
1294 Make_Attribute_Reference
1296 Prefix
=> New_Occurrence_Of
(Index_Typ
, Loc
),
1297 Attribute_Name
=> Name_Pos
,
1298 Expressions
=> New_List
(Duplicate_Subexpr
(To
)));
1302 Left_Opnd
=> To_Pos
,
1303 Right_Opnd
=> Make_Integer_Literal
(Loc
, Val
));
1306 Make_Attribute_Reference
1308 Prefix
=> New_Occurrence_Of
(Index_Typ
, Loc
),
1309 Attribute_Name
=> Name_Val
,
1310 Expressions
=> New_List
(Expr_Pos
));
1312 -- If the index type has a non standard representation, the
1313 -- attributes 'Val and 'Pos expand into function calls and the
1314 -- resulting expression is considered non-safe for reevaluation
1315 -- by the backend. Relocate it into a constant temporary in order
1316 -- to make it safe for reevaluation.
1318 if Has_Non_Standard_Rep
(Etype
(N
)) then
1323 Def_Id
:= Make_Temporary
(Loc
, 'R', Expr
);
1324 Set_Etype
(Def_Id
, Index_Typ
);
1326 Make_Object_Declaration
(Loc
,
1327 Defining_Identifier
=> Def_Id
,
1328 Object_Definition
=>
1329 New_Occurrence_Of
(Index_Typ
, Loc
),
1330 Constant_Present
=> True,
1331 Expression
=> Relocate_Node
(Expr
)));
1333 Expr
:= New_Occurrence_Of
(Def_Id
, Loc
);
1345 procedure Check_Bound
(BH
: Node_Id
; AH
: in out Node_Id
) is
1353 Get
(Value
=> Val_BH
, From
=> BH
, OK
=> OK_BH
);
1354 Get
(Value
=> Val_AH
, From
=> AH
, OK
=> OK_AH
);
1356 if OK_BH
and then OK_AH
and then Val_BH
< Val_AH
then
1357 Set_Raises_Constraint_Error
(N
);
1358 Error_Msg_Warn
:= SPARK_Mode
/= On
;
1359 Error_Msg_N
("upper bound out of range<<", AH
);
1360 Error_Msg_N
("\Constraint_Error [<<", AH
);
1362 -- You need to set AH to BH or else in the case of enumerations
1363 -- indexes we will not be able to resolve the aggregate bounds.
1365 AH
:= Duplicate_Subexpr
(BH
);
1373 procedure Check_Bounds
(L
, H
: Node_Id
; AL
, AH
: Node_Id
) is
1384 pragma Warnings
(Off
, OK_AL
);
1385 pragma Warnings
(Off
, OK_AH
);
1388 if Raises_Constraint_Error
(N
)
1389 or else Dynamic_Or_Null_Range
(AL
, AH
)
1394 Get
(Value
=> Val_L
, From
=> L
, OK
=> OK_L
);
1395 Get
(Value
=> Val_H
, From
=> H
, OK
=> OK_H
);
1397 Get
(Value
=> Val_AL
, From
=> AL
, OK
=> OK_AL
);
1398 Get
(Value
=> Val_AH
, From
=> AH
, OK
=> OK_AH
);
1400 if OK_L
and then Val_L
> Val_AL
then
1401 Set_Raises_Constraint_Error
(N
);
1402 Error_Msg_Warn
:= SPARK_Mode
/= On
;
1403 Error_Msg_N
("lower bound of aggregate out of range<<", N
);
1404 Error_Msg_N
("\Constraint_Error [<<", N
);
1407 if OK_H
and then Val_H
< Val_AH
then
1408 Set_Raises_Constraint_Error
(N
);
1409 Error_Msg_Warn
:= SPARK_Mode
/= On
;
1410 Error_Msg_N
("upper bound of aggregate out of range<<", N
);
1411 Error_Msg_N
("\Constraint_Error [<<", N
);
1419 procedure Check_Length
(L
, H
: Node_Id
; Len
: Uint
) is
1429 if Raises_Constraint_Error
(N
) then
1433 Get
(Value
=> Val_L
, From
=> L
, OK
=> OK_L
);
1434 Get
(Value
=> Val_H
, From
=> H
, OK
=> OK_H
);
1436 if not OK_L
or else not OK_H
then
1440 -- If null range length is zero
1442 if Val_L
> Val_H
then
1443 Range_Len
:= Uint_0
;
1445 Range_Len
:= Val_H
- Val_L
+ 1;
1448 if Range_Len
< Len
then
1449 Set_Raises_Constraint_Error
(N
);
1450 Error_Msg_Warn
:= SPARK_Mode
/= On
;
1451 Error_Msg_N
("too many elements<<", N
);
1452 Error_Msg_N
("\Constraint_Error [<<", N
);
1456 ---------------------------
1457 -- Dynamic_Or_Null_Range --
1458 ---------------------------
1460 function Dynamic_Or_Null_Range
(L
, H
: Node_Id
) return Boolean is
1468 Get
(Value
=> Val_L
, From
=> L
, OK
=> OK_L
);
1469 Get
(Value
=> Val_H
, From
=> H
, OK
=> OK_H
);
1471 return not OK_L
or else not OK_H
1472 or else not Is_OK_Static_Expression
(L
)
1473 or else not Is_OK_Static_Expression
(H
)
1474 or else Val_L
> Val_H
;
1475 end Dynamic_Or_Null_Range
;
1481 procedure Get
(Value
: out Uint
; From
: Node_Id
; OK
: out Boolean) is
1485 if Compile_Time_Known_Value
(From
) then
1486 Value
:= Expr_Value
(From
);
1488 -- If expression From is something like Some_Type'Val (10) then
1491 elsif Nkind
(From
) = N_Attribute_Reference
1492 and then Attribute_Name
(From
) = Name_Val
1493 and then Compile_Time_Known_Value
(First
(Expressions
(From
)))
1495 Value
:= Expr_Value
(First
(Expressions
(From
)));
1502 -----------------------
1503 -- Resolve_Aggr_Expr --
1504 -----------------------
1506 function Resolve_Aggr_Expr
1508 Single_Elmt
: Boolean) return Boolean
1510 Nxt_Ind
: constant Node_Id
:= Next_Index
(Index
);
1511 Nxt_Ind_Constr
: constant Node_Id
:= Next_Index
(Index_Constr
);
1512 -- Index is the current index corresponding to the expression
1514 Resolution_OK
: Boolean := True;
1515 -- Set to False if resolution of the expression failed
1518 -- Defend against previous errors
1520 if Nkind
(Expr
) = N_Error
1521 or else Error_Posted
(Expr
)
1526 -- If the array type against which we are resolving the aggregate
1527 -- has several dimensions, the expressions nested inside the
1528 -- aggregate must be further aggregates (or strings).
1530 if Present
(Nxt_Ind
) then
1531 if Nkind
(Expr
) /= N_Aggregate
then
1533 -- A string literal can appear where a one-dimensional array
1534 -- of characters is expected. If the literal looks like an
1535 -- operator, it is still an operator symbol, which will be
1536 -- transformed into a string when analyzed.
1538 if Is_Character_Type
(Component_Typ
)
1539 and then No
(Next_Index
(Nxt_Ind
))
1540 and then Nkind_In
(Expr
, N_String_Literal
, N_Operator_Symbol
)
1542 -- A string literal used in a multidimensional array
1543 -- aggregate in place of the final one-dimensional
1544 -- aggregate must not be enclosed in parentheses.
1546 if Paren_Count
(Expr
) /= 0 then
1547 Error_Msg_N
("no parenthesis allowed here", Expr
);
1550 Make_String_Into_Aggregate
(Expr
);
1553 Error_Msg_N
("nested array aggregate expected", Expr
);
1555 -- If the expression is parenthesized, this may be
1556 -- a missing component association for a 1-aggregate.
1558 if Paren_Count
(Expr
) > 0 then
1560 ("\if single-component aggregate is intended, "
1561 & "write e.g. (1 ='> ...)", Expr
);
1568 -- If it's "... => <>", nothing to resolve
1570 if Nkind
(Expr
) = N_Component_Association
then
1571 pragma Assert
(Box_Present
(Expr
));
1575 -- Ada 2005 (AI-231): Propagate the type to the nested aggregate.
1576 -- Required to check the null-exclusion attribute (if present).
1577 -- This value may be overridden later on.
1579 Set_Etype
(Expr
, Etype
(N
));
1581 Resolution_OK
:= Resolve_Array_Aggregate
1582 (Expr
, Nxt_Ind
, Nxt_Ind_Constr
, Component_Typ
, Others_Allowed
);
1585 -- If it's "... => <>", nothing to resolve
1587 if Nkind
(Expr
) = N_Component_Association
then
1588 pragma Assert
(Box_Present
(Expr
));
1592 -- Do not resolve the expressions of discrete or others choices
1593 -- unless the expression covers a single component, or the
1594 -- expander is inactive.
1596 -- In SPARK mode, expressions that can perform side-effects will
1597 -- be recognized by the gnat2why back-end, and the whole
1598 -- subprogram will be ignored. So semantic analysis can be
1599 -- performed safely.
1602 or else not Expander_Active
1603 or else In_Spec_Expression
1605 Analyze_And_Resolve
(Expr
, Component_Typ
);
1606 Check_Expr_OK_In_Limited_Aggregate
(Expr
);
1607 Check_Non_Static_Context
(Expr
);
1608 Aggregate_Constraint_Checks
(Expr
, Component_Typ
);
1609 Check_Unset_Reference
(Expr
);
1613 -- If an aggregate component has a type with predicates, an explicit
1614 -- predicate check must be applied, as for an assignment statement,
1615 -- because the aggegate might not be expanded into individual
1616 -- component assignments. If the expression covers several components
1617 -- the analysis and the predicate check take place later.
1619 if Present
(Predicate_Function
(Component_Typ
))
1620 and then Analyzed
(Expr
)
1622 Apply_Predicate_Check
(Expr
, Component_Typ
);
1625 if Raises_Constraint_Error
(Expr
)
1626 and then Nkind
(Parent
(Expr
)) /= N_Component_Association
1628 Set_Raises_Constraint_Error
(N
);
1631 -- If the expression has been marked as requiring a range check,
1632 -- then generate it here. It's a bit odd to be generating such
1633 -- checks in the analyzer, but harmless since Generate_Range_Check
1634 -- does nothing (other than making sure Do_Range_Check is set) if
1635 -- the expander is not active.
1637 if Do_Range_Check
(Expr
) then
1638 Generate_Range_Check
(Expr
, Component_Typ
, CE_Range_Check_Failed
);
1641 return Resolution_OK
;
1642 end Resolve_Aggr_Expr
;
1644 --------------------------------------------
1645 -- Resolve_Iterated_Component_Association --
1646 --------------------------------------------
1648 procedure Resolve_Iterated_Component_Association
1650 Index_Typ
: Entity_Id
)
1652 Id
: constant Entity_Id
:= Defining_Identifier
(N
);
1653 Loc
: constant Source_Ptr
:= Sloc
(N
);
1660 Choice
:= First
(Discrete_Choices
(N
));
1662 while Present
(Choice
) loop
1663 if Nkind
(Choice
) = N_Others_Choice
then
1664 Others_Present
:= True;
1669 -- Choice can be a subtype name, a range, or an expression
1671 if Is_Entity_Name
(Choice
)
1672 and then Is_Type
(Entity
(Choice
))
1673 and then Base_Type
(Entity
(Choice
)) = Base_Type
(Index_Typ
)
1678 Analyze_And_Resolve
(Choice
, Index_Typ
);
1685 -- Create a scope in which to introduce an index, which is usually
1686 -- visible in the expression for the component, and needed for its
1689 Ent
:= New_Internal_Entity
(E_Loop
, Current_Scope
, Loc
, 'L');
1690 Set_Etype
(Ent
, Standard_Void_Type
);
1691 Set_Parent
(Ent
, Parent
(N
));
1693 -- Decorate the index variable in the current scope. The association
1694 -- may have several choices, each one leading to a loop, so we create
1695 -- this variable only once to prevent homonyms in this scope.
1696 -- The expression has to be analyzed once the index variable is
1697 -- directly visible. Mark the variable as referenced to prevent
1698 -- spurious warnings, given that subsequent uses of its name in the
1699 -- expression will reference the internal (synonym) loop variable.
1701 if No
(Scope
(Id
)) then
1703 Set_Etype
(Id
, Index_Typ
);
1704 Set_Ekind
(Id
, E_Variable
);
1705 Set_Scope
(Id
, Ent
);
1706 Set_Referenced
(Id
);
1710 Dummy
:= Resolve_Aggr_Expr
(Expression
(N
), False);
1712 end Resolve_Iterated_Component_Association
;
1721 Aggr_Low
: Node_Id
:= Empty
;
1722 Aggr_High
: Node_Id
:= Empty
;
1723 -- The actual low and high bounds of this sub-aggregate
1725 Case_Table_Size
: Nat
;
1726 -- Contains the size of the case table needed to sort aggregate choices
1728 Choices_Low
: Node_Id
:= Empty
;
1729 Choices_High
: Node_Id
:= Empty
;
1730 -- The lowest and highest discrete choices values for a named aggregate
1732 Delete_Choice
: Boolean;
1733 -- Used when replacing a subtype choice with predicate by a list
1735 Nb_Elements
: Uint
:= Uint_0
;
1736 -- The number of elements in a positional aggregate
1738 Nb_Discrete_Choices
: Nat
:= 0;
1739 -- The overall number of discrete choices (not counting others choice)
1741 -- Start of processing for Resolve_Array_Aggregate
1744 -- Ignore junk empty aggregate resulting from parser error
1746 if No
(Expressions
(N
))
1747 and then No
(Component_Associations
(N
))
1748 and then not Null_Record_Present
(N
)
1753 -- STEP 1: make sure the aggregate is correctly formatted
1755 if Present
(Component_Associations
(N
)) then
1756 Assoc
:= First
(Component_Associations
(N
));
1757 while Present
(Assoc
) loop
1758 if Nkind
(Assoc
) = N_Iterated_Component_Association
then
1759 Resolve_Iterated_Component_Association
(Assoc
, Index_Typ
);
1762 Choice
:= First
(Choice_List
(Assoc
));
1763 Delete_Choice
:= False;
1764 while Present
(Choice
) loop
1765 if Nkind
(Choice
) = N_Others_Choice
then
1766 Others_Present
:= True;
1768 if Choice
/= First
(Choice_List
(Assoc
))
1769 or else Present
(Next
(Choice
))
1772 ("OTHERS must appear alone in a choice list", Choice
);
1776 if Present
(Next
(Assoc
)) then
1778 ("OTHERS must appear last in an aggregate", Choice
);
1782 if Ada_Version
= Ada_83
1783 and then Assoc
/= First
(Component_Associations
(N
))
1784 and then Nkind_In
(Parent
(N
), N_Assignment_Statement
,
1785 N_Object_Declaration
)
1788 ("(Ada 83) illegal context for OTHERS choice", N
);
1791 elsif Is_Entity_Name
(Choice
) then
1795 E
: constant Entity_Id
:= Entity
(Choice
);
1801 if Is_Type
(E
) and then Has_Predicates
(E
) then
1802 Freeze_Before
(N
, E
);
1804 if Has_Dynamic_Predicate_Aspect
(E
) then
1806 ("subtype& has dynamic predicate, not allowed "
1807 & "in aggregate choice", Choice
, E
);
1809 elsif not Is_OK_Static_Subtype
(E
) then
1811 ("non-static subtype& has predicate, not allowed "
1812 & "in aggregate choice", Choice
, E
);
1815 -- If the subtype has a static predicate, replace the
1816 -- original choice with the list of individual values
1817 -- covered by the predicate. Do not perform this
1818 -- transformation if we need to preserve the source
1820 -- This should be deferred to expansion time ???
1822 if Present
(Static_Discrete_Predicate
(E
))
1823 and then not ASIS_Mode
1825 Delete_Choice
:= True;
1828 P
:= First
(Static_Discrete_Predicate
(E
));
1829 while Present
(P
) loop
1831 Set_Sloc
(C
, Sloc
(Choice
));
1832 Append_To
(New_Cs
, C
);
1836 Insert_List_After
(Choice
, New_Cs
);
1842 Nb_Choices
:= Nb_Choices
+ 1;
1845 C
: constant Node_Id
:= Choice
;
1850 if Delete_Choice
then
1852 Nb_Choices
:= Nb_Choices
- 1;
1853 Delete_Choice
:= False;
1862 -- At this point we know that the others choice, if present, is by
1863 -- itself and appears last in the aggregate. Check if we have mixed
1864 -- positional and discrete associations (other than the others choice).
1866 if Present
(Expressions
(N
))
1867 and then (Nb_Choices
> 1
1868 or else (Nb_Choices
= 1 and then not Others_Present
))
1871 ("named association cannot follow positional association",
1872 First
(Choice_List
(First
(Component_Associations
(N
)))));
1876 -- Test for the validity of an others choice if present
1878 if Others_Present
and then not Others_Allowed
then
1880 ("OTHERS choice not allowed here",
1881 First
(Choices
(First
(Component_Associations
(N
)))));
1885 -- Protect against cascaded errors
1887 if Etype
(Index_Typ
) = Any_Type
then
1891 -- STEP 2: Process named components
1893 if No
(Expressions
(N
)) then
1894 if Others_Present
then
1895 Case_Table_Size
:= Nb_Choices
- 1;
1897 Case_Table_Size
:= Nb_Choices
;
1901 function Empty_Range
(A
: Node_Id
) return Boolean;
1902 -- If an association covers an empty range, some warnings on the
1903 -- expression of the association can be disabled.
1909 function Empty_Range
(A
: Node_Id
) return Boolean is
1910 R
: constant Node_Id
:= First
(Choices
(A
));
1912 return No
(Next
(R
))
1913 and then Nkind
(R
) = N_Range
1914 and then Compile_Time_Compare
1915 (Low_Bound
(R
), High_Bound
(R
), False) = GT
;
1922 -- Denote the lowest and highest values in an aggregate choice
1924 S_Low
: Node_Id
:= Empty
;
1925 S_High
: Node_Id
:= Empty
;
1926 -- if a choice in an aggregate is a subtype indication these
1927 -- denote the lowest and highest values of the subtype
1929 Table
: Case_Table_Type
(0 .. Case_Table_Size
);
1930 -- Used to sort all the different choice values. Entry zero is
1931 -- reserved for sorting purposes.
1933 Single_Choice
: Boolean;
1934 -- Set to true every time there is a single discrete choice in a
1935 -- discrete association
1937 Prev_Nb_Discrete_Choices
: Nat
;
1938 -- Used to keep track of the number of discrete choices in the
1939 -- current association.
1941 Errors_Posted_On_Choices
: Boolean := False;
1942 -- Keeps track of whether any choices have semantic errors
1944 -- Start of processing for Step_2
1947 -- STEP 2 (A): Check discrete choices validity
1949 Assoc
:= First
(Component_Associations
(N
));
1950 while Present
(Assoc
) loop
1951 Prev_Nb_Discrete_Choices
:= Nb_Discrete_Choices
;
1952 Choice
:= First
(Choice_List
(Assoc
));
1957 if Nkind
(Choice
) = N_Others_Choice
then
1958 Single_Choice
:= False;
1961 -- Test for subtype mark without constraint
1963 elsif Is_Entity_Name
(Choice
) and then
1964 Is_Type
(Entity
(Choice
))
1966 if Base_Type
(Entity
(Choice
)) /= Index_Base
then
1968 ("invalid subtype mark in aggregate choice",
1973 -- Case of subtype indication
1975 elsif Nkind
(Choice
) = N_Subtype_Indication
then
1976 Resolve_Discrete_Subtype_Indication
(Choice
, Index_Base
);
1978 if Has_Dynamic_Predicate_Aspect
1979 (Entity
(Subtype_Mark
(Choice
)))
1982 ("subtype& has dynamic predicate, "
1983 & "not allowed in aggregate choice",
1984 Choice
, Entity
(Subtype_Mark
(Choice
)));
1987 -- Does the subtype indication evaluation raise CE?
1989 Get_Index_Bounds
(Subtype_Mark
(Choice
), S_Low
, S_High
);
1990 Get_Index_Bounds
(Choice
, Low
, High
);
1991 Check_Bounds
(S_Low
, S_High
, Low
, High
);
1993 -- Case of range or expression
1996 Resolve
(Choice
, Index_Base
);
1997 Check_Unset_Reference
(Choice
);
1998 Check_Non_Static_Context
(Choice
);
2000 -- If semantic errors were posted on the choice, then
2001 -- record that for possible early return from later
2002 -- processing (see handling of enumeration choices).
2004 if Error_Posted
(Choice
) then
2005 Errors_Posted_On_Choices
:= True;
2008 -- Do not range check a choice. This check is redundant
2009 -- since this test is already done when we check that the
2010 -- bounds of the array aggregate are within range.
2012 Set_Do_Range_Check
(Choice
, False);
2014 -- In SPARK, the choice must be static
2016 if not (Is_OK_Static_Expression
(Choice
)
2017 or else (Nkind
(Choice
) = N_Range
2018 and then Is_OK_Static_Range
(Choice
)))
2020 Check_SPARK_05_Restriction
2021 ("choice should be static", Choice
);
2025 -- If we could not resolve the discrete choice stop here
2027 if Etype
(Choice
) = Any_Type
then
2030 -- If the discrete choice raises CE get its original bounds
2032 elsif Nkind
(Choice
) = N_Raise_Constraint_Error
then
2033 Set_Raises_Constraint_Error
(N
);
2034 Get_Index_Bounds
(Original_Node
(Choice
), Low
, High
);
2036 -- Otherwise get its bounds as usual
2039 Get_Index_Bounds
(Choice
, Low
, High
);
2042 if (Dynamic_Or_Null_Range
(Low
, High
)
2043 or else (Nkind
(Choice
) = N_Subtype_Indication
2045 Dynamic_Or_Null_Range
(S_Low
, S_High
)))
2046 and then Nb_Choices
/= 1
2049 ("dynamic or empty choice in aggregate "
2050 & "must be the only choice", Choice
);
2054 if not (All_Composite_Constraints_Static
(Low
)
2055 and then All_Composite_Constraints_Static
(High
)
2056 and then All_Composite_Constraints_Static
(S_Low
)
2057 and then All_Composite_Constraints_Static
(S_High
))
2059 Check_Restriction
(No_Dynamic_Sized_Objects
, Choice
);
2062 Nb_Discrete_Choices
:= Nb_Discrete_Choices
+ 1;
2063 Table
(Nb_Discrete_Choices
).Lo
:= Low
;
2064 Table
(Nb_Discrete_Choices
).Hi
:= High
;
2065 Table
(Nb_Discrete_Choices
).Choice
:= Choice
;
2071 -- Check if we have a single discrete choice and whether
2072 -- this discrete choice specifies a single value.
2075 (Nb_Discrete_Choices
= Prev_Nb_Discrete_Choices
+ 1)
2076 and then (Low
= High
);
2082 -- Ada 2005 (AI-231)
2084 if Ada_Version
>= Ada_2005
2085 and then Known_Null
(Expression
(Assoc
))
2086 and then not Empty_Range
(Assoc
)
2088 Check_Can_Never_Be_Null
(Etype
(N
), Expression
(Assoc
));
2091 -- Ada 2005 (AI-287): In case of default initialized component
2092 -- we delay the resolution to the expansion phase.
2094 if Box_Present
(Assoc
) then
2096 -- Ada 2005 (AI-287): In case of default initialization of a
2097 -- component the expander will generate calls to the
2098 -- corresponding initialization subprogram. We need to call
2099 -- Resolve_Aggr_Expr to check the rules about
2102 if not Resolve_Aggr_Expr
2103 (Assoc
, Single_Elmt
=> Single_Choice
)
2108 elsif Nkind
(Assoc
) = N_Iterated_Component_Association
then
2109 null; -- handled above, in a loop context.
2111 elsif not Resolve_Aggr_Expr
2112 (Expression
(Assoc
), Single_Elmt
=> Single_Choice
)
2116 -- Check incorrect use of dynamically tagged expression
2118 -- We differentiate here two cases because the expression may
2119 -- not be decorated. For example, the analysis and resolution
2120 -- of the expression associated with the others choice will be
2121 -- done later with the full aggregate. In such case we
2122 -- duplicate the expression tree to analyze the copy and
2123 -- perform the required check.
2125 elsif not Present
(Etype
(Expression
(Assoc
))) then
2127 Save_Analysis
: constant Boolean := Full_Analysis
;
2128 Expr
: constant Node_Id
:=
2129 New_Copy_Tree
(Expression
(Assoc
));
2132 Expander_Mode_Save_And_Set
(False);
2133 Full_Analysis
:= False;
2135 -- Analyze the expression, making sure it is properly
2136 -- attached to the tree before we do the analysis.
2138 Set_Parent
(Expr
, Parent
(Expression
(Assoc
)));
2141 -- Compute its dimensions now, rather than at the end of
2142 -- resolution, because in the case of multidimensional
2143 -- aggregates subsequent expansion may lead to spurious
2146 Check_Expression_Dimensions
(Expr
, Component_Typ
);
2148 -- If the expression is a literal, propagate this info
2149 -- to the expression in the association, to enable some
2150 -- optimizations downstream.
2152 if Is_Entity_Name
(Expr
)
2153 and then Present
(Entity
(Expr
))
2154 and then Ekind
(Entity
(Expr
)) = E_Enumeration_Literal
2157 (Expression
(Assoc
), Component_Typ
);
2160 Full_Analysis
:= Save_Analysis
;
2161 Expander_Mode_Restore
;
2163 if Is_Tagged_Type
(Etype
(Expr
)) then
2164 Check_Dynamically_Tagged_Expression
2166 Typ
=> Component_Type
(Etype
(N
)),
2171 elsif Is_Tagged_Type
(Etype
(Expression
(Assoc
))) then
2172 Check_Dynamically_Tagged_Expression
2173 (Expr
=> Expression
(Assoc
),
2174 Typ
=> Component_Type
(Etype
(N
)),
2181 -- If aggregate contains more than one choice then these must be
2182 -- static. Check for duplicate and missing values.
2184 -- Note: there is duplicated code here wrt Check_Choice_Set in
2185 -- the body of Sem_Case, and it is possible we could just reuse
2186 -- that procedure. To be checked ???
2188 if Nb_Discrete_Choices
> 1 then
2189 Check_Choices
: declare
2191 -- Location of choice for messages
2195 -- High end of one range and Low end of the next. Should be
2196 -- contiguous if there is no hole in the list of values.
2200 -- End points of duplicated range
2202 Missing_Or_Duplicates
: Boolean := False;
2203 -- Set True if missing or duplicate choices found
2205 procedure Output_Bad_Choices
(Lo
, Hi
: Uint
; C
: Node_Id
);
2206 -- Output continuation message with a representation of the
2207 -- bounds (just Lo if Lo = Hi, else Lo .. Hi). C is the
2208 -- choice node where the message is to be posted.
2210 ------------------------
2211 -- Output_Bad_Choices --
2212 ------------------------
2214 procedure Output_Bad_Choices
(Lo
, Hi
: Uint
; C
: Node_Id
) is
2216 -- Enumeration type case
2218 if Is_Enumeration_Type
(Index_Typ
) then
2220 Chars
(Get_Enum_Lit_From_Pos
(Index_Typ
, Lo
, Loc
));
2222 Chars
(Get_Enum_Lit_From_Pos
(Index_Typ
, Hi
, Loc
));
2225 Error_Msg_N
("\\ %!", C
);
2227 Error_Msg_N
("\\ % .. %!", C
);
2230 -- Integer types case
2233 Error_Msg_Uint_1
:= Lo
;
2234 Error_Msg_Uint_2
:= Hi
;
2237 Error_Msg_N
("\\ ^!", C
);
2239 Error_Msg_N
("\\ ^ .. ^!", C
);
2242 end Output_Bad_Choices
;
2244 -- Start of processing for Check_Choices
2247 Sort_Case_Table
(Table
);
2249 -- First we do a quick linear loop to find out if we have
2250 -- any duplicates or missing entries (usually we have a
2251 -- legal aggregate, so this will get us out quickly).
2253 for J
in 1 .. Nb_Discrete_Choices
- 1 loop
2254 Hi_Val
:= Expr_Value
(Table
(J
).Hi
);
2255 Lo_Val
:= Expr_Value
(Table
(J
+ 1).Lo
);
2258 or else (Lo_Val
> Hi_Val
+ 1
2259 and then not Others_Present
)
2261 Missing_Or_Duplicates
:= True;
2266 -- If we have missing or duplicate entries, first fill in
2267 -- the Highest entries to make life easier in the following
2268 -- loops to detect bad entries.
2270 if Missing_Or_Duplicates
then
2271 Table
(1).Highest
:= Expr_Value
(Table
(1).Hi
);
2273 for J
in 2 .. Nb_Discrete_Choices
loop
2274 Table
(J
).Highest
:=
2276 (Table
(J
- 1).Highest
, Expr_Value
(Table
(J
).Hi
));
2279 -- Loop through table entries to find duplicate indexes
2281 for J
in 2 .. Nb_Discrete_Choices
loop
2282 Lo_Val
:= Expr_Value
(Table
(J
).Lo
);
2283 Hi_Val
:= Expr_Value
(Table
(J
).Hi
);
2285 -- Case where we have duplicates (the lower bound of
2286 -- this choice is less than or equal to the highest
2287 -- high bound found so far).
2289 if Lo_Val
<= Table
(J
- 1).Highest
then
2291 -- We move backwards looking for duplicates. We can
2292 -- abandon this loop as soon as we reach a choice
2293 -- highest value that is less than Lo_Val.
2295 for K
in reverse 1 .. J
- 1 loop
2296 exit when Table
(K
).Highest
< Lo_Val
;
2298 -- Here we may have duplicates between entries
2299 -- for K and J. Get range of duplicates.
2302 UI_Max
(Lo_Val
, Expr_Value
(Table
(K
).Lo
));
2304 UI_Min
(Hi_Val
, Expr_Value
(Table
(K
).Hi
));
2306 -- Nothing to do if duplicate range is null
2308 if Lo_Dup
> Hi_Dup
then
2311 -- Otherwise place proper message. Because
2312 -- of the missing expansion of subtypes with
2313 -- predicates in ASIS mode, do not report
2314 -- spurious overlap errors.
2318 ((Is_Type
(Entity
(Table
(J
).Choice
))
2319 and then Has_Predicates
2320 (Entity
(Table
(J
).Choice
)))
2322 (Is_Type
(Entity
(Table
(K
).Choice
))
2323 and then Has_Predicates
2324 (Entity
(Table
(K
).Choice
))))
2329 -- We place message on later choice, with a
2330 -- line reference to the earlier choice.
2332 if Sloc
(Table
(J
).Choice
) <
2333 Sloc
(Table
(K
).Choice
)
2335 Choice
:= Table
(K
).Choice
;
2336 Error_Msg_Sloc
:= Sloc
(Table
(J
).Choice
);
2338 Choice
:= Table
(J
).Choice
;
2339 Error_Msg_Sloc
:= Sloc
(Table
(K
).Choice
);
2342 if Lo_Dup
= Hi_Dup
then
2344 ("index value in array aggregate "
2345 & "duplicates the one given#!", Choice
);
2348 ("index values in array aggregate "
2349 & "duplicate those given#!", Choice
);
2352 Output_Bad_Choices
(Lo_Dup
, Hi_Dup
, Choice
);
2358 -- Loop through entries in table to find missing indexes.
2359 -- Not needed if others, since missing impossible.
2361 if not Others_Present
then
2362 for J
in 2 .. Nb_Discrete_Choices
loop
2363 Lo_Val
:= Expr_Value
(Table
(J
).Lo
);
2364 Hi_Val
:= Table
(J
- 1).Highest
;
2366 if Lo_Val
> Hi_Val
+ 1 then
2369 Error_Node
: Node_Id
;
2372 -- If the choice is the bound of a range in
2373 -- a subtype indication, it is not in the
2374 -- source lists for the aggregate itself, so
2375 -- post the error on the aggregate. Otherwise
2376 -- post it on choice itself.
2378 Choice
:= Table
(J
).Choice
;
2380 if Is_List_Member
(Choice
) then
2381 Error_Node
:= Choice
;
2386 if Hi_Val
+ 1 = Lo_Val
- 1 then
2388 ("missing index value "
2389 & "in array aggregate!", Error_Node
);
2392 ("missing index values "
2393 & "in array aggregate!", Error_Node
);
2397 (Hi_Val
+ 1, Lo_Val
- 1, Error_Node
);
2403 -- If either missing or duplicate values, return failure
2405 Set_Etype
(N
, Any_Composite
);
2411 -- STEP 2 (B): Compute aggregate bounds and min/max choices values
2413 if Nb_Discrete_Choices
> 0 then
2414 Choices_Low
:= Table
(1).Lo
;
2415 Choices_High
:= Table
(Nb_Discrete_Choices
).Hi
;
2418 -- If Others is present, then bounds of aggregate come from the
2419 -- index constraint (not the choices in the aggregate itself).
2421 if Others_Present
then
2422 Get_Index_Bounds
(Index_Constr
, Aggr_Low
, Aggr_High
);
2424 -- Abandon processing if either bound is already signalled as
2425 -- an error (prevents junk cascaded messages and blow ups).
2427 if Nkind
(Aggr_Low
) = N_Error
2429 Nkind
(Aggr_High
) = N_Error
2434 -- No others clause present
2437 -- Special processing if others allowed and not present. This
2438 -- means that the bounds of the aggregate come from the index
2439 -- constraint (and the length must match).
2441 if Others_Allowed
then
2442 Get_Index_Bounds
(Index_Constr
, Aggr_Low
, Aggr_High
);
2444 -- Abandon processing if either bound is already signalled
2445 -- as an error (stop junk cascaded messages and blow ups).
2447 if Nkind
(Aggr_Low
) = N_Error
2449 Nkind
(Aggr_High
) = N_Error
2454 -- If others allowed, and no others present, then the array
2455 -- should cover all index values. If it does not, we will
2456 -- get a length check warning, but there is two cases where
2457 -- an additional warning is useful:
2459 -- If we have no positional components, and the length is
2460 -- wrong (which we can tell by others being allowed with
2461 -- missing components), and the index type is an enumeration
2462 -- type, then issue appropriate warnings about these missing
2463 -- components. They are only warnings, since the aggregate
2464 -- is fine, it's just the wrong length. We skip this check
2465 -- for standard character types (since there are no literals
2466 -- and it is too much trouble to concoct them), and also if
2467 -- any of the bounds have values that are not known at
2470 -- Another case warranting a warning is when the length
2471 -- is right, but as above we have an index type that is
2472 -- an enumeration, and the bounds do not match. This is a
2473 -- case where dubious sliding is allowed and we generate a
2474 -- warning that the bounds do not match.
2476 if No
(Expressions
(N
))
2477 and then Nkind
(Index
) = N_Range
2478 and then Is_Enumeration_Type
(Etype
(Index
))
2479 and then not Is_Standard_Character_Type
(Etype
(Index
))
2480 and then Compile_Time_Known_Value
(Aggr_Low
)
2481 and then Compile_Time_Known_Value
(Aggr_High
)
2482 and then Compile_Time_Known_Value
(Choices_Low
)
2483 and then Compile_Time_Known_Value
(Choices_High
)
2485 -- If any of the expressions or range bounds in choices
2486 -- have semantic errors, then do not attempt further
2487 -- resolution, to prevent cascaded errors.
2489 if Errors_Posted_On_Choices
then
2494 ALo
: constant Node_Id
:= Expr_Value_E
(Aggr_Low
);
2495 AHi
: constant Node_Id
:= Expr_Value_E
(Aggr_High
);
2496 CLo
: constant Node_Id
:= Expr_Value_E
(Choices_Low
);
2497 CHi
: constant Node_Id
:= Expr_Value_E
(Choices_High
);
2502 -- Warning case 1, missing values at start/end. Only
2503 -- do the check if the number of entries is too small.
2505 if (Enumeration_Pos
(CHi
) - Enumeration_Pos
(CLo
))
2507 (Enumeration_Pos
(AHi
) - Enumeration_Pos
(ALo
))
2510 ("missing index value(s) in array aggregate??",
2513 -- Output missing value(s) at start
2515 if Chars
(ALo
) /= Chars
(CLo
) then
2518 if Chars
(ALo
) = Chars
(Ent
) then
2519 Error_Msg_Name_1
:= Chars
(ALo
);
2520 Error_Msg_N
("\ %??", N
);
2522 Error_Msg_Name_1
:= Chars
(ALo
);
2523 Error_Msg_Name_2
:= Chars
(Ent
);
2524 Error_Msg_N
("\ % .. %??", N
);
2528 -- Output missing value(s) at end
2530 if Chars
(AHi
) /= Chars
(CHi
) then
2533 if Chars
(AHi
) = Chars
(Ent
) then
2534 Error_Msg_Name_1
:= Chars
(Ent
);
2535 Error_Msg_N
("\ %??", N
);
2537 Error_Msg_Name_1
:= Chars
(Ent
);
2538 Error_Msg_Name_2
:= Chars
(AHi
);
2539 Error_Msg_N
("\ % .. %??", N
);
2543 -- Warning case 2, dubious sliding. The First_Subtype
2544 -- test distinguishes between a constrained type where
2545 -- sliding is not allowed (so we will get a warning
2546 -- later that Constraint_Error will be raised), and
2547 -- the unconstrained case where sliding is permitted.
2549 elsif (Enumeration_Pos
(CHi
) - Enumeration_Pos
(CLo
))
2551 (Enumeration_Pos
(AHi
) - Enumeration_Pos
(ALo
))
2552 and then Chars
(ALo
) /= Chars
(CLo
)
2554 not Is_Constrained
(First_Subtype
(Etype
(N
)))
2557 ("bounds of aggregate do not match target??", N
);
2563 -- If no others, aggregate bounds come from aggregate
2565 Aggr_Low
:= Choices_Low
;
2566 Aggr_High
:= Choices_High
;
2570 -- STEP 3: Process positional components
2573 -- STEP 3 (A): Process positional elements
2575 Expr
:= First
(Expressions
(N
));
2576 Nb_Elements
:= Uint_0
;
2577 while Present
(Expr
) loop
2578 Nb_Elements
:= Nb_Elements
+ 1;
2580 -- Ada 2005 (AI-231)
2582 if Ada_Version
>= Ada_2005
and then Known_Null
(Expr
) then
2583 Check_Can_Never_Be_Null
(Etype
(N
), Expr
);
2586 if not Resolve_Aggr_Expr
(Expr
, Single_Elmt
=> True) then
2590 -- Check incorrect use of dynamically tagged expression
2592 if Is_Tagged_Type
(Etype
(Expr
)) then
2593 Check_Dynamically_Tagged_Expression
2595 Typ
=> Component_Type
(Etype
(N
)),
2602 if Others_Present
then
2603 Assoc
:= Last
(Component_Associations
(N
));
2605 -- Ada 2005 (AI-231)
2607 if Ada_Version
>= Ada_2005
and then Known_Null
(Assoc
) then
2608 Check_Can_Never_Be_Null
(Etype
(N
), Expression
(Assoc
));
2611 -- Ada 2005 (AI-287): In case of default initialized component,
2612 -- we delay the resolution to the expansion phase.
2614 if Box_Present
(Assoc
) then
2616 -- Ada 2005 (AI-287): In case of default initialization of a
2617 -- component the expander will generate calls to the
2618 -- corresponding initialization subprogram. We need to call
2619 -- Resolve_Aggr_Expr to check the rules about
2622 if not Resolve_Aggr_Expr
(Assoc
, Single_Elmt
=> False) then
2626 elsif not Resolve_Aggr_Expr
(Expression
(Assoc
),
2627 Single_Elmt
=> False)
2631 -- Check incorrect use of dynamically tagged expression. The
2632 -- expression of the others choice has not been resolved yet.
2633 -- In order to diagnose the semantic error we create a duplicate
2634 -- tree to analyze it and perform the check.
2638 Save_Analysis
: constant Boolean := Full_Analysis
;
2639 Expr
: constant Node_Id
:=
2640 New_Copy_Tree
(Expression
(Assoc
));
2643 Expander_Mode_Save_And_Set
(False);
2644 Full_Analysis
:= False;
2646 Full_Analysis
:= Save_Analysis
;
2647 Expander_Mode_Restore
;
2649 if Is_Tagged_Type
(Etype
(Expr
)) then
2650 Check_Dynamically_Tagged_Expression
2652 Typ
=> Component_Type
(Etype
(N
)),
2659 -- STEP 3 (B): Compute the aggregate bounds
2661 if Others_Present
then
2662 Get_Index_Bounds
(Index_Constr
, Aggr_Low
, Aggr_High
);
2665 if Others_Allowed
then
2666 Get_Index_Bounds
(Index_Constr
, Aggr_Low
, Discard
);
2668 Aggr_Low
:= Index_Typ_Low
;
2671 Aggr_High
:= Add
(Nb_Elements
- 1, To
=> Aggr_Low
);
2672 Check_Bound
(Index_Base_High
, Aggr_High
);
2676 -- STEP 4: Perform static aggregate checks and save the bounds
2680 Check_Bounds
(Index_Typ_Low
, Index_Typ_High
, Aggr_Low
, Aggr_High
);
2681 Check_Bounds
(Index_Base_Low
, Index_Base_High
, Aggr_Low
, Aggr_High
);
2685 if Others_Present
and then Nb_Discrete_Choices
> 0 then
2686 Check_Bounds
(Aggr_Low
, Aggr_High
, Choices_Low
, Choices_High
);
2687 Check_Bounds
(Index_Typ_Low
, Index_Typ_High
,
2688 Choices_Low
, Choices_High
);
2689 Check_Bounds
(Index_Base_Low
, Index_Base_High
,
2690 Choices_Low
, Choices_High
);
2694 elsif Others_Present
and then Nb_Elements
> 0 then
2695 Check_Length
(Aggr_Low
, Aggr_High
, Nb_Elements
);
2696 Check_Length
(Index_Typ_Low
, Index_Typ_High
, Nb_Elements
);
2697 Check_Length
(Index_Base_Low
, Index_Base_High
, Nb_Elements
);
2700 if Raises_Constraint_Error
(Aggr_Low
)
2701 or else Raises_Constraint_Error
(Aggr_High
)
2703 Set_Raises_Constraint_Error
(N
);
2706 Aggr_Low
:= Duplicate_Subexpr
(Aggr_Low
);
2708 -- Do not duplicate Aggr_High if Aggr_High = Aggr_Low + Nb_Elements
2709 -- since the addition node returned by Add is not yet analyzed. Attach
2710 -- to tree and analyze first. Reset analyzed flag to ensure it will get
2711 -- analyzed when it is a literal bound whose type must be properly set.
2713 if Others_Present
or else Nb_Discrete_Choices
> 0 then
2714 Aggr_High
:= Duplicate_Subexpr
(Aggr_High
);
2716 if Etype
(Aggr_High
) = Universal_Integer
then
2717 Set_Analyzed
(Aggr_High
, False);
2721 -- If the aggregate already has bounds attached to it, it means this is
2722 -- a positional aggregate created as an optimization by
2723 -- Exp_Aggr.Convert_To_Positional, so we don't want to change those
2726 if Present
(Aggregate_Bounds
(N
)) and then not Others_Allowed
then
2727 Aggr_Low
:= Low_Bound
(Aggregate_Bounds
(N
));
2728 Aggr_High
:= High_Bound
(Aggregate_Bounds
(N
));
2731 Set_Aggregate_Bounds
2732 (N
, Make_Range
(Loc
, Low_Bound
=> Aggr_Low
, High_Bound
=> Aggr_High
));
2734 -- The bounds may contain expressions that must be inserted upwards.
2735 -- Attach them fully to the tree. After analysis, remove side effects
2736 -- from upper bound, if still needed.
2738 Set_Parent
(Aggregate_Bounds
(N
), N
);
2739 Analyze_And_Resolve
(Aggregate_Bounds
(N
), Index_Typ
);
2740 Check_Unset_Reference
(Aggregate_Bounds
(N
));
2742 if not Others_Present
and then Nb_Discrete_Choices
= 0 then
2744 (Aggregate_Bounds
(N
),
2745 Duplicate_Subexpr
(High_Bound
(Aggregate_Bounds
(N
))));
2748 -- Check the dimensions of each component in the array aggregate
2750 Analyze_Dimension_Array_Aggregate
(N
, Component_Typ
);
2753 end Resolve_Array_Aggregate
;
2755 -----------------------------
2756 -- Resolve_Delta_Aggregate --
2757 -----------------------------
2759 procedure Resolve_Delta_Aggregate
(N
: Node_Id
; Typ
: Entity_Id
) is
2760 Base
: constant Node_Id
:= Expression
(N
);
2761 Deltas
: constant List_Id
:= Component_Associations
(N
);
2763 function Get_Component_Type
(Nam
: Node_Id
) return Entity_Id
;
2765 ------------------------
2766 -- Get_Component_Type --
2767 ------------------------
2769 function Get_Component_Type
(Nam
: Node_Id
) return Entity_Id
is
2773 Comp
:= First_Entity
(Typ
);
2775 while Present
(Comp
) loop
2776 if Chars
(Comp
) = Chars
(Nam
) then
2777 if Ekind
(Comp
) = E_Discriminant
then
2778 Error_Msg_N
("delta cannot apply to discriminant", Nam
);
2781 return Etype
(Comp
);
2784 Comp
:= Next_Entity
(Comp
);
2787 Error_Msg_NE
("type& has no component with this name", Nam
, Typ
);
2789 end Get_Component_Type
;
2795 Comp_Type
: Entity_Id
;
2796 Index_Type
: Entity_Id
;
2798 -- Start of processing for Resolve_Delta_Aggregate
2801 if not Is_Composite_Type
(Typ
) then
2802 Error_Msg_N
("not a composite type", N
);
2805 Analyze_And_Resolve
(Base
, Typ
);
2807 if Is_Array_Type
(Typ
) then
2808 Index_Type
:= Etype
(First_Index
(Typ
));
2809 Assoc
:= First
(Deltas
);
2810 while Present
(Assoc
) loop
2811 if Nkind
(Assoc
) = N_Iterated_Component_Association
then
2812 Choice
:= First
(Choice_List
(Assoc
));
2813 while Present
(Choice
) loop
2814 if Nkind
(Choice
) = N_Others_Choice
then
2816 ("others not allowed in delta aggregate", Choice
);
2819 Analyze_And_Resolve
(Choice
, Index_Type
);
2826 Id
: constant Entity_Id
:= Defining_Identifier
(Assoc
);
2827 Ent
: constant Entity_Id
:=
2829 (E_Loop
, Current_Scope
, Sloc
(Assoc
), 'L');
2832 Set_Etype
(Ent
, Standard_Void_Type
);
2833 Set_Parent
(Ent
, Assoc
);
2835 if No
(Scope
(Id
)) then
2837 Set_Etype
(Id
, Index_Type
);
2838 Set_Ekind
(Id
, E_Variable
);
2839 Set_Scope
(Id
, Ent
);
2844 (New_Copy_Tree
(Expression
(Assoc
)), Component_Type
(Typ
));
2849 Choice
:= First
(Choice_List
(Assoc
));
2850 while Present
(Choice
) loop
2851 if Nkind
(Choice
) = N_Others_Choice
then
2853 ("others not allowed in delta aggregate", Choice
);
2857 if Is_Entity_Name
(Choice
)
2858 and then Is_Type
(Entity
(Choice
))
2860 -- Choice covers a range of values.
2861 if Base_Type
(Entity
(Choice
)) /=
2862 Base_Type
(Index_Type
)
2865 ("choice does mat match index type of",
2869 Resolve
(Choice
, Index_Type
);
2876 Analyze_And_Resolve
(Expression
(Assoc
), Component_Type
(Typ
));
2883 Assoc
:= First
(Deltas
);
2884 while Present
(Assoc
) loop
2885 Choice
:= First
(Choice_List
(Assoc
));
2886 while Present
(Choice
) loop
2887 Comp_Type
:= Get_Component_Type
(Choice
);
2891 Analyze_And_Resolve
(Expression
(Assoc
), Comp_Type
);
2897 end Resolve_Delta_Aggregate
;
2899 ---------------------------------
2900 -- Resolve_Extension_Aggregate --
2901 ---------------------------------
2903 -- There are two cases to consider:
2905 -- a) If the ancestor part is a type mark, the components needed are the
2906 -- difference between the components of the expected type and the
2907 -- components of the given type mark.
2909 -- b) If the ancestor part is an expression, it must be unambiguous, and
2910 -- once we have its type we can also compute the needed components as in
2911 -- the previous case. In both cases, if the ancestor type is not the
2912 -- immediate ancestor, we have to build this ancestor recursively.
2914 -- In both cases, discriminants of the ancestor type do not play a role in
2915 -- the resolution of the needed components, because inherited discriminants
2916 -- cannot be used in a type extension. As a result we can compute
2917 -- independently the list of components of the ancestor type and of the
2920 procedure Resolve_Extension_Aggregate
(N
: Node_Id
; Typ
: Entity_Id
) is
2921 A
: constant Node_Id
:= Ancestor_Part
(N
);
2926 function Valid_Limited_Ancestor
(Anc
: Node_Id
) return Boolean;
2927 -- If the type is limited, verify that the ancestor part is a legal
2928 -- expression (aggregate or function call, including 'Input)) that does
2929 -- not require a copy, as specified in 7.5(2).
2931 function Valid_Ancestor_Type
return Boolean;
2932 -- Verify that the type of the ancestor part is a non-private ancestor
2933 -- of the expected type, which must be a type extension.
2935 ----------------------------
2936 -- Valid_Limited_Ancestor --
2937 ----------------------------
2939 function Valid_Limited_Ancestor
(Anc
: Node_Id
) return Boolean is
2941 if Is_Entity_Name
(Anc
) and then Is_Type
(Entity
(Anc
)) then
2944 -- The ancestor must be a call or an aggregate, but a call may
2945 -- have been expanded into a temporary, so check original node.
2947 elsif Nkind_In
(Anc
, N_Aggregate
,
2948 N_Extension_Aggregate
,
2953 elsif Nkind
(Original_Node
(Anc
)) = N_Function_Call
then
2956 elsif Nkind
(Anc
) = N_Attribute_Reference
2957 and then Attribute_Name
(Anc
) = Name_Input
2961 elsif Nkind
(Anc
) = N_Qualified_Expression
then
2962 return Valid_Limited_Ancestor
(Expression
(Anc
));
2967 end Valid_Limited_Ancestor
;
2969 -------------------------
2970 -- Valid_Ancestor_Type --
2971 -------------------------
2973 function Valid_Ancestor_Type
return Boolean is
2974 Imm_Type
: Entity_Id
;
2977 Imm_Type
:= Base_Type
(Typ
);
2978 while Is_Derived_Type
(Imm_Type
) loop
2979 if Etype
(Imm_Type
) = Base_Type
(A_Type
) then
2982 -- The base type of the parent type may appear as a private
2983 -- extension if it is declared as such in a parent unit of the
2984 -- current one. For consistency of the subsequent analysis use
2985 -- the partial view for the ancestor part.
2987 elsif Is_Private_Type
(Etype
(Imm_Type
))
2988 and then Present
(Full_View
(Etype
(Imm_Type
)))
2989 and then Base_Type
(A_Type
) = Full_View
(Etype
(Imm_Type
))
2991 A_Type
:= Etype
(Imm_Type
);
2994 -- The parent type may be a private extension. The aggregate is
2995 -- legal if the type of the aggregate is an extension of it that
2996 -- is not a private extension.
2998 elsif Is_Private_Type
(A_Type
)
2999 and then not Is_Private_Type
(Imm_Type
)
3000 and then Present
(Full_View
(A_Type
))
3001 and then Base_Type
(Full_View
(A_Type
)) = Etype
(Imm_Type
)
3006 Imm_Type
:= Etype
(Base_Type
(Imm_Type
));
3010 -- If previous loop did not find a proper ancestor, report error
3012 Error_Msg_NE
("expect ancestor type of &", A
, Typ
);
3014 end Valid_Ancestor_Type
;
3016 -- Start of processing for Resolve_Extension_Aggregate
3019 -- Analyze the ancestor part and account for the case where it is a
3020 -- parameterless function call.
3023 Check_Parameterless_Call
(A
);
3025 -- In SPARK, the ancestor part cannot be a type mark
3027 if Is_Entity_Name
(A
) and then Is_Type
(Entity
(A
)) then
3028 Check_SPARK_05_Restriction
("ancestor part cannot be a type mark", A
);
3030 -- AI05-0115: if the ancestor part is a subtype mark, the ancestor
3031 -- must not have unknown discriminants.
3033 if Has_Unknown_Discriminants
(Root_Type
(Typ
)) then
3035 ("aggregate not available for type& whose ancestor "
3036 & "has unknown discriminants", N
, Typ
);
3040 if not Is_Tagged_Type
(Typ
) then
3041 Error_Msg_N
("type of extension aggregate must be tagged", N
);
3044 elsif Is_Limited_Type
(Typ
) then
3046 -- Ada 2005 (AI-287): Limited aggregates are allowed
3048 if Ada_Version
< Ada_2005
then
3049 Error_Msg_N
("aggregate type cannot be limited", N
);
3050 Explain_Limited_Type
(Typ
, N
);
3053 elsif Valid_Limited_Ancestor
(A
) then
3058 ("limited ancestor part must be aggregate or function call", A
);
3061 elsif Is_Class_Wide_Type
(Typ
) then
3062 Error_Msg_N
("aggregate cannot be of a class-wide type", N
);
3066 if Is_Entity_Name
(A
) and then Is_Type
(Entity
(A
)) then
3067 A_Type
:= Get_Full_View
(Entity
(A
));
3069 if Valid_Ancestor_Type
then
3070 Set_Entity
(A
, A_Type
);
3071 Set_Etype
(A
, A_Type
);
3073 Validate_Ancestor_Part
(N
);
3074 Resolve_Record_Aggregate
(N
, Typ
);
3077 elsif Nkind
(A
) /= N_Aggregate
then
3078 if Is_Overloaded
(A
) then
3081 Get_First_Interp
(A
, I
, It
);
3082 while Present
(It
.Typ
) loop
3084 -- Only consider limited interpretations in the Ada 2005 case
3086 if Is_Tagged_Type
(It
.Typ
)
3087 and then (Ada_Version
>= Ada_2005
3088 or else not Is_Limited_Type
(It
.Typ
))
3090 if A_Type
/= Any_Type
then
3091 Error_Msg_N
("cannot resolve expression", A
);
3098 Get_Next_Interp
(I
, It
);
3101 if A_Type
= Any_Type
then
3102 if Ada_Version
>= Ada_2005
then
3104 ("ancestor part must be of a tagged type", A
);
3107 ("ancestor part must be of a nonlimited tagged type", A
);
3114 A_Type
:= Etype
(A
);
3117 if Valid_Ancestor_Type
then
3118 Resolve
(A
, A_Type
);
3119 Check_Unset_Reference
(A
);
3120 Check_Non_Static_Context
(A
);
3122 -- The aggregate is illegal if the ancestor expression is a call
3123 -- to a function with a limited unconstrained result, unless the
3124 -- type of the aggregate is a null extension. This restriction
3125 -- was added in AI05-67 to simplify implementation.
3127 if Nkind
(A
) = N_Function_Call
3128 and then Is_Limited_Type
(A_Type
)
3129 and then not Is_Null_Extension
(Typ
)
3130 and then not Is_Constrained
(A_Type
)
3133 ("type of limited ancestor part must be constrained", A
);
3135 -- Reject the use of CPP constructors that leave objects partially
3136 -- initialized. For example:
3138 -- type CPP_Root is tagged limited record ...
3139 -- pragma Import (CPP, CPP_Root);
3141 -- type CPP_DT is new CPP_Root and Iface ...
3142 -- pragma Import (CPP, CPP_DT);
3144 -- type Ada_DT is new CPP_DT with ...
3146 -- Obj : Ada_DT := Ada_DT'(New_CPP_Root with others => <>);
3148 -- Using the constructor of CPP_Root the slots of the dispatch
3149 -- table of CPP_DT cannot be set, and the secondary tag of
3150 -- CPP_DT is unknown.
3152 elsif Nkind
(A
) = N_Function_Call
3153 and then Is_CPP_Constructor_Call
(A
)
3154 and then Enclosing_CPP_Parent
(Typ
) /= A_Type
3157 ("??must use 'C'P'P constructor for type &", A
,
3158 Enclosing_CPP_Parent
(Typ
));
3160 -- The following call is not needed if the previous warning
3161 -- is promoted to an error.
3163 Resolve_Record_Aggregate
(N
, Typ
);
3165 elsif Is_Class_Wide_Type
(Etype
(A
))
3166 and then Nkind
(Original_Node
(A
)) = N_Function_Call
3168 -- If the ancestor part is a dispatching call, it appears
3169 -- statically to be a legal ancestor, but it yields any member
3170 -- of the class, and it is not possible to determine whether
3171 -- it is an ancestor of the extension aggregate (much less
3172 -- which ancestor). It is not possible to determine the
3173 -- components of the extension part.
3175 -- This check implements AI-306, which in fact was motivated by
3176 -- an AdaCore query to the ARG after this test was added.
3178 Error_Msg_N
("ancestor part must be statically tagged", A
);
3180 Resolve_Record_Aggregate
(N
, Typ
);
3185 Error_Msg_N
("no unique type for this aggregate", A
);
3188 Check_Function_Writable_Actuals
(N
);
3189 end Resolve_Extension_Aggregate
;
3191 ------------------------------
3192 -- Resolve_Record_Aggregate --
3193 ------------------------------
3195 procedure Resolve_Record_Aggregate
(N
: Node_Id
; Typ
: Entity_Id
) is
3196 New_Assoc_List
: constant List_Id
:= New_List
;
3197 -- New_Assoc_List is the newly built list of N_Component_Association
3200 Others_Etype
: Entity_Id
:= Empty
;
3201 -- This variable is used to save the Etype of the last record component
3202 -- that takes its value from the others choice. Its purpose is:
3204 -- (a) make sure the others choice is useful
3206 -- (b) make sure the type of all the components whose value is
3207 -- subsumed by the others choice are the same.
3209 -- This variable is updated as a side effect of function Get_Value.
3211 Box_Node
: Node_Id
:= Empty
;
3212 Is_Box_Present
: Boolean := False;
3213 Others_Box
: Integer := 0;
3214 -- Ada 2005 (AI-287): Variables used in case of default initialization
3215 -- to provide a functionality similar to Others_Etype. Box_Present
3216 -- indicates that the component takes its default initialization;
3217 -- Others_Box counts the number of components of the current aggregate
3218 -- (which may be a sub-aggregate of a larger one) that are default-
3219 -- initialized. A value of One indicates that an others_box is present.
3220 -- Any larger value indicates that the others_box is not redundant.
3221 -- These variables, similar to Others_Etype, are also updated as a side
3222 -- effect of function Get_Value. Box_Node is used to place a warning on
3223 -- a redundant others_box.
3225 procedure Add_Association
3226 (Component
: Entity_Id
;
3228 Assoc_List
: List_Id
;
3229 Is_Box_Present
: Boolean := False);
3230 -- Builds a new N_Component_Association node which associates Component
3231 -- to expression Expr and adds it to the association list being built,
3232 -- either New_Assoc_List, or the association being built for an inner
3235 procedure Add_Discriminant_Values
3236 (New_Aggr
: Node_Id
;
3237 Assoc_List
: List_Id
);
3238 -- The constraint to a component may be given by a discriminant of the
3239 -- enclosing type, in which case we have to retrieve its value, which is
3240 -- part of the enclosing aggregate. Assoc_List provides the discriminant
3241 -- associations of the current type or of some enclosing record.
3243 function Discriminant_Present
(Input_Discr
: Entity_Id
) return Boolean;
3244 -- If aggregate N is a regular aggregate this routine will return True.
3245 -- Otherwise, if N is an extension aggregate, then Input_Discr denotes
3246 -- a discriminant whose value may already have been specified by N's
3247 -- ancestor part. This routine checks whether this is indeed the case
3248 -- and if so returns False, signaling that no value for Input_Discr
3249 -- should appear in N's aggregate part. Also, in this case, the routine
3250 -- appends to New_Assoc_List the discriminant value specified in the
3253 -- If the aggregate is in a context with expansion delayed, it will be
3254 -- reanalyzed. The inherited discriminant values must not be reinserted
3255 -- in the component list to prevent spurious errors, but they must be
3256 -- present on first analysis to build the proper subtype indications.
3257 -- The flag Inherited_Discriminant is used to prevent the re-insertion.
3259 function Find_Private_Ancestor
(Typ
: Entity_Id
) return Entity_Id
;
3260 -- AI05-0115: Find earlier ancestor in the derivation chain that is
3261 -- derived from private view Typ. Whether the aggregate is legal depends
3262 -- on the current visibility of the type as well as that of the parent
3268 Consider_Others_Choice
: Boolean := False) return Node_Id
;
3269 -- Given a record component stored in parameter Compon, this function
3270 -- returns its value as it appears in the list From, which is a list
3271 -- of N_Component_Association nodes.
3273 -- If no component association has a choice for the searched component,
3274 -- the value provided by the others choice is returned, if there is one,
3275 -- and Consider_Others_Choice is set to true. Otherwise Empty is
3276 -- returned. If there is more than one component association giving a
3277 -- value for the searched record component, an error message is emitted
3278 -- and the first found value is returned.
3280 -- If Consider_Others_Choice is set and the returned expression comes
3281 -- from the others choice, then Others_Etype is set as a side effect.
3282 -- An error message is emitted if the components taking their value from
3283 -- the others choice do not have same type.
3285 procedure Propagate_Discriminants
3287 Assoc_List
: List_Id
);
3288 -- Nested components may themselves be discriminated types constrained
3289 -- by outer discriminants, whose values must be captured before the
3290 -- aggregate is expanded into assignments.
3292 procedure Resolve_Aggr_Expr
(Expr
: Node_Id
; Component
: Entity_Id
);
3293 -- Analyzes and resolves expression Expr against the Etype of the
3294 -- Component. This routine also applies all appropriate checks to Expr.
3295 -- It finally saves a Expr in the newly created association list that
3296 -- will be attached to the final record aggregate. Note that if the
3297 -- Parent pointer of Expr is not set then Expr was produced with a
3298 -- New_Copy_Tree or some such.
3300 procedure Rewrite_Range
(Root_Type
: Entity_Id
; Rge
: Node_Id
);
3301 -- Rewrite a range node Rge when its bounds refer to non-stored
3302 -- discriminants from Root_Type, to replace them with the stored
3303 -- discriminant values. This is required in GNATprove mode, and is
3304 -- adopted in all modes to avoid special-casing GNATprove mode.
3306 ---------------------
3307 -- Add_Association --
3308 ---------------------
3310 procedure Add_Association
3311 (Component
: Entity_Id
;
3313 Assoc_List
: List_Id
;
3314 Is_Box_Present
: Boolean := False)
3316 Choice_List
: constant List_Id
:= New_List
;
3320 -- If this is a box association the expression is missing, so use the
3321 -- Sloc of the aggregate itself for the new association.
3323 if Present
(Expr
) then
3329 Append_To
(Choice_List
, New_Occurrence_Of
(Component
, Loc
));
3331 Append_To
(Assoc_List
,
3332 Make_Component_Association
(Loc
,
3333 Choices
=> Choice_List
,
3335 Box_Present
=> Is_Box_Present
));
3336 end Add_Association
;
3338 -----------------------------
3339 -- Add_Discriminant_Values --
3340 -----------------------------
3342 procedure Add_Discriminant_Values
3343 (New_Aggr
: Node_Id
;
3344 Assoc_List
: List_Id
)
3348 Discr_Elmt
: Elmt_Id
;
3349 Discr_Val
: Node_Id
;
3353 Discr
:= First_Discriminant
(Etype
(New_Aggr
));
3354 Discr_Elmt
:= First_Elmt
(Discriminant_Constraint
(Etype
(New_Aggr
)));
3355 while Present
(Discr_Elmt
) loop
3356 Discr_Val
:= Node
(Discr_Elmt
);
3358 -- If the constraint is given by a discriminant then it is a
3359 -- discriminant of an enclosing record, and its value has already
3360 -- been placed in the association list.
3362 if Is_Entity_Name
(Discr_Val
)
3363 and then Ekind
(Entity
(Discr_Val
)) = E_Discriminant
3365 Val
:= Entity
(Discr_Val
);
3367 Assoc
:= First
(Assoc_List
);
3368 while Present
(Assoc
) loop
3369 if Present
(Entity
(First
(Choices
(Assoc
))))
3370 and then Entity
(First
(Choices
(Assoc
))) = Val
3372 Discr_Val
:= Expression
(Assoc
);
3381 (Discr
, New_Copy_Tree
(Discr_Val
),
3382 Component_Associations
(New_Aggr
));
3384 -- If the discriminant constraint is a current instance, mark the
3385 -- current aggregate so that the self-reference can be expanded
3386 -- later. The constraint may refer to the subtype of aggregate, so
3387 -- use base type for comparison.
3389 if Nkind
(Discr_Val
) = N_Attribute_Reference
3390 and then Is_Entity_Name
(Prefix
(Discr_Val
))
3391 and then Is_Type
(Entity
(Prefix
(Discr_Val
)))
3392 and then Base_Type
(Etype
(N
)) = Entity
(Prefix
(Discr_Val
))
3394 Set_Has_Self_Reference
(N
);
3397 Next_Elmt
(Discr_Elmt
);
3398 Next_Discriminant
(Discr
);
3400 end Add_Discriminant_Values
;
3402 --------------------------
3403 -- Discriminant_Present --
3404 --------------------------
3406 function Discriminant_Present
(Input_Discr
: Entity_Id
) return Boolean is
3407 Regular_Aggr
: constant Boolean := Nkind
(N
) /= N_Extension_Aggregate
;
3409 Ancestor_Is_Subtyp
: Boolean;
3414 Ancestor_Typ
: Entity_Id
;
3415 Comp_Assoc
: Node_Id
;
3417 Discr_Expr
: Node_Id
;
3418 Discr_Val
: Elmt_Id
:= No_Elmt
;
3419 Orig_Discr
: Entity_Id
;
3422 if Regular_Aggr
then
3426 -- Check whether inherited discriminant values have already been
3427 -- inserted in the aggregate. This will be the case if we are
3428 -- re-analyzing an aggregate whose expansion was delayed.
3430 if Present
(Component_Associations
(N
)) then
3431 Comp_Assoc
:= First
(Component_Associations
(N
));
3432 while Present
(Comp_Assoc
) loop
3433 if Inherited_Discriminant
(Comp_Assoc
) then
3441 Ancestor
:= Ancestor_Part
(N
);
3442 Ancestor_Typ
:= Etype
(Ancestor
);
3443 Loc
:= Sloc
(Ancestor
);
3445 -- For a private type with unknown discriminants, use the underlying
3446 -- record view if it is available.
3448 if Has_Unknown_Discriminants
(Ancestor_Typ
)
3449 and then Present
(Full_View
(Ancestor_Typ
))
3450 and then Present
(Underlying_Record_View
(Full_View
(Ancestor_Typ
)))
3452 Ancestor_Typ
:= Underlying_Record_View
(Full_View
(Ancestor_Typ
));
3455 Ancestor_Is_Subtyp
:=
3456 Is_Entity_Name
(Ancestor
) and then Is_Type
(Entity
(Ancestor
));
3458 -- If the ancestor part has no discriminants clearly N's aggregate
3459 -- part must provide a value for Discr.
3461 if not Has_Discriminants
(Ancestor_Typ
) then
3464 -- If the ancestor part is an unconstrained subtype mark then the
3465 -- Discr must be present in N's aggregate part.
3467 elsif Ancestor_Is_Subtyp
3468 and then not Is_Constrained
(Entity
(Ancestor
))
3473 -- Now look to see if Discr was specified in the ancestor part
3475 if Ancestor_Is_Subtyp
then
3477 First_Elmt
(Discriminant_Constraint
(Entity
(Ancestor
)));
3480 Orig_Discr
:= Original_Record_Component
(Input_Discr
);
3482 Discr
:= First_Discriminant
(Ancestor_Typ
);
3483 while Present
(Discr
) loop
3485 -- If Ancestor has already specified Disc value then insert its
3486 -- value in the final aggregate.
3488 if Original_Record_Component
(Discr
) = Orig_Discr
then
3489 if Ancestor_Is_Subtyp
then
3490 Discr_Expr
:= New_Copy_Tree
(Node
(Discr_Val
));
3493 Make_Selected_Component
(Loc
,
3494 Prefix
=> Duplicate_Subexpr
(Ancestor
),
3495 Selector_Name
=> New_Occurrence_Of
(Input_Discr
, Loc
));
3498 Resolve_Aggr_Expr
(Discr_Expr
, Input_Discr
);
3499 Set_Inherited_Discriminant
(Last
(New_Assoc_List
));
3503 Next_Discriminant
(Discr
);
3505 if Ancestor_Is_Subtyp
then
3506 Next_Elmt
(Discr_Val
);
3511 end Discriminant_Present
;
3513 ---------------------------
3514 -- Find_Private_Ancestor --
3515 ---------------------------
3517 function Find_Private_Ancestor
(Typ
: Entity_Id
) return Entity_Id
is
3523 if Has_Private_Ancestor
(Par
)
3524 and then not Has_Private_Ancestor
(Etype
(Base_Type
(Par
)))
3528 elsif not Is_Derived_Type
(Par
) then
3532 Par
:= Etype
(Base_Type
(Par
));
3535 end Find_Private_Ancestor
;
3544 Consider_Others_Choice
: Boolean := False) return Node_Id
3546 Typ
: constant Entity_Id
:= Etype
(Compon
);
3548 Expr
: Node_Id
:= Empty
;
3549 Selector_Name
: Node_Id
;
3552 Is_Box_Present
:= False;
3558 Assoc
:= First
(From
);
3559 while Present
(Assoc
) loop
3560 Selector_Name
:= First
(Choices
(Assoc
));
3561 while Present
(Selector_Name
) loop
3562 if Nkind
(Selector_Name
) = N_Others_Choice
then
3563 if Consider_Others_Choice
and then No
(Expr
) then
3565 -- We need to duplicate the expression for each
3566 -- successive component covered by the others choice.
3567 -- This is redundant if the others_choice covers only
3568 -- one component (small optimization possible???), but
3569 -- indispensable otherwise, because each one must be
3570 -- expanded individually to preserve side-effects.
3572 -- Ada 2005 (AI-287): In case of default initialization
3573 -- of components, we duplicate the corresponding default
3574 -- expression (from the record type declaration). The
3575 -- copy must carry the sloc of the association (not the
3576 -- original expression) to prevent spurious elaboration
3577 -- checks when the default includes function calls.
3579 if Box_Present
(Assoc
) then
3580 Others_Box
:= Others_Box
+ 1;
3581 Is_Box_Present
:= True;
3583 if Expander_Active
then
3585 New_Copy_Tree_And_Copy_Dimensions
3586 (Expression
(Parent
(Compon
)),
3587 New_Sloc
=> Sloc
(Assoc
));
3589 return Expression
(Parent
(Compon
));
3593 if Present
(Others_Etype
)
3594 and then Base_Type
(Others_Etype
) /= Base_Type
(Typ
)
3596 -- If the components are of an anonymous access
3597 -- type they are distinct, but this is legal in
3598 -- Ada 2012 as long as designated types match.
3600 if (Ekind
(Typ
) = E_Anonymous_Access_Type
3601 or else Ekind
(Typ
) =
3602 E_Anonymous_Access_Subprogram_Type
)
3603 and then Designated_Type
(Typ
) =
3604 Designated_Type
(Others_Etype
)
3609 ("components in OTHERS choice must have same "
3610 & "type", Selector_Name
);
3614 Others_Etype
:= Typ
;
3616 -- Copy the expression so that it is resolved
3617 -- independently for each component, This is needed
3618 -- for accessibility checks on compoents of anonymous
3619 -- access types, even in compile_only mode.
3621 if not Inside_A_Generic
then
3623 -- In ASIS mode, preanalyze the expression in an
3624 -- others association before making copies for
3625 -- separate resolution and accessibility checks.
3626 -- This ensures that the type of the expression is
3627 -- available to ASIS in all cases, in particular if
3628 -- the expression is itself an aggregate.
3631 Preanalyze_And_Resolve
(Expression
(Assoc
), Typ
);
3635 New_Copy_Tree_And_Copy_Dimensions
3636 (Expression
(Assoc
));
3639 return Expression
(Assoc
);
3644 elsif Chars
(Compon
) = Chars
(Selector_Name
) then
3647 -- Ada 2005 (AI-231)
3649 if Ada_Version
>= Ada_2005
3650 and then Known_Null
(Expression
(Assoc
))
3652 Check_Can_Never_Be_Null
(Compon
, Expression
(Assoc
));
3655 -- We need to duplicate the expression when several
3656 -- components are grouped together with a "|" choice.
3657 -- For instance "filed1 | filed2 => Expr"
3659 -- Ada 2005 (AI-287)
3661 if Box_Present
(Assoc
) then
3662 Is_Box_Present
:= True;
3664 -- Duplicate the default expression of the component
3665 -- from the record type declaration, so a new copy
3666 -- can be attached to the association.
3668 -- Note that we always copy the default expression,
3669 -- even when the association has a single choice, in
3670 -- order to create a proper association for the
3671 -- expanded aggregate.
3673 -- Component may have no default, in which case the
3674 -- expression is empty and the component is default-
3675 -- initialized, but an association for the component
3676 -- exists, and it is not covered by an others clause.
3678 -- Scalar and private types have no initialization
3679 -- procedure, so they remain uninitialized. If the
3680 -- target of the aggregate is a constant this
3681 -- deserves a warning.
3683 if No
(Expression
(Parent
(Compon
)))
3684 and then not Has_Non_Null_Base_Init_Proc
(Typ
)
3685 and then not Has_Aspect
(Typ
, Aspect_Default_Value
)
3686 and then not Is_Concurrent_Type
(Typ
)
3687 and then Nkind
(Parent
(N
)) = N_Object_Declaration
3688 and then Constant_Present
(Parent
(N
))
3690 Error_Msg_Node_2
:= Typ
;
3692 ("component&? of type& is uninitialized",
3693 Assoc
, Selector_Name
);
3695 -- An additional reminder if the component type
3696 -- is a generic formal.
3698 if Is_Generic_Type
(Base_Type
(Typ
)) then
3700 ("\instance should provide actual type with "
3701 & "initialization for&", Assoc
, Typ
);
3706 New_Copy_Tree_And_Copy_Dimensions
3707 (Expression
(Parent
(Compon
)));
3710 if Present
(Next
(Selector_Name
)) then
3711 Expr
:= New_Copy_Tree_And_Copy_Dimensions
3712 (Expression
(Assoc
));
3714 Expr
:= Expression
(Assoc
);
3718 Generate_Reference
(Compon
, Selector_Name
, 'm');
3722 ("more than one value supplied for &",
3723 Selector_Name
, Compon
);
3728 Next
(Selector_Name
);
3737 -----------------------------
3738 -- Propagate_Discriminants --
3739 -----------------------------
3741 procedure Propagate_Discriminants
3743 Assoc_List
: List_Id
)
3745 Loc
: constant Source_Ptr
:= Sloc
(N
);
3747 Needs_Box
: Boolean := False;
3749 procedure Process_Component
(Comp
: Entity_Id
);
3750 -- Add one component with a box association to the inner aggregate,
3751 -- and recurse if component is itself composite.
3753 -----------------------
3754 -- Process_Component --
3755 -----------------------
3757 procedure Process_Component
(Comp
: Entity_Id
) is
3758 T
: constant Entity_Id
:= Etype
(Comp
);
3762 if Is_Record_Type
(T
) and then Has_Discriminants
(T
) then
3763 New_Aggr
:= Make_Aggregate
(Loc
, New_List
, New_List
);
3764 Set_Etype
(New_Aggr
, T
);
3767 (Comp
, New_Aggr
, Component_Associations
(Aggr
));
3769 -- Collect discriminant values and recurse
3771 Add_Discriminant_Values
(New_Aggr
, Assoc_List
);
3772 Propagate_Discriminants
(New_Aggr
, Assoc_List
);
3777 end Process_Component
;
3781 Aggr_Type
: constant Entity_Id
:= Base_Type
(Etype
(Aggr
));
3782 Components
: constant Elist_Id
:= New_Elmt_List
;
3783 Def_Node
: constant Node_Id
:=
3784 Type_Definition
(Declaration_Node
(Aggr_Type
));
3787 Comp_Elmt
: Elmt_Id
;
3790 -- Start of processing for Propagate_Discriminants
3793 -- The component type may be a variant type. Collect the components
3794 -- that are ruled by the known values of the discriminants. Their
3795 -- values have already been inserted into the component list of the
3796 -- current aggregate.
3798 if Nkind
(Def_Node
) = N_Record_Definition
3799 and then Present
(Component_List
(Def_Node
))
3800 and then Present
(Variant_Part
(Component_List
(Def_Node
)))
3802 Gather_Components
(Aggr_Type
,
3803 Component_List
(Def_Node
),
3804 Governed_By
=> Component_Associations
(Aggr
),
3806 Report_Errors
=> Errors
);
3808 Comp_Elmt
:= First_Elmt
(Components
);
3809 while Present
(Comp_Elmt
) loop
3810 if Ekind
(Node
(Comp_Elmt
)) /= E_Discriminant
then
3811 Process_Component
(Node
(Comp_Elmt
));
3814 Next_Elmt
(Comp_Elmt
);
3817 -- No variant part, iterate over all components
3820 Comp
:= First_Component
(Etype
(Aggr
));
3821 while Present
(Comp
) loop
3822 Process_Component
(Comp
);
3823 Next_Component
(Comp
);
3828 Append_To
(Component_Associations
(Aggr
),
3829 Make_Component_Association
(Loc
,
3830 Choices
=> New_List
(Make_Others_Choice
(Loc
)),
3831 Expression
=> Empty
,
3832 Box_Present
=> True));
3834 end Propagate_Discriminants
;
3836 -----------------------
3837 -- Resolve_Aggr_Expr --
3838 -----------------------
3840 procedure Resolve_Aggr_Expr
(Expr
: Node_Id
; Component
: Entity_Id
) is
3841 function Has_Expansion_Delayed
(Expr
: Node_Id
) return Boolean;
3842 -- If the expression is an aggregate (possibly qualified) then its
3843 -- expansion is delayed until the enclosing aggregate is expanded
3844 -- into assignments. In that case, do not generate checks on the
3845 -- expression, because they will be generated later, and will other-
3846 -- wise force a copy (to remove side-effects) that would leave a
3847 -- dynamic-sized aggregate in the code, something that gigi cannot
3850 ---------------------------
3851 -- Has_Expansion_Delayed --
3852 ---------------------------
3854 function Has_Expansion_Delayed
(Expr
: Node_Id
) return Boolean is
3857 (Nkind_In
(Expr
, N_Aggregate
, N_Extension_Aggregate
)
3858 and then Present
(Etype
(Expr
))
3859 and then Is_Record_Type
(Etype
(Expr
))
3860 and then Expansion_Delayed
(Expr
))
3862 (Nkind
(Expr
) = N_Qualified_Expression
3863 and then Has_Expansion_Delayed
(Expression
(Expr
)));
3864 end Has_Expansion_Delayed
;
3868 Expr_Type
: Entity_Id
:= Empty
;
3869 New_C
: Entity_Id
:= Component
;
3873 -- Set to True if the resolved Expr node needs to be relocated when
3874 -- attached to the newly created association list. This node need not
3875 -- be relocated if its parent pointer is not set. In fact in this
3876 -- case Expr is the output of a New_Copy_Tree call. If Relocate is
3877 -- True then we have analyzed the expression node in the original
3878 -- aggregate and hence it needs to be relocated when moved over to
3879 -- the new association list.
3881 -- Start of processing for Resolve_Aggr_Expr
3884 -- If the type of the component is elementary or the type of the
3885 -- aggregate does not contain discriminants, use the type of the
3886 -- component to resolve Expr.
3888 if Is_Elementary_Type
(Etype
(Component
))
3889 or else not Has_Discriminants
(Etype
(N
))
3891 Expr_Type
:= Etype
(Component
);
3893 -- Otherwise we have to pick up the new type of the component from
3894 -- the new constrained subtype of the aggregate. In fact components
3895 -- which are of a composite type might be constrained by a
3896 -- discriminant, and we want to resolve Expr against the subtype were
3897 -- all discriminant occurrences are replaced with their actual value.
3900 New_C
:= First_Component
(Etype
(N
));
3901 while Present
(New_C
) loop
3902 if Chars
(New_C
) = Chars
(Component
) then
3903 Expr_Type
:= Etype
(New_C
);
3907 Next_Component
(New_C
);
3910 pragma Assert
(Present
(Expr_Type
));
3912 -- For each range in an array type where a discriminant has been
3913 -- replaced with the constraint, check that this range is within
3914 -- the range of the base type. This checks is done in the init
3915 -- proc for regular objects, but has to be done here for
3916 -- aggregates since no init proc is called for them.
3918 if Is_Array_Type
(Expr_Type
) then
3921 -- Range of the current constrained index in the array
3923 Orig_Index
: Node_Id
:= First_Index
(Etype
(Component
));
3924 -- Range corresponding to the range Index above in the
3925 -- original unconstrained record type. The bounds of this
3926 -- range may be governed by discriminants.
3928 Unconstr_Index
: Node_Id
:= First_Index
(Etype
(Expr_Type
));
3929 -- Range corresponding to the range Index above for the
3930 -- unconstrained array type. This range is needed to apply
3934 Index
:= First_Index
(Expr_Type
);
3935 while Present
(Index
) loop
3936 if Depends_On_Discriminant
(Orig_Index
) then
3937 Apply_Range_Check
(Index
, Etype
(Unconstr_Index
));
3941 Next_Index
(Orig_Index
);
3942 Next_Index
(Unconstr_Index
);
3948 -- If the Parent pointer of Expr is not set, Expr is an expression
3949 -- duplicated by New_Tree_Copy (this happens for record aggregates
3950 -- that look like (Field1 | Filed2 => Expr) or (others => Expr)).
3951 -- Such a duplicated expression must be attached to the tree
3952 -- before analysis and resolution to enforce the rule that a tree
3953 -- fragment should never be analyzed or resolved unless it is
3954 -- attached to the current compilation unit.
3956 if No
(Parent
(Expr
)) then
3957 Set_Parent
(Expr
, N
);
3963 Analyze_And_Resolve
(Expr
, Expr_Type
);
3964 Check_Expr_OK_In_Limited_Aggregate
(Expr
);
3965 Check_Non_Static_Context
(Expr
);
3966 Check_Unset_Reference
(Expr
);
3968 -- Check wrong use of class-wide types
3970 if Is_Class_Wide_Type
(Etype
(Expr
)) then
3971 Error_Msg_N
("dynamically tagged expression not allowed", Expr
);
3974 if not Has_Expansion_Delayed
(Expr
) then
3975 Aggregate_Constraint_Checks
(Expr
, Expr_Type
);
3978 -- If an aggregate component has a type with predicates, an explicit
3979 -- predicate check must be applied, as for an assignment statement,
3980 -- because the aggegate might not be expanded into individual
3981 -- component assignments.
3983 if Present
(Predicate_Function
(Expr_Type
))
3984 and then Analyzed
(Expr
)
3986 Apply_Predicate_Check
(Expr
, Expr_Type
);
3989 if Raises_Constraint_Error
(Expr
) then
3990 Set_Raises_Constraint_Error
(N
);
3993 -- If the expression has been marked as requiring a range check, then
3994 -- generate it here. It's a bit odd to be generating such checks in
3995 -- the analyzer, but harmless since Generate_Range_Check does nothing
3996 -- (other than making sure Do_Range_Check is set) if the expander is
3999 if Do_Range_Check
(Expr
) then
4000 Generate_Range_Check
(Expr
, Expr_Type
, CE_Range_Check_Failed
);
4003 -- Add association Component => Expr if the caller requests it
4006 New_Expr
:= Relocate_Node
(Expr
);
4008 -- Since New_Expr is not gonna be analyzed later on, we need to
4009 -- propagate here the dimensions form Expr to New_Expr.
4011 Copy_Dimensions
(Expr
, New_Expr
);
4017 Add_Association
(New_C
, New_Expr
, New_Assoc_List
);
4018 end Resolve_Aggr_Expr
;
4024 procedure Rewrite_Range
(Root_Type
: Entity_Id
; Rge
: Node_Id
) is
4025 procedure Rewrite_Bound
4028 Expr_Disc
: Node_Id
);
4029 -- Rewrite a bound of the range Bound, when it is equal to the
4030 -- non-stored discriminant Disc, into the stored discriminant
4037 procedure Rewrite_Bound
4040 Expr_Disc
: Node_Id
)
4043 if Nkind
(Bound
) = N_Identifier
4044 and then Entity
(Bound
) = Disc
4046 Rewrite
(Bound
, New_Copy_Tree
(Expr_Disc
));
4052 Low
, High
: Node_Id
;
4054 Expr_Disc
: Elmt_Id
;
4056 -- Start of processing for Rewrite_Range
4059 if Has_Discriminants
(Root_Type
)
4060 and then Nkind
(Rge
) = N_Range
4062 Low
:= Low_Bound
(Rge
);
4063 High
:= High_Bound
(Rge
);
4065 Disc
:= First_Discriminant
(Root_Type
);
4066 Expr_Disc
:= First_Elmt
(Stored_Constraint
(Etype
(N
)));
4067 while Present
(Disc
) loop
4068 Rewrite_Bound
(Low
, Disc
, Node
(Expr_Disc
));
4069 Rewrite_Bound
(High
, Disc
, Node
(Expr_Disc
));
4070 Next_Discriminant
(Disc
);
4071 Next_Elmt
(Expr_Disc
);
4078 Components
: constant Elist_Id
:= New_Elmt_List
;
4079 -- Components is the list of the record components whose value must be
4080 -- provided in the aggregate. This list does include discriminants.
4082 Component
: Entity_Id
;
4083 Component_Elmt
: Elmt_Id
;
4085 Positional_Expr
: Node_Id
;
4087 -- Start of processing for Resolve_Record_Aggregate
4090 -- A record aggregate is restricted in SPARK:
4092 -- Each named association can have only a single choice.
4093 -- OTHERS cannot be used.
4094 -- Positional and named associations cannot be mixed.
4096 if Present
(Component_Associations
(N
))
4097 and then Present
(First
(Component_Associations
(N
)))
4099 if Present
(Expressions
(N
)) then
4100 Check_SPARK_05_Restriction
4101 ("named association cannot follow positional one",
4102 First
(Choices
(First
(Component_Associations
(N
)))));
4109 Assoc
:= First
(Component_Associations
(N
));
4110 while Present
(Assoc
) loop
4111 if List_Length
(Choices
(Assoc
)) > 1 then
4112 Check_SPARK_05_Restriction
4113 ("component association in record aggregate must "
4114 & "contain a single choice", Assoc
);
4117 if Nkind
(First
(Choices
(Assoc
))) = N_Others_Choice
then
4118 Check_SPARK_05_Restriction
4119 ("record aggregate cannot contain OTHERS", Assoc
);
4122 Assoc
:= Next
(Assoc
);
4127 -- We may end up calling Duplicate_Subexpr on expressions that are
4128 -- attached to New_Assoc_List. For this reason we need to attach it
4129 -- to the tree by setting its parent pointer to N. This parent point
4130 -- will change in STEP 8 below.
4132 Set_Parent
(New_Assoc_List
, N
);
4134 -- STEP 1: abstract type and null record verification
4136 if Is_Abstract_Type
(Typ
) then
4137 Error_Msg_N
("type of aggregate cannot be abstract", N
);
4140 if No
(First_Entity
(Typ
)) and then Null_Record_Present
(N
) then
4144 elsif Present
(First_Entity
(Typ
))
4145 and then Null_Record_Present
(N
)
4146 and then not Is_Tagged_Type
(Typ
)
4148 Error_Msg_N
("record aggregate cannot be null", N
);
4151 -- If the type has no components, then the aggregate should either
4152 -- have "null record", or in Ada 2005 it could instead have a single
4153 -- component association given by "others => <>". For Ada 95 we flag an
4154 -- error at this point, but for Ada 2005 we proceed with checking the
4155 -- associations below, which will catch the case where it's not an
4156 -- aggregate with "others => <>". Note that the legality of a <>
4157 -- aggregate for a null record type was established by AI05-016.
4159 elsif No
(First_Entity
(Typ
))
4160 and then Ada_Version
< Ada_2005
4162 Error_Msg_N
("record aggregate must be null", N
);
4166 -- STEP 2: Verify aggregate structure
4170 Bad_Aggregate
: Boolean := False;
4171 Selector_Name
: Node_Id
;
4174 if Present
(Component_Associations
(N
)) then
4175 Assoc
:= First
(Component_Associations
(N
));
4180 while Present
(Assoc
) loop
4181 Selector_Name
:= First
(Choices
(Assoc
));
4182 while Present
(Selector_Name
) loop
4183 if Nkind
(Selector_Name
) = N_Identifier
then
4186 elsif Nkind
(Selector_Name
) = N_Others_Choice
then
4187 if Selector_Name
/= First
(Choices
(Assoc
))
4188 or else Present
(Next
(Selector_Name
))
4191 ("OTHERS must appear alone in a choice list",
4195 elsif Present
(Next
(Assoc
)) then
4197 ("OTHERS must appear last in an aggregate",
4201 -- (Ada 2005): If this is an association with a box,
4202 -- indicate that the association need not represent
4205 elsif Box_Present
(Assoc
) then
4212 ("selector name should be identifier or OTHERS",
4214 Bad_Aggregate
:= True;
4217 Next
(Selector_Name
);
4223 if Bad_Aggregate
then
4228 -- STEP 3: Find discriminant Values
4231 Discrim
: Entity_Id
;
4232 Missing_Discriminants
: Boolean := False;
4235 if Present
(Expressions
(N
)) then
4236 Positional_Expr
:= First
(Expressions
(N
));
4238 Positional_Expr
:= Empty
;
4241 -- AI05-0115: if the ancestor part is a subtype mark, the ancestor
4242 -- must not have unknown discriminants.
4244 if Is_Derived_Type
(Typ
)
4245 and then Has_Unknown_Discriminants
(Root_Type
(Typ
))
4246 and then Nkind
(N
) /= N_Extension_Aggregate
4249 ("aggregate not available for type& whose ancestor "
4250 & "has unknown discriminants ", N
, Typ
);
4253 if Has_Unknown_Discriminants
(Typ
)
4254 and then Present
(Underlying_Record_View
(Typ
))
4256 Discrim
:= First_Discriminant
(Underlying_Record_View
(Typ
));
4257 elsif Has_Discriminants
(Typ
) then
4258 Discrim
:= First_Discriminant
(Typ
);
4263 -- First find the discriminant values in the positional components
4265 while Present
(Discrim
) and then Present
(Positional_Expr
) loop
4266 if Discriminant_Present
(Discrim
) then
4267 Resolve_Aggr_Expr
(Positional_Expr
, Discrim
);
4269 -- Ada 2005 (AI-231)
4271 if Ada_Version
>= Ada_2005
4272 and then Known_Null
(Positional_Expr
)
4274 Check_Can_Never_Be_Null
(Discrim
, Positional_Expr
);
4277 Next
(Positional_Expr
);
4280 if Present
(Get_Value
(Discrim
, Component_Associations
(N
))) then
4282 ("more than one value supplied for discriminant&",
4286 Next_Discriminant
(Discrim
);
4289 -- Find remaining discriminant values if any among named components
4291 while Present
(Discrim
) loop
4292 Expr
:= Get_Value
(Discrim
, Component_Associations
(N
), True);
4294 if not Discriminant_Present
(Discrim
) then
4295 if Present
(Expr
) then
4297 ("more than one value supplied for discriminant &",
4301 elsif No
(Expr
) then
4303 ("no value supplied for discriminant &", N
, Discrim
);
4304 Missing_Discriminants
:= True;
4307 Resolve_Aggr_Expr
(Expr
, Discrim
);
4310 Next_Discriminant
(Discrim
);
4313 if Missing_Discriminants
then
4317 -- At this point and until the beginning of STEP 6, New_Assoc_List
4318 -- contains only the discriminants and their values.
4322 -- STEP 4: Set the Etype of the record aggregate
4324 -- ??? This code is pretty much a copy of Sem_Ch3.Build_Subtype. That
4325 -- routine should really be exported in sem_util or some such and used
4326 -- in sem_ch3 and here rather than have a copy of the code which is a
4327 -- maintenance nightmare.
4329 -- ??? Performance WARNING. The current implementation creates a new
4330 -- itype for all aggregates whose base type is discriminated. This means
4331 -- that for record aggregates nested inside an array aggregate we will
4332 -- create a new itype for each record aggregate if the array component
4333 -- type has discriminants. For large aggregates this may be a problem.
4334 -- What should be done in this case is to reuse itypes as much as
4337 if Has_Discriminants
(Typ
)
4338 or else (Has_Unknown_Discriminants
(Typ
)
4339 and then Present
(Underlying_Record_View
(Typ
)))
4341 Build_Constrained_Itype
: declare
4342 Constrs
: constant List_Id
:= New_List
;
4343 Loc
: constant Source_Ptr
:= Sloc
(N
);
4346 New_Assoc
: Node_Id
;
4347 Subtyp_Decl
: Node_Id
;
4350 New_Assoc
:= First
(New_Assoc_List
);
4351 while Present
(New_Assoc
) loop
4352 Append_To
(Constrs
, Duplicate_Subexpr
(Expression
(New_Assoc
)));
4356 if Has_Unknown_Discriminants
(Typ
)
4357 and then Present
(Underlying_Record_View
(Typ
))
4360 Make_Subtype_Indication
(Loc
,
4362 New_Occurrence_Of
(Underlying_Record_View
(Typ
), Loc
),
4364 Make_Index_Or_Discriminant_Constraint
(Loc
,
4365 Constraints
=> Constrs
));
4368 Make_Subtype_Indication
(Loc
,
4370 New_Occurrence_Of
(Base_Type
(Typ
), Loc
),
4372 Make_Index_Or_Discriminant_Constraint
(Loc
,
4373 Constraints
=> Constrs
));
4376 Def_Id
:= Create_Itype
(Ekind
(Typ
), N
);
4379 Make_Subtype_Declaration
(Loc
,
4380 Defining_Identifier
=> Def_Id
,
4381 Subtype_Indication
=> Indic
);
4382 Set_Parent
(Subtyp_Decl
, Parent
(N
));
4384 -- Itypes must be analyzed with checks off (see itypes.ads)
4386 Analyze
(Subtyp_Decl
, Suppress
=> All_Checks
);
4388 Set_Etype
(N
, Def_Id
);
4389 Check_Static_Discriminated_Subtype
4390 (Def_Id
, Expression
(First
(New_Assoc_List
)));
4391 end Build_Constrained_Itype
;
4397 -- STEP 5: Get remaining components according to discriminant values
4401 Errors_Found
: Boolean := False;
4402 Record_Def
: Node_Id
;
4403 Parent_Typ
: Entity_Id
;
4404 Parent_Typ_List
: Elist_Id
;
4405 Parent_Elmt
: Elmt_Id
;
4406 Root_Typ
: Entity_Id
;
4409 if Is_Derived_Type
(Typ
) and then Is_Tagged_Type
(Typ
) then
4410 Parent_Typ_List
:= New_Elmt_List
;
4412 -- If this is an extension aggregate, the component list must
4413 -- include all components that are not in the given ancestor type.
4414 -- Otherwise, the component list must include components of all
4415 -- ancestors, starting with the root.
4417 if Nkind
(N
) = N_Extension_Aggregate
then
4418 Root_Typ
:= Base_Type
(Etype
(Ancestor_Part
(N
)));
4421 -- AI05-0115: check legality of aggregate for type with a
4422 -- private ancestor.
4424 Root_Typ
:= Root_Type
(Typ
);
4425 if Has_Private_Ancestor
(Typ
) then
4427 Ancestor
: constant Entity_Id
:=
4428 Find_Private_Ancestor
(Typ
);
4429 Ancestor_Unit
: constant Entity_Id
:=
4431 (Get_Source_Unit
(Ancestor
));
4432 Parent_Unit
: constant Entity_Id
:=
4433 Cunit_Entity
(Get_Source_Unit
4434 (Base_Type
(Etype
(Ancestor
))));
4436 -- Check whether we are in a scope that has full view
4437 -- over the private ancestor and its parent. This can
4438 -- only happen if the derivation takes place in a child
4439 -- unit of the unit that declares the parent, and we are
4440 -- in the private part or body of that child unit, else
4441 -- the aggregate is illegal.
4443 if Is_Child_Unit
(Ancestor_Unit
)
4444 and then Scope
(Ancestor_Unit
) = Parent_Unit
4445 and then In_Open_Scopes
(Scope
(Ancestor
))
4447 (In_Private_Part
(Scope
(Ancestor
))
4448 or else In_Package_Body
(Scope
(Ancestor
)))
4454 ("type of aggregate has private ancestor&!",
4456 Error_Msg_N
("must use extension aggregate!", N
);
4462 Dnode
:= Declaration_Node
(Base_Type
(Root_Typ
));
4464 -- If we don't get a full declaration, then we have some error
4465 -- which will get signalled later so skip this part. Otherwise
4466 -- gather components of root that apply to the aggregate type.
4467 -- We use the base type in case there is an applicable stored
4468 -- constraint that renames the discriminants of the root.
4470 if Nkind
(Dnode
) = N_Full_Type_Declaration
then
4471 Record_Def
:= Type_Definition
(Dnode
);
4474 Component_List
(Record_Def
),
4475 Governed_By
=> New_Assoc_List
,
4477 Report_Errors
=> Errors_Found
);
4479 if Errors_Found
then
4481 ("discriminant controlling variant part is not static",
4488 Parent_Typ
:= Base_Type
(Typ
);
4489 while Parent_Typ
/= Root_Typ
loop
4490 Prepend_Elmt
(Parent_Typ
, To
=> Parent_Typ_List
);
4491 Parent_Typ
:= Etype
(Parent_Typ
);
4493 if Nkind
(Parent
(Base_Type
(Parent_Typ
))) =
4494 N_Private_Type_Declaration
4495 or else Nkind
(Parent
(Base_Type
(Parent_Typ
))) =
4496 N_Private_Extension_Declaration
4498 if Nkind
(N
) /= N_Extension_Aggregate
then
4500 ("type of aggregate has private ancestor&!",
4502 Error_Msg_N
("must use extension aggregate!", N
);
4505 elsif Parent_Typ
/= Root_Typ
then
4507 ("ancestor part of aggregate must be private type&",
4508 Ancestor_Part
(N
), Parent_Typ
);
4512 -- The current view of ancestor part may be a private type,
4513 -- while the context type is always non-private.
4515 elsif Is_Private_Type
(Root_Typ
)
4516 and then Present
(Full_View
(Root_Typ
))
4517 and then Nkind
(N
) = N_Extension_Aggregate
4519 exit when Base_Type
(Full_View
(Root_Typ
)) = Parent_Typ
;
4523 -- Now collect components from all other ancestors, beginning
4524 -- with the current type. If the type has unknown discriminants
4525 -- use the component list of the Underlying_Record_View, which
4526 -- needs to be used for the subsequent expansion of the aggregate
4527 -- into assignments.
4529 Parent_Elmt
:= First_Elmt
(Parent_Typ_List
);
4530 while Present
(Parent_Elmt
) loop
4531 Parent_Typ
:= Node
(Parent_Elmt
);
4533 if Has_Unknown_Discriminants
(Parent_Typ
)
4534 and then Present
(Underlying_Record_View
(Typ
))
4536 Parent_Typ
:= Underlying_Record_View
(Parent_Typ
);
4539 Record_Def
:= Type_Definition
(Parent
(Base_Type
(Parent_Typ
)));
4540 Gather_Components
(Empty
,
4541 Component_List
(Record_Extension_Part
(Record_Def
)),
4542 Governed_By
=> New_Assoc_List
,
4544 Report_Errors
=> Errors_Found
);
4546 Next_Elmt
(Parent_Elmt
);
4549 -- Typ is not a derived tagged type
4552 Record_Def
:= Type_Definition
(Parent
(Base_Type
(Typ
)));
4554 if Null_Present
(Record_Def
) then
4557 elsif not Has_Unknown_Discriminants
(Typ
) then
4560 Component_List
(Record_Def
),
4561 Governed_By
=> New_Assoc_List
,
4563 Report_Errors
=> Errors_Found
);
4567 (Base_Type
(Underlying_Record_View
(Typ
)),
4568 Component_List
(Record_Def
),
4569 Governed_By
=> New_Assoc_List
,
4571 Report_Errors
=> Errors_Found
);
4575 if Errors_Found
then
4580 -- STEP 6: Find component Values
4583 Component_Elmt
:= First_Elmt
(Components
);
4585 -- First scan the remaining positional associations in the aggregate.
4586 -- Remember that at this point Positional_Expr contains the current
4587 -- positional association if any is left after looking for discriminant
4588 -- values in step 3.
4590 while Present
(Positional_Expr
) and then Present
(Component_Elmt
) loop
4591 Component
:= Node
(Component_Elmt
);
4592 Resolve_Aggr_Expr
(Positional_Expr
, Component
);
4594 -- Ada 2005 (AI-231)
4596 if Ada_Version
>= Ada_2005
and then Known_Null
(Positional_Expr
) then
4597 Check_Can_Never_Be_Null
(Component
, Positional_Expr
);
4600 if Present
(Get_Value
(Component
, Component_Associations
(N
))) then
4602 ("more than one value supplied for Component &", N
, Component
);
4605 Next
(Positional_Expr
);
4606 Next_Elmt
(Component_Elmt
);
4609 if Present
(Positional_Expr
) then
4611 ("too many components for record aggregate", Positional_Expr
);
4614 -- Now scan for the named arguments of the aggregate
4616 while Present
(Component_Elmt
) loop
4617 Component
:= Node
(Component_Elmt
);
4618 Expr
:= Get_Value
(Component
, Component_Associations
(N
), True);
4620 -- Note: The previous call to Get_Value sets the value of the
4621 -- variable Is_Box_Present.
4623 -- Ada 2005 (AI-287): Handle components with default initialization.
4624 -- Note: This feature was originally added to Ada 2005 for limited
4625 -- but it was finally allowed with any type.
4627 if Is_Box_Present
then
4628 Check_Box_Component
: declare
4629 Ctyp
: constant Entity_Id
:= Etype
(Component
);
4632 -- If there is a default expression for the aggregate, copy
4633 -- it into a new association. This copy must modify the scopes
4634 -- of internal types that may be attached to the expression
4635 -- (e.g. index subtypes of arrays) because in general the type
4636 -- declaration and the aggregate appear in different scopes,
4637 -- and the backend requires the scope of the type to match the
4638 -- point at which it is elaborated.
4640 -- If the component has an initialization procedure (IP) we
4641 -- pass the component to the expander, which will generate
4642 -- the call to such IP.
4644 -- If the component has discriminants, their values must
4645 -- be taken from their subtype. This is indispensable for
4646 -- constraints that are given by the current instance of an
4647 -- enclosing type, to allow the expansion of the aggregate to
4648 -- replace the reference to the current instance by the target
4649 -- object of the aggregate.
4651 if Present
(Parent
(Component
))
4652 and then Nkind
(Parent
(Component
)) = N_Component_Declaration
4653 and then Present
(Expression
(Parent
(Component
)))
4656 New_Copy_Tree_And_Copy_Dimensions
4657 (Expression
(Parent
(Component
)),
4658 New_Scope
=> Current_Scope
,
4659 New_Sloc
=> Sloc
(N
));
4661 -- As the type of the copied default expression may refer
4662 -- to discriminants of the record type declaration, these
4663 -- non-stored discriminants need to be rewritten into stored
4664 -- discriminant values for the aggregate. This is required
4665 -- in GNATprove mode, and is adopted in all modes to avoid
4666 -- special-casing GNATprove mode.
4668 if Is_Array_Type
(Etype
(Expr
)) then
4670 Rec_Typ
: constant Entity_Id
:= Scope
(Component
);
4671 -- Root record type whose discriminants may be used as
4672 -- bounds in range nodes.
4677 -- Rewrite the range nodes occurring in the indexes
4680 Index
:= First_Index
(Etype
(Expr
));
4681 while Present
(Index
) loop
4682 Rewrite_Range
(Rec_Typ
, Index
);
4684 (Rec_Typ
, Scalar_Range
(Etype
(Index
)));
4689 -- Rewrite the range nodes occurring as aggregate
4692 if Nkind
(Expr
) = N_Aggregate
4693 and then Present
(Aggregate_Bounds
(Expr
))
4695 Rewrite_Range
(Rec_Typ
, Aggregate_Bounds
(Expr
));
4701 (Component
=> Component
,
4703 Assoc_List
=> New_Assoc_List
);
4704 Set_Has_Self_Reference
(N
);
4706 -- A box-defaulted access component gets the value null. Also
4707 -- included are components of private types whose underlying
4708 -- type is an access type. In either case set the type of the
4709 -- literal, for subsequent use in semantic checks.
4711 elsif Present
(Underlying_Type
(Ctyp
))
4712 and then Is_Access_Type
(Underlying_Type
(Ctyp
))
4714 -- If the component's type is private with an access type as
4715 -- its underlying type then we have to create an unchecked
4716 -- conversion to satisfy type checking.
4718 if Is_Private_Type
(Ctyp
) then
4720 Qual_Null
: constant Node_Id
:=
4721 Make_Qualified_Expression
(Sloc
(N
),
4724 (Underlying_Type
(Ctyp
), Sloc
(N
)),
4725 Expression
=> Make_Null
(Sloc
(N
)));
4727 Convert_Null
: constant Node_Id
:=
4728 Unchecked_Convert_To
4732 Analyze_And_Resolve
(Convert_Null
, Ctyp
);
4734 (Component
=> Component
,
4735 Expr
=> Convert_Null
,
4736 Assoc_List
=> New_Assoc_List
);
4739 -- Otherwise the component type is non-private
4742 Expr
:= Make_Null
(Sloc
(N
));
4743 Set_Etype
(Expr
, Ctyp
);
4746 (Component
=> Component
,
4748 Assoc_List
=> New_Assoc_List
);
4751 -- Ada 2012: If component is scalar with default value, use it
4753 elsif Is_Scalar_Type
(Ctyp
)
4754 and then Has_Default_Aspect
(Ctyp
)
4757 (Component
=> Component
,
4759 Default_Aspect_Value
4760 (First_Subtype
(Underlying_Type
(Ctyp
))),
4761 Assoc_List
=> New_Assoc_List
);
4763 elsif Has_Non_Null_Base_Init_Proc
(Ctyp
)
4764 or else not Expander_Active
4766 if Is_Record_Type
(Ctyp
)
4767 and then Has_Discriminants
(Ctyp
)
4768 and then not Is_Private_Type
(Ctyp
)
4770 -- We build a partially initialized aggregate with the
4771 -- values of the discriminants and box initialization
4772 -- for the rest, if other components are present.
4774 -- The type of the aggregate is the known subtype of
4775 -- the component. The capture of discriminants must be
4776 -- recursive because subcomponents may be constrained
4777 -- (transitively) by discriminants of enclosing types.
4778 -- For a private type with discriminants, a call to the
4779 -- initialization procedure will be generated, and no
4780 -- subaggregate is needed.
4782 Capture_Discriminants
: declare
4783 Loc
: constant Source_Ptr
:= Sloc
(N
);
4787 Expr
:= Make_Aggregate
(Loc
, New_List
, New_List
);
4788 Set_Etype
(Expr
, Ctyp
);
4790 -- If the enclosing type has discriminants, they have
4791 -- been collected in the aggregate earlier, and they
4792 -- may appear as constraints of subcomponents.
4794 -- Similarly if this component has discriminants, they
4795 -- might in turn be propagated to their components.
4797 if Has_Discriminants
(Typ
) then
4798 Add_Discriminant_Values
(Expr
, New_Assoc_List
);
4799 Propagate_Discriminants
(Expr
, New_Assoc_List
);
4801 elsif Has_Discriminants
(Ctyp
) then
4802 Add_Discriminant_Values
4803 (Expr
, Component_Associations
(Expr
));
4804 Propagate_Discriminants
4805 (Expr
, Component_Associations
(Expr
));
4812 -- If the type has additional components, create
4813 -- an OTHERS box association for them.
4815 Comp
:= First_Component
(Ctyp
);
4816 while Present
(Comp
) loop
4817 if Ekind
(Comp
) = E_Component
then
4818 if not Is_Record_Type
(Etype
(Comp
)) then
4820 (Component_Associations
(Expr
),
4821 Make_Component_Association
(Loc
,
4824 Make_Others_Choice
(Loc
)),
4825 Expression
=> Empty
,
4826 Box_Present
=> True));
4832 Next_Component
(Comp
);
4838 (Component
=> Component
,
4840 Assoc_List
=> New_Assoc_List
);
4841 end Capture_Discriminants
;
4843 -- Otherwise the component type is not a record, or it has
4844 -- not discriminants, or it is private.
4848 (Component
=> Component
,
4850 Assoc_List
=> New_Assoc_List
,
4851 Is_Box_Present
=> True);
4854 -- Otherwise we only need to resolve the expression if the
4855 -- component has partially initialized values (required to
4856 -- expand the corresponding assignments and run-time checks).
4858 elsif Present
(Expr
)
4859 and then Is_Partially_Initialized_Type
(Ctyp
)
4861 Resolve_Aggr_Expr
(Expr
, Component
);
4863 end Check_Box_Component
;
4865 elsif No
(Expr
) then
4867 -- Ignore hidden components associated with the position of the
4868 -- interface tags: these are initialized dynamically.
4870 if not Present
(Related_Type
(Component
)) then
4872 ("no value supplied for component &!", N
, Component
);
4876 Resolve_Aggr_Expr
(Expr
, Component
);
4879 Next_Elmt
(Component_Elmt
);
4882 -- STEP 7: check for invalid components + check type in choice list
4886 New_Assoc
: Node_Id
;
4892 -- Type of first component in choice list
4895 if Present
(Component_Associations
(N
)) then
4896 Assoc
:= First
(Component_Associations
(N
));
4901 Verification
: while Present
(Assoc
) loop
4902 Selectr
:= First
(Choices
(Assoc
));
4905 if Nkind
(Selectr
) = N_Others_Choice
then
4907 -- Ada 2005 (AI-287): others choice may have expression or box
4909 if No
(Others_Etype
) and then Others_Box
= 0 then
4911 ("OTHERS must represent at least one component", Selectr
);
4913 elsif Others_Box
= 1 and then Warn_On_Redundant_Constructs
then
4914 Error_Msg_N
("others choice is redundant?", Box_Node
);
4916 ("\previous choices cover all components?", Box_Node
);
4922 while Present
(Selectr
) loop
4923 New_Assoc
:= First
(New_Assoc_List
);
4924 while Present
(New_Assoc
) loop
4925 Component
:= First
(Choices
(New_Assoc
));
4927 if Chars
(Selectr
) = Chars
(Component
) then
4929 Check_Identifier
(Selectr
, Entity
(Component
));
4938 -- If no association, this is not a legal component of the type
4939 -- in question, unless its association is provided with a box.
4941 if No
(New_Assoc
) then
4942 if Box_Present
(Parent
(Selectr
)) then
4944 -- This may still be a bogus component with a box. Scan
4945 -- list of components to verify that a component with
4946 -- that name exists.
4952 C
:= First_Component
(Typ
);
4953 while Present
(C
) loop
4954 if Chars
(C
) = Chars
(Selectr
) then
4956 -- If the context is an extension aggregate,
4957 -- the component must not be inherited from
4958 -- the ancestor part of the aggregate.
4960 if Nkind
(N
) /= N_Extension_Aggregate
4962 Scope
(Original_Record_Component
(C
)) /=
4963 Etype
(Ancestor_Part
(N
))
4973 Error_Msg_Node_2
:= Typ
;
4974 Error_Msg_N
("& is not a component of}", Selectr
);
4978 elsif Chars
(Selectr
) /= Name_uTag
4979 and then Chars
(Selectr
) /= Name_uParent
4981 if not Has_Discriminants
(Typ
) then
4982 Error_Msg_Node_2
:= Typ
;
4983 Error_Msg_N
("& is not a component of}", Selectr
);
4986 ("& is not a component of the aggregate subtype",
4990 Check_Misspelled_Component
(Components
, Selectr
);
4993 elsif No
(Typech
) then
4994 Typech
:= Base_Type
(Etype
(Component
));
4996 -- AI05-0199: In Ada 2012, several components of anonymous
4997 -- access types can appear in a choice list, as long as the
4998 -- designated types match.
5000 elsif Typech
/= Base_Type
(Etype
(Component
)) then
5001 if Ada_Version
>= Ada_2012
5002 and then Ekind
(Typech
) = E_Anonymous_Access_Type
5004 Ekind
(Etype
(Component
)) = E_Anonymous_Access_Type
5005 and then Base_Type
(Designated_Type
(Typech
)) =
5006 Base_Type
(Designated_Type
(Etype
(Component
)))
5008 Subtypes_Statically_Match
(Typech
, (Etype
(Component
)))
5012 elsif not Box_Present
(Parent
(Selectr
)) then
5014 ("components in choice list must have same type",
5023 end loop Verification
;
5026 -- STEP 8: replace the original aggregate
5029 New_Aggregate
: constant Node_Id
:= New_Copy
(N
);
5032 Set_Expressions
(New_Aggregate
, No_List
);
5033 Set_Etype
(New_Aggregate
, Etype
(N
));
5034 Set_Component_Associations
(New_Aggregate
, New_Assoc_List
);
5035 Set_Check_Actuals
(New_Aggregate
, Check_Actuals
(N
));
5037 Rewrite
(N
, New_Aggregate
);
5040 -- Check the dimensions of the components in the record aggregate
5042 Analyze_Dimension_Extension_Or_Record_Aggregate
(N
);
5043 end Resolve_Record_Aggregate
;
5045 -----------------------------
5046 -- Check_Can_Never_Be_Null --
5047 -----------------------------
5049 procedure Check_Can_Never_Be_Null
(Typ
: Entity_Id
; Expr
: Node_Id
) is
5050 Comp_Typ
: Entity_Id
;
5054 (Ada_Version
>= Ada_2005
5055 and then Present
(Expr
)
5056 and then Known_Null
(Expr
));
5059 when E_Array_Type
=>
5060 Comp_Typ
:= Component_Type
(Typ
);
5065 Comp_Typ
:= Etype
(Typ
);
5071 if Can_Never_Be_Null
(Comp_Typ
) then
5073 -- Here we know we have a constraint error. Note that we do not use
5074 -- Apply_Compile_Time_Constraint_Error here to the Expr, which might
5075 -- seem the more natural approach. That's because in some cases the
5076 -- components are rewritten, and the replacement would be missed.
5077 -- We do not mark the whole aggregate as raising a constraint error,
5078 -- because the association may be a null array range.
5081 ("(Ada 2005) null not allowed in null-excluding component??", Expr
);
5083 ("\Constraint_Error will be raised at run time??", Expr
);
5086 Make_Raise_Constraint_Error
5087 (Sloc
(Expr
), Reason
=> CE_Access_Check_Failed
));
5088 Set_Etype
(Expr
, Comp_Typ
);
5089 Set_Analyzed
(Expr
);
5091 end Check_Can_Never_Be_Null
;
5093 ---------------------
5094 -- Sort_Case_Table --
5095 ---------------------
5097 procedure Sort_Case_Table
(Case_Table
: in out Case_Table_Type
) is
5098 U
: constant Int
:= Case_Table
'Last;
5106 T
:= Case_Table
(K
+ 1);
5110 and then Expr_Value
(Case_Table
(J
- 1).Lo
) > Expr_Value
(T
.Lo
)
5112 Case_Table
(J
) := Case_Table
(J
- 1);
5116 Case_Table
(J
) := T
;
5119 end Sort_Case_Table
;