1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2015, 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 Ada
.Characters
.Latin_1
; use Ada
.Characters
.Latin_1
;
28 with Atree
; use Atree
;
29 with Casing
; use Casing
;
30 with Checks
; use Checks
;
31 with Debug
; use Debug
;
32 with Einfo
; use Einfo
;
33 with Elists
; use Elists
;
34 with Errout
; use Errout
;
36 with Exp_Dist
; use Exp_Dist
;
37 with Exp_Util
; use Exp_Util
;
38 with Expander
; use Expander
;
39 with Freeze
; use Freeze
;
40 with Gnatvsn
; use Gnatvsn
;
41 with Itypes
; use Itypes
;
43 with Lib
.Xref
; use Lib
.Xref
;
44 with Nlists
; use Nlists
;
45 with Nmake
; use Nmake
;
47 with Restrict
; use Restrict
;
48 with Rident
; use Rident
;
49 with Rtsfind
; use Rtsfind
;
50 with Sdefault
; use Sdefault
;
52 with Sem_Aux
; use Sem_Aux
;
53 with Sem_Cat
; use Sem_Cat
;
54 with Sem_Ch6
; use Sem_Ch6
;
55 with Sem_Ch8
; use Sem_Ch8
;
56 with Sem_Ch10
; use Sem_Ch10
;
57 with Sem_Dim
; use Sem_Dim
;
58 with Sem_Dist
; use Sem_Dist
;
59 with Sem_Elab
; use Sem_Elab
;
60 with Sem_Elim
; use Sem_Elim
;
61 with Sem_Eval
; use Sem_Eval
;
62 with Sem_Prag
; use Sem_Prag
;
63 with Sem_Res
; use Sem_Res
;
64 with Sem_Type
; use Sem_Type
;
65 with Sem_Util
; use Sem_Util
;
67 with Stand
; use Stand
;
68 with Sinfo
; use Sinfo
;
69 with Sinput
; use Sinput
;
71 with Stringt
; use Stringt
;
73 with Stylesw
; use Stylesw
;
74 with Targparm
; use Targparm
;
75 with Ttypes
; use Ttypes
;
76 with Tbuild
; use Tbuild
;
77 with Uintp
; use Uintp
;
78 with Uname
; use Uname
;
79 with Urealp
; use Urealp
;
81 package body Sem_Attr
is
83 True_Value
: constant Uint
:= Uint_1
;
84 False_Value
: constant Uint
:= Uint_0
;
85 -- Synonyms to be used when these constants are used as Boolean values
87 Bad_Attribute
: exception;
88 -- Exception raised if an error is detected during attribute processing,
89 -- used so that we can abandon the processing so we don't run into
90 -- trouble with cascaded errors.
92 -- The following array is the list of attributes defined in the Ada 83 RM.
93 -- In Ada 83 mode, these are the only recognized attributes. In other Ada
94 -- modes all these attributes are recognized, even if removed in Ada 95.
96 Attribute_83
: constant Attribute_Class_Array
:= Attribute_Class_Array
'(
102 Attribute_Constrained |
109 Attribute_First_Bit |
115 Attribute_Leading_Part |
117 Attribute_Machine_Emax |
118 Attribute_Machine_Emin |
119 Attribute_Machine_Mantissa |
120 Attribute_Machine_Overflows |
121 Attribute_Machine_Radix |
122 Attribute_Machine_Rounds |
128 Attribute_Safe_Emax |
129 Attribute_Safe_Large |
130 Attribute_Safe_Small |
133 Attribute_Storage_Size |
135 Attribute_Terminated |
138 Attribute_Width => True,
141 -- The following array is the list of attributes defined in the Ada 2005
142 -- RM which are not defined in Ada 95. These are recognized in Ada 95 mode,
143 -- but in Ada 95 they are considered to be implementation defined.
145 Attribute_05 : constant Attribute_Class_Array := Attribute_Class_Array'(
146 Attribute_Machine_Rounding |
149 Attribute_Stream_Size |
150 Attribute_Wide_Wide_Width
=> True,
153 -- The following array is the list of attributes defined in the Ada 2012
154 -- RM which are not defined in Ada 2005. These are recognized in Ada 95
155 -- and Ada 2005 modes, but are considered to be implementation defined.
157 Attribute_12
: constant Attribute_Class_Array
:= Attribute_Class_Array
'(
158 Attribute_First_Valid |
159 Attribute_Has_Same_Storage |
160 Attribute_Last_Valid |
161 Attribute_Max_Alignment_For_Allocation => True,
164 -- The following array contains all attributes that imply a modification
165 -- of their prefixes or result in an access value. Such prefixes can be
166 -- considered as lvalues.
168 Attribute_Name_Implies_Lvalue_Prefix : constant Attribute_Class_Array :=
169 Attribute_Class_Array'(
174 Attribute_Unchecked_Access |
175 Attribute_Unrestricted_Access
=> True,
178 -----------------------
179 -- Local_Subprograms --
180 -----------------------
182 procedure Eval_Attribute
(N
: Node_Id
);
183 -- Performs compile time evaluation of attributes where possible, leaving
184 -- the Is_Static_Expression/Raises_Constraint_Error flags appropriately
185 -- set, and replacing the node with a literal node if the value can be
186 -- computed at compile time. All static attribute references are folded,
187 -- as well as a number of cases of non-static attributes that can always
188 -- be computed at compile time (e.g. floating-point model attributes that
189 -- are applied to non-static subtypes). Of course in such cases, the
190 -- Is_Static_Expression flag will not be set on the resulting literal.
191 -- Note that the only required action of this procedure is to catch the
192 -- static expression cases as described in the RM. Folding of other cases
193 -- is done where convenient, but some additional non-static folding is in
194 -- Expand_N_Attribute_Reference in cases where this is more convenient.
196 function Is_Anonymous_Tagged_Base
198 Typ
: Entity_Id
) return Boolean;
199 -- For derived tagged types that constrain parent discriminants we build
200 -- an anonymous unconstrained base type. We need to recognize the relation
201 -- between the two when analyzing an access attribute for a constrained
202 -- component, before the full declaration for Typ has been analyzed, and
203 -- where therefore the prefix of the attribute does not match the enclosing
206 procedure Set_Boolean_Result
(N
: Node_Id
; B
: Boolean);
207 -- Rewrites node N with an occurrence of either Standard_False or
208 -- Standard_True, depending on the value of the parameter B. The
209 -- result is marked as a static expression.
211 -----------------------
212 -- Analyze_Attribute --
213 -----------------------
215 procedure Analyze_Attribute
(N
: Node_Id
) is
216 Loc
: constant Source_Ptr
:= Sloc
(N
);
217 Aname
: constant Name_Id
:= Attribute_Name
(N
);
218 P
: constant Node_Id
:= Prefix
(N
);
219 Exprs
: constant List_Id
:= Expressions
(N
);
220 Attr_Id
: constant Attribute_Id
:= Get_Attribute_Id
(Aname
);
225 -- Type of prefix after analysis
227 P_Base_Type
: Entity_Id
;
228 -- Base type of prefix after analysis
230 -----------------------
231 -- Local Subprograms --
232 -----------------------
234 procedure Address_Checks
;
235 -- Semantic checks for valid use of Address attribute. This was made
236 -- a separate routine with the idea of using it for unrestricted access
237 -- which seems like it should follow the same rules, but that turned
238 -- out to be impractical. So now this is only used for Address.
240 procedure Analyze_Access_Attribute
;
241 -- Used for Access, Unchecked_Access, Unrestricted_Access attributes.
242 -- Internally, Id distinguishes which of the three cases is involved.
244 procedure Analyze_Attribute_Old_Result
245 (Legal
: out Boolean;
246 Spec_Id
: out Entity_Id
);
247 -- Common processing for attributes 'Old and 'Result. The routine checks
248 -- that the attribute appears in a postcondition-like aspect or pragma
249 -- associated with a suitable subprogram or a body. Flag Legal is set
250 -- when the above criteria are met. Spec_Id denotes the entity of the
251 -- subprogram [body] or Empty if the attribute is illegal.
253 procedure Bad_Attribute_For_Predicate
;
254 -- Output error message for use of a predicate (First, Last, Range) not
255 -- allowed with a type that has predicates. If the type is a generic
256 -- actual, then the message is a warning, and we generate code to raise
257 -- program error with an appropriate reason. No error message is given
258 -- for internally generated uses of the attributes. This legality rule
259 -- only applies to scalar types.
261 procedure Check_Array_Or_Scalar_Type
;
262 -- Common procedure used by First, Last, Range attribute to check
263 -- that the prefix is a constrained array or scalar type, or a name
264 -- of an array object, and that an argument appears only if appropriate
265 -- (i.e. only in the array case).
267 procedure Check_Array_Type
;
268 -- Common semantic checks for all array attributes. Checks that the
269 -- prefix is a constrained array type or the name of an array object.
270 -- The error message for non-arrays is specialized appropriately.
272 procedure Check_Asm_Attribute
;
273 -- Common semantic checks for Asm_Input and Asm_Output attributes
275 procedure Check_Component
;
276 -- Common processing for Bit_Position, First_Bit, Last_Bit, and
277 -- Position. Checks prefix is an appropriate selected component.
279 procedure Check_Decimal_Fixed_Point_Type
;
280 -- Check that prefix of attribute N is a decimal fixed-point type
282 procedure Check_Dereference
;
283 -- If the prefix of attribute is an object of an access type, then
284 -- introduce an explicit dereference, and adjust P_Type accordingly.
286 procedure Check_Discrete_Type
;
287 -- Verify that prefix of attribute N is a discrete type
290 -- Check that no attribute arguments are present
292 procedure Check_Either_E0_Or_E1
;
293 -- Check that there are zero or one attribute arguments present
296 -- Check that exactly one attribute argument is present
299 -- Check that two attribute arguments are present
301 procedure Check_Enum_Image
;
302 -- If the prefix type of 'Image is an enumeration type, set all its
303 -- literals as referenced, since the image function could possibly end
304 -- up referencing any of the literals indirectly. Same for Enum_Val.
305 -- Set the flag only if the reference is in the main code unit. Same
306 -- restriction when resolving 'Value; otherwise an improperly set
307 -- reference when analyzing an inlined body will lose a proper
308 -- warning on a useless with_clause.
310 procedure Check_First_Last_Valid
;
311 -- Perform all checks for First_Valid and Last_Valid attributes
313 procedure Check_Fixed_Point_Type
;
314 -- Verify that prefix of attribute N is a fixed type
316 procedure Check_Fixed_Point_Type_0
;
317 -- Verify that prefix of attribute N is a fixed type and that
318 -- no attribute expressions are present
320 procedure Check_Floating_Point_Type
;
321 -- Verify that prefix of attribute N is a float type
323 procedure Check_Floating_Point_Type_0
;
324 -- Verify that prefix of attribute N is a float type and that
325 -- no attribute expressions are present
327 procedure Check_Floating_Point_Type_1
;
328 -- Verify that prefix of attribute N is a float type and that
329 -- exactly one attribute expression is present
331 procedure Check_Floating_Point_Type_2
;
332 -- Verify that prefix of attribute N is a float type and that
333 -- two attribute expressions are present
335 procedure Check_SPARK_05_Restriction_On_Attribute
;
336 -- Issue an error in formal mode because attribute N is allowed
338 procedure Check_Integer_Type
;
339 -- Verify that prefix of attribute N is an integer type
341 procedure Check_Modular_Integer_Type
;
342 -- Verify that prefix of attribute N is a modular integer type
344 procedure Check_Not_CPP_Type
;
345 -- Check that P (the prefix of the attribute) is not an CPP type
346 -- for which no Ada predefined primitive is available.
348 procedure Check_Not_Incomplete_Type
;
349 -- Check that P (the prefix of the attribute) is not an incomplete
350 -- type or a private type for which no full view has been given.
352 procedure Check_Object_Reference
(P
: Node_Id
);
353 -- Check that P is an object reference
355 procedure Check_PolyORB_Attribute
;
356 -- Validity checking for PolyORB/DSA attribute
358 procedure Check_Program_Unit
;
359 -- Verify that prefix of attribute N is a program unit
361 procedure Check_Real_Type
;
362 -- Verify that prefix of attribute N is fixed or float type
364 procedure Check_Scalar_Type
;
365 -- Verify that prefix of attribute N is a scalar type
367 procedure Check_Standard_Prefix
;
368 -- Verify that prefix of attribute N is package Standard. Also checks
369 -- that there are no arguments.
371 procedure Check_Stream_Attribute
(Nam
: TSS_Name_Type
);
372 -- Validity checking for stream attribute. Nam is the TSS name of the
373 -- corresponding possible defined attribute function (e.g. for the
374 -- Read attribute, Nam will be TSS_Stream_Read).
376 procedure Check_System_Prefix
;
377 -- Verify that prefix of attribute N is package System
379 procedure Check_Task_Prefix
;
380 -- Verify that prefix of attribute N is a task or task type
382 procedure Check_Type
;
383 -- Verify that the prefix of attribute N is a type
385 procedure Check_Unit_Name
(Nod
: Node_Id
);
386 -- Check that Nod is of the form of a library unit name, i.e that
387 -- it is an identifier, or a selected component whose prefix is
388 -- itself of the form of a library unit name. Note that this is
389 -- quite different from Check_Program_Unit, since it only checks
390 -- the syntactic form of the name, not the semantic identity. This
391 -- is because it is used with attributes (Elab_Body, Elab_Spec,
392 -- UET_Address and Elaborated) which can refer to non-visible unit.
394 procedure Error_Attr
(Msg
: String; Error_Node
: Node_Id
);
395 pragma No_Return
(Error_Attr
);
396 procedure Error_Attr
;
397 pragma No_Return
(Error_Attr
);
398 -- Posts error using Error_Msg_N at given node, sets type of attribute
399 -- node to Any_Type, and then raises Bad_Attribute to avoid any further
400 -- semantic processing. The message typically contains a % insertion
401 -- character which is replaced by the attribute name. The call with
402 -- no arguments is used when the caller has already generated the
403 -- required error messages.
405 procedure Error_Attr_P
(Msg
: String);
406 pragma No_Return
(Error_Attr
);
407 -- Like Error_Attr, but error is posted at the start of the prefix
409 procedure Legal_Formal_Attribute
;
410 -- Common processing for attributes Definite and Has_Discriminants.
411 -- Checks that prefix is generic indefinite formal type.
413 procedure Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
;
414 -- Common processing for attributes Max_Alignment_For_Allocation and
415 -- Max_Size_In_Storage_Elements.
418 -- Common processing for attributes Max and Min
420 procedure Standard_Attribute
(Val
: Int
);
421 -- Used to process attributes whose prefix is package Standard which
422 -- yield values of type Universal_Integer. The attribute reference
423 -- node is rewritten with an integer literal of the given value which
424 -- is marked as static.
426 procedure Uneval_Old_Msg
;
427 -- Called when Loop_Entry or Old is used in a potentially unevaluated
428 -- expression. Generates appropriate message or warning depending on
429 -- the setting of Opt.Uneval_Old (or flags in an N_Aspect_Specification
430 -- node in the aspect case).
432 procedure Unexpected_Argument
(En
: Node_Id
);
433 -- Signal unexpected attribute argument (En is the argument)
435 procedure Validate_Non_Static_Attribute_Function_Call
;
436 -- Called when processing an attribute that is a function call to a
437 -- non-static function, i.e. an attribute function that either takes
438 -- non-scalar arguments or returns a non-scalar result. Verifies that
439 -- such a call does not appear in a preelaborable context.
445 procedure Address_Checks
is
447 -- An Address attribute created by expansion is legal even when it
448 -- applies to other entity-denoting expressions.
450 if not Comes_From_Source
(N
) then
453 -- Address attribute on a protected object self reference is legal
455 elsif Is_Protected_Self_Reference
(P
) then
458 -- Address applied to an entity
460 elsif Is_Entity_Name
(P
) then
462 Ent
: constant Entity_Id
:= Entity
(P
);
465 if Is_Subprogram
(Ent
) then
466 Set_Address_Taken
(Ent
);
467 Kill_Current_Values
(Ent
);
469 -- An Address attribute is accepted when generated by the
470 -- compiler for dispatching operation, and an error is
471 -- issued once the subprogram is frozen (to avoid confusing
472 -- errors about implicit uses of Address in the dispatch
473 -- table initialization).
475 if Has_Pragma_Inline_Always
(Entity
(P
))
476 and then Comes_From_Source
(P
)
479 ("prefix of % attribute cannot be Inline_Always "
482 -- It is illegal to apply 'Address to an intrinsic
483 -- subprogram. This is now formalized in AI05-0095.
484 -- In an instance, an attempt to obtain 'Address of an
485 -- intrinsic subprogram (e.g the renaming of a predefined
486 -- operator that is an actual) raises Program_Error.
488 elsif Convention
(Ent
) = Convention_Intrinsic
then
491 Make_Raise_Program_Error
(Loc
,
492 Reason
=> PE_Address_Of_Intrinsic
));
495 Error_Msg_Name_1
:= Aname
;
497 ("cannot take % of intrinsic subprogram", N
);
500 -- Issue an error if prefix denotes an eliminated subprogram
503 Check_For_Eliminated_Subprogram
(P
, Ent
);
506 -- Object or label reference
508 elsif Is_Object
(Ent
) or else Ekind
(Ent
) = E_Label
then
509 Set_Address_Taken
(Ent
);
511 -- Deal with No_Implicit_Aliasing restriction
513 if Restriction_Check_Required
(No_Implicit_Aliasing
) then
514 if not Is_Aliased_View
(P
) then
515 Check_Restriction
(No_Implicit_Aliasing
, P
);
517 Check_No_Implicit_Aliasing
(P
);
521 -- If we have an address of an object, and the attribute
522 -- comes from source, then set the object as potentially
523 -- source modified. We do this because the resulting address
524 -- can potentially be used to modify the variable and we
525 -- might not detect this, leading to some junk warnings.
527 Set_Never_Set_In_Source
(Ent
, False);
529 -- Allow Address to be applied to task or protected type,
530 -- returning null address (what is that about???)
532 elsif (Is_Concurrent_Type
(Etype
(Ent
))
533 and then Etype
(Ent
) = Base_Type
(Ent
))
534 or else Ekind
(Ent
) = E_Package
535 or else Is_Generic_Unit
(Ent
)
538 New_Occurrence_Of
(RTE
(RE_Null_Address
), Sloc
(N
)));
540 -- Anything else is illegal
543 Error_Attr
("invalid prefix for % attribute", P
);
549 elsif Is_Object_Reference
(P
) then
552 -- Subprogram called using dot notation
554 elsif Nkind
(P
) = N_Selected_Component
555 and then Is_Subprogram
(Entity
(Selector_Name
(P
)))
559 -- What exactly are we allowing here ??? and is this properly
560 -- documented in the sinfo documentation for this node ???
562 elsif Relaxed_RM_Semantics
563 and then Nkind
(P
) = N_Attribute_Reference
567 -- All other non-entity name cases are illegal
570 Error_Attr
("invalid prefix for % attribute", P
);
574 ------------------------------
575 -- Analyze_Access_Attribute --
576 ------------------------------
578 procedure Analyze_Access_Attribute
is
579 Acc_Type
: Entity_Id
;
584 function Build_Access_Object_Type
(DT
: Entity_Id
) return Entity_Id
;
585 -- Build an access-to-object type whose designated type is DT,
586 -- and whose Ekind is appropriate to the attribute type. The
587 -- type that is constructed is returned as the result.
589 procedure Build_Access_Subprogram_Type
(P
: Node_Id
);
590 -- Build an access to subprogram whose designated type is the type of
591 -- the prefix. If prefix is overloaded, so is the node itself. The
592 -- result is stored in Acc_Type.
594 function OK_Self_Reference
return Boolean;
595 -- An access reference whose prefix is a type can legally appear
596 -- within an aggregate, where it is obtained by expansion of
597 -- a defaulted aggregate. The enclosing aggregate that contains
598 -- the self-referenced is flagged so that the self-reference can
599 -- be expanded into a reference to the target object (see exp_aggr).
601 ------------------------------
602 -- Build_Access_Object_Type --
603 ------------------------------
605 function Build_Access_Object_Type
(DT
: Entity_Id
) return Entity_Id
is
606 Typ
: constant Entity_Id
:=
608 (E_Access_Attribute_Type
, Current_Scope
, Loc
, 'A');
610 Set_Etype
(Typ
, Typ
);
612 Set_Associated_Node_For_Itype
(Typ
, N
);
613 Set_Directly_Designated_Type
(Typ
, DT
);
615 end Build_Access_Object_Type
;
617 ----------------------------------
618 -- Build_Access_Subprogram_Type --
619 ----------------------------------
621 procedure Build_Access_Subprogram_Type
(P
: Node_Id
) is
622 Index
: Interp_Index
;
625 procedure Check_Local_Access
(E
: Entity_Id
);
626 -- Deal with possible access to local subprogram. If we have such
627 -- an access, we set a flag to kill all tracked values on any call
628 -- because this access value may be passed around, and any called
629 -- code might use it to access a local procedure which clobbers a
630 -- tracked value. If the scope is a loop or block, indicate that
631 -- value tracking is disabled for the enclosing subprogram.
633 function Get_Kind
(E
: Entity_Id
) return Entity_Kind
;
634 -- Distinguish between access to regular/protected subprograms
636 ------------------------
637 -- Check_Local_Access --
638 ------------------------
640 procedure Check_Local_Access
(E
: Entity_Id
) is
642 if not Is_Library_Level_Entity
(E
) then
643 Set_Suppress_Value_Tracking_On_Call
(Current_Scope
);
644 Set_Suppress_Value_Tracking_On_Call
645 (Nearest_Dynamic_Scope
(Current_Scope
));
647 end Check_Local_Access
;
653 function Get_Kind
(E
: Entity_Id
) return Entity_Kind
is
655 if Convention
(E
) = Convention_Protected
then
656 return E_Access_Protected_Subprogram_Type
;
658 return E_Access_Subprogram_Type
;
662 -- Start of processing for Build_Access_Subprogram_Type
665 -- In the case of an access to subprogram, use the name of the
666 -- subprogram itself as the designated type. Type-checking in
667 -- this case compares the signatures of the designated types.
669 -- Note: This fragment of the tree is temporarily malformed
670 -- because the correct tree requires an E_Subprogram_Type entity
671 -- as the designated type. In most cases this designated type is
672 -- later overridden by the semantics with the type imposed by the
673 -- context during the resolution phase. In the specific case of
674 -- the expression Address!(Prim'Unrestricted_Access), used to
675 -- initialize slots of dispatch tables, this work will be done by
676 -- the expander (see Exp_Aggr).
678 -- The reason to temporarily add this kind of node to the tree
679 -- instead of a proper E_Subprogram_Type itype, is the following:
680 -- in case of errors found in the source file we report better
681 -- error messages. For example, instead of generating the
684 -- "expected access to subprogram with profile
685 -- defined at line X"
687 -- we currently generate:
689 -- "expected access to function Z defined at line X"
691 Set_Etype
(N
, Any_Type
);
693 if not Is_Overloaded
(P
) then
694 Check_Local_Access
(Entity
(P
));
696 if not Is_Intrinsic_Subprogram
(Entity
(P
)) then
697 Acc_Type
:= Create_Itype
(Get_Kind
(Entity
(P
)), N
);
698 Set_Is_Public
(Acc_Type
, False);
699 Set_Etype
(Acc_Type
, Acc_Type
);
700 Set_Convention
(Acc_Type
, Convention
(Entity
(P
)));
701 Set_Directly_Designated_Type
(Acc_Type
, Entity
(P
));
702 Set_Etype
(N
, Acc_Type
);
703 Freeze_Before
(N
, Acc_Type
);
707 Get_First_Interp
(P
, Index
, It
);
708 while Present
(It
.Nam
) loop
709 Check_Local_Access
(It
.Nam
);
711 if not Is_Intrinsic_Subprogram
(It
.Nam
) then
712 Acc_Type
:= Create_Itype
(Get_Kind
(It
.Nam
), N
);
713 Set_Is_Public
(Acc_Type
, False);
714 Set_Etype
(Acc_Type
, Acc_Type
);
715 Set_Convention
(Acc_Type
, Convention
(It
.Nam
));
716 Set_Directly_Designated_Type
(Acc_Type
, It
.Nam
);
717 Add_One_Interp
(N
, Acc_Type
, Acc_Type
);
718 Freeze_Before
(N
, Acc_Type
);
721 Get_Next_Interp
(Index
, It
);
725 -- Cannot be applied to intrinsic. Looking at the tests above,
726 -- the only way Etype (N) can still be set to Any_Type is if
727 -- Is_Intrinsic_Subprogram was True for some referenced entity.
729 if Etype
(N
) = Any_Type
then
730 Error_Attr_P
("prefix of % attribute cannot be intrinsic");
732 end Build_Access_Subprogram_Type
;
734 ----------------------
735 -- OK_Self_Reference --
736 ----------------------
738 function OK_Self_Reference
return Boolean is
745 (Nkind
(Par
) = N_Component_Association
746 or else Nkind
(Par
) in N_Subexpr
)
748 if Nkind_In
(Par
, N_Aggregate
, N_Extension_Aggregate
) then
749 if Etype
(Par
) = Typ
then
750 Set_Has_Self_Reference
(Par
);
758 -- No enclosing aggregate, or not a self-reference
761 end OK_Self_Reference
;
763 -- Start of processing for Analyze_Access_Attribute
766 Check_SPARK_05_Restriction_On_Attribute
;
769 if Nkind
(P
) = N_Character_Literal
then
771 ("prefix of % attribute cannot be enumeration literal");
774 -- Case of access to subprogram
776 if Is_Entity_Name
(P
) and then Is_Overloadable
(Entity
(P
)) then
777 if Has_Pragma_Inline_Always
(Entity
(P
)) then
779 ("prefix of % attribute cannot be Inline_Always subprogram");
781 elsif Aname
= Name_Unchecked_Access
then
782 Error_Attr
("attribute% cannot be applied to a subprogram", P
);
785 -- Issue an error if the prefix denotes an eliminated subprogram
787 Check_For_Eliminated_Subprogram
(P
, Entity
(P
));
789 -- Check for obsolescent subprogram reference
791 Check_Obsolescent_2005_Entity
(Entity
(P
), P
);
793 -- Build the appropriate subprogram type
795 Build_Access_Subprogram_Type
(P
);
797 -- For P'Access or P'Unrestricted_Access, where P is a nested
798 -- subprogram, we might be passing P to another subprogram (but we
799 -- don't check that here), which might call P. P could modify
800 -- local variables, so we need to kill current values. It is
801 -- important not to do this for library-level subprograms, because
802 -- Kill_Current_Values is very inefficient in the case of library
803 -- level packages with lots of tagged types.
805 if Is_Library_Level_Entity
(Entity
(Prefix
(N
))) then
808 -- Do not kill values on nodes initializing dispatch tables
809 -- slots. The construct Prim_Ptr!(Prim'Unrestricted_Access)
810 -- is currently generated by the expander only for this
811 -- purpose. Done to keep the quality of warnings currently
812 -- generated by the compiler (otherwise any declaration of
813 -- a tagged type cleans constant indications from its scope).
815 elsif Nkind
(Parent
(N
)) = N_Unchecked_Type_Conversion
816 and then (Etype
(Parent
(N
)) = RTE
(RE_Prim_Ptr
)
818 Etype
(Parent
(N
)) = RTE
(RE_Size_Ptr
))
819 and then Is_Dispatching_Operation
820 (Directly_Designated_Type
(Etype
(N
)))
828 -- In the static elaboration model, treat the attribute reference
829 -- as a call for elaboration purposes. Suppress this treatment
830 -- under debug flag. In any case, we are all done.
832 if not Dynamic_Elaboration_Checks
and not Debug_Flag_Dot_UU
then
838 -- Component is an operation of a protected type
840 elsif Nkind
(P
) = N_Selected_Component
841 and then Is_Overloadable
(Entity
(Selector_Name
(P
)))
843 if Ekind
(Entity
(Selector_Name
(P
))) = E_Entry
then
844 Error_Attr_P
("prefix of % attribute must be subprogram");
847 Build_Access_Subprogram_Type
(Selector_Name
(P
));
851 -- Deal with incorrect reference to a type, but note that some
852 -- accesses are allowed: references to the current type instance,
853 -- or in Ada 2005 self-referential pointer in a default-initialized
856 if Is_Entity_Name
(P
) then
859 -- The reference may appear in an aggregate that has been expanded
860 -- into a loop. Locate scope of type definition, if any.
862 Scop
:= Current_Scope
;
863 while Ekind
(Scop
) = E_Loop
loop
864 Scop
:= Scope
(Scop
);
867 if Is_Type
(Typ
) then
869 -- OK if we are within the scope of a limited type
870 -- let's mark the component as having per object constraint
872 if Is_Anonymous_Tagged_Base
(Scop
, Typ
) then
880 Q
: Node_Id
:= Parent
(N
);
884 and then Nkind
(Q
) /= N_Component_Declaration
890 Set_Has_Per_Object_Constraint
891 (Defining_Identifier
(Q
), True);
895 if Nkind
(P
) = N_Expanded_Name
then
897 ("current instance prefix must be a direct name", P
);
900 -- If a current instance attribute appears in a component
901 -- constraint it must appear alone; other contexts (spec-
902 -- expressions, within a task body) are not subject to this
905 if not In_Spec_Expression
906 and then not Has_Completion
(Scop
)
908 Nkind_In
(Parent
(N
), N_Discriminant_Association
,
909 N_Index_Or_Discriminant_Constraint
)
912 ("current instance attribute must appear alone", N
);
915 if Is_CPP_Class
(Root_Type
(Typ
)) then
917 ("??current instance unsupported for derivations of "
918 & "'C'P'P types", N
);
921 -- OK if we are in initialization procedure for the type
922 -- in question, in which case the reference to the type
923 -- is rewritten as a reference to the current object.
925 elsif Ekind
(Scop
) = E_Procedure
926 and then Is_Init_Proc
(Scop
)
927 and then Etype
(First_Formal
(Scop
)) = Typ
930 Make_Attribute_Reference
(Loc
,
931 Prefix
=> Make_Identifier
(Loc
, Name_uInit
),
932 Attribute_Name
=> Name_Unrestricted_Access
));
936 -- OK if a task type, this test needs sharpening up ???
938 elsif Is_Task_Type
(Typ
) then
941 -- OK if self-reference in an aggregate in Ada 2005, and
942 -- the reference comes from a copied default expression.
944 -- Note that we check legality of self-reference even if the
945 -- expression comes from source, e.g. when a single component
946 -- association in an aggregate has a box association.
948 elsif Ada_Version
>= Ada_2005
949 and then OK_Self_Reference
953 -- OK if reference to current instance of a protected object
955 elsif Is_Protected_Self_Reference
(P
) then
958 -- Otherwise we have an error case
961 Error_Attr
("% attribute cannot be applied to type", P
);
967 -- If we fall through, we have a normal access to object case
969 -- Unrestricted_Access is (for now) legal wherever an allocator would
970 -- be legal, so its Etype is set to E_Allocator. The expected type
971 -- of the other attributes is a general access type, and therefore
972 -- we label them with E_Access_Attribute_Type.
974 if not Is_Overloaded
(P
) then
975 Acc_Type
:= Build_Access_Object_Type
(P_Type
);
976 Set_Etype
(N
, Acc_Type
);
980 Index
: Interp_Index
;
983 Set_Etype
(N
, Any_Type
);
984 Get_First_Interp
(P
, Index
, It
);
985 while Present
(It
.Typ
) loop
986 Acc_Type
:= Build_Access_Object_Type
(It
.Typ
);
987 Add_One_Interp
(N
, Acc_Type
, Acc_Type
);
988 Get_Next_Interp
(Index
, It
);
993 -- Special cases when we can find a prefix that is an entity name
1002 if Is_Entity_Name
(PP
) then
1005 -- If we have an access to an object, and the attribute
1006 -- comes from source, then set the object as potentially
1007 -- source modified. We do this because the resulting access
1008 -- pointer can be used to modify the variable, and we might
1009 -- not detect this, leading to some junk warnings.
1011 -- We only do this for source references, since otherwise
1012 -- we can suppress warnings, e.g. from the unrestricted
1013 -- access generated for validity checks in -gnatVa mode.
1015 if Comes_From_Source
(N
) then
1016 Set_Never_Set_In_Source
(Ent
, False);
1019 -- Mark entity as address taken, and kill current values
1021 Set_Address_Taken
(Ent
);
1022 Kill_Current_Values
(Ent
);
1025 elsif Nkind_In
(PP
, N_Selected_Component
,
1026 N_Indexed_Component
)
1036 -- Check for aliased view.. We allow a nonaliased prefix when within
1037 -- an instance because the prefix may have been a tagged formal
1038 -- object, which is defined to be aliased even when the actual
1039 -- might not be (other instance cases will have been caught in the
1040 -- generic). Similarly, within an inlined body we know that the
1041 -- attribute is legal in the original subprogram, and therefore
1042 -- legal in the expansion.
1044 if not Is_Aliased_View
(P
)
1045 and then not In_Instance
1046 and then not In_Inlined_Body
1047 and then Comes_From_Source
(N
)
1049 -- Here we have a non-aliased view. This is illegal unless we
1050 -- have the case of Unrestricted_Access, where for now we allow
1051 -- this (we will reject later if expected type is access to an
1052 -- unconstrained array with a thin pointer).
1054 -- No need for an error message on a generated access reference
1055 -- for the controlling argument in a dispatching call: error will
1056 -- be reported when resolving the call.
1058 if Aname
/= Name_Unrestricted_Access
then
1059 Error_Attr_P
("prefix of % attribute must be aliased");
1060 Check_No_Implicit_Aliasing
(P
);
1062 -- For Unrestricted_Access, record that prefix is not aliased
1063 -- to simplify legality check later on.
1066 Set_Non_Aliased_Prefix
(N
);
1069 -- If we have an aliased view, and we have Unrestricted_Access, then
1070 -- output a warning that Unchecked_Access would have been fine, and
1071 -- change the node to be Unchecked_Access.
1074 -- For now, hold off on this change ???
1078 end Analyze_Access_Attribute
;
1080 ----------------------------------
1081 -- Analyze_Attribute_Old_Result --
1082 ----------------------------------
1084 procedure Analyze_Attribute_Old_Result
1085 (Legal
: out Boolean;
1086 Spec_Id
: out Entity_Id
)
1088 procedure Check_Placement_In_Check
(Prag
: Node_Id
);
1089 -- Verify that the attribute appears within pragma Check that mimics
1092 procedure Check_Placement_In_Contract_Cases
(Prag
: Node_Id
);
1093 -- Verify that the attribute appears within a consequence of aspect
1094 -- or pragma Contract_Cases denoted by Prag.
1096 procedure Check_Placement_In_Test_Case
(Prag
: Node_Id
);
1097 -- Verify that the attribute appears within the "Ensures" argument of
1098 -- aspect or pragma Test_Case denoted by Prag.
1102 Encl_Nod
: Node_Id
) return Boolean;
1103 -- Subsidiary to Check_Placemenet_In_XXX. Determine whether arbitrary
1104 -- node Nod is within enclosing node Encl_Nod.
1106 procedure Placement_Error
;
1107 -- Emit a general error when the attributes does not appear in a
1108 -- postcondition-like aspect or pragma.
1110 ------------------------------
1111 -- Check_Placement_In_Check --
1112 ------------------------------
1114 procedure Check_Placement_In_Check
(Prag
: Node_Id
) is
1115 Args
: constant List_Id
:= Pragma_Argument_Associations
(Prag
);
1116 Nam
: constant Name_Id
:= Chars
(Get_Pragma_Arg
(First
(Args
)));
1119 -- The "Name" argument of pragma Check denotes a postcondition
1121 if Nam_In
(Nam
, Name_Post
,
1128 -- Otherwise the placement of the attribute is illegal
1133 end Check_Placement_In_Check
;
1135 ---------------------------------------
1136 -- Check_Placement_In_Contract_Cases --
1137 ---------------------------------------
1139 procedure Check_Placement_In_Contract_Cases
(Prag
: Node_Id
) is
1145 -- Obtain the argument of the aspect or pragma
1147 if Nkind
(Prag
) = N_Aspect_Specification
then
1150 Arg
:= First
(Pragma_Argument_Associations
(Prag
));
1153 Cases
:= Expression
(Arg
);
1155 if Present
(Component_Associations
(Cases
)) then
1156 CCase
:= First
(Component_Associations
(Cases
));
1157 while Present
(CCase
) loop
1159 -- Detect whether the attribute appears within the
1160 -- consequence of the current contract case.
1162 if Nkind
(CCase
) = N_Component_Association
1163 and then Is_Within
(N
, Expression
(CCase
))
1172 -- Otherwise aspect or pragma Contract_Cases is either malformed
1173 -- or the attribute does not appear within a consequence.
1176 ("attribute % must appear in the consequence of a contract case",
1178 end Check_Placement_In_Contract_Cases
;
1180 ----------------------------------
1181 -- Check_Placement_In_Test_Case --
1182 ----------------------------------
1184 procedure Check_Placement_In_Test_Case
(Prag
: Node_Id
) is
1185 Arg
: constant Node_Id
:=
1188 Arg_Nam
=> Name_Ensures
,
1189 From_Aspect
=> Nkind
(Prag
) = N_Aspect_Specification
);
1192 -- Detect whether the attribute appears within the "Ensures"
1193 -- expression of aspect or pragma Test_Case.
1195 if Present
(Arg
) and then Is_Within
(N
, Arg
) then
1200 ("attribute % must appear in the ensures expression of a "
1203 end Check_Placement_In_Test_Case
;
1211 Encl_Nod
: Node_Id
) return Boolean
1217 while Present
(Par
) loop
1218 if Par
= Encl_Nod
then
1221 -- Prevent the search from going too far
1223 elsif Is_Body_Or_Package_Declaration
(Par
) then
1227 Par
:= Parent
(Par
);
1233 ---------------------
1234 -- Placement_Error --
1235 ---------------------
1237 procedure Placement_Error
is
1239 if Aname
= Name_Old
then
1240 Error_Attr
("attribute % can only appear in postcondition", P
);
1242 -- Specialize the error message for attribute 'Result
1246 ("attribute % can only appear in postcondition of function",
1249 end Placement_Error
;
1255 Subp_Decl
: Node_Id
;
1257 -- Start of processing for Analyze_Attribute_Old_Result
1260 -- Assume that the attribute is illegal
1265 -- Traverse the parent chain to find the aspect or pragma where the
1266 -- attribute resides.
1269 while Present
(Prag
) loop
1270 if Nkind_In
(Prag
, N_Aspect_Specification
, N_Pragma
) then
1273 -- Prevent the search from going too far
1275 elsif Is_Body_Or_Package_Declaration
(Prag
) then
1279 Prag
:= Parent
(Prag
);
1282 -- The attribute is allowed to appear only in postcondition-like
1283 -- aspects or pragmas.
1285 if Nkind_In
(Prag
, N_Aspect_Specification
, N_Pragma
) then
1286 if Nkind
(Prag
) = N_Aspect_Specification
then
1287 Prag_Nam
:= Chars
(Identifier
(Prag
));
1289 Prag_Nam
:= Pragma_Name
(Prag
);
1292 if Prag_Nam
= Name_Check
then
1293 Check_Placement_In_Check
(Prag
);
1295 elsif Prag_Nam
= Name_Contract_Cases
then
1296 Check_Placement_In_Contract_Cases
(Prag
);
1298 -- Attribute 'Result is allowed to appear in aspect or pragma
1299 -- [Refined_]Depends (SPARK RM 6.1.5(11)).
1301 elsif Nam_In
(Prag_Nam
, Name_Depends
, Name_Refined_Depends
)
1302 and then Aname
= Name_Result
1306 elsif Nam_In
(Prag_Nam
, Name_Post
,
1313 elsif Prag_Nam
= Name_Test_Case
then
1314 Check_Placement_In_Test_Case
(Prag
);
1321 -- Otherwise the placement of the attribute is illegal
1328 -- Find the related subprogram subject to the aspect or pragma
1330 if Nkind
(Prag
) = N_Aspect_Specification
then
1331 Subp_Decl
:= Parent
(Prag
);
1333 Subp_Decl
:= Find_Related_Subprogram_Or_Body
(Prag
);
1336 -- The aspect or pragma where the attribute resides should be
1337 -- associated with a subprogram declaration or a body. If this is not
1338 -- the case, then the aspect or pragma is illegal. Return as analysis
1339 -- cannot be carried out.
1341 if not Nkind_In
(Subp_Decl
, N_Abstract_Subprogram_Declaration
,
1342 N_Entry_Declaration
,
1343 N_Generic_Subprogram_Declaration
,
1345 N_Subprogram_Body_Stub
,
1346 N_Subprogram_Declaration
)
1351 -- If we get here, then the attribute is legal
1354 Spec_Id
:= Corresponding_Spec_Of
(Subp_Decl
);
1355 end Analyze_Attribute_Old_Result
;
1357 ---------------------------------
1358 -- Bad_Attribute_For_Predicate --
1359 ---------------------------------
1361 procedure Bad_Attribute_For_Predicate
is
1363 if Is_Scalar_Type
(P_Type
)
1364 and then Comes_From_Source
(N
)
1366 Error_Msg_Name_1
:= Aname
;
1367 Bad_Predicated_Subtype_Use
1368 ("type& has predicates, attribute % not allowed", N
, P_Type
);
1370 end Bad_Attribute_For_Predicate
;
1372 --------------------------------
1373 -- Check_Array_Or_Scalar_Type --
1374 --------------------------------
1376 procedure Check_Array_Or_Scalar_Type
is
1380 -- Dimension number for array attributes
1383 -- Case of string literal or string literal subtype. These cases
1384 -- cannot arise from legal Ada code, but the expander is allowed
1385 -- to generate them. They require special handling because string
1386 -- literal subtypes do not have standard bounds (the whole idea
1387 -- of these subtypes is to avoid having to generate the bounds)
1389 if Ekind
(P_Type
) = E_String_Literal_Subtype
then
1390 Set_Etype
(N
, Etype
(First_Index
(P_Base_Type
)));
1395 elsif Is_Scalar_Type
(P_Type
) then
1398 if Present
(E1
) then
1399 Error_Attr
("invalid argument in % attribute", E1
);
1401 Set_Etype
(N
, P_Base_Type
);
1405 -- The following is a special test to allow 'First to apply to
1406 -- private scalar types if the attribute comes from generated
1407 -- code. This occurs in the case of Normalize_Scalars code.
1409 elsif Is_Private_Type
(P_Type
)
1410 and then Present
(Full_View
(P_Type
))
1411 and then Is_Scalar_Type
(Full_View
(P_Type
))
1412 and then not Comes_From_Source
(N
)
1414 Set_Etype
(N
, Implementation_Base_Type
(P_Type
));
1416 -- Array types other than string literal subtypes handled above
1421 -- We know prefix is an array type, or the name of an array
1422 -- object, and that the expression, if present, is static
1423 -- and within the range of the dimensions of the type.
1425 pragma Assert
(Is_Array_Type
(P_Type
));
1426 Index
:= First_Index
(P_Base_Type
);
1430 -- First dimension assumed
1432 Set_Etype
(N
, Base_Type
(Etype
(Index
)));
1435 D
:= UI_To_Int
(Intval
(E1
));
1437 for J
in 1 .. D
- 1 loop
1441 Set_Etype
(N
, Base_Type
(Etype
(Index
)));
1442 Set_Etype
(E1
, Standard_Integer
);
1445 end Check_Array_Or_Scalar_Type
;
1447 ----------------------
1448 -- Check_Array_Type --
1449 ----------------------
1451 procedure Check_Array_Type
is
1453 -- Dimension number for array attributes
1456 -- If the type is a string literal type, then this must be generated
1457 -- internally, and no further check is required on its legality.
1459 if Ekind
(P_Type
) = E_String_Literal_Subtype
then
1462 -- If the type is a composite, it is an illegal aggregate, no point
1465 elsif P_Type
= Any_Composite
then
1466 raise Bad_Attribute
;
1469 -- Normal case of array type or subtype
1471 Check_Either_E0_Or_E1
;
1474 if Is_Array_Type
(P_Type
) then
1475 if not Is_Constrained
(P_Type
)
1476 and then Is_Entity_Name
(P
)
1477 and then Is_Type
(Entity
(P
))
1479 -- Note: we do not call Error_Attr here, since we prefer to
1480 -- continue, using the relevant index type of the array,
1481 -- even though it is unconstrained. This gives better error
1482 -- recovery behavior.
1484 Error_Msg_Name_1
:= Aname
;
1486 ("prefix for % attribute must be constrained array", P
);
1489 -- The attribute reference freezes the type, and thus the
1490 -- component type, even if the attribute may not depend on the
1491 -- component. Diagnose arrays with incomplete components now.
1492 -- If the prefix is an access to array, this does not freeze
1493 -- the designated type.
1495 if Nkind
(P
) /= N_Explicit_Dereference
then
1496 Check_Fully_Declared
(Component_Type
(P_Type
), P
);
1499 D
:= Number_Dimensions
(P_Type
);
1502 if Is_Private_Type
(P_Type
) then
1503 Error_Attr_P
("prefix for % attribute may not be private type");
1505 elsif Is_Access_Type
(P_Type
)
1506 and then Is_Array_Type
(Designated_Type
(P_Type
))
1507 and then Is_Entity_Name
(P
)
1508 and then Is_Type
(Entity
(P
))
1510 Error_Attr_P
("prefix of % attribute cannot be access type");
1512 elsif Attr_Id
= Attribute_First
1514 Attr_Id
= Attribute_Last
1516 Error_Attr
("invalid prefix for % attribute", P
);
1519 Error_Attr_P
("prefix for % attribute must be array");
1523 if Present
(E1
) then
1524 Resolve
(E1
, Any_Integer
);
1525 Set_Etype
(E1
, Standard_Integer
);
1527 if not Is_OK_Static_Expression
(E1
)
1528 or else Raises_Constraint_Error
(E1
)
1530 Flag_Non_Static_Expr
1531 ("expression for dimension must be static!", E1
);
1534 elsif UI_To_Int
(Expr_Value
(E1
)) > D
1535 or else UI_To_Int
(Expr_Value
(E1
)) < 1
1537 Error_Attr
("invalid dimension number for array type", E1
);
1541 if (Style_Check
and Style_Check_Array_Attribute_Index
)
1542 and then Comes_From_Source
(N
)
1544 Style
.Check_Array_Attribute_Index
(N
, E1
, D
);
1546 end Check_Array_Type
;
1548 -------------------------
1549 -- Check_Asm_Attribute --
1550 -------------------------
1552 procedure Check_Asm_Attribute
is
1557 -- Check first argument is static string expression
1559 Analyze_And_Resolve
(E1
, Standard_String
);
1561 if Etype
(E1
) = Any_Type
then
1564 elsif not Is_OK_Static_Expression
(E1
) then
1565 Flag_Non_Static_Expr
1566 ("constraint argument must be static string expression!", E1
);
1570 -- Check second argument is right type
1572 Analyze_And_Resolve
(E2
, Entity
(P
));
1574 -- Note: that is all we need to do, we don't need to check
1575 -- that it appears in a correct context. The Ada type system
1576 -- will do that for us.
1578 end Check_Asm_Attribute
;
1580 ---------------------
1581 -- Check_Component --
1582 ---------------------
1584 procedure Check_Component
is
1588 if Nkind
(P
) /= N_Selected_Component
1590 (Ekind
(Entity
(Selector_Name
(P
))) /= E_Component
1592 Ekind
(Entity
(Selector_Name
(P
))) /= E_Discriminant
)
1594 Error_Attr_P
("prefix for % attribute must be selected component");
1596 end Check_Component
;
1598 ------------------------------------
1599 -- Check_Decimal_Fixed_Point_Type --
1600 ------------------------------------
1602 procedure Check_Decimal_Fixed_Point_Type
is
1606 if not Is_Decimal_Fixed_Point_Type
(P_Type
) then
1607 Error_Attr_P
("prefix of % attribute must be decimal type");
1609 end Check_Decimal_Fixed_Point_Type
;
1611 -----------------------
1612 -- Check_Dereference --
1613 -----------------------
1615 procedure Check_Dereference
is
1618 -- Case of a subtype mark
1620 if Is_Entity_Name
(P
) and then Is_Type
(Entity
(P
)) then
1624 -- Case of an expression
1628 if Is_Access_Type
(P_Type
) then
1630 -- If there is an implicit dereference, then we must freeze the
1631 -- designated type of the access type, since the type of the
1632 -- referenced array is this type (see AI95-00106).
1634 -- As done elsewhere, freezing must not happen when pre-analyzing
1635 -- a pre- or postcondition or a default value for an object or for
1636 -- a formal parameter.
1638 if not In_Spec_Expression
then
1639 Freeze_Before
(N
, Designated_Type
(P_Type
));
1643 Make_Explicit_Dereference
(Sloc
(P
),
1644 Prefix
=> Relocate_Node
(P
)));
1646 Analyze_And_Resolve
(P
);
1647 P_Type
:= Etype
(P
);
1649 if P_Type
= Any_Type
then
1650 raise Bad_Attribute
;
1653 P_Base_Type
:= Base_Type
(P_Type
);
1655 end Check_Dereference
;
1657 -------------------------
1658 -- Check_Discrete_Type --
1659 -------------------------
1661 procedure Check_Discrete_Type
is
1665 if not Is_Discrete_Type
(P_Type
) then
1666 Error_Attr_P
("prefix of % attribute must be discrete type");
1668 end Check_Discrete_Type
;
1674 procedure Check_E0
is
1676 if Present
(E1
) then
1677 Unexpected_Argument
(E1
);
1685 procedure Check_E1
is
1687 Check_Either_E0_Or_E1
;
1691 -- Special-case attributes that are functions and that appear as
1692 -- the prefix of another attribute. Error is posted on parent.
1694 if Nkind
(Parent
(N
)) = N_Attribute_Reference
1695 and then Nam_In
(Attribute_Name
(Parent
(N
)), Name_Address
,
1699 Error_Msg_Name_1
:= Attribute_Name
(Parent
(N
));
1700 Error_Msg_N
("illegal prefix for % attribute", Parent
(N
));
1701 Set_Etype
(Parent
(N
), Any_Type
);
1702 Set_Entity
(Parent
(N
), Any_Type
);
1703 raise Bad_Attribute
;
1706 Error_Attr
("missing argument for % attribute", N
);
1715 procedure Check_E2
is
1718 Error_Attr
("missing arguments for % attribute (2 required)", N
);
1720 Error_Attr
("missing argument for % attribute (2 required)", N
);
1724 ---------------------------
1725 -- Check_Either_E0_Or_E1 --
1726 ---------------------------
1728 procedure Check_Either_E0_Or_E1
is
1730 if Present
(E2
) then
1731 Unexpected_Argument
(E2
);
1733 end Check_Either_E0_Or_E1
;
1735 ----------------------
1736 -- Check_Enum_Image --
1737 ----------------------
1739 procedure Check_Enum_Image
is
1743 -- When an enumeration type appears in an attribute reference, all
1744 -- literals of the type are marked as referenced. This must only be
1745 -- done if the attribute reference appears in the current source.
1746 -- Otherwise the information on references may differ between a
1747 -- normal compilation and one that performs inlining.
1749 if Is_Enumeration_Type
(P_Base_Type
)
1750 and then In_Extended_Main_Code_Unit
(N
)
1752 Lit
:= First_Literal
(P_Base_Type
);
1753 while Present
(Lit
) loop
1754 Set_Referenced
(Lit
);
1758 end Check_Enum_Image
;
1760 ----------------------------
1761 -- Check_First_Last_Valid --
1762 ----------------------------
1764 procedure Check_First_Last_Valid
is
1766 Check_Discrete_Type
;
1768 -- Freeze the subtype now, so that the following test for predicates
1769 -- works (we set the predicates stuff up at freeze time)
1771 Insert_Actions
(N
, Freeze_Entity
(P_Type
, P
));
1773 -- Now test for dynamic predicate
1775 if Has_Predicates
(P_Type
)
1776 and then not (Has_Static_Predicate
(P_Type
))
1779 ("prefix of % attribute may not have dynamic predicate");
1782 -- Check non-static subtype
1784 if not Is_OK_Static_Subtype
(P_Type
) then
1785 Error_Attr_P
("prefix of % attribute must be a static subtype");
1788 -- Test case for no values
1790 if Expr_Value
(Type_Low_Bound
(P_Type
)) >
1791 Expr_Value
(Type_High_Bound
(P_Type
))
1792 or else (Has_Predicates
(P_Type
)
1794 Is_Empty_List
(Static_Discrete_Predicate
(P_Type
)))
1797 ("prefix of % attribute must be subtype with at least one "
1800 end Check_First_Last_Valid
;
1802 ----------------------------
1803 -- Check_Fixed_Point_Type --
1804 ----------------------------
1806 procedure Check_Fixed_Point_Type
is
1810 if not Is_Fixed_Point_Type
(P_Type
) then
1811 Error_Attr_P
("prefix of % attribute must be fixed point type");
1813 end Check_Fixed_Point_Type
;
1815 ------------------------------
1816 -- Check_Fixed_Point_Type_0 --
1817 ------------------------------
1819 procedure Check_Fixed_Point_Type_0
is
1821 Check_Fixed_Point_Type
;
1823 end Check_Fixed_Point_Type_0
;
1825 -------------------------------
1826 -- Check_Floating_Point_Type --
1827 -------------------------------
1829 procedure Check_Floating_Point_Type
is
1833 if not Is_Floating_Point_Type
(P_Type
) then
1834 Error_Attr_P
("prefix of % attribute must be float type");
1836 end Check_Floating_Point_Type
;
1838 ---------------------------------
1839 -- Check_Floating_Point_Type_0 --
1840 ---------------------------------
1842 procedure Check_Floating_Point_Type_0
is
1844 Check_Floating_Point_Type
;
1846 end Check_Floating_Point_Type_0
;
1848 ---------------------------------
1849 -- Check_Floating_Point_Type_1 --
1850 ---------------------------------
1852 procedure Check_Floating_Point_Type_1
is
1854 Check_Floating_Point_Type
;
1856 end Check_Floating_Point_Type_1
;
1858 ---------------------------------
1859 -- Check_Floating_Point_Type_2 --
1860 ---------------------------------
1862 procedure Check_Floating_Point_Type_2
is
1864 Check_Floating_Point_Type
;
1866 end Check_Floating_Point_Type_2
;
1868 ------------------------
1869 -- Check_Integer_Type --
1870 ------------------------
1872 procedure Check_Integer_Type
is
1876 if not Is_Integer_Type
(P_Type
) then
1877 Error_Attr_P
("prefix of % attribute must be integer type");
1879 end Check_Integer_Type
;
1881 --------------------------------
1882 -- Check_Modular_Integer_Type --
1883 --------------------------------
1885 procedure Check_Modular_Integer_Type
is
1889 if not Is_Modular_Integer_Type
(P_Type
) then
1891 ("prefix of % attribute must be modular integer type");
1893 end Check_Modular_Integer_Type
;
1895 ------------------------
1896 -- Check_Not_CPP_Type --
1897 ------------------------
1899 procedure Check_Not_CPP_Type
is
1901 if Is_Tagged_Type
(Etype
(P
))
1902 and then Convention
(Etype
(P
)) = Convention_CPP
1903 and then Is_CPP_Class
(Root_Type
(Etype
(P
)))
1906 ("invalid use of % attribute with 'C'P'P tagged type");
1908 end Check_Not_CPP_Type
;
1910 -------------------------------
1911 -- Check_Not_Incomplete_Type --
1912 -------------------------------
1914 procedure Check_Not_Incomplete_Type
is
1919 -- Ada 2005 (AI-50217, AI-326): If the prefix is an explicit
1920 -- dereference we have to check wrong uses of incomplete types
1921 -- (other wrong uses are checked at their freezing point).
1923 -- In Ada 2012, incomplete types can appear in subprogram
1924 -- profiles, but formals with incomplete types cannot be the
1925 -- prefix of attributes.
1927 -- Example 1: Limited-with
1929 -- limited with Pkg;
1931 -- type Acc is access Pkg.T;
1933 -- S : Integer := X.all'Size; -- ERROR
1936 -- Example 2: Tagged incomplete
1938 -- type T is tagged;
1939 -- type Acc is access all T;
1941 -- S : constant Integer := X.all'Size; -- ERROR
1942 -- procedure Q (Obj : Integer := X.all'Alignment); -- ERROR
1944 if Ada_Version
>= Ada_2005
1945 and then Nkind
(P
) = N_Explicit_Dereference
1948 while Nkind
(E
) = N_Explicit_Dereference
loop
1954 if From_Limited_With
(Typ
) then
1956 ("prefix of % attribute cannot be an incomplete type");
1958 -- If the prefix is an access type check the designated type
1960 elsif Is_Access_Type
(Typ
)
1961 and then Nkind
(P
) = N_Explicit_Dereference
1963 Typ
:= Directly_Designated_Type
(Typ
);
1966 if Is_Class_Wide_Type
(Typ
) then
1967 Typ
:= Root_Type
(Typ
);
1970 -- A legal use of a shadow entity occurs only when the unit where
1971 -- the non-limited view resides is imported via a regular with
1972 -- clause in the current body. Such references to shadow entities
1973 -- may occur in subprogram formals.
1975 if Is_Incomplete_Type
(Typ
)
1976 and then From_Limited_With
(Typ
)
1977 and then Present
(Non_Limited_View
(Typ
))
1978 and then Is_Legal_Shadow_Entity_In_Body
(Typ
)
1980 Typ
:= Non_Limited_View
(Typ
);
1983 -- If still incomplete, it can be a local incomplete type, or a
1984 -- limited view whose scope is also a limited view.
1986 if Ekind
(Typ
) = E_Incomplete_Type
then
1987 if not From_Limited_With
(Typ
)
1988 and then No
(Full_View
(Typ
))
1991 ("prefix of % attribute cannot be an incomplete type");
1993 -- The limited view may be available indirectly through
1994 -- an intermediate unit. If the non-limited view is available
1995 -- the attribute reference is legal.
1997 elsif From_Limited_With
(Typ
)
1999 (No
(Non_Limited_View
(Typ
))
2000 or else Is_Incomplete_Type
(Non_Limited_View
(Typ
)))
2003 ("prefix of % attribute cannot be an incomplete type");
2007 -- Ada 2012 : formals in bodies may be incomplete, but no attribute
2010 elsif Is_Entity_Name
(P
)
2011 and then Is_Formal
(Entity
(P
))
2012 and then Is_Incomplete_Type
(Etype
(Etype
(P
)))
2015 ("prefix of % attribute cannot be an incomplete type");
2018 if not Is_Entity_Name
(P
)
2019 or else not Is_Type
(Entity
(P
))
2020 or else In_Spec_Expression
2024 Check_Fully_Declared
(P_Type
, P
);
2026 end Check_Not_Incomplete_Type
;
2028 ----------------------------
2029 -- Check_Object_Reference --
2030 ----------------------------
2032 procedure Check_Object_Reference
(P
: Node_Id
) is
2036 -- If we need an object, and we have a prefix that is the name of
2037 -- a function entity, convert it into a function call.
2039 if Is_Entity_Name
(P
)
2040 and then Ekind
(Entity
(P
)) = E_Function
2042 Rtyp
:= Etype
(Entity
(P
));
2045 Make_Function_Call
(Sloc
(P
),
2046 Name
=> Relocate_Node
(P
)));
2048 Analyze_And_Resolve
(P
, Rtyp
);
2050 -- Otherwise we must have an object reference
2052 elsif not Is_Object_Reference
(P
) then
2053 Error_Attr_P
("prefix of % attribute must be object");
2055 end Check_Object_Reference
;
2057 ----------------------------
2058 -- Check_PolyORB_Attribute --
2059 ----------------------------
2061 procedure Check_PolyORB_Attribute
is
2063 Validate_Non_Static_Attribute_Function_Call
;
2068 if Get_PCS_Name
/= Name_PolyORB_DSA
then
2070 ("attribute% requires the 'Poly'O'R'B 'P'C'S", N
);
2072 end Check_PolyORB_Attribute
;
2074 ------------------------
2075 -- Check_Program_Unit --
2076 ------------------------
2078 procedure Check_Program_Unit
is
2080 if Is_Entity_Name
(P
) then
2082 K
: constant Entity_Kind
:= Ekind
(Entity
(P
));
2083 T
: constant Entity_Id
:= Etype
(Entity
(P
));
2086 if K
in Subprogram_Kind
2087 or else K
in Task_Kind
2088 or else K
in Protected_Kind
2089 or else K
= E_Package
2090 or else K
in Generic_Unit_Kind
2091 or else (K
= E_Variable
2095 Is_Protected_Type
(T
)))
2102 Error_Attr_P
("prefix of % attribute must be program unit");
2103 end Check_Program_Unit
;
2105 ---------------------
2106 -- Check_Real_Type --
2107 ---------------------
2109 procedure Check_Real_Type
is
2113 if not Is_Real_Type
(P_Type
) then
2114 Error_Attr_P
("prefix of % attribute must be real type");
2116 end Check_Real_Type
;
2118 -----------------------
2119 -- Check_Scalar_Type --
2120 -----------------------
2122 procedure Check_Scalar_Type
is
2126 if not Is_Scalar_Type
(P_Type
) then
2127 Error_Attr_P
("prefix of % attribute must be scalar type");
2129 end Check_Scalar_Type
;
2131 ------------------------------------------
2132 -- Check_SPARK_05_Restriction_On_Attribute --
2133 ------------------------------------------
2135 procedure Check_SPARK_05_Restriction_On_Attribute
is
2137 Error_Msg_Name_1
:= Aname
;
2138 Check_SPARK_05_Restriction
("attribute % is not allowed", P
);
2139 end Check_SPARK_05_Restriction_On_Attribute
;
2141 ---------------------------
2142 -- Check_Standard_Prefix --
2143 ---------------------------
2145 procedure Check_Standard_Prefix
is
2149 if Nkind
(P
) /= N_Identifier
or else Chars
(P
) /= Name_Standard
then
2150 Error_Attr
("only allowed prefix for % attribute is Standard", P
);
2152 end Check_Standard_Prefix
;
2154 ----------------------------
2155 -- Check_Stream_Attribute --
2156 ----------------------------
2158 procedure Check_Stream_Attribute
(Nam
: TSS_Name_Type
) is
2162 In_Shared_Var_Procs
: Boolean;
2163 -- True when compiling System.Shared_Storage.Shared_Var_Procs body.
2164 -- For this runtime package (always compiled in GNAT mode), we allow
2165 -- stream attributes references for limited types for the case where
2166 -- shared passive objects are implemented using stream attributes,
2167 -- which is the default in GNAT's persistent storage implementation.
2170 Validate_Non_Static_Attribute_Function_Call
;
2172 -- With the exception of 'Input, Stream attributes are procedures,
2173 -- and can only appear at the position of procedure calls. We check
2174 -- for this here, before they are rewritten, to give a more precise
2177 if Nam
= TSS_Stream_Input
then
2180 elsif Is_List_Member
(N
)
2181 and then not Nkind_In
(Parent
(N
), N_Procedure_Call_Statement
,
2188 ("invalid context for attribute%, which is a procedure", N
);
2192 Btyp
:= Implementation_Base_Type
(P_Type
);
2194 -- Stream attributes not allowed on limited types unless the
2195 -- attribute reference was generated by the expander (in which
2196 -- case the underlying type will be used, as described in Sinfo),
2197 -- or the attribute was specified explicitly for the type itself
2198 -- or one of its ancestors (taking visibility rules into account if
2199 -- in Ada 2005 mode), or a pragma Stream_Convert applies to Btyp
2200 -- (with no visibility restriction).
2203 Gen_Body
: constant Node_Id
:= Enclosing_Generic_Body
(N
);
2205 if Present
(Gen_Body
) then
2206 In_Shared_Var_Procs
:=
2207 Is_RTE
(Corresponding_Spec
(Gen_Body
), RE_Shared_Var_Procs
);
2209 In_Shared_Var_Procs
:= False;
2213 if (Comes_From_Source
(N
)
2214 and then not (In_Shared_Var_Procs
or In_Instance
))
2215 and then not Stream_Attribute_Available
(P_Type
, Nam
)
2216 and then not Has_Rep_Pragma
(Btyp
, Name_Stream_Convert
)
2218 Error_Msg_Name_1
:= Aname
;
2220 if Is_Limited_Type
(P_Type
) then
2222 ("limited type& has no% attribute", P
, P_Type
);
2223 Explain_Limited_Type
(P_Type
, P
);
2226 ("attribute% for type& is not available", P
, P_Type
);
2230 -- Check for no stream operations allowed from No_Tagged_Streams
2232 if Is_Tagged_Type
(P_Type
)
2233 and then Present
(No_Tagged_Streams_Pragma
(P_Type
))
2235 Error_Msg_Sloc
:= Sloc
(No_Tagged_Streams_Pragma
(P_Type
));
2237 ("no stream operations for & (No_Tagged_Streams #)", N
, P_Type
);
2241 -- Check restriction violations
2243 -- First check the No_Streams restriction, which prohibits the use
2244 -- of explicit stream attributes in the source program. We do not
2245 -- prevent the occurrence of stream attributes in generated code,
2246 -- for instance those generated implicitly for dispatching purposes.
2248 if Comes_From_Source
(N
) then
2249 Check_Restriction
(No_Streams
, P
);
2252 -- AI05-0057: if restriction No_Default_Stream_Attributes is active,
2253 -- it is illegal to use a predefined elementary type stream attribute
2254 -- either by itself, or more importantly as part of the attribute
2255 -- subprogram for a composite type. However, if the broader
2256 -- restriction No_Streams is active, stream operations are not
2257 -- generated, and there is no error.
2259 if Restriction_Active
(No_Default_Stream_Attributes
)
2260 and then not Restriction_Active
(No_Streams
)
2266 if Nam
= TSS_Stream_Input
2268 Nam
= TSS_Stream_Read
2271 Type_Without_Stream_Operation
(P_Type
, TSS_Stream_Read
);
2274 Type_Without_Stream_Operation
(P_Type
, TSS_Stream_Write
);
2278 Check_Restriction
(No_Default_Stream_Attributes
, N
);
2281 ("missing user-defined Stream Read or Write for type&",
2283 if not Is_Elementary_Type
(P_Type
) then
2285 ("\which is a component of type&", N
, P_Type
);
2291 -- Check special case of Exception_Id and Exception_Occurrence which
2292 -- are not allowed for restriction No_Exception_Registration.
2294 if Restriction_Check_Required
(No_Exception_Registration
)
2295 and then (Is_RTE
(P_Type
, RE_Exception_Id
)
2297 Is_RTE
(P_Type
, RE_Exception_Occurrence
))
2299 Check_Restriction
(No_Exception_Registration
, P
);
2302 -- Here we must check that the first argument is an access type
2303 -- that is compatible with Ada.Streams.Root_Stream_Type'Class.
2305 Analyze_And_Resolve
(E1
);
2308 -- Note: the double call to Root_Type here is needed because the
2309 -- root type of a class-wide type is the corresponding type (e.g.
2310 -- X for X'Class, and we really want to go to the root.)
2312 if not Is_Access_Type
(Etyp
)
2313 or else Root_Type
(Root_Type
(Designated_Type
(Etyp
))) /=
2314 RTE
(RE_Root_Stream_Type
)
2317 ("expected access to Ada.Streams.Root_Stream_Type''Class", E1
);
2320 -- Check that the second argument is of the right type if there is
2321 -- one (the Input attribute has only one argument so this is skipped)
2323 if Present
(E2
) then
2326 if Nam
= TSS_Stream_Read
2327 and then not Is_OK_Variable_For_Out_Formal
(E2
)
2330 ("second argument of % attribute must be a variable", E2
);
2333 Resolve
(E2
, P_Type
);
2337 end Check_Stream_Attribute
;
2339 -------------------------
2340 -- Check_System_Prefix --
2341 -------------------------
2343 procedure Check_System_Prefix
is
2345 if Nkind
(P
) /= N_Identifier
or else Chars
(P
) /= Name_System
then
2346 Error_Attr
("only allowed prefix for % attribute is System", P
);
2348 end Check_System_Prefix
;
2350 -----------------------
2351 -- Check_Task_Prefix --
2352 -----------------------
2354 procedure Check_Task_Prefix
is
2358 -- Ada 2005 (AI-345): Attribute 'Terminated can be applied to
2359 -- task interface class-wide types.
2361 if Is_Task_Type
(Etype
(P
))
2362 or else (Is_Access_Type
(Etype
(P
))
2363 and then Is_Task_Type
(Designated_Type
(Etype
(P
))))
2364 or else (Ada_Version
>= Ada_2005
2365 and then Ekind
(Etype
(P
)) = E_Class_Wide_Type
2366 and then Is_Interface
(Etype
(P
))
2367 and then Is_Task_Interface
(Etype
(P
)))
2372 if Ada_Version
>= Ada_2005
then
2374 ("prefix of % attribute must be a task or a task " &
2375 "interface class-wide object");
2378 Error_Attr_P
("prefix of % attribute must be a task");
2381 end Check_Task_Prefix
;
2387 -- The possibilities are an entity name denoting a type, or an
2388 -- attribute reference that denotes a type (Base or Class). If
2389 -- the type is incomplete, replace it with its full view.
2391 procedure Check_Type
is
2393 if not Is_Entity_Name
(P
)
2394 or else not Is_Type
(Entity
(P
))
2396 Error_Attr_P
("prefix of % attribute must be a type");
2398 elsif Is_Protected_Self_Reference
(P
) then
2400 ("prefix of % attribute denotes current instance "
2401 & "(RM 9.4(21/2))");
2403 elsif Ekind
(Entity
(P
)) = E_Incomplete_Type
2404 and then Present
(Full_View
(Entity
(P
)))
2406 P_Type
:= Full_View
(Entity
(P
));
2407 Set_Entity
(P
, P_Type
);
2411 ---------------------
2412 -- Check_Unit_Name --
2413 ---------------------
2415 procedure Check_Unit_Name
(Nod
: Node_Id
) is
2417 if Nkind
(Nod
) = N_Identifier
then
2420 elsif Nkind_In
(Nod
, N_Selected_Component
, N_Expanded_Name
) then
2421 Check_Unit_Name
(Prefix
(Nod
));
2423 if Nkind
(Selector_Name
(Nod
)) = N_Identifier
then
2428 Error_Attr
("argument for % attribute must be unit name", P
);
2429 end Check_Unit_Name
;
2435 procedure Error_Attr
is
2437 Set_Etype
(N
, Any_Type
);
2438 Set_Entity
(N
, Any_Type
);
2439 raise Bad_Attribute
;
2442 procedure Error_Attr
(Msg
: String; Error_Node
: Node_Id
) is
2444 Error_Msg_Name_1
:= Aname
;
2445 Error_Msg_N
(Msg
, Error_Node
);
2453 procedure Error_Attr_P
(Msg
: String) is
2455 Error_Msg_Name_1
:= Aname
;
2456 Error_Msg_F
(Msg
, P
);
2460 ----------------------------
2461 -- Legal_Formal_Attribute --
2462 ----------------------------
2464 procedure Legal_Formal_Attribute
is
2468 if not Is_Entity_Name
(P
)
2469 or else not Is_Type
(Entity
(P
))
2471 Error_Attr_P
("prefix of % attribute must be generic type");
2473 elsif Is_Generic_Actual_Type
(Entity
(P
))
2475 or else In_Inlined_Body
2479 elsif Is_Generic_Type
(Entity
(P
)) then
2480 if Is_Definite_Subtype
(Entity
(P
)) then
2482 ("prefix of % attribute must be indefinite generic type");
2487 ("prefix of % attribute must be indefinite generic type");
2490 Set_Etype
(N
, Standard_Boolean
);
2491 end Legal_Formal_Attribute
;
2493 ---------------------------------------------------------------
2494 -- Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements --
2495 ---------------------------------------------------------------
2497 procedure Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
is
2501 Check_Not_Incomplete_Type
;
2502 Set_Etype
(N
, Universal_Integer
);
2503 end Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
;
2509 procedure Min_Max
is
2513 Resolve
(E1
, P_Base_Type
);
2514 Resolve
(E2
, P_Base_Type
);
2515 Set_Etype
(N
, P_Base_Type
);
2517 -- Check for comparison on unordered enumeration type
2519 if Bad_Unordered_Enumeration_Reference
(N
, P_Base_Type
) then
2520 Error_Msg_Sloc
:= Sloc
(P_Base_Type
);
2522 ("comparison on unordered enumeration type& declared#?U?",
2527 ------------------------
2528 -- Standard_Attribute --
2529 ------------------------
2531 procedure Standard_Attribute
(Val
: Int
) is
2533 Check_Standard_Prefix
;
2534 Rewrite
(N
, Make_Integer_Literal
(Loc
, Val
));
2536 Set_Is_Static_Expression
(N
, True);
2537 end Standard_Attribute
;
2539 --------------------
2540 -- Uneval_Old_Msg --
2541 --------------------
2543 procedure Uneval_Old_Msg
is
2544 Uneval_Old_Setting
: Character;
2548 -- If from aspect, then Uneval_Old_Setting comes from flags in the
2549 -- N_Aspect_Specification node that corresponds to the attribute.
2551 -- First find the pragma in which we appear (note that at this stage,
2552 -- even if we appeared originally within an aspect specification, we
2553 -- are now within the corresponding pragma).
2557 Prag
:= Parent
(Prag
);
2558 exit when No
(Prag
) or else Nkind
(Prag
) = N_Pragma
;
2561 if Present
(Prag
) then
2562 if Uneval_Old_Accept
(Prag
) then
2563 Uneval_Old_Setting
:= 'A';
2564 elsif Uneval_Old_Warn
(Prag
) then
2565 Uneval_Old_Setting
:= 'W';
2567 Uneval_Old_Setting
:= 'E';
2570 -- If we did not find the pragma, that's odd, just use the setting
2571 -- from Opt.Uneval_Old. Perhaps this is due to a previous error?
2574 Uneval_Old_Setting
:= Opt
.Uneval_Old
;
2577 -- Processing depends on the setting of Uneval_Old
2579 case Uneval_Old_Setting
is
2582 ("prefix of attribute % that is potentially "
2583 & "unevaluated must denote an entity");
2586 Error_Msg_Name_1
:= Aname
;
2588 ("??prefix of attribute % appears in potentially "
2589 & "unevaluated context, exception may be raised", P
);
2595 raise Program_Error
;
2599 -------------------------
2600 -- Unexpected Argument --
2601 -------------------------
2603 procedure Unexpected_Argument
(En
: Node_Id
) is
2605 Error_Attr
("unexpected argument for % attribute", En
);
2606 end Unexpected_Argument
;
2608 -------------------------------------------------
2609 -- Validate_Non_Static_Attribute_Function_Call --
2610 -------------------------------------------------
2612 -- This function should be moved to Sem_Dist ???
2614 procedure Validate_Non_Static_Attribute_Function_Call
is
2616 if In_Preelaborated_Unit
2617 and then not In_Subprogram_Or_Concurrent_Unit
2619 Flag_Non_Static_Expr
2620 ("non-static function call in preelaborated unit!", N
);
2622 end Validate_Non_Static_Attribute_Function_Call
;
2624 -- Start of processing for Analyze_Attribute
2627 -- Immediate return if unrecognized attribute (already diagnosed
2628 -- by parser, so there is nothing more that we need to do)
2630 if not Is_Attribute_Name
(Aname
) then
2631 raise Bad_Attribute
;
2634 -- Deal with Ada 83 issues
2636 if Comes_From_Source
(N
) then
2637 if not Attribute_83
(Attr_Id
) then
2638 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
2639 Error_Msg_Name_1
:= Aname
;
2640 Error_Msg_N
("(Ada 83) attribute% is not standard??", N
);
2643 if Attribute_Impl_Def
(Attr_Id
) then
2644 Check_Restriction
(No_Implementation_Attributes
, N
);
2649 -- Deal with Ada 2005 attributes that are implementation attributes
2650 -- because they appear in a version of Ada before Ada 2005, and
2651 -- similarly for Ada 2012 attributes appearing in an earlier version.
2653 if (Attribute_05
(Attr_Id
) and then Ada_Version
< Ada_2005
)
2655 (Attribute_12
(Attr_Id
) and then Ada_Version
< Ada_2012
)
2657 Check_Restriction
(No_Implementation_Attributes
, N
);
2660 -- Remote access to subprogram type access attribute reference needs
2661 -- unanalyzed copy for tree transformation. The analyzed copy is used
2662 -- for its semantic information (whether prefix is a remote subprogram
2663 -- name), the unanalyzed copy is used to construct new subtree rooted
2664 -- with N_Aggregate which represents a fat pointer aggregate.
2666 if Aname
= Name_Access
then
2667 Discard_Node
(Copy_Separate_Tree
(N
));
2670 -- Analyze prefix and exit if error in analysis. If the prefix is an
2671 -- incomplete type, use full view if available. Note that there are
2672 -- some attributes for which we do not analyze the prefix, since the
2673 -- prefix is not a normal name, or else needs special handling.
2675 if Aname
/= Name_Elab_Body
and then
2676 Aname
/= Name_Elab_Spec
and then
2677 Aname
/= Name_Elab_Subp_Body
and then
2678 Aname
/= Name_UET_Address
and then
2679 Aname
/= Name_Enabled
and then
2683 P_Type
:= Etype
(P
);
2685 if Is_Entity_Name
(P
)
2686 and then Present
(Entity
(P
))
2687 and then Is_Type
(Entity
(P
))
2689 if Ekind
(Entity
(P
)) = E_Incomplete_Type
then
2690 P_Type
:= Get_Full_View
(P_Type
);
2691 Set_Entity
(P
, P_Type
);
2692 Set_Etype
(P
, P_Type
);
2694 elsif Entity
(P
) = Current_Scope
2695 and then Is_Record_Type
(Entity
(P
))
2697 -- Use of current instance within the type. Verify that if the
2698 -- attribute appears within a constraint, it yields an access
2699 -- type, other uses are illegal.
2707 and then Nkind
(Parent
(Par
)) /= N_Component_Definition
2709 Par
:= Parent
(Par
);
2713 and then Nkind
(Par
) = N_Subtype_Indication
2715 if Attr_Id
/= Attribute_Access
2716 and then Attr_Id
/= Attribute_Unchecked_Access
2717 and then Attr_Id
/= Attribute_Unrestricted_Access
2720 ("in a constraint the current instance can only "
2721 & "be used with an access attribute", N
);
2728 if P_Type
= Any_Type
then
2729 raise Bad_Attribute
;
2732 P_Base_Type
:= Base_Type
(P_Type
);
2735 -- Analyze expressions that may be present, exiting if an error occurs
2742 E1
:= First
(Exprs
);
2744 -- Skip analysis for case of Restriction_Set, we do not expect
2745 -- the argument to be analyzed in this case.
2747 if Aname
/= Name_Restriction_Set
then
2750 -- Check for missing/bad expression (result of previous error)
2752 if No
(E1
) or else Etype
(E1
) = Any_Type
then
2753 raise Bad_Attribute
;
2759 if Present
(E2
) then
2762 if Etype
(E2
) = Any_Type
then
2763 raise Bad_Attribute
;
2766 if Present
(Next
(E2
)) then
2767 Unexpected_Argument
(Next
(E2
));
2772 -- Cases where prefix must be resolvable by itself
2774 if Is_Overloaded
(P
)
2775 and then Aname
/= Name_Access
2776 and then Aname
/= Name_Address
2777 and then Aname
/= Name_Code_Address
2778 and then Aname
/= Name_Result
2779 and then Aname
/= Name_Unchecked_Access
2781 -- The prefix must be resolvable by itself, without reference to the
2782 -- attribute. One case that requires special handling is a prefix
2783 -- that is a function name, where one interpretation may be a
2784 -- parameterless call. Entry attributes are handled specially below.
2786 if Is_Entity_Name
(P
)
2787 and then not Nam_In
(Aname
, Name_Count
, Name_Caller
)
2789 Check_Parameterless_Call
(P
);
2792 if Is_Overloaded
(P
) then
2794 -- Ada 2005 (AI-345): Since protected and task types have
2795 -- primitive entry wrappers, the attributes Count, and Caller
2796 -- require a context check
2798 if Nam_In
(Aname
, Name_Count
, Name_Caller
) then
2800 Count
: Natural := 0;
2805 Get_First_Interp
(P
, I
, It
);
2806 while Present
(It
.Nam
) loop
2807 if Comes_From_Source
(It
.Nam
) then
2813 Get_Next_Interp
(I
, It
);
2817 Error_Attr
("ambiguous prefix for % attribute", P
);
2819 Set_Is_Overloaded
(P
, False);
2824 Error_Attr
("ambiguous prefix for % attribute", P
);
2829 -- In SPARK, attributes of private types are only allowed if the full
2830 -- type declaration is visible.
2832 -- Note: the check for Present (Entity (P)) defends against some error
2833 -- conditions where the Entity field is not set.
2835 if Is_Entity_Name
(P
) and then Present
(Entity
(P
))
2836 and then Is_Type
(Entity
(P
))
2837 and then Is_Private_Type
(P_Type
)
2838 and then not In_Open_Scopes
(Scope
(P_Type
))
2839 and then not In_Spec_Expression
2841 Check_SPARK_05_Restriction
("invisible attribute of type", N
);
2844 -- Remaining processing depends on attribute
2848 -- Attributes related to Ada 2012 iterators. Attribute specifications
2849 -- exist for these, but they cannot be queried.
2851 when Attribute_Constant_Indexing |
2852 Attribute_Default_Iterator |
2853 Attribute_Implicit_Dereference |
2854 Attribute_Iterator_Element |
2855 Attribute_Iterable |
2856 Attribute_Variable_Indexing
=>
2857 Error_Msg_N
("illegal attribute", N
);
2859 -- Internal attributes used to deal with Ada 2012 delayed aspects. These
2860 -- were already rejected by the parser. Thus they shouldn't appear here.
2862 when Internal_Attribute_Id
=>
2863 raise Program_Error
;
2869 when Attribute_Abort_Signal
=>
2870 Check_Standard_Prefix
;
2871 Rewrite
(N
, New_Occurrence_Of
(Stand
.Abort_Signal
, Loc
));
2878 when Attribute_Access
=>
2879 Analyze_Access_Attribute
;
2880 Check_Not_Incomplete_Type
;
2886 when Attribute_Address
=>
2889 Check_Not_Incomplete_Type
;
2890 Set_Etype
(N
, RTE
(RE_Address
));
2896 when Attribute_Address_Size
=>
2897 Standard_Attribute
(System_Address_Size
);
2903 when Attribute_Adjacent
=>
2904 Check_Floating_Point_Type_2
;
2905 Set_Etype
(N
, P_Base_Type
);
2906 Resolve
(E1
, P_Base_Type
);
2907 Resolve
(E2
, P_Base_Type
);
2913 when Attribute_Aft
=>
2914 Check_Fixed_Point_Type_0
;
2915 Set_Etype
(N
, Universal_Integer
);
2921 when Attribute_Alignment
=>
2923 -- Don't we need more checking here, cf Size ???
2926 Check_Not_Incomplete_Type
;
2928 Set_Etype
(N
, Universal_Integer
);
2934 when Attribute_Asm_Input
=>
2935 Check_Asm_Attribute
;
2937 -- The back-end may need to take the address of E2
2939 if Is_Entity_Name
(E2
) then
2940 Set_Address_Taken
(Entity
(E2
));
2943 Set_Etype
(N
, RTE
(RE_Asm_Input_Operand
));
2949 when Attribute_Asm_Output
=>
2950 Check_Asm_Attribute
;
2952 if Etype
(E2
) = Any_Type
then
2955 elsif Aname
= Name_Asm_Output
then
2956 if not Is_Variable
(E2
) then
2958 ("second argument for Asm_Output is not variable", E2
);
2962 Note_Possible_Modification
(E2
, Sure
=> True);
2964 -- The back-end may need to take the address of E2
2966 if Is_Entity_Name
(E2
) then
2967 Set_Address_Taken
(Entity
(E2
));
2970 Set_Etype
(N
, RTE
(RE_Asm_Output_Operand
));
2972 -----------------------------
2973 -- Atomic_Always_Lock_Free --
2974 -----------------------------
2976 when Attribute_Atomic_Always_Lock_Free
=>
2979 Set_Etype
(N
, Standard_Boolean
);
2985 -- Note: when the base attribute appears in the context of a subtype
2986 -- mark, the analysis is done by Sem_Ch8.Find_Type, rather than by
2987 -- the following circuit.
2989 when Attribute_Base
=> Base
: declare
2997 if Ada_Version
>= Ada_95
2998 and then not Is_Scalar_Type
(Typ
)
2999 and then not Is_Generic_Type
(Typ
)
3001 Error_Attr_P
("prefix of Base attribute must be scalar type");
3003 elsif Sloc
(Typ
) = Standard_Location
3004 and then Base_Type
(Typ
) = Typ
3005 and then Warn_On_Redundant_Constructs
3007 Error_Msg_NE
-- CODEFIX
3008 ("?r?redundant attribute, & is its own base type", N
, Typ
);
3011 if Nkind
(Parent
(N
)) /= N_Attribute_Reference
then
3012 Error_Msg_Name_1
:= Aname
;
3013 Check_SPARK_05_Restriction
3014 ("attribute% is only allowed as prefix of another attribute", P
);
3017 Set_Etype
(N
, Base_Type
(Entity
(P
)));
3018 Set_Entity
(N
, Base_Type
(Entity
(P
)));
3019 Rewrite
(N
, New_Occurrence_Of
(Entity
(N
), Loc
));
3027 when Attribute_Bit
=> Bit
:
3031 if not Is_Object_Reference
(P
) then
3032 Error_Attr_P
("prefix for % attribute must be object");
3034 -- What about the access object cases ???
3040 Set_Etype
(N
, Universal_Integer
);
3047 when Attribute_Bit_Order
=> Bit_Order
:
3052 if not Is_Record_Type
(P_Type
) then
3053 Error_Attr_P
("prefix of % attribute must be record type");
3056 if Bytes_Big_Endian
xor Reverse_Bit_Order
(P_Type
) then
3058 New_Occurrence_Of
(RTE
(RE_High_Order_First
), Loc
));
3061 New_Occurrence_Of
(RTE
(RE_Low_Order_First
), Loc
));
3064 Set_Etype
(N
, RTE
(RE_Bit_Order
));
3067 -- Reset incorrect indication of staticness
3069 Set_Is_Static_Expression
(N
, False);
3076 -- Note: in generated code, we can have a Bit_Position attribute
3077 -- applied to a (naked) record component (i.e. the prefix is an
3078 -- identifier that references an E_Component or E_Discriminant
3079 -- entity directly, and this is interpreted as expected by Gigi.
3080 -- The following code will not tolerate such usage, but when the
3081 -- expander creates this special case, it marks it as analyzed
3082 -- immediately and sets an appropriate type.
3084 when Attribute_Bit_Position
=>
3085 if Comes_From_Source
(N
) then
3089 Set_Etype
(N
, Universal_Integer
);
3095 when Attribute_Body_Version
=>
3098 Set_Etype
(N
, RTE
(RE_Version_String
));
3104 when Attribute_Callable
=>
3106 Set_Etype
(N
, Standard_Boolean
);
3113 when Attribute_Caller
=> Caller
: declare
3120 if Nkind_In
(P
, N_Identifier
, N_Expanded_Name
) then
3123 if not Is_Entry
(Ent
) then
3124 Error_Attr
("invalid entry name", N
);
3128 Error_Attr
("invalid entry name", N
);
3132 for J
in reverse 0 .. Scope_Stack
.Last
loop
3133 S
:= Scope_Stack
.Table
(J
).Entity
;
3135 if S
= Scope
(Ent
) then
3136 Error_Attr
("Caller must appear in matching accept or body", N
);
3142 Set_Etype
(N
, RTE
(RO_AT_Task_Id
));
3149 when Attribute_Ceiling
=>
3150 Check_Floating_Point_Type_1
;
3151 Set_Etype
(N
, P_Base_Type
);
3152 Resolve
(E1
, P_Base_Type
);
3158 when Attribute_Class
=>
3159 Check_Restriction
(No_Dispatch
, N
);
3163 -- Applying Class to untagged incomplete type is obsolescent in Ada
3164 -- 2005. Note that we can't test Is_Tagged_Type here on P_Type, since
3165 -- this flag gets set by Find_Type in this situation.
3167 if Restriction_Check_Required
(No_Obsolescent_Features
)
3168 and then Ada_Version
>= Ada_2005
3169 and then Ekind
(P_Type
) = E_Incomplete_Type
3172 DN
: constant Node_Id
:= Declaration_Node
(P_Type
);
3174 if Nkind
(DN
) = N_Incomplete_Type_Declaration
3175 and then not Tagged_Present
(DN
)
3177 Check_Restriction
(No_Obsolescent_Features
, P
);
3186 when Attribute_Code_Address
=>
3189 if Nkind
(P
) = N_Attribute_Reference
3190 and then Nam_In
(Attribute_Name
(P
), Name_Elab_Body
, Name_Elab_Spec
)
3194 elsif not Is_Entity_Name
(P
)
3195 or else (Ekind
(Entity
(P
)) /= E_Function
3197 Ekind
(Entity
(P
)) /= E_Procedure
)
3199 Error_Attr
("invalid prefix for % attribute", P
);
3200 Set_Address_Taken
(Entity
(P
));
3202 -- Issue an error if the prefix denotes an eliminated subprogram
3205 Check_For_Eliminated_Subprogram
(P
, Entity
(P
));
3208 Set_Etype
(N
, RTE
(RE_Address
));
3210 ----------------------
3211 -- Compiler_Version --
3212 ----------------------
3214 when Attribute_Compiler_Version
=>
3216 Check_Standard_Prefix
;
3217 Rewrite
(N
, Make_String_Literal
(Loc
, "GNAT " & Gnat_Version_String
));
3218 Analyze_And_Resolve
(N
, Standard_String
);
3219 Set_Is_Static_Expression
(N
, True);
3221 --------------------
3222 -- Component_Size --
3223 --------------------
3225 when Attribute_Component_Size
=>
3227 Set_Etype
(N
, Universal_Integer
);
3229 -- Note: unlike other array attributes, unconstrained arrays are OK
3231 if Is_Array_Type
(P_Type
) and then not Is_Constrained
(P_Type
) then
3241 when Attribute_Compose
=>
3242 Check_Floating_Point_Type_2
;
3243 Set_Etype
(N
, P_Base_Type
);
3244 Resolve
(E1
, P_Base_Type
);
3245 Resolve
(E2
, Any_Integer
);
3251 when Attribute_Constrained
=>
3253 Set_Etype
(N
, Standard_Boolean
);
3255 -- Case from RM J.4(2) of constrained applied to private type
3257 if Is_Entity_Name
(P
) and then Is_Type
(Entity
(P
)) then
3258 Check_Restriction
(No_Obsolescent_Features
, P
);
3260 if Warn_On_Obsolescent_Feature
then
3262 ("constrained for private type is an " &
3263 "obsolescent feature (RM J.4)?j?", N
);
3266 -- If we are within an instance, the attribute must be legal
3267 -- because it was valid in the generic unit. Ditto if this is
3268 -- an inlining of a function declared in an instance.
3270 if In_Instance
or else In_Inlined_Body
then
3273 -- For sure OK if we have a real private type itself, but must
3274 -- be completed, cannot apply Constrained to incomplete type.
3276 elsif Is_Private_Type
(Entity
(P
)) then
3278 -- Note: this is one of the Annex J features that does not
3279 -- generate a warning from -gnatwj, since in fact it seems
3280 -- very useful, and is used in the GNAT runtime.
3282 Check_Not_Incomplete_Type
;
3286 -- Normal (non-obsolescent case) of application to object of
3287 -- a discriminated type.
3290 Check_Object_Reference
(P
);
3292 -- If N does not come from source, then we allow the
3293 -- the attribute prefix to be of a private type whose
3294 -- full type has discriminants. This occurs in cases
3295 -- involving expanded calls to stream attributes.
3297 if not Comes_From_Source
(N
) then
3298 P_Type
:= Underlying_Type
(P_Type
);
3301 -- Must have discriminants or be an access type designating
3302 -- a type with discriminants. If it is a classwide type it
3303 -- has unknown discriminants.
3305 if Has_Discriminants
(P_Type
)
3306 or else Has_Unknown_Discriminants
(P_Type
)
3308 (Is_Access_Type
(P_Type
)
3309 and then Has_Discriminants
(Designated_Type
(P_Type
)))
3313 -- The rule given in 3.7.2 is part of static semantics, but the
3314 -- intent is clearly that it be treated as a legality rule, and
3315 -- rechecked in the visible part of an instance. Nevertheless
3316 -- the intent also seems to be it should legally apply to the
3317 -- actual of a formal with unknown discriminants, regardless of
3318 -- whether the actual has discriminants, in which case the value
3319 -- of the attribute is determined using the J.4 rules. This choice
3320 -- seems the most useful, and is compatible with existing tests.
3322 elsif In_Instance
then
3325 -- Also allow an object of a generic type if extensions allowed
3326 -- and allow this for any type at all. (this may be obsolete ???)
3328 elsif (Is_Generic_Type
(P_Type
)
3329 or else Is_Generic_Actual_Type
(P_Type
))
3330 and then Extensions_Allowed
3336 -- Fall through if bad prefix
3339 ("prefix of % attribute must be object of discriminated type");
3345 when Attribute_Copy_Sign
=>
3346 Check_Floating_Point_Type_2
;
3347 Set_Etype
(N
, P_Base_Type
);
3348 Resolve
(E1
, P_Base_Type
);
3349 Resolve
(E2
, P_Base_Type
);
3355 when Attribute_Count
=> Count
:
3364 if Nkind_In
(P
, N_Identifier
, N_Expanded_Name
) then
3367 if Ekind
(Ent
) /= E_Entry
then
3368 Error_Attr
("invalid entry name", N
);
3371 elsif Nkind
(P
) = N_Indexed_Component
then
3372 if not Is_Entity_Name
(Prefix
(P
))
3373 or else No
(Entity
(Prefix
(P
)))
3374 or else Ekind
(Entity
(Prefix
(P
))) /= E_Entry_Family
3376 if Nkind
(Prefix
(P
)) = N_Selected_Component
3377 and then Present
(Entity
(Selector_Name
(Prefix
(P
))))
3378 and then Ekind
(Entity
(Selector_Name
(Prefix
(P
)))) =
3382 ("attribute % must apply to entry of current task", P
);
3385 Error_Attr
("invalid entry family name", P
);
3390 Ent
:= Entity
(Prefix
(P
));
3393 elsif Nkind
(P
) = N_Selected_Component
3394 and then Present
(Entity
(Selector_Name
(P
)))
3395 and then Ekind
(Entity
(Selector_Name
(P
))) = E_Entry
3398 ("attribute % must apply to entry of current task", P
);
3401 Error_Attr
("invalid entry name", N
);
3405 for J
in reverse 0 .. Scope_Stack
.Last
loop
3406 S
:= Scope_Stack
.Table
(J
).Entity
;
3408 if S
= Scope
(Ent
) then
3409 if Nkind
(P
) = N_Expanded_Name
then
3410 Tsk
:= Entity
(Prefix
(P
));
3412 -- The prefix denotes either the task type, or else a
3413 -- single task whose task type is being analyzed.
3415 if (Is_Type
(Tsk
) and then Tsk
= S
)
3416 or else (not Is_Type
(Tsk
)
3417 and then Etype
(Tsk
) = S
3418 and then not (Comes_From_Source
(S
)))
3423 ("Attribute % must apply to entry of current task", N
);
3429 elsif Ekind
(Scope
(Ent
)) in Task_Kind
3431 not Ekind_In
(S
, E_Loop
, E_Block
, E_Entry
, E_Entry_Family
)
3433 Error_Attr
("Attribute % cannot appear in inner unit", N
);
3435 elsif Ekind
(Scope
(Ent
)) = E_Protected_Type
3436 and then not Has_Completion
(Scope
(Ent
))
3438 Error_Attr
("attribute % can only be used inside body", N
);
3442 if Is_Overloaded
(P
) then
3444 Index
: Interp_Index
;
3448 Get_First_Interp
(P
, Index
, It
);
3449 while Present
(It
.Nam
) loop
3450 if It
.Nam
= Ent
then
3453 -- Ada 2005 (AI-345): Do not consider primitive entry
3454 -- wrappers generated for task or protected types.
3456 elsif Ada_Version
>= Ada_2005
3457 and then not Comes_From_Source
(It
.Nam
)
3462 Error_Attr
("ambiguous entry name", N
);
3465 Get_Next_Interp
(Index
, It
);
3470 Set_Etype
(N
, Universal_Integer
);
3473 -----------------------
3474 -- Default_Bit_Order --
3475 -----------------------
3477 when Attribute_Default_Bit_Order
=> Default_Bit_Order
: declare
3478 Target_Default_Bit_Order
: System
.Bit_Order
;
3481 Check_Standard_Prefix
;
3483 if Bytes_Big_Endian
then
3484 Target_Default_Bit_Order
:= System
.High_Order_First
;
3486 Target_Default_Bit_Order
:= System
.Low_Order_First
;
3490 Make_Integer_Literal
(Loc
,
3491 UI_From_Int
(System
.Bit_Order
'Pos (Target_Default_Bit_Order
))));
3493 Set_Etype
(N
, Universal_Integer
);
3494 Set_Is_Static_Expression
(N
);
3495 end Default_Bit_Order
;
3497 ----------------------------------
3498 -- Default_Scalar_Storage_Order --
3499 ----------------------------------
3501 when Attribute_Default_Scalar_Storage_Order
=> Default_SSO
: declare
3502 RE_Default_SSO
: RE_Id
;
3505 Check_Standard_Prefix
;
3507 case Opt
.Default_SSO
is
3509 if Bytes_Big_Endian
then
3510 RE_Default_SSO
:= RE_High_Order_First
;
3512 RE_Default_SSO
:= RE_Low_Order_First
;
3516 RE_Default_SSO
:= RE_High_Order_First
;
3519 RE_Default_SSO
:= RE_Low_Order_First
;
3522 raise Program_Error
;
3525 Rewrite
(N
, New_Occurrence_Of
(RTE
(RE_Default_SSO
), Loc
));
3532 when Attribute_Definite
=>
3533 Legal_Formal_Attribute
;
3539 when Attribute_Delta
=>
3540 Check_Fixed_Point_Type_0
;
3541 Set_Etype
(N
, Universal_Real
);
3547 when Attribute_Denorm
=>
3548 Check_Floating_Point_Type_0
;
3549 Set_Etype
(N
, Standard_Boolean
);
3555 when Attribute_Deref
=>
3558 Resolve
(E1
, RTE
(RE_Address
));
3559 Set_Etype
(N
, P_Type
);
3561 ---------------------
3562 -- Descriptor_Size --
3563 ---------------------
3565 when Attribute_Descriptor_Size
=>
3568 if not Is_Entity_Name
(P
) or else not Is_Type
(Entity
(P
)) then
3569 Error_Attr_P
("prefix of attribute % must denote a type");
3572 Set_Etype
(N
, Universal_Integer
);
3578 when Attribute_Digits
=>
3582 if not Is_Floating_Point_Type
(P_Type
)
3583 and then not Is_Decimal_Fixed_Point_Type
(P_Type
)
3586 ("prefix of % attribute must be float or decimal type");
3589 Set_Etype
(N
, Universal_Integer
);
3595 -- Also handles processing for Elab_Spec and Elab_Subp_Body
3597 when Attribute_Elab_Body |
3598 Attribute_Elab_Spec |
3599 Attribute_Elab_Subp_Body
=>
3602 Check_Unit_Name
(P
);
3603 Set_Etype
(N
, Standard_Void_Type
);
3605 -- We have to manually call the expander in this case to get
3606 -- the necessary expansion (normally attributes that return
3607 -- entities are not expanded).
3615 -- Shares processing with Elab_Body
3621 when Attribute_Elaborated
=>
3623 Check_Unit_Name
(P
);
3624 Set_Etype
(N
, Standard_Boolean
);
3630 when Attribute_Emax
=>
3631 Check_Floating_Point_Type_0
;
3632 Set_Etype
(N
, Universal_Integer
);
3638 when Attribute_Enabled
=>
3639 Check_Either_E0_Or_E1
;
3641 if Present
(E1
) then
3642 if not Is_Entity_Name
(E1
) or else No
(Entity
(E1
)) then
3643 Error_Msg_N
("entity name expected for Enabled attribute", E1
);
3648 if Nkind
(P
) /= N_Identifier
then
3649 Error_Msg_N
("identifier expected (check name)", P
);
3650 elsif Get_Check_Id
(Chars
(P
)) = No_Check_Id
then
3651 Error_Msg_N
("& is not a recognized check name", P
);
3654 Set_Etype
(N
, Standard_Boolean
);
3660 when Attribute_Enum_Rep
=> Enum_Rep
: declare
3662 if Present
(E1
) then
3664 Check_Discrete_Type
;
3665 Resolve
(E1
, P_Base_Type
);
3668 if not Is_Entity_Name
(P
)
3669 or else (not Is_Object
(Entity
(P
))
3670 and then Ekind
(Entity
(P
)) /= E_Enumeration_Literal
)
3673 ("prefix of % attribute must be " &
3674 "discrete type/object or enum literal");
3678 Set_Etype
(N
, Universal_Integer
);
3685 when Attribute_Enum_Val
=> Enum_Val
: begin
3689 if not Is_Enumeration_Type
(P_Type
) then
3690 Error_Attr_P
("prefix of % attribute must be enumeration type");
3693 -- If the enumeration type has a standard representation, the effect
3694 -- is the same as 'Val, so rewrite the attribute as a 'Val.
3696 if not Has_Non_Standard_Rep
(P_Base_Type
) then
3698 Make_Attribute_Reference
(Loc
,
3699 Prefix
=> Relocate_Node
(Prefix
(N
)),
3700 Attribute_Name
=> Name_Val
,
3701 Expressions
=> New_List
(Relocate_Node
(E1
))));
3702 Analyze_And_Resolve
(N
, P_Base_Type
);
3704 -- Non-standard representation case (enumeration with holes)
3708 Resolve
(E1
, Any_Integer
);
3709 Set_Etype
(N
, P_Base_Type
);
3717 when Attribute_Epsilon
=>
3718 Check_Floating_Point_Type_0
;
3719 Set_Etype
(N
, Universal_Real
);
3725 when Attribute_Exponent
=>
3726 Check_Floating_Point_Type_1
;
3727 Set_Etype
(N
, Universal_Integer
);
3728 Resolve
(E1
, P_Base_Type
);
3734 when Attribute_External_Tag
=>
3738 Set_Etype
(N
, Standard_String
);
3740 if not Is_Tagged_Type
(P_Type
) then
3741 Error_Attr_P
("prefix of % attribute must be tagged");
3748 when Attribute_Fast_Math
=>
3749 Check_Standard_Prefix
;
3750 Rewrite
(N
, New_Occurrence_Of
(Boolean_Literals
(Fast_Math
), Loc
));
3756 when Attribute_First
=>
3757 Check_Array_Or_Scalar_Type
;
3758 Bad_Attribute_For_Predicate
;
3764 when Attribute_First_Bit
=>
3766 Set_Etype
(N
, Universal_Integer
);
3772 when Attribute_First_Valid
=>
3773 Check_First_Last_Valid
;
3774 Set_Etype
(N
, P_Type
);
3780 when Attribute_Fixed_Value
=>
3782 Check_Fixed_Point_Type
;
3783 Resolve
(E1
, Any_Integer
);
3784 Set_Etype
(N
, P_Base_Type
);
3790 when Attribute_Floor
=>
3791 Check_Floating_Point_Type_1
;
3792 Set_Etype
(N
, P_Base_Type
);
3793 Resolve
(E1
, P_Base_Type
);
3799 when Attribute_Fore
=>
3800 Check_Fixed_Point_Type_0
;
3801 Set_Etype
(N
, Universal_Integer
);
3807 when Attribute_Fraction
=>
3808 Check_Floating_Point_Type_1
;
3809 Set_Etype
(N
, P_Base_Type
);
3810 Resolve
(E1
, P_Base_Type
);
3816 when Attribute_From_Any
=>
3818 Check_PolyORB_Attribute
;
3819 Set_Etype
(N
, P_Base_Type
);
3821 -----------------------
3822 -- Has_Access_Values --
3823 -----------------------
3825 when Attribute_Has_Access_Values
=>
3828 Set_Etype
(N
, Standard_Boolean
);
3830 ----------------------
3831 -- Has_Same_Storage --
3832 ----------------------
3834 when Attribute_Has_Same_Storage
=>
3837 -- The arguments must be objects of any type
3839 Analyze_And_Resolve
(P
);
3840 Analyze_And_Resolve
(E1
);
3841 Check_Object_Reference
(P
);
3842 Check_Object_Reference
(E1
);
3843 Set_Etype
(N
, Standard_Boolean
);
3845 -----------------------
3846 -- Has_Tagged_Values --
3847 -----------------------
3849 when Attribute_Has_Tagged_Values
=>
3852 Set_Etype
(N
, Standard_Boolean
);
3854 -----------------------
3855 -- Has_Discriminants --
3856 -----------------------
3858 when Attribute_Has_Discriminants
=>
3859 Legal_Formal_Attribute
;
3865 when Attribute_Identity
=>
3869 if Etype
(P
) = Standard_Exception_Type
then
3870 Set_Etype
(N
, RTE
(RE_Exception_Id
));
3872 -- Ada 2005 (AI-345): Attribute 'Identity may be applied to task
3873 -- interface class-wide types.
3875 elsif Is_Task_Type
(Etype
(P
))
3876 or else (Is_Access_Type
(Etype
(P
))
3877 and then Is_Task_Type
(Designated_Type
(Etype
(P
))))
3878 or else (Ada_Version
>= Ada_2005
3879 and then Ekind
(Etype
(P
)) = E_Class_Wide_Type
3880 and then Is_Interface
(Etype
(P
))
3881 and then Is_Task_Interface
(Etype
(P
)))
3884 Set_Etype
(N
, RTE
(RO_AT_Task_Id
));
3887 if Ada_Version
>= Ada_2005
then
3889 ("prefix of % attribute must be an exception, a " &
3890 "task or a task interface class-wide object");
3893 ("prefix of % attribute must be a task or an exception");
3901 when Attribute_Image
=> Image
:
3903 Check_SPARK_05_Restriction_On_Attribute
;
3905 Set_Etype
(N
, Standard_String
);
3907 if Is_Real_Type
(P_Type
) then
3908 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
3909 Error_Msg_Name_1
:= Aname
;
3911 ("(Ada 83) % attribute not allowed for real types", N
);
3915 if Is_Enumeration_Type
(P_Type
) then
3916 Check_Restriction
(No_Enumeration_Maps
, N
);
3920 Resolve
(E1
, P_Base_Type
);
3922 Validate_Non_Static_Attribute_Function_Call
;
3924 -- Check restriction No_Fixed_IO. Note the check of Comes_From_Source
3925 -- to avoid giving a duplicate message for Img expanded into Image.
3927 if Restriction_Check_Required
(No_Fixed_IO
)
3928 and then Comes_From_Source
(N
)
3929 and then Is_Fixed_Point_Type
(P_Type
)
3931 Check_Restriction
(No_Fixed_IO
, P
);
3939 when Attribute_Img
=> Img
:
3942 Set_Etype
(N
, Standard_String
);
3944 if not Is_Scalar_Type
(P_Type
)
3945 or else (Is_Entity_Name
(P
) and then Is_Type
(Entity
(P
)))
3948 ("prefix of % attribute must be scalar object name");
3953 -- Check restriction No_Fixed_IO
3955 if Restriction_Check_Required
(No_Fixed_IO
)
3956 and then Is_Fixed_Point_Type
(P_Type
)
3958 Check_Restriction
(No_Fixed_IO
, P
);
3966 when Attribute_Input
=>
3968 Check_Stream_Attribute
(TSS_Stream_Input
);
3969 Set_Etype
(N
, P_Base_Type
);
3975 when Attribute_Integer_Value
=>
3978 Resolve
(E1
, Any_Fixed
);
3980 -- Signal an error if argument type is not a specific fixed-point
3981 -- subtype. An error has been signalled already if the argument
3982 -- was not of a fixed-point type.
3984 if Etype
(E1
) = Any_Fixed
and then not Error_Posted
(E1
) then
3985 Error_Attr
("argument of % must be of a fixed-point type", E1
);
3988 Set_Etype
(N
, P_Base_Type
);
3994 when Attribute_Invalid_Value
=>
3997 Set_Etype
(N
, P_Base_Type
);
3998 Invalid_Value_Used
:= True;
4004 when Attribute_Large
=>
4007 Set_Etype
(N
, Universal_Real
);
4013 when Attribute_Last
=>
4014 Check_Array_Or_Scalar_Type
;
4015 Bad_Attribute_For_Predicate
;
4021 when Attribute_Last_Bit
=>
4023 Set_Etype
(N
, Universal_Integer
);
4029 when Attribute_Last_Valid
=>
4030 Check_First_Last_Valid
;
4031 Set_Etype
(N
, P_Type
);
4037 when Attribute_Leading_Part
=>
4038 Check_Floating_Point_Type_2
;
4039 Set_Etype
(N
, P_Base_Type
);
4040 Resolve
(E1
, P_Base_Type
);
4041 Resolve
(E2
, Any_Integer
);
4047 when Attribute_Length
=>
4049 Set_Etype
(N
, Universal_Integer
);
4055 when Attribute_Library_Level
=>
4058 if not Is_Entity_Name
(P
) then
4059 Error_Attr_P
("prefix of % attribute must be an entity name");
4062 if not Inside_A_Generic
then
4063 Set_Boolean_Result
(N
,
4064 Is_Library_Level_Entity
(Entity
(P
)));
4067 Set_Etype
(N
, Standard_Boolean
);
4073 when Attribute_Lock_Free
=>
4075 Set_Etype
(N
, Standard_Boolean
);
4077 if not Is_Protected_Type
(P_Type
) then
4079 ("prefix of % attribute must be a protected object");
4086 when Attribute_Loop_Entry
=> Loop_Entry
: declare
4087 procedure Check_References_In_Prefix
(Loop_Id
: Entity_Id
);
4088 -- Inspect the prefix for any uses of entities declared within the
4089 -- related loop. Loop_Id denotes the loop identifier.
4091 --------------------------------
4092 -- Check_References_In_Prefix --
4093 --------------------------------
4095 procedure Check_References_In_Prefix
(Loop_Id
: Entity_Id
) is
4096 Loop_Decl
: constant Node_Id
:= Label_Construct
(Parent
(Loop_Id
));
4098 function Check_Reference
(Nod
: Node_Id
) return Traverse_Result
;
4099 -- Determine whether a reference mentions an entity declared
4100 -- within the related loop.
4102 function Declared_Within
(Nod
: Node_Id
) return Boolean;
4103 -- Determine whether Nod appears in the subtree of Loop_Decl
4105 ---------------------
4106 -- Check_Reference --
4107 ---------------------
4109 function Check_Reference
(Nod
: Node_Id
) return Traverse_Result
is
4111 if Nkind
(Nod
) = N_Identifier
4112 and then Present
(Entity
(Nod
))
4113 and then Declared_Within
(Declaration_Node
(Entity
(Nod
)))
4116 ("prefix of attribute % cannot reference local entities",
4122 end Check_Reference
;
4124 procedure Check_References
is new Traverse_Proc
(Check_Reference
);
4126 ---------------------
4127 -- Declared_Within --
4128 ---------------------
4130 function Declared_Within
(Nod
: Node_Id
) return Boolean is
4135 while Present
(Stmt
) loop
4136 if Stmt
= Loop_Decl
then
4139 -- Prevent the search from going too far
4141 elsif Is_Body_Or_Package_Declaration
(Stmt
) then
4145 Stmt
:= Parent
(Stmt
);
4149 end Declared_Within
;
4151 -- Start of processing for Check_Prefix_For_Local_References
4154 Check_References
(P
);
4155 end Check_References_In_Prefix
;
4159 Context
: constant Node_Id
:= Parent
(N
);
4161 Enclosing_Loop
: Node_Id
;
4162 Loop_Id
: Entity_Id
:= Empty
;
4165 Enclosing_Pragma
: Node_Id
:= Empty
;
4167 -- Start of processing for Loop_Entry
4172 -- Set the type of the attribute now to ensure the successfull
4173 -- continuation of analysis even if the attribute is misplaced.
4175 Set_Etype
(Attr
, P_Type
);
4177 -- Attribute 'Loop_Entry may appear in several flavors:
4179 -- * Prefix'Loop_Entry - in this form, the attribute applies to the
4180 -- nearest enclosing loop.
4182 -- * Prefix'Loop_Entry (Expr) - depending on what Expr denotes, the
4183 -- attribute may be related to a loop denoted by label Expr or
4184 -- the prefix may denote an array object and Expr may act as an
4185 -- indexed component.
4187 -- * Prefix'Loop_Entry (Expr1, ..., ExprN) - the attribute applies
4188 -- to the nearest enclosing loop, all expressions are part of
4189 -- an indexed component.
4191 -- * Prefix'Loop_Entry (Expr) (...) (...) - depending on what Expr
4192 -- denotes, the attribute may be related to a loop denoted by
4193 -- label Expr or the prefix may denote a multidimensional array
4194 -- array object and Expr along with the rest of the expressions
4195 -- may act as indexed components.
4197 -- Regardless of variations, the attribute reference does not have an
4198 -- expression list. Instead, all available expressions are stored as
4199 -- indexed components.
4201 -- When the attribute is part of an indexed component, find the first
4202 -- expression as it will determine the semantics of 'Loop_Entry.
4204 if Nkind
(Context
) = N_Indexed_Component
then
4205 E1
:= First
(Expressions
(Context
));
4208 -- The attribute reference appears in the following form:
4210 -- Prefix'Loop_Entry (Exp1, Expr2, ..., ExprN) [(...)]
4212 -- In this case, the loop name is omitted and no rewriting is
4215 if Present
(E2
) then
4218 -- The form of the attribute is:
4220 -- Prefix'Loop_Entry (Expr) [(...)]
4222 -- If Expr denotes a loop entry, the whole attribute and indexed
4223 -- component will have to be rewritten to reflect this relation.
4226 pragma Assert
(Present
(E1
));
4228 -- Do not expand the expression as it may have side effects.
4229 -- Simply preanalyze to determine whether it is a loop name or
4232 Preanalyze_And_Resolve
(E1
);
4234 if Is_Entity_Name
(E1
)
4235 and then Present
(Entity
(E1
))
4236 and then Ekind
(Entity
(E1
)) = E_Loop
4238 Loop_Id
:= Entity
(E1
);
4240 -- Transform the attribute and enclosing indexed component
4242 Set_Expressions
(N
, Expressions
(Context
));
4243 Rewrite
(Context
, N
);
4244 Set_Etype
(Context
, P_Type
);
4251 -- The prefix must denote an object
4253 if not Is_Object_Reference
(P
) then
4254 Error_Attr_P
("prefix of attribute % must denote an object");
4257 -- The prefix cannot be of a limited type because the expansion of
4258 -- Loop_Entry must create a constant initialized by the evaluated
4261 if Is_Limited_View
(Etype
(P
)) then
4262 Error_Attr_P
("prefix of attribute % cannot be limited");
4265 -- Climb the parent chain to verify the location of the attribute and
4266 -- find the enclosing loop.
4269 while Present
(Stmt
) loop
4271 -- Locate the corresponding enclosing pragma. Note that in the
4272 -- case of Assert[And_Cut] and Assume, we have already checked
4273 -- that the pragma appears in an appropriate loop location.
4275 if Nkind
(Original_Node
(Stmt
)) = N_Pragma
4276 and then Nam_In
(Pragma_Name
(Original_Node
(Stmt
)),
4277 Name_Loop_Invariant
,
4280 Name_Assert_And_Cut
,
4283 Enclosing_Pragma
:= Original_Node
(Stmt
);
4285 -- Locate the enclosing loop (if any). Note that Ada 2012 array
4286 -- iteration may be expanded into several nested loops, we are
4287 -- interested in the outermost one which has the loop identifier.
4289 elsif Nkind
(Stmt
) = N_Loop_Statement
4290 and then Present
(Identifier
(Stmt
))
4292 Enclosing_Loop
:= Stmt
;
4294 -- The original attribute reference may lack a loop name. Use
4295 -- the name of the enclosing loop because it is the related
4298 if No
(Loop_Id
) then
4299 Loop_Id
:= Entity
(Identifier
(Enclosing_Loop
));
4304 -- Prevent the search from going too far
4306 elsif Is_Body_Or_Package_Declaration
(Stmt
) then
4310 Stmt
:= Parent
(Stmt
);
4313 -- Loop_Entry must appear within a Loop_Assertion pragma (Assert,
4314 -- Assert_And_Cut, Assume count as loop assertion pragmas for this
4315 -- purpose if they appear in an appropriate location in a loop,
4316 -- which was already checked by the top level pragma circuit).
4318 if No
(Enclosing_Pragma
) then
4319 Error_Attr
("attribute% must appear within appropriate pragma", N
);
4322 -- A Loop_Entry that applies to a given loop statement must not
4323 -- appear within a body of accept statement, if this construct is
4324 -- itself enclosed by the given loop statement.
4326 for Index
in reverse 0 .. Scope_Stack
.Last
loop
4327 Scop
:= Scope_Stack
.Table
(Index
).Entity
;
4329 if Ekind
(Scop
) = E_Loop
and then Scop
= Loop_Id
then
4331 elsif Ekind_In
(Scop
, E_Block
, E_Loop
, E_Return_Statement
) then
4335 ("attribute % cannot appear in body or accept statement", N
);
4340 -- The prefix cannot mention entities declared within the related
4341 -- loop because they will not be visible once the prefix is moved
4342 -- outside the loop.
4344 Check_References_In_Prefix
(Loop_Id
);
4346 -- The prefix must denote a static entity if the pragma does not
4347 -- apply to the innermost enclosing loop statement, or if it appears
4348 -- within a potentially unevaluated epxression.
4350 if Is_Entity_Name
(P
)
4351 or else Nkind
(Parent
(P
)) = N_Object_Renaming_Declaration
4355 elsif Present
(Enclosing_Loop
)
4356 and then Entity
(Identifier
(Enclosing_Loop
)) /= Loop_Id
4359 ("prefix of attribute % that applies to outer loop must denote "
4362 elsif Is_Potentially_Unevaluated
(P
) then
4366 -- Replace the Loop_Entry attribute reference by its prefix if the
4367 -- related pragma is ignored. This transformation is OK with respect
4368 -- to typing because Loop_Entry's type is that of its prefix. This
4369 -- early transformation also avoids the generation of a useless loop
4372 if Is_Ignored
(Enclosing_Pragma
) then
4373 Rewrite
(N
, Relocate_Node
(P
));
4376 Preanalyze_And_Resolve
(P
);
4383 when Attribute_Machine
=>
4384 Check_Floating_Point_Type_1
;
4385 Set_Etype
(N
, P_Base_Type
);
4386 Resolve
(E1
, P_Base_Type
);
4392 when Attribute_Machine_Emax
=>
4393 Check_Floating_Point_Type_0
;
4394 Set_Etype
(N
, Universal_Integer
);
4400 when Attribute_Machine_Emin
=>
4401 Check_Floating_Point_Type_0
;
4402 Set_Etype
(N
, Universal_Integer
);
4404 ----------------------
4405 -- Machine_Mantissa --
4406 ----------------------
4408 when Attribute_Machine_Mantissa
=>
4409 Check_Floating_Point_Type_0
;
4410 Set_Etype
(N
, Universal_Integer
);
4412 -----------------------
4413 -- Machine_Overflows --
4414 -----------------------
4416 when Attribute_Machine_Overflows
=>
4419 Set_Etype
(N
, Standard_Boolean
);
4425 when Attribute_Machine_Radix
=>
4428 Set_Etype
(N
, Universal_Integer
);
4430 ----------------------
4431 -- Machine_Rounding --
4432 ----------------------
4434 when Attribute_Machine_Rounding
=>
4435 Check_Floating_Point_Type_1
;
4436 Set_Etype
(N
, P_Base_Type
);
4437 Resolve
(E1
, P_Base_Type
);
4439 --------------------
4440 -- Machine_Rounds --
4441 --------------------
4443 when Attribute_Machine_Rounds
=>
4446 Set_Etype
(N
, Standard_Boolean
);
4452 when Attribute_Machine_Size
=>
4455 Check_Not_Incomplete_Type
;
4456 Set_Etype
(N
, Universal_Integer
);
4462 when Attribute_Mantissa
=>
4465 Set_Etype
(N
, Universal_Integer
);
4471 when Attribute_Max
=>
4474 ----------------------------------
4475 -- Max_Alignment_For_Allocation --
4476 ----------------------------------
4478 when Attribute_Max_Size_In_Storage_Elements
=>
4479 Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
;
4481 ----------------------------------
4482 -- Max_Size_In_Storage_Elements --
4483 ----------------------------------
4485 when Attribute_Max_Alignment_For_Allocation
=>
4486 Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
;
4488 -----------------------
4489 -- Maximum_Alignment --
4490 -----------------------
4492 when Attribute_Maximum_Alignment
=>
4493 Standard_Attribute
(Ttypes
.Maximum_Alignment
);
4495 --------------------
4496 -- Mechanism_Code --
4497 --------------------
4499 when Attribute_Mechanism_Code
=>
4500 if not Is_Entity_Name
(P
)
4501 or else not Is_Subprogram
(Entity
(P
))
4503 Error_Attr_P
("prefix of % attribute must be subprogram");
4506 Check_Either_E0_Or_E1
;
4508 if Present
(E1
) then
4509 Resolve
(E1
, Any_Integer
);
4510 Set_Etype
(E1
, Standard_Integer
);
4512 if not Is_OK_Static_Expression
(E1
) then
4513 Flag_Non_Static_Expr
4514 ("expression for parameter number must be static!", E1
);
4517 elsif UI_To_Int
(Intval
(E1
)) > Number_Formals
(Entity
(P
))
4518 or else UI_To_Int
(Intval
(E1
)) < 0
4520 Error_Attr
("invalid parameter number for % attribute", E1
);
4524 Set_Etype
(N
, Universal_Integer
);
4530 when Attribute_Min
=>
4537 when Attribute_Mod
=>
4539 -- Note: this attribute is only allowed in Ada 2005 mode, but
4540 -- we do not need to test that here, since Mod is only recognized
4541 -- as an attribute name in Ada 2005 mode during the parse.
4544 Check_Modular_Integer_Type
;
4545 Resolve
(E1
, Any_Integer
);
4546 Set_Etype
(N
, P_Base_Type
);
4552 when Attribute_Model
=>
4553 Check_Floating_Point_Type_1
;
4554 Set_Etype
(N
, P_Base_Type
);
4555 Resolve
(E1
, P_Base_Type
);
4561 when Attribute_Model_Emin
=>
4562 Check_Floating_Point_Type_0
;
4563 Set_Etype
(N
, Universal_Integer
);
4569 when Attribute_Model_Epsilon
=>
4570 Check_Floating_Point_Type_0
;
4571 Set_Etype
(N
, Universal_Real
);
4573 --------------------
4574 -- Model_Mantissa --
4575 --------------------
4577 when Attribute_Model_Mantissa
=>
4578 Check_Floating_Point_Type_0
;
4579 Set_Etype
(N
, Universal_Integer
);
4585 when Attribute_Model_Small
=>
4586 Check_Floating_Point_Type_0
;
4587 Set_Etype
(N
, Universal_Real
);
4593 when Attribute_Modulus
=>
4595 Check_Modular_Integer_Type
;
4596 Set_Etype
(N
, Universal_Integer
);
4598 --------------------
4599 -- Null_Parameter --
4600 --------------------
4602 when Attribute_Null_Parameter
=> Null_Parameter
: declare
4603 Parnt
: constant Node_Id
:= Parent
(N
);
4604 GParnt
: constant Node_Id
:= Parent
(Parnt
);
4606 procedure Bad_Null_Parameter
(Msg
: String);
4607 -- Used if bad Null parameter attribute node is found. Issues
4608 -- given error message, and also sets the type to Any_Type to
4609 -- avoid blowups later on from dealing with a junk node.
4611 procedure Must_Be_Imported
(Proc_Ent
: Entity_Id
);
4612 -- Called to check that Proc_Ent is imported subprogram
4614 ------------------------
4615 -- Bad_Null_Parameter --
4616 ------------------------
4618 procedure Bad_Null_Parameter
(Msg
: String) is
4620 Error_Msg_N
(Msg
, N
);
4621 Set_Etype
(N
, Any_Type
);
4622 end Bad_Null_Parameter
;
4624 ----------------------
4625 -- Must_Be_Imported --
4626 ----------------------
4628 procedure Must_Be_Imported
(Proc_Ent
: Entity_Id
) is
4629 Pent
: constant Entity_Id
:= Ultimate_Alias
(Proc_Ent
);
4632 -- Ignore check if procedure not frozen yet (we will get
4633 -- another chance when the default parameter is reanalyzed)
4635 if not Is_Frozen
(Pent
) then
4638 elsif not Is_Imported
(Pent
) then
4640 ("Null_Parameter can only be used with imported subprogram");
4645 end Must_Be_Imported
;
4647 -- Start of processing for Null_Parameter
4652 Set_Etype
(N
, P_Type
);
4654 -- Case of attribute used as default expression
4656 if Nkind
(Parnt
) = N_Parameter_Specification
then
4657 Must_Be_Imported
(Defining_Entity
(GParnt
));
4659 -- Case of attribute used as actual for subprogram (positional)
4661 elsif Nkind
(Parnt
) in N_Subprogram_Call
4662 and then Is_Entity_Name
(Name
(Parnt
))
4664 Must_Be_Imported
(Entity
(Name
(Parnt
)));
4666 -- Case of attribute used as actual for subprogram (named)
4668 elsif Nkind
(Parnt
) = N_Parameter_Association
4669 and then Nkind
(GParnt
) in N_Subprogram_Call
4670 and then Is_Entity_Name
(Name
(GParnt
))
4672 Must_Be_Imported
(Entity
(Name
(GParnt
)));
4674 -- Not an allowed case
4678 ("Null_Parameter must be actual or default parameter");
4686 when Attribute_Object_Size
=>
4689 Check_Not_Incomplete_Type
;
4690 Set_Etype
(N
, Universal_Integer
);
4696 when Attribute_Old
=> Old
: declare
4697 procedure Check_References_In_Prefix
(Subp_Id
: Entity_Id
);
4698 -- Inspect the contents of the prefix and detect illegal uses of a
4699 -- nested 'Old, attribute 'Result or a use of an entity declared in
4700 -- the related postcondition expression. Subp_Id is the subprogram to
4701 -- which the related postcondition applies.
4703 --------------------------------
4704 -- Check_References_In_Prefix --
4705 --------------------------------
4707 procedure Check_References_In_Prefix
(Subp_Id
: Entity_Id
) is
4708 function Check_Reference
(Nod
: Node_Id
) return Traverse_Result
;
4709 -- Detect attribute 'Old, attribute 'Result of a use of an entity
4710 -- and perform the appropriate semantic check.
4712 ---------------------
4713 -- Check_Reference --
4714 ---------------------
4716 function Check_Reference
(Nod
: Node_Id
) return Traverse_Result
is
4718 -- Attributes 'Old and 'Result cannot appear in the prefix of
4719 -- another attribute 'Old.
4721 if Nkind
(Nod
) = N_Attribute_Reference
4722 and then Nam_In
(Attribute_Name
(Nod
), Name_Old
,
4725 Error_Msg_Name_1
:= Attribute_Name
(Nod
);
4726 Error_Msg_Name_2
:= Name_Old
;
4728 ("attribute % cannot appear in the prefix of attribute %",
4732 -- Entities mentioned within the prefix of attribute 'Old must
4733 -- be global to the related postcondition. If this is not the
4734 -- case, then the scope of the local entity is nested within
4735 -- that of the subprogram.
4737 elsif Is_Entity_Name
(Nod
)
4738 and then Present
(Entity
(Nod
))
4739 and then Scope_Within
(Scope
(Entity
(Nod
)), Subp_Id
)
4742 ("prefix of attribute % cannot reference local entities",
4746 -- Otherwise keep inspecting the prefix
4751 end Check_Reference
;
4753 procedure Check_References
is new Traverse_Proc
(Check_Reference
);
4755 -- Start of processing for Check_References_In_Prefix
4758 Check_References
(P
);
4759 end Check_References_In_Prefix
;
4764 Pref_Id
: Entity_Id
;
4765 Pref_Typ
: Entity_Id
;
4766 Spec_Id
: Entity_Id
;
4768 -- Start of processing for Old
4771 -- The attribute reference is a primary. If any expressions follow,
4772 -- then the attribute reference is an indexable object. Transform the
4773 -- attribute into an indexed component and analyze it.
4775 if Present
(E1
) then
4777 Make_Indexed_Component
(Loc
,
4779 Make_Attribute_Reference
(Loc
,
4780 Prefix
=> Relocate_Node
(P
),
4781 Attribute_Name
=> Name_Old
),
4782 Expressions
=> Expressions
(N
)));
4787 Analyze_Attribute_Old_Result
(Legal
, Spec_Id
);
4789 -- The aspect or pragma where attribute 'Old resides should be
4790 -- associated with a subprogram declaration or a body. If this is not
4791 -- the case, then the aspect or pragma is illegal. Return as analysis
4792 -- cannot be carried out.
4798 -- The prefix must be preanalyzed as the full analysis will take
4799 -- place during expansion.
4801 Preanalyze_And_Resolve
(P
);
4803 -- Ensure that the prefix does not contain attributes 'Old or 'Result
4805 Check_References_In_Prefix
(Spec_Id
);
4807 -- Set the type of the attribute now to prevent cascaded errors
4809 Pref_Typ
:= Etype
(P
);
4810 Set_Etype
(N
, Pref_Typ
);
4814 if Is_Limited_Type
(Pref_Typ
) then
4815 Error_Attr
("attribute % cannot apply to limited objects", P
);
4818 -- The prefix is a simple name
4820 if Is_Entity_Name
(P
) and then Present
(Entity
(P
)) then
4821 Pref_Id
:= Entity
(P
);
4823 -- Emit a warning when the prefix is a constant. Note that the use
4824 -- of Error_Attr would reset the type of N to Any_Type even though
4825 -- this is a warning. Use Error_Msg_XXX instead.
4827 if Is_Constant_Object
(Pref_Id
) then
4828 Error_Msg_Name_1
:= Name_Old
;
4830 ("??attribute % applied to constant has no effect", P
);
4833 -- Otherwise the prefix is not a simple name
4836 -- Ensure that the prefix of attribute 'Old is an entity when it
4837 -- is potentially unevaluated (6.1.1 (27/3)).
4839 if Is_Potentially_Unevaluated
(N
) then
4842 -- Detect a possible infinite recursion when the prefix denotes
4843 -- the related function.
4845 -- function Func (...) return ...
4846 -- with Post => Func'Old ...;
4848 elsif Nkind
(P
) = N_Function_Call
then
4849 Pref_Id
:= Entity
(Name
(P
));
4851 if Ekind_In
(Spec_Id
, E_Function
, E_Generic_Function
)
4852 and then Pref_Id
= Spec_Id
4854 Error_Msg_Warn
:= SPARK_Mode
/= On
;
4855 Error_Msg_N
("!possible infinite recursion<<", P
);
4856 Error_Msg_N
("\!??Storage_Error ]<<", P
);
4860 -- The prefix of attribute 'Old may refer to a component of a
4861 -- formal parameter. In this case its expansion may generate
4862 -- actual subtypes that are referenced in an inner context and
4863 -- that must be elaborated within the subprogram itself. If the
4864 -- prefix includes a function call, it may involve finalization
4865 -- actions that should be inserted when the attribute has been
4866 -- rewritten as a declaration. Create a declaration for the prefix
4867 -- and insert it at the start of the enclosing subprogram. This is
4868 -- an expansion activity that has to be performed now to prevent
4869 -- out-of-order issues.
4871 -- This expansion is both harmful and not needed in SPARK mode,
4872 -- since the formal verification backend relies on the types of
4873 -- nodes (hence is not robust w.r.t. a change to base type here),
4874 -- and does not suffer from the out-of-order issue described
4875 -- above. Thus, this expansion is skipped in SPARK mode.
4877 if not GNATprove_Mode
then
4878 Pref_Typ
:= Base_Type
(Pref_Typ
);
4879 Set_Etype
(N
, Pref_Typ
);
4880 Set_Etype
(P
, Pref_Typ
);
4882 Analyze_Dimension
(N
);
4888 ----------------------
4889 -- Overlaps_Storage --
4890 ----------------------
4892 when Attribute_Overlaps_Storage
=>
4895 -- Both arguments must be objects of any type
4897 Analyze_And_Resolve
(P
);
4898 Analyze_And_Resolve
(E1
);
4899 Check_Object_Reference
(P
);
4900 Check_Object_Reference
(E1
);
4901 Set_Etype
(N
, Standard_Boolean
);
4907 when Attribute_Output
=>
4909 Check_Stream_Attribute
(TSS_Stream_Output
);
4910 Set_Etype
(N
, Standard_Void_Type
);
4911 Resolve
(N
, Standard_Void_Type
);
4917 when Attribute_Partition_ID
=> Partition_Id
:
4921 if P_Type
/= Any_Type
then
4922 if not Is_Library_Level_Entity
(Entity
(P
)) then
4924 ("prefix of % attribute must be library-level entity");
4926 -- The defining entity of prefix should not be declared inside a
4927 -- Pure unit. RM E.1(8). Is_Pure was set during declaration.
4929 elsif Is_Entity_Name
(P
)
4930 and then Is_Pure
(Entity
(P
))
4932 Error_Attr_P
("prefix of% attribute must not be declared pure");
4936 Set_Etype
(N
, Universal_Integer
);
4939 -------------------------
4940 -- Passed_By_Reference --
4941 -------------------------
4943 when Attribute_Passed_By_Reference
=>
4946 Set_Etype
(N
, Standard_Boolean
);
4952 when Attribute_Pool_Address
=>
4954 Set_Etype
(N
, RTE
(RE_Address
));
4960 when Attribute_Pos
=>
4961 Check_Discrete_Type
;
4964 if Is_Boolean_Type
(P_Type
) then
4965 Error_Msg_Name_1
:= Aname
;
4966 Error_Msg_Name_2
:= Chars
(P_Type
);
4967 Check_SPARK_05_Restriction
4968 ("attribute% is not allowed for type%", P
);
4971 Resolve
(E1
, P_Base_Type
);
4972 Set_Etype
(N
, Universal_Integer
);
4978 when Attribute_Position
=>
4980 Set_Etype
(N
, Universal_Integer
);
4986 when Attribute_Pred
=>
4990 if Is_Real_Type
(P_Type
) or else Is_Boolean_Type
(P_Type
) then
4991 Error_Msg_Name_1
:= Aname
;
4992 Error_Msg_Name_2
:= Chars
(P_Type
);
4993 Check_SPARK_05_Restriction
4994 ("attribute% is not allowed for type%", P
);
4997 Resolve
(E1
, P_Base_Type
);
4998 Set_Etype
(N
, P_Base_Type
);
5000 -- Since Pred works on the base type, we normally do no check for the
5001 -- floating-point case, since the base type is unconstrained. But we
5002 -- make an exception in Check_Float_Overflow mode.
5004 if Is_Floating_Point_Type
(P_Type
) then
5005 if not Range_Checks_Suppressed
(P_Base_Type
) then
5006 Set_Do_Range_Check
(E1
);
5009 -- If not modular type, test for overflow check required
5012 if not Is_Modular_Integer_Type
(P_Type
)
5013 and then not Range_Checks_Suppressed
(P_Base_Type
)
5015 Enable_Range_Check
(E1
);
5023 -- Ada 2005 (AI-327): Dynamic ceiling priorities
5025 when Attribute_Priority
=>
5026 if Ada_Version
< Ada_2005
then
5027 Error_Attr
("% attribute is allowed only in Ada 2005 mode", P
);
5032 -- The prefix must be a protected object (AARM D.5.2 (2/2))
5036 if Is_Protected_Type
(Etype
(P
))
5037 or else (Is_Access_Type
(Etype
(P
))
5038 and then Is_Protected_Type
(Designated_Type
(Etype
(P
))))
5040 Resolve
(P
, Etype
(P
));
5042 Error_Attr_P
("prefix of % attribute must be a protected object");
5045 Set_Etype
(N
, Standard_Integer
);
5047 -- Must be called from within a protected procedure or entry of the
5048 -- protected object.
5055 while S
/= Etype
(P
)
5056 and then S
/= Standard_Standard
5061 if S
= Standard_Standard
then
5062 Error_Attr
("the attribute % is only allowed inside protected "
5067 Validate_Non_Static_Attribute_Function_Call
;
5073 when Attribute_Range
=>
5074 Check_Array_Or_Scalar_Type
;
5075 Bad_Attribute_For_Predicate
;
5077 if Ada_Version
= Ada_83
5078 and then Is_Scalar_Type
(P_Type
)
5079 and then Comes_From_Source
(N
)
5082 ("(Ada 83) % attribute not allowed for scalar type", P
);
5089 when Attribute_Result
=> Result
: declare
5090 function Denote_Same_Function
5091 (Pref_Id
: Entity_Id
;
5092 Spec_Id
: Entity_Id
) return Boolean;
5093 -- Determine whether the entity of the prefix Pref_Id denotes the
5094 -- same entity as that of the related subprogram Spec_Id.
5096 --------------------------
5097 -- Denote_Same_Function --
5098 --------------------------
5100 function Denote_Same_Function
5101 (Pref_Id
: Entity_Id
;
5102 Spec_Id
: Entity_Id
) return Boolean
5104 Subp_Spec
: constant Node_Id
:= Parent
(Spec_Id
);
5107 -- The prefix denotes the related subprogram
5109 if Pref_Id
= Spec_Id
then
5112 -- Account for a special case when attribute 'Result appears in
5113 -- the postcondition of a generic function.
5116 -- function Gen_Func return ...
5117 -- with Post => Gen_Func'Result ...;
5119 -- When the generic function is instantiated, the Chars field of
5120 -- the instantiated prefix still denotes the name of the generic
5121 -- function. Note that any preemptive transformation is impossible
5122 -- without a proper analysis. The structure of the wrapper package
5125 -- package Anon_Gen_Pack is
5126 -- <subtypes and renamings>
5127 -- function Subp_Decl return ...; -- (!)
5128 -- pragma Postcondition (Gen_Func'Result ...); -- (!)
5129 -- function Gen_Func ... renames Subp_Decl;
5130 -- end Anon_Gen_Pack;
5132 elsif Nkind
(Subp_Spec
) = N_Function_Specification
5133 and then Present
(Generic_Parent
(Subp_Spec
))
5134 and then Ekind_In
(Pref_Id
, E_Generic_Function
, E_Function
)
5136 if Generic_Parent
(Subp_Spec
) = Pref_Id
then
5139 elsif Present
(Alias
(Pref_Id
))
5140 and then Alias
(Pref_Id
) = Spec_Id
5146 -- Otherwise the prefix does not denote the related subprogram
5149 end Denote_Same_Function
;
5154 Pref_Id
: Entity_Id
;
5155 Spec_Id
: Entity_Id
;
5157 -- Start of processing for Result
5160 -- The attribute reference is a primary. If any expressions follow,
5161 -- then the attribute reference is an indexable object. Transform the
5162 -- attribute into an indexed component and analyze it.
5164 if Present
(E1
) then
5166 Make_Indexed_Component
(Loc
,
5168 Make_Attribute_Reference
(Loc
,
5169 Prefix
=> Relocate_Node
(P
),
5170 Attribute_Name
=> Name_Result
),
5171 Expressions
=> Expressions
(N
)));
5176 Analyze_Attribute_Old_Result
(Legal
, Spec_Id
);
5178 -- The aspect or pragma where attribute 'Result resides should be
5179 -- associated with a subprogram declaration or a body. If this is not
5180 -- the case, then the aspect or pragma is illegal. Return as analysis
5181 -- cannot be carried out.
5187 -- Attribute 'Result is part of a _Postconditions procedure. There is
5188 -- no need to perform the semantic checks below as they were already
5189 -- verified when the attribute was analyzed in its original context.
5190 -- Instead, rewrite the attribute as a reference to formal parameter
5191 -- _Result of the _Postconditions procedure.
5193 if Chars
(Spec_Id
) = Name_uPostconditions
then
5194 Rewrite
(N
, Make_Identifier
(Loc
, Name_uResult
));
5196 -- The type of formal parameter _Result is that of the function
5197 -- encapsulating the _Postconditions procedure. Resolution must
5198 -- be carried out against the function return type.
5200 Analyze_And_Resolve
(N
, Etype
(Scope
(Spec_Id
)));
5202 -- Otherwise attribute 'Result appears in its original context and
5203 -- all semantic checks should be carried out.
5206 -- Verify the legality of the prefix. It must denotes the entity
5207 -- of the related [generic] function.
5209 if Is_Entity_Name
(P
) then
5210 Pref_Id
:= Entity
(P
);
5212 if Ekind_In
(Pref_Id
, E_Function
, E_Generic_Function
) then
5213 if Denote_Same_Function
(Pref_Id
, Spec_Id
) then
5215 -- Correct the prefix of the attribute when the context
5216 -- is a generic function.
5218 if Pref_Id
/= Spec_Id
then
5219 Rewrite
(P
, New_Occurrence_Of
(Spec_Id
, Loc
));
5223 Set_Etype
(N
, Etype
(Spec_Id
));
5225 -- Otherwise the prefix denotes some unrelated function
5228 Error_Msg_Name_2
:= Chars
(Spec_Id
);
5230 ("incorrect prefix for attribute %, expected %", P
);
5233 -- Otherwise the prefix denotes some other form of subprogram
5238 ("attribute % can only appear in postcondition of "
5242 -- Otherwise the prefix is illegal
5245 Error_Msg_Name_2
:= Chars
(Spec_Id
);
5246 Error_Attr
("incorrect prefix for attribute %, expected %", P
);
5255 when Attribute_Range_Length
=>
5257 Check_Discrete_Type
;
5258 Set_Etype
(N
, Universal_Integer
);
5264 when Attribute_Read
=>
5266 Check_Stream_Attribute
(TSS_Stream_Read
);
5267 Set_Etype
(N
, Standard_Void_Type
);
5268 Resolve
(N
, Standard_Void_Type
);
5269 Note_Possible_Modification
(E2
, Sure
=> True);
5275 when Attribute_Ref
=>
5279 if Nkind
(P
) /= N_Expanded_Name
5280 or else not Is_RTE
(P_Type
, RE_Address
)
5282 Error_Attr_P
("prefix of % attribute must be System.Address");
5285 Analyze_And_Resolve
(E1
, Any_Integer
);
5286 Set_Etype
(N
, RTE
(RE_Address
));
5292 when Attribute_Remainder
=>
5293 Check_Floating_Point_Type_2
;
5294 Set_Etype
(N
, P_Base_Type
);
5295 Resolve
(E1
, P_Base_Type
);
5296 Resolve
(E2
, P_Base_Type
);
5298 ---------------------
5299 -- Restriction_Set --
5300 ---------------------
5302 when Attribute_Restriction_Set
=> Restriction_Set
: declare
5305 Unam
: Unit_Name_Type
;
5310 Check_System_Prefix
;
5312 -- No_Dependence case
5314 if Nkind
(E1
) = N_Parameter_Association
then
5315 pragma Assert
(Chars
(Selector_Name
(E1
)) = Name_No_Dependence
);
5316 U
:= Explicit_Actual_Parameter
(E1
);
5318 if not OK_No_Dependence_Unit_Name
(U
) then
5319 Set_Boolean_Result
(N
, False);
5323 -- See if there is an entry already in the table. That's the
5324 -- case in which we can return True.
5326 for J
in No_Dependences
.First
.. No_Dependences
.Last
loop
5327 if Designate_Same_Unit
(U
, No_Dependences
.Table
(J
).Unit
)
5328 and then No_Dependences
.Table
(J
).Warn
= False
5330 Set_Boolean_Result
(N
, True);
5335 -- If not in the No_Dependence table, result is False
5337 Set_Boolean_Result
(N
, False);
5339 -- In this case, we must ensure that the binder will reject any
5340 -- other unit in the partition that sets No_Dependence for this
5341 -- unit. We do that by making an entry in the special table kept
5342 -- for this purpose (if the entry is not there already).
5344 Unam
:= Get_Spec_Name
(Get_Unit_Name
(U
));
5346 for J
in Restriction_Set_Dependences
.First
..
5347 Restriction_Set_Dependences
.Last
5349 if Restriction_Set_Dependences
.Table
(J
) = Unam
then
5354 Restriction_Set_Dependences
.Append
(Unam
);
5356 -- Normal restriction case
5359 if Nkind
(E1
) /= N_Identifier
then
5360 Set_Boolean_Result
(N
, False);
5361 Error_Attr
("attribute % requires restriction identifier", E1
);
5364 R
:= Get_Restriction_Id
(Process_Restriction_Synonyms
(E1
));
5366 if R
= Not_A_Restriction_Id
then
5367 Set_Boolean_Result
(N
, False);
5368 Error_Msg_Node_1
:= E1
;
5369 Error_Attr
("invalid restriction identifier &", E1
);
5371 elsif R
not in Partition_Boolean_Restrictions
then
5372 Set_Boolean_Result
(N
, False);
5373 Error_Msg_Node_1
:= E1
;
5375 ("& is not a boolean partition-wide restriction", E1
);
5378 if Restriction_Active
(R
) then
5379 Set_Boolean_Result
(N
, True);
5381 Check_Restriction
(R
, N
);
5382 Set_Boolean_Result
(N
, False);
5386 end Restriction_Set
;
5392 when Attribute_Round
=>
5394 Check_Decimal_Fixed_Point_Type
;
5395 Set_Etype
(N
, P_Base_Type
);
5397 -- Because the context is universal_real (3.5.10(12)) it is a
5398 -- legal context for a universal fixed expression. This is the
5399 -- only attribute whose functional description involves U_R.
5401 if Etype
(E1
) = Universal_Fixed
then
5403 Conv
: constant Node_Id
:= Make_Type_Conversion
(Loc
,
5404 Subtype_Mark
=> New_Occurrence_Of
(Universal_Real
, Loc
),
5405 Expression
=> Relocate_Node
(E1
));
5413 Resolve
(E1
, Any_Real
);
5419 when Attribute_Rounding
=>
5420 Check_Floating_Point_Type_1
;
5421 Set_Etype
(N
, P_Base_Type
);
5422 Resolve
(E1
, P_Base_Type
);
5428 when Attribute_Safe_Emax
=>
5429 Check_Floating_Point_Type_0
;
5430 Set_Etype
(N
, Universal_Integer
);
5436 when Attribute_Safe_First
=>
5437 Check_Floating_Point_Type_0
;
5438 Set_Etype
(N
, Universal_Real
);
5444 when Attribute_Safe_Large
=>
5447 Set_Etype
(N
, Universal_Real
);
5453 when Attribute_Safe_Last
=>
5454 Check_Floating_Point_Type_0
;
5455 Set_Etype
(N
, Universal_Real
);
5461 when Attribute_Safe_Small
=>
5464 Set_Etype
(N
, Universal_Real
);
5466 --------------------------
5467 -- Scalar_Storage_Order --
5468 --------------------------
5470 when Attribute_Scalar_Storage_Order
=> Scalar_Storage_Order
:
5472 Ent
: Entity_Id
:= Empty
;
5478 if not (Is_Record_Type
(P_Type
) or else Is_Array_Type
(P_Type
)) then
5480 -- In GNAT mode, the attribute applies to generic types as well
5481 -- as composite types, and for non-composite types always returns
5482 -- the default bit order for the target.
5484 if not (GNAT_Mode
and then Is_Generic_Type
(P_Type
))
5485 and then not In_Instance
5488 ("prefix of % attribute must be record or array type");
5490 elsif not Is_Generic_Type
(P_Type
) then
5491 if Bytes_Big_Endian
then
5492 Ent
:= RTE
(RE_High_Order_First
);
5494 Ent
:= RTE
(RE_Low_Order_First
);
5498 elsif Bytes_Big_Endian
xor Reverse_Storage_Order
(P_Type
) then
5499 Ent
:= RTE
(RE_High_Order_First
);
5502 Ent
:= RTE
(RE_Low_Order_First
);
5505 if Present
(Ent
) then
5506 Rewrite
(N
, New_Occurrence_Of
(Ent
, Loc
));
5509 Set_Etype
(N
, RTE
(RE_Bit_Order
));
5512 -- Reset incorrect indication of staticness
5514 Set_Is_Static_Expression
(N
, False);
5515 end Scalar_Storage_Order
;
5521 when Attribute_Scale
=>
5523 Check_Decimal_Fixed_Point_Type
;
5524 Set_Etype
(N
, Universal_Integer
);
5530 when Attribute_Scaling
=>
5531 Check_Floating_Point_Type_2
;
5532 Set_Etype
(N
, P_Base_Type
);
5533 Resolve
(E1
, P_Base_Type
);
5539 when Attribute_Signed_Zeros
=>
5540 Check_Floating_Point_Type_0
;
5541 Set_Etype
(N
, Standard_Boolean
);
5547 when Attribute_Size | Attribute_VADS_Size
=> Size
:
5551 -- If prefix is parameterless function call, rewrite and resolve
5554 if Is_Entity_Name
(P
)
5555 and then Ekind
(Entity
(P
)) = E_Function
5559 -- Similar processing for a protected function call
5561 elsif Nkind
(P
) = N_Selected_Component
5562 and then Ekind
(Entity
(Selector_Name
(P
))) = E_Function
5567 if Is_Object_Reference
(P
) then
5568 Check_Object_Reference
(P
);
5570 elsif Is_Entity_Name
(P
)
5571 and then (Is_Type
(Entity
(P
))
5572 or else Ekind
(Entity
(P
)) = E_Enumeration_Literal
)
5576 elsif Nkind
(P
) = N_Type_Conversion
5577 and then not Comes_From_Source
(P
)
5581 -- Some other compilers allow dubious use of X'???'Size
5583 elsif Relaxed_RM_Semantics
5584 and then Nkind
(P
) = N_Attribute_Reference
5589 Error_Attr_P
("invalid prefix for % attribute");
5592 Check_Not_Incomplete_Type
;
5594 Set_Etype
(N
, Universal_Integer
);
5601 when Attribute_Small
=>
5604 Set_Etype
(N
, Universal_Real
);
5610 when Attribute_Storage_Pool |
5611 Attribute_Simple_Storage_Pool
=> Storage_Pool
:
5615 if Is_Access_Type
(P_Type
) then
5616 if Ekind
(P_Type
) = E_Access_Subprogram_Type
then
5618 ("cannot use % attribute for access-to-subprogram type");
5621 -- Set appropriate entity
5623 if Present
(Associated_Storage_Pool
(Root_Type
(P_Type
))) then
5624 Set_Entity
(N
, Associated_Storage_Pool
(Root_Type
(P_Type
)));
5626 Set_Entity
(N
, RTE
(RE_Global_Pool_Object
));
5629 if Attr_Id
= Attribute_Storage_Pool
then
5630 if Present
(Get_Rep_Pragma
(Etype
(Entity
(N
)),
5631 Name_Simple_Storage_Pool_Type
))
5633 Error_Msg_Name_1
:= Aname
;
5634 Error_Msg_Warn
:= SPARK_Mode
/= On
;
5635 Error_Msg_N
("cannot use % attribute for type with simple "
5636 & "storage pool<<", N
);
5637 Error_Msg_N
("\Program_Error [<<", N
);
5640 (N
, Make_Raise_Program_Error
5641 (Sloc
(N
), Reason
=> PE_Explicit_Raise
));
5644 Set_Etype
(N
, Class_Wide_Type
(RTE
(RE_Root_Storage_Pool
)));
5646 -- In the Simple_Storage_Pool case, verify that the pool entity is
5647 -- actually of a simple storage pool type, and set the attribute's
5648 -- type to the pool object's type.
5651 if not Present
(Get_Rep_Pragma
(Etype
(Entity
(N
)),
5652 Name_Simple_Storage_Pool_Type
))
5655 ("cannot use % attribute for type without simple " &
5659 Set_Etype
(N
, Etype
(Entity
(N
)));
5662 -- Validate_Remote_Access_To_Class_Wide_Type for attribute
5663 -- Storage_Pool since this attribute is not defined for such
5664 -- types (RM E.2.3(22)).
5666 Validate_Remote_Access_To_Class_Wide_Type
(N
);
5669 Error_Attr_P
("prefix of % attribute must be access type");
5677 when Attribute_Storage_Size
=> Storage_Size
:
5681 if Is_Task_Type
(P_Type
) then
5682 Set_Etype
(N
, Universal_Integer
);
5684 -- Use with tasks is an obsolescent feature
5686 Check_Restriction
(No_Obsolescent_Features
, P
);
5688 elsif Is_Access_Type
(P_Type
) then
5689 if Ekind
(P_Type
) = E_Access_Subprogram_Type
then
5691 ("cannot use % attribute for access-to-subprogram type");
5694 if Is_Entity_Name
(P
)
5695 and then Is_Type
(Entity
(P
))
5698 Set_Etype
(N
, Universal_Integer
);
5700 -- Validate_Remote_Access_To_Class_Wide_Type for attribute
5701 -- Storage_Size since this attribute is not defined for
5702 -- such types (RM E.2.3(22)).
5704 Validate_Remote_Access_To_Class_Wide_Type
(N
);
5706 -- The prefix is allowed to be an implicit dereference of an
5707 -- access value designating a task.
5711 Set_Etype
(N
, Universal_Integer
);
5715 Error_Attr_P
("prefix of % attribute must be access or task type");
5723 when Attribute_Storage_Unit
=>
5724 Standard_Attribute
(Ttypes
.System_Storage_Unit
);
5730 when Attribute_Stream_Size
=>
5734 if Is_Entity_Name
(P
)
5735 and then Is_Elementary_Type
(Entity
(P
))
5737 Set_Etype
(N
, Universal_Integer
);
5739 Error_Attr_P
("invalid prefix for % attribute");
5746 when Attribute_Stub_Type
=>
5750 if Is_Remote_Access_To_Class_Wide_Type
(Base_Type
(P_Type
)) then
5752 -- For a real RACW [sub]type, use corresponding stub type
5754 if not Is_Generic_Type
(P_Type
) then
5757 (Corresponding_Stub_Type
(Base_Type
(P_Type
)), Loc
));
5759 -- For a generic type (that has been marked as an RACW using the
5760 -- Remote_Access_Type aspect or pragma), use a generic RACW stub
5761 -- type. Note that if the actual is not a remote access type, the
5762 -- instantiation will fail.
5765 -- Note: we go to the underlying type here because the view
5766 -- returned by RTE (RE_RACW_Stub_Type) might be incomplete.
5770 (Underlying_Type
(RTE
(RE_RACW_Stub_Type
)), Loc
));
5775 ("prefix of% attribute must be remote access to classwide");
5782 when Attribute_Succ
=>
5786 if Is_Real_Type
(P_Type
) or else Is_Boolean_Type
(P_Type
) then
5787 Error_Msg_Name_1
:= Aname
;
5788 Error_Msg_Name_2
:= Chars
(P_Type
);
5789 Check_SPARK_05_Restriction
5790 ("attribute% is not allowed for type%", P
);
5793 Resolve
(E1
, P_Base_Type
);
5794 Set_Etype
(N
, P_Base_Type
);
5796 -- Since Pred works on the base type, we normally do no check for the
5797 -- floating-point case, since the base type is unconstrained. But we
5798 -- make an exception in Check_Float_Overflow mode.
5800 if Is_Floating_Point_Type
(P_Type
) then
5801 if not Range_Checks_Suppressed
(P_Base_Type
) then
5802 Set_Do_Range_Check
(E1
);
5805 -- If not modular type, test for overflow check required
5808 if not Is_Modular_Integer_Type
(P_Type
)
5809 and then not Range_Checks_Suppressed
(P_Base_Type
)
5811 Enable_Range_Check
(E1
);
5815 --------------------------------
5816 -- System_Allocator_Alignment --
5817 --------------------------------
5819 when Attribute_System_Allocator_Alignment
=>
5820 Standard_Attribute
(Ttypes
.System_Allocator_Alignment
);
5826 when Attribute_Tag
=> Tag
:
5831 if not Is_Tagged_Type
(P_Type
) then
5832 Error_Attr_P
("prefix of % attribute must be tagged");
5834 -- Next test does not apply to generated code why not, and what does
5835 -- the illegal reference mean???
5837 elsif Is_Object_Reference
(P
)
5838 and then not Is_Class_Wide_Type
(P_Type
)
5839 and then Comes_From_Source
(N
)
5842 ("% attribute can only be applied to objects " &
5843 "of class - wide type");
5846 -- The prefix cannot be an incomplete type. However, references to
5847 -- 'Tag can be generated when expanding interface conversions, and
5850 if Comes_From_Source
(N
) then
5851 Check_Not_Incomplete_Type
;
5854 -- Set appropriate type
5856 Set_Etype
(N
, RTE
(RE_Tag
));
5863 when Attribute_Target_Name
=> Target_Name
: declare
5864 TN
: constant String := Sdefault
.Target_Name
.all;
5868 Check_Standard_Prefix
;
5872 if TN
(TL
) = '/' or else TN
(TL
) = '\' then
5877 Make_String_Literal
(Loc
,
5878 Strval
=> TN
(TN
'First .. TL
)));
5879 Analyze_And_Resolve
(N
, Standard_String
);
5880 Set_Is_Static_Expression
(N
, True);
5887 when Attribute_Terminated
=>
5889 Set_Etype
(N
, Standard_Boolean
);
5896 when Attribute_To_Address
=> To_Address
: declare
5902 Check_System_Prefix
;
5904 Generate_Reference
(RTE
(RE_Address
), P
);
5905 Analyze_And_Resolve
(E1
, Any_Integer
);
5906 Set_Etype
(N
, RTE
(RE_Address
));
5908 if Is_Static_Expression
(E1
) then
5909 Set_Is_Static_Expression
(N
, True);
5912 -- OK static expression case, check range and set appropriate type
5914 if Is_OK_Static_Expression
(E1
) then
5915 Val
:= Expr_Value
(E1
);
5917 if Val
< -(2 ** UI_From_Int
(Standard
'Address_Size - 1))
5919 Val
> 2 ** UI_From_Int
(Standard
'Address_Size) - 1
5921 Error_Attr
("address value out of range for % attribute", E1
);
5924 -- In most cases the expression is a numeric literal or some other
5925 -- address expression, but if it is a declared constant it may be
5926 -- of a compatible type that must be left on the node.
5928 if Is_Entity_Name
(E1
) then
5931 -- Set type to universal integer if negative
5934 Set_Etype
(E1
, Universal_Integer
);
5936 -- Otherwise set type to Unsigned_64 to accomodate max values
5939 Set_Etype
(E1
, Standard_Unsigned_64
);
5943 Set_Is_Static_Expression
(N
, True);
5950 when Attribute_To_Any
=>
5952 Check_PolyORB_Attribute
;
5953 Set_Etype
(N
, RTE
(RE_Any
));
5959 when Attribute_Truncation
=>
5960 Check_Floating_Point_Type_1
;
5961 Resolve
(E1
, P_Base_Type
);
5962 Set_Etype
(N
, P_Base_Type
);
5968 when Attribute_Type_Class
=>
5971 Check_Not_Incomplete_Type
;
5972 Set_Etype
(N
, RTE
(RE_Type_Class
));
5978 when Attribute_TypeCode
=>
5980 Check_PolyORB_Attribute
;
5981 Set_Etype
(N
, RTE
(RE_TypeCode
));
5987 when Attribute_Type_Key
=>
5991 -- This processing belongs in Eval_Attribute ???
5994 function Type_Key
return String_Id
;
5995 -- A very preliminary implementation. For now, a signature
5996 -- consists of only the type name. This is clearly incomplete
5997 -- (e.g., adding a new field to a record type should change the
5998 -- type's Type_Key attribute).
6004 function Type_Key
return String_Id
is
6005 Full_Name
: constant String_Id
:=
6006 Fully_Qualified_Name_String
(Entity
(P
));
6009 -- Copy all characters in Full_Name but the trailing NUL
6012 for J
in 1 .. String_Length
(Full_Name
) - 1 loop
6013 Store_String_Char
(Get_String_Char
(Full_Name
, Int
(J
)));
6016 Store_String_Chars
("'Type_Key");
6021 Rewrite
(N
, Make_String_Literal
(Loc
, Type_Key
));
6024 Analyze_And_Resolve
(N
, Standard_String
);
6030 when Attribute_UET_Address
=>
6032 Check_Unit_Name
(P
);
6033 Set_Etype
(N
, RTE
(RE_Address
));
6035 -----------------------
6036 -- Unbiased_Rounding --
6037 -----------------------
6039 when Attribute_Unbiased_Rounding
=>
6040 Check_Floating_Point_Type_1
;
6041 Set_Etype
(N
, P_Base_Type
);
6042 Resolve
(E1
, P_Base_Type
);
6044 ----------------------
6045 -- Unchecked_Access --
6046 ----------------------
6048 when Attribute_Unchecked_Access
=>
6049 if Comes_From_Source
(N
) then
6050 Check_Restriction
(No_Unchecked_Access
, N
);
6053 Analyze_Access_Attribute
;
6054 Check_Not_Incomplete_Type
;
6056 -------------------------
6057 -- Unconstrained_Array --
6058 -------------------------
6060 when Attribute_Unconstrained_Array
=>
6063 Check_Not_Incomplete_Type
;
6064 Set_Etype
(N
, Standard_Boolean
);
6065 Set_Is_Static_Expression
(N
, True);
6067 ------------------------------
6068 -- Universal_Literal_String --
6069 ------------------------------
6071 -- This is a GNAT specific attribute whose prefix must be a named
6072 -- number where the expression is either a single numeric literal,
6073 -- or a numeric literal immediately preceded by a minus sign. The
6074 -- result is equivalent to a string literal containing the text of
6075 -- the literal as it appeared in the source program with a possible
6076 -- leading minus sign.
6078 when Attribute_Universal_Literal_String
=> Universal_Literal_String
:
6082 if not Is_Entity_Name
(P
)
6083 or else Ekind
(Entity
(P
)) not in Named_Kind
6085 Error_Attr_P
("prefix for % attribute must be named number");
6092 Src
: Source_Buffer_Ptr
;
6095 Expr
:= Original_Node
(Expression
(Parent
(Entity
(P
))));
6097 if Nkind
(Expr
) = N_Op_Minus
then
6099 Expr
:= Original_Node
(Right_Opnd
(Expr
));
6104 if not Nkind_In
(Expr
, N_Integer_Literal
, N_Real_Literal
) then
6106 ("named number for % attribute must be simple literal", N
);
6109 -- Build string literal corresponding to source literal text
6114 Store_String_Char
(Get_Char_Code
('-'));
6118 Src
:= Source_Text
(Get_Source_File_Index
(S
));
6120 while Src
(S
) /= ';' and then Src
(S
) /= ' ' loop
6121 Store_String_Char
(Get_Char_Code
(Src
(S
)));
6125 -- Now we rewrite the attribute with the string literal
6128 Make_String_Literal
(Loc
, End_String
));
6130 Set_Is_Static_Expression
(N
, True);
6133 end Universal_Literal_String
;
6135 -------------------------
6136 -- Unrestricted_Access --
6137 -------------------------
6139 -- This is a GNAT specific attribute which is like Access except that
6140 -- all scope checks and checks for aliased views are omitted. It is
6141 -- documented as being equivalent to the use of the Address attribute
6142 -- followed by an unchecked conversion to the target access type.
6144 when Attribute_Unrestricted_Access
=>
6146 -- If from source, deal with relevant restrictions
6148 if Comes_From_Source
(N
) then
6149 Check_Restriction
(No_Unchecked_Access
, N
);
6151 if Nkind
(P
) in N_Has_Entity
6152 and then Present
(Entity
(P
))
6153 and then Is_Object
(Entity
(P
))
6155 Check_Restriction
(No_Implicit_Aliasing
, N
);
6159 if Is_Entity_Name
(P
) then
6160 Set_Address_Taken
(Entity
(P
));
6163 -- It might seem reasonable to call Address_Checks here to apply the
6164 -- same set of semantic checks that we enforce for 'Address (after
6165 -- all we document Unrestricted_Access as being equivalent to the
6166 -- use of Address followed by an Unchecked_Conversion). However, if
6167 -- we do enable these checks, we get multiple failures in both the
6168 -- compiler run-time and in our regression test suite, so we leave
6169 -- out these checks for now. To be investigated further some time???
6173 -- Now complete analysis using common access processing
6175 Analyze_Access_Attribute
;
6181 when Attribute_Update
=> Update
: declare
6182 Common_Typ
: Entity_Id
;
6183 -- The common type of a multiple component update for a record
6185 Comps
: Elist_Id
:= No_Elist
;
6186 -- A list used in the resolution of a record update. It contains the
6187 -- entities of all record components processed so far.
6189 procedure Analyze_Array_Component_Update
(Assoc
: Node_Id
);
6190 -- Analyze and resolve array_component_association Assoc against the
6191 -- index of array type P_Type.
6193 procedure Analyze_Record_Component_Update
(Comp
: Node_Id
);
6194 -- Analyze and resolve record_component_association Comp against
6195 -- record type P_Type.
6197 ------------------------------------
6198 -- Analyze_Array_Component_Update --
6199 ------------------------------------
6201 procedure Analyze_Array_Component_Update
(Assoc
: Node_Id
) is
6205 Index_Typ
: Entity_Id
;
6209 -- The current association contains a sequence of indexes denoting
6210 -- an element of a multidimensional array:
6212 -- (Index_1, ..., Index_N)
6214 -- Examine each individual index and resolve it against the proper
6215 -- index type of the array.
6217 if Nkind
(First
(Choices
(Assoc
))) = N_Aggregate
then
6218 Expr
:= First
(Choices
(Assoc
));
6219 while Present
(Expr
) loop
6221 -- The use of others is illegal (SPARK RM 4.4.1(12))
6223 if Nkind
(Expr
) = N_Others_Choice
then
6225 ("others choice not allowed in attribute %", Expr
);
6227 -- Otherwise analyze and resolve all indexes
6230 Index
:= First
(Expressions
(Expr
));
6231 Index_Typ
:= First_Index
(P_Type
);
6232 while Present
(Index
) and then Present
(Index_Typ
) loop
6233 Analyze_And_Resolve
(Index
, Etype
(Index_Typ
));
6235 Next_Index
(Index_Typ
);
6238 -- Detect a case where the association either lacks an
6239 -- index or contains an extra index.
6241 if Present
(Index
) or else Present
(Index_Typ
) then
6243 ("dimension mismatch in index list", Assoc
);
6250 -- The current association denotes either a single component or a
6251 -- range of components of a one dimensional array:
6255 -- Resolve the index or its high and low bounds (if range) against
6256 -- the proper index type of the array.
6259 Index
:= First
(Choices
(Assoc
));
6260 Index_Typ
:= First_Index
(P_Type
);
6262 if Present
(Next_Index
(Index_Typ
)) then
6263 Error_Msg_N
("too few subscripts in array reference", Assoc
);
6266 while Present
(Index
) loop
6268 -- The use of others is illegal (SPARK RM 4.4.1(12))
6270 if Nkind
(Index
) = N_Others_Choice
then
6272 ("others choice not allowed in attribute %", Index
);
6274 -- The index denotes a range of elements
6276 elsif Nkind
(Index
) = N_Range
then
6277 Low
:= Low_Bound
(Index
);
6278 High
:= High_Bound
(Index
);
6280 Analyze_And_Resolve
(Low
, Etype
(Index_Typ
));
6281 Analyze_And_Resolve
(High
, Etype
(Index_Typ
));
6283 -- Add a range check to ensure that the bounds of the
6284 -- range are within the index type when this cannot be
6285 -- determined statically.
6287 if not Is_OK_Static_Expression
(Low
) then
6288 Set_Do_Range_Check
(Low
);
6291 if not Is_OK_Static_Expression
(High
) then
6292 Set_Do_Range_Check
(High
);
6295 -- Otherwise the index denotes a single element
6298 Analyze_And_Resolve
(Index
, Etype
(Index_Typ
));
6300 -- Add a range check to ensure that the index is within
6301 -- the index type when it is not possible to determine
6304 if not Is_OK_Static_Expression
(Index
) then
6305 Set_Do_Range_Check
(Index
);
6312 end Analyze_Array_Component_Update
;
6314 -------------------------------------
6315 -- Analyze_Record_Component_Update --
6316 -------------------------------------
6318 procedure Analyze_Record_Component_Update
(Comp
: Node_Id
) is
6319 Comp_Name
: constant Name_Id
:= Chars
(Comp
);
6320 Base_Typ
: Entity_Id
;
6321 Comp_Or_Discr
: Entity_Id
;
6324 -- Find the discriminant or component whose name corresponds to
6325 -- Comp. A simple character comparison is sufficient because all
6326 -- visible names within a record type are unique.
6328 Comp_Or_Discr
:= First_Entity
(P_Type
);
6329 while Present
(Comp_Or_Discr
) loop
6330 if Chars
(Comp_Or_Discr
) = Comp_Name
then
6332 -- Decorate the component reference by setting its entity
6333 -- and type for resolution purposes.
6335 Set_Entity
(Comp
, Comp_Or_Discr
);
6336 Set_Etype
(Comp
, Etype
(Comp_Or_Discr
));
6340 Comp_Or_Discr
:= Next_Entity
(Comp_Or_Discr
);
6343 -- Diagnose an illegal reference
6345 if Present
(Comp_Or_Discr
) then
6346 if Ekind
(Comp_Or_Discr
) = E_Discriminant
then
6348 ("attribute % may not modify record discriminants", Comp
);
6350 else pragma Assert
(Ekind
(Comp_Or_Discr
) = E_Component
);
6351 if Contains
(Comps
, Comp_Or_Discr
) then
6352 Error_Msg_N
("component & already updated", Comp
);
6354 -- Mark this component as processed
6357 Append_New_Elmt
(Comp_Or_Discr
, Comps
);
6361 -- The update aggregate mentions an entity that does not belong to
6365 Error_Msg_N
("& is not a component of aggregate subtype", Comp
);
6368 -- Verify the consistency of types when the current component is
6369 -- part of a miltiple component update.
6371 -- Comp_1, ..., Comp_N => <value>
6373 if Present
(Etype
(Comp
)) then
6374 Base_Typ
:= Base_Type
(Etype
(Comp
));
6376 -- Save the type of the first component reference as the
6377 -- remaning references (if any) must resolve to this type.
6379 if No
(Common_Typ
) then
6380 Common_Typ
:= Base_Typ
;
6382 elsif Base_Typ
/= Common_Typ
then
6384 ("components in choice list must have same type", Comp
);
6387 end Analyze_Record_Component_Update
;
6394 -- Start of processing for Update
6399 if not Is_Object_Reference
(P
) then
6400 Error_Attr_P
("prefix of attribute % must denote an object");
6402 elsif not Is_Array_Type
(P_Type
)
6403 and then not Is_Record_Type
(P_Type
)
6405 Error_Attr_P
("prefix of attribute % must be a record or array");
6407 elsif Is_Limited_View
(P_Type
) then
6408 Error_Attr
("prefix of attribute % cannot be limited", N
);
6410 elsif Nkind
(E1
) /= N_Aggregate
then
6411 Error_Attr
("attribute % requires component association list", N
);
6414 -- Inspect the update aggregate, looking at all the associations and
6415 -- choices. Perform the following checks:
6417 -- 1) Legality of "others" in all cases
6418 -- 2) Legality of <>
6419 -- 3) Component legality for arrays
6420 -- 4) Component legality for records
6422 -- The remaining checks are performed on the expanded attribute
6424 Assoc
:= First
(Component_Associations
(E1
));
6425 while Present
(Assoc
) loop
6427 -- The use of <> is illegal (SPARK RM 4.4.1(1))
6429 if Box_Present
(Assoc
) then
6431 ("default initialization not allowed in attribute %", Assoc
);
6433 -- Otherwise process the association
6436 Analyze
(Expression
(Assoc
));
6438 if Is_Array_Type
(P_Type
) then
6439 Analyze_Array_Component_Update
(Assoc
);
6441 elsif Is_Record_Type
(P_Type
) then
6443 -- Reset the common type used in a multiple component update
6444 -- as we are processing the contents of a new association.
6446 Common_Typ
:= Empty
;
6448 Comp
:= First
(Choices
(Assoc
));
6449 while Present
(Comp
) loop
6450 if Nkind
(Comp
) = N_Identifier
then
6451 Analyze_Record_Component_Update
(Comp
);
6453 -- The use of others is illegal (SPARK RM 4.4.1(5))
6455 elsif Nkind
(Comp
) = N_Others_Choice
then
6457 ("others choice not allowed in attribute %", Comp
);
6459 -- The name of a record component cannot appear in any
6464 ("name should be identifier or OTHERS", Comp
);
6475 -- The type of attribute 'Update is that of the prefix
6477 Set_Etype
(N
, P_Type
);
6479 Sem_Warn
.Warn_On_Suspicious_Update
(N
);
6486 when Attribute_Val
=> Val
: declare
6489 Check_Discrete_Type
;
6491 if Is_Boolean_Type
(P_Type
) then
6492 Error_Msg_Name_1
:= Aname
;
6493 Error_Msg_Name_2
:= Chars
(P_Type
);
6494 Check_SPARK_05_Restriction
6495 ("attribute% is not allowed for type%", P
);
6498 Resolve
(E1
, Any_Integer
);
6499 Set_Etype
(N
, P_Base_Type
);
6501 -- Note, we need a range check in general, but we wait for the
6502 -- Resolve call to do this, since we want to let Eval_Attribute
6503 -- have a chance to find an static illegality first.
6510 when Attribute_Valid
=>
6513 -- Ignore check for object if we have a 'Valid reference generated
6514 -- by the expanded code, since in some cases valid checks can occur
6515 -- on items that are names, but are not objects (e.g. attributes).
6517 if Comes_From_Source
(N
) then
6518 Check_Object_Reference
(P
);
6521 if not Is_Scalar_Type
(P_Type
) then
6522 Error_Attr_P
("object for % attribute must be of scalar type");
6525 -- If the attribute appears within the subtype's own predicate
6526 -- function, then issue a warning that this will cause infinite
6530 Pred_Func
: constant Entity_Id
:= Predicate_Function
(P_Type
);
6533 if Present
(Pred_Func
) and then Current_Scope
= Pred_Func
then
6535 ("attribute Valid requires a predicate check??", N
);
6536 Error_Msg_N
("\and will result in infinite recursion??", N
);
6540 Set_Etype
(N
, Standard_Boolean
);
6546 when Attribute_Valid_Scalars
=>
6548 Check_Object_Reference
(P
);
6549 Set_Etype
(N
, Standard_Boolean
);
6551 -- Following checks are only for source types
6553 if Comes_From_Source
(N
) then
6554 if not Scalar_Part_Present
(P_Type
) then
6556 ("??attribute % always True, no scalars to check");
6559 -- Not allowed for unchecked union type
6561 if Has_Unchecked_Union
(P_Type
) then
6563 ("attribute % not allowed for Unchecked_Union type");
6571 when Attribute_Value
=> Value
:
6573 Check_SPARK_05_Restriction_On_Attribute
;
6577 -- Case of enumeration type
6579 -- When an enumeration type appears in an attribute reference, all
6580 -- literals of the type are marked as referenced. This must only be
6581 -- done if the attribute reference appears in the current source.
6582 -- Otherwise the information on references may differ between a
6583 -- normal compilation and one that performs inlining.
6585 if Is_Enumeration_Type
(P_Type
)
6586 and then In_Extended_Main_Code_Unit
(N
)
6588 Check_Restriction
(No_Enumeration_Maps
, N
);
6590 -- Mark all enumeration literals as referenced, since the use of
6591 -- the Value attribute can implicitly reference any of the
6592 -- literals of the enumeration base type.
6595 Ent
: Entity_Id
:= First_Literal
(P_Base_Type
);
6597 while Present
(Ent
) loop
6598 Set_Referenced
(Ent
);
6604 -- Set Etype before resolving expression because expansion of
6605 -- expression may require enclosing type. Note that the type
6606 -- returned by 'Value is the base type of the prefix type.
6608 Set_Etype
(N
, P_Base_Type
);
6609 Validate_Non_Static_Attribute_Function_Call
;
6611 -- Check restriction No_Fixed_IO
6613 if Restriction_Check_Required
(No_Fixed_IO
)
6614 and then Is_Fixed_Point_Type
(P_Type
)
6616 Check_Restriction
(No_Fixed_IO
, P
);
6624 when Attribute_Value_Size
=>
6627 Check_Not_Incomplete_Type
;
6628 Set_Etype
(N
, Universal_Integer
);
6634 when Attribute_Version
=>
6637 Set_Etype
(N
, RTE
(RE_Version_String
));
6643 when Attribute_Wchar_T_Size
=>
6644 Standard_Attribute
(Interfaces_Wchar_T_Size
);
6650 when Attribute_Wide_Image
=> Wide_Image
:
6652 Check_SPARK_05_Restriction_On_Attribute
;
6654 Set_Etype
(N
, Standard_Wide_String
);
6656 Resolve
(E1
, P_Base_Type
);
6657 Validate_Non_Static_Attribute_Function_Call
;
6659 -- Check restriction No_Fixed_IO
6661 if Restriction_Check_Required
(No_Fixed_IO
)
6662 and then Is_Fixed_Point_Type
(P_Type
)
6664 Check_Restriction
(No_Fixed_IO
, P
);
6668 ---------------------
6669 -- Wide_Wide_Image --
6670 ---------------------
6672 when Attribute_Wide_Wide_Image
=> Wide_Wide_Image
:
6675 Set_Etype
(N
, Standard_Wide_Wide_String
);
6677 Resolve
(E1
, P_Base_Type
);
6678 Validate_Non_Static_Attribute_Function_Call
;
6680 -- Check restriction No_Fixed_IO
6682 if Restriction_Check_Required
(No_Fixed_IO
)
6683 and then Is_Fixed_Point_Type
(P_Type
)
6685 Check_Restriction
(No_Fixed_IO
, P
);
6687 end Wide_Wide_Image
;
6693 when Attribute_Wide_Value
=> Wide_Value
:
6695 Check_SPARK_05_Restriction_On_Attribute
;
6699 -- Set Etype before resolving expression because expansion
6700 -- of expression may require enclosing type.
6702 Set_Etype
(N
, P_Type
);
6703 Validate_Non_Static_Attribute_Function_Call
;
6705 -- Check restriction No_Fixed_IO
6707 if Restriction_Check_Required
(No_Fixed_IO
)
6708 and then Is_Fixed_Point_Type
(P_Type
)
6710 Check_Restriction
(No_Fixed_IO
, P
);
6714 ---------------------
6715 -- Wide_Wide_Value --
6716 ---------------------
6718 when Attribute_Wide_Wide_Value
=> Wide_Wide_Value
:
6723 -- Set Etype before resolving expression because expansion
6724 -- of expression may require enclosing type.
6726 Set_Etype
(N
, P_Type
);
6727 Validate_Non_Static_Attribute_Function_Call
;
6729 -- Check restriction No_Fixed_IO
6731 if Restriction_Check_Required
(No_Fixed_IO
)
6732 and then Is_Fixed_Point_Type
(P_Type
)
6734 Check_Restriction
(No_Fixed_IO
, P
);
6736 end Wide_Wide_Value
;
6738 ---------------------
6739 -- Wide_Wide_Width --
6740 ---------------------
6742 when Attribute_Wide_Wide_Width
=>
6745 Set_Etype
(N
, Universal_Integer
);
6751 when Attribute_Wide_Width
=>
6752 Check_SPARK_05_Restriction_On_Attribute
;
6755 Set_Etype
(N
, Universal_Integer
);
6761 when Attribute_Width
=>
6762 Check_SPARK_05_Restriction_On_Attribute
;
6765 Set_Etype
(N
, Universal_Integer
);
6771 when Attribute_Word_Size
=>
6772 Standard_Attribute
(System_Word_Size
);
6778 when Attribute_Write
=>
6780 Check_Stream_Attribute
(TSS_Stream_Write
);
6781 Set_Etype
(N
, Standard_Void_Type
);
6782 Resolve
(N
, Standard_Void_Type
);
6786 -- All errors raise Bad_Attribute, so that we get out before any further
6787 -- damage occurs when an error is detected (for example, if we check for
6788 -- one attribute expression, and the check succeeds, we want to be able
6789 -- to proceed securely assuming that an expression is in fact present.
6791 -- Note: we set the attribute analyzed in this case to prevent any
6792 -- attempt at reanalysis which could generate spurious error msgs.
6795 when Bad_Attribute
=>
6797 Set_Etype
(N
, Any_Type
);
6799 end Analyze_Attribute
;
6801 --------------------
6802 -- Eval_Attribute --
6803 --------------------
6805 procedure Eval_Attribute
(N
: Node_Id
) is
6806 Loc
: constant Source_Ptr
:= Sloc
(N
);
6807 Aname
: constant Name_Id
:= Attribute_Name
(N
);
6808 Id
: constant Attribute_Id
:= Get_Attribute_Id
(Aname
);
6809 P
: constant Node_Id
:= Prefix
(N
);
6811 C_Type
: constant Entity_Id
:= Etype
(N
);
6812 -- The type imposed by the context
6815 -- First expression, or Empty if none
6818 -- Second expression, or Empty if none
6820 P_Entity
: Entity_Id
;
6821 -- Entity denoted by prefix
6824 -- The type of the prefix
6826 P_Base_Type
: Entity_Id
;
6827 -- The base type of the prefix type
6829 P_Root_Type
: Entity_Id
;
6830 -- The root type of the prefix type
6833 -- True if the result is Static. This is set by the general processing
6834 -- to true if the prefix is static, and all expressions are static. It
6835 -- can be reset as processing continues for particular attributes. This
6836 -- flag can still be True if the reference raises a constraint error.
6837 -- Is_Static_Expression (N) is set to follow this value as it is set
6838 -- and we could always reference this, but it is convenient to have a
6839 -- simple short name to use, since it is frequently referenced.
6841 Lo_Bound
, Hi_Bound
: Node_Id
;
6842 -- Expressions for low and high bounds of type or array index referenced
6843 -- by First, Last, or Length attribute for array, set by Set_Bounds.
6846 -- Constraint error node used if we have an attribute reference has
6847 -- an argument that raises a constraint error. In this case we replace
6848 -- the attribute with a raise constraint_error node. This is important
6849 -- processing, since otherwise gigi might see an attribute which it is
6850 -- unprepared to deal with.
6852 procedure Check_Concurrent_Discriminant
(Bound
: Node_Id
);
6853 -- If Bound is a reference to a discriminant of a task or protected type
6854 -- occurring within the object's body, rewrite attribute reference into
6855 -- a reference to the corresponding discriminal. Use for the expansion
6856 -- of checks against bounds of entry family index subtypes.
6858 procedure Check_Expressions
;
6859 -- In case where the attribute is not foldable, the expressions, if
6860 -- any, of the attribute, are in a non-static context. This procedure
6861 -- performs the required additional checks.
6863 function Compile_Time_Known_Bounds
(Typ
: Entity_Id
) return Boolean;
6864 -- Determines if the given type has compile time known bounds. Note
6865 -- that we enter the case statement even in cases where the prefix
6866 -- type does NOT have known bounds, so it is important to guard any
6867 -- attempt to evaluate both bounds with a call to this function.
6869 procedure Compile_Time_Known_Attribute
(N
: Node_Id
; Val
: Uint
);
6870 -- This procedure is called when the attribute N has a non-static
6871 -- but compile time known value given by Val. It includes the
6872 -- necessary checks for out of range values.
6874 function Fore_Value
return Nat
;
6875 -- Computes the Fore value for the current attribute prefix, which is
6876 -- known to be a static fixed-point type. Used by Fore and Width.
6878 function Mantissa
return Uint
;
6879 -- Returns the Mantissa value for the prefix type
6881 procedure Set_Bounds
;
6882 -- Used for First, Last and Length attributes applied to an array or
6883 -- array subtype. Sets the variables Lo_Bound and Hi_Bound to the low
6884 -- and high bound expressions for the index referenced by the attribute
6885 -- designator (i.e. the first index if no expression is present, and the
6886 -- N'th index if the value N is present as an expression). Also used for
6887 -- First and Last of scalar types and for First_Valid and Last_Valid.
6888 -- Static is reset to False if the type or index type is not statically
6891 function Statically_Denotes_Entity
(N
: Node_Id
) return Boolean;
6892 -- Verify that the prefix of a potentially static array attribute
6893 -- satisfies the conditions of 4.9 (14).
6895 -----------------------------------
6896 -- Check_Concurrent_Discriminant --
6897 -----------------------------------
6899 procedure Check_Concurrent_Discriminant
(Bound
: Node_Id
) is
6901 -- The concurrent (task or protected) type
6904 if Nkind
(Bound
) = N_Identifier
6905 and then Ekind
(Entity
(Bound
)) = E_Discriminant
6906 and then Is_Concurrent_Record_Type
(Scope
(Entity
(Bound
)))
6908 Tsk
:= Corresponding_Concurrent_Type
(Scope
(Entity
(Bound
)));
6910 if In_Open_Scopes
(Tsk
) and then Has_Completion
(Tsk
) then
6912 -- Find discriminant of original concurrent type, and use
6913 -- its current discriminal, which is the renaming within
6914 -- the task/protected body.
6918 (Find_Body_Discriminal
(Entity
(Bound
)), Loc
));
6921 end Check_Concurrent_Discriminant
;
6923 -----------------------
6924 -- Check_Expressions --
6925 -----------------------
6927 procedure Check_Expressions
is
6931 while Present
(E
) loop
6932 Check_Non_Static_Context
(E
);
6935 end Check_Expressions
;
6937 ----------------------------------
6938 -- Compile_Time_Known_Attribute --
6939 ----------------------------------
6941 procedure Compile_Time_Known_Attribute
(N
: Node_Id
; Val
: Uint
) is
6942 T
: constant Entity_Id
:= Etype
(N
);
6945 Fold_Uint
(N
, Val
, False);
6947 -- Check that result is in bounds of the type if it is static
6949 if Is_In_Range
(N
, T
, Assume_Valid
=> False) then
6952 elsif Is_Out_Of_Range
(N
, T
) then
6953 Apply_Compile_Time_Constraint_Error
6954 (N
, "value not in range of}??", CE_Range_Check_Failed
);
6956 elsif not Range_Checks_Suppressed
(T
) then
6957 Enable_Range_Check
(N
);
6960 Set_Do_Range_Check
(N
, False);
6962 end Compile_Time_Known_Attribute
;
6964 -------------------------------
6965 -- Compile_Time_Known_Bounds --
6966 -------------------------------
6968 function Compile_Time_Known_Bounds
(Typ
: Entity_Id
) return Boolean is
6971 Compile_Time_Known_Value
(Type_Low_Bound
(Typ
))
6973 Compile_Time_Known_Value
(Type_High_Bound
(Typ
));
6974 end Compile_Time_Known_Bounds
;
6980 -- Note that the Fore calculation is based on the actual values
6981 -- of the bounds, and does not take into account possible rounding.
6983 function Fore_Value
return Nat
is
6984 Lo
: constant Uint
:= Expr_Value
(Type_Low_Bound
(P_Type
));
6985 Hi
: constant Uint
:= Expr_Value
(Type_High_Bound
(P_Type
));
6986 Small
: constant Ureal
:= Small_Value
(P_Type
);
6987 Lo_Real
: constant Ureal
:= Lo
* Small
;
6988 Hi_Real
: constant Ureal
:= Hi
* Small
;
6993 -- Bounds are given in terms of small units, so first compute
6994 -- proper values as reals.
6996 T
:= UR_Max
(abs Lo_Real
, abs Hi_Real
);
6999 -- Loop to compute proper value if more than one digit required
7001 while T
>= Ureal_10
loop
7013 -- Table of mantissa values accessed by function Computed using
7016 -- T'Mantissa = integer next above (D * log(10)/log(2)) + 1)
7018 -- where D is T'Digits (RM83 3.5.7)
7020 Mantissa_Value
: constant array (Nat
range 1 .. 40) of Nat
:= (
7062 function Mantissa
return Uint
is
7065 UI_From_Int
(Mantissa_Value
(UI_To_Int
(Digits_Value
(P_Type
))));
7072 procedure Set_Bounds
is
7078 -- For a string literal subtype, we have to construct the bounds.
7079 -- Valid Ada code never applies attributes to string literals, but
7080 -- it is convenient to allow the expander to generate attribute
7081 -- references of this type (e.g. First and Last applied to a string
7084 -- Note that the whole point of the E_String_Literal_Subtype is to
7085 -- avoid this construction of bounds, but the cases in which we
7086 -- have to materialize them are rare enough that we don't worry.
7088 -- The low bound is simply the low bound of the base type. The
7089 -- high bound is computed from the length of the string and this
7092 if Ekind
(P_Type
) = E_String_Literal_Subtype
then
7093 Ityp
:= Etype
(First_Index
(Base_Type
(P_Type
)));
7094 Lo_Bound
:= Type_Low_Bound
(Ityp
);
7097 Make_Integer_Literal
(Sloc
(P
),
7099 Expr_Value
(Lo_Bound
) + String_Literal_Length
(P_Type
) - 1);
7101 Set_Parent
(Hi_Bound
, P
);
7102 Analyze_And_Resolve
(Hi_Bound
, Etype
(Lo_Bound
));
7105 -- For non-array case, just get bounds of scalar type
7107 elsif Is_Scalar_Type
(P_Type
) then
7110 -- For a fixed-point type, we must freeze to get the attributes
7111 -- of the fixed-point type set now so we can reference them.
7113 if Is_Fixed_Point_Type
(P_Type
)
7114 and then not Is_Frozen
(Base_Type
(P_Type
))
7115 and then Compile_Time_Known_Value
(Type_Low_Bound
(P_Type
))
7116 and then Compile_Time_Known_Value
(Type_High_Bound
(P_Type
))
7118 Freeze_Fixed_Point_Type
(Base_Type
(P_Type
));
7121 -- For array case, get type of proper index
7127 Ndim
:= UI_To_Int
(Expr_Value
(E1
));
7130 Indx
:= First_Index
(P_Type
);
7131 for J
in 1 .. Ndim
- 1 loop
7135 -- If no index type, get out (some other error occurred, and
7136 -- we don't have enough information to complete the job).
7144 Ityp
:= Etype
(Indx
);
7147 -- A discrete range in an index constraint is allowed to be a
7148 -- subtype indication. This is syntactically a pain, but should
7149 -- not propagate to the entity for the corresponding index subtype.
7150 -- After checking that the subtype indication is legal, the range
7151 -- of the subtype indication should be transfered to the entity.
7152 -- The attributes for the bounds should remain the simple retrievals
7153 -- that they are now.
7155 Lo_Bound
:= Type_Low_Bound
(Ityp
);
7156 Hi_Bound
:= Type_High_Bound
(Ityp
);
7158 -- If subtype is non-static, result is definitely non-static
7160 if not Is_Static_Subtype
(Ityp
) then
7162 Set_Is_Static_Expression
(N
, False);
7164 -- Subtype is static, does it raise CE?
7166 elsif not Is_OK_Static_Subtype
(Ityp
) then
7167 Set_Raises_Constraint_Error
(N
);
7171 -------------------------------
7172 -- Statically_Denotes_Entity --
7173 -------------------------------
7175 function Statically_Denotes_Entity
(N
: Node_Id
) return Boolean is
7179 if not Is_Entity_Name
(N
) then
7186 Nkind
(Parent
(E
)) /= N_Object_Renaming_Declaration
7187 or else Statically_Denotes_Entity
(Renamed_Object
(E
));
7188 end Statically_Denotes_Entity
;
7190 -- Start of processing for Eval_Attribute
7193 -- Initialize result as non-static, will be reset if appropriate
7195 Set_Is_Static_Expression
(N
, False);
7198 -- Acquire first two expressions (at the moment, no attributes take more
7199 -- than two expressions in any case).
7201 if Present
(Expressions
(N
)) then
7202 E1
:= First
(Expressions
(N
));
7209 -- Special processing for Enabled attribute. This attribute has a very
7210 -- special prefix, and the easiest way to avoid lots of special checks
7211 -- to protect this special prefix from causing trouble is to deal with
7212 -- this attribute immediately and be done with it.
7214 if Id
= Attribute_Enabled
then
7216 -- We skip evaluation if the expander is not active. This is not just
7217 -- an optimization. It is of key importance that we not rewrite the
7218 -- attribute in a generic template, since we want to pick up the
7219 -- setting of the check in the instance, and testing expander active
7220 -- is as easy way of doing this as any.
7222 if Expander_Active
then
7224 C
: constant Check_Id
:= Get_Check_Id
(Chars
(P
));
7229 if C
in Predefined_Check_Id
then
7230 R
:= Scope_Suppress
.Suppress
(C
);
7232 R
:= Is_Check_Suppressed
(Empty
, C
);
7236 R
:= Is_Check_Suppressed
(Entity
(E1
), C
);
7239 Rewrite
(N
, New_Occurrence_Of
(Boolean_Literals
(not R
), Loc
));
7246 -- Attribute 'Img applied to a static enumeration value is static, and
7247 -- we will do the folding right here (things get confused if we let this
7248 -- case go through the normal circuitry).
7250 if Attribute_Name
(N
) = Name_Img
7251 and then Is_Entity_Name
(P
)
7252 and then Is_Enumeration_Type
(Etype
(Entity
(P
)))
7253 and then Is_OK_Static_Expression
(P
)
7256 Lit
: constant Entity_Id
:= Expr_Value_E
(P
);
7261 Get_Unqualified_Decoded_Name_String
(Chars
(Lit
));
7262 Set_Casing
(All_Upper_Case
);
7263 Store_String_Chars
(Name_Buffer
(1 .. Name_Len
));
7266 Rewrite
(N
, Make_String_Literal
(Loc
, Strval
=> Str
));
7267 Analyze_And_Resolve
(N
, Standard_String
);
7268 Set_Is_Static_Expression
(N
, True);
7274 -- Special processing for cases where the prefix is an object. For
7275 -- this purpose, a string literal counts as an object (attributes
7276 -- of string literals can only appear in generated code).
7278 if Is_Object_Reference
(P
) or else Nkind
(P
) = N_String_Literal
then
7280 -- For Component_Size, the prefix is an array object, and we apply
7281 -- the attribute to the type of the object. This is allowed for
7282 -- both unconstrained and constrained arrays, since the bounds
7283 -- have no influence on the value of this attribute.
7285 if Id
= Attribute_Component_Size
then
7286 P_Entity
:= Etype
(P
);
7288 -- For First and Last, the prefix is an array object, and we apply
7289 -- the attribute to the type of the array, but we need a constrained
7290 -- type for this, so we use the actual subtype if available.
7292 elsif Id
= Attribute_First
or else
7293 Id
= Attribute_Last
or else
7294 Id
= Attribute_Length
7297 AS
: constant Entity_Id
:= Get_Actual_Subtype_If_Available
(P
);
7300 if Present
(AS
) and then Is_Constrained
(AS
) then
7303 -- If we have an unconstrained type we cannot fold
7311 -- For Size, give size of object if available, otherwise we
7312 -- cannot fold Size.
7314 elsif Id
= Attribute_Size
then
7315 if Is_Entity_Name
(P
)
7316 and then Known_Esize
(Entity
(P
))
7318 Compile_Time_Known_Attribute
(N
, Esize
(Entity
(P
)));
7326 -- For Alignment, give size of object if available, otherwise we
7327 -- cannot fold Alignment.
7329 elsif Id
= Attribute_Alignment
then
7330 if Is_Entity_Name
(P
)
7331 and then Known_Alignment
(Entity
(P
))
7333 Fold_Uint
(N
, Alignment
(Entity
(P
)), Static
);
7341 -- For Lock_Free, we apply the attribute to the type of the object.
7342 -- This is allowed since we have already verified that the type is a
7345 elsif Id
= Attribute_Lock_Free
then
7346 P_Entity
:= Etype
(P
);
7348 -- No other attributes for objects are folded
7355 -- Cases where P is not an object. Cannot do anything if P is not the
7356 -- name of an entity.
7358 elsif not Is_Entity_Name
(P
) then
7362 -- Otherwise get prefix entity
7365 P_Entity
:= Entity
(P
);
7368 -- If we are asked to evaluate an attribute where the prefix is a
7369 -- non-frozen generic actual type whose RM_Size is still set to zero,
7370 -- then abandon the effort.
7372 if Is_Type
(P_Entity
)
7373 and then (not Is_Frozen
(P_Entity
)
7374 and then Is_Generic_Actual_Type
(P_Entity
)
7375 and then RM_Size
(P_Entity
) = 0)
7377 -- However, the attribute Unconstrained_Array must be evaluated,
7378 -- since it is documented to be a static attribute (and can for
7379 -- example appear in a Compile_Time_Warning pragma). The frozen
7380 -- status of the type does not affect its evaluation.
7382 and then Id
/= Attribute_Unconstrained_Array
7387 -- At this stage P_Entity is the entity to which the attribute
7388 -- is to be applied. This is usually simply the entity of the
7389 -- prefix, except in some cases of attributes for objects, where
7390 -- as described above, we apply the attribute to the object type.
7392 -- Here is where we make sure that static attributes are properly
7393 -- marked as such. These are attributes whose prefix is a static
7394 -- scalar subtype, whose result is scalar, and whose arguments, if
7395 -- present, are static scalar expressions. Note that such references
7396 -- are static expressions even if they raise Constraint_Error.
7398 -- For example, Boolean'Pos (1/0 = 0) is a static expression, even
7399 -- though evaluating it raises constraint error. This means that a
7400 -- declaration like:
7402 -- X : constant := (if True then 1 else Boolean'Pos (1/0 = 0));
7404 -- is legal, since here this expression appears in a statically
7405 -- unevaluated position, so it does not actually raise an exception.
7407 if Is_Scalar_Type
(P_Entity
)
7408 and then (not Is_Generic_Type
(P_Entity
))
7409 and then Is_Static_Subtype
(P_Entity
)
7410 and then Is_Scalar_Type
(Etype
(N
))
7413 or else (Is_Static_Expression
(E1
)
7414 and then Is_Scalar_Type
(Etype
(E1
))))
7417 or else (Is_Static_Expression
(E2
)
7418 and then Is_Scalar_Type
(Etype
(E1
))))
7421 Set_Is_Static_Expression
(N
, True);
7424 -- First foldable possibility is a scalar or array type (RM 4.9(7))
7425 -- that is not generic (generic types are eliminated by RM 4.9(25)).
7426 -- Note we allow non-static non-generic types at this stage as further
7429 if Is_Type
(P_Entity
)
7430 and then (Is_Scalar_Type
(P_Entity
) or Is_Array_Type
(P_Entity
))
7431 and then (not Is_Generic_Type
(P_Entity
))
7435 -- Second foldable possibility is an array object (RM 4.9(8))
7437 elsif Ekind_In
(P_Entity
, E_Variable
, E_Constant
)
7438 and then Is_Array_Type
(Etype
(P_Entity
))
7439 and then (not Is_Generic_Type
(Etype
(P_Entity
)))
7441 P_Type
:= Etype
(P_Entity
);
7443 -- If the entity is an array constant with an unconstrained nominal
7444 -- subtype then get the type from the initial value. If the value has
7445 -- been expanded into assignments, there is no expression and the
7446 -- attribute reference remains dynamic.
7448 -- We could do better here and retrieve the type ???
7450 if Ekind
(P_Entity
) = E_Constant
7451 and then not Is_Constrained
(P_Type
)
7453 if No
(Constant_Value
(P_Entity
)) then
7456 P_Type
:= Etype
(Constant_Value
(P_Entity
));
7460 -- Definite must be folded if the prefix is not a generic type, that
7461 -- is to say if we are within an instantiation. Same processing applies
7462 -- to the GNAT attributes Atomic_Always_Lock_Free, Has_Discriminants,
7463 -- Lock_Free, Type_Class, Has_Tagged_Value, and Unconstrained_Array.
7465 elsif (Id
= Attribute_Atomic_Always_Lock_Free
or else
7466 Id
= Attribute_Definite
or else
7467 Id
= Attribute_Has_Access_Values
or else
7468 Id
= Attribute_Has_Discriminants
or else
7469 Id
= Attribute_Has_Tagged_Values
or else
7470 Id
= Attribute_Lock_Free
or else
7471 Id
= Attribute_Type_Class
or else
7472 Id
= Attribute_Unconstrained_Array
or else
7473 Id
= Attribute_Max_Alignment_For_Allocation
)
7474 and then not Is_Generic_Type
(P_Entity
)
7478 -- We can fold 'Size applied to a type if the size is known (as happens
7479 -- for a size from an attribute definition clause). At this stage, this
7480 -- can happen only for types (e.g. record types) for which the size is
7481 -- always non-static. We exclude generic types from consideration (since
7482 -- they have bogus sizes set within templates).
7484 elsif Id
= Attribute_Size
7485 and then Is_Type
(P_Entity
)
7486 and then (not Is_Generic_Type
(P_Entity
))
7487 and then Known_Static_RM_Size
(P_Entity
)
7489 Compile_Time_Known_Attribute
(N
, RM_Size
(P_Entity
));
7492 -- We can fold 'Alignment applied to a type if the alignment is known
7493 -- (as happens for an alignment from an attribute definition clause).
7494 -- At this stage, this can happen only for types (e.g. record types) for
7495 -- which the size is always non-static. We exclude generic types from
7496 -- consideration (since they have bogus sizes set within templates).
7498 elsif Id
= Attribute_Alignment
7499 and then Is_Type
(P_Entity
)
7500 and then (not Is_Generic_Type
(P_Entity
))
7501 and then Known_Alignment
(P_Entity
)
7503 Compile_Time_Known_Attribute
(N
, Alignment
(P_Entity
));
7506 -- If this is an access attribute that is known to fail accessibility
7507 -- check, rewrite accordingly.
7509 elsif Attribute_Name
(N
) = Name_Access
7510 and then Raises_Constraint_Error
(N
)
7513 Make_Raise_Program_Error
(Loc
,
7514 Reason
=> PE_Accessibility_Check_Failed
));
7515 Set_Etype
(N
, C_Type
);
7518 -- No other cases are foldable (they certainly aren't static, and at
7519 -- the moment we don't try to fold any cases other than the ones above).
7526 -- If either attribute or the prefix is Any_Type, then propagate
7527 -- Any_Type to the result and don't do anything else at all.
7529 if P_Type
= Any_Type
7530 or else (Present
(E1
) and then Etype
(E1
) = Any_Type
)
7531 or else (Present
(E2
) and then Etype
(E2
) = Any_Type
)
7533 Set_Etype
(N
, Any_Type
);
7537 -- Scalar subtype case. We have not yet enforced the static requirement
7538 -- of (RM 4.9(7)) and we don't intend to just yet, since there are cases
7539 -- of non-static attribute references (e.g. S'Digits for a non-static
7540 -- floating-point type, which we can compute at compile time).
7542 -- Note: this folding of non-static attributes is not simply a case of
7543 -- optimization. For many of the attributes affected, Gigi cannot handle
7544 -- the attribute and depends on the front end having folded them away.
7546 -- Note: although we don't require staticness at this stage, we do set
7547 -- the Static variable to record the staticness, for easy reference by
7548 -- those attributes where it matters (e.g. Succ and Pred), and also to
7549 -- be used to ensure that non-static folded things are not marked as
7550 -- being static (a check that is done right at the end).
7552 P_Root_Type
:= Root_Type
(P_Type
);
7553 P_Base_Type
:= Base_Type
(P_Type
);
7555 -- If the root type or base type is generic, then we cannot fold. This
7556 -- test is needed because subtypes of generic types are not always
7557 -- marked as being generic themselves (which seems odd???)
7559 if Is_Generic_Type
(P_Root_Type
)
7560 or else Is_Generic_Type
(P_Base_Type
)
7565 if Is_Scalar_Type
(P_Type
) then
7566 if not Is_Static_Subtype
(P_Type
) then
7568 Set_Is_Static_Expression
(N
, False);
7569 elsif not Is_OK_Static_Subtype
(P_Type
) then
7570 Set_Raises_Constraint_Error
(N
);
7573 -- Array case. We enforce the constrained requirement of (RM 4.9(7-8))
7574 -- since we can't do anything with unconstrained arrays. In addition,
7575 -- only the First, Last and Length attributes are possibly static.
7577 -- Atomic_Always_Lock_Free, Definite, Has_Access_Values,
7578 -- Has_Discriminants, Has_Tagged_Values, Lock_Free, Type_Class, and
7579 -- Unconstrained_Array are again exceptions, because they apply as well
7580 -- to unconstrained types.
7582 -- In addition Component_Size is an exception since it is possibly
7583 -- foldable, even though it is never static, and it does apply to
7584 -- unconstrained arrays. Furthermore, it is essential to fold this
7585 -- in the packed case, since otherwise the value will be incorrect.
7587 elsif Id
= Attribute_Atomic_Always_Lock_Free
or else
7588 Id
= Attribute_Definite
or else
7589 Id
= Attribute_Has_Access_Values
or else
7590 Id
= Attribute_Has_Discriminants
or else
7591 Id
= Attribute_Has_Tagged_Values
or else
7592 Id
= Attribute_Lock_Free
or else
7593 Id
= Attribute_Type_Class
or else
7594 Id
= Attribute_Unconstrained_Array
or else
7595 Id
= Attribute_Component_Size
7598 Set_Is_Static_Expression
(N
, False);
7600 elsif Id
/= Attribute_Max_Alignment_For_Allocation
then
7601 if not Is_Constrained
(P_Type
)
7602 or else (Id
/= Attribute_First
and then
7603 Id
/= Attribute_Last
and then
7604 Id
/= Attribute_Length
)
7610 -- The rules in (RM 4.9(7,8)) require a static array, but as in the
7611 -- scalar case, we hold off on enforcing staticness, since there are
7612 -- cases which we can fold at compile time even though they are not
7613 -- static (e.g. 'Length applied to a static index, even though other
7614 -- non-static indexes make the array type non-static). This is only
7615 -- an optimization, but it falls out essentially free, so why not.
7616 -- Again we compute the variable Static for easy reference later
7617 -- (note that no array attributes are static in Ada 83).
7619 -- We also need to set Static properly for subsequent legality checks
7620 -- which might otherwise accept non-static constants in contexts
7621 -- where they are not legal.
7624 Ada_Version
>= Ada_95
and then Statically_Denotes_Entity
(P
);
7625 Set_Is_Static_Expression
(N
, Static
);
7631 Nod
:= First_Index
(P_Type
);
7633 -- The expression is static if the array type is constrained
7634 -- by given bounds, and not by an initial expression. Constant
7635 -- strings are static in any case.
7637 if Root_Type
(P_Type
) /= Standard_String
then
7639 Static
and then not Is_Constr_Subt_For_U_Nominal
(P_Type
);
7640 Set_Is_Static_Expression
(N
, Static
);
7643 while Present
(Nod
) loop
7644 if not Is_Static_Subtype
(Etype
(Nod
)) then
7646 Set_Is_Static_Expression
(N
, False);
7648 elsif not Is_OK_Static_Subtype
(Etype
(Nod
)) then
7649 Set_Raises_Constraint_Error
(N
);
7651 Set_Is_Static_Expression
(N
, False);
7654 -- If however the index type is generic, or derived from
7655 -- one, attributes cannot be folded.
7657 if Is_Generic_Type
(Root_Type
(Etype
(Nod
)))
7658 and then Id
/= Attribute_Component_Size
7668 -- Check any expressions that are present. Note that these expressions,
7669 -- depending on the particular attribute type, are either part of the
7670 -- attribute designator, or they are arguments in a case where the
7671 -- attribute reference returns a function. In the latter case, the
7672 -- rule in (RM 4.9(22)) applies and in particular requires the type
7673 -- of the expressions to be scalar in order for the attribute to be
7674 -- considered to be static.
7682 while Present
(E
) loop
7684 -- If expression is not static, then the attribute reference
7685 -- result certainly cannot be static.
7687 if not Is_Static_Expression
(E
) then
7689 Set_Is_Static_Expression
(N
, False);
7692 if Raises_Constraint_Error
(E
) then
7693 Set_Raises_Constraint_Error
(N
);
7696 -- If the result is not known at compile time, or is not of
7697 -- a scalar type, then the result is definitely not static,
7698 -- so we can quit now.
7700 if not Compile_Time_Known_Value
(E
)
7701 or else not Is_Scalar_Type
(Etype
(E
))
7703 -- An odd special case, if this is a Pos attribute, this
7704 -- is where we need to apply a range check since it does
7705 -- not get done anywhere else.
7707 if Id
= Attribute_Pos
then
7708 if Is_Integer_Type
(Etype
(E
)) then
7709 Apply_Range_Check
(E
, Etype
(N
));
7716 -- If the expression raises a constraint error, then so does
7717 -- the attribute reference. We keep going in this case because
7718 -- we are still interested in whether the attribute reference
7719 -- is static even if it is not static.
7721 elsif Raises_Constraint_Error
(E
) then
7722 Set_Raises_Constraint_Error
(N
);
7728 if Raises_Constraint_Error
(Prefix
(N
)) then
7729 Set_Is_Static_Expression
(N
, False);
7734 -- Deal with the case of a static attribute reference that raises
7735 -- constraint error. The Raises_Constraint_Error flag will already
7736 -- have been set, and the Static flag shows whether the attribute
7737 -- reference is static. In any case we certainly can't fold such an
7738 -- attribute reference.
7740 -- Note that the rewriting of the attribute node with the constraint
7741 -- error node is essential in this case, because otherwise Gigi might
7742 -- blow up on one of the attributes it never expects to see.
7744 -- The constraint_error node must have the type imposed by the context,
7745 -- to avoid spurious errors in the enclosing expression.
7747 if Raises_Constraint_Error
(N
) then
7749 Make_Raise_Constraint_Error
(Sloc
(N
),
7750 Reason
=> CE_Range_Check_Failed
);
7751 Set_Etype
(CE_Node
, Etype
(N
));
7752 Set_Raises_Constraint_Error
(CE_Node
);
7754 Rewrite
(N
, Relocate_Node
(CE_Node
));
7755 Set_Raises_Constraint_Error
(N
, True);
7759 -- At this point we have a potentially foldable attribute reference.
7760 -- If Static is set, then the attribute reference definitely obeys
7761 -- the requirements in (RM 4.9(7,8,22)), and it definitely can be
7762 -- folded. If Static is not set, then the attribute may or may not
7763 -- be foldable, and the individual attribute processing routines
7764 -- test Static as required in cases where it makes a difference.
7766 -- In the case where Static is not set, we do know that all the
7767 -- expressions present are at least known at compile time (we assumed
7768 -- above that if this was not the case, then there was no hope of static
7769 -- evaluation). However, we did not require that the bounds of the
7770 -- prefix type be compile time known, let alone static). That's because
7771 -- there are many attributes that can be computed at compile time on
7772 -- non-static subtypes, even though such references are not static
7775 -- For VAX float, the root type is an IEEE type. So make sure to use the
7776 -- base type instead of the root-type for floating point attributes.
7780 -- Attributes related to Ada 2012 iterators (placeholder ???)
7782 when Attribute_Constant_Indexing |
7783 Attribute_Default_Iterator |
7784 Attribute_Implicit_Dereference |
7785 Attribute_Iterator_Element |
7786 Attribute_Iterable |
7787 Attribute_Variable_Indexing
=> null;
7789 -- Internal attributes used to deal with Ada 2012 delayed aspects.
7790 -- These were already rejected by the parser. Thus they shouldn't
7793 when Internal_Attribute_Id
=>
7794 raise Program_Error
;
7800 when Attribute_Adjacent
=>
7804 (P_Base_Type
, Expr_Value_R
(E1
), Expr_Value_R
(E2
)),
7811 when Attribute_Aft
=>
7812 Fold_Uint
(N
, Aft_Value
(P_Type
), Static
);
7818 when Attribute_Alignment
=> Alignment_Block
: declare
7819 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
7822 -- Fold if alignment is set and not otherwise
7824 if Known_Alignment
(P_TypeA
) then
7825 Fold_Uint
(N
, Alignment
(P_TypeA
), Static
);
7827 end Alignment_Block
;
7829 -----------------------------
7830 -- Atomic_Always_Lock_Free --
7831 -----------------------------
7833 -- Atomic_Always_Lock_Free attribute is a Boolean, thus no need to fold
7836 when Attribute_Atomic_Always_Lock_Free
=> Atomic_Always_Lock_Free
:
7838 V
: constant Entity_Id
:=
7840 (Support_Atomic_Primitives_On_Target
7841 and then Support_Atomic_Primitives
(P_Type
));
7844 Rewrite
(N
, New_Occurrence_Of
(V
, Loc
));
7846 -- Analyze and resolve as boolean. Note that this attribute is a
7847 -- static attribute in GNAT.
7849 Analyze_And_Resolve
(N
, Standard_Boolean
);
7851 Set_Is_Static_Expression
(N
, True);
7852 end Atomic_Always_Lock_Free
;
7858 -- Bit can never be folded
7860 when Attribute_Bit
=>
7867 -- Body_version can never be static
7869 when Attribute_Body_Version
=>
7876 when Attribute_Ceiling
=>
7878 (N
, Eval_Fat
.Ceiling
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
7880 --------------------
7881 -- Component_Size --
7882 --------------------
7884 when Attribute_Component_Size
=>
7885 if Known_Static_Component_Size
(P_Type
) then
7886 Fold_Uint
(N
, Component_Size
(P_Type
), Static
);
7893 when Attribute_Compose
=>
7896 Eval_Fat
.Compose
(P_Base_Type
, Expr_Value_R
(E1
), Expr_Value
(E2
)),
7903 -- Constrained is never folded for now, there may be cases that
7904 -- could be handled at compile time. To be looked at later.
7906 when Attribute_Constrained
=>
7908 -- The expander might fold it and set the static flag accordingly,
7909 -- but with expansion disabled (as in ASIS), it remains as an
7910 -- attribute reference, and this reference is not static.
7912 Set_Is_Static_Expression
(N
, False);
7919 when Attribute_Copy_Sign
=>
7923 (P_Base_Type
, Expr_Value_R
(E1
), Expr_Value_R
(E2
)),
7930 when Attribute_Definite
=>
7931 Rewrite
(N
, New_Occurrence_Of
(
7932 Boolean_Literals
(Is_Definite_Subtype
(P_Entity
)), Loc
));
7933 Analyze_And_Resolve
(N
, Standard_Boolean
);
7939 when Attribute_Delta
=>
7940 Fold_Ureal
(N
, Delta_Value
(P_Type
), True);
7946 when Attribute_Denorm
=>
7948 (N
, UI_From_Int
(Boolean'Pos (Has_Denormals
(P_Type
))), Static
);
7950 ---------------------
7951 -- Descriptor_Size --
7952 ---------------------
7954 when Attribute_Descriptor_Size
=>
7961 when Attribute_Digits
=>
7962 Fold_Uint
(N
, Digits_Value
(P_Type
), Static
);
7968 when Attribute_Emax
=>
7970 -- Ada 83 attribute is defined as (RM83 3.5.8)
7972 -- T'Emax = 4 * T'Mantissa
7974 Fold_Uint
(N
, 4 * Mantissa
, Static
);
7980 when Attribute_Enum_Rep
=>
7982 -- For an enumeration type with a non-standard representation use
7983 -- the Enumeration_Rep field of the proper constant. Note that this
7984 -- will not work for types Character/Wide_[Wide-]Character, since no
7985 -- real entities are created for the enumeration literals, but that
7986 -- does not matter since these two types do not have non-standard
7987 -- representations anyway.
7989 if Is_Enumeration_Type
(P_Type
)
7990 and then Has_Non_Standard_Rep
(P_Type
)
7992 Fold_Uint
(N
, Enumeration_Rep
(Expr_Value_E
(E1
)), Static
);
7994 -- For enumeration types with standard representations and all
7995 -- other cases (i.e. all integer and modular types), Enum_Rep
7996 -- is equivalent to Pos.
7999 Fold_Uint
(N
, Expr_Value
(E1
), Static
);
8006 when Attribute_Enum_Val
=> Enum_Val
: declare
8010 -- We have something like Enum_Type'Enum_Val (23), so search for a
8011 -- corresponding value in the list of Enum_Rep values for the type.
8013 Lit
:= First_Literal
(P_Base_Type
);
8015 if Enumeration_Rep
(Lit
) = Expr_Value
(E1
) then
8016 Fold_Uint
(N
, Enumeration_Pos
(Lit
), Static
);
8023 Apply_Compile_Time_Constraint_Error
8024 (N
, "no representation value matches",
8025 CE_Range_Check_Failed
,
8026 Warn
=> not Static
);
8036 when Attribute_Epsilon
=>
8038 -- Ada 83 attribute is defined as (RM83 3.5.8)
8040 -- T'Epsilon = 2.0**(1 - T'Mantissa)
8042 Fold_Ureal
(N
, Ureal_2
** (1 - Mantissa
), True);
8048 when Attribute_Exponent
=>
8050 Eval_Fat
.Exponent
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8056 when Attribute_First
=> First_Attr
:
8060 if Compile_Time_Known_Value
(Lo_Bound
) then
8061 if Is_Real_Type
(P_Type
) then
8062 Fold_Ureal
(N
, Expr_Value_R
(Lo_Bound
), Static
);
8064 Fold_Uint
(N
, Expr_Value
(Lo_Bound
), Static
);
8068 Check_Concurrent_Discriminant
(Lo_Bound
);
8076 when Attribute_First_Valid
=> First_Valid
:
8078 if Has_Predicates
(P_Type
)
8079 and then Has_Static_Predicate
(P_Type
)
8082 FirstN
: constant Node_Id
:=
8083 First
(Static_Discrete_Predicate
(P_Type
));
8085 if Nkind
(FirstN
) = N_Range
then
8086 Fold_Uint
(N
, Expr_Value
(Low_Bound
(FirstN
)), Static
);
8088 Fold_Uint
(N
, Expr_Value
(FirstN
), Static
);
8094 Fold_Uint
(N
, Expr_Value
(Lo_Bound
), Static
);
8102 when Attribute_Fixed_Value
=>
8109 when Attribute_Floor
=>
8111 (N
, Eval_Fat
.Floor
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8117 when Attribute_Fore
=>
8118 if Compile_Time_Known_Bounds
(P_Type
) then
8119 Fold_Uint
(N
, UI_From_Int
(Fore_Value
), Static
);
8126 when Attribute_Fraction
=>
8128 (N
, Eval_Fat
.Fraction
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8130 -----------------------
8131 -- Has_Access_Values --
8132 -----------------------
8134 when Attribute_Has_Access_Values
=>
8135 Rewrite
(N
, New_Occurrence_Of
8136 (Boolean_Literals
(Has_Access_Values
(P_Root_Type
)), Loc
));
8137 Analyze_And_Resolve
(N
, Standard_Boolean
);
8139 -----------------------
8140 -- Has_Discriminants --
8141 -----------------------
8143 when Attribute_Has_Discriminants
=>
8144 Rewrite
(N
, New_Occurrence_Of
(
8145 Boolean_Literals
(Has_Discriminants
(P_Entity
)), Loc
));
8146 Analyze_And_Resolve
(N
, Standard_Boolean
);
8148 ----------------------
8149 -- Has_Same_Storage --
8150 ----------------------
8152 when Attribute_Has_Same_Storage
=>
8155 -----------------------
8156 -- Has_Tagged_Values --
8157 -----------------------
8159 when Attribute_Has_Tagged_Values
=>
8160 Rewrite
(N
, New_Occurrence_Of
8161 (Boolean_Literals
(Has_Tagged_Component
(P_Root_Type
)), Loc
));
8162 Analyze_And_Resolve
(N
, Standard_Boolean
);
8168 when Attribute_Identity
=>
8175 -- Image is a scalar attribute, but is never static, because it is
8176 -- not a static function (having a non-scalar argument (RM 4.9(22))
8177 -- However, we can constant-fold the image of an enumeration literal
8178 -- if names are available.
8180 when Attribute_Image
=>
8181 if Is_Entity_Name
(E1
)
8182 and then Ekind
(Entity
(E1
)) = E_Enumeration_Literal
8183 and then not Discard_Names
(First_Subtype
(Etype
(E1
)))
8184 and then not Global_Discard_Names
8187 Lit
: constant Entity_Id
:= Entity
(E1
);
8191 Get_Unqualified_Decoded_Name_String
(Chars
(Lit
));
8192 Set_Casing
(All_Upper_Case
);
8193 Store_String_Chars
(Name_Buffer
(1 .. Name_Len
));
8195 Rewrite
(N
, Make_String_Literal
(Loc
, Strval
=> Str
));
8196 Analyze_And_Resolve
(N
, Standard_String
);
8197 Set_Is_Static_Expression
(N
, False);
8205 -- We never try to fold Integer_Value (though perhaps we could???)
8207 when Attribute_Integer_Value
=>
8214 -- Invalid_Value is a scalar attribute that is never static, because
8215 -- the value is by design out of range.
8217 when Attribute_Invalid_Value
=>
8224 when Attribute_Large
=>
8226 -- For fixed-point, we use the identity:
8228 -- T'Large = (2.0**T'Mantissa - 1.0) * T'Small
8230 if Is_Fixed_Point_Type
(P_Type
) then
8232 Make_Op_Multiply
(Loc
,
8234 Make_Op_Subtract
(Loc
,
8238 Make_Real_Literal
(Loc
, Ureal_2
),
8240 Make_Attribute_Reference
(Loc
,
8242 Attribute_Name
=> Name_Mantissa
)),
8243 Right_Opnd
=> Make_Real_Literal
(Loc
, Ureal_1
)),
8246 Make_Real_Literal
(Loc
, Small_Value
(Entity
(P
)))));
8248 Analyze_And_Resolve
(N
, C_Type
);
8250 -- Floating-point (Ada 83 compatibility)
8253 -- Ada 83 attribute is defined as (RM83 3.5.8)
8255 -- T'Large = 2.0**T'Emax * (1.0 - 2.0**(-T'Mantissa))
8259 -- T'Emax = 4 * T'Mantissa
8263 Ureal_2
** (4 * Mantissa
) * (Ureal_1
- Ureal_2
** (-Mantissa
)),
8271 when Attribute_Lock_Free
=> Lock_Free
: declare
8272 V
: constant Entity_Id
:= Boolean_Literals
(Uses_Lock_Free
(P_Type
));
8275 Rewrite
(N
, New_Occurrence_Of
(V
, Loc
));
8277 -- Analyze and resolve as boolean. Note that this attribute is a
8278 -- static attribute in GNAT.
8280 Analyze_And_Resolve
(N
, Standard_Boolean
);
8282 Set_Is_Static_Expression
(N
, True);
8289 when Attribute_Last
=> Last_Attr
:
8293 if Compile_Time_Known_Value
(Hi_Bound
) then
8294 if Is_Real_Type
(P_Type
) then
8295 Fold_Ureal
(N
, Expr_Value_R
(Hi_Bound
), Static
);
8297 Fold_Uint
(N
, Expr_Value
(Hi_Bound
), Static
);
8301 Check_Concurrent_Discriminant
(Hi_Bound
);
8309 when Attribute_Last_Valid
=> Last_Valid
:
8311 if Has_Predicates
(P_Type
)
8312 and then Has_Static_Predicate
(P_Type
)
8315 LastN
: constant Node_Id
:=
8316 Last
(Static_Discrete_Predicate
(P_Type
));
8318 if Nkind
(LastN
) = N_Range
then
8319 Fold_Uint
(N
, Expr_Value
(High_Bound
(LastN
)), Static
);
8321 Fold_Uint
(N
, Expr_Value
(LastN
), Static
);
8327 Fold_Uint
(N
, Expr_Value
(Hi_Bound
), Static
);
8335 when Attribute_Leading_Part
=>
8338 Eval_Fat
.Leading_Part
8339 (P_Base_Type
, Expr_Value_R
(E1
), Expr_Value
(E2
)),
8346 when Attribute_Length
=> Length
: declare
8350 -- If any index type is a formal type, or derived from one, the
8351 -- bounds are not static. Treating them as static can produce
8352 -- spurious warnings or improper constant folding.
8354 Ind
:= First_Index
(P_Type
);
8355 while Present
(Ind
) loop
8356 if Is_Generic_Type
(Root_Type
(Etype
(Ind
))) then
8365 -- For two compile time values, we can compute length
8367 if Compile_Time_Known_Value
(Lo_Bound
)
8368 and then Compile_Time_Known_Value
(Hi_Bound
)
8371 UI_Max
(0, 1 + (Expr_Value
(Hi_Bound
) - Expr_Value
(Lo_Bound
))),
8375 -- One more case is where Hi_Bound and Lo_Bound are compile-time
8376 -- comparable, and we can figure out the difference between them.
8379 Diff
: aliased Uint
;
8383 Compile_Time_Compare
8384 (Lo_Bound
, Hi_Bound
, Diff
'Access, Assume_Valid
=> False)
8387 Fold_Uint
(N
, Uint_1
, Static
);
8390 Fold_Uint
(N
, Uint_0
, Static
);
8393 if Diff
/= No_Uint
then
8394 Fold_Uint
(N
, Diff
+ 1, Static
);
8407 -- Loop_Entry acts as an alias of a constant initialized to the prefix
8408 -- of the said attribute at the point of entry into the related loop. As
8409 -- such, the attribute reference does not need to be evaluated because
8410 -- the prefix is the one that is evaluted.
8412 when Attribute_Loop_Entry
=>
8419 when Attribute_Machine
=>
8423 (P_Base_Type
, Expr_Value_R
(E1
), Eval_Fat
.Round
, N
),
8430 when Attribute_Machine_Emax
=>
8431 Fold_Uint
(N
, Machine_Emax_Value
(P_Type
), Static
);
8437 when Attribute_Machine_Emin
=>
8438 Fold_Uint
(N
, Machine_Emin_Value
(P_Type
), Static
);
8440 ----------------------
8441 -- Machine_Mantissa --
8442 ----------------------
8444 when Attribute_Machine_Mantissa
=>
8445 Fold_Uint
(N
, Machine_Mantissa_Value
(P_Type
), Static
);
8447 -----------------------
8448 -- Machine_Overflows --
8449 -----------------------
8451 when Attribute_Machine_Overflows
=>
8453 -- Always true for fixed-point
8455 if Is_Fixed_Point_Type
(P_Type
) then
8456 Fold_Uint
(N
, True_Value
, Static
);
8458 -- Floating point case
8462 UI_From_Int
(Boolean'Pos (Machine_Overflows_On_Target
)),
8470 when Attribute_Machine_Radix
=>
8471 if Is_Fixed_Point_Type
(P_Type
) then
8472 if Is_Decimal_Fixed_Point_Type
(P_Type
)
8473 and then Machine_Radix_10
(P_Type
)
8475 Fold_Uint
(N
, Uint_10
, Static
);
8477 Fold_Uint
(N
, Uint_2
, Static
);
8480 -- All floating-point type always have radix 2
8483 Fold_Uint
(N
, Uint_2
, Static
);
8486 ----------------------
8487 -- Machine_Rounding --
8488 ----------------------
8490 -- Note: for the folding case, it is fine to treat Machine_Rounding
8491 -- exactly the same way as Rounding, since this is one of the allowed
8492 -- behaviors, and performance is not an issue here. It might be a bit
8493 -- better to give the same result as it would give at run time, even
8494 -- though the non-determinism is certainly permitted.
8496 when Attribute_Machine_Rounding
=>
8498 (N
, Eval_Fat
.Rounding
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8500 --------------------
8501 -- Machine_Rounds --
8502 --------------------
8504 when Attribute_Machine_Rounds
=>
8506 -- Always False for fixed-point
8508 if Is_Fixed_Point_Type
(P_Type
) then
8509 Fold_Uint
(N
, False_Value
, Static
);
8511 -- Else yield proper floating-point result
8515 (N
, UI_From_Int
(Boolean'Pos (Machine_Rounds_On_Target
)),
8523 -- Note: Machine_Size is identical to Object_Size
8525 when Attribute_Machine_Size
=> Machine_Size
: declare
8526 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
8529 if Known_Esize
(P_TypeA
) then
8530 Fold_Uint
(N
, Esize
(P_TypeA
), Static
);
8538 when Attribute_Mantissa
=>
8540 -- Fixed-point mantissa
8542 if Is_Fixed_Point_Type
(P_Type
) then
8544 -- Compile time foldable case
8546 if Compile_Time_Known_Value
(Type_Low_Bound
(P_Type
))
8548 Compile_Time_Known_Value
(Type_High_Bound
(P_Type
))
8550 -- The calculation of the obsolete Ada 83 attribute Mantissa
8551 -- is annoying, because of AI00143, quoted here:
8553 -- !question 84-01-10
8555 -- Consider the model numbers for F:
8557 -- type F is delta 1.0 range -7.0 .. 8.0;
8559 -- The wording requires that F'MANTISSA be the SMALLEST
8560 -- integer number for which each bound of the specified
8561 -- range is either a model number or lies at most small
8562 -- distant from a model number. This means F'MANTISSA
8563 -- is required to be 3 since the range -7.0 .. 7.0 fits
8564 -- in 3 signed bits, and 8 is "at most" 1.0 from a model
8565 -- number, namely, 7. Is this analysis correct? Note that
8566 -- this implies the upper bound of the range is not
8567 -- represented as a model number.
8569 -- !response 84-03-17
8571 -- The analysis is correct. The upper and lower bounds for
8572 -- a fixed point type can lie outside the range of model
8583 LBound
:= Expr_Value_R
(Type_Low_Bound
(P_Type
));
8584 UBound
:= Expr_Value_R
(Type_High_Bound
(P_Type
));
8585 Bound
:= UR_Max
(UR_Abs
(LBound
), UR_Abs
(UBound
));
8586 Max_Man
:= UR_Trunc
(Bound
/ Small_Value
(P_Type
));
8588 -- If the Bound is exactly a model number, i.e. a multiple
8589 -- of Small, then we back it off by one to get the integer
8590 -- value that must be representable.
8592 if Small_Value
(P_Type
) * Max_Man
= Bound
then
8593 Max_Man
:= Max_Man
- 1;
8596 -- Now find corresponding size = Mantissa value
8599 while 2 ** Siz
< Max_Man
loop
8603 Fold_Uint
(N
, Siz
, Static
);
8607 -- The case of dynamic bounds cannot be evaluated at compile
8608 -- time. Instead we use a runtime routine (see Exp_Attr).
8613 -- Floating-point Mantissa
8616 Fold_Uint
(N
, Mantissa
, Static
);
8623 when Attribute_Max
=> Max
:
8625 if Is_Real_Type
(P_Type
) then
8627 (N
, UR_Max
(Expr_Value_R
(E1
), Expr_Value_R
(E2
)), Static
);
8629 Fold_Uint
(N
, UI_Max
(Expr_Value
(E1
), Expr_Value
(E2
)), Static
);
8633 ----------------------------------
8634 -- Max_Alignment_For_Allocation --
8635 ----------------------------------
8637 -- Max_Alignment_For_Allocation is usually the Alignment. However,
8638 -- arrays are allocated with dope, so we need to take into account both
8639 -- the alignment of the array, which comes from the component alignment,
8640 -- and the alignment of the dope. Also, if the alignment is unknown, we
8641 -- use the max (it's OK to be pessimistic).
8643 when Attribute_Max_Alignment_For_Allocation
=>
8645 A
: Uint
:= UI_From_Int
(Ttypes
.Maximum_Alignment
);
8647 if Known_Alignment
(P_Type
) and then
8648 (not Is_Array_Type
(P_Type
) or else Alignment
(P_Type
) > A
)
8650 A
:= Alignment
(P_Type
);
8653 Fold_Uint
(N
, A
, Static
);
8656 ----------------------------------
8657 -- Max_Size_In_Storage_Elements --
8658 ----------------------------------
8660 -- Max_Size_In_Storage_Elements is simply the Size rounded up to a
8661 -- Storage_Unit boundary. We can fold any cases for which the size
8662 -- is known by the front end.
8664 when Attribute_Max_Size_In_Storage_Elements
=>
8665 if Known_Esize
(P_Type
) then
8667 (Esize
(P_Type
) + System_Storage_Unit
- 1) /
8668 System_Storage_Unit
,
8672 --------------------
8673 -- Mechanism_Code --
8674 --------------------
8676 when Attribute_Mechanism_Code
=>
8680 Mech
: Mechanism_Type
;
8684 Mech
:= Mechanism
(P_Entity
);
8687 Val
:= UI_To_Int
(Expr_Value
(E1
));
8689 Formal
:= First_Formal
(P_Entity
);
8690 for J
in 1 .. Val
- 1 loop
8691 Next_Formal
(Formal
);
8693 Mech
:= Mechanism
(Formal
);
8697 Fold_Uint
(N
, UI_From_Int
(Int
(-Mech
)), Static
);
8705 when Attribute_Min
=> Min
:
8707 if Is_Real_Type
(P_Type
) then
8709 (N
, UR_Min
(Expr_Value_R
(E1
), Expr_Value_R
(E2
)), Static
);
8712 (N
, UI_Min
(Expr_Value
(E1
), Expr_Value
(E2
)), Static
);
8720 when Attribute_Mod
=>
8722 (N
, UI_Mod
(Expr_Value
(E1
), Modulus
(P_Base_Type
)), Static
);
8728 when Attribute_Model
=>
8730 (N
, Eval_Fat
.Model
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8736 when Attribute_Model_Emin
=>
8737 Fold_Uint
(N
, Model_Emin_Value
(P_Base_Type
), Static
);
8743 when Attribute_Model_Epsilon
=>
8744 Fold_Ureal
(N
, Model_Epsilon_Value
(P_Base_Type
), Static
);
8746 --------------------
8747 -- Model_Mantissa --
8748 --------------------
8750 when Attribute_Model_Mantissa
=>
8751 Fold_Uint
(N
, Model_Mantissa_Value
(P_Base_Type
), Static
);
8757 when Attribute_Model_Small
=>
8758 Fold_Ureal
(N
, Model_Small_Value
(P_Base_Type
), Static
);
8764 when Attribute_Modulus
=>
8765 Fold_Uint
(N
, Modulus
(P_Type
), Static
);
8767 --------------------
8768 -- Null_Parameter --
8769 --------------------
8771 -- Cannot fold, we know the value sort of, but the whole point is
8772 -- that there is no way to talk about this imaginary value except
8773 -- by using the attribute, so we leave it the way it is.
8775 when Attribute_Null_Parameter
=>
8782 -- The Object_Size attribute for a type returns the Esize of the
8783 -- type and can be folded if this value is known.
8785 when Attribute_Object_Size
=> Object_Size
: declare
8786 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
8789 if Known_Esize
(P_TypeA
) then
8790 Fold_Uint
(N
, Esize
(P_TypeA
), Static
);
8794 ----------------------
8795 -- Overlaps_Storage --
8796 ----------------------
8798 when Attribute_Overlaps_Storage
=>
8801 -------------------------
8802 -- Passed_By_Reference --
8803 -------------------------
8805 -- Scalar types are never passed by reference
8807 when Attribute_Passed_By_Reference
=>
8808 Fold_Uint
(N
, False_Value
, Static
);
8814 when Attribute_Pos
=>
8815 Fold_Uint
(N
, Expr_Value
(E1
), Static
);
8821 when Attribute_Pred
=> Pred
:
8823 -- Floating-point case
8825 if Is_Floating_Point_Type
(P_Type
) then
8827 (N
, Eval_Fat
.Pred
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8831 elsif Is_Fixed_Point_Type
(P_Type
) then
8833 (N
, Expr_Value_R
(E1
) - Small_Value
(P_Type
), True);
8835 -- Modular integer case (wraps)
8837 elsif Is_Modular_Integer_Type
(P_Type
) then
8838 Fold_Uint
(N
, (Expr_Value
(E1
) - 1) mod Modulus
(P_Type
), Static
);
8840 -- Other scalar cases
8843 pragma Assert
(Is_Scalar_Type
(P_Type
));
8845 if Is_Enumeration_Type
(P_Type
)
8846 and then Expr_Value
(E1
) =
8847 Expr_Value
(Type_Low_Bound
(P_Base_Type
))
8849 Apply_Compile_Time_Constraint_Error
8850 (N
, "Pred of `&''First`",
8851 CE_Overflow_Check_Failed
,
8853 Warn
=> not Static
);
8859 Fold_Uint
(N
, Expr_Value
(E1
) - 1, Static
);
8867 -- No processing required, because by this stage, Range has been
8868 -- replaced by First .. Last, so this branch can never be taken.
8870 when Attribute_Range
=>
8871 raise Program_Error
;
8877 when Attribute_Range_Length
=>
8880 -- Can fold if both bounds are compile time known
8882 if Compile_Time_Known_Value
(Hi_Bound
)
8883 and then Compile_Time_Known_Value
(Lo_Bound
)
8887 (0, Expr_Value
(Hi_Bound
) - Expr_Value
(Lo_Bound
) + 1),
8891 -- One more case is where Hi_Bound and Lo_Bound are compile-time
8892 -- comparable, and we can figure out the difference between them.
8895 Diff
: aliased Uint
;
8899 Compile_Time_Compare
8900 (Lo_Bound
, Hi_Bound
, Diff
'Access, Assume_Valid
=> False)
8903 Fold_Uint
(N
, Uint_1
, Static
);
8906 Fold_Uint
(N
, Uint_0
, Static
);
8909 if Diff
/= No_Uint
then
8910 Fold_Uint
(N
, Diff
+ 1, Static
);
8922 when Attribute_Ref
=>
8923 Fold_Uint
(N
, Expr_Value
(E1
), Static
);
8929 when Attribute_Remainder
=> Remainder
: declare
8930 X
: constant Ureal
:= Expr_Value_R
(E1
);
8931 Y
: constant Ureal
:= Expr_Value_R
(E2
);
8934 if UR_Is_Zero
(Y
) then
8935 Apply_Compile_Time_Constraint_Error
8936 (N
, "division by zero in Remainder",
8937 CE_Overflow_Check_Failed
,
8938 Warn
=> not Static
);
8944 Fold_Ureal
(N
, Eval_Fat
.Remainder
(P_Base_Type
, X
, Y
), Static
);
8951 when Attribute_Restriction_Set
=> Restriction_Set
: declare
8953 Rewrite
(N
, New_Occurrence_Of
(Standard_False
, Loc
));
8954 Set_Is_Static_Expression
(N
);
8955 end Restriction_Set
;
8961 when Attribute_Round
=> Round
:
8967 -- First we get the (exact result) in units of small
8969 Sr
:= Expr_Value_R
(E1
) / Small_Value
(C_Type
);
8971 -- Now round that exactly to an integer
8973 Si
:= UR_To_Uint
(Sr
);
8975 -- Finally the result is obtained by converting back to real
8977 Fold_Ureal
(N
, Si
* Small_Value
(C_Type
), Static
);
8984 when Attribute_Rounding
=>
8986 (N
, Eval_Fat
.Rounding
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8992 when Attribute_Safe_Emax
=>
8993 Fold_Uint
(N
, Safe_Emax_Value
(P_Type
), Static
);
8999 when Attribute_Safe_First
=>
9000 Fold_Ureal
(N
, Safe_First_Value
(P_Type
), Static
);
9006 when Attribute_Safe_Large
=>
9007 if Is_Fixed_Point_Type
(P_Type
) then
9009 (N
, Expr_Value_R
(Type_High_Bound
(P_Base_Type
)), Static
);
9011 Fold_Ureal
(N
, Safe_Last_Value
(P_Type
), Static
);
9018 when Attribute_Safe_Last
=>
9019 Fold_Ureal
(N
, Safe_Last_Value
(P_Type
), Static
);
9025 when Attribute_Safe_Small
=>
9027 -- In Ada 95, the old Ada 83 attribute Safe_Small is redundant
9028 -- for fixed-point, since is the same as Small, but we implement
9029 -- it for backwards compatibility.
9031 if Is_Fixed_Point_Type
(P_Type
) then
9032 Fold_Ureal
(N
, Small_Value
(P_Type
), Static
);
9034 -- Ada 83 Safe_Small for floating-point cases
9037 Fold_Ureal
(N
, Model_Small_Value
(P_Type
), Static
);
9044 when Attribute_Scale
=>
9045 Fold_Uint
(N
, Scale_Value
(P_Type
), Static
);
9051 when Attribute_Scaling
=>
9055 (P_Base_Type
, Expr_Value_R
(E1
), Expr_Value
(E2
)),
9062 when Attribute_Signed_Zeros
=>
9064 (N
, UI_From_Int
(Boolean'Pos (Has_Signed_Zeros
(P_Type
))), Static
);
9070 -- Size attribute returns the RM size. All scalar types can be folded,
9071 -- as well as any types for which the size is known by the front end,
9072 -- including any type for which a size attribute is specified. This is
9073 -- one of the places where it is annoying that a size of zero means two
9074 -- things (zero size for scalars, unspecified size for non-scalars).
9076 when Attribute_Size | Attribute_VADS_Size
=> Size
: declare
9077 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
9080 if Is_Scalar_Type
(P_TypeA
) or else RM_Size
(P_TypeA
) /= Uint_0
then
9084 if Id
= Attribute_VADS_Size
or else Use_VADS_Size
then
9086 S
: constant Node_Id
:= Size_Clause
(P_TypeA
);
9089 -- If a size clause applies, then use the size from it.
9090 -- This is one of the rare cases where we can use the
9091 -- Size_Clause field for a subtype when Has_Size_Clause
9092 -- is False. Consider:
9094 -- type x is range 1 .. 64;
9095 -- for x'size use 12;
9096 -- subtype y is x range 0 .. 3;
9098 -- Here y has a size clause inherited from x, but normally
9099 -- it does not apply, and y'size is 2. However, y'VADS_Size
9100 -- is indeed 12 and not 2.
9103 and then Is_OK_Static_Expression
(Expression
(S
))
9105 Fold_Uint
(N
, Expr_Value
(Expression
(S
)), Static
);
9107 -- If no size is specified, then we simply use the object
9108 -- size in the VADS_Size case (e.g. Natural'Size is equal
9109 -- to Integer'Size, not one less).
9112 Fold_Uint
(N
, Esize
(P_TypeA
), Static
);
9116 -- Normal case (Size) in which case we want the RM_Size
9119 Fold_Uint
(N
, RM_Size
(P_TypeA
), Static
);
9128 when Attribute_Small
=>
9130 -- The floating-point case is present only for Ada 83 compatibility.
9131 -- Note that strictly this is an illegal addition, since we are
9132 -- extending an Ada 95 defined attribute, but we anticipate an
9133 -- ARG ruling that will permit this.
9135 if Is_Floating_Point_Type
(P_Type
) then
9137 -- Ada 83 attribute is defined as (RM83 3.5.8)
9139 -- T'Small = 2.0**(-T'Emax - 1)
9143 -- T'Emax = 4 * T'Mantissa
9145 Fold_Ureal
(N
, Ureal_2
** ((-(4 * Mantissa
)) - 1), Static
);
9147 -- Normal Ada 95 fixed-point case
9150 Fold_Ureal
(N
, Small_Value
(P_Type
), True);
9157 when Attribute_Stream_Size
=>
9164 when Attribute_Succ
=> Succ
:
9166 -- Floating-point case
9168 if Is_Floating_Point_Type
(P_Type
) then
9170 (N
, Eval_Fat
.Succ
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
9174 elsif Is_Fixed_Point_Type
(P_Type
) then
9175 Fold_Ureal
(N
, Expr_Value_R
(E1
) + Small_Value
(P_Type
), Static
);
9177 -- Modular integer case (wraps)
9179 elsif Is_Modular_Integer_Type
(P_Type
) then
9180 Fold_Uint
(N
, (Expr_Value
(E1
) + 1) mod Modulus
(P_Type
), Static
);
9182 -- Other scalar cases
9185 pragma Assert
(Is_Scalar_Type
(P_Type
));
9187 if Is_Enumeration_Type
(P_Type
)
9188 and then Expr_Value
(E1
) =
9189 Expr_Value
(Type_High_Bound
(P_Base_Type
))
9191 Apply_Compile_Time_Constraint_Error
9192 (N
, "Succ of `&''Last`",
9193 CE_Overflow_Check_Failed
,
9195 Warn
=> not Static
);
9200 Fold_Uint
(N
, Expr_Value
(E1
) + 1, Static
);
9209 when Attribute_Truncation
=>
9212 Eval_Fat
.Truncation
(P_Base_Type
, Expr_Value_R
(E1
)),
9219 when Attribute_Type_Class
=> Type_Class
: declare
9220 Typ
: constant Entity_Id
:= Underlying_Type
(P_Base_Type
);
9224 if Is_Descendent_Of_Address
(Typ
) then
9225 Id
:= RE_Type_Class_Address
;
9227 elsif Is_Enumeration_Type
(Typ
) then
9228 Id
:= RE_Type_Class_Enumeration
;
9230 elsif Is_Integer_Type
(Typ
) then
9231 Id
:= RE_Type_Class_Integer
;
9233 elsif Is_Fixed_Point_Type
(Typ
) then
9234 Id
:= RE_Type_Class_Fixed_Point
;
9236 elsif Is_Floating_Point_Type
(Typ
) then
9237 Id
:= RE_Type_Class_Floating_Point
;
9239 elsif Is_Array_Type
(Typ
) then
9240 Id
:= RE_Type_Class_Array
;
9242 elsif Is_Record_Type
(Typ
) then
9243 Id
:= RE_Type_Class_Record
;
9245 elsif Is_Access_Type
(Typ
) then
9246 Id
:= RE_Type_Class_Access
;
9248 elsif Is_Enumeration_Type
(Typ
) then
9249 Id
:= RE_Type_Class_Enumeration
;
9251 elsif Is_Task_Type
(Typ
) then
9252 Id
:= RE_Type_Class_Task
;
9254 -- We treat protected types like task types. It would make more
9255 -- sense to have another enumeration value, but after all the
9256 -- whole point of this feature is to be exactly DEC compatible,
9257 -- and changing the type Type_Class would not meet this requirement.
9259 elsif Is_Protected_Type
(Typ
) then
9260 Id
:= RE_Type_Class_Task
;
9262 -- Not clear if there are any other possibilities, but if there
9263 -- are, then we will treat them as the address case.
9266 Id
:= RE_Type_Class_Address
;
9269 Rewrite
(N
, New_Occurrence_Of
(RTE
(Id
), Loc
));
9272 -----------------------
9273 -- Unbiased_Rounding --
9274 -----------------------
9276 when Attribute_Unbiased_Rounding
=>
9279 Eval_Fat
.Unbiased_Rounding
(P_Base_Type
, Expr_Value_R
(E1
)),
9282 -------------------------
9283 -- Unconstrained_Array --
9284 -------------------------
9286 when Attribute_Unconstrained_Array
=> Unconstrained_Array
: declare
9287 Typ
: constant Entity_Id
:= Underlying_Type
(P_Type
);
9290 Rewrite
(N
, New_Occurrence_Of
(
9292 Is_Array_Type
(P_Type
)
9293 and then not Is_Constrained
(Typ
)), Loc
));
9295 -- Analyze and resolve as boolean, note that this attribute is
9296 -- a static attribute in GNAT.
9298 Analyze_And_Resolve
(N
, Standard_Boolean
);
9300 Set_Is_Static_Expression
(N
, True);
9301 end Unconstrained_Array
;
9303 -- Attribute Update is never static
9305 when Attribute_Update
=>
9312 -- Processing is shared with Size
9318 when Attribute_Val
=> Val
:
9320 if Expr_Value
(E1
) < Expr_Value
(Type_Low_Bound
(P_Base_Type
))
9322 Expr_Value
(E1
) > Expr_Value
(Type_High_Bound
(P_Base_Type
))
9324 Apply_Compile_Time_Constraint_Error
9325 (N
, "Val expression out of range",
9326 CE_Range_Check_Failed
,
9327 Warn
=> not Static
);
9333 Fold_Uint
(N
, Expr_Value
(E1
), Static
);
9341 -- The Value_Size attribute for a type returns the RM size of the type.
9342 -- This an always be folded for scalar types, and can also be folded for
9343 -- non-scalar types if the size is set. This is one of the places where
9344 -- it is annoying that a size of zero means two things!
9346 when Attribute_Value_Size
=> Value_Size
: declare
9347 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
9349 if Is_Scalar_Type
(P_TypeA
) or else RM_Size
(P_TypeA
) /= Uint_0
then
9350 Fold_Uint
(N
, RM_Size
(P_TypeA
), Static
);
9358 -- Version can never be static
9360 when Attribute_Version
=>
9367 -- Wide_Image is a scalar attribute, but is never static, because it
9368 -- is not a static function (having a non-scalar argument (RM 4.9(22))
9370 when Attribute_Wide_Image
=>
9373 ---------------------
9374 -- Wide_Wide_Image --
9375 ---------------------
9377 -- Wide_Wide_Image is a scalar attribute but is never static, because it
9378 -- is not a static function (having a non-scalar argument (RM 4.9(22)).
9380 when Attribute_Wide_Wide_Image
=>
9383 ---------------------
9384 -- Wide_Wide_Width --
9385 ---------------------
9387 -- Processing for Wide_Wide_Width is combined with Width
9393 -- Processing for Wide_Width is combined with Width
9399 -- This processing also handles the case of Wide_[Wide_]Width
9401 when Attribute_Width |
9402 Attribute_Wide_Width |
9403 Attribute_Wide_Wide_Width
=> Width
:
9405 if Compile_Time_Known_Bounds
(P_Type
) then
9407 -- Floating-point types
9409 if Is_Floating_Point_Type
(P_Type
) then
9411 -- Width is zero for a null range (RM 3.5 (38))
9413 if Expr_Value_R
(Type_High_Bound
(P_Type
)) <
9414 Expr_Value_R
(Type_Low_Bound
(P_Type
))
9416 Fold_Uint
(N
, Uint_0
, Static
);
9419 -- For floating-point, we have +N.dddE+nnn where length
9420 -- of ddd is determined by type'Digits - 1, but is one
9421 -- if Digits is one (RM 3.5 (33)).
9423 -- nnn is set to 2 for Short_Float and Float (32 bit
9424 -- floats), and 3 for Long_Float and Long_Long_Float.
9425 -- For machines where Long_Long_Float is the IEEE
9426 -- extended precision type, the exponent takes 4 digits.
9430 Int
'Max (2, UI_To_Int
(Digits_Value
(P_Type
)));
9433 if Esize
(P_Type
) <= 32 then
9435 elsif Esize
(P_Type
) = 64 then
9441 Fold_Uint
(N
, UI_From_Int
(Len
), Static
);
9445 -- Fixed-point types
9447 elsif Is_Fixed_Point_Type
(P_Type
) then
9449 -- Width is zero for a null range (RM 3.5 (38))
9451 if Expr_Value
(Type_High_Bound
(P_Type
)) <
9452 Expr_Value
(Type_Low_Bound
(P_Type
))
9454 Fold_Uint
(N
, Uint_0
, Static
);
9456 -- The non-null case depends on the specific real type
9459 -- For fixed-point type width is Fore + 1 + Aft (RM 3.5(34))
9462 (N
, UI_From_Int
(Fore_Value
+ 1) + Aft_Value
(P_Type
),
9470 R
: constant Entity_Id
:= Root_Type
(P_Type
);
9471 Lo
: constant Uint
:= Expr_Value
(Type_Low_Bound
(P_Type
));
9472 Hi
: constant Uint
:= Expr_Value
(Type_High_Bound
(P_Type
));
9485 -- Width for types derived from Standard.Character
9486 -- and Standard.Wide_[Wide_]Character.
9488 elsif Is_Standard_Character_Type
(P_Type
) then
9491 -- Set W larger if needed
9493 for J
in UI_To_Int
(Lo
) .. UI_To_Int
(Hi
) loop
9495 -- All wide characters look like Hex_hhhhhhhh
9499 -- No need to compute this more than once
9504 C
:= Character'Val (J
);
9506 -- Test for all cases where Character'Image
9507 -- yields an image that is longer than three
9508 -- characters. First the cases of Reserved_xxx
9509 -- names (length = 12).
9512 when Reserved_128 | Reserved_129 |
9513 Reserved_132 | Reserved_153
9516 when BS | HT | LF | VT | FF | CR |
9517 SO | SI | EM | FS | GS | RS |
9518 US | RI | MW | ST | PM
9521 when NUL | SOH | STX | ETX | EOT |
9522 ENQ | ACK | BEL | DLE | DC1 |
9523 DC2 | DC3 | DC4 | NAK | SYN |
9524 ETB | CAN | SUB | ESC | DEL |
9525 BPH | NBH | NEL | SSA | ESA |
9526 HTS | HTJ | VTS | PLD | PLU |
9527 SS2 | SS3 | DCS | PU1 | PU2 |
9528 STS | CCH | SPA | EPA | SOS |
9529 SCI | CSI | OSC | APC
9532 when Space
.. Tilde |
9533 No_Break_Space
.. LC_Y_Diaeresis
9535 -- Special case of soft hyphen in Ada 2005
9537 if C
= Character'Val (16#AD#
)
9538 and then Ada_Version
>= Ada_2005
9546 W
:= Int
'Max (W
, Wt
);
9550 -- Width for types derived from Standard.Boolean
9552 elsif R
= Standard_Boolean
then
9559 -- Width for integer types
9561 elsif Is_Integer_Type
(P_Type
) then
9562 T
:= UI_Max
(abs Lo
, abs Hi
);
9570 -- User declared enum type with discard names
9572 elsif Discard_Names
(R
) then
9574 -- If range is null, result is zero, that has already
9575 -- been dealt with, so what we need is the power of ten
9576 -- that accomodates the Pos of the largest value, which
9577 -- is the high bound of the range + one for the space.
9586 -- Only remaining possibility is user declared enum type
9587 -- with normal case of Discard_Names not active.
9590 pragma Assert
(Is_Enumeration_Type
(P_Type
));
9593 L
:= First_Literal
(P_Type
);
9594 while Present
(L
) loop
9596 -- Only pay attention to in range characters
9598 if Lo
<= Enumeration_Pos
(L
)
9599 and then Enumeration_Pos
(L
) <= Hi
9601 -- For Width case, use decoded name
9603 if Id
= Attribute_Width
then
9604 Get_Decoded_Name_String
(Chars
(L
));
9605 Wt
:= Nat
(Name_Len
);
9607 -- For Wide_[Wide_]Width, use encoded name, and
9608 -- then adjust for the encoding.
9611 Get_Name_String
(Chars
(L
));
9613 -- Character literals are always of length 3
9615 if Name_Buffer
(1) = 'Q' then
9618 -- Otherwise loop to adjust for upper/wide chars
9621 Wt
:= Nat
(Name_Len
);
9623 for J
in 1 .. Name_Len
loop
9624 if Name_Buffer
(J
) = 'U' then
9626 elsif Name_Buffer
(J
) = 'W' then
9633 W
:= Int
'Max (W
, Wt
);
9640 Fold_Uint
(N
, UI_From_Int
(W
), Static
);
9646 -- The following attributes denote functions that cannot be folded
9648 when Attribute_From_Any |
9650 Attribute_TypeCode
=>
9653 -- The following attributes can never be folded, and furthermore we
9654 -- should not even have entered the case statement for any of these.
9655 -- Note that in some cases, the values have already been folded as
9656 -- a result of the processing in Analyze_Attribute or earlier in
9659 when Attribute_Abort_Signal |
9662 Attribute_Address_Size |
9663 Attribute_Asm_Input |
9664 Attribute_Asm_Output |
9666 Attribute_Bit_Order |
9667 Attribute_Bit_Position |
9668 Attribute_Callable |
9671 Attribute_Code_Address |
9672 Attribute_Compiler_Version |
9674 Attribute_Default_Bit_Order |
9675 Attribute_Default_Scalar_Storage_Order |
9677 Attribute_Elaborated |
9678 Attribute_Elab_Body |
9679 Attribute_Elab_Spec |
9680 Attribute_Elab_Subp_Body |
9682 Attribute_External_Tag |
9683 Attribute_Fast_Math |
9684 Attribute_First_Bit |
9687 Attribute_Last_Bit |
9688 Attribute_Library_Level |
9689 Attribute_Maximum_Alignment |
9692 Attribute_Partition_ID |
9693 Attribute_Pool_Address |
9694 Attribute_Position |
9695 Attribute_Priority |
9698 Attribute_Scalar_Storage_Order |
9699 Attribute_Simple_Storage_Pool |
9700 Attribute_Storage_Pool |
9701 Attribute_Storage_Size |
9702 Attribute_Storage_Unit |
9703 Attribute_Stub_Type |
9704 Attribute_System_Allocator_Alignment |
9706 Attribute_Target_Name |
9707 Attribute_Terminated |
9708 Attribute_To_Address |
9709 Attribute_Type_Key |
9710 Attribute_UET_Address |
9711 Attribute_Unchecked_Access |
9712 Attribute_Universal_Literal_String |
9713 Attribute_Unrestricted_Access |
9715 Attribute_Valid_Scalars |
9717 Attribute_Wchar_T_Size |
9718 Attribute_Wide_Value |
9719 Attribute_Wide_Wide_Value |
9720 Attribute_Word_Size |
9723 raise Program_Error
;
9726 -- At the end of the case, one more check. If we did a static evaluation
9727 -- so that the result is now a literal, then set Is_Static_Expression
9728 -- in the constant only if the prefix type is a static subtype. For
9729 -- non-static subtypes, the folding is still OK, but not static.
9731 -- An exception is the GNAT attribute Constrained_Array which is
9732 -- defined to be a static attribute in all cases.
9734 if Nkind_In
(N
, N_Integer_Literal
,
9736 N_Character_Literal
,
9738 or else (Is_Entity_Name
(N
)
9739 and then Ekind
(Entity
(N
)) = E_Enumeration_Literal
)
9741 Set_Is_Static_Expression
(N
, Static
);
9743 -- If this is still an attribute reference, then it has not been folded
9744 -- and that means that its expressions are in a non-static context.
9746 elsif Nkind
(N
) = N_Attribute_Reference
then
9749 -- Note: the else case not covered here are odd cases where the
9750 -- processing has transformed the attribute into something other
9751 -- than a constant. Nothing more to do in such cases.
9758 ------------------------------
9759 -- Is_Anonymous_Tagged_Base --
9760 ------------------------------
9762 function Is_Anonymous_Tagged_Base
9764 Typ
: Entity_Id
) return Boolean
9768 Anon
= Current_Scope
9769 and then Is_Itype
(Anon
)
9770 and then Associated_Node_For_Itype
(Anon
) = Parent
(Typ
);
9771 end Is_Anonymous_Tagged_Base
;
9773 --------------------------------
9774 -- Name_Implies_Lvalue_Prefix --
9775 --------------------------------
9777 function Name_Implies_Lvalue_Prefix
(Nam
: Name_Id
) return Boolean is
9778 pragma Assert
(Is_Attribute_Name
(Nam
));
9780 return Attribute_Name_Implies_Lvalue_Prefix
(Get_Attribute_Id
(Nam
));
9781 end Name_Implies_Lvalue_Prefix
;
9783 -----------------------
9784 -- Resolve_Attribute --
9785 -----------------------
9787 procedure Resolve_Attribute
(N
: Node_Id
; Typ
: Entity_Id
) is
9788 Loc
: constant Source_Ptr
:= Sloc
(N
);
9789 P
: constant Node_Id
:= Prefix
(N
);
9790 Aname
: constant Name_Id
:= Attribute_Name
(N
);
9791 Attr_Id
: constant Attribute_Id
:= Get_Attribute_Id
(Aname
);
9792 Btyp
: constant Entity_Id
:= Base_Type
(Typ
);
9793 Des_Btyp
: Entity_Id
;
9794 Index
: Interp_Index
;
9796 Nom_Subt
: Entity_Id
;
9798 procedure Accessibility_Message
;
9799 -- Error, or warning within an instance, if the static accessibility
9800 -- rules of 3.10.2 are violated.
9802 function Declared_Within_Generic_Unit
9803 (Entity
: Entity_Id
;
9804 Generic_Unit
: Node_Id
) return Boolean;
9805 -- Returns True if Declared_Entity is declared within the declarative
9806 -- region of Generic_Unit; otherwise returns False.
9808 ---------------------------
9809 -- Accessibility_Message --
9810 ---------------------------
9812 procedure Accessibility_Message
is
9813 Indic
: Node_Id
:= Parent
(Parent
(N
));
9816 -- In an instance, this is a runtime check, but one we
9817 -- know will fail, so generate an appropriate warning.
9819 if In_Instance_Body
then
9820 Error_Msg_Warn
:= SPARK_Mode
/= On
;
9822 ("non-local pointer cannot point to local object<<", P
);
9823 Error_Msg_F
("\Program_Error [<<", P
);
9825 Make_Raise_Program_Error
(Loc
,
9826 Reason
=> PE_Accessibility_Check_Failed
));
9831 Error_Msg_F
("non-local pointer cannot point to local object", P
);
9833 -- Check for case where we have a missing access definition
9835 if Is_Record_Type
(Current_Scope
)
9837 Nkind_In
(Parent
(N
), N_Discriminant_Association
,
9838 N_Index_Or_Discriminant_Constraint
)
9840 Indic
:= Parent
(Parent
(N
));
9841 while Present
(Indic
)
9842 and then Nkind
(Indic
) /= N_Subtype_Indication
9844 Indic
:= Parent
(Indic
);
9847 if Present
(Indic
) then
9849 ("\use an access definition for" &
9850 " the access discriminant of&",
9851 N
, Entity
(Subtype_Mark
(Indic
)));
9855 end Accessibility_Message
;
9857 ----------------------------------
9858 -- Declared_Within_Generic_Unit --
9859 ----------------------------------
9861 function Declared_Within_Generic_Unit
9862 (Entity
: Entity_Id
;
9863 Generic_Unit
: Node_Id
) return Boolean
9865 Generic_Encloser
: Node_Id
:= Enclosing_Generic_Unit
(Entity
);
9868 while Present
(Generic_Encloser
) loop
9869 if Generic_Encloser
= Generic_Unit
then
9873 -- We have to step to the scope of the generic's entity, because
9874 -- otherwise we'll just get back the same generic.
9877 Enclosing_Generic_Unit
9878 (Scope
(Defining_Entity
(Generic_Encloser
)));
9882 end Declared_Within_Generic_Unit
;
9884 -- Start of processing for Resolve_Attribute
9887 -- If error during analysis, no point in continuing, except for array
9888 -- types, where we get better recovery by using unconstrained indexes
9889 -- than nothing at all (see Check_Array_Type).
9892 and then Attr_Id
/= Attribute_First
9893 and then Attr_Id
/= Attribute_Last
9894 and then Attr_Id
/= Attribute_Length
9895 and then Attr_Id
/= Attribute_Range
9900 -- If attribute was universal type, reset to actual type
9902 if Etype
(N
) = Universal_Integer
9903 or else Etype
(N
) = Universal_Real
9908 -- Remaining processing depends on attribute
9916 -- For access attributes, if the prefix denotes an entity, it is
9917 -- interpreted as a name, never as a call. It may be overloaded,
9918 -- in which case resolution uses the profile of the context type.
9919 -- Otherwise prefix must be resolved.
9921 when Attribute_Access
9922 | Attribute_Unchecked_Access
9923 | Attribute_Unrestricted_Access
=>
9927 -- Note possible modification if we have a variable
9929 if Is_Variable
(P
) then
9931 PN
: constant Node_Id
:= Parent
(N
);
9934 Note
: Boolean := True;
9935 -- Skip this for the case of Unrestricted_Access occuring in
9936 -- the context of a Valid check, since this otherwise leads
9937 -- to a missed warning (the Valid check does not really
9938 -- modify!) If this case, Note will be reset to False.
9941 if Attr_Id
= Attribute_Unrestricted_Access
9942 and then Nkind
(PN
) = N_Function_Call
9946 if Nkind
(Nm
) = N_Expanded_Name
9947 and then Chars
(Nm
) = Name_Valid
9948 and then Nkind
(Prefix
(Nm
)) = N_Identifier
9949 and then Chars
(Prefix
(Nm
)) = Name_Attr_Long_Float
9956 Note_Possible_Modification
(P
, Sure
=> False);
9961 -- The following comes from a query concerning improper use of
9962 -- universal_access in equality tests involving anonymous access
9963 -- types. Another good reason for 'Ref, but for now disable the
9964 -- test, which breaks several filed tests???
9966 if Ekind
(Typ
) = E_Anonymous_Access_Type
9967 and then Nkind_In
(Parent
(N
), N_Op_Eq
, N_Op_Ne
)
9970 Error_Msg_N
("need unique type to resolve 'Access", N
);
9971 Error_Msg_N
("\qualify attribute with some access type", N
);
9974 -- Case where prefix is an entity name
9976 if Is_Entity_Name
(P
) then
9978 -- Deal with case where prefix itself is overloaded
9980 if Is_Overloaded
(P
) then
9981 Get_First_Interp
(P
, Index
, It
);
9982 while Present
(It
.Nam
) loop
9983 if Type_Conformant
(Designated_Type
(Typ
), It
.Nam
) then
9984 Set_Entity
(P
, It
.Nam
);
9986 -- The prefix is definitely NOT overloaded anymore at
9987 -- this point, so we reset the Is_Overloaded flag to
9988 -- avoid any confusion when reanalyzing the node.
9990 Set_Is_Overloaded
(P
, False);
9991 Set_Is_Overloaded
(N
, False);
9992 Generate_Reference
(Entity
(P
), P
);
9996 Get_Next_Interp
(Index
, It
);
9999 -- If Prefix is a subprogram name, this reference freezes:
10001 -- If it is a type, there is nothing to resolve.
10002 -- If it is an object, complete its resolution.
10004 elsif Is_Overloadable
(Entity
(P
)) then
10006 -- Avoid insertion of freeze actions in spec expression mode
10008 if not In_Spec_Expression
then
10009 Freeze_Before
(N
, Entity
(P
));
10012 -- Nothing to do if prefix is a type name
10014 elsif Is_Type
(Entity
(P
)) then
10017 -- Otherwise non-overloaded other case, resolve the prefix
10023 -- Some further error checks
10025 Error_Msg_Name_1
:= Aname
;
10027 if not Is_Entity_Name
(P
) then
10030 elsif Is_Overloadable
(Entity
(P
))
10031 and then Is_Abstract_Subprogram
(Entity
(P
))
10033 Error_Msg_F
("prefix of % attribute cannot be abstract", P
);
10034 Set_Etype
(N
, Any_Type
);
10036 elsif Ekind
(Entity
(P
)) = E_Enumeration_Literal
then
10038 ("prefix of % attribute cannot be enumeration literal", P
);
10039 Set_Etype
(N
, Any_Type
);
10041 -- An attempt to take 'Access of a function that renames an
10042 -- enumeration literal. Issue a specialized error message.
10044 elsif Ekind
(Entity
(P
)) = E_Function
10045 and then Present
(Alias
(Entity
(P
)))
10046 and then Ekind
(Alias
(Entity
(P
))) = E_Enumeration_Literal
10049 ("prefix of % attribute cannot be function renaming "
10050 & "an enumeration literal", P
);
10051 Set_Etype
(N
, Any_Type
);
10053 elsif Convention
(Entity
(P
)) = Convention_Intrinsic
then
10054 Error_Msg_F
("prefix of % attribute cannot be intrinsic", P
);
10055 Set_Etype
(N
, Any_Type
);
10058 -- Assignments, return statements, components of aggregates,
10059 -- generic instantiations will require convention checks if
10060 -- the type is an access to subprogram. Given that there will
10061 -- also be accessibility checks on those, this is where the
10062 -- checks can eventually be centralized ???
10064 if Ekind_In
(Btyp
, E_Access_Subprogram_Type
,
10065 E_Anonymous_Access_Subprogram_Type
,
10066 E_Access_Protected_Subprogram_Type
,
10067 E_Anonymous_Access_Protected_Subprogram_Type
)
10069 -- Deal with convention mismatch
10071 if Convention
(Designated_Type
(Btyp
)) /=
10072 Convention
(Entity
(P
))
10075 ("subprogram & has wrong convention", P
, Entity
(P
));
10076 Error_Msg_Sloc
:= Sloc
(Btyp
);
10077 Error_Msg_FE
("\does not match & declared#", P
, Btyp
);
10079 if not Is_Itype
(Btyp
)
10080 and then not Has_Convention_Pragma
(Btyp
)
10083 ("\probable missing pragma Convention for &",
10088 Check_Subtype_Conformant
10089 (New_Id
=> Entity
(P
),
10090 Old_Id
=> Designated_Type
(Btyp
),
10094 if Attr_Id
= Attribute_Unchecked_Access
then
10095 Error_Msg_Name_1
:= Aname
;
10097 ("attribute% cannot be applied to a subprogram", P
);
10099 elsif Aname
= Name_Unrestricted_Access
then
10100 null; -- Nothing to check
10102 -- Check the static accessibility rule of 3.10.2(32).
10103 -- This rule also applies within the private part of an
10104 -- instantiation. This rule does not apply to anonymous
10105 -- access-to-subprogram types in access parameters.
10107 elsif Attr_Id
= Attribute_Access
10108 and then not In_Instance_Body
10110 (Ekind
(Btyp
) = E_Access_Subprogram_Type
10111 or else Is_Local_Anonymous_Access
(Btyp
))
10112 and then Subprogram_Access_Level
(Entity
(P
)) >
10113 Type_Access_Level
(Btyp
)
10116 ("subprogram must not be deeper than access type", P
);
10118 -- Check the restriction of 3.10.2(32) that disallows the
10119 -- access attribute within a generic body when the ultimate
10120 -- ancestor of the type of the attribute is declared outside
10121 -- of the generic unit and the subprogram is declared within
10122 -- that generic unit. This includes any such attribute that
10123 -- occurs within the body of a generic unit that is a child
10124 -- of the generic unit where the subprogram is declared.
10126 -- The rule also prohibits applying the attribute when the
10127 -- access type is a generic formal access type (since the
10128 -- level of the actual type is not known). This restriction
10129 -- does not apply when the attribute type is an anonymous
10130 -- access-to-subprogram type. Note that this check was
10131 -- revised by AI-229, because the original Ada 95 rule
10132 -- was too lax. The original rule only applied when the
10133 -- subprogram was declared within the body of the generic,
10134 -- which allowed the possibility of dangling references).
10135 -- The rule was also too strict in some cases, in that it
10136 -- didn't permit the access to be declared in the generic
10137 -- spec, whereas the revised rule does (as long as it's not
10140 -- There are a couple of subtleties of the test for applying
10141 -- the check that are worth noting. First, we only apply it
10142 -- when the levels of the subprogram and access type are the
10143 -- same (the case where the subprogram is statically deeper
10144 -- was applied above, and the case where the type is deeper
10145 -- is always safe). Second, we want the check to apply
10146 -- within nested generic bodies and generic child unit
10147 -- bodies, but not to apply to an attribute that appears in
10148 -- the generic unit's specification. This is done by testing
10149 -- that the attribute's innermost enclosing generic body is
10150 -- not the same as the innermost generic body enclosing the
10151 -- generic unit where the subprogram is declared (we don't
10152 -- want the check to apply when the access attribute is in
10153 -- the spec and there's some other generic body enclosing
10154 -- generic). Finally, there's no point applying the check
10155 -- when within an instance, because any violations will have
10156 -- been caught by the compilation of the generic unit.
10158 -- We relax this check in Relaxed_RM_Semantics mode for
10159 -- compatibility with legacy code for use by Ada source
10160 -- code analyzers (e.g. CodePeer).
10162 elsif Attr_Id
= Attribute_Access
10163 and then not Relaxed_RM_Semantics
10164 and then not In_Instance
10165 and then Present
(Enclosing_Generic_Unit
(Entity
(P
)))
10166 and then Present
(Enclosing_Generic_Body
(N
))
10167 and then Enclosing_Generic_Body
(N
) /=
10168 Enclosing_Generic_Body
10169 (Enclosing_Generic_Unit
(Entity
(P
)))
10170 and then Subprogram_Access_Level
(Entity
(P
)) =
10171 Type_Access_Level
(Btyp
)
10172 and then Ekind
(Btyp
) /=
10173 E_Anonymous_Access_Subprogram_Type
10174 and then Ekind
(Btyp
) /=
10175 E_Anonymous_Access_Protected_Subprogram_Type
10177 -- The attribute type's ultimate ancestor must be
10178 -- declared within the same generic unit as the
10179 -- subprogram is declared (including within another
10180 -- nested generic unit). The error message is
10181 -- specialized to say "ancestor" for the case where the
10182 -- access type is not its own ancestor, since saying
10183 -- simply "access type" would be very confusing.
10185 if not Declared_Within_Generic_Unit
10187 Enclosing_Generic_Unit
(Entity
(P
)))
10190 ("''Access attribute not allowed in generic body",
10193 if Root_Type
(Btyp
) = Btyp
then
10196 "access type & is declared outside " &
10197 "generic unit (RM 3.10.2(32))", N
, Btyp
);
10200 ("\because ancestor of " &
10201 "access type & is declared outside " &
10202 "generic unit (RM 3.10.2(32))", N
, Btyp
);
10206 ("\move ''Access to private part, or " &
10207 "(Ada 2005) use anonymous access type instead of &",
10210 -- If the ultimate ancestor of the attribute's type is
10211 -- a formal type, then the attribute is illegal because
10212 -- the actual type might be declared at a higher level.
10213 -- The error message is specialized to say "ancestor"
10214 -- for the case where the access type is not its own
10215 -- ancestor, since saying simply "access type" would be
10218 elsif Is_Generic_Type
(Root_Type
(Btyp
)) then
10219 if Root_Type
(Btyp
) = Btyp
then
10221 ("access type must not be a generic formal type",
10225 ("ancestor access type must not be a generic " &
10232 -- If this is a renaming, an inherited operation, or a
10233 -- subprogram instance, use the original entity. This may make
10234 -- the node type-inconsistent, so this transformation can only
10235 -- be done if the node will not be reanalyzed. In particular,
10236 -- if it is within a default expression, the transformation
10237 -- must be delayed until the default subprogram is created for
10238 -- it, when the enclosing subprogram is frozen.
10240 if Is_Entity_Name
(P
)
10241 and then Is_Overloadable
(Entity
(P
))
10242 and then Present
(Alias
(Entity
(P
)))
10243 and then Expander_Active
10246 New_Occurrence_Of
(Alias
(Entity
(P
)), Sloc
(P
)));
10249 elsif Nkind
(P
) = N_Selected_Component
10250 and then Is_Overloadable
(Entity
(Selector_Name
(P
)))
10252 -- Protected operation. If operation is overloaded, must
10253 -- disambiguate. Prefix that denotes protected object itself
10254 -- is resolved with its own type.
10256 if Attr_Id
= Attribute_Unchecked_Access
then
10257 Error_Msg_Name_1
:= Aname
;
10259 ("attribute% cannot be applied to protected operation", P
);
10262 Resolve
(Prefix
(P
));
10263 Generate_Reference
(Entity
(Selector_Name
(P
)), P
);
10265 -- Implement check implied by 3.10.2 (18.1/2) : F.all'access is
10266 -- statically illegal if F is an anonymous access to subprogram.
10268 elsif Nkind
(P
) = N_Explicit_Dereference
10269 and then Is_Entity_Name
(Prefix
(P
))
10270 and then Ekind
(Etype
(Entity
(Prefix
(P
)))) =
10271 E_Anonymous_Access_Subprogram_Type
10273 Error_Msg_N
("anonymous access to subprogram "
10274 & "has deeper accessibility than any master", P
);
10276 elsif Is_Overloaded
(P
) then
10278 -- Use the designated type of the context to disambiguate
10279 -- Note that this was not strictly conformant to Ada 95,
10280 -- but was the implementation adopted by most Ada 95 compilers.
10281 -- The use of the context type to resolve an Access attribute
10282 -- reference is now mandated in AI-235 for Ada 2005.
10285 Index
: Interp_Index
;
10289 Get_First_Interp
(P
, Index
, It
);
10290 while Present
(It
.Typ
) loop
10291 if Covers
(Designated_Type
(Typ
), It
.Typ
) then
10292 Resolve
(P
, It
.Typ
);
10296 Get_Next_Interp
(Index
, It
);
10303 -- X'Access is illegal if X denotes a constant and the access type
10304 -- is access-to-variable. Same for 'Unchecked_Access. The rule
10305 -- does not apply to 'Unrestricted_Access. If the reference is a
10306 -- default-initialized aggregate component for a self-referential
10307 -- type the reference is legal.
10309 if not (Ekind
(Btyp
) = E_Access_Subprogram_Type
10310 or else Ekind
(Btyp
) = E_Anonymous_Access_Subprogram_Type
10311 or else (Is_Record_Type
(Btyp
)
10313 Present
(Corresponding_Remote_Type
(Btyp
)))
10314 or else Ekind
(Btyp
) = E_Access_Protected_Subprogram_Type
10315 or else Ekind
(Btyp
)
10316 = E_Anonymous_Access_Protected_Subprogram_Type
10317 or else Is_Access_Constant
(Btyp
)
10318 or else Is_Variable
(P
)
10319 or else Attr_Id
= Attribute_Unrestricted_Access
)
10321 if Is_Entity_Name
(P
)
10322 and then Is_Type
(Entity
(P
))
10324 -- Legality of a self-reference through an access
10325 -- attribute has been verified in Analyze_Access_Attribute.
10329 elsif Comes_From_Source
(N
) then
10330 Error_Msg_F
("access-to-variable designates constant", P
);
10334 Des_Btyp
:= Designated_Type
(Btyp
);
10336 if Ada_Version
>= Ada_2005
10337 and then Is_Incomplete_Type
(Des_Btyp
)
10339 -- Ada 2005 (AI-412): If the (sub)type is a limited view of an
10340 -- imported entity, and the non-limited view is visible, make
10341 -- use of it. If it is an incomplete subtype, use the base type
10344 if From_Limited_With
(Des_Btyp
)
10345 and then Present
(Non_Limited_View
(Des_Btyp
))
10347 Des_Btyp
:= Non_Limited_View
(Des_Btyp
);
10349 elsif Ekind
(Des_Btyp
) = E_Incomplete_Subtype
then
10350 Des_Btyp
:= Etype
(Des_Btyp
);
10354 if (Attr_Id
= Attribute_Access
10356 Attr_Id
= Attribute_Unchecked_Access
)
10357 and then (Ekind
(Btyp
) = E_General_Access_Type
10358 or else Ekind
(Btyp
) = E_Anonymous_Access_Type
)
10360 -- Ada 2005 (AI-230): Check the accessibility of anonymous
10361 -- access types for stand-alone objects, record and array
10362 -- components, and return objects. For a component definition
10363 -- the level is the same of the enclosing composite type.
10365 if Ada_Version
>= Ada_2005
10366 and then (Is_Local_Anonymous_Access
(Btyp
)
10368 -- Handle cases where Btyp is the anonymous access
10369 -- type of an Ada 2012 stand-alone object.
10371 or else Nkind
(Associated_Node_For_Itype
(Btyp
)) =
10372 N_Object_Declaration
)
10374 Object_Access_Level
(P
) > Deepest_Type_Access_Level
(Btyp
)
10375 and then Attr_Id
= Attribute_Access
10377 -- In an instance, this is a runtime check, but one we know
10378 -- will fail, so generate an appropriate warning. As usual,
10379 -- this kind of warning is an error in SPARK mode.
10381 if In_Instance_Body
then
10382 Error_Msg_Warn
:= SPARK_Mode
/= On
;
10384 ("non-local pointer cannot point to local object<<", P
);
10385 Error_Msg_F
("\Program_Error [<<", P
);
10388 Make_Raise_Program_Error
(Loc
,
10389 Reason
=> PE_Accessibility_Check_Failed
));
10390 Set_Etype
(N
, Typ
);
10394 ("non-local pointer cannot point to local object", P
);
10398 if Is_Dependent_Component_Of_Mutable_Object
(P
) then
10400 ("illegal attribute for discriminant-dependent component",
10404 -- Check static matching rule of 3.10.2(27). Nominal subtype
10405 -- of the prefix must statically match the designated type.
10407 Nom_Subt
:= Etype
(P
);
10409 if Is_Constr_Subt_For_U_Nominal
(Nom_Subt
) then
10410 Nom_Subt
:= Base_Type
(Nom_Subt
);
10413 if Is_Tagged_Type
(Designated_Type
(Typ
)) then
10415 -- If the attribute is in the context of an access
10416 -- parameter, then the prefix is allowed to be of
10417 -- the class-wide type (by AI-127).
10419 if Ekind
(Typ
) = E_Anonymous_Access_Type
then
10420 if not Covers
(Designated_Type
(Typ
), Nom_Subt
)
10421 and then not Covers
(Nom_Subt
, Designated_Type
(Typ
))
10427 Desig
:= Designated_Type
(Typ
);
10429 if Is_Class_Wide_Type
(Desig
) then
10430 Desig
:= Etype
(Desig
);
10433 if Is_Anonymous_Tagged_Base
(Nom_Subt
, Desig
) then
10438 ("type of prefix: & not compatible",
10441 ("\with &, the expected designated type",
10442 P
, Designated_Type
(Typ
));
10447 elsif not Covers
(Designated_Type
(Typ
), Nom_Subt
)
10449 (not Is_Class_Wide_Type
(Designated_Type
(Typ
))
10450 and then Is_Class_Wide_Type
(Nom_Subt
))
10453 ("type of prefix: & is not covered", P
, Nom_Subt
);
10455 ("\by &, the expected designated type" &
10456 " (RM 3.10.2 (27))", P
, Designated_Type
(Typ
));
10459 if Is_Class_Wide_Type
(Designated_Type
(Typ
))
10460 and then Has_Discriminants
(Etype
(Designated_Type
(Typ
)))
10461 and then Is_Constrained
(Etype
(Designated_Type
(Typ
)))
10462 and then Designated_Type
(Typ
) /= Nom_Subt
10464 Apply_Discriminant_Check
10465 (N
, Etype
(Designated_Type
(Typ
)));
10468 -- Ada 2005 (AI-363): Require static matching when designated
10469 -- type has discriminants and a constrained partial view, since
10470 -- in general objects of such types are mutable, so we can't
10471 -- allow the access value to designate a constrained object
10472 -- (because access values must be assumed to designate mutable
10473 -- objects when designated type does not impose a constraint).
10475 elsif Subtypes_Statically_Match
(Des_Btyp
, Nom_Subt
) then
10478 elsif Has_Discriminants
(Designated_Type
(Typ
))
10479 and then not Is_Constrained
(Des_Btyp
)
10481 (Ada_Version
< Ada_2005
10483 not Object_Type_Has_Constrained_Partial_View
10484 (Typ
=> Designated_Type
(Base_Type
(Typ
)),
10485 Scop
=> Current_Scope
))
10491 ("object subtype must statically match "
10492 & "designated subtype", P
);
10494 if Is_Entity_Name
(P
)
10495 and then Is_Array_Type
(Designated_Type
(Typ
))
10498 D
: constant Node_Id
:= Declaration_Node
(Entity
(P
));
10501 ("aliased object has explicit bounds??", D
);
10503 ("\declare without bounds (and with explicit "
10504 & "initialization)??", D
);
10506 ("\for use with unconstrained access??", D
);
10511 -- Check the static accessibility rule of 3.10.2(28). Note that
10512 -- this check is not performed for the case of an anonymous
10513 -- access type, since the access attribute is always legal
10514 -- in such a context.
10516 if Attr_Id
/= Attribute_Unchecked_Access
10517 and then Ekind
(Btyp
) = E_General_Access_Type
10519 Object_Access_Level
(P
) > Deepest_Type_Access_Level
(Btyp
)
10521 Accessibility_Message
;
10526 if Ekind_In
(Btyp
, E_Access_Protected_Subprogram_Type
,
10527 E_Anonymous_Access_Protected_Subprogram_Type
)
10529 if Is_Entity_Name
(P
)
10530 and then not Is_Protected_Type
(Scope
(Entity
(P
)))
10532 Error_Msg_F
("context requires a protected subprogram", P
);
10534 -- Check accessibility of protected object against that of the
10535 -- access type, but only on user code, because the expander
10536 -- creates access references for handlers. If the context is an
10537 -- anonymous_access_to_protected, there are no accessibility
10538 -- checks either. Omit check entirely for Unrestricted_Access.
10540 elsif Object_Access_Level
(P
) > Deepest_Type_Access_Level
(Btyp
)
10541 and then Comes_From_Source
(N
)
10542 and then Ekind
(Btyp
) = E_Access_Protected_Subprogram_Type
10543 and then Attr_Id
/= Attribute_Unrestricted_Access
10545 Accessibility_Message
;
10548 -- AI05-0225: If the context is not an access to protected
10549 -- function, the prefix must be a variable, given that it may
10550 -- be used subsequently in a protected call.
10552 elsif Nkind
(P
) = N_Selected_Component
10553 and then not Is_Variable
(Prefix
(P
))
10554 and then Ekind
(Entity
(Selector_Name
(P
))) /= E_Function
10557 ("target object of access to protected procedure "
10558 & "must be variable", N
);
10560 elsif Is_Entity_Name
(P
) then
10561 Check_Internal_Protected_Use
(N
, Entity
(P
));
10564 elsif Ekind_In
(Btyp
, E_Access_Subprogram_Type
,
10565 E_Anonymous_Access_Subprogram_Type
)
10566 and then Ekind
(Etype
(N
)) = E_Access_Protected_Subprogram_Type
10568 Error_Msg_F
("context requires a non-protected subprogram", P
);
10571 -- The context cannot be a pool-specific type, but this is a
10572 -- legality rule, not a resolution rule, so it must be checked
10573 -- separately, after possibly disambiguation (see AI-245).
10575 if Ekind
(Btyp
) = E_Access_Type
10576 and then Attr_Id
/= Attribute_Unrestricted_Access
10578 Wrong_Type
(N
, Typ
);
10581 -- The context may be a constrained access type (however ill-
10582 -- advised such subtypes might be) so in order to generate a
10583 -- constraint check when needed set the type of the attribute
10584 -- reference to the base type of the context.
10586 Set_Etype
(N
, Btyp
);
10588 -- Check for incorrect atomic/volatile reference (RM C.6(12))
10590 if Attr_Id
/= Attribute_Unrestricted_Access
then
10591 if Is_Atomic_Object
(P
)
10592 and then not Is_Atomic
(Designated_Type
(Typ
))
10595 ("access to atomic object cannot yield access-to-" &
10596 "non-atomic type", P
);
10598 elsif Is_Volatile_Object
(P
)
10599 and then not Is_Volatile
(Designated_Type
(Typ
))
10602 ("access to volatile object cannot yield access-to-" &
10603 "non-volatile type", P
);
10607 -- Check for unrestricted access where expected type is a thin
10608 -- pointer to an unconstrained array.
10610 if Non_Aliased_Prefix
(N
)
10611 and then Has_Size_Clause
(Typ
)
10612 and then RM_Size
(Typ
) = System_Address_Size
10615 DT
: constant Entity_Id
:= Designated_Type
(Typ
);
10617 if Is_Array_Type
(DT
) and then not Is_Constrained
(DT
) then
10619 ("illegal use of Unrestricted_Access attribute", P
);
10621 ("\attempt to generate thin pointer to unaliased "
10627 -- Mark that address of entity is taken
10629 if Is_Entity_Name
(P
) then
10630 Set_Address_Taken
(Entity
(P
));
10633 -- Deal with possible elaboration check
10635 if Is_Entity_Name
(P
) and then Is_Subprogram
(Entity
(P
)) then
10637 Subp_Id
: constant Entity_Id
:= Entity
(P
);
10638 Scop
: constant Entity_Id
:= Scope
(Subp_Id
);
10639 Subp_Decl
: constant Node_Id
:=
10640 Unit_Declaration_Node
(Subp_Id
);
10641 Flag_Id
: Entity_Id
;
10642 Subp_Body
: Node_Id
;
10644 -- If the access has been taken and the body of the subprogram
10645 -- has not been see yet, indirect calls must be protected with
10646 -- elaboration checks. We have the proper elaboration machinery
10647 -- for subprograms declared in packages, but within a block or
10648 -- a subprogram the body will appear in the same declarative
10649 -- part, and we must insert a check in the eventual body itself
10650 -- using the elaboration flag that we generate now. The check
10651 -- is then inserted when the body is expanded. This processing
10652 -- is not needed for a stand alone expression function because
10653 -- the internally generated spec and body are always inserted
10654 -- as a pair in the same declarative list.
10658 and then Comes_From_Source
(Subp_Id
)
10659 and then Comes_From_Source
(N
)
10660 and then In_Open_Scopes
(Scop
)
10661 and then Ekind_In
(Scop
, E_Block
, E_Procedure
, E_Function
)
10662 and then not Has_Completion
(Subp_Id
)
10663 and then No
(Elaboration_Entity
(Subp_Id
))
10664 and then Nkind
(Subp_Decl
) = N_Subprogram_Declaration
10665 and then Nkind
(Original_Node
(Subp_Decl
)) /=
10666 N_Expression_Function
10668 -- Create elaboration variable for it
10670 Flag_Id
:= Make_Temporary
(Loc
, 'E');
10671 Set_Elaboration_Entity
(Subp_Id
, Flag_Id
);
10672 Set_Is_Frozen
(Flag_Id
);
10674 -- Insert declaration for flag after subprogram
10675 -- declaration. Note that attribute reference may
10676 -- appear within a nested scope.
10678 Insert_After_And_Analyze
(Subp_Decl
,
10679 Make_Object_Declaration
(Loc
,
10680 Defining_Identifier
=> Flag_Id
,
10681 Object_Definition
=>
10682 New_Occurrence_Of
(Standard_Short_Integer
, Loc
),
10684 Make_Integer_Literal
(Loc
, Uint_0
)));
10687 -- Taking the 'Access of an expression function freezes its
10688 -- expression (RM 13.14 10.3/3). This does not apply to an
10689 -- expression function that acts as a completion because the
10690 -- generated body is immediately analyzed and the expression
10691 -- is automatically frozen.
10693 if Is_Expression_Function
(Subp_Id
)
10694 and then Present
(Corresponding_Body
(Subp_Decl
))
10697 Unit_Declaration_Node
(Corresponding_Body
(Subp_Decl
));
10699 -- The body has already been analyzed when the expression
10700 -- function acts as a completion.
10702 if Analyzed
(Subp_Body
) then
10705 -- Attribute 'Access may appear within the generated body
10706 -- of the expression function subject to the attribute:
10708 -- function F is (... F'Access ...);
10710 -- If the expression function is on the scope stack, then
10711 -- the body is currently being analyzed. Do not reanalyze
10712 -- it because this will lead to infinite recursion.
10714 elsif In_Open_Scopes
(Subp_Id
) then
10717 -- Analyze the body of the expression function to freeze
10718 -- the expression. This takes care of the case where the
10719 -- 'Access is part of dispatch table initialization and
10720 -- the generated body of the expression function has not
10721 -- been analyzed yet.
10724 Analyze
(Subp_Body
);
10729 end Access_Attribute
;
10735 -- Deal with resolving the type for Address attribute, overloading
10736 -- is not permitted here, since there is no context to resolve it.
10738 when Attribute_Address | Attribute_Code_Address
=>
10739 Address_Attribute
: begin
10741 -- To be safe, assume that if the address of a variable is taken,
10742 -- it may be modified via this address, so note modification.
10744 if Is_Variable
(P
) then
10745 Note_Possible_Modification
(P
, Sure
=> False);
10748 if Nkind
(P
) in N_Subexpr
10749 and then Is_Overloaded
(P
)
10751 Get_First_Interp
(P
, Index
, It
);
10752 Get_Next_Interp
(Index
, It
);
10754 if Present
(It
.Nam
) then
10755 Error_Msg_Name_1
:= Aname
;
10757 ("prefix of % attribute cannot be overloaded", P
);
10761 if not Is_Entity_Name
(P
)
10762 or else not Is_Overloadable
(Entity
(P
))
10764 if not Is_Task_Type
(Etype
(P
))
10765 or else Nkind
(P
) = N_Explicit_Dereference
10771 -- If this is the name of a derived subprogram, or that of a
10772 -- generic actual, the address is that of the original entity.
10774 if Is_Entity_Name
(P
)
10775 and then Is_Overloadable
(Entity
(P
))
10776 and then Present
(Alias
(Entity
(P
)))
10779 New_Occurrence_Of
(Alias
(Entity
(P
)), Sloc
(P
)));
10782 if Is_Entity_Name
(P
) then
10783 Set_Address_Taken
(Entity
(P
));
10786 if Nkind
(P
) = N_Slice
then
10788 -- Arr (X .. Y)'address is identical to Arr (X)'address,
10789 -- even if the array is packed and the slice itself is not
10790 -- addressable. Transform the prefix into an indexed component.
10792 -- Note that the transformation is safe only if we know that
10793 -- the slice is non-null. That is because a null slice can have
10794 -- an out of bounds index value.
10796 -- Right now, gigi blows up if given 'Address on a slice as a
10797 -- result of some incorrect freeze nodes generated by the front
10798 -- end, and this covers up that bug in one case, but the bug is
10799 -- likely still there in the cases not handled by this code ???
10801 -- It's not clear what 'Address *should* return for a null
10802 -- slice with out of bounds indexes, this might be worth an ARG
10805 -- One approach would be to do a length check unconditionally,
10806 -- and then do the transformation below unconditionally, but
10807 -- analyze with checks off, avoiding the problem of the out of
10808 -- bounds index. This approach would interpret the address of
10809 -- an out of bounds null slice as being the address where the
10810 -- array element would be if there was one, which is probably
10811 -- as reasonable an interpretation as any ???
10814 Loc
: constant Source_Ptr
:= Sloc
(P
);
10815 D
: constant Node_Id
:= Discrete_Range
(P
);
10819 if Is_Entity_Name
(D
)
10822 (Type_Low_Bound
(Entity
(D
)),
10823 Type_High_Bound
(Entity
(D
)))
10826 Make_Attribute_Reference
(Loc
,
10827 Prefix
=> (New_Occurrence_Of
(Entity
(D
), Loc
)),
10828 Attribute_Name
=> Name_First
);
10830 elsif Nkind
(D
) = N_Range
10831 and then Not_Null_Range
(Low_Bound
(D
), High_Bound
(D
))
10833 Lo
:= Low_Bound
(D
);
10839 if Present
(Lo
) then
10841 Make_Indexed_Component
(Loc
,
10842 Prefix
=> Relocate_Node
(Prefix
(P
)),
10843 Expressions
=> New_List
(Lo
)));
10845 Analyze_And_Resolve
(P
);
10849 end Address_Attribute
;
10855 -- Prefix of Body_Version attribute can be a subprogram name which
10856 -- must not be resolved, since this is not a call.
10858 when Attribute_Body_Version
=>
10865 -- Prefix of Caller attribute is an entry name which must not
10866 -- be resolved, since this is definitely not an entry call.
10868 when Attribute_Caller
=>
10875 -- Shares processing with Address attribute
10881 -- If the prefix of the Count attribute is an entry name it must not
10882 -- be resolved, since this is definitely not an entry call. However,
10883 -- if it is an element of an entry family, the index itself may
10884 -- have to be resolved because it can be a general expression.
10886 when Attribute_Count
=>
10887 if Nkind
(P
) = N_Indexed_Component
10888 and then Is_Entity_Name
(Prefix
(P
))
10891 Indx
: constant Node_Id
:= First
(Expressions
(P
));
10892 Fam
: constant Entity_Id
:= Entity
(Prefix
(P
));
10894 Resolve
(Indx
, Entry_Index_Type
(Fam
));
10895 Apply_Range_Check
(Indx
, Entry_Index_Type
(Fam
));
10903 -- Prefix of the Elaborated attribute is a subprogram name which
10904 -- must not be resolved, since this is definitely not a call. Note
10905 -- that it is a library unit, so it cannot be overloaded here.
10907 when Attribute_Elaborated
=>
10914 -- Prefix of Enabled attribute is a check name, which must be treated
10915 -- specially and not touched by Resolve.
10917 when Attribute_Enabled
=>
10924 -- Do not resolve the prefix of Loop_Entry, instead wait until the
10925 -- attribute has been expanded (see Expand_Loop_Entry_Attributes).
10926 -- The delay ensures that any generated checks or temporaries are
10927 -- inserted before the relocated prefix.
10929 when Attribute_Loop_Entry
=>
10932 --------------------
10933 -- Mechanism_Code --
10934 --------------------
10936 -- Prefix of the Mechanism_Code attribute is a function name
10937 -- which must not be resolved. Should we check for overloaded ???
10939 when Attribute_Mechanism_Code
=>
10946 -- Most processing is done in sem_dist, after determining the
10947 -- context type. Node is rewritten as a conversion to a runtime call.
10949 when Attribute_Partition_ID
=>
10950 Process_Partition_Id
(N
);
10957 when Attribute_Pool_Address
=>
10964 -- We replace the Range attribute node with a range expression whose
10965 -- bounds are the 'First and 'Last attributes applied to the same
10966 -- prefix. The reason that we do this transformation here instead of
10967 -- in the expander is that it simplifies other parts of the semantic
10968 -- analysis which assume that the Range has been replaced; thus it
10969 -- must be done even when in semantic-only mode (note that the RM
10970 -- specifically mentions this equivalence, we take care that the
10971 -- prefix is only evaluated once).
10973 when Attribute_Range
=> Range_Attribute
:
10980 if not Is_Entity_Name
(P
)
10981 or else not Is_Type
(Entity
(P
))
10986 Dims
:= Expressions
(N
);
10989 Make_Attribute_Reference
(Loc
,
10990 Prefix
=> Duplicate_Subexpr
(P
, Name_Req
=> True),
10991 Attribute_Name
=> Name_Last
,
10992 Expressions
=> Dims
);
10995 Make_Attribute_Reference
(Loc
,
10997 Attribute_Name
=> Name_First
,
10998 Expressions
=> (Dims
));
11000 -- Do not share the dimension indicator, if present. Even
11001 -- though it is a static constant, its source location
11002 -- may be modified when printing expanded code and node
11003 -- sharing will lead to chaos in Sprint.
11005 if Present
(Dims
) then
11006 Set_Expressions
(LB
,
11007 New_List
(New_Copy_Tree
(First
(Dims
))));
11010 -- If the original was marked as Must_Not_Freeze (see code
11011 -- in Sem_Ch3.Make_Index), then make sure the rewriting
11012 -- does not freeze either.
11014 if Must_Not_Freeze
(N
) then
11015 Set_Must_Not_Freeze
(HB
);
11016 Set_Must_Not_Freeze
(LB
);
11017 Set_Must_Not_Freeze
(Prefix
(HB
));
11018 Set_Must_Not_Freeze
(Prefix
(LB
));
11021 if Raises_Constraint_Error
(Prefix
(N
)) then
11023 -- Preserve Sloc of prefix in the new bounds, so that
11024 -- the posted warning can be removed if we are within
11025 -- unreachable code.
11027 Set_Sloc
(LB
, Sloc
(Prefix
(N
)));
11028 Set_Sloc
(HB
, Sloc
(Prefix
(N
)));
11031 Rewrite
(N
, Make_Range
(Loc
, LB
, HB
));
11032 Analyze_And_Resolve
(N
, Typ
);
11034 -- Ensure that the expanded range does not have side effects
11036 Force_Evaluation
(LB
);
11037 Force_Evaluation
(HB
);
11039 -- Normally after resolving attribute nodes, Eval_Attribute
11040 -- is called to do any possible static evaluation of the node.
11041 -- However, here since the Range attribute has just been
11042 -- transformed into a range expression it is no longer an
11043 -- attribute node and therefore the call needs to be avoided
11044 -- and is accomplished by simply returning from the procedure.
11047 end Range_Attribute
;
11053 -- We will only come here during the prescan of a spec expression
11054 -- containing a Result attribute. In that case the proper Etype has
11055 -- already been set, and nothing more needs to be done here.
11057 when Attribute_Result
=>
11064 -- Prefix must not be resolved in this case, since it is not a
11065 -- real entity reference. No action of any kind is require.
11067 when Attribute_UET_Address
=>
11070 ----------------------
11071 -- Unchecked_Access --
11072 ----------------------
11074 -- Processing is shared with Access
11076 -------------------------
11077 -- Unrestricted_Access --
11078 -------------------------
11080 -- Processing is shared with Access
11086 -- Resolve aggregate components in component associations
11088 when Attribute_Update
=>
11090 Aggr
: constant Node_Id
:= First
(Expressions
(N
));
11091 Typ
: constant Entity_Id
:= Etype
(Prefix
(N
));
11097 -- Set the Etype of the aggregate to that of the prefix, even
11098 -- though the aggregate may not be a proper representation of a
11099 -- value of the type (missing or duplicated associations, etc.)
11100 -- Complete resolution of the prefix. Note that in Ada 2012 it
11101 -- can be a qualified expression that is e.g. an aggregate.
11103 Set_Etype
(Aggr
, Typ
);
11104 Resolve
(Prefix
(N
), Typ
);
11106 -- For an array type, resolve expressions with the component
11107 -- type of the array, and apply constraint checks when needed.
11109 if Is_Array_Type
(Typ
) then
11110 Assoc
:= First
(Component_Associations
(Aggr
));
11111 while Present
(Assoc
) loop
11112 Expr
:= Expression
(Assoc
);
11113 Resolve
(Expr
, Component_Type
(Typ
));
11115 -- For scalar array components set Do_Range_Check when
11116 -- needed. Constraint checking on non-scalar components
11117 -- is done in Aggregate_Constraint_Checks, but only if
11118 -- full analysis is enabled. These flags are not set in
11119 -- the front-end in GnatProve mode.
11121 if Is_Scalar_Type
(Component_Type
(Typ
))
11122 and then not Is_OK_Static_Expression
(Expr
)
11124 if Is_Entity_Name
(Expr
)
11125 and then Etype
(Expr
) = Component_Type
(Typ
)
11130 Set_Do_Range_Check
(Expr
);
11134 -- The choices in the association are static constants,
11135 -- or static aggregates each of whose components belongs
11136 -- to the proper index type. However, they must also
11137 -- belong to the index subtype (s) of the prefix, which
11138 -- may be a subtype (e.g. given by a slice).
11140 -- Choices may also be identifiers with no staticness
11141 -- requirements, in which case they must resolve to the
11150 C
:= First
(Choices
(Assoc
));
11151 while Present
(C
) loop
11152 Indx
:= First_Index
(Etype
(Prefix
(N
)));
11154 if Nkind
(C
) /= N_Aggregate
then
11155 Analyze_And_Resolve
(C
, Etype
(Indx
));
11156 Apply_Constraint_Check
(C
, Etype
(Indx
));
11157 Check_Non_Static_Context
(C
);
11160 C_E
:= First
(Expressions
(C
));
11161 while Present
(C_E
) loop
11162 Analyze_And_Resolve
(C_E
, Etype
(Indx
));
11163 Apply_Constraint_Check
(C_E
, Etype
(Indx
));
11164 Check_Non_Static_Context
(C_E
);
11178 -- For a record type, use type of each component, which is
11179 -- recorded during analysis.
11182 Assoc
:= First
(Component_Associations
(Aggr
));
11183 while Present
(Assoc
) loop
11184 Comp
:= First
(Choices
(Assoc
));
11185 Expr
:= Expression
(Assoc
);
11187 if Nkind
(Comp
) /= N_Others_Choice
11188 and then not Error_Posted
(Comp
)
11190 Resolve
(Expr
, Etype
(Entity
(Comp
)));
11192 if Is_Scalar_Type
(Etype
(Entity
(Comp
)))
11193 and then not Is_OK_Static_Expression
(Expr
)
11195 Set_Do_Range_Check
(Expr
);
11208 -- Apply range check. Note that we did not do this during the
11209 -- analysis phase, since we wanted Eval_Attribute to have a
11210 -- chance at finding an illegal out of range value.
11212 when Attribute_Val
=>
11214 -- Note that we do our own Eval_Attribute call here rather than
11215 -- use the common one, because we need to do processing after
11216 -- the call, as per above comment.
11218 Eval_Attribute
(N
);
11220 -- Eval_Attribute may replace the node with a raise CE, or
11221 -- fold it to a constant. Obviously we only apply a scalar
11222 -- range check if this did not happen.
11224 if Nkind
(N
) = N_Attribute_Reference
11225 and then Attribute_Name
(N
) = Name_Val
11227 Apply_Scalar_Range_Check
(First
(Expressions
(N
)), Btyp
);
11236 -- Prefix of Version attribute can be a subprogram name which
11237 -- must not be resolved, since this is not a call.
11239 when Attribute_Version
=>
11242 ----------------------
11243 -- Other Attributes --
11244 ----------------------
11246 -- For other attributes, resolve prefix unless it is a type. If
11247 -- the attribute reference itself is a type name ('Base and 'Class)
11248 -- then this is only legal within a task or protected record.
11251 if not Is_Entity_Name
(P
) or else not Is_Type
(Entity
(P
)) then
11255 -- If the attribute reference itself is a type name ('Base,
11256 -- 'Class) then this is only legal within a task or protected
11257 -- record. What is this all about ???
11259 if Is_Entity_Name
(N
) and then Is_Type
(Entity
(N
)) then
11260 if Is_Concurrent_Type
(Entity
(N
))
11261 and then In_Open_Scopes
(Entity
(P
))
11266 ("invalid use of subtype name in expression or call", N
);
11270 -- For attributes whose argument may be a string, complete
11271 -- resolution of argument now. This avoids premature expansion
11272 -- (and the creation of transient scopes) before the attribute
11273 -- reference is resolved.
11276 when Attribute_Value
=>
11277 Resolve
(First
(Expressions
(N
)), Standard_String
);
11279 when Attribute_Wide_Value
=>
11280 Resolve
(First
(Expressions
(N
)), Standard_Wide_String
);
11282 when Attribute_Wide_Wide_Value
=>
11283 Resolve
(First
(Expressions
(N
)), Standard_Wide_Wide_String
);
11285 when others => null;
11288 -- If the prefix of the attribute is a class-wide type then it
11289 -- will be expanded into a dispatching call to a predefined
11290 -- primitive. Therefore we must check for potential violation
11291 -- of such restriction.
11293 if Is_Class_Wide_Type
(Etype
(P
)) then
11294 Check_Restriction
(No_Dispatching_Calls
, N
);
11298 -- Normally the Freezing is done by Resolve but sometimes the Prefix
11299 -- is not resolved, in which case the freezing must be done now.
11301 -- For an elaboration check on a subprogram, we do not freeze its type.
11302 -- It may be declared in an unrelated scope, in particular in the case
11303 -- of a generic function whose type may remain unelaborated.
11305 if Attr_Id
= Attribute_Elaborated
then
11309 Freeze_Expression
(P
);
11312 -- Finally perform static evaluation on the attribute reference
11314 Analyze_Dimension
(N
);
11315 Eval_Attribute
(N
);
11316 end Resolve_Attribute
;
11318 ------------------------
11319 -- Set_Boolean_Result --
11320 ------------------------
11322 procedure Set_Boolean_Result
(N
: Node_Id
; B
: Boolean) is
11323 Loc
: constant Source_Ptr
:= Sloc
(N
);
11326 Rewrite
(N
, New_Occurrence_Of
(Standard_True
, Loc
));
11328 Rewrite
(N
, New_Occurrence_Of
(Standard_False
, Loc
));
11330 end Set_Boolean_Result
;
11332 --------------------------------
11333 -- Stream_Attribute_Available --
11334 --------------------------------
11336 function Stream_Attribute_Available
11338 Nam
: TSS_Name_Type
;
11339 Partial_View
: Node_Id
:= Empty
) return Boolean
11341 Etyp
: Entity_Id
:= Typ
;
11343 -- Start of processing for Stream_Attribute_Available
11346 -- We need some comments in this body ???
11348 if Has_Stream_Attribute_Definition
(Typ
, Nam
) then
11352 if Is_Class_Wide_Type
(Typ
) then
11353 return not Is_Limited_Type
(Typ
)
11354 or else Stream_Attribute_Available
(Etype
(Typ
), Nam
);
11357 if Nam
= TSS_Stream_Input
11358 and then Is_Abstract_Type
(Typ
)
11359 and then not Is_Class_Wide_Type
(Typ
)
11364 if not (Is_Limited_Type
(Typ
)
11365 or else (Present
(Partial_View
)
11366 and then Is_Limited_Type
(Partial_View
)))
11371 -- In Ada 2005, Input can invoke Read, and Output can invoke Write
11373 if Nam
= TSS_Stream_Input
11374 and then Ada_Version
>= Ada_2005
11375 and then Stream_Attribute_Available
(Etyp
, TSS_Stream_Read
)
11379 elsif Nam
= TSS_Stream_Output
11380 and then Ada_Version
>= Ada_2005
11381 and then Stream_Attribute_Available
(Etyp
, TSS_Stream_Write
)
11386 -- Case of Read and Write: check for attribute definition clause that
11387 -- applies to an ancestor type.
11389 while Etype
(Etyp
) /= Etyp
loop
11390 Etyp
:= Etype
(Etyp
);
11392 if Has_Stream_Attribute_Definition
(Etyp
, Nam
) then
11397 if Ada_Version
< Ada_2005
then
11399 -- In Ada 95 mode, also consider a non-visible definition
11402 Btyp
: constant Entity_Id
:= Implementation_Base_Type
(Typ
);
11405 and then Stream_Attribute_Available
11406 (Btyp
, Nam
, Partial_View
=> Typ
);
11411 end Stream_Attribute_Available
;