1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2016, 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 with System
.CRC32
; use System
.CRC32
;
83 package body Sem_Attr
is
85 True_Value
: constant Uint
:= Uint_1
;
86 False_Value
: constant Uint
:= Uint_0
;
87 -- Synonyms to be used when these constants are used as Boolean values
89 Bad_Attribute
: exception;
90 -- Exception raised if an error is detected during attribute processing,
91 -- used so that we can abandon the processing so we don't run into
92 -- trouble with cascaded errors.
94 -- The following array is the list of attributes defined in the Ada 83 RM.
95 -- In Ada 83 mode, these are the only recognized attributes. In other Ada
96 -- modes all these attributes are recognized, even if removed in Ada 95.
98 Attribute_83
: constant Attribute_Class_Array
:= Attribute_Class_Array
'(
101 Attribute_Alignment |
104 Attribute_Constrained |
111 Attribute_First_Bit |
117 Attribute_Leading_Part |
119 Attribute_Machine_Emax |
120 Attribute_Machine_Emin |
121 Attribute_Machine_Mantissa |
122 Attribute_Machine_Overflows |
123 Attribute_Machine_Radix |
124 Attribute_Machine_Rounds |
130 Attribute_Safe_Emax |
131 Attribute_Safe_Large |
132 Attribute_Safe_Small |
135 Attribute_Storage_Size |
137 Attribute_Terminated |
140 Attribute_Width => True,
143 -- The following array is the list of attributes defined in the Ada 2005
144 -- RM which are not defined in Ada 95. These are recognized in Ada 95 mode,
145 -- but in Ada 95 they are considered to be implementation defined.
147 Attribute_05 : constant Attribute_Class_Array := Attribute_Class_Array'(
148 Attribute_Machine_Rounding |
151 Attribute_Stream_Size |
152 Attribute_Wide_Wide_Width
=> True,
155 -- The following array is the list of attributes defined in the Ada 2012
156 -- RM which are not defined in Ada 2005. These are recognized in Ada 95
157 -- and Ada 2005 modes, but are considered to be implementation defined.
159 Attribute_12
: constant Attribute_Class_Array
:= Attribute_Class_Array
'(
160 Attribute_First_Valid |
161 Attribute_Has_Same_Storage |
162 Attribute_Last_Valid |
163 Attribute_Max_Alignment_For_Allocation => True,
166 -- The following array contains all attributes that imply a modification
167 -- of their prefixes or result in an access value. Such prefixes can be
168 -- considered as lvalues.
170 Attribute_Name_Implies_Lvalue_Prefix : constant Attribute_Class_Array :=
171 Attribute_Class_Array'(
176 Attribute_Unchecked_Access |
177 Attribute_Unrestricted_Access
=> True,
180 -----------------------
181 -- Local_Subprograms --
182 -----------------------
184 procedure Eval_Attribute
(N
: Node_Id
);
185 -- Performs compile time evaluation of attributes where possible, leaving
186 -- the Is_Static_Expression/Raises_Constraint_Error flags appropriately
187 -- set, and replacing the node with a literal node if the value can be
188 -- computed at compile time. All static attribute references are folded,
189 -- as well as a number of cases of non-static attributes that can always
190 -- be computed at compile time (e.g. floating-point model attributes that
191 -- are applied to non-static subtypes). Of course in such cases, the
192 -- Is_Static_Expression flag will not be set on the resulting literal.
193 -- Note that the only required action of this procedure is to catch the
194 -- static expression cases as described in the RM. Folding of other cases
195 -- is done where convenient, but some additional non-static folding is in
196 -- Expand_N_Attribute_Reference in cases where this is more convenient.
198 function Is_Anonymous_Tagged_Base
200 Typ
: Entity_Id
) return Boolean;
201 -- For derived tagged types that constrain parent discriminants we build
202 -- an anonymous unconstrained base type. We need to recognize the relation
203 -- between the two when analyzing an access attribute for a constrained
204 -- component, before the full declaration for Typ has been analyzed, and
205 -- where therefore the prefix of the attribute does not match the enclosing
208 procedure Set_Boolean_Result
(N
: Node_Id
; B
: Boolean);
209 -- Rewrites node N with an occurrence of either Standard_False or
210 -- Standard_True, depending on the value of the parameter B. The
211 -- result is marked as a static expression.
213 -----------------------
214 -- Analyze_Attribute --
215 -----------------------
217 procedure Analyze_Attribute
(N
: Node_Id
) is
218 Loc
: constant Source_Ptr
:= Sloc
(N
);
219 Aname
: constant Name_Id
:= Attribute_Name
(N
);
220 P
: constant Node_Id
:= Prefix
(N
);
221 Exprs
: constant List_Id
:= Expressions
(N
);
222 Attr_Id
: constant Attribute_Id
:= Get_Attribute_Id
(Aname
);
227 -- Type of prefix after analysis
229 P_Base_Type
: Entity_Id
;
230 -- Base type of prefix after analysis
232 -----------------------
233 -- Local Subprograms --
234 -----------------------
236 procedure Address_Checks
;
237 -- Semantic checks for valid use of Address attribute. This was made
238 -- a separate routine with the idea of using it for unrestricted access
239 -- which seems like it should follow the same rules, but that turned
240 -- out to be impractical. So now this is only used for Address.
242 procedure Analyze_Access_Attribute
;
243 -- Used for Access, Unchecked_Access, Unrestricted_Access attributes.
244 -- Internally, Id distinguishes which of the three cases is involved.
246 procedure Analyze_Attribute_Old_Result
247 (Legal
: out Boolean;
248 Spec_Id
: out Entity_Id
);
249 -- Common processing for attributes 'Old and 'Result. The routine checks
250 -- that the attribute appears in a postcondition-like aspect or pragma
251 -- associated with a suitable subprogram or a body. Flag Legal is set
252 -- when the above criteria are met. Spec_Id denotes the entity of the
253 -- subprogram [body] or Empty if the attribute is illegal.
255 procedure Bad_Attribute_For_Predicate
;
256 -- Output error message for use of a predicate (First, Last, Range) not
257 -- allowed with a type that has predicates. If the type is a generic
258 -- actual, then the message is a warning, and we generate code to raise
259 -- program error with an appropriate reason. No error message is given
260 -- for internally generated uses of the attributes. This legality rule
261 -- only applies to scalar types.
263 procedure Check_Array_Or_Scalar_Type
;
264 -- Common procedure used by First, Last, Range attribute to check
265 -- that the prefix is a constrained array or scalar type, or a name
266 -- of an array object, and that an argument appears only if appropriate
267 -- (i.e. only in the array case).
269 procedure Check_Array_Type
;
270 -- Common semantic checks for all array attributes. Checks that the
271 -- prefix is a constrained array type or the name of an array object.
272 -- The error message for non-arrays is specialized appropriately.
274 procedure Check_Asm_Attribute
;
275 -- Common semantic checks for Asm_Input and Asm_Output attributes
277 procedure Check_Component
;
278 -- Common processing for Bit_Position, First_Bit, Last_Bit, and
279 -- Position. Checks prefix is an appropriate selected component.
281 procedure Check_Decimal_Fixed_Point_Type
;
282 -- Check that prefix of attribute N is a decimal fixed-point type
284 procedure Check_Dereference
;
285 -- If the prefix of attribute is an object of an access type, then
286 -- introduce an explicit dereference, and adjust P_Type accordingly.
288 procedure Check_Discrete_Type
;
289 -- Verify that prefix of attribute N is a discrete type
292 -- Check that no attribute arguments are present
294 procedure Check_Either_E0_Or_E1
;
295 -- Check that there are zero or one attribute arguments present
298 -- Check that exactly one attribute argument is present
301 -- Check that two attribute arguments are present
303 procedure Check_Enum_Image
;
304 -- If the prefix type of 'Image is an enumeration type, set all its
305 -- literals as referenced, since the image function could possibly end
306 -- up referencing any of the literals indirectly. Same for Enum_Val.
307 -- Set the flag only if the reference is in the main code unit. Same
308 -- restriction when resolving 'Value; otherwise an improperly set
309 -- reference when analyzing an inlined body will lose a proper
310 -- warning on a useless with_clause.
312 procedure Check_First_Last_Valid
;
313 -- Perform all checks for First_Valid and Last_Valid attributes
315 procedure Check_Fixed_Point_Type
;
316 -- Verify that prefix of attribute N is a fixed type
318 procedure Check_Fixed_Point_Type_0
;
319 -- Verify that prefix of attribute N is a fixed type and that
320 -- no attribute expressions are present
322 procedure Check_Floating_Point_Type
;
323 -- Verify that prefix of attribute N is a float type
325 procedure Check_Floating_Point_Type_0
;
326 -- Verify that prefix of attribute N is a float type and that
327 -- no attribute expressions are present
329 procedure Check_Floating_Point_Type_1
;
330 -- Verify that prefix of attribute N is a float type and that
331 -- exactly one attribute expression is present
333 procedure Check_Floating_Point_Type_2
;
334 -- Verify that prefix of attribute N is a float type and that
335 -- two attribute expressions are present
337 procedure Check_SPARK_05_Restriction_On_Attribute
;
338 -- Issue an error in formal mode because attribute N is allowed
340 procedure Check_Integer_Type
;
341 -- Verify that prefix of attribute N is an integer type
343 procedure Check_Modular_Integer_Type
;
344 -- Verify that prefix of attribute N is a modular integer type
346 procedure Check_Not_CPP_Type
;
347 -- Check that P (the prefix of the attribute) is not an CPP type
348 -- for which no Ada predefined primitive is available.
350 procedure Check_Not_Incomplete_Type
;
351 -- Check that P (the prefix of the attribute) is not an incomplete
352 -- type or a private type for which no full view has been given.
354 procedure Check_Object_Reference
(P
: Node_Id
);
355 -- Check that P is an object reference
357 procedure Check_PolyORB_Attribute
;
358 -- Validity checking for PolyORB/DSA attribute
360 procedure Check_Program_Unit
;
361 -- Verify that prefix of attribute N is a program unit
363 procedure Check_Real_Type
;
364 -- Verify that prefix of attribute N is fixed or float type
366 procedure Check_Scalar_Type
;
367 -- Verify that prefix of attribute N is a scalar type
369 procedure Check_Standard_Prefix
;
370 -- Verify that prefix of attribute N is package Standard. Also checks
371 -- that there are no arguments.
373 procedure Check_Stream_Attribute
(Nam
: TSS_Name_Type
);
374 -- Validity checking for stream attribute. Nam is the TSS name of the
375 -- corresponding possible defined attribute function (e.g. for the
376 -- Read attribute, Nam will be TSS_Stream_Read).
378 procedure Check_System_Prefix
;
379 -- Verify that prefix of attribute N is package System
381 procedure Check_Task_Prefix
;
382 -- Verify that prefix of attribute N is a task or task type
384 procedure Check_Type
;
385 -- Verify that the prefix of attribute N is a type
387 procedure Check_Unit_Name
(Nod
: Node_Id
);
388 -- Check that Nod is of the form of a library unit name, i.e that
389 -- it is an identifier, or a selected component whose prefix is
390 -- itself of the form of a library unit name. Note that this is
391 -- quite different from Check_Program_Unit, since it only checks
392 -- the syntactic form of the name, not the semantic identity. This
393 -- is because it is used with attributes (Elab_Body, Elab_Spec and
394 -- Elaborated) which can refer to non-visible unit.
396 procedure Error_Attr
(Msg
: String; Error_Node
: Node_Id
);
397 pragma No_Return
(Error_Attr
);
398 procedure Error_Attr
;
399 pragma No_Return
(Error_Attr
);
400 -- Posts error using Error_Msg_N at given node, sets type of attribute
401 -- node to Any_Type, and then raises Bad_Attribute to avoid any further
402 -- semantic processing. The message typically contains a % insertion
403 -- character which is replaced by the attribute name. The call with
404 -- no arguments is used when the caller has already generated the
405 -- required error messages.
407 procedure Error_Attr_P
(Msg
: String);
408 pragma No_Return
(Error_Attr
);
409 -- Like Error_Attr, but error is posted at the start of the prefix
411 procedure Legal_Formal_Attribute
;
412 -- Common processing for attributes Definite and Has_Discriminants.
413 -- Checks that prefix is generic indefinite formal type.
415 procedure Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
;
416 -- Common processing for attributes Max_Alignment_For_Allocation and
417 -- Max_Size_In_Storage_Elements.
420 -- Common processing for attributes Max and Min
422 procedure Standard_Attribute
(Val
: Int
);
423 -- Used to process attributes whose prefix is package Standard which
424 -- yield values of type Universal_Integer. The attribute reference
425 -- node is rewritten with an integer literal of the given value which
426 -- is marked as static.
428 procedure Uneval_Old_Msg
;
429 -- Called when Loop_Entry or Old is used in a potentially unevaluated
430 -- expression. Generates appropriate message or warning depending on
431 -- the setting of Opt.Uneval_Old (or flags in an N_Aspect_Specification
432 -- node in the aspect case).
434 procedure Unexpected_Argument
(En
: Node_Id
);
435 -- Signal unexpected attribute argument (En is the argument)
437 procedure Validate_Non_Static_Attribute_Function_Call
;
438 -- Called when processing an attribute that is a function call to a
439 -- non-static function, i.e. an attribute function that either takes
440 -- non-scalar arguments or returns a non-scalar result. Verifies that
441 -- such a call does not appear in a preelaborable context.
447 procedure Address_Checks
is
449 -- An Address attribute created by expansion is legal even when it
450 -- applies to other entity-denoting expressions.
452 if not Comes_From_Source
(N
) then
455 -- Address attribute on a protected object self reference is legal
457 elsif Is_Protected_Self_Reference
(P
) then
460 -- Address applied to an entity
462 elsif Is_Entity_Name
(P
) then
464 Ent
: constant Entity_Id
:= Entity
(P
);
467 if Is_Subprogram
(Ent
) then
468 Set_Address_Taken
(Ent
);
469 Kill_Current_Values
(Ent
);
471 -- An Address attribute is accepted when generated by the
472 -- compiler for dispatching operation, and an error is
473 -- issued once the subprogram is frozen (to avoid confusing
474 -- errors about implicit uses of Address in the dispatch
475 -- table initialization).
477 if Has_Pragma_Inline_Always
(Entity
(P
))
478 and then Comes_From_Source
(P
)
481 ("prefix of % attribute cannot be Inline_Always "
484 -- It is illegal to apply 'Address to an intrinsic
485 -- subprogram. This is now formalized in AI05-0095.
486 -- In an instance, an attempt to obtain 'Address of an
487 -- intrinsic subprogram (e.g the renaming of a predefined
488 -- operator that is an actual) raises Program_Error.
490 elsif Convention
(Ent
) = Convention_Intrinsic
then
493 Make_Raise_Program_Error
(Loc
,
494 Reason
=> PE_Address_Of_Intrinsic
));
497 Error_Msg_Name_1
:= Aname
;
499 ("cannot take % of intrinsic subprogram", N
);
502 -- Issue an error if prefix denotes an eliminated subprogram
505 Check_For_Eliminated_Subprogram
(P
, Ent
);
508 -- Object or label reference
510 elsif Is_Object
(Ent
) or else Ekind
(Ent
) = E_Label
then
511 Set_Address_Taken
(Ent
);
513 -- Deal with No_Implicit_Aliasing restriction
515 if Restriction_Check_Required
(No_Implicit_Aliasing
) then
516 if not Is_Aliased_View
(P
) then
517 Check_Restriction
(No_Implicit_Aliasing
, P
);
519 Check_No_Implicit_Aliasing
(P
);
523 -- If we have an address of an object, and the attribute
524 -- comes from source, then set the object as potentially
525 -- source modified. We do this because the resulting address
526 -- can potentially be used to modify the variable and we
527 -- might not detect this, leading to some junk warnings.
529 Set_Never_Set_In_Source
(Ent
, False);
531 -- Allow Address to be applied to task or protected type,
532 -- returning null address (what is that about???)
534 elsif (Is_Concurrent_Type
(Etype
(Ent
))
535 and then Etype
(Ent
) = Base_Type
(Ent
))
536 or else Ekind
(Ent
) = E_Package
537 or else Is_Generic_Unit
(Ent
)
540 New_Occurrence_Of
(RTE
(RE_Null_Address
), Sloc
(N
)));
542 -- Anything else is illegal
545 Error_Attr
("invalid prefix for % attribute", P
);
551 elsif Is_Object_Reference
(P
) then
554 -- Subprogram called using dot notation
556 elsif Nkind
(P
) = N_Selected_Component
557 and then Is_Subprogram
(Entity
(Selector_Name
(P
)))
561 -- What exactly are we allowing here ??? and is this properly
562 -- documented in the sinfo documentation for this node ???
564 elsif Relaxed_RM_Semantics
565 and then Nkind
(P
) = N_Attribute_Reference
569 -- All other non-entity name cases are illegal
572 Error_Attr
("invalid prefix for % attribute", P
);
576 ------------------------------
577 -- Analyze_Access_Attribute --
578 ------------------------------
580 procedure Analyze_Access_Attribute
is
581 Acc_Type
: Entity_Id
;
586 function Build_Access_Object_Type
(DT
: Entity_Id
) return Entity_Id
;
587 -- Build an access-to-object type whose designated type is DT,
588 -- and whose Ekind is appropriate to the attribute type. The
589 -- type that is constructed is returned as the result.
591 procedure Build_Access_Subprogram_Type
(P
: Node_Id
);
592 -- Build an access to subprogram whose designated type is the type of
593 -- the prefix. If prefix is overloaded, so is the node itself. The
594 -- result is stored in Acc_Type.
596 function OK_Self_Reference
return Boolean;
597 -- An access reference whose prefix is a type can legally appear
598 -- within an aggregate, where it is obtained by expansion of
599 -- a defaulted aggregate. The enclosing aggregate that contains
600 -- the self-referenced is flagged so that the self-reference can
601 -- be expanded into a reference to the target object (see exp_aggr).
603 ------------------------------
604 -- Build_Access_Object_Type --
605 ------------------------------
607 function Build_Access_Object_Type
(DT
: Entity_Id
) return Entity_Id
is
608 Typ
: constant Entity_Id
:=
610 (E_Access_Attribute_Type
, Current_Scope
, Loc
, 'A');
612 Set_Etype
(Typ
, Typ
);
614 Set_Associated_Node_For_Itype
(Typ
, N
);
615 Set_Directly_Designated_Type
(Typ
, DT
);
617 end Build_Access_Object_Type
;
619 ----------------------------------
620 -- Build_Access_Subprogram_Type --
621 ----------------------------------
623 procedure Build_Access_Subprogram_Type
(P
: Node_Id
) is
624 Index
: Interp_Index
;
627 procedure Check_Local_Access
(E
: Entity_Id
);
628 -- Deal with possible access to local subprogram. If we have such
629 -- an access, we set a flag to kill all tracked values on any call
630 -- because this access value may be passed around, and any called
631 -- code might use it to access a local procedure which clobbers a
632 -- tracked value. If the scope is a loop or block, indicate that
633 -- value tracking is disabled for the enclosing subprogram.
635 function Get_Kind
(E
: Entity_Id
) return Entity_Kind
;
636 -- Distinguish between access to regular/protected subprograms
638 ------------------------
639 -- Check_Local_Access --
640 ------------------------
642 procedure Check_Local_Access
(E
: Entity_Id
) is
644 if not Is_Library_Level_Entity
(E
) then
645 Set_Suppress_Value_Tracking_On_Call
(Current_Scope
);
646 Set_Suppress_Value_Tracking_On_Call
647 (Nearest_Dynamic_Scope
(Current_Scope
));
649 end Check_Local_Access
;
655 function Get_Kind
(E
: Entity_Id
) return Entity_Kind
is
657 if Convention
(E
) = Convention_Protected
then
658 return E_Access_Protected_Subprogram_Type
;
660 return E_Access_Subprogram_Type
;
664 -- Start of processing for Build_Access_Subprogram_Type
667 -- In the case of an access to subprogram, use the name of the
668 -- subprogram itself as the designated type. Type-checking in
669 -- this case compares the signatures of the designated types.
671 -- Note: This fragment of the tree is temporarily malformed
672 -- because the correct tree requires an E_Subprogram_Type entity
673 -- as the designated type. In most cases this designated type is
674 -- later overridden by the semantics with the type imposed by the
675 -- context during the resolution phase. In the specific case of
676 -- the expression Address!(Prim'Unrestricted_Access), used to
677 -- initialize slots of dispatch tables, this work will be done by
678 -- the expander (see Exp_Aggr).
680 -- The reason to temporarily add this kind of node to the tree
681 -- instead of a proper E_Subprogram_Type itype, is the following:
682 -- in case of errors found in the source file we report better
683 -- error messages. For example, instead of generating the
686 -- "expected access to subprogram with profile
687 -- defined at line X"
689 -- we currently generate:
691 -- "expected access to function Z defined at line X"
693 Set_Etype
(N
, Any_Type
);
695 if not Is_Overloaded
(P
) then
696 Check_Local_Access
(Entity
(P
));
698 if not Is_Intrinsic_Subprogram
(Entity
(P
)) then
699 Acc_Type
:= Create_Itype
(Get_Kind
(Entity
(P
)), N
);
700 Set_Is_Public
(Acc_Type
, False);
701 Set_Etype
(Acc_Type
, Acc_Type
);
702 Set_Convention
(Acc_Type
, Convention
(Entity
(P
)));
703 Set_Directly_Designated_Type
(Acc_Type
, Entity
(P
));
704 Set_Etype
(N
, Acc_Type
);
705 Freeze_Before
(N
, Acc_Type
);
709 Get_First_Interp
(P
, Index
, It
);
710 while Present
(It
.Nam
) loop
711 Check_Local_Access
(It
.Nam
);
713 if not Is_Intrinsic_Subprogram
(It
.Nam
) then
714 Acc_Type
:= Create_Itype
(Get_Kind
(It
.Nam
), N
);
715 Set_Is_Public
(Acc_Type
, False);
716 Set_Etype
(Acc_Type
, Acc_Type
);
717 Set_Convention
(Acc_Type
, Convention
(It
.Nam
));
718 Set_Directly_Designated_Type
(Acc_Type
, It
.Nam
);
719 Add_One_Interp
(N
, Acc_Type
, Acc_Type
);
720 Freeze_Before
(N
, Acc_Type
);
723 Get_Next_Interp
(Index
, It
);
727 -- Cannot be applied to intrinsic. Looking at the tests above,
728 -- the only way Etype (N) can still be set to Any_Type is if
729 -- Is_Intrinsic_Subprogram was True for some referenced entity.
731 if Etype
(N
) = Any_Type
then
732 Error_Attr_P
("prefix of % attribute cannot be intrinsic");
734 end Build_Access_Subprogram_Type
;
736 ----------------------
737 -- OK_Self_Reference --
738 ----------------------
740 function OK_Self_Reference
return Boolean is
747 (Nkind
(Par
) = N_Component_Association
748 or else Nkind
(Par
) in N_Subexpr
)
750 if Nkind_In
(Par
, N_Aggregate
, N_Extension_Aggregate
) then
751 if Etype
(Par
) = Typ
then
752 Set_Has_Self_Reference
(Par
);
754 -- Check the context: the aggregate must be part of the
755 -- initialization of a type or component, or it is the
756 -- resulting expansion in an initialization procedure.
758 if Is_Init_Proc
(Current_Scope
) then
762 while Present
(Par
) loop
763 if Nkind
(Par
) = N_Full_Type_Declaration
then
778 -- No enclosing aggregate, or not a self-reference
781 end OK_Self_Reference
;
783 -- Start of processing for Analyze_Access_Attribute
786 Check_SPARK_05_Restriction_On_Attribute
;
789 if Nkind
(P
) = N_Character_Literal
then
791 ("prefix of % attribute cannot be enumeration literal");
794 -- Case of access to subprogram
796 if Is_Entity_Name
(P
) and then Is_Overloadable
(Entity
(P
)) then
797 if Has_Pragma_Inline_Always
(Entity
(P
)) then
799 ("prefix of % attribute cannot be Inline_Always subprogram");
801 elsif Aname
= Name_Unchecked_Access
then
802 Error_Attr
("attribute% cannot be applied to a subprogram", P
);
805 -- Issue an error if the prefix denotes an eliminated subprogram
807 Check_For_Eliminated_Subprogram
(P
, Entity
(P
));
809 -- Check for obsolescent subprogram reference
811 Check_Obsolescent_2005_Entity
(Entity
(P
), P
);
813 -- Build the appropriate subprogram type
815 Build_Access_Subprogram_Type
(P
);
817 -- For P'Access or P'Unrestricted_Access, where P is a nested
818 -- subprogram, we might be passing P to another subprogram (but we
819 -- don't check that here), which might call P. P could modify
820 -- local variables, so we need to kill current values. It is
821 -- important not to do this for library-level subprograms, because
822 -- Kill_Current_Values is very inefficient in the case of library
823 -- level packages with lots of tagged types.
825 if Is_Library_Level_Entity
(Entity
(Prefix
(N
))) then
828 -- Do not kill values on nodes initializing dispatch tables
829 -- slots. The construct Prim_Ptr!(Prim'Unrestricted_Access)
830 -- is currently generated by the expander only for this
831 -- purpose. Done to keep the quality of warnings currently
832 -- generated by the compiler (otherwise any declaration of
833 -- a tagged type cleans constant indications from its scope).
835 elsif Nkind
(Parent
(N
)) = N_Unchecked_Type_Conversion
836 and then (Etype
(Parent
(N
)) = RTE
(RE_Prim_Ptr
)
838 Etype
(Parent
(N
)) = RTE
(RE_Size_Ptr
))
839 and then Is_Dispatching_Operation
840 (Directly_Designated_Type
(Etype
(N
)))
848 -- In the static elaboration model, treat the attribute reference
849 -- as a call for elaboration purposes. Suppress this treatment
850 -- under debug flag. In any case, we are all done.
852 if not Dynamic_Elaboration_Checks
and not Debug_Flag_Dot_UU
then
858 -- Component is an operation of a protected type
860 elsif Nkind
(P
) = N_Selected_Component
861 and then Is_Overloadable
(Entity
(Selector_Name
(P
)))
863 if Ekind
(Entity
(Selector_Name
(P
))) = E_Entry
then
864 Error_Attr_P
("prefix of % attribute must be subprogram");
867 Build_Access_Subprogram_Type
(Selector_Name
(P
));
871 -- Deal with incorrect reference to a type, but note that some
872 -- accesses are allowed: references to the current type instance,
873 -- or in Ada 2005 self-referential pointer in a default-initialized
876 if Is_Entity_Name
(P
) then
879 -- The reference may appear in an aggregate that has been expanded
880 -- into a loop. Locate scope of type definition, if any.
882 Scop
:= Current_Scope
;
883 while Ekind
(Scop
) = E_Loop
loop
884 Scop
:= Scope
(Scop
);
887 if Is_Type
(Typ
) then
889 -- OK if we are within the scope of a limited type
890 -- let's mark the component as having per object constraint
892 if Is_Anonymous_Tagged_Base
(Scop
, Typ
) then
900 Q
: Node_Id
:= Parent
(N
);
904 and then Nkind
(Q
) /= N_Component_Declaration
910 Set_Has_Per_Object_Constraint
911 (Defining_Identifier
(Q
), True);
915 if Nkind
(P
) = N_Expanded_Name
then
917 ("current instance prefix must be a direct name", P
);
920 -- If a current instance attribute appears in a component
921 -- constraint it must appear alone; other contexts (spec-
922 -- expressions, within a task body) are not subject to this
925 if not In_Spec_Expression
926 and then not Has_Completion
(Scop
)
928 Nkind_In
(Parent
(N
), N_Discriminant_Association
,
929 N_Index_Or_Discriminant_Constraint
)
932 ("current instance attribute must appear alone", N
);
935 if Is_CPP_Class
(Root_Type
(Typ
)) then
937 ("??current instance unsupported for derivations of "
938 & "'C'P'P types", N
);
941 -- OK if we are in initialization procedure for the type
942 -- in question, in which case the reference to the type
943 -- is rewritten as a reference to the current object.
945 elsif Ekind
(Scop
) = E_Procedure
946 and then Is_Init_Proc
(Scop
)
947 and then Etype
(First_Formal
(Scop
)) = Typ
950 Make_Attribute_Reference
(Loc
,
951 Prefix
=> Make_Identifier
(Loc
, Name_uInit
),
952 Attribute_Name
=> Name_Unrestricted_Access
));
956 -- OK if a task type, this test needs sharpening up ???
958 elsif Is_Task_Type
(Typ
) then
961 -- OK if self-reference in an aggregate in Ada 2005, and
962 -- the reference comes from a copied default expression.
964 -- Note that we check legality of self-reference even if the
965 -- expression comes from source, e.g. when a single component
966 -- association in an aggregate has a box association.
968 elsif Ada_Version
>= Ada_2005
969 and then OK_Self_Reference
973 -- OK if reference to current instance of a protected object
975 elsif Is_Protected_Self_Reference
(P
) then
978 -- Otherwise we have an error case
981 Error_Attr
("% attribute cannot be applied to type", P
);
987 -- If we fall through, we have a normal access to object case
989 -- Unrestricted_Access is (for now) legal wherever an allocator would
990 -- be legal, so its Etype is set to E_Allocator. The expected type
991 -- of the other attributes is a general access type, and therefore
992 -- we label them with E_Access_Attribute_Type.
994 if not Is_Overloaded
(P
) then
995 Acc_Type
:= Build_Access_Object_Type
(P_Type
);
996 Set_Etype
(N
, Acc_Type
);
1000 Index
: Interp_Index
;
1003 Set_Etype
(N
, Any_Type
);
1004 Get_First_Interp
(P
, Index
, It
);
1005 while Present
(It
.Typ
) loop
1006 Acc_Type
:= Build_Access_Object_Type
(It
.Typ
);
1007 Add_One_Interp
(N
, Acc_Type
, Acc_Type
);
1008 Get_Next_Interp
(Index
, It
);
1013 -- Special cases when we can find a prefix that is an entity name
1022 if Is_Entity_Name
(PP
) then
1025 -- If we have an access to an object, and the attribute
1026 -- comes from source, then set the object as potentially
1027 -- source modified. We do this because the resulting access
1028 -- pointer can be used to modify the variable, and we might
1029 -- not detect this, leading to some junk warnings.
1031 -- We only do this for source references, since otherwise
1032 -- we can suppress warnings, e.g. from the unrestricted
1033 -- access generated for validity checks in -gnatVa mode.
1035 if Comes_From_Source
(N
) then
1036 Set_Never_Set_In_Source
(Ent
, False);
1039 -- Mark entity as address taken in the case of
1040 -- 'Unrestricted_Access or subprograms, and kill current
1043 if Aname
= Name_Unrestricted_Access
1044 or else Is_Subprogram
(Ent
)
1046 Set_Address_Taken
(Ent
);
1049 Kill_Current_Values
(Ent
);
1052 elsif Nkind_In
(PP
, N_Selected_Component
,
1053 N_Indexed_Component
)
1063 -- Check for aliased view. We allow a nonaliased prefix when within
1064 -- an instance because the prefix may have been a tagged formal
1065 -- object, which is defined to be aliased even when the actual
1066 -- might not be (other instance cases will have been caught in the
1067 -- generic). Similarly, within an inlined body we know that the
1068 -- attribute is legal in the original subprogram, and therefore
1069 -- legal in the expansion.
1071 if not Is_Aliased_View
(P
)
1072 and then not In_Instance
1073 and then not In_Inlined_Body
1074 and then Comes_From_Source
(N
)
1076 -- Here we have a non-aliased view. This is illegal unless we
1077 -- have the case of Unrestricted_Access, where for now we allow
1078 -- this (we will reject later if expected type is access to an
1079 -- unconstrained array with a thin pointer).
1081 -- No need for an error message on a generated access reference
1082 -- for the controlling argument in a dispatching call: error will
1083 -- be reported when resolving the call.
1085 if Aname
/= Name_Unrestricted_Access
then
1086 Error_Attr_P
("prefix of % attribute must be aliased");
1087 Check_No_Implicit_Aliasing
(P
);
1089 -- For Unrestricted_Access, record that prefix is not aliased
1090 -- to simplify legality check later on.
1093 Set_Non_Aliased_Prefix
(N
);
1096 -- If we have an aliased view, and we have Unrestricted_Access, then
1097 -- output a warning that Unchecked_Access would have been fine, and
1098 -- change the node to be Unchecked_Access.
1101 -- For now, hold off on this change ???
1105 end Analyze_Access_Attribute
;
1107 ----------------------------------
1108 -- Analyze_Attribute_Old_Result --
1109 ----------------------------------
1111 procedure Analyze_Attribute_Old_Result
1112 (Legal
: out Boolean;
1113 Spec_Id
: out Entity_Id
)
1115 procedure Check_Placement_In_Check
(Prag
: Node_Id
);
1116 -- Verify that the attribute appears within pragma Check that mimics
1119 procedure Check_Placement_In_Contract_Cases
(Prag
: Node_Id
);
1120 -- Verify that the attribute appears within a consequence of aspect
1121 -- or pragma Contract_Cases denoted by Prag.
1123 procedure Check_Placement_In_Test_Case
(Prag
: Node_Id
);
1124 -- Verify that the attribute appears within the "Ensures" argument of
1125 -- aspect or pragma Test_Case denoted by Prag.
1129 Encl_Nod
: Node_Id
) return Boolean;
1130 -- Subsidiary to Check_Placemenet_In_XXX. Determine whether arbitrary
1131 -- node Nod is within enclosing node Encl_Nod.
1133 procedure Placement_Error
;
1134 -- Emit a general error when the attributes does not appear in a
1135 -- postcondition-like aspect or pragma.
1137 ------------------------------
1138 -- Check_Placement_In_Check --
1139 ------------------------------
1141 procedure Check_Placement_In_Check
(Prag
: Node_Id
) is
1142 Args
: constant List_Id
:= Pragma_Argument_Associations
(Prag
);
1143 Nam
: constant Name_Id
:= Chars
(Get_Pragma_Arg
(First
(Args
)));
1146 -- The "Name" argument of pragma Check denotes a postcondition
1148 if Nam_In
(Nam
, Name_Post
,
1155 -- Otherwise the placement of the attribute is illegal
1160 end Check_Placement_In_Check
;
1162 ---------------------------------------
1163 -- Check_Placement_In_Contract_Cases --
1164 ---------------------------------------
1166 procedure Check_Placement_In_Contract_Cases
(Prag
: Node_Id
) is
1172 -- Obtain the argument of the aspect or pragma
1174 if Nkind
(Prag
) = N_Aspect_Specification
then
1177 Arg
:= First
(Pragma_Argument_Associations
(Prag
));
1180 Cases
:= Expression
(Arg
);
1182 if Present
(Component_Associations
(Cases
)) then
1183 CCase
:= First
(Component_Associations
(Cases
));
1184 while Present
(CCase
) loop
1186 -- Detect whether the attribute appears within the
1187 -- consequence of the current contract case.
1189 if Nkind
(CCase
) = N_Component_Association
1190 and then Is_Within
(N
, Expression
(CCase
))
1199 -- Otherwise aspect or pragma Contract_Cases is either malformed
1200 -- or the attribute does not appear within a consequence.
1203 ("attribute % must appear in the consequence of a contract case",
1205 end Check_Placement_In_Contract_Cases
;
1207 ----------------------------------
1208 -- Check_Placement_In_Test_Case --
1209 ----------------------------------
1211 procedure Check_Placement_In_Test_Case
(Prag
: Node_Id
) is
1212 Arg
: constant Node_Id
:=
1215 Arg_Nam
=> Name_Ensures
,
1216 From_Aspect
=> Nkind
(Prag
) = N_Aspect_Specification
);
1219 -- Detect whether the attribute appears within the "Ensures"
1220 -- expression of aspect or pragma Test_Case.
1222 if Present
(Arg
) and then Is_Within
(N
, Arg
) then
1227 ("attribute % must appear in the ensures expression of a "
1230 end Check_Placement_In_Test_Case
;
1238 Encl_Nod
: Node_Id
) return Boolean
1244 while Present
(Par
) loop
1245 if Par
= Encl_Nod
then
1248 -- Prevent the search from going too far
1250 elsif Is_Body_Or_Package_Declaration
(Par
) then
1254 Par
:= Parent
(Par
);
1260 ---------------------
1261 -- Placement_Error --
1262 ---------------------
1264 procedure Placement_Error
is
1266 if Aname
= Name_Old
then
1267 Error_Attr
("attribute % can only appear in postcondition", P
);
1269 -- Specialize the error message for attribute 'Result
1273 ("attribute % can only appear in postcondition of function",
1276 end Placement_Error
;
1282 Subp_Decl
: Node_Id
;
1284 -- Start of processing for Analyze_Attribute_Old_Result
1287 -- Assume that the attribute is illegal
1292 -- Traverse the parent chain to find the aspect or pragma where the
1293 -- attribute resides.
1296 while Present
(Prag
) loop
1297 if Nkind_In
(Prag
, N_Aspect_Specification
, N_Pragma
) then
1300 -- Prevent the search from going too far
1302 elsif Is_Body_Or_Package_Declaration
(Prag
) then
1306 Prag
:= Parent
(Prag
);
1309 -- The attribute is allowed to appear only in postcondition-like
1310 -- aspects or pragmas.
1312 if Nkind_In
(Prag
, N_Aspect_Specification
, N_Pragma
) then
1313 if Nkind
(Prag
) = N_Aspect_Specification
then
1314 Prag_Nam
:= Chars
(Identifier
(Prag
));
1316 Prag_Nam
:= Pragma_Name
(Prag
);
1319 if Prag_Nam
= Name_Check
then
1320 Check_Placement_In_Check
(Prag
);
1322 elsif Prag_Nam
= Name_Contract_Cases
then
1323 Check_Placement_In_Contract_Cases
(Prag
);
1325 -- Attribute 'Result is allowed to appear in aspect or pragma
1326 -- [Refined_]Depends (SPARK RM 6.1.5(11)).
1328 elsif Nam_In
(Prag_Nam
, Name_Depends
, Name_Refined_Depends
)
1329 and then Aname
= Name_Result
1333 elsif Nam_In
(Prag_Nam
, Name_Post
,
1340 elsif Prag_Nam
= Name_Test_Case
then
1341 Check_Placement_In_Test_Case
(Prag
);
1348 -- Otherwise the placement of the attribute is illegal
1355 -- Find the related subprogram subject to the aspect or pragma
1357 if Nkind
(Prag
) = N_Aspect_Specification
then
1358 Subp_Decl
:= Parent
(Prag
);
1360 Subp_Decl
:= Find_Related_Declaration_Or_Body
(Prag
);
1363 -- The aspect or pragma where the attribute resides should be
1364 -- associated with a subprogram declaration or a body. If this is not
1365 -- the case, then the aspect or pragma is illegal. Return as analysis
1366 -- cannot be carried out. Note that it is legal to have the aspect
1367 -- appear on a subprogram renaming, when the renamed entity is an
1368 -- attribute reference.
1370 -- Generating C code the internally built nested _postcondition
1371 -- subprograms are inlined; after expanded, inlined aspects are
1372 -- located in the internal block generated by the frontend.
1374 if Nkind
(Subp_Decl
) = N_Block_Statement
1375 and then Modify_Tree_For_C
1376 and then In_Inlined_Body
1380 elsif not Nkind_In
(Subp_Decl
, N_Abstract_Subprogram_Declaration
,
1381 N_Entry_Declaration
,
1382 N_Generic_Subprogram_Declaration
,
1384 N_Subprogram_Body_Stub
,
1385 N_Subprogram_Declaration
,
1386 N_Subprogram_Renaming_Declaration
)
1391 -- If we get here, then the attribute is legal
1394 Spec_Id
:= Unique_Defining_Entity
(Subp_Decl
);
1396 -- When generating C code, nested _postcondition subprograms are
1397 -- inlined by the front end to avoid problems (when unnested) with
1398 -- referenced itypes. Handle that here, since as part of inlining the
1399 -- expander nests subprogram within a dummy procedure named _parent
1400 -- (see Build_Postconditions_Procedure and Build_Body_To_Inline).
1401 -- Hence, in this context, the spec_id of _postconditions is the
1404 if Modify_Tree_For_C
1405 and then Chars
(Spec_Id
) = Name_uParent
1406 and then Chars
(Scope
(Spec_Id
)) = Name_uPostconditions
1408 -- This situation occurs only when preanalyzing the inlined body
1410 pragma Assert
(not Full_Analysis
);
1412 Spec_Id
:= Scope
(Spec_Id
);
1413 pragma Assert
(Is_Inlined
(Spec_Id
));
1415 end Analyze_Attribute_Old_Result
;
1417 ---------------------------------
1418 -- Bad_Attribute_For_Predicate --
1419 ---------------------------------
1421 procedure Bad_Attribute_For_Predicate
is
1423 if Is_Scalar_Type
(P_Type
)
1424 and then Comes_From_Source
(N
)
1426 Error_Msg_Name_1
:= Aname
;
1427 Bad_Predicated_Subtype_Use
1428 ("type& has predicates, attribute % not allowed", N
, P_Type
);
1430 end Bad_Attribute_For_Predicate
;
1432 --------------------------------
1433 -- Check_Array_Or_Scalar_Type --
1434 --------------------------------
1436 procedure Check_Array_Or_Scalar_Type
is
1437 function In_Aspect_Specification
return Boolean;
1438 -- A current instance of a type in an aspect specification is an
1439 -- object and not a type, and therefore cannot be of a scalar type
1440 -- in the prefix of one of the array attributes if the attribute
1441 -- reference is part of an aspect expression.
1443 -----------------------------
1444 -- In_Aspect_Specification --
1445 -----------------------------
1447 function In_Aspect_Specification
return Boolean is
1452 while Present
(P
) loop
1453 if Nkind
(P
) = N_Aspect_Specification
then
1454 return P_Type
= Entity
(P
);
1456 elsif Nkind
(P
) in N_Declaration
then
1464 end In_Aspect_Specification
;
1471 -- Start of processing for Check_Array_Or_Scalar_Type
1474 -- Case of string literal or string literal subtype. These cases
1475 -- cannot arise from legal Ada code, but the expander is allowed
1476 -- to generate them. They require special handling because string
1477 -- literal subtypes do not have standard bounds (the whole idea
1478 -- of these subtypes is to avoid having to generate the bounds)
1480 if Ekind
(P_Type
) = E_String_Literal_Subtype
then
1481 Set_Etype
(N
, Etype
(First_Index
(P_Base_Type
)));
1486 elsif Is_Scalar_Type
(P_Type
) then
1489 if Present
(E1
) then
1490 Error_Attr
("invalid argument in % attribute", E1
);
1492 elsif In_Aspect_Specification
then
1494 ("prefix of % attribute cannot be the current instance of a "
1495 & "scalar type", P
);
1498 Set_Etype
(N
, P_Base_Type
);
1502 -- The following is a special test to allow 'First to apply to
1503 -- private scalar types if the attribute comes from generated
1504 -- code. This occurs in the case of Normalize_Scalars code.
1506 elsif Is_Private_Type
(P_Type
)
1507 and then Present
(Full_View
(P_Type
))
1508 and then Is_Scalar_Type
(Full_View
(P_Type
))
1509 and then not Comes_From_Source
(N
)
1511 Set_Etype
(N
, Implementation_Base_Type
(P_Type
));
1513 -- Array types other than string literal subtypes handled above
1518 -- We know prefix is an array type, or the name of an array
1519 -- object, and that the expression, if present, is static
1520 -- and within the range of the dimensions of the type.
1522 pragma Assert
(Is_Array_Type
(P_Type
));
1523 Index
:= First_Index
(P_Base_Type
);
1527 -- First dimension assumed
1529 Set_Etype
(N
, Base_Type
(Etype
(Index
)));
1532 Dims
:= UI_To_Int
(Intval
(E1
));
1534 for J
in 1 .. Dims
- 1 loop
1538 Set_Etype
(N
, Base_Type
(Etype
(Index
)));
1539 Set_Etype
(E1
, Standard_Integer
);
1542 end Check_Array_Or_Scalar_Type
;
1544 ----------------------
1545 -- Check_Array_Type --
1546 ----------------------
1548 procedure Check_Array_Type
is
1550 -- Dimension number for array attributes
1553 -- If the type is a string literal type, then this must be generated
1554 -- internally, and no further check is required on its legality.
1556 if Ekind
(P_Type
) = E_String_Literal_Subtype
then
1559 -- If the type is a composite, it is an illegal aggregate, no point
1562 elsif P_Type
= Any_Composite
then
1563 raise Bad_Attribute
;
1566 -- Normal case of array type or subtype
1568 Check_Either_E0_Or_E1
;
1571 if Is_Array_Type
(P_Type
) then
1572 if not Is_Constrained
(P_Type
)
1573 and then Is_Entity_Name
(P
)
1574 and then Is_Type
(Entity
(P
))
1576 -- Note: we do not call Error_Attr here, since we prefer to
1577 -- continue, using the relevant index type of the array,
1578 -- even though it is unconstrained. This gives better error
1579 -- recovery behavior.
1581 Error_Msg_Name_1
:= Aname
;
1583 ("prefix for % attribute must be constrained array", P
);
1586 -- The attribute reference freezes the type, and thus the
1587 -- component type, even if the attribute may not depend on the
1588 -- component. Diagnose arrays with incomplete components now.
1589 -- If the prefix is an access to array, this does not freeze
1590 -- the designated type.
1592 if Nkind
(P
) /= N_Explicit_Dereference
then
1593 Check_Fully_Declared
(Component_Type
(P_Type
), P
);
1596 D
:= Number_Dimensions
(P_Type
);
1599 if Is_Private_Type
(P_Type
) then
1600 Error_Attr_P
("prefix for % attribute may not be private type");
1602 elsif Is_Access_Type
(P_Type
)
1603 and then Is_Array_Type
(Designated_Type
(P_Type
))
1604 and then Is_Entity_Name
(P
)
1605 and then Is_Type
(Entity
(P
))
1607 Error_Attr_P
("prefix of % attribute cannot be access type");
1609 elsif Attr_Id
= Attribute_First
1611 Attr_Id
= Attribute_Last
1613 Error_Attr
("invalid prefix for % attribute", P
);
1616 Error_Attr_P
("prefix for % attribute must be array");
1620 if Present
(E1
) then
1621 Resolve
(E1
, Any_Integer
);
1622 Set_Etype
(E1
, Standard_Integer
);
1624 if not Is_OK_Static_Expression
(E1
)
1625 or else Raises_Constraint_Error
(E1
)
1627 Flag_Non_Static_Expr
1628 ("expression for dimension must be static!", E1
);
1631 elsif UI_To_Int
(Expr_Value
(E1
)) > D
1632 or else UI_To_Int
(Expr_Value
(E1
)) < 1
1634 Error_Attr
("invalid dimension number for array type", E1
);
1638 if (Style_Check
and Style_Check_Array_Attribute_Index
)
1639 and then Comes_From_Source
(N
)
1641 Style
.Check_Array_Attribute_Index
(N
, E1
, D
);
1643 end Check_Array_Type
;
1645 -------------------------
1646 -- Check_Asm_Attribute --
1647 -------------------------
1649 procedure Check_Asm_Attribute
is
1654 -- Check first argument is static string expression
1656 Analyze_And_Resolve
(E1
, Standard_String
);
1658 if Etype
(E1
) = Any_Type
then
1661 elsif not Is_OK_Static_Expression
(E1
) then
1662 Flag_Non_Static_Expr
1663 ("constraint argument must be static string expression!", E1
);
1667 -- Check second argument is right type
1669 Analyze_And_Resolve
(E2
, Entity
(P
));
1671 -- Note: that is all we need to do, we don't need to check
1672 -- that it appears in a correct context. The Ada type system
1673 -- will do that for us.
1675 end Check_Asm_Attribute
;
1677 ---------------------
1678 -- Check_Component --
1679 ---------------------
1681 procedure Check_Component
is
1685 if Nkind
(P
) /= N_Selected_Component
1687 (Ekind
(Entity
(Selector_Name
(P
))) /= E_Component
1689 Ekind
(Entity
(Selector_Name
(P
))) /= E_Discriminant
)
1691 Error_Attr_P
("prefix for % attribute must be selected component");
1693 end Check_Component
;
1695 ------------------------------------
1696 -- Check_Decimal_Fixed_Point_Type --
1697 ------------------------------------
1699 procedure Check_Decimal_Fixed_Point_Type
is
1703 if not Is_Decimal_Fixed_Point_Type
(P_Type
) then
1704 Error_Attr_P
("prefix of % attribute must be decimal type");
1706 end Check_Decimal_Fixed_Point_Type
;
1708 -----------------------
1709 -- Check_Dereference --
1710 -----------------------
1712 procedure Check_Dereference
is
1715 -- Case of a subtype mark
1717 if Is_Entity_Name
(P
) and then Is_Type
(Entity
(P
)) then
1721 -- Case of an expression
1725 if Is_Access_Type
(P_Type
) then
1727 -- If there is an implicit dereference, then we must freeze the
1728 -- designated type of the access type, since the type of the
1729 -- referenced array is this type (see AI95-00106).
1731 -- As done elsewhere, freezing must not happen when pre-analyzing
1732 -- a pre- or postcondition or a default value for an object or for
1733 -- a formal parameter.
1735 if not In_Spec_Expression
then
1736 Freeze_Before
(N
, Designated_Type
(P_Type
));
1740 Make_Explicit_Dereference
(Sloc
(P
),
1741 Prefix
=> Relocate_Node
(P
)));
1743 Analyze_And_Resolve
(P
);
1744 P_Type
:= Etype
(P
);
1746 if P_Type
= Any_Type
then
1747 raise Bad_Attribute
;
1750 P_Base_Type
:= Base_Type
(P_Type
);
1752 end Check_Dereference
;
1754 -------------------------
1755 -- Check_Discrete_Type --
1756 -------------------------
1758 procedure Check_Discrete_Type
is
1762 if not Is_Discrete_Type
(P_Type
) then
1763 Error_Attr_P
("prefix of % attribute must be discrete type");
1765 end Check_Discrete_Type
;
1771 procedure Check_E0
is
1773 if Present
(E1
) then
1774 Unexpected_Argument
(E1
);
1782 procedure Check_E1
is
1784 Check_Either_E0_Or_E1
;
1788 -- Special-case attributes that are functions and that appear as
1789 -- the prefix of another attribute. Error is posted on parent.
1791 if Nkind
(Parent
(N
)) = N_Attribute_Reference
1792 and then Nam_In
(Attribute_Name
(Parent
(N
)), Name_Address
,
1796 Error_Msg_Name_1
:= Attribute_Name
(Parent
(N
));
1797 Error_Msg_N
("illegal prefix for % attribute", Parent
(N
));
1798 Set_Etype
(Parent
(N
), Any_Type
);
1799 Set_Entity
(Parent
(N
), Any_Type
);
1800 raise Bad_Attribute
;
1803 Error_Attr
("missing argument for % attribute", N
);
1812 procedure Check_E2
is
1815 Error_Attr
("missing arguments for % attribute (2 required)", N
);
1817 Error_Attr
("missing argument for % attribute (2 required)", N
);
1821 ---------------------------
1822 -- Check_Either_E0_Or_E1 --
1823 ---------------------------
1825 procedure Check_Either_E0_Or_E1
is
1827 if Present
(E2
) then
1828 Unexpected_Argument
(E2
);
1830 end Check_Either_E0_Or_E1
;
1832 ----------------------
1833 -- Check_Enum_Image --
1834 ----------------------
1836 procedure Check_Enum_Image
is
1840 -- When an enumeration type appears in an attribute reference, all
1841 -- literals of the type are marked as referenced. This must only be
1842 -- done if the attribute reference appears in the current source.
1843 -- Otherwise the information on references may differ between a
1844 -- normal compilation and one that performs inlining.
1846 if Is_Enumeration_Type
(P_Base_Type
)
1847 and then In_Extended_Main_Code_Unit
(N
)
1849 Lit
:= First_Literal
(P_Base_Type
);
1850 while Present
(Lit
) loop
1851 Set_Referenced
(Lit
);
1855 end Check_Enum_Image
;
1857 ----------------------------
1858 -- Check_First_Last_Valid --
1859 ----------------------------
1861 procedure Check_First_Last_Valid
is
1863 Check_Discrete_Type
;
1865 -- Freeze the subtype now, so that the following test for predicates
1866 -- works (we set the predicates stuff up at freeze time)
1868 Insert_Actions
(N
, Freeze_Entity
(P_Type
, P
));
1870 -- Now test for dynamic predicate
1872 if Has_Predicates
(P_Type
)
1873 and then not (Has_Static_Predicate
(P_Type
))
1876 ("prefix of % attribute may not have dynamic predicate");
1879 -- Check non-static subtype
1881 if not Is_OK_Static_Subtype
(P_Type
) then
1882 Error_Attr_P
("prefix of % attribute must be a static subtype");
1885 -- Test case for no values
1887 if Expr_Value
(Type_Low_Bound
(P_Type
)) >
1888 Expr_Value
(Type_High_Bound
(P_Type
))
1889 or else (Has_Predicates
(P_Type
)
1891 Is_Empty_List
(Static_Discrete_Predicate
(P_Type
)))
1894 ("prefix of % attribute must be subtype with at least one "
1897 end Check_First_Last_Valid
;
1899 ----------------------------
1900 -- Check_Fixed_Point_Type --
1901 ----------------------------
1903 procedure Check_Fixed_Point_Type
is
1907 if not Is_Fixed_Point_Type
(P_Type
) then
1908 Error_Attr_P
("prefix of % attribute must be fixed point type");
1910 end Check_Fixed_Point_Type
;
1912 ------------------------------
1913 -- Check_Fixed_Point_Type_0 --
1914 ------------------------------
1916 procedure Check_Fixed_Point_Type_0
is
1918 Check_Fixed_Point_Type
;
1920 end Check_Fixed_Point_Type_0
;
1922 -------------------------------
1923 -- Check_Floating_Point_Type --
1924 -------------------------------
1926 procedure Check_Floating_Point_Type
is
1930 if not Is_Floating_Point_Type
(P_Type
) then
1931 Error_Attr_P
("prefix of % attribute must be float type");
1933 end Check_Floating_Point_Type
;
1935 ---------------------------------
1936 -- Check_Floating_Point_Type_0 --
1937 ---------------------------------
1939 procedure Check_Floating_Point_Type_0
is
1941 Check_Floating_Point_Type
;
1943 end Check_Floating_Point_Type_0
;
1945 ---------------------------------
1946 -- Check_Floating_Point_Type_1 --
1947 ---------------------------------
1949 procedure Check_Floating_Point_Type_1
is
1951 Check_Floating_Point_Type
;
1953 end Check_Floating_Point_Type_1
;
1955 ---------------------------------
1956 -- Check_Floating_Point_Type_2 --
1957 ---------------------------------
1959 procedure Check_Floating_Point_Type_2
is
1961 Check_Floating_Point_Type
;
1963 end Check_Floating_Point_Type_2
;
1965 ------------------------
1966 -- Check_Integer_Type --
1967 ------------------------
1969 procedure Check_Integer_Type
is
1973 if not Is_Integer_Type
(P_Type
) then
1974 Error_Attr_P
("prefix of % attribute must be integer type");
1976 end Check_Integer_Type
;
1978 --------------------------------
1979 -- Check_Modular_Integer_Type --
1980 --------------------------------
1982 procedure Check_Modular_Integer_Type
is
1986 if not Is_Modular_Integer_Type
(P_Type
) then
1988 ("prefix of % attribute must be modular integer type");
1990 end Check_Modular_Integer_Type
;
1992 ------------------------
1993 -- Check_Not_CPP_Type --
1994 ------------------------
1996 procedure Check_Not_CPP_Type
is
1998 if Is_Tagged_Type
(Etype
(P
))
1999 and then Convention
(Etype
(P
)) = Convention_CPP
2000 and then Is_CPP_Class
(Root_Type
(Etype
(P
)))
2003 ("invalid use of % attribute with 'C'P'P tagged type");
2005 end Check_Not_CPP_Type
;
2007 -------------------------------
2008 -- Check_Not_Incomplete_Type --
2009 -------------------------------
2011 procedure Check_Not_Incomplete_Type
is
2016 -- Ada 2005 (AI-50217, AI-326): If the prefix is an explicit
2017 -- dereference we have to check wrong uses of incomplete types
2018 -- (other wrong uses are checked at their freezing point).
2020 -- In Ada 2012, incomplete types can appear in subprogram
2021 -- profiles, but formals with incomplete types cannot be the
2022 -- prefix of attributes.
2024 -- Example 1: Limited-with
2026 -- limited with Pkg;
2028 -- type Acc is access Pkg.T;
2030 -- S : Integer := X.all'Size; -- ERROR
2033 -- Example 2: Tagged incomplete
2035 -- type T is tagged;
2036 -- type Acc is access all T;
2038 -- S : constant Integer := X.all'Size; -- ERROR
2039 -- procedure Q (Obj : Integer := X.all'Alignment); -- ERROR
2041 if Ada_Version
>= Ada_2005
2042 and then Nkind
(P
) = N_Explicit_Dereference
2045 while Nkind
(E
) = N_Explicit_Dereference
loop
2051 if From_Limited_With
(Typ
) then
2053 ("prefix of % attribute cannot be an incomplete type");
2055 -- If the prefix is an access type check the designated type
2057 elsif Is_Access_Type
(Typ
)
2058 and then Nkind
(P
) = N_Explicit_Dereference
2060 Typ
:= Directly_Designated_Type
(Typ
);
2063 if Is_Class_Wide_Type
(Typ
) then
2064 Typ
:= Root_Type
(Typ
);
2067 -- A legal use of a shadow entity occurs only when the unit where
2068 -- the non-limited view resides is imported via a regular with
2069 -- clause in the current body. Such references to shadow entities
2070 -- may occur in subprogram formals.
2072 if Is_Incomplete_Type
(Typ
)
2073 and then From_Limited_With
(Typ
)
2074 and then Present
(Non_Limited_View
(Typ
))
2075 and then Is_Legal_Shadow_Entity_In_Body
(Typ
)
2077 Typ
:= Non_Limited_View
(Typ
);
2080 -- If still incomplete, it can be a local incomplete type, or a
2081 -- limited view whose scope is also a limited view.
2083 if Ekind
(Typ
) = E_Incomplete_Type
then
2084 if not From_Limited_With
(Typ
)
2085 and then No
(Full_View
(Typ
))
2088 ("prefix of % attribute cannot be an incomplete type");
2090 -- The limited view may be available indirectly through
2091 -- an intermediate unit. If the non-limited view is available
2092 -- the attribute reference is legal.
2094 elsif From_Limited_With
(Typ
)
2096 (No
(Non_Limited_View
(Typ
))
2097 or else Is_Incomplete_Type
(Non_Limited_View
(Typ
)))
2100 ("prefix of % attribute cannot be an incomplete type");
2104 -- Ada 2012 : formals in bodies may be incomplete, but no attribute
2107 elsif Is_Entity_Name
(P
)
2108 and then Is_Formal
(Entity
(P
))
2109 and then Is_Incomplete_Type
(Etype
(Etype
(P
)))
2112 ("prefix of % attribute cannot be an incomplete type");
2115 if not Is_Entity_Name
(P
)
2116 or else not Is_Type
(Entity
(P
))
2117 or else In_Spec_Expression
2121 Check_Fully_Declared
(P_Type
, P
);
2123 end Check_Not_Incomplete_Type
;
2125 ----------------------------
2126 -- Check_Object_Reference --
2127 ----------------------------
2129 procedure Check_Object_Reference
(P
: Node_Id
) is
2133 -- If we need an object, and we have a prefix that is the name of
2134 -- a function entity, convert it into a function call.
2136 if Is_Entity_Name
(P
)
2137 and then Ekind
(Entity
(P
)) = E_Function
2139 Rtyp
:= Etype
(Entity
(P
));
2142 Make_Function_Call
(Sloc
(P
),
2143 Name
=> Relocate_Node
(P
)));
2145 Analyze_And_Resolve
(P
, Rtyp
);
2147 -- Otherwise we must have an object reference
2149 elsif not Is_Object_Reference
(P
) then
2150 Error_Attr_P
("prefix of % attribute must be object");
2152 end Check_Object_Reference
;
2154 ----------------------------
2155 -- Check_PolyORB_Attribute --
2156 ----------------------------
2158 procedure Check_PolyORB_Attribute
is
2160 Validate_Non_Static_Attribute_Function_Call
;
2165 if Get_PCS_Name
/= Name_PolyORB_DSA
then
2167 ("attribute% requires the 'Poly'O'R'B 'P'C'S", N
);
2169 end Check_PolyORB_Attribute
;
2171 ------------------------
2172 -- Check_Program_Unit --
2173 ------------------------
2175 procedure Check_Program_Unit
is
2177 if Is_Entity_Name
(P
) then
2179 K
: constant Entity_Kind
:= Ekind
(Entity
(P
));
2180 T
: constant Entity_Id
:= Etype
(Entity
(P
));
2183 if K
in Subprogram_Kind
2184 or else K
in Task_Kind
2185 or else K
in Protected_Kind
2186 or else K
= E_Package
2187 or else K
in Generic_Unit_Kind
2188 or else (K
= E_Variable
2192 Is_Protected_Type
(T
)))
2199 Error_Attr_P
("prefix of % attribute must be program unit");
2200 end Check_Program_Unit
;
2202 ---------------------
2203 -- Check_Real_Type --
2204 ---------------------
2206 procedure Check_Real_Type
is
2210 if not Is_Real_Type
(P_Type
) then
2211 Error_Attr_P
("prefix of % attribute must be real type");
2213 end Check_Real_Type
;
2215 -----------------------
2216 -- Check_Scalar_Type --
2217 -----------------------
2219 procedure Check_Scalar_Type
is
2223 if not Is_Scalar_Type
(P_Type
) then
2224 Error_Attr_P
("prefix of % attribute must be scalar type");
2226 end Check_Scalar_Type
;
2228 ------------------------------------------
2229 -- Check_SPARK_05_Restriction_On_Attribute --
2230 ------------------------------------------
2232 procedure Check_SPARK_05_Restriction_On_Attribute
is
2234 Error_Msg_Name_1
:= Aname
;
2235 Check_SPARK_05_Restriction
("attribute % is not allowed", P
);
2236 end Check_SPARK_05_Restriction_On_Attribute
;
2238 ---------------------------
2239 -- Check_Standard_Prefix --
2240 ---------------------------
2242 procedure Check_Standard_Prefix
is
2246 if Nkind
(P
) /= N_Identifier
or else Chars
(P
) /= Name_Standard
then
2247 Error_Attr
("only allowed prefix for % attribute is Standard", P
);
2249 end Check_Standard_Prefix
;
2251 ----------------------------
2252 -- Check_Stream_Attribute --
2253 ----------------------------
2255 procedure Check_Stream_Attribute
(Nam
: TSS_Name_Type
) is
2259 In_Shared_Var_Procs
: Boolean;
2260 -- True when compiling System.Shared_Storage.Shared_Var_Procs body.
2261 -- For this runtime package (always compiled in GNAT mode), we allow
2262 -- stream attributes references for limited types for the case where
2263 -- shared passive objects are implemented using stream attributes,
2264 -- which is the default in GNAT's persistent storage implementation.
2267 Validate_Non_Static_Attribute_Function_Call
;
2269 -- With the exception of 'Input, Stream attributes are procedures,
2270 -- and can only appear at the position of procedure calls. We check
2271 -- for this here, before they are rewritten, to give a more precise
2274 if Nam
= TSS_Stream_Input
then
2277 elsif Is_List_Member
(N
)
2278 and then not Nkind_In
(Parent
(N
), N_Procedure_Call_Statement
,
2285 ("invalid context for attribute%, which is a procedure", N
);
2289 Btyp
:= Implementation_Base_Type
(P_Type
);
2291 -- Stream attributes not allowed on limited types unless the
2292 -- attribute reference was generated by the expander (in which
2293 -- case the underlying type will be used, as described in Sinfo),
2294 -- or the attribute was specified explicitly for the type itself
2295 -- or one of its ancestors (taking visibility rules into account if
2296 -- in Ada 2005 mode), or a pragma Stream_Convert applies to Btyp
2297 -- (with no visibility restriction).
2300 Gen_Body
: constant Node_Id
:= Enclosing_Generic_Body
(N
);
2302 if Present
(Gen_Body
) then
2303 In_Shared_Var_Procs
:=
2304 Is_RTE
(Corresponding_Spec
(Gen_Body
), RE_Shared_Var_Procs
);
2306 In_Shared_Var_Procs
:= False;
2310 if (Comes_From_Source
(N
)
2311 and then not (In_Shared_Var_Procs
or In_Instance
))
2312 and then not Stream_Attribute_Available
(P_Type
, Nam
)
2313 and then not Has_Rep_Pragma
(Btyp
, Name_Stream_Convert
)
2315 Error_Msg_Name_1
:= Aname
;
2317 if Is_Limited_Type
(P_Type
) then
2319 ("limited type& has no% attribute", P
, P_Type
);
2320 Explain_Limited_Type
(P_Type
, P
);
2323 ("attribute% for type& is not available", P
, P_Type
);
2327 -- Check for no stream operations allowed from No_Tagged_Streams
2329 if Is_Tagged_Type
(P_Type
)
2330 and then Present
(No_Tagged_Streams_Pragma
(P_Type
))
2332 Error_Msg_Sloc
:= Sloc
(No_Tagged_Streams_Pragma
(P_Type
));
2334 ("no stream operations for & (No_Tagged_Streams #)", N
, P_Type
);
2338 -- Check restriction violations
2340 -- First check the No_Streams restriction, which prohibits the use
2341 -- of explicit stream attributes in the source program. We do not
2342 -- prevent the occurrence of stream attributes in generated code,
2343 -- for instance those generated implicitly for dispatching purposes.
2345 if Comes_From_Source
(N
) then
2346 Check_Restriction
(No_Streams
, P
);
2349 -- AI05-0057: if restriction No_Default_Stream_Attributes is active,
2350 -- it is illegal to use a predefined elementary type stream attribute
2351 -- either by itself, or more importantly as part of the attribute
2352 -- subprogram for a composite type. However, if the broader
2353 -- restriction No_Streams is active, stream operations are not
2354 -- generated, and there is no error.
2356 if Restriction_Active
(No_Default_Stream_Attributes
)
2357 and then not Restriction_Active
(No_Streams
)
2363 if Nam
= TSS_Stream_Input
2365 Nam
= TSS_Stream_Read
2368 Type_Without_Stream_Operation
(P_Type
, TSS_Stream_Read
);
2371 Type_Without_Stream_Operation
(P_Type
, TSS_Stream_Write
);
2375 Check_Restriction
(No_Default_Stream_Attributes
, N
);
2378 ("missing user-defined Stream Read or Write for type&",
2380 if not Is_Elementary_Type
(P_Type
) then
2382 ("\which is a component of type&", N
, P_Type
);
2388 -- Check special case of Exception_Id and Exception_Occurrence which
2389 -- are not allowed for restriction No_Exception_Registration.
2391 if Restriction_Check_Required
(No_Exception_Registration
)
2392 and then (Is_RTE
(P_Type
, RE_Exception_Id
)
2394 Is_RTE
(P_Type
, RE_Exception_Occurrence
))
2396 Check_Restriction
(No_Exception_Registration
, P
);
2399 -- Here we must check that the first argument is an access type
2400 -- that is compatible with Ada.Streams.Root_Stream_Type'Class.
2402 Analyze_And_Resolve
(E1
);
2405 -- Note: the double call to Root_Type here is needed because the
2406 -- root type of a class-wide type is the corresponding type (e.g.
2407 -- X for X'Class, and we really want to go to the root.)
2409 if not Is_Access_Type
(Etyp
)
2410 or else Root_Type
(Root_Type
(Designated_Type
(Etyp
))) /=
2411 RTE
(RE_Root_Stream_Type
)
2414 ("expected access to Ada.Streams.Root_Stream_Type''Class", E1
);
2417 -- Check that the second argument is of the right type if there is
2418 -- one (the Input attribute has only one argument so this is skipped)
2420 if Present
(E2
) then
2423 if Nam
= TSS_Stream_Read
2424 and then not Is_OK_Variable_For_Out_Formal
(E2
)
2427 ("second argument of % attribute must be a variable", E2
);
2430 Resolve
(E2
, P_Type
);
2434 end Check_Stream_Attribute
;
2436 -------------------------
2437 -- Check_System_Prefix --
2438 -------------------------
2440 procedure Check_System_Prefix
is
2442 if Nkind
(P
) /= N_Identifier
or else Chars
(P
) /= Name_System
then
2443 Error_Attr
("only allowed prefix for % attribute is System", P
);
2445 end Check_System_Prefix
;
2447 -----------------------
2448 -- Check_Task_Prefix --
2449 -----------------------
2451 procedure Check_Task_Prefix
is
2455 -- Ada 2005 (AI-345): Attribute 'Terminated can be applied to
2456 -- task interface class-wide types.
2458 if Is_Task_Type
(Etype
(P
))
2459 or else (Is_Access_Type
(Etype
(P
))
2460 and then Is_Task_Type
(Designated_Type
(Etype
(P
))))
2461 or else (Ada_Version
>= Ada_2005
2462 and then Ekind
(Etype
(P
)) = E_Class_Wide_Type
2463 and then Is_Interface
(Etype
(P
))
2464 and then Is_Task_Interface
(Etype
(P
)))
2469 if Ada_Version
>= Ada_2005
then
2471 ("prefix of % attribute must be a task or a task " &
2472 "interface class-wide object");
2475 Error_Attr_P
("prefix of % attribute must be a task");
2478 end Check_Task_Prefix
;
2484 -- The possibilities are an entity name denoting a type, or an
2485 -- attribute reference that denotes a type (Base or Class). If
2486 -- the type is incomplete, replace it with its full view.
2488 procedure Check_Type
is
2490 if not Is_Entity_Name
(P
)
2491 or else not Is_Type
(Entity
(P
))
2493 Error_Attr_P
("prefix of % attribute must be a type");
2495 elsif Is_Protected_Self_Reference
(P
) then
2497 ("prefix of % attribute denotes current instance "
2498 & "(RM 9.4(21/2))");
2500 elsif Ekind
(Entity
(P
)) = E_Incomplete_Type
2501 and then Present
(Full_View
(Entity
(P
)))
2503 P_Type
:= Full_View
(Entity
(P
));
2504 Set_Entity
(P
, P_Type
);
2508 ---------------------
2509 -- Check_Unit_Name --
2510 ---------------------
2512 procedure Check_Unit_Name
(Nod
: Node_Id
) is
2514 if Nkind
(Nod
) = N_Identifier
then
2517 elsif Nkind_In
(Nod
, N_Selected_Component
, N_Expanded_Name
) then
2518 Check_Unit_Name
(Prefix
(Nod
));
2520 if Nkind
(Selector_Name
(Nod
)) = N_Identifier
then
2525 Error_Attr
("argument for % attribute must be unit name", P
);
2526 end Check_Unit_Name
;
2532 procedure Error_Attr
is
2534 Set_Etype
(N
, Any_Type
);
2535 Set_Entity
(N
, Any_Type
);
2536 raise Bad_Attribute
;
2539 procedure Error_Attr
(Msg
: String; Error_Node
: Node_Id
) is
2541 Error_Msg_Name_1
:= Aname
;
2542 Error_Msg_N
(Msg
, Error_Node
);
2550 procedure Error_Attr_P
(Msg
: String) is
2552 Error_Msg_Name_1
:= Aname
;
2553 Error_Msg_F
(Msg
, P
);
2557 ----------------------------
2558 -- Legal_Formal_Attribute --
2559 ----------------------------
2561 procedure Legal_Formal_Attribute
is
2565 if not Is_Entity_Name
(P
)
2566 or else not Is_Type
(Entity
(P
))
2568 Error_Attr_P
("prefix of % attribute must be generic type");
2570 elsif Is_Generic_Actual_Type
(Entity
(P
))
2572 or else In_Inlined_Body
2576 elsif Is_Generic_Type
(Entity
(P
)) then
2577 if Is_Definite_Subtype
(Entity
(P
)) then
2579 ("prefix of % attribute must be indefinite generic type");
2584 ("prefix of % attribute must be indefinite generic type");
2587 Set_Etype
(N
, Standard_Boolean
);
2588 end Legal_Formal_Attribute
;
2590 ---------------------------------------------------------------
2591 -- Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements --
2592 ---------------------------------------------------------------
2594 procedure Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
is
2598 Check_Not_Incomplete_Type
;
2599 Set_Etype
(N
, Universal_Integer
);
2600 end Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
;
2606 procedure Min_Max
is
2610 Resolve
(E1
, P_Base_Type
);
2611 Resolve
(E2
, P_Base_Type
);
2612 Set_Etype
(N
, P_Base_Type
);
2614 -- Check for comparison on unordered enumeration type
2616 if Bad_Unordered_Enumeration_Reference
(N
, P_Base_Type
) then
2617 Error_Msg_Sloc
:= Sloc
(P_Base_Type
);
2619 ("comparison on unordered enumeration type& declared#?U?",
2624 ------------------------
2625 -- Standard_Attribute --
2626 ------------------------
2628 procedure Standard_Attribute
(Val
: Int
) is
2630 Check_Standard_Prefix
;
2631 Rewrite
(N
, Make_Integer_Literal
(Loc
, Val
));
2633 Set_Is_Static_Expression
(N
, True);
2634 end Standard_Attribute
;
2636 --------------------
2637 -- Uneval_Old_Msg --
2638 --------------------
2640 procedure Uneval_Old_Msg
is
2641 Uneval_Old_Setting
: Character;
2645 -- If from aspect, then Uneval_Old_Setting comes from flags in the
2646 -- N_Aspect_Specification node that corresponds to the attribute.
2648 -- First find the pragma in which we appear (note that at this stage,
2649 -- even if we appeared originally within an aspect specification, we
2650 -- are now within the corresponding pragma).
2654 Prag
:= Parent
(Prag
);
2655 exit when No
(Prag
) or else Nkind
(Prag
) = N_Pragma
;
2658 if Present
(Prag
) then
2659 if Uneval_Old_Accept
(Prag
) then
2660 Uneval_Old_Setting
:= 'A';
2661 elsif Uneval_Old_Warn
(Prag
) then
2662 Uneval_Old_Setting
:= 'W';
2664 Uneval_Old_Setting
:= 'E';
2667 -- If we did not find the pragma, that's odd, just use the setting
2668 -- from Opt.Uneval_Old. Perhaps this is due to a previous error?
2671 Uneval_Old_Setting
:= Opt
.Uneval_Old
;
2674 -- Processing depends on the setting of Uneval_Old
2676 case Uneval_Old_Setting
is
2679 ("prefix of attribute % that is potentially "
2680 & "unevaluated must denote an entity");
2683 Error_Msg_Name_1
:= Aname
;
2685 ("??prefix of attribute % appears in potentially "
2686 & "unevaluated context, exception may be raised", P
);
2692 raise Program_Error
;
2696 -------------------------
2697 -- Unexpected Argument --
2698 -------------------------
2700 procedure Unexpected_Argument
(En
: Node_Id
) is
2702 Error_Attr
("unexpected argument for % attribute", En
);
2703 end Unexpected_Argument
;
2705 -------------------------------------------------
2706 -- Validate_Non_Static_Attribute_Function_Call --
2707 -------------------------------------------------
2709 -- This function should be moved to Sem_Dist ???
2711 procedure Validate_Non_Static_Attribute_Function_Call
is
2713 if In_Preelaborated_Unit
2714 and then not In_Subprogram_Or_Concurrent_Unit
2716 Flag_Non_Static_Expr
2717 ("non-static function call in preelaborated unit!", N
);
2719 end Validate_Non_Static_Attribute_Function_Call
;
2721 -- Start of processing for Analyze_Attribute
2724 -- Immediate return if unrecognized attribute (already diagnosed by
2725 -- parser, so there is nothing more that we need to do).
2727 if not Is_Attribute_Name
(Aname
) then
2728 raise Bad_Attribute
;
2731 Check_Restriction_No_Use_Of_Attribute
(N
);
2733 -- Deal with Ada 83 issues
2735 if Comes_From_Source
(N
) then
2736 if not Attribute_83
(Attr_Id
) then
2737 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
2738 Error_Msg_Name_1
:= Aname
;
2739 Error_Msg_N
("(Ada 83) attribute% is not standard??", N
);
2742 if Attribute_Impl_Def
(Attr_Id
) then
2743 Check_Restriction
(No_Implementation_Attributes
, N
);
2748 -- Deal with Ada 2005 attributes that are implementation attributes
2749 -- because they appear in a version of Ada before Ada 2005, and
2750 -- similarly for Ada 2012 attributes appearing in an earlier version.
2752 if (Attribute_05
(Attr_Id
) and then Ada_Version
< Ada_2005
)
2754 (Attribute_12
(Attr_Id
) and then Ada_Version
< Ada_2012
)
2756 Check_Restriction
(No_Implementation_Attributes
, N
);
2759 -- Remote access to subprogram type access attribute reference needs
2760 -- unanalyzed copy for tree transformation. The analyzed copy is used
2761 -- for its semantic information (whether prefix is a remote subprogram
2762 -- name), the unanalyzed copy is used to construct new subtree rooted
2763 -- with N_Aggregate which represents a fat pointer aggregate.
2765 if Aname
= Name_Access
then
2766 Discard_Node
(Copy_Separate_Tree
(N
));
2769 -- Analyze prefix and exit if error in analysis. If the prefix is an
2770 -- incomplete type, use full view if available. Note that there are
2771 -- some attributes for which we do not analyze the prefix, since the
2772 -- prefix is not a normal name, or else needs special handling.
2774 if Aname
/= Name_Elab_Body
and then
2775 Aname
/= Name_Elab_Spec
and then
2776 Aname
/= Name_Elab_Subp_Body
and then
2777 Aname
/= Name_Enabled
and then
2781 P_Type
:= Etype
(P
);
2783 if Is_Entity_Name
(P
)
2784 and then Present
(Entity
(P
))
2785 and then Is_Type
(Entity
(P
))
2787 if Ekind
(Entity
(P
)) = E_Incomplete_Type
then
2788 P_Type
:= Get_Full_View
(P_Type
);
2789 Set_Entity
(P
, P_Type
);
2790 Set_Etype
(P
, P_Type
);
2792 elsif Entity
(P
) = Current_Scope
2793 and then Is_Record_Type
(Entity
(P
))
2795 -- Use of current instance within the type. Verify that if the
2796 -- attribute appears within a constraint, it yields an access
2797 -- type, other uses are illegal.
2805 and then Nkind
(Parent
(Par
)) /= N_Component_Definition
2807 Par
:= Parent
(Par
);
2811 and then Nkind
(Par
) = N_Subtype_Indication
2813 if Attr_Id
/= Attribute_Access
2814 and then Attr_Id
/= Attribute_Unchecked_Access
2815 and then Attr_Id
/= Attribute_Unrestricted_Access
2818 ("in a constraint the current instance can only "
2819 & "be used with an access attribute", N
);
2826 if P_Type
= Any_Type
then
2827 raise Bad_Attribute
;
2830 P_Base_Type
:= Base_Type
(P_Type
);
2833 -- Analyze expressions that may be present, exiting if an error occurs
2840 E1
:= First
(Exprs
);
2842 -- Skip analysis for case of Restriction_Set, we do not expect
2843 -- the argument to be analyzed in this case.
2845 if Aname
/= Name_Restriction_Set
then
2848 -- Check for missing/bad expression (result of previous error)
2850 if No
(E1
) or else Etype
(E1
) = Any_Type
then
2851 raise Bad_Attribute
;
2857 if Present
(E2
) then
2860 if Etype
(E2
) = Any_Type
then
2861 raise Bad_Attribute
;
2864 if Present
(Next
(E2
)) then
2865 Unexpected_Argument
(Next
(E2
));
2870 -- Cases where prefix must be resolvable by itself
2872 if Is_Overloaded
(P
)
2873 and then Aname
/= Name_Access
2874 and then Aname
/= Name_Address
2875 and then Aname
/= Name_Code_Address
2876 and then Aname
/= Name_Result
2877 and then Aname
/= Name_Unchecked_Access
2879 -- The prefix must be resolvable by itself, without reference to the
2880 -- attribute. One case that requires special handling is a prefix
2881 -- that is a function name, where one interpretation may be a
2882 -- parameterless call. Entry attributes are handled specially below.
2884 if Is_Entity_Name
(P
)
2885 and then not Nam_In
(Aname
, Name_Count
, Name_Caller
)
2887 Check_Parameterless_Call
(P
);
2890 if Is_Overloaded
(P
) then
2892 -- Ada 2005 (AI-345): Since protected and task types have
2893 -- primitive entry wrappers, the attributes Count, and Caller
2894 -- require a context check
2896 if Nam_In
(Aname
, Name_Count
, Name_Caller
) then
2898 Count
: Natural := 0;
2903 Get_First_Interp
(P
, I
, It
);
2904 while Present
(It
.Nam
) loop
2905 if Comes_From_Source
(It
.Nam
) then
2911 Get_Next_Interp
(I
, It
);
2915 Error_Attr
("ambiguous prefix for % attribute", P
);
2917 Set_Is_Overloaded
(P
, False);
2922 Error_Attr
("ambiguous prefix for % attribute", P
);
2927 -- In SPARK, attributes of private types are only allowed if the full
2928 -- type declaration is visible.
2930 -- Note: the check for Present (Entity (P)) defends against some error
2931 -- conditions where the Entity field is not set.
2933 if Is_Entity_Name
(P
) and then Present
(Entity
(P
))
2934 and then Is_Type
(Entity
(P
))
2935 and then Is_Private_Type
(P_Type
)
2936 and then not In_Open_Scopes
(Scope
(P_Type
))
2937 and then not In_Spec_Expression
2939 Check_SPARK_05_Restriction
("invisible attribute of type", N
);
2942 -- Remaining processing depends on attribute
2946 -- Attributes related to Ada 2012 iterators. Attribute specifications
2947 -- exist for these, but they cannot be queried.
2949 when Attribute_Constant_Indexing
2950 | Attribute_Default_Iterator
2951 | Attribute_Implicit_Dereference
2952 | Attribute_Iterator_Element
2953 | Attribute_Iterable
2954 | Attribute_Variable_Indexing
2956 Error_Msg_N
("illegal attribute", N
);
2958 -- Internal attributes used to deal with Ada 2012 delayed aspects. These
2959 -- were already rejected by the parser. Thus they shouldn't appear here.
2961 when Internal_Attribute_Id
=>
2962 raise Program_Error
;
2968 when Attribute_Abort_Signal
=>
2969 Check_Standard_Prefix
;
2970 Rewrite
(N
, New_Occurrence_Of
(Stand
.Abort_Signal
, Loc
));
2977 when Attribute_Access
=>
2978 Analyze_Access_Attribute
;
2979 Check_Not_Incomplete_Type
;
2985 when Attribute_Address
=>
2988 Check_Not_Incomplete_Type
;
2989 Set_Etype
(N
, RTE
(RE_Address
));
2995 when Attribute_Address_Size
=>
2996 Standard_Attribute
(System_Address_Size
);
3002 when Attribute_Adjacent
=>
3003 Check_Floating_Point_Type_2
;
3004 Set_Etype
(N
, P_Base_Type
);
3005 Resolve
(E1
, P_Base_Type
);
3006 Resolve
(E2
, P_Base_Type
);
3012 when Attribute_Aft
=>
3013 Check_Fixed_Point_Type_0
;
3014 Set_Etype
(N
, Universal_Integer
);
3020 when Attribute_Alignment
=>
3022 -- Don't we need more checking here, cf Size ???
3025 Check_Not_Incomplete_Type
;
3027 Set_Etype
(N
, Universal_Integer
);
3033 when Attribute_Asm_Input
=>
3034 Check_Asm_Attribute
;
3036 -- The back end may need to take the address of E2
3038 if Is_Entity_Name
(E2
) then
3039 Set_Address_Taken
(Entity
(E2
));
3042 Set_Etype
(N
, RTE
(RE_Asm_Input_Operand
));
3048 when Attribute_Asm_Output
=>
3049 Check_Asm_Attribute
;
3051 if Etype
(E2
) = Any_Type
then
3054 elsif Aname
= Name_Asm_Output
then
3055 if not Is_Variable
(E2
) then
3057 ("second argument for Asm_Output is not variable", E2
);
3061 Note_Possible_Modification
(E2
, Sure
=> True);
3063 -- The back end may need to take the address of E2
3065 if Is_Entity_Name
(E2
) then
3066 Set_Address_Taken
(Entity
(E2
));
3069 Set_Etype
(N
, RTE
(RE_Asm_Output_Operand
));
3071 -----------------------------
3072 -- Atomic_Always_Lock_Free --
3073 -----------------------------
3075 when Attribute_Atomic_Always_Lock_Free
=>
3078 Set_Etype
(N
, Standard_Boolean
);
3084 -- Note: when the base attribute appears in the context of a subtype
3085 -- mark, the analysis is done by Sem_Ch8.Find_Type, rather than by
3086 -- the following circuit.
3088 when Attribute_Base
=> Base
: declare
3096 if Ada_Version
>= Ada_95
3097 and then not Is_Scalar_Type
(Typ
)
3098 and then not Is_Generic_Type
(Typ
)
3100 Error_Attr_P
("prefix of Base attribute must be scalar type");
3102 elsif Sloc
(Typ
) = Standard_Location
3103 and then Base_Type
(Typ
) = Typ
3104 and then Warn_On_Redundant_Constructs
3106 Error_Msg_NE
-- CODEFIX
3107 ("?r?redundant attribute, & is its own base type", N
, Typ
);
3110 if Nkind
(Parent
(N
)) /= N_Attribute_Reference
then
3111 Error_Msg_Name_1
:= Aname
;
3112 Check_SPARK_05_Restriction
3113 ("attribute% is only allowed as prefix of another attribute", P
);
3116 Set_Etype
(N
, Base_Type
(Entity
(P
)));
3117 Set_Entity
(N
, Base_Type
(Entity
(P
)));
3118 Rewrite
(N
, New_Occurrence_Of
(Entity
(N
), Loc
));
3126 when Attribute_Bit
=>
3129 if not Is_Object_Reference
(P
) then
3130 Error_Attr_P
("prefix for % attribute must be object");
3132 -- What about the access object cases ???
3138 Set_Etype
(N
, Universal_Integer
);
3144 when Attribute_Bit_Order
=>
3148 if not Is_Record_Type
(P_Type
) then
3149 Error_Attr_P
("prefix of % attribute must be record type");
3152 if Bytes_Big_Endian
xor Reverse_Bit_Order
(P_Type
) then
3154 New_Occurrence_Of
(RTE
(RE_High_Order_First
), Loc
));
3157 New_Occurrence_Of
(RTE
(RE_Low_Order_First
), Loc
));
3160 Set_Etype
(N
, RTE
(RE_Bit_Order
));
3163 -- Reset incorrect indication of staticness
3165 Set_Is_Static_Expression
(N
, False);
3171 -- Note: in generated code, we can have a Bit_Position attribute
3172 -- applied to a (naked) record component (i.e. the prefix is an
3173 -- identifier that references an E_Component or E_Discriminant
3174 -- entity directly, and this is interpreted as expected by Gigi.
3175 -- The following code will not tolerate such usage, but when the
3176 -- expander creates this special case, it marks it as analyzed
3177 -- immediately and sets an appropriate type.
3179 when Attribute_Bit_Position
=>
3180 if Comes_From_Source
(N
) then
3184 Set_Etype
(N
, Universal_Integer
);
3190 when Attribute_Body_Version
=>
3193 Set_Etype
(N
, RTE
(RE_Version_String
));
3199 when Attribute_Callable
=>
3201 Set_Etype
(N
, Standard_Boolean
);
3208 when Attribute_Caller
=> Caller
: declare
3215 if Nkind_In
(P
, N_Identifier
, N_Expanded_Name
) then
3218 if not Is_Entry
(Ent
) then
3219 Error_Attr
("invalid entry name", N
);
3223 Error_Attr
("invalid entry name", N
);
3227 for J
in reverse 0 .. Scope_Stack
.Last
loop
3228 S
:= Scope_Stack
.Table
(J
).Entity
;
3230 if S
= Scope
(Ent
) then
3231 Error_Attr
("Caller must appear in matching accept or body", N
);
3237 Set_Etype
(N
, RTE
(RO_AT_Task_Id
));
3244 when Attribute_Ceiling
=>
3245 Check_Floating_Point_Type_1
;
3246 Set_Etype
(N
, P_Base_Type
);
3247 Resolve
(E1
, P_Base_Type
);
3253 when Attribute_Class
=>
3254 Check_Restriction
(No_Dispatch
, N
);
3258 -- Applying Class to untagged incomplete type is obsolescent in Ada
3259 -- 2005. Note that we can't test Is_Tagged_Type here on P_Type, since
3260 -- this flag gets set by Find_Type in this situation.
3262 if Restriction_Check_Required
(No_Obsolescent_Features
)
3263 and then Ada_Version
>= Ada_2005
3264 and then Ekind
(P_Type
) = E_Incomplete_Type
3267 DN
: constant Node_Id
:= Declaration_Node
(P_Type
);
3269 if Nkind
(DN
) = N_Incomplete_Type_Declaration
3270 and then not Tagged_Present
(DN
)
3272 Check_Restriction
(No_Obsolescent_Features
, P
);
3281 when Attribute_Code_Address
=>
3284 if Nkind
(P
) = N_Attribute_Reference
3285 and then Nam_In
(Attribute_Name
(P
), Name_Elab_Body
, Name_Elab_Spec
)
3289 elsif not Is_Entity_Name
(P
)
3290 or else (Ekind
(Entity
(P
)) /= E_Function
3292 Ekind
(Entity
(P
)) /= E_Procedure
)
3294 Error_Attr
("invalid prefix for % attribute", P
);
3295 Set_Address_Taken
(Entity
(P
));
3297 -- Issue an error if the prefix denotes an eliminated subprogram
3300 Check_For_Eliminated_Subprogram
(P
, Entity
(P
));
3303 Set_Etype
(N
, RTE
(RE_Address
));
3305 ----------------------
3306 -- Compiler_Version --
3307 ----------------------
3309 when Attribute_Compiler_Version
=>
3311 Check_Standard_Prefix
;
3312 Rewrite
(N
, Make_String_Literal
(Loc
, "GNAT " & Gnat_Version_String
));
3313 Analyze_And_Resolve
(N
, Standard_String
);
3314 Set_Is_Static_Expression
(N
, True);
3316 --------------------
3317 -- Component_Size --
3318 --------------------
3320 when Attribute_Component_Size
=>
3322 Set_Etype
(N
, Universal_Integer
);
3324 -- Note: unlike other array attributes, unconstrained arrays are OK
3326 if Is_Array_Type
(P_Type
) and then not Is_Constrained
(P_Type
) then
3336 when Attribute_Compose
=>
3337 Check_Floating_Point_Type_2
;
3338 Set_Etype
(N
, P_Base_Type
);
3339 Resolve
(E1
, P_Base_Type
);
3340 Resolve
(E2
, Any_Integer
);
3346 when Attribute_Constrained
=>
3348 Set_Etype
(N
, Standard_Boolean
);
3350 -- Case from RM J.4(2) of constrained applied to private type
3352 if Is_Entity_Name
(P
) and then Is_Type
(Entity
(P
)) then
3353 Check_Restriction
(No_Obsolescent_Features
, P
);
3355 if Warn_On_Obsolescent_Feature
then
3357 ("constrained for private type is an obsolescent feature "
3358 & "(RM J.4)?j?", N
);
3361 -- If we are within an instance, the attribute must be legal
3362 -- because it was valid in the generic unit. Ditto if this is
3363 -- an inlining of a function declared in an instance.
3365 if In_Instance
or else In_Inlined_Body
then
3368 -- For sure OK if we have a real private type itself, but must
3369 -- be completed, cannot apply Constrained to incomplete type.
3371 elsif Is_Private_Type
(Entity
(P
)) then
3373 -- Note: this is one of the Annex J features that does not
3374 -- generate a warning from -gnatwj, since in fact it seems
3375 -- very useful, and is used in the GNAT runtime.
3377 Check_Not_Incomplete_Type
;
3381 -- Normal (non-obsolescent case) of application to object of
3382 -- a discriminated type.
3385 Check_Object_Reference
(P
);
3387 -- If N does not come from source, then we allow the
3388 -- the attribute prefix to be of a private type whose
3389 -- full type has discriminants. This occurs in cases
3390 -- involving expanded calls to stream attributes.
3392 if not Comes_From_Source
(N
) then
3393 P_Type
:= Underlying_Type
(P_Type
);
3396 -- Must have discriminants or be an access type designating a type
3397 -- with discriminants. If it is a class-wide type it has unknown
3400 if Has_Discriminants
(P_Type
)
3401 or else Has_Unknown_Discriminants
(P_Type
)
3403 (Is_Access_Type
(P_Type
)
3404 and then Has_Discriminants
(Designated_Type
(P_Type
)))
3408 -- The rule given in 3.7.2 is part of static semantics, but the
3409 -- intent is clearly that it be treated as a legality rule, and
3410 -- rechecked in the visible part of an instance. Nevertheless
3411 -- the intent also seems to be it should legally apply to the
3412 -- actual of a formal with unknown discriminants, regardless of
3413 -- whether the actual has discriminants, in which case the value
3414 -- of the attribute is determined using the J.4 rules. This choice
3415 -- seems the most useful, and is compatible with existing tests.
3417 elsif In_Instance
then
3420 -- Also allow an object of a generic type if extensions allowed
3421 -- and allow this for any type at all. (this may be obsolete ???)
3423 elsif (Is_Generic_Type
(P_Type
)
3424 or else Is_Generic_Actual_Type
(P_Type
))
3425 and then Extensions_Allowed
3431 -- Fall through if bad prefix
3434 ("prefix of % attribute must be object of discriminated type");
3440 when Attribute_Copy_Sign
=>
3441 Check_Floating_Point_Type_2
;
3442 Set_Etype
(N
, P_Base_Type
);
3443 Resolve
(E1
, P_Base_Type
);
3444 Resolve
(E2
, P_Base_Type
);
3450 when Attribute_Count
=> Count
: declare
3458 if Nkind_In
(P
, N_Identifier
, N_Expanded_Name
) then
3461 if Ekind
(Ent
) /= E_Entry
then
3462 Error_Attr
("invalid entry name", N
);
3465 elsif Nkind
(P
) = N_Indexed_Component
then
3466 if not Is_Entity_Name
(Prefix
(P
))
3467 or else No
(Entity
(Prefix
(P
)))
3468 or else Ekind
(Entity
(Prefix
(P
))) /= E_Entry_Family
3470 if Nkind
(Prefix
(P
)) = N_Selected_Component
3471 and then Present
(Entity
(Selector_Name
(Prefix
(P
))))
3472 and then Ekind
(Entity
(Selector_Name
(Prefix
(P
)))) =
3476 ("attribute % must apply to entry of current task", P
);
3479 Error_Attr
("invalid entry family name", P
);
3484 Ent
:= Entity
(Prefix
(P
));
3487 elsif Nkind
(P
) = N_Selected_Component
3488 and then Present
(Entity
(Selector_Name
(P
)))
3489 and then Ekind
(Entity
(Selector_Name
(P
))) = E_Entry
3492 ("attribute % must apply to entry of current task", P
);
3495 Error_Attr
("invalid entry name", N
);
3499 for J
in reverse 0 .. Scope_Stack
.Last
loop
3500 S
:= Scope_Stack
.Table
(J
).Entity
;
3502 if S
= Scope
(Ent
) then
3503 if Nkind
(P
) = N_Expanded_Name
then
3504 Tsk
:= Entity
(Prefix
(P
));
3506 -- The prefix denotes either the task type, or else a
3507 -- single task whose task type is being analyzed.
3509 if (Is_Type
(Tsk
) and then Tsk
= S
)
3510 or else (not Is_Type
(Tsk
)
3511 and then Etype
(Tsk
) = S
3512 and then not (Comes_From_Source
(S
)))
3517 ("Attribute % must apply to entry of current task", N
);
3523 elsif Ekind
(Scope
(Ent
)) in Task_Kind
3524 and then not Ekind_In
(S
, E_Block
,
3529 Error_Attr
("Attribute % cannot appear in inner unit", N
);
3531 elsif Ekind
(Scope
(Ent
)) = E_Protected_Type
3532 and then not Has_Completion
(Scope
(Ent
))
3534 Error_Attr
("attribute % can only be used inside body", N
);
3538 if Is_Overloaded
(P
) then
3540 Index
: Interp_Index
;
3544 Get_First_Interp
(P
, Index
, It
);
3545 while Present
(It
.Nam
) loop
3546 if It
.Nam
= Ent
then
3549 -- Ada 2005 (AI-345): Do not consider primitive entry
3550 -- wrappers generated for task or protected types.
3552 elsif Ada_Version
>= Ada_2005
3553 and then not Comes_From_Source
(It
.Nam
)
3558 Error_Attr
("ambiguous entry name", N
);
3561 Get_Next_Interp
(Index
, It
);
3566 Set_Etype
(N
, Universal_Integer
);
3569 -----------------------
3570 -- Default_Bit_Order --
3571 -----------------------
3573 when Attribute_Default_Bit_Order
=> Default_Bit_Order
: declare
3574 Target_Default_Bit_Order
: System
.Bit_Order
;
3577 Check_Standard_Prefix
;
3579 if Bytes_Big_Endian
then
3580 Target_Default_Bit_Order
:= System
.High_Order_First
;
3582 Target_Default_Bit_Order
:= System
.Low_Order_First
;
3586 Make_Integer_Literal
(Loc
,
3587 UI_From_Int
(System
.Bit_Order
'Pos (Target_Default_Bit_Order
))));
3589 Set_Etype
(N
, Universal_Integer
);
3590 Set_Is_Static_Expression
(N
);
3591 end Default_Bit_Order
;
3593 ----------------------------------
3594 -- Default_Scalar_Storage_Order --
3595 ----------------------------------
3597 when Attribute_Default_Scalar_Storage_Order
=> Default_SSO
: declare
3598 RE_Default_SSO
: RE_Id
;
3601 Check_Standard_Prefix
;
3603 case Opt
.Default_SSO
is
3605 if Bytes_Big_Endian
then
3606 RE_Default_SSO
:= RE_High_Order_First
;
3608 RE_Default_SSO
:= RE_Low_Order_First
;
3612 RE_Default_SSO
:= RE_High_Order_First
;
3615 RE_Default_SSO
:= RE_Low_Order_First
;
3618 raise Program_Error
;
3621 Rewrite
(N
, New_Occurrence_Of
(RTE
(RE_Default_SSO
), Loc
));
3628 when Attribute_Definite
=>
3629 Legal_Formal_Attribute
;
3635 when Attribute_Delta
=>
3636 Check_Fixed_Point_Type_0
;
3637 Set_Etype
(N
, Universal_Real
);
3643 when Attribute_Denorm
=>
3644 Check_Floating_Point_Type_0
;
3645 Set_Etype
(N
, Standard_Boolean
);
3651 when Attribute_Deref
=>
3654 Resolve
(E1
, RTE
(RE_Address
));
3655 Set_Etype
(N
, P_Type
);
3657 ---------------------
3658 -- Descriptor_Size --
3659 ---------------------
3661 when Attribute_Descriptor_Size
=>
3664 if not Is_Entity_Name
(P
) or else not Is_Type
(Entity
(P
)) then
3665 Error_Attr_P
("prefix of attribute % must denote a type");
3668 Set_Etype
(N
, Universal_Integer
);
3674 when Attribute_Digits
=>
3678 if not Is_Floating_Point_Type
(P_Type
)
3679 and then not Is_Decimal_Fixed_Point_Type
(P_Type
)
3682 ("prefix of % attribute must be float or decimal type");
3685 Set_Etype
(N
, Universal_Integer
);
3691 -- Also handles processing for Elab_Spec and Elab_Subp_Body
3693 when Attribute_Elab_Body
3694 | Attribute_Elab_Spec
3695 | Attribute_Elab_Subp_Body
3698 Check_Unit_Name
(P
);
3699 Set_Etype
(N
, Standard_Void_Type
);
3701 -- We have to manually call the expander in this case to get
3702 -- the necessary expansion (normally attributes that return
3703 -- entities are not expanded).
3711 -- Shares processing with Elab_Body
3717 when Attribute_Elaborated
=>
3719 Check_Unit_Name
(P
);
3720 Set_Etype
(N
, Standard_Boolean
);
3726 when Attribute_Emax
=>
3727 Check_Floating_Point_Type_0
;
3728 Set_Etype
(N
, Universal_Integer
);
3734 when Attribute_Enabled
=>
3735 Check_Either_E0_Or_E1
;
3737 if Present
(E1
) then
3738 if not Is_Entity_Name
(E1
) or else No
(Entity
(E1
)) then
3739 Error_Msg_N
("entity name expected for Enabled attribute", E1
);
3744 if Nkind
(P
) /= N_Identifier
then
3745 Error_Msg_N
("identifier expected (check name)", P
);
3746 elsif Get_Check_Id
(Chars
(P
)) = No_Check_Id
then
3747 Error_Msg_N
("& is not a recognized check name", P
);
3750 Set_Etype
(N
, Standard_Boolean
);
3756 when Attribute_Enum_Rep
=>
3757 if Present
(E1
) then
3759 Check_Discrete_Type
;
3760 Resolve
(E1
, P_Base_Type
);
3762 elsif not Is_Discrete_Type
(Etype
(P
)) then
3763 Error_Attr_P
("prefix of % attribute must be of discrete type");
3766 Set_Etype
(N
, Universal_Integer
);
3772 when Attribute_Enum_Val
=>
3776 if not Is_Enumeration_Type
(P_Type
) then
3777 Error_Attr_P
("prefix of % attribute must be enumeration type");
3780 -- If the enumeration type has a standard representation, the effect
3781 -- is the same as 'Val, so rewrite the attribute as a 'Val.
3783 if not Has_Non_Standard_Rep
(P_Base_Type
) then
3785 Make_Attribute_Reference
(Loc
,
3786 Prefix
=> Relocate_Node
(Prefix
(N
)),
3787 Attribute_Name
=> Name_Val
,
3788 Expressions
=> New_List
(Relocate_Node
(E1
))));
3789 Analyze_And_Resolve
(N
, P_Base_Type
);
3791 -- Non-standard representation case (enumeration with holes)
3795 Resolve
(E1
, Any_Integer
);
3796 Set_Etype
(N
, P_Base_Type
);
3803 when Attribute_Epsilon
=>
3804 Check_Floating_Point_Type_0
;
3805 Set_Etype
(N
, Universal_Real
);
3811 when Attribute_Exponent
=>
3812 Check_Floating_Point_Type_1
;
3813 Set_Etype
(N
, Universal_Integer
);
3814 Resolve
(E1
, P_Base_Type
);
3820 when Attribute_External_Tag
=>
3824 Set_Etype
(N
, Standard_String
);
3826 if not Is_Tagged_Type
(P_Type
) then
3827 Error_Attr_P
("prefix of % attribute must be tagged");
3834 when Attribute_Fast_Math
=>
3835 Check_Standard_Prefix
;
3836 Rewrite
(N
, New_Occurrence_Of
(Boolean_Literals
(Fast_Math
), Loc
));
3838 -----------------------
3839 -- Finalization_Size --
3840 -----------------------
3842 when Attribute_Finalization_Size
=>
3845 -- The prefix denotes an object
3847 if Is_Object_Reference
(P
) then
3848 Check_Object_Reference
(P
);
3850 -- The prefix denotes a type
3852 elsif Is_Entity_Name
(P
) and then Is_Type
(Entity
(P
)) then
3854 Check_Not_Incomplete_Type
;
3856 -- Attribute 'Finalization_Size is not defined for class-wide
3857 -- types because it is not possible to know statically whether
3858 -- a definite type will have controlled components or not.
3860 if Is_Class_Wide_Type
(Etype
(P
)) then
3862 ("prefix of % attribute cannot denote a class-wide type");
3865 -- The prefix denotes an illegal construct
3869 ("prefix of % attribute must be a definite type or an object");
3872 Set_Etype
(N
, Universal_Integer
);
3878 when Attribute_First
=>
3879 Check_Array_Or_Scalar_Type
;
3880 Bad_Attribute_For_Predicate
;
3886 when Attribute_First_Bit
=>
3888 Set_Etype
(N
, Universal_Integer
);
3894 when Attribute_First_Valid
=>
3895 Check_First_Last_Valid
;
3896 Set_Etype
(N
, P_Type
);
3902 when Attribute_Fixed_Value
=>
3904 Check_Fixed_Point_Type
;
3905 Resolve
(E1
, Any_Integer
);
3906 Set_Etype
(N
, P_Base_Type
);
3912 when Attribute_Floor
=>
3913 Check_Floating_Point_Type_1
;
3914 Set_Etype
(N
, P_Base_Type
);
3915 Resolve
(E1
, P_Base_Type
);
3921 when Attribute_Fore
=>
3922 Check_Fixed_Point_Type_0
;
3923 Set_Etype
(N
, Universal_Integer
);
3929 when Attribute_Fraction
=>
3930 Check_Floating_Point_Type_1
;
3931 Set_Etype
(N
, P_Base_Type
);
3932 Resolve
(E1
, P_Base_Type
);
3938 when Attribute_From_Any
=>
3940 Check_PolyORB_Attribute
;
3941 Set_Etype
(N
, P_Base_Type
);
3943 -----------------------
3944 -- Has_Access_Values --
3945 -----------------------
3947 when Attribute_Has_Access_Values
=>
3950 Set_Etype
(N
, Standard_Boolean
);
3952 ----------------------
3953 -- Has_Same_Storage --
3954 ----------------------
3956 when Attribute_Has_Same_Storage
=>
3959 -- The arguments must be objects of any type
3961 Analyze_And_Resolve
(P
);
3962 Analyze_And_Resolve
(E1
);
3963 Check_Object_Reference
(P
);
3964 Check_Object_Reference
(E1
);
3965 Set_Etype
(N
, Standard_Boolean
);
3967 -----------------------
3968 -- Has_Tagged_Values --
3969 -----------------------
3971 when Attribute_Has_Tagged_Values
=>
3974 Set_Etype
(N
, Standard_Boolean
);
3976 -----------------------
3977 -- Has_Discriminants --
3978 -----------------------
3980 when Attribute_Has_Discriminants
=>
3981 Legal_Formal_Attribute
;
3987 when Attribute_Identity
=>
3991 if Etype
(P
) = Standard_Exception_Type
then
3992 Set_Etype
(N
, RTE
(RE_Exception_Id
));
3994 -- Ada 2005 (AI-345): Attribute 'Identity may be applied to task
3995 -- interface class-wide types.
3997 elsif Is_Task_Type
(Etype
(P
))
3998 or else (Is_Access_Type
(Etype
(P
))
3999 and then Is_Task_Type
(Designated_Type
(Etype
(P
))))
4000 or else (Ada_Version
>= Ada_2005
4001 and then Ekind
(Etype
(P
)) = E_Class_Wide_Type
4002 and then Is_Interface
(Etype
(P
))
4003 and then Is_Task_Interface
(Etype
(P
)))
4006 Set_Etype
(N
, RTE
(RO_AT_Task_Id
));
4009 if Ada_Version
>= Ada_2005
then
4011 ("prefix of % attribute must be an exception, a task or a "
4012 & "task interface class-wide object");
4015 ("prefix of % attribute must be a task or an exception");
4023 when Attribute_Image
=>
4024 Check_SPARK_05_Restriction_On_Attribute
;
4026 -- AI12-00124-1 : The ARG has adopted the GNAT semantics of 'Img
4027 -- for scalar types, so that the prefix can be an object and not
4028 -- a type, and there is no need for an argument. Given this vote
4029 -- of confidence from the ARG, simplest is to transform this new
4030 -- usage of 'Image into a reference to 'Img.
4032 if Ada_Version
> Ada_2005
4033 and then Is_Object_Reference
(P
)
4034 and then Is_Scalar_Type
(P_Type
)
4037 Make_Attribute_Reference
(Loc
,
4038 Prefix
=> Relocate_Node
(P
),
4039 Attribute_Name
=> Name_Img
));
4047 Set_Etype
(N
, Standard_String
);
4049 if Is_Real_Type
(P_Type
) then
4050 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
4051 Error_Msg_Name_1
:= Aname
;
4053 ("(Ada 83) % attribute not allowed for real types", N
);
4057 if Is_Enumeration_Type
(P_Type
) then
4058 Check_Restriction
(No_Enumeration_Maps
, N
);
4062 Resolve
(E1
, P_Base_Type
);
4064 Validate_Non_Static_Attribute_Function_Call
;
4066 -- Check restriction No_Fixed_IO. Note the check of Comes_From_Source
4067 -- to avoid giving a duplicate message for Img expanded into Image.
4069 if Restriction_Check_Required
(No_Fixed_IO
)
4070 and then Comes_From_Source
(N
)
4071 and then Is_Fixed_Point_Type
(P_Type
)
4073 Check_Restriction
(No_Fixed_IO
, P
);
4080 when Attribute_Img
=>
4082 Set_Etype
(N
, Standard_String
);
4084 if not Is_Scalar_Type
(P_Type
)
4085 or else (Is_Entity_Name
(P
) and then Is_Type
(Entity
(P
)))
4088 ("prefix of % attribute must be scalar object name");
4093 -- Check restriction No_Fixed_IO
4095 if Restriction_Check_Required
(No_Fixed_IO
)
4096 and then Is_Fixed_Point_Type
(P_Type
)
4098 Check_Restriction
(No_Fixed_IO
, P
);
4105 when Attribute_Input
=>
4107 Check_Stream_Attribute
(TSS_Stream_Input
);
4108 Set_Etype
(N
, P_Base_Type
);
4114 when Attribute_Integer_Value
=>
4117 Resolve
(E1
, Any_Fixed
);
4119 -- Signal an error if argument type is not a specific fixed-point
4120 -- subtype. An error has been signalled already if the argument
4121 -- was not of a fixed-point type.
4123 if Etype
(E1
) = Any_Fixed
and then not Error_Posted
(E1
) then
4124 Error_Attr
("argument of % must be of a fixed-point type", E1
);
4127 Set_Etype
(N
, P_Base_Type
);
4133 when Attribute_Invalid_Value
=>
4136 Set_Etype
(N
, P_Base_Type
);
4137 Invalid_Value_Used
:= True;
4143 when Attribute_Large
=>
4146 Set_Etype
(N
, Universal_Real
);
4152 when Attribute_Last
=>
4153 Check_Array_Or_Scalar_Type
;
4154 Bad_Attribute_For_Predicate
;
4160 when Attribute_Last_Bit
=>
4162 Set_Etype
(N
, Universal_Integer
);
4168 when Attribute_Last_Valid
=>
4169 Check_First_Last_Valid
;
4170 Set_Etype
(N
, P_Type
);
4176 when Attribute_Leading_Part
=>
4177 Check_Floating_Point_Type_2
;
4178 Set_Etype
(N
, P_Base_Type
);
4179 Resolve
(E1
, P_Base_Type
);
4180 Resolve
(E2
, Any_Integer
);
4186 when Attribute_Length
=>
4188 Set_Etype
(N
, Universal_Integer
);
4194 when Attribute_Library_Level
=>
4197 if not Is_Entity_Name
(P
) then
4198 Error_Attr_P
("prefix of % attribute must be an entity name");
4201 if not Inside_A_Generic
then
4202 Set_Boolean_Result
(N
,
4203 Is_Library_Level_Entity
(Entity
(P
)));
4206 Set_Etype
(N
, Standard_Boolean
);
4212 when Attribute_Lock_Free
=>
4214 Set_Etype
(N
, Standard_Boolean
);
4216 if not Is_Protected_Type
(P_Type
) then
4218 ("prefix of % attribute must be a protected object");
4225 when Attribute_Loop_Entry
=> Loop_Entry
: declare
4226 procedure Check_References_In_Prefix
(Loop_Id
: Entity_Id
);
4227 -- Inspect the prefix for any uses of entities declared within the
4228 -- related loop. Loop_Id denotes the loop identifier.
4230 --------------------------------
4231 -- Check_References_In_Prefix --
4232 --------------------------------
4234 procedure Check_References_In_Prefix
(Loop_Id
: Entity_Id
) is
4235 Loop_Decl
: constant Node_Id
:= Label_Construct
(Parent
(Loop_Id
));
4237 function Check_Reference
(Nod
: Node_Id
) return Traverse_Result
;
4238 -- Determine whether a reference mentions an entity declared
4239 -- within the related loop.
4241 function Declared_Within
(Nod
: Node_Id
) return Boolean;
4242 -- Determine whether Nod appears in the subtree of Loop_Decl
4244 ---------------------
4245 -- Check_Reference --
4246 ---------------------
4248 function Check_Reference
(Nod
: Node_Id
) return Traverse_Result
is
4250 if Nkind
(Nod
) = N_Identifier
4251 and then Present
(Entity
(Nod
))
4252 and then Declared_Within
(Declaration_Node
(Entity
(Nod
)))
4255 ("prefix of attribute % cannot reference local entities",
4261 end Check_Reference
;
4263 procedure Check_References
is new Traverse_Proc
(Check_Reference
);
4265 ---------------------
4266 -- Declared_Within --
4267 ---------------------
4269 function Declared_Within
(Nod
: Node_Id
) return Boolean is
4274 while Present
(Stmt
) loop
4275 if Stmt
= Loop_Decl
then
4278 -- Prevent the search from going too far
4280 elsif Is_Body_Or_Package_Declaration
(Stmt
) then
4284 Stmt
:= Parent
(Stmt
);
4288 end Declared_Within
;
4290 -- Start of processing for Check_Prefix_For_Local_References
4293 Check_References
(P
);
4294 end Check_References_In_Prefix
;
4298 Context
: constant Node_Id
:= Parent
(N
);
4300 Encl_Loop
: Node_Id
;
4301 Encl_Prag
: Node_Id
:= Empty
;
4302 Loop_Id
: Entity_Id
:= Empty
;
4306 -- Start of processing for Loop_Entry
4311 -- Set the type of the attribute now to ensure the successfull
4312 -- continuation of analysis even if the attribute is misplaced.
4314 Set_Etype
(Attr
, P_Type
);
4316 -- Attribute 'Loop_Entry may appear in several flavors:
4318 -- * Prefix'Loop_Entry - in this form, the attribute applies to the
4319 -- nearest enclosing loop.
4321 -- * Prefix'Loop_Entry (Expr) - depending on what Expr denotes, the
4322 -- attribute may be related to a loop denoted by label Expr or
4323 -- the prefix may denote an array object and Expr may act as an
4324 -- indexed component.
4326 -- * Prefix'Loop_Entry (Expr1, ..., ExprN) - the attribute applies
4327 -- to the nearest enclosing loop, all expressions are part of
4328 -- an indexed component.
4330 -- * Prefix'Loop_Entry (Expr) (...) (...) - depending on what Expr
4331 -- denotes, the attribute may be related to a loop denoted by
4332 -- label Expr or the prefix may denote a multidimensional array
4333 -- array object and Expr along with the rest of the expressions
4334 -- may act as indexed components.
4336 -- Regardless of variations, the attribute reference does not have an
4337 -- expression list. Instead, all available expressions are stored as
4338 -- indexed components.
4340 -- When the attribute is part of an indexed component, find the first
4341 -- expression as it will determine the semantics of 'Loop_Entry.
4343 if Nkind
(Context
) = N_Indexed_Component
then
4344 E1
:= First
(Expressions
(Context
));
4347 -- The attribute reference appears in the following form:
4349 -- Prefix'Loop_Entry (Exp1, Expr2, ..., ExprN) [(...)]
4351 -- In this case, the loop name is omitted and no rewriting is
4354 if Present
(E2
) then
4357 -- The form of the attribute is:
4359 -- Prefix'Loop_Entry (Expr) [(...)]
4361 -- If Expr denotes a loop entry, the whole attribute and indexed
4362 -- component will have to be rewritten to reflect this relation.
4365 pragma Assert
(Present
(E1
));
4367 -- Do not expand the expression as it may have side effects.
4368 -- Simply preanalyze to determine whether it is a loop name or
4371 Preanalyze_And_Resolve
(E1
);
4373 if Is_Entity_Name
(E1
)
4374 and then Present
(Entity
(E1
))
4375 and then Ekind
(Entity
(E1
)) = E_Loop
4377 Loop_Id
:= Entity
(E1
);
4379 -- Transform the attribute and enclosing indexed component
4381 Set_Expressions
(N
, Expressions
(Context
));
4382 Rewrite
(Context
, N
);
4383 Set_Etype
(Context
, P_Type
);
4390 -- The prefix must denote an object
4392 if not Is_Object_Reference
(P
) then
4393 Error_Attr_P
("prefix of attribute % must denote an object");
4396 -- The prefix cannot be of a limited type because the expansion of
4397 -- Loop_Entry must create a constant initialized by the evaluated
4400 if Is_Limited_View
(Etype
(P
)) then
4401 Error_Attr_P
("prefix of attribute % cannot be limited");
4404 -- Climb the parent chain to verify the location of the attribute and
4405 -- find the enclosing loop.
4408 while Present
(Stmt
) loop
4410 -- Locate the corresponding enclosing pragma. Note that in the
4411 -- case of Assert[And_Cut] and Assume, we have already checked
4412 -- that the pragma appears in an appropriate loop location.
4414 if Nkind
(Original_Node
(Stmt
)) = N_Pragma
4415 and then Nam_In
(Pragma_Name_Unmapped
(Original_Node
(Stmt
)),
4416 Name_Loop_Invariant
,
4419 Name_Assert_And_Cut
,
4422 Encl_Prag
:= Original_Node
(Stmt
);
4424 -- Locate the enclosing loop (if any). Note that Ada 2012 array
4425 -- iteration may be expanded into several nested loops, we are
4426 -- interested in the outermost one which has the loop identifier,
4427 -- and comes from source.
4429 elsif Nkind
(Stmt
) = N_Loop_Statement
4430 and then Present
(Identifier
(Stmt
))
4431 and then Comes_From_Source
(Original_Node
(Stmt
))
4432 and then Nkind
(Original_Node
(Stmt
)) = N_Loop_Statement
4436 -- The original attribute reference may lack a loop name. Use
4437 -- the name of the enclosing loop because it is the related
4440 if No
(Loop_Id
) then
4441 Loop_Id
:= Entity
(Identifier
(Encl_Loop
));
4446 -- Prevent the search from going too far
4448 elsif Is_Body_Or_Package_Declaration
(Stmt
) then
4452 Stmt
:= Parent
(Stmt
);
4455 -- Loop_Entry must appear within a Loop_Assertion pragma (Assert,
4456 -- Assert_And_Cut, Assume count as loop assertion pragmas for this
4457 -- purpose if they appear in an appropriate location in a loop,
4458 -- which was already checked by the top level pragma circuit).
4460 -- Loop_Entry also denotes a value and as such can appear within an
4461 -- expression that is an argument for another loop aspect. In that
4462 -- case it will have been expanded into the corresponding assignment.
4465 and then Nkind
(Parent
(N
)) = N_Assignment_Statement
4466 and then not Comes_From_Source
(Parent
(N
))
4470 elsif No
(Encl_Prag
) then
4471 Error_Attr
("attribute% must appear within appropriate pragma", N
);
4474 -- A Loop_Entry that applies to a given loop statement must not
4475 -- appear within a body of accept statement, if this construct is
4476 -- itself enclosed by the given loop statement.
4478 for Index
in reverse 0 .. Scope_Stack
.Last
loop
4479 Scop
:= Scope_Stack
.Table
(Index
).Entity
;
4481 if Ekind
(Scop
) = E_Loop
and then Scop
= Loop_Id
then
4483 elsif Ekind_In
(Scop
, E_Block
, E_Loop
, E_Return_Statement
) then
4487 ("attribute % cannot appear in body or accept statement", N
);
4492 -- The prefix cannot mention entities declared within the related
4493 -- loop because they will not be visible once the prefix is moved
4494 -- outside the loop.
4496 Check_References_In_Prefix
(Loop_Id
);
4498 -- The prefix must denote a static entity if the pragma does not
4499 -- apply to the innermost enclosing loop statement, or if it appears
4500 -- within a potentially unevaluated epxression.
4502 if Is_Entity_Name
(P
)
4503 or else Nkind
(Parent
(P
)) = N_Object_Renaming_Declaration
4507 elsif Present
(Encl_Loop
)
4508 and then Entity
(Identifier
(Encl_Loop
)) /= Loop_Id
4511 ("prefix of attribute % that applies to outer loop must denote "
4514 elsif Is_Potentially_Unevaluated
(P
) then
4518 -- Replace the Loop_Entry attribute reference by its prefix if the
4519 -- related pragma is ignored. This transformation is OK with respect
4520 -- to typing because Loop_Entry's type is that of its prefix. This
4521 -- early transformation also avoids the generation of a useless loop
4524 if Present
(Encl_Prag
) and then Is_Ignored
(Encl_Prag
) then
4525 Rewrite
(N
, Relocate_Node
(P
));
4526 Preanalyze_And_Resolve
(N
);
4529 Preanalyze_And_Resolve
(P
);
4537 when Attribute_Machine
=>
4538 Check_Floating_Point_Type_1
;
4539 Set_Etype
(N
, P_Base_Type
);
4540 Resolve
(E1
, P_Base_Type
);
4546 when Attribute_Machine_Emax
=>
4547 Check_Floating_Point_Type_0
;
4548 Set_Etype
(N
, Universal_Integer
);
4554 when Attribute_Machine_Emin
=>
4555 Check_Floating_Point_Type_0
;
4556 Set_Etype
(N
, Universal_Integer
);
4558 ----------------------
4559 -- Machine_Mantissa --
4560 ----------------------
4562 when Attribute_Machine_Mantissa
=>
4563 Check_Floating_Point_Type_0
;
4564 Set_Etype
(N
, Universal_Integer
);
4566 -----------------------
4567 -- Machine_Overflows --
4568 -----------------------
4570 when Attribute_Machine_Overflows
=>
4573 Set_Etype
(N
, Standard_Boolean
);
4579 when Attribute_Machine_Radix
=>
4582 Set_Etype
(N
, Universal_Integer
);
4584 ----------------------
4585 -- Machine_Rounding --
4586 ----------------------
4588 when Attribute_Machine_Rounding
=>
4589 Check_Floating_Point_Type_1
;
4590 Set_Etype
(N
, P_Base_Type
);
4591 Resolve
(E1
, P_Base_Type
);
4593 --------------------
4594 -- Machine_Rounds --
4595 --------------------
4597 when Attribute_Machine_Rounds
=>
4600 Set_Etype
(N
, Standard_Boolean
);
4606 when Attribute_Machine_Size
=>
4609 Check_Not_Incomplete_Type
;
4610 Set_Etype
(N
, Universal_Integer
);
4616 when Attribute_Mantissa
=>
4619 Set_Etype
(N
, Universal_Integer
);
4625 when Attribute_Max
=>
4628 ----------------------------------
4629 -- Max_Alignment_For_Allocation --
4630 ----------------------------------
4632 when Attribute_Max_Size_In_Storage_Elements
=>
4633 Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
;
4635 ----------------------------------
4636 -- Max_Size_In_Storage_Elements --
4637 ----------------------------------
4639 when Attribute_Max_Alignment_For_Allocation
=>
4640 Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
;
4642 -----------------------
4643 -- Maximum_Alignment --
4644 -----------------------
4646 when Attribute_Maximum_Alignment
=>
4647 Standard_Attribute
(Ttypes
.Maximum_Alignment
);
4649 --------------------
4650 -- Mechanism_Code --
4651 --------------------
4653 when Attribute_Mechanism_Code
=>
4654 if not Is_Entity_Name
(P
)
4655 or else not Is_Subprogram
(Entity
(P
))
4657 Error_Attr_P
("prefix of % attribute must be subprogram");
4660 Check_Either_E0_Or_E1
;
4662 if Present
(E1
) then
4663 Resolve
(E1
, Any_Integer
);
4664 Set_Etype
(E1
, Standard_Integer
);
4666 if not Is_OK_Static_Expression
(E1
) then
4667 Flag_Non_Static_Expr
4668 ("expression for parameter number must be static!", E1
);
4671 elsif UI_To_Int
(Intval
(E1
)) > Number_Formals
(Entity
(P
))
4672 or else UI_To_Int
(Intval
(E1
)) < 0
4674 Error_Attr
("invalid parameter number for % attribute", E1
);
4678 Set_Etype
(N
, Universal_Integer
);
4684 when Attribute_Min
=>
4691 when Attribute_Mod
=>
4693 -- Note: this attribute is only allowed in Ada 2005 mode, but
4694 -- we do not need to test that here, since Mod is only recognized
4695 -- as an attribute name in Ada 2005 mode during the parse.
4698 Check_Modular_Integer_Type
;
4699 Resolve
(E1
, Any_Integer
);
4700 Set_Etype
(N
, P_Base_Type
);
4706 when Attribute_Model
=>
4707 Check_Floating_Point_Type_1
;
4708 Set_Etype
(N
, P_Base_Type
);
4709 Resolve
(E1
, P_Base_Type
);
4715 when Attribute_Model_Emin
=>
4716 Check_Floating_Point_Type_0
;
4717 Set_Etype
(N
, Universal_Integer
);
4723 when Attribute_Model_Epsilon
=>
4724 Check_Floating_Point_Type_0
;
4725 Set_Etype
(N
, Universal_Real
);
4727 --------------------
4728 -- Model_Mantissa --
4729 --------------------
4731 when Attribute_Model_Mantissa
=>
4732 Check_Floating_Point_Type_0
;
4733 Set_Etype
(N
, Universal_Integer
);
4739 when Attribute_Model_Small
=>
4740 Check_Floating_Point_Type_0
;
4741 Set_Etype
(N
, Universal_Real
);
4747 when Attribute_Modulus
=>
4749 Check_Modular_Integer_Type
;
4750 Set_Etype
(N
, Universal_Integer
);
4752 --------------------
4753 -- Null_Parameter --
4754 --------------------
4756 when Attribute_Null_Parameter
=> Null_Parameter
: declare
4757 Parnt
: constant Node_Id
:= Parent
(N
);
4758 GParnt
: constant Node_Id
:= Parent
(Parnt
);
4760 procedure Bad_Null_Parameter
(Msg
: String);
4761 -- Used if bad Null parameter attribute node is found. Issues
4762 -- given error message, and also sets the type to Any_Type to
4763 -- avoid blowups later on from dealing with a junk node.
4765 procedure Must_Be_Imported
(Proc_Ent
: Entity_Id
);
4766 -- Called to check that Proc_Ent is imported subprogram
4768 ------------------------
4769 -- Bad_Null_Parameter --
4770 ------------------------
4772 procedure Bad_Null_Parameter
(Msg
: String) is
4774 Error_Msg_N
(Msg
, N
);
4775 Set_Etype
(N
, Any_Type
);
4776 end Bad_Null_Parameter
;
4778 ----------------------
4779 -- Must_Be_Imported --
4780 ----------------------
4782 procedure Must_Be_Imported
(Proc_Ent
: Entity_Id
) is
4783 Pent
: constant Entity_Id
:= Ultimate_Alias
(Proc_Ent
);
4786 -- Ignore check if procedure not frozen yet (we will get
4787 -- another chance when the default parameter is reanalyzed)
4789 if not Is_Frozen
(Pent
) then
4792 elsif not Is_Imported
(Pent
) then
4794 ("Null_Parameter can only be used with imported subprogram");
4799 end Must_Be_Imported
;
4801 -- Start of processing for Null_Parameter
4806 Set_Etype
(N
, P_Type
);
4808 -- Case of attribute used as default expression
4810 if Nkind
(Parnt
) = N_Parameter_Specification
then
4811 Must_Be_Imported
(Defining_Entity
(GParnt
));
4813 -- Case of attribute used as actual for subprogram (positional)
4815 elsif Nkind
(Parnt
) in N_Subprogram_Call
4816 and then Is_Entity_Name
(Name
(Parnt
))
4818 Must_Be_Imported
(Entity
(Name
(Parnt
)));
4820 -- Case of attribute used as actual for subprogram (named)
4822 elsif Nkind
(Parnt
) = N_Parameter_Association
4823 and then Nkind
(GParnt
) in N_Subprogram_Call
4824 and then Is_Entity_Name
(Name
(GParnt
))
4826 Must_Be_Imported
(Entity
(Name
(GParnt
)));
4828 -- Not an allowed case
4832 ("Null_Parameter must be actual or default parameter");
4840 when Attribute_Object_Size
=>
4843 Check_Not_Incomplete_Type
;
4844 Set_Etype
(N
, Universal_Integer
);
4850 when Attribute_Old
=> Old
: declare
4851 procedure Check_References_In_Prefix
(Subp_Id
: Entity_Id
);
4852 -- Inspect the contents of the prefix and detect illegal uses of a
4853 -- nested 'Old, attribute 'Result or a use of an entity declared in
4854 -- the related postcondition expression. Subp_Id is the subprogram to
4855 -- which the related postcondition applies.
4857 --------------------------------
4858 -- Check_References_In_Prefix --
4859 --------------------------------
4861 procedure Check_References_In_Prefix
(Subp_Id
: Entity_Id
) is
4862 function Check_Reference
(Nod
: Node_Id
) return Traverse_Result
;
4863 -- Detect attribute 'Old, attribute 'Result of a use of an entity
4864 -- and perform the appropriate semantic check.
4866 ---------------------
4867 -- Check_Reference --
4868 ---------------------
4870 function Check_Reference
(Nod
: Node_Id
) return Traverse_Result
is
4872 -- Attributes 'Old and 'Result cannot appear in the prefix of
4873 -- another attribute 'Old.
4875 if Nkind
(Nod
) = N_Attribute_Reference
4876 and then Nam_In
(Attribute_Name
(Nod
), Name_Old
,
4879 Error_Msg_Name_1
:= Attribute_Name
(Nod
);
4880 Error_Msg_Name_2
:= Name_Old
;
4882 ("attribute % cannot appear in the prefix of attribute %",
4886 -- Entities mentioned within the prefix of attribute 'Old must
4887 -- be global to the related postcondition. If this is not the
4888 -- case, then the scope of the local entity is nested within
4889 -- that of the subprogram.
4891 elsif Is_Entity_Name
(Nod
)
4892 and then Present
(Entity
(Nod
))
4893 and then Scope_Within
(Scope
(Entity
(Nod
)), Subp_Id
)
4896 ("prefix of attribute % cannot reference local entities",
4900 -- Otherwise keep inspecting the prefix
4905 end Check_Reference
;
4907 procedure Check_References
is new Traverse_Proc
(Check_Reference
);
4909 -- Start of processing for Check_References_In_Prefix
4912 Check_References
(P
);
4913 end Check_References_In_Prefix
;
4918 Pref_Id
: Entity_Id
;
4919 Pref_Typ
: Entity_Id
;
4920 Spec_Id
: Entity_Id
;
4922 -- Start of processing for Old
4925 -- The attribute reference is a primary. If any expressions follow,
4926 -- then the attribute reference is an indexable object. Transform the
4927 -- attribute into an indexed component and analyze it.
4929 if Present
(E1
) then
4931 Make_Indexed_Component
(Loc
,
4933 Make_Attribute_Reference
(Loc
,
4934 Prefix
=> Relocate_Node
(P
),
4935 Attribute_Name
=> Name_Old
),
4936 Expressions
=> Expressions
(N
)));
4941 Analyze_Attribute_Old_Result
(Legal
, Spec_Id
);
4943 -- The aspect or pragma where attribute 'Old resides should be
4944 -- associated with a subprogram declaration or a body. If this is not
4945 -- the case, then the aspect or pragma is illegal. Return as analysis
4946 -- cannot be carried out.
4948 -- The exception to this rule is when generating C since in this case
4949 -- postconditions are inlined.
4952 and then Modify_Tree_For_C
4953 and then In_Inlined_Body
4955 Spec_Id
:= Entity
(P
);
4957 elsif not Legal
then
4961 -- The prefix must be preanalyzed as the full analysis will take
4962 -- place during expansion.
4964 Preanalyze_And_Resolve
(P
);
4966 -- Ensure that the prefix does not contain attributes 'Old or 'Result
4968 Check_References_In_Prefix
(Spec_Id
);
4970 -- Set the type of the attribute now to prevent cascaded errors
4972 Pref_Typ
:= Etype
(P
);
4973 Set_Etype
(N
, Pref_Typ
);
4977 if Is_Limited_Type
(Pref_Typ
) then
4978 Error_Attr
("attribute % cannot apply to limited objects", P
);
4981 -- The prefix is a simple name
4983 if Is_Entity_Name
(P
) and then Present
(Entity
(P
)) then
4984 Pref_Id
:= Entity
(P
);
4986 -- Emit a warning when the prefix is a constant. Note that the use
4987 -- of Error_Attr would reset the type of N to Any_Type even though
4988 -- this is a warning. Use Error_Msg_XXX instead.
4990 if Is_Constant_Object
(Pref_Id
) then
4991 Error_Msg_Name_1
:= Name_Old
;
4993 ("??attribute % applied to constant has no effect", P
);
4996 -- Otherwise the prefix is not a simple name
4999 -- Ensure that the prefix of attribute 'Old is an entity when it
5000 -- is potentially unevaluated (6.1.1 (27/3)).
5002 if Is_Potentially_Unevaluated
(N
) then
5005 -- Detect a possible infinite recursion when the prefix denotes
5006 -- the related function.
5008 -- function Func (...) return ...
5009 -- with Post => Func'Old ...;
5011 -- The function may be specified in qualified form X.Y where X is
5012 -- a protected object and Y is a protected function. In that case
5013 -- ensure that the qualified form has an entity.
5015 elsif Nkind
(P
) = N_Function_Call
5016 and then Nkind
(Name
(P
)) in N_Has_Entity
5018 Pref_Id
:= Entity
(Name
(P
));
5020 if Ekind_In
(Spec_Id
, E_Function
, E_Generic_Function
)
5021 and then Pref_Id
= Spec_Id
5023 Error_Msg_Warn
:= SPARK_Mode
/= On
;
5024 Error_Msg_N
("!possible infinite recursion<<", P
);
5025 Error_Msg_N
("\!??Storage_Error ]<<", P
);
5029 -- The prefix of attribute 'Old may refer to a component of a
5030 -- formal parameter. In this case its expansion may generate
5031 -- actual subtypes that are referenced in an inner context and
5032 -- that must be elaborated within the subprogram itself. If the
5033 -- prefix includes a function call, it may involve finalization
5034 -- actions that should be inserted when the attribute has been
5035 -- rewritten as a declaration. Create a declaration for the prefix
5036 -- and insert it at the start of the enclosing subprogram. This is
5037 -- an expansion activity that has to be performed now to prevent
5038 -- out-of-order issues.
5040 -- This expansion is both harmful and not needed in SPARK mode,
5041 -- since the formal verification back end relies on the types of
5042 -- nodes (hence is not robust w.r.t. a change to base type here),
5043 -- and does not suffer from the out-of-order issue described
5044 -- above. Thus, this expansion is skipped in SPARK mode.
5046 -- The expansion is not relevant for discrete types, which will
5047 -- not generate extra declarations, and where use of the base type
5048 -- may lead to spurious errors if context is a case.
5050 if not GNATprove_Mode
then
5051 if not Is_Discrete_Type
(Pref_Typ
) then
5052 Pref_Typ
:= Base_Type
(Pref_Typ
);
5055 Set_Etype
(N
, Pref_Typ
);
5056 Set_Etype
(P
, Pref_Typ
);
5058 Analyze_Dimension
(N
);
5064 ----------------------
5065 -- Overlaps_Storage --
5066 ----------------------
5068 when Attribute_Overlaps_Storage
=>
5071 -- Both arguments must be objects of any type
5073 Analyze_And_Resolve
(P
);
5074 Analyze_And_Resolve
(E1
);
5075 Check_Object_Reference
(P
);
5076 Check_Object_Reference
(E1
);
5077 Set_Etype
(N
, Standard_Boolean
);
5083 when Attribute_Output
=>
5085 Check_Stream_Attribute
(TSS_Stream_Output
);
5086 Set_Etype
(N
, Standard_Void_Type
);
5087 Resolve
(N
, Standard_Void_Type
);
5093 when Attribute_Partition_ID
=>
5096 if P_Type
/= Any_Type
then
5097 if not Is_Library_Level_Entity
(Entity
(P
)) then
5099 ("prefix of % attribute must be library-level entity");
5101 -- The defining entity of prefix should not be declared inside a
5102 -- Pure unit. RM E.1(8). Is_Pure was set during declaration.
5104 elsif Is_Entity_Name
(P
)
5105 and then Is_Pure
(Entity
(P
))
5107 Error_Attr_P
("prefix of% attribute must not be declared pure");
5111 Set_Etype
(N
, Universal_Integer
);
5113 -------------------------
5114 -- Passed_By_Reference --
5115 -------------------------
5117 when Attribute_Passed_By_Reference
=>
5120 Set_Etype
(N
, Standard_Boolean
);
5126 when Attribute_Pool_Address
=>
5128 Set_Etype
(N
, RTE
(RE_Address
));
5134 when Attribute_Pos
=>
5135 Check_Discrete_Type
;
5138 if Is_Boolean_Type
(P_Type
) then
5139 Error_Msg_Name_1
:= Aname
;
5140 Error_Msg_Name_2
:= Chars
(P_Type
);
5141 Check_SPARK_05_Restriction
5142 ("attribute% is not allowed for type%", P
);
5145 Resolve
(E1
, P_Base_Type
);
5146 Set_Etype
(N
, Universal_Integer
);
5152 when Attribute_Position
=>
5154 Set_Etype
(N
, Universal_Integer
);
5160 when Attribute_Pred
=>
5164 if Is_Real_Type
(P_Type
) or else Is_Boolean_Type
(P_Type
) then
5165 Error_Msg_Name_1
:= Aname
;
5166 Error_Msg_Name_2
:= Chars
(P_Type
);
5167 Check_SPARK_05_Restriction
5168 ("attribute% is not allowed for type%", P
);
5171 Resolve
(E1
, P_Base_Type
);
5172 Set_Etype
(N
, P_Base_Type
);
5174 -- Since Pred works on the base type, we normally do no check for the
5175 -- floating-point case, since the base type is unconstrained. But we
5176 -- make an exception in Check_Float_Overflow mode.
5178 if Is_Floating_Point_Type
(P_Type
) then
5179 if not Range_Checks_Suppressed
(P_Base_Type
) then
5180 Set_Do_Range_Check
(E1
);
5183 -- If not modular type, test for overflow check required
5186 if not Is_Modular_Integer_Type
(P_Type
)
5187 and then not Range_Checks_Suppressed
(P_Base_Type
)
5189 Enable_Range_Check
(E1
);
5197 -- Ada 2005 (AI-327): Dynamic ceiling priorities
5199 when Attribute_Priority
=>
5200 if Ada_Version
< Ada_2005
then
5201 Error_Attr
("% attribute is allowed only in Ada 2005 mode", P
);
5206 Check_Restriction
(No_Dynamic_Priorities
, N
);
5208 -- The prefix must be a protected object (AARM D.5.2 (2/2))
5212 if Is_Protected_Type
(Etype
(P
))
5213 or else (Is_Access_Type
(Etype
(P
))
5214 and then Is_Protected_Type
(Designated_Type
(Etype
(P
))))
5216 Resolve
(P
, Etype
(P
));
5218 Error_Attr_P
("prefix of % attribute must be a protected object");
5221 Set_Etype
(N
, Standard_Integer
);
5223 -- Must be called from within a protected procedure or entry of the
5224 -- protected object.
5231 while S
/= Etype
(P
)
5232 and then S
/= Standard_Standard
5237 if S
= Standard_Standard
then
5238 Error_Attr
("the attribute % is only allowed inside protected "
5243 Validate_Non_Static_Attribute_Function_Call
;
5249 when Attribute_Range
=>
5250 Check_Array_Or_Scalar_Type
;
5251 Bad_Attribute_For_Predicate
;
5253 if Ada_Version
= Ada_83
5254 and then Is_Scalar_Type
(P_Type
)
5255 and then Comes_From_Source
(N
)
5258 ("(Ada 83) % attribute not allowed for scalar type", P
);
5265 when Attribute_Result
=> Result
: declare
5266 function Denote_Same_Function
5267 (Pref_Id
: Entity_Id
;
5268 Spec_Id
: Entity_Id
) return Boolean;
5269 -- Determine whether the entity of the prefix Pref_Id denotes the
5270 -- same entity as that of the related subprogram Spec_Id.
5272 --------------------------
5273 -- Denote_Same_Function --
5274 --------------------------
5276 function Denote_Same_Function
5277 (Pref_Id
: Entity_Id
;
5278 Spec_Id
: Entity_Id
) return Boolean
5280 Over_Id
: constant Entity_Id
:= Overridden_Operation
(Spec_Id
);
5281 Subp_Spec
: constant Node_Id
:= Parent
(Spec_Id
);
5284 -- The prefix denotes the related subprogram
5286 if Pref_Id
= Spec_Id
then
5289 -- Account for a special case when attribute 'Result appears in
5290 -- the postcondition of a generic function.
5293 -- function Gen_Func return ...
5294 -- with Post => Gen_Func'Result ...;
5296 -- When the generic function is instantiated, the Chars field of
5297 -- the instantiated prefix still denotes the name of the generic
5298 -- function. Note that any preemptive transformation is impossible
5299 -- without a proper analysis. The structure of the wrapper package
5302 -- package Anon_Gen_Pack is
5303 -- <subtypes and renamings>
5304 -- function Subp_Decl return ...; -- (!)
5305 -- pragma Postcondition (Gen_Func'Result ...); -- (!)
5306 -- function Gen_Func ... renames Subp_Decl;
5307 -- end Anon_Gen_Pack;
5309 elsif Nkind
(Subp_Spec
) = N_Function_Specification
5310 and then Present
(Generic_Parent
(Subp_Spec
))
5311 and then Ekind_In
(Pref_Id
, E_Generic_Function
, E_Function
)
5313 if Generic_Parent
(Subp_Spec
) = Pref_Id
then
5316 elsif Present
(Alias
(Pref_Id
))
5317 and then Alias
(Pref_Id
) = Spec_Id
5322 -- Account for a special case where a primitive of a tagged type
5323 -- inherits a class-wide postcondition from a parent type. In this
5324 -- case the prefix of attribute 'Result denotes the overriding
5327 elsif Present
(Over_Id
) and then Pref_Id
= Over_Id
then
5331 -- Otherwise the prefix does not denote the related subprogram
5334 end Denote_Same_Function
;
5338 In_Inlined_C_Postcondition
: constant Boolean :=
5340 and then In_Inlined_Body
;
5343 Pref_Id
: Entity_Id
;
5344 Spec_Id
: Entity_Id
;
5346 -- Start of processing for Result
5349 -- The attribute reference is a primary. If any expressions follow,
5350 -- then the attribute reference is an indexable object. Transform the
5351 -- attribute into an indexed component and analyze it.
5353 if Present
(E1
) then
5355 Make_Indexed_Component
(Loc
,
5357 Make_Attribute_Reference
(Loc
,
5358 Prefix
=> Relocate_Node
(P
),
5359 Attribute_Name
=> Name_Result
),
5360 Expressions
=> Expressions
(N
)));
5365 Analyze_Attribute_Old_Result
(Legal
, Spec_Id
);
5367 -- The aspect or pragma where attribute 'Result resides should be
5368 -- associated with a subprogram declaration or a body. If this is not
5369 -- the case, then the aspect or pragma is illegal. Return as analysis
5370 -- cannot be carried out.
5372 -- The exception to this rule is when generating C since in this case
5373 -- postconditions are inlined.
5375 if No
(Spec_Id
) and then In_Inlined_C_Postcondition
then
5376 Spec_Id
:= Entity
(P
);
5378 elsif not Legal
then
5382 -- Attribute 'Result is part of a _Postconditions procedure. There is
5383 -- no need to perform the semantic checks below as they were already
5384 -- verified when the attribute was analyzed in its original context.
5385 -- Instead, rewrite the attribute as a reference to formal parameter
5386 -- _Result of the _Postconditions procedure.
5388 if Chars
(Spec_Id
) = Name_uPostconditions
5390 (In_Inlined_C_Postcondition
5391 and then Nkind
(Parent
(Spec_Id
)) = N_Block_Statement
)
5393 Rewrite
(N
, Make_Identifier
(Loc
, Name_uResult
));
5395 -- The type of formal parameter _Result is that of the function
5396 -- encapsulating the _Postconditions procedure. Resolution must
5397 -- be carried out against the function return type.
5399 Analyze_And_Resolve
(N
, Etype
(Scope
(Spec_Id
)));
5401 -- Otherwise attribute 'Result appears in its original context and
5402 -- all semantic checks should be carried out.
5405 -- Verify the legality of the prefix. It must denotes the entity
5406 -- of the related [generic] function.
5408 if Is_Entity_Name
(P
) then
5409 Pref_Id
:= Entity
(P
);
5411 if Ekind_In
(Pref_Id
, E_Function
, E_Generic_Function
)
5412 and then Ekind
(Spec_Id
) = Ekind
(Pref_Id
)
5414 if Denote_Same_Function
(Pref_Id
, Spec_Id
) then
5416 -- Correct the prefix of the attribute when the context
5417 -- is a generic function.
5419 if Pref_Id
/= Spec_Id
then
5420 Rewrite
(P
, New_Occurrence_Of
(Spec_Id
, Loc
));
5424 Set_Etype
(N
, Etype
(Spec_Id
));
5426 -- Otherwise the prefix denotes some unrelated function
5429 Error_Msg_Name_2
:= Chars
(Spec_Id
);
5431 ("incorrect prefix for attribute %, expected %", P
);
5434 -- Otherwise the prefix denotes some other form of subprogram
5439 ("attribute % can only appear in postcondition of "
5443 -- Otherwise the prefix is illegal
5446 Error_Msg_Name_2
:= Chars
(Spec_Id
);
5447 Error_Attr
("incorrect prefix for attribute %, expected %", P
);
5456 when Attribute_Range_Length
=>
5458 Check_Discrete_Type
;
5459 Set_Etype
(N
, Universal_Integer
);
5465 when Attribute_Read
=>
5467 Check_Stream_Attribute
(TSS_Stream_Read
);
5468 Set_Etype
(N
, Standard_Void_Type
);
5469 Resolve
(N
, Standard_Void_Type
);
5470 Note_Possible_Modification
(E2
, Sure
=> True);
5476 when Attribute_Ref
=>
5480 if Nkind
(P
) /= N_Expanded_Name
5481 or else not Is_RTE
(P_Type
, RE_Address
)
5483 Error_Attr_P
("prefix of % attribute must be System.Address");
5486 Analyze_And_Resolve
(E1
, Any_Integer
);
5487 Set_Etype
(N
, RTE
(RE_Address
));
5493 when Attribute_Remainder
=>
5494 Check_Floating_Point_Type_2
;
5495 Set_Etype
(N
, P_Base_Type
);
5496 Resolve
(E1
, P_Base_Type
);
5497 Resolve
(E2
, P_Base_Type
);
5499 ---------------------
5500 -- Restriction_Set --
5501 ---------------------
5503 when Attribute_Restriction_Set
=> Restriction_Set
: declare
5506 Unam
: Unit_Name_Type
;
5511 Check_System_Prefix
;
5513 -- No_Dependence case
5515 if Nkind
(E1
) = N_Parameter_Association
then
5516 pragma Assert
(Chars
(Selector_Name
(E1
)) = Name_No_Dependence
);
5517 U
:= Explicit_Actual_Parameter
(E1
);
5519 if not OK_No_Dependence_Unit_Name
(U
) then
5520 Set_Boolean_Result
(N
, False);
5524 -- See if there is an entry already in the table. That's the
5525 -- case in which we can return True.
5527 for J
in No_Dependences
.First
.. No_Dependences
.Last
loop
5528 if Designate_Same_Unit
(U
, No_Dependences
.Table
(J
).Unit
)
5529 and then No_Dependences
.Table
(J
).Warn
= False
5531 Set_Boolean_Result
(N
, True);
5536 -- If not in the No_Dependence table, result is False
5538 Set_Boolean_Result
(N
, False);
5540 -- In this case, we must ensure that the binder will reject any
5541 -- other unit in the partition that sets No_Dependence for this
5542 -- unit. We do that by making an entry in the special table kept
5543 -- for this purpose (if the entry is not there already).
5545 Unam
:= Get_Spec_Name
(Get_Unit_Name
(U
));
5547 for J
in Restriction_Set_Dependences
.First
..
5548 Restriction_Set_Dependences
.Last
5550 if Restriction_Set_Dependences
.Table
(J
) = Unam
then
5555 Restriction_Set_Dependences
.Append
(Unam
);
5557 -- Normal restriction case
5560 if Nkind
(E1
) /= N_Identifier
then
5561 Set_Boolean_Result
(N
, False);
5562 Error_Attr
("attribute % requires restriction identifier", E1
);
5565 R
:= Get_Restriction_Id
(Process_Restriction_Synonyms
(E1
));
5567 if R
= Not_A_Restriction_Id
then
5568 Set_Boolean_Result
(N
, False);
5569 Error_Msg_Node_1
:= E1
;
5570 Error_Attr
("invalid restriction identifier &", E1
);
5572 elsif R
not in Partition_Boolean_Restrictions
then
5573 Set_Boolean_Result
(N
, False);
5574 Error_Msg_Node_1
:= E1
;
5576 ("& is not a boolean partition-wide restriction", E1
);
5579 if Restriction_Active
(R
) then
5580 Set_Boolean_Result
(N
, True);
5582 Check_Restriction
(R
, N
);
5583 Set_Boolean_Result
(N
, False);
5587 end Restriction_Set
;
5593 when Attribute_Round
=>
5595 Check_Decimal_Fixed_Point_Type
;
5596 Set_Etype
(N
, P_Base_Type
);
5598 -- Because the context is universal_real (3.5.10(12)) it is a
5599 -- legal context for a universal fixed expression. This is the
5600 -- only attribute whose functional description involves U_R.
5602 if Etype
(E1
) = Universal_Fixed
then
5604 Conv
: constant Node_Id
:= Make_Type_Conversion
(Loc
,
5605 Subtype_Mark
=> New_Occurrence_Of
(Universal_Real
, Loc
),
5606 Expression
=> Relocate_Node
(E1
));
5614 Resolve
(E1
, Any_Real
);
5620 when Attribute_Rounding
=>
5621 Check_Floating_Point_Type_1
;
5622 Set_Etype
(N
, P_Base_Type
);
5623 Resolve
(E1
, P_Base_Type
);
5629 when Attribute_Safe_Emax
=>
5630 Check_Floating_Point_Type_0
;
5631 Set_Etype
(N
, Universal_Integer
);
5637 when Attribute_Safe_First
=>
5638 Check_Floating_Point_Type_0
;
5639 Set_Etype
(N
, Universal_Real
);
5645 when Attribute_Safe_Large
=>
5648 Set_Etype
(N
, Universal_Real
);
5654 when Attribute_Safe_Last
=>
5655 Check_Floating_Point_Type_0
;
5656 Set_Etype
(N
, Universal_Real
);
5662 when Attribute_Safe_Small
=>
5665 Set_Etype
(N
, Universal_Real
);
5667 --------------------------
5668 -- Scalar_Storage_Order --
5669 --------------------------
5671 when Attribute_Scalar_Storage_Order
=> Scalar_Storage_Order
: declare
5672 Ent
: Entity_Id
:= Empty
;
5678 if not (Is_Record_Type
(P_Type
) or else Is_Array_Type
(P_Type
)) then
5680 -- In GNAT mode, the attribute applies to generic types as well
5681 -- as composite types, and for non-composite types always returns
5682 -- the default bit order for the target.
5684 if not (GNAT_Mode
and then Is_Generic_Type
(P_Type
))
5685 and then not In_Instance
5688 ("prefix of % attribute must be record or array type");
5690 elsif not Is_Generic_Type
(P_Type
) then
5691 if Bytes_Big_Endian
then
5692 Ent
:= RTE
(RE_High_Order_First
);
5694 Ent
:= RTE
(RE_Low_Order_First
);
5698 elsif Bytes_Big_Endian
xor Reverse_Storage_Order
(P_Type
) then
5699 Ent
:= RTE
(RE_High_Order_First
);
5702 Ent
:= RTE
(RE_Low_Order_First
);
5705 if Present
(Ent
) then
5706 Rewrite
(N
, New_Occurrence_Of
(Ent
, Loc
));
5709 Set_Etype
(N
, RTE
(RE_Bit_Order
));
5712 -- Reset incorrect indication of staticness
5714 Set_Is_Static_Expression
(N
, False);
5715 end Scalar_Storage_Order
;
5721 when Attribute_Scale
=>
5723 Check_Decimal_Fixed_Point_Type
;
5724 Set_Etype
(N
, Universal_Integer
);
5730 when Attribute_Scaling
=>
5731 Check_Floating_Point_Type_2
;
5732 Set_Etype
(N
, P_Base_Type
);
5733 Resolve
(E1
, P_Base_Type
);
5739 when Attribute_Signed_Zeros
=>
5740 Check_Floating_Point_Type_0
;
5741 Set_Etype
(N
, Standard_Boolean
);
5748 | Attribute_VADS_Size
5752 -- If prefix is parameterless function call, rewrite and resolve
5755 if Is_Entity_Name
(P
)
5756 and then Ekind
(Entity
(P
)) = E_Function
5760 -- Similar processing for a protected function call
5762 elsif Nkind
(P
) = N_Selected_Component
5763 and then Ekind
(Entity
(Selector_Name
(P
))) = E_Function
5768 if Is_Object_Reference
(P
) then
5769 Check_Object_Reference
(P
);
5771 elsif Is_Entity_Name
(P
)
5772 and then (Is_Type
(Entity
(P
))
5773 or else Ekind
(Entity
(P
)) = E_Enumeration_Literal
)
5777 elsif Nkind
(P
) = N_Type_Conversion
5778 and then not Comes_From_Source
(P
)
5782 -- Some other compilers allow dubious use of X'???'Size
5784 elsif Relaxed_RM_Semantics
5785 and then Nkind
(P
) = N_Attribute_Reference
5790 Error_Attr_P
("invalid prefix for % attribute");
5793 Check_Not_Incomplete_Type
;
5795 Set_Etype
(N
, Universal_Integer
);
5797 -- If we are processing pragmas Compile_Time_Warning and Compile_
5798 -- Time_Errors after the back end has been called and this occurrence
5799 -- of 'Size is known at compile time then it is safe to perform this
5800 -- evaluation. Needed to perform the static evaluation of the full
5801 -- boolean expression of these pragmas.
5803 if In_Compile_Time_Warning_Or_Error
5804 and then Is_Entity_Name
(P
)
5805 and then (Is_Type
(Entity
(P
))
5806 or else Ekind
(Entity
(P
)) = E_Enumeration_Literal
)
5807 and then Size_Known_At_Compile_Time
(Entity
(P
))
5809 Rewrite
(N
, Make_Integer_Literal
(Sloc
(N
), Esize
(Entity
(P
))));
5817 when Attribute_Small
=>
5820 Set_Etype
(N
, Universal_Real
);
5826 when Attribute_Storage_Pool
5827 | Attribute_Simple_Storage_Pool
5831 if Is_Access_Type
(P_Type
) then
5832 if Ekind
(P_Type
) = E_Access_Subprogram_Type
then
5834 ("cannot use % attribute for access-to-subprogram type");
5837 -- Set appropriate entity
5839 if Present
(Associated_Storage_Pool
(Root_Type
(P_Type
))) then
5840 Set_Entity
(N
, Associated_Storage_Pool
(Root_Type
(P_Type
)));
5842 Set_Entity
(N
, RTE
(RE_Global_Pool_Object
));
5845 if Attr_Id
= Attribute_Storage_Pool
then
5846 if Present
(Get_Rep_Pragma
(Etype
(Entity
(N
)),
5847 Name_Simple_Storage_Pool_Type
))
5849 Error_Msg_Name_1
:= Aname
;
5850 Error_Msg_Warn
:= SPARK_Mode
/= On
;
5852 ("cannot use % attribute for type with simple storage "
5854 Error_Msg_N
("\Program_Error [<<", N
);
5857 (N
, Make_Raise_Program_Error
5858 (Sloc
(N
), Reason
=> PE_Explicit_Raise
));
5861 Set_Etype
(N
, Class_Wide_Type
(RTE
(RE_Root_Storage_Pool
)));
5863 -- In the Simple_Storage_Pool case, verify that the pool entity is
5864 -- actually of a simple storage pool type, and set the attribute's
5865 -- type to the pool object's type.
5868 if not Present
(Get_Rep_Pragma
(Etype
(Entity
(N
)),
5869 Name_Simple_Storage_Pool_Type
))
5872 ("cannot use % attribute for type without simple " &
5876 Set_Etype
(N
, Etype
(Entity
(N
)));
5879 -- Validate_Remote_Access_To_Class_Wide_Type for attribute
5880 -- Storage_Pool since this attribute is not defined for such
5881 -- types (RM E.2.3(22)).
5883 Validate_Remote_Access_To_Class_Wide_Type
(N
);
5886 Error_Attr_P
("prefix of % attribute must be access type");
5893 when Attribute_Storage_Size
=>
5896 if Is_Task_Type
(P_Type
) then
5897 Set_Etype
(N
, Universal_Integer
);
5899 -- Use with tasks is an obsolescent feature
5901 Check_Restriction
(No_Obsolescent_Features
, P
);
5903 elsif Is_Access_Type
(P_Type
) then
5904 if Ekind
(P_Type
) = E_Access_Subprogram_Type
then
5906 ("cannot use % attribute for access-to-subprogram type");
5909 if Is_Entity_Name
(P
)
5910 and then Is_Type
(Entity
(P
))
5913 Set_Etype
(N
, Universal_Integer
);
5915 -- Validate_Remote_Access_To_Class_Wide_Type for attribute
5916 -- Storage_Size since this attribute is not defined for
5917 -- such types (RM E.2.3(22)).
5919 Validate_Remote_Access_To_Class_Wide_Type
(N
);
5921 -- The prefix is allowed to be an implicit dereference of an
5922 -- access value designating a task.
5926 Set_Etype
(N
, Universal_Integer
);
5930 Error_Attr_P
("prefix of % attribute must be access or task type");
5937 when Attribute_Storage_Unit
=>
5938 Standard_Attribute
(Ttypes
.System_Storage_Unit
);
5944 when Attribute_Stream_Size
=>
5948 if Is_Entity_Name
(P
)
5949 and then Is_Elementary_Type
(Entity
(P
))
5951 Set_Etype
(N
, Universal_Integer
);
5953 Error_Attr_P
("invalid prefix for % attribute");
5960 when Attribute_Stub_Type
=>
5964 if Is_Remote_Access_To_Class_Wide_Type
(Base_Type
(P_Type
)) then
5966 -- For a real RACW [sub]type, use corresponding stub type
5968 if not Is_Generic_Type
(P_Type
) then
5971 (Corresponding_Stub_Type
(Base_Type
(P_Type
)), Loc
));
5973 -- For a generic type (that has been marked as an RACW using the
5974 -- Remote_Access_Type aspect or pragma), use a generic RACW stub
5975 -- type. Note that if the actual is not a remote access type, the
5976 -- instantiation will fail.
5979 -- Note: we go to the underlying type here because the view
5980 -- returned by RTE (RE_RACW_Stub_Type) might be incomplete.
5984 (Underlying_Type
(RTE
(RE_RACW_Stub_Type
)), Loc
));
5989 ("prefix of% attribute must be remote access-to-class-wide");
5996 when Attribute_Succ
=>
6000 if Is_Real_Type
(P_Type
) or else Is_Boolean_Type
(P_Type
) then
6001 Error_Msg_Name_1
:= Aname
;
6002 Error_Msg_Name_2
:= Chars
(P_Type
);
6003 Check_SPARK_05_Restriction
6004 ("attribute% is not allowed for type%", P
);
6007 Resolve
(E1
, P_Base_Type
);
6008 Set_Etype
(N
, P_Base_Type
);
6010 -- Since Pred works on the base type, we normally do no check for the
6011 -- floating-point case, since the base type is unconstrained. But we
6012 -- make an exception in Check_Float_Overflow mode.
6014 if Is_Floating_Point_Type
(P_Type
) then
6015 if not Range_Checks_Suppressed
(P_Base_Type
) then
6016 Set_Do_Range_Check
(E1
);
6019 -- If not modular type, test for overflow check required
6022 if not Is_Modular_Integer_Type
(P_Type
)
6023 and then not Range_Checks_Suppressed
(P_Base_Type
)
6025 Enable_Range_Check
(E1
);
6029 --------------------------------
6030 -- System_Allocator_Alignment --
6031 --------------------------------
6033 when Attribute_System_Allocator_Alignment
=>
6034 Standard_Attribute
(Ttypes
.System_Allocator_Alignment
);
6040 when Attribute_Tag
=>
6044 if not Is_Tagged_Type
(P_Type
) then
6045 Error_Attr_P
("prefix of % attribute must be tagged");
6047 -- Next test does not apply to generated code why not, and what does
6048 -- the illegal reference mean???
6050 elsif Is_Object_Reference
(P
)
6051 and then not Is_Class_Wide_Type
(P_Type
)
6052 and then Comes_From_Source
(N
)
6055 ("% attribute can only be applied to objects " &
6056 "of class - wide type");
6059 -- The prefix cannot be an incomplete type. However, references to
6060 -- 'Tag can be generated when expanding interface conversions, and
6063 if Comes_From_Source
(N
) then
6064 Check_Not_Incomplete_Type
;
6067 -- Set appropriate type
6069 Set_Etype
(N
, RTE
(RE_Tag
));
6075 when Attribute_Target_Name
=> Target_Name
: declare
6076 TN
: constant String := Sdefault
.Target_Name
.all;
6080 Check_Standard_Prefix
;
6084 if TN
(TL
) = '/' or else TN
(TL
) = '\' then
6089 Make_String_Literal
(Loc
,
6090 Strval
=> TN
(TN
'First .. TL
)));
6091 Analyze_And_Resolve
(N
, Standard_String
);
6092 Set_Is_Static_Expression
(N
, True);
6099 when Attribute_Terminated
=>
6101 Set_Etype
(N
, Standard_Boolean
);
6108 when Attribute_To_Address
=> To_Address
: declare
6114 Check_System_Prefix
;
6116 Generate_Reference
(RTE
(RE_Address
), P
);
6117 Analyze_And_Resolve
(E1
, Any_Integer
);
6118 Set_Etype
(N
, RTE
(RE_Address
));
6120 if Is_Static_Expression
(E1
) then
6121 Set_Is_Static_Expression
(N
, True);
6124 -- OK static expression case, check range and set appropriate type
6126 if Is_OK_Static_Expression
(E1
) then
6127 Val
:= Expr_Value
(E1
);
6129 if Val
< -(2 ** UI_From_Int
(Standard
'Address_Size - 1))
6131 Val
> 2 ** UI_From_Int
(Standard
'Address_Size) - 1
6133 Error_Attr
("address value out of range for % attribute", E1
);
6136 -- In most cases the expression is a numeric literal or some other
6137 -- address expression, but if it is a declared constant it may be
6138 -- of a compatible type that must be left on the node.
6140 if Is_Entity_Name
(E1
) then
6143 -- Set type to universal integer if negative
6146 Set_Etype
(E1
, Universal_Integer
);
6148 -- Otherwise set type to Unsigned_64 to accomodate max values
6151 Set_Etype
(E1
, Standard_Unsigned_64
);
6155 Set_Is_Static_Expression
(N
, True);
6162 when Attribute_To_Any
=>
6164 Check_PolyORB_Attribute
;
6165 Set_Etype
(N
, RTE
(RE_Any
));
6171 when Attribute_Truncation
=>
6172 Check_Floating_Point_Type_1
;
6173 Resolve
(E1
, P_Base_Type
);
6174 Set_Etype
(N
, P_Base_Type
);
6180 when Attribute_Type_Class
=>
6183 Check_Not_Incomplete_Type
;
6184 Set_Etype
(N
, RTE
(RE_Type_Class
));
6190 when Attribute_TypeCode
=>
6192 Check_PolyORB_Attribute
;
6193 Set_Etype
(N
, RTE
(RE_TypeCode
));
6199 when Attribute_Type_Key
=> Type_Key
: declare
6200 Full_Name
: constant String_Id
:=
6201 Fully_Qualified_Name_String
(Entity
(P
));
6204 -- The computed signature for the type
6207 -- To simplify the handling of mutually recursive types, follow a
6208 -- single dereference link in a composite type.
6210 procedure Compute_Type_Key
(T
: Entity_Id
);
6211 -- Create a CRC integer from the declaration of the type, For a
6212 -- composite type, fold in the representation of its components in
6213 -- recursive fashion. We use directly the source representation of
6214 -- the types involved.
6216 ----------------------
6217 -- Compute_Type_Key --
6218 ----------------------
6220 procedure Compute_Type_Key
(T
: Entity_Id
) is
6221 Buffer
: Source_Buffer_Ptr
;
6225 SFI
: Source_File_Index
;
6227 procedure Process_One_Declaration
;
6228 -- Update CRC with the characters of one type declaration, or a
6229 -- representation pragma that applies to the type.
6231 -----------------------------
6232 -- Process_One_Declaration --
6233 -----------------------------
6235 procedure Process_One_Declaration
is
6241 -- Scan type declaration, skipping blanks
6243 while Ptr
<= P_Max
loop
6244 if Buffer
(Ptr
) /= ' ' then
6245 System
.CRC32
.Update
(CRC
, Buffer
(Ptr
));
6250 end Process_One_Declaration
;
6252 -- Start of processing for Compute_Type_Key
6255 if Is_Itype
(T
) then
6259 Sloc_Range
(Enclosing_Declaration
(T
), P_Min
, P_Max
);
6260 SFI
:= Get_Source_File_Index
(P_Min
);
6261 Buffer
:= Source_Text
(SFI
);
6263 Process_One_Declaration
;
6265 -- Recurse on relevant component types
6267 if Is_Array_Type
(T
) then
6268 Compute_Type_Key
(Component_Type
(T
));
6270 elsif Is_Access_Type
(T
) then
6273 Compute_Type_Key
(Designated_Type
(T
));
6276 elsif Is_Derived_Type
(T
) then
6277 Compute_Type_Key
(Etype
(T
));
6279 elsif Is_Record_Type
(T
) then
6283 Comp
:= First_Component
(T
);
6284 while Present
(Comp
) loop
6285 Compute_Type_Key
(Etype
(Comp
));
6286 Next_Component
(Comp
);
6291 -- Fold in representation aspects for the type, which appear in
6292 -- the same source buffer.
6294 Rep
:= First_Rep_Item
(T
);
6296 while Present
(Rep
) loop
6297 if Comes_From_Source
(Rep
) then
6298 Sloc_Range
(Rep
, P_Min
, P_Max
);
6299 Process_One_Declaration
;
6302 Rep
:= Next_Rep_Item
(Rep
);
6304 end Compute_Type_Key
;
6306 -- Start of processing for Type_Key
6315 -- Copy all characters in Full_Name but the trailing NUL
6317 for J
in 1 .. String_Length
(Full_Name
) - 1 loop
6318 Store_String_Char
(Get_String_Char
(Full_Name
, Pos
(J
)));
6321 -- For standard types return the name of the type, as there is no
6322 -- explicit source declaration to use. Otherwise compute CRC and
6323 -- convert it to string one character at a time, so as not to use
6324 -- Image within the compiler.
6326 if Scope
(Entity
(P
)) /= Standard_Standard
then
6328 Compute_Type_Key
(Entity
(P
));
6330 if not Is_Frozen
(Entity
(P
)) then
6331 Error_Msg_N
("premature usage of Type_Key?", N
);
6335 Store_String_Char
(Character'Val (48 + (CRC
rem 10)));
6340 Rewrite
(N
, Make_String_Literal
(Loc
, End_String
));
6341 Analyze_And_Resolve
(N
, Standard_String
);
6344 -----------------------
6345 -- Unbiased_Rounding --
6346 -----------------------
6348 when Attribute_Unbiased_Rounding
=>
6349 Check_Floating_Point_Type_1
;
6350 Set_Etype
(N
, P_Base_Type
);
6351 Resolve
(E1
, P_Base_Type
);
6353 ----------------------
6354 -- Unchecked_Access --
6355 ----------------------
6357 when Attribute_Unchecked_Access
=>
6358 if Comes_From_Source
(N
) then
6359 Check_Restriction
(No_Unchecked_Access
, N
);
6362 Analyze_Access_Attribute
;
6363 Check_Not_Incomplete_Type
;
6365 -------------------------
6366 -- Unconstrained_Array --
6367 -------------------------
6369 when Attribute_Unconstrained_Array
=>
6372 Check_Not_Incomplete_Type
;
6373 Set_Etype
(N
, Standard_Boolean
);
6374 Set_Is_Static_Expression
(N
, True);
6376 ------------------------------
6377 -- Universal_Literal_String --
6378 ------------------------------
6380 -- This is a GNAT specific attribute whose prefix must be a named
6381 -- number where the expression is either a single numeric literal,
6382 -- or a numeric literal immediately preceded by a minus sign. The
6383 -- result is equivalent to a string literal containing the text of
6384 -- the literal as it appeared in the source program with a possible
6385 -- leading minus sign.
6387 when Attribute_Universal_Literal_String
=>
6390 if not Is_Entity_Name
(P
)
6391 or else Ekind
(Entity
(P
)) not in Named_Kind
6393 Error_Attr_P
("prefix for % attribute must be named number");
6400 Src
: Source_Buffer_Ptr
;
6403 Expr
:= Original_Node
(Expression
(Parent
(Entity
(P
))));
6405 if Nkind
(Expr
) = N_Op_Minus
then
6407 Expr
:= Original_Node
(Right_Opnd
(Expr
));
6412 if not Nkind_In
(Expr
, N_Integer_Literal
, N_Real_Literal
) then
6414 ("named number for % attribute must be simple literal", N
);
6417 -- Build string literal corresponding to source literal text
6422 Store_String_Char
(Get_Char_Code
('-'));
6426 Src
:= Source_Text
(Get_Source_File_Index
(S
));
6428 while Src
(S
) /= ';' and then Src
(S
) /= ' ' loop
6429 Store_String_Char
(Get_Char_Code
(Src
(S
)));
6433 -- Now we rewrite the attribute with the string literal
6436 Make_String_Literal
(Loc
, End_String
));
6438 Set_Is_Static_Expression
(N
, True);
6442 -------------------------
6443 -- Unrestricted_Access --
6444 -------------------------
6446 -- This is a GNAT specific attribute which is like Access except that
6447 -- all scope checks and checks for aliased views are omitted. It is
6448 -- documented as being equivalent to the use of the Address attribute
6449 -- followed by an unchecked conversion to the target access type.
6451 when Attribute_Unrestricted_Access
=>
6453 -- If from source, deal with relevant restrictions
6455 if Comes_From_Source
(N
) then
6456 Check_Restriction
(No_Unchecked_Access
, N
);
6458 if Nkind
(P
) in N_Has_Entity
6459 and then Present
(Entity
(P
))
6460 and then Is_Object
(Entity
(P
))
6462 Check_Restriction
(No_Implicit_Aliasing
, N
);
6466 if Is_Entity_Name
(P
) then
6467 Set_Address_Taken
(Entity
(P
));
6470 -- It might seem reasonable to call Address_Checks here to apply the
6471 -- same set of semantic checks that we enforce for 'Address (after
6472 -- all we document Unrestricted_Access as being equivalent to the
6473 -- use of Address followed by an Unchecked_Conversion). However, if
6474 -- we do enable these checks, we get multiple failures in both the
6475 -- compiler run-time and in our regression test suite, so we leave
6476 -- out these checks for now. To be investigated further some time???
6480 -- Now complete analysis using common access processing
6482 Analyze_Access_Attribute
;
6488 when Attribute_Update
=> Update
: declare
6489 Common_Typ
: Entity_Id
;
6490 -- The common type of a multiple component update for a record
6492 Comps
: Elist_Id
:= No_Elist
;
6493 -- A list used in the resolution of a record update. It contains the
6494 -- entities of all record components processed so far.
6496 procedure Analyze_Array_Component_Update
(Assoc
: Node_Id
);
6497 -- Analyze and resolve array_component_association Assoc against the
6498 -- index of array type P_Type.
6500 procedure Analyze_Record_Component_Update
(Comp
: Node_Id
);
6501 -- Analyze and resolve record_component_association Comp against
6502 -- record type P_Type.
6504 ------------------------------------
6505 -- Analyze_Array_Component_Update --
6506 ------------------------------------
6508 procedure Analyze_Array_Component_Update
(Assoc
: Node_Id
) is
6512 Index_Typ
: Entity_Id
;
6516 -- The current association contains a sequence of indexes denoting
6517 -- an element of a multidimensional array:
6519 -- (Index_1, ..., Index_N)
6521 -- Examine each individual index and resolve it against the proper
6522 -- index type of the array.
6524 if Nkind
(First
(Choices
(Assoc
))) = N_Aggregate
then
6525 Expr
:= First
(Choices
(Assoc
));
6526 while Present
(Expr
) loop
6528 -- The use of others is illegal (SPARK RM 4.4.1(12))
6530 if Nkind
(Expr
) = N_Others_Choice
then
6532 ("others choice not allowed in attribute %", Expr
);
6534 -- Otherwise analyze and resolve all indexes
6537 Index
:= First
(Expressions
(Expr
));
6538 Index_Typ
:= First_Index
(P_Type
);
6539 while Present
(Index
) and then Present
(Index_Typ
) loop
6540 Analyze_And_Resolve
(Index
, Etype
(Index_Typ
));
6542 Next_Index
(Index_Typ
);
6545 -- Detect a case where the association either lacks an
6546 -- index or contains an extra index.
6548 if Present
(Index
) or else Present
(Index_Typ
) then
6550 ("dimension mismatch in index list", Assoc
);
6557 -- The current association denotes either a single component or a
6558 -- range of components of a one dimensional array:
6562 -- Resolve the index or its high and low bounds (if range) against
6563 -- the proper index type of the array.
6566 Index
:= First
(Choices
(Assoc
));
6567 Index_Typ
:= First_Index
(P_Type
);
6569 if Present
(Next_Index
(Index_Typ
)) then
6570 Error_Msg_N
("too few subscripts in array reference", Assoc
);
6573 while Present
(Index
) loop
6575 -- The use of others is illegal (SPARK RM 4.4.1(12))
6577 if Nkind
(Index
) = N_Others_Choice
then
6579 ("others choice not allowed in attribute %", Index
);
6581 -- The index denotes a range of elements
6583 elsif Nkind
(Index
) = N_Range
then
6584 Low
:= Low_Bound
(Index
);
6585 High
:= High_Bound
(Index
);
6587 Analyze_And_Resolve
(Low
, Etype
(Index_Typ
));
6588 Analyze_And_Resolve
(High
, Etype
(Index_Typ
));
6590 -- Add a range check to ensure that the bounds of the
6591 -- range are within the index type when this cannot be
6592 -- determined statically.
6594 if not Is_OK_Static_Expression
(Low
) then
6595 Set_Do_Range_Check
(Low
);
6598 if not Is_OK_Static_Expression
(High
) then
6599 Set_Do_Range_Check
(High
);
6602 -- Otherwise the index denotes a single element
6605 Analyze_And_Resolve
(Index
, Etype
(Index_Typ
));
6607 -- Add a range check to ensure that the index is within
6608 -- the index type when it is not possible to determine
6611 if not Is_OK_Static_Expression
(Index
) then
6612 Set_Do_Range_Check
(Index
);
6619 end Analyze_Array_Component_Update
;
6621 -------------------------------------
6622 -- Analyze_Record_Component_Update --
6623 -------------------------------------
6625 procedure Analyze_Record_Component_Update
(Comp
: Node_Id
) is
6626 Comp_Name
: constant Name_Id
:= Chars
(Comp
);
6627 Base_Typ
: Entity_Id
;
6628 Comp_Or_Discr
: Entity_Id
;
6631 -- Find the discriminant or component whose name corresponds to
6632 -- Comp. A simple character comparison is sufficient because all
6633 -- visible names within a record type are unique.
6635 Comp_Or_Discr
:= First_Entity
(P_Type
);
6636 while Present
(Comp_Or_Discr
) loop
6637 if Chars
(Comp_Or_Discr
) = Comp_Name
then
6639 -- Decorate the component reference by setting its entity
6640 -- and type for resolution purposes.
6642 Set_Entity
(Comp
, Comp_Or_Discr
);
6643 Set_Etype
(Comp
, Etype
(Comp_Or_Discr
));
6647 Comp_Or_Discr
:= Next_Entity
(Comp_Or_Discr
);
6650 -- Diagnose an illegal reference
6652 if Present
(Comp_Or_Discr
) then
6653 if Ekind
(Comp_Or_Discr
) = E_Discriminant
then
6655 ("attribute % may not modify record discriminants", Comp
);
6657 else pragma Assert
(Ekind
(Comp_Or_Discr
) = E_Component
);
6658 if Contains
(Comps
, Comp_Or_Discr
) then
6659 Error_Msg_N
("component & already updated", Comp
);
6661 -- Mark this component as processed
6664 Append_New_Elmt
(Comp_Or_Discr
, Comps
);
6668 -- The update aggregate mentions an entity that does not belong to
6672 Error_Msg_N
("& is not a component of aggregate subtype", Comp
);
6675 -- Verify the consistency of types when the current component is
6676 -- part of a miltiple component update.
6678 -- Comp_1, ..., Comp_N => <value>
6680 if Present
(Etype
(Comp
)) then
6681 Base_Typ
:= Base_Type
(Etype
(Comp
));
6683 -- Save the type of the first component reference as the
6684 -- remaning references (if any) must resolve to this type.
6686 if No
(Common_Typ
) then
6687 Common_Typ
:= Base_Typ
;
6689 elsif Base_Typ
/= Common_Typ
then
6691 ("components in choice list must have same type", Comp
);
6694 end Analyze_Record_Component_Update
;
6701 -- Start of processing for Update
6706 if not Is_Object_Reference
(P
) then
6707 Error_Attr_P
("prefix of attribute % must denote an object");
6709 elsif not Is_Array_Type
(P_Type
)
6710 and then not Is_Record_Type
(P_Type
)
6712 Error_Attr_P
("prefix of attribute % must be a record or array");
6714 elsif Is_Limited_View
(P_Type
) then
6715 Error_Attr
("prefix of attribute % cannot be limited", N
);
6717 elsif Nkind
(E1
) /= N_Aggregate
then
6718 Error_Attr
("attribute % requires component association list", N
);
6721 -- Inspect the update aggregate, looking at all the associations and
6722 -- choices. Perform the following checks:
6724 -- 1) Legality of "others" in all cases
6725 -- 2) Legality of <>
6726 -- 3) Component legality for arrays
6727 -- 4) Component legality for records
6729 -- The remaining checks are performed on the expanded attribute
6731 Assoc
:= First
(Component_Associations
(E1
));
6732 while Present
(Assoc
) loop
6734 -- The use of <> is illegal (SPARK RM 4.4.1(1))
6736 if Box_Present
(Assoc
) then
6738 ("default initialization not allowed in attribute %", Assoc
);
6740 -- Otherwise process the association
6743 Analyze
(Expression
(Assoc
));
6745 if Is_Array_Type
(P_Type
) then
6746 Analyze_Array_Component_Update
(Assoc
);
6748 elsif Is_Record_Type
(P_Type
) then
6750 -- Reset the common type used in a multiple component update
6751 -- as we are processing the contents of a new association.
6753 Common_Typ
:= Empty
;
6755 Comp
:= First
(Choices
(Assoc
));
6756 while Present
(Comp
) loop
6757 if Nkind
(Comp
) = N_Identifier
then
6758 Analyze_Record_Component_Update
(Comp
);
6760 -- The use of others is illegal (SPARK RM 4.4.1(5))
6762 elsif Nkind
(Comp
) = N_Others_Choice
then
6764 ("others choice not allowed in attribute %", Comp
);
6766 -- The name of a record component cannot appear in any
6771 ("name should be identifier or OTHERS", Comp
);
6782 -- The type of attribute 'Update is that of the prefix
6784 Set_Etype
(N
, P_Type
);
6786 Sem_Warn
.Warn_On_Suspicious_Update
(N
);
6793 when Attribute_Val
=>
6795 Check_Discrete_Type
;
6797 if Is_Boolean_Type
(P_Type
) then
6798 Error_Msg_Name_1
:= Aname
;
6799 Error_Msg_Name_2
:= Chars
(P_Type
);
6800 Check_SPARK_05_Restriction
6801 ("attribute% is not allowed for type%", P
);
6804 -- Note, we need a range check in general, but we wait for the
6805 -- Resolve call to do this, since we want to let Eval_Attribute
6806 -- have a chance to find an static illegality first.
6808 Resolve
(E1
, Any_Integer
);
6809 Set_Etype
(N
, P_Base_Type
);
6815 when Attribute_Valid
=>
6818 -- Ignore check for object if we have a 'Valid reference generated
6819 -- by the expanded code, since in some cases valid checks can occur
6820 -- on items that are names, but are not objects (e.g. attributes).
6822 if Comes_From_Source
(N
) then
6823 Check_Object_Reference
(P
);
6826 if not Is_Scalar_Type
(P_Type
) then
6827 Error_Attr_P
("object for % attribute must be of scalar type");
6830 -- If the attribute appears within the subtype's own predicate
6831 -- function, then issue a warning that this will cause infinite
6835 Pred_Func
: constant Entity_Id
:= Predicate_Function
(P_Type
);
6838 if Present
(Pred_Func
) and then Current_Scope
= Pred_Func
then
6840 ("attribute Valid requires a predicate check??", N
);
6841 Error_Msg_N
("\and will result in infinite recursion??", N
);
6845 Set_Etype
(N
, Standard_Boolean
);
6851 when Attribute_Valid_Scalars
=>
6853 Check_Object_Reference
(P
);
6854 Set_Etype
(N
, Standard_Boolean
);
6856 -- Following checks are only for source types
6858 if Comes_From_Source
(N
) then
6859 if not Scalar_Part_Present
(P_Type
) then
6861 ("??attribute % always True, no scalars to check");
6864 -- Not allowed for unchecked union type
6866 if Has_Unchecked_Union
(P_Type
) then
6868 ("attribute % not allowed for Unchecked_Union type");
6876 when Attribute_Value
=>
6877 Check_SPARK_05_Restriction_On_Attribute
;
6881 -- Case of enumeration type
6883 -- When an enumeration type appears in an attribute reference, all
6884 -- literals of the type are marked as referenced. This must only be
6885 -- done if the attribute reference appears in the current source.
6886 -- Otherwise the information on references may differ between a
6887 -- normal compilation and one that performs inlining.
6889 if Is_Enumeration_Type
(P_Type
)
6890 and then In_Extended_Main_Code_Unit
(N
)
6892 Check_Restriction
(No_Enumeration_Maps
, N
);
6894 -- Mark all enumeration literals as referenced, since the use of
6895 -- the Value attribute can implicitly reference any of the
6896 -- literals of the enumeration base type.
6899 Ent
: Entity_Id
:= First_Literal
(P_Base_Type
);
6901 while Present
(Ent
) loop
6902 Set_Referenced
(Ent
);
6908 -- Set Etype before resolving expression because expansion of
6909 -- expression may require enclosing type. Note that the type
6910 -- returned by 'Value is the base type of the prefix type.
6912 Set_Etype
(N
, P_Base_Type
);
6913 Validate_Non_Static_Attribute_Function_Call
;
6915 -- Check restriction No_Fixed_IO
6917 if Restriction_Check_Required
(No_Fixed_IO
)
6918 and then Is_Fixed_Point_Type
(P_Type
)
6920 Check_Restriction
(No_Fixed_IO
, P
);
6927 when Attribute_Value_Size
=>
6930 Check_Not_Incomplete_Type
;
6931 Set_Etype
(N
, Universal_Integer
);
6937 when Attribute_Version
=>
6940 Set_Etype
(N
, RTE
(RE_Version_String
));
6946 when Attribute_Wchar_T_Size
=>
6947 Standard_Attribute
(Interfaces_Wchar_T_Size
);
6953 when Attribute_Wide_Image
=>
6954 Check_SPARK_05_Restriction_On_Attribute
;
6956 Set_Etype
(N
, Standard_Wide_String
);
6958 Resolve
(E1
, P_Base_Type
);
6959 Validate_Non_Static_Attribute_Function_Call
;
6961 -- Check restriction No_Fixed_IO
6963 if Restriction_Check_Required
(No_Fixed_IO
)
6964 and then Is_Fixed_Point_Type
(P_Type
)
6966 Check_Restriction
(No_Fixed_IO
, P
);
6969 ---------------------
6970 -- Wide_Wide_Image --
6971 ---------------------
6973 when Attribute_Wide_Wide_Image
=>
6975 Set_Etype
(N
, Standard_Wide_Wide_String
);
6977 Resolve
(E1
, P_Base_Type
);
6978 Validate_Non_Static_Attribute_Function_Call
;
6980 -- Check restriction No_Fixed_IO
6982 if Restriction_Check_Required
(No_Fixed_IO
)
6983 and then Is_Fixed_Point_Type
(P_Type
)
6985 Check_Restriction
(No_Fixed_IO
, P
);
6992 when Attribute_Wide_Value
=>
6993 Check_SPARK_05_Restriction_On_Attribute
;
6997 -- Set Etype before resolving expression because expansion
6998 -- of expression may require enclosing type.
7000 Set_Etype
(N
, P_Type
);
7001 Validate_Non_Static_Attribute_Function_Call
;
7003 -- Check restriction No_Fixed_IO
7005 if Restriction_Check_Required
(No_Fixed_IO
)
7006 and then Is_Fixed_Point_Type
(P_Type
)
7008 Check_Restriction
(No_Fixed_IO
, P
);
7011 ---------------------
7012 -- Wide_Wide_Value --
7013 ---------------------
7015 when Attribute_Wide_Wide_Value
=>
7019 -- Set Etype before resolving expression because expansion
7020 -- of expression may require enclosing type.
7022 Set_Etype
(N
, P_Type
);
7023 Validate_Non_Static_Attribute_Function_Call
;
7025 -- Check restriction No_Fixed_IO
7027 if Restriction_Check_Required
(No_Fixed_IO
)
7028 and then Is_Fixed_Point_Type
(P_Type
)
7030 Check_Restriction
(No_Fixed_IO
, P
);
7033 ---------------------
7034 -- Wide_Wide_Width --
7035 ---------------------
7037 when Attribute_Wide_Wide_Width
=>
7040 Set_Etype
(N
, Universal_Integer
);
7046 when Attribute_Wide_Width
=>
7047 Check_SPARK_05_Restriction_On_Attribute
;
7050 Set_Etype
(N
, Universal_Integer
);
7056 when Attribute_Width
=>
7057 Check_SPARK_05_Restriction_On_Attribute
;
7060 Set_Etype
(N
, Universal_Integer
);
7066 when Attribute_Word_Size
=>
7067 Standard_Attribute
(System_Word_Size
);
7073 when Attribute_Write
=>
7075 Check_Stream_Attribute
(TSS_Stream_Write
);
7076 Set_Etype
(N
, Standard_Void_Type
);
7077 Resolve
(N
, Standard_Void_Type
);
7081 -- In SPARK certain attributes (see below) depend on Tasking_State.
7082 -- Ensure that the entity is available for gnat2why by loading it.
7083 -- See SPARK RM 9(18) for the relevant rule.
7085 if GNATprove_Mode
then
7091 when Attribute_Callable
7094 | Attribute_Terminated
7096 Unused
:= RTE
(RE_Tasking_State
);
7104 -- All errors raise Bad_Attribute, so that we get out before any further
7105 -- damage occurs when an error is detected (for example, if we check for
7106 -- one attribute expression, and the check succeeds, we want to be able
7107 -- to proceed securely assuming that an expression is in fact present.
7109 -- Note: we set the attribute analyzed in this case to prevent any
7110 -- attempt at reanalysis which could generate spurious error msgs.
7113 when Bad_Attribute
=>
7115 Set_Etype
(N
, Any_Type
);
7117 end Analyze_Attribute
;
7119 --------------------
7120 -- Eval_Attribute --
7121 --------------------
7123 procedure Eval_Attribute
(N
: Node_Id
) is
7124 Loc
: constant Source_Ptr
:= Sloc
(N
);
7125 Aname
: constant Name_Id
:= Attribute_Name
(N
);
7126 Id
: constant Attribute_Id
:= Get_Attribute_Id
(Aname
);
7127 P
: constant Node_Id
:= Prefix
(N
);
7129 C_Type
: constant Entity_Id
:= Etype
(N
);
7130 -- The type imposed by the context
7133 -- First expression, or Empty if none
7136 -- Second expression, or Empty if none
7138 P_Entity
: Entity_Id
;
7139 -- Entity denoted by prefix
7142 -- The type of the prefix
7144 P_Base_Type
: Entity_Id
;
7145 -- The base type of the prefix type
7147 P_Root_Type
: Entity_Id
;
7148 -- The root type of the prefix type
7151 -- True if the result is Static. This is set by the general processing
7152 -- to true if the prefix is static, and all expressions are static. It
7153 -- can be reset as processing continues for particular attributes. This
7154 -- flag can still be True if the reference raises a constraint error.
7155 -- Is_Static_Expression (N) is set to follow this value as it is set
7156 -- and we could always reference this, but it is convenient to have a
7157 -- simple short name to use, since it is frequently referenced.
7159 Lo_Bound
, Hi_Bound
: Node_Id
;
7160 -- Expressions for low and high bounds of type or array index referenced
7161 -- by First, Last, or Length attribute for array, set by Set_Bounds.
7164 -- Constraint error node used if we have an attribute reference has
7165 -- an argument that raises a constraint error. In this case we replace
7166 -- the attribute with a raise constraint_error node. This is important
7167 -- processing, since otherwise gigi might see an attribute which it is
7168 -- unprepared to deal with.
7170 procedure Check_Concurrent_Discriminant
(Bound
: Node_Id
);
7171 -- If Bound is a reference to a discriminant of a task or protected type
7172 -- occurring within the object's body, rewrite attribute reference into
7173 -- a reference to the corresponding discriminal. Use for the expansion
7174 -- of checks against bounds of entry family index subtypes.
7176 procedure Check_Expressions
;
7177 -- In case where the attribute is not foldable, the expressions, if
7178 -- any, of the attribute, are in a non-static context. This procedure
7179 -- performs the required additional checks.
7181 function Compile_Time_Known_Bounds
(Typ
: Entity_Id
) return Boolean;
7182 -- Determines if the given type has compile time known bounds. Note
7183 -- that we enter the case statement even in cases where the prefix
7184 -- type does NOT have known bounds, so it is important to guard any
7185 -- attempt to evaluate both bounds with a call to this function.
7187 procedure Compile_Time_Known_Attribute
(N
: Node_Id
; Val
: Uint
);
7188 -- This procedure is called when the attribute N has a non-static
7189 -- but compile time known value given by Val. It includes the
7190 -- necessary checks for out of range values.
7192 function Fore_Value
return Nat
;
7193 -- Computes the Fore value for the current attribute prefix, which is
7194 -- known to be a static fixed-point type. Used by Fore and Width.
7196 function Mantissa
return Uint
;
7197 -- Returns the Mantissa value for the prefix type
7199 procedure Set_Bounds
;
7200 -- Used for First, Last and Length attributes applied to an array or
7201 -- array subtype. Sets the variables Lo_Bound and Hi_Bound to the low
7202 -- and high bound expressions for the index referenced by the attribute
7203 -- designator (i.e. the first index if no expression is present, and the
7204 -- N'th index if the value N is present as an expression). Also used for
7205 -- First and Last of scalar types and for First_Valid and Last_Valid.
7206 -- Static is reset to False if the type or index type is not statically
7209 function Statically_Denotes_Entity
(N
: Node_Id
) return Boolean;
7210 -- Verify that the prefix of a potentially static array attribute
7211 -- satisfies the conditions of 4.9 (14).
7213 -----------------------------------
7214 -- Check_Concurrent_Discriminant --
7215 -----------------------------------
7217 procedure Check_Concurrent_Discriminant
(Bound
: Node_Id
) is
7219 -- The concurrent (task or protected) type
7222 if Nkind
(Bound
) = N_Identifier
7223 and then Ekind
(Entity
(Bound
)) = E_Discriminant
7224 and then Is_Concurrent_Record_Type
(Scope
(Entity
(Bound
)))
7226 Tsk
:= Corresponding_Concurrent_Type
(Scope
(Entity
(Bound
)));
7228 if In_Open_Scopes
(Tsk
) and then Has_Completion
(Tsk
) then
7230 -- Find discriminant of original concurrent type, and use
7231 -- its current discriminal, which is the renaming within
7232 -- the task/protected body.
7236 (Find_Body_Discriminal
(Entity
(Bound
)), Loc
));
7239 end Check_Concurrent_Discriminant
;
7241 -----------------------
7242 -- Check_Expressions --
7243 -----------------------
7245 procedure Check_Expressions
is
7249 while Present
(E
) loop
7250 Check_Non_Static_Context
(E
);
7253 end Check_Expressions
;
7255 ----------------------------------
7256 -- Compile_Time_Known_Attribute --
7257 ----------------------------------
7259 procedure Compile_Time_Known_Attribute
(N
: Node_Id
; Val
: Uint
) is
7260 T
: constant Entity_Id
:= Etype
(N
);
7263 Fold_Uint
(N
, Val
, False);
7265 -- Check that result is in bounds of the type if it is static
7267 if Is_In_Range
(N
, T
, Assume_Valid
=> False) then
7270 elsif Is_Out_Of_Range
(N
, T
) then
7271 Apply_Compile_Time_Constraint_Error
7272 (N
, "value not in range of}??", CE_Range_Check_Failed
);
7274 elsif not Range_Checks_Suppressed
(T
) then
7275 Enable_Range_Check
(N
);
7278 Set_Do_Range_Check
(N
, False);
7280 end Compile_Time_Known_Attribute
;
7282 -------------------------------
7283 -- Compile_Time_Known_Bounds --
7284 -------------------------------
7286 function Compile_Time_Known_Bounds
(Typ
: Entity_Id
) return Boolean is
7289 Compile_Time_Known_Value
(Type_Low_Bound
(Typ
))
7291 Compile_Time_Known_Value
(Type_High_Bound
(Typ
));
7292 end Compile_Time_Known_Bounds
;
7298 -- Note that the Fore calculation is based on the actual values
7299 -- of the bounds, and does not take into account possible rounding.
7301 function Fore_Value
return Nat
is
7302 Lo
: constant Uint
:= Expr_Value
(Type_Low_Bound
(P_Type
));
7303 Hi
: constant Uint
:= Expr_Value
(Type_High_Bound
(P_Type
));
7304 Small
: constant Ureal
:= Small_Value
(P_Type
);
7305 Lo_Real
: constant Ureal
:= Lo
* Small
;
7306 Hi_Real
: constant Ureal
:= Hi
* Small
;
7311 -- Bounds are given in terms of small units, so first compute
7312 -- proper values as reals.
7314 T
:= UR_Max
(abs Lo_Real
, abs Hi_Real
);
7317 -- Loop to compute proper value if more than one digit required
7319 while T
>= Ureal_10
loop
7331 -- Table of mantissa values accessed by function Computed using
7334 -- T'Mantissa = integer next above (D * log(10)/log(2)) + 1)
7336 -- where D is T'Digits (RM83 3.5.7)
7338 Mantissa_Value
: constant array (Nat
range 1 .. 40) of Nat
:= (
7380 function Mantissa
return Uint
is
7383 UI_From_Int
(Mantissa_Value
(UI_To_Int
(Digits_Value
(P_Type
))));
7390 procedure Set_Bounds
is
7396 -- For a string literal subtype, we have to construct the bounds.
7397 -- Valid Ada code never applies attributes to string literals, but
7398 -- it is convenient to allow the expander to generate attribute
7399 -- references of this type (e.g. First and Last applied to a string
7402 -- Note that the whole point of the E_String_Literal_Subtype is to
7403 -- avoid this construction of bounds, but the cases in which we
7404 -- have to materialize them are rare enough that we don't worry.
7406 -- The low bound is simply the low bound of the base type. The
7407 -- high bound is computed from the length of the string and this
7410 if Ekind
(P_Type
) = E_String_Literal_Subtype
then
7411 Ityp
:= Etype
(First_Index
(Base_Type
(P_Type
)));
7412 Lo_Bound
:= Type_Low_Bound
(Ityp
);
7415 Make_Integer_Literal
(Sloc
(P
),
7417 Expr_Value
(Lo_Bound
) + String_Literal_Length
(P_Type
) - 1);
7419 Set_Parent
(Hi_Bound
, P
);
7420 Analyze_And_Resolve
(Hi_Bound
, Etype
(Lo_Bound
));
7423 -- For non-array case, just get bounds of scalar type
7425 elsif Is_Scalar_Type
(P_Type
) then
7428 -- For a fixed-point type, we must freeze to get the attributes
7429 -- of the fixed-point type set now so we can reference them.
7431 if Is_Fixed_Point_Type
(P_Type
)
7432 and then not Is_Frozen
(Base_Type
(P_Type
))
7433 and then Compile_Time_Known_Value
(Type_Low_Bound
(P_Type
))
7434 and then Compile_Time_Known_Value
(Type_High_Bound
(P_Type
))
7436 Freeze_Fixed_Point_Type
(Base_Type
(P_Type
));
7439 -- For array case, get type of proper index
7445 Ndim
:= UI_To_Int
(Expr_Value
(E1
));
7448 Indx
:= First_Index
(P_Type
);
7449 for J
in 1 .. Ndim
- 1 loop
7453 -- If no index type, get out (some other error occurred, and
7454 -- we don't have enough information to complete the job).
7462 Ityp
:= Etype
(Indx
);
7465 -- A discrete range in an index constraint is allowed to be a
7466 -- subtype indication. This is syntactically a pain, but should
7467 -- not propagate to the entity for the corresponding index subtype.
7468 -- After checking that the subtype indication is legal, the range
7469 -- of the subtype indication should be transfered to the entity.
7470 -- The attributes for the bounds should remain the simple retrievals
7471 -- that they are now.
7473 Lo_Bound
:= Type_Low_Bound
(Ityp
);
7474 Hi_Bound
:= Type_High_Bound
(Ityp
);
7476 -- If subtype is non-static, result is definitely non-static
7478 if not Is_Static_Subtype
(Ityp
) then
7480 Set_Is_Static_Expression
(N
, False);
7482 -- Subtype is static, does it raise CE?
7484 elsif not Is_OK_Static_Subtype
(Ityp
) then
7485 Set_Raises_Constraint_Error
(N
);
7489 -------------------------------
7490 -- Statically_Denotes_Entity --
7491 -------------------------------
7493 function Statically_Denotes_Entity
(N
: Node_Id
) return Boolean is
7497 if not Is_Entity_Name
(N
) then
7504 Nkind
(Parent
(E
)) /= N_Object_Renaming_Declaration
7505 or else Statically_Denotes_Entity
(Renamed_Object
(E
));
7506 end Statically_Denotes_Entity
;
7508 -- Start of processing for Eval_Attribute
7511 -- Initialize result as non-static, will be reset if appropriate
7513 Set_Is_Static_Expression
(N
, False);
7516 -- Acquire first two expressions (at the moment, no attributes take more
7517 -- than two expressions in any case).
7519 if Present
(Expressions
(N
)) then
7520 E1
:= First
(Expressions
(N
));
7527 -- Special processing for Enabled attribute. This attribute has a very
7528 -- special prefix, and the easiest way to avoid lots of special checks
7529 -- to protect this special prefix from causing trouble is to deal with
7530 -- this attribute immediately and be done with it.
7532 if Id
= Attribute_Enabled
then
7534 -- We skip evaluation if the expander is not active. This is not just
7535 -- an optimization. It is of key importance that we not rewrite the
7536 -- attribute in a generic template, since we want to pick up the
7537 -- setting of the check in the instance, Testing Expander_Active
7538 -- might seem an easy way of doing this, but we need to account for
7539 -- ASIS needs, so check explicitly for a generic context.
7541 if not Inside_A_Generic
then
7543 C
: constant Check_Id
:= Get_Check_Id
(Chars
(P
));
7548 if C
in Predefined_Check_Id
then
7549 R
:= Scope_Suppress
.Suppress
(C
);
7551 R
:= Is_Check_Suppressed
(Empty
, C
);
7555 R
:= Is_Check_Suppressed
(Entity
(E1
), C
);
7558 Rewrite
(N
, New_Occurrence_Of
(Boolean_Literals
(not R
), Loc
));
7565 -- Attribute 'Img applied to a static enumeration value is static, and
7566 -- we will do the folding right here (things get confused if we let this
7567 -- case go through the normal circuitry).
7569 if Attribute_Name
(N
) = Name_Img
7570 and then Is_Entity_Name
(P
)
7571 and then Is_Enumeration_Type
(Etype
(Entity
(P
)))
7572 and then Is_OK_Static_Expression
(P
)
7575 Lit
: constant Entity_Id
:= Expr_Value_E
(P
);
7580 Get_Unqualified_Decoded_Name_String
(Chars
(Lit
));
7581 Set_Casing
(All_Upper_Case
);
7582 Store_String_Chars
(Name_Buffer
(1 .. Name_Len
));
7585 Rewrite
(N
, Make_String_Literal
(Loc
, Strval
=> Str
));
7586 Analyze_And_Resolve
(N
, Standard_String
);
7587 Set_Is_Static_Expression
(N
, True);
7593 -- Special processing for cases where the prefix is an object. For this
7594 -- purpose, a string literal counts as an object (attributes of string
7595 -- literals can only appear in generated code).
7597 if Is_Object_Reference
(P
) or else Nkind
(P
) = N_String_Literal
then
7599 -- For Component_Size, the prefix is an array object, and we apply
7600 -- the attribute to the type of the object. This is allowed for both
7601 -- unconstrained and constrained arrays, since the bounds have no
7602 -- influence on the value of this attribute.
7604 if Id
= Attribute_Component_Size
then
7605 P_Entity
:= Etype
(P
);
7607 -- For Enum_Rep, evaluation depends on the nature of the prefix and
7608 -- the optional argument.
7610 elsif Id
= Attribute_Enum_Rep
then
7611 if Is_Entity_Name
(P
) then
7614 Enum_Expr
: Node_Id
;
7615 -- The enumeration-type expression of interest
7620 if Ekind_In
(Entity
(P
), E_Constant
,
7621 E_Enumeration_Literal
)
7625 -- Enum_Type'Enum_Rep (E1) case
7627 elsif Is_Enumeration_Type
(Entity
(P
)) then
7630 -- Otherwise the attribute must be expanded into a
7631 -- conversion and evaluated at run time.
7638 -- We can fold if the expression is an enumeration
7639 -- literal, or if it denotes a constant whose value
7640 -- is known at compile time.
7642 if Nkind
(Enum_Expr
) in N_Has_Entity
7643 and then (Ekind
(Entity
(Enum_Expr
)) =
7644 E_Enumeration_Literal
7646 (Ekind
(Entity
(Enum_Expr
)) = E_Constant
7647 and then Nkind
(Parent
(Entity
(Enum_Expr
))) =
7648 N_Object_Declaration
7649 and then Compile_Time_Known_Value
7650 (Expression
(Parent
(Entity
(P
))))))
7652 P_Entity
:= Etype
(P
);
7659 -- Otherwise the attribute is illegal, do not attempt to perform
7660 -- any kind of folding.
7666 -- For First and Last, the prefix is an array object, and we apply
7667 -- the attribute to the type of the array, but we need a constrained
7668 -- type for this, so we use the actual subtype if available.
7670 elsif Id
= Attribute_First
or else
7671 Id
= Attribute_Last
or else
7672 Id
= Attribute_Length
7675 AS
: constant Entity_Id
:= Get_Actual_Subtype_If_Available
(P
);
7678 if Present
(AS
) and then Is_Constrained
(AS
) then
7681 -- If we have an unconstrained type we cannot fold
7689 -- For Size, give size of object if available, otherwise we
7690 -- cannot fold Size.
7692 elsif Id
= Attribute_Size
then
7693 if Is_Entity_Name
(P
)
7694 and then Known_Esize
(Entity
(P
))
7696 Compile_Time_Known_Attribute
(N
, Esize
(Entity
(P
)));
7704 -- For Alignment, give size of object if available, otherwise we
7705 -- cannot fold Alignment.
7707 elsif Id
= Attribute_Alignment
then
7708 if Is_Entity_Name
(P
)
7709 and then Known_Alignment
(Entity
(P
))
7711 Fold_Uint
(N
, Alignment
(Entity
(P
)), Static
);
7719 -- For Lock_Free, we apply the attribute to the type of the object.
7720 -- This is allowed since we have already verified that the type is a
7723 elsif Id
= Attribute_Lock_Free
then
7724 P_Entity
:= Etype
(P
);
7726 -- No other attributes for objects are folded
7733 -- Cases where P is not an object. Cannot do anything if P is not the
7734 -- name of an entity.
7736 elsif not Is_Entity_Name
(P
) then
7740 -- Otherwise get prefix entity
7743 P_Entity
:= Entity
(P
);
7746 -- If we are asked to evaluate an attribute where the prefix is a
7747 -- non-frozen generic actual type whose RM_Size is still set to zero,
7748 -- then abandon the effort.
7750 if Is_Type
(P_Entity
)
7751 and then (not Is_Frozen
(P_Entity
)
7752 and then Is_Generic_Actual_Type
(P_Entity
)
7753 and then RM_Size
(P_Entity
) = 0)
7755 -- However, the attribute Unconstrained_Array must be evaluated,
7756 -- since it is documented to be a static attribute (and can for
7757 -- example appear in a Compile_Time_Warning pragma). The frozen
7758 -- status of the type does not affect its evaluation.
7760 and then Id
/= Attribute_Unconstrained_Array
7765 -- At this stage P_Entity is the entity to which the attribute
7766 -- is to be applied. This is usually simply the entity of the
7767 -- prefix, except in some cases of attributes for objects, where
7768 -- as described above, we apply the attribute to the object type.
7770 -- Here is where we make sure that static attributes are properly
7771 -- marked as such. These are attributes whose prefix is a static
7772 -- scalar subtype, whose result is scalar, and whose arguments, if
7773 -- present, are static scalar expressions. Note that such references
7774 -- are static expressions even if they raise Constraint_Error.
7776 -- For example, Boolean'Pos (1/0 = 0) is a static expression, even
7777 -- though evaluating it raises constraint error. This means that a
7778 -- declaration like:
7780 -- X : constant := (if True then 1 else Boolean'Pos (1/0 = 0));
7782 -- is legal, since here this expression appears in a statically
7783 -- unevaluated position, so it does not actually raise an exception.
7785 if Is_Scalar_Type
(P_Entity
)
7786 and then (not Is_Generic_Type
(P_Entity
))
7787 and then Is_Static_Subtype
(P_Entity
)
7788 and then Is_Scalar_Type
(Etype
(N
))
7791 or else (Is_Static_Expression
(E1
)
7792 and then Is_Scalar_Type
(Etype
(E1
))))
7795 or else (Is_Static_Expression
(E2
)
7796 and then Is_Scalar_Type
(Etype
(E1
))))
7799 Set_Is_Static_Expression
(N
, True);
7802 -- First foldable possibility is a scalar or array type (RM 4.9(7))
7803 -- that is not generic (generic types are eliminated by RM 4.9(25)).
7804 -- Note we allow non-static non-generic types at this stage as further
7807 if Is_Type
(P_Entity
)
7808 and then (Is_Scalar_Type
(P_Entity
) or Is_Array_Type
(P_Entity
))
7809 and then (not Is_Generic_Type
(P_Entity
))
7813 -- Second foldable possibility is an array object (RM 4.9(8))
7815 elsif Ekind_In
(P_Entity
, E_Variable
, E_Constant
)
7816 and then Is_Array_Type
(Etype
(P_Entity
))
7817 and then (not Is_Generic_Type
(Etype
(P_Entity
)))
7819 P_Type
:= Etype
(P_Entity
);
7821 -- If the entity is an array constant with an unconstrained nominal
7822 -- subtype then get the type from the initial value. If the value has
7823 -- been expanded into assignments, there is no expression and the
7824 -- attribute reference remains dynamic.
7826 -- We could do better here and retrieve the type ???
7828 if Ekind
(P_Entity
) = E_Constant
7829 and then not Is_Constrained
(P_Type
)
7831 if No
(Constant_Value
(P_Entity
)) then
7834 P_Type
:= Etype
(Constant_Value
(P_Entity
));
7838 -- Definite must be folded if the prefix is not a generic type, that
7839 -- is to say if we are within an instantiation. Same processing applies
7840 -- to the GNAT attributes Atomic_Always_Lock_Free, Has_Discriminants,
7841 -- Lock_Free, Type_Class, Has_Tagged_Value, and Unconstrained_Array.
7843 elsif (Id
= Attribute_Atomic_Always_Lock_Free
or else
7844 Id
= Attribute_Definite
or else
7845 Id
= Attribute_Has_Access_Values
or else
7846 Id
= Attribute_Has_Discriminants
or else
7847 Id
= Attribute_Has_Tagged_Values
or else
7848 Id
= Attribute_Lock_Free
or else
7849 Id
= Attribute_Type_Class
or else
7850 Id
= Attribute_Unconstrained_Array
or else
7851 Id
= Attribute_Max_Alignment_For_Allocation
)
7852 and then not Is_Generic_Type
(P_Entity
)
7856 -- We can fold 'Size applied to a type if the size is known (as happens
7857 -- for a size from an attribute definition clause). At this stage, this
7858 -- can happen only for types (e.g. record types) for which the size is
7859 -- always non-static. We exclude generic types from consideration (since
7860 -- they have bogus sizes set within templates).
7862 elsif Id
= Attribute_Size
7863 and then Is_Type
(P_Entity
)
7864 and then (not Is_Generic_Type
(P_Entity
))
7865 and then Known_Static_RM_Size
(P_Entity
)
7867 Compile_Time_Known_Attribute
(N
, RM_Size
(P_Entity
));
7870 -- We can fold 'Alignment applied to a type if the alignment is known
7871 -- (as happens for an alignment from an attribute definition clause).
7872 -- At this stage, this can happen only for types (e.g. record types) for
7873 -- which the size is always non-static. We exclude generic types from
7874 -- consideration (since they have bogus sizes set within templates).
7876 elsif Id
= Attribute_Alignment
7877 and then Is_Type
(P_Entity
)
7878 and then (not Is_Generic_Type
(P_Entity
))
7879 and then Known_Alignment
(P_Entity
)
7881 Compile_Time_Known_Attribute
(N
, Alignment
(P_Entity
));
7884 -- If this is an access attribute that is known to fail accessibility
7885 -- check, rewrite accordingly.
7887 elsif Attribute_Name
(N
) = Name_Access
7888 and then Raises_Constraint_Error
(N
)
7891 Make_Raise_Program_Error
(Loc
,
7892 Reason
=> PE_Accessibility_Check_Failed
));
7893 Set_Etype
(N
, C_Type
);
7896 -- No other cases are foldable (they certainly aren't static, and at
7897 -- the moment we don't try to fold any cases other than the ones above).
7904 -- If either attribute or the prefix is Any_Type, then propagate
7905 -- Any_Type to the result and don't do anything else at all.
7907 if P_Type
= Any_Type
7908 or else (Present
(E1
) and then Etype
(E1
) = Any_Type
)
7909 or else (Present
(E2
) and then Etype
(E2
) = Any_Type
)
7911 Set_Etype
(N
, Any_Type
);
7915 -- Scalar subtype case. We have not yet enforced the static requirement
7916 -- of (RM 4.9(7)) and we don't intend to just yet, since there are cases
7917 -- of non-static attribute references (e.g. S'Digits for a non-static
7918 -- floating-point type, which we can compute at compile time).
7920 -- Note: this folding of non-static attributes is not simply a case of
7921 -- optimization. For many of the attributes affected, Gigi cannot handle
7922 -- the attribute and depends on the front end having folded them away.
7924 -- Note: although we don't require staticness at this stage, we do set
7925 -- the Static variable to record the staticness, for easy reference by
7926 -- those attributes where it matters (e.g. Succ and Pred), and also to
7927 -- be used to ensure that non-static folded things are not marked as
7928 -- being static (a check that is done right at the end).
7930 P_Root_Type
:= Root_Type
(P_Type
);
7931 P_Base_Type
:= Base_Type
(P_Type
);
7933 -- If the root type or base type is generic, then we cannot fold. This
7934 -- test is needed because subtypes of generic types are not always
7935 -- marked as being generic themselves (which seems odd???)
7937 if Is_Generic_Type
(P_Root_Type
)
7938 or else Is_Generic_Type
(P_Base_Type
)
7943 if Is_Scalar_Type
(P_Type
) then
7944 if not Is_Static_Subtype
(P_Type
) then
7946 Set_Is_Static_Expression
(N
, False);
7947 elsif not Is_OK_Static_Subtype
(P_Type
) then
7948 Set_Raises_Constraint_Error
(N
);
7951 -- Array case. We enforce the constrained requirement of (RM 4.9(7-8))
7952 -- since we can't do anything with unconstrained arrays. In addition,
7953 -- only the First, Last and Length attributes are possibly static.
7955 -- Atomic_Always_Lock_Free, Definite, Has_Access_Values,
7956 -- Has_Discriminants, Has_Tagged_Values, Lock_Free, Type_Class, and
7957 -- Unconstrained_Array are again exceptions, because they apply as well
7958 -- to unconstrained types.
7960 -- In addition Component_Size is an exception since it is possibly
7961 -- foldable, even though it is never static, and it does apply to
7962 -- unconstrained arrays. Furthermore, it is essential to fold this
7963 -- in the packed case, since otherwise the value will be incorrect.
7965 elsif Id
= Attribute_Atomic_Always_Lock_Free
or else
7966 Id
= Attribute_Definite
or else
7967 Id
= Attribute_Has_Access_Values
or else
7968 Id
= Attribute_Has_Discriminants
or else
7969 Id
= Attribute_Has_Tagged_Values
or else
7970 Id
= Attribute_Lock_Free
or else
7971 Id
= Attribute_Type_Class
or else
7972 Id
= Attribute_Unconstrained_Array
or else
7973 Id
= Attribute_Component_Size
7976 Set_Is_Static_Expression
(N
, False);
7978 elsif Id
/= Attribute_Max_Alignment_For_Allocation
then
7979 if not Is_Constrained
(P_Type
)
7980 or else (Id
/= Attribute_First
and then
7981 Id
/= Attribute_Last
and then
7982 Id
/= Attribute_Length
)
7988 -- The rules in (RM 4.9(7,8)) require a static array, but as in the
7989 -- scalar case, we hold off on enforcing staticness, since there are
7990 -- cases which we can fold at compile time even though they are not
7991 -- static (e.g. 'Length applied to a static index, even though other
7992 -- non-static indexes make the array type non-static). This is only
7993 -- an optimization, but it falls out essentially free, so why not.
7994 -- Again we compute the variable Static for easy reference later
7995 -- (note that no array attributes are static in Ada 83).
7997 -- We also need to set Static properly for subsequent legality checks
7998 -- which might otherwise accept non-static constants in contexts
7999 -- where they are not legal.
8002 Ada_Version
>= Ada_95
and then Statically_Denotes_Entity
(P
);
8003 Set_Is_Static_Expression
(N
, Static
);
8009 Nod
:= First_Index
(P_Type
);
8011 -- The expression is static if the array type is constrained
8012 -- by given bounds, and not by an initial expression. Constant
8013 -- strings are static in any case.
8015 if Root_Type
(P_Type
) /= Standard_String
then
8017 Static
and then not Is_Constr_Subt_For_U_Nominal
(P_Type
);
8018 Set_Is_Static_Expression
(N
, Static
);
8021 while Present
(Nod
) loop
8022 if not Is_Static_Subtype
(Etype
(Nod
)) then
8024 Set_Is_Static_Expression
(N
, False);
8026 elsif not Is_OK_Static_Subtype
(Etype
(Nod
)) then
8027 Set_Raises_Constraint_Error
(N
);
8029 Set_Is_Static_Expression
(N
, False);
8032 -- If however the index type is generic, or derived from
8033 -- one, attributes cannot be folded.
8035 if Is_Generic_Type
(Root_Type
(Etype
(Nod
)))
8036 and then Id
/= Attribute_Component_Size
8046 -- Check any expressions that are present. Note that these expressions,
8047 -- depending on the particular attribute type, are either part of the
8048 -- attribute designator, or they are arguments in a case where the
8049 -- attribute reference returns a function. In the latter case, the
8050 -- rule in (RM 4.9(22)) applies and in particular requires the type
8051 -- of the expressions to be scalar in order for the attribute to be
8052 -- considered to be static.
8060 while Present
(E
) loop
8062 -- If expression is not static, then the attribute reference
8063 -- result certainly cannot be static.
8065 if not Is_Static_Expression
(E
) then
8067 Set_Is_Static_Expression
(N
, False);
8070 if Raises_Constraint_Error
(E
) then
8071 Set_Raises_Constraint_Error
(N
);
8074 -- If the result is not known at compile time, or is not of
8075 -- a scalar type, then the result is definitely not static,
8076 -- so we can quit now.
8078 if not Compile_Time_Known_Value
(E
)
8079 or else not Is_Scalar_Type
(Etype
(E
))
8081 -- An odd special case, if this is a Pos attribute, this
8082 -- is where we need to apply a range check since it does
8083 -- not get done anywhere else.
8085 if Id
= Attribute_Pos
then
8086 if Is_Integer_Type
(Etype
(E
)) then
8087 Apply_Range_Check
(E
, Etype
(N
));
8094 -- If the expression raises a constraint error, then so does
8095 -- the attribute reference. We keep going in this case because
8096 -- we are still interested in whether the attribute reference
8097 -- is static even if it is not static.
8099 elsif Raises_Constraint_Error
(E
) then
8100 Set_Raises_Constraint_Error
(N
);
8106 if Raises_Constraint_Error
(Prefix
(N
)) then
8107 Set_Is_Static_Expression
(N
, False);
8112 -- Deal with the case of a static attribute reference that raises
8113 -- constraint error. The Raises_Constraint_Error flag will already
8114 -- have been set, and the Static flag shows whether the attribute
8115 -- reference is static. In any case we certainly can't fold such an
8116 -- attribute reference.
8118 -- Note that the rewriting of the attribute node with the constraint
8119 -- error node is essential in this case, because otherwise Gigi might
8120 -- blow up on one of the attributes it never expects to see.
8122 -- The constraint_error node must have the type imposed by the context,
8123 -- to avoid spurious errors in the enclosing expression.
8125 if Raises_Constraint_Error
(N
) then
8127 Make_Raise_Constraint_Error
(Sloc
(N
),
8128 Reason
=> CE_Range_Check_Failed
);
8129 Set_Etype
(CE_Node
, Etype
(N
));
8130 Set_Raises_Constraint_Error
(CE_Node
);
8132 Rewrite
(N
, Relocate_Node
(CE_Node
));
8133 Set_Raises_Constraint_Error
(N
, True);
8137 -- At this point we have a potentially foldable attribute reference.
8138 -- If Static is set, then the attribute reference definitely obeys
8139 -- the requirements in (RM 4.9(7,8,22)), and it definitely can be
8140 -- folded. If Static is not set, then the attribute may or may not
8141 -- be foldable, and the individual attribute processing routines
8142 -- test Static as required in cases where it makes a difference.
8144 -- In the case where Static is not set, we do know that all the
8145 -- expressions present are at least known at compile time (we assumed
8146 -- above that if this was not the case, then there was no hope of static
8147 -- evaluation). However, we did not require that the bounds of the
8148 -- prefix type be compile time known, let alone static). That's because
8149 -- there are many attributes that can be computed at compile time on
8150 -- non-static subtypes, even though such references are not static
8153 -- For VAX float, the root type is an IEEE type. So make sure to use the
8154 -- base type instead of the root-type for floating point attributes.
8158 -- Attributes related to Ada 2012 iterators (placeholder ???)
8160 when Attribute_Constant_Indexing
8161 | Attribute_Default_Iterator
8162 | Attribute_Implicit_Dereference
8163 | Attribute_Iterator_Element
8164 | Attribute_Iterable
8165 | Attribute_Variable_Indexing
8169 -- Internal attributes used to deal with Ada 2012 delayed aspects.
8170 -- These were already rejected by the parser. Thus they shouldn't
8173 when Internal_Attribute_Id
=>
8174 raise Program_Error
;
8180 when Attribute_Adjacent
=>
8184 (P_Base_Type
, Expr_Value_R
(E1
), Expr_Value_R
(E2
)),
8191 when Attribute_Aft
=>
8192 Fold_Uint
(N
, Aft_Value
(P_Type
), Static
);
8198 when Attribute_Alignment
=> Alignment_Block
: declare
8199 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
8202 -- Fold if alignment is set and not otherwise
8204 if Known_Alignment
(P_TypeA
) then
8205 Fold_Uint
(N
, Alignment
(P_TypeA
), Static
);
8207 end Alignment_Block
;
8209 -----------------------------
8210 -- Atomic_Always_Lock_Free --
8211 -----------------------------
8213 -- Atomic_Always_Lock_Free attribute is a Boolean, thus no need to fold
8216 when Attribute_Atomic_Always_Lock_Free
=> Atomic_Always_Lock_Free
:
8218 V
: constant Entity_Id
:=
8220 (Support_Atomic_Primitives_On_Target
8221 and then Support_Atomic_Primitives
(P_Type
));
8224 Rewrite
(N
, New_Occurrence_Of
(V
, Loc
));
8226 -- Analyze and resolve as boolean. Note that this attribute is a
8227 -- static attribute in GNAT.
8229 Analyze_And_Resolve
(N
, Standard_Boolean
);
8231 Set_Is_Static_Expression
(N
, True);
8232 end Atomic_Always_Lock_Free
;
8238 -- Bit can never be folded
8240 when Attribute_Bit
=>
8247 -- Body_version can never be static
8249 when Attribute_Body_Version
=>
8256 when Attribute_Ceiling
=>
8258 (N
, Eval_Fat
.Ceiling
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8260 --------------------
8261 -- Component_Size --
8262 --------------------
8264 when Attribute_Component_Size
=>
8265 if Known_Static_Component_Size
(P_Type
) then
8266 Fold_Uint
(N
, Component_Size
(P_Type
), Static
);
8273 when Attribute_Compose
=>
8276 Eval_Fat
.Compose
(P_Base_Type
, Expr_Value_R
(E1
), Expr_Value
(E2
)),
8283 -- Constrained is never folded for now, there may be cases that
8284 -- could be handled at compile time. To be looked at later.
8286 when Attribute_Constrained
=>
8288 -- The expander might fold it and set the static flag accordingly,
8289 -- but with expansion disabled (as in ASIS), it remains as an
8290 -- attribute reference, and this reference is not static.
8292 Set_Is_Static_Expression
(N
, False);
8299 when Attribute_Copy_Sign
=>
8303 (P_Base_Type
, Expr_Value_R
(E1
), Expr_Value_R
(E2
)),
8310 when Attribute_Definite
=>
8311 Rewrite
(N
, New_Occurrence_Of
(
8312 Boolean_Literals
(Is_Definite_Subtype
(P_Entity
)), Loc
));
8313 Analyze_And_Resolve
(N
, Standard_Boolean
);
8319 when Attribute_Delta
=>
8320 Fold_Ureal
(N
, Delta_Value
(P_Type
), True);
8326 when Attribute_Denorm
=>
8328 (N
, UI_From_Int
(Boolean'Pos (Has_Denormals
(P_Type
))), Static
);
8330 ---------------------
8331 -- Descriptor_Size --
8332 ---------------------
8334 when Attribute_Descriptor_Size
=>
8341 when Attribute_Digits
=>
8342 Fold_Uint
(N
, Digits_Value
(P_Type
), Static
);
8348 when Attribute_Emax
=>
8350 -- Ada 83 attribute is defined as (RM83 3.5.8)
8352 -- T'Emax = 4 * T'Mantissa
8354 Fold_Uint
(N
, 4 * Mantissa
, Static
);
8360 when Attribute_Enum_Rep
=> Enum_Rep
: declare
8364 -- The attribute appears in the form:
8366 -- Enum_Typ'Enum_Rep (Const)
8367 -- Enum_Typ'Enum_Rep (Enum_Lit)
8369 if Present
(E1
) then
8372 -- Otherwise the prefix denotes a constant or enumeration literal:
8375 -- Enum_Lit'Enum_Rep
8381 -- For an enumeration type with a non-standard representation use
8382 -- the Enumeration_Rep field of the proper constant. Note that this
8383 -- will not work for types Character/Wide_[Wide-]Character, since no
8384 -- real entities are created for the enumeration literals, but that
8385 -- does not matter since these two types do not have non-standard
8386 -- representations anyway.
8388 if Is_Enumeration_Type
(P_Type
)
8389 and then Has_Non_Standard_Rep
(P_Type
)
8391 Fold_Uint
(N
, Enumeration_Rep
(Expr_Value_E
(Val
)), Static
);
8393 -- For enumeration types with standard representations and all other
8394 -- cases (i.e. all integer and modular types), Enum_Rep is equivalent
8398 Fold_Uint
(N
, Expr_Value
(Val
), Static
);
8406 when Attribute_Enum_Val
=> Enum_Val
: declare
8410 -- We have something like Enum_Type'Enum_Val (23), so search for a
8411 -- corresponding value in the list of Enum_Rep values for the type.
8413 Lit
:= First_Literal
(P_Base_Type
);
8415 if Enumeration_Rep
(Lit
) = Expr_Value
(E1
) then
8416 Fold_Uint
(N
, Enumeration_Pos
(Lit
), Static
);
8423 Apply_Compile_Time_Constraint_Error
8424 (N
, "no representation value matches",
8425 CE_Range_Check_Failed
,
8426 Warn
=> not Static
);
8436 when Attribute_Epsilon
=>
8438 -- Ada 83 attribute is defined as (RM83 3.5.8)
8440 -- T'Epsilon = 2.0**(1 - T'Mantissa)
8442 Fold_Ureal
(N
, Ureal_2
** (1 - Mantissa
), True);
8448 when Attribute_Exponent
=>
8450 Eval_Fat
.Exponent
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8452 -----------------------
8453 -- Finalization_Size --
8454 -----------------------
8456 when Attribute_Finalization_Size
=>
8463 when Attribute_First
=>
8466 if Compile_Time_Known_Value
(Lo_Bound
) then
8467 if Is_Real_Type
(P_Type
) then
8468 Fold_Ureal
(N
, Expr_Value_R
(Lo_Bound
), Static
);
8470 Fold_Uint
(N
, Expr_Value
(Lo_Bound
), Static
);
8474 Check_Concurrent_Discriminant
(Lo_Bound
);
8481 when Attribute_First_Valid
=>
8482 if Has_Predicates
(P_Type
)
8483 and then Has_Static_Predicate
(P_Type
)
8486 FirstN
: constant Node_Id
:=
8487 First
(Static_Discrete_Predicate
(P_Type
));
8489 if Nkind
(FirstN
) = N_Range
then
8490 Fold_Uint
(N
, Expr_Value
(Low_Bound
(FirstN
)), Static
);
8492 Fold_Uint
(N
, Expr_Value
(FirstN
), Static
);
8498 Fold_Uint
(N
, Expr_Value
(Lo_Bound
), Static
);
8505 when Attribute_Fixed_Value
=>
8512 when Attribute_Floor
=>
8514 (N
, Eval_Fat
.Floor
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8520 when Attribute_Fore
=>
8521 if Compile_Time_Known_Bounds
(P_Type
) then
8522 Fold_Uint
(N
, UI_From_Int
(Fore_Value
), Static
);
8529 when Attribute_Fraction
=>
8531 (N
, Eval_Fat
.Fraction
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8533 -----------------------
8534 -- Has_Access_Values --
8535 -----------------------
8537 when Attribute_Has_Access_Values
=>
8538 Rewrite
(N
, New_Occurrence_Of
8539 (Boolean_Literals
(Has_Access_Values
(P_Root_Type
)), Loc
));
8540 Analyze_And_Resolve
(N
, Standard_Boolean
);
8542 -----------------------
8543 -- Has_Discriminants --
8544 -----------------------
8546 when Attribute_Has_Discriminants
=>
8547 Rewrite
(N
, New_Occurrence_Of
(
8548 Boolean_Literals
(Has_Discriminants
(P_Entity
)), Loc
));
8549 Analyze_And_Resolve
(N
, Standard_Boolean
);
8551 ----------------------
8552 -- Has_Same_Storage --
8553 ----------------------
8555 when Attribute_Has_Same_Storage
=>
8558 -----------------------
8559 -- Has_Tagged_Values --
8560 -----------------------
8562 when Attribute_Has_Tagged_Values
=>
8563 Rewrite
(N
, New_Occurrence_Of
8564 (Boolean_Literals
(Has_Tagged_Component
(P_Root_Type
)), Loc
));
8565 Analyze_And_Resolve
(N
, Standard_Boolean
);
8571 when Attribute_Identity
=>
8578 -- Image is a scalar attribute, but is never static, because it is
8579 -- not a static function (having a non-scalar argument (RM 4.9(22))
8580 -- However, we can constant-fold the image of an enumeration literal
8581 -- if names are available.
8583 when Attribute_Image
=>
8584 if Is_Entity_Name
(E1
)
8585 and then Ekind
(Entity
(E1
)) = E_Enumeration_Literal
8586 and then not Discard_Names
(First_Subtype
(Etype
(E1
)))
8587 and then not Global_Discard_Names
8590 Lit
: constant Entity_Id
:= Entity
(E1
);
8594 Get_Unqualified_Decoded_Name_String
(Chars
(Lit
));
8595 Set_Casing
(All_Upper_Case
);
8596 Store_String_Chars
(Name_Buffer
(1 .. Name_Len
));
8598 Rewrite
(N
, Make_String_Literal
(Loc
, Strval
=> Str
));
8599 Analyze_And_Resolve
(N
, Standard_String
);
8600 Set_Is_Static_Expression
(N
, False);
8608 -- We never try to fold Integer_Value (though perhaps we could???)
8610 when Attribute_Integer_Value
=>
8617 -- Invalid_Value is a scalar attribute that is never static, because
8618 -- the value is by design out of range.
8620 when Attribute_Invalid_Value
=>
8627 when Attribute_Large
=>
8629 -- For fixed-point, we use the identity:
8631 -- T'Large = (2.0**T'Mantissa - 1.0) * T'Small
8633 if Is_Fixed_Point_Type
(P_Type
) then
8635 Make_Op_Multiply
(Loc
,
8637 Make_Op_Subtract
(Loc
,
8641 Make_Real_Literal
(Loc
, Ureal_2
),
8643 Make_Attribute_Reference
(Loc
,
8645 Attribute_Name
=> Name_Mantissa
)),
8646 Right_Opnd
=> Make_Real_Literal
(Loc
, Ureal_1
)),
8649 Make_Real_Literal
(Loc
, Small_Value
(Entity
(P
)))));
8651 Analyze_And_Resolve
(N
, C_Type
);
8653 -- Floating-point (Ada 83 compatibility)
8656 -- Ada 83 attribute is defined as (RM83 3.5.8)
8658 -- T'Large = 2.0**T'Emax * (1.0 - 2.0**(-T'Mantissa))
8662 -- T'Emax = 4 * T'Mantissa
8666 Ureal_2
** (4 * Mantissa
) * (Ureal_1
- Ureal_2
** (-Mantissa
)),
8674 when Attribute_Lock_Free
=> Lock_Free
: declare
8675 V
: constant Entity_Id
:= Boolean_Literals
(Uses_Lock_Free
(P_Type
));
8678 Rewrite
(N
, New_Occurrence_Of
(V
, Loc
));
8680 -- Analyze and resolve as boolean. Note that this attribute is a
8681 -- static attribute in GNAT.
8683 Analyze_And_Resolve
(N
, Standard_Boolean
);
8685 Set_Is_Static_Expression
(N
, True);
8692 when Attribute_Last
=>
8695 if Compile_Time_Known_Value
(Hi_Bound
) then
8696 if Is_Real_Type
(P_Type
) then
8697 Fold_Ureal
(N
, Expr_Value_R
(Hi_Bound
), Static
);
8699 Fold_Uint
(N
, Expr_Value
(Hi_Bound
), Static
);
8703 Check_Concurrent_Discriminant
(Hi_Bound
);
8710 when Attribute_Last_Valid
=>
8711 if Has_Predicates
(P_Type
)
8712 and then Has_Static_Predicate
(P_Type
)
8715 LastN
: constant Node_Id
:=
8716 Last
(Static_Discrete_Predicate
(P_Type
));
8718 if Nkind
(LastN
) = N_Range
then
8719 Fold_Uint
(N
, Expr_Value
(High_Bound
(LastN
)), Static
);
8721 Fold_Uint
(N
, Expr_Value
(LastN
), Static
);
8727 Fold_Uint
(N
, Expr_Value
(Hi_Bound
), Static
);
8734 when Attribute_Leading_Part
=>
8737 Eval_Fat
.Leading_Part
8738 (P_Base_Type
, Expr_Value_R
(E1
), Expr_Value
(E2
)),
8745 when Attribute_Length
=> Length
: declare
8749 -- If any index type is a formal type, or derived from one, the
8750 -- bounds are not static. Treating them as static can produce
8751 -- spurious warnings or improper constant folding.
8753 Ind
:= First_Index
(P_Type
);
8754 while Present
(Ind
) loop
8755 if Is_Generic_Type
(Root_Type
(Etype
(Ind
))) then
8764 -- For two compile time values, we can compute length
8766 if Compile_Time_Known_Value
(Lo_Bound
)
8767 and then Compile_Time_Known_Value
(Hi_Bound
)
8770 UI_Max
(0, 1 + (Expr_Value
(Hi_Bound
) - Expr_Value
(Lo_Bound
))),
8774 -- One more case is where Hi_Bound and Lo_Bound are compile-time
8775 -- comparable, and we can figure out the difference between them.
8778 Diff
: aliased Uint
;
8782 Compile_Time_Compare
8783 (Lo_Bound
, Hi_Bound
, Diff
'Access, Assume_Valid
=> False)
8786 Fold_Uint
(N
, Uint_1
, Static
);
8789 Fold_Uint
(N
, Uint_0
, Static
);
8792 if Diff
/= No_Uint
then
8793 Fold_Uint
(N
, Diff
+ 1, Static
);
8806 -- Loop_Entry acts as an alias of a constant initialized to the prefix
8807 -- of the said attribute at the point of entry into the related loop. As
8808 -- such, the attribute reference does not need to be evaluated because
8809 -- the prefix is the one that is evaluted.
8811 when Attribute_Loop_Entry
=>
8818 when Attribute_Machine
=>
8822 (P_Base_Type
, Expr_Value_R
(E1
), Eval_Fat
.Round
, N
),
8829 when Attribute_Machine_Emax
=>
8830 Fold_Uint
(N
, Machine_Emax_Value
(P_Type
), Static
);
8836 when Attribute_Machine_Emin
=>
8837 Fold_Uint
(N
, Machine_Emin_Value
(P_Type
), Static
);
8839 ----------------------
8840 -- Machine_Mantissa --
8841 ----------------------
8843 when Attribute_Machine_Mantissa
=>
8844 Fold_Uint
(N
, Machine_Mantissa_Value
(P_Type
), Static
);
8846 -----------------------
8847 -- Machine_Overflows --
8848 -----------------------
8850 when Attribute_Machine_Overflows
=>
8852 -- Always true for fixed-point
8854 if Is_Fixed_Point_Type
(P_Type
) then
8855 Fold_Uint
(N
, True_Value
, Static
);
8857 -- Floating point case
8861 UI_From_Int
(Boolean'Pos (Machine_Overflows_On_Target
)),
8869 when Attribute_Machine_Radix
=>
8870 if Is_Fixed_Point_Type
(P_Type
) then
8871 if Is_Decimal_Fixed_Point_Type
(P_Type
)
8872 and then Machine_Radix_10
(P_Type
)
8874 Fold_Uint
(N
, Uint_10
, Static
);
8876 Fold_Uint
(N
, Uint_2
, Static
);
8879 -- All floating-point type always have radix 2
8882 Fold_Uint
(N
, Uint_2
, Static
);
8885 ----------------------
8886 -- Machine_Rounding --
8887 ----------------------
8889 -- Note: for the folding case, it is fine to treat Machine_Rounding
8890 -- exactly the same way as Rounding, since this is one of the allowed
8891 -- behaviors, and performance is not an issue here. It might be a bit
8892 -- better to give the same result as it would give at run time, even
8893 -- though the non-determinism is certainly permitted.
8895 when Attribute_Machine_Rounding
=>
8897 (N
, Eval_Fat
.Rounding
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8899 --------------------
8900 -- Machine_Rounds --
8901 --------------------
8903 when Attribute_Machine_Rounds
=>
8905 -- Always False for fixed-point
8907 if Is_Fixed_Point_Type
(P_Type
) then
8908 Fold_Uint
(N
, False_Value
, Static
);
8910 -- Else yield proper floating-point result
8914 (N
, UI_From_Int
(Boolean'Pos (Machine_Rounds_On_Target
)),
8922 -- Note: Machine_Size is identical to Object_Size
8924 when Attribute_Machine_Size
=> Machine_Size
: declare
8925 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
8928 if Known_Esize
(P_TypeA
) then
8929 Fold_Uint
(N
, Esize
(P_TypeA
), Static
);
8937 when Attribute_Mantissa
=>
8939 -- Fixed-point mantissa
8941 if Is_Fixed_Point_Type
(P_Type
) then
8943 -- Compile time foldable case
8945 if Compile_Time_Known_Value
(Type_Low_Bound
(P_Type
))
8947 Compile_Time_Known_Value
(Type_High_Bound
(P_Type
))
8949 -- The calculation of the obsolete Ada 83 attribute Mantissa
8950 -- is annoying, because of AI00143, quoted here:
8952 -- !question 84-01-10
8954 -- Consider the model numbers for F:
8956 -- type F is delta 1.0 range -7.0 .. 8.0;
8958 -- The wording requires that F'MANTISSA be the SMALLEST
8959 -- integer number for which each bound of the specified
8960 -- range is either a model number or lies at most small
8961 -- distant from a model number. This means F'MANTISSA
8962 -- is required to be 3 since the range -7.0 .. 7.0 fits
8963 -- in 3 signed bits, and 8 is "at most" 1.0 from a model
8964 -- number, namely, 7. Is this analysis correct? Note that
8965 -- this implies the upper bound of the range is not
8966 -- represented as a model number.
8968 -- !response 84-03-17
8970 -- The analysis is correct. The upper and lower bounds for
8971 -- a fixed point type can lie outside the range of model
8982 LBound
:= Expr_Value_R
(Type_Low_Bound
(P_Type
));
8983 UBound
:= Expr_Value_R
(Type_High_Bound
(P_Type
));
8984 Bound
:= UR_Max
(UR_Abs
(LBound
), UR_Abs
(UBound
));
8985 Max_Man
:= UR_Trunc
(Bound
/ Small_Value
(P_Type
));
8987 -- If the Bound is exactly a model number, i.e. a multiple
8988 -- of Small, then we back it off by one to get the integer
8989 -- value that must be representable.
8991 if Small_Value
(P_Type
) * Max_Man
= Bound
then
8992 Max_Man
:= Max_Man
- 1;
8995 -- Now find corresponding size = Mantissa value
8998 while 2 ** Siz
< Max_Man
loop
9002 Fold_Uint
(N
, Siz
, Static
);
9006 -- The case of dynamic bounds cannot be evaluated at compile
9007 -- time. Instead we use a runtime routine (see Exp_Attr).
9012 -- Floating-point Mantissa
9015 Fold_Uint
(N
, Mantissa
, Static
);
9022 when Attribute_Max
=>
9023 if Is_Real_Type
(P_Type
) then
9025 (N
, UR_Max
(Expr_Value_R
(E1
), Expr_Value_R
(E2
)), Static
);
9027 Fold_Uint
(N
, UI_Max
(Expr_Value
(E1
), Expr_Value
(E2
)), Static
);
9030 ----------------------------------
9031 -- Max_Alignment_For_Allocation --
9032 ----------------------------------
9034 -- Max_Alignment_For_Allocation is usually the Alignment. However,
9035 -- arrays are allocated with dope, so we need to take into account both
9036 -- the alignment of the array, which comes from the component alignment,
9037 -- and the alignment of the dope. Also, if the alignment is unknown, we
9038 -- use the max (it's OK to be pessimistic).
9040 when Attribute_Max_Alignment_For_Allocation
=> Max_Align
: declare
9041 A
: Uint
:= UI_From_Int
(Ttypes
.Maximum_Alignment
);
9043 if Known_Alignment
(P_Type
)
9044 and then (not Is_Array_Type
(P_Type
) or else Alignment
(P_Type
) > A
)
9046 A
:= Alignment
(P_Type
);
9049 Fold_Uint
(N
, A
, Static
);
9052 ----------------------------------
9053 -- Max_Size_In_Storage_Elements --
9054 ----------------------------------
9056 -- Max_Size_In_Storage_Elements is simply the Size rounded up to a
9057 -- Storage_Unit boundary. We can fold any cases for which the size
9058 -- is known by the front end.
9060 when Attribute_Max_Size_In_Storage_Elements
=>
9061 if Known_Esize
(P_Type
) then
9063 (Esize
(P_Type
) + System_Storage_Unit
- 1) /
9064 System_Storage_Unit
,
9068 --------------------
9069 -- Mechanism_Code --
9070 --------------------
9072 when Attribute_Mechanism_Code
=> Mechanism_Code
: declare
9074 Mech
: Mechanism_Type
;
9079 Mech
:= Mechanism
(P_Entity
);
9082 Val
:= UI_To_Int
(Expr_Value
(E1
));
9084 Formal
:= First_Formal
(P_Entity
);
9085 for J
in 1 .. Val
- 1 loop
9086 Next_Formal
(Formal
);
9089 Mech
:= Mechanism
(Formal
);
9093 Fold_Uint
(N
, UI_From_Int
(Int
(-Mech
)), Static
);
9101 when Attribute_Min
=>
9102 if Is_Real_Type
(P_Type
) then
9104 (N
, UR_Min
(Expr_Value_R
(E1
), Expr_Value_R
(E2
)), Static
);
9107 (N
, UI_Min
(Expr_Value
(E1
), Expr_Value
(E2
)), Static
);
9114 when Attribute_Mod
=>
9116 (N
, UI_Mod
(Expr_Value
(E1
), Modulus
(P_Base_Type
)), Static
);
9122 when Attribute_Model
=>
9124 (N
, Eval_Fat
.Model
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
9130 when Attribute_Model_Emin
=>
9131 Fold_Uint
(N
, Model_Emin_Value
(P_Base_Type
), Static
);
9137 when Attribute_Model_Epsilon
=>
9138 Fold_Ureal
(N
, Model_Epsilon_Value
(P_Base_Type
), Static
);
9140 --------------------
9141 -- Model_Mantissa --
9142 --------------------
9144 when Attribute_Model_Mantissa
=>
9145 Fold_Uint
(N
, Model_Mantissa_Value
(P_Base_Type
), Static
);
9151 when Attribute_Model_Small
=>
9152 Fold_Ureal
(N
, Model_Small_Value
(P_Base_Type
), Static
);
9158 when Attribute_Modulus
=>
9159 Fold_Uint
(N
, Modulus
(P_Type
), Static
);
9161 --------------------
9162 -- Null_Parameter --
9163 --------------------
9165 -- Cannot fold, we know the value sort of, but the whole point is
9166 -- that there is no way to talk about this imaginary value except
9167 -- by using the attribute, so we leave it the way it is.
9169 when Attribute_Null_Parameter
=>
9176 -- The Object_Size attribute for a type returns the Esize of the
9177 -- type and can be folded if this value is known.
9179 when Attribute_Object_Size
=> Object_Size
: declare
9180 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
9183 if Known_Esize
(P_TypeA
) then
9184 Fold_Uint
(N
, Esize
(P_TypeA
), Static
);
9188 ----------------------
9189 -- Overlaps_Storage --
9190 ----------------------
9192 when Attribute_Overlaps_Storage
=>
9195 -------------------------
9196 -- Passed_By_Reference --
9197 -------------------------
9199 -- Scalar types are never passed by reference
9201 when Attribute_Passed_By_Reference
=>
9202 Fold_Uint
(N
, False_Value
, Static
);
9208 when Attribute_Pos
=>
9209 Fold_Uint
(N
, Expr_Value
(E1
), Static
);
9215 when Attribute_Pred
=>
9217 -- Floating-point case
9219 if Is_Floating_Point_Type
(P_Type
) then
9221 (N
, Eval_Fat
.Pred
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
9225 elsif Is_Fixed_Point_Type
(P_Type
) then
9227 (N
, Expr_Value_R
(E1
) - Small_Value
(P_Type
), True);
9229 -- Modular integer case (wraps)
9231 elsif Is_Modular_Integer_Type
(P_Type
) then
9232 Fold_Uint
(N
, (Expr_Value
(E1
) - 1) mod Modulus
(P_Type
), Static
);
9234 -- Other scalar cases
9237 pragma Assert
(Is_Scalar_Type
(P_Type
));
9239 if Is_Enumeration_Type
(P_Type
)
9240 and then Expr_Value
(E1
) =
9241 Expr_Value
(Type_Low_Bound
(P_Base_Type
))
9243 Apply_Compile_Time_Constraint_Error
9244 (N
, "Pred of `&''First`",
9245 CE_Overflow_Check_Failed
,
9247 Warn
=> not Static
);
9253 Fold_Uint
(N
, Expr_Value
(E1
) - 1, Static
);
9260 -- No processing required, because by this stage, Range has been
9261 -- replaced by First .. Last, so this branch can never be taken.
9263 when Attribute_Range
=>
9264 raise Program_Error
;
9270 when Attribute_Range_Length
=> Range_Length
: declare
9271 Diff
: aliased Uint
;
9276 -- Can fold if both bounds are compile time known
9278 if Compile_Time_Known_Value
(Hi_Bound
)
9279 and then Compile_Time_Known_Value
(Lo_Bound
)
9283 (0, Expr_Value
(Hi_Bound
) - Expr_Value
(Lo_Bound
) + 1),
9287 -- One more case is where Hi_Bound and Lo_Bound are compile-time
9288 -- comparable, and we can figure out the difference between them.
9290 case Compile_Time_Compare
9291 (Lo_Bound
, Hi_Bound
, Diff
'Access, Assume_Valid
=> False)
9294 Fold_Uint
(N
, Uint_1
, Static
);
9297 Fold_Uint
(N
, Uint_0
, Static
);
9300 if Diff
/= No_Uint
then
9301 Fold_Uint
(N
, Diff
+ 1, Static
);
9313 when Attribute_Ref
=>
9314 Fold_Uint
(N
, Expr_Value
(E1
), Static
);
9320 when Attribute_Remainder
=> Remainder
: declare
9321 X
: constant Ureal
:= Expr_Value_R
(E1
);
9322 Y
: constant Ureal
:= Expr_Value_R
(E2
);
9325 if UR_Is_Zero
(Y
) then
9326 Apply_Compile_Time_Constraint_Error
9327 (N
, "division by zero in Remainder",
9328 CE_Overflow_Check_Failed
,
9329 Warn
=> not Static
);
9335 Fold_Ureal
(N
, Eval_Fat
.Remainder
(P_Base_Type
, X
, Y
), Static
);
9342 when Attribute_Restriction_Set
=>
9343 Rewrite
(N
, New_Occurrence_Of
(Standard_False
, Loc
));
9344 Set_Is_Static_Expression
(N
);
9350 when Attribute_Round
=> Round
: declare
9355 -- First we get the (exact result) in units of small
9357 Sr
:= Expr_Value_R
(E1
) / Small_Value
(C_Type
);
9359 -- Now round that exactly to an integer
9361 Si
:= UR_To_Uint
(Sr
);
9363 -- Finally the result is obtained by converting back to real
9365 Fold_Ureal
(N
, Si
* Small_Value
(C_Type
), Static
);
9372 when Attribute_Rounding
=>
9374 (N
, Eval_Fat
.Rounding
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
9380 when Attribute_Safe_Emax
=>
9381 Fold_Uint
(N
, Safe_Emax_Value
(P_Type
), Static
);
9387 when Attribute_Safe_First
=>
9388 Fold_Ureal
(N
, Safe_First_Value
(P_Type
), Static
);
9394 when Attribute_Safe_Large
=>
9395 if Is_Fixed_Point_Type
(P_Type
) then
9397 (N
, Expr_Value_R
(Type_High_Bound
(P_Base_Type
)), Static
);
9399 Fold_Ureal
(N
, Safe_Last_Value
(P_Type
), Static
);
9406 when Attribute_Safe_Last
=>
9407 Fold_Ureal
(N
, Safe_Last_Value
(P_Type
), Static
);
9413 when Attribute_Safe_Small
=>
9415 -- In Ada 95, the old Ada 83 attribute Safe_Small is redundant
9416 -- for fixed-point, since is the same as Small, but we implement
9417 -- it for backwards compatibility.
9419 if Is_Fixed_Point_Type
(P_Type
) then
9420 Fold_Ureal
(N
, Small_Value
(P_Type
), Static
);
9422 -- Ada 83 Safe_Small for floating-point cases
9425 Fold_Ureal
(N
, Model_Small_Value
(P_Type
), Static
);
9432 when Attribute_Scale
=>
9433 Fold_Uint
(N
, Scale_Value
(P_Type
), Static
);
9439 when Attribute_Scaling
=>
9443 (P_Base_Type
, Expr_Value_R
(E1
), Expr_Value
(E2
)),
9450 when Attribute_Signed_Zeros
=>
9452 (N
, UI_From_Int
(Boolean'Pos (Has_Signed_Zeros
(P_Type
))), Static
);
9458 -- Size attribute returns the RM size. All scalar types can be folded,
9459 -- as well as any types for which the size is known by the front end,
9460 -- including any type for which a size attribute is specified. This is
9461 -- one of the places where it is annoying that a size of zero means two
9462 -- things (zero size for scalars, unspecified size for non-scalars).
9465 | Attribute_VADS_Size
9468 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
9471 if Is_Scalar_Type
(P_TypeA
)
9472 or else RM_Size
(P_TypeA
) /= Uint_0
9476 if Id
= Attribute_VADS_Size
or else Use_VADS_Size
then
9478 S
: constant Node_Id
:= Size_Clause
(P_TypeA
);
9481 -- If a size clause applies, then use the size from it.
9482 -- This is one of the rare cases where we can use the
9483 -- Size_Clause field for a subtype when Has_Size_Clause
9484 -- is False. Consider:
9486 -- type x is range 1 .. 64;
9487 -- for x'size use 12;
9488 -- subtype y is x range 0 .. 3;
9490 -- Here y has a size clause inherited from x, but
9491 -- normally it does not apply, and y'size is 2. However,
9492 -- y'VADS_Size is indeed 12 and not 2.
9495 and then Is_OK_Static_Expression
(Expression
(S
))
9497 Fold_Uint
(N
, Expr_Value
(Expression
(S
)), Static
);
9499 -- If no size is specified, then we simply use the object
9500 -- size in the VADS_Size case (e.g. Natural'Size is equal
9501 -- to Integer'Size, not one less).
9504 Fold_Uint
(N
, Esize
(P_TypeA
), Static
);
9508 -- Normal case (Size) in which case we want the RM_Size
9511 Fold_Uint
(N
, RM_Size
(P_TypeA
), Static
);
9520 when Attribute_Small
=>
9522 -- The floating-point case is present only for Ada 83 compatibility.
9523 -- Note that strictly this is an illegal addition, since we are
9524 -- extending an Ada 95 defined attribute, but we anticipate an
9525 -- ARG ruling that will permit this.
9527 if Is_Floating_Point_Type
(P_Type
) then
9529 -- Ada 83 attribute is defined as (RM83 3.5.8)
9531 -- T'Small = 2.0**(-T'Emax - 1)
9535 -- T'Emax = 4 * T'Mantissa
9537 Fold_Ureal
(N
, Ureal_2
** ((-(4 * Mantissa
)) - 1), Static
);
9539 -- Normal Ada 95 fixed-point case
9542 Fold_Ureal
(N
, Small_Value
(P_Type
), True);
9549 when Attribute_Stream_Size
=>
9556 when Attribute_Succ
=>
9557 -- Floating-point case
9559 if Is_Floating_Point_Type
(P_Type
) then
9561 (N
, Eval_Fat
.Succ
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
9565 elsif Is_Fixed_Point_Type
(P_Type
) then
9566 Fold_Ureal
(N
, Expr_Value_R
(E1
) + Small_Value
(P_Type
), Static
);
9568 -- Modular integer case (wraps)
9570 elsif Is_Modular_Integer_Type
(P_Type
) then
9571 Fold_Uint
(N
, (Expr_Value
(E1
) + 1) mod Modulus
(P_Type
), Static
);
9573 -- Other scalar cases
9576 pragma Assert
(Is_Scalar_Type
(P_Type
));
9578 if Is_Enumeration_Type
(P_Type
)
9579 and then Expr_Value
(E1
) =
9580 Expr_Value
(Type_High_Bound
(P_Base_Type
))
9582 Apply_Compile_Time_Constraint_Error
9583 (N
, "Succ of `&''Last`",
9584 CE_Overflow_Check_Failed
,
9586 Warn
=> not Static
);
9591 Fold_Uint
(N
, Expr_Value
(E1
) + 1, Static
);
9599 when Attribute_Truncation
=>
9602 Eval_Fat
.Truncation
(P_Base_Type
, Expr_Value_R
(E1
)),
9609 when Attribute_Type_Class
=> Type_Class
: declare
9610 Typ
: constant Entity_Id
:= Underlying_Type
(P_Base_Type
);
9614 if Is_Descendant_Of_Address
(Typ
) then
9615 Id
:= RE_Type_Class_Address
;
9617 elsif Is_Enumeration_Type
(Typ
) then
9618 Id
:= RE_Type_Class_Enumeration
;
9620 elsif Is_Integer_Type
(Typ
) then
9621 Id
:= RE_Type_Class_Integer
;
9623 elsif Is_Fixed_Point_Type
(Typ
) then
9624 Id
:= RE_Type_Class_Fixed_Point
;
9626 elsif Is_Floating_Point_Type
(Typ
) then
9627 Id
:= RE_Type_Class_Floating_Point
;
9629 elsif Is_Array_Type
(Typ
) then
9630 Id
:= RE_Type_Class_Array
;
9632 elsif Is_Record_Type
(Typ
) then
9633 Id
:= RE_Type_Class_Record
;
9635 elsif Is_Access_Type
(Typ
) then
9636 Id
:= RE_Type_Class_Access
;
9638 elsif Is_Enumeration_Type
(Typ
) then
9639 Id
:= RE_Type_Class_Enumeration
;
9641 elsif Is_Task_Type
(Typ
) then
9642 Id
:= RE_Type_Class_Task
;
9644 -- We treat protected types like task types. It would make more
9645 -- sense to have another enumeration value, but after all the
9646 -- whole point of this feature is to be exactly DEC compatible,
9647 -- and changing the type Type_Class would not meet this requirement.
9649 elsif Is_Protected_Type
(Typ
) then
9650 Id
:= RE_Type_Class_Task
;
9652 -- Not clear if there are any other possibilities, but if there
9653 -- are, then we will treat them as the address case.
9656 Id
:= RE_Type_Class_Address
;
9659 Rewrite
(N
, New_Occurrence_Of
(RTE
(Id
), Loc
));
9662 -----------------------
9663 -- Unbiased_Rounding --
9664 -----------------------
9666 when Attribute_Unbiased_Rounding
=>
9669 Eval_Fat
.Unbiased_Rounding
(P_Base_Type
, Expr_Value_R
(E1
)),
9672 -------------------------
9673 -- Unconstrained_Array --
9674 -------------------------
9676 when Attribute_Unconstrained_Array
=> Unconstrained_Array
: declare
9677 Typ
: constant Entity_Id
:= Underlying_Type
(P_Type
);
9680 Rewrite
(N
, New_Occurrence_Of
(
9682 Is_Array_Type
(P_Type
)
9683 and then not Is_Constrained
(Typ
)), Loc
));
9685 -- Analyze and resolve as boolean, note that this attribute is
9686 -- a static attribute in GNAT.
9688 Analyze_And_Resolve
(N
, Standard_Boolean
);
9690 Set_Is_Static_Expression
(N
, True);
9691 end Unconstrained_Array
;
9693 -- Attribute Update is never static
9695 when Attribute_Update
=>
9702 -- Processing is shared with Size
9708 when Attribute_Val
=>
9709 if Expr_Value
(E1
) < Expr_Value
(Type_Low_Bound
(P_Base_Type
))
9711 Expr_Value
(E1
) > Expr_Value
(Type_High_Bound
(P_Base_Type
))
9713 Apply_Compile_Time_Constraint_Error
9714 (N
, "Val expression out of range",
9715 CE_Range_Check_Failed
,
9716 Warn
=> not Static
);
9722 Fold_Uint
(N
, Expr_Value
(E1
), Static
);
9729 -- The Value_Size attribute for a type returns the RM size of the type.
9730 -- This an always be folded for scalar types, and can also be folded for
9731 -- non-scalar types if the size is set. This is one of the places where
9732 -- it is annoying that a size of zero means two things!
9734 when Attribute_Value_Size
=> Value_Size
: declare
9735 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
9738 if Is_Scalar_Type
(P_TypeA
) or else RM_Size
(P_TypeA
) /= Uint_0
then
9739 Fold_Uint
(N
, RM_Size
(P_TypeA
), Static
);
9747 -- Version can never be static
9749 when Attribute_Version
=>
9756 -- Wide_Image is a scalar attribute, but is never static, because it
9757 -- is not a static function (having a non-scalar argument (RM 4.9(22))
9759 when Attribute_Wide_Image
=>
9762 ---------------------
9763 -- Wide_Wide_Image --
9764 ---------------------
9766 -- Wide_Wide_Image is a scalar attribute but is never static, because it
9767 -- is not a static function (having a non-scalar argument (RM 4.9(22)).
9769 when Attribute_Wide_Wide_Image
=>
9772 ---------------------
9773 -- Wide_Wide_Width --
9774 ---------------------
9776 -- Processing for Wide_Wide_Width is combined with Width
9782 -- Processing for Wide_Width is combined with Width
9788 -- This processing also handles the case of Wide_[Wide_]Width
9790 when Attribute_Width
9791 | Attribute_Wide_Width
9792 | Attribute_Wide_Wide_Width
9794 if Compile_Time_Known_Bounds
(P_Type
) then
9796 -- Floating-point types
9798 if Is_Floating_Point_Type
(P_Type
) then
9800 -- Width is zero for a null range (RM 3.5 (38))
9802 if Expr_Value_R
(Type_High_Bound
(P_Type
)) <
9803 Expr_Value_R
(Type_Low_Bound
(P_Type
))
9805 Fold_Uint
(N
, Uint_0
, Static
);
9808 -- For floating-point, we have +N.dddE+nnn where length
9809 -- of ddd is determined by type'Digits - 1, but is one
9810 -- if Digits is one (RM 3.5 (33)).
9812 -- nnn is set to 2 for Short_Float and Float (32 bit
9813 -- floats), and 3 for Long_Float and Long_Long_Float.
9814 -- For machines where Long_Long_Float is the IEEE
9815 -- extended precision type, the exponent takes 4 digits.
9819 Int
'Max (2, UI_To_Int
(Digits_Value
(P_Type
)));
9822 if Esize
(P_Type
) <= 32 then
9824 elsif Esize
(P_Type
) = 64 then
9830 Fold_Uint
(N
, UI_From_Int
(Len
), Static
);
9834 -- Fixed-point types
9836 elsif Is_Fixed_Point_Type
(P_Type
) then
9838 -- Width is zero for a null range (RM 3.5 (38))
9840 if Expr_Value
(Type_High_Bound
(P_Type
)) <
9841 Expr_Value
(Type_Low_Bound
(P_Type
))
9843 Fold_Uint
(N
, Uint_0
, Static
);
9845 -- The non-null case depends on the specific real type
9848 -- For fixed-point type width is Fore + 1 + Aft (RM 3.5(34))
9851 (N
, UI_From_Int
(Fore_Value
+ 1) + Aft_Value
(P_Type
),
9859 R
: constant Entity_Id
:= Root_Type
(P_Type
);
9860 Lo
: constant Uint
:= Expr_Value
(Type_Low_Bound
(P_Type
));
9861 Hi
: constant Uint
:= Expr_Value
(Type_High_Bound
(P_Type
));
9874 -- Width for types derived from Standard.Character
9875 -- and Standard.Wide_[Wide_]Character.
9877 elsif Is_Standard_Character_Type
(P_Type
) then
9880 -- Set W larger if needed
9882 for J
in UI_To_Int
(Lo
) .. UI_To_Int
(Hi
) loop
9884 -- All wide characters look like Hex_hhhhhhhh
9888 -- No need to compute this more than once
9893 C
:= Character'Val (J
);
9895 -- Test for all cases where Character'Image
9896 -- yields an image that is longer than three
9897 -- characters. First the cases of Reserved_xxx
9898 -- names (length = 12).
9976 | No_Break_Space
.. LC_Y_Diaeresis
9978 -- Special case of soft hyphen in Ada 2005
9980 if C
= Character'Val (16#AD#
)
9981 and then Ada_Version
>= Ada_2005
9989 W
:= Int
'Max (W
, Wt
);
9993 -- Width for types derived from Standard.Boolean
9995 elsif R
= Standard_Boolean
then
10002 -- Width for integer types
10004 elsif Is_Integer_Type
(P_Type
) then
10005 T
:= UI_Max
(abs Lo
, abs Hi
);
10013 -- User declared enum type with discard names
10015 elsif Discard_Names
(R
) then
10017 -- If range is null, result is zero, that has already
10018 -- been dealt with, so what we need is the power of ten
10019 -- that accomodates the Pos of the largest value, which
10020 -- is the high bound of the range + one for the space.
10029 -- Only remaining possibility is user declared enum type
10030 -- with normal case of Discard_Names not active.
10033 pragma Assert
(Is_Enumeration_Type
(P_Type
));
10036 L
:= First_Literal
(P_Type
);
10037 while Present
(L
) loop
10039 -- Only pay attention to in range characters
10041 if Lo
<= Enumeration_Pos
(L
)
10042 and then Enumeration_Pos
(L
) <= Hi
10044 -- For Width case, use decoded name
10046 if Id
= Attribute_Width
then
10047 Get_Decoded_Name_String
(Chars
(L
));
10048 Wt
:= Nat
(Name_Len
);
10050 -- For Wide_[Wide_]Width, use encoded name, and
10051 -- then adjust for the encoding.
10054 Get_Name_String
(Chars
(L
));
10056 -- Character literals are always of length 3
10058 if Name_Buffer
(1) = 'Q' then
10061 -- Otherwise loop to adjust for upper/wide chars
10064 Wt
:= Nat
(Name_Len
);
10066 for J
in 1 .. Name_Len
loop
10067 if Name_Buffer
(J
) = 'U' then
10069 elsif Name_Buffer
(J
) = 'W' then
10076 W
:= Int
'Max (W
, Wt
);
10083 Fold_Uint
(N
, UI_From_Int
(W
), Static
);
10088 -- The following attributes denote functions that cannot be folded
10090 when Attribute_From_Any
10092 | Attribute_TypeCode
10096 -- The following attributes can never be folded, and furthermore we
10097 -- should not even have entered the case statement for any of these.
10098 -- Note that in some cases, the values have already been folded as
10099 -- a result of the processing in Analyze_Attribute or earlier in
10102 when Attribute_Abort_Signal
10104 | Attribute_Address
10105 | Attribute_Address_Size
10106 | Attribute_Asm_Input
10107 | Attribute_Asm_Output
10109 | Attribute_Bit_Order
10110 | Attribute_Bit_Position
10111 | Attribute_Callable
10114 | Attribute_Code_Address
10115 | Attribute_Compiler_Version
10117 | Attribute_Default_Bit_Order
10118 | Attribute_Default_Scalar_Storage_Order
10120 | Attribute_Elaborated
10121 | Attribute_Elab_Body
10122 | Attribute_Elab_Spec
10123 | Attribute_Elab_Subp_Body
10124 | Attribute_Enabled
10125 | Attribute_External_Tag
10126 | Attribute_Fast_Math
10127 | Attribute_First_Bit
10130 | Attribute_Last_Bit
10131 | Attribute_Library_Level
10132 | Attribute_Maximum_Alignment
10135 | Attribute_Partition_ID
10136 | Attribute_Pool_Address
10137 | Attribute_Position
10138 | Attribute_Priority
10141 | Attribute_Scalar_Storage_Order
10142 | Attribute_Simple_Storage_Pool
10143 | Attribute_Storage_Pool
10144 | Attribute_Storage_Size
10145 | Attribute_Storage_Unit
10146 | Attribute_Stub_Type
10147 | Attribute_System_Allocator_Alignment
10149 | Attribute_Target_Name
10150 | Attribute_Terminated
10151 | Attribute_To_Address
10152 | Attribute_Type_Key
10153 | Attribute_Unchecked_Access
10154 | Attribute_Universal_Literal_String
10155 | Attribute_Unrestricted_Access
10157 | Attribute_Valid_Scalars
10159 | Attribute_Wchar_T_Size
10160 | Attribute_Wide_Value
10161 | Attribute_Wide_Wide_Value
10162 | Attribute_Word_Size
10165 raise Program_Error
;
10168 -- At the end of the case, one more check. If we did a static evaluation
10169 -- so that the result is now a literal, then set Is_Static_Expression
10170 -- in the constant only if the prefix type is a static subtype. For
10171 -- non-static subtypes, the folding is still OK, but not static.
10173 -- An exception is the GNAT attribute Constrained_Array which is
10174 -- defined to be a static attribute in all cases.
10176 if Nkind_In
(N
, N_Integer_Literal
,
10178 N_Character_Literal
,
10180 or else (Is_Entity_Name
(N
)
10181 and then Ekind
(Entity
(N
)) = E_Enumeration_Literal
)
10183 Set_Is_Static_Expression
(N
, Static
);
10185 -- If this is still an attribute reference, then it has not been folded
10186 -- and that means that its expressions are in a non-static context.
10188 elsif Nkind
(N
) = N_Attribute_Reference
then
10191 -- Note: the else case not covered here are odd cases where the
10192 -- processing has transformed the attribute into something other
10193 -- than a constant. Nothing more to do in such cases.
10198 end Eval_Attribute
;
10200 ------------------------------
10201 -- Is_Anonymous_Tagged_Base --
10202 ------------------------------
10204 function Is_Anonymous_Tagged_Base
10206 Typ
: Entity_Id
) return Boolean
10210 Anon
= Current_Scope
10211 and then Is_Itype
(Anon
)
10212 and then Associated_Node_For_Itype
(Anon
) = Parent
(Typ
);
10213 end Is_Anonymous_Tagged_Base
;
10215 --------------------------------
10216 -- Name_Implies_Lvalue_Prefix --
10217 --------------------------------
10219 function Name_Implies_Lvalue_Prefix
(Nam
: Name_Id
) return Boolean is
10220 pragma Assert
(Is_Attribute_Name
(Nam
));
10222 return Attribute_Name_Implies_Lvalue_Prefix
(Get_Attribute_Id
(Nam
));
10223 end Name_Implies_Lvalue_Prefix
;
10225 -----------------------
10226 -- Resolve_Attribute --
10227 -----------------------
10229 procedure Resolve_Attribute
(N
: Node_Id
; Typ
: Entity_Id
) is
10230 Loc
: constant Source_Ptr
:= Sloc
(N
);
10231 P
: constant Node_Id
:= Prefix
(N
);
10232 Aname
: constant Name_Id
:= Attribute_Name
(N
);
10233 Attr_Id
: constant Attribute_Id
:= Get_Attribute_Id
(Aname
);
10234 Btyp
: constant Entity_Id
:= Base_Type
(Typ
);
10235 Des_Btyp
: Entity_Id
;
10236 Index
: Interp_Index
;
10238 Nom_Subt
: Entity_Id
;
10240 procedure Accessibility_Message
;
10241 -- Error, or warning within an instance, if the static accessibility
10242 -- rules of 3.10.2 are violated.
10244 function Declared_Within_Generic_Unit
10245 (Entity
: Entity_Id
;
10246 Generic_Unit
: Node_Id
) return Boolean;
10247 -- Returns True if Declared_Entity is declared within the declarative
10248 -- region of Generic_Unit; otherwise returns False.
10250 ---------------------------
10251 -- Accessibility_Message --
10252 ---------------------------
10254 procedure Accessibility_Message
is
10255 Indic
: Node_Id
:= Parent
(Parent
(N
));
10258 -- In an instance, this is a runtime check, but one we
10259 -- know will fail, so generate an appropriate warning.
10261 if In_Instance_Body
then
10262 Error_Msg_Warn
:= SPARK_Mode
/= On
;
10264 ("non-local pointer cannot point to local object<<", P
);
10265 Error_Msg_F
("\Program_Error [<<", P
);
10267 Make_Raise_Program_Error
(Loc
,
10268 Reason
=> PE_Accessibility_Check_Failed
));
10269 Set_Etype
(N
, Typ
);
10273 Error_Msg_F
("non-local pointer cannot point to local object", P
);
10275 -- Check for case where we have a missing access definition
10277 if Is_Record_Type
(Current_Scope
)
10279 Nkind_In
(Parent
(N
), N_Discriminant_Association
,
10280 N_Index_Or_Discriminant_Constraint
)
10282 Indic
:= Parent
(Parent
(N
));
10283 while Present
(Indic
)
10284 and then Nkind
(Indic
) /= N_Subtype_Indication
10286 Indic
:= Parent
(Indic
);
10289 if Present
(Indic
) then
10291 ("\use an access definition for" &
10292 " the access discriminant of&",
10293 N
, Entity
(Subtype_Mark
(Indic
)));
10297 end Accessibility_Message
;
10299 ----------------------------------
10300 -- Declared_Within_Generic_Unit --
10301 ----------------------------------
10303 function Declared_Within_Generic_Unit
10304 (Entity
: Entity_Id
;
10305 Generic_Unit
: Node_Id
) return Boolean
10307 Generic_Encloser
: Node_Id
:= Enclosing_Generic_Unit
(Entity
);
10310 while Present
(Generic_Encloser
) loop
10311 if Generic_Encloser
= Generic_Unit
then
10315 -- We have to step to the scope of the generic's entity, because
10316 -- otherwise we'll just get back the same generic.
10318 Generic_Encloser
:=
10319 Enclosing_Generic_Unit
10320 (Scope
(Defining_Entity
(Generic_Encloser
)));
10324 end Declared_Within_Generic_Unit
;
10326 -- Start of processing for Resolve_Attribute
10329 -- If error during analysis, no point in continuing, except for array
10330 -- types, where we get better recovery by using unconstrained indexes
10331 -- than nothing at all (see Check_Array_Type).
10333 if Error_Posted
(N
)
10334 and then Attr_Id
/= Attribute_First
10335 and then Attr_Id
/= Attribute_Last
10336 and then Attr_Id
/= Attribute_Length
10337 and then Attr_Id
/= Attribute_Range
10342 -- If attribute was universal type, reset to actual type
10344 if Etype
(N
) = Universal_Integer
10345 or else Etype
(N
) = Universal_Real
10347 Set_Etype
(N
, Typ
);
10350 -- Remaining processing depends on attribute
10358 -- For access attributes, if the prefix denotes an entity, it is
10359 -- interpreted as a name, never as a call. It may be overloaded,
10360 -- in which case resolution uses the profile of the context type.
10361 -- Otherwise prefix must be resolved.
10363 when Attribute_Access
10364 | Attribute_Unchecked_Access
10365 | Attribute_Unrestricted_Access
10367 -- Note possible modification if we have a variable
10369 if Is_Variable
(P
) then
10371 PN
: constant Node_Id
:= Parent
(N
);
10374 Note
: Boolean := True;
10375 -- Skip this for the case of Unrestricted_Access occuring in
10376 -- the context of a Valid check, since this otherwise leads
10377 -- to a missed warning (the Valid check does not really
10378 -- modify!) If this case, Note will be reset to False.
10380 -- Skip it as well if the type is an Acccess_To_Constant,
10381 -- given that no use of the value can modify the prefix.
10384 if Attr_Id
= Attribute_Unrestricted_Access
10385 and then Nkind
(PN
) = N_Function_Call
10389 if Nkind
(Nm
) = N_Expanded_Name
10390 and then Chars
(Nm
) = Name_Valid
10391 and then Nkind
(Prefix
(Nm
)) = N_Identifier
10392 and then Chars
(Prefix
(Nm
)) = Name_Attr_Long_Float
10397 elsif Is_Access_Constant
(Typ
) then
10402 Note_Possible_Modification
(P
, Sure
=> False);
10407 -- The following comes from a query concerning improper use of
10408 -- universal_access in equality tests involving anonymous access
10409 -- types. Another good reason for 'Ref, but for now disable the
10410 -- test, which breaks several filed tests???
10412 if Ekind
(Typ
) = E_Anonymous_Access_Type
10413 and then Nkind_In
(Parent
(N
), N_Op_Eq
, N_Op_Ne
)
10416 Error_Msg_N
("need unique type to resolve 'Access", N
);
10417 Error_Msg_N
("\qualify attribute with some access type", N
);
10420 -- Case where prefix is an entity name
10422 if Is_Entity_Name
(P
) then
10424 -- Deal with case where prefix itself is overloaded
10426 if Is_Overloaded
(P
) then
10427 Get_First_Interp
(P
, Index
, It
);
10428 while Present
(It
.Nam
) loop
10429 if Type_Conformant
(Designated_Type
(Typ
), It
.Nam
) then
10430 Set_Entity
(P
, It
.Nam
);
10432 -- The prefix is definitely NOT overloaded anymore at
10433 -- this point, so we reset the Is_Overloaded flag to
10434 -- avoid any confusion when reanalyzing the node.
10436 Set_Is_Overloaded
(P
, False);
10437 Set_Is_Overloaded
(N
, False);
10438 Generate_Reference
(Entity
(P
), P
);
10442 Get_Next_Interp
(Index
, It
);
10445 -- If Prefix is a subprogram name, this reference freezes,
10446 -- but not if within spec expression mode. The profile of
10447 -- the subprogram is not frozen at this point.
10449 if not In_Spec_Expression
then
10450 Freeze_Before
(N
, Entity
(P
), Do_Freeze_Profile
=> False);
10453 -- If it is a type, there is nothing to resolve.
10454 -- If it is a subprogram, do not freeze its profile.
10455 -- If it is an object, complete its resolution.
10457 elsif Is_Overloadable
(Entity
(P
)) then
10458 if not In_Spec_Expression
then
10459 Freeze_Before
(N
, Entity
(P
), Do_Freeze_Profile
=> False);
10462 -- Nothing to do if prefix is a type name
10464 elsif Is_Type
(Entity
(P
)) then
10467 -- Otherwise non-overloaded other case, resolve the prefix
10473 -- Some further error checks
10475 Error_Msg_Name_1
:= Aname
;
10477 if not Is_Entity_Name
(P
) then
10480 elsif Is_Overloadable
(Entity
(P
))
10481 and then Is_Abstract_Subprogram
(Entity
(P
))
10483 Error_Msg_F
("prefix of % attribute cannot be abstract", P
);
10484 Set_Etype
(N
, Any_Type
);
10486 elsif Ekind
(Entity
(P
)) = E_Enumeration_Literal
then
10488 ("prefix of % attribute cannot be enumeration literal", P
);
10489 Set_Etype
(N
, Any_Type
);
10491 -- An attempt to take 'Access of a function that renames an
10492 -- enumeration literal. Issue a specialized error message.
10494 elsif Ekind
(Entity
(P
)) = E_Function
10495 and then Present
(Alias
(Entity
(P
)))
10496 and then Ekind
(Alias
(Entity
(P
))) = E_Enumeration_Literal
10499 ("prefix of % attribute cannot be function renaming "
10500 & "an enumeration literal", P
);
10501 Set_Etype
(N
, Any_Type
);
10503 elsif Convention
(Entity
(P
)) = Convention_Intrinsic
then
10504 Error_Msg_F
("prefix of % attribute cannot be intrinsic", P
);
10505 Set_Etype
(N
, Any_Type
);
10508 -- Assignments, return statements, components of aggregates,
10509 -- generic instantiations will require convention checks if
10510 -- the type is an access to subprogram. Given that there will
10511 -- also be accessibility checks on those, this is where the
10512 -- checks can eventually be centralized ???
10514 if Ekind_In
(Btyp
, E_Access_Subprogram_Type
,
10515 E_Anonymous_Access_Subprogram_Type
,
10516 E_Access_Protected_Subprogram_Type
,
10517 E_Anonymous_Access_Protected_Subprogram_Type
)
10519 -- Deal with convention mismatch
10521 if Convention
(Designated_Type
(Btyp
)) /=
10522 Convention
(Entity
(P
))
10525 ("subprogram & has wrong convention", P
, Entity
(P
));
10526 Error_Msg_Sloc
:= Sloc
(Btyp
);
10527 Error_Msg_FE
("\does not match & declared#", P
, Btyp
);
10529 if not Is_Itype
(Btyp
)
10530 and then not Has_Convention_Pragma
(Btyp
)
10533 ("\probable missing pragma Convention for &",
10538 Check_Subtype_Conformant
10539 (New_Id
=> Entity
(P
),
10540 Old_Id
=> Designated_Type
(Btyp
),
10544 if Attr_Id
= Attribute_Unchecked_Access
then
10545 Error_Msg_Name_1
:= Aname
;
10547 ("attribute% cannot be applied to a subprogram", P
);
10549 elsif Aname
= Name_Unrestricted_Access
then
10550 null; -- Nothing to check
10552 -- Check the static accessibility rule of 3.10.2(32).
10553 -- This rule also applies within the private part of an
10554 -- instantiation. This rule does not apply to anonymous
10555 -- access-to-subprogram types in access parameters.
10557 elsif Attr_Id
= Attribute_Access
10558 and then not In_Instance_Body
10560 (Ekind
(Btyp
) = E_Access_Subprogram_Type
10561 or else Is_Local_Anonymous_Access
(Btyp
))
10562 and then Subprogram_Access_Level
(Entity
(P
)) >
10563 Type_Access_Level
(Btyp
)
10566 ("subprogram must not be deeper than access type", P
);
10568 -- Check the restriction of 3.10.2(32) that disallows the
10569 -- access attribute within a generic body when the ultimate
10570 -- ancestor of the type of the attribute is declared outside
10571 -- of the generic unit and the subprogram is declared within
10572 -- that generic unit. This includes any such attribute that
10573 -- occurs within the body of a generic unit that is a child
10574 -- of the generic unit where the subprogram is declared.
10576 -- The rule also prohibits applying the attribute when the
10577 -- access type is a generic formal access type (since the
10578 -- level of the actual type is not known). This restriction
10579 -- does not apply when the attribute type is an anonymous
10580 -- access-to-subprogram type. Note that this check was
10581 -- revised by AI-229, because the original Ada 95 rule
10582 -- was too lax. The original rule only applied when the
10583 -- subprogram was declared within the body of the generic,
10584 -- which allowed the possibility of dangling references).
10585 -- The rule was also too strict in some cases, in that it
10586 -- didn't permit the access to be declared in the generic
10587 -- spec, whereas the revised rule does (as long as it's not
10590 -- There are a couple of subtleties of the test for applying
10591 -- the check that are worth noting. First, we only apply it
10592 -- when the levels of the subprogram and access type are the
10593 -- same (the case where the subprogram is statically deeper
10594 -- was applied above, and the case where the type is deeper
10595 -- is always safe). Second, we want the check to apply
10596 -- within nested generic bodies and generic child unit
10597 -- bodies, but not to apply to an attribute that appears in
10598 -- the generic unit's specification. This is done by testing
10599 -- that the attribute's innermost enclosing generic body is
10600 -- not the same as the innermost generic body enclosing the
10601 -- generic unit where the subprogram is declared (we don't
10602 -- want the check to apply when the access attribute is in
10603 -- the spec and there's some other generic body enclosing
10604 -- generic). Finally, there's no point applying the check
10605 -- when within an instance, because any violations will have
10606 -- been caught by the compilation of the generic unit.
10608 -- We relax this check in Relaxed_RM_Semantics mode for
10609 -- compatibility with legacy code for use by Ada source
10610 -- code analyzers (e.g. CodePeer).
10612 elsif Attr_Id
= Attribute_Access
10613 and then not Relaxed_RM_Semantics
10614 and then not In_Instance
10615 and then Present
(Enclosing_Generic_Unit
(Entity
(P
)))
10616 and then Present
(Enclosing_Generic_Body
(N
))
10617 and then Enclosing_Generic_Body
(N
) /=
10618 Enclosing_Generic_Body
10619 (Enclosing_Generic_Unit
(Entity
(P
)))
10620 and then Subprogram_Access_Level
(Entity
(P
)) =
10621 Type_Access_Level
(Btyp
)
10622 and then Ekind
(Btyp
) /=
10623 E_Anonymous_Access_Subprogram_Type
10624 and then Ekind
(Btyp
) /=
10625 E_Anonymous_Access_Protected_Subprogram_Type
10627 -- The attribute type's ultimate ancestor must be
10628 -- declared within the same generic unit as the
10629 -- subprogram is declared (including within another
10630 -- nested generic unit). The error message is
10631 -- specialized to say "ancestor" for the case where the
10632 -- access type is not its own ancestor, since saying
10633 -- simply "access type" would be very confusing.
10635 if not Declared_Within_Generic_Unit
10637 Enclosing_Generic_Unit
(Entity
(P
)))
10640 ("''Access attribute not allowed in generic body",
10643 if Root_Type
(Btyp
) = Btyp
then
10646 "access type & is declared outside " &
10647 "generic unit (RM 3.10.2(32))", N
, Btyp
);
10650 ("\because ancestor of " &
10651 "access type & is declared outside " &
10652 "generic unit (RM 3.10.2(32))", N
, Btyp
);
10656 ("\move ''Access to private part, or " &
10657 "(Ada 2005) use anonymous access type instead of &",
10660 -- If the ultimate ancestor of the attribute's type is
10661 -- a formal type, then the attribute is illegal because
10662 -- the actual type might be declared at a higher level.
10663 -- The error message is specialized to say "ancestor"
10664 -- for the case where the access type is not its own
10665 -- ancestor, since saying simply "access type" would be
10668 elsif Is_Generic_Type
(Root_Type
(Btyp
)) then
10669 if Root_Type
(Btyp
) = Btyp
then
10671 ("access type must not be a generic formal type",
10675 ("ancestor access type must not be a generic " &
10682 -- If this is a renaming, an inherited operation, or a
10683 -- subprogram instance, use the original entity. This may make
10684 -- the node type-inconsistent, so this transformation can only
10685 -- be done if the node will not be reanalyzed. In particular,
10686 -- if it is within a default expression, the transformation
10687 -- must be delayed until the default subprogram is created for
10688 -- it, when the enclosing subprogram is frozen.
10690 if Is_Entity_Name
(P
)
10691 and then Is_Overloadable
(Entity
(P
))
10692 and then Present
(Alias
(Entity
(P
)))
10693 and then Expander_Active
10696 New_Occurrence_Of
(Alias
(Entity
(P
)), Sloc
(P
)));
10699 elsif Nkind
(P
) = N_Selected_Component
10700 and then Is_Overloadable
(Entity
(Selector_Name
(P
)))
10702 -- Protected operation. If operation is overloaded, must
10703 -- disambiguate. Prefix that denotes protected object itself
10704 -- is resolved with its own type.
10706 if Attr_Id
= Attribute_Unchecked_Access
then
10707 Error_Msg_Name_1
:= Aname
;
10709 ("attribute% cannot be applied to protected operation", P
);
10712 Resolve
(Prefix
(P
));
10713 Generate_Reference
(Entity
(Selector_Name
(P
)), P
);
10715 -- Implement check implied by 3.10.2 (18.1/2) : F.all'access is
10716 -- statically illegal if F is an anonymous access to subprogram.
10718 elsif Nkind
(P
) = N_Explicit_Dereference
10719 and then Is_Entity_Name
(Prefix
(P
))
10720 and then Ekind
(Etype
(Entity
(Prefix
(P
)))) =
10721 E_Anonymous_Access_Subprogram_Type
10723 Error_Msg_N
("anonymous access to subprogram "
10724 & "has deeper accessibility than any master", P
);
10726 elsif Is_Overloaded
(P
) then
10728 -- Use the designated type of the context to disambiguate
10729 -- Note that this was not strictly conformant to Ada 95,
10730 -- but was the implementation adopted by most Ada 95 compilers.
10731 -- The use of the context type to resolve an Access attribute
10732 -- reference is now mandated in AI-235 for Ada 2005.
10735 Index
: Interp_Index
;
10739 Get_First_Interp
(P
, Index
, It
);
10740 while Present
(It
.Typ
) loop
10741 if Covers
(Designated_Type
(Typ
), It
.Typ
) then
10742 Resolve
(P
, It
.Typ
);
10746 Get_Next_Interp
(Index
, It
);
10753 -- X'Access is illegal if X denotes a constant and the access type
10754 -- is access-to-variable. Same for 'Unchecked_Access. The rule
10755 -- does not apply to 'Unrestricted_Access. If the reference is a
10756 -- default-initialized aggregate component for a self-referential
10757 -- type the reference is legal.
10759 if not (Ekind
(Btyp
) = E_Access_Subprogram_Type
10760 or else Ekind
(Btyp
) = E_Anonymous_Access_Subprogram_Type
10761 or else (Is_Record_Type
(Btyp
)
10763 Present
(Corresponding_Remote_Type
(Btyp
)))
10764 or else Ekind
(Btyp
) = E_Access_Protected_Subprogram_Type
10765 or else Ekind
(Btyp
)
10766 = E_Anonymous_Access_Protected_Subprogram_Type
10767 or else Is_Access_Constant
(Btyp
)
10768 or else Is_Variable
(P
)
10769 or else Attr_Id
= Attribute_Unrestricted_Access
)
10771 if Is_Entity_Name
(P
)
10772 and then Is_Type
(Entity
(P
))
10774 -- Legality of a self-reference through an access
10775 -- attribute has been verified in Analyze_Access_Attribute.
10779 elsif Comes_From_Source
(N
) then
10780 Error_Msg_F
("access-to-variable designates constant", P
);
10784 Des_Btyp
:= Designated_Type
(Btyp
);
10786 if Ada_Version
>= Ada_2005
10787 and then Is_Incomplete_Type
(Des_Btyp
)
10789 -- Ada 2005 (AI-412): If the (sub)type is a limited view of an
10790 -- imported entity, and the non-limited view is visible, make
10791 -- use of it. If it is an incomplete subtype, use the base type
10794 if From_Limited_With
(Des_Btyp
)
10795 and then Present
(Non_Limited_View
(Des_Btyp
))
10797 Des_Btyp
:= Non_Limited_View
(Des_Btyp
);
10799 elsif Ekind
(Des_Btyp
) = E_Incomplete_Subtype
then
10800 Des_Btyp
:= Etype
(Des_Btyp
);
10804 if (Attr_Id
= Attribute_Access
10806 Attr_Id
= Attribute_Unchecked_Access
)
10807 and then (Ekind
(Btyp
) = E_General_Access_Type
10808 or else Ekind
(Btyp
) = E_Anonymous_Access_Type
)
10810 -- Ada 2005 (AI-230): Check the accessibility of anonymous
10811 -- access types for stand-alone objects, record and array
10812 -- components, and return objects. For a component definition
10813 -- the level is the same of the enclosing composite type.
10815 if Ada_Version
>= Ada_2005
10816 and then (Is_Local_Anonymous_Access
(Btyp
)
10818 -- Handle cases where Btyp is the anonymous access
10819 -- type of an Ada 2012 stand-alone object.
10821 or else Nkind
(Associated_Node_For_Itype
(Btyp
)) =
10822 N_Object_Declaration
)
10824 Object_Access_Level
(P
) > Deepest_Type_Access_Level
(Btyp
)
10825 and then Attr_Id
= Attribute_Access
10827 -- In an instance, this is a runtime check, but one we know
10828 -- will fail, so generate an appropriate warning. As usual,
10829 -- this kind of warning is an error in SPARK mode.
10831 if In_Instance_Body
then
10832 Error_Msg_Warn
:= SPARK_Mode
/= On
;
10834 ("non-local pointer cannot point to local object<<", P
);
10835 Error_Msg_F
("\Program_Error [<<", P
);
10838 Make_Raise_Program_Error
(Loc
,
10839 Reason
=> PE_Accessibility_Check_Failed
));
10840 Set_Etype
(N
, Typ
);
10844 ("non-local pointer cannot point to local object", P
);
10848 if Is_Dependent_Component_Of_Mutable_Object
(P
) then
10850 ("illegal attribute for discriminant-dependent component",
10854 -- Check static matching rule of 3.10.2(27). Nominal subtype
10855 -- of the prefix must statically match the designated type.
10857 Nom_Subt
:= Etype
(P
);
10859 if Is_Constr_Subt_For_U_Nominal
(Nom_Subt
) then
10860 Nom_Subt
:= Base_Type
(Nom_Subt
);
10863 if Is_Tagged_Type
(Designated_Type
(Typ
)) then
10865 -- If the attribute is in the context of an access
10866 -- parameter, then the prefix is allowed to be of
10867 -- the class-wide type (by AI-127).
10869 if Ekind
(Typ
) = E_Anonymous_Access_Type
then
10870 if not Covers
(Designated_Type
(Typ
), Nom_Subt
)
10871 and then not Covers
(Nom_Subt
, Designated_Type
(Typ
))
10877 Desig
:= Designated_Type
(Typ
);
10879 if Is_Class_Wide_Type
(Desig
) then
10880 Desig
:= Etype
(Desig
);
10883 if Is_Anonymous_Tagged_Base
(Nom_Subt
, Desig
) then
10888 ("type of prefix: & not compatible",
10891 ("\with &, the expected designated type",
10892 P
, Designated_Type
(Typ
));
10897 elsif not Covers
(Designated_Type
(Typ
), Nom_Subt
)
10899 (not Is_Class_Wide_Type
(Designated_Type
(Typ
))
10900 and then Is_Class_Wide_Type
(Nom_Subt
))
10903 ("type of prefix: & is not covered", P
, Nom_Subt
);
10905 ("\by &, the expected designated type" &
10906 " (RM 3.10.2 (27))", P
, Designated_Type
(Typ
));
10909 if Is_Class_Wide_Type
(Designated_Type
(Typ
))
10910 and then Has_Discriminants
(Etype
(Designated_Type
(Typ
)))
10911 and then Is_Constrained
(Etype
(Designated_Type
(Typ
)))
10912 and then Designated_Type
(Typ
) /= Nom_Subt
10914 Apply_Discriminant_Check
10915 (N
, Etype
(Designated_Type
(Typ
)));
10918 -- Ada 2005 (AI-363): Require static matching when designated
10919 -- type has discriminants and a constrained partial view, since
10920 -- in general objects of such types are mutable, so we can't
10921 -- allow the access value to designate a constrained object
10922 -- (because access values must be assumed to designate mutable
10923 -- objects when designated type does not impose a constraint).
10925 elsif Subtypes_Statically_Match
(Des_Btyp
, Nom_Subt
) then
10928 elsif Has_Discriminants
(Designated_Type
(Typ
))
10929 and then not Is_Constrained
(Des_Btyp
)
10931 (Ada_Version
< Ada_2005
10933 not Object_Type_Has_Constrained_Partial_View
10934 (Typ
=> Designated_Type
(Base_Type
(Typ
)),
10935 Scop
=> Current_Scope
))
10941 ("object subtype must statically match "
10942 & "designated subtype", P
);
10944 if Is_Entity_Name
(P
)
10945 and then Is_Array_Type
(Designated_Type
(Typ
))
10948 D
: constant Node_Id
:= Declaration_Node
(Entity
(P
));
10951 ("aliased object has explicit bounds??", D
);
10953 ("\declare without bounds (and with explicit "
10954 & "initialization)??", D
);
10956 ("\for use with unconstrained access??", D
);
10961 -- Check the static accessibility rule of 3.10.2(28). Note that
10962 -- this check is not performed for the case of an anonymous
10963 -- access type, since the access attribute is always legal
10964 -- in such a context.
10966 if Attr_Id
/= Attribute_Unchecked_Access
10967 and then Ekind
(Btyp
) = E_General_Access_Type
10969 Object_Access_Level
(P
) > Deepest_Type_Access_Level
(Btyp
)
10971 Accessibility_Message
;
10976 if Ekind_In
(Btyp
, E_Access_Protected_Subprogram_Type
,
10977 E_Anonymous_Access_Protected_Subprogram_Type
)
10979 if Is_Entity_Name
(P
)
10980 and then not Is_Protected_Type
(Scope
(Entity
(P
)))
10982 Error_Msg_F
("context requires a protected subprogram", P
);
10984 -- Check accessibility of protected object against that of the
10985 -- access type, but only on user code, because the expander
10986 -- creates access references for handlers. If the context is an
10987 -- anonymous_access_to_protected, there are no accessibility
10988 -- checks either. Omit check entirely for Unrestricted_Access.
10990 elsif Object_Access_Level
(P
) > Deepest_Type_Access_Level
(Btyp
)
10991 and then Comes_From_Source
(N
)
10992 and then Ekind
(Btyp
) = E_Access_Protected_Subprogram_Type
10993 and then Attr_Id
/= Attribute_Unrestricted_Access
10995 Accessibility_Message
;
10998 -- AI05-0225: If the context is not an access to protected
10999 -- function, the prefix must be a variable, given that it may
11000 -- be used subsequently in a protected call.
11002 elsif Nkind
(P
) = N_Selected_Component
11003 and then not Is_Variable
(Prefix
(P
))
11004 and then Ekind
(Entity
(Selector_Name
(P
))) /= E_Function
11007 ("target object of access to protected procedure "
11008 & "must be variable", N
);
11010 elsif Is_Entity_Name
(P
) then
11011 Check_Internal_Protected_Use
(N
, Entity
(P
));
11014 elsif Ekind_In
(Btyp
, E_Access_Subprogram_Type
,
11015 E_Anonymous_Access_Subprogram_Type
)
11016 and then Ekind
(Etype
(N
)) = E_Access_Protected_Subprogram_Type
11018 Error_Msg_F
("context requires a non-protected subprogram", P
);
11021 -- The context cannot be a pool-specific type, but this is a
11022 -- legality rule, not a resolution rule, so it must be checked
11023 -- separately, after possibly disambiguation (see AI-245).
11025 if Ekind
(Btyp
) = E_Access_Type
11026 and then Attr_Id
/= Attribute_Unrestricted_Access
11028 Wrong_Type
(N
, Typ
);
11031 -- The context may be a constrained access type (however ill-
11032 -- advised such subtypes might be) so in order to generate a
11033 -- constraint check when needed set the type of the attribute
11034 -- reference to the base type of the context.
11036 Set_Etype
(N
, Btyp
);
11038 -- Check for incorrect atomic/volatile reference (RM C.6(12))
11040 if Attr_Id
/= Attribute_Unrestricted_Access
then
11041 if Is_Atomic_Object
(P
)
11042 and then not Is_Atomic
(Designated_Type
(Typ
))
11045 ("access to atomic object cannot yield access-to-" &
11046 "non-atomic type", P
);
11048 elsif Is_Volatile_Object
(P
)
11049 and then not Is_Volatile
(Designated_Type
(Typ
))
11052 ("access to volatile object cannot yield access-to-" &
11053 "non-volatile type", P
);
11057 -- Check for unrestricted access where expected type is a thin
11058 -- pointer to an unconstrained array.
11060 if Non_Aliased_Prefix
(N
)
11061 and then Has_Size_Clause
(Typ
)
11062 and then RM_Size
(Typ
) = System_Address_Size
11065 DT
: constant Entity_Id
:= Designated_Type
(Typ
);
11067 if Is_Array_Type
(DT
) and then not Is_Constrained
(DT
) then
11069 ("illegal use of Unrestricted_Access attribute", P
);
11071 ("\attempt to generate thin pointer to unaliased "
11077 -- Mark that address of entity is taken in case of
11078 -- 'Unrestricted_Access or in case of a subprogram.
11080 if Is_Entity_Name
(P
)
11081 and then (Attr_Id
= Attribute_Unrestricted_Access
11082 or else Is_Subprogram
(Entity
(P
)))
11084 Set_Address_Taken
(Entity
(P
));
11087 -- Deal with possible elaboration check
11089 if Is_Entity_Name
(P
) and then Is_Subprogram
(Entity
(P
)) then
11091 Subp_Id
: constant Entity_Id
:= Entity
(P
);
11092 Scop
: constant Entity_Id
:= Scope
(Subp_Id
);
11093 Subp_Decl
: constant Node_Id
:=
11094 Unit_Declaration_Node
(Subp_Id
);
11095 Flag_Id
: Entity_Id
;
11096 Subp_Body
: Node_Id
;
11098 -- If the access has been taken and the body of the subprogram
11099 -- has not been see yet, indirect calls must be protected with
11100 -- elaboration checks. We have the proper elaboration machinery
11101 -- for subprograms declared in packages, but within a block or
11102 -- a subprogram the body will appear in the same declarative
11103 -- part, and we must insert a check in the eventual body itself
11104 -- using the elaboration flag that we generate now. The check
11105 -- is then inserted when the body is expanded. This processing
11106 -- is not needed for a stand alone expression function because
11107 -- the internally generated spec and body are always inserted
11108 -- as a pair in the same declarative list.
11112 and then Comes_From_Source
(Subp_Id
)
11113 and then Comes_From_Source
(N
)
11114 and then In_Open_Scopes
(Scop
)
11115 and then Ekind_In
(Scop
, E_Block
, E_Procedure
, E_Function
)
11116 and then not Has_Completion
(Subp_Id
)
11117 and then No
(Elaboration_Entity
(Subp_Id
))
11118 and then Nkind
(Subp_Decl
) = N_Subprogram_Declaration
11119 and then Nkind
(Original_Node
(Subp_Decl
)) /=
11120 N_Expression_Function
11122 -- Create elaboration variable for it
11124 Flag_Id
:= Make_Temporary
(Loc
, 'E');
11125 Set_Elaboration_Entity
(Subp_Id
, Flag_Id
);
11126 Set_Is_Frozen
(Flag_Id
);
11128 -- Insert declaration for flag after subprogram
11129 -- declaration. Note that attribute reference may
11130 -- appear within a nested scope.
11132 Insert_After_And_Analyze
(Subp_Decl
,
11133 Make_Object_Declaration
(Loc
,
11134 Defining_Identifier
=> Flag_Id
,
11135 Object_Definition
=>
11136 New_Occurrence_Of
(Standard_Short_Integer
, Loc
),
11138 Make_Integer_Literal
(Loc
, Uint_0
)));
11141 -- Taking the 'Access of an expression function freezes its
11142 -- expression (RM 13.14 10.3/3). This does not apply to an
11143 -- expression function that acts as a completion because the
11144 -- generated body is immediately analyzed and the expression
11145 -- is automatically frozen.
11147 if Is_Expression_Function
(Subp_Id
)
11148 and then Present
(Corresponding_Body
(Subp_Decl
))
11151 Unit_Declaration_Node
(Corresponding_Body
(Subp_Decl
));
11153 -- The body has already been analyzed when the expression
11154 -- function acts as a completion.
11156 if Analyzed
(Subp_Body
) then
11159 -- Attribute 'Access may appear within the generated body
11160 -- of the expression function subject to the attribute:
11162 -- function F is (... F'Access ...);
11164 -- If the expression function is on the scope stack, then
11165 -- the body is currently being analyzed. Do not reanalyze
11166 -- it because this will lead to infinite recursion.
11168 elsif In_Open_Scopes
(Subp_Id
) then
11171 -- If reference to the expression function appears in an
11172 -- inner scope, for example as an actual in an instance,
11173 -- this is not a freeze point either.
11175 elsif Scope
(Subp_Id
) /= Current_Scope
then
11178 -- Analyze the body of the expression function to freeze
11179 -- the expression. This takes care of the case where the
11180 -- 'Access is part of dispatch table initialization and
11181 -- the generated body of the expression function has not
11182 -- been analyzed yet.
11185 Analyze
(Subp_Body
);
11195 -- Deal with resolving the type for Address attribute, overloading
11196 -- is not permitted here, since there is no context to resolve it.
11198 when Attribute_Address
11199 | Attribute_Code_Address
11201 -- To be safe, assume that if the address of a variable is taken,
11202 -- it may be modified via this address, so note modification.
11204 if Is_Variable
(P
) then
11205 Note_Possible_Modification
(P
, Sure
=> False);
11208 if Nkind
(P
) in N_Subexpr
11209 and then Is_Overloaded
(P
)
11211 Get_First_Interp
(P
, Index
, It
);
11212 Get_Next_Interp
(Index
, It
);
11214 if Present
(It
.Nam
) then
11215 Error_Msg_Name_1
:= Aname
;
11217 ("prefix of % attribute cannot be overloaded", P
);
11221 if not Is_Entity_Name
(P
)
11222 or else not Is_Overloadable
(Entity
(P
))
11224 if not Is_Task_Type
(Etype
(P
))
11225 or else Nkind
(P
) = N_Explicit_Dereference
11231 -- If this is the name of a derived subprogram, or that of a
11232 -- generic actual, the address is that of the original entity.
11234 if Is_Entity_Name
(P
)
11235 and then Is_Overloadable
(Entity
(P
))
11236 and then Present
(Alias
(Entity
(P
)))
11239 New_Occurrence_Of
(Alias
(Entity
(P
)), Sloc
(P
)));
11242 if Is_Entity_Name
(P
) then
11243 Set_Address_Taken
(Entity
(P
));
11246 if Nkind
(P
) = N_Slice
then
11248 -- Arr (X .. Y)'address is identical to Arr (X)'address,
11249 -- even if the array is packed and the slice itself is not
11250 -- addressable. Transform the prefix into an indexed component.
11252 -- Note that the transformation is safe only if we know that
11253 -- the slice is non-null. That is because a null slice can have
11254 -- an out of bounds index value.
11256 -- Right now, gigi blows up if given 'Address on a slice as a
11257 -- result of some incorrect freeze nodes generated by the front
11258 -- end, and this covers up that bug in one case, but the bug is
11259 -- likely still there in the cases not handled by this code ???
11261 -- It's not clear what 'Address *should* return for a null
11262 -- slice with out of bounds indexes, this might be worth an ARG
11265 -- One approach would be to do a length check unconditionally,
11266 -- and then do the transformation below unconditionally, but
11267 -- analyze with checks off, avoiding the problem of the out of
11268 -- bounds index. This approach would interpret the address of
11269 -- an out of bounds null slice as being the address where the
11270 -- array element would be if there was one, which is probably
11271 -- as reasonable an interpretation as any ???
11274 Loc
: constant Source_Ptr
:= Sloc
(P
);
11275 D
: constant Node_Id
:= Discrete_Range
(P
);
11279 if Is_Entity_Name
(D
)
11282 (Type_Low_Bound
(Entity
(D
)),
11283 Type_High_Bound
(Entity
(D
)))
11286 Make_Attribute_Reference
(Loc
,
11287 Prefix
=> (New_Occurrence_Of
(Entity
(D
), Loc
)),
11288 Attribute_Name
=> Name_First
);
11290 elsif Nkind
(D
) = N_Range
11291 and then Not_Null_Range
(Low_Bound
(D
), High_Bound
(D
))
11293 Lo
:= Low_Bound
(D
);
11299 if Present
(Lo
) then
11301 Make_Indexed_Component
(Loc
,
11302 Prefix
=> Relocate_Node
(Prefix
(P
)),
11303 Expressions
=> New_List
(Lo
)));
11305 Analyze_And_Resolve
(P
);
11314 -- Prefix of Body_Version attribute can be a subprogram name which
11315 -- must not be resolved, since this is not a call.
11317 when Attribute_Body_Version
=>
11324 -- Prefix of Caller attribute is an entry name which must not
11325 -- be resolved, since this is definitely not an entry call.
11327 when Attribute_Caller
=>
11334 -- Shares processing with Address attribute
11340 -- If the prefix of the Count attribute is an entry name it must not
11341 -- be resolved, since this is definitely not an entry call. However,
11342 -- if it is an element of an entry family, the index itself may
11343 -- have to be resolved because it can be a general expression.
11345 when Attribute_Count
=>
11346 if Nkind
(P
) = N_Indexed_Component
11347 and then Is_Entity_Name
(Prefix
(P
))
11350 Indx
: constant Node_Id
:= First
(Expressions
(P
));
11351 Fam
: constant Entity_Id
:= Entity
(Prefix
(P
));
11353 Resolve
(Indx
, Entry_Index_Type
(Fam
));
11354 Apply_Range_Check
(Indx
, Entry_Index_Type
(Fam
));
11362 -- Prefix of the Elaborated attribute is a subprogram name which
11363 -- must not be resolved, since this is definitely not a call. Note
11364 -- that it is a library unit, so it cannot be overloaded here.
11366 when Attribute_Elaborated
=>
11373 -- Prefix of Enabled attribute is a check name, which must be treated
11374 -- specially and not touched by Resolve.
11376 when Attribute_Enabled
=>
11383 -- Do not resolve the prefix of Loop_Entry, instead wait until the
11384 -- attribute has been expanded (see Expand_Loop_Entry_Attributes).
11385 -- The delay ensures that any generated checks or temporaries are
11386 -- inserted before the relocated prefix.
11388 when Attribute_Loop_Entry
=>
11391 --------------------
11392 -- Mechanism_Code --
11393 --------------------
11395 -- Prefix of the Mechanism_Code attribute is a function name
11396 -- which must not be resolved. Should we check for overloaded ???
11398 when Attribute_Mechanism_Code
=>
11405 -- Most processing is done in sem_dist, after determining the
11406 -- context type. Node is rewritten as a conversion to a runtime call.
11408 when Attribute_Partition_ID
=>
11409 Process_Partition_Id
(N
);
11416 when Attribute_Pool_Address
=>
11423 -- We replace the Range attribute node with a range expression whose
11424 -- bounds are the 'First and 'Last attributes applied to the same
11425 -- prefix. The reason that we do this transformation here instead of
11426 -- in the expander is that it simplifies other parts of the semantic
11427 -- analysis which assume that the Range has been replaced; thus it
11428 -- must be done even when in semantic-only mode (note that the RM
11429 -- specifically mentions this equivalence, we take care that the
11430 -- prefix is only evaluated once).
11432 when Attribute_Range
=> Range_Attribute
: declare
11438 if not Is_Entity_Name
(P
) or else not Is_Type
(Entity
(P
)) then
11442 Dims
:= Expressions
(N
);
11445 Make_Attribute_Reference
(Loc
,
11446 Prefix
=> Duplicate_Subexpr
(P
, Name_Req
=> True),
11447 Attribute_Name
=> Name_Last
,
11448 Expressions
=> Dims
);
11451 Make_Attribute_Reference
(Loc
,
11453 Attribute_Name
=> Name_First
,
11454 Expressions
=> (Dims
));
11456 -- Do not share the dimension indicator, if present. Even though
11457 -- it is a static constant, its source location may be modified
11458 -- when printing expanded code and node sharing will lead to chaos
11461 if Present
(Dims
) then
11462 Set_Expressions
(LB
, New_List
(New_Copy_Tree
(First
(Dims
))));
11465 -- If the original was marked as Must_Not_Freeze (see code in
11466 -- Sem_Ch3.Make_Index), then make sure the rewriting does not
11469 if Must_Not_Freeze
(N
) then
11470 Set_Must_Not_Freeze
(HB
);
11471 Set_Must_Not_Freeze
(LB
);
11472 Set_Must_Not_Freeze
(Prefix
(HB
));
11473 Set_Must_Not_Freeze
(Prefix
(LB
));
11476 if Raises_Constraint_Error
(Prefix
(N
)) then
11478 -- Preserve Sloc of prefix in the new bounds, so that the
11479 -- posted warning can be removed if we are within unreachable
11482 Set_Sloc
(LB
, Sloc
(Prefix
(N
)));
11483 Set_Sloc
(HB
, Sloc
(Prefix
(N
)));
11486 Rewrite
(N
, Make_Range
(Loc
, LB
, HB
));
11487 Analyze_And_Resolve
(N
, Typ
);
11489 -- Ensure that the expanded range does not have side effects
11491 Force_Evaluation
(LB
);
11492 Force_Evaluation
(HB
);
11494 -- Normally after resolving attribute nodes, Eval_Attribute
11495 -- is called to do any possible static evaluation of the node.
11496 -- However, here since the Range attribute has just been
11497 -- transformed into a range expression it is no longer an
11498 -- attribute node and therefore the call needs to be avoided
11499 -- and is accomplished by simply returning from the procedure.
11502 end Range_Attribute
;
11508 -- We will only come here during the prescan of a spec expression
11509 -- containing a Result attribute. In that case the proper Etype has
11510 -- already been set, and nothing more needs to be done here.
11512 when Attribute_Result
=>
11515 ----------------------
11516 -- Unchecked_Access --
11517 ----------------------
11519 -- Processing is shared with Access
11521 -------------------------
11522 -- Unrestricted_Access --
11523 -------------------------
11525 -- Processing is shared with Access
11531 -- Resolve aggregate components in component associations
11533 when Attribute_Update
=> Update
: declare
11534 Aggr
: constant Node_Id
:= First
(Expressions
(N
));
11535 Typ
: constant Entity_Id
:= Etype
(Prefix
(N
));
11541 -- Set the Etype of the aggregate to that of the prefix, even
11542 -- though the aggregate may not be a proper representation of a
11543 -- value of the type (missing or duplicated associations, etc.)
11544 -- Complete resolution of the prefix. Note that in Ada 2012 it
11545 -- can be a qualified expression that is e.g. an aggregate.
11547 Set_Etype
(Aggr
, Typ
);
11548 Resolve
(Prefix
(N
), Typ
);
11550 -- For an array type, resolve expressions with the component type
11551 -- of the array, and apply constraint checks when needed.
11553 if Is_Array_Type
(Typ
) then
11554 Assoc
:= First
(Component_Associations
(Aggr
));
11555 while Present
(Assoc
) loop
11556 Expr
:= Expression
(Assoc
);
11557 Resolve
(Expr
, Component_Type
(Typ
));
11559 -- For scalar array components set Do_Range_Check when
11560 -- needed. Constraint checking on non-scalar components
11561 -- is done in Aggregate_Constraint_Checks, but only if
11562 -- full analysis is enabled. These flags are not set in
11563 -- the front-end in GnatProve mode.
11565 if Is_Scalar_Type
(Component_Type
(Typ
))
11566 and then not Is_OK_Static_Expression
(Expr
)
11568 if Is_Entity_Name
(Expr
)
11569 and then Etype
(Expr
) = Component_Type
(Typ
)
11574 Set_Do_Range_Check
(Expr
);
11578 -- The choices in the association are static constants,
11579 -- or static aggregates each of whose components belongs
11580 -- to the proper index type. However, they must also
11581 -- belong to the index subtype (s) of the prefix, which
11582 -- may be a subtype (e.g. given by a slice).
11584 -- Choices may also be identifiers with no staticness
11585 -- requirements, in which case they must resolve to the
11594 C
:= First
(Choices
(Assoc
));
11595 while Present
(C
) loop
11596 Indx
:= First_Index
(Etype
(Prefix
(N
)));
11598 if Nkind
(C
) /= N_Aggregate
then
11599 Analyze_And_Resolve
(C
, Etype
(Indx
));
11600 Apply_Constraint_Check
(C
, Etype
(Indx
));
11601 Check_Non_Static_Context
(C
);
11604 C_E
:= First
(Expressions
(C
));
11605 while Present
(C_E
) loop
11606 Analyze_And_Resolve
(C_E
, Etype
(Indx
));
11607 Apply_Constraint_Check
(C_E
, Etype
(Indx
));
11608 Check_Non_Static_Context
(C_E
);
11622 -- For a record type, use type of each component, which is
11623 -- recorded during analysis.
11626 Assoc
:= First
(Component_Associations
(Aggr
));
11627 while Present
(Assoc
) loop
11628 Comp
:= First
(Choices
(Assoc
));
11629 Expr
:= Expression
(Assoc
);
11631 if Nkind
(Comp
) /= N_Others_Choice
11632 and then not Error_Posted
(Comp
)
11634 Resolve
(Expr
, Etype
(Entity
(Comp
)));
11636 if Is_Scalar_Type
(Etype
(Entity
(Comp
)))
11637 and then not Is_OK_Static_Expression
(Expr
)
11639 Set_Do_Range_Check
(Expr
);
11652 -- Apply range check. Note that we did not do this during the
11653 -- analysis phase, since we wanted Eval_Attribute to have a
11654 -- chance at finding an illegal out of range value.
11656 when Attribute_Val
=>
11658 -- Note that we do our own Eval_Attribute call here rather than
11659 -- use the common one, because we need to do processing after
11660 -- the call, as per above comment.
11662 Eval_Attribute
(N
);
11664 -- Eval_Attribute may replace the node with a raise CE, or
11665 -- fold it to a constant. Obviously we only apply a scalar
11666 -- range check if this did not happen.
11668 if Nkind
(N
) = N_Attribute_Reference
11669 and then Attribute_Name
(N
) = Name_Val
11671 Apply_Scalar_Range_Check
(First
(Expressions
(N
)), Btyp
);
11680 -- Prefix of Version attribute can be a subprogram name which
11681 -- must not be resolved, since this is not a call.
11683 when Attribute_Version
=>
11686 ----------------------
11687 -- Other Attributes --
11688 ----------------------
11690 -- For other attributes, resolve prefix unless it is a type. If
11691 -- the attribute reference itself is a type name ('Base and 'Class)
11692 -- then this is only legal within a task or protected record.
11695 if not Is_Entity_Name
(P
) or else not Is_Type
(Entity
(P
)) then
11699 -- If the attribute reference itself is a type name ('Base,
11700 -- 'Class) then this is only legal within a task or protected
11701 -- record. What is this all about ???
11703 if Is_Entity_Name
(N
) and then Is_Type
(Entity
(N
)) then
11704 if Is_Concurrent_Type
(Entity
(N
))
11705 and then In_Open_Scopes
(Entity
(P
))
11710 ("invalid use of subtype name in expression or call", N
);
11714 -- For attributes whose argument may be a string, complete
11715 -- resolution of argument now. This avoids premature expansion
11716 -- (and the creation of transient scopes) before the attribute
11717 -- reference is resolved.
11720 when Attribute_Value
=>
11721 Resolve
(First
(Expressions
(N
)), Standard_String
);
11723 when Attribute_Wide_Value
=>
11724 Resolve
(First
(Expressions
(N
)), Standard_Wide_String
);
11726 when Attribute_Wide_Wide_Value
=>
11727 Resolve
(First
(Expressions
(N
)), Standard_Wide_Wide_String
);
11729 when others => null;
11732 -- If the prefix of the attribute is a class-wide type then it
11733 -- will be expanded into a dispatching call to a predefined
11734 -- primitive. Therefore we must check for potential violation
11735 -- of such restriction.
11737 if Is_Class_Wide_Type
(Etype
(P
)) then
11738 Check_Restriction
(No_Dispatching_Calls
, N
);
11742 -- Normally the Freezing is done by Resolve but sometimes the Prefix
11743 -- is not resolved, in which case the freezing must be done now.
11745 -- For an elaboration check on a subprogram, we do not freeze its type.
11746 -- It may be declared in an unrelated scope, in particular in the case
11747 -- of a generic function whose type may remain unelaborated.
11749 if Attr_Id
= Attribute_Elaborated
then
11753 Freeze_Expression
(P
);
11756 -- Finally perform static evaluation on the attribute reference
11758 Analyze_Dimension
(N
);
11759 Eval_Attribute
(N
);
11760 end Resolve_Attribute
;
11762 ------------------------
11763 -- Set_Boolean_Result --
11764 ------------------------
11766 procedure Set_Boolean_Result
(N
: Node_Id
; B
: Boolean) is
11767 Loc
: constant Source_Ptr
:= Sloc
(N
);
11770 Rewrite
(N
, New_Occurrence_Of
(Standard_True
, Loc
));
11772 Rewrite
(N
, New_Occurrence_Of
(Standard_False
, Loc
));
11774 end Set_Boolean_Result
;
11776 --------------------------------
11777 -- Stream_Attribute_Available --
11778 --------------------------------
11780 function Stream_Attribute_Available
11782 Nam
: TSS_Name_Type
;
11783 Partial_View
: Node_Id
:= Empty
) return Boolean
11785 Etyp
: Entity_Id
:= Typ
;
11787 -- Start of processing for Stream_Attribute_Available
11790 -- We need some comments in this body ???
11792 if Has_Stream_Attribute_Definition
(Typ
, Nam
) then
11796 if Is_Class_Wide_Type
(Typ
) then
11797 return not Is_Limited_Type
(Typ
)
11798 or else Stream_Attribute_Available
(Etype
(Typ
), Nam
);
11801 if Nam
= TSS_Stream_Input
11802 and then Is_Abstract_Type
(Typ
)
11803 and then not Is_Class_Wide_Type
(Typ
)
11808 if not (Is_Limited_Type
(Typ
)
11809 or else (Present
(Partial_View
)
11810 and then Is_Limited_Type
(Partial_View
)))
11815 -- In Ada 2005, Input can invoke Read, and Output can invoke Write
11817 if Nam
= TSS_Stream_Input
11818 and then Ada_Version
>= Ada_2005
11819 and then Stream_Attribute_Available
(Etyp
, TSS_Stream_Read
)
11823 elsif Nam
= TSS_Stream_Output
11824 and then Ada_Version
>= Ada_2005
11825 and then Stream_Attribute_Available
(Etyp
, TSS_Stream_Write
)
11830 -- Case of Read and Write: check for attribute definition clause that
11831 -- applies to an ancestor type.
11833 while Etype
(Etyp
) /= Etyp
loop
11834 Etyp
:= Etype
(Etyp
);
11836 if Has_Stream_Attribute_Definition
(Etyp
, Nam
) then
11841 if Ada_Version
< Ada_2005
then
11843 -- In Ada 95 mode, also consider a non-visible definition
11846 Btyp
: constant Entity_Id
:= Implementation_Base_Type
(Typ
);
11849 and then Stream_Attribute_Available
11850 (Btyp
, Nam
, Partial_View
=> Typ
);
11855 end Stream_Attribute_Available
;