1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2018, 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
;
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 function Statically_Denotes_Object
(N
: Node_Id
) return Boolean;
214 -- Predicate used to check the legality of the prefix to 'Loop_Entry and
215 -- 'Old, when the prefix is not an entity name. Current RM specfies that
216 -- the prefix must be a direct or expanded name, but it has been proposed
217 -- that the prefix be allowed to be a selected component that does not
218 -- depend on a discriminant, or an indexed component with static indices.
219 -- Current code for this predicate implements this more permissive
222 -----------------------
223 -- Analyze_Attribute --
224 -----------------------
226 procedure Analyze_Attribute
(N
: Node_Id
) is
227 Loc
: constant Source_Ptr
:= Sloc
(N
);
228 Aname
: constant Name_Id
:= Attribute_Name
(N
);
229 P
: constant Node_Id
:= Prefix
(N
);
230 Exprs
: constant List_Id
:= Expressions
(N
);
231 Attr_Id
: constant Attribute_Id
:= Get_Attribute_Id
(Aname
);
235 P_Type
: Entity_Id
:= Empty
;
236 -- Type of prefix after analysis
238 P_Base_Type
: Entity_Id
:= Empty
;
239 -- Base type of prefix after analysis
241 -----------------------
242 -- Local Subprograms --
243 -----------------------
245 procedure Address_Checks
;
246 -- Semantic checks for valid use of Address attribute. This was made
247 -- a separate routine with the idea of using it for unrestricted access
248 -- which seems like it should follow the same rules, but that turned
249 -- out to be impractical. So now this is only used for Address.
251 procedure Analyze_Access_Attribute
;
252 -- Used for Access, Unchecked_Access, Unrestricted_Access attributes.
253 -- Internally, Id distinguishes which of the three cases is involved.
255 procedure Analyze_Attribute_Old_Result
256 (Legal
: out Boolean;
257 Spec_Id
: out Entity_Id
);
258 -- Common processing for attributes 'Old and 'Result. The routine checks
259 -- that the attribute appears in a postcondition-like aspect or pragma
260 -- associated with a suitable subprogram or a body. Flag Legal is set
261 -- when the above criteria are met. Spec_Id denotes the entity of the
262 -- subprogram [body] or Empty if the attribute is illegal.
264 procedure Analyze_Image_Attribute
(Str_Typ
: Entity_Id
);
265 -- Common processing for attributes 'Img, 'Image, 'Wide_Image, and
266 -- 'Wide_Wide_Image. The routine checks that the prefix is valid and
267 -- sets the type of the attribute to the one specified by Str_Typ (e.g.
268 -- Standard_String for 'Image and Standard_Wide_String for 'Wide_Image).
270 procedure Bad_Attribute_For_Predicate
;
271 -- Output error message for use of a predicate (First, Last, Range) not
272 -- allowed with a type that has predicates. If the type is a generic
273 -- actual, then the message is a warning, and we generate code to raise
274 -- program error with an appropriate reason. No error message is given
275 -- for internally generated uses of the attributes. This legality rule
276 -- only applies to scalar types.
278 procedure Check_Array_Or_Scalar_Type
;
279 -- Common procedure used by First, Last, Range attribute to check
280 -- that the prefix is a constrained array or scalar type, or a name
281 -- of an array object, and that an argument appears only if appropriate
282 -- (i.e. only in the array case).
284 procedure Check_Array_Type
;
285 -- Common semantic checks for all array attributes. Checks that the
286 -- prefix is a constrained array type or the name of an array object.
287 -- The error message for non-arrays is specialized appropriately.
289 procedure Check_Asm_Attribute
;
290 -- Common semantic checks for Asm_Input and Asm_Output attributes
292 procedure Check_Component
;
293 -- Common processing for Bit_Position, First_Bit, Last_Bit, and
294 -- Position. Checks prefix is an appropriate selected component.
296 procedure Check_Decimal_Fixed_Point_Type
;
297 -- Check that prefix of attribute N is a decimal fixed-point type
299 procedure Check_Dereference
;
300 -- If the prefix of attribute is an object of an access type, then
301 -- introduce an explicit dereference, and adjust P_Type accordingly.
303 procedure Check_Discrete_Type
;
304 -- Verify that prefix of attribute N is a discrete type
307 -- Check that no attribute arguments are present
309 procedure Check_Either_E0_Or_E1
;
310 -- Check that there are zero or one attribute arguments present
313 -- Check that exactly one attribute argument is present
316 -- Check that two attribute arguments are present
318 procedure Check_Enum_Image
;
319 -- If the prefix type of 'Image is an enumeration type, set all its
320 -- literals as referenced, since the image function could possibly end
321 -- up referencing any of the literals indirectly. Same for Enum_Val.
322 -- Set the flag only if the reference is in the main code unit. Same
323 -- restriction when resolving 'Value; otherwise an improperly set
324 -- reference when analyzing an inlined body will lose a proper
325 -- warning on a useless with_clause.
327 procedure Check_First_Last_Valid
;
328 -- Perform all checks for First_Valid and Last_Valid attributes
330 procedure Check_Fixed_Point_Type
;
331 -- Verify that prefix of attribute N is a fixed type
333 procedure Check_Fixed_Point_Type_0
;
334 -- Verify that prefix of attribute N is a fixed type and that
335 -- no attribute expressions are present.
337 procedure Check_Floating_Point_Type
;
338 -- Verify that prefix of attribute N is a float type
340 procedure Check_Floating_Point_Type_0
;
341 -- Verify that prefix of attribute N is a float type and that
342 -- no attribute expressions are present.
344 procedure Check_Floating_Point_Type_1
;
345 -- Verify that prefix of attribute N is a float type and that
346 -- exactly one attribute expression is present.
348 procedure Check_Floating_Point_Type_2
;
349 -- Verify that prefix of attribute N is a float type and that
350 -- two attribute expressions are present
352 procedure Check_SPARK_05_Restriction_On_Attribute
;
353 -- Issue an error in formal mode because attribute N is allowed
355 procedure Check_Integer_Type
;
356 -- Verify that prefix of attribute N is an integer type
358 procedure Check_Modular_Integer_Type
;
359 -- Verify that prefix of attribute N is a modular integer type
361 procedure Check_Not_CPP_Type
;
362 -- Check that P (the prefix of the attribute) is not an CPP type
363 -- for which no Ada predefined primitive is available.
365 procedure Check_Not_Incomplete_Type
;
366 -- Check that P (the prefix of the attribute) is not an incomplete
367 -- type or a private type for which no full view has been given.
369 procedure Check_Object_Reference
(P
: Node_Id
);
370 -- Check that P is an object reference
372 procedure Check_PolyORB_Attribute
;
373 -- Validity checking for PolyORB/DSA attribute
375 procedure Check_Program_Unit
;
376 -- Verify that prefix of attribute N is a program unit
378 procedure Check_Real_Type
;
379 -- Verify that prefix of attribute N is fixed or float type
381 procedure Check_Scalar_Type
;
382 -- Verify that prefix of attribute N is a scalar type
384 procedure Check_Standard_Prefix
;
385 -- Verify that prefix of attribute N is package Standard. Also checks
386 -- that there are no arguments.
388 procedure Check_Stream_Attribute
(Nam
: TSS_Name_Type
);
389 -- Validity checking for stream attribute. Nam is the TSS name of the
390 -- corresponding possible defined attribute function (e.g. for the
391 -- Read attribute, Nam will be TSS_Stream_Read).
393 procedure Check_System_Prefix
;
394 -- Verify that prefix of attribute N is package System
396 procedure Check_Task_Prefix
;
397 -- Verify that prefix of attribute N is a task or task type
399 procedure Check_Type
;
400 -- Verify that the prefix of attribute N is a type
402 procedure Check_Unit_Name
(Nod
: Node_Id
);
403 -- Check that Nod is of the form of a library unit name, i.e that
404 -- it is an identifier, or a selected component whose prefix is
405 -- itself of the form of a library unit name. Note that this is
406 -- quite different from Check_Program_Unit, since it only checks
407 -- the syntactic form of the name, not the semantic identity. This
408 -- is because it is used with attributes (Elab_Body, Elab_Spec and
409 -- Elaborated) which can refer to non-visible unit.
411 procedure Error_Attr
(Msg
: String; Error_Node
: Node_Id
);
412 pragma No_Return
(Error_Attr
);
413 procedure Error_Attr
;
414 pragma No_Return
(Error_Attr
);
415 -- Posts error using Error_Msg_N at given node, sets type of attribute
416 -- node to Any_Type, and then raises Bad_Attribute to avoid any further
417 -- semantic processing. The message typically contains a % insertion
418 -- character which is replaced by the attribute name. The call with
419 -- no arguments is used when the caller has already generated the
420 -- required error messages.
422 procedure Error_Attr_P
(Msg
: String);
423 pragma No_Return
(Error_Attr_P
);
424 -- Like Error_Attr, but error is posted at the start of the prefix
426 procedure Legal_Formal_Attribute
;
427 -- Common processing for attributes Definite and Has_Discriminants.
428 -- Checks that prefix is generic indefinite formal type.
430 procedure Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
;
431 -- Common processing for attributes Max_Alignment_For_Allocation and
432 -- Max_Size_In_Storage_Elements.
435 -- Common processing for attributes Max and Min
437 procedure Standard_Attribute
(Val
: Int
);
438 -- Used to process attributes whose prefix is package Standard which
439 -- yield values of type Universal_Integer. The attribute reference
440 -- node is rewritten with an integer literal of the given value which
441 -- is marked as static.
443 procedure Uneval_Old_Msg
;
444 -- Called when Loop_Entry or Old is used in a potentially unevaluated
445 -- expression. Generates appropriate message or warning depending on
446 -- the setting of Opt.Uneval_Old (or flags in an N_Aspect_Specification
447 -- node in the aspect case).
449 procedure Unexpected_Argument
(En
: Node_Id
);
450 pragma No_Return
(Unexpected_Argument
);
451 -- Signal unexpected attribute argument (En is the argument), and then
452 -- raises Bad_Attribute to avoid any further semantic processing.
454 procedure Validate_Non_Static_Attribute_Function_Call
;
455 -- Called when processing an attribute that is a function call to a
456 -- non-static function, i.e. an attribute function that either takes
457 -- non-scalar arguments or returns a non-scalar result. Verifies that
458 -- such a call does not appear in a preelaborable context.
464 procedure Address_Checks
is
466 -- An Address attribute created by expansion is legal even when it
467 -- applies to other entity-denoting expressions.
469 if not Comes_From_Source
(N
) then
472 -- Address attribute on a protected object self reference is legal
474 elsif Is_Protected_Self_Reference
(P
) then
477 -- Address applied to an entity
479 elsif Is_Entity_Name
(P
) then
481 Ent
: constant Entity_Id
:= Entity
(P
);
484 if Is_Subprogram
(Ent
) then
485 Set_Address_Taken
(Ent
);
486 Kill_Current_Values
(Ent
);
488 -- An Address attribute is accepted when generated by the
489 -- compiler for dispatching operation, and an error is
490 -- issued once the subprogram is frozen (to avoid confusing
491 -- errors about implicit uses of Address in the dispatch
492 -- table initialization).
494 if Has_Pragma_Inline_Always
(Entity
(P
))
495 and then Comes_From_Source
(P
)
498 ("prefix of % attribute cannot be Inline_Always "
501 -- It is illegal to apply 'Address to an intrinsic
502 -- subprogram. This is now formalized in AI05-0095.
503 -- In an instance, an attempt to obtain 'Address of an
504 -- intrinsic subprogram (e.g the renaming of a predefined
505 -- operator that is an actual) raises Program_Error.
507 elsif Convention
(Ent
) = Convention_Intrinsic
then
510 Make_Raise_Program_Error
(Loc
,
511 Reason
=> PE_Address_Of_Intrinsic
));
514 Error_Msg_Name_1
:= Aname
;
516 ("cannot take % of intrinsic subprogram", N
);
519 -- Issue an error if prefix denotes an eliminated subprogram
522 Check_For_Eliminated_Subprogram
(P
, Ent
);
525 -- Object or label reference
527 elsif Is_Object
(Ent
) or else Ekind
(Ent
) = E_Label
then
528 Set_Address_Taken
(Ent
);
530 -- Deal with No_Implicit_Aliasing restriction
532 if Restriction_Check_Required
(No_Implicit_Aliasing
) then
533 if not Is_Aliased_View
(P
) then
534 Check_Restriction
(No_Implicit_Aliasing
, P
);
536 Check_No_Implicit_Aliasing
(P
);
540 -- If we have an address of an object, and the attribute
541 -- comes from source, then set the object as potentially
542 -- source modified. We do this because the resulting address
543 -- can potentially be used to modify the variable and we
544 -- might not detect this, leading to some junk warnings.
546 Set_Never_Set_In_Source
(Ent
, False);
548 -- Allow Address to be applied to task or protected type,
549 -- returning null address (what is that about???)
551 elsif (Is_Concurrent_Type
(Etype
(Ent
))
552 and then Etype
(Ent
) = Base_Type
(Ent
))
553 or else Ekind
(Ent
) = E_Package
554 or else Is_Generic_Unit
(Ent
)
557 New_Occurrence_Of
(RTE
(RE_Null_Address
), Sloc
(N
)));
559 -- Anything else is illegal
562 Error_Attr
("invalid prefix for % attribute", P
);
568 elsif Is_Object_Reference
(P
) then
571 -- Subprogram called using dot notation
573 elsif Nkind
(P
) = N_Selected_Component
574 and then Is_Subprogram
(Entity
(Selector_Name
(P
)))
578 -- What exactly are we allowing here ??? and is this properly
579 -- documented in the sinfo documentation for this node ???
581 elsif Relaxed_RM_Semantics
582 and then Nkind
(P
) = N_Attribute_Reference
586 -- All other non-entity name cases are illegal
589 Error_Attr
("invalid prefix for % attribute", P
);
593 ------------------------------
594 -- Analyze_Access_Attribute --
595 ------------------------------
597 procedure Analyze_Access_Attribute
is
598 Acc_Type
: Entity_Id
;
603 function Build_Access_Object_Type
(DT
: Entity_Id
) return Entity_Id
;
604 -- Build an access-to-object type whose designated type is DT,
605 -- and whose Ekind is appropriate to the attribute type. The
606 -- type that is constructed is returned as the result.
608 procedure Build_Access_Subprogram_Type
(P
: Node_Id
);
609 -- Build an access to subprogram whose designated type is the type of
610 -- the prefix. If prefix is overloaded, so is the node itself. The
611 -- result is stored in Acc_Type.
613 function OK_Self_Reference
return Boolean;
614 -- An access reference whose prefix is a type can legally appear
615 -- within an aggregate, where it is obtained by expansion of
616 -- a defaulted aggregate. The enclosing aggregate that contains
617 -- the self-referenced is flagged so that the self-reference can
618 -- be expanded into a reference to the target object (see exp_aggr).
620 ------------------------------
621 -- Build_Access_Object_Type --
622 ------------------------------
624 function Build_Access_Object_Type
(DT
: Entity_Id
) return Entity_Id
is
625 Typ
: constant Entity_Id
:=
627 (E_Access_Attribute_Type
, Current_Scope
, Loc
, 'A');
629 Set_Etype
(Typ
, Typ
);
631 Set_Associated_Node_For_Itype
(Typ
, N
);
632 Set_Directly_Designated_Type
(Typ
, DT
);
634 end Build_Access_Object_Type
;
636 ----------------------------------
637 -- Build_Access_Subprogram_Type --
638 ----------------------------------
640 procedure Build_Access_Subprogram_Type
(P
: Node_Id
) is
641 Index
: Interp_Index
;
644 procedure Check_Local_Access
(E
: Entity_Id
);
645 -- Deal with possible access to local subprogram. If we have such
646 -- an access, we set a flag to kill all tracked values on any call
647 -- because this access value may be passed around, and any called
648 -- code might use it to access a local procedure which clobbers a
649 -- tracked value. If the scope is a loop or block, indicate that
650 -- value tracking is disabled for the enclosing subprogram.
652 function Get_Kind
(E
: Entity_Id
) return Entity_Kind
;
653 -- Distinguish between access to regular/protected subprograms
655 ------------------------
656 -- Check_Local_Access --
657 ------------------------
659 procedure Check_Local_Access
(E
: Entity_Id
) is
661 if not Is_Library_Level_Entity
(E
) then
662 Set_Suppress_Value_Tracking_On_Call
(Current_Scope
);
663 Set_Suppress_Value_Tracking_On_Call
664 (Nearest_Dynamic_Scope
(Current_Scope
));
666 end Check_Local_Access
;
672 function Get_Kind
(E
: Entity_Id
) return Entity_Kind
is
674 if Convention
(E
) = Convention_Protected
then
675 return E_Access_Protected_Subprogram_Type
;
677 return E_Access_Subprogram_Type
;
681 -- Start of processing for Build_Access_Subprogram_Type
684 -- In the case of an access to subprogram, use the name of the
685 -- subprogram itself as the designated type. Type-checking in
686 -- this case compares the signatures of the designated types.
688 -- Note: This fragment of the tree is temporarily malformed
689 -- because the correct tree requires an E_Subprogram_Type entity
690 -- as the designated type. In most cases this designated type is
691 -- later overridden by the semantics with the type imposed by the
692 -- context during the resolution phase. In the specific case of
693 -- the expression Address!(Prim'Unrestricted_Access), used to
694 -- initialize slots of dispatch tables, this work will be done by
695 -- the expander (see Exp_Aggr).
697 -- The reason to temporarily add this kind of node to the tree
698 -- instead of a proper E_Subprogram_Type itype, is the following:
699 -- in case of errors found in the source file we report better
700 -- error messages. For example, instead of generating the
703 -- "expected access to subprogram with profile
704 -- defined at line X"
706 -- we currently generate:
708 -- "expected access to function Z defined at line X"
710 Set_Etype
(N
, Any_Type
);
712 if not Is_Overloaded
(P
) then
713 Check_Local_Access
(Entity
(P
));
715 if not Is_Intrinsic_Subprogram
(Entity
(P
)) then
716 Acc_Type
:= Create_Itype
(Get_Kind
(Entity
(P
)), N
);
717 Set_Is_Public
(Acc_Type
, False);
718 Set_Etype
(Acc_Type
, Acc_Type
);
719 Set_Convention
(Acc_Type
, Convention
(Entity
(P
)));
720 Set_Directly_Designated_Type
(Acc_Type
, Entity
(P
));
721 Set_Etype
(N
, Acc_Type
);
722 Freeze_Before
(N
, Acc_Type
);
726 Get_First_Interp
(P
, Index
, It
);
727 while Present
(It
.Nam
) loop
728 Check_Local_Access
(It
.Nam
);
730 if not Is_Intrinsic_Subprogram
(It
.Nam
) then
731 Acc_Type
:= Create_Itype
(Get_Kind
(It
.Nam
), N
);
732 Set_Is_Public
(Acc_Type
, False);
733 Set_Etype
(Acc_Type
, Acc_Type
);
734 Set_Convention
(Acc_Type
, Convention
(It
.Nam
));
735 Set_Directly_Designated_Type
(Acc_Type
, It
.Nam
);
736 Add_One_Interp
(N
, Acc_Type
, Acc_Type
);
737 Freeze_Before
(N
, Acc_Type
);
740 Get_Next_Interp
(Index
, It
);
744 -- Cannot be applied to intrinsic. Looking at the tests above,
745 -- the only way Etype (N) can still be set to Any_Type is if
746 -- Is_Intrinsic_Subprogram was True for some referenced entity.
748 if Etype
(N
) = Any_Type
then
749 Error_Attr_P
("prefix of % attribute cannot be intrinsic");
751 end Build_Access_Subprogram_Type
;
753 ----------------------
754 -- OK_Self_Reference --
755 ----------------------
757 function OK_Self_Reference
return Boolean is
764 (Nkind
(Par
) = N_Component_Association
765 or else Nkind
(Par
) in N_Subexpr
)
767 if Nkind_In
(Par
, N_Aggregate
, N_Extension_Aggregate
) then
768 if Etype
(Par
) = Typ
then
769 Set_Has_Self_Reference
(Par
);
771 -- Check the context: the aggregate must be part of the
772 -- initialization of a type or component, or it is the
773 -- resulting expansion in an initialization procedure.
775 if Is_Init_Proc
(Current_Scope
) then
779 while Present
(Par
) loop
780 if Nkind
(Par
) = N_Full_Type_Declaration
then
795 -- No enclosing aggregate, or not a self-reference
798 end OK_Self_Reference
;
800 -- Start of processing for Analyze_Access_Attribute
803 Check_SPARK_05_Restriction_On_Attribute
;
806 if Nkind
(P
) = N_Character_Literal
then
808 ("prefix of % attribute cannot be enumeration literal");
811 -- Preserve relevant elaboration-related attributes of the context
812 -- which are no longer available or very expensive to recompute once
813 -- analysis, resolution, and expansion are over.
815 Mark_Elaboration_Attributes
820 -- Save the scenario for later examination by the ABE Processing
823 Record_Elaboration_Scenario
(N
);
825 -- Case of access to subprogram
827 if Is_Entity_Name
(P
) and then Is_Overloadable
(Entity
(P
)) then
828 if Has_Pragma_Inline_Always
(Entity
(P
)) then
830 ("prefix of % attribute cannot be Inline_Always subprogram");
832 elsif Aname
= Name_Unchecked_Access
then
833 Error_Attr
("attribute% cannot be applied to a subprogram", P
);
836 -- Issue an error if the prefix denotes an eliminated subprogram
838 Check_For_Eliminated_Subprogram
(P
, Entity
(P
));
840 -- Check for obsolescent subprogram reference
842 Check_Obsolescent_2005_Entity
(Entity
(P
), P
);
844 -- Build the appropriate subprogram type
846 Build_Access_Subprogram_Type
(P
);
848 -- For P'Access or P'Unrestricted_Access, where P is a nested
849 -- subprogram, we might be passing P to another subprogram (but we
850 -- don't check that here), which might call P. P could modify
851 -- local variables, so we need to kill current values. It is
852 -- important not to do this for library-level subprograms, because
853 -- Kill_Current_Values is very inefficient in the case of library
854 -- level packages with lots of tagged types.
856 if Is_Library_Level_Entity
(Entity
(Prefix
(N
))) then
859 -- Do not kill values on nodes initializing dispatch tables
860 -- slots. The construct Prim_Ptr!(Prim'Unrestricted_Access)
861 -- is currently generated by the expander only for this
862 -- purpose. Done to keep the quality of warnings currently
863 -- generated by the compiler (otherwise any declaration of
864 -- a tagged type cleans constant indications from its scope).
866 elsif Nkind
(Parent
(N
)) = N_Unchecked_Type_Conversion
867 and then (Etype
(Parent
(N
)) = RTE
(RE_Prim_Ptr
)
869 Etype
(Parent
(N
)) = RTE
(RE_Size_Ptr
))
870 and then Is_Dispatching_Operation
871 (Directly_Designated_Type
(Etype
(N
)))
879 -- In the static elaboration model, treat the attribute reference
880 -- as a subprogram call for elaboration purposes. Suppress this
881 -- treatment under debug flag. In any case, we are all done.
883 if Legacy_Elaboration_Checks
884 and not Dynamic_Elaboration_Checks
885 and not Debug_Flag_Dot_UU
892 -- Component is an operation of a protected type
894 elsif Nkind
(P
) = N_Selected_Component
895 and then Is_Overloadable
(Entity
(Selector_Name
(P
)))
897 if Ekind
(Entity
(Selector_Name
(P
))) = E_Entry
then
898 Error_Attr_P
("prefix of % attribute must be subprogram");
901 Build_Access_Subprogram_Type
(Selector_Name
(P
));
905 -- Deal with incorrect reference to a type, but note that some
906 -- accesses are allowed: references to the current type instance,
907 -- or in Ada 2005 self-referential pointer in a default-initialized
910 if Is_Entity_Name
(P
) then
913 -- The reference may appear in an aggregate that has been expanded
914 -- into a loop. Locate scope of type definition, if any.
916 Scop
:= Current_Scope
;
917 while Ekind
(Scop
) = E_Loop
loop
918 Scop
:= Scope
(Scop
);
921 if Is_Type
(Typ
) then
923 -- OK if we are within the scope of a limited type
924 -- let's mark the component as having per object constraint
926 if Is_Anonymous_Tagged_Base
(Scop
, Typ
) then
934 Q
: Node_Id
:= Parent
(N
);
938 and then Nkind
(Q
) /= N_Component_Declaration
944 Set_Has_Per_Object_Constraint
945 (Defining_Identifier
(Q
), True);
949 if Nkind
(P
) = N_Expanded_Name
then
951 ("current instance prefix must be a direct name", P
);
954 -- If a current instance attribute appears in a component
955 -- constraint it must appear alone; other contexts (spec-
956 -- expressions, within a task body) are not subject to this
959 if not In_Spec_Expression
960 and then not Has_Completion
(Scop
)
962 Nkind_In
(Parent
(N
), N_Discriminant_Association
,
963 N_Index_Or_Discriminant_Constraint
)
966 ("current instance attribute must appear alone", N
);
969 if Is_CPP_Class
(Root_Type
(Typ
)) then
971 ("??current instance unsupported for derivations of "
972 & "'C'P'P types", N
);
975 -- OK if we are in initialization procedure for the type
976 -- in question, in which case the reference to the type
977 -- is rewritten as a reference to the current object.
979 elsif Ekind
(Scop
) = E_Procedure
980 and then Is_Init_Proc
(Scop
)
981 and then Etype
(First_Formal
(Scop
)) = Typ
984 Make_Attribute_Reference
(Loc
,
985 Prefix
=> Make_Identifier
(Loc
, Name_uInit
),
986 Attribute_Name
=> Name_Unrestricted_Access
));
990 -- OK if a task type, this test needs sharpening up ???
992 elsif Is_Task_Type
(Typ
) then
995 -- OK if self-reference in an aggregate in Ada 2005, and
996 -- the reference comes from a copied default expression.
998 -- Note that we check legality of self-reference even if the
999 -- expression comes from source, e.g. when a single component
1000 -- association in an aggregate has a box association.
1002 elsif Ada_Version
>= Ada_2005
1003 and then OK_Self_Reference
1007 -- OK if reference to current instance of a protected object
1009 elsif Is_Protected_Self_Reference
(P
) then
1012 -- Otherwise we have an error case
1015 Error_Attr
("% attribute cannot be applied to type", P
);
1021 -- If we fall through, we have a normal access to object case
1023 -- Unrestricted_Access is (for now) legal wherever an allocator would
1024 -- be legal, so its Etype is set to E_Allocator. The expected type
1025 -- of the other attributes is a general access type, and therefore
1026 -- we label them with E_Access_Attribute_Type.
1028 if not Is_Overloaded
(P
) then
1029 Acc_Type
:= Build_Access_Object_Type
(P_Type
);
1030 Set_Etype
(N
, Acc_Type
);
1034 Index
: Interp_Index
;
1037 Set_Etype
(N
, Any_Type
);
1038 Get_First_Interp
(P
, Index
, It
);
1039 while Present
(It
.Typ
) loop
1040 Acc_Type
:= Build_Access_Object_Type
(It
.Typ
);
1041 Add_One_Interp
(N
, Acc_Type
, Acc_Type
);
1042 Get_Next_Interp
(Index
, It
);
1047 -- Special cases when we can find a prefix that is an entity name
1056 if Is_Entity_Name
(PP
) then
1059 -- If we have an access to an object, and the attribute
1060 -- comes from source, then set the object as potentially
1061 -- source modified. We do this because the resulting access
1062 -- pointer can be used to modify the variable, and we might
1063 -- not detect this, leading to some junk warnings.
1065 -- We only do this for source references, since otherwise
1066 -- we can suppress warnings, e.g. from the unrestricted
1067 -- access generated for validity checks in -gnatVa mode.
1069 if Comes_From_Source
(N
) then
1070 Set_Never_Set_In_Source
(Ent
, False);
1073 -- Mark entity as address taken in the case of
1074 -- 'Unrestricted_Access or subprograms, and kill current
1077 if Aname
= Name_Unrestricted_Access
1078 or else Is_Subprogram
(Ent
)
1080 Set_Address_Taken
(Ent
);
1083 Kill_Current_Values
(Ent
);
1086 elsif Nkind_In
(PP
, N_Selected_Component
,
1087 N_Indexed_Component
)
1096 end Analyze_Access_Attribute
;
1098 ----------------------------------
1099 -- Analyze_Attribute_Old_Result --
1100 ----------------------------------
1102 procedure Analyze_Attribute_Old_Result
1103 (Legal
: out Boolean;
1104 Spec_Id
: out Entity_Id
)
1106 procedure Check_Placement_In_Check
(Prag
: Node_Id
);
1107 -- Verify that the attribute appears within pragma Check that mimics
1110 procedure Check_Placement_In_Contract_Cases
(Prag
: Node_Id
);
1111 -- Verify that the attribute appears within a consequence of aspect
1112 -- or pragma Contract_Cases denoted by Prag.
1114 procedure Check_Placement_In_Test_Case
(Prag
: Node_Id
);
1115 -- Verify that the attribute appears within the "Ensures" argument of
1116 -- aspect or pragma Test_Case denoted by Prag.
1120 Encl_Nod
: Node_Id
) return Boolean;
1121 -- Subsidiary to Check_Placemenet_In_XXX. Determine whether arbitrary
1122 -- node Nod is within enclosing node Encl_Nod.
1124 procedure Placement_Error
;
1125 pragma No_Return
(Placement_Error
);
1126 -- Emit a general error when the attributes does not appear in a
1127 -- postcondition-like aspect or pragma, and then raises Bad_Attribute
1128 -- to avoid any further semantic processing.
1130 ------------------------------
1131 -- Check_Placement_In_Check --
1132 ------------------------------
1134 procedure Check_Placement_In_Check
(Prag
: Node_Id
) is
1135 Args
: constant List_Id
:= Pragma_Argument_Associations
(Prag
);
1136 Nam
: constant Name_Id
:= Chars
(Get_Pragma_Arg
(First
(Args
)));
1139 -- The "Name" argument of pragma Check denotes a postcondition
1141 if Nam_In
(Nam
, Name_Post
,
1148 -- Otherwise the placement of the attribute is illegal
1153 end Check_Placement_In_Check
;
1155 ---------------------------------------
1156 -- Check_Placement_In_Contract_Cases --
1157 ---------------------------------------
1159 procedure Check_Placement_In_Contract_Cases
(Prag
: Node_Id
) is
1165 -- Obtain the argument of the aspect or pragma
1167 if Nkind
(Prag
) = N_Aspect_Specification
then
1170 Arg
:= First
(Pragma_Argument_Associations
(Prag
));
1173 Cases
:= Expression
(Arg
);
1175 if Present
(Component_Associations
(Cases
)) then
1176 CCase
:= First
(Component_Associations
(Cases
));
1177 while Present
(CCase
) loop
1179 -- Detect whether the attribute appears within the
1180 -- consequence of the current contract case.
1182 if Nkind
(CCase
) = N_Component_Association
1183 and then Is_Within
(N
, Expression
(CCase
))
1192 -- Otherwise aspect or pragma Contract_Cases is either malformed
1193 -- or the attribute does not appear within a consequence.
1196 ("attribute % must appear in the consequence of a contract case",
1198 end Check_Placement_In_Contract_Cases
;
1200 ----------------------------------
1201 -- Check_Placement_In_Test_Case --
1202 ----------------------------------
1204 procedure Check_Placement_In_Test_Case
(Prag
: Node_Id
) is
1205 Arg
: constant Node_Id
:=
1208 Arg_Nam
=> Name_Ensures
,
1209 From_Aspect
=> Nkind
(Prag
) = N_Aspect_Specification
);
1212 -- Detect whether the attribute appears within the "Ensures"
1213 -- expression of aspect or pragma Test_Case.
1215 if Present
(Arg
) and then Is_Within
(N
, Arg
) then
1220 ("attribute % must appear in the ensures expression of a "
1223 end Check_Placement_In_Test_Case
;
1231 Encl_Nod
: Node_Id
) return Boolean
1237 while Present
(Par
) loop
1238 if Par
= Encl_Nod
then
1241 -- Prevent the search from going too far
1243 elsif Is_Body_Or_Package_Declaration
(Par
) then
1247 Par
:= Parent
(Par
);
1253 ---------------------
1254 -- Placement_Error --
1255 ---------------------
1257 procedure Placement_Error
is
1259 if Aname
= Name_Old
then
1260 Error_Attr
("attribute % can only appear in postcondition", P
);
1262 -- Specialize the error message for attribute 'Result
1266 ("attribute % can only appear in postcondition of function",
1269 end Placement_Error
;
1275 Subp_Decl
: Node_Id
;
1277 -- Start of processing for Analyze_Attribute_Old_Result
1280 -- Assume that the attribute is illegal
1285 -- Traverse the parent chain to find the aspect or pragma where the
1286 -- attribute resides.
1289 while Present
(Prag
) loop
1290 if Nkind_In
(Prag
, N_Aspect_Specification
, N_Pragma
) then
1293 -- Prevent the search from going too far
1295 elsif Is_Body_Or_Package_Declaration
(Prag
) then
1299 Prag
:= Parent
(Prag
);
1302 -- The attribute is allowed to appear only in postcondition-like
1303 -- aspects or pragmas.
1305 if Nkind_In
(Prag
, N_Aspect_Specification
, N_Pragma
) then
1306 if Nkind
(Prag
) = N_Aspect_Specification
then
1307 Prag_Nam
:= Chars
(Identifier
(Prag
));
1309 Prag_Nam
:= Pragma_Name
(Prag
);
1312 if Prag_Nam
= Name_Check
then
1313 Check_Placement_In_Check
(Prag
);
1315 elsif Prag_Nam
= Name_Contract_Cases
then
1316 Check_Placement_In_Contract_Cases
(Prag
);
1318 -- Attribute 'Result is allowed to appear in aspect or pragma
1319 -- [Refined_]Depends (SPARK RM 6.1.5(11)).
1321 elsif Nam_In
(Prag_Nam
, Name_Depends
, Name_Refined_Depends
)
1322 and then Aname
= Name_Result
1326 elsif Nam_In
(Prag_Nam
, Name_Post
,
1333 elsif Prag_Nam
= Name_Test_Case
then
1334 Check_Placement_In_Test_Case
(Prag
);
1341 -- Otherwise the placement of the attribute is illegal
1348 -- Find the related subprogram subject to the aspect or pragma
1350 if Nkind
(Prag
) = N_Aspect_Specification
then
1351 Subp_Decl
:= Parent
(Prag
);
1353 Subp_Decl
:= Find_Related_Declaration_Or_Body
(Prag
);
1356 -- The aspect or pragma where the attribute resides should be
1357 -- associated with a subprogram declaration or a body. If this is not
1358 -- the case, then the aspect or pragma is illegal. Return as analysis
1359 -- cannot be carried out. Note that it is legal to have the aspect
1360 -- appear on a subprogram renaming, when the renamed entity is an
1361 -- attribute reference.
1363 -- Generating C code the internally built nested _postcondition
1364 -- subprograms are inlined; after expanded, inlined aspects are
1365 -- located in the internal block generated by the frontend.
1367 if Nkind
(Subp_Decl
) = N_Block_Statement
1368 and then Modify_Tree_For_C
1369 and then In_Inlined_Body
1373 elsif not Nkind_In
(Subp_Decl
, N_Abstract_Subprogram_Declaration
,
1374 N_Entry_Declaration
,
1375 N_Expression_Function
,
1376 N_Generic_Subprogram_Declaration
,
1378 N_Subprogram_Body_Stub
,
1379 N_Subprogram_Declaration
,
1380 N_Subprogram_Renaming_Declaration
)
1385 -- If we get here, then the attribute is legal
1388 Spec_Id
:= Unique_Defining_Entity
(Subp_Decl
);
1390 -- When generating C code, nested _postcondition subprograms are
1391 -- inlined by the front end to avoid problems (when unnested) with
1392 -- referenced itypes. Handle that here, since as part of inlining the
1393 -- expander nests subprogram within a dummy procedure named _parent
1394 -- (see Build_Postconditions_Procedure and Build_Body_To_Inline).
1395 -- Hence, in this context, the spec_id of _postconditions is the
1398 if Modify_Tree_For_C
1399 and then Chars
(Spec_Id
) = Name_uParent
1400 and then Chars
(Scope
(Spec_Id
)) = Name_uPostconditions
1402 -- This situation occurs only when preanalyzing the inlined body
1404 pragma Assert
(not Full_Analysis
);
1406 Spec_Id
:= Scope
(Spec_Id
);
1407 pragma Assert
(Is_Inlined
(Spec_Id
));
1409 end Analyze_Attribute_Old_Result
;
1411 -----------------------------
1412 -- Analyze_Image_Attribute --
1413 -----------------------------
1415 procedure Analyze_Image_Attribute
(Str_Typ
: Entity_Id
) is
1417 Check_SPARK_05_Restriction_On_Attribute
;
1419 -- AI12-00124: The ARG has adopted the GNAT semantics of 'Img for
1420 -- scalar types, so that the prefix can be an object, a named value,
1421 -- or a type, and there is no need for an argument in this case.
1423 if Attr_Id
= Attribute_Img
1424 or else (Ada_Version
> Ada_2005
and then Is_Object_Image
(P
))
1427 Set_Etype
(N
, Str_Typ
);
1429 if Attr_Id
= Attribute_Img
and then not Is_Object_Image
(P
) then
1431 ("prefix of % attribute must be a scalar object name");
1435 Set_Etype
(N
, Str_Typ
);
1437 -- Check that the prefix type is scalar - much in the same way as
1438 -- Check_Scalar_Type but with custom error messages to denote the
1439 -- variants of 'Image attributes.
1441 if Is_Entity_Name
(P
)
1442 and then Is_Type
(Entity
(P
))
1443 and then Ekind
(Entity
(P
)) = E_Incomplete_Type
1444 and then Present
(Full_View
(Entity
(P
)))
1446 P_Type
:= Full_View
(Entity
(P
));
1447 Set_Entity
(P
, P_Type
);
1450 if not Is_Entity_Name
(P
)
1451 or else not Is_Type
(Entity
(P
))
1452 or else not Is_Scalar_Type
(P_Type
)
1454 if Ada_Version
> Ada_2005
then
1456 ("prefix of % attribute must be a scalar type or a scalar "
1459 Error_Attr_P
("prefix of % attribute must be a scalar type");
1462 elsif Is_Protected_Self_Reference
(P
) then
1464 ("prefix of % attribute denotes current instance "
1465 & "(RM 9.4(21/2))");
1468 Resolve
(E1
, P_Base_Type
);
1469 Validate_Non_Static_Attribute_Function_Call
;
1474 -- Check restriction No_Fixed_IO. Note the check of Comes_From_Source
1475 -- to avoid giving a duplicate message for when Image attributes
1476 -- applied to object references get expanded into type-based Image
1479 if Restriction_Check_Required
(No_Fixed_IO
)
1480 and then Comes_From_Source
(N
)
1481 and then Is_Fixed_Point_Type
(P_Type
)
1483 Check_Restriction
(No_Fixed_IO
, P
);
1485 end Analyze_Image_Attribute
;
1487 ---------------------------------
1488 -- Bad_Attribute_For_Predicate --
1489 ---------------------------------
1491 procedure Bad_Attribute_For_Predicate
is
1493 if Is_Scalar_Type
(P_Type
)
1494 and then Comes_From_Source
(N
)
1496 Error_Msg_Name_1
:= Aname
;
1497 Bad_Predicated_Subtype_Use
1498 ("type& has predicates, attribute % not allowed", N
, P_Type
);
1500 end Bad_Attribute_For_Predicate
;
1502 --------------------------------
1503 -- Check_Array_Or_Scalar_Type --
1504 --------------------------------
1506 procedure Check_Array_Or_Scalar_Type
is
1507 function In_Aspect_Specification
return Boolean;
1508 -- A current instance of a type in an aspect specification is an
1509 -- object and not a type, and therefore cannot be of a scalar type
1510 -- in the prefix of one of the array attributes if the attribute
1511 -- reference is part of an aspect expression.
1513 -----------------------------
1514 -- In_Aspect_Specification --
1515 -----------------------------
1517 function In_Aspect_Specification
return Boolean is
1522 while Present
(P
) loop
1523 if Nkind
(P
) = N_Aspect_Specification
then
1524 return P_Type
= Entity
(P
);
1526 elsif Nkind
(P
) in N_Declaration
then
1534 end In_Aspect_Specification
;
1541 -- Start of processing for Check_Array_Or_Scalar_Type
1544 -- Case of string literal or string literal subtype. These cases
1545 -- cannot arise from legal Ada code, but the expander is allowed
1546 -- to generate them. They require special handling because string
1547 -- literal subtypes do not have standard bounds (the whole idea
1548 -- of these subtypes is to avoid having to generate the bounds)
1550 if Ekind
(P_Type
) = E_String_Literal_Subtype
then
1551 Set_Etype
(N
, Etype
(First_Index
(P_Base_Type
)));
1556 elsif Is_Scalar_Type
(P_Type
) then
1559 if Present
(E1
) then
1560 Error_Attr
("invalid argument in % attribute", E1
);
1562 elsif In_Aspect_Specification
then
1564 ("prefix of % attribute cannot be the current instance of a "
1565 & "scalar type", P
);
1568 Set_Etype
(N
, P_Base_Type
);
1572 -- The following is a special test to allow 'First to apply to
1573 -- private scalar types if the attribute comes from generated
1574 -- code. This occurs in the case of Normalize_Scalars code.
1576 elsif Is_Private_Type
(P_Type
)
1577 and then Present
(Full_View
(P_Type
))
1578 and then Is_Scalar_Type
(Full_View
(P_Type
))
1579 and then not Comes_From_Source
(N
)
1581 Set_Etype
(N
, Implementation_Base_Type
(P_Type
));
1583 -- Array types other than string literal subtypes handled above
1588 -- We know prefix is an array type, or the name of an array
1589 -- object, and that the expression, if present, is static
1590 -- and within the range of the dimensions of the type.
1592 pragma Assert
(Is_Array_Type
(P_Type
));
1593 Index
:= First_Index
(P_Base_Type
);
1597 -- First dimension assumed
1599 Set_Etype
(N
, Base_Type
(Etype
(Index
)));
1602 Dims
:= UI_To_Int
(Intval
(E1
));
1604 for J
in 1 .. Dims
- 1 loop
1608 Set_Etype
(N
, Base_Type
(Etype
(Index
)));
1609 Set_Etype
(E1
, Standard_Integer
);
1612 end Check_Array_Or_Scalar_Type
;
1614 ----------------------
1615 -- Check_Array_Type --
1616 ----------------------
1618 procedure Check_Array_Type
is
1620 -- Dimension number for array attributes
1623 -- If the type is a string literal type, then this must be generated
1624 -- internally, and no further check is required on its legality.
1626 if Ekind
(P_Type
) = E_String_Literal_Subtype
then
1629 -- If the type is a composite, it is an illegal aggregate, no point
1632 elsif P_Type
= Any_Composite
then
1633 raise Bad_Attribute
;
1636 -- Normal case of array type or subtype
1638 Check_Either_E0_Or_E1
;
1641 if Is_Array_Type
(P_Type
) then
1642 if not Is_Constrained
(P_Type
)
1643 and then Is_Entity_Name
(P
)
1644 and then Is_Type
(Entity
(P
))
1646 -- Note: we do not call Error_Attr here, since we prefer to
1647 -- continue, using the relevant index type of the array,
1648 -- even though it is unconstrained. This gives better error
1649 -- recovery behavior.
1651 Error_Msg_Name_1
:= Aname
;
1653 ("prefix for % attribute must be constrained array", P
);
1656 -- The attribute reference freezes the type, and thus the
1657 -- component type, even if the attribute may not depend on the
1658 -- component. Diagnose arrays with incomplete components now.
1659 -- If the prefix is an access to array, this does not freeze
1660 -- the designated type.
1662 if Nkind
(P
) /= N_Explicit_Dereference
then
1663 Check_Fully_Declared
(Component_Type
(P_Type
), P
);
1666 D
:= Number_Dimensions
(P_Type
);
1669 if Is_Private_Type
(P_Type
) then
1670 Error_Attr_P
("prefix for % attribute may not be private type");
1672 elsif Is_Access_Type
(P_Type
)
1673 and then Is_Array_Type
(Designated_Type
(P_Type
))
1674 and then Is_Entity_Name
(P
)
1675 and then Is_Type
(Entity
(P
))
1677 Error_Attr_P
("prefix of % attribute cannot be access type");
1679 elsif Attr_Id
= Attribute_First
1681 Attr_Id
= Attribute_Last
1683 Error_Attr
("invalid prefix for % attribute", P
);
1686 Error_Attr_P
("prefix for % attribute must be array");
1690 if Present
(E1
) then
1691 Resolve
(E1
, Any_Integer
);
1692 Set_Etype
(E1
, Standard_Integer
);
1694 if not Is_OK_Static_Expression
(E1
)
1695 or else Raises_Constraint_Error
(E1
)
1697 Flag_Non_Static_Expr
1698 ("expression for dimension must be static!", E1
);
1701 elsif UI_To_Int
(Expr_Value
(E1
)) > D
1702 or else UI_To_Int
(Expr_Value
(E1
)) < 1
1704 Error_Attr
("invalid dimension number for array type", E1
);
1708 if (Style_Check
and Style_Check_Array_Attribute_Index
)
1709 and then Comes_From_Source
(N
)
1711 Style
.Check_Array_Attribute_Index
(N
, E1
, D
);
1713 end Check_Array_Type
;
1715 -------------------------
1716 -- Check_Asm_Attribute --
1717 -------------------------
1719 procedure Check_Asm_Attribute
is
1724 -- Check first argument is static string expression
1726 Analyze_And_Resolve
(E1
, Standard_String
);
1728 if Etype
(E1
) = Any_Type
then
1731 elsif not Is_OK_Static_Expression
(E1
) then
1732 Flag_Non_Static_Expr
1733 ("constraint argument must be static string expression!", E1
);
1737 -- Check second argument is right type
1739 Analyze_And_Resolve
(E2
, Entity
(P
));
1741 -- Note: that is all we need to do, we don't need to check
1742 -- that it appears in a correct context. The Ada type system
1743 -- will do that for us.
1745 end Check_Asm_Attribute
;
1747 ---------------------
1748 -- Check_Component --
1749 ---------------------
1751 procedure Check_Component
is
1755 if Nkind
(P
) /= N_Selected_Component
1757 (Ekind
(Entity
(Selector_Name
(P
))) /= E_Component
1759 Ekind
(Entity
(Selector_Name
(P
))) /= E_Discriminant
)
1761 Error_Attr_P
("prefix for % attribute must be selected component");
1763 end Check_Component
;
1765 ------------------------------------
1766 -- Check_Decimal_Fixed_Point_Type --
1767 ------------------------------------
1769 procedure Check_Decimal_Fixed_Point_Type
is
1773 if not Is_Decimal_Fixed_Point_Type
(P_Type
) then
1774 Error_Attr_P
("prefix of % attribute must be decimal type");
1776 end Check_Decimal_Fixed_Point_Type
;
1778 -----------------------
1779 -- Check_Dereference --
1780 -----------------------
1782 procedure Check_Dereference
is
1785 -- Case of a subtype mark
1787 if Is_Entity_Name
(P
) and then Is_Type
(Entity
(P
)) then
1791 -- Case of an expression
1795 if Is_Access_Type
(P_Type
) then
1797 -- If there is an implicit dereference, then we must freeze the
1798 -- designated type of the access type, since the type of the
1799 -- referenced array is this type (see AI95-00106).
1801 -- As done elsewhere, freezing must not happen when pre-analyzing
1802 -- a pre- or postcondition or a default value for an object or for
1803 -- a formal parameter.
1805 if not In_Spec_Expression
then
1806 Freeze_Before
(N
, Designated_Type
(P_Type
));
1810 Make_Explicit_Dereference
(Sloc
(P
),
1811 Prefix
=> Relocate_Node
(P
)));
1813 Analyze_And_Resolve
(P
);
1814 P_Type
:= Etype
(P
);
1816 if P_Type
= Any_Type
then
1817 raise Bad_Attribute
;
1820 P_Base_Type
:= Base_Type
(P_Type
);
1822 end Check_Dereference
;
1824 -------------------------
1825 -- Check_Discrete_Type --
1826 -------------------------
1828 procedure Check_Discrete_Type
is
1832 if not Is_Discrete_Type
(P_Type
) then
1833 Error_Attr_P
("prefix of % attribute must be discrete type");
1835 end Check_Discrete_Type
;
1841 procedure Check_E0
is
1843 if Present
(E1
) then
1844 Unexpected_Argument
(E1
);
1852 procedure Check_E1
is
1854 Check_Either_E0_Or_E1
;
1858 -- Special-case attributes that are functions and that appear as
1859 -- the prefix of another attribute. Error is posted on parent.
1861 if Nkind
(Parent
(N
)) = N_Attribute_Reference
1862 and then Nam_In
(Attribute_Name
(Parent
(N
)), Name_Address
,
1866 Error_Msg_Name_1
:= Attribute_Name
(Parent
(N
));
1867 Error_Msg_N
("illegal prefix for % attribute", Parent
(N
));
1868 Set_Etype
(Parent
(N
), Any_Type
);
1869 Set_Entity
(Parent
(N
), Any_Type
);
1870 raise Bad_Attribute
;
1873 Error_Attr
("missing argument for % attribute", N
);
1882 procedure Check_E2
is
1885 Error_Attr
("missing arguments for % attribute (2 required)", N
);
1887 Error_Attr
("missing argument for % attribute (2 required)", N
);
1891 ---------------------------
1892 -- Check_Either_E0_Or_E1 --
1893 ---------------------------
1895 procedure Check_Either_E0_Or_E1
is
1897 if Present
(E2
) then
1898 Unexpected_Argument
(E2
);
1900 end Check_Either_E0_Or_E1
;
1902 ----------------------
1903 -- Check_Enum_Image --
1904 ----------------------
1906 procedure Check_Enum_Image
is
1910 -- When an enumeration type appears in an attribute reference, all
1911 -- literals of the type are marked as referenced. This must only be
1912 -- done if the attribute reference appears in the current source.
1913 -- Otherwise the information on references may differ between a
1914 -- normal compilation and one that performs inlining.
1916 if Is_Enumeration_Type
(P_Base_Type
)
1917 and then In_Extended_Main_Code_Unit
(N
)
1919 Lit
:= First_Literal
(P_Base_Type
);
1920 while Present
(Lit
) loop
1921 Set_Referenced
(Lit
);
1925 end Check_Enum_Image
;
1927 ----------------------------
1928 -- Check_First_Last_Valid --
1929 ----------------------------
1931 procedure Check_First_Last_Valid
is
1933 Check_Discrete_Type
;
1935 -- Freeze the subtype now, so that the following test for predicates
1936 -- works (we set the predicates stuff up at freeze time)
1938 Insert_Actions
(N
, Freeze_Entity
(P_Type
, P
));
1940 -- Now test for dynamic predicate
1942 if Has_Predicates
(P_Type
)
1943 and then not (Has_Static_Predicate
(P_Type
))
1946 ("prefix of % attribute may not have dynamic predicate");
1949 -- Check non-static subtype
1951 if not Is_OK_Static_Subtype
(P_Type
) then
1952 Error_Attr_P
("prefix of % attribute must be a static subtype");
1955 -- Test case for no values
1957 if Expr_Value
(Type_Low_Bound
(P_Type
)) >
1958 Expr_Value
(Type_High_Bound
(P_Type
))
1959 or else (Has_Predicates
(P_Type
)
1961 Is_Empty_List
(Static_Discrete_Predicate
(P_Type
)))
1964 ("prefix of % attribute must be subtype with at least one "
1967 end Check_First_Last_Valid
;
1969 ----------------------------
1970 -- Check_Fixed_Point_Type --
1971 ----------------------------
1973 procedure Check_Fixed_Point_Type
is
1977 if not Is_Fixed_Point_Type
(P_Type
) then
1978 Error_Attr_P
("prefix of % attribute must be fixed point type");
1980 end Check_Fixed_Point_Type
;
1982 ------------------------------
1983 -- Check_Fixed_Point_Type_0 --
1984 ------------------------------
1986 procedure Check_Fixed_Point_Type_0
is
1988 Check_Fixed_Point_Type
;
1990 end Check_Fixed_Point_Type_0
;
1992 -------------------------------
1993 -- Check_Floating_Point_Type --
1994 -------------------------------
1996 procedure Check_Floating_Point_Type
is
2000 if not Is_Floating_Point_Type
(P_Type
) then
2001 Error_Attr_P
("prefix of % attribute must be float type");
2003 end Check_Floating_Point_Type
;
2005 ---------------------------------
2006 -- Check_Floating_Point_Type_0 --
2007 ---------------------------------
2009 procedure Check_Floating_Point_Type_0
is
2011 Check_Floating_Point_Type
;
2013 end Check_Floating_Point_Type_0
;
2015 ---------------------------------
2016 -- Check_Floating_Point_Type_1 --
2017 ---------------------------------
2019 procedure Check_Floating_Point_Type_1
is
2021 Check_Floating_Point_Type
;
2023 end Check_Floating_Point_Type_1
;
2025 ---------------------------------
2026 -- Check_Floating_Point_Type_2 --
2027 ---------------------------------
2029 procedure Check_Floating_Point_Type_2
is
2031 Check_Floating_Point_Type
;
2033 end Check_Floating_Point_Type_2
;
2035 ------------------------
2036 -- Check_Integer_Type --
2037 ------------------------
2039 procedure Check_Integer_Type
is
2043 if not Is_Integer_Type
(P_Type
) then
2044 Error_Attr_P
("prefix of % attribute must be integer type");
2046 end Check_Integer_Type
;
2048 --------------------------------
2049 -- Check_Modular_Integer_Type --
2050 --------------------------------
2052 procedure Check_Modular_Integer_Type
is
2056 if not Is_Modular_Integer_Type
(P_Type
) then
2058 ("prefix of % attribute must be modular integer type");
2060 end Check_Modular_Integer_Type
;
2062 ------------------------
2063 -- Check_Not_CPP_Type --
2064 ------------------------
2066 procedure Check_Not_CPP_Type
is
2068 if Is_Tagged_Type
(Etype
(P
))
2069 and then Convention
(Etype
(P
)) = Convention_CPP
2070 and then Is_CPP_Class
(Root_Type
(Etype
(P
)))
2073 ("invalid use of % attribute with 'C'P'P tagged type");
2075 end Check_Not_CPP_Type
;
2077 -------------------------------
2078 -- Check_Not_Incomplete_Type --
2079 -------------------------------
2081 procedure Check_Not_Incomplete_Type
is
2086 -- Ada 2005 (AI-50217, AI-326): If the prefix is an explicit
2087 -- dereference we have to check wrong uses of incomplete types
2088 -- (other wrong uses are checked at their freezing point).
2090 -- In Ada 2012, incomplete types can appear in subprogram
2091 -- profiles, but formals with incomplete types cannot be the
2092 -- prefix of attributes.
2094 -- Example 1: Limited-with
2096 -- limited with Pkg;
2098 -- type Acc is access Pkg.T;
2100 -- S : Integer := X.all'Size; -- ERROR
2103 -- Example 2: Tagged incomplete
2105 -- type T is tagged;
2106 -- type Acc is access all T;
2108 -- S : constant Integer := X.all'Size; -- ERROR
2109 -- procedure Q (Obj : Integer := X.all'Alignment); -- ERROR
2111 if Ada_Version
>= Ada_2005
2112 and then Nkind
(P
) = N_Explicit_Dereference
2115 while Nkind
(E
) = N_Explicit_Dereference
loop
2121 if From_Limited_With
(Typ
) then
2123 ("prefix of % attribute cannot be an incomplete type");
2125 -- If the prefix is an access type check the designated type
2127 elsif Is_Access_Type
(Typ
)
2128 and then Nkind
(P
) = N_Explicit_Dereference
2130 Typ
:= Directly_Designated_Type
(Typ
);
2133 if Is_Class_Wide_Type
(Typ
) then
2134 Typ
:= Root_Type
(Typ
);
2137 -- A legal use of a shadow entity occurs only when the unit where
2138 -- the non-limited view resides is imported via a regular with
2139 -- clause in the current body. Such references to shadow entities
2140 -- may occur in subprogram formals.
2142 if Is_Incomplete_Type
(Typ
)
2143 and then From_Limited_With
(Typ
)
2144 and then Present
(Non_Limited_View
(Typ
))
2145 and then Is_Legal_Shadow_Entity_In_Body
(Typ
)
2147 Typ
:= Non_Limited_View
(Typ
);
2150 -- If still incomplete, it can be a local incomplete type, or a
2151 -- limited view whose scope is also a limited view.
2153 if Ekind
(Typ
) = E_Incomplete_Type
then
2154 if not From_Limited_With
(Typ
)
2155 and then No
(Full_View
(Typ
))
2158 ("prefix of % attribute cannot be an incomplete type");
2160 -- The limited view may be available indirectly through
2161 -- an intermediate unit. If the non-limited view is available
2162 -- the attribute reference is legal.
2164 elsif From_Limited_With
(Typ
)
2166 (No
(Non_Limited_View
(Typ
))
2167 or else Is_Incomplete_Type
(Non_Limited_View
(Typ
)))
2170 ("prefix of % attribute cannot be an incomplete type");
2174 -- Ada 2012 : formals in bodies may be incomplete, but no attribute
2177 elsif Is_Entity_Name
(P
)
2178 and then Is_Formal
(Entity
(P
))
2179 and then Is_Incomplete_Type
(Etype
(Etype
(P
)))
2182 ("prefix of % attribute cannot be an incomplete type");
2185 if not Is_Entity_Name
(P
)
2186 or else not Is_Type
(Entity
(P
))
2187 or else In_Spec_Expression
2191 Check_Fully_Declared
(P_Type
, P
);
2193 end Check_Not_Incomplete_Type
;
2195 ----------------------------
2196 -- Check_Object_Reference --
2197 ----------------------------
2199 procedure Check_Object_Reference
(P
: Node_Id
) is
2203 -- If we need an object, and we have a prefix that is the name of
2204 -- a function entity, convert it into a function call.
2206 if Is_Entity_Name
(P
)
2207 and then Ekind
(Entity
(P
)) = E_Function
2209 Rtyp
:= Etype
(Entity
(P
));
2212 Make_Function_Call
(Sloc
(P
),
2213 Name
=> Relocate_Node
(P
)));
2215 Analyze_And_Resolve
(P
, Rtyp
);
2217 -- Otherwise we must have an object reference
2219 elsif not Is_Object_Reference
(P
) then
2220 Error_Attr_P
("prefix of % attribute must be object");
2222 end Check_Object_Reference
;
2224 ----------------------------
2225 -- Check_PolyORB_Attribute --
2226 ----------------------------
2228 procedure Check_PolyORB_Attribute
is
2230 Validate_Non_Static_Attribute_Function_Call
;
2235 if Get_PCS_Name
/= Name_PolyORB_DSA
then
2237 ("attribute% requires the 'Poly'O'R'B 'P'C'S", N
);
2239 end Check_PolyORB_Attribute
;
2241 ------------------------
2242 -- Check_Program_Unit --
2243 ------------------------
2245 procedure Check_Program_Unit
is
2247 if Is_Entity_Name
(P
) then
2249 K
: constant Entity_Kind
:= Ekind
(Entity
(P
));
2250 T
: constant Entity_Id
:= Etype
(Entity
(P
));
2253 if K
in Subprogram_Kind
2254 or else K
in Task_Kind
2255 or else K
in Protected_Kind
2256 or else K
= E_Package
2257 or else K
in Generic_Unit_Kind
2258 or else (K
= E_Variable
2262 Is_Protected_Type
(T
)))
2269 Error_Attr_P
("prefix of % attribute must be program unit");
2270 end Check_Program_Unit
;
2272 ---------------------
2273 -- Check_Real_Type --
2274 ---------------------
2276 procedure Check_Real_Type
is
2280 if not Is_Real_Type
(P_Type
) then
2281 Error_Attr_P
("prefix of % attribute must be real type");
2283 end Check_Real_Type
;
2285 -----------------------
2286 -- Check_Scalar_Type --
2287 -----------------------
2289 procedure Check_Scalar_Type
is
2293 if not Is_Scalar_Type
(P_Type
) then
2294 Error_Attr_P
("prefix of % attribute must be scalar type");
2296 end Check_Scalar_Type
;
2298 ------------------------------------------
2299 -- Check_SPARK_05_Restriction_On_Attribute --
2300 ------------------------------------------
2302 procedure Check_SPARK_05_Restriction_On_Attribute
is
2304 Error_Msg_Name_1
:= Aname
;
2305 Check_SPARK_05_Restriction
("attribute % is not allowed", P
);
2306 end Check_SPARK_05_Restriction_On_Attribute
;
2308 ---------------------------
2309 -- Check_Standard_Prefix --
2310 ---------------------------
2312 procedure Check_Standard_Prefix
is
2316 if Nkind
(P
) /= N_Identifier
or else Chars
(P
) /= Name_Standard
then
2317 Error_Attr
("only allowed prefix for % attribute is Standard", P
);
2319 end Check_Standard_Prefix
;
2321 ----------------------------
2322 -- Check_Stream_Attribute --
2323 ----------------------------
2325 procedure Check_Stream_Attribute
(Nam
: TSS_Name_Type
) is
2329 In_Shared_Var_Procs
: Boolean;
2330 -- True when compiling System.Shared_Storage.Shared_Var_Procs body.
2331 -- For this runtime package (always compiled in GNAT mode), we allow
2332 -- stream attributes references for limited types for the case where
2333 -- shared passive objects are implemented using stream attributes,
2334 -- which is the default in GNAT's persistent storage implementation.
2337 Validate_Non_Static_Attribute_Function_Call
;
2339 -- With the exception of 'Input, Stream attributes are procedures,
2340 -- and can only appear at the position of procedure calls. We check
2341 -- for this here, before they are rewritten, to give a more precise
2344 if Nam
= TSS_Stream_Input
then
2347 elsif Is_List_Member
(N
)
2348 and then not Nkind_In
(Parent
(N
), N_Procedure_Call_Statement
,
2355 ("invalid context for attribute%, which is a procedure", N
);
2359 Btyp
:= Implementation_Base_Type
(P_Type
);
2361 -- Stream attributes not allowed on limited types unless the
2362 -- attribute reference was generated by the expander (in which
2363 -- case the underlying type will be used, as described in Sinfo),
2364 -- or the attribute was specified explicitly for the type itself
2365 -- or one of its ancestors (taking visibility rules into account if
2366 -- in Ada 2005 mode), or a pragma Stream_Convert applies to Btyp
2367 -- (with no visibility restriction).
2370 Gen_Body
: constant Node_Id
:= Enclosing_Generic_Body
(N
);
2372 if Present
(Gen_Body
) then
2373 In_Shared_Var_Procs
:=
2374 Is_RTE
(Corresponding_Spec
(Gen_Body
), RE_Shared_Var_Procs
);
2376 In_Shared_Var_Procs
:= False;
2380 if (Comes_From_Source
(N
)
2381 and then not (In_Shared_Var_Procs
or In_Instance
))
2382 and then not Stream_Attribute_Available
(P_Type
, Nam
)
2383 and then not Has_Rep_Pragma
(Btyp
, Name_Stream_Convert
)
2385 Error_Msg_Name_1
:= Aname
;
2387 if Is_Limited_Type
(P_Type
) then
2389 ("limited type& has no% attribute", P
, P_Type
);
2390 Explain_Limited_Type
(P_Type
, P
);
2393 ("attribute% for type& is not available", P
, P_Type
);
2397 -- Check for no stream operations allowed from No_Tagged_Streams
2399 if Is_Tagged_Type
(P_Type
)
2400 and then Present
(No_Tagged_Streams_Pragma
(P_Type
))
2402 Error_Msg_Sloc
:= Sloc
(No_Tagged_Streams_Pragma
(P_Type
));
2404 ("no stream operations for & (No_Tagged_Streams #)", N
, P_Type
);
2408 -- Check restriction violations
2410 -- First check the No_Streams restriction, which prohibits the use
2411 -- of explicit stream attributes in the source program. We do not
2412 -- prevent the occurrence of stream attributes in generated code,
2413 -- for instance those generated implicitly for dispatching purposes.
2415 if Comes_From_Source
(N
) then
2416 Check_Restriction
(No_Streams
, P
);
2419 -- AI05-0057: if restriction No_Default_Stream_Attributes is active,
2420 -- it is illegal to use a predefined elementary type stream attribute
2421 -- either by itself, or more importantly as part of the attribute
2422 -- subprogram for a composite type. However, if the broader
2423 -- restriction No_Streams is active, stream operations are not
2424 -- generated, and there is no error.
2426 if Restriction_Active
(No_Default_Stream_Attributes
)
2427 and then not Restriction_Active
(No_Streams
)
2433 if Nam
= TSS_Stream_Input
2435 Nam
= TSS_Stream_Read
2438 Type_Without_Stream_Operation
(P_Type
, TSS_Stream_Read
);
2441 Type_Without_Stream_Operation
(P_Type
, TSS_Stream_Write
);
2445 Check_Restriction
(No_Default_Stream_Attributes
, N
);
2448 ("missing user-defined Stream Read or Write for type&",
2450 if not Is_Elementary_Type
(P_Type
) then
2452 ("\which is a component of type&", N
, P_Type
);
2458 -- Check special case of Exception_Id and Exception_Occurrence which
2459 -- are not allowed for restriction No_Exception_Registration.
2461 if Restriction_Check_Required
(No_Exception_Registration
)
2462 and then (Is_RTE
(P_Type
, RE_Exception_Id
)
2464 Is_RTE
(P_Type
, RE_Exception_Occurrence
))
2466 Check_Restriction
(No_Exception_Registration
, P
);
2469 -- Here we must check that the first argument is an access type
2470 -- that is compatible with Ada.Streams.Root_Stream_Type'Class.
2472 Analyze_And_Resolve
(E1
);
2475 -- Note: the double call to Root_Type here is needed because the
2476 -- root type of a class-wide type is the corresponding type (e.g.
2477 -- X for X'Class, and we really want to go to the root.)
2479 if not Is_Access_Type
(Etyp
)
2480 or else Root_Type
(Root_Type
(Designated_Type
(Etyp
))) /=
2481 RTE
(RE_Root_Stream_Type
)
2484 ("expected access to Ada.Streams.Root_Stream_Type''Class", E1
);
2487 -- Check that the second argument is of the right type if there is
2488 -- one (the Input attribute has only one argument so this is skipped)
2490 if Present
(E2
) then
2493 if Nam
= TSS_Stream_Read
2494 and then not Is_OK_Variable_For_Out_Formal
(E2
)
2497 ("second argument of % attribute must be a variable", E2
);
2500 Resolve
(E2
, P_Type
);
2504 end Check_Stream_Attribute
;
2506 -------------------------
2507 -- Check_System_Prefix --
2508 -------------------------
2510 procedure Check_System_Prefix
is
2512 if Nkind
(P
) /= N_Identifier
or else Chars
(P
) /= Name_System
then
2513 Error_Attr
("only allowed prefix for % attribute is System", P
);
2515 end Check_System_Prefix
;
2517 -----------------------
2518 -- Check_Task_Prefix --
2519 -----------------------
2521 procedure Check_Task_Prefix
is
2525 -- Ada 2005 (AI-345): Attribute 'Terminated can be applied to
2526 -- task interface class-wide types.
2528 if Is_Task_Type
(Etype
(P
))
2529 or else (Is_Access_Type
(Etype
(P
))
2530 and then Is_Task_Type
(Designated_Type
(Etype
(P
))))
2531 or else (Ada_Version
>= Ada_2005
2532 and then Ekind
(Etype
(P
)) = E_Class_Wide_Type
2533 and then Is_Interface
(Etype
(P
))
2534 and then Is_Task_Interface
(Etype
(P
)))
2539 if Ada_Version
>= Ada_2005
then
2541 ("prefix of % attribute must be a task or a task " &
2542 "interface class-wide object");
2545 Error_Attr_P
("prefix of % attribute must be a task");
2548 end Check_Task_Prefix
;
2554 -- The possibilities are an entity name denoting a type, or an
2555 -- attribute reference that denotes a type (Base or Class). If
2556 -- the type is incomplete, replace it with its full view.
2558 procedure Check_Type
is
2560 if not Is_Entity_Name
(P
)
2561 or else not Is_Type
(Entity
(P
))
2563 Error_Attr_P
("prefix of % attribute must be a type");
2565 elsif Is_Protected_Self_Reference
(P
) then
2567 ("prefix of % attribute denotes current instance "
2568 & "(RM 9.4(21/2))");
2570 elsif Ekind
(Entity
(P
)) = E_Incomplete_Type
2571 and then Present
(Full_View
(Entity
(P
)))
2573 P_Type
:= Full_View
(Entity
(P
));
2574 Set_Entity
(P
, P_Type
);
2578 ---------------------
2579 -- Check_Unit_Name --
2580 ---------------------
2582 procedure Check_Unit_Name
(Nod
: Node_Id
) is
2584 if Nkind
(Nod
) = N_Identifier
then
2587 elsif Nkind_In
(Nod
, N_Selected_Component
, N_Expanded_Name
) then
2588 Check_Unit_Name
(Prefix
(Nod
));
2590 if Nkind
(Selector_Name
(Nod
)) = N_Identifier
then
2595 Error_Attr
("argument for % attribute must be unit name", P
);
2596 end Check_Unit_Name
;
2602 procedure Error_Attr
is
2604 Set_Etype
(N
, Any_Type
);
2605 Set_Entity
(N
, Any_Type
);
2606 raise Bad_Attribute
;
2609 procedure Error_Attr
(Msg
: String; Error_Node
: Node_Id
) is
2611 Error_Msg_Name_1
:= Aname
;
2612 Error_Msg_N
(Msg
, Error_Node
);
2620 procedure Error_Attr_P
(Msg
: String) is
2622 Error_Msg_Name_1
:= Aname
;
2623 Error_Msg_F
(Msg
, P
);
2627 ----------------------------
2628 -- Legal_Formal_Attribute --
2629 ----------------------------
2631 procedure Legal_Formal_Attribute
is
2635 if not Is_Entity_Name
(P
)
2636 or else not Is_Type
(Entity
(P
))
2638 Error_Attr_P
("prefix of % attribute must be generic type");
2640 elsif Is_Generic_Actual_Type
(Entity
(P
))
2642 or else In_Inlined_Body
2646 elsif Is_Generic_Type
(Entity
(P
)) then
2647 if Is_Definite_Subtype
(Entity
(P
)) then
2649 ("prefix of % attribute must be indefinite generic type");
2654 ("prefix of % attribute must be indefinite generic type");
2657 Set_Etype
(N
, Standard_Boolean
);
2658 end Legal_Formal_Attribute
;
2660 ---------------------------------------------------------------
2661 -- Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements --
2662 ---------------------------------------------------------------
2664 procedure Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
is
2668 Check_Not_Incomplete_Type
;
2669 Set_Etype
(N
, Universal_Integer
);
2670 end Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
;
2676 procedure Min_Max
is
2680 Resolve
(E1
, P_Base_Type
);
2681 Resolve
(E2
, P_Base_Type
);
2682 Set_Etype
(N
, P_Base_Type
);
2684 -- Check for comparison on unordered enumeration type
2686 if Bad_Unordered_Enumeration_Reference
(N
, P_Base_Type
) then
2687 Error_Msg_Sloc
:= Sloc
(P_Base_Type
);
2689 ("comparison on unordered enumeration type& declared#?U?",
2694 ------------------------
2695 -- Standard_Attribute --
2696 ------------------------
2698 procedure Standard_Attribute
(Val
: Int
) is
2700 Check_Standard_Prefix
;
2701 Rewrite
(N
, Make_Integer_Literal
(Loc
, Val
));
2703 Set_Is_Static_Expression
(N
, True);
2704 end Standard_Attribute
;
2706 --------------------
2707 -- Uneval_Old_Msg --
2708 --------------------
2710 procedure Uneval_Old_Msg
is
2711 Uneval_Old_Setting
: Character;
2715 -- If from aspect, then Uneval_Old_Setting comes from flags in the
2716 -- N_Aspect_Specification node that corresponds to the attribute.
2718 -- First find the pragma in which we appear (note that at this stage,
2719 -- even if we appeared originally within an aspect specification, we
2720 -- are now within the corresponding pragma).
2724 Prag
:= Parent
(Prag
);
2725 exit when No
(Prag
) or else Nkind
(Prag
) = N_Pragma
;
2728 if Present
(Prag
) then
2729 if Uneval_Old_Accept
(Prag
) then
2730 Uneval_Old_Setting
:= 'A';
2731 elsif Uneval_Old_Warn
(Prag
) then
2732 Uneval_Old_Setting
:= 'W';
2734 Uneval_Old_Setting
:= 'E';
2737 -- If we did not find the pragma, that's odd, just use the setting
2738 -- from Opt.Uneval_Old. Perhaps this is due to a previous error?
2741 Uneval_Old_Setting
:= Opt
.Uneval_Old
;
2744 -- Processing depends on the setting of Uneval_Old
2746 case Uneval_Old_Setting
is
2749 ("prefix of attribute % that is potentially "
2750 & "unevaluated must denote an entity");
2753 Error_Msg_Name_1
:= Aname
;
2755 ("??prefix of attribute % appears in potentially "
2756 & "unevaluated context, exception may be raised", P
);
2762 raise Program_Error
;
2766 -------------------------
2767 -- Unexpected Argument --
2768 -------------------------
2770 procedure Unexpected_Argument
(En
: Node_Id
) is
2772 Error_Attr
("unexpected argument for % attribute", En
);
2773 end Unexpected_Argument
;
2775 -------------------------------------------------
2776 -- Validate_Non_Static_Attribute_Function_Call --
2777 -------------------------------------------------
2779 -- This function should be moved to Sem_Dist ???
2781 procedure Validate_Non_Static_Attribute_Function_Call
is
2783 if In_Preelaborated_Unit
2784 and then not In_Subprogram_Or_Concurrent_Unit
2786 Flag_Non_Static_Expr
2787 ("non-static function call in preelaborated unit!", N
);
2789 end Validate_Non_Static_Attribute_Function_Call
;
2791 -- Start of processing for Analyze_Attribute
2794 -- Immediate return if unrecognized attribute (already diagnosed by
2795 -- parser, so there is nothing more that we need to do).
2797 if not Is_Attribute_Name
(Aname
) then
2798 raise Bad_Attribute
;
2801 Check_Restriction_No_Use_Of_Attribute
(N
);
2803 -- Deal with Ada 83 issues
2805 if Comes_From_Source
(N
) then
2806 if not Attribute_83
(Attr_Id
) then
2807 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
2808 Error_Msg_Name_1
:= Aname
;
2809 Error_Msg_N
("(Ada 83) attribute% is not standard??", N
);
2812 if Attribute_Impl_Def
(Attr_Id
) then
2813 Check_Restriction
(No_Implementation_Attributes
, N
);
2818 -- Deal with Ada 2005 attributes that are implementation attributes
2819 -- because they appear in a version of Ada before Ada 2005, and
2820 -- similarly for Ada 2012 attributes appearing in an earlier version.
2822 if (Attribute_05
(Attr_Id
) and then Ada_Version
< Ada_2005
)
2824 (Attribute_12
(Attr_Id
) and then Ada_Version
< Ada_2012
)
2826 Check_Restriction
(No_Implementation_Attributes
, N
);
2829 -- Remote access to subprogram type access attribute reference needs
2830 -- unanalyzed copy for tree transformation. The analyzed copy is used
2831 -- for its semantic information (whether prefix is a remote subprogram
2832 -- name), the unanalyzed copy is used to construct new subtree rooted
2833 -- with N_Aggregate which represents a fat pointer aggregate.
2835 if Aname
= Name_Access
then
2836 Discard_Node
(Copy_Separate_Tree
(N
));
2839 -- Analyze prefix and exit if error in analysis. If the prefix is an
2840 -- incomplete type, use full view if available. Note that there are
2841 -- some attributes for which we do not analyze the prefix, since the
2842 -- prefix is not a normal name, or else needs special handling.
2844 if Aname
/= Name_Elab_Body
and then
2845 Aname
/= Name_Elab_Spec
and then
2846 Aname
/= Name_Elab_Subp_Body
and then
2847 Aname
/= Name_Enabled
and then
2851 P_Type
:= Etype
(P
);
2853 if Is_Entity_Name
(P
)
2854 and then Present
(Entity
(P
))
2855 and then Is_Type
(Entity
(P
))
2857 if Ekind
(Entity
(P
)) = E_Incomplete_Type
then
2858 P_Type
:= Get_Full_View
(P_Type
);
2859 Set_Entity
(P
, P_Type
);
2860 Set_Etype
(P
, P_Type
);
2862 elsif Entity
(P
) = Current_Scope
2863 and then Is_Record_Type
(Entity
(P
))
2865 -- Use of current instance within the type. Verify that if the
2866 -- attribute appears within a constraint, it yields an access
2867 -- type, other uses are illegal.
2875 and then Nkind
(Parent
(Par
)) /= N_Component_Definition
2877 Par
:= Parent
(Par
);
2881 and then Nkind
(Par
) = N_Subtype_Indication
2883 if Attr_Id
/= Attribute_Access
2884 and then Attr_Id
/= Attribute_Unchecked_Access
2885 and then Attr_Id
/= Attribute_Unrestricted_Access
2888 ("in a constraint the current instance can only "
2889 & "be used with an access attribute", N
);
2896 if P_Type
= Any_Type
then
2897 raise Bad_Attribute
;
2900 P_Base_Type
:= Base_Type
(P_Type
);
2903 -- Analyze expressions that may be present, exiting if an error occurs
2910 E1
:= First
(Exprs
);
2912 -- Skip analysis for case of Restriction_Set, we do not expect
2913 -- the argument to be analyzed in this case.
2915 if Aname
/= Name_Restriction_Set
then
2918 -- Check for missing/bad expression (result of previous error)
2920 if No
(E1
) or else Etype
(E1
) = Any_Type
then
2921 raise Bad_Attribute
;
2927 if Present
(E2
) then
2930 if Etype
(E2
) = Any_Type
then
2931 raise Bad_Attribute
;
2934 if Present
(Next
(E2
)) then
2935 Unexpected_Argument
(Next
(E2
));
2940 -- Cases where prefix must be resolvable by itself
2942 if Is_Overloaded
(P
)
2943 and then Aname
/= Name_Access
2944 and then Aname
/= Name_Address
2945 and then Aname
/= Name_Code_Address
2946 and then Aname
/= Name_Result
2947 and then Aname
/= Name_Unchecked_Access
2949 -- The prefix must be resolvable by itself, without reference to the
2950 -- attribute. One case that requires special handling is a prefix
2951 -- that is a function name, where one interpretation may be a
2952 -- parameterless call. Entry attributes are handled specially below.
2954 if Is_Entity_Name
(P
)
2955 and then not Nam_In
(Aname
, Name_Count
, Name_Caller
)
2957 Check_Parameterless_Call
(P
);
2960 if Is_Overloaded
(P
) then
2962 -- Ada 2005 (AI-345): Since protected and task types have
2963 -- primitive entry wrappers, the attributes Count, and Caller
2964 -- require a context check
2966 if Nam_In
(Aname
, Name_Count
, Name_Caller
) then
2968 Count
: Natural := 0;
2973 Get_First_Interp
(P
, I
, It
);
2974 while Present
(It
.Nam
) loop
2975 if Comes_From_Source
(It
.Nam
) then
2981 Get_Next_Interp
(I
, It
);
2985 Error_Attr
("ambiguous prefix for % attribute", P
);
2987 Set_Is_Overloaded
(P
, False);
2992 Error_Attr
("ambiguous prefix for % attribute", P
);
2997 -- In SPARK, attributes of private types are only allowed if the full
2998 -- type declaration is visible.
3000 -- Note: the check for Present (Entity (P)) defends against some error
3001 -- conditions where the Entity field is not set.
3003 if Is_Entity_Name
(P
) and then Present
(Entity
(P
))
3004 and then Is_Type
(Entity
(P
))
3005 and then Is_Private_Type
(P_Type
)
3006 and then not In_Open_Scopes
(Scope
(P_Type
))
3007 and then not In_Spec_Expression
3009 Check_SPARK_05_Restriction
("invisible attribute of type", N
);
3012 -- Remaining processing depends on attribute
3016 -- Attributes related to Ada 2012 iterators. Attribute specifications
3017 -- exist for these, but they cannot be queried.
3019 when Attribute_Constant_Indexing
3020 | Attribute_Default_Iterator
3021 | Attribute_Implicit_Dereference
3022 | Attribute_Iterator_Element
3023 | Attribute_Iterable
3024 | Attribute_Variable_Indexing
3026 Error_Msg_N
("illegal attribute", N
);
3028 -- Internal attributes used to deal with Ada 2012 delayed aspects. These
3029 -- were already rejected by the parser. Thus they shouldn't appear here.
3031 when Internal_Attribute_Id
=>
3032 raise Program_Error
;
3038 when Attribute_Abort_Signal
=>
3039 Check_Standard_Prefix
;
3040 Rewrite
(N
, New_Occurrence_Of
(Stand
.Abort_Signal
, Loc
));
3047 when Attribute_Access
=>
3048 Analyze_Access_Attribute
;
3049 Check_Not_Incomplete_Type
;
3055 when Attribute_Address
=>
3058 Check_Not_Incomplete_Type
;
3059 Set_Etype
(N
, RTE
(RE_Address
));
3065 when Attribute_Address_Size
=>
3066 Standard_Attribute
(System_Address_Size
);
3072 when Attribute_Adjacent
=>
3073 Check_Floating_Point_Type_2
;
3074 Set_Etype
(N
, P_Base_Type
);
3075 Resolve
(E1
, P_Base_Type
);
3076 Resolve
(E2
, P_Base_Type
);
3082 when Attribute_Aft
=>
3083 Check_Fixed_Point_Type_0
;
3084 Set_Etype
(N
, Universal_Integer
);
3090 when Attribute_Alignment
=>
3092 -- Don't we need more checking here, cf Size ???
3095 Check_Not_Incomplete_Type
;
3097 Set_Etype
(N
, Universal_Integer
);
3103 when Attribute_Asm_Input
=>
3104 Check_Asm_Attribute
;
3106 -- The back end may need to take the address of E2
3108 if Is_Entity_Name
(E2
) then
3109 Set_Address_Taken
(Entity
(E2
));
3112 Set_Etype
(N
, RTE
(RE_Asm_Input_Operand
));
3118 when Attribute_Asm_Output
=>
3119 Check_Asm_Attribute
;
3121 if Etype
(E2
) = Any_Type
then
3124 elsif Aname
= Name_Asm_Output
then
3125 if not Is_Variable
(E2
) then
3127 ("second argument for Asm_Output is not variable", E2
);
3131 Note_Possible_Modification
(E2
, Sure
=> True);
3133 -- The back end may need to take the address of E2
3135 if Is_Entity_Name
(E2
) then
3136 Set_Address_Taken
(Entity
(E2
));
3139 Set_Etype
(N
, RTE
(RE_Asm_Output_Operand
));
3141 -----------------------------
3142 -- Atomic_Always_Lock_Free --
3143 -----------------------------
3145 when Attribute_Atomic_Always_Lock_Free
=>
3148 Set_Etype
(N
, Standard_Boolean
);
3154 -- Note: when the base attribute appears in the context of a subtype
3155 -- mark, the analysis is done by Sem_Ch8.Find_Type, rather than by
3156 -- the following circuit.
3158 when Attribute_Base
=> Base
: declare
3166 if Ada_Version
>= Ada_95
3167 and then not Is_Scalar_Type
(Typ
)
3168 and then not Is_Generic_Type
(Typ
)
3170 Error_Attr_P
("prefix of Base attribute must be scalar type");
3172 elsif Sloc
(Typ
) = Standard_Location
3173 and then Base_Type
(Typ
) = Typ
3174 and then Warn_On_Redundant_Constructs
3176 Error_Msg_NE
-- CODEFIX
3177 ("?r?redundant attribute, & is its own base type", N
, Typ
);
3180 if Nkind
(Parent
(N
)) /= N_Attribute_Reference
then
3181 Error_Msg_Name_1
:= Aname
;
3182 Check_SPARK_05_Restriction
3183 ("attribute% is only allowed as prefix of another attribute", P
);
3186 Set_Etype
(N
, Base_Type
(Entity
(P
)));
3187 Set_Entity
(N
, Base_Type
(Entity
(P
)));
3188 Rewrite
(N
, New_Occurrence_Of
(Entity
(N
), Loc
));
3196 when Attribute_Bit
=>
3199 if not Is_Object_Reference
(P
) then
3200 Error_Attr_P
("prefix for % attribute must be object");
3202 -- What about the access object cases ???
3208 Set_Etype
(N
, Universal_Integer
);
3214 when Attribute_Bit_Order
=>
3218 if not Is_Record_Type
(P_Type
) then
3219 Error_Attr_P
("prefix of % attribute must be record type");
3222 if Bytes_Big_Endian
xor Reverse_Bit_Order
(P_Type
) then
3224 New_Occurrence_Of
(RTE
(RE_High_Order_First
), Loc
));
3227 New_Occurrence_Of
(RTE
(RE_Low_Order_First
), Loc
));
3230 Set_Etype
(N
, RTE
(RE_Bit_Order
));
3233 -- Reset incorrect indication of staticness
3235 Set_Is_Static_Expression
(N
, False);
3241 -- Note: in generated code, we can have a Bit_Position attribute
3242 -- applied to a (naked) record component (i.e. the prefix is an
3243 -- identifier that references an E_Component or E_Discriminant
3244 -- entity directly, and this is interpreted as expected by Gigi.
3245 -- The following code will not tolerate such usage, but when the
3246 -- expander creates this special case, it marks it as analyzed
3247 -- immediately and sets an appropriate type.
3249 when Attribute_Bit_Position
=>
3250 if Comes_From_Source
(N
) then
3254 Set_Etype
(N
, Universal_Integer
);
3260 when Attribute_Body_Version
=>
3263 Set_Etype
(N
, RTE
(RE_Version_String
));
3269 when Attribute_Callable
=>
3271 Set_Etype
(N
, Standard_Boolean
);
3278 when Attribute_Caller
=> Caller
: declare
3285 if Nkind_In
(P
, N_Identifier
, N_Expanded_Name
) then
3288 if not Is_Entry
(Ent
) then
3289 Error_Attr
("invalid entry name", N
);
3293 Error_Attr
("invalid entry name", N
);
3297 for J
in reverse 0 .. Scope_Stack
.Last
loop
3298 S
:= Scope_Stack
.Table
(J
).Entity
;
3300 if S
= Scope
(Ent
) then
3301 Error_Attr
("Caller must appear in matching accept or body", N
);
3307 Set_Etype
(N
, RTE
(RO_AT_Task_Id
));
3314 when Attribute_Ceiling
=>
3315 Check_Floating_Point_Type_1
;
3316 Set_Etype
(N
, P_Base_Type
);
3317 Resolve
(E1
, P_Base_Type
);
3323 when Attribute_Class
=>
3324 Check_Restriction
(No_Dispatch
, N
);
3328 -- Applying Class to untagged incomplete type is obsolescent in Ada
3329 -- 2005. Note that we can't test Is_Tagged_Type here on P_Type, since
3330 -- this flag gets set by Find_Type in this situation.
3332 if Restriction_Check_Required
(No_Obsolescent_Features
)
3333 and then Ada_Version
>= Ada_2005
3334 and then Ekind
(P_Type
) = E_Incomplete_Type
3337 DN
: constant Node_Id
:= Declaration_Node
(P_Type
);
3339 if Nkind
(DN
) = N_Incomplete_Type_Declaration
3340 and then not Tagged_Present
(DN
)
3342 Check_Restriction
(No_Obsolescent_Features
, P
);
3351 when Attribute_Code_Address
=>
3354 if Nkind
(P
) = N_Attribute_Reference
3355 and then Nam_In
(Attribute_Name
(P
), Name_Elab_Body
, Name_Elab_Spec
)
3359 elsif not Is_Entity_Name
(P
)
3360 or else (Ekind
(Entity
(P
)) /= E_Function
3362 Ekind
(Entity
(P
)) /= E_Procedure
)
3364 Error_Attr
("invalid prefix for % attribute", P
);
3365 Set_Address_Taken
(Entity
(P
));
3367 -- Issue an error if the prefix denotes an eliminated subprogram
3370 Check_For_Eliminated_Subprogram
(P
, Entity
(P
));
3373 Set_Etype
(N
, RTE
(RE_Address
));
3375 ----------------------
3376 -- Compiler_Version --
3377 ----------------------
3379 when Attribute_Compiler_Version
=>
3381 Check_Standard_Prefix
;
3382 Rewrite
(N
, Make_String_Literal
(Loc
, "GNAT " & Gnat_Version_String
));
3383 Analyze_And_Resolve
(N
, Standard_String
);
3384 Set_Is_Static_Expression
(N
, True);
3386 --------------------
3387 -- Component_Size --
3388 --------------------
3390 when Attribute_Component_Size
=>
3392 Set_Etype
(N
, Universal_Integer
);
3394 -- Note: unlike other array attributes, unconstrained arrays are OK
3396 if Is_Array_Type
(P_Type
) and then not Is_Constrained
(P_Type
) then
3406 when Attribute_Compose
=>
3407 Check_Floating_Point_Type_2
;
3408 Set_Etype
(N
, P_Base_Type
);
3409 Resolve
(E1
, P_Base_Type
);
3410 Resolve
(E2
, Any_Integer
);
3416 when Attribute_Constrained
=>
3418 Set_Etype
(N
, Standard_Boolean
);
3420 -- Case from RM J.4(2) of constrained applied to private type
3422 if Is_Entity_Name
(P
) and then Is_Type
(Entity
(P
)) then
3423 Check_Restriction
(No_Obsolescent_Features
, P
);
3425 if Warn_On_Obsolescent_Feature
then
3427 ("constrained for private type is an obsolescent feature "
3428 & "(RM J.4)?j?", N
);
3431 -- If we are within an instance, the attribute must be legal
3432 -- because it was valid in the generic unit. Ditto if this is
3433 -- an inlining of a function declared in an instance.
3435 if In_Instance
or else In_Inlined_Body
then
3438 -- For sure OK if we have a real private type itself, but must
3439 -- be completed, cannot apply Constrained to incomplete type.
3441 elsif Is_Private_Type
(Entity
(P
)) then
3443 -- Note: this is one of the Annex J features that does not
3444 -- generate a warning from -gnatwj, since in fact it seems
3445 -- very useful, and is used in the GNAT runtime.
3447 Check_Not_Incomplete_Type
;
3451 -- Normal (non-obsolescent case) of application to object of
3452 -- a discriminated type.
3455 Check_Object_Reference
(P
);
3457 -- If N does not come from source, then we allow the
3458 -- the attribute prefix to be of a private type whose
3459 -- full type has discriminants. This occurs in cases
3460 -- involving expanded calls to stream attributes.
3462 if not Comes_From_Source
(N
) then
3463 P_Type
:= Underlying_Type
(P_Type
);
3466 -- Must have discriminants or be an access type designating a type
3467 -- with discriminants. If it is a class-wide type it has unknown
3470 if Has_Discriminants
(P_Type
)
3471 or else Has_Unknown_Discriminants
(P_Type
)
3473 (Is_Access_Type
(P_Type
)
3474 and then Has_Discriminants
(Designated_Type
(P_Type
)))
3478 -- The rule given in 3.7.2 is part of static semantics, but the
3479 -- intent is clearly that it be treated as a legality rule, and
3480 -- rechecked in the visible part of an instance. Nevertheless
3481 -- the intent also seems to be it should legally apply to the
3482 -- actual of a formal with unknown discriminants, regardless of
3483 -- whether the actual has discriminants, in which case the value
3484 -- of the attribute is determined using the J.4 rules. This choice
3485 -- seems the most useful, and is compatible with existing tests.
3487 elsif In_Instance
then
3490 -- Also allow an object of a generic type if extensions allowed
3491 -- and allow this for any type at all. (this may be obsolete ???)
3493 elsif (Is_Generic_Type
(P_Type
)
3494 or else Is_Generic_Actual_Type
(P_Type
))
3495 and then Extensions_Allowed
3501 -- Fall through if bad prefix
3504 ("prefix of % attribute must be object of discriminated type");
3510 when Attribute_Copy_Sign
=>
3511 Check_Floating_Point_Type_2
;
3512 Set_Etype
(N
, P_Base_Type
);
3513 Resolve
(E1
, P_Base_Type
);
3514 Resolve
(E2
, P_Base_Type
);
3520 when Attribute_Count
=> Count
: declare
3528 if Nkind_In
(P
, N_Identifier
, N_Expanded_Name
) then
3531 if Ekind
(Ent
) /= E_Entry
then
3532 Error_Attr
("invalid entry name", N
);
3535 elsif Nkind
(P
) = N_Indexed_Component
then
3536 if not Is_Entity_Name
(Prefix
(P
))
3537 or else No
(Entity
(Prefix
(P
)))
3538 or else Ekind
(Entity
(Prefix
(P
))) /= E_Entry_Family
3540 if Nkind
(Prefix
(P
)) = N_Selected_Component
3541 and then Present
(Entity
(Selector_Name
(Prefix
(P
))))
3542 and then Ekind
(Entity
(Selector_Name
(Prefix
(P
)))) =
3546 ("attribute % must apply to entry of current task", P
);
3549 Error_Attr
("invalid entry family name", P
);
3554 Ent
:= Entity
(Prefix
(P
));
3557 elsif Nkind
(P
) = N_Selected_Component
3558 and then Present
(Entity
(Selector_Name
(P
)))
3559 and then Ekind
(Entity
(Selector_Name
(P
))) = E_Entry
3562 ("attribute % must apply to entry of current task", P
);
3565 Error_Attr
("invalid entry name", N
);
3569 for J
in reverse 0 .. Scope_Stack
.Last
loop
3570 S
:= Scope_Stack
.Table
(J
).Entity
;
3572 if S
= Scope
(Ent
) then
3573 if Nkind
(P
) = N_Expanded_Name
then
3574 Tsk
:= Entity
(Prefix
(P
));
3576 -- The prefix denotes either the task type, or else a
3577 -- single task whose task type is being analyzed.
3579 if (Is_Type
(Tsk
) and then Tsk
= S
)
3580 or else (not Is_Type
(Tsk
)
3581 and then Etype
(Tsk
) = S
3582 and then not (Comes_From_Source
(S
)))
3587 ("Attribute % must apply to entry of current task", N
);
3593 elsif Ekind
(Scope
(Ent
)) in Task_Kind
3594 and then not Ekind_In
(S
, E_Block
,
3599 Error_Attr
("Attribute % cannot appear in inner unit", N
);
3601 elsif Ekind
(Scope
(Ent
)) = E_Protected_Type
3602 and then not Has_Completion
(Scope
(Ent
))
3604 Error_Attr
("attribute % can only be used inside body", N
);
3608 if Is_Overloaded
(P
) then
3610 Index
: Interp_Index
;
3614 Get_First_Interp
(P
, Index
, It
);
3615 while Present
(It
.Nam
) loop
3616 if It
.Nam
= Ent
then
3619 -- Ada 2005 (AI-345): Do not consider primitive entry
3620 -- wrappers generated for task or protected types.
3622 elsif Ada_Version
>= Ada_2005
3623 and then not Comes_From_Source
(It
.Nam
)
3628 Error_Attr
("ambiguous entry name", N
);
3631 Get_Next_Interp
(Index
, It
);
3636 Set_Etype
(N
, Universal_Integer
);
3639 -----------------------
3640 -- Default_Bit_Order --
3641 -----------------------
3643 when Attribute_Default_Bit_Order
=> Default_Bit_Order
: declare
3644 Target_Default_Bit_Order
: System
.Bit_Order
;
3647 Check_Standard_Prefix
;
3649 if Bytes_Big_Endian
then
3650 Target_Default_Bit_Order
:= System
.High_Order_First
;
3652 Target_Default_Bit_Order
:= System
.Low_Order_First
;
3656 Make_Integer_Literal
(Loc
,
3657 UI_From_Int
(System
.Bit_Order
'Pos (Target_Default_Bit_Order
))));
3659 Set_Etype
(N
, Universal_Integer
);
3660 Set_Is_Static_Expression
(N
);
3661 end Default_Bit_Order
;
3663 ----------------------------------
3664 -- Default_Scalar_Storage_Order --
3665 ----------------------------------
3667 when Attribute_Default_Scalar_Storage_Order
=> Default_SSO
: declare
3668 RE_Default_SSO
: RE_Id
;
3671 Check_Standard_Prefix
;
3673 case Opt
.Default_SSO
is
3675 if Bytes_Big_Endian
then
3676 RE_Default_SSO
:= RE_High_Order_First
;
3678 RE_Default_SSO
:= RE_Low_Order_First
;
3682 RE_Default_SSO
:= RE_High_Order_First
;
3685 RE_Default_SSO
:= RE_Low_Order_First
;
3688 raise Program_Error
;
3691 Rewrite
(N
, New_Occurrence_Of
(RTE
(RE_Default_SSO
), Loc
));
3698 when Attribute_Definite
=>
3699 Legal_Formal_Attribute
;
3705 when Attribute_Delta
=>
3706 Check_Fixed_Point_Type_0
;
3707 Set_Etype
(N
, Universal_Real
);
3713 when Attribute_Denorm
=>
3714 Check_Floating_Point_Type_0
;
3715 Set_Etype
(N
, Standard_Boolean
);
3721 when Attribute_Deref
=>
3724 Resolve
(E1
, RTE
(RE_Address
));
3725 Set_Etype
(N
, P_Type
);
3727 ---------------------
3728 -- Descriptor_Size --
3729 ---------------------
3731 when Attribute_Descriptor_Size
=>
3734 if not Is_Entity_Name
(P
) or else not Is_Type
(Entity
(P
)) then
3735 Error_Attr_P
("prefix of attribute % must denote a type");
3738 Set_Etype
(N
, Universal_Integer
);
3744 when Attribute_Digits
=>
3748 if not Is_Floating_Point_Type
(P_Type
)
3749 and then not Is_Decimal_Fixed_Point_Type
(P_Type
)
3752 ("prefix of % attribute must be float or decimal type");
3755 Set_Etype
(N
, Universal_Integer
);
3761 -- Also handles processing for Elab_Spec and Elab_Subp_Body
3763 when Attribute_Elab_Body
3764 | Attribute_Elab_Spec
3765 | Attribute_Elab_Subp_Body
3768 Check_Unit_Name
(P
);
3769 Set_Etype
(N
, Standard_Void_Type
);
3771 -- We have to manually call the expander in this case to get
3772 -- the necessary expansion (normally attributes that return
3773 -- entities are not expanded).
3781 -- Shares processing with Elab_Body
3787 when Attribute_Elaborated
=>
3789 Check_Unit_Name
(P
);
3790 Set_Etype
(N
, Standard_Boolean
);
3796 when Attribute_Emax
=>
3797 Check_Floating_Point_Type_0
;
3798 Set_Etype
(N
, Universal_Integer
);
3804 when Attribute_Enabled
=>
3805 Check_Either_E0_Or_E1
;
3807 if Present
(E1
) then
3808 if not Is_Entity_Name
(E1
) or else No
(Entity
(E1
)) then
3809 Error_Msg_N
("entity name expected for Enabled attribute", E1
);
3814 if Nkind
(P
) /= N_Identifier
then
3815 Error_Msg_N
("identifier expected (check name)", P
);
3816 elsif Get_Check_Id
(Chars
(P
)) = No_Check_Id
then
3817 Error_Msg_N
("& is not a recognized check name", P
);
3820 Set_Etype
(N
, Standard_Boolean
);
3826 when Attribute_Enum_Rep
=>
3828 -- T'Enum_Rep (X) case
3830 if Present
(E1
) then
3832 Check_Discrete_Type
;
3833 Resolve
(E1
, P_Base_Type
);
3835 -- X'Enum_Rep case. X must be an object or enumeration literal, and
3836 -- it must be of a discrete type.
3839 ((Is_Object_Reference
(P
)
3842 and then Ekind
(Entity
(P
)) = E_Enumeration_Literal
))
3843 and then Is_Discrete_Type
(Etype
(P
)))
3845 Error_Attr_P
("prefix of % attribute must be discrete object");
3848 Set_Etype
(N
, Universal_Integer
);
3854 when Attribute_Enum_Val
=>
3858 if not Is_Enumeration_Type
(P_Type
) then
3859 Error_Attr_P
("prefix of % attribute must be enumeration type");
3862 -- If the enumeration type has a standard representation, the effect
3863 -- is the same as 'Val, so rewrite the attribute as a 'Val.
3865 if not Has_Non_Standard_Rep
(P_Base_Type
) then
3867 Make_Attribute_Reference
(Loc
,
3868 Prefix
=> Relocate_Node
(Prefix
(N
)),
3869 Attribute_Name
=> Name_Val
,
3870 Expressions
=> New_List
(Relocate_Node
(E1
))));
3871 Analyze_And_Resolve
(N
, P_Base_Type
);
3873 -- Non-standard representation case (enumeration with holes)
3877 Resolve
(E1
, Any_Integer
);
3878 Set_Etype
(N
, P_Base_Type
);
3885 when Attribute_Epsilon
=>
3886 Check_Floating_Point_Type_0
;
3887 Set_Etype
(N
, Universal_Real
);
3893 when Attribute_Exponent
=>
3894 Check_Floating_Point_Type_1
;
3895 Set_Etype
(N
, Universal_Integer
);
3896 Resolve
(E1
, P_Base_Type
);
3902 when Attribute_External_Tag
=>
3906 Set_Etype
(N
, Standard_String
);
3908 if not Is_Tagged_Type
(P_Type
) then
3909 Error_Attr_P
("prefix of % attribute must be tagged");
3916 when Attribute_Fast_Math
=>
3917 Check_Standard_Prefix
;
3918 Rewrite
(N
, New_Occurrence_Of
(Boolean_Literals
(Fast_Math
), Loc
));
3920 -----------------------
3921 -- Finalization_Size --
3922 -----------------------
3924 when Attribute_Finalization_Size
=>
3927 -- The prefix denotes an object
3929 if Is_Object_Reference
(P
) then
3930 Check_Object_Reference
(P
);
3932 -- The prefix denotes a type
3934 elsif Is_Entity_Name
(P
) and then Is_Type
(Entity
(P
)) then
3936 Check_Not_Incomplete_Type
;
3938 -- Attribute 'Finalization_Size is not defined for class-wide
3939 -- types because it is not possible to know statically whether
3940 -- a definite type will have controlled components or not.
3942 if Is_Class_Wide_Type
(Etype
(P
)) then
3944 ("prefix of % attribute cannot denote a class-wide type");
3947 -- The prefix denotes an illegal construct
3951 ("prefix of % attribute must be a definite type or an object");
3954 Set_Etype
(N
, Universal_Integer
);
3960 when Attribute_First
=>
3961 Check_Array_Or_Scalar_Type
;
3962 Bad_Attribute_For_Predicate
;
3968 when Attribute_First_Bit
=>
3970 Set_Etype
(N
, Universal_Integer
);
3976 when Attribute_First_Valid
=>
3977 Check_First_Last_Valid
;
3978 Set_Etype
(N
, P_Type
);
3984 when Attribute_Fixed_Value
=>
3986 Check_Fixed_Point_Type
;
3987 Resolve
(E1
, Any_Integer
);
3988 Set_Etype
(N
, P_Base_Type
);
3994 when Attribute_Floor
=>
3995 Check_Floating_Point_Type_1
;
3996 Set_Etype
(N
, P_Base_Type
);
3997 Resolve
(E1
, P_Base_Type
);
4003 when Attribute_Fore
=>
4004 Check_Fixed_Point_Type_0
;
4005 Set_Etype
(N
, Universal_Integer
);
4011 when Attribute_Fraction
=>
4012 Check_Floating_Point_Type_1
;
4013 Set_Etype
(N
, P_Base_Type
);
4014 Resolve
(E1
, P_Base_Type
);
4020 when Attribute_From_Any
=>
4022 Check_PolyORB_Attribute
;
4023 Set_Etype
(N
, P_Base_Type
);
4025 -----------------------
4026 -- Has_Access_Values --
4027 -----------------------
4029 when Attribute_Has_Access_Values
=>
4032 Set_Etype
(N
, Standard_Boolean
);
4034 ----------------------
4035 -- Has_Same_Storage --
4036 ----------------------
4038 when Attribute_Has_Same_Storage
=>
4041 -- The arguments must be objects of any type
4043 Analyze_And_Resolve
(P
);
4044 Analyze_And_Resolve
(E1
);
4045 Check_Object_Reference
(P
);
4046 Check_Object_Reference
(E1
);
4047 Set_Etype
(N
, Standard_Boolean
);
4049 -----------------------
4050 -- Has_Tagged_Values --
4051 -----------------------
4053 when Attribute_Has_Tagged_Values
=>
4056 Set_Etype
(N
, Standard_Boolean
);
4058 -----------------------
4059 -- Has_Discriminants --
4060 -----------------------
4062 when Attribute_Has_Discriminants
=>
4063 Legal_Formal_Attribute
;
4069 when Attribute_Identity
=>
4073 if Etype
(P
) = Standard_Exception_Type
then
4074 Set_Etype
(N
, RTE
(RE_Exception_Id
));
4076 -- Ada 2005 (AI-345): Attribute 'Identity may be applied to task
4077 -- interface class-wide types.
4079 elsif Is_Task_Type
(Etype
(P
))
4080 or else (Is_Access_Type
(Etype
(P
))
4081 and then Is_Task_Type
(Designated_Type
(Etype
(P
))))
4082 or else (Ada_Version
>= Ada_2005
4083 and then Ekind
(Etype
(P
)) = E_Class_Wide_Type
4084 and then Is_Interface
(Etype
(P
))
4085 and then Is_Task_Interface
(Etype
(P
)))
4088 Set_Etype
(N
, RTE
(RO_AT_Task_Id
));
4091 if Ada_Version
>= Ada_2005
then
4093 ("prefix of % attribute must be an exception, a task or a "
4094 & "task interface class-wide object");
4097 ("prefix of % attribute must be a task or an exception");
4105 when Attribute_Image
=>
4106 if Is_Real_Type
(P_Type
) then
4107 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
4108 Error_Msg_Name_1
:= Aname
;
4110 ("(Ada 83) % attribute not allowed for real types", N
);
4114 Analyze_Image_Attribute
(Standard_String
);
4120 when Attribute_Img
=>
4121 Analyze_Image_Attribute
(Standard_String
);
4127 when Attribute_Input
=>
4129 Check_Stream_Attribute
(TSS_Stream_Input
);
4130 Set_Etype
(N
, P_Base_Type
);
4136 when Attribute_Integer_Value
=>
4139 Resolve
(E1
, Any_Fixed
);
4141 -- Signal an error if argument type is not a specific fixed-point
4142 -- subtype. An error has been signalled already if the argument
4143 -- was not of a fixed-point type.
4145 if Etype
(E1
) = Any_Fixed
and then not Error_Posted
(E1
) then
4146 Error_Attr
("argument of % must be of a fixed-point type", E1
);
4149 Set_Etype
(N
, P_Base_Type
);
4155 when Attribute_Invalid_Value
=>
4158 Set_Etype
(N
, P_Base_Type
);
4159 Invalid_Value_Used
:= True;
4165 when Attribute_Large
=>
4168 Set_Etype
(N
, Universal_Real
);
4174 when Attribute_Last
=>
4175 Check_Array_Or_Scalar_Type
;
4176 Bad_Attribute_For_Predicate
;
4182 when Attribute_Last_Bit
=>
4184 Set_Etype
(N
, Universal_Integer
);
4190 when Attribute_Last_Valid
=>
4191 Check_First_Last_Valid
;
4192 Set_Etype
(N
, P_Type
);
4198 when Attribute_Leading_Part
=>
4199 Check_Floating_Point_Type_2
;
4200 Set_Etype
(N
, P_Base_Type
);
4201 Resolve
(E1
, P_Base_Type
);
4202 Resolve
(E2
, Any_Integer
);
4208 when Attribute_Length
=>
4210 Set_Etype
(N
, Universal_Integer
);
4216 when Attribute_Library_Level
=>
4219 if not Is_Entity_Name
(P
) then
4220 Error_Attr_P
("prefix of % attribute must be an entity name");
4223 if not Inside_A_Generic
then
4224 Set_Boolean_Result
(N
,
4225 Is_Library_Level_Entity
(Entity
(P
)));
4228 Set_Etype
(N
, Standard_Boolean
);
4234 when Attribute_Lock_Free
=>
4236 Set_Etype
(N
, Standard_Boolean
);
4238 if not Is_Protected_Type
(P_Type
) then
4240 ("prefix of % attribute must be a protected object");
4247 when Attribute_Loop_Entry
=> Loop_Entry
: declare
4248 procedure Check_References_In_Prefix
(Loop_Id
: Entity_Id
);
4249 -- Inspect the prefix for any uses of entities declared within the
4250 -- related loop. Loop_Id denotes the loop identifier.
4252 --------------------------------
4253 -- Check_References_In_Prefix --
4254 --------------------------------
4256 procedure Check_References_In_Prefix
(Loop_Id
: Entity_Id
) is
4257 Loop_Decl
: constant Node_Id
:= Label_Construct
(Parent
(Loop_Id
));
4259 function Check_Reference
(Nod
: Node_Id
) return Traverse_Result
;
4260 -- Determine whether a reference mentions an entity declared
4261 -- within the related loop.
4263 function Declared_Within
(Nod
: Node_Id
) return Boolean;
4264 -- Determine whether Nod appears in the subtree of Loop_Decl
4266 ---------------------
4267 -- Check_Reference --
4268 ---------------------
4270 function Check_Reference
(Nod
: Node_Id
) return Traverse_Result
is
4272 if Nkind
(Nod
) = N_Identifier
4273 and then Present
(Entity
(Nod
))
4274 and then Declared_Within
(Declaration_Node
(Entity
(Nod
)))
4277 ("prefix of attribute % cannot reference local entities",
4283 end Check_Reference
;
4285 procedure Check_References
is new Traverse_Proc
(Check_Reference
);
4287 ---------------------
4288 -- Declared_Within --
4289 ---------------------
4291 function Declared_Within
(Nod
: Node_Id
) return Boolean is
4296 while Present
(Stmt
) loop
4297 if Stmt
= Loop_Decl
then
4300 -- Prevent the search from going too far
4302 elsif Is_Body_Or_Package_Declaration
(Stmt
) then
4306 Stmt
:= Parent
(Stmt
);
4310 end Declared_Within
;
4312 -- Start of processing for Check_Prefix_For_Local_References
4315 Check_References
(P
);
4316 end Check_References_In_Prefix
;
4320 Context
: constant Node_Id
:= Parent
(N
);
4322 Encl_Loop
: Node_Id
:= Empty
;
4323 Encl_Prag
: Node_Id
:= Empty
;
4324 Loop_Id
: Entity_Id
:= Empty
;
4328 -- Start of processing for Loop_Entry
4333 -- Set the type of the attribute now to ensure the successful
4334 -- continuation of analysis even if the attribute is misplaced.
4336 Set_Etype
(Attr
, P_Type
);
4338 -- Attribute 'Loop_Entry may appear in several flavors:
4340 -- * Prefix'Loop_Entry - in this form, the attribute applies to the
4341 -- nearest enclosing loop.
4343 -- * Prefix'Loop_Entry (Expr) - depending on what Expr denotes, the
4344 -- attribute may be related to a loop denoted by label Expr or
4345 -- the prefix may denote an array object and Expr may act as an
4346 -- indexed component.
4348 -- * Prefix'Loop_Entry (Expr1, ..., ExprN) - the attribute applies
4349 -- to the nearest enclosing loop, all expressions are part of
4350 -- an indexed component.
4352 -- * Prefix'Loop_Entry (Expr) (...) (...) - depending on what Expr
4353 -- denotes, the attribute may be related to a loop denoted by
4354 -- label Expr or the prefix may denote a multidimensional array
4355 -- array object and Expr along with the rest of the expressions
4356 -- may act as indexed components.
4358 -- Regardless of variations, the attribute reference does not have an
4359 -- expression list. Instead, all available expressions are stored as
4360 -- indexed components.
4362 -- When the attribute is part of an indexed component, find the first
4363 -- expression as it will determine the semantics of 'Loop_Entry.
4365 -- If the attribute is itself an index in an indexed component, i.e.
4366 -- a member of a list, the context itself is not relevant (the code
4367 -- below would lead to an infinite loop) and the attribute applies
4368 -- to the enclosing loop.
4370 if Nkind
(Context
) = N_Indexed_Component
4371 and then not Is_List_Member
(N
)
4373 E1
:= First
(Expressions
(Context
));
4376 -- The attribute reference appears in the following form:
4378 -- Prefix'Loop_Entry (Exp1, Expr2, ..., ExprN) [(...)]
4380 -- In this case, the loop name is omitted and no rewriting is
4383 if Present
(E2
) then
4386 -- The form of the attribute is:
4388 -- Prefix'Loop_Entry (Expr) [(...)]
4390 -- If Expr denotes a loop entry, the whole attribute and indexed
4391 -- component will have to be rewritten to reflect this relation.
4394 pragma Assert
(Present
(E1
));
4396 -- Do not expand the expression as it may have side effects.
4397 -- Simply preanalyze to determine whether it is a loop name or
4400 Preanalyze_And_Resolve
(E1
);
4402 if Is_Entity_Name
(E1
)
4403 and then Present
(Entity
(E1
))
4404 and then Ekind
(Entity
(E1
)) = E_Loop
4406 Loop_Id
:= Entity
(E1
);
4408 -- Transform the attribute and enclosing indexed component
4410 Set_Expressions
(N
, Expressions
(Context
));
4411 Rewrite
(Context
, N
);
4412 Set_Etype
(Context
, P_Type
);
4419 -- The prefix must denote an object
4421 if not Is_Object_Reference
(P
) then
4422 Error_Attr_P
("prefix of attribute % must denote an object");
4425 -- The prefix cannot be of a limited type because the expansion of
4426 -- Loop_Entry must create a constant initialized by the evaluated
4429 if Is_Limited_View
(Etype
(P
)) then
4430 Error_Attr_P
("prefix of attribute % cannot be limited");
4433 -- Climb the parent chain to verify the location of the attribute and
4434 -- find the enclosing loop.
4437 while Present
(Stmt
) loop
4439 -- Locate the corresponding enclosing pragma. Note that in the
4440 -- case of Assert[And_Cut] and Assume, we have already checked
4441 -- that the pragma appears in an appropriate loop location.
4443 if Nkind
(Original_Node
(Stmt
)) = N_Pragma
4444 and then Nam_In
(Pragma_Name_Unmapped
(Original_Node
(Stmt
)),
4445 Name_Loop_Invariant
,
4448 Name_Assert_And_Cut
,
4451 Encl_Prag
:= Original_Node
(Stmt
);
4453 -- Locate the enclosing loop (if any). Note that Ada 2012 array
4454 -- iteration may be expanded into several nested loops, we are
4455 -- interested in the outermost one which has the loop identifier,
4456 -- and comes from source.
4458 elsif Nkind
(Stmt
) = N_Loop_Statement
4459 and then Present
(Identifier
(Stmt
))
4460 and then Comes_From_Source
(Original_Node
(Stmt
))
4461 and then Nkind
(Original_Node
(Stmt
)) = N_Loop_Statement
4465 -- The original attribute reference may lack a loop name. Use
4466 -- the name of the enclosing loop because it is the related
4469 if No
(Loop_Id
) then
4470 Loop_Id
:= Entity
(Identifier
(Encl_Loop
));
4475 -- Prevent the search from going too far
4477 elsif Is_Body_Or_Package_Declaration
(Stmt
) then
4481 Stmt
:= Parent
(Stmt
);
4484 -- Loop_Entry must appear within a Loop_Assertion pragma (Assert,
4485 -- Assert_And_Cut, Assume count as loop assertion pragmas for this
4486 -- purpose if they appear in an appropriate location in a loop,
4487 -- which was already checked by the top level pragma circuit).
4489 -- Loop_Entry also denotes a value and as such can appear within an
4490 -- expression that is an argument for another loop aspect. In that
4491 -- case it will have been expanded into the corresponding assignment.
4494 and then Nkind
(Parent
(N
)) = N_Assignment_Statement
4495 and then not Comes_From_Source
(Parent
(N
))
4499 elsif No
(Encl_Prag
) then
4500 Error_Attr
("attribute% must appear within appropriate pragma", N
);
4503 -- A Loop_Entry that applies to a given loop statement must not
4504 -- appear within a body of accept statement, if this construct is
4505 -- itself enclosed by the given loop statement.
4507 for Index
in reverse 0 .. Scope_Stack
.Last
loop
4508 Scop
:= Scope_Stack
.Table
(Index
).Entity
;
4510 if Ekind
(Scop
) = E_Loop
and then Scop
= Loop_Id
then
4512 elsif Ekind_In
(Scop
, E_Block
, E_Loop
, E_Return_Statement
) then
4516 ("attribute % cannot appear in body or accept statement", N
);
4521 -- The prefix cannot mention entities declared within the related
4522 -- loop because they will not be visible once the prefix is moved
4523 -- outside the loop.
4525 Check_References_In_Prefix
(Loop_Id
);
4527 -- The prefix must denote a static entity if the pragma does not
4528 -- apply to the innermost enclosing loop statement, or if it appears
4529 -- within a potentially unevaluated epxression.
4531 if Is_Entity_Name
(P
)
4532 or else Nkind
(Parent
(P
)) = N_Object_Renaming_Declaration
4533 or else Statically_Denotes_Object
(P
)
4537 elsif Present
(Encl_Loop
)
4538 and then Entity
(Identifier
(Encl_Loop
)) /= Loop_Id
4541 ("prefix of attribute % that applies to outer loop must denote "
4544 elsif Is_Potentially_Unevaluated
(P
) then
4548 -- Replace the Loop_Entry attribute reference by its prefix if the
4549 -- related pragma is ignored. This transformation is OK with respect
4550 -- to typing because Loop_Entry's type is that of its prefix. This
4551 -- early transformation also avoids the generation of a useless loop
4554 if Present
(Encl_Prag
) and then Is_Ignored
(Encl_Prag
) then
4555 Rewrite
(N
, Relocate_Node
(P
));
4556 Preanalyze_And_Resolve
(N
);
4559 Preanalyze_And_Resolve
(P
);
4567 when Attribute_Machine
=>
4568 Check_Floating_Point_Type_1
;
4569 Set_Etype
(N
, P_Base_Type
);
4570 Resolve
(E1
, P_Base_Type
);
4576 when Attribute_Machine_Emax
=>
4577 Check_Floating_Point_Type_0
;
4578 Set_Etype
(N
, Universal_Integer
);
4584 when Attribute_Machine_Emin
=>
4585 Check_Floating_Point_Type_0
;
4586 Set_Etype
(N
, Universal_Integer
);
4588 ----------------------
4589 -- Machine_Mantissa --
4590 ----------------------
4592 when Attribute_Machine_Mantissa
=>
4593 Check_Floating_Point_Type_0
;
4594 Set_Etype
(N
, Universal_Integer
);
4596 -----------------------
4597 -- Machine_Overflows --
4598 -----------------------
4600 when Attribute_Machine_Overflows
=>
4603 Set_Etype
(N
, Standard_Boolean
);
4609 when Attribute_Machine_Radix
=>
4612 Set_Etype
(N
, Universal_Integer
);
4614 ----------------------
4615 -- Machine_Rounding --
4616 ----------------------
4618 when Attribute_Machine_Rounding
=>
4619 Check_Floating_Point_Type_1
;
4620 Set_Etype
(N
, P_Base_Type
);
4621 Resolve
(E1
, P_Base_Type
);
4623 --------------------
4624 -- Machine_Rounds --
4625 --------------------
4627 when Attribute_Machine_Rounds
=>
4630 Set_Etype
(N
, Standard_Boolean
);
4636 when Attribute_Machine_Size
=>
4639 Check_Not_Incomplete_Type
;
4640 Set_Etype
(N
, Universal_Integer
);
4646 when Attribute_Mantissa
=>
4649 Set_Etype
(N
, Universal_Integer
);
4655 when Attribute_Max
=>
4658 ----------------------------------
4659 -- Max_Alignment_For_Allocation --
4660 ----------------------------------
4662 when Attribute_Max_Size_In_Storage_Elements
=>
4663 Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
;
4665 ----------------------------------
4666 -- Max_Size_In_Storage_Elements --
4667 ----------------------------------
4669 when Attribute_Max_Alignment_For_Allocation
=>
4670 Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
;
4672 -----------------------
4673 -- Maximum_Alignment --
4674 -----------------------
4676 when Attribute_Maximum_Alignment
=>
4677 Standard_Attribute
(Ttypes
.Maximum_Alignment
);
4679 --------------------
4680 -- Mechanism_Code --
4681 --------------------
4683 when Attribute_Mechanism_Code
=>
4684 if not Is_Entity_Name
(P
)
4685 or else not Is_Subprogram
(Entity
(P
))
4687 Error_Attr_P
("prefix of % attribute must be subprogram");
4690 Check_Either_E0_Or_E1
;
4692 if Present
(E1
) then
4693 Resolve
(E1
, Any_Integer
);
4694 Set_Etype
(E1
, Standard_Integer
);
4696 if not Is_OK_Static_Expression
(E1
) then
4697 Flag_Non_Static_Expr
4698 ("expression for parameter number must be static!", E1
);
4701 elsif UI_To_Int
(Intval
(E1
)) > Number_Formals
(Entity
(P
))
4702 or else UI_To_Int
(Intval
(E1
)) < 0
4704 Error_Attr
("invalid parameter number for % attribute", E1
);
4708 Set_Etype
(N
, Universal_Integer
);
4714 when Attribute_Min
=>
4721 when Attribute_Mod
=>
4723 -- Note: this attribute is only allowed in Ada 2005 mode, but
4724 -- we do not need to test that here, since Mod is only recognized
4725 -- as an attribute name in Ada 2005 mode during the parse.
4728 Check_Modular_Integer_Type
;
4729 Resolve
(E1
, Any_Integer
);
4730 Set_Etype
(N
, P_Base_Type
);
4736 when Attribute_Model
=>
4737 Check_Floating_Point_Type_1
;
4738 Set_Etype
(N
, P_Base_Type
);
4739 Resolve
(E1
, P_Base_Type
);
4745 when Attribute_Model_Emin
=>
4746 Check_Floating_Point_Type_0
;
4747 Set_Etype
(N
, Universal_Integer
);
4753 when Attribute_Model_Epsilon
=>
4754 Check_Floating_Point_Type_0
;
4755 Set_Etype
(N
, Universal_Real
);
4757 --------------------
4758 -- Model_Mantissa --
4759 --------------------
4761 when Attribute_Model_Mantissa
=>
4762 Check_Floating_Point_Type_0
;
4763 Set_Etype
(N
, Universal_Integer
);
4769 when Attribute_Model_Small
=>
4770 Check_Floating_Point_Type_0
;
4771 Set_Etype
(N
, Universal_Real
);
4777 when Attribute_Modulus
=>
4779 Check_Modular_Integer_Type
;
4780 Set_Etype
(N
, Universal_Integer
);
4782 --------------------
4783 -- Null_Parameter --
4784 --------------------
4786 when Attribute_Null_Parameter
=> Null_Parameter
: declare
4787 Parnt
: constant Node_Id
:= Parent
(N
);
4788 GParnt
: constant Node_Id
:= Parent
(Parnt
);
4790 procedure Bad_Null_Parameter
(Msg
: String);
4791 -- Used if bad Null parameter attribute node is found. Issues
4792 -- given error message, and also sets the type to Any_Type to
4793 -- avoid blowups later on from dealing with a junk node.
4795 procedure Must_Be_Imported
(Proc_Ent
: Entity_Id
);
4796 -- Called to check that Proc_Ent is imported subprogram
4798 ------------------------
4799 -- Bad_Null_Parameter --
4800 ------------------------
4802 procedure Bad_Null_Parameter
(Msg
: String) is
4804 Error_Msg_N
(Msg
, N
);
4805 Set_Etype
(N
, Any_Type
);
4806 end Bad_Null_Parameter
;
4808 ----------------------
4809 -- Must_Be_Imported --
4810 ----------------------
4812 procedure Must_Be_Imported
(Proc_Ent
: Entity_Id
) is
4813 Pent
: constant Entity_Id
:= Ultimate_Alias
(Proc_Ent
);
4816 -- Ignore check if procedure not frozen yet (we will get
4817 -- another chance when the default parameter is reanalyzed)
4819 if not Is_Frozen
(Pent
) then
4822 elsif not Is_Imported
(Pent
) then
4824 ("Null_Parameter can only be used with imported subprogram");
4829 end Must_Be_Imported
;
4831 -- Start of processing for Null_Parameter
4836 Set_Etype
(N
, P_Type
);
4838 -- Case of attribute used as default expression
4840 if Nkind
(Parnt
) = N_Parameter_Specification
then
4841 Must_Be_Imported
(Defining_Entity
(GParnt
));
4843 -- Case of attribute used as actual for subprogram (positional)
4845 elsif Nkind
(Parnt
) in N_Subprogram_Call
4846 and then Is_Entity_Name
(Name
(Parnt
))
4848 Must_Be_Imported
(Entity
(Name
(Parnt
)));
4850 -- Case of attribute used as actual for subprogram (named)
4852 elsif Nkind
(Parnt
) = N_Parameter_Association
4853 and then Nkind
(GParnt
) in N_Subprogram_Call
4854 and then Is_Entity_Name
(Name
(GParnt
))
4856 Must_Be_Imported
(Entity
(Name
(GParnt
)));
4858 -- Not an allowed case
4862 ("Null_Parameter must be actual or default parameter");
4870 when Attribute_Object_Size
=>
4873 Check_Not_Incomplete_Type
;
4874 Set_Etype
(N
, Universal_Integer
);
4880 when Attribute_Old
=> Old
: declare
4881 procedure Check_References_In_Prefix
(Subp_Id
: Entity_Id
);
4882 -- Inspect the contents of the prefix and detect illegal uses of a
4883 -- nested 'Old, attribute 'Result or a use of an entity declared in
4884 -- the related postcondition expression. Subp_Id is the subprogram to
4885 -- which the related postcondition applies.
4887 --------------------------------
4888 -- Check_References_In_Prefix --
4889 --------------------------------
4891 procedure Check_References_In_Prefix
(Subp_Id
: Entity_Id
) is
4892 function Check_Reference
(Nod
: Node_Id
) return Traverse_Result
;
4893 -- Detect attribute 'Old, attribute 'Result of a use of an entity
4894 -- and perform the appropriate semantic check.
4896 ---------------------
4897 -- Check_Reference --
4898 ---------------------
4900 function Check_Reference
(Nod
: Node_Id
) return Traverse_Result
is
4902 -- Attributes 'Old and 'Result cannot appear in the prefix of
4903 -- another attribute 'Old.
4905 if Nkind
(Nod
) = N_Attribute_Reference
4906 and then Nam_In
(Attribute_Name
(Nod
), Name_Old
,
4909 Error_Msg_Name_1
:= Attribute_Name
(Nod
);
4910 Error_Msg_Name_2
:= Name_Old
;
4912 ("attribute % cannot appear in the prefix of attribute %",
4916 -- Entities mentioned within the prefix of attribute 'Old must
4917 -- be global to the related postcondition. If this is not the
4918 -- case, then the scope of the local entity is nested within
4919 -- that of the subprogram.
4921 elsif Is_Entity_Name
(Nod
)
4922 and then Present
(Entity
(Nod
))
4923 and then Scope_Within
(Scope
(Entity
(Nod
)), Subp_Id
)
4926 ("prefix of attribute % cannot reference local entities",
4930 -- Otherwise keep inspecting the prefix
4935 end Check_Reference
;
4937 procedure Check_References
is new Traverse_Proc
(Check_Reference
);
4939 -- Start of processing for Check_References_In_Prefix
4942 Check_References
(P
);
4943 end Check_References_In_Prefix
;
4948 Pref_Id
: Entity_Id
;
4949 Pref_Typ
: Entity_Id
;
4950 Spec_Id
: Entity_Id
;
4952 -- Start of processing for Old
4955 -- The attribute reference is a primary. If any expressions follow,
4956 -- then the attribute reference is an indexable object. Transform the
4957 -- attribute into an indexed component and analyze it.
4959 if Present
(E1
) then
4961 Make_Indexed_Component
(Loc
,
4963 Make_Attribute_Reference
(Loc
,
4964 Prefix
=> Relocate_Node
(P
),
4965 Attribute_Name
=> Name_Old
),
4966 Expressions
=> Expressions
(N
)));
4971 Analyze_Attribute_Old_Result
(Legal
, Spec_Id
);
4973 -- The aspect or pragma where attribute 'Old resides should be
4974 -- associated with a subprogram declaration or a body. If this is not
4975 -- the case, then the aspect or pragma is illegal. Return as analysis
4976 -- cannot be carried out.
4978 -- The exception to this rule is when generating C since in this case
4979 -- postconditions are inlined.
4982 and then Modify_Tree_For_C
4983 and then In_Inlined_Body
4985 Spec_Id
:= Entity
(P
);
4987 elsif not Legal
then
4991 -- The prefix must be preanalyzed as the full analysis will take
4992 -- place during expansion.
4994 Preanalyze_And_Resolve
(P
);
4996 -- Ensure that the prefix does not contain attributes 'Old or 'Result
4998 Check_References_In_Prefix
(Spec_Id
);
5000 -- Set the type of the attribute now to prevent cascaded errors
5002 Pref_Typ
:= Etype
(P
);
5003 Set_Etype
(N
, Pref_Typ
);
5007 if Is_Limited_Type
(Pref_Typ
) then
5008 Error_Attr
("attribute % cannot apply to limited objects", P
);
5011 -- The prefix is a simple name
5013 if Is_Entity_Name
(P
) and then Present
(Entity
(P
)) then
5014 Pref_Id
:= Entity
(P
);
5016 -- Emit a warning when the prefix is a constant. Note that the use
5017 -- of Error_Attr would reset the type of N to Any_Type even though
5018 -- this is a warning. Use Error_Msg_XXX instead.
5020 if Is_Constant_Object
(Pref_Id
) then
5021 Error_Msg_Name_1
:= Name_Old
;
5023 ("??attribute % applied to constant has no effect", P
);
5026 -- Otherwise the prefix is not a simple name
5029 -- Ensure that the prefix of attribute 'Old is an entity when it
5030 -- is potentially unevaluated (6.1.1 (27/3)).
5032 if Is_Potentially_Unevaluated
(N
)
5033 and then not Statically_Denotes_Object
(P
)
5037 -- Detect a possible infinite recursion when the prefix denotes
5038 -- the related function.
5040 -- function Func (...) return ...
5041 -- with Post => Func'Old ...;
5043 -- The function may be specified in qualified form X.Y where X is
5044 -- a protected object and Y is a protected function. In that case
5045 -- ensure that the qualified form has an entity.
5047 elsif Nkind
(P
) = N_Function_Call
5048 and then Nkind
(Name
(P
)) in N_Has_Entity
5050 Pref_Id
:= Entity
(Name
(P
));
5052 if Ekind_In
(Spec_Id
, E_Function
, E_Generic_Function
)
5053 and then Pref_Id
= Spec_Id
5055 Error_Msg_Warn
:= SPARK_Mode
/= On
;
5056 Error_Msg_N
("!possible infinite recursion<<", P
);
5057 Error_Msg_N
("\!??Storage_Error ]<<", P
);
5061 -- The prefix of attribute 'Old may refer to a component of a
5062 -- formal parameter. In this case its expansion may generate
5063 -- actual subtypes that are referenced in an inner context and
5064 -- that must be elaborated within the subprogram itself. If the
5065 -- prefix includes a function call, it may involve finalization
5066 -- actions that should be inserted when the attribute has been
5067 -- rewritten as a declaration. Create a declaration for the prefix
5068 -- and insert it at the start of the enclosing subprogram. This is
5069 -- an expansion activity that has to be performed now to prevent
5070 -- out-of-order issues.
5072 -- This expansion is both harmful and not needed in SPARK mode,
5073 -- since the formal verification back end relies on the types of
5074 -- nodes (hence is not robust w.r.t. a change to base type here),
5075 -- and does not suffer from the out-of-order issue described
5076 -- above. Thus, this expansion is skipped in SPARK mode.
5078 -- The expansion is not relevant for discrete types, which will
5079 -- not generate extra declarations, and where use of the base type
5080 -- may lead to spurious errors if context is a case.
5082 if not GNATprove_Mode
then
5083 if not Is_Discrete_Type
(Pref_Typ
) then
5084 Pref_Typ
:= Base_Type
(Pref_Typ
);
5087 Set_Etype
(N
, Pref_Typ
);
5088 Set_Etype
(P
, Pref_Typ
);
5090 Analyze_Dimension
(N
);
5096 ----------------------
5097 -- Overlaps_Storage --
5098 ----------------------
5100 when Attribute_Overlaps_Storage
=>
5103 -- Both arguments must be objects of any type
5105 Analyze_And_Resolve
(P
);
5106 Analyze_And_Resolve
(E1
);
5107 Check_Object_Reference
(P
);
5108 Check_Object_Reference
(E1
);
5109 Set_Etype
(N
, Standard_Boolean
);
5115 when Attribute_Output
=>
5117 Check_Stream_Attribute
(TSS_Stream_Output
);
5118 Set_Etype
(N
, Standard_Void_Type
);
5119 Resolve
(N
, Standard_Void_Type
);
5125 when Attribute_Partition_ID
=>
5128 if P_Type
/= Any_Type
then
5129 if not Is_Library_Level_Entity
(Entity
(P
)) then
5131 ("prefix of % attribute must be library-level entity");
5133 -- The defining entity of prefix should not be declared inside a
5134 -- Pure unit. RM E.1(8). Is_Pure was set during declaration.
5136 elsif Is_Entity_Name
(P
)
5137 and then Is_Pure
(Entity
(P
))
5139 Error_Attr_P
("prefix of% attribute must not be declared pure");
5143 Set_Etype
(N
, Universal_Integer
);
5145 -------------------------
5146 -- Passed_By_Reference --
5147 -------------------------
5149 when Attribute_Passed_By_Reference
=>
5152 Set_Etype
(N
, Standard_Boolean
);
5158 when Attribute_Pool_Address
=>
5160 Set_Etype
(N
, RTE
(RE_Address
));
5166 when Attribute_Pos
=>
5167 Check_Discrete_Type
;
5170 if Is_Boolean_Type
(P_Type
) then
5171 Error_Msg_Name_1
:= Aname
;
5172 Error_Msg_Name_2
:= Chars
(P_Type
);
5173 Check_SPARK_05_Restriction
5174 ("attribute% is not allowed for type%", P
);
5177 Resolve
(E1
, P_Base_Type
);
5178 Set_Etype
(N
, Universal_Integer
);
5184 when Attribute_Position
=>
5186 Set_Etype
(N
, Universal_Integer
);
5192 when Attribute_Pred
=>
5196 if Is_Real_Type
(P_Type
) or else Is_Boolean_Type
(P_Type
) then
5197 Error_Msg_Name_1
:= Aname
;
5198 Error_Msg_Name_2
:= Chars
(P_Type
);
5199 Check_SPARK_05_Restriction
5200 ("attribute% is not allowed for type%", P
);
5203 Resolve
(E1
, P_Base_Type
);
5204 Set_Etype
(N
, P_Base_Type
);
5206 -- Since Pred works on the base type, we normally do no check for the
5207 -- floating-point case, since the base type is unconstrained. But we
5208 -- make an exception in Check_Float_Overflow mode.
5210 if Is_Floating_Point_Type
(P_Type
) then
5211 if not Range_Checks_Suppressed
(P_Base_Type
) then
5212 Set_Do_Range_Check
(E1
);
5215 -- If not modular type, test for overflow check required
5218 if not Is_Modular_Integer_Type
(P_Type
)
5219 and then not Range_Checks_Suppressed
(P_Base_Type
)
5221 Enable_Range_Check
(E1
);
5229 -- Ada 2005 (AI-327): Dynamic ceiling priorities
5231 when Attribute_Priority
=>
5232 if Ada_Version
< Ada_2005
then
5233 Error_Attr
("% attribute is allowed only in Ada 2005 mode", P
);
5238 Check_Restriction
(No_Dynamic_Priorities
, N
);
5240 -- The prefix must be a protected object (AARM D.5.2 (2/2))
5244 if Is_Protected_Type
(Etype
(P
))
5245 or else (Is_Access_Type
(Etype
(P
))
5246 and then Is_Protected_Type
(Designated_Type
(Etype
(P
))))
5248 Resolve
(P
, Etype
(P
));
5250 Error_Attr_P
("prefix of % attribute must be a protected object");
5253 Set_Etype
(N
, Standard_Integer
);
5255 -- Must be called from within a protected procedure or entry of the
5256 -- protected object.
5263 while S
/= Etype
(P
)
5264 and then S
/= Standard_Standard
5269 if S
= Standard_Standard
then
5270 Error_Attr
("the attribute % is only allowed inside protected "
5275 Validate_Non_Static_Attribute_Function_Call
;
5281 when Attribute_Range
=>
5282 Check_Array_Or_Scalar_Type
;
5283 Bad_Attribute_For_Predicate
;
5285 if Ada_Version
= Ada_83
5286 and then Is_Scalar_Type
(P_Type
)
5287 and then Comes_From_Source
(N
)
5290 ("(Ada 83) % attribute not allowed for scalar type", P
);
5297 when Attribute_Result
=> Result
: declare
5298 function Denote_Same_Function
5299 (Pref_Id
: Entity_Id
;
5300 Spec_Id
: Entity_Id
) return Boolean;
5301 -- Determine whether the entity of the prefix Pref_Id denotes the
5302 -- same entity as that of the related subprogram Spec_Id.
5304 --------------------------
5305 -- Denote_Same_Function --
5306 --------------------------
5308 function Denote_Same_Function
5309 (Pref_Id
: Entity_Id
;
5310 Spec_Id
: Entity_Id
) return Boolean
5312 Over_Id
: constant Entity_Id
:= Overridden_Operation
(Spec_Id
);
5313 Subp_Spec
: constant Node_Id
:= Parent
(Spec_Id
);
5316 -- The prefix denotes the related subprogram
5318 if Pref_Id
= Spec_Id
then
5321 -- Account for a special case when attribute 'Result appears in
5322 -- the postcondition of a generic function.
5325 -- function Gen_Func return ...
5326 -- with Post => Gen_Func'Result ...;
5328 -- When the generic function is instantiated, the Chars field of
5329 -- the instantiated prefix still denotes the name of the generic
5330 -- function. Note that any preemptive transformation is impossible
5331 -- without a proper analysis. The structure of the wrapper package
5334 -- package Anon_Gen_Pack is
5335 -- <subtypes and renamings>
5336 -- function Subp_Decl return ...; -- (!)
5337 -- pragma Postcondition (Gen_Func'Result ...); -- (!)
5338 -- function Gen_Func ... renames Subp_Decl;
5339 -- end Anon_Gen_Pack;
5341 elsif Nkind
(Subp_Spec
) = N_Function_Specification
5342 and then Present
(Generic_Parent
(Subp_Spec
))
5343 and then Ekind_In
(Pref_Id
, E_Generic_Function
, E_Function
)
5345 if Generic_Parent
(Subp_Spec
) = Pref_Id
then
5348 elsif Present
(Alias
(Pref_Id
))
5349 and then Alias
(Pref_Id
) = Spec_Id
5354 -- Account for a special case where a primitive of a tagged type
5355 -- inherits a class-wide postcondition from a parent type. In this
5356 -- case the prefix of attribute 'Result denotes the overriding
5359 elsif Present
(Over_Id
) and then Pref_Id
= Over_Id
then
5363 -- Otherwise the prefix does not denote the related subprogram
5366 end Denote_Same_Function
;
5370 In_Inlined_C_Postcondition
: constant Boolean :=
5372 and then In_Inlined_Body
;
5375 Pref_Id
: Entity_Id
;
5376 Spec_Id
: Entity_Id
;
5378 -- Start of processing for Result
5381 -- The attribute reference is a primary. If any expressions follow,
5382 -- then the attribute reference is an indexable object. Transform the
5383 -- attribute into an indexed component and analyze it.
5385 if Present
(E1
) then
5387 Make_Indexed_Component
(Loc
,
5389 Make_Attribute_Reference
(Loc
,
5390 Prefix
=> Relocate_Node
(P
),
5391 Attribute_Name
=> Name_Result
),
5392 Expressions
=> Expressions
(N
)));
5397 Analyze_Attribute_Old_Result
(Legal
, Spec_Id
);
5399 -- The aspect or pragma where attribute 'Result resides should be
5400 -- associated with a subprogram declaration or a body. If this is not
5401 -- the case, then the aspect or pragma is illegal. Return as analysis
5402 -- cannot be carried out.
5404 -- The exception to this rule is when generating C since in this case
5405 -- postconditions are inlined.
5407 if No
(Spec_Id
) and then In_Inlined_C_Postcondition
then
5408 Spec_Id
:= Entity
(P
);
5410 elsif not Legal
then
5414 -- Attribute 'Result is part of a _Postconditions procedure. There is
5415 -- no need to perform the semantic checks below as they were already
5416 -- verified when the attribute was analyzed in its original context.
5417 -- Instead, rewrite the attribute as a reference to formal parameter
5418 -- _Result of the _Postconditions procedure.
5420 if Chars
(Spec_Id
) = Name_uPostconditions
5422 (In_Inlined_C_Postcondition
5423 and then Nkind
(Parent
(Spec_Id
)) = N_Block_Statement
)
5425 Rewrite
(N
, Make_Identifier
(Loc
, Name_uResult
));
5427 -- The type of formal parameter _Result is that of the function
5428 -- encapsulating the _Postconditions procedure. Resolution must
5429 -- be carried out against the function return type.
5431 Analyze_And_Resolve
(N
, Etype
(Scope
(Spec_Id
)));
5433 -- Otherwise attribute 'Result appears in its original context and
5434 -- all semantic checks should be carried out.
5437 -- Verify the legality of the prefix. It must denotes the entity
5438 -- of the related [generic] function.
5440 if Is_Entity_Name
(P
) then
5441 Pref_Id
:= Entity
(P
);
5443 if Ekind_In
(Pref_Id
, E_Function
, E_Generic_Function
)
5444 and then Ekind
(Spec_Id
) = Ekind
(Pref_Id
)
5446 if Denote_Same_Function
(Pref_Id
, Spec_Id
) then
5448 -- Correct the prefix of the attribute when the context
5449 -- is a generic function.
5451 if Pref_Id
/= Spec_Id
then
5452 Rewrite
(P
, New_Occurrence_Of
(Spec_Id
, Loc
));
5456 Set_Etype
(N
, Etype
(Spec_Id
));
5458 -- Otherwise the prefix denotes some unrelated function
5461 Error_Msg_Name_2
:= Chars
(Spec_Id
);
5463 ("incorrect prefix for attribute %, expected %", P
);
5466 -- Otherwise the prefix denotes some other form of subprogram
5471 ("attribute % can only appear in postcondition of "
5475 -- Otherwise the prefix is illegal
5478 Error_Msg_Name_2
:= Chars
(Spec_Id
);
5479 Error_Attr
("incorrect prefix for attribute %, expected %", P
);
5488 when Attribute_Range_Length
=>
5490 Check_Discrete_Type
;
5491 Set_Etype
(N
, Universal_Integer
);
5497 when Attribute_Read
=>
5499 Check_Stream_Attribute
(TSS_Stream_Read
);
5500 Set_Etype
(N
, Standard_Void_Type
);
5501 Resolve
(N
, Standard_Void_Type
);
5502 Note_Possible_Modification
(E2
, Sure
=> True);
5508 when Attribute_Ref
=>
5512 if Nkind
(P
) /= N_Expanded_Name
5513 or else not Is_RTE
(P_Type
, RE_Address
)
5515 Error_Attr_P
("prefix of % attribute must be System.Address");
5518 Analyze_And_Resolve
(E1
, Any_Integer
);
5519 Set_Etype
(N
, RTE
(RE_Address
));
5525 when Attribute_Remainder
=>
5526 Check_Floating_Point_Type_2
;
5527 Set_Etype
(N
, P_Base_Type
);
5528 Resolve
(E1
, P_Base_Type
);
5529 Resolve
(E2
, P_Base_Type
);
5531 ---------------------
5532 -- Restriction_Set --
5533 ---------------------
5535 when Attribute_Restriction_Set
=> Restriction_Set
: declare
5538 Unam
: Unit_Name_Type
;
5543 Check_System_Prefix
;
5545 -- No_Dependence case
5547 if Nkind
(E1
) = N_Parameter_Association
then
5548 pragma Assert
(Chars
(Selector_Name
(E1
)) = Name_No_Dependence
);
5549 U
:= Explicit_Actual_Parameter
(E1
);
5551 if not OK_No_Dependence_Unit_Name
(U
) then
5552 Set_Boolean_Result
(N
, False);
5556 -- See if there is an entry already in the table. That's the
5557 -- case in which we can return True.
5559 for J
in No_Dependences
.First
.. No_Dependences
.Last
loop
5560 if Designate_Same_Unit
(U
, No_Dependences
.Table
(J
).Unit
)
5561 and then No_Dependences
.Table
(J
).Warn
= False
5563 Set_Boolean_Result
(N
, True);
5568 -- If not in the No_Dependence table, result is False
5570 Set_Boolean_Result
(N
, False);
5572 -- In this case, we must ensure that the binder will reject any
5573 -- other unit in the partition that sets No_Dependence for this
5574 -- unit. We do that by making an entry in the special table kept
5575 -- for this purpose (if the entry is not there already).
5577 Unam
:= Get_Spec_Name
(Get_Unit_Name
(U
));
5579 for J
in Restriction_Set_Dependences
.First
..
5580 Restriction_Set_Dependences
.Last
5582 if Restriction_Set_Dependences
.Table
(J
) = Unam
then
5587 Restriction_Set_Dependences
.Append
(Unam
);
5589 -- Normal restriction case
5592 if Nkind
(E1
) /= N_Identifier
then
5593 Set_Boolean_Result
(N
, False);
5594 Error_Attr
("attribute % requires restriction identifier", E1
);
5597 R
:= Get_Restriction_Id
(Process_Restriction_Synonyms
(E1
));
5599 if R
= Not_A_Restriction_Id
then
5600 Set_Boolean_Result
(N
, False);
5601 Error_Msg_Node_1
:= E1
;
5602 Error_Attr
("invalid restriction identifier &", E1
);
5604 elsif R
not in Partition_Boolean_Restrictions
then
5605 Set_Boolean_Result
(N
, False);
5606 Error_Msg_Node_1
:= E1
;
5608 ("& is not a boolean partition-wide restriction", E1
);
5611 if Restriction_Active
(R
) then
5612 Set_Boolean_Result
(N
, True);
5614 Check_Restriction
(R
, N
);
5615 Set_Boolean_Result
(N
, False);
5619 end Restriction_Set
;
5625 when Attribute_Round
=>
5627 Check_Decimal_Fixed_Point_Type
;
5628 Set_Etype
(N
, P_Base_Type
);
5630 -- Because the context is universal_real (3.5.10(12)) it is a
5631 -- legal context for a universal fixed expression. This is the
5632 -- only attribute whose functional description involves U_R.
5634 if Etype
(E1
) = Universal_Fixed
then
5636 Conv
: constant Node_Id
:= Make_Type_Conversion
(Loc
,
5637 Subtype_Mark
=> New_Occurrence_Of
(Universal_Real
, Loc
),
5638 Expression
=> Relocate_Node
(E1
));
5646 Resolve
(E1
, Any_Real
);
5652 when Attribute_Rounding
=>
5653 Check_Floating_Point_Type_1
;
5654 Set_Etype
(N
, P_Base_Type
);
5655 Resolve
(E1
, P_Base_Type
);
5661 when Attribute_Safe_Emax
=>
5662 Check_Floating_Point_Type_0
;
5663 Set_Etype
(N
, Universal_Integer
);
5669 when Attribute_Safe_First
=>
5670 Check_Floating_Point_Type_0
;
5671 Set_Etype
(N
, Universal_Real
);
5677 when Attribute_Safe_Large
=>
5680 Set_Etype
(N
, Universal_Real
);
5686 when Attribute_Safe_Last
=>
5687 Check_Floating_Point_Type_0
;
5688 Set_Etype
(N
, Universal_Real
);
5694 when Attribute_Safe_Small
=>
5697 Set_Etype
(N
, Universal_Real
);
5699 --------------------------
5700 -- Scalar_Storage_Order --
5701 --------------------------
5703 when Attribute_Scalar_Storage_Order
=> Scalar_Storage_Order
: declare
5704 Ent
: Entity_Id
:= Empty
;
5710 if not (Is_Record_Type
(P_Type
) or else Is_Array_Type
(P_Type
)) then
5712 -- In GNAT mode, the attribute applies to generic types as well
5713 -- as composite types, and for non-composite types always returns
5714 -- the default bit order for the target.
5716 if not (GNAT_Mode
and then Is_Generic_Type
(P_Type
))
5717 and then not In_Instance
5720 ("prefix of % attribute must be record or array type");
5722 elsif not Is_Generic_Type
(P_Type
) then
5723 if Bytes_Big_Endian
then
5724 Ent
:= RTE
(RE_High_Order_First
);
5726 Ent
:= RTE
(RE_Low_Order_First
);
5730 elsif Bytes_Big_Endian
xor Reverse_Storage_Order
(P_Type
) then
5731 Ent
:= RTE
(RE_High_Order_First
);
5734 Ent
:= RTE
(RE_Low_Order_First
);
5737 if Present
(Ent
) then
5738 Rewrite
(N
, New_Occurrence_Of
(Ent
, Loc
));
5741 Set_Etype
(N
, RTE
(RE_Bit_Order
));
5744 -- Reset incorrect indication of staticness
5746 Set_Is_Static_Expression
(N
, False);
5747 end Scalar_Storage_Order
;
5753 when Attribute_Scale
=>
5755 Check_Decimal_Fixed_Point_Type
;
5756 Set_Etype
(N
, Universal_Integer
);
5762 when Attribute_Scaling
=>
5763 Check_Floating_Point_Type_2
;
5764 Set_Etype
(N
, P_Base_Type
);
5765 Resolve
(E1
, P_Base_Type
);
5771 when Attribute_Signed_Zeros
=>
5772 Check_Floating_Point_Type_0
;
5773 Set_Etype
(N
, Standard_Boolean
);
5780 | Attribute_VADS_Size
5784 -- If prefix is parameterless function call, rewrite and resolve
5787 if Is_Entity_Name
(P
)
5788 and then Ekind
(Entity
(P
)) = E_Function
5792 -- Similar processing for a protected function call
5794 elsif Nkind
(P
) = N_Selected_Component
5795 and then Ekind
(Entity
(Selector_Name
(P
))) = E_Function
5800 if Is_Object_Reference
(P
) then
5801 Check_Object_Reference
(P
);
5803 elsif Is_Entity_Name
(P
)
5804 and then (Is_Type
(Entity
(P
))
5805 or else Ekind
(Entity
(P
)) = E_Enumeration_Literal
)
5809 elsif Nkind
(P
) = N_Type_Conversion
5810 and then not Comes_From_Source
(P
)
5814 -- Some other compilers allow dubious use of X'???'Size
5816 elsif Relaxed_RM_Semantics
5817 and then Nkind
(P
) = N_Attribute_Reference
5822 Error_Attr_P
("invalid prefix for % attribute");
5825 Check_Not_Incomplete_Type
;
5827 Set_Etype
(N
, Universal_Integer
);
5829 -- If we are processing pragmas Compile_Time_Warning and Compile_
5830 -- Time_Errors after the back end has been called and this occurrence
5831 -- of 'Size is known at compile time then it is safe to perform this
5832 -- evaluation. Needed to perform the static evaluation of the full
5833 -- boolean expression of these pragmas.
5835 if In_Compile_Time_Warning_Or_Error
5836 and then Is_Entity_Name
(P
)
5837 and then (Is_Type
(Entity
(P
))
5838 or else Ekind
(Entity
(P
)) = E_Enumeration_Literal
)
5839 and then Size_Known_At_Compile_Time
(Entity
(P
))
5841 Rewrite
(N
, Make_Integer_Literal
(Sloc
(N
), Esize
(Entity
(P
))));
5849 when Attribute_Small
=>
5852 Set_Etype
(N
, Universal_Real
);
5858 when Attribute_Storage_Pool
5859 | Attribute_Simple_Storage_Pool
5863 if Is_Access_Type
(P_Type
) then
5864 if Ekind
(P_Type
) = E_Access_Subprogram_Type
then
5866 ("cannot use % attribute for access-to-subprogram type");
5869 -- Set appropriate entity
5871 if Present
(Associated_Storage_Pool
(Root_Type
(P_Type
))) then
5872 Set_Entity
(N
, Associated_Storage_Pool
(Root_Type
(P_Type
)));
5874 Set_Entity
(N
, RTE
(RE_Global_Pool_Object
));
5877 if Attr_Id
= Attribute_Storage_Pool
then
5878 if Present
(Get_Rep_Pragma
(Etype
(Entity
(N
)),
5879 Name_Simple_Storage_Pool_Type
))
5881 Error_Msg_Name_1
:= Aname
;
5882 Error_Msg_Warn
:= SPARK_Mode
/= On
;
5884 ("cannot use % attribute for type with simple storage "
5886 Error_Msg_N
("\Program_Error [<<", N
);
5889 (N
, Make_Raise_Program_Error
5890 (Sloc
(N
), Reason
=> PE_Explicit_Raise
));
5893 Set_Etype
(N
, Class_Wide_Type
(RTE
(RE_Root_Storage_Pool
)));
5895 -- In the Simple_Storage_Pool case, verify that the pool entity is
5896 -- actually of a simple storage pool type, and set the attribute's
5897 -- type to the pool object's type.
5900 if not Present
(Get_Rep_Pragma
(Etype
(Entity
(N
)),
5901 Name_Simple_Storage_Pool_Type
))
5904 ("cannot use % attribute for type without simple " &
5908 Set_Etype
(N
, Etype
(Entity
(N
)));
5911 -- Validate_Remote_Access_To_Class_Wide_Type for attribute
5912 -- Storage_Pool since this attribute is not defined for such
5913 -- types (RM E.2.3(22)).
5915 Validate_Remote_Access_To_Class_Wide_Type
(N
);
5918 Error_Attr_P
("prefix of % attribute must be access type");
5925 when Attribute_Storage_Size
=>
5928 if Is_Task_Type
(P_Type
) then
5929 Set_Etype
(N
, Universal_Integer
);
5931 -- Use with tasks is an obsolescent feature
5933 Check_Restriction
(No_Obsolescent_Features
, P
);
5935 elsif Is_Access_Type
(P_Type
) then
5936 if Ekind
(P_Type
) = E_Access_Subprogram_Type
then
5938 ("cannot use % attribute for access-to-subprogram type");
5941 if Is_Entity_Name
(P
)
5942 and then Is_Type
(Entity
(P
))
5945 Set_Etype
(N
, Universal_Integer
);
5947 -- Validate_Remote_Access_To_Class_Wide_Type for attribute
5948 -- Storage_Size since this attribute is not defined for
5949 -- such types (RM E.2.3(22)).
5951 Validate_Remote_Access_To_Class_Wide_Type
(N
);
5953 -- The prefix is allowed to be an implicit dereference of an
5954 -- access value designating a task.
5958 Set_Etype
(N
, Universal_Integer
);
5962 Error_Attr_P
("prefix of % attribute must be access or task type");
5969 when Attribute_Storage_Unit
=>
5970 Standard_Attribute
(Ttypes
.System_Storage_Unit
);
5976 when Attribute_Stream_Size
=>
5980 if Is_Entity_Name
(P
)
5981 and then Is_Elementary_Type
(Entity
(P
))
5983 Set_Etype
(N
, Universal_Integer
);
5985 Error_Attr_P
("invalid prefix for % attribute");
5992 when Attribute_Stub_Type
=>
5996 if Is_Remote_Access_To_Class_Wide_Type
(Base_Type
(P_Type
)) then
5998 -- For a real RACW [sub]type, use corresponding stub type
6000 if not Is_Generic_Type
(P_Type
) then
6003 (Corresponding_Stub_Type
(Base_Type
(P_Type
)), Loc
));
6005 -- For a generic type (that has been marked as an RACW using the
6006 -- Remote_Access_Type aspect or pragma), use a generic RACW stub
6007 -- type. Note that if the actual is not a remote access type, the
6008 -- instantiation will fail.
6011 -- Note: we go to the underlying type here because the view
6012 -- returned by RTE (RE_RACW_Stub_Type) might be incomplete.
6016 (Underlying_Type
(RTE
(RE_RACW_Stub_Type
)), Loc
));
6021 ("prefix of% attribute must be remote access-to-class-wide");
6028 when Attribute_Succ
=>
6032 if Is_Real_Type
(P_Type
) or else Is_Boolean_Type
(P_Type
) then
6033 Error_Msg_Name_1
:= Aname
;
6034 Error_Msg_Name_2
:= Chars
(P_Type
);
6035 Check_SPARK_05_Restriction
6036 ("attribute% is not allowed for type%", P
);
6039 Resolve
(E1
, P_Base_Type
);
6040 Set_Etype
(N
, P_Base_Type
);
6042 -- Since Pred works on the base type, we normally do no check for the
6043 -- floating-point case, since the base type is unconstrained. But we
6044 -- make an exception in Check_Float_Overflow mode.
6046 if Is_Floating_Point_Type
(P_Type
) then
6047 if not Range_Checks_Suppressed
(P_Base_Type
) then
6048 Set_Do_Range_Check
(E1
);
6051 -- If not modular type, test for overflow check required
6054 if not Is_Modular_Integer_Type
(P_Type
)
6055 and then not Range_Checks_Suppressed
(P_Base_Type
)
6057 Enable_Range_Check
(E1
);
6061 --------------------------------
6062 -- System_Allocator_Alignment --
6063 --------------------------------
6065 when Attribute_System_Allocator_Alignment
=>
6066 Standard_Attribute
(Ttypes
.System_Allocator_Alignment
);
6072 when Attribute_Tag
=>
6076 if not Is_Tagged_Type
(P_Type
) then
6077 Error_Attr_P
("prefix of % attribute must be tagged");
6079 -- Next test does not apply to generated code why not, and what does
6080 -- the illegal reference mean???
6082 elsif Is_Object_Reference
(P
)
6083 and then not Is_Class_Wide_Type
(P_Type
)
6084 and then Comes_From_Source
(N
)
6087 ("% attribute can only be applied to objects " &
6088 "of class - wide type");
6091 -- The prefix cannot be an incomplete type. However, references to
6092 -- 'Tag can be generated when expanding interface conversions, and
6095 if Comes_From_Source
(N
) then
6096 Check_Not_Incomplete_Type
;
6099 -- Set appropriate type
6101 Set_Etype
(N
, RTE
(RE_Tag
));
6107 when Attribute_Target_Name
=> Target_Name
: declare
6108 TN
: constant String := Sdefault
.Target_Name
.all;
6112 Check_Standard_Prefix
;
6116 if TN
(TL
) = '/' or else TN
(TL
) = '\' then
6121 Make_String_Literal
(Loc
,
6122 Strval
=> TN
(TN
'First .. TL
)));
6123 Analyze_And_Resolve
(N
, Standard_String
);
6124 Set_Is_Static_Expression
(N
, True);
6131 when Attribute_Terminated
=>
6133 Set_Etype
(N
, Standard_Boolean
);
6140 when Attribute_To_Address
=> To_Address
: declare
6146 Check_System_Prefix
;
6148 Generate_Reference
(RTE
(RE_Address
), P
);
6149 Analyze_And_Resolve
(E1
, Any_Integer
);
6150 Set_Etype
(N
, RTE
(RE_Address
));
6152 if Is_Static_Expression
(E1
) then
6153 Set_Is_Static_Expression
(N
, True);
6156 -- OK static expression case, check range and set appropriate type
6158 if Is_OK_Static_Expression
(E1
) then
6159 Val
:= Expr_Value
(E1
);
6161 if Val
< -(2 ** UI_From_Int
(Standard
'Address_Size - 1))
6163 Val
> 2 ** UI_From_Int
(Standard
'Address_Size) - 1
6165 Error_Attr
("address value out of range for % attribute", E1
);
6168 -- In most cases the expression is a numeric literal or some other
6169 -- address expression, but if it is a declared constant it may be
6170 -- of a compatible type that must be left on the node.
6172 if Is_Entity_Name
(E1
) then
6175 -- Set type to universal integer if negative
6178 Set_Etype
(E1
, Universal_Integer
);
6180 -- Otherwise set type to Unsigned_64 to accommodate max values
6183 Set_Etype
(E1
, Standard_Unsigned_64
);
6187 Set_Is_Static_Expression
(N
, True);
6194 when Attribute_To_Any
=>
6196 Check_PolyORB_Attribute
;
6197 Set_Etype
(N
, RTE
(RE_Any
));
6203 when Attribute_Truncation
=>
6204 Check_Floating_Point_Type_1
;
6205 Resolve
(E1
, P_Base_Type
);
6206 Set_Etype
(N
, P_Base_Type
);
6212 when Attribute_Type_Class
=>
6215 Check_Not_Incomplete_Type
;
6216 Set_Etype
(N
, RTE
(RE_Type_Class
));
6222 when Attribute_TypeCode
=>
6224 Check_PolyORB_Attribute
;
6225 Set_Etype
(N
, RTE
(RE_TypeCode
));
6231 when Attribute_Type_Key
=> Type_Key
: declare
6232 Full_Name
: constant String_Id
:=
6233 Fully_Qualified_Name_String
(Entity
(P
));
6236 -- The computed signature for the type
6239 -- To simplify the handling of mutually recursive types, follow a
6240 -- single dereference link in a composite type.
6242 procedure Compute_Type_Key
(T
: Entity_Id
);
6243 -- Create a CRC integer from the declaration of the type. For a
6244 -- composite type, fold in the representation of its components in
6245 -- recursive fashion. We use directly the source representation of
6246 -- the types involved.
6248 ----------------------
6249 -- Compute_Type_Key --
6250 ----------------------
6252 procedure Compute_Type_Key
(T
: Entity_Id
) is
6253 Buffer
: Source_Buffer_Ptr
;
6257 SFI
: Source_File_Index
;
6259 procedure Process_One_Declaration
;
6260 -- Update CRC with the characters of one type declaration, or a
6261 -- representation pragma that applies to the type.
6263 -----------------------------
6264 -- Process_One_Declaration --
6265 -----------------------------
6267 procedure Process_One_Declaration
is
6269 -- Scan type declaration, skipping blanks
6271 for Ptr
in P_Min
.. P_Max
loop
6272 if Buffer
(Ptr
) /= ' ' then
6273 System
.CRC32
.Update
(CRC
, Buffer
(Ptr
));
6276 end Process_One_Declaration
;
6278 -- Start of processing for Compute_Type_Key
6281 if Is_Itype
(T
) then
6285 -- If the type is declared in Standard, there is no source, so
6286 -- just use its name.
6288 if Scope
(T
) = Standard_Standard
then
6290 Name
: constant String := Get_Name_String
(Chars
(T
));
6292 for J
in Name
'Range loop
6293 System
.CRC32
.Update
(CRC
, Name
(J
));
6300 Sloc_Range
(Enclosing_Declaration
(T
), P_Min
, P_Max
);
6301 SFI
:= Get_Source_File_Index
(P_Min
);
6302 pragma Assert
(SFI
= Get_Source_File_Index
(P_Max
));
6303 Buffer
:= Source_Text
(SFI
);
6305 Process_One_Declaration
;
6307 -- Recurse on relevant component types
6309 if Is_Array_Type
(T
) then
6310 Compute_Type_Key
(Component_Type
(T
));
6312 elsif Is_Access_Type
(T
) then
6315 Compute_Type_Key
(Designated_Type
(T
));
6318 elsif Is_Derived_Type
(T
) then
6319 Compute_Type_Key
(Etype
(T
));
6321 elsif Is_Record_Type
(T
) then
6325 Comp
:= First_Component
(T
);
6326 while Present
(Comp
) loop
6327 Compute_Type_Key
(Etype
(Comp
));
6328 Next_Component
(Comp
);
6333 if Is_First_Subtype
(T
) then
6335 -- Fold in representation aspects for the type, which appear in
6336 -- the same source buffer. If the representation aspects are in
6337 -- a different source file, then skip them; they apply to some
6338 -- other type, perhaps one we're derived from.
6340 Rep
:= First_Rep_Item
(T
);
6342 while Present
(Rep
) loop
6343 if Comes_From_Source
(Rep
) then
6344 Sloc_Range
(Rep
, P_Min
, P_Max
);
6346 if SFI
= Get_Source_File_Index
(P_Min
) then
6347 pragma Assert
(SFI
= Get_Source_File_Index
(P_Max
));
6348 Process_One_Declaration
;
6352 Rep
:= Next_Rep_Item
(Rep
);
6355 end Compute_Type_Key
;
6357 -- Start of processing for Type_Key
6366 -- Copy all characters in Full_Name but the trailing NUL
6368 for J
in 1 .. String_Length
(Full_Name
) - 1 loop
6369 Store_String_Char
(Get_String_Char
(Full_Name
, Pos
(J
)));
6372 -- Compute CRC and convert it to string one character at a time, so
6373 -- as not to use Image within the compiler.
6376 Compute_Type_Key
(Entity
(P
));
6378 if not Is_Frozen
(Entity
(P
)) then
6379 Error_Msg_N
("premature usage of Type_Key?", N
);
6383 Store_String_Char
(Character'Val (48 + (CRC
rem 10)));
6387 Rewrite
(N
, Make_String_Literal
(Loc
, End_String
));
6388 Analyze_And_Resolve
(N
, Standard_String
);
6391 -----------------------
6392 -- Unbiased_Rounding --
6393 -----------------------
6395 when Attribute_Unbiased_Rounding
=>
6396 Check_Floating_Point_Type_1
;
6397 Set_Etype
(N
, P_Base_Type
);
6398 Resolve
(E1
, P_Base_Type
);
6400 ----------------------
6401 -- Unchecked_Access --
6402 ----------------------
6404 when Attribute_Unchecked_Access
=>
6405 if Comes_From_Source
(N
) then
6406 Check_Restriction
(No_Unchecked_Access
, N
);
6409 Analyze_Access_Attribute
;
6410 Check_Not_Incomplete_Type
;
6412 -------------------------
6413 -- Unconstrained_Array --
6414 -------------------------
6416 when Attribute_Unconstrained_Array
=>
6419 Check_Not_Incomplete_Type
;
6420 Set_Etype
(N
, Standard_Boolean
);
6421 Set_Is_Static_Expression
(N
, True);
6423 ------------------------------
6424 -- Universal_Literal_String --
6425 ------------------------------
6427 -- This is a GNAT specific attribute whose prefix must be a named
6428 -- number where the expression is either a single numeric literal,
6429 -- or a numeric literal immediately preceded by a minus sign. The
6430 -- result is equivalent to a string literal containing the text of
6431 -- the literal as it appeared in the source program with a possible
6432 -- leading minus sign.
6434 when Attribute_Universal_Literal_String
=>
6437 if not Is_Entity_Name
(P
)
6438 or else Ekind
(Entity
(P
)) not in Named_Kind
6440 Error_Attr_P
("prefix for % attribute must be named number");
6447 Src
: Source_Buffer_Ptr
;
6450 Expr
:= Original_Node
(Expression
(Parent
(Entity
(P
))));
6452 if Nkind
(Expr
) = N_Op_Minus
then
6454 Expr
:= Original_Node
(Right_Opnd
(Expr
));
6459 if not Nkind_In
(Expr
, N_Integer_Literal
, N_Real_Literal
) then
6461 ("named number for % attribute must be simple literal", N
);
6464 -- Build string literal corresponding to source literal text
6469 Store_String_Char
(Get_Char_Code
('-'));
6473 Src
:= Source_Text
(Get_Source_File_Index
(S
));
6475 while Src
(S
) /= ';' and then Src
(S
) /= ' ' loop
6476 Store_String_Char
(Get_Char_Code
(Src
(S
)));
6480 -- Now we rewrite the attribute with the string literal
6483 Make_String_Literal
(Loc
, End_String
));
6485 Set_Is_Static_Expression
(N
, True);
6489 -------------------------
6490 -- Unrestricted_Access --
6491 -------------------------
6493 -- This is a GNAT specific attribute which is like Access except that
6494 -- all scope checks and checks for aliased views are omitted. It is
6495 -- documented as being equivalent to the use of the Address attribute
6496 -- followed by an unchecked conversion to the target access type.
6498 when Attribute_Unrestricted_Access
=>
6500 -- If from source, deal with relevant restrictions
6502 if Comes_From_Source
(N
) then
6503 Check_Restriction
(No_Unchecked_Access
, N
);
6505 if Nkind
(P
) in N_Has_Entity
6506 and then Present
(Entity
(P
))
6507 and then Is_Object
(Entity
(P
))
6509 Check_Restriction
(No_Implicit_Aliasing
, N
);
6513 if Is_Entity_Name
(P
) then
6514 Set_Address_Taken
(Entity
(P
));
6517 -- It might seem reasonable to call Address_Checks here to apply the
6518 -- same set of semantic checks that we enforce for 'Address (after
6519 -- all we document Unrestricted_Access as being equivalent to the
6520 -- use of Address followed by an Unchecked_Conversion). However, if
6521 -- we do enable these checks, we get multiple failures in both the
6522 -- compiler run-time and in our regression test suite, so we leave
6523 -- out these checks for now. To be investigated further some time???
6527 -- Now complete analysis using common access processing
6529 Analyze_Access_Attribute
;
6535 when Attribute_Update
=> Update
: declare
6536 Common_Typ
: Entity_Id
;
6537 -- The common type of a multiple component update for a record
6539 Comps
: Elist_Id
:= No_Elist
;
6540 -- A list used in the resolution of a record update. It contains the
6541 -- entities of all record components processed so far.
6543 procedure Analyze_Array_Component_Update
(Assoc
: Node_Id
);
6544 -- Analyze and resolve array_component_association Assoc against the
6545 -- index of array type P_Type.
6547 procedure Analyze_Record_Component_Update
(Comp
: Node_Id
);
6548 -- Analyze and resolve record_component_association Comp against
6549 -- record type P_Type.
6551 ------------------------------------
6552 -- Analyze_Array_Component_Update --
6553 ------------------------------------
6555 procedure Analyze_Array_Component_Update
(Assoc
: Node_Id
) is
6559 Index_Typ
: Entity_Id
;
6563 -- The current association contains a sequence of indexes denoting
6564 -- an element of a multidimensional array:
6566 -- (Index_1, ..., Index_N)
6568 -- Examine each individual index and resolve it against the proper
6569 -- index type of the array.
6571 if Nkind
(First
(Choices
(Assoc
))) = N_Aggregate
then
6572 Expr
:= First
(Choices
(Assoc
));
6573 while Present
(Expr
) loop
6575 -- The use of others is illegal (SPARK RM 4.4.1(12))
6577 if Nkind
(Expr
) = N_Others_Choice
then
6579 ("others choice not allowed in attribute %", Expr
);
6581 -- Otherwise analyze and resolve all indexes
6584 Index
:= First
(Expressions
(Expr
));
6585 Index_Typ
:= First_Index
(P_Type
);
6586 while Present
(Index
) and then Present
(Index_Typ
) loop
6587 Analyze_And_Resolve
(Index
, Etype
(Index_Typ
));
6589 Next_Index
(Index_Typ
);
6592 -- Detect a case where the association either lacks an
6593 -- index or contains an extra index.
6595 if Present
(Index
) or else Present
(Index_Typ
) then
6597 ("dimension mismatch in index list", Assoc
);
6604 -- The current association denotes either a single component or a
6605 -- range of components of a one dimensional array:
6609 -- Resolve the index or its high and low bounds (if range) against
6610 -- the proper index type of the array.
6613 Index
:= First
(Choices
(Assoc
));
6614 Index_Typ
:= First_Index
(P_Type
);
6616 if Present
(Next_Index
(Index_Typ
)) then
6617 Error_Msg_N
("too few subscripts in array reference", Assoc
);
6620 while Present
(Index
) loop
6622 -- The use of others is illegal (SPARK RM 4.4.1(12))
6624 if Nkind
(Index
) = N_Others_Choice
then
6626 ("others choice not allowed in attribute %", Index
);
6628 -- The index denotes a range of elements
6630 elsif Nkind
(Index
) = N_Range
then
6631 Low
:= Low_Bound
(Index
);
6632 High
:= High_Bound
(Index
);
6634 Analyze_And_Resolve
(Low
, Etype
(Index_Typ
));
6635 Analyze_And_Resolve
(High
, Etype
(Index_Typ
));
6637 -- Add a range check to ensure that the bounds of the
6638 -- range are within the index type when this cannot be
6639 -- determined statically.
6641 if not Is_OK_Static_Expression
(Low
) then
6642 Set_Do_Range_Check
(Low
);
6645 if not Is_OK_Static_Expression
(High
) then
6646 Set_Do_Range_Check
(High
);
6649 -- Otherwise the index denotes a single element
6652 Analyze_And_Resolve
(Index
, Etype
(Index_Typ
));
6654 -- Add a range check to ensure that the index is within
6655 -- the index type when it is not possible to determine
6658 if not Is_OK_Static_Expression
(Index
) then
6659 Set_Do_Range_Check
(Index
);
6666 end Analyze_Array_Component_Update
;
6668 -------------------------------------
6669 -- Analyze_Record_Component_Update --
6670 -------------------------------------
6672 procedure Analyze_Record_Component_Update
(Comp
: Node_Id
) is
6673 Comp_Name
: constant Name_Id
:= Chars
(Comp
);
6674 Base_Typ
: Entity_Id
;
6675 Comp_Or_Discr
: Entity_Id
;
6678 -- Find the discriminant or component whose name corresponds to
6679 -- Comp. A simple character comparison is sufficient because all
6680 -- visible names within a record type are unique.
6682 Comp_Or_Discr
:= First_Entity
(P_Type
);
6683 while Present
(Comp_Or_Discr
) loop
6684 if Chars
(Comp_Or_Discr
) = Comp_Name
then
6686 -- Decorate the component reference by setting its entity
6687 -- and type for resolution purposes.
6689 Set_Entity
(Comp
, Comp_Or_Discr
);
6690 Set_Etype
(Comp
, Etype
(Comp_Or_Discr
));
6694 Comp_Or_Discr
:= Next_Entity
(Comp_Or_Discr
);
6697 -- Diagnose an illegal reference
6699 if Present
(Comp_Or_Discr
) then
6700 if Ekind
(Comp_Or_Discr
) = E_Discriminant
then
6702 ("attribute % may not modify record discriminants", Comp
);
6704 else pragma Assert
(Ekind
(Comp_Or_Discr
) = E_Component
);
6705 if Contains
(Comps
, Comp_Or_Discr
) then
6706 Error_Msg_N
("component & already updated", Comp
);
6708 -- Mark this component as processed
6711 Append_New_Elmt
(Comp_Or_Discr
, Comps
);
6715 -- The update aggregate mentions an entity that does not belong to
6719 Error_Msg_N
("& is not a component of aggregate subtype", Comp
);
6722 -- Verify the consistency of types when the current component is
6723 -- part of a miltiple component update.
6725 -- Comp_1, ..., Comp_N => <value>
6727 if Present
(Etype
(Comp
)) then
6728 Base_Typ
:= Base_Type
(Etype
(Comp
));
6730 -- Save the type of the first component reference as the
6731 -- remaning references (if any) must resolve to this type.
6733 if No
(Common_Typ
) then
6734 Common_Typ
:= Base_Typ
;
6736 elsif Base_Typ
/= Common_Typ
then
6738 ("components in choice list must have same type", Comp
);
6741 end Analyze_Record_Component_Update
;
6748 -- Start of processing for Update
6753 if not Is_Object_Reference
(P
) then
6754 Error_Attr_P
("prefix of attribute % must denote an object");
6756 elsif not Is_Array_Type
(P_Type
)
6757 and then not Is_Record_Type
(P_Type
)
6759 Error_Attr_P
("prefix of attribute % must be a record or array");
6761 elsif Is_Limited_View
(P_Type
) then
6762 Error_Attr
("prefix of attribute % cannot be limited", N
);
6764 elsif Nkind
(E1
) /= N_Aggregate
then
6765 Error_Attr
("attribute % requires component association list", N
);
6768 -- Inspect the update aggregate, looking at all the associations and
6769 -- choices. Perform the following checks:
6771 -- 1) Legality of "others" in all cases
6772 -- 2) Legality of <>
6773 -- 3) Component legality for arrays
6774 -- 4) Component legality for records
6776 -- The remaining checks are performed on the expanded attribute
6778 Assoc
:= First
(Component_Associations
(E1
));
6779 while Present
(Assoc
) loop
6781 -- The use of <> is illegal (SPARK RM 4.4.1(1))
6783 if Box_Present
(Assoc
) then
6785 ("default initialization not allowed in attribute %", Assoc
);
6787 -- Otherwise process the association
6790 Analyze
(Expression
(Assoc
));
6792 if Is_Array_Type
(P_Type
) then
6793 Analyze_Array_Component_Update
(Assoc
);
6795 elsif Is_Record_Type
(P_Type
) then
6797 -- Reset the common type used in a multiple component update
6798 -- as we are processing the contents of a new association.
6800 Common_Typ
:= Empty
;
6802 Comp
:= First
(Choices
(Assoc
));
6803 while Present
(Comp
) loop
6804 if Nkind
(Comp
) = N_Identifier
then
6805 Analyze_Record_Component_Update
(Comp
);
6807 -- The use of others is illegal (SPARK RM 4.4.1(5))
6809 elsif Nkind
(Comp
) = N_Others_Choice
then
6811 ("others choice not allowed in attribute %", Comp
);
6813 -- The name of a record component cannot appear in any
6818 ("name should be identifier or OTHERS", Comp
);
6829 -- The type of attribute 'Update is that of the prefix
6831 Set_Etype
(N
, P_Type
);
6833 Sem_Warn
.Warn_On_Suspicious_Update
(N
);
6840 when Attribute_Val
=>
6842 Check_Discrete_Type
;
6844 if Is_Boolean_Type
(P_Type
) then
6845 Error_Msg_Name_1
:= Aname
;
6846 Error_Msg_Name_2
:= Chars
(P_Type
);
6847 Check_SPARK_05_Restriction
6848 ("attribute% is not allowed for type%", P
);
6851 -- Note, we need a range check in general, but we wait for the
6852 -- Resolve call to do this, since we want to let Eval_Attribute
6853 -- have a chance to find an static illegality first.
6855 Resolve
(E1
, Any_Integer
);
6856 Set_Etype
(N
, P_Base_Type
);
6862 when Attribute_Valid
=>
6865 -- Ignore check for object if we have a 'Valid reference generated
6866 -- by the expanded code, since in some cases valid checks can occur
6867 -- on items that are names, but are not objects (e.g. attributes).
6869 if Comes_From_Source
(N
) then
6870 Check_Object_Reference
(P
);
6873 if not Is_Scalar_Type
(P_Type
) then
6874 Error_Attr_P
("object for % attribute must be of scalar type");
6877 -- If the attribute appears within the subtype's own predicate
6878 -- function, then issue a warning that this will cause infinite
6882 Pred_Func
: constant Entity_Id
:= Predicate_Function
(P_Type
);
6885 if Present
(Pred_Func
) and then Current_Scope
= Pred_Func
then
6887 ("attribute Valid requires a predicate check??", N
);
6888 Error_Msg_N
("\and will result in infinite recursion??", N
);
6892 Set_Etype
(N
, Standard_Boolean
);
6898 when Attribute_Valid_Scalars
=>
6900 Check_Object_Reference
(P
);
6901 Set_Etype
(N
, Standard_Boolean
);
6903 -- Following checks are only for source types
6905 if Comes_From_Source
(N
) then
6906 if not Scalar_Part_Present
(P_Type
) then
6908 ("??attribute % always True, no scalars to check");
6911 -- Not allowed for unchecked union type
6913 if Has_Unchecked_Union
(P_Type
) then
6915 ("attribute % not allowed for Unchecked_Union type");
6923 when Attribute_Value
=>
6924 Check_SPARK_05_Restriction_On_Attribute
;
6928 -- Case of enumeration type
6930 -- When an enumeration type appears in an attribute reference, all
6931 -- literals of the type are marked as referenced. This must only be
6932 -- done if the attribute reference appears in the current source.
6933 -- Otherwise the information on references may differ between a
6934 -- normal compilation and one that performs inlining.
6936 if Is_Enumeration_Type
(P_Type
)
6937 and then In_Extended_Main_Code_Unit
(N
)
6939 Check_Restriction
(No_Enumeration_Maps
, N
);
6941 -- Mark all enumeration literals as referenced, since the use of
6942 -- the Value attribute can implicitly reference any of the
6943 -- literals of the enumeration base type.
6946 Ent
: Entity_Id
:= First_Literal
(P_Base_Type
);
6948 while Present
(Ent
) loop
6949 Set_Referenced
(Ent
);
6955 -- Set Etype before resolving expression because expansion of
6956 -- expression may require enclosing type. Note that the type
6957 -- returned by 'Value is the base type of the prefix type.
6959 Set_Etype
(N
, P_Base_Type
);
6960 Validate_Non_Static_Attribute_Function_Call
;
6962 -- Check restriction No_Fixed_IO
6964 if Restriction_Check_Required
(No_Fixed_IO
)
6965 and then Is_Fixed_Point_Type
(P_Type
)
6967 Check_Restriction
(No_Fixed_IO
, P
);
6974 when Attribute_Value_Size
=>
6977 Check_Not_Incomplete_Type
;
6978 Set_Etype
(N
, Universal_Integer
);
6984 when Attribute_Version
=>
6987 Set_Etype
(N
, RTE
(RE_Version_String
));
6993 when Attribute_Wchar_T_Size
=>
6994 Standard_Attribute
(Interfaces_Wchar_T_Size
);
7000 when Attribute_Wide_Image
=>
7001 Analyze_Image_Attribute
(Standard_Wide_String
);
7003 ---------------------
7004 -- Wide_Wide_Image --
7005 ---------------------
7007 when Attribute_Wide_Wide_Image
=>
7008 Analyze_Image_Attribute
(Standard_Wide_Wide_String
);
7014 when Attribute_Wide_Value
=>
7015 Check_SPARK_05_Restriction_On_Attribute
;
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_Value --
7035 ---------------------
7037 when Attribute_Wide_Wide_Value
=>
7041 -- Set Etype before resolving expression because expansion
7042 -- of expression may require enclosing type.
7044 Set_Etype
(N
, P_Type
);
7045 Validate_Non_Static_Attribute_Function_Call
;
7047 -- Check restriction No_Fixed_IO
7049 if Restriction_Check_Required
(No_Fixed_IO
)
7050 and then Is_Fixed_Point_Type
(P_Type
)
7052 Check_Restriction
(No_Fixed_IO
, P
);
7055 ---------------------
7056 -- Wide_Wide_Width --
7057 ---------------------
7059 when Attribute_Wide_Wide_Width
=>
7062 Set_Etype
(N
, Universal_Integer
);
7068 when Attribute_Wide_Width
=>
7069 Check_SPARK_05_Restriction_On_Attribute
;
7072 Set_Etype
(N
, Universal_Integer
);
7078 when Attribute_Width
=>
7079 Check_SPARK_05_Restriction_On_Attribute
;
7082 Set_Etype
(N
, Universal_Integer
);
7088 when Attribute_Word_Size
=>
7089 Standard_Attribute
(System_Word_Size
);
7095 when Attribute_Write
=>
7097 Check_Stream_Attribute
(TSS_Stream_Write
);
7098 Set_Etype
(N
, Standard_Void_Type
);
7099 Resolve
(N
, Standard_Void_Type
);
7103 -- In SPARK certain attributes (see below) depend on Tasking_State.
7104 -- Ensure that the entity is available for gnat2why by loading it.
7105 -- See SPARK RM 9(18) for the relevant rule.
7107 if GNATprove_Mode
then
7113 when Attribute_Callable
7116 | Attribute_Terminated
7118 Unused
:= RTE
(RE_Tasking_State
);
7126 -- All errors raise Bad_Attribute, so that we get out before any further
7127 -- damage occurs when an error is detected (for example, if we check for
7128 -- one attribute expression, and the check succeeds, we want to be able
7129 -- to proceed securely assuming that an expression is in fact present.
7131 -- Note: we set the attribute analyzed in this case to prevent any
7132 -- attempt at reanalysis which could generate spurious error msgs.
7135 when Bad_Attribute
=>
7137 Set_Etype
(N
, Any_Type
);
7139 end Analyze_Attribute
;
7141 --------------------
7142 -- Eval_Attribute --
7143 --------------------
7145 procedure Eval_Attribute
(N
: Node_Id
) is
7146 Loc
: constant Source_Ptr
:= Sloc
(N
);
7147 Aname
: constant Name_Id
:= Attribute_Name
(N
);
7148 Id
: constant Attribute_Id
:= Get_Attribute_Id
(Aname
);
7149 P
: constant Node_Id
:= Prefix
(N
);
7151 C_Type
: constant Entity_Id
:= Etype
(N
);
7152 -- The type imposed by the context
7155 -- First expression, or Empty if none
7158 -- Second expression, or Empty if none
7160 P_Entity
: Entity_Id
;
7161 -- Entity denoted by prefix
7164 -- The type of the prefix
7166 P_Base_Type
: Entity_Id
;
7167 -- The base type of the prefix type
7169 P_Root_Type
: Entity_Id
;
7170 -- The root type of the prefix type
7173 -- True if the result is Static. This is set by the general processing
7174 -- to true if the prefix is static, and all expressions are static. It
7175 -- can be reset as processing continues for particular attributes. This
7176 -- flag can still be True if the reference raises a constraint error.
7177 -- Is_Static_Expression (N) is set to follow this value as it is set
7178 -- and we could always reference this, but it is convenient to have a
7179 -- simple short name to use, since it is frequently referenced.
7181 Lo_Bound
, Hi_Bound
: Node_Id
;
7182 -- Expressions for low and high bounds of type or array index referenced
7183 -- by First, Last, or Length attribute for array, set by Set_Bounds.
7186 -- Constraint error node used if we have an attribute reference has
7187 -- an argument that raises a constraint error. In this case we replace
7188 -- the attribute with a raise constraint_error node. This is important
7189 -- processing, since otherwise gigi might see an attribute which it is
7190 -- unprepared to deal with.
7192 procedure Check_Concurrent_Discriminant
(Bound
: Node_Id
);
7193 -- If Bound is a reference to a discriminant of a task or protected type
7194 -- occurring within the object's body, rewrite attribute reference into
7195 -- a reference to the corresponding discriminal. Use for the expansion
7196 -- of checks against bounds of entry family index subtypes.
7198 procedure Check_Expressions
;
7199 -- In case where the attribute is not foldable, the expressions, if
7200 -- any, of the attribute, are in a non-static context. This procedure
7201 -- performs the required additional checks.
7203 function Compile_Time_Known_Bounds
(Typ
: Entity_Id
) return Boolean;
7204 -- Determines if the given type has compile time known bounds. Note
7205 -- that we enter the case statement even in cases where the prefix
7206 -- type does NOT have known bounds, so it is important to guard any
7207 -- attempt to evaluate both bounds with a call to this function.
7209 procedure Compile_Time_Known_Attribute
(N
: Node_Id
; Val
: Uint
);
7210 -- This procedure is called when the attribute N has a non-static
7211 -- but compile time known value given by Val. It includes the
7212 -- necessary checks for out of range values.
7214 function Fore_Value
return Nat
;
7215 -- Computes the Fore value for the current attribute prefix, which is
7216 -- known to be a static fixed-point type. Used by Fore and Width.
7218 function Mantissa
return Uint
;
7219 -- Returns the Mantissa value for the prefix type
7221 procedure Set_Bounds
;
7222 -- Used for First, Last and Length attributes applied to an array or
7223 -- array subtype. Sets the variables Lo_Bound and Hi_Bound to the low
7224 -- and high bound expressions for the index referenced by the attribute
7225 -- designator (i.e. the first index if no expression is present, and the
7226 -- N'th index if the value N is present as an expression). Also used for
7227 -- First and Last of scalar types and for First_Valid and Last_Valid.
7228 -- Static is reset to False if the type or index type is not statically
7231 function Statically_Denotes_Entity
(N
: Node_Id
) return Boolean;
7232 -- Verify that the prefix of a potentially static array attribute
7233 -- satisfies the conditions of 4.9 (14).
7235 -----------------------------------
7236 -- Check_Concurrent_Discriminant --
7237 -----------------------------------
7239 procedure Check_Concurrent_Discriminant
(Bound
: Node_Id
) is
7241 -- The concurrent (task or protected) type
7244 if Nkind
(Bound
) = N_Identifier
7245 and then Ekind
(Entity
(Bound
)) = E_Discriminant
7246 and then Is_Concurrent_Record_Type
(Scope
(Entity
(Bound
)))
7248 Tsk
:= Corresponding_Concurrent_Type
(Scope
(Entity
(Bound
)));
7250 if In_Open_Scopes
(Tsk
) and then Has_Completion
(Tsk
) then
7252 -- Find discriminant of original concurrent type, and use
7253 -- its current discriminal, which is the renaming within
7254 -- the task/protected body.
7258 (Find_Body_Discriminal
(Entity
(Bound
)), Loc
));
7261 end Check_Concurrent_Discriminant
;
7263 -----------------------
7264 -- Check_Expressions --
7265 -----------------------
7267 procedure Check_Expressions
is
7271 while Present
(E
) loop
7272 Check_Non_Static_Context
(E
);
7275 end Check_Expressions
;
7277 ----------------------------------
7278 -- Compile_Time_Known_Attribute --
7279 ----------------------------------
7281 procedure Compile_Time_Known_Attribute
(N
: Node_Id
; Val
: Uint
) is
7282 T
: constant Entity_Id
:= Etype
(N
);
7285 Fold_Uint
(N
, Val
, False);
7287 -- Check that result is in bounds of the type if it is static
7289 if Is_In_Range
(N
, T
, Assume_Valid
=> False) then
7292 elsif Is_Out_Of_Range
(N
, T
) then
7293 Apply_Compile_Time_Constraint_Error
7294 (N
, "value not in range of}??", CE_Range_Check_Failed
);
7296 elsif not Range_Checks_Suppressed
(T
) then
7297 Enable_Range_Check
(N
);
7300 Set_Do_Range_Check
(N
, False);
7302 end Compile_Time_Known_Attribute
;
7304 -------------------------------
7305 -- Compile_Time_Known_Bounds --
7306 -------------------------------
7308 function Compile_Time_Known_Bounds
(Typ
: Entity_Id
) return Boolean is
7311 Compile_Time_Known_Value
(Type_Low_Bound
(Typ
))
7313 Compile_Time_Known_Value
(Type_High_Bound
(Typ
));
7314 end Compile_Time_Known_Bounds
;
7320 -- Note that the Fore calculation is based on the actual values
7321 -- of the bounds, and does not take into account possible rounding.
7323 function Fore_Value
return Nat
is
7324 Lo
: constant Uint
:= Expr_Value
(Type_Low_Bound
(P_Type
));
7325 Hi
: constant Uint
:= Expr_Value
(Type_High_Bound
(P_Type
));
7326 Small
: constant Ureal
:= Small_Value
(P_Type
);
7327 Lo_Real
: constant Ureal
:= Lo
* Small
;
7328 Hi_Real
: constant Ureal
:= Hi
* Small
;
7333 -- Bounds are given in terms of small units, so first compute
7334 -- proper values as reals.
7336 T
:= UR_Max
(abs Lo_Real
, abs Hi_Real
);
7339 -- Loop to compute proper value if more than one digit required
7341 while T
>= Ureal_10
loop
7353 -- Table of mantissa values accessed by function Computed using
7356 -- T'Mantissa = integer next above (D * log(10)/log(2)) + 1)
7358 -- where D is T'Digits (RM83 3.5.7)
7360 Mantissa_Value
: constant array (Nat
range 1 .. 40) of Nat
:= (
7402 function Mantissa
return Uint
is
7405 UI_From_Int
(Mantissa_Value
(UI_To_Int
(Digits_Value
(P_Type
))));
7412 procedure Set_Bounds
is
7418 -- For a string literal subtype, we have to construct the bounds.
7419 -- Valid Ada code never applies attributes to string literals, but
7420 -- it is convenient to allow the expander to generate attribute
7421 -- references of this type (e.g. First and Last applied to a string
7424 -- Note that the whole point of the E_String_Literal_Subtype is to
7425 -- avoid this construction of bounds, but the cases in which we
7426 -- have to materialize them are rare enough that we don't worry.
7428 -- The low bound is simply the low bound of the base type. The
7429 -- high bound is computed from the length of the string and this
7432 if Ekind
(P_Type
) = E_String_Literal_Subtype
then
7433 Ityp
:= Etype
(First_Index
(Base_Type
(P_Type
)));
7434 Lo_Bound
:= Type_Low_Bound
(Ityp
);
7437 Make_Integer_Literal
(Sloc
(P
),
7439 Expr_Value
(Lo_Bound
) + String_Literal_Length
(P_Type
) - 1);
7441 Set_Parent
(Hi_Bound
, P
);
7442 Analyze_And_Resolve
(Hi_Bound
, Etype
(Lo_Bound
));
7445 -- For non-array case, just get bounds of scalar type
7447 elsif Is_Scalar_Type
(P_Type
) then
7450 -- For a fixed-point type, we must freeze to get the attributes
7451 -- of the fixed-point type set now so we can reference them.
7453 if Is_Fixed_Point_Type
(P_Type
)
7454 and then not Is_Frozen
(Base_Type
(P_Type
))
7455 and then Compile_Time_Known_Value
(Type_Low_Bound
(P_Type
))
7456 and then Compile_Time_Known_Value
(Type_High_Bound
(P_Type
))
7458 Freeze_Fixed_Point_Type
(Base_Type
(P_Type
));
7461 -- For array case, get type of proper index
7467 Ndim
:= UI_To_Int
(Expr_Value
(E1
));
7470 Indx
:= First_Index
(P_Type
);
7471 for J
in 1 .. Ndim
- 1 loop
7475 -- If no index type, get out (some other error occurred, and
7476 -- we don't have enough information to complete the job).
7484 Ityp
:= Etype
(Indx
);
7487 -- A discrete range in an index constraint is allowed to be a
7488 -- subtype indication. This is syntactically a pain, but should
7489 -- not propagate to the entity for the corresponding index subtype.
7490 -- After checking that the subtype indication is legal, the range
7491 -- of the subtype indication should be transfered to the entity.
7492 -- The attributes for the bounds should remain the simple retrievals
7493 -- that they are now.
7495 Lo_Bound
:= Type_Low_Bound
(Ityp
);
7496 Hi_Bound
:= Type_High_Bound
(Ityp
);
7498 -- If subtype is non-static, result is definitely non-static
7500 if not Is_Static_Subtype
(Ityp
) then
7502 Set_Is_Static_Expression
(N
, False);
7504 -- Subtype is static, does it raise CE?
7506 elsif not Is_OK_Static_Subtype
(Ityp
) then
7507 Set_Raises_Constraint_Error
(N
);
7511 -------------------------------
7512 -- Statically_Denotes_Entity --
7513 -------------------------------
7515 function Statically_Denotes_Entity
(N
: Node_Id
) return Boolean is
7519 if not Is_Entity_Name
(N
) then
7526 Nkind
(Parent
(E
)) /= N_Object_Renaming_Declaration
7527 or else Statically_Denotes_Entity
(Renamed_Object
(E
));
7528 end Statically_Denotes_Entity
;
7530 -- Start of processing for Eval_Attribute
7533 -- Initialize result as non-static, will be reset if appropriate
7535 Set_Is_Static_Expression
(N
, False);
7538 -- Acquire first two expressions (at the moment, no attributes take more
7539 -- than two expressions in any case).
7541 if Present
(Expressions
(N
)) then
7542 E1
:= First
(Expressions
(N
));
7549 -- Special processing for Enabled attribute. This attribute has a very
7550 -- special prefix, and the easiest way to avoid lots of special checks
7551 -- to protect this special prefix from causing trouble is to deal with
7552 -- this attribute immediately and be done with it.
7554 if Id
= Attribute_Enabled
then
7556 -- We skip evaluation if the expander is not active. This is not just
7557 -- an optimization. It is of key importance that we not rewrite the
7558 -- attribute in a generic template, since we want to pick up the
7559 -- setting of the check in the instance, Testing Expander_Active
7560 -- might seem an easy way of doing this, but we need to account for
7561 -- ASIS needs, so check explicitly for a generic context.
7563 if not Inside_A_Generic
then
7565 C
: constant Check_Id
:= Get_Check_Id
(Chars
(P
));
7570 if C
in Predefined_Check_Id
then
7571 R
:= Scope_Suppress
.Suppress
(C
);
7573 R
:= Is_Check_Suppressed
(Empty
, C
);
7577 R
:= Is_Check_Suppressed
(Entity
(E1
), C
);
7580 Rewrite
(N
, New_Occurrence_Of
(Boolean_Literals
(not R
), Loc
));
7587 -- Attribute 'Img applied to a static enumeration value is static, and
7588 -- we will do the folding right here (things get confused if we let this
7589 -- case go through the normal circuitry).
7591 if Attribute_Name
(N
) = Name_Img
7592 and then Is_Entity_Name
(P
)
7593 and then Is_Enumeration_Type
(Etype
(Entity
(P
)))
7594 and then Is_OK_Static_Expression
(P
)
7597 Lit
: constant Entity_Id
:= Expr_Value_E
(P
);
7602 Get_Unqualified_Decoded_Name_String
(Chars
(Lit
));
7603 Set_Casing
(All_Upper_Case
);
7604 Store_String_Chars
(Name_Buffer
(1 .. Name_Len
));
7607 Rewrite
(N
, Make_String_Literal
(Loc
, Strval
=> Str
));
7608 Analyze_And_Resolve
(N
, Standard_String
);
7609 Set_Is_Static_Expression
(N
, True);
7615 -- Special processing for cases where the prefix is an object. For this
7616 -- purpose, a string literal counts as an object (attributes of string
7617 -- literals can only appear in generated code).
7619 if Is_Object_Reference
(P
) or else Nkind
(P
) = N_String_Literal
then
7621 -- For Component_Size, the prefix is an array object, and we apply
7622 -- the attribute to the type of the object. This is allowed for both
7623 -- unconstrained and constrained arrays, since the bounds have no
7624 -- influence on the value of this attribute.
7626 if Id
= Attribute_Component_Size
then
7627 P_Entity
:= Etype
(P
);
7629 -- For Enum_Rep, evaluation depends on the nature of the prefix and
7630 -- the optional argument.
7632 elsif Id
= Attribute_Enum_Rep
then
7633 if Is_Entity_Name
(P
) then
7636 Enum_Expr
: Node_Id
;
7637 -- The enumeration-type expression of interest
7642 if Ekind_In
(Entity
(P
), E_Constant
,
7643 E_Enumeration_Literal
)
7647 -- Enum_Type'Enum_Rep (E1) case
7649 elsif Is_Enumeration_Type
(Entity
(P
)) then
7652 -- Otherwise the attribute must be expanded into a
7653 -- conversion and evaluated at run time.
7660 -- We can fold if the expression is an enumeration
7661 -- literal, or if it denotes a constant whose value
7662 -- is known at compile time.
7664 if Nkind
(Enum_Expr
) in N_Has_Entity
7665 and then (Ekind
(Entity
(Enum_Expr
)) =
7666 E_Enumeration_Literal
7668 (Ekind
(Entity
(Enum_Expr
)) = E_Constant
7669 and then Nkind
(Parent
(Entity
(Enum_Expr
))) =
7670 N_Object_Declaration
7671 and then Compile_Time_Known_Value
7672 (Expression
(Parent
(Entity
(P
))))))
7674 P_Entity
:= Etype
(P
);
7681 -- Otherwise the attribute is illegal, do not attempt to perform
7682 -- any kind of folding.
7688 -- For First and Last, the prefix is an array object, and we apply
7689 -- the attribute to the type of the array, but we need a constrained
7690 -- type for this, so we use the actual subtype if available.
7692 elsif Id
= Attribute_First
or else
7693 Id
= Attribute_Last
or else
7694 Id
= Attribute_Length
7697 AS
: constant Entity_Id
:= Get_Actual_Subtype_If_Available
(P
);
7700 if Present
(AS
) and then Is_Constrained
(AS
) then
7703 -- If we have an unconstrained type we cannot fold
7711 -- For Size, give size of object if available, otherwise we
7712 -- cannot fold Size.
7714 elsif Id
= Attribute_Size
then
7715 if Is_Entity_Name
(P
)
7716 and then Known_Esize
(Entity
(P
))
7718 Compile_Time_Known_Attribute
(N
, Esize
(Entity
(P
)));
7726 -- For Alignment, give size of object if available, otherwise we
7727 -- cannot fold Alignment.
7729 elsif Id
= Attribute_Alignment
then
7730 if Is_Entity_Name
(P
)
7731 and then Known_Alignment
(Entity
(P
))
7733 Fold_Uint
(N
, Alignment
(Entity
(P
)), Static
);
7741 -- For Lock_Free, we apply the attribute to the type of the object.
7742 -- This is allowed since we have already verified that the type is a
7745 elsif Id
= Attribute_Lock_Free
then
7746 P_Entity
:= Etype
(P
);
7748 -- No other attributes for objects are folded
7755 -- Cases where P is not an object. Cannot do anything if P is not the
7756 -- name of an entity.
7758 elsif not Is_Entity_Name
(P
) then
7762 -- Otherwise get prefix entity
7765 P_Entity
:= Entity
(P
);
7768 -- If we are asked to evaluate an attribute where the prefix is a
7769 -- non-frozen generic actual type whose RM_Size is still set to zero,
7770 -- then abandon the effort.
7772 if Is_Type
(P_Entity
)
7773 and then (not Is_Frozen
(P_Entity
)
7774 and then Is_Generic_Actual_Type
(P_Entity
)
7775 and then RM_Size
(P_Entity
) = 0)
7777 -- However, the attribute Unconstrained_Array must be evaluated,
7778 -- since it is documented to be a static attribute (and can for
7779 -- example appear in a Compile_Time_Warning pragma). The frozen
7780 -- status of the type does not affect its evaluation.
7782 and then Id
/= Attribute_Unconstrained_Array
7787 -- At this stage P_Entity is the entity to which the attribute
7788 -- is to be applied. This is usually simply the entity of the
7789 -- prefix, except in some cases of attributes for objects, where
7790 -- as described above, we apply the attribute to the object type.
7792 -- Here is where we make sure that static attributes are properly
7793 -- marked as such. These are attributes whose prefix is a static
7794 -- scalar subtype, whose result is scalar, and whose arguments, if
7795 -- present, are static scalar expressions. Note that such references
7796 -- are static expressions even if they raise Constraint_Error.
7798 -- For example, Boolean'Pos (1/0 = 0) is a static expression, even
7799 -- though evaluating it raises constraint error. This means that a
7800 -- declaration like:
7802 -- X : constant := (if True then 1 else Boolean'Pos (1/0 = 0));
7804 -- is legal, since here this expression appears in a statically
7805 -- unevaluated position, so it does not actually raise an exception.
7807 if Is_Scalar_Type
(P_Entity
)
7808 and then (not Is_Generic_Type
(P_Entity
))
7809 and then Is_Static_Subtype
(P_Entity
)
7810 and then Is_Scalar_Type
(Etype
(N
))
7813 or else (Is_Static_Expression
(E1
)
7814 and then Is_Scalar_Type
(Etype
(E1
))))
7817 or else (Is_Static_Expression
(E2
)
7818 and then Is_Scalar_Type
(Etype
(E1
))))
7821 Set_Is_Static_Expression
(N
, True);
7824 -- First foldable possibility is a scalar or array type (RM 4.9(7))
7825 -- that is not generic (generic types are eliminated by RM 4.9(25)).
7826 -- Note we allow non-static non-generic types at this stage as further
7829 if Is_Type
(P_Entity
)
7830 and then (Is_Scalar_Type
(P_Entity
) or Is_Array_Type
(P_Entity
))
7831 and then (not Is_Generic_Type
(P_Entity
))
7835 -- Second foldable possibility is an array object (RM 4.9(8))
7837 elsif Ekind_In
(P_Entity
, E_Variable
, E_Constant
)
7838 and then Is_Array_Type
(Etype
(P_Entity
))
7839 and then (not Is_Generic_Type
(Etype
(P_Entity
)))
7841 P_Type
:= Etype
(P_Entity
);
7843 -- If the entity is an array constant with an unconstrained nominal
7844 -- subtype then get the type from the initial value. If the value has
7845 -- been expanded into assignments, there is no expression and the
7846 -- attribute reference remains dynamic.
7848 -- We could do better here and retrieve the type ???
7850 if Ekind
(P_Entity
) = E_Constant
7851 and then not Is_Constrained
(P_Type
)
7853 if No
(Constant_Value
(P_Entity
)) then
7856 P_Type
:= Etype
(Constant_Value
(P_Entity
));
7860 -- Definite must be folded if the prefix is not a generic type, that
7861 -- is to say if we are within an instantiation. Same processing applies
7862 -- to the GNAT attributes Atomic_Always_Lock_Free, Has_Discriminants,
7863 -- Lock_Free, Type_Class, Has_Tagged_Value, and Unconstrained_Array.
7865 elsif (Id
= Attribute_Atomic_Always_Lock_Free
or else
7866 Id
= Attribute_Definite
or else
7867 Id
= Attribute_Has_Access_Values
or else
7868 Id
= Attribute_Has_Discriminants
or else
7869 Id
= Attribute_Has_Tagged_Values
or else
7870 Id
= Attribute_Lock_Free
or else
7871 Id
= Attribute_Type_Class
or else
7872 Id
= Attribute_Unconstrained_Array
or else
7873 Id
= Attribute_Max_Alignment_For_Allocation
)
7874 and then not Is_Generic_Type
(P_Entity
)
7878 -- We can fold 'Size applied to a type if the size is known (as happens
7879 -- for a size from an attribute definition clause). At this stage, this
7880 -- can happen only for types (e.g. record types) for which the size is
7881 -- always non-static. We exclude generic types from consideration (since
7882 -- they have bogus sizes set within templates).
7884 elsif Id
= Attribute_Size
7885 and then Is_Type
(P_Entity
)
7886 and then (not Is_Generic_Type
(P_Entity
))
7887 and then Known_Static_RM_Size
(P_Entity
)
7889 Compile_Time_Known_Attribute
(N
, RM_Size
(P_Entity
));
7892 -- We can fold 'Alignment applied to a type if the alignment is known
7893 -- (as happens for an alignment from an attribute definition clause).
7894 -- At this stage, this can happen only for types (e.g. record types) for
7895 -- which the size is always non-static. We exclude generic types from
7896 -- consideration (since they have bogus sizes set within templates).
7898 elsif Id
= Attribute_Alignment
7899 and then Is_Type
(P_Entity
)
7900 and then (not Is_Generic_Type
(P_Entity
))
7901 and then Known_Alignment
(P_Entity
)
7903 Compile_Time_Known_Attribute
(N
, Alignment
(P_Entity
));
7906 -- If this is an access attribute that is known to fail accessibility
7907 -- check, rewrite accordingly.
7909 elsif Attribute_Name
(N
) = Name_Access
7910 and then Raises_Constraint_Error
(N
)
7913 Make_Raise_Program_Error
(Loc
,
7914 Reason
=> PE_Accessibility_Check_Failed
));
7915 Set_Etype
(N
, C_Type
);
7918 -- No other cases are foldable (they certainly aren't static, and at
7919 -- the moment we don't try to fold any cases other than the ones above).
7926 -- If either attribute or the prefix is Any_Type, then propagate
7927 -- Any_Type to the result and don't do anything else at all.
7929 if P_Type
= Any_Type
7930 or else (Present
(E1
) and then Etype
(E1
) = Any_Type
)
7931 or else (Present
(E2
) and then Etype
(E2
) = Any_Type
)
7933 Set_Etype
(N
, Any_Type
);
7937 -- Scalar subtype case. We have not yet enforced the static requirement
7938 -- of (RM 4.9(7)) and we don't intend to just yet, since there are cases
7939 -- of non-static attribute references (e.g. S'Digits for a non-static
7940 -- floating-point type, which we can compute at compile time).
7942 -- Note: this folding of non-static attributes is not simply a case of
7943 -- optimization. For many of the attributes affected, Gigi cannot handle
7944 -- the attribute and depends on the front end having folded them away.
7946 -- Note: although we don't require staticness at this stage, we do set
7947 -- the Static variable to record the staticness, for easy reference by
7948 -- those attributes where it matters (e.g. Succ and Pred), and also to
7949 -- be used to ensure that non-static folded things are not marked as
7950 -- being static (a check that is done right at the end).
7952 P_Root_Type
:= Root_Type
(P_Type
);
7953 P_Base_Type
:= Base_Type
(P_Type
);
7955 -- If the root type or base type is generic, then we cannot fold. This
7956 -- test is needed because subtypes of generic types are not always
7957 -- marked as being generic themselves (which seems odd???)
7959 if Is_Generic_Type
(P_Root_Type
)
7960 or else Is_Generic_Type
(P_Base_Type
)
7965 if Is_Scalar_Type
(P_Type
) then
7966 if not Is_Static_Subtype
(P_Type
) then
7968 Set_Is_Static_Expression
(N
, False);
7969 elsif not Is_OK_Static_Subtype
(P_Type
) then
7970 Set_Raises_Constraint_Error
(N
);
7973 -- Array case. We enforce the constrained requirement of (RM 4.9(7-8))
7974 -- since we can't do anything with unconstrained arrays. In addition,
7975 -- only the First, Last and Length attributes are possibly static.
7977 -- Atomic_Always_Lock_Free, Definite, Has_Access_Values,
7978 -- Has_Discriminants, Has_Tagged_Values, Lock_Free, Type_Class, and
7979 -- Unconstrained_Array are again exceptions, because they apply as well
7980 -- to unconstrained types.
7982 -- In addition Component_Size is an exception since it is possibly
7983 -- foldable, even though it is never static, and it does apply to
7984 -- unconstrained arrays. Furthermore, it is essential to fold this
7985 -- in the packed case, since otherwise the value will be incorrect.
7987 elsif Id
= Attribute_Atomic_Always_Lock_Free
or else
7988 Id
= Attribute_Definite
or else
7989 Id
= Attribute_Has_Access_Values
or else
7990 Id
= Attribute_Has_Discriminants
or else
7991 Id
= Attribute_Has_Tagged_Values
or else
7992 Id
= Attribute_Lock_Free
or else
7993 Id
= Attribute_Type_Class
or else
7994 Id
= Attribute_Unconstrained_Array
or else
7995 Id
= Attribute_Component_Size
7998 Set_Is_Static_Expression
(N
, False);
8000 elsif Id
/= Attribute_Max_Alignment_For_Allocation
then
8001 if not Is_Constrained
(P_Type
)
8002 or else (Id
/= Attribute_First
and then
8003 Id
/= Attribute_Last
and then
8004 Id
/= Attribute_Length
)
8010 -- The rules in (RM 4.9(7,8)) require a static array, but as in the
8011 -- scalar case, we hold off on enforcing staticness, since there are
8012 -- cases which we can fold at compile time even though they are not
8013 -- static (e.g. 'Length applied to a static index, even though other
8014 -- non-static indexes make the array type non-static). This is only
8015 -- an optimization, but it falls out essentially free, so why not.
8016 -- Again we compute the variable Static for easy reference later
8017 -- (note that no array attributes are static in Ada 83).
8019 -- We also need to set Static properly for subsequent legality checks
8020 -- which might otherwise accept non-static constants in contexts
8021 -- where they are not legal.
8024 Ada_Version
>= Ada_95
and then Statically_Denotes_Entity
(P
);
8025 Set_Is_Static_Expression
(N
, Static
);
8031 Nod
:= First_Index
(P_Type
);
8033 -- The expression is static if the array type is constrained
8034 -- by given bounds, and not by an initial expression. Constant
8035 -- strings are static in any case.
8037 if Root_Type
(P_Type
) /= Standard_String
then
8039 Static
and then not Is_Constr_Subt_For_U_Nominal
(P_Type
);
8040 Set_Is_Static_Expression
(N
, Static
);
8043 while Present
(Nod
) loop
8044 if not Is_Static_Subtype
(Etype
(Nod
)) then
8046 Set_Is_Static_Expression
(N
, False);
8048 elsif not Is_OK_Static_Subtype
(Etype
(Nod
)) then
8049 Set_Raises_Constraint_Error
(N
);
8051 Set_Is_Static_Expression
(N
, False);
8054 -- If however the index type is generic, or derived from
8055 -- one, attributes cannot be folded.
8057 if Is_Generic_Type
(Root_Type
(Etype
(Nod
)))
8058 and then Id
/= Attribute_Component_Size
8068 -- Check any expressions that are present. Note that these expressions,
8069 -- depending on the particular attribute type, are either part of the
8070 -- attribute designator, or they are arguments in a case where the
8071 -- attribute reference returns a function. In the latter case, the
8072 -- rule in (RM 4.9(22)) applies and in particular requires the type
8073 -- of the expressions to be scalar in order for the attribute to be
8074 -- considered to be static.
8082 while Present
(E
) loop
8084 -- If expression is not static, then the attribute reference
8085 -- result certainly cannot be static.
8087 if not Is_Static_Expression
(E
) then
8089 Set_Is_Static_Expression
(N
, False);
8092 if Raises_Constraint_Error
(E
) then
8093 Set_Raises_Constraint_Error
(N
);
8096 -- If the result is not known at compile time, or is not of
8097 -- a scalar type, then the result is definitely not static,
8098 -- so we can quit now.
8100 if not Compile_Time_Known_Value
(E
)
8101 or else not Is_Scalar_Type
(Etype
(E
))
8103 -- An odd special case, if this is a Pos attribute, this
8104 -- is where we need to apply a range check since it does
8105 -- not get done anywhere else.
8107 if Id
= Attribute_Pos
then
8108 if Is_Integer_Type
(Etype
(E
)) then
8109 Apply_Range_Check
(E
, Etype
(N
));
8116 -- If the expression raises a constraint error, then so does
8117 -- the attribute reference. We keep going in this case because
8118 -- we are still interested in whether the attribute reference
8119 -- is static even if it is not static.
8121 elsif Raises_Constraint_Error
(E
) then
8122 Set_Raises_Constraint_Error
(N
);
8128 if Raises_Constraint_Error
(Prefix
(N
)) then
8129 Set_Is_Static_Expression
(N
, False);
8134 -- Deal with the case of a static attribute reference that raises
8135 -- constraint error. The Raises_Constraint_Error flag will already
8136 -- have been set, and the Static flag shows whether the attribute
8137 -- reference is static. In any case we certainly can't fold such an
8138 -- attribute reference.
8140 -- Note that the rewriting of the attribute node with the constraint
8141 -- error node is essential in this case, because otherwise Gigi might
8142 -- blow up on one of the attributes it never expects to see.
8144 -- The constraint_error node must have the type imposed by the context,
8145 -- to avoid spurious errors in the enclosing expression.
8147 if Raises_Constraint_Error
(N
) then
8149 Make_Raise_Constraint_Error
(Sloc
(N
),
8150 Reason
=> CE_Range_Check_Failed
);
8151 Set_Etype
(CE_Node
, Etype
(N
));
8152 Set_Raises_Constraint_Error
(CE_Node
);
8154 Rewrite
(N
, Relocate_Node
(CE_Node
));
8155 Set_Raises_Constraint_Error
(N
, True);
8159 -- At this point we have a potentially foldable attribute reference.
8160 -- If Static is set, then the attribute reference definitely obeys
8161 -- the requirements in (RM 4.9(7,8,22)), and it definitely can be
8162 -- folded. If Static is not set, then the attribute may or may not
8163 -- be foldable, and the individual attribute processing routines
8164 -- test Static as required in cases where it makes a difference.
8166 -- In the case where Static is not set, we do know that all the
8167 -- expressions present are at least known at compile time (we assumed
8168 -- above that if this was not the case, then there was no hope of static
8169 -- evaluation). However, we did not require that the bounds of the
8170 -- prefix type be compile time known, let alone static). That's because
8171 -- there are many attributes that can be computed at compile time on
8172 -- non-static subtypes, even though such references are not static
8175 -- For VAX float, the root type is an IEEE type. So make sure to use the
8176 -- base type instead of the root-type for floating point attributes.
8180 -- Attributes related to Ada 2012 iterators; nothing to evaluate for
8183 when Attribute_Constant_Indexing
8184 | Attribute_Default_Iterator
8185 | Attribute_Implicit_Dereference
8186 | Attribute_Iterator_Element
8187 | Attribute_Iterable
8188 | Attribute_Variable_Indexing
8192 -- Internal attributes used to deal with Ada 2012 delayed aspects.
8193 -- These were already rejected by the parser. Thus they shouldn't
8196 when Internal_Attribute_Id
=>
8197 raise Program_Error
;
8203 when Attribute_Adjacent
=>
8207 (P_Base_Type
, Expr_Value_R
(E1
), Expr_Value_R
(E2
)),
8214 when Attribute_Aft
=>
8215 Fold_Uint
(N
, Aft_Value
(P_Type
), Static
);
8221 when Attribute_Alignment
=> Alignment_Block
: declare
8222 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
8225 -- Fold if alignment is set and not otherwise
8227 if Known_Alignment
(P_TypeA
) then
8228 Fold_Uint
(N
, Alignment
(P_TypeA
), Static
);
8230 end Alignment_Block
;
8232 -----------------------------
8233 -- Atomic_Always_Lock_Free --
8234 -----------------------------
8236 -- Atomic_Always_Lock_Free attribute is a Boolean, thus no need to fold
8239 when Attribute_Atomic_Always_Lock_Free
=> Atomic_Always_Lock_Free
:
8241 V
: constant Entity_Id
:=
8243 (Support_Atomic_Primitives_On_Target
8244 and then Support_Atomic_Primitives
(P_Type
));
8247 Rewrite
(N
, New_Occurrence_Of
(V
, Loc
));
8249 -- Analyze and resolve as boolean. Note that this attribute is a
8250 -- static attribute in GNAT.
8252 Analyze_And_Resolve
(N
, Standard_Boolean
);
8254 Set_Is_Static_Expression
(N
, True);
8255 end Atomic_Always_Lock_Free
;
8261 -- Bit can never be folded
8263 when Attribute_Bit
=>
8270 -- Body_version can never be static
8272 when Attribute_Body_Version
=>
8279 when Attribute_Ceiling
=>
8281 (N
, Eval_Fat
.Ceiling
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8283 --------------------
8284 -- Component_Size --
8285 --------------------
8287 when Attribute_Component_Size
=>
8288 if Known_Static_Component_Size
(P_Type
) then
8289 Fold_Uint
(N
, Component_Size
(P_Type
), Static
);
8296 when Attribute_Compose
=>
8299 Eval_Fat
.Compose
(P_Base_Type
, Expr_Value_R
(E1
), Expr_Value
(E2
)),
8306 -- Constrained is never folded for now, there may be cases that
8307 -- could be handled at compile time. To be looked at later.
8309 when Attribute_Constrained
=>
8311 -- The expander might fold it and set the static flag accordingly,
8312 -- but with expansion disabled (as in ASIS), it remains as an
8313 -- attribute reference, and this reference is not static.
8315 Set_Is_Static_Expression
(N
, False);
8322 when Attribute_Copy_Sign
=>
8326 (P_Base_Type
, Expr_Value_R
(E1
), Expr_Value_R
(E2
)),
8333 when Attribute_Definite
=>
8334 Rewrite
(N
, New_Occurrence_Of
(
8335 Boolean_Literals
(Is_Definite_Subtype
(P_Entity
)), Loc
));
8336 Analyze_And_Resolve
(N
, Standard_Boolean
);
8342 when Attribute_Delta
=>
8343 Fold_Ureal
(N
, Delta_Value
(P_Type
), True);
8349 when Attribute_Denorm
=>
8351 (N
, UI_From_Int
(Boolean'Pos (Has_Denormals
(P_Type
))), Static
);
8353 ---------------------
8354 -- Descriptor_Size --
8355 ---------------------
8357 when Attribute_Descriptor_Size
=>
8364 when Attribute_Digits
=>
8365 Fold_Uint
(N
, Digits_Value
(P_Type
), Static
);
8371 when Attribute_Emax
=>
8373 -- Ada 83 attribute is defined as (RM83 3.5.8)
8375 -- T'Emax = 4 * T'Mantissa
8377 Fold_Uint
(N
, 4 * Mantissa
, Static
);
8383 when Attribute_Enum_Rep
=> Enum_Rep
: declare
8387 -- The attribute appears in the form:
8389 -- Enum_Typ'Enum_Rep (Const)
8390 -- Enum_Typ'Enum_Rep (Enum_Lit)
8392 if Present
(E1
) then
8395 -- Otherwise the prefix denotes a constant or enumeration literal:
8398 -- Enum_Lit'Enum_Rep
8404 -- For an enumeration type with a non-standard representation use
8405 -- the Enumeration_Rep field of the proper constant. Note that this
8406 -- will not work for types Character/Wide_[Wide-]Character, since no
8407 -- real entities are created for the enumeration literals, but that
8408 -- does not matter since these two types do not have non-standard
8409 -- representations anyway.
8411 if Is_Enumeration_Type
(P_Type
)
8412 and then Has_Non_Standard_Rep
(P_Type
)
8414 Fold_Uint
(N
, Enumeration_Rep
(Expr_Value_E
(Val
)), Static
);
8416 -- For enumeration types with standard representations and all other
8417 -- cases (i.e. all integer and modular types), Enum_Rep is equivalent
8421 Fold_Uint
(N
, Expr_Value
(Val
), Static
);
8429 when Attribute_Enum_Val
=> Enum_Val
: declare
8433 -- We have something like Enum_Type'Enum_Val (23), so search for a
8434 -- corresponding value in the list of Enum_Rep values for the type.
8436 Lit
:= First_Literal
(P_Base_Type
);
8438 if Enumeration_Rep
(Lit
) = Expr_Value
(E1
) then
8439 Fold_Uint
(N
, Enumeration_Pos
(Lit
), Static
);
8446 Apply_Compile_Time_Constraint_Error
8447 (N
, "no representation value matches",
8448 CE_Range_Check_Failed
,
8449 Warn
=> not Static
);
8459 when Attribute_Epsilon
=>
8461 -- Ada 83 attribute is defined as (RM83 3.5.8)
8463 -- T'Epsilon = 2.0**(1 - T'Mantissa)
8465 Fold_Ureal
(N
, Ureal_2
** (1 - Mantissa
), True);
8471 when Attribute_Exponent
=>
8473 Eval_Fat
.Exponent
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8475 -----------------------
8476 -- Finalization_Size --
8477 -----------------------
8479 when Attribute_Finalization_Size
=>
8486 when Attribute_First
=>
8489 if Compile_Time_Known_Value
(Lo_Bound
) then
8490 if Is_Real_Type
(P_Type
) then
8491 Fold_Ureal
(N
, Expr_Value_R
(Lo_Bound
), Static
);
8493 Fold_Uint
(N
, Expr_Value
(Lo_Bound
), Static
);
8497 Check_Concurrent_Discriminant
(Lo_Bound
);
8504 when Attribute_First_Valid
=>
8505 if Has_Predicates
(P_Type
)
8506 and then Has_Static_Predicate
(P_Type
)
8509 FirstN
: constant Node_Id
:=
8510 First
(Static_Discrete_Predicate
(P_Type
));
8512 if Nkind
(FirstN
) = N_Range
then
8513 Fold_Uint
(N
, Expr_Value
(Low_Bound
(FirstN
)), Static
);
8515 Fold_Uint
(N
, Expr_Value
(FirstN
), Static
);
8521 Fold_Uint
(N
, Expr_Value
(Lo_Bound
), Static
);
8528 when Attribute_Fixed_Value
=>
8535 when Attribute_Floor
=>
8537 (N
, Eval_Fat
.Floor
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8543 when Attribute_Fore
=>
8544 if Compile_Time_Known_Bounds
(P_Type
) then
8545 Fold_Uint
(N
, UI_From_Int
(Fore_Value
), Static
);
8552 when Attribute_Fraction
=>
8554 (N
, Eval_Fat
.Fraction
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8556 -----------------------
8557 -- Has_Access_Values --
8558 -----------------------
8560 when Attribute_Has_Access_Values
=>
8561 Rewrite
(N
, New_Occurrence_Of
8562 (Boolean_Literals
(Has_Access_Values
(P_Root_Type
)), Loc
));
8563 Analyze_And_Resolve
(N
, Standard_Boolean
);
8565 -----------------------
8566 -- Has_Discriminants --
8567 -----------------------
8569 when Attribute_Has_Discriminants
=>
8570 Rewrite
(N
, New_Occurrence_Of
(
8571 Boolean_Literals
(Has_Discriminants
(P_Entity
)), Loc
));
8572 Analyze_And_Resolve
(N
, Standard_Boolean
);
8574 ----------------------
8575 -- Has_Same_Storage --
8576 ----------------------
8578 when Attribute_Has_Same_Storage
=>
8581 -----------------------
8582 -- Has_Tagged_Values --
8583 -----------------------
8585 when Attribute_Has_Tagged_Values
=>
8586 Rewrite
(N
, New_Occurrence_Of
8587 (Boolean_Literals
(Has_Tagged_Component
(P_Root_Type
)), Loc
));
8588 Analyze_And_Resolve
(N
, Standard_Boolean
);
8594 when Attribute_Identity
=>
8601 -- Image is a scalar attribute, but is never static, because it is
8602 -- not a static function (having a non-scalar argument (RM 4.9(22))
8603 -- However, we can constant-fold the image of an enumeration literal
8604 -- if names are available.
8606 when Attribute_Image
=>
8607 if Is_Entity_Name
(E1
)
8608 and then Ekind
(Entity
(E1
)) = E_Enumeration_Literal
8609 and then not Discard_Names
(First_Subtype
(Etype
(E1
)))
8610 and then not Global_Discard_Names
8613 Lit
: constant Entity_Id
:= Entity
(E1
);
8617 Get_Unqualified_Decoded_Name_String
(Chars
(Lit
));
8618 Set_Casing
(All_Upper_Case
);
8619 Store_String_Chars
(Name_Buffer
(1 .. Name_Len
));
8621 Rewrite
(N
, Make_String_Literal
(Loc
, Strval
=> Str
));
8622 Analyze_And_Resolve
(N
, Standard_String
);
8623 Set_Is_Static_Expression
(N
, False);
8631 -- We never try to fold Integer_Value (though perhaps we could???)
8633 when Attribute_Integer_Value
=>
8640 -- Invalid_Value is a scalar attribute that is never static, because
8641 -- the value is by design out of range.
8643 when Attribute_Invalid_Value
=>
8650 when Attribute_Large
=>
8652 -- For fixed-point, we use the identity:
8654 -- T'Large = (2.0**T'Mantissa - 1.0) * T'Small
8656 if Is_Fixed_Point_Type
(P_Type
) then
8658 Make_Op_Multiply
(Loc
,
8660 Make_Op_Subtract
(Loc
,
8664 Make_Real_Literal
(Loc
, Ureal_2
),
8666 Make_Attribute_Reference
(Loc
,
8668 Attribute_Name
=> Name_Mantissa
)),
8669 Right_Opnd
=> Make_Real_Literal
(Loc
, Ureal_1
)),
8672 Make_Real_Literal
(Loc
, Small_Value
(Entity
(P
)))));
8674 Analyze_And_Resolve
(N
, C_Type
);
8676 -- Floating-point (Ada 83 compatibility)
8679 -- Ada 83 attribute is defined as (RM83 3.5.8)
8681 -- T'Large = 2.0**T'Emax * (1.0 - 2.0**(-T'Mantissa))
8685 -- T'Emax = 4 * T'Mantissa
8689 Ureal_2
** (4 * Mantissa
) * (Ureal_1
- Ureal_2
** (-Mantissa
)),
8697 when Attribute_Lock_Free
=> Lock_Free
: declare
8698 V
: constant Entity_Id
:= Boolean_Literals
(Uses_Lock_Free
(P_Type
));
8701 Rewrite
(N
, New_Occurrence_Of
(V
, Loc
));
8703 -- Analyze and resolve as boolean. Note that this attribute is a
8704 -- static attribute in GNAT.
8706 Analyze_And_Resolve
(N
, Standard_Boolean
);
8708 Set_Is_Static_Expression
(N
, True);
8715 when Attribute_Last
=>
8718 if Compile_Time_Known_Value
(Hi_Bound
) then
8719 if Is_Real_Type
(P_Type
) then
8720 Fold_Ureal
(N
, Expr_Value_R
(Hi_Bound
), Static
);
8722 Fold_Uint
(N
, Expr_Value
(Hi_Bound
), Static
);
8726 Check_Concurrent_Discriminant
(Hi_Bound
);
8733 when Attribute_Last_Valid
=>
8734 if Has_Predicates
(P_Type
)
8735 and then Has_Static_Predicate
(P_Type
)
8738 LastN
: constant Node_Id
:=
8739 Last
(Static_Discrete_Predicate
(P_Type
));
8741 if Nkind
(LastN
) = N_Range
then
8742 Fold_Uint
(N
, Expr_Value
(High_Bound
(LastN
)), Static
);
8744 Fold_Uint
(N
, Expr_Value
(LastN
), Static
);
8750 Fold_Uint
(N
, Expr_Value
(Hi_Bound
), Static
);
8757 when Attribute_Leading_Part
=>
8760 Eval_Fat
.Leading_Part
8761 (P_Base_Type
, Expr_Value_R
(E1
), Expr_Value
(E2
)),
8768 when Attribute_Length
=> Length
: declare
8772 -- If any index type is a formal type, or derived from one, the
8773 -- bounds are not static. Treating them as static can produce
8774 -- spurious warnings or improper constant folding.
8776 Ind
:= First_Index
(P_Type
);
8777 while Present
(Ind
) loop
8778 if Is_Generic_Type
(Root_Type
(Etype
(Ind
))) then
8787 -- For two compile time values, we can compute length
8789 if Compile_Time_Known_Value
(Lo_Bound
)
8790 and then Compile_Time_Known_Value
(Hi_Bound
)
8793 UI_Max
(0, 1 + (Expr_Value
(Hi_Bound
) - Expr_Value
(Lo_Bound
))),
8797 -- One more case is where Hi_Bound and Lo_Bound are compile-time
8798 -- comparable, and we can figure out the difference between them.
8801 Diff
: aliased Uint
;
8805 Compile_Time_Compare
8806 (Lo_Bound
, Hi_Bound
, Diff
'Access, Assume_Valid
=> False)
8809 Fold_Uint
(N
, Uint_1
, Static
);
8812 Fold_Uint
(N
, Uint_0
, Static
);
8815 if Diff
/= No_Uint
then
8816 Fold_Uint
(N
, Diff
+ 1, Static
);
8829 -- Loop_Entry acts as an alias of a constant initialized to the prefix
8830 -- of the said attribute at the point of entry into the related loop. As
8831 -- such, the attribute reference does not need to be evaluated because
8832 -- the prefix is the one that is evaluted.
8834 when Attribute_Loop_Entry
=>
8841 when Attribute_Machine
=>
8845 (P_Base_Type
, Expr_Value_R
(E1
), Eval_Fat
.Round
, N
),
8852 when Attribute_Machine_Emax
=>
8853 Fold_Uint
(N
, Machine_Emax_Value
(P_Type
), Static
);
8859 when Attribute_Machine_Emin
=>
8860 Fold_Uint
(N
, Machine_Emin_Value
(P_Type
), Static
);
8862 ----------------------
8863 -- Machine_Mantissa --
8864 ----------------------
8866 when Attribute_Machine_Mantissa
=>
8867 Fold_Uint
(N
, Machine_Mantissa_Value
(P_Type
), Static
);
8869 -----------------------
8870 -- Machine_Overflows --
8871 -----------------------
8873 when Attribute_Machine_Overflows
=>
8875 -- Always true for fixed-point
8877 if Is_Fixed_Point_Type
(P_Type
) then
8878 Fold_Uint
(N
, True_Value
, Static
);
8880 -- Floating point case
8884 UI_From_Int
(Boolean'Pos (Machine_Overflows_On_Target
)),
8892 when Attribute_Machine_Radix
=>
8893 if Is_Fixed_Point_Type
(P_Type
) then
8894 if Is_Decimal_Fixed_Point_Type
(P_Type
)
8895 and then Machine_Radix_10
(P_Type
)
8897 Fold_Uint
(N
, Uint_10
, Static
);
8899 Fold_Uint
(N
, Uint_2
, Static
);
8902 -- All floating-point type always have radix 2
8905 Fold_Uint
(N
, Uint_2
, Static
);
8908 ----------------------
8909 -- Machine_Rounding --
8910 ----------------------
8912 -- Note: for the folding case, it is fine to treat Machine_Rounding
8913 -- exactly the same way as Rounding, since this is one of the allowed
8914 -- behaviors, and performance is not an issue here. It might be a bit
8915 -- better to give the same result as it would give at run time, even
8916 -- though the non-determinism is certainly permitted.
8918 when Attribute_Machine_Rounding
=>
8920 (N
, Eval_Fat
.Rounding
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8922 --------------------
8923 -- Machine_Rounds --
8924 --------------------
8926 when Attribute_Machine_Rounds
=>
8928 -- Always False for fixed-point
8930 if Is_Fixed_Point_Type
(P_Type
) then
8931 Fold_Uint
(N
, False_Value
, Static
);
8933 -- Else yield proper floating-point result
8937 (N
, UI_From_Int
(Boolean'Pos (Machine_Rounds_On_Target
)),
8945 -- Note: Machine_Size is identical to Object_Size
8947 when Attribute_Machine_Size
=> Machine_Size
: declare
8948 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
8951 if Known_Esize
(P_TypeA
) then
8952 Fold_Uint
(N
, Esize
(P_TypeA
), Static
);
8960 when Attribute_Mantissa
=>
8962 -- Fixed-point mantissa
8964 if Is_Fixed_Point_Type
(P_Type
) then
8966 -- Compile time foldable case
8968 if Compile_Time_Known_Value
(Type_Low_Bound
(P_Type
))
8970 Compile_Time_Known_Value
(Type_High_Bound
(P_Type
))
8972 -- The calculation of the obsolete Ada 83 attribute Mantissa
8973 -- is annoying, because of AI00143, quoted here:
8975 -- !question 84-01-10
8977 -- Consider the model numbers for F:
8979 -- type F is delta 1.0 range -7.0 .. 8.0;
8981 -- The wording requires that F'MANTISSA be the SMALLEST
8982 -- integer number for which each bound of the specified
8983 -- range is either a model number or lies at most small
8984 -- distant from a model number. This means F'MANTISSA
8985 -- is required to be 3 since the range -7.0 .. 7.0 fits
8986 -- in 3 signed bits, and 8 is "at most" 1.0 from a model
8987 -- number, namely, 7. Is this analysis correct? Note that
8988 -- this implies the upper bound of the range is not
8989 -- represented as a model number.
8991 -- !response 84-03-17
8993 -- The analysis is correct. The upper and lower bounds for
8994 -- a fixed point type can lie outside the range of model
9005 LBound
:= Expr_Value_R
(Type_Low_Bound
(P_Type
));
9006 UBound
:= Expr_Value_R
(Type_High_Bound
(P_Type
));
9007 Bound
:= UR_Max
(UR_Abs
(LBound
), UR_Abs
(UBound
));
9008 Max_Man
:= UR_Trunc
(Bound
/ Small_Value
(P_Type
));
9010 -- If the Bound is exactly a model number, i.e. a multiple
9011 -- of Small, then we back it off by one to get the integer
9012 -- value that must be representable.
9014 if Small_Value
(P_Type
) * Max_Man
= Bound
then
9015 Max_Man
:= Max_Man
- 1;
9018 -- Now find corresponding size = Mantissa value
9021 while 2 ** Siz
< Max_Man
loop
9025 Fold_Uint
(N
, Siz
, Static
);
9029 -- The case of dynamic bounds cannot be evaluated at compile
9030 -- time. Instead we use a runtime routine (see Exp_Attr).
9035 -- Floating-point Mantissa
9038 Fold_Uint
(N
, Mantissa
, Static
);
9045 when Attribute_Max
=>
9046 if Is_Real_Type
(P_Type
) then
9048 (N
, UR_Max
(Expr_Value_R
(E1
), Expr_Value_R
(E2
)), Static
);
9050 Fold_Uint
(N
, UI_Max
(Expr_Value
(E1
), Expr_Value
(E2
)), Static
);
9053 ----------------------------------
9054 -- Max_Alignment_For_Allocation --
9055 ----------------------------------
9057 -- Max_Alignment_For_Allocation is usually the Alignment. However,
9058 -- arrays are allocated with dope, so we need to take into account both
9059 -- the alignment of the array, which comes from the component alignment,
9060 -- and the alignment of the dope. Also, if the alignment is unknown, we
9061 -- use the max (it's OK to be pessimistic).
9063 when Attribute_Max_Alignment_For_Allocation
=> Max_Align
: declare
9064 A
: Uint
:= UI_From_Int
(Ttypes
.Maximum_Alignment
);
9066 if Known_Alignment
(P_Type
)
9067 and then (not Is_Array_Type
(P_Type
) or else Alignment
(P_Type
) > A
)
9069 A
:= Alignment
(P_Type
);
9072 Fold_Uint
(N
, A
, Static
);
9075 ----------------------------------
9076 -- Max_Size_In_Storage_Elements --
9077 ----------------------------------
9079 -- Max_Size_In_Storage_Elements is simply the Size rounded up to a
9080 -- Storage_Unit boundary. We can fold any cases for which the size
9081 -- is known by the front end.
9083 when Attribute_Max_Size_In_Storage_Elements
=>
9084 if Known_Esize
(P_Type
) then
9086 (Esize
(P_Type
) + System_Storage_Unit
- 1) /
9087 System_Storage_Unit
,
9091 --------------------
9092 -- Mechanism_Code --
9093 --------------------
9095 when Attribute_Mechanism_Code
=> Mechanism_Code
: declare
9097 Mech
: Mechanism_Type
;
9102 Mech
:= Mechanism
(P_Entity
);
9105 Val
:= UI_To_Int
(Expr_Value
(E1
));
9107 Formal
:= First_Formal
(P_Entity
);
9108 for J
in 1 .. Val
- 1 loop
9109 Next_Formal
(Formal
);
9112 Mech
:= Mechanism
(Formal
);
9116 Fold_Uint
(N
, UI_From_Int
(Int
(-Mech
)), Static
);
9124 when Attribute_Min
=>
9125 if Is_Real_Type
(P_Type
) then
9127 (N
, UR_Min
(Expr_Value_R
(E1
), Expr_Value_R
(E2
)), Static
);
9130 (N
, UI_Min
(Expr_Value
(E1
), Expr_Value
(E2
)), Static
);
9137 when Attribute_Mod
=>
9139 (N
, UI_Mod
(Expr_Value
(E1
), Modulus
(P_Base_Type
)), Static
);
9145 when Attribute_Model
=>
9147 (N
, Eval_Fat
.Model
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
9153 when Attribute_Model_Emin
=>
9154 Fold_Uint
(N
, Model_Emin_Value
(P_Base_Type
), Static
);
9160 when Attribute_Model_Epsilon
=>
9161 Fold_Ureal
(N
, Model_Epsilon_Value
(P_Base_Type
), Static
);
9163 --------------------
9164 -- Model_Mantissa --
9165 --------------------
9167 when Attribute_Model_Mantissa
=>
9168 Fold_Uint
(N
, Model_Mantissa_Value
(P_Base_Type
), Static
);
9174 when Attribute_Model_Small
=>
9175 Fold_Ureal
(N
, Model_Small_Value
(P_Base_Type
), Static
);
9181 when Attribute_Modulus
=>
9182 Fold_Uint
(N
, Modulus
(P_Type
), Static
);
9184 --------------------
9185 -- Null_Parameter --
9186 --------------------
9188 -- Cannot fold, we know the value sort of, but the whole point is
9189 -- that there is no way to talk about this imaginary value except
9190 -- by using the attribute, so we leave it the way it is.
9192 when Attribute_Null_Parameter
=>
9199 -- The Object_Size attribute for a type returns the Esize of the
9200 -- type and can be folded if this value is known.
9202 when Attribute_Object_Size
=> Object_Size
: declare
9203 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
9206 if Known_Esize
(P_TypeA
) then
9207 Fold_Uint
(N
, Esize
(P_TypeA
), Static
);
9211 ----------------------
9212 -- Overlaps_Storage --
9213 ----------------------
9215 when Attribute_Overlaps_Storage
=>
9218 -------------------------
9219 -- Passed_By_Reference --
9220 -------------------------
9222 -- Scalar types are never passed by reference
9224 when Attribute_Passed_By_Reference
=>
9225 Fold_Uint
(N
, False_Value
, Static
);
9231 when Attribute_Pos
=>
9232 Fold_Uint
(N
, Expr_Value
(E1
), Static
);
9238 when Attribute_Pred
=>
9240 -- Floating-point case
9242 if Is_Floating_Point_Type
(P_Type
) then
9244 (N
, Eval_Fat
.Pred
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
9248 elsif Is_Fixed_Point_Type
(P_Type
) then
9250 (N
, Expr_Value_R
(E1
) - Small_Value
(P_Type
), True);
9252 -- Modular integer case (wraps)
9254 elsif Is_Modular_Integer_Type
(P_Type
) then
9255 Fold_Uint
(N
, (Expr_Value
(E1
) - 1) mod Modulus
(P_Type
), Static
);
9257 -- Other scalar cases
9260 pragma Assert
(Is_Scalar_Type
(P_Type
));
9262 if Is_Enumeration_Type
(P_Type
)
9263 and then Expr_Value
(E1
) =
9264 Expr_Value
(Type_Low_Bound
(P_Base_Type
))
9266 Apply_Compile_Time_Constraint_Error
9267 (N
, "Pred of `&''First`",
9268 CE_Overflow_Check_Failed
,
9270 Warn
=> not Static
);
9276 Fold_Uint
(N
, Expr_Value
(E1
) - 1, Static
);
9283 -- No processing required, because by this stage, Range has been
9284 -- replaced by First .. Last, so this branch can never be taken.
9286 when Attribute_Range
=>
9287 raise Program_Error
;
9293 when Attribute_Range_Length
=> Range_Length
: declare
9294 Diff
: aliased Uint
;
9299 -- Can fold if both bounds are compile time known
9301 if Compile_Time_Known_Value
(Hi_Bound
)
9302 and then Compile_Time_Known_Value
(Lo_Bound
)
9306 (0, Expr_Value
(Hi_Bound
) - Expr_Value
(Lo_Bound
) + 1),
9310 -- One more case is where Hi_Bound and Lo_Bound are compile-time
9311 -- comparable, and we can figure out the difference between them.
9313 case Compile_Time_Compare
9314 (Lo_Bound
, Hi_Bound
, Diff
'Access, Assume_Valid
=> False)
9317 Fold_Uint
(N
, Uint_1
, Static
);
9320 Fold_Uint
(N
, Uint_0
, Static
);
9323 if Diff
/= No_Uint
then
9324 Fold_Uint
(N
, Diff
+ 1, Static
);
9336 when Attribute_Ref
=>
9337 Fold_Uint
(N
, Expr_Value
(E1
), Static
);
9343 when Attribute_Remainder
=> Remainder
: declare
9344 X
: constant Ureal
:= Expr_Value_R
(E1
);
9345 Y
: constant Ureal
:= Expr_Value_R
(E2
);
9348 if UR_Is_Zero
(Y
) then
9349 Apply_Compile_Time_Constraint_Error
9350 (N
, "division by zero in Remainder",
9351 CE_Overflow_Check_Failed
,
9352 Warn
=> not Static
);
9358 Fold_Ureal
(N
, Eval_Fat
.Remainder
(P_Base_Type
, X
, Y
), Static
);
9365 when Attribute_Restriction_Set
=>
9366 Rewrite
(N
, New_Occurrence_Of
(Standard_False
, Loc
));
9367 Set_Is_Static_Expression
(N
);
9373 when Attribute_Round
=> Round
: declare
9378 -- First we get the (exact result) in units of small
9380 Sr
:= Expr_Value_R
(E1
) / Small_Value
(C_Type
);
9382 -- Now round that exactly to an integer
9384 Si
:= UR_To_Uint
(Sr
);
9386 -- Finally the result is obtained by converting back to real
9388 Fold_Ureal
(N
, Si
* Small_Value
(C_Type
), Static
);
9395 when Attribute_Rounding
=>
9397 (N
, Eval_Fat
.Rounding
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
9403 when Attribute_Safe_Emax
=>
9404 Fold_Uint
(N
, Safe_Emax_Value
(P_Type
), Static
);
9410 when Attribute_Safe_First
=>
9411 Fold_Ureal
(N
, Safe_First_Value
(P_Type
), Static
);
9417 when Attribute_Safe_Large
=>
9418 if Is_Fixed_Point_Type
(P_Type
) then
9420 (N
, Expr_Value_R
(Type_High_Bound
(P_Base_Type
)), Static
);
9422 Fold_Ureal
(N
, Safe_Last_Value
(P_Type
), Static
);
9429 when Attribute_Safe_Last
=>
9430 Fold_Ureal
(N
, Safe_Last_Value
(P_Type
), Static
);
9436 when Attribute_Safe_Small
=>
9438 -- In Ada 95, the old Ada 83 attribute Safe_Small is redundant
9439 -- for fixed-point, since is the same as Small, but we implement
9440 -- it for backwards compatibility.
9442 if Is_Fixed_Point_Type
(P_Type
) then
9443 Fold_Ureal
(N
, Small_Value
(P_Type
), Static
);
9445 -- Ada 83 Safe_Small for floating-point cases
9448 Fold_Ureal
(N
, Model_Small_Value
(P_Type
), Static
);
9455 when Attribute_Scale
=>
9456 Fold_Uint
(N
, Scale_Value
(P_Type
), Static
);
9462 when Attribute_Scaling
=>
9466 (P_Base_Type
, Expr_Value_R
(E1
), Expr_Value
(E2
)),
9473 when Attribute_Signed_Zeros
=>
9475 (N
, UI_From_Int
(Boolean'Pos (Has_Signed_Zeros
(P_Type
))), Static
);
9481 -- Size attribute returns the RM size. All scalar types can be folded,
9482 -- as well as any types for which the size is known by the front end,
9483 -- including any type for which a size attribute is specified. This is
9484 -- one of the places where it is annoying that a size of zero means two
9485 -- things (zero size for scalars, unspecified size for non-scalars).
9488 | Attribute_VADS_Size
9491 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
9494 if Is_Scalar_Type
(P_TypeA
)
9495 or else RM_Size
(P_TypeA
) /= Uint_0
9499 if Id
= Attribute_VADS_Size
or else Use_VADS_Size
then
9501 S
: constant Node_Id
:= Size_Clause
(P_TypeA
);
9504 -- If a size clause applies, then use the size from it.
9505 -- This is one of the rare cases where we can use the
9506 -- Size_Clause field for a subtype when Has_Size_Clause
9507 -- is False. Consider:
9509 -- type x is range 1 .. 64;
9510 -- for x'size use 12;
9511 -- subtype y is x range 0 .. 3;
9513 -- Here y has a size clause inherited from x, but
9514 -- normally it does not apply, and y'size is 2. However,
9515 -- y'VADS_Size is indeed 12 and not 2.
9518 and then Is_OK_Static_Expression
(Expression
(S
))
9520 Fold_Uint
(N
, Expr_Value
(Expression
(S
)), Static
);
9522 -- If no size is specified, then we simply use the object
9523 -- size in the VADS_Size case (e.g. Natural'Size is equal
9524 -- to Integer'Size, not one less).
9527 Fold_Uint
(N
, Esize
(P_TypeA
), Static
);
9531 -- Normal case (Size) in which case we want the RM_Size
9534 Fold_Uint
(N
, RM_Size
(P_TypeA
), Static
);
9543 when Attribute_Small
=>
9545 -- The floating-point case is present only for Ada 83 compatibility.
9546 -- Note that strictly this is an illegal addition, since we are
9547 -- extending an Ada 95 defined attribute, but we anticipate an
9548 -- ARG ruling that will permit this.
9550 if Is_Floating_Point_Type
(P_Type
) then
9552 -- Ada 83 attribute is defined as (RM83 3.5.8)
9554 -- T'Small = 2.0**(-T'Emax - 1)
9558 -- T'Emax = 4 * T'Mantissa
9560 Fold_Ureal
(N
, Ureal_2
** ((-(4 * Mantissa
)) - 1), Static
);
9562 -- Normal Ada 95 fixed-point case
9565 Fold_Ureal
(N
, Small_Value
(P_Type
), True);
9572 when Attribute_Stream_Size
=>
9579 when Attribute_Succ
=>
9580 -- Floating-point case
9582 if Is_Floating_Point_Type
(P_Type
) then
9584 (N
, Eval_Fat
.Succ
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
9588 elsif Is_Fixed_Point_Type
(P_Type
) then
9589 Fold_Ureal
(N
, Expr_Value_R
(E1
) + Small_Value
(P_Type
), Static
);
9591 -- Modular integer case (wraps)
9593 elsif Is_Modular_Integer_Type
(P_Type
) then
9594 Fold_Uint
(N
, (Expr_Value
(E1
) + 1) mod Modulus
(P_Type
), Static
);
9596 -- Other scalar cases
9599 pragma Assert
(Is_Scalar_Type
(P_Type
));
9601 if Is_Enumeration_Type
(P_Type
)
9602 and then Expr_Value
(E1
) =
9603 Expr_Value
(Type_High_Bound
(P_Base_Type
))
9605 Apply_Compile_Time_Constraint_Error
9606 (N
, "Succ of `&''Last`",
9607 CE_Overflow_Check_Failed
,
9609 Warn
=> not Static
);
9614 Fold_Uint
(N
, Expr_Value
(E1
) + 1, Static
);
9622 when Attribute_Truncation
=>
9625 Eval_Fat
.Truncation
(P_Base_Type
, Expr_Value_R
(E1
)),
9632 when Attribute_Type_Class
=> Type_Class
: declare
9633 Typ
: constant Entity_Id
:= Underlying_Type
(P_Base_Type
);
9637 if Is_Descendant_Of_Address
(Typ
) then
9638 Id
:= RE_Type_Class_Address
;
9640 elsif Is_Enumeration_Type
(Typ
) then
9641 Id
:= RE_Type_Class_Enumeration
;
9643 elsif Is_Integer_Type
(Typ
) then
9644 Id
:= RE_Type_Class_Integer
;
9646 elsif Is_Fixed_Point_Type
(Typ
) then
9647 Id
:= RE_Type_Class_Fixed_Point
;
9649 elsif Is_Floating_Point_Type
(Typ
) then
9650 Id
:= RE_Type_Class_Floating_Point
;
9652 elsif Is_Array_Type
(Typ
) then
9653 Id
:= RE_Type_Class_Array
;
9655 elsif Is_Record_Type
(Typ
) then
9656 Id
:= RE_Type_Class_Record
;
9658 elsif Is_Access_Type
(Typ
) then
9659 Id
:= RE_Type_Class_Access
;
9661 elsif Is_Task_Type
(Typ
) then
9662 Id
:= RE_Type_Class_Task
;
9664 -- We treat protected types like task types. It would make more
9665 -- sense to have another enumeration value, but after all the
9666 -- whole point of this feature is to be exactly DEC compatible,
9667 -- and changing the type Type_Class would not meet this requirement.
9669 elsif Is_Protected_Type
(Typ
) then
9670 Id
:= RE_Type_Class_Task
;
9672 -- Not clear if there are any other possibilities, but if there
9673 -- are, then we will treat them as the address case.
9676 Id
:= RE_Type_Class_Address
;
9679 Rewrite
(N
, New_Occurrence_Of
(RTE
(Id
), Loc
));
9682 -----------------------
9683 -- Unbiased_Rounding --
9684 -----------------------
9686 when Attribute_Unbiased_Rounding
=>
9689 Eval_Fat
.Unbiased_Rounding
(P_Base_Type
, Expr_Value_R
(E1
)),
9692 -------------------------
9693 -- Unconstrained_Array --
9694 -------------------------
9696 when Attribute_Unconstrained_Array
=> Unconstrained_Array
: declare
9697 Typ
: constant Entity_Id
:= Underlying_Type
(P_Type
);
9700 Rewrite
(N
, New_Occurrence_Of
(
9702 Is_Array_Type
(P_Type
)
9703 and then not Is_Constrained
(Typ
)), Loc
));
9705 -- Analyze and resolve as boolean, note that this attribute is
9706 -- a static attribute in GNAT.
9708 Analyze_And_Resolve
(N
, Standard_Boolean
);
9710 Set_Is_Static_Expression
(N
, True);
9711 end Unconstrained_Array
;
9713 -- Attribute Update is never static
9715 when Attribute_Update
=>
9722 -- Processing is shared with Size
9728 when Attribute_Val
=>
9729 if Expr_Value
(E1
) < Expr_Value
(Type_Low_Bound
(P_Base_Type
))
9731 Expr_Value
(E1
) > Expr_Value
(Type_High_Bound
(P_Base_Type
))
9733 Apply_Compile_Time_Constraint_Error
9734 (N
, "Val expression out of range",
9735 CE_Range_Check_Failed
,
9736 Warn
=> not Static
);
9742 Fold_Uint
(N
, Expr_Value
(E1
), Static
);
9749 -- The Value_Size attribute for a type returns the RM size of the type.
9750 -- This an always be folded for scalar types, and can also be folded for
9751 -- non-scalar types if the size is set. This is one of the places where
9752 -- it is annoying that a size of zero means two things!
9754 when Attribute_Value_Size
=> Value_Size
: declare
9755 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
9758 if Is_Scalar_Type
(P_TypeA
) or else RM_Size
(P_TypeA
) /= Uint_0
then
9759 Fold_Uint
(N
, RM_Size
(P_TypeA
), Static
);
9767 -- Version can never be static
9769 when Attribute_Version
=>
9776 -- Wide_Image is a scalar attribute, but is never static, because it
9777 -- is not a static function (having a non-scalar argument (RM 4.9(22))
9779 when Attribute_Wide_Image
=>
9782 ---------------------
9783 -- Wide_Wide_Image --
9784 ---------------------
9786 -- Wide_Wide_Image is a scalar attribute but is never static, because it
9787 -- is not a static function (having a non-scalar argument (RM 4.9(22)).
9789 when Attribute_Wide_Wide_Image
=>
9792 ---------------------
9793 -- Wide_Wide_Width --
9794 ---------------------
9796 -- Processing for Wide_Wide_Width is combined with Width
9802 -- Processing for Wide_Width is combined with Width
9808 -- This processing also handles the case of Wide_[Wide_]Width
9810 when Attribute_Width
9811 | Attribute_Wide_Width
9812 | Attribute_Wide_Wide_Width
9814 if Compile_Time_Known_Bounds
(P_Type
) then
9816 -- Floating-point types
9818 if Is_Floating_Point_Type
(P_Type
) then
9820 -- Width is zero for a null range (RM 3.5 (38))
9822 if Expr_Value_R
(Type_High_Bound
(P_Type
)) <
9823 Expr_Value_R
(Type_Low_Bound
(P_Type
))
9825 Fold_Uint
(N
, Uint_0
, Static
);
9828 -- For floating-point, we have +N.dddE+nnn where length
9829 -- of ddd is determined by type'Digits - 1, but is one
9830 -- if Digits is one (RM 3.5 (33)).
9832 -- nnn is set to 2 for Short_Float and Float (32 bit
9833 -- floats), and 3 for Long_Float and Long_Long_Float.
9834 -- For machines where Long_Long_Float is the IEEE
9835 -- extended precision type, the exponent takes 4 digits.
9839 Int
'Max (2, UI_To_Int
(Digits_Value
(P_Type
)));
9842 if Esize
(P_Type
) <= 32 then
9844 elsif Esize
(P_Type
) = 64 then
9850 Fold_Uint
(N
, UI_From_Int
(Len
), Static
);
9854 -- Fixed-point types
9856 elsif Is_Fixed_Point_Type
(P_Type
) then
9858 -- Width is zero for a null range (RM 3.5 (38))
9860 if Expr_Value
(Type_High_Bound
(P_Type
)) <
9861 Expr_Value
(Type_Low_Bound
(P_Type
))
9863 Fold_Uint
(N
, Uint_0
, Static
);
9865 -- The non-null case depends on the specific real type
9868 -- For fixed-point type width is Fore + 1 + Aft (RM 3.5(34))
9871 (N
, UI_From_Int
(Fore_Value
+ 1) + Aft_Value
(P_Type
),
9879 R
: constant Entity_Id
:= Root_Type
(P_Type
);
9880 Lo
: constant Uint
:= Expr_Value
(Type_Low_Bound
(P_Type
));
9881 Hi
: constant Uint
:= Expr_Value
(Type_High_Bound
(P_Type
));
9894 -- Width for types derived from Standard.Character
9895 -- and Standard.Wide_[Wide_]Character.
9897 elsif Is_Standard_Character_Type
(P_Type
) then
9900 -- Set W larger if needed
9902 for J
in UI_To_Int
(Lo
) .. UI_To_Int
(Hi
) loop
9904 -- All wide characters look like Hex_hhhhhhhh
9908 -- No need to compute this more than once
9913 C
:= Character'Val (J
);
9915 -- Test for all cases where Character'Image
9916 -- yields an image that is longer than three
9917 -- characters. First the cases of Reserved_xxx
9918 -- names (length = 12).
9996 | No_Break_Space
.. LC_Y_Diaeresis
9998 -- Special case of soft hyphen in Ada 2005
10000 if C
= Character'Val (16#AD#
)
10001 and then Ada_Version
>= Ada_2005
10009 W
:= Int
'Max (W
, Wt
);
10013 -- Width for types derived from Standard.Boolean
10015 elsif R
= Standard_Boolean
then
10022 -- Width for integer types
10024 elsif Is_Integer_Type
(P_Type
) then
10025 T
:= UI_Max
(abs Lo
, abs Hi
);
10033 -- User declared enum type with discard names
10035 elsif Discard_Names
(R
) then
10037 -- If range is null, result is zero, that has already
10038 -- been dealt with, so what we need is the power of ten
10039 -- that accommodates the Pos of the largest value, which
10040 -- is the high bound of the range + one for the space.
10049 -- Only remaining possibility is user declared enum type
10050 -- with normal case of Discard_Names not active.
10053 pragma Assert
(Is_Enumeration_Type
(P_Type
));
10056 L
:= First_Literal
(P_Type
);
10057 while Present
(L
) loop
10059 -- Only pay attention to in range characters
10061 if Lo
<= Enumeration_Pos
(L
)
10062 and then Enumeration_Pos
(L
) <= Hi
10064 -- For Width case, use decoded name
10066 if Id
= Attribute_Width
then
10067 Get_Decoded_Name_String
(Chars
(L
));
10068 Wt
:= Nat
(Name_Len
);
10070 -- For Wide_[Wide_]Width, use encoded name, and
10071 -- then adjust for the encoding.
10074 Get_Name_String
(Chars
(L
));
10076 -- Character literals are always of length 3
10078 if Name_Buffer
(1) = 'Q' then
10081 -- Otherwise loop to adjust for upper/wide chars
10084 Wt
:= Nat
(Name_Len
);
10086 for J
in 1 .. Name_Len
loop
10087 if Name_Buffer
(J
) = 'U' then
10089 elsif Name_Buffer
(J
) = 'W' then
10096 W
:= Int
'Max (W
, Wt
);
10103 Fold_Uint
(N
, UI_From_Int
(W
), Static
);
10108 -- The following attributes denote functions that cannot be folded
10110 when Attribute_From_Any
10112 | Attribute_TypeCode
10116 -- The following attributes can never be folded, and furthermore we
10117 -- should not even have entered the case statement for any of these.
10118 -- Note that in some cases, the values have already been folded as
10119 -- a result of the processing in Analyze_Attribute or earlier in
10122 when Attribute_Abort_Signal
10124 | Attribute_Address
10125 | Attribute_Address_Size
10126 | Attribute_Asm_Input
10127 | Attribute_Asm_Output
10129 | Attribute_Bit_Order
10130 | Attribute_Bit_Position
10131 | Attribute_Callable
10134 | Attribute_Code_Address
10135 | Attribute_Compiler_Version
10137 | Attribute_Default_Bit_Order
10138 | Attribute_Default_Scalar_Storage_Order
10140 | Attribute_Elaborated
10141 | Attribute_Elab_Body
10142 | Attribute_Elab_Spec
10143 | Attribute_Elab_Subp_Body
10144 | Attribute_Enabled
10145 | Attribute_External_Tag
10146 | Attribute_Fast_Math
10147 | Attribute_First_Bit
10150 | Attribute_Last_Bit
10151 | Attribute_Library_Level
10152 | Attribute_Maximum_Alignment
10155 | Attribute_Partition_ID
10156 | Attribute_Pool_Address
10157 | Attribute_Position
10158 | Attribute_Priority
10161 | Attribute_Scalar_Storage_Order
10162 | Attribute_Simple_Storage_Pool
10163 | Attribute_Storage_Pool
10164 | Attribute_Storage_Size
10165 | Attribute_Storage_Unit
10166 | Attribute_Stub_Type
10167 | Attribute_System_Allocator_Alignment
10169 | Attribute_Target_Name
10170 | Attribute_Terminated
10171 | Attribute_To_Address
10172 | Attribute_Type_Key
10173 | Attribute_Unchecked_Access
10174 | Attribute_Universal_Literal_String
10175 | Attribute_Unrestricted_Access
10177 | Attribute_Valid_Scalars
10179 | Attribute_Wchar_T_Size
10180 | Attribute_Wide_Value
10181 | Attribute_Wide_Wide_Value
10182 | Attribute_Word_Size
10185 raise Program_Error
;
10188 -- At the end of the case, one more check. If we did a static evaluation
10189 -- so that the result is now a literal, then set Is_Static_Expression
10190 -- in the constant only if the prefix type is a static subtype. For
10191 -- non-static subtypes, the folding is still OK, but not static.
10193 -- An exception is the GNAT attribute Constrained_Array which is
10194 -- defined to be a static attribute in all cases.
10196 if Nkind_In
(N
, N_Integer_Literal
,
10198 N_Character_Literal
,
10200 or else (Is_Entity_Name
(N
)
10201 and then Ekind
(Entity
(N
)) = E_Enumeration_Literal
)
10203 Set_Is_Static_Expression
(N
, Static
);
10205 -- If this is still an attribute reference, then it has not been folded
10206 -- and that means that its expressions are in a non-static context.
10208 elsif Nkind
(N
) = N_Attribute_Reference
then
10211 -- Note: the else case not covered here are odd cases where the
10212 -- processing has transformed the attribute into something other
10213 -- than a constant. Nothing more to do in such cases.
10218 end Eval_Attribute
;
10220 ------------------------------
10221 -- Is_Anonymous_Tagged_Base --
10222 ------------------------------
10224 function Is_Anonymous_Tagged_Base
10226 Typ
: Entity_Id
) return Boolean
10230 Anon
= Current_Scope
10231 and then Is_Itype
(Anon
)
10232 and then Associated_Node_For_Itype
(Anon
) = Parent
(Typ
);
10233 end Is_Anonymous_Tagged_Base
;
10235 --------------------------------
10236 -- Name_Implies_Lvalue_Prefix --
10237 --------------------------------
10239 function Name_Implies_Lvalue_Prefix
(Nam
: Name_Id
) return Boolean is
10240 pragma Assert
(Is_Attribute_Name
(Nam
));
10242 return Attribute_Name_Implies_Lvalue_Prefix
(Get_Attribute_Id
(Nam
));
10243 end Name_Implies_Lvalue_Prefix
;
10245 -----------------------
10246 -- Resolve_Attribute --
10247 -----------------------
10249 procedure Resolve_Attribute
(N
: Node_Id
; Typ
: Entity_Id
) is
10250 Loc
: constant Source_Ptr
:= Sloc
(N
);
10251 P
: constant Node_Id
:= Prefix
(N
);
10252 Aname
: constant Name_Id
:= Attribute_Name
(N
);
10253 Attr_Id
: constant Attribute_Id
:= Get_Attribute_Id
(Aname
);
10254 Btyp
: constant Entity_Id
:= Base_Type
(Typ
);
10255 Des_Btyp
: Entity_Id
;
10256 Index
: Interp_Index
;
10258 Nom_Subt
: Entity_Id
;
10260 procedure Accessibility_Message
;
10261 -- Error, or warning within an instance, if the static accessibility
10262 -- rules of 3.10.2 are violated.
10264 function Declared_Within_Generic_Unit
10265 (Entity
: Entity_Id
;
10266 Generic_Unit
: Node_Id
) return Boolean;
10267 -- Returns True if Declared_Entity is declared within the declarative
10268 -- region of Generic_Unit; otherwise returns False.
10270 ---------------------------
10271 -- Accessibility_Message --
10272 ---------------------------
10274 procedure Accessibility_Message
is
10275 Indic
: Node_Id
:= Parent
(Parent
(N
));
10278 -- In an instance, this is a runtime check, but one we
10279 -- know will fail, so generate an appropriate warning.
10281 if In_Instance_Body
then
10282 Error_Msg_Warn
:= SPARK_Mode
/= On
;
10284 ("non-local pointer cannot point to local object<<", P
);
10285 Error_Msg_F
("\Program_Error [<<", P
);
10287 Make_Raise_Program_Error
(Loc
,
10288 Reason
=> PE_Accessibility_Check_Failed
));
10289 Set_Etype
(N
, Typ
);
10293 Error_Msg_F
("non-local pointer cannot point to local object", P
);
10295 -- Check for case where we have a missing access definition
10297 if Is_Record_Type
(Current_Scope
)
10299 Nkind_In
(Parent
(N
), N_Discriminant_Association
,
10300 N_Index_Or_Discriminant_Constraint
)
10302 Indic
:= Parent
(Parent
(N
));
10303 while Present
(Indic
)
10304 and then Nkind
(Indic
) /= N_Subtype_Indication
10306 Indic
:= Parent
(Indic
);
10309 if Present
(Indic
) then
10311 ("\use an access definition for" &
10312 " the access discriminant of&",
10313 N
, Entity
(Subtype_Mark
(Indic
)));
10317 end Accessibility_Message
;
10319 ----------------------------------
10320 -- Declared_Within_Generic_Unit --
10321 ----------------------------------
10323 function Declared_Within_Generic_Unit
10324 (Entity
: Entity_Id
;
10325 Generic_Unit
: Node_Id
) return Boolean
10327 Generic_Encloser
: Node_Id
:= Enclosing_Generic_Unit
(Entity
);
10330 while Present
(Generic_Encloser
) loop
10331 if Generic_Encloser
= Generic_Unit
then
10335 -- We have to step to the scope of the generic's entity, because
10336 -- otherwise we'll just get back the same generic.
10338 Generic_Encloser
:=
10339 Enclosing_Generic_Unit
10340 (Scope
(Defining_Entity
(Generic_Encloser
)));
10344 end Declared_Within_Generic_Unit
;
10346 -- Start of processing for Resolve_Attribute
10349 -- If error during analysis, no point in continuing, except for array
10350 -- types, where we get better recovery by using unconstrained indexes
10351 -- than nothing at all (see Check_Array_Type).
10353 if Error_Posted
(N
)
10354 and then Attr_Id
/= Attribute_First
10355 and then Attr_Id
/= Attribute_Last
10356 and then Attr_Id
/= Attribute_Length
10357 and then Attr_Id
/= Attribute_Range
10362 -- If attribute was universal type, reset to actual type
10364 if Etype
(N
) = Universal_Integer
10365 or else Etype
(N
) = Universal_Real
10367 Set_Etype
(N
, Typ
);
10370 -- Remaining processing depends on attribute
10378 -- For access attributes, if the prefix denotes an entity, it is
10379 -- interpreted as a name, never as a call. It may be overloaded,
10380 -- in which case resolution uses the profile of the context type.
10381 -- Otherwise prefix must be resolved.
10383 when Attribute_Access
10384 | Attribute_Unchecked_Access
10385 | Attribute_Unrestricted_Access
10387 -- Note possible modification if we have a variable
10389 if Is_Variable
(P
) then
10391 PN
: constant Node_Id
:= Parent
(N
);
10394 Note
: Boolean := True;
10395 -- Skip this for the case of Unrestricted_Access occuring in
10396 -- the context of a Valid check, since this otherwise leads
10397 -- to a missed warning (the Valid check does not really
10398 -- modify!) If this case, Note will be reset to False.
10400 -- Skip it as well if the type is an Acccess_To_Constant,
10401 -- given that no use of the value can modify the prefix.
10404 if Attr_Id
= Attribute_Unrestricted_Access
10405 and then Nkind
(PN
) = N_Function_Call
10409 if Nkind
(Nm
) = N_Expanded_Name
10410 and then Chars
(Nm
) = Name_Valid
10411 and then Nkind
(Prefix
(Nm
)) = N_Identifier
10412 and then Chars
(Prefix
(Nm
)) = Name_Attr_Long_Float
10417 elsif Is_Access_Constant
(Typ
) then
10422 Note_Possible_Modification
(P
, Sure
=> False);
10427 -- The following comes from a query concerning improper use of
10428 -- universal_access in equality tests involving anonymous access
10429 -- types. Another good reason for 'Ref, but for now disable the
10430 -- test, which breaks several filed tests???
10432 if Ekind
(Typ
) = E_Anonymous_Access_Type
10433 and then Nkind_In
(Parent
(N
), N_Op_Eq
, N_Op_Ne
)
10436 Error_Msg_N
("need unique type to resolve 'Access", N
);
10437 Error_Msg_N
("\qualify attribute with some access type", N
);
10440 -- Case where prefix is an entity name
10442 if Is_Entity_Name
(P
) then
10444 -- Deal with case where prefix itself is overloaded
10446 if Is_Overloaded
(P
) then
10447 Get_First_Interp
(P
, Index
, It
);
10448 while Present
(It
.Nam
) loop
10449 if Type_Conformant
(Designated_Type
(Typ
), It
.Nam
) then
10450 Set_Entity
(P
, It
.Nam
);
10452 -- The prefix is definitely NOT overloaded anymore at
10453 -- this point, so we reset the Is_Overloaded flag to
10454 -- avoid any confusion when reanalyzing the node.
10456 Set_Is_Overloaded
(P
, False);
10457 Set_Is_Overloaded
(N
, False);
10458 Generate_Reference
(Entity
(P
), P
);
10462 Get_Next_Interp
(Index
, It
);
10465 -- If Prefix is a subprogram name, this reference freezes,
10466 -- but not if within spec expression mode. The profile of
10467 -- the subprogram is not frozen at this point.
10469 if not In_Spec_Expression
then
10470 Freeze_Before
(N
, Entity
(P
), Do_Freeze_Profile
=> False);
10473 -- If it is a type, there is nothing to resolve.
10474 -- If it is a subprogram, do not freeze its profile.
10475 -- If it is an object, complete its resolution.
10477 elsif Is_Overloadable
(Entity
(P
)) then
10478 if not In_Spec_Expression
then
10479 Freeze_Before
(N
, Entity
(P
), Do_Freeze_Profile
=> False);
10482 -- Nothing to do if prefix is a type name
10484 elsif Is_Type
(Entity
(P
)) then
10487 -- Otherwise non-overloaded other case, resolve the prefix
10493 -- Some further error checks
10495 Error_Msg_Name_1
:= Aname
;
10497 if not Is_Entity_Name
(P
) then
10500 elsif Is_Overloadable
(Entity
(P
))
10501 and then Is_Abstract_Subprogram
(Entity
(P
))
10503 Error_Msg_F
("prefix of % attribute cannot be abstract", P
);
10504 Set_Etype
(N
, Any_Type
);
10506 elsif Ekind
(Entity
(P
)) = E_Enumeration_Literal
then
10508 ("prefix of % attribute cannot be enumeration literal", P
);
10509 Set_Etype
(N
, Any_Type
);
10511 -- An attempt to take 'Access of a function that renames an
10512 -- enumeration literal. Issue a specialized error message.
10514 elsif Ekind
(Entity
(P
)) = E_Function
10515 and then Present
(Alias
(Entity
(P
)))
10516 and then Ekind
(Alias
(Entity
(P
))) = E_Enumeration_Literal
10519 ("prefix of % attribute cannot be function renaming "
10520 & "an enumeration literal", P
);
10521 Set_Etype
(N
, Any_Type
);
10523 elsif Convention
(Entity
(P
)) = Convention_Intrinsic
then
10524 Error_Msg_F
("prefix of % attribute cannot be intrinsic", P
);
10525 Set_Etype
(N
, Any_Type
);
10528 -- Assignments, return statements, components of aggregates,
10529 -- generic instantiations will require convention checks if
10530 -- the type is an access to subprogram. Given that there will
10531 -- also be accessibility checks on those, this is where the
10532 -- checks can eventually be centralized ???
10534 if Ekind_In
(Btyp
, E_Access_Protected_Subprogram_Type
,
10535 E_Access_Subprogram_Type
,
10536 E_Anonymous_Access_Protected_Subprogram_Type
,
10537 E_Anonymous_Access_Subprogram_Type
)
10539 -- Deal with convention mismatch
10541 if Convention
(Designated_Type
(Btyp
)) /=
10542 Convention
(Entity
(P
))
10544 -- The rule in 6.3.1 (8) deserves a special error
10547 if Convention
(Btyp
) = Convention_Intrinsic
10548 and then Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
10549 and then Is_Entity_Name
(Name
(Parent
(N
)))
10550 and then Inside_A_Generic
10553 Subp
: constant Entity_Id
:=
10554 Entity
(Name
(Parent
(N
)));
10556 if Convention
(Subp
) = Convention_Intrinsic
then
10558 ("?subprogram and its formal access "
10559 & "parameters have convention Intrinsic",
10562 ("actual cannot be access attribute", N
);
10568 ("subprogram & has wrong convention", P
, Entity
(P
));
10569 Error_Msg_Sloc
:= Sloc
(Btyp
);
10570 Error_Msg_FE
("\does not match & declared#", P
, Btyp
);
10573 if not Is_Itype
(Btyp
)
10574 and then not Has_Convention_Pragma
(Btyp
)
10577 ("\probable missing pragma Convention for &",
10582 Check_Subtype_Conformant
10583 (New_Id
=> Entity
(P
),
10584 Old_Id
=> Designated_Type
(Btyp
),
10588 if Attr_Id
= Attribute_Unchecked_Access
then
10589 Error_Msg_Name_1
:= Aname
;
10591 ("attribute% cannot be applied to a subprogram", P
);
10593 elsif Aname
= Name_Unrestricted_Access
then
10594 null; -- Nothing to check
10596 -- Check the static accessibility rule of 3.10.2(32).
10597 -- This rule also applies within the private part of an
10598 -- instantiation. This rule does not apply to anonymous
10599 -- access-to-subprogram types in access parameters.
10601 elsif Attr_Id
= Attribute_Access
10602 and then not In_Instance_Body
10604 (Ekind
(Btyp
) = E_Access_Subprogram_Type
10605 or else Is_Local_Anonymous_Access
(Btyp
))
10606 and then Subprogram_Access_Level
(Entity
(P
)) >
10607 Type_Access_Level
(Btyp
)
10610 ("subprogram must not be deeper than access type", P
);
10612 -- Check the restriction of 3.10.2(32) that disallows the
10613 -- access attribute within a generic body when the ultimate
10614 -- ancestor of the type of the attribute is declared outside
10615 -- of the generic unit and the subprogram is declared within
10616 -- that generic unit. This includes any such attribute that
10617 -- occurs within the body of a generic unit that is a child
10618 -- of the generic unit where the subprogram is declared.
10620 -- The rule also prohibits applying the attribute when the
10621 -- access type is a generic formal access type (since the
10622 -- level of the actual type is not known). This restriction
10623 -- does not apply when the attribute type is an anonymous
10624 -- access-to-subprogram type. Note that this check was
10625 -- revised by AI-229, because the original Ada 95 rule
10626 -- was too lax. The original rule only applied when the
10627 -- subprogram was declared within the body of the generic,
10628 -- which allowed the possibility of dangling references).
10629 -- The rule was also too strict in some cases, in that it
10630 -- didn't permit the access to be declared in the generic
10631 -- spec, whereas the revised rule does (as long as it's not
10634 -- There are a couple of subtleties of the test for applying
10635 -- the check that are worth noting. First, we only apply it
10636 -- when the levels of the subprogram and access type are the
10637 -- same (the case where the subprogram is statically deeper
10638 -- was applied above, and the case where the type is deeper
10639 -- is always safe). Second, we want the check to apply
10640 -- within nested generic bodies and generic child unit
10641 -- bodies, but not to apply to an attribute that appears in
10642 -- the generic unit's specification. This is done by testing
10643 -- that the attribute's innermost enclosing generic body is
10644 -- not the same as the innermost generic body enclosing the
10645 -- generic unit where the subprogram is declared (we don't
10646 -- want the check to apply when the access attribute is in
10647 -- the spec and there's some other generic body enclosing
10648 -- generic). Finally, there's no point applying the check
10649 -- when within an instance, because any violations will have
10650 -- been caught by the compilation of the generic unit.
10652 -- We relax this check in Relaxed_RM_Semantics mode for
10653 -- compatibility with legacy code for use by Ada source
10654 -- code analyzers (e.g. CodePeer).
10656 elsif Attr_Id
= Attribute_Access
10657 and then not Relaxed_RM_Semantics
10658 and then not In_Instance
10659 and then Present
(Enclosing_Generic_Unit
(Entity
(P
)))
10660 and then Present
(Enclosing_Generic_Body
(N
))
10661 and then Enclosing_Generic_Body
(N
) /=
10662 Enclosing_Generic_Body
10663 (Enclosing_Generic_Unit
(Entity
(P
)))
10664 and then Subprogram_Access_Level
(Entity
(P
)) =
10665 Type_Access_Level
(Btyp
)
10666 and then Ekind
(Btyp
) /=
10667 E_Anonymous_Access_Subprogram_Type
10668 and then Ekind
(Btyp
) /=
10669 E_Anonymous_Access_Protected_Subprogram_Type
10671 -- The attribute type's ultimate ancestor must be
10672 -- declared within the same generic unit as the
10673 -- subprogram is declared (including within another
10674 -- nested generic unit). The error message is
10675 -- specialized to say "ancestor" for the case where the
10676 -- access type is not its own ancestor, since saying
10677 -- simply "access type" would be very confusing.
10679 if not Declared_Within_Generic_Unit
10681 Enclosing_Generic_Unit
(Entity
(P
)))
10684 ("''Access attribute not allowed in generic body",
10687 if Root_Type
(Btyp
) = Btyp
then
10690 "access type & is declared outside " &
10691 "generic unit (RM 3.10.2(32))", N
, Btyp
);
10694 ("\because ancestor of " &
10695 "access type & is declared outside " &
10696 "generic unit (RM 3.10.2(32))", N
, Btyp
);
10700 ("\move ''Access to private part, or " &
10701 "(Ada 2005) use anonymous access type instead of &",
10704 -- If the ultimate ancestor of the attribute's type is
10705 -- a formal type, then the attribute is illegal because
10706 -- the actual type might be declared at a higher level.
10707 -- The error message is specialized to say "ancestor"
10708 -- for the case where the access type is not its own
10709 -- ancestor, since saying simply "access type" would be
10712 elsif Is_Generic_Type
(Root_Type
(Btyp
)) then
10713 if Root_Type
(Btyp
) = Btyp
then
10715 ("access type must not be a generic formal type",
10719 ("ancestor access type must not be a generic " &
10726 -- If this is a renaming, an inherited operation, or a
10727 -- subprogram instance, use the original entity. This may make
10728 -- the node type-inconsistent, so this transformation can only
10729 -- be done if the node will not be reanalyzed. In particular,
10730 -- if it is within a default expression, the transformation
10731 -- must be delayed until the default subprogram is created for
10732 -- it, when the enclosing subprogram is frozen.
10734 if Is_Entity_Name
(P
)
10735 and then Is_Overloadable
(Entity
(P
))
10736 and then Present
(Alias
(Entity
(P
)))
10737 and then Expander_Active
10740 New_Occurrence_Of
(Alias
(Entity
(P
)), Sloc
(P
)));
10743 elsif Nkind
(P
) = N_Selected_Component
10744 and then Is_Overloadable
(Entity
(Selector_Name
(P
)))
10746 -- Protected operation. If operation is overloaded, must
10747 -- disambiguate. Prefix that denotes protected object itself
10748 -- is resolved with its own type.
10750 if Attr_Id
= Attribute_Unchecked_Access
then
10751 Error_Msg_Name_1
:= Aname
;
10753 ("attribute% cannot be applied to protected operation", P
);
10756 Resolve
(Prefix
(P
));
10757 Generate_Reference
(Entity
(Selector_Name
(P
)), P
);
10759 -- Implement check implied by 3.10.2 (18.1/2) : F.all'access is
10760 -- statically illegal if F is an anonymous access to subprogram.
10762 elsif Nkind
(P
) = N_Explicit_Dereference
10763 and then Is_Entity_Name
(Prefix
(P
))
10764 and then Ekind
(Etype
(Entity
(Prefix
(P
)))) =
10765 E_Anonymous_Access_Subprogram_Type
10767 Error_Msg_N
("anonymous access to subprogram "
10768 & "has deeper accessibility than any master", P
);
10770 elsif Is_Overloaded
(P
) then
10772 -- Use the designated type of the context to disambiguate
10773 -- Note that this was not strictly conformant to Ada 95,
10774 -- but was the implementation adopted by most Ada 95 compilers.
10775 -- The use of the context type to resolve an Access attribute
10776 -- reference is now mandated in AI-235 for Ada 2005.
10779 Index
: Interp_Index
;
10783 Get_First_Interp
(P
, Index
, It
);
10784 while Present
(It
.Typ
) loop
10785 if Covers
(Designated_Type
(Typ
), It
.Typ
) then
10786 Resolve
(P
, It
.Typ
);
10790 Get_Next_Interp
(Index
, It
);
10797 -- X'Access is illegal if X denotes a constant and the access type
10798 -- is access-to-variable. Same for 'Unchecked_Access. The rule
10799 -- does not apply to 'Unrestricted_Access. If the reference is a
10800 -- default-initialized aggregate component for a self-referential
10801 -- type the reference is legal.
10803 if not (Ekind
(Btyp
) = E_Access_Subprogram_Type
10804 or else Ekind
(Btyp
) = E_Anonymous_Access_Subprogram_Type
10805 or else (Is_Record_Type
(Btyp
)
10807 Present
(Corresponding_Remote_Type
(Btyp
)))
10808 or else Ekind
(Btyp
) = E_Access_Protected_Subprogram_Type
10809 or else Ekind
(Btyp
)
10810 = E_Anonymous_Access_Protected_Subprogram_Type
10811 or else Is_Access_Constant
(Btyp
)
10812 or else Is_Variable
(P
)
10813 or else Attr_Id
= Attribute_Unrestricted_Access
)
10815 if Is_Entity_Name
(P
)
10816 and then Is_Type
(Entity
(P
))
10818 -- Legality of a self-reference through an access
10819 -- attribute has been verified in Analyze_Access_Attribute.
10823 elsif Comes_From_Source
(N
) then
10824 Error_Msg_F
("access-to-variable designates constant", P
);
10828 Des_Btyp
:= Designated_Type
(Btyp
);
10830 if Ada_Version
>= Ada_2005
10831 and then Is_Incomplete_Type
(Des_Btyp
)
10833 -- Ada 2005 (AI-412): If the (sub)type is a limited view of an
10834 -- imported entity, and the non-limited view is visible, make
10835 -- use of it. If it is an incomplete subtype, use the base type
10838 if From_Limited_With
(Des_Btyp
)
10839 and then Present
(Non_Limited_View
(Des_Btyp
))
10841 Des_Btyp
:= Non_Limited_View
(Des_Btyp
);
10843 elsif Ekind
(Des_Btyp
) = E_Incomplete_Subtype
then
10844 Des_Btyp
:= Etype
(Des_Btyp
);
10848 if (Attr_Id
= Attribute_Access
10850 Attr_Id
= Attribute_Unchecked_Access
)
10851 and then (Ekind
(Btyp
) = E_General_Access_Type
10852 or else Ekind
(Btyp
) = E_Anonymous_Access_Type
)
10854 -- Ada 2005 (AI-230): Check the accessibility of anonymous
10855 -- access types for stand-alone objects, record and array
10856 -- components, and return objects. For a component definition
10857 -- the level is the same of the enclosing composite type.
10859 if Ada_Version
>= Ada_2005
10860 and then (Is_Local_Anonymous_Access
(Btyp
)
10862 -- Handle cases where Btyp is the anonymous access
10863 -- type of an Ada 2012 stand-alone object.
10865 or else Nkind
(Associated_Node_For_Itype
(Btyp
)) =
10866 N_Object_Declaration
)
10868 Object_Access_Level
(P
) > Deepest_Type_Access_Level
(Btyp
)
10869 and then Attr_Id
= Attribute_Access
10871 -- In an instance, this is a runtime check, but one we know
10872 -- will fail, so generate an appropriate warning. As usual,
10873 -- this kind of warning is an error in SPARK mode.
10875 if In_Instance_Body
then
10876 Error_Msg_Warn
:= SPARK_Mode
/= On
;
10878 ("non-local pointer cannot point to local object<<", P
);
10879 Error_Msg_F
("\Program_Error [<<", P
);
10882 Make_Raise_Program_Error
(Loc
,
10883 Reason
=> PE_Accessibility_Check_Failed
));
10884 Set_Etype
(N
, Typ
);
10888 ("non-local pointer cannot point to local object", P
);
10892 if Is_Dependent_Component_Of_Mutable_Object
(P
) then
10894 ("illegal attribute for discriminant-dependent component",
10898 -- Check static matching rule of 3.10.2(27). Nominal subtype
10899 -- of the prefix must statically match the designated type.
10901 Nom_Subt
:= Etype
(P
);
10903 if Is_Constr_Subt_For_U_Nominal
(Nom_Subt
) then
10904 Nom_Subt
:= Base_Type
(Nom_Subt
);
10907 if Is_Tagged_Type
(Designated_Type
(Typ
)) then
10909 -- If the attribute is in the context of an access
10910 -- parameter, then the prefix is allowed to be of
10911 -- the class-wide type (by AI-127).
10913 if Ekind
(Typ
) = E_Anonymous_Access_Type
then
10914 if not Covers
(Designated_Type
(Typ
), Nom_Subt
)
10915 and then not Covers
(Nom_Subt
, Designated_Type
(Typ
))
10921 Desig
:= Designated_Type
(Typ
);
10923 if Is_Class_Wide_Type
(Desig
) then
10924 Desig
:= Etype
(Desig
);
10927 if Is_Anonymous_Tagged_Base
(Nom_Subt
, Desig
) then
10932 ("type of prefix: & not compatible",
10935 ("\with &, the expected designated type",
10936 P
, Designated_Type
(Typ
));
10941 elsif not Covers
(Designated_Type
(Typ
), Nom_Subt
)
10943 (not Is_Class_Wide_Type
(Designated_Type
(Typ
))
10944 and then Is_Class_Wide_Type
(Nom_Subt
))
10947 ("type of prefix: & is not covered", P
, Nom_Subt
);
10949 ("\by &, the expected designated type" &
10950 " (RM 3.10.2 (27))", P
, Designated_Type
(Typ
));
10953 if Is_Class_Wide_Type
(Designated_Type
(Typ
))
10954 and then Has_Discriminants
(Etype
(Designated_Type
(Typ
)))
10955 and then Is_Constrained
(Etype
(Designated_Type
(Typ
)))
10956 and then Designated_Type
(Typ
) /= Nom_Subt
10958 Apply_Discriminant_Check
10959 (N
, Etype
(Designated_Type
(Typ
)));
10962 -- Ada 2005 (AI-363): Require static matching when designated
10963 -- type has discriminants and a constrained partial view, since
10964 -- in general objects of such types are mutable, so we can't
10965 -- allow the access value to designate a constrained object
10966 -- (because access values must be assumed to designate mutable
10967 -- objects when designated type does not impose a constraint).
10969 elsif Subtypes_Statically_Match
(Des_Btyp
, Nom_Subt
) then
10972 elsif Has_Discriminants
(Designated_Type
(Typ
))
10973 and then not Is_Constrained
(Des_Btyp
)
10975 (Ada_Version
< Ada_2005
10977 not Object_Type_Has_Constrained_Partial_View
10978 (Typ
=> Designated_Type
(Base_Type
(Typ
)),
10979 Scop
=> Current_Scope
))
10985 ("object subtype must statically match "
10986 & "designated subtype", P
);
10988 if Is_Entity_Name
(P
)
10989 and then Is_Array_Type
(Designated_Type
(Typ
))
10992 D
: constant Node_Id
:= Declaration_Node
(Entity
(P
));
10995 ("aliased object has explicit bounds??", D
);
10997 ("\declare without bounds (and with explicit "
10998 & "initialization)??", D
);
11000 ("\for use with unconstrained access??", D
);
11005 -- Check the static accessibility rule of 3.10.2(28). Note that
11006 -- this check is not performed for the case of an anonymous
11007 -- access type, since the access attribute is always legal
11008 -- in such a context.
11010 if Attr_Id
/= Attribute_Unchecked_Access
11011 and then Ekind
(Btyp
) = E_General_Access_Type
11013 Object_Access_Level
(P
) > Deepest_Type_Access_Level
(Btyp
)
11015 Accessibility_Message
;
11020 if Ekind_In
(Btyp
, E_Access_Protected_Subprogram_Type
,
11021 E_Anonymous_Access_Protected_Subprogram_Type
)
11023 if Is_Entity_Name
(P
)
11024 and then not Is_Protected_Type
(Scope
(Entity
(P
)))
11026 Error_Msg_F
("context requires a protected subprogram", P
);
11028 -- Check accessibility of protected object against that of the
11029 -- access type, but only on user code, because the expander
11030 -- creates access references for handlers. If the context is an
11031 -- anonymous_access_to_protected, there are no accessibility
11032 -- checks either. Omit check entirely for Unrestricted_Access.
11034 elsif Object_Access_Level
(P
) > Deepest_Type_Access_Level
(Btyp
)
11035 and then Comes_From_Source
(N
)
11036 and then Ekind
(Btyp
) = E_Access_Protected_Subprogram_Type
11037 and then Attr_Id
/= Attribute_Unrestricted_Access
11039 Accessibility_Message
;
11042 -- AI05-0225: If the context is not an access to protected
11043 -- function, the prefix must be a variable, given that it may
11044 -- be used subsequently in a protected call.
11046 elsif Nkind
(P
) = N_Selected_Component
11047 and then not Is_Variable
(Prefix
(P
))
11048 and then Ekind
(Entity
(Selector_Name
(P
))) /= E_Function
11051 ("target object of access to protected procedure "
11052 & "must be variable", N
);
11054 elsif Is_Entity_Name
(P
) then
11055 Check_Internal_Protected_Use
(N
, Entity
(P
));
11058 elsif Ekind_In
(Btyp
, E_Access_Subprogram_Type
,
11059 E_Anonymous_Access_Subprogram_Type
)
11060 and then Ekind
(Etype
(N
)) = E_Access_Protected_Subprogram_Type
11062 Error_Msg_F
("context requires a non-protected subprogram", P
);
11065 -- The context cannot be a pool-specific type, but this is a
11066 -- legality rule, not a resolution rule, so it must be checked
11067 -- separately, after possibly disambiguation (see AI-245).
11069 if Ekind
(Btyp
) = E_Access_Type
11070 and then Attr_Id
/= Attribute_Unrestricted_Access
11072 Wrong_Type
(N
, Typ
);
11075 -- The context may be a constrained access type (however ill-
11076 -- advised such subtypes might be) so in order to generate a
11077 -- constraint check when needed set the type of the attribute
11078 -- reference to the base type of the context.
11080 Set_Etype
(N
, Btyp
);
11082 -- Check for incorrect atomic/volatile reference (RM C.6(12))
11084 if Attr_Id
/= Attribute_Unrestricted_Access
then
11085 if Is_Atomic_Object
(P
)
11086 and then not Is_Atomic
(Designated_Type
(Typ
))
11089 ("access to atomic object cannot yield access-to-" &
11090 "non-atomic type", P
);
11092 elsif Is_Volatile_Object
(P
)
11093 and then not Is_Volatile
(Designated_Type
(Typ
))
11096 ("access to volatile object cannot yield access-to-" &
11097 "non-volatile type", P
);
11101 -- Check for aliased view. We allow a nonaliased prefix when in
11102 -- an instance because the prefix may have been a tagged formal
11103 -- object, which is defined to be aliased even when the actual
11104 -- might not be (other instance cases will have been caught in
11105 -- the generic). Similarly, within an inlined body we know that
11106 -- the attribute is legal in the original subprogram, therefore
11107 -- legal in the expansion.
11109 if not (Is_Entity_Name
(P
)
11110 and then Is_Overloadable
(Entity
(P
)))
11111 and then not (Nkind
(P
) = N_Selected_Component
11113 Is_Overloadable
(Entity
(Selector_Name
(P
))))
11114 and then not Is_Aliased_View
(Original_Node
(P
))
11115 and then not In_Instance
11116 and then not In_Inlined_Body
11117 and then Comes_From_Source
(N
)
11119 -- Here we have a non-aliased view. This is illegal unless we
11120 -- have the case of Unrestricted_Access, where for now we allow
11121 -- this (we will reject later if expected type is access to an
11122 -- unconstrained array with a thin pointer).
11124 -- No need for an error message on a generated access reference
11125 -- for the controlling argument in a dispatching call: error
11126 -- will be reported when resolving the call.
11128 if Attr_Id
/= Attribute_Unrestricted_Access
then
11129 Error_Msg_N
("prefix of % attribute must be aliased", P
);
11131 -- Check for unrestricted access where expected type is a thin
11132 -- pointer to an unconstrained array.
11134 elsif Has_Size_Clause
(Typ
)
11135 and then RM_Size
(Typ
) = System_Address_Size
11138 DT
: constant Entity_Id
:= Designated_Type
(Typ
);
11140 if Is_Array_Type
(DT
)
11141 and then not Is_Constrained
(DT
)
11144 ("illegal use of Unrestricted_Access attribute", P
);
11146 ("\attempt to generate thin pointer to unaliased "
11153 -- Mark that address of entity is taken in case of
11154 -- 'Unrestricted_Access or in case of a subprogram.
11156 if Is_Entity_Name
(P
)
11157 and then (Attr_Id
= Attribute_Unrestricted_Access
11158 or else Is_Subprogram
(Entity
(P
)))
11160 Set_Address_Taken
(Entity
(P
));
11163 -- Deal with possible elaboration check
11165 if Is_Entity_Name
(P
) and then Is_Subprogram
(Entity
(P
)) then
11167 Subp_Id
: constant Entity_Id
:= Entity
(P
);
11168 Scop
: constant Entity_Id
:= Scope
(Subp_Id
);
11169 Subp_Decl
: constant Node_Id
:=
11170 Unit_Declaration_Node
(Subp_Id
);
11171 Flag_Id
: Entity_Id
;
11172 Subp_Body
: Node_Id
;
11174 -- If the access has been taken and the body of the subprogram
11175 -- has not been see yet, indirect calls must be protected with
11176 -- elaboration checks. We have the proper elaboration machinery
11177 -- for subprograms declared in packages, but within a block or
11178 -- a subprogram the body will appear in the same declarative
11179 -- part, and we must insert a check in the eventual body itself
11180 -- using the elaboration flag that we generate now. The check
11181 -- is then inserted when the body is expanded. This processing
11182 -- is not needed for a stand alone expression function because
11183 -- the internally generated spec and body are always inserted
11184 -- as a pair in the same declarative list.
11188 and then Comes_From_Source
(Subp_Id
)
11189 and then Comes_From_Source
(N
)
11190 and then In_Open_Scopes
(Scop
)
11191 and then Ekind_In
(Scop
, E_Block
, E_Procedure
, E_Function
)
11192 and then not Has_Completion
(Subp_Id
)
11193 and then No
(Elaboration_Entity
(Subp_Id
))
11194 and then Nkind
(Subp_Decl
) = N_Subprogram_Declaration
11195 and then Nkind
(Original_Node
(Subp_Decl
)) /=
11196 N_Expression_Function
11198 -- Create elaboration variable for it
11200 Flag_Id
:= Make_Temporary
(Loc
, 'E');
11201 Set_Elaboration_Entity
(Subp_Id
, Flag_Id
);
11202 Set_Is_Frozen
(Flag_Id
);
11204 -- Insert declaration for flag after subprogram
11205 -- declaration. Note that attribute reference may
11206 -- appear within a nested scope.
11208 Insert_After_And_Analyze
(Subp_Decl
,
11209 Make_Object_Declaration
(Loc
,
11210 Defining_Identifier
=> Flag_Id
,
11211 Object_Definition
=>
11212 New_Occurrence_Of
(Standard_Short_Integer
, Loc
),
11214 Make_Integer_Literal
(Loc
, Uint_0
)));
11217 -- Taking the 'Access of an expression function freezes its
11218 -- expression (RM 13.14 10.3/3). This does not apply to an
11219 -- expression function that acts as a completion because the
11220 -- generated body is immediately analyzed and the expression
11221 -- is automatically frozen.
11223 if Is_Expression_Function
(Subp_Id
)
11224 and then Present
(Corresponding_Body
(Subp_Decl
))
11227 Unit_Declaration_Node
(Corresponding_Body
(Subp_Decl
));
11229 -- The body has already been analyzed when the expression
11230 -- function acts as a completion.
11232 if Analyzed
(Subp_Body
) then
11235 -- Attribute 'Access may appear within the generated body
11236 -- of the expression function subject to the attribute:
11238 -- function F is (... F'Access ...);
11240 -- If the expression function is on the scope stack, then
11241 -- the body is currently being analyzed. Do not reanalyze
11242 -- it because this will lead to infinite recursion.
11244 elsif In_Open_Scopes
(Subp_Id
) then
11247 -- If reference to the expression function appears in an
11248 -- inner scope, for example as an actual in an instance,
11249 -- this is not a freeze point either.
11251 elsif Scope
(Subp_Id
) /= Current_Scope
then
11254 -- Analyze the body of the expression function to freeze
11255 -- the expression. This takes care of the case where the
11256 -- 'Access is part of dispatch table initialization and
11257 -- the generated body of the expression function has not
11258 -- been analyzed yet.
11261 Analyze
(Subp_Body
);
11271 -- Deal with resolving the type for Address attribute, overloading
11272 -- is not permitted here, since there is no context to resolve it.
11274 when Attribute_Address
11275 | Attribute_Code_Address
11277 -- To be safe, assume that if the address of a variable is taken,
11278 -- it may be modified via this address, so note modification.
11280 if Is_Variable
(P
) then
11281 Note_Possible_Modification
(P
, Sure
=> False);
11284 if Nkind
(P
) in N_Subexpr
11285 and then Is_Overloaded
(P
)
11287 Get_First_Interp
(P
, Index
, It
);
11288 Get_Next_Interp
(Index
, It
);
11290 if Present
(It
.Nam
) then
11291 Error_Msg_Name_1
:= Aname
;
11293 ("prefix of % attribute cannot be overloaded", P
);
11297 if not Is_Entity_Name
(P
)
11298 or else not Is_Overloadable
(Entity
(P
))
11300 if not Is_Task_Type
(Etype
(P
))
11301 or else Nkind
(P
) = N_Explicit_Dereference
11307 -- If this is the name of a derived subprogram, or that of a
11308 -- generic actual, the address is that of the original entity.
11310 if Is_Entity_Name
(P
)
11311 and then Is_Overloadable
(Entity
(P
))
11312 and then Present
(Alias
(Entity
(P
)))
11315 New_Occurrence_Of
(Alias
(Entity
(P
)), Sloc
(P
)));
11318 if Is_Entity_Name
(P
) then
11319 Set_Address_Taken
(Entity
(P
));
11322 if Nkind
(P
) = N_Slice
then
11324 -- Arr (X .. Y)'address is identical to Arr (X)'address,
11325 -- even if the array is packed and the slice itself is not
11326 -- addressable. Transform the prefix into an indexed component.
11328 -- Note that the transformation is safe only if we know that
11329 -- the slice is non-null. That is because a null slice can have
11330 -- an out of bounds index value.
11332 -- Right now, gigi blows up if given 'Address on a slice as a
11333 -- result of some incorrect freeze nodes generated by the front
11334 -- end, and this covers up that bug in one case, but the bug is
11335 -- likely still there in the cases not handled by this code ???
11337 -- It's not clear what 'Address *should* return for a null
11338 -- slice with out of bounds indexes, this might be worth an ARG
11341 -- One approach would be to do a length check unconditionally,
11342 -- and then do the transformation below unconditionally, but
11343 -- analyze with checks off, avoiding the problem of the out of
11344 -- bounds index. This approach would interpret the address of
11345 -- an out of bounds null slice as being the address where the
11346 -- array element would be if there was one, which is probably
11347 -- as reasonable an interpretation as any ???
11350 Loc
: constant Source_Ptr
:= Sloc
(P
);
11351 D
: constant Node_Id
:= Discrete_Range
(P
);
11355 if Is_Entity_Name
(D
)
11358 (Type_Low_Bound
(Entity
(D
)),
11359 Type_High_Bound
(Entity
(D
)))
11362 Make_Attribute_Reference
(Loc
,
11363 Prefix
=> (New_Occurrence_Of
(Entity
(D
), Loc
)),
11364 Attribute_Name
=> Name_First
);
11366 elsif Nkind
(D
) = N_Range
11367 and then Not_Null_Range
(Low_Bound
(D
), High_Bound
(D
))
11369 Lo
:= Low_Bound
(D
);
11375 if Present
(Lo
) then
11377 Make_Indexed_Component
(Loc
,
11378 Prefix
=> Relocate_Node
(Prefix
(P
)),
11379 Expressions
=> New_List
(Lo
)));
11381 Analyze_And_Resolve
(P
);
11390 -- Prefix of Body_Version attribute can be a subprogram name which
11391 -- must not be resolved, since this is not a call.
11393 when Attribute_Body_Version
=>
11400 -- Prefix of Caller attribute is an entry name which must not
11401 -- be resolved, since this is definitely not an entry call.
11403 when Attribute_Caller
=>
11410 -- Shares processing with Address attribute
11416 -- If the prefix of the Count attribute is an entry name it must not
11417 -- be resolved, since this is definitely not an entry call. However,
11418 -- if it is an element of an entry family, the index itself may
11419 -- have to be resolved because it can be a general expression.
11421 when Attribute_Count
=>
11422 if Nkind
(P
) = N_Indexed_Component
11423 and then Is_Entity_Name
(Prefix
(P
))
11426 Indx
: constant Node_Id
:= First
(Expressions
(P
));
11427 Fam
: constant Entity_Id
:= Entity
(Prefix
(P
));
11429 Resolve
(Indx
, Entry_Index_Type
(Fam
));
11430 Apply_Range_Check
(Indx
, Entry_Index_Type
(Fam
));
11438 -- Prefix of the Elaborated attribute is a subprogram name which
11439 -- must not be resolved, since this is definitely not a call. Note
11440 -- that it is a library unit, so it cannot be overloaded here.
11442 when Attribute_Elaborated
=>
11449 -- Prefix of Enabled attribute is a check name, which must be treated
11450 -- specially and not touched by Resolve.
11452 when Attribute_Enabled
=>
11459 -- Do not resolve the prefix of Loop_Entry, instead wait until the
11460 -- attribute has been expanded (see Expand_Loop_Entry_Attributes).
11461 -- The delay ensures that any generated checks or temporaries are
11462 -- inserted before the relocated prefix.
11464 when Attribute_Loop_Entry
=>
11467 --------------------
11468 -- Mechanism_Code --
11469 --------------------
11471 -- Prefix of the Mechanism_Code attribute is a function name
11472 -- which must not be resolved. Should we check for overloaded ???
11474 when Attribute_Mechanism_Code
=>
11481 -- Most processing is done in sem_dist, after determining the
11482 -- context type. Node is rewritten as a conversion to a runtime call.
11484 when Attribute_Partition_ID
=>
11485 Process_Partition_Id
(N
);
11492 when Attribute_Pool_Address
=>
11499 -- We replace the Range attribute node with a range expression whose
11500 -- bounds are the 'First and 'Last attributes applied to the same
11501 -- prefix. The reason that we do this transformation here instead of
11502 -- in the expander is that it simplifies other parts of the semantic
11503 -- analysis which assume that the Range has been replaced; thus it
11504 -- must be done even when in semantic-only mode (note that the RM
11505 -- specifically mentions this equivalence, we take care that the
11506 -- prefix is only evaluated once).
11508 when Attribute_Range
=> Range_Attribute
: declare
11514 if not Is_Entity_Name
(P
) or else not Is_Type
(Entity
(P
)) then
11518 Dims
:= Expressions
(N
);
11521 Make_Attribute_Reference
(Loc
,
11522 Prefix
=> Duplicate_Subexpr
(P
, Name_Req
=> True),
11523 Attribute_Name
=> Name_Last
,
11524 Expressions
=> Dims
);
11527 Make_Attribute_Reference
(Loc
,
11529 Attribute_Name
=> Name_First
,
11530 Expressions
=> (Dims
));
11532 -- Do not share the dimension indicator, if present. Even though
11533 -- it is a static constant, its source location may be modified
11534 -- when printing expanded code and node sharing will lead to chaos
11537 if Present
(Dims
) then
11538 Set_Expressions
(LB
, New_List
(New_Copy_Tree
(First
(Dims
))));
11541 -- If the original was marked as Must_Not_Freeze (see code in
11542 -- Sem_Ch3.Make_Index), then make sure the rewriting does not
11545 if Must_Not_Freeze
(N
) then
11546 Set_Must_Not_Freeze
(HB
);
11547 Set_Must_Not_Freeze
(LB
);
11548 Set_Must_Not_Freeze
(Prefix
(HB
));
11549 Set_Must_Not_Freeze
(Prefix
(LB
));
11552 if Raises_Constraint_Error
(Prefix
(N
)) then
11554 -- Preserve Sloc of prefix in the new bounds, so that the
11555 -- posted warning can be removed if we are within unreachable
11558 Set_Sloc
(LB
, Sloc
(Prefix
(N
)));
11559 Set_Sloc
(HB
, Sloc
(Prefix
(N
)));
11562 Rewrite
(N
, Make_Range
(Loc
, LB
, HB
));
11563 Analyze_And_Resolve
(N
, Typ
);
11565 -- Ensure that the expanded range does not have side effects
11567 Force_Evaluation
(LB
);
11568 Force_Evaluation
(HB
);
11570 -- Normally after resolving attribute nodes, Eval_Attribute
11571 -- is called to do any possible static evaluation of the node.
11572 -- However, here since the Range attribute has just been
11573 -- transformed into a range expression it is no longer an
11574 -- attribute node and therefore the call needs to be avoided
11575 -- and is accomplished by simply returning from the procedure.
11578 end Range_Attribute
;
11584 -- We will only come here during the prescan of a spec expression
11585 -- containing a Result attribute. In that case the proper Etype has
11586 -- already been set, and nothing more needs to be done here.
11588 when Attribute_Result
=>
11591 ----------------------
11592 -- Unchecked_Access --
11593 ----------------------
11595 -- Processing is shared with Access
11597 -------------------------
11598 -- Unrestricted_Access --
11599 -------------------------
11601 -- Processing is shared with Access
11607 -- Resolve aggregate components in component associations
11609 when Attribute_Update
=> Update
: declare
11610 Aggr
: constant Node_Id
:= First
(Expressions
(N
));
11611 Typ
: constant Entity_Id
:= Etype
(Prefix
(N
));
11617 -- Set the Etype of the aggregate to that of the prefix, even
11618 -- though the aggregate may not be a proper representation of a
11619 -- value of the type (missing or duplicated associations, etc.)
11620 -- Complete resolution of the prefix. Note that in Ada 2012 it
11621 -- can be a qualified expression that is e.g. an aggregate.
11623 Set_Etype
(Aggr
, Typ
);
11624 Resolve
(Prefix
(N
), Typ
);
11626 -- For an array type, resolve expressions with the component type
11627 -- of the array, and apply constraint checks when needed.
11629 if Is_Array_Type
(Typ
) then
11630 Assoc
:= First
(Component_Associations
(Aggr
));
11631 while Present
(Assoc
) loop
11632 Expr
:= Expression
(Assoc
);
11633 Resolve
(Expr
, Component_Type
(Typ
));
11635 -- For scalar array components set Do_Range_Check when
11636 -- needed. Constraint checking on non-scalar components
11637 -- is done in Aggregate_Constraint_Checks, but only if
11638 -- full analysis is enabled. These flags are not set in
11639 -- the front-end in GnatProve mode.
11641 if Is_Scalar_Type
(Component_Type
(Typ
))
11642 and then not Is_OK_Static_Expression
(Expr
)
11643 and then not Range_Checks_Suppressed
(Component_Type
(Typ
))
11645 if Is_Entity_Name
(Expr
)
11646 and then Etype
(Expr
) = Component_Type
(Typ
)
11651 Set_Do_Range_Check
(Expr
);
11655 -- The choices in the association are static constants,
11656 -- or static aggregates each of whose components belongs
11657 -- to the proper index type. However, they must also
11658 -- belong to the index subtype (s) of the prefix, which
11659 -- may be a subtype (e.g. given by a slice).
11661 -- Choices may also be identifiers with no staticness
11662 -- requirements, in which case they must resolve to the
11671 C
:= First
(Choices
(Assoc
));
11672 while Present
(C
) loop
11673 Indx
:= First_Index
(Etype
(Prefix
(N
)));
11675 if Nkind
(C
) /= N_Aggregate
then
11676 Analyze_And_Resolve
(C
, Etype
(Indx
));
11677 Apply_Constraint_Check
(C
, Etype
(Indx
));
11678 Check_Non_Static_Context
(C
);
11681 C_E
:= First
(Expressions
(C
));
11682 while Present
(C_E
) loop
11683 Analyze_And_Resolve
(C_E
, Etype
(Indx
));
11684 Apply_Constraint_Check
(C_E
, Etype
(Indx
));
11685 Check_Non_Static_Context
(C_E
);
11699 -- For a record type, use type of each component, which is
11700 -- recorded during analysis.
11703 Assoc
:= First
(Component_Associations
(Aggr
));
11704 while Present
(Assoc
) loop
11705 Comp
:= First
(Choices
(Assoc
));
11706 Expr
:= Expression
(Assoc
);
11708 if Nkind
(Comp
) /= N_Others_Choice
11709 and then not Error_Posted
(Comp
)
11711 Resolve
(Expr
, Etype
(Entity
(Comp
)));
11713 if Is_Scalar_Type
(Etype
(Entity
(Comp
)))
11714 and then not Is_OK_Static_Expression
(Expr
)
11715 and then not Range_Checks_Suppressed
11716 (Etype
(Entity
(Comp
)))
11718 Set_Do_Range_Check
(Expr
);
11731 -- Apply range check. Note that we did not do this during the
11732 -- analysis phase, since we wanted Eval_Attribute to have a
11733 -- chance at finding an illegal out of range value.
11735 when Attribute_Val
=>
11737 -- Note that we do our own Eval_Attribute call here rather than
11738 -- use the common one, because we need to do processing after
11739 -- the call, as per above comment.
11741 Eval_Attribute
(N
);
11743 -- Eval_Attribute may replace the node with a raise CE, or
11744 -- fold it to a constant. Obviously we only apply a scalar
11745 -- range check if this did not happen.
11747 if Nkind
(N
) = N_Attribute_Reference
11748 and then Attribute_Name
(N
) = Name_Val
11750 Apply_Scalar_Range_Check
(First
(Expressions
(N
)), Btyp
);
11759 -- Prefix of Version attribute can be a subprogram name which
11760 -- must not be resolved, since this is not a call.
11762 when Attribute_Version
=>
11765 ----------------------
11766 -- Other Attributes --
11767 ----------------------
11769 -- For other attributes, resolve prefix unless it is a type. If
11770 -- the attribute reference itself is a type name ('Base and 'Class)
11771 -- then this is only legal within a task or protected record.
11774 if not Is_Entity_Name
(P
) or else not Is_Type
(Entity
(P
)) then
11778 -- If the attribute reference itself is a type name ('Base,
11779 -- 'Class) then this is only legal within a task or protected
11780 -- record. What is this all about ???
11782 if Is_Entity_Name
(N
) and then Is_Type
(Entity
(N
)) then
11783 if Is_Concurrent_Type
(Entity
(N
))
11784 and then In_Open_Scopes
(Entity
(P
))
11789 ("invalid use of subtype name in expression or call", N
);
11793 -- For attributes whose argument may be a string, complete
11794 -- resolution of argument now. This avoids premature expansion
11795 -- (and the creation of transient scopes) before the attribute
11796 -- reference is resolved.
11799 when Attribute_Value
=>
11800 Resolve
(First
(Expressions
(N
)), Standard_String
);
11802 when Attribute_Wide_Value
=>
11803 Resolve
(First
(Expressions
(N
)), Standard_Wide_String
);
11805 when Attribute_Wide_Wide_Value
=>
11806 Resolve
(First
(Expressions
(N
)), Standard_Wide_Wide_String
);
11808 when others => null;
11811 -- If the prefix of the attribute is a class-wide type then it
11812 -- will be expanded into a dispatching call to a predefined
11813 -- primitive. Therefore we must check for potential violation
11814 -- of such restriction.
11816 if Is_Class_Wide_Type
(Etype
(P
)) then
11817 Check_Restriction
(No_Dispatching_Calls
, N
);
11821 -- Mark use clauses of the original prefix if the attribute is applied
11824 if Nkind
(Original_Node
(P
)) in N_Has_Entity
11825 and then Present
(Entity
(Original_Node
(P
)))
11827 Mark_Use_Clauses
(Original_Node
(P
));
11830 -- Normally the Freezing is done by Resolve but sometimes the Prefix
11831 -- is not resolved, in which case the freezing must be done now.
11833 -- For an elaboration check on a subprogram, we do not freeze its type.
11834 -- It may be declared in an unrelated scope, in particular in the case
11835 -- of a generic function whose type may remain unelaborated.
11837 if Attr_Id
= Attribute_Elaborated
then
11841 Freeze_Expression
(P
);
11844 -- Finally perform static evaluation on the attribute reference
11846 Analyze_Dimension
(N
);
11847 Eval_Attribute
(N
);
11848 end Resolve_Attribute
;
11850 ------------------------
11851 -- Set_Boolean_Result --
11852 ------------------------
11854 procedure Set_Boolean_Result
(N
: Node_Id
; B
: Boolean) is
11855 Loc
: constant Source_Ptr
:= Sloc
(N
);
11858 Rewrite
(N
, New_Occurrence_Of
(Standard_True
, Loc
));
11860 Rewrite
(N
, New_Occurrence_Of
(Standard_False
, Loc
));
11862 end Set_Boolean_Result
;
11864 -------------------------------
11865 -- Statically_Denotes_Object --
11866 -------------------------------
11868 function Statically_Denotes_Object
(N
: Node_Id
) return Boolean is
11872 if Is_Entity_Name
(N
) then
11875 elsif Nkind
(N
) = N_Selected_Component
11876 and then Statically_Denotes_Object
(Prefix
(N
))
11877 and then Present
(Entity
(Selector_Name
(N
)))
11880 Sel_Id
: constant Entity_Id
:= Entity
(Selector_Name
(N
));
11881 Comp_Decl
: constant Node_Id
:= Parent
(Sel_Id
);
11884 if Depends_On_Discriminant
(Sel_Id
) then
11887 elsif Nkind
(Parent
(Parent
(Comp_Decl
))) = N_Variant
then
11895 elsif Nkind
(N
) = N_Indexed_Component
11896 and then Statically_Denotes_Object
(Prefix
(N
))
11897 and then Is_Constrained
(Etype
(Prefix
(N
)))
11899 Indx
:= First
(Expressions
(N
));
11900 while Present
(Indx
) loop
11901 if not Compile_Time_Known_Value
(Indx
)
11902 or else Do_Range_Check
(Indx
)
11915 end Statically_Denotes_Object
;
11917 --------------------------------
11918 -- Stream_Attribute_Available --
11919 --------------------------------
11921 function Stream_Attribute_Available
11923 Nam
: TSS_Name_Type
;
11924 Partial_View
: Node_Id
:= Empty
) return Boolean
11926 Etyp
: Entity_Id
:= Typ
;
11928 -- Start of processing for Stream_Attribute_Available
11931 -- We need some comments in this body ???
11933 if Has_Stream_Attribute_Definition
(Typ
, Nam
) then
11937 if Is_Class_Wide_Type
(Typ
) then
11938 return not Is_Limited_Type
(Typ
)
11939 or else Stream_Attribute_Available
(Etype
(Typ
), Nam
);
11942 if Nam
= TSS_Stream_Input
11943 and then Is_Abstract_Type
(Typ
)
11944 and then not Is_Class_Wide_Type
(Typ
)
11949 if not (Is_Limited_Type
(Typ
)
11950 or else (Present
(Partial_View
)
11951 and then Is_Limited_Type
(Partial_View
)))
11956 -- In Ada 2005, Input can invoke Read, and Output can invoke Write
11958 if Nam
= TSS_Stream_Input
11959 and then Ada_Version
>= Ada_2005
11960 and then Stream_Attribute_Available
(Etyp
, TSS_Stream_Read
)
11964 elsif Nam
= TSS_Stream_Output
11965 and then Ada_Version
>= Ada_2005
11966 and then Stream_Attribute_Available
(Etyp
, TSS_Stream_Write
)
11971 -- Case of Read and Write: check for attribute definition clause that
11972 -- applies to an ancestor type.
11974 while Etype
(Etyp
) /= Etyp
loop
11975 Etyp
:= Etype
(Etyp
);
11977 if Has_Stream_Attribute_Definition
(Etyp
, Nam
) then
11982 if Ada_Version
< Ada_2005
then
11984 -- In Ada 95 mode, also consider a non-visible definition
11987 Btyp
: constant Entity_Id
:= Implementation_Base_Type
(Typ
);
11990 and then Stream_Attribute_Available
11991 (Btyp
, Nam
, Partial_View
=> Typ
);
11996 end Stream_Attribute_Available
;