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
821 -- Save the scenario for later examination by the ABE Processing
824 Record_Elaboration_Scenario
(N
);
826 -- Case of access to subprogram
828 if Is_Entity_Name
(P
) and then Is_Overloadable
(Entity
(P
)) then
829 if Has_Pragma_Inline_Always
(Entity
(P
)) then
831 ("prefix of % attribute cannot be Inline_Always subprogram");
833 elsif Aname
= Name_Unchecked_Access
then
834 Error_Attr
("attribute% cannot be applied to a subprogram", P
);
837 -- Issue an error if the prefix denotes an eliminated subprogram
839 Check_For_Eliminated_Subprogram
(P
, Entity
(P
));
841 -- Check for obsolescent subprogram reference
843 Check_Obsolescent_2005_Entity
(Entity
(P
), P
);
845 -- Build the appropriate subprogram type
847 Build_Access_Subprogram_Type
(P
);
849 -- For P'Access or P'Unrestricted_Access, where P is a nested
850 -- subprogram, we might be passing P to another subprogram (but we
851 -- don't check that here), which might call P. P could modify
852 -- local variables, so we need to kill current values. It is
853 -- important not to do this for library-level subprograms, because
854 -- Kill_Current_Values is very inefficient in the case of library
855 -- level packages with lots of tagged types.
857 if Is_Library_Level_Entity
(Entity
(Prefix
(N
))) then
860 -- Do not kill values on nodes initializing dispatch tables
861 -- slots. The construct Prim_Ptr!(Prim'Unrestricted_Access)
862 -- is currently generated by the expander only for this
863 -- purpose. Done to keep the quality of warnings currently
864 -- generated by the compiler (otherwise any declaration of
865 -- a tagged type cleans constant indications from its scope).
867 elsif Nkind
(Parent
(N
)) = N_Unchecked_Type_Conversion
868 and then (Etype
(Parent
(N
)) = RTE
(RE_Prim_Ptr
)
870 Etype
(Parent
(N
)) = RTE
(RE_Size_Ptr
))
871 and then Is_Dispatching_Operation
872 (Directly_Designated_Type
(Etype
(N
)))
880 -- In the static elaboration model, treat the attribute reference
881 -- as a subprogram call for elaboration purposes. Suppress this
882 -- treatment under debug flag. In any case, we are all done.
884 if Legacy_Elaboration_Checks
885 and not Dynamic_Elaboration_Checks
886 and not Debug_Flag_Dot_UU
893 -- Component is an operation of a protected type
895 elsif Nkind
(P
) = N_Selected_Component
896 and then Is_Overloadable
(Entity
(Selector_Name
(P
)))
898 if Ekind
(Entity
(Selector_Name
(P
))) = E_Entry
then
899 Error_Attr_P
("prefix of % attribute must be subprogram");
902 Build_Access_Subprogram_Type
(Selector_Name
(P
));
906 -- Deal with incorrect reference to a type, but note that some
907 -- accesses are allowed: references to the current type instance,
908 -- or in Ada 2005 self-referential pointer in a default-initialized
911 if Is_Entity_Name
(P
) then
914 -- The reference may appear in an aggregate that has been expanded
915 -- into a loop. Locate scope of type definition, if any.
917 Scop
:= Current_Scope
;
918 while Ekind
(Scop
) = E_Loop
loop
919 Scop
:= Scope
(Scop
);
922 if Is_Type
(Typ
) then
924 -- OK if we are within the scope of a limited type
925 -- let's mark the component as having per object constraint
927 if Is_Anonymous_Tagged_Base
(Scop
, Typ
) then
935 Q
: Node_Id
:= Parent
(N
);
939 and then Nkind
(Q
) /= N_Component_Declaration
945 Set_Has_Per_Object_Constraint
946 (Defining_Identifier
(Q
), True);
950 if Nkind
(P
) = N_Expanded_Name
then
952 ("current instance prefix must be a direct name", P
);
955 -- If a current instance attribute appears in a component
956 -- constraint it must appear alone; other contexts (spec-
957 -- expressions, within a task body) are not subject to this
960 if not In_Spec_Expression
961 and then not Has_Completion
(Scop
)
963 Nkind_In
(Parent
(N
), N_Discriminant_Association
,
964 N_Index_Or_Discriminant_Constraint
)
967 ("current instance attribute must appear alone", N
);
970 if Is_CPP_Class
(Root_Type
(Typ
)) then
972 ("??current instance unsupported for derivations of "
973 & "'C'P'P types", N
);
976 -- OK if we are in initialization procedure for the type
977 -- in question, in which case the reference to the type
978 -- is rewritten as a reference to the current object.
980 elsif Ekind
(Scop
) = E_Procedure
981 and then Is_Init_Proc
(Scop
)
982 and then Etype
(First_Formal
(Scop
)) = Typ
985 Make_Attribute_Reference
(Loc
,
986 Prefix
=> Make_Identifier
(Loc
, Name_uInit
),
987 Attribute_Name
=> Name_Unrestricted_Access
));
991 -- OK if a task type, this test needs sharpening up ???
993 elsif Is_Task_Type
(Typ
) then
996 -- OK if self-reference in an aggregate in Ada 2005, and
997 -- the reference comes from a copied default expression.
999 -- Note that we check legality of self-reference even if the
1000 -- expression comes from source, e.g. when a single component
1001 -- association in an aggregate has a box association.
1003 elsif Ada_Version
>= Ada_2005
1004 and then OK_Self_Reference
1008 -- OK if reference to current instance of a protected object
1010 elsif Is_Protected_Self_Reference
(P
) then
1013 -- Otherwise we have an error case
1016 Error_Attr
("% attribute cannot be applied to type", P
);
1022 -- If we fall through, we have a normal access to object case
1024 -- Unrestricted_Access is (for now) legal wherever an allocator would
1025 -- be legal, so its Etype is set to E_Allocator. The expected type
1026 -- of the other attributes is a general access type, and therefore
1027 -- we label them with E_Access_Attribute_Type.
1029 if not Is_Overloaded
(P
) then
1030 Acc_Type
:= Build_Access_Object_Type
(P_Type
);
1031 Set_Etype
(N
, Acc_Type
);
1035 Index
: Interp_Index
;
1038 Set_Etype
(N
, Any_Type
);
1039 Get_First_Interp
(P
, Index
, It
);
1040 while Present
(It
.Typ
) loop
1041 Acc_Type
:= Build_Access_Object_Type
(It
.Typ
);
1042 Add_One_Interp
(N
, Acc_Type
, Acc_Type
);
1043 Get_Next_Interp
(Index
, It
);
1048 -- Special cases when we can find a prefix that is an entity name
1057 if Is_Entity_Name
(PP
) then
1060 -- If we have an access to an object, and the attribute
1061 -- comes from source, then set the object as potentially
1062 -- source modified. We do this because the resulting access
1063 -- pointer can be used to modify the variable, and we might
1064 -- not detect this, leading to some junk warnings.
1066 -- We only do this for source references, since otherwise
1067 -- we can suppress warnings, e.g. from the unrestricted
1068 -- access generated for validity checks in -gnatVa mode.
1070 if Comes_From_Source
(N
) then
1071 Set_Never_Set_In_Source
(Ent
, False);
1074 -- Mark entity as address taken in the case of
1075 -- 'Unrestricted_Access or subprograms, and kill current
1078 if Aname
= Name_Unrestricted_Access
1079 or else Is_Subprogram
(Ent
)
1081 Set_Address_Taken
(Ent
);
1084 Kill_Current_Values
(Ent
);
1087 elsif Nkind_In
(PP
, N_Selected_Component
,
1088 N_Indexed_Component
)
1097 end Analyze_Access_Attribute
;
1099 ----------------------------------
1100 -- Analyze_Attribute_Old_Result --
1101 ----------------------------------
1103 procedure Analyze_Attribute_Old_Result
1104 (Legal
: out Boolean;
1105 Spec_Id
: out Entity_Id
)
1107 procedure Check_Placement_In_Check
(Prag
: Node_Id
);
1108 -- Verify that the attribute appears within pragma Check that mimics
1111 procedure Check_Placement_In_Contract_Cases
(Prag
: Node_Id
);
1112 -- Verify that the attribute appears within a consequence of aspect
1113 -- or pragma Contract_Cases denoted by Prag.
1115 procedure Check_Placement_In_Test_Case
(Prag
: Node_Id
);
1116 -- Verify that the attribute appears within the "Ensures" argument of
1117 -- aspect or pragma Test_Case denoted by Prag.
1121 Encl_Nod
: Node_Id
) return Boolean;
1122 -- Subsidiary to Check_Placemenet_In_XXX. Determine whether arbitrary
1123 -- node Nod is within enclosing node Encl_Nod.
1125 procedure Placement_Error
;
1126 pragma No_Return
(Placement_Error
);
1127 -- Emit a general error when the attributes does not appear in a
1128 -- postcondition-like aspect or pragma, and then raises Bad_Attribute
1129 -- to avoid any further semantic processing.
1131 ------------------------------
1132 -- Check_Placement_In_Check --
1133 ------------------------------
1135 procedure Check_Placement_In_Check
(Prag
: Node_Id
) is
1136 Args
: constant List_Id
:= Pragma_Argument_Associations
(Prag
);
1137 Nam
: constant Name_Id
:= Chars
(Get_Pragma_Arg
(First
(Args
)));
1140 -- The "Name" argument of pragma Check denotes a postcondition
1142 if Nam_In
(Nam
, Name_Post
,
1149 -- Otherwise the placement of the attribute is illegal
1154 end Check_Placement_In_Check
;
1156 ---------------------------------------
1157 -- Check_Placement_In_Contract_Cases --
1158 ---------------------------------------
1160 procedure Check_Placement_In_Contract_Cases
(Prag
: Node_Id
) is
1166 -- Obtain the argument of the aspect or pragma
1168 if Nkind
(Prag
) = N_Aspect_Specification
then
1171 Arg
:= First
(Pragma_Argument_Associations
(Prag
));
1174 Cases
:= Expression
(Arg
);
1176 if Present
(Component_Associations
(Cases
)) then
1177 CCase
:= First
(Component_Associations
(Cases
));
1178 while Present
(CCase
) loop
1180 -- Detect whether the attribute appears within the
1181 -- consequence of the current contract case.
1183 if Nkind
(CCase
) = N_Component_Association
1184 and then Is_Within
(N
, Expression
(CCase
))
1193 -- Otherwise aspect or pragma Contract_Cases is either malformed
1194 -- or the attribute does not appear within a consequence.
1197 ("attribute % must appear in the consequence of a contract case",
1199 end Check_Placement_In_Contract_Cases
;
1201 ----------------------------------
1202 -- Check_Placement_In_Test_Case --
1203 ----------------------------------
1205 procedure Check_Placement_In_Test_Case
(Prag
: Node_Id
) is
1206 Arg
: constant Node_Id
:=
1209 Arg_Nam
=> Name_Ensures
,
1210 From_Aspect
=> Nkind
(Prag
) = N_Aspect_Specification
);
1213 -- Detect whether the attribute appears within the "Ensures"
1214 -- expression of aspect or pragma Test_Case.
1216 if Present
(Arg
) and then Is_Within
(N
, Arg
) then
1221 ("attribute % must appear in the ensures expression of a "
1224 end Check_Placement_In_Test_Case
;
1232 Encl_Nod
: Node_Id
) return Boolean
1238 while Present
(Par
) loop
1239 if Par
= Encl_Nod
then
1242 -- Prevent the search from going too far
1244 elsif Is_Body_Or_Package_Declaration
(Par
) then
1248 Par
:= Parent
(Par
);
1254 ---------------------
1255 -- Placement_Error --
1256 ---------------------
1258 procedure Placement_Error
is
1260 if Aname
= Name_Old
then
1261 Error_Attr
("attribute % can only appear in postcondition", P
);
1263 -- Specialize the error message for attribute 'Result
1267 ("attribute % can only appear in postcondition of function",
1270 end Placement_Error
;
1276 Subp_Decl
: Node_Id
;
1278 -- Start of processing for Analyze_Attribute_Old_Result
1281 -- Assume that the attribute is illegal
1286 -- Traverse the parent chain to find the aspect or pragma where the
1287 -- attribute resides.
1290 while Present
(Prag
) loop
1291 if Nkind_In
(Prag
, N_Aspect_Specification
, N_Pragma
) then
1294 -- Prevent the search from going too far
1296 elsif Is_Body_Or_Package_Declaration
(Prag
) then
1300 Prag
:= Parent
(Prag
);
1303 -- The attribute is allowed to appear only in postcondition-like
1304 -- aspects or pragmas.
1306 if Nkind_In
(Prag
, N_Aspect_Specification
, N_Pragma
) then
1307 if Nkind
(Prag
) = N_Aspect_Specification
then
1308 Prag_Nam
:= Chars
(Identifier
(Prag
));
1310 Prag_Nam
:= Pragma_Name
(Prag
);
1313 if Prag_Nam
= Name_Check
then
1314 Check_Placement_In_Check
(Prag
);
1316 elsif Prag_Nam
= Name_Contract_Cases
then
1317 Check_Placement_In_Contract_Cases
(Prag
);
1319 -- Attribute 'Result is allowed to appear in aspect or pragma
1320 -- [Refined_]Depends (SPARK RM 6.1.5(11)).
1322 elsif Nam_In
(Prag_Nam
, Name_Depends
, Name_Refined_Depends
)
1323 and then Aname
= Name_Result
1327 elsif Nam_In
(Prag_Nam
, Name_Post
,
1334 elsif Prag_Nam
= Name_Test_Case
then
1335 Check_Placement_In_Test_Case
(Prag
);
1342 -- Otherwise the placement of the attribute is illegal
1349 -- Find the related subprogram subject to the aspect or pragma
1351 if Nkind
(Prag
) = N_Aspect_Specification
then
1352 Subp_Decl
:= Parent
(Prag
);
1354 Subp_Decl
:= Find_Related_Declaration_Or_Body
(Prag
);
1357 -- The aspect or pragma where the attribute resides should be
1358 -- associated with a subprogram declaration or a body. If this is not
1359 -- the case, then the aspect or pragma is illegal. Return as analysis
1360 -- cannot be carried out. Note that it is legal to have the aspect
1361 -- appear on a subprogram renaming, when the renamed entity is an
1362 -- attribute reference.
1364 -- Generating C code the internally built nested _postcondition
1365 -- subprograms are inlined; after expanded, inlined aspects are
1366 -- located in the internal block generated by the frontend.
1368 if Nkind
(Subp_Decl
) = N_Block_Statement
1369 and then Modify_Tree_For_C
1370 and then In_Inlined_Body
1374 elsif not Nkind_In
(Subp_Decl
, N_Abstract_Subprogram_Declaration
,
1375 N_Entry_Declaration
,
1376 N_Expression_Function
,
1377 N_Generic_Subprogram_Declaration
,
1379 N_Subprogram_Body_Stub
,
1380 N_Subprogram_Declaration
,
1381 N_Subprogram_Renaming_Declaration
)
1386 -- If we get here, then the attribute is legal
1389 Spec_Id
:= Unique_Defining_Entity
(Subp_Decl
);
1391 -- When generating C code, nested _postcondition subprograms are
1392 -- inlined by the front end to avoid problems (when unnested) with
1393 -- referenced itypes. Handle that here, since as part of inlining the
1394 -- expander nests subprogram within a dummy procedure named _parent
1395 -- (see Build_Postconditions_Procedure and Build_Body_To_Inline).
1396 -- Hence, in this context, the spec_id of _postconditions is the
1399 if Modify_Tree_For_C
1400 and then Chars
(Spec_Id
) = Name_uParent
1401 and then Chars
(Scope
(Spec_Id
)) = Name_uPostconditions
1403 -- This situation occurs only when preanalyzing the inlined body
1405 pragma Assert
(not Full_Analysis
);
1407 Spec_Id
:= Scope
(Spec_Id
);
1408 pragma Assert
(Is_Inlined
(Spec_Id
));
1410 end Analyze_Attribute_Old_Result
;
1412 -----------------------------
1413 -- Analyze_Image_Attribute --
1414 -----------------------------
1416 procedure Analyze_Image_Attribute
(Str_Typ
: Entity_Id
) is
1418 Check_SPARK_05_Restriction_On_Attribute
;
1420 -- AI12-00124: The ARG has adopted the GNAT semantics of 'Img for
1421 -- scalar types, so that the prefix can be an object, a named value,
1422 -- or a type, and there is no need for an argument in this case.
1424 if Attr_Id
= Attribute_Img
1425 or else (Ada_Version
> Ada_2005
and then Is_Object_Image
(P
))
1428 Set_Etype
(N
, Str_Typ
);
1430 if Attr_Id
= Attribute_Img
and then not Is_Object_Image
(P
) then
1432 ("prefix of % attribute must be a scalar object name");
1436 Set_Etype
(N
, Str_Typ
);
1438 -- Check that the prefix type is scalar - much in the same way as
1439 -- Check_Scalar_Type but with custom error messages to denote the
1440 -- variants of 'Image attributes.
1442 if Is_Entity_Name
(P
)
1443 and then Is_Type
(Entity
(P
))
1444 and then Ekind
(Entity
(P
)) = E_Incomplete_Type
1445 and then Present
(Full_View
(Entity
(P
)))
1447 P_Type
:= Full_View
(Entity
(P
));
1448 Set_Entity
(P
, P_Type
);
1451 if not Is_Entity_Name
(P
)
1452 or else not Is_Type
(Entity
(P
))
1453 or else not Is_Scalar_Type
(P_Type
)
1455 if Ada_Version
> Ada_2005
then
1457 ("prefix of % attribute must be a scalar type or a scalar "
1460 Error_Attr_P
("prefix of % attribute must be a scalar type");
1463 elsif Is_Protected_Self_Reference
(P
) then
1465 ("prefix of % attribute denotes current instance "
1466 & "(RM 9.4(21/2))");
1469 Resolve
(E1
, P_Base_Type
);
1470 Validate_Non_Static_Attribute_Function_Call
;
1475 -- Check restriction No_Fixed_IO. Note the check of Comes_From_Source
1476 -- to avoid giving a duplicate message for when Image attributes
1477 -- applied to object references get expanded into type-based Image
1480 if Restriction_Check_Required
(No_Fixed_IO
)
1481 and then Comes_From_Source
(N
)
1482 and then Is_Fixed_Point_Type
(P_Type
)
1484 Check_Restriction
(No_Fixed_IO
, P
);
1486 end Analyze_Image_Attribute
;
1488 ---------------------------------
1489 -- Bad_Attribute_For_Predicate --
1490 ---------------------------------
1492 procedure Bad_Attribute_For_Predicate
is
1494 if Is_Scalar_Type
(P_Type
)
1495 and then Comes_From_Source
(N
)
1497 Error_Msg_Name_1
:= Aname
;
1498 Bad_Predicated_Subtype_Use
1499 ("type& has predicates, attribute % not allowed", N
, P_Type
);
1501 end Bad_Attribute_For_Predicate
;
1503 --------------------------------
1504 -- Check_Array_Or_Scalar_Type --
1505 --------------------------------
1507 procedure Check_Array_Or_Scalar_Type
is
1508 function In_Aspect_Specification
return Boolean;
1509 -- A current instance of a type in an aspect specification is an
1510 -- object and not a type, and therefore cannot be of a scalar type
1511 -- in the prefix of one of the array attributes if the attribute
1512 -- reference is part of an aspect expression.
1514 -----------------------------
1515 -- In_Aspect_Specification --
1516 -----------------------------
1518 function In_Aspect_Specification
return Boolean is
1523 while Present
(P
) loop
1524 if Nkind
(P
) = N_Aspect_Specification
then
1525 return P_Type
= Entity
(P
);
1527 elsif Nkind
(P
) in N_Declaration
then
1535 end In_Aspect_Specification
;
1542 -- Start of processing for Check_Array_Or_Scalar_Type
1545 -- Case of string literal or string literal subtype. These cases
1546 -- cannot arise from legal Ada code, but the expander is allowed
1547 -- to generate them. They require special handling because string
1548 -- literal subtypes do not have standard bounds (the whole idea
1549 -- of these subtypes is to avoid having to generate the bounds)
1551 if Ekind
(P_Type
) = E_String_Literal_Subtype
then
1552 Set_Etype
(N
, Etype
(First_Index
(P_Base_Type
)));
1557 elsif Is_Scalar_Type
(P_Type
) then
1560 if Present
(E1
) then
1561 Error_Attr
("invalid argument in % attribute", E1
);
1563 elsif In_Aspect_Specification
then
1565 ("prefix of % attribute cannot be the current instance of a "
1566 & "scalar type", P
);
1569 Set_Etype
(N
, P_Base_Type
);
1573 -- The following is a special test to allow 'First to apply to
1574 -- private scalar types if the attribute comes from generated
1575 -- code. This occurs in the case of Normalize_Scalars code.
1577 elsif Is_Private_Type
(P_Type
)
1578 and then Present
(Full_View
(P_Type
))
1579 and then Is_Scalar_Type
(Full_View
(P_Type
))
1580 and then not Comes_From_Source
(N
)
1582 Set_Etype
(N
, Implementation_Base_Type
(P_Type
));
1584 -- Array types other than string literal subtypes handled above
1589 -- We know prefix is an array type, or the name of an array
1590 -- object, and that the expression, if present, is static
1591 -- and within the range of the dimensions of the type.
1593 pragma Assert
(Is_Array_Type
(P_Type
));
1594 Index
:= First_Index
(P_Base_Type
);
1598 -- First dimension assumed
1600 Set_Etype
(N
, Base_Type
(Etype
(Index
)));
1603 Dims
:= UI_To_Int
(Intval
(E1
));
1605 for J
in 1 .. Dims
- 1 loop
1609 Set_Etype
(N
, Base_Type
(Etype
(Index
)));
1610 Set_Etype
(E1
, Standard_Integer
);
1613 end Check_Array_Or_Scalar_Type
;
1615 ----------------------
1616 -- Check_Array_Type --
1617 ----------------------
1619 procedure Check_Array_Type
is
1621 -- Dimension number for array attributes
1624 -- If the type is a string literal type, then this must be generated
1625 -- internally, and no further check is required on its legality.
1627 if Ekind
(P_Type
) = E_String_Literal_Subtype
then
1630 -- If the type is a composite, it is an illegal aggregate, no point
1633 elsif P_Type
= Any_Composite
then
1634 raise Bad_Attribute
;
1637 -- Normal case of array type or subtype
1639 Check_Either_E0_Or_E1
;
1642 if Is_Array_Type
(P_Type
) then
1643 if not Is_Constrained
(P_Type
)
1644 and then Is_Entity_Name
(P
)
1645 and then Is_Type
(Entity
(P
))
1647 -- Note: we do not call Error_Attr here, since we prefer to
1648 -- continue, using the relevant index type of the array,
1649 -- even though it is unconstrained. This gives better error
1650 -- recovery behavior.
1652 Error_Msg_Name_1
:= Aname
;
1654 ("prefix for % attribute must be constrained array", P
);
1657 -- The attribute reference freezes the type, and thus the
1658 -- component type, even if the attribute may not depend on the
1659 -- component. Diagnose arrays with incomplete components now.
1660 -- If the prefix is an access to array, this does not freeze
1661 -- the designated type.
1663 if Nkind
(P
) /= N_Explicit_Dereference
then
1664 Check_Fully_Declared
(Component_Type
(P_Type
), P
);
1667 D
:= Number_Dimensions
(P_Type
);
1670 if Is_Private_Type
(P_Type
) then
1671 Error_Attr_P
("prefix for % attribute may not be private type");
1673 elsif Is_Access_Type
(P_Type
)
1674 and then Is_Array_Type
(Designated_Type
(P_Type
))
1675 and then Is_Entity_Name
(P
)
1676 and then Is_Type
(Entity
(P
))
1678 Error_Attr_P
("prefix of % attribute cannot be access type");
1680 elsif Attr_Id
= Attribute_First
1682 Attr_Id
= Attribute_Last
1684 Error_Attr
("invalid prefix for % attribute", P
);
1687 Error_Attr_P
("prefix for % attribute must be array");
1691 if Present
(E1
) then
1692 Resolve
(E1
, Any_Integer
);
1693 Set_Etype
(E1
, Standard_Integer
);
1695 if not Is_OK_Static_Expression
(E1
)
1696 or else Raises_Constraint_Error
(E1
)
1698 Flag_Non_Static_Expr
1699 ("expression for dimension must be static!", E1
);
1702 elsif UI_To_Int
(Expr_Value
(E1
)) > D
1703 or else UI_To_Int
(Expr_Value
(E1
)) < 1
1705 Error_Attr
("invalid dimension number for array type", E1
);
1709 if (Style_Check
and Style_Check_Array_Attribute_Index
)
1710 and then Comes_From_Source
(N
)
1712 Style
.Check_Array_Attribute_Index
(N
, E1
, D
);
1714 end Check_Array_Type
;
1716 -------------------------
1717 -- Check_Asm_Attribute --
1718 -------------------------
1720 procedure Check_Asm_Attribute
is
1725 -- Check first argument is static string expression
1727 Analyze_And_Resolve
(E1
, Standard_String
);
1729 if Etype
(E1
) = Any_Type
then
1732 elsif not Is_OK_Static_Expression
(E1
) then
1733 Flag_Non_Static_Expr
1734 ("constraint argument must be static string expression!", E1
);
1738 -- Check second argument is right type
1740 Analyze_And_Resolve
(E2
, Entity
(P
));
1742 -- Note: that is all we need to do, we don't need to check
1743 -- that it appears in a correct context. The Ada type system
1744 -- will do that for us.
1746 end Check_Asm_Attribute
;
1748 ---------------------
1749 -- Check_Component --
1750 ---------------------
1752 procedure Check_Component
is
1756 if Nkind
(P
) /= N_Selected_Component
1758 (Ekind
(Entity
(Selector_Name
(P
))) /= E_Component
1760 Ekind
(Entity
(Selector_Name
(P
))) /= E_Discriminant
)
1762 Error_Attr_P
("prefix for % attribute must be selected component");
1764 end Check_Component
;
1766 ------------------------------------
1767 -- Check_Decimal_Fixed_Point_Type --
1768 ------------------------------------
1770 procedure Check_Decimal_Fixed_Point_Type
is
1774 if not Is_Decimal_Fixed_Point_Type
(P_Type
) then
1775 Error_Attr_P
("prefix of % attribute must be decimal type");
1777 end Check_Decimal_Fixed_Point_Type
;
1779 -----------------------
1780 -- Check_Dereference --
1781 -----------------------
1783 procedure Check_Dereference
is
1786 -- Case of a subtype mark
1788 if Is_Entity_Name
(P
) and then Is_Type
(Entity
(P
)) then
1792 -- Case of an expression
1796 if Is_Access_Type
(P_Type
) then
1798 -- If there is an implicit dereference, then we must freeze the
1799 -- designated type of the access type, since the type of the
1800 -- referenced array is this type (see AI95-00106).
1802 -- As done elsewhere, freezing must not happen when preanalyzing
1803 -- a pre- or postcondition or a default value for an object or for
1804 -- a formal parameter.
1806 if not In_Spec_Expression
then
1807 Freeze_Before
(N
, Designated_Type
(P_Type
));
1811 Make_Explicit_Dereference
(Sloc
(P
),
1812 Prefix
=> Relocate_Node
(P
)));
1814 Analyze_And_Resolve
(P
);
1815 P_Type
:= Etype
(P
);
1817 if P_Type
= Any_Type
then
1818 raise Bad_Attribute
;
1821 P_Base_Type
:= Base_Type
(P_Type
);
1823 end Check_Dereference
;
1825 -------------------------
1826 -- Check_Discrete_Type --
1827 -------------------------
1829 procedure Check_Discrete_Type
is
1833 if not Is_Discrete_Type
(P_Type
) then
1834 Error_Attr_P
("prefix of % attribute must be discrete type");
1836 end Check_Discrete_Type
;
1842 procedure Check_E0
is
1844 if Present
(E1
) then
1845 Unexpected_Argument
(E1
);
1853 procedure Check_E1
is
1855 Check_Either_E0_Or_E1
;
1859 -- Special-case attributes that are functions and that appear as
1860 -- the prefix of another attribute. Error is posted on parent.
1862 if Nkind
(Parent
(N
)) = N_Attribute_Reference
1863 and then Nam_In
(Attribute_Name
(Parent
(N
)), Name_Address
,
1867 Error_Msg_Name_1
:= Attribute_Name
(Parent
(N
));
1868 Error_Msg_N
("illegal prefix for % attribute", Parent
(N
));
1869 Set_Etype
(Parent
(N
), Any_Type
);
1870 Set_Entity
(Parent
(N
), Any_Type
);
1871 raise Bad_Attribute
;
1874 Error_Attr
("missing argument for % attribute", N
);
1883 procedure Check_E2
is
1886 Error_Attr
("missing arguments for % attribute (2 required)", N
);
1888 Error_Attr
("missing argument for % attribute (2 required)", N
);
1892 ---------------------------
1893 -- Check_Either_E0_Or_E1 --
1894 ---------------------------
1896 procedure Check_Either_E0_Or_E1
is
1898 if Present
(E2
) then
1899 Unexpected_Argument
(E2
);
1901 end Check_Either_E0_Or_E1
;
1903 ----------------------
1904 -- Check_Enum_Image --
1905 ----------------------
1907 procedure Check_Enum_Image
is
1911 -- When an enumeration type appears in an attribute reference, all
1912 -- literals of the type are marked as referenced. This must only be
1913 -- done if the attribute reference appears in the current source.
1914 -- Otherwise the information on references may differ between a
1915 -- normal compilation and one that performs inlining.
1917 if Is_Enumeration_Type
(P_Base_Type
)
1918 and then In_Extended_Main_Code_Unit
(N
)
1920 Lit
:= First_Literal
(P_Base_Type
);
1921 while Present
(Lit
) loop
1922 Set_Referenced
(Lit
);
1926 end Check_Enum_Image
;
1928 ----------------------------
1929 -- Check_First_Last_Valid --
1930 ----------------------------
1932 procedure Check_First_Last_Valid
is
1934 Check_Discrete_Type
;
1936 -- Freeze the subtype now, so that the following test for predicates
1937 -- works (we set the predicates stuff up at freeze time)
1939 Insert_Actions
(N
, Freeze_Entity
(P_Type
, P
));
1941 -- Now test for dynamic predicate
1943 if Has_Predicates
(P_Type
)
1944 and then not (Has_Static_Predicate
(P_Type
))
1947 ("prefix of % attribute may not have dynamic predicate");
1950 -- Check non-static subtype
1952 if not Is_OK_Static_Subtype
(P_Type
) then
1953 Error_Attr_P
("prefix of % attribute must be a static subtype");
1956 -- Test case for no values
1958 if Expr_Value
(Type_Low_Bound
(P_Type
)) >
1959 Expr_Value
(Type_High_Bound
(P_Type
))
1960 or else (Has_Predicates
(P_Type
)
1962 Is_Empty_List
(Static_Discrete_Predicate
(P_Type
)))
1965 ("prefix of % attribute must be subtype with at least one "
1968 end Check_First_Last_Valid
;
1970 ----------------------------
1971 -- Check_Fixed_Point_Type --
1972 ----------------------------
1974 procedure Check_Fixed_Point_Type
is
1978 if not Is_Fixed_Point_Type
(P_Type
) then
1979 Error_Attr_P
("prefix of % attribute must be fixed point type");
1981 end Check_Fixed_Point_Type
;
1983 ------------------------------
1984 -- Check_Fixed_Point_Type_0 --
1985 ------------------------------
1987 procedure Check_Fixed_Point_Type_0
is
1989 Check_Fixed_Point_Type
;
1991 end Check_Fixed_Point_Type_0
;
1993 -------------------------------
1994 -- Check_Floating_Point_Type --
1995 -------------------------------
1997 procedure Check_Floating_Point_Type
is
2001 if not Is_Floating_Point_Type
(P_Type
) then
2002 Error_Attr_P
("prefix of % attribute must be float type");
2004 end Check_Floating_Point_Type
;
2006 ---------------------------------
2007 -- Check_Floating_Point_Type_0 --
2008 ---------------------------------
2010 procedure Check_Floating_Point_Type_0
is
2012 Check_Floating_Point_Type
;
2014 end Check_Floating_Point_Type_0
;
2016 ---------------------------------
2017 -- Check_Floating_Point_Type_1 --
2018 ---------------------------------
2020 procedure Check_Floating_Point_Type_1
is
2022 Check_Floating_Point_Type
;
2024 end Check_Floating_Point_Type_1
;
2026 ---------------------------------
2027 -- Check_Floating_Point_Type_2 --
2028 ---------------------------------
2030 procedure Check_Floating_Point_Type_2
is
2032 Check_Floating_Point_Type
;
2034 end Check_Floating_Point_Type_2
;
2036 ------------------------
2037 -- Check_Integer_Type --
2038 ------------------------
2040 procedure Check_Integer_Type
is
2044 if not Is_Integer_Type
(P_Type
) then
2045 Error_Attr_P
("prefix of % attribute must be integer type");
2047 end Check_Integer_Type
;
2049 --------------------------------
2050 -- Check_Modular_Integer_Type --
2051 --------------------------------
2053 procedure Check_Modular_Integer_Type
is
2057 if not Is_Modular_Integer_Type
(P_Type
) then
2059 ("prefix of % attribute must be modular integer type");
2061 end Check_Modular_Integer_Type
;
2063 ------------------------
2064 -- Check_Not_CPP_Type --
2065 ------------------------
2067 procedure Check_Not_CPP_Type
is
2069 if Is_Tagged_Type
(Etype
(P
))
2070 and then Convention
(Etype
(P
)) = Convention_CPP
2071 and then Is_CPP_Class
(Root_Type
(Etype
(P
)))
2074 ("invalid use of % attribute with 'C'P'P tagged type");
2076 end Check_Not_CPP_Type
;
2078 -------------------------------
2079 -- Check_Not_Incomplete_Type --
2080 -------------------------------
2082 procedure Check_Not_Incomplete_Type
is
2087 -- Ada 2005 (AI-50217, AI-326): If the prefix is an explicit
2088 -- dereference we have to check wrong uses of incomplete types
2089 -- (other wrong uses are checked at their freezing point).
2091 -- In Ada 2012, incomplete types can appear in subprogram
2092 -- profiles, but formals with incomplete types cannot be the
2093 -- prefix of attributes.
2095 -- Example 1: Limited-with
2097 -- limited with Pkg;
2099 -- type Acc is access Pkg.T;
2101 -- S : Integer := X.all'Size; -- ERROR
2104 -- Example 2: Tagged incomplete
2106 -- type T is tagged;
2107 -- type Acc is access all T;
2109 -- S : constant Integer := X.all'Size; -- ERROR
2110 -- procedure Q (Obj : Integer := X.all'Alignment); -- ERROR
2112 if Ada_Version
>= Ada_2005
2113 and then Nkind
(P
) = N_Explicit_Dereference
2116 while Nkind
(E
) = N_Explicit_Dereference
loop
2122 if From_Limited_With
(Typ
) then
2124 ("prefix of % attribute cannot be an incomplete type");
2126 -- If the prefix is an access type check the designated type
2128 elsif Is_Access_Type
(Typ
)
2129 and then Nkind
(P
) = N_Explicit_Dereference
2131 Typ
:= Directly_Designated_Type
(Typ
);
2134 if Is_Class_Wide_Type
(Typ
) then
2135 Typ
:= Root_Type
(Typ
);
2138 -- A legal use of a shadow entity occurs only when the unit where
2139 -- the non-limited view resides is imported via a regular with
2140 -- clause in the current body. Such references to shadow entities
2141 -- may occur in subprogram formals.
2143 if Is_Incomplete_Type
(Typ
)
2144 and then From_Limited_With
(Typ
)
2145 and then Present
(Non_Limited_View
(Typ
))
2146 and then Is_Legal_Shadow_Entity_In_Body
(Typ
)
2148 Typ
:= Non_Limited_View
(Typ
);
2151 -- If still incomplete, it can be a local incomplete type, or a
2152 -- limited view whose scope is also a limited view.
2154 if Ekind
(Typ
) = E_Incomplete_Type
then
2155 if not From_Limited_With
(Typ
)
2156 and then No
(Full_View
(Typ
))
2159 ("prefix of % attribute cannot be an incomplete type");
2161 -- The limited view may be available indirectly through
2162 -- an intermediate unit. If the non-limited view is available
2163 -- the attribute reference is legal.
2165 elsif From_Limited_With
(Typ
)
2167 (No
(Non_Limited_View
(Typ
))
2168 or else Is_Incomplete_Type
(Non_Limited_View
(Typ
)))
2171 ("prefix of % attribute cannot be an incomplete type");
2175 -- Ada 2012 : formals in bodies may be incomplete, but no attribute
2178 elsif Is_Entity_Name
(P
)
2179 and then Is_Formal
(Entity
(P
))
2180 and then Is_Incomplete_Type
(Etype
(Etype
(P
)))
2183 ("prefix of % attribute cannot be an incomplete type");
2186 if not Is_Entity_Name
(P
)
2187 or else not Is_Type
(Entity
(P
))
2188 or else In_Spec_Expression
2192 Check_Fully_Declared
(P_Type
, P
);
2194 end Check_Not_Incomplete_Type
;
2196 ----------------------------
2197 -- Check_Object_Reference --
2198 ----------------------------
2200 procedure Check_Object_Reference
(P
: Node_Id
) is
2204 -- If we need an object, and we have a prefix that is the name of a
2205 -- function entity, convert it into a function call.
2207 if Is_Entity_Name
(P
)
2208 and then Ekind
(Entity
(P
)) = E_Function
2210 Rtyp
:= Etype
(Entity
(P
));
2213 Make_Function_Call
(Sloc
(P
),
2214 Name
=> Relocate_Node
(P
)));
2216 Analyze_And_Resolve
(P
, Rtyp
);
2218 -- Otherwise we must have an object reference
2220 elsif not Is_Object_Reference
(P
) then
2221 Error_Attr_P
("prefix of % attribute must be object");
2223 end Check_Object_Reference
;
2225 ----------------------------
2226 -- Check_PolyORB_Attribute --
2227 ----------------------------
2229 procedure Check_PolyORB_Attribute
is
2231 Validate_Non_Static_Attribute_Function_Call
;
2236 if Get_PCS_Name
/= Name_PolyORB_DSA
then
2238 ("attribute% requires the 'Poly'O'R'B 'P'C'S", N
);
2240 end Check_PolyORB_Attribute
;
2242 ------------------------
2243 -- Check_Program_Unit --
2244 ------------------------
2246 procedure Check_Program_Unit
is
2248 if Is_Entity_Name
(P
) then
2250 K
: constant Entity_Kind
:= Ekind
(Entity
(P
));
2251 T
: constant Entity_Id
:= Etype
(Entity
(P
));
2254 if K
in Subprogram_Kind
2255 or else K
in Task_Kind
2256 or else K
in Protected_Kind
2257 or else K
= E_Package
2258 or else K
in Generic_Unit_Kind
2259 or else (K
= E_Variable
2263 Is_Protected_Type
(T
)))
2270 Error_Attr_P
("prefix of % attribute must be program unit");
2271 end Check_Program_Unit
;
2273 ---------------------
2274 -- Check_Real_Type --
2275 ---------------------
2277 procedure Check_Real_Type
is
2281 if not Is_Real_Type
(P_Type
) then
2282 Error_Attr_P
("prefix of % attribute must be real type");
2284 end Check_Real_Type
;
2286 -----------------------
2287 -- Check_Scalar_Type --
2288 -----------------------
2290 procedure Check_Scalar_Type
is
2294 if not Is_Scalar_Type
(P_Type
) then
2295 Error_Attr_P
("prefix of % attribute must be scalar type");
2297 end Check_Scalar_Type
;
2299 ------------------------------------------
2300 -- Check_SPARK_05_Restriction_On_Attribute --
2301 ------------------------------------------
2303 procedure Check_SPARK_05_Restriction_On_Attribute
is
2305 Error_Msg_Name_1
:= Aname
;
2306 Check_SPARK_05_Restriction
("attribute % is not allowed", P
);
2307 end Check_SPARK_05_Restriction_On_Attribute
;
2309 ---------------------------
2310 -- Check_Standard_Prefix --
2311 ---------------------------
2313 procedure Check_Standard_Prefix
is
2317 if Nkind
(P
) /= N_Identifier
or else Chars
(P
) /= Name_Standard
then
2318 Error_Attr
("only allowed prefix for % attribute is Standard", P
);
2320 end Check_Standard_Prefix
;
2322 ----------------------------
2323 -- Check_Stream_Attribute --
2324 ----------------------------
2326 procedure Check_Stream_Attribute
(Nam
: TSS_Name_Type
) is
2330 In_Shared_Var_Procs
: Boolean;
2331 -- True when compiling System.Shared_Storage.Shared_Var_Procs body.
2332 -- For this runtime package (always compiled in GNAT mode), we allow
2333 -- stream attributes references for limited types for the case where
2334 -- shared passive objects are implemented using stream attributes,
2335 -- which is the default in GNAT's persistent storage implementation.
2338 Validate_Non_Static_Attribute_Function_Call
;
2340 -- With the exception of 'Input, Stream attributes are procedures,
2341 -- and can only appear at the position of procedure calls. We check
2342 -- for this here, before they are rewritten, to give a more precise
2345 if Nam
= TSS_Stream_Input
then
2348 elsif Is_List_Member
(N
)
2349 and then not Nkind_In
(Parent
(N
), N_Procedure_Call_Statement
,
2356 ("invalid context for attribute%, which is a procedure", N
);
2360 Btyp
:= Implementation_Base_Type
(P_Type
);
2362 -- Stream attributes not allowed on limited types unless the
2363 -- attribute reference was generated by the expander (in which
2364 -- case the underlying type will be used, as described in Sinfo),
2365 -- or the attribute was specified explicitly for the type itself
2366 -- or one of its ancestors (taking visibility rules into account if
2367 -- in Ada 2005 mode), or a pragma Stream_Convert applies to Btyp
2368 -- (with no visibility restriction).
2371 Gen_Body
: constant Node_Id
:= Enclosing_Generic_Body
(N
);
2373 if Present
(Gen_Body
) then
2374 In_Shared_Var_Procs
:=
2375 Is_RTE
(Corresponding_Spec
(Gen_Body
), RE_Shared_Var_Procs
);
2377 In_Shared_Var_Procs
:= False;
2381 if (Comes_From_Source
(N
)
2382 and then not (In_Shared_Var_Procs
or In_Instance
))
2383 and then not Stream_Attribute_Available
(P_Type
, Nam
)
2384 and then not Has_Rep_Pragma
(Btyp
, Name_Stream_Convert
)
2386 Error_Msg_Name_1
:= Aname
;
2388 if Is_Limited_Type
(P_Type
) then
2390 ("limited type& has no% attribute", P
, P_Type
);
2391 Explain_Limited_Type
(P_Type
, P
);
2394 ("attribute% for type& is not available", P
, P_Type
);
2398 -- Check for no stream operations allowed from No_Tagged_Streams
2400 if Is_Tagged_Type
(P_Type
)
2401 and then Present
(No_Tagged_Streams_Pragma
(P_Type
))
2403 Error_Msg_Sloc
:= Sloc
(No_Tagged_Streams_Pragma
(P_Type
));
2405 ("no stream operations for & (No_Tagged_Streams #)", N
, P_Type
);
2409 -- Check restriction violations
2411 -- First check the No_Streams restriction, which prohibits the use
2412 -- of explicit stream attributes in the source program. We do not
2413 -- prevent the occurrence of stream attributes in generated code,
2414 -- for instance those generated implicitly for dispatching purposes.
2416 if Comes_From_Source
(N
) then
2417 Check_Restriction
(No_Streams
, P
);
2420 -- AI05-0057: if restriction No_Default_Stream_Attributes is active,
2421 -- it is illegal to use a predefined elementary type stream attribute
2422 -- either by itself, or more importantly as part of the attribute
2423 -- subprogram for a composite type. However, if the broader
2424 -- restriction No_Streams is active, stream operations are not
2425 -- generated, and there is no error.
2427 if Restriction_Active
(No_Default_Stream_Attributes
)
2428 and then not Restriction_Active
(No_Streams
)
2434 if Nam
= TSS_Stream_Input
2436 Nam
= TSS_Stream_Read
2439 Type_Without_Stream_Operation
(P_Type
, TSS_Stream_Read
);
2442 Type_Without_Stream_Operation
(P_Type
, TSS_Stream_Write
);
2446 Check_Restriction
(No_Default_Stream_Attributes
, N
);
2449 ("missing user-defined Stream Read or Write for type&",
2451 if not Is_Elementary_Type
(P_Type
) then
2453 ("\which is a component of type&", N
, P_Type
);
2459 -- Check special case of Exception_Id and Exception_Occurrence which
2460 -- are not allowed for restriction No_Exception_Registration.
2462 if Restriction_Check_Required
(No_Exception_Registration
)
2463 and then (Is_RTE
(P_Type
, RE_Exception_Id
)
2465 Is_RTE
(P_Type
, RE_Exception_Occurrence
))
2467 Check_Restriction
(No_Exception_Registration
, P
);
2470 -- Here we must check that the first argument is an access type
2471 -- that is compatible with Ada.Streams.Root_Stream_Type'Class.
2473 Analyze_And_Resolve
(E1
);
2476 -- Note: the double call to Root_Type here is needed because the
2477 -- root type of a class-wide type is the corresponding type (e.g.
2478 -- X for X'Class, and we really want to go to the root.)
2480 if not Is_Access_Type
(Etyp
)
2481 or else Root_Type
(Root_Type
(Designated_Type
(Etyp
))) /=
2482 RTE
(RE_Root_Stream_Type
)
2485 ("expected access to Ada.Streams.Root_Stream_Type''Class", E1
);
2488 -- Check that the second argument is of the right type if there is
2489 -- one (the Input attribute has only one argument so this is skipped)
2491 if Present
(E2
) then
2494 if Nam
= TSS_Stream_Read
2495 and then not Is_OK_Variable_For_Out_Formal
(E2
)
2498 ("second argument of % attribute must be a variable", E2
);
2501 Resolve
(E2
, P_Type
);
2505 end Check_Stream_Attribute
;
2507 -------------------------
2508 -- Check_System_Prefix --
2509 -------------------------
2511 procedure Check_System_Prefix
is
2513 if Nkind
(P
) /= N_Identifier
or else Chars
(P
) /= Name_System
then
2514 Error_Attr
("only allowed prefix for % attribute is System", P
);
2516 end Check_System_Prefix
;
2518 -----------------------
2519 -- Check_Task_Prefix --
2520 -----------------------
2522 procedure Check_Task_Prefix
is
2526 -- Ada 2005 (AI-345): Attribute 'Terminated can be applied to
2527 -- task interface class-wide types.
2529 if Is_Task_Type
(Etype
(P
))
2530 or else (Is_Access_Type
(Etype
(P
))
2531 and then Is_Task_Type
(Designated_Type
(Etype
(P
))))
2532 or else (Ada_Version
>= Ada_2005
2533 and then Ekind
(Etype
(P
)) = E_Class_Wide_Type
2534 and then Is_Interface
(Etype
(P
))
2535 and then Is_Task_Interface
(Etype
(P
)))
2540 if Ada_Version
>= Ada_2005
then
2542 ("prefix of % attribute must be a task or a task " &
2543 "interface class-wide object");
2546 Error_Attr_P
("prefix of % attribute must be a task");
2549 end Check_Task_Prefix
;
2555 -- The possibilities are an entity name denoting a type, or an
2556 -- attribute reference that denotes a type (Base or Class). If
2557 -- the type is incomplete, replace it with its full view.
2559 procedure Check_Type
is
2561 if not Is_Entity_Name
(P
)
2562 or else not Is_Type
(Entity
(P
))
2564 Error_Attr_P
("prefix of % attribute must be a type");
2566 elsif Is_Protected_Self_Reference
(P
) then
2568 ("prefix of % attribute denotes current instance "
2569 & "(RM 9.4(21/2))");
2571 elsif Ekind
(Entity
(P
)) = E_Incomplete_Type
2572 and then Present
(Full_View
(Entity
(P
)))
2574 P_Type
:= Full_View
(Entity
(P
));
2575 Set_Entity
(P
, P_Type
);
2579 ---------------------
2580 -- Check_Unit_Name --
2581 ---------------------
2583 procedure Check_Unit_Name
(Nod
: Node_Id
) is
2585 if Nkind
(Nod
) = N_Identifier
then
2588 elsif Nkind_In
(Nod
, N_Selected_Component
, N_Expanded_Name
) then
2589 Check_Unit_Name
(Prefix
(Nod
));
2591 if Nkind
(Selector_Name
(Nod
)) = N_Identifier
then
2596 Error_Attr
("argument for % attribute must be unit name", P
);
2597 end Check_Unit_Name
;
2603 procedure Error_Attr
is
2605 Set_Etype
(N
, Any_Type
);
2606 Set_Entity
(N
, Any_Type
);
2607 raise Bad_Attribute
;
2610 procedure Error_Attr
(Msg
: String; Error_Node
: Node_Id
) is
2612 Error_Msg_Name_1
:= Aname
;
2613 Error_Msg_N
(Msg
, Error_Node
);
2621 procedure Error_Attr_P
(Msg
: String) is
2623 Error_Msg_Name_1
:= Aname
;
2624 Error_Msg_F
(Msg
, P
);
2628 ----------------------------
2629 -- Legal_Formal_Attribute --
2630 ----------------------------
2632 procedure Legal_Formal_Attribute
is
2636 if not Is_Entity_Name
(P
)
2637 or else not Is_Type
(Entity
(P
))
2639 Error_Attr_P
("prefix of % attribute must be generic type");
2641 elsif Is_Generic_Actual_Type
(Entity
(P
))
2643 or else In_Inlined_Body
2647 elsif Is_Generic_Type
(Entity
(P
)) then
2648 if Is_Definite_Subtype
(Entity
(P
)) then
2650 ("prefix of % attribute must be indefinite generic type");
2655 ("prefix of % attribute must be indefinite generic type");
2658 Set_Etype
(N
, Standard_Boolean
);
2659 end Legal_Formal_Attribute
;
2661 ---------------------------------------------------------------
2662 -- Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements --
2663 ---------------------------------------------------------------
2665 procedure Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
is
2669 Check_Not_Incomplete_Type
;
2670 Set_Etype
(N
, Universal_Integer
);
2671 end Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
;
2677 procedure Min_Max
is
2681 Resolve
(E1
, P_Base_Type
);
2682 Resolve
(E2
, P_Base_Type
);
2683 Set_Etype
(N
, P_Base_Type
);
2685 -- Check for comparison on unordered enumeration type
2687 if Bad_Unordered_Enumeration_Reference
(N
, P_Base_Type
) then
2688 Error_Msg_Sloc
:= Sloc
(P_Base_Type
);
2690 ("comparison on unordered enumeration type& declared#?U?",
2695 ------------------------
2696 -- Standard_Attribute --
2697 ------------------------
2699 procedure Standard_Attribute
(Val
: Int
) is
2701 Check_Standard_Prefix
;
2702 Rewrite
(N
, Make_Integer_Literal
(Loc
, Val
));
2704 Set_Is_Static_Expression
(N
, True);
2705 end Standard_Attribute
;
2707 --------------------
2708 -- Uneval_Old_Msg --
2709 --------------------
2711 procedure Uneval_Old_Msg
is
2712 Uneval_Old_Setting
: Character;
2716 -- If from aspect, then Uneval_Old_Setting comes from flags in the
2717 -- N_Aspect_Specification node that corresponds to the attribute.
2719 -- First find the pragma in which we appear (note that at this stage,
2720 -- even if we appeared originally within an aspect specification, we
2721 -- are now within the corresponding pragma).
2725 Prag
:= Parent
(Prag
);
2726 exit when No
(Prag
) or else Nkind
(Prag
) = N_Pragma
;
2729 if Present
(Prag
) then
2730 if Uneval_Old_Accept
(Prag
) then
2731 Uneval_Old_Setting
:= 'A';
2732 elsif Uneval_Old_Warn
(Prag
) then
2733 Uneval_Old_Setting
:= 'W';
2735 Uneval_Old_Setting
:= 'E';
2738 -- If we did not find the pragma, that's odd, just use the setting
2739 -- from Opt.Uneval_Old. Perhaps this is due to a previous error?
2742 Uneval_Old_Setting
:= Opt
.Uneval_Old
;
2745 -- Processing depends on the setting of Uneval_Old
2747 case Uneval_Old_Setting
is
2750 ("prefix of attribute % that is potentially "
2751 & "unevaluated must denote an entity");
2754 Error_Msg_Name_1
:= Aname
;
2756 ("??prefix of attribute % appears in potentially "
2757 & "unevaluated context, exception may be raised", P
);
2763 raise Program_Error
;
2767 -------------------------
2768 -- Unexpected Argument --
2769 -------------------------
2771 procedure Unexpected_Argument
(En
: Node_Id
) is
2773 Error_Attr
("unexpected argument for % attribute", En
);
2774 end Unexpected_Argument
;
2776 -------------------------------------------------
2777 -- Validate_Non_Static_Attribute_Function_Call --
2778 -------------------------------------------------
2780 -- This function should be moved to Sem_Dist ???
2782 procedure Validate_Non_Static_Attribute_Function_Call
is
2784 if In_Preelaborated_Unit
2785 and then not In_Subprogram_Or_Concurrent_Unit
2787 Flag_Non_Static_Expr
2788 ("non-static function call in preelaborated unit!", N
);
2790 end Validate_Non_Static_Attribute_Function_Call
;
2792 -- Start of processing for Analyze_Attribute
2795 -- Immediate return if unrecognized attribute (already diagnosed by
2796 -- parser, so there is nothing more that we need to do).
2798 if not Is_Attribute_Name
(Aname
) then
2799 raise Bad_Attribute
;
2802 Check_Restriction_No_Use_Of_Attribute
(N
);
2804 -- Deal with Ada 83 issues
2806 if Comes_From_Source
(N
) then
2807 if not Attribute_83
(Attr_Id
) then
2808 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
2809 Error_Msg_Name_1
:= Aname
;
2810 Error_Msg_N
("(Ada 83) attribute% is not standard??", N
);
2813 if Attribute_Impl_Def
(Attr_Id
) then
2814 Check_Restriction
(No_Implementation_Attributes
, N
);
2819 -- Deal with Ada 2005 attributes that are implementation attributes
2820 -- because they appear in a version of Ada before Ada 2005, and
2821 -- similarly for Ada 2012 attributes appearing in an earlier version.
2823 if (Attribute_05
(Attr_Id
) and then Ada_Version
< Ada_2005
)
2825 (Attribute_12
(Attr_Id
) and then Ada_Version
< Ada_2012
)
2827 Check_Restriction
(No_Implementation_Attributes
, N
);
2830 -- Remote access to subprogram type access attribute reference needs
2831 -- unanalyzed copy for tree transformation. The analyzed copy is used
2832 -- for its semantic information (whether prefix is a remote subprogram
2833 -- name), the unanalyzed copy is used to construct new subtree rooted
2834 -- with N_Aggregate which represents a fat pointer aggregate.
2836 if Aname
= Name_Access
then
2837 Discard_Node
(Copy_Separate_Tree
(N
));
2840 -- Analyze prefix and exit if error in analysis. If the prefix is an
2841 -- incomplete type, use full view if available. Note that there are
2842 -- some attributes for which we do not analyze the prefix, since the
2843 -- prefix is not a normal name, or else needs special handling.
2845 if Aname
/= Name_Elab_Body
and then
2846 Aname
/= Name_Elab_Spec
and then
2847 Aname
/= Name_Elab_Subp_Body
and then
2848 Aname
/= Name_Enabled
and then
2852 P_Type
:= Etype
(P
);
2854 if Is_Entity_Name
(P
)
2855 and then Present
(Entity
(P
))
2856 and then Is_Type
(Entity
(P
))
2858 if Ekind
(Entity
(P
)) = E_Incomplete_Type
then
2859 P_Type
:= Get_Full_View
(P_Type
);
2860 Set_Entity
(P
, P_Type
);
2861 Set_Etype
(P
, P_Type
);
2863 elsif Entity
(P
) = Current_Scope
2864 and then Is_Record_Type
(Entity
(P
))
2866 -- Use of current instance within the type. Verify that if the
2867 -- attribute appears within a constraint, it yields an access
2868 -- type, other uses are illegal.
2876 and then Nkind
(Parent
(Par
)) /= N_Component_Definition
2878 Par
:= Parent
(Par
);
2882 and then Nkind
(Par
) = N_Subtype_Indication
2884 if Attr_Id
/= Attribute_Access
2885 and then Attr_Id
/= Attribute_Unchecked_Access
2886 and then Attr_Id
/= Attribute_Unrestricted_Access
2889 ("in a constraint the current instance can only "
2890 & "be used with an access attribute", N
);
2897 if P_Type
= Any_Type
then
2898 raise Bad_Attribute
;
2901 P_Base_Type
:= Base_Type
(P_Type
);
2904 -- Analyze expressions that may be present, exiting if an error occurs
2911 E1
:= First
(Exprs
);
2913 -- Skip analysis for case of Restriction_Set, we do not expect
2914 -- the argument to be analyzed in this case.
2916 if Aname
/= Name_Restriction_Set
then
2919 -- Check for missing/bad expression (result of previous error)
2921 if No
(E1
) or else Etype
(E1
) = Any_Type
then
2922 raise Bad_Attribute
;
2928 if Present
(E2
) then
2931 if Etype
(E2
) = Any_Type
then
2932 raise Bad_Attribute
;
2935 if Present
(Next
(E2
)) then
2936 Unexpected_Argument
(Next
(E2
));
2941 -- Cases where prefix must be resolvable by itself
2943 if Is_Overloaded
(P
)
2944 and then Aname
/= Name_Access
2945 and then Aname
/= Name_Address
2946 and then Aname
/= Name_Code_Address
2947 and then Aname
/= Name_Result
2948 and then Aname
/= Name_Unchecked_Access
2950 -- The prefix must be resolvable by itself, without reference to the
2951 -- attribute. One case that requires special handling is a prefix
2952 -- that is a function name, where one interpretation may be a
2953 -- parameterless call. Entry attributes are handled specially below.
2955 if Is_Entity_Name
(P
)
2956 and then not Nam_In
(Aname
, Name_Count
, Name_Caller
)
2958 Check_Parameterless_Call
(P
);
2961 if Is_Overloaded
(P
) then
2963 -- Ada 2005 (AI-345): Since protected and task types have
2964 -- primitive entry wrappers, the attributes Count, and Caller
2965 -- require a context check
2967 if Nam_In
(Aname
, Name_Count
, Name_Caller
) then
2969 Count
: Natural := 0;
2974 Get_First_Interp
(P
, I
, It
);
2975 while Present
(It
.Nam
) loop
2976 if Comes_From_Source
(It
.Nam
) then
2982 Get_Next_Interp
(I
, It
);
2986 Error_Attr
("ambiguous prefix for % attribute", P
);
2988 Set_Is_Overloaded
(P
, False);
2993 Error_Attr
("ambiguous prefix for % attribute", P
);
2998 -- In SPARK, attributes of private types are only allowed if the full
2999 -- type declaration is visible.
3001 -- Note: the check for Present (Entity (P)) defends against some error
3002 -- conditions where the Entity field is not set.
3004 if Is_Entity_Name
(P
) and then Present
(Entity
(P
))
3005 and then Is_Type
(Entity
(P
))
3006 and then Is_Private_Type
(P_Type
)
3007 and then not In_Open_Scopes
(Scope
(P_Type
))
3008 and then not In_Spec_Expression
3010 Check_SPARK_05_Restriction
("invisible attribute of type", N
);
3013 -- Remaining processing depends on attribute
3017 -- Attributes related to Ada 2012 iterators. Attribute specifications
3018 -- exist for these, but they cannot be queried.
3020 when Attribute_Constant_Indexing
3021 | Attribute_Default_Iterator
3022 | Attribute_Implicit_Dereference
3023 | Attribute_Iterator_Element
3024 | Attribute_Iterable
3025 | Attribute_Variable_Indexing
3027 Error_Msg_N
("illegal attribute", N
);
3029 -- Internal attributes used to deal with Ada 2012 delayed aspects. These
3030 -- were already rejected by the parser. Thus they shouldn't appear here.
3032 when Internal_Attribute_Id
=>
3033 raise Program_Error
;
3039 when Attribute_Abort_Signal
=>
3040 Check_Standard_Prefix
;
3041 Rewrite
(N
, New_Occurrence_Of
(Stand
.Abort_Signal
, Loc
));
3048 when Attribute_Access
=>
3049 Analyze_Access_Attribute
;
3050 Check_Not_Incomplete_Type
;
3056 when Attribute_Address
=>
3059 Check_Not_Incomplete_Type
;
3060 Set_Etype
(N
, RTE
(RE_Address
));
3066 when Attribute_Address_Size
=>
3067 Standard_Attribute
(System_Address_Size
);
3073 when Attribute_Adjacent
=>
3074 Check_Floating_Point_Type_2
;
3075 Set_Etype
(N
, P_Base_Type
);
3076 Resolve
(E1
, P_Base_Type
);
3077 Resolve
(E2
, P_Base_Type
);
3083 when Attribute_Aft
=>
3084 Check_Fixed_Point_Type_0
;
3085 Set_Etype
(N
, Universal_Integer
);
3091 when Attribute_Alignment
=>
3093 -- Don't we need more checking here, cf Size ???
3096 Check_Not_Incomplete_Type
;
3098 Set_Etype
(N
, Universal_Integer
);
3104 when Attribute_Asm_Input
=>
3105 Check_Asm_Attribute
;
3107 -- The back end may need to take the address of E2
3109 if Is_Entity_Name
(E2
) then
3110 Set_Address_Taken
(Entity
(E2
));
3113 Set_Etype
(N
, RTE
(RE_Asm_Input_Operand
));
3119 when Attribute_Asm_Output
=>
3120 Check_Asm_Attribute
;
3122 if Etype
(E2
) = Any_Type
then
3125 elsif Aname
= Name_Asm_Output
then
3126 if not Is_Variable
(E2
) then
3128 ("second argument for Asm_Output is not variable", E2
);
3132 Note_Possible_Modification
(E2
, Sure
=> True);
3134 -- The back end may need to take the address of E2
3136 if Is_Entity_Name
(E2
) then
3137 Set_Address_Taken
(Entity
(E2
));
3140 Set_Etype
(N
, RTE
(RE_Asm_Output_Operand
));
3142 -----------------------------
3143 -- Atomic_Always_Lock_Free --
3144 -----------------------------
3146 when Attribute_Atomic_Always_Lock_Free
=>
3149 Set_Etype
(N
, Standard_Boolean
);
3155 -- Note: when the base attribute appears in the context of a subtype
3156 -- mark, the analysis is done by Sem_Ch8.Find_Type, rather than by
3157 -- the following circuit.
3159 when Attribute_Base
=> Base
: declare
3167 if Ada_Version
>= Ada_95
3168 and then not Is_Scalar_Type
(Typ
)
3169 and then not Is_Generic_Type
(Typ
)
3171 Error_Attr_P
("prefix of Base attribute must be scalar type");
3173 elsif Sloc
(Typ
) = Standard_Location
3174 and then Base_Type
(Typ
) = Typ
3175 and then Warn_On_Redundant_Constructs
3177 Error_Msg_NE
-- CODEFIX
3178 ("?r?redundant attribute, & is its own base type", N
, Typ
);
3181 if Nkind
(Parent
(N
)) /= N_Attribute_Reference
then
3182 Error_Msg_Name_1
:= Aname
;
3183 Check_SPARK_05_Restriction
3184 ("attribute% is only allowed as prefix of another attribute", P
);
3187 Set_Etype
(N
, Base_Type
(Entity
(P
)));
3188 Set_Entity
(N
, Base_Type
(Entity
(P
)));
3189 Rewrite
(N
, New_Occurrence_Of
(Entity
(N
), Loc
));
3197 when Attribute_Bit
=>
3200 if not Is_Object_Reference
(P
) then
3201 Error_Attr_P
("prefix for % attribute must be object");
3203 -- What about the access object cases ???
3209 Set_Etype
(N
, Universal_Integer
);
3215 when Attribute_Bit_Order
=>
3219 if not Is_Record_Type
(P_Type
) then
3220 Error_Attr_P
("prefix of % attribute must be record type");
3223 if Bytes_Big_Endian
xor Reverse_Bit_Order
(P_Type
) then
3225 New_Occurrence_Of
(RTE
(RE_High_Order_First
), Loc
));
3228 New_Occurrence_Of
(RTE
(RE_Low_Order_First
), Loc
));
3231 Set_Etype
(N
, RTE
(RE_Bit_Order
));
3234 -- Reset incorrect indication of staticness
3236 Set_Is_Static_Expression
(N
, False);
3242 -- Note: in generated code, we can have a Bit_Position attribute
3243 -- applied to a (naked) record component (i.e. the prefix is an
3244 -- identifier that references an E_Component or E_Discriminant
3245 -- entity directly, and this is interpreted as expected by Gigi.
3246 -- The following code will not tolerate such usage, but when the
3247 -- expander creates this special case, it marks it as analyzed
3248 -- immediately and sets an appropriate type.
3250 when Attribute_Bit_Position
=>
3251 if Comes_From_Source
(N
) then
3255 Set_Etype
(N
, Universal_Integer
);
3261 when Attribute_Body_Version
=>
3264 Set_Etype
(N
, RTE
(RE_Version_String
));
3270 when Attribute_Callable
=>
3272 Set_Etype
(N
, Standard_Boolean
);
3279 when Attribute_Caller
=> Caller
: declare
3286 if Nkind_In
(P
, N_Identifier
, N_Expanded_Name
) then
3289 if not Is_Entry
(Ent
) then
3290 Error_Attr
("invalid entry name", N
);
3294 Error_Attr
("invalid entry name", N
);
3298 for J
in reverse 0 .. Scope_Stack
.Last
loop
3299 S
:= Scope_Stack
.Table
(J
).Entity
;
3301 if S
= Scope
(Ent
) then
3302 Error_Attr
("Caller must appear in matching accept or body", N
);
3308 Set_Etype
(N
, RTE
(RO_AT_Task_Id
));
3315 when Attribute_Ceiling
=>
3316 Check_Floating_Point_Type_1
;
3317 Set_Etype
(N
, P_Base_Type
);
3318 Resolve
(E1
, P_Base_Type
);
3324 when Attribute_Class
=>
3325 Check_Restriction
(No_Dispatch
, N
);
3329 -- Applying Class to untagged incomplete type is obsolescent in Ada
3330 -- 2005. Note that we can't test Is_Tagged_Type here on P_Type, since
3331 -- this flag gets set by Find_Type in this situation.
3333 if Restriction_Check_Required
(No_Obsolescent_Features
)
3334 and then Ada_Version
>= Ada_2005
3335 and then Ekind
(P_Type
) = E_Incomplete_Type
3338 DN
: constant Node_Id
:= Declaration_Node
(P_Type
);
3340 if Nkind
(DN
) = N_Incomplete_Type_Declaration
3341 and then not Tagged_Present
(DN
)
3343 Check_Restriction
(No_Obsolescent_Features
, P
);
3352 when Attribute_Code_Address
=>
3355 if Nkind
(P
) = N_Attribute_Reference
3356 and then Nam_In
(Attribute_Name
(P
), Name_Elab_Body
, Name_Elab_Spec
)
3360 elsif not Is_Entity_Name
(P
)
3361 or else (Ekind
(Entity
(P
)) /= E_Function
3363 Ekind
(Entity
(P
)) /= E_Procedure
)
3365 Error_Attr
("invalid prefix for % attribute", P
);
3366 Set_Address_Taken
(Entity
(P
));
3368 -- Issue an error if the prefix denotes an eliminated subprogram
3371 Check_For_Eliminated_Subprogram
(P
, Entity
(P
));
3374 Set_Etype
(N
, RTE
(RE_Address
));
3376 ----------------------
3377 -- Compiler_Version --
3378 ----------------------
3380 when Attribute_Compiler_Version
=>
3382 Check_Standard_Prefix
;
3383 Rewrite
(N
, Make_String_Literal
(Loc
, "GNAT " & Gnat_Version_String
));
3384 Analyze_And_Resolve
(N
, Standard_String
);
3385 Set_Is_Static_Expression
(N
, True);
3387 --------------------
3388 -- Component_Size --
3389 --------------------
3391 when Attribute_Component_Size
=>
3393 Set_Etype
(N
, Universal_Integer
);
3395 -- Note: unlike other array attributes, unconstrained arrays are OK
3397 if Is_Array_Type
(P_Type
) and then not Is_Constrained
(P_Type
) then
3407 when Attribute_Compose
=>
3408 Check_Floating_Point_Type_2
;
3409 Set_Etype
(N
, P_Base_Type
);
3410 Resolve
(E1
, P_Base_Type
);
3411 Resolve
(E2
, Any_Integer
);
3417 when Attribute_Constrained
=>
3419 Set_Etype
(N
, Standard_Boolean
);
3421 -- Case from RM J.4(2) of constrained applied to private type
3423 if Is_Entity_Name
(P
) and then Is_Type
(Entity
(P
)) then
3424 Check_Restriction
(No_Obsolescent_Features
, P
);
3426 if Warn_On_Obsolescent_Feature
then
3428 ("constrained for private type is an obsolescent feature "
3429 & "(RM J.4)?j?", N
);
3432 -- If we are within an instance, the attribute must be legal
3433 -- because it was valid in the generic unit. Ditto if this is
3434 -- an inlining of a function declared in an instance.
3436 if In_Instance
or else In_Inlined_Body
then
3439 -- For sure OK if we have a real private type itself, but must
3440 -- be completed, cannot apply Constrained to incomplete type.
3442 elsif Is_Private_Type
(Entity
(P
)) then
3444 -- Note: this is one of the Annex J features that does not
3445 -- generate a warning from -gnatwj, since in fact it seems
3446 -- very useful, and is used in the GNAT runtime.
3448 Check_Not_Incomplete_Type
;
3452 -- Normal (non-obsolescent case) of application to object of
3453 -- a discriminated type.
3456 Check_Object_Reference
(P
);
3458 -- If N does not come from source, then we allow the
3459 -- the attribute prefix to be of a private type whose
3460 -- full type has discriminants. This occurs in cases
3461 -- involving expanded calls to stream attributes.
3463 if not Comes_From_Source
(N
) then
3464 P_Type
:= Underlying_Type
(P_Type
);
3467 -- Must have discriminants or be an access type designating a type
3468 -- with discriminants. If it is a class-wide type it has unknown
3471 if Has_Discriminants
(P_Type
)
3472 or else Has_Unknown_Discriminants
(P_Type
)
3474 (Is_Access_Type
(P_Type
)
3475 and then Has_Discriminants
(Designated_Type
(P_Type
)))
3479 -- The rule given in 3.7.2 is part of static semantics, but the
3480 -- intent is clearly that it be treated as a legality rule, and
3481 -- rechecked in the visible part of an instance. Nevertheless
3482 -- the intent also seems to be it should legally apply to the
3483 -- actual of a formal with unknown discriminants, regardless of
3484 -- whether the actual has discriminants, in which case the value
3485 -- of the attribute is determined using the J.4 rules. This choice
3486 -- seems the most useful, and is compatible with existing tests.
3488 elsif In_Instance
then
3491 -- Also allow an object of a generic type if extensions allowed
3492 -- and allow this for any type at all. (this may be obsolete ???)
3494 elsif (Is_Generic_Type
(P_Type
)
3495 or else Is_Generic_Actual_Type
(P_Type
))
3496 and then Extensions_Allowed
3502 -- Fall through if bad prefix
3505 ("prefix of % attribute must be object of discriminated type");
3511 when Attribute_Copy_Sign
=>
3512 Check_Floating_Point_Type_2
;
3513 Set_Etype
(N
, P_Base_Type
);
3514 Resolve
(E1
, P_Base_Type
);
3515 Resolve
(E2
, P_Base_Type
);
3521 when Attribute_Count
=> Count
: declare
3529 if Nkind_In
(P
, N_Identifier
, N_Expanded_Name
) then
3532 if Ekind
(Ent
) /= E_Entry
then
3533 Error_Attr
("invalid entry name", N
);
3536 elsif Nkind
(P
) = N_Indexed_Component
then
3537 if not Is_Entity_Name
(Prefix
(P
))
3538 or else No
(Entity
(Prefix
(P
)))
3539 or else Ekind
(Entity
(Prefix
(P
))) /= E_Entry_Family
3541 if Nkind
(Prefix
(P
)) = N_Selected_Component
3542 and then Present
(Entity
(Selector_Name
(Prefix
(P
))))
3543 and then Ekind
(Entity
(Selector_Name
(Prefix
(P
)))) =
3547 ("attribute % must apply to entry of current task", P
);
3550 Error_Attr
("invalid entry family name", P
);
3555 Ent
:= Entity
(Prefix
(P
));
3558 elsif Nkind
(P
) = N_Selected_Component
3559 and then Present
(Entity
(Selector_Name
(P
)))
3560 and then Ekind
(Entity
(Selector_Name
(P
))) = E_Entry
3563 ("attribute % must apply to entry of current task", P
);
3566 Error_Attr
("invalid entry name", N
);
3570 for J
in reverse 0 .. Scope_Stack
.Last
loop
3571 S
:= Scope_Stack
.Table
(J
).Entity
;
3573 if S
= Scope
(Ent
) then
3574 if Nkind
(P
) = N_Expanded_Name
then
3575 Tsk
:= Entity
(Prefix
(P
));
3577 -- The prefix denotes either the task type, or else a
3578 -- single task whose task type is being analyzed.
3580 if (Is_Type
(Tsk
) and then Tsk
= S
)
3581 or else (not Is_Type
(Tsk
)
3582 and then Etype
(Tsk
) = S
3583 and then not (Comes_From_Source
(S
)))
3588 ("Attribute % must apply to entry of current task", N
);
3594 elsif Ekind
(Scope
(Ent
)) in Task_Kind
3595 and then not Ekind_In
(S
, E_Block
,
3600 Error_Attr
("Attribute % cannot appear in inner unit", N
);
3602 elsif Ekind
(Scope
(Ent
)) = E_Protected_Type
3603 and then not Has_Completion
(Scope
(Ent
))
3605 Error_Attr
("attribute % can only be used inside body", N
);
3609 if Is_Overloaded
(P
) then
3611 Index
: Interp_Index
;
3615 Get_First_Interp
(P
, Index
, It
);
3616 while Present
(It
.Nam
) loop
3617 if It
.Nam
= Ent
then
3620 -- Ada 2005 (AI-345): Do not consider primitive entry
3621 -- wrappers generated for task or protected types.
3623 elsif Ada_Version
>= Ada_2005
3624 and then not Comes_From_Source
(It
.Nam
)
3629 Error_Attr
("ambiguous entry name", N
);
3632 Get_Next_Interp
(Index
, It
);
3637 Set_Etype
(N
, Universal_Integer
);
3640 -----------------------
3641 -- Default_Bit_Order --
3642 -----------------------
3644 when Attribute_Default_Bit_Order
=> Default_Bit_Order
: declare
3645 Target_Default_Bit_Order
: System
.Bit_Order
;
3648 Check_Standard_Prefix
;
3650 if Bytes_Big_Endian
then
3651 Target_Default_Bit_Order
:= System
.High_Order_First
;
3653 Target_Default_Bit_Order
:= System
.Low_Order_First
;
3657 Make_Integer_Literal
(Loc
,
3658 UI_From_Int
(System
.Bit_Order
'Pos (Target_Default_Bit_Order
))));
3660 Set_Etype
(N
, Universal_Integer
);
3661 Set_Is_Static_Expression
(N
);
3662 end Default_Bit_Order
;
3664 ----------------------------------
3665 -- Default_Scalar_Storage_Order --
3666 ----------------------------------
3668 when Attribute_Default_Scalar_Storage_Order
=> Default_SSO
: declare
3669 RE_Default_SSO
: RE_Id
;
3672 Check_Standard_Prefix
;
3674 case Opt
.Default_SSO
is
3676 if Bytes_Big_Endian
then
3677 RE_Default_SSO
:= RE_High_Order_First
;
3679 RE_Default_SSO
:= RE_Low_Order_First
;
3683 RE_Default_SSO
:= RE_High_Order_First
;
3686 RE_Default_SSO
:= RE_Low_Order_First
;
3689 raise Program_Error
;
3692 Rewrite
(N
, New_Occurrence_Of
(RTE
(RE_Default_SSO
), Loc
));
3699 when Attribute_Definite
=>
3700 Legal_Formal_Attribute
;
3706 when Attribute_Delta
=>
3707 Check_Fixed_Point_Type_0
;
3708 Set_Etype
(N
, Universal_Real
);
3714 when Attribute_Denorm
=>
3715 Check_Floating_Point_Type_0
;
3716 Set_Etype
(N
, Standard_Boolean
);
3722 when Attribute_Deref
=>
3725 Resolve
(E1
, RTE
(RE_Address
));
3726 Set_Etype
(N
, P_Type
);
3728 ---------------------
3729 -- Descriptor_Size --
3730 ---------------------
3732 when Attribute_Descriptor_Size
=>
3735 if not Is_Entity_Name
(P
) or else not Is_Type
(Entity
(P
)) then
3736 Error_Attr_P
("prefix of attribute % must denote a type");
3739 Set_Etype
(N
, Universal_Integer
);
3745 when Attribute_Digits
=>
3749 if not Is_Floating_Point_Type
(P_Type
)
3750 and then not Is_Decimal_Fixed_Point_Type
(P_Type
)
3753 ("prefix of % attribute must be float or decimal type");
3756 Set_Etype
(N
, Universal_Integer
);
3762 -- Also handles processing for Elab_Spec and Elab_Subp_Body
3764 when Attribute_Elab_Body
3765 | Attribute_Elab_Spec
3766 | Attribute_Elab_Subp_Body
3769 Check_Unit_Name
(P
);
3770 Set_Etype
(N
, Standard_Void_Type
);
3772 -- We have to manually call the expander in this case to get
3773 -- the necessary expansion (normally attributes that return
3774 -- entities are not expanded).
3782 -- Shares processing with Elab_Body
3788 when Attribute_Elaborated
=>
3790 Check_Unit_Name
(P
);
3791 Set_Etype
(N
, Standard_Boolean
);
3797 when Attribute_Emax
=>
3798 Check_Floating_Point_Type_0
;
3799 Set_Etype
(N
, Universal_Integer
);
3805 when Attribute_Enabled
=>
3806 Check_Either_E0_Or_E1
;
3808 if Present
(E1
) then
3809 if not Is_Entity_Name
(E1
) or else No
(Entity
(E1
)) then
3810 Error_Msg_N
("entity name expected for Enabled attribute", E1
);
3815 if Nkind
(P
) /= N_Identifier
then
3816 Error_Msg_N
("identifier expected (check name)", P
);
3817 elsif Get_Check_Id
(Chars
(P
)) = No_Check_Id
then
3818 Error_Msg_N
("& is not a recognized check name", P
);
3821 Set_Etype
(N
, Standard_Boolean
);
3827 when Attribute_Enum_Rep
=>
3829 -- T'Enum_Rep (X) case
3831 if Present
(E1
) then
3833 Check_Discrete_Type
;
3834 Resolve
(E1
, P_Base_Type
);
3836 -- X'Enum_Rep case. X must be an object or enumeration literal, and
3837 -- it must be of a discrete type.
3840 ((Is_Object_Reference
(P
)
3843 and then Ekind
(Entity
(P
)) = E_Enumeration_Literal
))
3844 and then Is_Discrete_Type
(Etype
(P
)))
3846 Error_Attr_P
("prefix of % attribute must be discrete object");
3849 Set_Etype
(N
, Universal_Integer
);
3855 when Attribute_Enum_Val
=>
3859 if not Is_Enumeration_Type
(P_Type
) then
3860 Error_Attr_P
("prefix of % attribute must be enumeration type");
3863 -- If the enumeration type has a standard representation, the effect
3864 -- is the same as 'Val, so rewrite the attribute as a 'Val.
3866 if not Has_Non_Standard_Rep
(P_Base_Type
) then
3868 Make_Attribute_Reference
(Loc
,
3869 Prefix
=> Relocate_Node
(Prefix
(N
)),
3870 Attribute_Name
=> Name_Val
,
3871 Expressions
=> New_List
(Relocate_Node
(E1
))));
3872 Analyze_And_Resolve
(N
, P_Base_Type
);
3874 -- Non-standard representation case (enumeration with holes)
3878 Resolve
(E1
, Any_Integer
);
3879 Set_Etype
(N
, P_Base_Type
);
3886 when Attribute_Epsilon
=>
3887 Check_Floating_Point_Type_0
;
3888 Set_Etype
(N
, Universal_Real
);
3894 when Attribute_Exponent
=>
3895 Check_Floating_Point_Type_1
;
3896 Set_Etype
(N
, Universal_Integer
);
3897 Resolve
(E1
, P_Base_Type
);
3903 when Attribute_External_Tag
=>
3907 Set_Etype
(N
, Standard_String
);
3909 if not Is_Tagged_Type
(P_Type
) then
3910 Error_Attr_P
("prefix of % attribute must be tagged");
3917 when Attribute_Fast_Math
=>
3918 Check_Standard_Prefix
;
3919 Rewrite
(N
, New_Occurrence_Of
(Boolean_Literals
(Fast_Math
), Loc
));
3921 -----------------------
3922 -- Finalization_Size --
3923 -----------------------
3925 when Attribute_Finalization_Size
=>
3928 -- The prefix denotes an object
3930 if Is_Object_Reference
(P
) then
3931 Check_Object_Reference
(P
);
3933 -- The prefix denotes a type
3935 elsif Is_Entity_Name
(P
) and then Is_Type
(Entity
(P
)) then
3937 Check_Not_Incomplete_Type
;
3939 -- Attribute 'Finalization_Size is not defined for class-wide
3940 -- types because it is not possible to know statically whether
3941 -- a definite type will have controlled components or not.
3943 if Is_Class_Wide_Type
(Etype
(P
)) then
3945 ("prefix of % attribute cannot denote a class-wide type");
3948 -- The prefix denotes an illegal construct
3952 ("prefix of % attribute must be a definite type or an object");
3955 Set_Etype
(N
, Universal_Integer
);
3961 when Attribute_First
=>
3962 Check_Array_Or_Scalar_Type
;
3963 Bad_Attribute_For_Predicate
;
3969 when Attribute_First_Bit
=>
3971 Set_Etype
(N
, Universal_Integer
);
3977 when Attribute_First_Valid
=>
3978 Check_First_Last_Valid
;
3979 Set_Etype
(N
, P_Type
);
3985 when Attribute_Fixed_Value
=>
3987 Check_Fixed_Point_Type
;
3988 Resolve
(E1
, Any_Integer
);
3989 Set_Etype
(N
, P_Base_Type
);
3995 when Attribute_Floor
=>
3996 Check_Floating_Point_Type_1
;
3997 Set_Etype
(N
, P_Base_Type
);
3998 Resolve
(E1
, P_Base_Type
);
4004 when Attribute_Fore
=>
4005 Check_Fixed_Point_Type_0
;
4006 Set_Etype
(N
, Universal_Integer
);
4012 when Attribute_Fraction
=>
4013 Check_Floating_Point_Type_1
;
4014 Set_Etype
(N
, P_Base_Type
);
4015 Resolve
(E1
, P_Base_Type
);
4021 when Attribute_From_Any
=>
4023 Check_PolyORB_Attribute
;
4024 Set_Etype
(N
, P_Base_Type
);
4026 -----------------------
4027 -- Has_Access_Values --
4028 -----------------------
4030 when Attribute_Has_Access_Values
=>
4033 Set_Etype
(N
, Standard_Boolean
);
4035 ----------------------
4036 -- Has_Same_Storage --
4037 ----------------------
4039 when Attribute_Has_Same_Storage
=>
4042 -- The arguments must be objects of any type
4044 Analyze_And_Resolve
(P
);
4045 Analyze_And_Resolve
(E1
);
4046 Check_Object_Reference
(P
);
4047 Check_Object_Reference
(E1
);
4048 Set_Etype
(N
, Standard_Boolean
);
4050 -----------------------
4051 -- Has_Tagged_Values --
4052 -----------------------
4054 when Attribute_Has_Tagged_Values
=>
4057 Set_Etype
(N
, Standard_Boolean
);
4059 -----------------------
4060 -- Has_Discriminants --
4061 -----------------------
4063 when Attribute_Has_Discriminants
=>
4064 Legal_Formal_Attribute
;
4070 when Attribute_Identity
=>
4074 if Etype
(P
) = Standard_Exception_Type
then
4075 Set_Etype
(N
, RTE
(RE_Exception_Id
));
4077 -- Ada 2005 (AI-345): Attribute 'Identity may be applied to task
4078 -- interface class-wide types.
4080 elsif Is_Task_Type
(Etype
(P
))
4081 or else (Is_Access_Type
(Etype
(P
))
4082 and then Is_Task_Type
(Designated_Type
(Etype
(P
))))
4083 or else (Ada_Version
>= Ada_2005
4084 and then Ekind
(Etype
(P
)) = E_Class_Wide_Type
4085 and then Is_Interface
(Etype
(P
))
4086 and then Is_Task_Interface
(Etype
(P
)))
4089 Set_Etype
(N
, RTE
(RO_AT_Task_Id
));
4092 if Ada_Version
>= Ada_2005
then
4094 ("prefix of % attribute must be an exception, a task or a "
4095 & "task interface class-wide object");
4098 ("prefix of % attribute must be a task or an exception");
4106 when Attribute_Image
=>
4107 if Is_Real_Type
(P_Type
) then
4108 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
4109 Error_Msg_Name_1
:= Aname
;
4111 ("(Ada 83) % attribute not allowed for real types", N
);
4115 Analyze_Image_Attribute
(Standard_String
);
4121 when Attribute_Img
=>
4122 Analyze_Image_Attribute
(Standard_String
);
4128 when Attribute_Input
=>
4130 Check_Stream_Attribute
(TSS_Stream_Input
);
4131 Set_Etype
(N
, P_Base_Type
);
4137 when Attribute_Integer_Value
=>
4140 Resolve
(E1
, Any_Fixed
);
4142 -- Signal an error if argument type is not a specific fixed-point
4143 -- subtype. An error has been signalled already if the argument
4144 -- was not of a fixed-point type.
4146 if Etype
(E1
) = Any_Fixed
and then not Error_Posted
(E1
) then
4147 Error_Attr
("argument of % must be of a fixed-point type", E1
);
4150 Set_Etype
(N
, P_Base_Type
);
4156 when Attribute_Invalid_Value
=>
4159 Set_Etype
(N
, P_Base_Type
);
4160 Invalid_Value_Used
:= True;
4166 when Attribute_Large
=>
4169 Set_Etype
(N
, Universal_Real
);
4175 when Attribute_Last
=>
4176 Check_Array_Or_Scalar_Type
;
4177 Bad_Attribute_For_Predicate
;
4183 when Attribute_Last_Bit
=>
4185 Set_Etype
(N
, Universal_Integer
);
4191 when Attribute_Last_Valid
=>
4192 Check_First_Last_Valid
;
4193 Set_Etype
(N
, P_Type
);
4199 when Attribute_Leading_Part
=>
4200 Check_Floating_Point_Type_2
;
4201 Set_Etype
(N
, P_Base_Type
);
4202 Resolve
(E1
, P_Base_Type
);
4203 Resolve
(E2
, Any_Integer
);
4209 when Attribute_Length
=>
4211 Set_Etype
(N
, Universal_Integer
);
4217 when Attribute_Library_Level
=>
4220 if not Is_Entity_Name
(P
) then
4221 Error_Attr_P
("prefix of % attribute must be an entity name");
4224 if not Inside_A_Generic
then
4225 Set_Boolean_Result
(N
,
4226 Is_Library_Level_Entity
(Entity
(P
)));
4229 Set_Etype
(N
, Standard_Boolean
);
4235 when Attribute_Lock_Free
=>
4237 Set_Etype
(N
, Standard_Boolean
);
4239 if not Is_Protected_Type
(P_Type
) then
4241 ("prefix of % attribute must be a protected object");
4248 when Attribute_Loop_Entry
=> Loop_Entry
: declare
4249 procedure Check_References_In_Prefix
(Loop_Id
: Entity_Id
);
4250 -- Inspect the prefix for any uses of entities declared within the
4251 -- related loop. Loop_Id denotes the loop identifier.
4253 --------------------------------
4254 -- Check_References_In_Prefix --
4255 --------------------------------
4257 procedure Check_References_In_Prefix
(Loop_Id
: Entity_Id
) is
4258 Loop_Decl
: constant Node_Id
:= Label_Construct
(Parent
(Loop_Id
));
4260 function Check_Reference
(Nod
: Node_Id
) return Traverse_Result
;
4261 -- Determine whether a reference mentions an entity declared
4262 -- within the related loop.
4264 function Declared_Within
(Nod
: Node_Id
) return Boolean;
4265 -- Determine whether Nod appears in the subtree of Loop_Decl
4267 ---------------------
4268 -- Check_Reference --
4269 ---------------------
4271 function Check_Reference
(Nod
: Node_Id
) return Traverse_Result
is
4273 if Nkind
(Nod
) = N_Identifier
4274 and then Present
(Entity
(Nod
))
4275 and then Declared_Within
(Declaration_Node
(Entity
(Nod
)))
4278 ("prefix of attribute % cannot reference local entities",
4284 end Check_Reference
;
4286 procedure Check_References
is new Traverse_Proc
(Check_Reference
);
4288 ---------------------
4289 -- Declared_Within --
4290 ---------------------
4292 function Declared_Within
(Nod
: Node_Id
) return Boolean is
4297 while Present
(Stmt
) loop
4298 if Stmt
= Loop_Decl
then
4301 -- Prevent the search from going too far
4303 elsif Is_Body_Or_Package_Declaration
(Stmt
) then
4307 Stmt
:= Parent
(Stmt
);
4311 end Declared_Within
;
4313 -- Start of processing for Check_Prefix_For_Local_References
4316 Check_References
(P
);
4317 end Check_References_In_Prefix
;
4321 Context
: constant Node_Id
:= Parent
(N
);
4323 Encl_Loop
: Node_Id
:= Empty
;
4324 Encl_Prag
: Node_Id
:= Empty
;
4325 Loop_Id
: Entity_Id
:= Empty
;
4329 -- Start of processing for Loop_Entry
4334 -- Set the type of the attribute now to ensure the successful
4335 -- continuation of analysis even if the attribute is misplaced.
4337 Set_Etype
(Attr
, P_Type
);
4339 -- Attribute 'Loop_Entry may appear in several flavors:
4341 -- * Prefix'Loop_Entry - in this form, the attribute applies to the
4342 -- nearest enclosing loop.
4344 -- * Prefix'Loop_Entry (Expr) - depending on what Expr denotes, the
4345 -- attribute may be related to a loop denoted by label Expr or
4346 -- the prefix may denote an array object and Expr may act as an
4347 -- indexed component.
4349 -- * Prefix'Loop_Entry (Expr1, ..., ExprN) - the attribute applies
4350 -- to the nearest enclosing loop, all expressions are part of
4351 -- an indexed component.
4353 -- * Prefix'Loop_Entry (Expr) (...) (...) - depending on what Expr
4354 -- denotes, the attribute may be related to a loop denoted by
4355 -- label Expr or the prefix may denote a multidimensional array
4356 -- array object and Expr along with the rest of the expressions
4357 -- may act as indexed components.
4359 -- Regardless of variations, the attribute reference does not have an
4360 -- expression list. Instead, all available expressions are stored as
4361 -- indexed components.
4363 -- When the attribute is part of an indexed component, find the first
4364 -- expression as it will determine the semantics of 'Loop_Entry.
4366 -- If the attribute is itself an index in an indexed component, i.e.
4367 -- a member of a list, the context itself is not relevant (the code
4368 -- below would lead to an infinite loop) and the attribute applies
4369 -- to the enclosing loop.
4371 if Nkind
(Context
) = N_Indexed_Component
4372 and then not Is_List_Member
(N
)
4374 E1
:= First
(Expressions
(Context
));
4377 -- The attribute reference appears in the following form:
4379 -- Prefix'Loop_Entry (Exp1, Expr2, ..., ExprN) [(...)]
4381 -- In this case, the loop name is omitted and no rewriting is
4384 if Present
(E2
) then
4387 -- The form of the attribute is:
4389 -- Prefix'Loop_Entry (Expr) [(...)]
4391 -- If Expr denotes a loop entry, the whole attribute and indexed
4392 -- component will have to be rewritten to reflect this relation.
4395 pragma Assert
(Present
(E1
));
4397 -- Do not expand the expression as it may have side effects.
4398 -- Simply preanalyze to determine whether it is a loop name or
4401 Preanalyze_And_Resolve
(E1
);
4403 if Is_Entity_Name
(E1
)
4404 and then Present
(Entity
(E1
))
4405 and then Ekind
(Entity
(E1
)) = E_Loop
4407 Loop_Id
:= Entity
(E1
);
4409 -- Transform the attribute and enclosing indexed component
4411 Set_Expressions
(N
, Expressions
(Context
));
4412 Rewrite
(Context
, N
);
4413 Set_Etype
(Context
, P_Type
);
4420 -- The prefix must denote an object
4422 if not Is_Object_Reference
(P
) then
4423 Error_Attr_P
("prefix of attribute % must denote an object");
4426 -- The prefix cannot be of a limited type because the expansion of
4427 -- Loop_Entry must create a constant initialized by the evaluated
4430 if Is_Limited_View
(Etype
(P
)) then
4431 Error_Attr_P
("prefix of attribute % cannot be limited");
4434 -- Climb the parent chain to verify the location of the attribute and
4435 -- find the enclosing loop.
4438 while Present
(Stmt
) loop
4440 -- Locate the corresponding enclosing pragma. Note that in the
4441 -- case of Assert[And_Cut] and Assume, we have already checked
4442 -- that the pragma appears in an appropriate loop location.
4444 if Nkind
(Original_Node
(Stmt
)) = N_Pragma
4445 and then Nam_In
(Pragma_Name_Unmapped
(Original_Node
(Stmt
)),
4446 Name_Loop_Invariant
,
4449 Name_Assert_And_Cut
,
4452 Encl_Prag
:= Original_Node
(Stmt
);
4454 -- Locate the enclosing loop (if any). Note that Ada 2012 array
4455 -- iteration may be expanded into several nested loops, we are
4456 -- interested in the outermost one which has the loop identifier,
4457 -- and comes from source.
4459 elsif Nkind
(Stmt
) = N_Loop_Statement
4460 and then Present
(Identifier
(Stmt
))
4461 and then Comes_From_Source
(Original_Node
(Stmt
))
4462 and then Nkind
(Original_Node
(Stmt
)) = N_Loop_Statement
4466 -- The original attribute reference may lack a loop name. Use
4467 -- the name of the enclosing loop because it is the related
4470 if No
(Loop_Id
) then
4471 Loop_Id
:= Entity
(Identifier
(Encl_Loop
));
4476 -- Prevent the search from going too far
4478 elsif Is_Body_Or_Package_Declaration
(Stmt
) then
4482 Stmt
:= Parent
(Stmt
);
4485 -- Loop_Entry must appear within a Loop_Assertion pragma (Assert,
4486 -- Assert_And_Cut, Assume count as loop assertion pragmas for this
4487 -- purpose if they appear in an appropriate location in a loop,
4488 -- which was already checked by the top level pragma circuit).
4490 -- Loop_Entry also denotes a value and as such can appear within an
4491 -- expression that is an argument for another loop aspect. In that
4492 -- case it will have been expanded into the corresponding assignment.
4495 and then Nkind
(Parent
(N
)) = N_Assignment_Statement
4496 and then not Comes_From_Source
(Parent
(N
))
4500 elsif No
(Encl_Prag
) then
4501 Error_Attr
("attribute% must appear within appropriate pragma", N
);
4504 -- A Loop_Entry that applies to a given loop statement must not
4505 -- appear within a body of accept statement, if this construct is
4506 -- itself enclosed by the given loop statement.
4508 for Index
in reverse 0 .. Scope_Stack
.Last
loop
4509 Scop
:= Scope_Stack
.Table
(Index
).Entity
;
4511 if Ekind
(Scop
) = E_Loop
and then Scop
= Loop_Id
then
4513 elsif Ekind_In
(Scop
, E_Block
, E_Loop
, E_Return_Statement
) then
4517 ("attribute % cannot appear in body or accept statement", N
);
4522 -- The prefix cannot mention entities declared within the related
4523 -- loop because they will not be visible once the prefix is moved
4524 -- outside the loop.
4526 Check_References_In_Prefix
(Loop_Id
);
4528 -- The prefix must denote a static entity if the pragma does not
4529 -- apply to the innermost enclosing loop statement, or if it appears
4530 -- within a potentially unevaluated epxression.
4532 if Is_Entity_Name
(P
)
4533 or else Nkind
(Parent
(P
)) = N_Object_Renaming_Declaration
4534 or else Statically_Denotes_Object
(P
)
4538 elsif Present
(Encl_Loop
)
4539 and then Entity
(Identifier
(Encl_Loop
)) /= Loop_Id
4542 ("prefix of attribute % that applies to outer loop must denote "
4545 elsif Is_Potentially_Unevaluated
(P
) then
4549 -- Replace the Loop_Entry attribute reference by its prefix if the
4550 -- related pragma is ignored. This transformation is OK with respect
4551 -- to typing because Loop_Entry's type is that of its prefix. This
4552 -- early transformation also avoids the generation of a useless loop
4555 if Present
(Encl_Prag
) and then Is_Ignored
(Encl_Prag
) then
4556 Rewrite
(N
, Relocate_Node
(P
));
4557 Preanalyze_And_Resolve
(N
);
4560 Preanalyze_And_Resolve
(P
);
4568 when Attribute_Machine
=>
4569 Check_Floating_Point_Type_1
;
4570 Set_Etype
(N
, P_Base_Type
);
4571 Resolve
(E1
, P_Base_Type
);
4577 when Attribute_Machine_Emax
=>
4578 Check_Floating_Point_Type_0
;
4579 Set_Etype
(N
, Universal_Integer
);
4585 when Attribute_Machine_Emin
=>
4586 Check_Floating_Point_Type_0
;
4587 Set_Etype
(N
, Universal_Integer
);
4589 ----------------------
4590 -- Machine_Mantissa --
4591 ----------------------
4593 when Attribute_Machine_Mantissa
=>
4594 Check_Floating_Point_Type_0
;
4595 Set_Etype
(N
, Universal_Integer
);
4597 -----------------------
4598 -- Machine_Overflows --
4599 -----------------------
4601 when Attribute_Machine_Overflows
=>
4604 Set_Etype
(N
, Standard_Boolean
);
4610 when Attribute_Machine_Radix
=>
4613 Set_Etype
(N
, Universal_Integer
);
4615 ----------------------
4616 -- Machine_Rounding --
4617 ----------------------
4619 when Attribute_Machine_Rounding
=>
4620 Check_Floating_Point_Type_1
;
4621 Set_Etype
(N
, P_Base_Type
);
4622 Resolve
(E1
, P_Base_Type
);
4624 --------------------
4625 -- Machine_Rounds --
4626 --------------------
4628 when Attribute_Machine_Rounds
=>
4631 Set_Etype
(N
, Standard_Boolean
);
4637 when Attribute_Machine_Size
=>
4640 Check_Not_Incomplete_Type
;
4641 Set_Etype
(N
, Universal_Integer
);
4647 when Attribute_Mantissa
=>
4650 Set_Etype
(N
, Universal_Integer
);
4656 when Attribute_Max
=>
4659 ----------------------------------
4660 -- Max_Alignment_For_Allocation --
4661 ----------------------------------
4663 when Attribute_Max_Size_In_Storage_Elements
=>
4664 Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
;
4666 ----------------------------------
4667 -- Max_Size_In_Storage_Elements --
4668 ----------------------------------
4670 when Attribute_Max_Alignment_For_Allocation
=>
4671 Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
;
4673 -----------------------
4674 -- Maximum_Alignment --
4675 -----------------------
4677 when Attribute_Maximum_Alignment
=>
4678 Standard_Attribute
(Ttypes
.Maximum_Alignment
);
4680 --------------------
4681 -- Mechanism_Code --
4682 --------------------
4684 when Attribute_Mechanism_Code
=>
4685 if not Is_Entity_Name
(P
)
4686 or else not Is_Subprogram
(Entity
(P
))
4688 Error_Attr_P
("prefix of % attribute must be subprogram");
4691 Check_Either_E0_Or_E1
;
4693 if Present
(E1
) then
4694 Resolve
(E1
, Any_Integer
);
4695 Set_Etype
(E1
, Standard_Integer
);
4697 if not Is_OK_Static_Expression
(E1
) then
4698 Flag_Non_Static_Expr
4699 ("expression for parameter number must be static!", E1
);
4702 elsif UI_To_Int
(Intval
(E1
)) > Number_Formals
(Entity
(P
))
4703 or else UI_To_Int
(Intval
(E1
)) < 0
4705 Error_Attr
("invalid parameter number for % attribute", E1
);
4709 Set_Etype
(N
, Universal_Integer
);
4715 when Attribute_Min
=>
4722 when Attribute_Mod
=>
4724 -- Note: this attribute is only allowed in Ada 2005 mode, but
4725 -- we do not need to test that here, since Mod is only recognized
4726 -- as an attribute name in Ada 2005 mode during the parse.
4729 Check_Modular_Integer_Type
;
4730 Resolve
(E1
, Any_Integer
);
4731 Set_Etype
(N
, P_Base_Type
);
4737 when Attribute_Model
=>
4738 Check_Floating_Point_Type_1
;
4739 Set_Etype
(N
, P_Base_Type
);
4740 Resolve
(E1
, P_Base_Type
);
4746 when Attribute_Model_Emin
=>
4747 Check_Floating_Point_Type_0
;
4748 Set_Etype
(N
, Universal_Integer
);
4754 when Attribute_Model_Epsilon
=>
4755 Check_Floating_Point_Type_0
;
4756 Set_Etype
(N
, Universal_Real
);
4758 --------------------
4759 -- Model_Mantissa --
4760 --------------------
4762 when Attribute_Model_Mantissa
=>
4763 Check_Floating_Point_Type_0
;
4764 Set_Etype
(N
, Universal_Integer
);
4770 when Attribute_Model_Small
=>
4771 Check_Floating_Point_Type_0
;
4772 Set_Etype
(N
, Universal_Real
);
4778 when Attribute_Modulus
=>
4780 Check_Modular_Integer_Type
;
4781 Set_Etype
(N
, Universal_Integer
);
4783 --------------------
4784 -- Null_Parameter --
4785 --------------------
4787 when Attribute_Null_Parameter
=> Null_Parameter
: declare
4788 Parnt
: constant Node_Id
:= Parent
(N
);
4789 GParnt
: constant Node_Id
:= Parent
(Parnt
);
4791 procedure Bad_Null_Parameter
(Msg
: String);
4792 -- Used if bad Null parameter attribute node is found. Issues
4793 -- given error message, and also sets the type to Any_Type to
4794 -- avoid blowups later on from dealing with a junk node.
4796 procedure Must_Be_Imported
(Proc_Ent
: Entity_Id
);
4797 -- Called to check that Proc_Ent is imported subprogram
4799 ------------------------
4800 -- Bad_Null_Parameter --
4801 ------------------------
4803 procedure Bad_Null_Parameter
(Msg
: String) is
4805 Error_Msg_N
(Msg
, N
);
4806 Set_Etype
(N
, Any_Type
);
4807 end Bad_Null_Parameter
;
4809 ----------------------
4810 -- Must_Be_Imported --
4811 ----------------------
4813 procedure Must_Be_Imported
(Proc_Ent
: Entity_Id
) is
4814 Pent
: constant Entity_Id
:= Ultimate_Alias
(Proc_Ent
);
4817 -- Ignore check if procedure not frozen yet (we will get
4818 -- another chance when the default parameter is reanalyzed)
4820 if not Is_Frozen
(Pent
) then
4823 elsif not Is_Imported
(Pent
) then
4825 ("Null_Parameter can only be used with imported subprogram");
4830 end Must_Be_Imported
;
4832 -- Start of processing for Null_Parameter
4837 Set_Etype
(N
, P_Type
);
4839 -- Case of attribute used as default expression
4841 if Nkind
(Parnt
) = N_Parameter_Specification
then
4842 Must_Be_Imported
(Defining_Entity
(GParnt
));
4844 -- Case of attribute used as actual for subprogram (positional)
4846 elsif Nkind
(Parnt
) in N_Subprogram_Call
4847 and then Is_Entity_Name
(Name
(Parnt
))
4849 Must_Be_Imported
(Entity
(Name
(Parnt
)));
4851 -- Case of attribute used as actual for subprogram (named)
4853 elsif Nkind
(Parnt
) = N_Parameter_Association
4854 and then Nkind
(GParnt
) in N_Subprogram_Call
4855 and then Is_Entity_Name
(Name
(GParnt
))
4857 Must_Be_Imported
(Entity
(Name
(GParnt
)));
4859 -- Not an allowed case
4863 ("Null_Parameter must be actual or default parameter");
4871 when Attribute_Object_Size
=>
4874 Check_Not_Incomplete_Type
;
4875 Set_Etype
(N
, Universal_Integer
);
4881 when Attribute_Old
=> Old
: declare
4882 procedure Check_References_In_Prefix
(Subp_Id
: Entity_Id
);
4883 -- Inspect the contents of the prefix and detect illegal uses of a
4884 -- nested 'Old, attribute 'Result or a use of an entity declared in
4885 -- the related postcondition expression. Subp_Id is the subprogram to
4886 -- which the related postcondition applies.
4888 --------------------------------
4889 -- Check_References_In_Prefix --
4890 --------------------------------
4892 procedure Check_References_In_Prefix
(Subp_Id
: Entity_Id
) is
4893 function Check_Reference
(Nod
: Node_Id
) return Traverse_Result
;
4894 -- Detect attribute 'Old, attribute 'Result of a use of an entity
4895 -- and perform the appropriate semantic check.
4897 ---------------------
4898 -- Check_Reference --
4899 ---------------------
4901 function Check_Reference
(Nod
: Node_Id
) return Traverse_Result
is
4903 -- Attributes 'Old and 'Result cannot appear in the prefix of
4904 -- another attribute 'Old.
4906 if Nkind
(Nod
) = N_Attribute_Reference
4907 and then Nam_In
(Attribute_Name
(Nod
), Name_Old
,
4910 Error_Msg_Name_1
:= Attribute_Name
(Nod
);
4911 Error_Msg_Name_2
:= Name_Old
;
4913 ("attribute % cannot appear in the prefix of attribute %",
4917 -- Entities mentioned within the prefix of attribute 'Old must
4918 -- be global to the related postcondition. If this is not the
4919 -- case, then the scope of the local entity is nested within
4920 -- that of the subprogram.
4922 elsif Is_Entity_Name
(Nod
)
4923 and then Present
(Entity
(Nod
))
4924 and then Scope_Within
(Scope
(Entity
(Nod
)), Subp_Id
)
4927 ("prefix of attribute % cannot reference local entities",
4931 -- Otherwise keep inspecting the prefix
4936 end Check_Reference
;
4938 procedure Check_References
is new Traverse_Proc
(Check_Reference
);
4940 -- Start of processing for Check_References_In_Prefix
4943 Check_References
(P
);
4944 end Check_References_In_Prefix
;
4949 Pref_Id
: Entity_Id
;
4950 Pref_Typ
: Entity_Id
;
4951 Spec_Id
: Entity_Id
;
4953 -- Start of processing for Old
4956 -- The attribute reference is a primary. If any expressions follow,
4957 -- then the attribute reference is an indexable object. Transform the
4958 -- attribute into an indexed component and analyze it.
4960 if Present
(E1
) then
4962 Make_Indexed_Component
(Loc
,
4964 Make_Attribute_Reference
(Loc
,
4965 Prefix
=> Relocate_Node
(P
),
4966 Attribute_Name
=> Name_Old
),
4967 Expressions
=> Expressions
(N
)));
4972 Analyze_Attribute_Old_Result
(Legal
, Spec_Id
);
4974 -- The aspect or pragma where attribute 'Old resides should be
4975 -- associated with a subprogram declaration or a body. If this is not
4976 -- the case, then the aspect or pragma is illegal. Return as analysis
4977 -- cannot be carried out.
4979 -- The exception to this rule is when generating C since in this case
4980 -- postconditions are inlined.
4983 and then Modify_Tree_For_C
4984 and then In_Inlined_Body
4986 Spec_Id
:= Entity
(P
);
4988 elsif not Legal
then
4992 -- The prefix must be preanalyzed as the full analysis will take
4993 -- place during expansion.
4995 Preanalyze_And_Resolve
(P
);
4997 -- Ensure that the prefix does not contain attributes 'Old or 'Result
4999 Check_References_In_Prefix
(Spec_Id
);
5001 -- Set the type of the attribute now to prevent cascaded errors
5003 Pref_Typ
:= Etype
(P
);
5004 Set_Etype
(N
, Pref_Typ
);
5008 if Is_Limited_Type
(Pref_Typ
) then
5009 Error_Attr
("attribute % cannot apply to limited objects", P
);
5012 -- The prefix is a simple name
5014 if Is_Entity_Name
(P
) and then Present
(Entity
(P
)) then
5015 Pref_Id
:= Entity
(P
);
5017 -- Emit a warning when the prefix is a constant. Note that the use
5018 -- of Error_Attr would reset the type of N to Any_Type even though
5019 -- this is a warning. Use Error_Msg_XXX instead.
5021 if Is_Constant_Object
(Pref_Id
) then
5022 Error_Msg_Name_1
:= Name_Old
;
5024 ("??attribute % applied to constant has no effect", P
);
5027 -- Otherwise the prefix is not a simple name
5030 -- Ensure that the prefix of attribute 'Old is an entity when it
5031 -- is potentially unevaluated (6.1.1 (27/3)).
5033 if Is_Potentially_Unevaluated
(N
)
5034 and then not Statically_Denotes_Object
(P
)
5038 -- Detect a possible infinite recursion when the prefix denotes
5039 -- the related function.
5041 -- function Func (...) return ...
5042 -- with Post => Func'Old ...;
5044 -- The function may be specified in qualified form X.Y where X is
5045 -- a protected object and Y is a protected function. In that case
5046 -- ensure that the qualified form has an entity.
5048 elsif Nkind
(P
) = N_Function_Call
5049 and then Nkind
(Name
(P
)) in N_Has_Entity
5051 Pref_Id
:= Entity
(Name
(P
));
5053 if Ekind_In
(Spec_Id
, E_Function
, E_Generic_Function
)
5054 and then Pref_Id
= Spec_Id
5056 Error_Msg_Warn
:= SPARK_Mode
/= On
;
5057 Error_Msg_N
("!possible infinite recursion<<", P
);
5058 Error_Msg_N
("\!??Storage_Error ]<<", P
);
5062 -- The prefix of attribute 'Old may refer to a component of a
5063 -- formal parameter. In this case its expansion may generate
5064 -- actual subtypes that are referenced in an inner context and
5065 -- that must be elaborated within the subprogram itself. If the
5066 -- prefix includes a function call, it may involve finalization
5067 -- actions that should be inserted when the attribute has been
5068 -- rewritten as a declaration. Create a declaration for the prefix
5069 -- and insert it at the start of the enclosing subprogram. This is
5070 -- an expansion activity that has to be performed now to prevent
5071 -- out-of-order issues.
5073 -- This expansion is both harmful and not needed in SPARK mode,
5074 -- since the formal verification back end relies on the types of
5075 -- nodes (hence is not robust w.r.t. a change to base type here),
5076 -- and does not suffer from the out-of-order issue described
5077 -- above. Thus, this expansion is skipped in SPARK mode.
5079 -- The expansion is not relevant for discrete types, which will
5080 -- not generate extra declarations, and where use of the base type
5081 -- may lead to spurious errors if context is a case.
5083 if not GNATprove_Mode
then
5084 if not Is_Discrete_Type
(Pref_Typ
) then
5085 Pref_Typ
:= Base_Type
(Pref_Typ
);
5088 Set_Etype
(N
, Pref_Typ
);
5089 Set_Etype
(P
, Pref_Typ
);
5091 Analyze_Dimension
(N
);
5097 ----------------------
5098 -- Overlaps_Storage --
5099 ----------------------
5101 when Attribute_Overlaps_Storage
=>
5104 -- Both arguments must be objects of any type
5106 Analyze_And_Resolve
(P
);
5107 Analyze_And_Resolve
(E1
);
5108 Check_Object_Reference
(P
);
5109 Check_Object_Reference
(E1
);
5110 Set_Etype
(N
, Standard_Boolean
);
5116 when Attribute_Output
=>
5118 Check_Stream_Attribute
(TSS_Stream_Output
);
5119 Set_Etype
(N
, Standard_Void_Type
);
5120 Resolve
(N
, Standard_Void_Type
);
5126 when Attribute_Partition_ID
=>
5129 if P_Type
/= Any_Type
then
5130 if not Is_Library_Level_Entity
(Entity
(P
)) then
5132 ("prefix of % attribute must be library-level entity");
5134 -- The defining entity of prefix should not be declared inside a
5135 -- Pure unit. RM E.1(8). Is_Pure was set during declaration.
5137 elsif Is_Entity_Name
(P
)
5138 and then Is_Pure
(Entity
(P
))
5140 Error_Attr_P
("prefix of% attribute must not be declared pure");
5144 Set_Etype
(N
, Universal_Integer
);
5146 -------------------------
5147 -- Passed_By_Reference --
5148 -------------------------
5150 when Attribute_Passed_By_Reference
=>
5153 Set_Etype
(N
, Standard_Boolean
);
5159 when Attribute_Pool_Address
=>
5161 Set_Etype
(N
, RTE
(RE_Address
));
5167 when Attribute_Pos
=>
5168 Check_Discrete_Type
;
5171 if Is_Boolean_Type
(P_Type
) then
5172 Error_Msg_Name_1
:= Aname
;
5173 Error_Msg_Name_2
:= Chars
(P_Type
);
5174 Check_SPARK_05_Restriction
5175 ("attribute% is not allowed for type%", P
);
5178 Resolve
(E1
, P_Base_Type
);
5179 Set_Etype
(N
, Universal_Integer
);
5185 when Attribute_Position
=>
5187 Set_Etype
(N
, Universal_Integer
);
5193 when Attribute_Pred
=>
5197 if Is_Real_Type
(P_Type
) or else Is_Boolean_Type
(P_Type
) then
5198 Error_Msg_Name_1
:= Aname
;
5199 Error_Msg_Name_2
:= Chars
(P_Type
);
5200 Check_SPARK_05_Restriction
5201 ("attribute% is not allowed for type%", P
);
5204 Resolve
(E1
, P_Base_Type
);
5205 Set_Etype
(N
, P_Base_Type
);
5207 -- Since Pred works on the base type, we normally do no check for the
5208 -- floating-point case, since the base type is unconstrained. But we
5209 -- make an exception in Check_Float_Overflow mode.
5211 if Is_Floating_Point_Type
(P_Type
) then
5212 if not Range_Checks_Suppressed
(P_Base_Type
) then
5213 Set_Do_Range_Check
(E1
);
5216 -- If not modular type, test for overflow check required
5219 if not Is_Modular_Integer_Type
(P_Type
)
5220 and then not Range_Checks_Suppressed
(P_Base_Type
)
5222 Enable_Range_Check
(E1
);
5230 -- Ada 2005 (AI-327): Dynamic ceiling priorities
5232 when Attribute_Priority
=>
5233 if Ada_Version
< Ada_2005
then
5234 Error_Attr
("% attribute is allowed only in Ada 2005 mode", P
);
5239 Check_Restriction
(No_Dynamic_Priorities
, N
);
5241 -- The prefix must be a protected object (AARM D.5.2 (2/2))
5245 if Is_Protected_Type
(Etype
(P
))
5246 or else (Is_Access_Type
(Etype
(P
))
5247 and then Is_Protected_Type
(Designated_Type
(Etype
(P
))))
5249 Resolve
(P
, Etype
(P
));
5251 Error_Attr_P
("prefix of % attribute must be a protected object");
5254 Set_Etype
(N
, Standard_Integer
);
5256 -- Must be called from within a protected procedure or entry of the
5257 -- protected object.
5264 while S
/= Etype
(P
)
5265 and then S
/= Standard_Standard
5270 if S
= Standard_Standard
then
5271 Error_Attr
("the attribute % is only allowed inside protected "
5276 Validate_Non_Static_Attribute_Function_Call
;
5282 when Attribute_Range
=>
5283 Check_Array_Or_Scalar_Type
;
5284 Bad_Attribute_For_Predicate
;
5286 if Ada_Version
= Ada_83
5287 and then Is_Scalar_Type
(P_Type
)
5288 and then Comes_From_Source
(N
)
5291 ("(Ada 83) % attribute not allowed for scalar type", P
);
5298 when Attribute_Result
=> Result
: declare
5299 function Denote_Same_Function
5300 (Pref_Id
: Entity_Id
;
5301 Spec_Id
: Entity_Id
) return Boolean;
5302 -- Determine whether the entity of the prefix Pref_Id denotes the
5303 -- same entity as that of the related subprogram Spec_Id.
5305 --------------------------
5306 -- Denote_Same_Function --
5307 --------------------------
5309 function Denote_Same_Function
5310 (Pref_Id
: Entity_Id
;
5311 Spec_Id
: Entity_Id
) return Boolean
5313 Over_Id
: constant Entity_Id
:= Overridden_Operation
(Spec_Id
);
5314 Subp_Spec
: constant Node_Id
:= Parent
(Spec_Id
);
5317 -- The prefix denotes the related subprogram
5319 if Pref_Id
= Spec_Id
then
5322 -- Account for a special case when attribute 'Result appears in
5323 -- the postcondition of a generic function.
5326 -- function Gen_Func return ...
5327 -- with Post => Gen_Func'Result ...;
5329 -- When the generic function is instantiated, the Chars field of
5330 -- the instantiated prefix still denotes the name of the generic
5331 -- function. Note that any preemptive transformation is impossible
5332 -- without a proper analysis. The structure of the wrapper package
5335 -- package Anon_Gen_Pack is
5336 -- <subtypes and renamings>
5337 -- function Subp_Decl return ...; -- (!)
5338 -- pragma Postcondition (Gen_Func'Result ...); -- (!)
5339 -- function Gen_Func ... renames Subp_Decl;
5340 -- end Anon_Gen_Pack;
5342 elsif Nkind
(Subp_Spec
) = N_Function_Specification
5343 and then Present
(Generic_Parent
(Subp_Spec
))
5344 and then Ekind_In
(Pref_Id
, E_Generic_Function
, E_Function
)
5346 if Generic_Parent
(Subp_Spec
) = Pref_Id
then
5349 elsif Present
(Alias
(Pref_Id
))
5350 and then Alias
(Pref_Id
) = Spec_Id
5355 -- Account for a special case where a primitive of a tagged type
5356 -- inherits a class-wide postcondition from a parent type. In this
5357 -- case the prefix of attribute 'Result denotes the overriding
5360 elsif Present
(Over_Id
) and then Pref_Id
= Over_Id
then
5364 -- Otherwise the prefix does not denote the related subprogram
5367 end Denote_Same_Function
;
5371 In_Inlined_C_Postcondition
: constant Boolean :=
5373 and then In_Inlined_Body
;
5376 Pref_Id
: Entity_Id
;
5377 Spec_Id
: Entity_Id
;
5379 -- Start of processing for Result
5382 -- The attribute reference is a primary. If any expressions follow,
5383 -- then the attribute reference is an indexable object. Transform the
5384 -- attribute into an indexed component and analyze it.
5386 if Present
(E1
) then
5388 Make_Indexed_Component
(Loc
,
5390 Make_Attribute_Reference
(Loc
,
5391 Prefix
=> Relocate_Node
(P
),
5392 Attribute_Name
=> Name_Result
),
5393 Expressions
=> Expressions
(N
)));
5398 Analyze_Attribute_Old_Result
(Legal
, Spec_Id
);
5400 -- The aspect or pragma where attribute 'Result resides should be
5401 -- associated with a subprogram declaration or a body. If this is not
5402 -- the case, then the aspect or pragma is illegal. Return as analysis
5403 -- cannot be carried out.
5405 -- The exception to this rule is when generating C since in this case
5406 -- postconditions are inlined.
5408 if No
(Spec_Id
) and then In_Inlined_C_Postcondition
then
5409 Spec_Id
:= Entity
(P
);
5411 elsif not Legal
then
5415 -- Attribute 'Result is part of a _Postconditions procedure. There is
5416 -- no need to perform the semantic checks below as they were already
5417 -- verified when the attribute was analyzed in its original context.
5418 -- Instead, rewrite the attribute as a reference to formal parameter
5419 -- _Result of the _Postconditions procedure.
5421 if Chars
(Spec_Id
) = Name_uPostconditions
5423 (In_Inlined_C_Postcondition
5424 and then Nkind
(Parent
(Spec_Id
)) = N_Block_Statement
)
5426 Rewrite
(N
, Make_Identifier
(Loc
, Name_uResult
));
5428 -- The type of formal parameter _Result is that of the function
5429 -- encapsulating the _Postconditions procedure. Resolution must
5430 -- be carried out against the function return type.
5432 Analyze_And_Resolve
(N
, Etype
(Scope
(Spec_Id
)));
5434 -- Otherwise attribute 'Result appears in its original context and
5435 -- all semantic checks should be carried out.
5438 -- Verify the legality of the prefix. It must denotes the entity
5439 -- of the related [generic] function.
5441 if Is_Entity_Name
(P
) then
5442 Pref_Id
:= Entity
(P
);
5444 if Ekind_In
(Pref_Id
, E_Function
, E_Generic_Function
)
5445 and then Ekind
(Spec_Id
) = Ekind
(Pref_Id
)
5447 if Denote_Same_Function
(Pref_Id
, Spec_Id
) then
5449 -- Correct the prefix of the attribute when the context
5450 -- is a generic function.
5452 if Pref_Id
/= Spec_Id
then
5453 Rewrite
(P
, New_Occurrence_Of
(Spec_Id
, Loc
));
5457 Set_Etype
(N
, Etype
(Spec_Id
));
5459 -- Otherwise the prefix denotes some unrelated function
5462 Error_Msg_Name_2
:= Chars
(Spec_Id
);
5464 ("incorrect prefix for attribute %, expected %", P
);
5467 -- Otherwise the prefix denotes some other form of subprogram
5472 ("attribute % can only appear in postcondition of "
5476 -- Otherwise the prefix is illegal
5479 Error_Msg_Name_2
:= Chars
(Spec_Id
);
5480 Error_Attr
("incorrect prefix for attribute %, expected %", P
);
5489 when Attribute_Range_Length
=>
5491 Check_Discrete_Type
;
5492 Set_Etype
(N
, Universal_Integer
);
5498 when Attribute_Read
=>
5500 Check_Stream_Attribute
(TSS_Stream_Read
);
5501 Set_Etype
(N
, Standard_Void_Type
);
5502 Resolve
(N
, Standard_Void_Type
);
5503 Note_Possible_Modification
(E2
, Sure
=> True);
5509 when Attribute_Ref
=>
5513 if Nkind
(P
) /= N_Expanded_Name
5514 or else not Is_RTE
(P_Type
, RE_Address
)
5516 Error_Attr_P
("prefix of % attribute must be System.Address");
5519 Analyze_And_Resolve
(E1
, Any_Integer
);
5520 Set_Etype
(N
, RTE
(RE_Address
));
5526 when Attribute_Remainder
=>
5527 Check_Floating_Point_Type_2
;
5528 Set_Etype
(N
, P_Base_Type
);
5529 Resolve
(E1
, P_Base_Type
);
5530 Resolve
(E2
, P_Base_Type
);
5532 ---------------------
5533 -- Restriction_Set --
5534 ---------------------
5536 when Attribute_Restriction_Set
=> Restriction_Set
: declare
5539 Unam
: Unit_Name_Type
;
5544 Check_System_Prefix
;
5546 -- No_Dependence case
5548 if Nkind
(E1
) = N_Parameter_Association
then
5549 pragma Assert
(Chars
(Selector_Name
(E1
)) = Name_No_Dependence
);
5550 U
:= Explicit_Actual_Parameter
(E1
);
5552 if not OK_No_Dependence_Unit_Name
(U
) then
5553 Set_Boolean_Result
(N
, False);
5557 -- See if there is an entry already in the table. That's the
5558 -- case in which we can return True.
5560 for J
in No_Dependences
.First
.. No_Dependences
.Last
loop
5561 if Designate_Same_Unit
(U
, No_Dependences
.Table
(J
).Unit
)
5562 and then No_Dependences
.Table
(J
).Warn
= False
5564 Set_Boolean_Result
(N
, True);
5569 -- If not in the No_Dependence table, result is False
5571 Set_Boolean_Result
(N
, False);
5573 -- In this case, we must ensure that the binder will reject any
5574 -- other unit in the partition that sets No_Dependence for this
5575 -- unit. We do that by making an entry in the special table kept
5576 -- for this purpose (if the entry is not there already).
5578 Unam
:= Get_Spec_Name
(Get_Unit_Name
(U
));
5580 for J
in Restriction_Set_Dependences
.First
..
5581 Restriction_Set_Dependences
.Last
5583 if Restriction_Set_Dependences
.Table
(J
) = Unam
then
5588 Restriction_Set_Dependences
.Append
(Unam
);
5590 -- Normal restriction case
5593 if Nkind
(E1
) /= N_Identifier
then
5594 Set_Boolean_Result
(N
, False);
5595 Error_Attr
("attribute % requires restriction identifier", E1
);
5598 R
:= Get_Restriction_Id
(Process_Restriction_Synonyms
(E1
));
5600 if R
= Not_A_Restriction_Id
then
5601 Set_Boolean_Result
(N
, False);
5602 Error_Msg_Node_1
:= E1
;
5603 Error_Attr
("invalid restriction identifier &", E1
);
5605 elsif R
not in Partition_Boolean_Restrictions
then
5606 Set_Boolean_Result
(N
, False);
5607 Error_Msg_Node_1
:= E1
;
5609 ("& is not a boolean partition-wide restriction", E1
);
5612 if Restriction_Active
(R
) then
5613 Set_Boolean_Result
(N
, True);
5615 Check_Restriction
(R
, N
);
5616 Set_Boolean_Result
(N
, False);
5620 end Restriction_Set
;
5626 when Attribute_Round
=>
5628 Check_Decimal_Fixed_Point_Type
;
5629 Set_Etype
(N
, P_Base_Type
);
5631 -- Because the context is universal_real (3.5.10(12)) it is a
5632 -- legal context for a universal fixed expression. This is the
5633 -- only attribute whose functional description involves U_R.
5635 if Etype
(E1
) = Universal_Fixed
then
5637 Conv
: constant Node_Id
:= Make_Type_Conversion
(Loc
,
5638 Subtype_Mark
=> New_Occurrence_Of
(Universal_Real
, Loc
),
5639 Expression
=> Relocate_Node
(E1
));
5647 Resolve
(E1
, Any_Real
);
5653 when Attribute_Rounding
=>
5654 Check_Floating_Point_Type_1
;
5655 Set_Etype
(N
, P_Base_Type
);
5656 Resolve
(E1
, P_Base_Type
);
5662 when Attribute_Safe_Emax
=>
5663 Check_Floating_Point_Type_0
;
5664 Set_Etype
(N
, Universal_Integer
);
5670 when Attribute_Safe_First
=>
5671 Check_Floating_Point_Type_0
;
5672 Set_Etype
(N
, Universal_Real
);
5678 when Attribute_Safe_Large
=>
5681 Set_Etype
(N
, Universal_Real
);
5687 when Attribute_Safe_Last
=>
5688 Check_Floating_Point_Type_0
;
5689 Set_Etype
(N
, Universal_Real
);
5695 when Attribute_Safe_Small
=>
5698 Set_Etype
(N
, Universal_Real
);
5700 --------------------------
5701 -- Scalar_Storage_Order --
5702 --------------------------
5704 when Attribute_Scalar_Storage_Order
=> Scalar_Storage_Order
: declare
5705 Ent
: Entity_Id
:= Empty
;
5711 if not (Is_Record_Type
(P_Type
) or else Is_Array_Type
(P_Type
)) then
5713 -- The attribute applies to generic private types (in which case
5714 -- the legality rule is applied in the instance) as well as to
5715 -- composite types. For noncomposite types it always returns the
5716 -- default bit order for the target.
5717 -- Allowing formal private types was originally introduced in
5718 -- GNAT_Mode only, to compile instances of Sequential_IO, but
5719 -- users find it more generally useful in generic units.
5721 if not (Is_Generic_Type
(P_Type
) and then Is_Private_Type
(P_Type
))
5722 and then not In_Instance
5725 ("prefix of % attribute must be record or array type");
5727 elsif not Is_Generic_Type
(P_Type
) then
5728 if Bytes_Big_Endian
then
5729 Ent
:= RTE
(RE_High_Order_First
);
5731 Ent
:= RTE
(RE_Low_Order_First
);
5735 elsif Bytes_Big_Endian
xor Reverse_Storage_Order
(P_Type
) then
5736 Ent
:= RTE
(RE_High_Order_First
);
5739 Ent
:= RTE
(RE_Low_Order_First
);
5742 if Present
(Ent
) then
5743 Rewrite
(N
, New_Occurrence_Of
(Ent
, Loc
));
5746 Set_Etype
(N
, RTE
(RE_Bit_Order
));
5749 -- Reset incorrect indication of staticness
5751 Set_Is_Static_Expression
(N
, False);
5752 end Scalar_Storage_Order
;
5758 when Attribute_Scale
=>
5760 Check_Decimal_Fixed_Point_Type
;
5761 Set_Etype
(N
, Universal_Integer
);
5767 when Attribute_Scaling
=>
5768 Check_Floating_Point_Type_2
;
5769 Set_Etype
(N
, P_Base_Type
);
5770 Resolve
(E1
, P_Base_Type
);
5776 when Attribute_Signed_Zeros
=>
5777 Check_Floating_Point_Type_0
;
5778 Set_Etype
(N
, Standard_Boolean
);
5785 | Attribute_VADS_Size
5789 -- If prefix is parameterless function call, rewrite and resolve
5792 if Is_Entity_Name
(P
)
5793 and then Ekind
(Entity
(P
)) = E_Function
5797 -- Similar processing for a protected function call
5799 elsif Nkind
(P
) = N_Selected_Component
5800 and then Ekind
(Entity
(Selector_Name
(P
))) = E_Function
5805 if Is_Object_Reference
(P
) then
5806 Check_Object_Reference
(P
);
5808 elsif Is_Entity_Name
(P
)
5809 and then (Is_Type
(Entity
(P
))
5810 or else Ekind
(Entity
(P
)) = E_Enumeration_Literal
)
5814 elsif Nkind
(P
) = N_Type_Conversion
5815 and then not Comes_From_Source
(P
)
5819 -- Some other compilers allow dubious use of X'???'Size
5821 elsif Relaxed_RM_Semantics
5822 and then Nkind
(P
) = N_Attribute_Reference
5827 Error_Attr_P
("invalid prefix for % attribute");
5830 Check_Not_Incomplete_Type
;
5832 Set_Etype
(N
, Universal_Integer
);
5834 -- If we are processing pragmas Compile_Time_Warning and Compile_
5835 -- Time_Errors after the back end has been called and this occurrence
5836 -- of 'Size is known at compile time then it is safe to perform this
5837 -- evaluation. Needed to perform the static evaluation of the full
5838 -- boolean expression of these pragmas.
5840 if In_Compile_Time_Warning_Or_Error
5841 and then Is_Entity_Name
(P
)
5842 and then (Is_Type
(Entity
(P
))
5843 or else Ekind
(Entity
(P
)) = E_Enumeration_Literal
)
5844 and then Size_Known_At_Compile_Time
(Entity
(P
))
5846 Rewrite
(N
, Make_Integer_Literal
(Sloc
(N
), Esize
(Entity
(P
))));
5854 when Attribute_Small
=>
5857 Set_Etype
(N
, Universal_Real
);
5863 when Attribute_Storage_Pool
5864 | Attribute_Simple_Storage_Pool
5868 if Is_Access_Type
(P_Type
) then
5869 if Ekind
(P_Type
) = E_Access_Subprogram_Type
then
5871 ("cannot use % attribute for access-to-subprogram type");
5874 -- Set appropriate entity
5876 if Present
(Associated_Storage_Pool
(Root_Type
(P_Type
))) then
5877 Set_Entity
(N
, Associated_Storage_Pool
(Root_Type
(P_Type
)));
5879 Set_Entity
(N
, RTE
(RE_Global_Pool_Object
));
5882 if Attr_Id
= Attribute_Storage_Pool
then
5883 if Present
(Get_Rep_Pragma
(Etype
(Entity
(N
)),
5884 Name_Simple_Storage_Pool_Type
))
5886 Error_Msg_Name_1
:= Aname
;
5887 Error_Msg_Warn
:= SPARK_Mode
/= On
;
5889 ("cannot use % attribute for type with simple storage "
5891 Error_Msg_N
("\Program_Error [<<", N
);
5894 (N
, Make_Raise_Program_Error
5895 (Sloc
(N
), Reason
=> PE_Explicit_Raise
));
5898 Set_Etype
(N
, Class_Wide_Type
(RTE
(RE_Root_Storage_Pool
)));
5900 -- In the Simple_Storage_Pool case, verify that the pool entity is
5901 -- actually of a simple storage pool type, and set the attribute's
5902 -- type to the pool object's type.
5905 if not Present
(Get_Rep_Pragma
(Etype
(Entity
(N
)),
5906 Name_Simple_Storage_Pool_Type
))
5909 ("cannot use % attribute for type without simple " &
5913 Set_Etype
(N
, Etype
(Entity
(N
)));
5916 -- Validate_Remote_Access_To_Class_Wide_Type for attribute
5917 -- Storage_Pool since this attribute is not defined for such
5918 -- types (RM E.2.3(22)).
5920 Validate_Remote_Access_To_Class_Wide_Type
(N
);
5923 Error_Attr_P
("prefix of % attribute must be access type");
5930 when Attribute_Storage_Size
=>
5933 if Is_Task_Type
(P_Type
) then
5934 Set_Etype
(N
, Universal_Integer
);
5936 -- Use with tasks is an obsolescent feature
5938 Check_Restriction
(No_Obsolescent_Features
, P
);
5940 elsif Is_Access_Type
(P_Type
) then
5941 if Ekind
(P_Type
) = E_Access_Subprogram_Type
then
5943 ("cannot use % attribute for access-to-subprogram type");
5946 if Is_Entity_Name
(P
)
5947 and then Is_Type
(Entity
(P
))
5950 Set_Etype
(N
, Universal_Integer
);
5952 -- Validate_Remote_Access_To_Class_Wide_Type for attribute
5953 -- Storage_Size since this attribute is not defined for
5954 -- such types (RM E.2.3(22)).
5956 Validate_Remote_Access_To_Class_Wide_Type
(N
);
5958 -- The prefix is allowed to be an implicit dereference of an
5959 -- access value designating a task.
5963 Set_Etype
(N
, Universal_Integer
);
5967 Error_Attr_P
("prefix of % attribute must be access or task type");
5974 when Attribute_Storage_Unit
=>
5975 Standard_Attribute
(Ttypes
.System_Storage_Unit
);
5981 when Attribute_Stream_Size
=>
5985 if Is_Entity_Name
(P
)
5986 and then Is_Elementary_Type
(Entity
(P
))
5988 Set_Etype
(N
, Universal_Integer
);
5990 Error_Attr_P
("invalid prefix for % attribute");
5997 when Attribute_Stub_Type
=>
6001 if Is_Remote_Access_To_Class_Wide_Type
(Base_Type
(P_Type
)) then
6003 -- For a real RACW [sub]type, use corresponding stub type
6005 if not Is_Generic_Type
(P_Type
) then
6008 (Corresponding_Stub_Type
(Base_Type
(P_Type
)), Loc
));
6010 -- For a generic type (that has been marked as an RACW using the
6011 -- Remote_Access_Type aspect or pragma), use a generic RACW stub
6012 -- type. Note that if the actual is not a remote access type, the
6013 -- instantiation will fail.
6016 -- Note: we go to the underlying type here because the view
6017 -- returned by RTE (RE_RACW_Stub_Type) might be incomplete.
6021 (Underlying_Type
(RTE
(RE_RACW_Stub_Type
)), Loc
));
6026 ("prefix of% attribute must be remote access-to-class-wide");
6033 when Attribute_Succ
=>
6037 if Is_Real_Type
(P_Type
) or else Is_Boolean_Type
(P_Type
) then
6038 Error_Msg_Name_1
:= Aname
;
6039 Error_Msg_Name_2
:= Chars
(P_Type
);
6040 Check_SPARK_05_Restriction
6041 ("attribute% is not allowed for type%", P
);
6044 Resolve
(E1
, P_Base_Type
);
6045 Set_Etype
(N
, P_Base_Type
);
6047 -- Since Pred works on the base type, we normally do no check for the
6048 -- floating-point case, since the base type is unconstrained. But we
6049 -- make an exception in Check_Float_Overflow mode.
6051 if Is_Floating_Point_Type
(P_Type
) then
6052 if not Range_Checks_Suppressed
(P_Base_Type
) then
6053 Set_Do_Range_Check
(E1
);
6056 -- If not modular type, test for overflow check required
6059 if not Is_Modular_Integer_Type
(P_Type
)
6060 and then not Range_Checks_Suppressed
(P_Base_Type
)
6062 Enable_Range_Check
(E1
);
6066 --------------------------------
6067 -- System_Allocator_Alignment --
6068 --------------------------------
6070 when Attribute_System_Allocator_Alignment
=>
6071 Standard_Attribute
(Ttypes
.System_Allocator_Alignment
);
6077 when Attribute_Tag
=>
6081 if not Is_Tagged_Type
(P_Type
) then
6082 Error_Attr_P
("prefix of % attribute must be tagged");
6084 -- Next test does not apply to generated code why not, and what does
6085 -- the illegal reference mean???
6087 elsif Is_Object_Reference
(P
)
6088 and then not Is_Class_Wide_Type
(P_Type
)
6089 and then Comes_From_Source
(N
)
6092 ("% attribute can only be applied to objects " &
6093 "of class - wide type");
6096 -- The prefix cannot be an incomplete type. However, references to
6097 -- 'Tag can be generated when expanding interface conversions, and
6100 if Comes_From_Source
(N
) then
6101 Check_Not_Incomplete_Type
;
6104 -- Set appropriate type
6106 Set_Etype
(N
, RTE
(RE_Tag
));
6112 when Attribute_Target_Name
=> Target_Name
: declare
6113 TN
: constant String := Sdefault
.Target_Name
.all;
6117 Check_Standard_Prefix
;
6121 if TN
(TL
) = '/' or else TN
(TL
) = '\' then
6126 Make_String_Literal
(Loc
,
6127 Strval
=> TN
(TN
'First .. TL
)));
6128 Analyze_And_Resolve
(N
, Standard_String
);
6129 Set_Is_Static_Expression
(N
, True);
6136 when Attribute_Terminated
=>
6138 Set_Etype
(N
, Standard_Boolean
);
6145 when Attribute_To_Address
=> To_Address
: declare
6150 Check_System_Prefix
;
6152 Generate_Reference
(RTE
(RE_Address
), P
);
6153 Analyze_And_Resolve
(E1
, Any_Integer
);
6154 Set_Etype
(N
, RTE
(RE_Address
));
6155 Set_Is_Static_Expression
(N
, Is_Static_Expression
(E1
));
6157 -- OK static expression case, check range and set appropriate type
6159 if Is_OK_Static_Expression
(E1
) then
6160 Val
:= Expr_Value
(E1
);
6162 if Val
< -(2 ** UI_From_Int
(Standard
'Address_Size - 1))
6164 Val
> 2 ** UI_From_Int
(Standard
'Address_Size) - 1
6166 Error_Attr
("address value out of range for % attribute", E1
);
6169 -- In most cases the expression is a numeric literal or some other
6170 -- address expression, but if it is a declared constant it may be
6171 -- of a compatible type that must be left on the node.
6173 if Is_Entity_Name
(E1
) then
6176 -- Set type to universal integer if negative
6179 Set_Etype
(E1
, Universal_Integer
);
6181 -- Otherwise set type to Unsigned_64 to accommodate max values
6184 Set_Etype
(E1
, Standard_Unsigned_64
);
6193 when Attribute_To_Any
=>
6195 Check_PolyORB_Attribute
;
6196 Set_Etype
(N
, RTE
(RE_Any
));
6202 when Attribute_Truncation
=>
6203 Check_Floating_Point_Type_1
;
6204 Resolve
(E1
, P_Base_Type
);
6205 Set_Etype
(N
, P_Base_Type
);
6211 when Attribute_Type_Class
=>
6214 Check_Not_Incomplete_Type
;
6215 Set_Etype
(N
, RTE
(RE_Type_Class
));
6221 when Attribute_TypeCode
=>
6223 Check_PolyORB_Attribute
;
6224 Set_Etype
(N
, RTE
(RE_TypeCode
));
6230 when Attribute_Type_Key
=> Type_Key
: declare
6231 Full_Name
: constant String_Id
:=
6232 Fully_Qualified_Name_String
(Entity
(P
));
6235 -- The computed signature for the type
6238 -- To simplify the handling of mutually recursive types, follow a
6239 -- single dereference link in a composite type.
6241 procedure Compute_Type_Key
(T
: Entity_Id
);
6242 -- Create a CRC integer from the declaration of the type. For a
6243 -- composite type, fold in the representation of its components in
6244 -- recursive fashion. We use directly the source representation of
6245 -- the types involved.
6247 ----------------------
6248 -- Compute_Type_Key --
6249 ----------------------
6251 procedure Compute_Type_Key
(T
: Entity_Id
) is
6252 Buffer
: Source_Buffer_Ptr
;
6256 SFI
: Source_File_Index
;
6258 procedure Process_One_Declaration
;
6259 -- Update CRC with the characters of one type declaration, or a
6260 -- representation pragma that applies to the type.
6262 -----------------------------
6263 -- Process_One_Declaration --
6264 -----------------------------
6266 procedure Process_One_Declaration
is
6268 -- Scan type declaration, skipping blanks
6270 for Ptr
in P_Min
.. P_Max
loop
6271 if Buffer
(Ptr
) /= ' ' then
6272 System
.CRC32
.Update
(CRC
, Buffer
(Ptr
));
6275 end Process_One_Declaration
;
6277 -- Start of processing for Compute_Type_Key
6280 if Is_Itype
(T
) then
6284 -- If the type is declared in Standard, there is no source, so
6285 -- just use its name.
6287 if Scope
(T
) = Standard_Standard
then
6289 Name
: constant String := Get_Name_String
(Chars
(T
));
6291 for J
in Name
'Range loop
6292 System
.CRC32
.Update
(CRC
, Name
(J
));
6299 Sloc_Range
(Enclosing_Declaration
(T
), P_Min
, P_Max
);
6300 SFI
:= Get_Source_File_Index
(P_Min
);
6301 pragma Assert
(SFI
= Get_Source_File_Index
(P_Max
));
6302 Buffer
:= Source_Text
(SFI
);
6304 Process_One_Declaration
;
6306 -- Recurse on relevant component types
6308 if Is_Array_Type
(T
) then
6309 Compute_Type_Key
(Component_Type
(T
));
6311 elsif Is_Access_Type
(T
) then
6314 Compute_Type_Key
(Designated_Type
(T
));
6317 elsif Is_Derived_Type
(T
) then
6318 Compute_Type_Key
(Etype
(T
));
6320 elsif Is_Record_Type
(T
) then
6324 Comp
:= First_Component
(T
);
6325 while Present
(Comp
) loop
6326 Compute_Type_Key
(Etype
(Comp
));
6327 Next_Component
(Comp
);
6332 if Is_First_Subtype
(T
) then
6334 -- Fold in representation aspects for the type, which appear in
6335 -- the same source buffer. If the representation aspects are in
6336 -- a different source file, then skip them; they apply to some
6337 -- other type, perhaps one we're derived from.
6339 Rep
:= First_Rep_Item
(T
);
6341 while Present
(Rep
) loop
6342 if Comes_From_Source
(Rep
) then
6343 Sloc_Range
(Rep
, P_Min
, P_Max
);
6345 if SFI
= Get_Source_File_Index
(P_Min
) then
6346 pragma Assert
(SFI
= Get_Source_File_Index
(P_Max
));
6347 Process_One_Declaration
;
6351 Rep
:= Next_Rep_Item
(Rep
);
6354 end Compute_Type_Key
;
6356 -- Start of processing for Type_Key
6365 -- Copy all characters in Full_Name but the trailing NUL
6367 for J
in 1 .. String_Length
(Full_Name
) - 1 loop
6368 Store_String_Char
(Get_String_Char
(Full_Name
, Pos
(J
)));
6371 -- Compute CRC and convert it to string one character at a time, so
6372 -- as not to use Image within the compiler.
6375 Compute_Type_Key
(Entity
(P
));
6377 if not Is_Frozen
(Entity
(P
)) then
6378 Error_Msg_N
("premature usage of Type_Key?", N
);
6382 Store_String_Char
(Character'Val (48 + (CRC
rem 10)));
6386 Rewrite
(N
, Make_String_Literal
(Loc
, End_String
));
6387 Analyze_And_Resolve
(N
, Standard_String
);
6390 -----------------------
6391 -- Unbiased_Rounding --
6392 -----------------------
6394 when Attribute_Unbiased_Rounding
=>
6395 Check_Floating_Point_Type_1
;
6396 Set_Etype
(N
, P_Base_Type
);
6397 Resolve
(E1
, P_Base_Type
);
6399 ----------------------
6400 -- Unchecked_Access --
6401 ----------------------
6403 when Attribute_Unchecked_Access
=>
6404 if Comes_From_Source
(N
) then
6405 Check_Restriction
(No_Unchecked_Access
, N
);
6408 Analyze_Access_Attribute
;
6409 Check_Not_Incomplete_Type
;
6411 -------------------------
6412 -- Unconstrained_Array --
6413 -------------------------
6415 when Attribute_Unconstrained_Array
=>
6418 Check_Not_Incomplete_Type
;
6419 Set_Etype
(N
, Standard_Boolean
);
6420 Set_Is_Static_Expression
(N
, True);
6422 ------------------------------
6423 -- Universal_Literal_String --
6424 ------------------------------
6426 -- This is a GNAT specific attribute whose prefix must be a named
6427 -- number where the expression is either a single numeric literal,
6428 -- or a numeric literal immediately preceded by a minus sign. The
6429 -- result is equivalent to a string literal containing the text of
6430 -- the literal as it appeared in the source program with a possible
6431 -- leading minus sign.
6433 when Attribute_Universal_Literal_String
=>
6436 if not Is_Entity_Name
(P
)
6437 or else Ekind
(Entity
(P
)) not in Named_Kind
6439 Error_Attr_P
("prefix for % attribute must be named number");
6446 Src
: Source_Buffer_Ptr
;
6449 Expr
:= Original_Node
(Expression
(Parent
(Entity
(P
))));
6451 if Nkind
(Expr
) = N_Op_Minus
then
6453 Expr
:= Original_Node
(Right_Opnd
(Expr
));
6458 if not Nkind_In
(Expr
, N_Integer_Literal
, N_Real_Literal
) then
6460 ("named number for % attribute must be simple literal", N
);
6463 -- Build string literal corresponding to source literal text
6468 Store_String_Char
(Get_Char_Code
('-'));
6472 Src
:= Source_Text
(Get_Source_File_Index
(S
));
6474 while Src
(S
) /= ';' and then Src
(S
) /= ' ' loop
6475 Store_String_Char
(Get_Char_Code
(Src
(S
)));
6479 -- Now we rewrite the attribute with the string literal
6482 Make_String_Literal
(Loc
, End_String
));
6484 Set_Is_Static_Expression
(N
, True);
6488 -------------------------
6489 -- Unrestricted_Access --
6490 -------------------------
6492 -- This is a GNAT specific attribute which is like Access except that
6493 -- all scope checks and checks for aliased views are omitted. It is
6494 -- documented as being equivalent to the use of the Address attribute
6495 -- followed by an unchecked conversion to the target access type.
6497 when Attribute_Unrestricted_Access
=>
6499 -- If from source, deal with relevant restrictions
6501 if Comes_From_Source
(N
) then
6502 Check_Restriction
(No_Unchecked_Access
, N
);
6504 if Nkind
(P
) in N_Has_Entity
6505 and then Present
(Entity
(P
))
6506 and then Is_Object
(Entity
(P
))
6508 Check_Restriction
(No_Implicit_Aliasing
, N
);
6512 if Is_Entity_Name
(P
) then
6513 Set_Address_Taken
(Entity
(P
));
6516 -- It might seem reasonable to call Address_Checks here to apply the
6517 -- same set of semantic checks that we enforce for 'Address (after
6518 -- all we document Unrestricted_Access as being equivalent to the
6519 -- use of Address followed by an Unchecked_Conversion). However, if
6520 -- we do enable these checks, we get multiple failures in both the
6521 -- compiler run-time and in our regression test suite, so we leave
6522 -- out these checks for now. To be investigated further some time???
6526 -- Now complete analysis using common access processing
6528 Analyze_Access_Attribute
;
6534 when Attribute_Update
=> Update
: declare
6535 Common_Typ
: Entity_Id
;
6536 -- The common type of a multiple component update for a record
6538 Comps
: Elist_Id
:= No_Elist
;
6539 -- A list used in the resolution of a record update. It contains the
6540 -- entities of all record components processed so far.
6542 procedure Analyze_Array_Component_Update
(Assoc
: Node_Id
);
6543 -- Analyze and resolve array_component_association Assoc against the
6544 -- index of array type P_Type.
6546 procedure Analyze_Record_Component_Update
(Comp
: Node_Id
);
6547 -- Analyze and resolve record_component_association Comp against
6548 -- record type P_Type.
6550 ------------------------------------
6551 -- Analyze_Array_Component_Update --
6552 ------------------------------------
6554 procedure Analyze_Array_Component_Update
(Assoc
: Node_Id
) is
6558 Index_Typ
: Entity_Id
;
6562 -- The current association contains a sequence of indexes denoting
6563 -- an element of a multidimensional array:
6565 -- (Index_1, ..., Index_N)
6567 -- Examine each individual index and resolve it against the proper
6568 -- index type of the array.
6570 if Nkind
(First
(Choices
(Assoc
))) = N_Aggregate
then
6571 Expr
:= First
(Choices
(Assoc
));
6572 while Present
(Expr
) loop
6574 -- The use of others is illegal (SPARK RM 4.4.1(12))
6576 if Nkind
(Expr
) = N_Others_Choice
then
6578 ("others choice not allowed in attribute %", Expr
);
6580 -- Otherwise analyze and resolve all indexes
6583 Index
:= First
(Expressions
(Expr
));
6584 Index_Typ
:= First_Index
(P_Type
);
6585 while Present
(Index
) and then Present
(Index_Typ
) loop
6586 Analyze_And_Resolve
(Index
, Etype
(Index_Typ
));
6588 Next_Index
(Index_Typ
);
6591 -- Detect a case where the association either lacks an
6592 -- index or contains an extra index.
6594 if Present
(Index
) or else Present
(Index_Typ
) then
6596 ("dimension mismatch in index list", Assoc
);
6603 -- The current association denotes either a single component or a
6604 -- range of components of a one dimensional array:
6608 -- Resolve the index or its high and low bounds (if range) against
6609 -- the proper index type of the array.
6612 Index
:= First
(Choices
(Assoc
));
6613 Index_Typ
:= First_Index
(P_Type
);
6615 if Present
(Next_Index
(Index_Typ
)) then
6616 Error_Msg_N
("too few subscripts in array reference", Assoc
);
6619 while Present
(Index
) loop
6621 -- The use of others is illegal (SPARK RM 4.4.1(12))
6623 if Nkind
(Index
) = N_Others_Choice
then
6625 ("others choice not allowed in attribute %", Index
);
6627 -- The index denotes a range of elements
6629 elsif Nkind
(Index
) = N_Range
then
6630 Low
:= Low_Bound
(Index
);
6631 High
:= High_Bound
(Index
);
6633 Analyze_And_Resolve
(Low
, Etype
(Index_Typ
));
6634 Analyze_And_Resolve
(High
, Etype
(Index_Typ
));
6636 -- Add a range check to ensure that the bounds of the
6637 -- range are within the index type when this cannot be
6638 -- determined statically.
6640 if not Is_OK_Static_Expression
(Low
) then
6641 Set_Do_Range_Check
(Low
);
6644 if not Is_OK_Static_Expression
(High
) then
6645 Set_Do_Range_Check
(High
);
6648 -- Otherwise the index denotes a single element
6651 Analyze_And_Resolve
(Index
, Etype
(Index_Typ
));
6653 -- Add a range check to ensure that the index is within
6654 -- the index type when it is not possible to determine
6657 if not Is_OK_Static_Expression
(Index
) then
6658 Set_Do_Range_Check
(Index
);
6665 end Analyze_Array_Component_Update
;
6667 -------------------------------------
6668 -- Analyze_Record_Component_Update --
6669 -------------------------------------
6671 procedure Analyze_Record_Component_Update
(Comp
: Node_Id
) is
6672 Comp_Name
: constant Name_Id
:= Chars
(Comp
);
6673 Base_Typ
: Entity_Id
;
6674 Comp_Or_Discr
: Entity_Id
;
6677 -- Find the discriminant or component whose name corresponds to
6678 -- Comp. A simple character comparison is sufficient because all
6679 -- visible names within a record type are unique.
6681 Comp_Or_Discr
:= First_Entity
(P_Type
);
6682 while Present
(Comp_Or_Discr
) loop
6683 if Chars
(Comp_Or_Discr
) = Comp_Name
then
6685 -- Decorate the component reference by setting its entity
6686 -- and type for resolution purposes.
6688 Set_Entity
(Comp
, Comp_Or_Discr
);
6689 Set_Etype
(Comp
, Etype
(Comp_Or_Discr
));
6693 Comp_Or_Discr
:= Next_Entity
(Comp_Or_Discr
);
6696 -- Diagnose an illegal reference
6698 if Present
(Comp_Or_Discr
) then
6699 if Ekind
(Comp_Or_Discr
) = E_Discriminant
then
6701 ("attribute % may not modify record discriminants", Comp
);
6703 else pragma Assert
(Ekind
(Comp_Or_Discr
) = E_Component
);
6704 if Contains
(Comps
, Comp_Or_Discr
) then
6705 Error_Msg_N
("component & already updated", Comp
);
6707 -- Mark this component as processed
6710 Append_New_Elmt
(Comp_Or_Discr
, Comps
);
6714 -- The update aggregate mentions an entity that does not belong to
6718 Error_Msg_N
("& is not a component of aggregate subtype", Comp
);
6721 -- Verify the consistency of types when the current component is
6722 -- part of a miltiple component update.
6724 -- Comp_1, ..., Comp_N => <value>
6726 if Present
(Etype
(Comp
)) then
6727 Base_Typ
:= Base_Type
(Etype
(Comp
));
6729 -- Save the type of the first component reference as the
6730 -- remaning references (if any) must resolve to this type.
6732 if No
(Common_Typ
) then
6733 Common_Typ
:= Base_Typ
;
6735 elsif Base_Typ
/= Common_Typ
then
6737 ("components in choice list must have same type", Comp
);
6740 end Analyze_Record_Component_Update
;
6747 -- Start of processing for Update
6752 if not Is_Object_Reference
(P
) then
6753 Error_Attr_P
("prefix of attribute % must denote an object");
6755 elsif not Is_Array_Type
(P_Type
)
6756 and then not Is_Record_Type
(P_Type
)
6758 Error_Attr_P
("prefix of attribute % must be a record or array");
6760 elsif Is_Limited_View
(P_Type
) then
6761 Error_Attr
("prefix of attribute % cannot be limited", N
);
6763 elsif Nkind
(E1
) /= N_Aggregate
then
6764 Error_Attr
("attribute % requires component association list", N
);
6767 -- Inspect the update aggregate, looking at all the associations and
6768 -- choices. Perform the following checks:
6770 -- 1) Legality of "others" in all cases
6771 -- 2) Legality of <>
6772 -- 3) Component legality for arrays
6773 -- 4) Component legality for records
6775 -- The remaining checks are performed on the expanded attribute
6777 Assoc
:= First
(Component_Associations
(E1
));
6778 while Present
(Assoc
) loop
6780 -- The use of <> is illegal (SPARK RM 4.4.1(1))
6782 if Box_Present
(Assoc
) then
6784 ("default initialization not allowed in attribute %", Assoc
);
6786 -- Otherwise process the association
6789 Analyze
(Expression
(Assoc
));
6791 if Is_Array_Type
(P_Type
) then
6792 Analyze_Array_Component_Update
(Assoc
);
6794 elsif Is_Record_Type
(P_Type
) then
6796 -- Reset the common type used in a multiple component update
6797 -- as we are processing the contents of a new association.
6799 Common_Typ
:= Empty
;
6801 Comp
:= First
(Choices
(Assoc
));
6802 while Present
(Comp
) loop
6803 if Nkind
(Comp
) = N_Identifier
then
6804 Analyze_Record_Component_Update
(Comp
);
6806 -- The use of others is illegal (SPARK RM 4.4.1(5))
6808 elsif Nkind
(Comp
) = N_Others_Choice
then
6810 ("others choice not allowed in attribute %", Comp
);
6812 -- The name of a record component cannot appear in any
6817 ("name should be identifier or OTHERS", Comp
);
6828 -- The type of attribute 'Update is that of the prefix
6830 Set_Etype
(N
, P_Type
);
6832 Sem_Warn
.Warn_On_Suspicious_Update
(N
);
6839 when Attribute_Val
=>
6841 Check_Discrete_Type
;
6843 if Is_Boolean_Type
(P_Type
) then
6844 Error_Msg_Name_1
:= Aname
;
6845 Error_Msg_Name_2
:= Chars
(P_Type
);
6846 Check_SPARK_05_Restriction
6847 ("attribute% is not allowed for type%", P
);
6850 -- Note, we need a range check in general, but we wait for the
6851 -- Resolve call to do this, since we want to let Eval_Attribute
6852 -- have a chance to find an static illegality first.
6854 Resolve
(E1
, Any_Integer
);
6855 Set_Etype
(N
, P_Base_Type
);
6861 when Attribute_Valid
=> Valid
: declare
6862 Pred_Func
: constant Entity_Id
:= Predicate_Function
(P_Type
);
6867 -- Ignore check for object if we have a 'Valid reference generated
6868 -- by the expanded code, since in some cases valid checks can occur
6869 -- on items that are names, but are not objects (e.g. attributes).
6871 if Comes_From_Source
(N
) then
6872 Check_Object_Reference
(P
);
6874 if not Is_Scalar_Type
(P_Type
) then
6875 Error_Attr_P
("object for % attribute must be of scalar type");
6878 -- If the attribute appears within the subtype's own predicate
6879 -- function, then issue a warning that this will cause infinite
6882 if Present
(Pred_Func
) and then Current_Scope
= Pred_Func
then
6883 Error_Msg_N
("attribute Valid requires a predicate check??", N
);
6884 Error_Msg_N
("\and will result in infinite recursion??", N
);
6888 Set_Etype
(N
, Standard_Boolean
);
6895 when Attribute_Valid_Scalars
=> Valid_Scalars
: declare
6899 if Comes_From_Source
(N
) then
6900 Check_Object_Reference
(P
);
6902 -- Do not emit any diagnostics related to private types to avoid
6903 -- disclosing the structure of the type.
6905 if Is_Private_Type
(P_Type
) then
6907 -- Attribute 'Valid_Scalars is not supported on private tagged
6908 -- types due to a code generation issue. Is_Visible_Component
6909 -- does not allow for a component of a private tagged type to
6910 -- be successfully retrieved.
6912 -- Do not use Error_Attr_P because this bypasses any subsequent
6913 -- processing and leaves the attribute with type Any_Type. This
6914 -- in turn prevents the proper expansion of the attribute into
6917 if Is_Tagged_Type
(P_Type
) then
6918 Error_Msg_Name_1
:= Aname
;
6919 Error_Msg_N
("??effects of attribute % are ignored", N
);
6922 -- Otherwise the type is not private
6925 if not Scalar_Part_Present
(P_Type
) then
6926 Error_Msg_Name_1
:= Aname
;
6928 ("??attribute % always True, no scalars to check", P
);
6929 Set_Boolean_Result
(N
, True);
6932 -- Attribute 'Valid_Scalars is illegal on unchecked union types
6933 -- because it is not always guaranteed that the components are
6934 -- retrievable based on whether the discriminants are inferable
6936 if Has_Unchecked_Union
(P_Type
) then
6938 ("attribute % not allowed for Unchecked_Union type");
6943 Set_Etype
(N
, Standard_Boolean
);
6950 when Attribute_Value
=>
6951 Check_SPARK_05_Restriction_On_Attribute
;
6955 -- Case of enumeration type
6957 -- When an enumeration type appears in an attribute reference, all
6958 -- literals of the type are marked as referenced. This must only be
6959 -- done if the attribute reference appears in the current source.
6960 -- Otherwise the information on references may differ between a
6961 -- normal compilation and one that performs inlining.
6963 if Is_Enumeration_Type
(P_Type
)
6964 and then In_Extended_Main_Code_Unit
(N
)
6966 Check_Restriction
(No_Enumeration_Maps
, N
);
6968 -- Mark all enumeration literals as referenced, since the use of
6969 -- the Value attribute can implicitly reference any of the
6970 -- literals of the enumeration base type.
6973 Ent
: Entity_Id
:= First_Literal
(P_Base_Type
);
6975 while Present
(Ent
) loop
6976 Set_Referenced
(Ent
);
6982 -- Set Etype before resolving expression because expansion of
6983 -- expression may require enclosing type. Note that the type
6984 -- returned by 'Value is the base type of the prefix type.
6986 Set_Etype
(N
, P_Base_Type
);
6987 Validate_Non_Static_Attribute_Function_Call
;
6989 -- Check restriction No_Fixed_IO
6991 if Restriction_Check_Required
(No_Fixed_IO
)
6992 and then Is_Fixed_Point_Type
(P_Type
)
6994 Check_Restriction
(No_Fixed_IO
, P
);
7001 when Attribute_Value_Size
=>
7004 Check_Not_Incomplete_Type
;
7005 Set_Etype
(N
, Universal_Integer
);
7011 when Attribute_Version
=>
7014 Set_Etype
(N
, RTE
(RE_Version_String
));
7020 when Attribute_Wchar_T_Size
=>
7021 Standard_Attribute
(Interfaces_Wchar_T_Size
);
7027 when Attribute_Wide_Image
=>
7028 Analyze_Image_Attribute
(Standard_Wide_String
);
7030 ---------------------
7031 -- Wide_Wide_Image --
7032 ---------------------
7034 when Attribute_Wide_Wide_Image
=>
7035 Analyze_Image_Attribute
(Standard_Wide_Wide_String
);
7041 when Attribute_Wide_Value
=>
7042 Check_SPARK_05_Restriction_On_Attribute
;
7046 -- Set Etype before resolving expression because expansion
7047 -- of expression may require enclosing type.
7049 Set_Etype
(N
, P_Type
);
7050 Validate_Non_Static_Attribute_Function_Call
;
7052 -- Check restriction No_Fixed_IO
7054 if Restriction_Check_Required
(No_Fixed_IO
)
7055 and then Is_Fixed_Point_Type
(P_Type
)
7057 Check_Restriction
(No_Fixed_IO
, P
);
7060 ---------------------
7061 -- Wide_Wide_Value --
7062 ---------------------
7064 when Attribute_Wide_Wide_Value
=>
7068 -- Set Etype before resolving expression because expansion
7069 -- of expression may require enclosing type.
7071 Set_Etype
(N
, P_Type
);
7072 Validate_Non_Static_Attribute_Function_Call
;
7074 -- Check restriction No_Fixed_IO
7076 if Restriction_Check_Required
(No_Fixed_IO
)
7077 and then Is_Fixed_Point_Type
(P_Type
)
7079 Check_Restriction
(No_Fixed_IO
, P
);
7082 ---------------------
7083 -- Wide_Wide_Width --
7084 ---------------------
7086 when Attribute_Wide_Wide_Width
=>
7089 Set_Etype
(N
, Universal_Integer
);
7095 when Attribute_Wide_Width
=>
7096 Check_SPARK_05_Restriction_On_Attribute
;
7099 Set_Etype
(N
, Universal_Integer
);
7105 when Attribute_Width
=>
7106 Check_SPARK_05_Restriction_On_Attribute
;
7109 Set_Etype
(N
, Universal_Integer
);
7115 when Attribute_Word_Size
=>
7116 Standard_Attribute
(System_Word_Size
);
7122 when Attribute_Write
=>
7124 Check_Stream_Attribute
(TSS_Stream_Write
);
7125 Set_Etype
(N
, Standard_Void_Type
);
7126 Resolve
(N
, Standard_Void_Type
);
7130 -- In SPARK certain attributes (see below) depend on Tasking_State.
7131 -- Ensure that the entity is available for gnat2why by loading it.
7132 -- See SPARK RM 9(18) for the relevant rule.
7134 if GNATprove_Mode
then
7140 when Attribute_Callable
7143 | Attribute_Terminated
7145 Unused
:= RTE
(RE_Tasking_State
);
7153 -- All errors raise Bad_Attribute, so that we get out before any further
7154 -- damage occurs when an error is detected (for example, if we check for
7155 -- one attribute expression, and the check succeeds, we want to be able
7156 -- to proceed securely assuming that an expression is in fact present.
7158 -- Note: we set the attribute analyzed in this case to prevent any
7159 -- attempt at reanalysis which could generate spurious error msgs.
7162 when Bad_Attribute
=>
7164 Set_Etype
(N
, Any_Type
);
7166 end Analyze_Attribute
;
7168 --------------------
7169 -- Eval_Attribute --
7170 --------------------
7172 procedure Eval_Attribute
(N
: Node_Id
) is
7173 Loc
: constant Source_Ptr
:= Sloc
(N
);
7174 Aname
: constant Name_Id
:= Attribute_Name
(N
);
7175 Id
: constant Attribute_Id
:= Get_Attribute_Id
(Aname
);
7176 P
: constant Node_Id
:= Prefix
(N
);
7178 C_Type
: constant Entity_Id
:= Etype
(N
);
7179 -- The type imposed by the context
7182 -- First expression, or Empty if none
7185 -- Second expression, or Empty if none
7187 P_Entity
: Entity_Id
;
7188 -- Entity denoted by prefix
7191 -- The type of the prefix
7193 P_Base_Type
: Entity_Id
;
7194 -- The base type of the prefix type
7196 P_Root_Type
: Entity_Id
;
7197 -- The root type of the prefix type
7199 Static
: Boolean := False;
7200 -- True if the result is Static. This is set by the general processing
7201 -- to true if the prefix is static, and all expressions are static. It
7202 -- can be reset as processing continues for particular attributes. This
7203 -- flag can still be True if the reference raises a constraint error.
7204 -- Is_Static_Expression (N) is set to follow this value as it is set
7205 -- and we could always reference this, but it is convenient to have a
7206 -- simple short name to use, since it is frequently referenced.
7208 Lo_Bound
, Hi_Bound
: Node_Id
;
7209 -- Expressions for low and high bounds of type or array index referenced
7210 -- by First, Last, or Length attribute for array, set by Set_Bounds.
7213 -- Constraint error node used if we have an attribute reference has
7214 -- an argument that raises a constraint error. In this case we replace
7215 -- the attribute with a raise constraint_error node. This is important
7216 -- processing, since otherwise gigi might see an attribute which it is
7217 -- unprepared to deal with.
7219 procedure Check_Concurrent_Discriminant
(Bound
: Node_Id
);
7220 -- If Bound is a reference to a discriminant of a task or protected type
7221 -- occurring within the object's body, rewrite attribute reference into
7222 -- a reference to the corresponding discriminal. Use for the expansion
7223 -- of checks against bounds of entry family index subtypes.
7225 procedure Check_Expressions
;
7226 -- In case where the attribute is not foldable, the expressions, if
7227 -- any, of the attribute, are in a non-static context. This procedure
7228 -- performs the required additional checks.
7230 function Compile_Time_Known_Bounds
(Typ
: Entity_Id
) return Boolean;
7231 -- Determines if the given type has compile time known bounds. Note
7232 -- that we enter the case statement even in cases where the prefix
7233 -- type does NOT have known bounds, so it is important to guard any
7234 -- attempt to evaluate both bounds with a call to this function.
7236 procedure Compile_Time_Known_Attribute
(N
: Node_Id
; Val
: Uint
);
7237 -- This procedure is called when the attribute N has a non-static
7238 -- but compile time known value given by Val. It includes the
7239 -- necessary checks for out of range values.
7241 function Fore_Value
return Nat
;
7242 -- Computes the Fore value for the current attribute prefix, which is
7243 -- known to be a static fixed-point type. Used by Fore and Width.
7245 function Mantissa
return Uint
;
7246 -- Returns the Mantissa value for the prefix type
7248 procedure Set_Bounds
;
7249 -- Used for First, Last and Length attributes applied to an array or
7250 -- array subtype. Sets the variables Lo_Bound and Hi_Bound to the low
7251 -- and high bound expressions for the index referenced by the attribute
7252 -- designator (i.e. the first index if no expression is present, and the
7253 -- N'th index if the value N is present as an expression). Also used for
7254 -- First and Last of scalar types and for First_Valid and Last_Valid.
7255 -- Static is reset to False if the type or index type is not statically
7258 function Statically_Denotes_Entity
(N
: Node_Id
) return Boolean;
7259 -- Verify that the prefix of a potentially static array attribute
7260 -- satisfies the conditions of 4.9 (14).
7262 -----------------------------------
7263 -- Check_Concurrent_Discriminant --
7264 -----------------------------------
7266 procedure Check_Concurrent_Discriminant
(Bound
: Node_Id
) is
7268 -- The concurrent (task or protected) type
7271 if Nkind
(Bound
) = N_Identifier
7272 and then Ekind
(Entity
(Bound
)) = E_Discriminant
7273 and then Is_Concurrent_Record_Type
(Scope
(Entity
(Bound
)))
7275 Tsk
:= Corresponding_Concurrent_Type
(Scope
(Entity
(Bound
)));
7277 if In_Open_Scopes
(Tsk
) and then Has_Completion
(Tsk
) then
7279 -- Find discriminant of original concurrent type, and use
7280 -- its current discriminal, which is the renaming within
7281 -- the task/protected body.
7285 (Find_Body_Discriminal
(Entity
(Bound
)), Loc
));
7288 end Check_Concurrent_Discriminant
;
7290 -----------------------
7291 -- Check_Expressions --
7292 -----------------------
7294 procedure Check_Expressions
is
7298 while Present
(E
) loop
7299 Check_Non_Static_Context
(E
);
7302 end Check_Expressions
;
7304 ----------------------------------
7305 -- Compile_Time_Known_Attribute --
7306 ----------------------------------
7308 procedure Compile_Time_Known_Attribute
(N
: Node_Id
; Val
: Uint
) is
7309 T
: constant Entity_Id
:= Etype
(N
);
7312 Fold_Uint
(N
, Val
, False);
7314 -- Check that result is in bounds of the type if it is static
7316 if Is_In_Range
(N
, T
, Assume_Valid
=> False) then
7319 elsif Is_Out_Of_Range
(N
, T
) then
7320 Apply_Compile_Time_Constraint_Error
7321 (N
, "value not in range of}??", CE_Range_Check_Failed
);
7323 elsif not Range_Checks_Suppressed
(T
) then
7324 Enable_Range_Check
(N
);
7327 Set_Do_Range_Check
(N
, False);
7329 end Compile_Time_Known_Attribute
;
7331 -------------------------------
7332 -- Compile_Time_Known_Bounds --
7333 -------------------------------
7335 function Compile_Time_Known_Bounds
(Typ
: Entity_Id
) return Boolean is
7338 Compile_Time_Known_Value
(Type_Low_Bound
(Typ
))
7340 Compile_Time_Known_Value
(Type_High_Bound
(Typ
));
7341 end Compile_Time_Known_Bounds
;
7347 -- Note that the Fore calculation is based on the actual values
7348 -- of the bounds, and does not take into account possible rounding.
7350 function Fore_Value
return Nat
is
7351 Lo
: constant Uint
:= Expr_Value
(Type_Low_Bound
(P_Type
));
7352 Hi
: constant Uint
:= Expr_Value
(Type_High_Bound
(P_Type
));
7353 Small
: constant Ureal
:= Small_Value
(P_Type
);
7354 Lo_Real
: constant Ureal
:= Lo
* Small
;
7355 Hi_Real
: constant Ureal
:= Hi
* Small
;
7360 -- Bounds are given in terms of small units, so first compute
7361 -- proper values as reals.
7363 T
:= UR_Max
(abs Lo_Real
, abs Hi_Real
);
7366 -- Loop to compute proper value if more than one digit required
7368 while T
>= Ureal_10
loop
7380 -- Table of mantissa values accessed by function Computed using
7383 -- T'Mantissa = integer next above (D * log(10)/log(2)) + 1)
7385 -- where D is T'Digits (RM83 3.5.7)
7387 Mantissa_Value
: constant array (Nat
range 1 .. 40) of Nat
:= (
7429 function Mantissa
return Uint
is
7432 UI_From_Int
(Mantissa_Value
(UI_To_Int
(Digits_Value
(P_Type
))));
7439 procedure Set_Bounds
is
7445 -- For a string literal subtype, we have to construct the bounds.
7446 -- Valid Ada code never applies attributes to string literals, but
7447 -- it is convenient to allow the expander to generate attribute
7448 -- references of this type (e.g. First and Last applied to a string
7451 -- Note that the whole point of the E_String_Literal_Subtype is to
7452 -- avoid this construction of bounds, but the cases in which we
7453 -- have to materialize them are rare enough that we don't worry.
7455 -- The low bound is simply the low bound of the base type. The
7456 -- high bound is computed from the length of the string and this
7459 if Ekind
(P_Type
) = E_String_Literal_Subtype
then
7460 Ityp
:= Etype
(First_Index
(Base_Type
(P_Type
)));
7461 Lo_Bound
:= Type_Low_Bound
(Ityp
);
7464 Make_Integer_Literal
(Sloc
(P
),
7466 Expr_Value
(Lo_Bound
) + String_Literal_Length
(P_Type
) - 1);
7468 Set_Parent
(Hi_Bound
, P
);
7469 Analyze_And_Resolve
(Hi_Bound
, Etype
(Lo_Bound
));
7472 -- For non-array case, just get bounds of scalar type
7474 elsif Is_Scalar_Type
(P_Type
) then
7477 -- For a fixed-point type, we must freeze to get the attributes
7478 -- of the fixed-point type set now so we can reference them.
7480 if Is_Fixed_Point_Type
(P_Type
)
7481 and then not Is_Frozen
(Base_Type
(P_Type
))
7482 and then Compile_Time_Known_Value
(Type_Low_Bound
(P_Type
))
7483 and then Compile_Time_Known_Value
(Type_High_Bound
(P_Type
))
7485 Freeze_Fixed_Point_Type
(Base_Type
(P_Type
));
7488 -- For array case, get type of proper index
7494 Ndim
:= UI_To_Int
(Expr_Value
(E1
));
7497 Indx
:= First_Index
(P_Type
);
7498 for J
in 1 .. Ndim
- 1 loop
7502 -- If no index type, get out (some other error occurred, and
7503 -- we don't have enough information to complete the job).
7511 Ityp
:= Etype
(Indx
);
7514 -- A discrete range in an index constraint is allowed to be a
7515 -- subtype indication. This is syntactically a pain, but should
7516 -- not propagate to the entity for the corresponding index subtype.
7517 -- After checking that the subtype indication is legal, the range
7518 -- of the subtype indication should be transfered to the entity.
7519 -- The attributes for the bounds should remain the simple retrievals
7520 -- that they are now.
7522 Lo_Bound
:= Type_Low_Bound
(Ityp
);
7523 Hi_Bound
:= Type_High_Bound
(Ityp
);
7525 -- If subtype is non-static, result is definitely non-static
7527 if not Is_Static_Subtype
(Ityp
) then
7529 Set_Is_Static_Expression
(N
, False);
7531 -- Subtype is static, does it raise CE?
7533 elsif not Is_OK_Static_Subtype
(Ityp
) then
7534 Set_Raises_Constraint_Error
(N
);
7538 -------------------------------
7539 -- Statically_Denotes_Entity --
7540 -------------------------------
7542 function Statically_Denotes_Entity
(N
: Node_Id
) return Boolean is
7546 if not Is_Entity_Name
(N
) then
7553 Nkind
(Parent
(E
)) /= N_Object_Renaming_Declaration
7554 or else Statically_Denotes_Entity
(Renamed_Object
(E
));
7555 end Statically_Denotes_Entity
;
7557 -- Start of processing for Eval_Attribute
7560 -- The To_Address attribute can be static, but it cannot be evaluated at
7561 -- compile time, so just return.
7563 if Id
= Attribute_To_Address
then
7567 -- Initialize result as non-static, will be reset if appropriate
7569 Set_Is_Static_Expression
(N
, False);
7571 -- Acquire first two expressions (at the moment, no attributes take more
7572 -- than two expressions in any case).
7574 if Present
(Expressions
(N
)) then
7575 E1
:= First
(Expressions
(N
));
7582 -- Special processing for Enabled attribute. This attribute has a very
7583 -- special prefix, and the easiest way to avoid lots of special checks
7584 -- to protect this special prefix from causing trouble is to deal with
7585 -- this attribute immediately and be done with it.
7587 if Id
= Attribute_Enabled
then
7589 -- We skip evaluation if the expander is not active. This is not just
7590 -- an optimization. It is of key importance that we not rewrite the
7591 -- attribute in a generic template, since we want to pick up the
7592 -- setting of the check in the instance, Testing Expander_Active
7593 -- might seem an easy way of doing this, but we need to account for
7594 -- ASIS needs, so check explicitly for a generic context.
7596 if not Inside_A_Generic
then
7598 C
: constant Check_Id
:= Get_Check_Id
(Chars
(P
));
7603 if C
in Predefined_Check_Id
then
7604 R
:= Scope_Suppress
.Suppress
(C
);
7606 R
:= Is_Check_Suppressed
(Empty
, C
);
7610 R
:= Is_Check_Suppressed
(Entity
(E1
), C
);
7613 Rewrite
(N
, New_Occurrence_Of
(Boolean_Literals
(not R
), Loc
));
7620 -- Attribute 'Img applied to a static enumeration value is static, and
7621 -- we will do the folding right here (things get confused if we let this
7622 -- case go through the normal circuitry).
7624 if Attribute_Name
(N
) = Name_Img
7625 and then Is_Entity_Name
(P
)
7626 and then Is_Enumeration_Type
(Etype
(Entity
(P
)))
7627 and then Is_OK_Static_Expression
(P
)
7630 Lit
: constant Entity_Id
:= Expr_Value_E
(P
);
7635 Get_Unqualified_Decoded_Name_String
(Chars
(Lit
));
7636 Set_Casing
(All_Upper_Case
);
7637 Store_String_Chars
(Name_Buffer
(1 .. Name_Len
));
7640 Rewrite
(N
, Make_String_Literal
(Loc
, Strval
=> Str
));
7641 Analyze_And_Resolve
(N
, Standard_String
);
7642 Set_Is_Static_Expression
(N
, True);
7648 -- Special processing for cases where the prefix is an object. For this
7649 -- purpose, a string literal counts as an object (attributes of string
7650 -- literals can only appear in generated code).
7652 if Is_Object_Reference
(P
) or else Nkind
(P
) = N_String_Literal
then
7654 -- For Component_Size, the prefix is an array object, and we apply
7655 -- the attribute to the type of the object. This is allowed for both
7656 -- unconstrained and constrained arrays, since the bounds have no
7657 -- influence on the value of this attribute.
7659 if Id
= Attribute_Component_Size
then
7660 P_Entity
:= Etype
(P
);
7662 -- For Enum_Rep, evaluation depends on the nature of the prefix and
7663 -- the optional argument.
7665 elsif Id
= Attribute_Enum_Rep
then
7666 if Is_Entity_Name
(P
) then
7669 Enum_Expr
: Node_Id
;
7670 -- The enumeration-type expression of interest
7675 if Ekind_In
(Entity
(P
), E_Constant
,
7676 E_Enumeration_Literal
)
7680 -- Enum_Type'Enum_Rep (E1) case
7682 elsif Is_Enumeration_Type
(Entity
(P
)) then
7685 -- Otherwise the attribute must be expanded into a
7686 -- conversion and evaluated at run time.
7693 -- We can fold if the expression is an enumeration
7694 -- literal, or if it denotes a constant whose value
7695 -- is known at compile time.
7697 if Nkind
(Enum_Expr
) in N_Has_Entity
7698 and then (Ekind
(Entity
(Enum_Expr
)) =
7699 E_Enumeration_Literal
7701 (Ekind
(Entity
(Enum_Expr
)) = E_Constant
7702 and then Nkind
(Parent
(Entity
(Enum_Expr
))) =
7703 N_Object_Declaration
7704 and then Compile_Time_Known_Value
7705 (Expression
(Parent
(Entity
(P
))))))
7707 P_Entity
:= Etype
(P
);
7714 -- Otherwise the attribute is illegal, do not attempt to perform
7715 -- any kind of folding.
7721 -- For First and Last, the prefix is an array object, and we apply
7722 -- the attribute to the type of the array, but we need a constrained
7723 -- type for this, so we use the actual subtype if available.
7725 elsif Id
= Attribute_First
or else
7726 Id
= Attribute_Last
or else
7727 Id
= Attribute_Length
7730 AS
: constant Entity_Id
:= Get_Actual_Subtype_If_Available
(P
);
7733 if Present
(AS
) and then Is_Constrained
(AS
) then
7736 -- If we have an unconstrained type we cannot fold
7744 -- For Size, give size of object if available, otherwise we
7745 -- cannot fold Size.
7747 elsif Id
= Attribute_Size
then
7748 if Is_Entity_Name
(P
)
7749 and then Known_Esize
(Entity
(P
))
7751 Compile_Time_Known_Attribute
(N
, Esize
(Entity
(P
)));
7759 -- For Alignment, give size of object if available, otherwise we
7760 -- cannot fold Alignment.
7762 elsif Id
= Attribute_Alignment
then
7763 if Is_Entity_Name
(P
)
7764 and then Known_Alignment
(Entity
(P
))
7766 Fold_Uint
(N
, Alignment
(Entity
(P
)), Static
);
7774 -- For Lock_Free, we apply the attribute to the type of the object.
7775 -- This is allowed since we have already verified that the type is a
7778 elsif Id
= Attribute_Lock_Free
then
7779 P_Entity
:= Etype
(P
);
7781 -- No other attributes for objects are folded
7788 -- Cases where P is not an object. Cannot do anything if P is not the
7789 -- name of an entity.
7791 elsif not Is_Entity_Name
(P
) then
7795 -- Otherwise get prefix entity
7798 P_Entity
:= Entity
(P
);
7801 -- If we are asked to evaluate an attribute where the prefix is a
7802 -- non-frozen generic actual type whose RM_Size is still set to zero,
7803 -- then abandon the effort.
7805 if Is_Type
(P_Entity
)
7806 and then (not Is_Frozen
(P_Entity
)
7807 and then Is_Generic_Actual_Type
(P_Entity
)
7808 and then RM_Size
(P_Entity
) = 0)
7810 -- However, the attribute Unconstrained_Array must be evaluated,
7811 -- since it is documented to be a static attribute (and can for
7812 -- example appear in a Compile_Time_Warning pragma). The frozen
7813 -- status of the type does not affect its evaluation.
7815 and then Id
/= Attribute_Unconstrained_Array
7820 -- At this stage P_Entity is the entity to which the attribute
7821 -- is to be applied. This is usually simply the entity of the
7822 -- prefix, except in some cases of attributes for objects, where
7823 -- as described above, we apply the attribute to the object type.
7825 -- Here is where we make sure that static attributes are properly
7826 -- marked as such. These are attributes whose prefix is a static
7827 -- scalar subtype, whose result is scalar, and whose arguments, if
7828 -- present, are static scalar expressions. Note that such references
7829 -- are static expressions even if they raise Constraint_Error.
7831 -- For example, Boolean'Pos (1/0 = 0) is a static expression, even
7832 -- though evaluating it raises constraint error. This means that a
7833 -- declaration like:
7835 -- X : constant := (if True then 1 else Boolean'Pos (1/0 = 0));
7837 -- is legal, since here this expression appears in a statically
7838 -- unevaluated position, so it does not actually raise an exception.
7840 if Is_Scalar_Type
(P_Entity
)
7841 and then (not Is_Generic_Type
(P_Entity
))
7842 and then Is_Static_Subtype
(P_Entity
)
7843 and then Is_Scalar_Type
(Etype
(N
))
7846 or else (Is_Static_Expression
(E1
)
7847 and then Is_Scalar_Type
(Etype
(E1
))))
7850 or else (Is_Static_Expression
(E2
)
7851 and then Is_Scalar_Type
(Etype
(E1
))))
7854 Set_Is_Static_Expression
(N
, True);
7857 -- First foldable possibility is a scalar or array type (RM 4.9(7))
7858 -- that is not generic (generic types are eliminated by RM 4.9(25)).
7859 -- Note we allow non-static non-generic types at this stage as further
7862 if Is_Type
(P_Entity
)
7863 and then (Is_Scalar_Type
(P_Entity
) or Is_Array_Type
(P_Entity
))
7864 and then (not Is_Generic_Type
(P_Entity
))
7868 -- Second foldable possibility is an array object (RM 4.9(8))
7870 elsif Ekind_In
(P_Entity
, E_Variable
, E_Constant
)
7871 and then Is_Array_Type
(Etype
(P_Entity
))
7872 and then (not Is_Generic_Type
(Etype
(P_Entity
)))
7874 P_Type
:= Etype
(P_Entity
);
7876 -- If the entity is an array constant with an unconstrained nominal
7877 -- subtype then get the type from the initial value. If the value has
7878 -- been expanded into assignments, there is no expression and the
7879 -- attribute reference remains dynamic.
7881 -- We could do better here and retrieve the type ???
7883 if Ekind
(P_Entity
) = E_Constant
7884 and then not Is_Constrained
(P_Type
)
7886 if No
(Constant_Value
(P_Entity
)) then
7889 P_Type
:= Etype
(Constant_Value
(P_Entity
));
7893 -- Definite must be folded if the prefix is not a generic type, that
7894 -- is to say if we are within an instantiation. Same processing applies
7895 -- to the GNAT attributes Atomic_Always_Lock_Free, Has_Discriminants,
7896 -- Lock_Free, Type_Class, Has_Tagged_Value, and Unconstrained_Array.
7898 elsif (Id
= Attribute_Atomic_Always_Lock_Free
or else
7899 Id
= Attribute_Definite
or else
7900 Id
= Attribute_Has_Access_Values
or else
7901 Id
= Attribute_Has_Discriminants
or else
7902 Id
= Attribute_Has_Tagged_Values
or else
7903 Id
= Attribute_Lock_Free
or else
7904 Id
= Attribute_Type_Class
or else
7905 Id
= Attribute_Unconstrained_Array
or else
7906 Id
= Attribute_Max_Alignment_For_Allocation
)
7907 and then not Is_Generic_Type
(P_Entity
)
7911 -- We can fold 'Size applied to a type if the size is known (as happens
7912 -- for a size from an attribute definition clause). At this stage, this
7913 -- can happen only for types (e.g. record types) for which the size is
7914 -- always non-static. We exclude generic types from consideration (since
7915 -- they have bogus sizes set within templates).
7917 elsif Id
= Attribute_Size
7918 and then Is_Type
(P_Entity
)
7919 and then (not Is_Generic_Type
(P_Entity
))
7920 and then Known_Static_RM_Size
(P_Entity
)
7922 Compile_Time_Known_Attribute
(N
, RM_Size
(P_Entity
));
7925 -- We can fold 'Alignment applied to a type if the alignment is known
7926 -- (as happens for an alignment from an attribute definition clause).
7927 -- At this stage, this can happen only for types (e.g. record types) for
7928 -- which the size is always non-static. We exclude generic types from
7929 -- consideration (since they have bogus sizes set within templates).
7931 elsif Id
= Attribute_Alignment
7932 and then Is_Type
(P_Entity
)
7933 and then (not Is_Generic_Type
(P_Entity
))
7934 and then Known_Alignment
(P_Entity
)
7936 Compile_Time_Known_Attribute
(N
, Alignment
(P_Entity
));
7939 -- If this is an access attribute that is known to fail accessibility
7940 -- check, rewrite accordingly.
7942 elsif Attribute_Name
(N
) = Name_Access
7943 and then Raises_Constraint_Error
(N
)
7946 Make_Raise_Program_Error
(Loc
,
7947 Reason
=> PE_Accessibility_Check_Failed
));
7948 Set_Etype
(N
, C_Type
);
7951 -- No other cases are foldable (they certainly aren't static, and at
7952 -- the moment we don't try to fold any cases other than the ones above).
7959 -- If either attribute or the prefix is Any_Type, then propagate
7960 -- Any_Type to the result and don't do anything else at all.
7962 if P_Type
= Any_Type
7963 or else (Present
(E1
) and then Etype
(E1
) = Any_Type
)
7964 or else (Present
(E2
) and then Etype
(E2
) = Any_Type
)
7966 Set_Etype
(N
, Any_Type
);
7970 -- Scalar subtype case. We have not yet enforced the static requirement
7971 -- of (RM 4.9(7)) and we don't intend to just yet, since there are cases
7972 -- of non-static attribute references (e.g. S'Digits for a non-static
7973 -- floating-point type, which we can compute at compile time).
7975 -- Note: this folding of non-static attributes is not simply a case of
7976 -- optimization. For many of the attributes affected, Gigi cannot handle
7977 -- the attribute and depends on the front end having folded them away.
7979 -- Note: although we don't require staticness at this stage, we do set
7980 -- the Static variable to record the staticness, for easy reference by
7981 -- those attributes where it matters (e.g. Succ and Pred), and also to
7982 -- be used to ensure that non-static folded things are not marked as
7983 -- being static (a check that is done right at the end).
7985 P_Root_Type
:= Root_Type
(P_Type
);
7986 P_Base_Type
:= Base_Type
(P_Type
);
7988 -- If the root type or base type is generic, then we cannot fold. This
7989 -- test is needed because subtypes of generic types are not always
7990 -- marked as being generic themselves (which seems odd???)
7992 if Is_Generic_Type
(P_Root_Type
)
7993 or else Is_Generic_Type
(P_Base_Type
)
7998 if Is_Scalar_Type
(P_Type
) then
7999 if not Is_Static_Subtype
(P_Type
) then
8001 Set_Is_Static_Expression
(N
, False);
8002 elsif not Is_OK_Static_Subtype
(P_Type
) then
8003 Set_Raises_Constraint_Error
(N
);
8006 -- Array case. We enforce the constrained requirement of (RM 4.9(7-8))
8007 -- since we can't do anything with unconstrained arrays. In addition,
8008 -- only the First, Last and Length attributes are possibly static.
8010 -- Atomic_Always_Lock_Free, Definite, Has_Access_Values,
8011 -- Has_Discriminants, Has_Tagged_Values, Lock_Free, Type_Class, and
8012 -- Unconstrained_Array are again exceptions, because they apply as well
8013 -- to unconstrained types.
8015 -- In addition Component_Size is an exception since it is possibly
8016 -- foldable, even though it is never static, and it does apply to
8017 -- unconstrained arrays. Furthermore, it is essential to fold this
8018 -- in the packed case, since otherwise the value will be incorrect.
8020 elsif Id
= Attribute_Atomic_Always_Lock_Free
or else
8021 Id
= Attribute_Definite
or else
8022 Id
= Attribute_Has_Access_Values
or else
8023 Id
= Attribute_Has_Discriminants
or else
8024 Id
= Attribute_Has_Tagged_Values
or else
8025 Id
= Attribute_Lock_Free
or else
8026 Id
= Attribute_Type_Class
or else
8027 Id
= Attribute_Unconstrained_Array
or else
8028 Id
= Attribute_Component_Size
8031 Set_Is_Static_Expression
(N
, False);
8033 elsif Id
/= Attribute_Max_Alignment_For_Allocation
then
8034 if not Is_Constrained
(P_Type
)
8035 or else (Id
/= Attribute_First
and then
8036 Id
/= Attribute_Last
and then
8037 Id
/= Attribute_Length
)
8043 -- The rules in (RM 4.9(7,8)) require a static array, but as in the
8044 -- scalar case, we hold off on enforcing staticness, since there are
8045 -- cases which we can fold at compile time even though they are not
8046 -- static (e.g. 'Length applied to a static index, even though other
8047 -- non-static indexes make the array type non-static). This is only
8048 -- an optimization, but it falls out essentially free, so why not.
8049 -- Again we compute the variable Static for easy reference later
8050 -- (note that no array attributes are static in Ada 83).
8052 -- We also need to set Static properly for subsequent legality checks
8053 -- which might otherwise accept non-static constants in contexts
8054 -- where they are not legal.
8057 Ada_Version
>= Ada_95
and then Statically_Denotes_Entity
(P
);
8058 Set_Is_Static_Expression
(N
, Static
);
8064 Nod
:= First_Index
(P_Type
);
8066 -- The expression is static if the array type is constrained
8067 -- by given bounds, and not by an initial expression. Constant
8068 -- strings are static in any case.
8070 if Root_Type
(P_Type
) /= Standard_String
then
8072 Static
and then not Is_Constr_Subt_For_U_Nominal
(P_Type
);
8073 Set_Is_Static_Expression
(N
, Static
);
8076 while Present
(Nod
) loop
8077 if not Is_Static_Subtype
(Etype
(Nod
)) then
8079 Set_Is_Static_Expression
(N
, False);
8081 elsif not Is_OK_Static_Subtype
(Etype
(Nod
)) then
8082 Set_Raises_Constraint_Error
(N
);
8084 Set_Is_Static_Expression
(N
, False);
8087 -- If however the index type is generic, or derived from
8088 -- one, attributes cannot be folded.
8090 if Is_Generic_Type
(Root_Type
(Etype
(Nod
)))
8091 and then Id
/= Attribute_Component_Size
8101 -- Check any expressions that are present. Note that these expressions,
8102 -- depending on the particular attribute type, are either part of the
8103 -- attribute designator, or they are arguments in a case where the
8104 -- attribute reference returns a function. In the latter case, the
8105 -- rule in (RM 4.9(22)) applies and in particular requires the type
8106 -- of the expressions to be scalar in order for the attribute to be
8107 -- considered to be static.
8115 while Present
(E
) loop
8117 -- If expression is not static, then the attribute reference
8118 -- result certainly cannot be static.
8120 if not Is_Static_Expression
(E
) then
8122 Set_Is_Static_Expression
(N
, False);
8125 if Raises_Constraint_Error
(E
) then
8126 Set_Raises_Constraint_Error
(N
);
8129 -- If the result is not known at compile time, or is not of
8130 -- a scalar type, then the result is definitely not static,
8131 -- so we can quit now.
8133 if not Compile_Time_Known_Value
(E
)
8134 or else not Is_Scalar_Type
(Etype
(E
))
8136 -- An odd special case, if this is a Pos attribute, this
8137 -- is where we need to apply a range check since it does
8138 -- not get done anywhere else.
8140 if Id
= Attribute_Pos
then
8141 if Is_Integer_Type
(Etype
(E
)) then
8142 Apply_Range_Check
(E
, Etype
(N
));
8149 -- If the expression raises a constraint error, then so does
8150 -- the attribute reference. We keep going in this case because
8151 -- we are still interested in whether the attribute reference
8152 -- is static even if it is not static.
8154 elsif Raises_Constraint_Error
(E
) then
8155 Set_Raises_Constraint_Error
(N
);
8161 if Raises_Constraint_Error
(Prefix
(N
)) then
8162 Set_Is_Static_Expression
(N
, False);
8167 -- Deal with the case of a static attribute reference that raises
8168 -- constraint error. The Raises_Constraint_Error flag will already
8169 -- have been set, and the Static flag shows whether the attribute
8170 -- reference is static. In any case we certainly can't fold such an
8171 -- attribute reference.
8173 -- Note that the rewriting of the attribute node with the constraint
8174 -- error node is essential in this case, because otherwise Gigi might
8175 -- blow up on one of the attributes it never expects to see.
8177 -- The constraint_error node must have the type imposed by the context,
8178 -- to avoid spurious errors in the enclosing expression.
8180 if Raises_Constraint_Error
(N
) then
8182 Make_Raise_Constraint_Error
(Sloc
(N
),
8183 Reason
=> CE_Range_Check_Failed
);
8184 Set_Etype
(CE_Node
, Etype
(N
));
8185 Set_Raises_Constraint_Error
(CE_Node
);
8187 Rewrite
(N
, Relocate_Node
(CE_Node
));
8188 Set_Raises_Constraint_Error
(N
, True);
8192 -- At this point we have a potentially foldable attribute reference.
8193 -- If Static is set, then the attribute reference definitely obeys
8194 -- the requirements in (RM 4.9(7,8,22)), and it definitely can be
8195 -- folded. If Static is not set, then the attribute may or may not
8196 -- be foldable, and the individual attribute processing routines
8197 -- test Static as required in cases where it makes a difference.
8199 -- In the case where Static is not set, we do know that all the
8200 -- expressions present are at least known at compile time (we assumed
8201 -- above that if this was not the case, then there was no hope of static
8202 -- evaluation). However, we did not require that the bounds of the
8203 -- prefix type be compile time known, let alone static). That's because
8204 -- there are many attributes that can be computed at compile time on
8205 -- non-static subtypes, even though such references are not static
8208 -- For VAX float, the root type is an IEEE type. So make sure to use the
8209 -- base type instead of the root-type for floating point attributes.
8213 -- Attributes related to Ada 2012 iterators; nothing to evaluate for
8216 when Attribute_Constant_Indexing
8217 | Attribute_Default_Iterator
8218 | Attribute_Implicit_Dereference
8219 | Attribute_Iterator_Element
8220 | Attribute_Iterable
8221 | Attribute_Variable_Indexing
8225 -- Internal attributes used to deal with Ada 2012 delayed aspects.
8226 -- These were already rejected by the parser. Thus they shouldn't
8229 when Internal_Attribute_Id
=>
8230 raise Program_Error
;
8236 when Attribute_Adjacent
=>
8240 (P_Base_Type
, Expr_Value_R
(E1
), Expr_Value_R
(E2
)),
8247 when Attribute_Aft
=>
8248 Fold_Uint
(N
, Aft_Value
(P_Type
), Static
);
8254 when Attribute_Alignment
=> Alignment_Block
: declare
8255 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
8258 -- Fold if alignment is set and not otherwise
8260 if Known_Alignment
(P_TypeA
) then
8261 Fold_Uint
(N
, Alignment
(P_TypeA
), Static
);
8263 end Alignment_Block
;
8265 -----------------------------
8266 -- Atomic_Always_Lock_Free --
8267 -----------------------------
8269 -- Atomic_Always_Lock_Free attribute is a Boolean, thus no need to fold
8272 when Attribute_Atomic_Always_Lock_Free
=> Atomic_Always_Lock_Free
:
8274 V
: constant Entity_Id
:=
8276 (Support_Atomic_Primitives_On_Target
8277 and then Support_Atomic_Primitives
(P_Type
));
8280 Rewrite
(N
, New_Occurrence_Of
(V
, Loc
));
8282 -- Analyze and resolve as boolean. Note that this attribute is a
8283 -- static attribute in GNAT.
8285 Analyze_And_Resolve
(N
, Standard_Boolean
);
8287 Set_Is_Static_Expression
(N
, True);
8288 end Atomic_Always_Lock_Free
;
8294 -- Bit can never be folded
8296 when Attribute_Bit
=>
8303 -- Body_version can never be static
8305 when Attribute_Body_Version
=>
8312 when Attribute_Ceiling
=>
8314 (N
, Eval_Fat
.Ceiling
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8316 --------------------
8317 -- Component_Size --
8318 --------------------
8320 when Attribute_Component_Size
=>
8321 if Known_Static_Component_Size
(P_Type
) then
8322 Fold_Uint
(N
, Component_Size
(P_Type
), Static
);
8329 when Attribute_Compose
=>
8332 Eval_Fat
.Compose
(P_Base_Type
, Expr_Value_R
(E1
), Expr_Value
(E2
)),
8339 -- Constrained is never folded for now, there may be cases that
8340 -- could be handled at compile time. To be looked at later.
8342 when Attribute_Constrained
=>
8344 -- The expander might fold it and set the static flag accordingly,
8345 -- but with expansion disabled (as in ASIS), it remains as an
8346 -- attribute reference, and this reference is not static.
8348 Set_Is_Static_Expression
(N
, False);
8354 when Attribute_Copy_Sign
=>
8358 (P_Base_Type
, Expr_Value_R
(E1
), Expr_Value_R
(E2
)),
8365 when Attribute_Definite
=>
8366 Rewrite
(N
, New_Occurrence_Of
(
8367 Boolean_Literals
(Is_Definite_Subtype
(P_Entity
)), Loc
));
8368 Analyze_And_Resolve
(N
, Standard_Boolean
);
8374 when Attribute_Delta
=>
8375 Fold_Ureal
(N
, Delta_Value
(P_Type
), True);
8381 when Attribute_Denorm
=>
8383 (N
, UI_From_Int
(Boolean'Pos (Has_Denormals
(P_Type
))), Static
);
8385 ---------------------
8386 -- Descriptor_Size --
8387 ---------------------
8389 when Attribute_Descriptor_Size
=>
8396 when Attribute_Digits
=>
8397 Fold_Uint
(N
, Digits_Value
(P_Type
), Static
);
8403 when Attribute_Emax
=>
8405 -- Ada 83 attribute is defined as (RM83 3.5.8)
8407 -- T'Emax = 4 * T'Mantissa
8409 Fold_Uint
(N
, 4 * Mantissa
, Static
);
8415 when Attribute_Enum_Rep
=> Enum_Rep
: declare
8419 -- The attribute appears in the form:
8421 -- Enum_Typ'Enum_Rep (Const)
8422 -- Enum_Typ'Enum_Rep (Enum_Lit)
8424 if Present
(E1
) then
8427 -- Otherwise the prefix denotes a constant or enumeration literal:
8430 -- Enum_Lit'Enum_Rep
8436 -- For an enumeration type with a non-standard representation use
8437 -- the Enumeration_Rep field of the proper constant. Note that this
8438 -- will not work for types Character/Wide_[Wide-]Character, since no
8439 -- real entities are created for the enumeration literals, but that
8440 -- does not matter since these two types do not have non-standard
8441 -- representations anyway.
8443 if Is_Enumeration_Type
(P_Type
)
8444 and then Has_Non_Standard_Rep
(P_Type
)
8446 Fold_Uint
(N
, Enumeration_Rep
(Expr_Value_E
(Val
)), Static
);
8448 -- For enumeration types with standard representations and all other
8449 -- cases (i.e. all integer and modular types), Enum_Rep is equivalent
8453 Fold_Uint
(N
, Expr_Value
(Val
), Static
);
8461 when Attribute_Enum_Val
=> Enum_Val
: declare
8465 -- We have something like Enum_Type'Enum_Val (23), so search for a
8466 -- corresponding value in the list of Enum_Rep values for the type.
8468 Lit
:= First_Literal
(P_Base_Type
);
8470 if Enumeration_Rep
(Lit
) = Expr_Value
(E1
) then
8471 Fold_Uint
(N
, Enumeration_Pos
(Lit
), Static
);
8478 Apply_Compile_Time_Constraint_Error
8479 (N
, "no representation value matches",
8480 CE_Range_Check_Failed
,
8481 Warn
=> not Static
);
8491 when Attribute_Epsilon
=>
8493 -- Ada 83 attribute is defined as (RM83 3.5.8)
8495 -- T'Epsilon = 2.0**(1 - T'Mantissa)
8497 Fold_Ureal
(N
, Ureal_2
** (1 - Mantissa
), True);
8503 when Attribute_Exponent
=>
8505 Eval_Fat
.Exponent
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8507 -----------------------
8508 -- Finalization_Size --
8509 -----------------------
8511 when Attribute_Finalization_Size
=>
8518 when Attribute_First
=>
8521 if Compile_Time_Known_Value
(Lo_Bound
) then
8522 if Is_Real_Type
(P_Type
) then
8523 Fold_Ureal
(N
, Expr_Value_R
(Lo_Bound
), Static
);
8525 Fold_Uint
(N
, Expr_Value
(Lo_Bound
), Static
);
8529 Check_Concurrent_Discriminant
(Lo_Bound
);
8536 when Attribute_First_Valid
=>
8537 if Has_Predicates
(P_Type
)
8538 and then Has_Static_Predicate
(P_Type
)
8541 FirstN
: constant Node_Id
:=
8542 First
(Static_Discrete_Predicate
(P_Type
));
8544 if Nkind
(FirstN
) = N_Range
then
8545 Fold_Uint
(N
, Expr_Value
(Low_Bound
(FirstN
)), Static
);
8547 Fold_Uint
(N
, Expr_Value
(FirstN
), Static
);
8553 Fold_Uint
(N
, Expr_Value
(Lo_Bound
), Static
);
8560 when Attribute_Fixed_Value
=>
8567 when Attribute_Floor
=>
8569 (N
, Eval_Fat
.Floor
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8575 when Attribute_Fore
=>
8576 if Compile_Time_Known_Bounds
(P_Type
) then
8577 Fold_Uint
(N
, UI_From_Int
(Fore_Value
), Static
);
8584 when Attribute_Fraction
=>
8586 (N
, Eval_Fat
.Fraction
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8588 -----------------------
8589 -- Has_Access_Values --
8590 -----------------------
8592 when Attribute_Has_Access_Values
=>
8593 Rewrite
(N
, New_Occurrence_Of
8594 (Boolean_Literals
(Has_Access_Values
(P_Root_Type
)), Loc
));
8595 Analyze_And_Resolve
(N
, Standard_Boolean
);
8597 -----------------------
8598 -- Has_Discriminants --
8599 -----------------------
8601 when Attribute_Has_Discriminants
=>
8602 Rewrite
(N
, New_Occurrence_Of
(
8603 Boolean_Literals
(Has_Discriminants
(P_Entity
)), Loc
));
8604 Analyze_And_Resolve
(N
, Standard_Boolean
);
8606 ----------------------
8607 -- Has_Same_Storage --
8608 ----------------------
8610 when Attribute_Has_Same_Storage
=>
8613 -----------------------
8614 -- Has_Tagged_Values --
8615 -----------------------
8617 when Attribute_Has_Tagged_Values
=>
8618 Rewrite
(N
, New_Occurrence_Of
8619 (Boolean_Literals
(Has_Tagged_Component
(P_Root_Type
)), Loc
));
8620 Analyze_And_Resolve
(N
, Standard_Boolean
);
8626 when Attribute_Identity
=>
8633 -- Image is a scalar attribute, but is never static, because it is
8634 -- not a static function (having a non-scalar argument (RM 4.9(22))
8635 -- However, we can constant-fold the image of an enumeration literal
8636 -- if names are available.
8638 when Attribute_Image
=>
8639 if Is_Entity_Name
(E1
)
8640 and then Ekind
(Entity
(E1
)) = E_Enumeration_Literal
8641 and then not Discard_Names
(First_Subtype
(Etype
(E1
)))
8642 and then not Global_Discard_Names
8645 Lit
: constant Entity_Id
:= Entity
(E1
);
8649 Get_Unqualified_Decoded_Name_String
(Chars
(Lit
));
8650 Set_Casing
(All_Upper_Case
);
8651 Store_String_Chars
(Name_Buffer
(1 .. Name_Len
));
8653 Rewrite
(N
, Make_String_Literal
(Loc
, Strval
=> Str
));
8654 Analyze_And_Resolve
(N
, Standard_String
);
8655 Set_Is_Static_Expression
(N
, False);
8663 -- We never try to fold Integer_Value (though perhaps we could???)
8665 when Attribute_Integer_Value
=>
8672 -- Invalid_Value is a scalar attribute that is never static, because
8673 -- the value is by design out of range.
8675 when Attribute_Invalid_Value
=>
8682 when Attribute_Large
=>
8684 -- For fixed-point, we use the identity:
8686 -- T'Large = (2.0**T'Mantissa - 1.0) * T'Small
8688 if Is_Fixed_Point_Type
(P_Type
) then
8690 Make_Op_Multiply
(Loc
,
8692 Make_Op_Subtract
(Loc
,
8696 Make_Real_Literal
(Loc
, Ureal_2
),
8698 Make_Attribute_Reference
(Loc
,
8700 Attribute_Name
=> Name_Mantissa
)),
8701 Right_Opnd
=> Make_Real_Literal
(Loc
, Ureal_1
)),
8704 Make_Real_Literal
(Loc
, Small_Value
(Entity
(P
)))));
8706 Analyze_And_Resolve
(N
, C_Type
);
8708 -- Floating-point (Ada 83 compatibility)
8711 -- Ada 83 attribute is defined as (RM83 3.5.8)
8713 -- T'Large = 2.0**T'Emax * (1.0 - 2.0**(-T'Mantissa))
8717 -- T'Emax = 4 * T'Mantissa
8721 Ureal_2
** (4 * Mantissa
) * (Ureal_1
- Ureal_2
** (-Mantissa
)),
8729 when Attribute_Lock_Free
=> Lock_Free
: declare
8730 V
: constant Entity_Id
:= Boolean_Literals
(Uses_Lock_Free
(P_Type
));
8733 Rewrite
(N
, New_Occurrence_Of
(V
, Loc
));
8735 -- Analyze and resolve as boolean. Note that this attribute is a
8736 -- static attribute in GNAT.
8738 Analyze_And_Resolve
(N
, Standard_Boolean
);
8740 Set_Is_Static_Expression
(N
, True);
8747 when Attribute_Last
=>
8750 if Compile_Time_Known_Value
(Hi_Bound
) then
8751 if Is_Real_Type
(P_Type
) then
8752 Fold_Ureal
(N
, Expr_Value_R
(Hi_Bound
), Static
);
8754 Fold_Uint
(N
, Expr_Value
(Hi_Bound
), Static
);
8758 Check_Concurrent_Discriminant
(Hi_Bound
);
8765 when Attribute_Last_Valid
=>
8766 if Has_Predicates
(P_Type
)
8767 and then Has_Static_Predicate
(P_Type
)
8770 LastN
: constant Node_Id
:=
8771 Last
(Static_Discrete_Predicate
(P_Type
));
8773 if Nkind
(LastN
) = N_Range
then
8774 Fold_Uint
(N
, Expr_Value
(High_Bound
(LastN
)), Static
);
8776 Fold_Uint
(N
, Expr_Value
(LastN
), Static
);
8782 Fold_Uint
(N
, Expr_Value
(Hi_Bound
), Static
);
8789 when Attribute_Leading_Part
=>
8792 Eval_Fat
.Leading_Part
8793 (P_Base_Type
, Expr_Value_R
(E1
), Expr_Value
(E2
)),
8800 when Attribute_Length
=> Length
: declare
8804 -- If any index type is a formal type, or derived from one, the
8805 -- bounds are not static. Treating them as static can produce
8806 -- spurious warnings or improper constant folding.
8808 Ind
:= First_Index
(P_Type
);
8809 while Present
(Ind
) loop
8810 if Is_Generic_Type
(Root_Type
(Etype
(Ind
))) then
8819 -- For two compile time values, we can compute length
8821 if Compile_Time_Known_Value
(Lo_Bound
)
8822 and then Compile_Time_Known_Value
(Hi_Bound
)
8825 UI_Max
(0, 1 + (Expr_Value
(Hi_Bound
) - Expr_Value
(Lo_Bound
))),
8829 -- One more case is where Hi_Bound and Lo_Bound are compile-time
8830 -- comparable, and we can figure out the difference between them.
8833 Diff
: aliased Uint
;
8837 Compile_Time_Compare
8838 (Lo_Bound
, Hi_Bound
, Diff
'Access, Assume_Valid
=> False)
8841 Fold_Uint
(N
, Uint_1
, Static
);
8844 Fold_Uint
(N
, Uint_0
, Static
);
8847 if Diff
/= No_Uint
then
8848 Fold_Uint
(N
, Diff
+ 1, Static
);
8861 -- Loop_Entry acts as an alias of a constant initialized to the prefix
8862 -- of the said attribute at the point of entry into the related loop. As
8863 -- such, the attribute reference does not need to be evaluated because
8864 -- the prefix is the one that is evaluted.
8866 when Attribute_Loop_Entry
=>
8873 when Attribute_Machine
=>
8877 (P_Base_Type
, Expr_Value_R
(E1
), Eval_Fat
.Round
, N
),
8884 when Attribute_Machine_Emax
=>
8885 Fold_Uint
(N
, Machine_Emax_Value
(P_Type
), Static
);
8891 when Attribute_Machine_Emin
=>
8892 Fold_Uint
(N
, Machine_Emin_Value
(P_Type
), Static
);
8894 ----------------------
8895 -- Machine_Mantissa --
8896 ----------------------
8898 when Attribute_Machine_Mantissa
=>
8899 Fold_Uint
(N
, Machine_Mantissa_Value
(P_Type
), Static
);
8901 -----------------------
8902 -- Machine_Overflows --
8903 -----------------------
8905 when Attribute_Machine_Overflows
=>
8907 -- Always true for fixed-point
8909 if Is_Fixed_Point_Type
(P_Type
) then
8910 Fold_Uint
(N
, True_Value
, Static
);
8912 -- Floating point case
8916 UI_From_Int
(Boolean'Pos (Machine_Overflows_On_Target
)),
8924 when Attribute_Machine_Radix
=>
8925 if Is_Fixed_Point_Type
(P_Type
) then
8926 if Is_Decimal_Fixed_Point_Type
(P_Type
)
8927 and then Machine_Radix_10
(P_Type
)
8929 Fold_Uint
(N
, Uint_10
, Static
);
8931 Fold_Uint
(N
, Uint_2
, Static
);
8934 -- All floating-point type always have radix 2
8937 Fold_Uint
(N
, Uint_2
, Static
);
8940 ----------------------
8941 -- Machine_Rounding --
8942 ----------------------
8944 -- Note: for the folding case, it is fine to treat Machine_Rounding
8945 -- exactly the same way as Rounding, since this is one of the allowed
8946 -- behaviors, and performance is not an issue here. It might be a bit
8947 -- better to give the same result as it would give at run time, even
8948 -- though the non-determinism is certainly permitted.
8950 when Attribute_Machine_Rounding
=>
8952 (N
, Eval_Fat
.Rounding
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8954 --------------------
8955 -- Machine_Rounds --
8956 --------------------
8958 when Attribute_Machine_Rounds
=>
8960 -- Always False for fixed-point
8962 if Is_Fixed_Point_Type
(P_Type
) then
8963 Fold_Uint
(N
, False_Value
, Static
);
8965 -- Else yield proper floating-point result
8969 (N
, UI_From_Int
(Boolean'Pos (Machine_Rounds_On_Target
)),
8977 -- Note: Machine_Size is identical to Object_Size
8979 when Attribute_Machine_Size
=> Machine_Size
: declare
8980 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
8983 if Known_Esize
(P_TypeA
) then
8984 Fold_Uint
(N
, Esize
(P_TypeA
), Static
);
8992 when Attribute_Mantissa
=>
8994 -- Fixed-point mantissa
8996 if Is_Fixed_Point_Type
(P_Type
) then
8998 -- Compile time foldable case
9000 if Compile_Time_Known_Value
(Type_Low_Bound
(P_Type
))
9002 Compile_Time_Known_Value
(Type_High_Bound
(P_Type
))
9004 -- The calculation of the obsolete Ada 83 attribute Mantissa
9005 -- is annoying, because of AI00143, quoted here:
9007 -- !question 84-01-10
9009 -- Consider the model numbers for F:
9011 -- type F is delta 1.0 range -7.0 .. 8.0;
9013 -- The wording requires that F'MANTISSA be the SMALLEST
9014 -- integer number for which each bound of the specified
9015 -- range is either a model number or lies at most small
9016 -- distant from a model number. This means F'MANTISSA
9017 -- is required to be 3 since the range -7.0 .. 7.0 fits
9018 -- in 3 signed bits, and 8 is "at most" 1.0 from a model
9019 -- number, namely, 7. Is this analysis correct? Note that
9020 -- this implies the upper bound of the range is not
9021 -- represented as a model number.
9023 -- !response 84-03-17
9025 -- The analysis is correct. The upper and lower bounds for
9026 -- a fixed point type can lie outside the range of model
9037 LBound
:= Expr_Value_R
(Type_Low_Bound
(P_Type
));
9038 UBound
:= Expr_Value_R
(Type_High_Bound
(P_Type
));
9039 Bound
:= UR_Max
(UR_Abs
(LBound
), UR_Abs
(UBound
));
9040 Max_Man
:= UR_Trunc
(Bound
/ Small_Value
(P_Type
));
9042 -- If the Bound is exactly a model number, i.e. a multiple
9043 -- of Small, then we back it off by one to get the integer
9044 -- value that must be representable.
9046 if Small_Value
(P_Type
) * Max_Man
= Bound
then
9047 Max_Man
:= Max_Man
- 1;
9050 -- Now find corresponding size = Mantissa value
9053 while 2 ** Siz
< Max_Man
loop
9057 Fold_Uint
(N
, Siz
, Static
);
9061 -- The case of dynamic bounds cannot be evaluated at compile
9062 -- time. Instead we use a runtime routine (see Exp_Attr).
9067 -- Floating-point Mantissa
9070 Fold_Uint
(N
, Mantissa
, Static
);
9077 when Attribute_Max
=>
9078 if Is_Real_Type
(P_Type
) then
9080 (N
, UR_Max
(Expr_Value_R
(E1
), Expr_Value_R
(E2
)), Static
);
9082 Fold_Uint
(N
, UI_Max
(Expr_Value
(E1
), Expr_Value
(E2
)), Static
);
9085 ----------------------------------
9086 -- Max_Alignment_For_Allocation --
9087 ----------------------------------
9089 -- Max_Alignment_For_Allocation is usually the Alignment. However,
9090 -- arrays are allocated with dope, so we need to take into account both
9091 -- the alignment of the array, which comes from the component alignment,
9092 -- and the alignment of the dope. Also, if the alignment is unknown, we
9093 -- use the max (it's OK to be pessimistic).
9095 when Attribute_Max_Alignment_For_Allocation
=> Max_Align
: declare
9096 A
: Uint
:= UI_From_Int
(Ttypes
.Maximum_Alignment
);
9098 if Known_Alignment
(P_Type
)
9099 and then (not Is_Array_Type
(P_Type
) or else Alignment
(P_Type
) > A
)
9101 A
:= Alignment
(P_Type
);
9104 Fold_Uint
(N
, A
, Static
);
9107 ----------------------------------
9108 -- Max_Size_In_Storage_Elements --
9109 ----------------------------------
9111 -- Max_Size_In_Storage_Elements is simply the Size rounded up to a
9112 -- Storage_Unit boundary. We can fold any cases for which the size
9113 -- is known by the front end.
9115 when Attribute_Max_Size_In_Storage_Elements
=>
9116 if Known_Esize
(P_Type
) then
9118 (Esize
(P_Type
) + System_Storage_Unit
- 1) /
9119 System_Storage_Unit
,
9123 --------------------
9124 -- Mechanism_Code --
9125 --------------------
9127 when Attribute_Mechanism_Code
=> Mechanism_Code
: declare
9129 Mech
: Mechanism_Type
;
9134 Mech
:= Mechanism
(P_Entity
);
9137 Val
:= UI_To_Int
(Expr_Value
(E1
));
9139 Formal
:= First_Formal
(P_Entity
);
9140 for J
in 1 .. Val
- 1 loop
9141 Next_Formal
(Formal
);
9144 Mech
:= Mechanism
(Formal
);
9148 Fold_Uint
(N
, UI_From_Int
(Int
(-Mech
)), Static
);
9156 when Attribute_Min
=>
9157 if Is_Real_Type
(P_Type
) then
9159 (N
, UR_Min
(Expr_Value_R
(E1
), Expr_Value_R
(E2
)), Static
);
9162 (N
, UI_Min
(Expr_Value
(E1
), Expr_Value
(E2
)), Static
);
9169 when Attribute_Mod
=>
9171 (N
, UI_Mod
(Expr_Value
(E1
), Modulus
(P_Base_Type
)), Static
);
9177 when Attribute_Model
=>
9179 (N
, Eval_Fat
.Model
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
9185 when Attribute_Model_Emin
=>
9186 Fold_Uint
(N
, Model_Emin_Value
(P_Base_Type
), Static
);
9192 when Attribute_Model_Epsilon
=>
9193 Fold_Ureal
(N
, Model_Epsilon_Value
(P_Base_Type
), Static
);
9195 --------------------
9196 -- Model_Mantissa --
9197 --------------------
9199 when Attribute_Model_Mantissa
=>
9200 Fold_Uint
(N
, Model_Mantissa_Value
(P_Base_Type
), Static
);
9206 when Attribute_Model_Small
=>
9207 Fold_Ureal
(N
, Model_Small_Value
(P_Base_Type
), Static
);
9213 when Attribute_Modulus
=>
9214 Fold_Uint
(N
, Modulus
(P_Type
), Static
);
9216 --------------------
9217 -- Null_Parameter --
9218 --------------------
9220 -- Cannot fold, we know the value sort of, but the whole point is
9221 -- that there is no way to talk about this imaginary value except
9222 -- by using the attribute, so we leave it the way it is.
9224 when Attribute_Null_Parameter
=>
9231 -- The Object_Size attribute for a type returns the Esize of the
9232 -- type and can be folded if this value is known.
9234 when Attribute_Object_Size
=> Object_Size
: declare
9235 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
9238 if Known_Esize
(P_TypeA
) then
9239 Fold_Uint
(N
, Esize
(P_TypeA
), Static
);
9243 ----------------------
9244 -- Overlaps_Storage --
9245 ----------------------
9247 when Attribute_Overlaps_Storage
=>
9250 -------------------------
9251 -- Passed_By_Reference --
9252 -------------------------
9254 -- Scalar types are never passed by reference
9256 when Attribute_Passed_By_Reference
=>
9257 Fold_Uint
(N
, False_Value
, Static
);
9263 when Attribute_Pos
=>
9264 Fold_Uint
(N
, Expr_Value
(E1
), Static
);
9270 when Attribute_Pred
=>
9272 -- Floating-point case
9274 if Is_Floating_Point_Type
(P_Type
) then
9276 (N
, Eval_Fat
.Pred
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
9280 elsif Is_Fixed_Point_Type
(P_Type
) then
9282 (N
, Expr_Value_R
(E1
) - Small_Value
(P_Type
), True);
9284 -- Modular integer case (wraps)
9286 elsif Is_Modular_Integer_Type
(P_Type
) then
9287 Fold_Uint
(N
, (Expr_Value
(E1
) - 1) mod Modulus
(P_Type
), Static
);
9289 -- Other scalar cases
9292 pragma Assert
(Is_Scalar_Type
(P_Type
));
9294 if Is_Enumeration_Type
(P_Type
)
9295 and then Expr_Value
(E1
) =
9296 Expr_Value
(Type_Low_Bound
(P_Base_Type
))
9298 Apply_Compile_Time_Constraint_Error
9299 (N
, "Pred of `&''First`",
9300 CE_Overflow_Check_Failed
,
9302 Warn
=> not Static
);
9308 Fold_Uint
(N
, Expr_Value
(E1
) - 1, Static
);
9315 -- No processing required, because by this stage, Range has been
9316 -- replaced by First .. Last, so this branch can never be taken.
9318 when Attribute_Range
=>
9319 raise Program_Error
;
9325 when Attribute_Range_Length
=> Range_Length
: declare
9326 Diff
: aliased Uint
;
9331 -- Can fold if both bounds are compile time known
9333 if Compile_Time_Known_Value
(Hi_Bound
)
9334 and then Compile_Time_Known_Value
(Lo_Bound
)
9338 (0, Expr_Value
(Hi_Bound
) - Expr_Value
(Lo_Bound
) + 1),
9342 -- One more case is where Hi_Bound and Lo_Bound are compile-time
9343 -- comparable, and we can figure out the difference between them.
9345 case Compile_Time_Compare
9346 (Lo_Bound
, Hi_Bound
, Diff
'Access, Assume_Valid
=> False)
9349 Fold_Uint
(N
, Uint_1
, Static
);
9352 Fold_Uint
(N
, Uint_0
, Static
);
9355 if Diff
/= No_Uint
then
9356 Fold_Uint
(N
, Diff
+ 1, Static
);
9368 when Attribute_Ref
=>
9369 Fold_Uint
(N
, Expr_Value
(E1
), Static
);
9375 when Attribute_Remainder
=> Remainder
: declare
9376 X
: constant Ureal
:= Expr_Value_R
(E1
);
9377 Y
: constant Ureal
:= Expr_Value_R
(E2
);
9380 if UR_Is_Zero
(Y
) then
9381 Apply_Compile_Time_Constraint_Error
9382 (N
, "division by zero in Remainder",
9383 CE_Overflow_Check_Failed
,
9384 Warn
=> not Static
);
9390 Fold_Ureal
(N
, Eval_Fat
.Remainder
(P_Base_Type
, X
, Y
), Static
);
9397 when Attribute_Restriction_Set
=>
9398 Rewrite
(N
, New_Occurrence_Of
(Standard_False
, Loc
));
9399 Set_Is_Static_Expression
(N
);
9405 when Attribute_Round
=> Round
: declare
9410 -- First we get the (exact result) in units of small
9412 Sr
:= Expr_Value_R
(E1
) / Small_Value
(C_Type
);
9414 -- Now round that exactly to an integer
9416 Si
:= UR_To_Uint
(Sr
);
9418 -- Finally the result is obtained by converting back to real
9420 Fold_Ureal
(N
, Si
* Small_Value
(C_Type
), Static
);
9427 when Attribute_Rounding
=>
9429 (N
, Eval_Fat
.Rounding
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
9435 when Attribute_Safe_Emax
=>
9436 Fold_Uint
(N
, Safe_Emax_Value
(P_Type
), Static
);
9442 when Attribute_Safe_First
=>
9443 Fold_Ureal
(N
, Safe_First_Value
(P_Type
), Static
);
9449 when Attribute_Safe_Large
=>
9450 if Is_Fixed_Point_Type
(P_Type
) then
9452 (N
, Expr_Value_R
(Type_High_Bound
(P_Base_Type
)), Static
);
9454 Fold_Ureal
(N
, Safe_Last_Value
(P_Type
), Static
);
9461 when Attribute_Safe_Last
=>
9462 Fold_Ureal
(N
, Safe_Last_Value
(P_Type
), Static
);
9468 when Attribute_Safe_Small
=>
9470 -- In Ada 95, the old Ada 83 attribute Safe_Small is redundant
9471 -- for fixed-point, since is the same as Small, but we implement
9472 -- it for backwards compatibility.
9474 if Is_Fixed_Point_Type
(P_Type
) then
9475 Fold_Ureal
(N
, Small_Value
(P_Type
), Static
);
9477 -- Ada 83 Safe_Small for floating-point cases
9480 Fold_Ureal
(N
, Model_Small_Value
(P_Type
), Static
);
9487 when Attribute_Scale
=>
9488 Fold_Uint
(N
, Scale_Value
(P_Type
), Static
);
9494 when Attribute_Scaling
=>
9498 (P_Base_Type
, Expr_Value_R
(E1
), Expr_Value
(E2
)),
9505 when Attribute_Signed_Zeros
=>
9507 (N
, UI_From_Int
(Boolean'Pos (Has_Signed_Zeros
(P_Type
))), Static
);
9513 -- Size attribute returns the RM size. All scalar types can be folded,
9514 -- as well as any types for which the size is known by the front end,
9515 -- including any type for which a size attribute is specified. This is
9516 -- one of the places where it is annoying that a size of zero means two
9517 -- things (zero size for scalars, unspecified size for non-scalars).
9520 | Attribute_VADS_Size
9523 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
9526 if Is_Scalar_Type
(P_TypeA
)
9527 or else RM_Size
(P_TypeA
) /= Uint_0
9531 if Id
= Attribute_VADS_Size
or else Use_VADS_Size
then
9533 S
: constant Node_Id
:= Size_Clause
(P_TypeA
);
9536 -- If a size clause applies, then use the size from it.
9537 -- This is one of the rare cases where we can use the
9538 -- Size_Clause field for a subtype when Has_Size_Clause
9539 -- is False. Consider:
9541 -- type x is range 1 .. 64;
9542 -- for x'size use 12;
9543 -- subtype y is x range 0 .. 3;
9545 -- Here y has a size clause inherited from x, but
9546 -- normally it does not apply, and y'size is 2. However,
9547 -- y'VADS_Size is indeed 12 and not 2.
9550 and then Is_OK_Static_Expression
(Expression
(S
))
9552 Fold_Uint
(N
, Expr_Value
(Expression
(S
)), Static
);
9554 -- If no size is specified, then we simply use the object
9555 -- size in the VADS_Size case (e.g. Natural'Size is equal
9556 -- to Integer'Size, not one less).
9559 Fold_Uint
(N
, Esize
(P_TypeA
), Static
);
9563 -- Normal case (Size) in which case we want the RM_Size
9566 Fold_Uint
(N
, RM_Size
(P_TypeA
), Static
);
9575 when Attribute_Small
=>
9577 -- The floating-point case is present only for Ada 83 compatibility.
9578 -- Note that strictly this is an illegal addition, since we are
9579 -- extending an Ada 95 defined attribute, but we anticipate an
9580 -- ARG ruling that will permit this.
9582 if Is_Floating_Point_Type
(P_Type
) then
9584 -- Ada 83 attribute is defined as (RM83 3.5.8)
9586 -- T'Small = 2.0**(-T'Emax - 1)
9590 -- T'Emax = 4 * T'Mantissa
9592 Fold_Ureal
(N
, Ureal_2
** ((-(4 * Mantissa
)) - 1), Static
);
9594 -- Normal Ada 95 fixed-point case
9597 Fold_Ureal
(N
, Small_Value
(P_Type
), True);
9604 when Attribute_Stream_Size
=>
9611 when Attribute_Succ
=>
9612 -- Floating-point case
9614 if Is_Floating_Point_Type
(P_Type
) then
9616 (N
, Eval_Fat
.Succ
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
9620 elsif Is_Fixed_Point_Type
(P_Type
) then
9621 Fold_Ureal
(N
, Expr_Value_R
(E1
) + Small_Value
(P_Type
), Static
);
9623 -- Modular integer case (wraps)
9625 elsif Is_Modular_Integer_Type
(P_Type
) then
9626 Fold_Uint
(N
, (Expr_Value
(E1
) + 1) mod Modulus
(P_Type
), Static
);
9628 -- Other scalar cases
9631 pragma Assert
(Is_Scalar_Type
(P_Type
));
9633 if Is_Enumeration_Type
(P_Type
)
9634 and then Expr_Value
(E1
) =
9635 Expr_Value
(Type_High_Bound
(P_Base_Type
))
9637 Apply_Compile_Time_Constraint_Error
9638 (N
, "Succ of `&''Last`",
9639 CE_Overflow_Check_Failed
,
9641 Warn
=> not Static
);
9646 Fold_Uint
(N
, Expr_Value
(E1
) + 1, Static
);
9654 when Attribute_Truncation
=>
9657 Eval_Fat
.Truncation
(P_Base_Type
, Expr_Value_R
(E1
)),
9664 when Attribute_Type_Class
=> Type_Class
: declare
9665 Typ
: constant Entity_Id
:= Underlying_Type
(P_Base_Type
);
9669 if Is_Descendant_Of_Address
(Typ
) then
9670 Id
:= RE_Type_Class_Address
;
9672 elsif Is_Enumeration_Type
(Typ
) then
9673 Id
:= RE_Type_Class_Enumeration
;
9675 elsif Is_Integer_Type
(Typ
) then
9676 Id
:= RE_Type_Class_Integer
;
9678 elsif Is_Fixed_Point_Type
(Typ
) then
9679 Id
:= RE_Type_Class_Fixed_Point
;
9681 elsif Is_Floating_Point_Type
(Typ
) then
9682 Id
:= RE_Type_Class_Floating_Point
;
9684 elsif Is_Array_Type
(Typ
) then
9685 Id
:= RE_Type_Class_Array
;
9687 elsif Is_Record_Type
(Typ
) then
9688 Id
:= RE_Type_Class_Record
;
9690 elsif Is_Access_Type
(Typ
) then
9691 Id
:= RE_Type_Class_Access
;
9693 elsif Is_Task_Type
(Typ
) then
9694 Id
:= RE_Type_Class_Task
;
9696 -- We treat protected types like task types. It would make more
9697 -- sense to have another enumeration value, but after all the
9698 -- whole point of this feature is to be exactly DEC compatible,
9699 -- and changing the type Type_Class would not meet this requirement.
9701 elsif Is_Protected_Type
(Typ
) then
9702 Id
:= RE_Type_Class_Task
;
9704 -- Not clear if there are any other possibilities, but if there
9705 -- are, then we will treat them as the address case.
9708 Id
:= RE_Type_Class_Address
;
9711 Rewrite
(N
, New_Occurrence_Of
(RTE
(Id
), Loc
));
9714 -----------------------
9715 -- Unbiased_Rounding --
9716 -----------------------
9718 when Attribute_Unbiased_Rounding
=>
9721 Eval_Fat
.Unbiased_Rounding
(P_Base_Type
, Expr_Value_R
(E1
)),
9724 -------------------------
9725 -- Unconstrained_Array --
9726 -------------------------
9728 when Attribute_Unconstrained_Array
=> Unconstrained_Array
: declare
9729 Typ
: constant Entity_Id
:= Underlying_Type
(P_Type
);
9732 Rewrite
(N
, New_Occurrence_Of
(
9734 Is_Array_Type
(P_Type
)
9735 and then not Is_Constrained
(Typ
)), Loc
));
9737 -- Analyze and resolve as boolean, note that this attribute is
9738 -- a static attribute in GNAT.
9740 Analyze_And_Resolve
(N
, Standard_Boolean
);
9742 Set_Is_Static_Expression
(N
, True);
9743 end Unconstrained_Array
;
9745 -- Attribute Update is never static
9747 when Attribute_Update
=>
9754 -- Processing is shared with Size
9760 when Attribute_Val
=>
9761 if Expr_Value
(E1
) < Expr_Value
(Type_Low_Bound
(P_Base_Type
))
9763 Expr_Value
(E1
) > Expr_Value
(Type_High_Bound
(P_Base_Type
))
9765 Apply_Compile_Time_Constraint_Error
9766 (N
, "Val expression out of range",
9767 CE_Range_Check_Failed
,
9768 Warn
=> not Static
);
9774 Fold_Uint
(N
, Expr_Value
(E1
), Static
);
9781 -- The Value_Size attribute for a type returns the RM size of the type.
9782 -- This an always be folded for scalar types, and can also be folded for
9783 -- non-scalar types if the size is set. This is one of the places where
9784 -- it is annoying that a size of zero means two things!
9786 when Attribute_Value_Size
=> Value_Size
: declare
9787 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
9790 if Is_Scalar_Type
(P_TypeA
) or else RM_Size
(P_TypeA
) /= Uint_0
then
9791 Fold_Uint
(N
, RM_Size
(P_TypeA
), Static
);
9799 -- Version can never be static
9801 when Attribute_Version
=>
9808 -- Wide_Image is a scalar attribute, but is never static, because it
9809 -- is not a static function (having a non-scalar argument (RM 4.9(22))
9811 when Attribute_Wide_Image
=>
9814 ---------------------
9815 -- Wide_Wide_Image --
9816 ---------------------
9818 -- Wide_Wide_Image is a scalar attribute but is never static, because it
9819 -- is not a static function (having a non-scalar argument (RM 4.9(22)).
9821 when Attribute_Wide_Wide_Image
=>
9824 ---------------------
9825 -- Wide_Wide_Width --
9826 ---------------------
9828 -- Processing for Wide_Wide_Width is combined with Width
9834 -- Processing for Wide_Width is combined with Width
9840 -- This processing also handles the case of Wide_[Wide_]Width
9842 when Attribute_Width
9843 | Attribute_Wide_Width
9844 | Attribute_Wide_Wide_Width
9846 if Compile_Time_Known_Bounds
(P_Type
) then
9848 -- Floating-point types
9850 if Is_Floating_Point_Type
(P_Type
) then
9852 -- Width is zero for a null range (RM 3.5 (38))
9854 if Expr_Value_R
(Type_High_Bound
(P_Type
)) <
9855 Expr_Value_R
(Type_Low_Bound
(P_Type
))
9857 Fold_Uint
(N
, Uint_0
, Static
);
9860 -- For floating-point, we have +N.dddE+nnn where length
9861 -- of ddd is determined by type'Digits - 1, but is one
9862 -- if Digits is one (RM 3.5 (33)).
9864 -- nnn is set to 2 for Short_Float and Float (32 bit
9865 -- floats), and 3 for Long_Float and Long_Long_Float.
9866 -- For machines where Long_Long_Float is the IEEE
9867 -- extended precision type, the exponent takes 4 digits.
9871 Int
'Max (2, UI_To_Int
(Digits_Value
(P_Type
)));
9874 if Esize
(P_Type
) <= 32 then
9876 elsif Esize
(P_Type
) = 64 then
9882 Fold_Uint
(N
, UI_From_Int
(Len
), Static
);
9886 -- Fixed-point types
9888 elsif Is_Fixed_Point_Type
(P_Type
) then
9890 -- Width is zero for a null range (RM 3.5 (38))
9892 if Expr_Value
(Type_High_Bound
(P_Type
)) <
9893 Expr_Value
(Type_Low_Bound
(P_Type
))
9895 Fold_Uint
(N
, Uint_0
, Static
);
9897 -- The non-null case depends on the specific real type
9900 -- For fixed-point type width is Fore + 1 + Aft (RM 3.5(34))
9903 (N
, UI_From_Int
(Fore_Value
+ 1) + Aft_Value
(P_Type
),
9911 R
: constant Entity_Id
:= Root_Type
(P_Type
);
9912 Lo
: constant Uint
:= Expr_Value
(Type_Low_Bound
(P_Type
));
9913 Hi
: constant Uint
:= Expr_Value
(Type_High_Bound
(P_Type
));
9926 -- Width for types derived from Standard.Character
9927 -- and Standard.Wide_[Wide_]Character.
9929 elsif Is_Standard_Character_Type
(P_Type
) then
9932 -- Set W larger if needed
9934 for J
in UI_To_Int
(Lo
) .. UI_To_Int
(Hi
) loop
9936 -- All wide characters look like Hex_hhhhhhhh
9940 -- No need to compute this more than once
9945 C
:= Character'Val (J
);
9947 -- Test for all cases where Character'Image
9948 -- yields an image that is longer than three
9949 -- characters. First the cases of Reserved_xxx
9950 -- names (length = 12).
10027 when Space
.. Tilde
10028 | No_Break_Space
.. LC_Y_Diaeresis
10030 -- Special case of soft hyphen in Ada 2005
10032 if C
= Character'Val (16#AD#
)
10033 and then Ada_Version
>= Ada_2005
10041 W
:= Int
'Max (W
, Wt
);
10045 -- Width for types derived from Standard.Boolean
10047 elsif R
= Standard_Boolean
then
10054 -- Width for integer types
10056 elsif Is_Integer_Type
(P_Type
) then
10057 T
:= UI_Max
(abs Lo
, abs Hi
);
10065 -- User declared enum type with discard names
10067 elsif Discard_Names
(R
) then
10069 -- If range is null, result is zero, that has already
10070 -- been dealt with, so what we need is the power of ten
10071 -- that accommodates the Pos of the largest value, which
10072 -- is the high bound of the range + one for the space.
10081 -- Only remaining possibility is user declared enum type
10082 -- with normal case of Discard_Names not active.
10085 pragma Assert
(Is_Enumeration_Type
(P_Type
));
10088 L
:= First_Literal
(P_Type
);
10089 while Present
(L
) loop
10091 -- Only pay attention to in range characters
10093 if Lo
<= Enumeration_Pos
(L
)
10094 and then Enumeration_Pos
(L
) <= Hi
10096 -- For Width case, use decoded name
10098 if Id
= Attribute_Width
then
10099 Get_Decoded_Name_String
(Chars
(L
));
10100 Wt
:= Nat
(Name_Len
);
10102 -- For Wide_[Wide_]Width, use encoded name, and
10103 -- then adjust for the encoding.
10106 Get_Name_String
(Chars
(L
));
10108 -- Character literals are always of length 3
10110 if Name_Buffer
(1) = 'Q' then
10113 -- Otherwise loop to adjust for upper/wide chars
10116 Wt
:= Nat
(Name_Len
);
10118 for J
in 1 .. Name_Len
loop
10119 if Name_Buffer
(J
) = 'U' then
10121 elsif Name_Buffer
(J
) = 'W' then
10128 W
:= Int
'Max (W
, Wt
);
10135 Fold_Uint
(N
, UI_From_Int
(W
), Static
);
10140 -- The following attributes denote functions that cannot be folded
10142 when Attribute_From_Any
10144 | Attribute_TypeCode
10148 -- The following attributes can never be folded, and furthermore we
10149 -- should not even have entered the case statement for any of these.
10150 -- Note that in some cases, the values have already been folded as
10151 -- a result of the processing in Analyze_Attribute or earlier in
10154 when Attribute_Abort_Signal
10156 | Attribute_Address
10157 | Attribute_Address_Size
10158 | Attribute_Asm_Input
10159 | Attribute_Asm_Output
10161 | Attribute_Bit_Order
10162 | Attribute_Bit_Position
10163 | Attribute_Callable
10166 | Attribute_Code_Address
10167 | Attribute_Compiler_Version
10169 | Attribute_Default_Bit_Order
10170 | Attribute_Default_Scalar_Storage_Order
10172 | Attribute_Elaborated
10173 | Attribute_Elab_Body
10174 | Attribute_Elab_Spec
10175 | Attribute_Elab_Subp_Body
10176 | Attribute_Enabled
10177 | Attribute_External_Tag
10178 | Attribute_Fast_Math
10179 | Attribute_First_Bit
10182 | Attribute_Last_Bit
10183 | Attribute_Library_Level
10184 | Attribute_Maximum_Alignment
10187 | Attribute_Partition_ID
10188 | Attribute_Pool_Address
10189 | Attribute_Position
10190 | Attribute_Priority
10193 | Attribute_Scalar_Storage_Order
10194 | Attribute_Simple_Storage_Pool
10195 | Attribute_Storage_Pool
10196 | Attribute_Storage_Size
10197 | Attribute_Storage_Unit
10198 | Attribute_Stub_Type
10199 | Attribute_System_Allocator_Alignment
10201 | Attribute_Target_Name
10202 | Attribute_Terminated
10203 | Attribute_To_Address
10204 | Attribute_Type_Key
10205 | Attribute_Unchecked_Access
10206 | Attribute_Universal_Literal_String
10207 | Attribute_Unrestricted_Access
10209 | Attribute_Valid_Scalars
10211 | Attribute_Wchar_T_Size
10212 | Attribute_Wide_Value
10213 | Attribute_Wide_Wide_Value
10214 | Attribute_Word_Size
10217 raise Program_Error
;
10220 -- At the end of the case, one more check. If we did a static evaluation
10221 -- so that the result is now a literal, then set Is_Static_Expression
10222 -- in the constant only if the prefix type is a static subtype. For
10223 -- non-static subtypes, the folding is still OK, but not static.
10225 -- An exception is the GNAT attribute Constrained_Array which is
10226 -- defined to be a static attribute in all cases.
10228 if Nkind_In
(N
, N_Integer_Literal
,
10230 N_Character_Literal
,
10232 or else (Is_Entity_Name
(N
)
10233 and then Ekind
(Entity
(N
)) = E_Enumeration_Literal
)
10235 Set_Is_Static_Expression
(N
, Static
);
10237 -- If this is still an attribute reference, then it has not been folded
10238 -- and that means that its expressions are in a non-static context.
10240 elsif Nkind
(N
) = N_Attribute_Reference
then
10243 -- Note: the else case not covered here are odd cases where the
10244 -- processing has transformed the attribute into something other
10245 -- than a constant. Nothing more to do in such cases.
10250 end Eval_Attribute
;
10252 ------------------------------
10253 -- Is_Anonymous_Tagged_Base --
10254 ------------------------------
10256 function Is_Anonymous_Tagged_Base
10258 Typ
: Entity_Id
) return Boolean
10262 Anon
= Current_Scope
10263 and then Is_Itype
(Anon
)
10264 and then Associated_Node_For_Itype
(Anon
) = Parent
(Typ
);
10265 end Is_Anonymous_Tagged_Base
;
10267 --------------------------------
10268 -- Name_Implies_Lvalue_Prefix --
10269 --------------------------------
10271 function Name_Implies_Lvalue_Prefix
(Nam
: Name_Id
) return Boolean is
10272 pragma Assert
(Is_Attribute_Name
(Nam
));
10274 return Attribute_Name_Implies_Lvalue_Prefix
(Get_Attribute_Id
(Nam
));
10275 end Name_Implies_Lvalue_Prefix
;
10277 -----------------------
10278 -- Resolve_Attribute --
10279 -----------------------
10281 procedure Resolve_Attribute
(N
: Node_Id
; Typ
: Entity_Id
) is
10282 Loc
: constant Source_Ptr
:= Sloc
(N
);
10283 P
: constant Node_Id
:= Prefix
(N
);
10284 Aname
: constant Name_Id
:= Attribute_Name
(N
);
10285 Attr_Id
: constant Attribute_Id
:= Get_Attribute_Id
(Aname
);
10286 Btyp
: constant Entity_Id
:= Base_Type
(Typ
);
10287 Des_Btyp
: Entity_Id
;
10288 Index
: Interp_Index
;
10290 Nom_Subt
: Entity_Id
;
10292 procedure Accessibility_Message
;
10293 -- Error, or warning within an instance, if the static accessibility
10294 -- rules of 3.10.2 are violated.
10296 function Declared_Within_Generic_Unit
10297 (Entity
: Entity_Id
;
10298 Generic_Unit
: Node_Id
) return Boolean;
10299 -- Returns True if Declared_Entity is declared within the declarative
10300 -- region of Generic_Unit; otherwise returns False.
10302 ---------------------------
10303 -- Accessibility_Message --
10304 ---------------------------
10306 procedure Accessibility_Message
is
10307 Indic
: Node_Id
:= Parent
(Parent
(N
));
10310 -- In an instance, this is a runtime check, but one we
10311 -- know will fail, so generate an appropriate warning.
10313 if In_Instance_Body
then
10314 Error_Msg_Warn
:= SPARK_Mode
/= On
;
10316 ("non-local pointer cannot point to local object<<", P
);
10317 Error_Msg_F
("\Program_Error [<<", P
);
10319 Make_Raise_Program_Error
(Loc
,
10320 Reason
=> PE_Accessibility_Check_Failed
));
10321 Set_Etype
(N
, Typ
);
10325 Error_Msg_F
("non-local pointer cannot point to local object", P
);
10327 -- Check for case where we have a missing access definition
10329 if Is_Record_Type
(Current_Scope
)
10331 Nkind_In
(Parent
(N
), N_Discriminant_Association
,
10332 N_Index_Or_Discriminant_Constraint
)
10334 Indic
:= Parent
(Parent
(N
));
10335 while Present
(Indic
)
10336 and then Nkind
(Indic
) /= N_Subtype_Indication
10338 Indic
:= Parent
(Indic
);
10341 if Present
(Indic
) then
10343 ("\use an access definition for" &
10344 " the access discriminant of&",
10345 N
, Entity
(Subtype_Mark
(Indic
)));
10349 end Accessibility_Message
;
10351 ----------------------------------
10352 -- Declared_Within_Generic_Unit --
10353 ----------------------------------
10355 function Declared_Within_Generic_Unit
10356 (Entity
: Entity_Id
;
10357 Generic_Unit
: Node_Id
) return Boolean
10359 Generic_Encloser
: Node_Id
:= Enclosing_Generic_Unit
(Entity
);
10362 while Present
(Generic_Encloser
) loop
10363 if Generic_Encloser
= Generic_Unit
then
10367 -- We have to step to the scope of the generic's entity, because
10368 -- otherwise we'll just get back the same generic.
10370 Generic_Encloser
:=
10371 Enclosing_Generic_Unit
10372 (Scope
(Defining_Entity
(Generic_Encloser
)));
10376 end Declared_Within_Generic_Unit
;
10378 -- Start of processing for Resolve_Attribute
10381 -- If error during analysis, no point in continuing, except for array
10382 -- types, where we get better recovery by using unconstrained indexes
10383 -- than nothing at all (see Check_Array_Type).
10385 if Error_Posted
(N
)
10386 and then Attr_Id
/= Attribute_First
10387 and then Attr_Id
/= Attribute_Last
10388 and then Attr_Id
/= Attribute_Length
10389 and then Attr_Id
/= Attribute_Range
10394 -- If attribute was universal type, reset to actual type
10396 if Etype
(N
) = Universal_Integer
10397 or else Etype
(N
) = Universal_Real
10399 Set_Etype
(N
, Typ
);
10402 -- Remaining processing depends on attribute
10410 -- For access attributes, if the prefix denotes an entity, it is
10411 -- interpreted as a name, never as a call. It may be overloaded,
10412 -- in which case resolution uses the profile of the context type.
10413 -- Otherwise prefix must be resolved.
10415 when Attribute_Access
10416 | Attribute_Unchecked_Access
10417 | Attribute_Unrestricted_Access
10419 -- Note possible modification if we have a variable
10421 if Is_Variable
(P
) then
10423 PN
: constant Node_Id
:= Parent
(N
);
10426 Note
: Boolean := True;
10427 -- Skip this for the case of Unrestricted_Access occuring in
10428 -- the context of a Valid check, since this otherwise leads
10429 -- to a missed warning (the Valid check does not really
10430 -- modify!) If this case, Note will be reset to False.
10432 -- Skip it as well if the type is an Acccess_To_Constant,
10433 -- given that no use of the value can modify the prefix.
10436 if Attr_Id
= Attribute_Unrestricted_Access
10437 and then Nkind
(PN
) = N_Function_Call
10441 if Nkind
(Nm
) = N_Expanded_Name
10442 and then Chars
(Nm
) = Name_Valid
10443 and then Nkind
(Prefix
(Nm
)) = N_Identifier
10444 and then Chars
(Prefix
(Nm
)) = Name_Attr_Long_Float
10449 elsif Is_Access_Constant
(Typ
) then
10454 Note_Possible_Modification
(P
, Sure
=> False);
10459 -- The following comes from a query concerning improper use of
10460 -- universal_access in equality tests involving anonymous access
10461 -- types. Another good reason for 'Ref, but for now disable the
10462 -- test, which breaks several filed tests???
10464 if Ekind
(Typ
) = E_Anonymous_Access_Type
10465 and then Nkind_In
(Parent
(N
), N_Op_Eq
, N_Op_Ne
)
10468 Error_Msg_N
("need unique type to resolve 'Access", N
);
10469 Error_Msg_N
("\qualify attribute with some access type", N
);
10472 -- Case where prefix is an entity name
10474 if Is_Entity_Name
(P
) then
10476 -- Deal with case where prefix itself is overloaded
10478 if Is_Overloaded
(P
) then
10479 Get_First_Interp
(P
, Index
, It
);
10480 while Present
(It
.Nam
) loop
10481 if Type_Conformant
(Designated_Type
(Typ
), It
.Nam
) then
10482 Set_Entity
(P
, It
.Nam
);
10484 -- The prefix is definitely NOT overloaded anymore at
10485 -- this point, so we reset the Is_Overloaded flag to
10486 -- avoid any confusion when reanalyzing the node.
10488 Set_Is_Overloaded
(P
, False);
10489 Set_Is_Overloaded
(N
, False);
10490 Generate_Reference
(Entity
(P
), P
);
10494 Get_Next_Interp
(Index
, It
);
10497 -- If Prefix is a subprogram name, this reference freezes,
10498 -- but not if within spec expression mode. The profile of
10499 -- the subprogram is not frozen at this point.
10501 if not In_Spec_Expression
then
10502 Freeze_Before
(N
, Entity
(P
), Do_Freeze_Profile
=> False);
10505 -- If it is a type, there is nothing to resolve.
10506 -- If it is a subprogram, do not freeze its profile.
10507 -- If it is an object, complete its resolution.
10509 elsif Is_Overloadable
(Entity
(P
)) then
10510 if not In_Spec_Expression
then
10511 Freeze_Before
(N
, Entity
(P
), Do_Freeze_Profile
=> False);
10514 -- Nothing to do if prefix is a type name
10516 elsif Is_Type
(Entity
(P
)) then
10519 -- Otherwise non-overloaded other case, resolve the prefix
10525 -- Some further error checks
10527 Error_Msg_Name_1
:= Aname
;
10529 if not Is_Entity_Name
(P
) then
10532 elsif Is_Overloadable
(Entity
(P
))
10533 and then Is_Abstract_Subprogram
(Entity
(P
))
10535 Error_Msg_F
("prefix of % attribute cannot be abstract", P
);
10536 Set_Etype
(N
, Any_Type
);
10538 elsif Ekind
(Entity
(P
)) = E_Enumeration_Literal
then
10540 ("prefix of % attribute cannot be enumeration literal", P
);
10541 Set_Etype
(N
, Any_Type
);
10543 -- An attempt to take 'Access of a function that renames an
10544 -- enumeration literal. Issue a specialized error message.
10546 elsif Ekind
(Entity
(P
)) = E_Function
10547 and then Present
(Alias
(Entity
(P
)))
10548 and then Ekind
(Alias
(Entity
(P
))) = E_Enumeration_Literal
10551 ("prefix of % attribute cannot be function renaming "
10552 & "an enumeration literal", P
);
10553 Set_Etype
(N
, Any_Type
);
10555 elsif Convention
(Entity
(P
)) = Convention_Intrinsic
then
10556 Error_Msg_F
("prefix of % attribute cannot be intrinsic", P
);
10557 Set_Etype
(N
, Any_Type
);
10560 -- Assignments, return statements, components of aggregates,
10561 -- generic instantiations will require convention checks if
10562 -- the type is an access to subprogram. Given that there will
10563 -- also be accessibility checks on those, this is where the
10564 -- checks can eventually be centralized ???
10566 if Ekind_In
(Btyp
, E_Access_Protected_Subprogram_Type
,
10567 E_Access_Subprogram_Type
,
10568 E_Anonymous_Access_Protected_Subprogram_Type
,
10569 E_Anonymous_Access_Subprogram_Type
)
10571 -- Deal with convention mismatch
10573 if Convention
(Designated_Type
(Btyp
)) /=
10574 Convention
(Entity
(P
))
10576 -- The rule in 6.3.1 (8) deserves a special error
10579 if Convention
(Btyp
) = Convention_Intrinsic
10580 and then Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
10581 and then Is_Entity_Name
(Name
(Parent
(N
)))
10582 and then Inside_A_Generic
10585 Subp
: constant Entity_Id
:=
10586 Entity
(Name
(Parent
(N
)));
10588 if Convention
(Subp
) = Convention_Intrinsic
then
10590 ("?subprogram and its formal access "
10591 & "parameters have convention Intrinsic",
10594 ("actual cannot be access attribute", N
);
10600 ("subprogram & has wrong convention", P
, Entity
(P
));
10601 Error_Msg_Sloc
:= Sloc
(Btyp
);
10602 Error_Msg_FE
("\does not match & declared#", P
, Btyp
);
10605 if not Is_Itype
(Btyp
)
10606 and then not Has_Convention_Pragma
(Btyp
)
10609 ("\probable missing pragma Convention for &",
10614 Check_Subtype_Conformant
10615 (New_Id
=> Entity
(P
),
10616 Old_Id
=> Designated_Type
(Btyp
),
10620 if Attr_Id
= Attribute_Unchecked_Access
then
10621 Error_Msg_Name_1
:= Aname
;
10623 ("attribute% cannot be applied to a subprogram", P
);
10625 elsif Aname
= Name_Unrestricted_Access
then
10626 null; -- Nothing to check
10628 -- Check the static accessibility rule of 3.10.2(32).
10629 -- This rule also applies within the private part of an
10630 -- instantiation. This rule does not apply to anonymous
10631 -- access-to-subprogram types in access parameters.
10633 elsif Attr_Id
= Attribute_Access
10634 and then not In_Instance_Body
10636 (Ekind
(Btyp
) = E_Access_Subprogram_Type
10637 or else Is_Local_Anonymous_Access
(Btyp
))
10638 and then Subprogram_Access_Level
(Entity
(P
)) >
10639 Type_Access_Level
(Btyp
)
10642 ("subprogram must not be deeper than access type", P
);
10644 -- Check the restriction of 3.10.2(32) that disallows the
10645 -- access attribute within a generic body when the ultimate
10646 -- ancestor of the type of the attribute is declared outside
10647 -- of the generic unit and the subprogram is declared within
10648 -- that generic unit. This includes any such attribute that
10649 -- occurs within the body of a generic unit that is a child
10650 -- of the generic unit where the subprogram is declared.
10652 -- The rule also prohibits applying the attribute when the
10653 -- access type is a generic formal access type (since the
10654 -- level of the actual type is not known). This restriction
10655 -- does not apply when the attribute type is an anonymous
10656 -- access-to-subprogram type. Note that this check was
10657 -- revised by AI-229, because the original Ada 95 rule
10658 -- was too lax. The original rule only applied when the
10659 -- subprogram was declared within the body of the generic,
10660 -- which allowed the possibility of dangling references).
10661 -- The rule was also too strict in some cases, in that it
10662 -- didn't permit the access to be declared in the generic
10663 -- spec, whereas the revised rule does (as long as it's not
10666 -- There are a couple of subtleties of the test for applying
10667 -- the check that are worth noting. First, we only apply it
10668 -- when the levels of the subprogram and access type are the
10669 -- same (the case where the subprogram is statically deeper
10670 -- was applied above, and the case where the type is deeper
10671 -- is always safe). Second, we want the check to apply
10672 -- within nested generic bodies and generic child unit
10673 -- bodies, but not to apply to an attribute that appears in
10674 -- the generic unit's specification. This is done by testing
10675 -- that the attribute's innermost enclosing generic body is
10676 -- not the same as the innermost generic body enclosing the
10677 -- generic unit where the subprogram is declared (we don't
10678 -- want the check to apply when the access attribute is in
10679 -- the spec and there's some other generic body enclosing
10680 -- generic). Finally, there's no point applying the check
10681 -- when within an instance, because any violations will have
10682 -- been caught by the compilation of the generic unit.
10684 -- We relax this check in Relaxed_RM_Semantics mode for
10685 -- compatibility with legacy code for use by Ada source
10686 -- code analyzers (e.g. CodePeer).
10688 elsif Attr_Id
= Attribute_Access
10689 and then not Relaxed_RM_Semantics
10690 and then not In_Instance
10691 and then Present
(Enclosing_Generic_Unit
(Entity
(P
)))
10692 and then Present
(Enclosing_Generic_Body
(N
))
10693 and then Enclosing_Generic_Body
(N
) /=
10694 Enclosing_Generic_Body
10695 (Enclosing_Generic_Unit
(Entity
(P
)))
10696 and then Subprogram_Access_Level
(Entity
(P
)) =
10697 Type_Access_Level
(Btyp
)
10698 and then Ekind
(Btyp
) /=
10699 E_Anonymous_Access_Subprogram_Type
10700 and then Ekind
(Btyp
) /=
10701 E_Anonymous_Access_Protected_Subprogram_Type
10703 -- The attribute type's ultimate ancestor must be
10704 -- declared within the same generic unit as the
10705 -- subprogram is declared (including within another
10706 -- nested generic unit). The error message is
10707 -- specialized to say "ancestor" for the case where the
10708 -- access type is not its own ancestor, since saying
10709 -- simply "access type" would be very confusing.
10711 if not Declared_Within_Generic_Unit
10713 Enclosing_Generic_Unit
(Entity
(P
)))
10716 ("''Access attribute not allowed in generic body",
10719 if Root_Type
(Btyp
) = Btyp
then
10722 "access type & is declared outside " &
10723 "generic unit (RM 3.10.2(32))", N
, Btyp
);
10726 ("\because ancestor of " &
10727 "access type & is declared outside " &
10728 "generic unit (RM 3.10.2(32))", N
, Btyp
);
10732 ("\move ''Access to private part, or " &
10733 "(Ada 2005) use anonymous access type instead of &",
10736 -- If the ultimate ancestor of the attribute's type is
10737 -- a formal type, then the attribute is illegal because
10738 -- the actual type might be declared at a higher level.
10739 -- The error message is specialized to say "ancestor"
10740 -- for the case where the access type is not its own
10741 -- ancestor, since saying simply "access type" would be
10744 elsif Is_Generic_Type
(Root_Type
(Btyp
)) then
10745 if Root_Type
(Btyp
) = Btyp
then
10747 ("access type must not be a generic formal type",
10751 ("ancestor access type must not be a generic " &
10758 -- If this is a renaming, an inherited operation, or a
10759 -- subprogram instance, use the original entity. This may make
10760 -- the node type-inconsistent, so this transformation can only
10761 -- be done if the node will not be reanalyzed. In particular,
10762 -- if it is within a default expression, the transformation
10763 -- must be delayed until the default subprogram is created for
10764 -- it, when the enclosing subprogram is frozen.
10766 if Is_Entity_Name
(P
)
10767 and then Is_Overloadable
(Entity
(P
))
10768 and then Present
(Alias
(Entity
(P
)))
10769 and then Expander_Active
10772 New_Occurrence_Of
(Alias
(Entity
(P
)), Sloc
(P
)));
10775 elsif Nkind
(P
) = N_Selected_Component
10776 and then Is_Overloadable
(Entity
(Selector_Name
(P
)))
10778 -- Protected operation. If operation is overloaded, must
10779 -- disambiguate. Prefix that denotes protected object itself
10780 -- is resolved with its own type.
10782 if Attr_Id
= Attribute_Unchecked_Access
then
10783 Error_Msg_Name_1
:= Aname
;
10785 ("attribute% cannot be applied to protected operation", P
);
10788 Resolve
(Prefix
(P
));
10789 Generate_Reference
(Entity
(Selector_Name
(P
)), P
);
10791 -- Implement check implied by 3.10.2 (18.1/2) : F.all'access is
10792 -- statically illegal if F is an anonymous access to subprogram.
10794 elsif Nkind
(P
) = N_Explicit_Dereference
10795 and then Is_Entity_Name
(Prefix
(P
))
10796 and then Ekind
(Etype
(Entity
(Prefix
(P
)))) =
10797 E_Anonymous_Access_Subprogram_Type
10799 Error_Msg_N
("anonymous access to subprogram "
10800 & "has deeper accessibility than any master", P
);
10802 elsif Is_Overloaded
(P
) then
10804 -- Use the designated type of the context to disambiguate
10805 -- Note that this was not strictly conformant to Ada 95,
10806 -- but was the implementation adopted by most Ada 95 compilers.
10807 -- The use of the context type to resolve an Access attribute
10808 -- reference is now mandated in AI-235 for Ada 2005.
10811 Index
: Interp_Index
;
10815 Get_First_Interp
(P
, Index
, It
);
10816 while Present
(It
.Typ
) loop
10817 if Covers
(Designated_Type
(Typ
), It
.Typ
) then
10818 Resolve
(P
, It
.Typ
);
10822 Get_Next_Interp
(Index
, It
);
10829 -- X'Access is illegal if X denotes a constant and the access type
10830 -- is access-to-variable. Same for 'Unchecked_Access. The rule
10831 -- does not apply to 'Unrestricted_Access. If the reference is a
10832 -- default-initialized aggregate component for a self-referential
10833 -- type the reference is legal.
10835 if not (Ekind
(Btyp
) = E_Access_Subprogram_Type
10836 or else Ekind
(Btyp
) = E_Anonymous_Access_Subprogram_Type
10837 or else (Is_Record_Type
(Btyp
)
10839 Present
(Corresponding_Remote_Type
(Btyp
)))
10840 or else Ekind
(Btyp
) = E_Access_Protected_Subprogram_Type
10841 or else Ekind
(Btyp
)
10842 = E_Anonymous_Access_Protected_Subprogram_Type
10843 or else Is_Access_Constant
(Btyp
)
10844 or else Is_Variable
(P
)
10845 or else Attr_Id
= Attribute_Unrestricted_Access
)
10847 if Is_Entity_Name
(P
)
10848 and then Is_Type
(Entity
(P
))
10850 -- Legality of a self-reference through an access
10851 -- attribute has been verified in Analyze_Access_Attribute.
10855 elsif Comes_From_Source
(N
) then
10856 Error_Msg_F
("access-to-variable designates constant", P
);
10860 Des_Btyp
:= Designated_Type
(Btyp
);
10862 if Ada_Version
>= Ada_2005
10863 and then Is_Incomplete_Type
(Des_Btyp
)
10865 -- Ada 2005 (AI-412): If the (sub)type is a limited view of an
10866 -- imported entity, and the non-limited view is visible, make
10867 -- use of it. If it is an incomplete subtype, use the base type
10870 if From_Limited_With
(Des_Btyp
)
10871 and then Present
(Non_Limited_View
(Des_Btyp
))
10873 Des_Btyp
:= Non_Limited_View
(Des_Btyp
);
10875 elsif Ekind
(Des_Btyp
) = E_Incomplete_Subtype
then
10876 Des_Btyp
:= Etype
(Des_Btyp
);
10880 if (Attr_Id
= Attribute_Access
10882 Attr_Id
= Attribute_Unchecked_Access
)
10883 and then (Ekind
(Btyp
) = E_General_Access_Type
10884 or else Ekind
(Btyp
) = E_Anonymous_Access_Type
)
10886 -- Ada 2005 (AI-230): Check the accessibility of anonymous
10887 -- access types for stand-alone objects, record and array
10888 -- components, and return objects. For a component definition
10889 -- the level is the same of the enclosing composite type.
10891 if Ada_Version
>= Ada_2005
10892 and then (Is_Local_Anonymous_Access
(Btyp
)
10894 -- Handle cases where Btyp is the anonymous access
10895 -- type of an Ada 2012 stand-alone object.
10897 or else Nkind
(Associated_Node_For_Itype
(Btyp
)) =
10898 N_Object_Declaration
)
10900 Object_Access_Level
(P
) > Deepest_Type_Access_Level
(Btyp
)
10901 and then Attr_Id
= Attribute_Access
10903 -- In an instance, this is a runtime check, but one we know
10904 -- will fail, so generate an appropriate warning. As usual,
10905 -- this kind of warning is an error in SPARK mode.
10907 if In_Instance_Body
then
10908 Error_Msg_Warn
:= SPARK_Mode
/= On
;
10910 ("non-local pointer cannot point to local object<<", P
);
10911 Error_Msg_F
("\Program_Error [<<", P
);
10914 Make_Raise_Program_Error
(Loc
,
10915 Reason
=> PE_Accessibility_Check_Failed
));
10916 Set_Etype
(N
, Typ
);
10920 ("non-local pointer cannot point to local object", P
);
10924 if Is_Dependent_Component_Of_Mutable_Object
(P
) then
10926 ("illegal attribute for discriminant-dependent component",
10930 -- Check static matching rule of 3.10.2(27). Nominal subtype
10931 -- of the prefix must statically match the designated type.
10933 Nom_Subt
:= Etype
(P
);
10935 if Is_Constr_Subt_For_U_Nominal
(Nom_Subt
) then
10936 Nom_Subt
:= Base_Type
(Nom_Subt
);
10939 if Is_Tagged_Type
(Designated_Type
(Typ
)) then
10941 -- If the attribute is in the context of an access
10942 -- parameter, then the prefix is allowed to be of
10943 -- the class-wide type (by AI-127).
10945 if Ekind
(Typ
) = E_Anonymous_Access_Type
then
10946 if not Covers
(Designated_Type
(Typ
), Nom_Subt
)
10947 and then not Covers
(Nom_Subt
, Designated_Type
(Typ
))
10953 Desig
:= Designated_Type
(Typ
);
10955 if Is_Class_Wide_Type
(Desig
) then
10956 Desig
:= Etype
(Desig
);
10959 if Is_Anonymous_Tagged_Base
(Nom_Subt
, Desig
) then
10964 ("type of prefix: & not compatible",
10967 ("\with &, the expected designated type",
10968 P
, Designated_Type
(Typ
));
10973 elsif not Covers
(Designated_Type
(Typ
), Nom_Subt
)
10975 (not Is_Class_Wide_Type
(Designated_Type
(Typ
))
10976 and then Is_Class_Wide_Type
(Nom_Subt
))
10979 ("type of prefix: & is not covered", P
, Nom_Subt
);
10981 ("\by &, the expected designated type" &
10982 " (RM 3.10.2 (27))", P
, Designated_Type
(Typ
));
10985 if Is_Class_Wide_Type
(Designated_Type
(Typ
))
10986 and then Has_Discriminants
(Etype
(Designated_Type
(Typ
)))
10987 and then Is_Constrained
(Etype
(Designated_Type
(Typ
)))
10988 and then Designated_Type
(Typ
) /= Nom_Subt
10990 Apply_Discriminant_Check
10991 (N
, Etype
(Designated_Type
(Typ
)));
10994 -- Ada 2005 (AI-363): Require static matching when designated
10995 -- type has discriminants and a constrained partial view, since
10996 -- in general objects of such types are mutable, so we can't
10997 -- allow the access value to designate a constrained object
10998 -- (because access values must be assumed to designate mutable
10999 -- objects when designated type does not impose a constraint).
11001 elsif Subtypes_Statically_Match
(Des_Btyp
, Nom_Subt
) then
11004 elsif Has_Discriminants
(Designated_Type
(Typ
))
11005 and then not Is_Constrained
(Des_Btyp
)
11007 (Ada_Version
< Ada_2005
11009 not Object_Type_Has_Constrained_Partial_View
11010 (Typ
=> Designated_Type
(Base_Type
(Typ
)),
11011 Scop
=> Current_Scope
))
11017 ("object subtype must statically match "
11018 & "designated subtype", P
);
11020 if Is_Entity_Name
(P
)
11021 and then Is_Array_Type
(Designated_Type
(Typ
))
11024 D
: constant Node_Id
:= Declaration_Node
(Entity
(P
));
11027 ("aliased object has explicit bounds??", D
);
11029 ("\declare without bounds (and with explicit "
11030 & "initialization)??", D
);
11032 ("\for use with unconstrained access??", D
);
11037 -- Check the static accessibility rule of 3.10.2(28). Note that
11038 -- this check is not performed for the case of an anonymous
11039 -- access type, since the access attribute is always legal
11040 -- in such a context.
11042 if Attr_Id
/= Attribute_Unchecked_Access
11043 and then Ekind
(Btyp
) = E_General_Access_Type
11045 Object_Access_Level
(P
) > Deepest_Type_Access_Level
(Btyp
)
11047 Accessibility_Message
;
11052 if Ekind_In
(Btyp
, E_Access_Protected_Subprogram_Type
,
11053 E_Anonymous_Access_Protected_Subprogram_Type
)
11055 if Is_Entity_Name
(P
)
11056 and then not Is_Protected_Type
(Scope
(Entity
(P
)))
11058 Error_Msg_F
("context requires a protected subprogram", P
);
11060 -- Check accessibility of protected object against that of the
11061 -- access type, but only on user code, because the expander
11062 -- creates access references for handlers. If the context is an
11063 -- anonymous_access_to_protected, there are no accessibility
11064 -- checks either. Omit check entirely for Unrestricted_Access.
11066 elsif Object_Access_Level
(P
) > Deepest_Type_Access_Level
(Btyp
)
11067 and then Comes_From_Source
(N
)
11068 and then Ekind
(Btyp
) = E_Access_Protected_Subprogram_Type
11069 and then Attr_Id
/= Attribute_Unrestricted_Access
11071 Accessibility_Message
;
11074 -- AI05-0225: If the context is not an access to protected
11075 -- function, the prefix must be a variable, given that it may
11076 -- be used subsequently in a protected call.
11078 elsif Nkind
(P
) = N_Selected_Component
11079 and then not Is_Variable
(Prefix
(P
))
11080 and then Ekind
(Entity
(Selector_Name
(P
))) /= E_Function
11083 ("target object of access to protected procedure "
11084 & "must be variable", N
);
11086 elsif Is_Entity_Name
(P
) then
11087 Check_Internal_Protected_Use
(N
, Entity
(P
));
11090 elsif Ekind_In
(Btyp
, E_Access_Subprogram_Type
,
11091 E_Anonymous_Access_Subprogram_Type
)
11092 and then Ekind
(Etype
(N
)) = E_Access_Protected_Subprogram_Type
11094 Error_Msg_F
("context requires a non-protected subprogram", P
);
11097 -- The context cannot be a pool-specific type, but this is a
11098 -- legality rule, not a resolution rule, so it must be checked
11099 -- separately, after possibly disambiguation (see AI-245).
11101 if Ekind
(Btyp
) = E_Access_Type
11102 and then Attr_Id
/= Attribute_Unrestricted_Access
11104 Wrong_Type
(N
, Typ
);
11107 -- The context may be a constrained access type (however ill-
11108 -- advised such subtypes might be) so in order to generate a
11109 -- constraint check we need to set the type of the attribute
11110 -- reference to the base type of the context.
11112 Set_Etype
(N
, Btyp
);
11114 -- Check for incorrect atomic/volatile reference (RM C.6(12))
11116 if Attr_Id
/= Attribute_Unrestricted_Access
then
11117 if Is_Atomic_Object
(P
)
11118 and then not Is_Atomic
(Designated_Type
(Typ
))
11121 ("access to atomic object cannot yield access-to-" &
11122 "non-atomic type", P
);
11124 elsif Is_Volatile_Object
(P
)
11125 and then not Is_Volatile
(Designated_Type
(Typ
))
11128 ("access to volatile object cannot yield access-to-" &
11129 "non-volatile type", P
);
11133 -- Check for aliased view. We allow a nonaliased prefix when in
11134 -- an instance because the prefix may have been a tagged formal
11135 -- object, which is defined to be aliased even when the actual
11136 -- might not be (other instance cases will have been caught in
11137 -- the generic). Similarly, within an inlined body we know that
11138 -- the attribute is legal in the original subprogram, therefore
11139 -- legal in the expansion.
11141 if not (Is_Entity_Name
(P
)
11142 and then Is_Overloadable
(Entity
(P
)))
11143 and then not (Nkind
(P
) = N_Selected_Component
11145 Is_Overloadable
(Entity
(Selector_Name
(P
))))
11146 and then not Is_Aliased_View
(Original_Node
(P
))
11147 and then not In_Instance
11148 and then not In_Inlined_Body
11149 and then Comes_From_Source
(N
)
11151 -- Here we have a non-aliased view. This is illegal unless we
11152 -- have the case of Unrestricted_Access, where for now we allow
11153 -- this (we will reject later if expected type is access to an
11154 -- unconstrained array with a thin pointer).
11156 -- No need for an error message on a generated access reference
11157 -- for the controlling argument in a dispatching call: error
11158 -- will be reported when resolving the call.
11160 if Attr_Id
/= Attribute_Unrestricted_Access
then
11161 Error_Msg_N
("prefix of % attribute must be aliased", P
);
11163 -- Check for unrestricted access where expected type is a thin
11164 -- pointer to an unconstrained array.
11166 elsif Has_Size_Clause
(Typ
)
11167 and then RM_Size
(Typ
) = System_Address_Size
11170 DT
: constant Entity_Id
:= Designated_Type
(Typ
);
11172 if Is_Array_Type
(DT
)
11173 and then not Is_Constrained
(DT
)
11176 ("illegal use of Unrestricted_Access attribute", P
);
11178 ("\attempt to generate thin pointer to unaliased "
11185 -- Mark that address of entity is taken in case of
11186 -- 'Unrestricted_Access or in case of a subprogram.
11188 if Is_Entity_Name
(P
)
11189 and then (Attr_Id
= Attribute_Unrestricted_Access
11190 or else Is_Subprogram
(Entity
(P
)))
11192 Set_Address_Taken
(Entity
(P
));
11195 -- Deal with possible elaboration check
11197 if Is_Entity_Name
(P
) and then Is_Subprogram
(Entity
(P
)) then
11199 Subp_Id
: constant Entity_Id
:= Entity
(P
);
11200 Scop
: constant Entity_Id
:= Scope
(Subp_Id
);
11201 Subp_Decl
: constant Node_Id
:=
11202 Unit_Declaration_Node
(Subp_Id
);
11203 Flag_Id
: Entity_Id
;
11204 Subp_Body
: Node_Id
;
11206 -- If the access has been taken and the body of the subprogram
11207 -- has not been see yet, indirect calls must be protected with
11208 -- elaboration checks. We have the proper elaboration machinery
11209 -- for subprograms declared in packages, but within a block or
11210 -- a subprogram the body will appear in the same declarative
11211 -- part, and we must insert a check in the eventual body itself
11212 -- using the elaboration flag that we generate now. The check
11213 -- is then inserted when the body is expanded. This processing
11214 -- is not needed for a stand alone expression function because
11215 -- the internally generated spec and body are always inserted
11216 -- as a pair in the same declarative list.
11220 and then Comes_From_Source
(Subp_Id
)
11221 and then Comes_From_Source
(N
)
11222 and then In_Open_Scopes
(Scop
)
11223 and then Ekind_In
(Scop
, E_Block
, E_Procedure
, E_Function
)
11224 and then not Has_Completion
(Subp_Id
)
11225 and then No
(Elaboration_Entity
(Subp_Id
))
11226 and then Nkind
(Subp_Decl
) = N_Subprogram_Declaration
11227 and then Nkind
(Original_Node
(Subp_Decl
)) /=
11228 N_Expression_Function
11230 -- Create elaboration variable for it
11232 Flag_Id
:= Make_Temporary
(Loc
, 'E');
11233 Set_Elaboration_Entity
(Subp_Id
, Flag_Id
);
11234 Set_Is_Frozen
(Flag_Id
);
11236 -- Insert declaration for flag after subprogram
11237 -- declaration. Note that attribute reference may
11238 -- appear within a nested scope.
11240 Insert_After_And_Analyze
(Subp_Decl
,
11241 Make_Object_Declaration
(Loc
,
11242 Defining_Identifier
=> Flag_Id
,
11243 Object_Definition
=>
11244 New_Occurrence_Of
(Standard_Short_Integer
, Loc
),
11246 Make_Integer_Literal
(Loc
, Uint_0
)));
11248 -- The above sets the Scope of the flag entity to the
11249 -- current scope, in which the attribute appears, but
11250 -- the flag declaration has been inserted after that
11251 -- of Subp_Id, so the scope of the flag is the same as
11252 -- that of Subp_Id. This is relevant when unnesting,
11253 -- where processing depends on correct scope setting.
11255 Set_Scope
(Flag_Id
, Scop
);
11258 -- Taking the 'Access of an expression function freezes its
11259 -- expression (RM 13.14 10.3/3). This does not apply to an
11260 -- expression function that acts as a completion because the
11261 -- generated body is immediately analyzed and the expression
11262 -- is automatically frozen.
11264 if Is_Expression_Function
(Subp_Id
)
11265 and then Present
(Corresponding_Body
(Subp_Decl
))
11268 Unit_Declaration_Node
(Corresponding_Body
(Subp_Decl
));
11270 -- The body has already been analyzed when the expression
11271 -- function acts as a completion.
11273 if Analyzed
(Subp_Body
) then
11276 -- Attribute 'Access may appear within the generated body
11277 -- of the expression function subject to the attribute:
11279 -- function F is (... F'Access ...);
11281 -- If the expression function is on the scope stack, then
11282 -- the body is currently being analyzed. Do not reanalyze
11283 -- it because this will lead to infinite recursion.
11285 elsif In_Open_Scopes
(Subp_Id
) then
11288 -- If reference to the expression function appears in an
11289 -- inner scope, for example as an actual in an instance,
11290 -- this is not a freeze point either.
11292 elsif Scope
(Subp_Id
) /= Current_Scope
then
11295 -- Analyze the body of the expression function to freeze
11296 -- the expression. This takes care of the case where the
11297 -- 'Access is part of dispatch table initialization and
11298 -- the generated body of the expression function has not
11299 -- been analyzed yet.
11302 Analyze
(Subp_Body
);
11312 -- Deal with resolving the type for Address attribute, overloading
11313 -- is not permitted here, since there is no context to resolve it.
11315 when Attribute_Address
11316 | Attribute_Code_Address
11318 -- To be safe, assume that if the address of a variable is taken,
11319 -- it may be modified via this address, so note modification.
11321 if Is_Variable
(P
) then
11322 Note_Possible_Modification
(P
, Sure
=> False);
11325 if Nkind
(P
) in N_Subexpr
11326 and then Is_Overloaded
(P
)
11328 Get_First_Interp
(P
, Index
, It
);
11329 Get_Next_Interp
(Index
, It
);
11331 if Present
(It
.Nam
) then
11332 Error_Msg_Name_1
:= Aname
;
11334 ("prefix of % attribute cannot be overloaded", P
);
11338 if not Is_Entity_Name
(P
)
11339 or else not Is_Overloadable
(Entity
(P
))
11341 if not Is_Task_Type
(Etype
(P
))
11342 or else Nkind
(P
) = N_Explicit_Dereference
11348 -- If this is the name of a derived subprogram, or that of a
11349 -- generic actual, the address is that of the original entity.
11351 if Is_Entity_Name
(P
)
11352 and then Is_Overloadable
(Entity
(P
))
11353 and then Present
(Alias
(Entity
(P
)))
11356 New_Occurrence_Of
(Alias
(Entity
(P
)), Sloc
(P
)));
11359 if Is_Entity_Name
(P
) then
11360 Set_Address_Taken
(Entity
(P
));
11363 if Nkind
(P
) = N_Slice
then
11365 -- Arr (X .. Y)'address is identical to Arr (X)'address,
11366 -- even if the array is packed and the slice itself is not
11367 -- addressable. Transform the prefix into an indexed component.
11369 -- Note that the transformation is safe only if we know that
11370 -- the slice is non-null. That is because a null slice can have
11371 -- an out of bounds index value.
11373 -- Right now, gigi blows up if given 'Address on a slice as a
11374 -- result of some incorrect freeze nodes generated by the front
11375 -- end, and this covers up that bug in one case, but the bug is
11376 -- likely still there in the cases not handled by this code ???
11378 -- It's not clear what 'Address *should* return for a null
11379 -- slice with out of bounds indexes, this might be worth an ARG
11382 -- One approach would be to do a length check unconditionally,
11383 -- and then do the transformation below unconditionally, but
11384 -- analyze with checks off, avoiding the problem of the out of
11385 -- bounds index. This approach would interpret the address of
11386 -- an out of bounds null slice as being the address where the
11387 -- array element would be if there was one, which is probably
11388 -- as reasonable an interpretation as any ???
11391 Loc
: constant Source_Ptr
:= Sloc
(P
);
11392 D
: constant Node_Id
:= Discrete_Range
(P
);
11396 if Is_Entity_Name
(D
)
11399 (Type_Low_Bound
(Entity
(D
)),
11400 Type_High_Bound
(Entity
(D
)))
11403 Make_Attribute_Reference
(Loc
,
11404 Prefix
=> (New_Occurrence_Of
(Entity
(D
), Loc
)),
11405 Attribute_Name
=> Name_First
);
11407 elsif Nkind
(D
) = N_Range
11408 and then Not_Null_Range
(Low_Bound
(D
), High_Bound
(D
))
11410 Lo
:= Low_Bound
(D
);
11416 if Present
(Lo
) then
11418 Make_Indexed_Component
(Loc
,
11419 Prefix
=> Relocate_Node
(Prefix
(P
)),
11420 Expressions
=> New_List
(Lo
)));
11422 Analyze_And_Resolve
(P
);
11431 -- Prefix of Body_Version attribute can be a subprogram name which
11432 -- must not be resolved, since this is not a call.
11434 when Attribute_Body_Version
=>
11441 -- Prefix of Caller attribute is an entry name which must not
11442 -- be resolved, since this is definitely not an entry call.
11444 when Attribute_Caller
=>
11451 -- Shares processing with Address attribute
11457 -- If the prefix of the Count attribute is an entry name it must not
11458 -- be resolved, since this is definitely not an entry call. However,
11459 -- if it is an element of an entry family, the index itself may
11460 -- have to be resolved because it can be a general expression.
11462 when Attribute_Count
=>
11463 if Nkind
(P
) = N_Indexed_Component
11464 and then Is_Entity_Name
(Prefix
(P
))
11467 Indx
: constant Node_Id
:= First
(Expressions
(P
));
11468 Fam
: constant Entity_Id
:= Entity
(Prefix
(P
));
11470 Resolve
(Indx
, Entry_Index_Type
(Fam
));
11471 Apply_Range_Check
(Indx
, Entry_Index_Type
(Fam
));
11479 -- Prefix of the Elaborated attribute is a subprogram name which
11480 -- must not be resolved, since this is definitely not a call. Note
11481 -- that it is a library unit, so it cannot be overloaded here.
11483 when Attribute_Elaborated
=>
11490 -- Prefix of Enabled attribute is a check name, which must be treated
11491 -- specially and not touched by Resolve.
11493 when Attribute_Enabled
=>
11500 -- Do not resolve the prefix of Loop_Entry, instead wait until the
11501 -- attribute has been expanded (see Expand_Loop_Entry_Attributes).
11502 -- The delay ensures that any generated checks or temporaries are
11503 -- inserted before the relocated prefix.
11505 when Attribute_Loop_Entry
=>
11508 --------------------
11509 -- Mechanism_Code --
11510 --------------------
11512 -- Prefix of the Mechanism_Code attribute is a function name
11513 -- which must not be resolved. Should we check for overloaded ???
11515 when Attribute_Mechanism_Code
=>
11522 -- Most processing is done in sem_dist, after determining the
11523 -- context type. Node is rewritten as a conversion to a runtime call.
11525 when Attribute_Partition_ID
=>
11526 Process_Partition_Id
(N
);
11533 when Attribute_Pool_Address
=>
11540 -- We replace the Range attribute node with a range expression whose
11541 -- bounds are the 'First and 'Last attributes applied to the same
11542 -- prefix. The reason that we do this transformation here instead of
11543 -- in the expander is that it simplifies other parts of the semantic
11544 -- analysis which assume that the Range has been replaced; thus it
11545 -- must be done even when in semantic-only mode (note that the RM
11546 -- specifically mentions this equivalence, we take care that the
11547 -- prefix is only evaluated once).
11549 when Attribute_Range
=> Range_Attribute
: declare
11555 if not Is_Entity_Name
(P
) or else not Is_Type
(Entity
(P
)) then
11559 Dims
:= Expressions
(N
);
11562 Make_Attribute_Reference
(Loc
,
11563 Prefix
=> Duplicate_Subexpr
(P
, Name_Req
=> True),
11564 Attribute_Name
=> Name_Last
,
11565 Expressions
=> Dims
);
11568 Make_Attribute_Reference
(Loc
,
11570 Attribute_Name
=> Name_First
,
11571 Expressions
=> (Dims
));
11573 -- Do not share the dimension indicator, if present. Even though
11574 -- it is a static constant, its source location may be modified
11575 -- when printing expanded code and node sharing will lead to chaos
11578 if Present
(Dims
) then
11579 Set_Expressions
(LB
, New_List
(New_Copy_Tree
(First
(Dims
))));
11582 -- If the original was marked as Must_Not_Freeze (see code in
11583 -- Sem_Ch3.Make_Index), then make sure the rewriting does not
11586 if Must_Not_Freeze
(N
) then
11587 Set_Must_Not_Freeze
(HB
);
11588 Set_Must_Not_Freeze
(LB
);
11589 Set_Must_Not_Freeze
(Prefix
(HB
));
11590 Set_Must_Not_Freeze
(Prefix
(LB
));
11593 if Raises_Constraint_Error
(Prefix
(N
)) then
11595 -- Preserve Sloc of prefix in the new bounds, so that the
11596 -- posted warning can be removed if we are within unreachable
11599 Set_Sloc
(LB
, Sloc
(Prefix
(N
)));
11600 Set_Sloc
(HB
, Sloc
(Prefix
(N
)));
11603 Rewrite
(N
, Make_Range
(Loc
, LB
, HB
));
11604 Analyze_And_Resolve
(N
, Typ
);
11606 -- Ensure that the expanded range does not have side effects
11608 Force_Evaluation
(LB
);
11609 Force_Evaluation
(HB
);
11611 -- Normally after resolving attribute nodes, Eval_Attribute
11612 -- is called to do any possible static evaluation of the node.
11613 -- However, here since the Range attribute has just been
11614 -- transformed into a range expression it is no longer an
11615 -- attribute node and therefore the call needs to be avoided
11616 -- and is accomplished by simply returning from the procedure.
11619 end Range_Attribute
;
11625 -- We will only come here during the prescan of a spec expression
11626 -- containing a Result attribute. In that case the proper Etype has
11627 -- already been set, and nothing more needs to be done here.
11629 when Attribute_Result
=>
11632 ----------------------
11633 -- Unchecked_Access --
11634 ----------------------
11636 -- Processing is shared with Access
11638 -------------------------
11639 -- Unrestricted_Access --
11640 -------------------------
11642 -- Processing is shared with Access
11648 -- Resolve aggregate components in component associations
11650 when Attribute_Update
=> Update
: declare
11651 Aggr
: constant Node_Id
:= First
(Expressions
(N
));
11652 Typ
: constant Entity_Id
:= Etype
(Prefix
(N
));
11658 -- Set the Etype of the aggregate to that of the prefix, even
11659 -- though the aggregate may not be a proper representation of a
11660 -- value of the type (missing or duplicated associations, etc.)
11661 -- Complete resolution of the prefix. Note that in Ada 2012 it
11662 -- can be a qualified expression that is e.g. an aggregate.
11664 Set_Etype
(Aggr
, Typ
);
11665 Resolve
(Prefix
(N
), Typ
);
11667 -- For an array type, resolve expressions with the component type
11668 -- of the array, and apply constraint checks when needed.
11670 if Is_Array_Type
(Typ
) then
11671 Assoc
:= First
(Component_Associations
(Aggr
));
11672 while Present
(Assoc
) loop
11673 Expr
:= Expression
(Assoc
);
11674 Resolve
(Expr
, Component_Type
(Typ
));
11676 -- For scalar array components set Do_Range_Check when
11677 -- needed. Constraint checking on non-scalar components
11678 -- is done in Aggregate_Constraint_Checks, but only if
11679 -- full analysis is enabled. These flags are not set in
11680 -- the front-end in GnatProve mode.
11682 if Is_Scalar_Type
(Component_Type
(Typ
))
11683 and then not Is_OK_Static_Expression
(Expr
)
11684 and then not Range_Checks_Suppressed
(Component_Type
(Typ
))
11686 if Is_Entity_Name
(Expr
)
11687 and then Etype
(Expr
) = Component_Type
(Typ
)
11692 Set_Do_Range_Check
(Expr
);
11696 -- The choices in the association are static constants,
11697 -- or static aggregates each of whose components belongs
11698 -- to the proper index type. However, they must also
11699 -- belong to the index subtype (s) of the prefix, which
11700 -- may be a subtype (e.g. given by a slice).
11702 -- Choices may also be identifiers with no staticness
11703 -- requirements, in which case they must resolve to the
11712 C
:= First
(Choices
(Assoc
));
11713 while Present
(C
) loop
11714 Indx
:= First_Index
(Etype
(Prefix
(N
)));
11716 if Nkind
(C
) /= N_Aggregate
then
11717 Analyze_And_Resolve
(C
, Etype
(Indx
));
11718 Apply_Constraint_Check
(C
, Etype
(Indx
));
11719 Check_Non_Static_Context
(C
);
11722 C_E
:= First
(Expressions
(C
));
11723 while Present
(C_E
) loop
11724 Analyze_And_Resolve
(C_E
, Etype
(Indx
));
11725 Apply_Constraint_Check
(C_E
, Etype
(Indx
));
11726 Check_Non_Static_Context
(C_E
);
11740 -- For a record type, use type of each component, which is
11741 -- recorded during analysis.
11744 Assoc
:= First
(Component_Associations
(Aggr
));
11745 while Present
(Assoc
) loop
11746 Comp
:= First
(Choices
(Assoc
));
11747 Expr
:= Expression
(Assoc
);
11749 if Nkind
(Comp
) /= N_Others_Choice
11750 and then not Error_Posted
(Comp
)
11752 Resolve
(Expr
, Etype
(Entity
(Comp
)));
11754 if Is_Scalar_Type
(Etype
(Entity
(Comp
)))
11755 and then not Is_OK_Static_Expression
(Expr
)
11756 and then not Range_Checks_Suppressed
11757 (Etype
(Entity
(Comp
)))
11759 Set_Do_Range_Check
(Expr
);
11772 -- Apply range check. Note that we did not do this during the
11773 -- analysis phase, since we wanted Eval_Attribute to have a
11774 -- chance at finding an illegal out of range value.
11776 when Attribute_Val
=>
11778 -- Note that we do our own Eval_Attribute call here rather than
11779 -- use the common one, because we need to do processing after
11780 -- the call, as per above comment.
11782 Eval_Attribute
(N
);
11784 -- Eval_Attribute may replace the node with a raise CE, or
11785 -- fold it to a constant. Obviously we only apply a scalar
11786 -- range check if this did not happen.
11788 if Nkind
(N
) = N_Attribute_Reference
11789 and then Attribute_Name
(N
) = Name_Val
11791 Apply_Scalar_Range_Check
(First
(Expressions
(N
)), Btyp
);
11800 -- Prefix of Version attribute can be a subprogram name which
11801 -- must not be resolved, since this is not a call.
11803 when Attribute_Version
=>
11806 ----------------------
11807 -- Other Attributes --
11808 ----------------------
11810 -- For other attributes, resolve prefix unless it is a type. If
11811 -- the attribute reference itself is a type name ('Base and 'Class)
11812 -- then this is only legal within a task or protected record.
11815 if not Is_Entity_Name
(P
) or else not Is_Type
(Entity
(P
)) then
11819 -- If the attribute reference itself is a type name ('Base,
11820 -- 'Class) then this is only legal within a task or protected
11821 -- record. What is this all about ???
11823 if Is_Entity_Name
(N
) and then Is_Type
(Entity
(N
)) then
11824 if Is_Concurrent_Type
(Entity
(N
))
11825 and then In_Open_Scopes
(Entity
(P
))
11830 ("invalid use of subtype name in expression or call", N
);
11834 -- For attributes whose argument may be a string, complete
11835 -- resolution of argument now. This avoids premature expansion
11836 -- (and the creation of transient scopes) before the attribute
11837 -- reference is resolved.
11840 when Attribute_Value
=>
11841 Resolve
(First
(Expressions
(N
)), Standard_String
);
11843 when Attribute_Wide_Value
=>
11844 Resolve
(First
(Expressions
(N
)), Standard_Wide_String
);
11846 when Attribute_Wide_Wide_Value
=>
11847 Resolve
(First
(Expressions
(N
)), Standard_Wide_Wide_String
);
11849 when others => null;
11852 -- If the prefix of the attribute is a class-wide type then it
11853 -- will be expanded into a dispatching call to a predefined
11854 -- primitive. Therefore we must check for potential violation
11855 -- of such restriction.
11857 if Is_Class_Wide_Type
(Etype
(P
)) then
11858 Check_Restriction
(No_Dispatching_Calls
, N
);
11862 -- Mark use clauses of the original prefix if the attribute is applied
11865 if Nkind
(Original_Node
(P
)) in N_Has_Entity
11866 and then Present
(Entity
(Original_Node
(P
)))
11868 Mark_Use_Clauses
(Original_Node
(P
));
11871 -- Normally the Freezing is done by Resolve but sometimes the Prefix
11872 -- is not resolved, in which case the freezing must be done now.
11874 -- For an elaboration check on a subprogram, we do not freeze its type.
11875 -- It may be declared in an unrelated scope, in particular in the case
11876 -- of a generic function whose type may remain unelaborated.
11878 if Attr_Id
= Attribute_Elaborated
then
11881 -- Should this be restricted to Expander_Active???
11884 Freeze_Expression
(P
);
11887 -- Finally perform static evaluation on the attribute reference
11889 Analyze_Dimension
(N
);
11890 Eval_Attribute
(N
);
11891 end Resolve_Attribute
;
11893 ------------------------
11894 -- Set_Boolean_Result --
11895 ------------------------
11897 procedure Set_Boolean_Result
(N
: Node_Id
; B
: Boolean) is
11898 Loc
: constant Source_Ptr
:= Sloc
(N
);
11901 Rewrite
(N
, New_Occurrence_Of
(Standard_True
, Loc
));
11903 Rewrite
(N
, New_Occurrence_Of
(Standard_False
, Loc
));
11905 end Set_Boolean_Result
;
11907 -------------------------------
11908 -- Statically_Denotes_Object --
11909 -------------------------------
11911 function Statically_Denotes_Object
(N
: Node_Id
) return Boolean is
11915 if Is_Entity_Name
(N
) then
11918 elsif Nkind
(N
) = N_Selected_Component
11919 and then Statically_Denotes_Object
(Prefix
(N
))
11920 and then Present
(Entity
(Selector_Name
(N
)))
11923 Sel_Id
: constant Entity_Id
:= Entity
(Selector_Name
(N
));
11924 Comp_Decl
: constant Node_Id
:= Parent
(Sel_Id
);
11927 if Depends_On_Discriminant
(Sel_Id
) then
11930 elsif Nkind
(Parent
(Parent
(Comp_Decl
))) = N_Variant
then
11938 elsif Nkind
(N
) = N_Indexed_Component
11939 and then Statically_Denotes_Object
(Prefix
(N
))
11940 and then Is_Constrained
(Etype
(Prefix
(N
)))
11942 Indx
:= First
(Expressions
(N
));
11943 while Present
(Indx
) loop
11944 if not Compile_Time_Known_Value
(Indx
)
11945 or else Do_Range_Check
(Indx
)
11958 end Statically_Denotes_Object
;
11960 --------------------------------
11961 -- Stream_Attribute_Available --
11962 --------------------------------
11964 function Stream_Attribute_Available
11966 Nam
: TSS_Name_Type
;
11967 Partial_View
: Node_Id
:= Empty
) return Boolean
11969 Etyp
: Entity_Id
:= Typ
;
11971 -- Start of processing for Stream_Attribute_Available
11974 -- We need some comments in this body ???
11976 if Has_Stream_Attribute_Definition
(Typ
, Nam
) then
11980 if Is_Class_Wide_Type
(Typ
) then
11981 return not Is_Limited_Type
(Typ
)
11982 or else Stream_Attribute_Available
(Etype
(Typ
), Nam
);
11985 if Nam
= TSS_Stream_Input
11986 and then Is_Abstract_Type
(Typ
)
11987 and then not Is_Class_Wide_Type
(Typ
)
11992 if not (Is_Limited_Type
(Typ
)
11993 or else (Present
(Partial_View
)
11994 and then Is_Limited_Type
(Partial_View
)))
11999 -- In Ada 2005, Input can invoke Read, and Output can invoke Write
12001 if Nam
= TSS_Stream_Input
12002 and then Ada_Version
>= Ada_2005
12003 and then Stream_Attribute_Available
(Etyp
, TSS_Stream_Read
)
12007 elsif Nam
= TSS_Stream_Output
12008 and then Ada_Version
>= Ada_2005
12009 and then Stream_Attribute_Available
(Etyp
, TSS_Stream_Write
)
12014 -- Case of Read and Write: check for attribute definition clause that
12015 -- applies to an ancestor type.
12017 while Etype
(Etyp
) /= Etyp
loop
12018 Etyp
:= Etype
(Etyp
);
12020 if Has_Stream_Attribute_Definition
(Etyp
, Nam
) then
12025 if Ada_Version
< Ada_2005
then
12027 -- In Ada 95 mode, also consider a non-visible definition
12030 Btyp
: constant Entity_Id
:= Implementation_Base_Type
(Typ
);
12033 and then Stream_Attribute_Available
12034 (Btyp
, Nam
, Partial_View
=> Typ
);
12039 end Stream_Attribute_Available
;