1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2014, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Ada
.Characters
.Latin_1
; use Ada
.Characters
.Latin_1
;
28 with Atree
; use Atree
;
29 with Casing
; use Casing
;
30 with Checks
; use Checks
;
31 with Debug
; use Debug
;
32 with Einfo
; use Einfo
;
33 with Elists
; use Elists
;
34 with Errout
; use Errout
;
36 with Exp_Dist
; use Exp_Dist
;
37 with Exp_Util
; use Exp_Util
;
38 with Expander
; use Expander
;
39 with Freeze
; use Freeze
;
40 with Gnatvsn
; use Gnatvsn
;
41 with Itypes
; use Itypes
;
43 with Lib
.Xref
; use Lib
.Xref
;
44 with Nlists
; use Nlists
;
45 with Nmake
; use Nmake
;
47 with Restrict
; use Restrict
;
48 with Rident
; use Rident
;
49 with Rtsfind
; use Rtsfind
;
50 with Sdefault
; use Sdefault
;
52 with Sem_Aux
; use Sem_Aux
;
53 with Sem_Cat
; use Sem_Cat
;
54 with Sem_Ch6
; use Sem_Ch6
;
55 with Sem_Ch8
; use Sem_Ch8
;
56 with Sem_Ch10
; use Sem_Ch10
;
57 with Sem_Dim
; use Sem_Dim
;
58 with Sem_Dist
; use Sem_Dist
;
59 with Sem_Elab
; use Sem_Elab
;
60 with Sem_Elim
; use Sem_Elim
;
61 with Sem_Eval
; use Sem_Eval
;
62 with Sem_Res
; use Sem_Res
;
63 with Sem_Type
; use Sem_Type
;
64 with Sem_Util
; use Sem_Util
;
65 with Stand
; use Stand
;
66 with Sinfo
; use Sinfo
;
67 with Sinput
; use Sinput
;
68 with Stringt
; use Stringt
;
70 with Stylesw
; use Stylesw
;
71 with Targparm
; use Targparm
;
72 with Ttypes
; use Ttypes
;
73 with Tbuild
; use Tbuild
;
74 with Uintp
; use Uintp
;
75 with Uname
; use Uname
;
76 with Urealp
; use Urealp
;
78 package body Sem_Attr
is
80 True_Value
: constant Uint
:= Uint_1
;
81 False_Value
: constant Uint
:= Uint_0
;
82 -- Synonyms to be used when these constants are used as Boolean values
84 Bad_Attribute
: exception;
85 -- Exception raised if an error is detected during attribute processing,
86 -- used so that we can abandon the processing so we don't run into
87 -- trouble with cascaded errors.
89 -- The following array is the list of attributes defined in the Ada 83 RM
90 -- that are not included in Ada 95, but still get recognized in GNAT.
92 Attribute_83
: constant Attribute_Class_Array
:= Attribute_Class_Array
'(
98 Attribute_Constrained |
105 Attribute_First_Bit |
111 Attribute_Leading_Part |
113 Attribute_Machine_Emax |
114 Attribute_Machine_Emin |
115 Attribute_Machine_Mantissa |
116 Attribute_Machine_Overflows |
117 Attribute_Machine_Radix |
118 Attribute_Machine_Rounds |
124 Attribute_Safe_Emax |
125 Attribute_Safe_Large |
126 Attribute_Safe_Small |
129 Attribute_Storage_Size |
131 Attribute_Terminated |
134 Attribute_Width => True,
137 -- The following array is the list of attributes defined in the Ada 2005
138 -- RM which are not defined in Ada 95. These are recognized in Ada 95 mode,
139 -- but in Ada 95 they are considered to be implementation defined.
141 Attribute_05 : constant Attribute_Class_Array := Attribute_Class_Array'(
142 Attribute_Machine_Rounding |
145 Attribute_Stream_Size |
146 Attribute_Wide_Wide_Width
=> True,
149 -- The following array contains all attributes that imply a modification
150 -- of their prefixes or result in an access value. Such prefixes can be
151 -- considered as lvalues.
153 Attribute_Name_Implies_Lvalue_Prefix
: constant Attribute_Class_Array
:=
154 Attribute_Class_Array
'(
159 Attribute_Unchecked_Access |
160 Attribute_Unrestricted_Access => True,
163 -----------------------
164 -- Local_Subprograms --
165 -----------------------
167 procedure Eval_Attribute (N : Node_Id);
168 -- Performs compile time evaluation of attributes where possible, leaving
169 -- the Is_Static_Expression/Raises_Constraint_Error flags appropriately
170 -- set, and replacing the node with a literal node if the value can be
171 -- computed at compile time. All static attribute references are folded,
172 -- as well as a number of cases of non-static attributes that can always
173 -- be computed at compile time (e.g. floating-point model attributes that
174 -- are applied to non-static subtypes). Of course in such cases, the
175 -- Is_Static_Expression flag will not be set on the resulting literal.
176 -- Note that the only required action of this procedure is to catch the
177 -- static expression cases as described in the RM. Folding of other cases
178 -- is done where convenient, but some additional non-static folding is in
179 -- Expand_N_Attribute_Reference in cases where this is more convenient.
181 function Is_Anonymous_Tagged_Base
185 -- For derived tagged types that constrain parent discriminants we build
186 -- an anonymous unconstrained base type. We need to recognize the relation
187 -- between the two when analyzing an access attribute for a constrained
188 -- component, before the full declaration for Typ has been analyzed, and
189 -- where therefore the prefix of the attribute does not match the enclosing
192 procedure Set_Boolean_Result (N : Node_Id; B : Boolean);
193 -- Rewrites node N with an occurrence of either Standard_False or
194 -- Standard_True, depending on the value of the parameter B. The
195 -- result is marked as a static expression.
197 -----------------------
198 -- Analyze_Attribute --
199 -----------------------
201 procedure Analyze_Attribute (N : Node_Id) is
202 Loc : constant Source_Ptr := Sloc (N);
203 Aname : constant Name_Id := Attribute_Name (N);
204 P : constant Node_Id := Prefix (N);
205 Exprs : constant List_Id := Expressions (N);
206 Attr_Id : constant Attribute_Id := Get_Attribute_Id (Aname);
211 -- Type of prefix after analysis
213 P_Base_Type : Entity_Id;
214 -- Base type of prefix after analysis
216 -----------------------
217 -- Local Subprograms --
218 -----------------------
220 procedure Address_Checks;
221 -- Semantic checks for valid use of Address attribute. This was made
222 -- a separate routine with the idea of using it for unrestricted access
223 -- which seems like it should follow the same rules, but that turned
224 -- out to be impractical. So now this is only used for Address.
226 procedure Analyze_Access_Attribute;
227 -- Used for Access, Unchecked_Access, Unrestricted_Access attributes.
228 -- Internally, Id distinguishes which of the three cases is involved.
230 procedure Bad_Attribute_For_Predicate;
231 -- Output error message for use of a predicate (First, Last, Range) not
232 -- allowed with a type that has predicates. If the type is a generic
233 -- actual, then the message is a warning, and we generate code to raise
234 -- program error with an appropriate reason. No error message is given
235 -- for internally generated uses of the attributes. This legality rule
236 -- only applies to scalar types.
238 procedure Check_Ada_2012_Attribute;
239 -- Check that we are in Ada 2012 mode for an Ada 2012 attribute, and
240 -- issue appropriate messages if not (and return to caller even in
243 procedure Check_Array_Or_Scalar_Type;
244 -- Common procedure used by First, Last, Range attribute to check
245 -- that the prefix is a constrained array or scalar type, or a name
246 -- of an array object, and that an argument appears only if appropriate
247 -- (i.e. only in the array case).
249 procedure Check_Array_Type;
250 -- Common semantic checks for all array attributes. Checks that the
251 -- prefix is a constrained array type or the name of an array object.
252 -- The error message for non-arrays is specialized appropriately.
254 procedure Check_Asm_Attribute;
255 -- Common semantic checks for Asm_Input and Asm_Output attributes
257 procedure Check_Component;
258 -- Common processing for Bit_Position, First_Bit, Last_Bit, and
259 -- Position. Checks prefix is an appropriate selected component.
261 procedure Check_Decimal_Fixed_Point_Type;
262 -- Check that prefix of attribute N is a decimal fixed-point type
264 procedure Check_Dereference;
265 -- If the prefix of attribute is an object of an access type, then
266 -- introduce an explicit dereference, and adjust P_Type accordingly.
268 procedure Check_Discrete_Type;
269 -- Verify that prefix of attribute N is a discrete type
272 -- Check that no attribute arguments are present
274 procedure Check_Either_E0_Or_E1;
275 -- Check that there are zero or one attribute arguments present
278 -- Check that exactly one attribute argument is present
281 -- Check that two attribute arguments are present
283 procedure Check_Enum_Image;
284 -- If the prefix type is an enumeration type, set all its literals
285 -- as referenced, since the image function could possibly end up
286 -- referencing any of the literals indirectly. Same for Enum_Val.
287 -- Set the flag only if the reference is in the main code unit. Same
288 -- restriction when resolving 'Value
; otherwise an improperly set
289 -- reference when analyzing an inlined body will lose a proper warning
290 -- on a useless with_clause.
292 procedure Check_First_Last_Valid
;
293 -- Perform all checks for First_Valid and Last_Valid attributes
295 procedure Check_Fixed_Point_Type
;
296 -- Verify that prefix of attribute N is a fixed type
298 procedure Check_Fixed_Point_Type_0
;
299 -- Verify that prefix of attribute N is a fixed type and that
300 -- no attribute expressions are present
302 procedure Check_Floating_Point_Type
;
303 -- Verify that prefix of attribute N is a float type
305 procedure Check_Floating_Point_Type_0
;
306 -- Verify that prefix of attribute N is a float type and that
307 -- no attribute expressions are present
309 procedure Check_Floating_Point_Type_1
;
310 -- Verify that prefix of attribute N is a float type and that
311 -- exactly one attribute expression is present
313 procedure Check_Floating_Point_Type_2
;
314 -- Verify that prefix of attribute N is a float type and that
315 -- two attribute expressions are present
317 procedure Check_SPARK_Restriction_On_Attribute
;
318 -- Issue an error in formal mode because attribute N is allowed
320 procedure Check_Integer_Type
;
321 -- Verify that prefix of attribute N is an integer type
323 procedure Check_Modular_Integer_Type
;
324 -- Verify that prefix of attribute N is a modular integer type
326 procedure Check_Not_CPP_Type
;
327 -- Check that P (the prefix of the attribute) is not an CPP type
328 -- for which no Ada predefined primitive is available.
330 procedure Check_Not_Incomplete_Type
;
331 -- Check that P (the prefix of the attribute) is not an incomplete
332 -- type or a private type for which no full view has been given.
334 procedure Check_Object_Reference
(P
: Node_Id
);
335 -- Check that P is an object reference
337 procedure Check_Program_Unit
;
338 -- Verify that prefix of attribute N is a program unit
340 procedure Check_Real_Type
;
341 -- Verify that prefix of attribute N is fixed or float type
343 procedure Check_Scalar_Type
;
344 -- Verify that prefix of attribute N is a scalar type
346 procedure Check_Standard_Prefix
;
347 -- Verify that prefix of attribute N is package Standard. Also checks
348 -- that there are no arguments.
350 procedure Check_Stream_Attribute
(Nam
: TSS_Name_Type
);
351 -- Validity checking for stream attribute. Nam is the TSS name of the
352 -- corresponding possible defined attribute function (e.g. for the
353 -- Read attribute, Nam will be TSS_Stream_Read).
355 procedure Check_System_Prefix
;
356 -- Verify that prefix of attribute N is package System
358 procedure Check_PolyORB_Attribute
;
359 -- Validity checking for PolyORB/DSA attribute
361 procedure Check_Task_Prefix
;
362 -- Verify that prefix of attribute N is a task or task type
364 procedure Check_Type
;
365 -- Verify that the prefix of attribute N is a type
367 procedure Check_Unit_Name
(Nod
: Node_Id
);
368 -- Check that Nod is of the form of a library unit name, i.e that
369 -- it is an identifier, or a selected component whose prefix is
370 -- itself of the form of a library unit name. Note that this is
371 -- quite different from Check_Program_Unit, since it only checks
372 -- the syntactic form of the name, not the semantic identity. This
373 -- is because it is used with attributes (Elab_Body, Elab_Spec,
374 -- UET_Address and Elaborated) which can refer to non-visible unit.
376 procedure Error_Attr
(Msg
: String; Error_Node
: Node_Id
);
377 pragma No_Return
(Error_Attr
);
378 procedure Error_Attr
;
379 pragma No_Return
(Error_Attr
);
380 -- Posts error using Error_Msg_N at given node, sets type of attribute
381 -- node to Any_Type, and then raises Bad_Attribute to avoid any further
382 -- semantic processing. The message typically contains a % insertion
383 -- character which is replaced by the attribute name. The call with
384 -- no arguments is used when the caller has already generated the
385 -- required error messages.
387 procedure Error_Attr_P
(Msg
: String);
388 pragma No_Return
(Error_Attr
);
389 -- Like Error_Attr, but error is posted at the start of the prefix
391 function In_Refined_Post
return Boolean;
392 -- Determine whether the current attribute appears in pragma
395 procedure Legal_Formal_Attribute
;
396 -- Common processing for attributes Definite and Has_Discriminants.
397 -- Checks that prefix is generic indefinite formal type.
399 procedure Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
;
400 -- Common processing for attributes Max_Alignment_For_Allocation and
401 -- Max_Size_In_Storage_Elements.
404 -- Common processing for attributes Max and Min
406 procedure Standard_Attribute
(Val
: Int
);
407 -- Used to process attributes whose prefix is package Standard which
408 -- yield values of type Universal_Integer. The attribute reference
409 -- node is rewritten with an integer literal of the given value.
411 procedure Unexpected_Argument
(En
: Node_Id
);
412 -- Signal unexpected attribute argument (En is the argument)
414 procedure Validate_Non_Static_Attribute_Function_Call
;
415 -- Called when processing an attribute that is a function call to a
416 -- non-static function, i.e. an attribute function that either takes
417 -- non-scalar arguments or returns a non-scalar result. Verifies that
418 -- such a call does not appear in a preelaborable context.
424 procedure Address_Checks
is
426 -- An Address attribute created by expansion is legal even when it
427 -- applies to other entity-denoting expressions.
429 if not Comes_From_Source
(N
) then
432 -- Address attribute on a protected object self reference is legal
434 elsif Is_Protected_Self_Reference
(P
) then
437 -- Address applied to an entity
439 elsif Is_Entity_Name
(P
) then
441 Ent
: constant Entity_Id
:= Entity
(P
);
444 if Is_Subprogram
(Ent
) then
445 Set_Address_Taken
(Ent
);
446 Kill_Current_Values
(Ent
);
448 -- An Address attribute is accepted when generated by the
449 -- compiler for dispatching operation, and an error is
450 -- issued once the subprogram is frozen (to avoid confusing
451 -- errors about implicit uses of Address in the dispatch
452 -- table initialization).
454 if Has_Pragma_Inline_Always
(Entity
(P
))
455 and then Comes_From_Source
(P
)
458 ("prefix of % attribute cannot be Inline_Always "
461 -- It is illegal to apply 'Address to an intrinsic
462 -- subprogram. This is now formalized in AI05-0095.
463 -- In an instance, an attempt to obtain 'Address of an
464 -- intrinsic subprogram (e.g the renaming of a predefined
465 -- operator that is an actual) raises Program_Error.
467 elsif Convention
(Ent
) = Convention_Intrinsic
then
470 Make_Raise_Program_Error
(Loc
,
471 Reason
=> PE_Address_Of_Intrinsic
));
474 Error_Msg_Name_1
:= Aname
;
476 ("cannot take % of intrinsic subprogram", N
);
479 -- Issue an error if prefix denotes an eliminated subprogram
482 Check_For_Eliminated_Subprogram
(P
, Ent
);
485 -- Object or label reference
487 elsif Is_Object
(Ent
) or else Ekind
(Ent
) = E_Label
then
488 Set_Address_Taken
(Ent
);
490 -- Deal with No_Implicit_Aliasing restriction
492 if Restriction_Check_Required
(No_Implicit_Aliasing
) then
493 if not Is_Aliased_View
(P
) then
494 Check_Restriction
(No_Implicit_Aliasing
, P
);
496 Check_No_Implicit_Aliasing
(P
);
500 -- If we have an address of an object, and the attribute
501 -- comes from source, then set the object as potentially
502 -- source modified. We do this because the resulting address
503 -- can potentially be used to modify the variable and we
504 -- might not detect this, leading to some junk warnings.
506 Set_Never_Set_In_Source
(Ent
, False);
508 -- Allow Address to be applied to task or protected type,
509 -- returning null address (what is that about???)
511 elsif (Is_Concurrent_Type
(Etype
(Ent
))
512 and then Etype
(Ent
) = Base_Type
(Ent
))
513 or else Ekind
(Ent
) = E_Package
514 or else Is_Generic_Unit
(Ent
)
517 New_Occurrence_Of
(RTE
(RE_Null_Address
), Sloc
(N
)));
519 -- Anything else is illegal
522 Error_Attr
("invalid prefix for % attribute", P
);
526 -- Allow Address if the prefix is a reference to the AST_Entry
527 -- attribute. If expansion is active, the attribute will be
528 -- replaced by a function call, and address will work fine and
529 -- get the proper value, but if expansion is not active, then
530 -- the check here allows proper semantic analysis of the reference.
532 elsif Nkind
(P
) = N_Attribute_Reference
533 and then Attribute_Name
(P
) = Name_AST_Entry
536 New_Occurrence_Of
(RTE
(RE_Null_Address
), Sloc
(N
)));
540 elsif Is_Object_Reference
(P
) then
543 -- Subprogram called using dot notation
545 elsif Nkind
(P
) = N_Selected_Component
546 and then Is_Subprogram
(Entity
(Selector_Name
(P
)))
550 -- What exactly are we allowing here ??? and is this properly
551 -- documented in the sinfo documentation for this node ???
553 elsif Relaxed_RM_Semantics
554 and then Nkind
(P
) = N_Attribute_Reference
558 -- All other non-entity name cases are illegal
561 Error_Attr
("invalid prefix for % attribute", P
);
565 ------------------------------
566 -- Analyze_Access_Attribute --
567 ------------------------------
569 procedure Analyze_Access_Attribute
is
570 Acc_Type
: Entity_Id
;
575 function Build_Access_Object_Type
(DT
: Entity_Id
) return Entity_Id
;
576 -- Build an access-to-object type whose designated type is DT,
577 -- and whose Ekind is appropriate to the attribute type. The
578 -- type that is constructed is returned as the result.
580 procedure Build_Access_Subprogram_Type
(P
: Node_Id
);
581 -- Build an access to subprogram whose designated type is the type of
582 -- the prefix. If prefix is overloaded, so is the node itself. The
583 -- result is stored in Acc_Type.
585 function OK_Self_Reference
return Boolean;
586 -- An access reference whose prefix is a type can legally appear
587 -- within an aggregate, where it is obtained by expansion of
588 -- a defaulted aggregate. The enclosing aggregate that contains
589 -- the self-referenced is flagged so that the self-reference can
590 -- be expanded into a reference to the target object (see exp_aggr).
592 ------------------------------
593 -- Build_Access_Object_Type --
594 ------------------------------
596 function Build_Access_Object_Type
(DT
: Entity_Id
) return Entity_Id
is
597 Typ
: constant Entity_Id
:=
599 (E_Access_Attribute_Type
, Current_Scope
, Loc
, 'A');
601 Set_Etype
(Typ
, Typ
);
603 Set_Associated_Node_For_Itype
(Typ
, N
);
604 Set_Directly_Designated_Type
(Typ
, DT
);
606 end Build_Access_Object_Type
;
608 ----------------------------------
609 -- Build_Access_Subprogram_Type --
610 ----------------------------------
612 procedure Build_Access_Subprogram_Type
(P
: Node_Id
) is
613 Index
: Interp_Index
;
616 procedure Check_Local_Access
(E
: Entity_Id
);
617 -- Deal with possible access to local subprogram. If we have such
618 -- an access, we set a flag to kill all tracked values on any call
619 -- because this access value may be passed around, and any called
620 -- code might use it to access a local procedure which clobbers a
621 -- tracked value. If the scope is a loop or block, indicate that
622 -- value tracking is disabled for the enclosing subprogram.
624 function Get_Kind
(E
: Entity_Id
) return Entity_Kind
;
625 -- Distinguish between access to regular/protected subprograms
627 ------------------------
628 -- Check_Local_Access --
629 ------------------------
631 procedure Check_Local_Access
(E
: Entity_Id
) is
633 if not Is_Library_Level_Entity
(E
) then
634 Set_Suppress_Value_Tracking_On_Call
(Current_Scope
);
635 Set_Suppress_Value_Tracking_On_Call
636 (Nearest_Dynamic_Scope
(Current_Scope
));
638 end Check_Local_Access
;
644 function Get_Kind
(E
: Entity_Id
) return Entity_Kind
is
646 if Convention
(E
) = Convention_Protected
then
647 return E_Access_Protected_Subprogram_Type
;
649 return E_Access_Subprogram_Type
;
653 -- Start of processing for Build_Access_Subprogram_Type
656 -- In the case of an access to subprogram, use the name of the
657 -- subprogram itself as the designated type. Type-checking in
658 -- this case compares the signatures of the designated types.
660 -- Note: This fragment of the tree is temporarily malformed
661 -- because the correct tree requires an E_Subprogram_Type entity
662 -- as the designated type. In most cases this designated type is
663 -- later overridden by the semantics with the type imposed by the
664 -- context during the resolution phase. In the specific case of
665 -- the expression Address!(Prim'Unrestricted_Access), used to
666 -- initialize slots of dispatch tables, this work will be done by
667 -- the expander (see Exp_Aggr).
669 -- The reason to temporarily add this kind of node to the tree
670 -- instead of a proper E_Subprogram_Type itype, is the following:
671 -- in case of errors found in the source file we report better
672 -- error messages. For example, instead of generating the
675 -- "expected access to subprogram with profile
676 -- defined at line X"
678 -- we currently generate:
680 -- "expected access to function Z defined at line X"
682 Set_Etype
(N
, Any_Type
);
684 if not Is_Overloaded
(P
) then
685 Check_Local_Access
(Entity
(P
));
687 if not Is_Intrinsic_Subprogram
(Entity
(P
)) then
688 Acc_Type
:= Create_Itype
(Get_Kind
(Entity
(P
)), N
);
689 Set_Is_Public
(Acc_Type
, False);
690 Set_Etype
(Acc_Type
, Acc_Type
);
691 Set_Convention
(Acc_Type
, Convention
(Entity
(P
)));
692 Set_Directly_Designated_Type
(Acc_Type
, Entity
(P
));
693 Set_Etype
(N
, Acc_Type
);
694 Freeze_Before
(N
, Acc_Type
);
698 Get_First_Interp
(P
, Index
, It
);
699 while Present
(It
.Nam
) loop
700 Check_Local_Access
(It
.Nam
);
702 if not Is_Intrinsic_Subprogram
(It
.Nam
) then
703 Acc_Type
:= Create_Itype
(Get_Kind
(It
.Nam
), N
);
704 Set_Is_Public
(Acc_Type
, False);
705 Set_Etype
(Acc_Type
, Acc_Type
);
706 Set_Convention
(Acc_Type
, Convention
(It
.Nam
));
707 Set_Directly_Designated_Type
(Acc_Type
, It
.Nam
);
708 Add_One_Interp
(N
, Acc_Type
, Acc_Type
);
709 Freeze_Before
(N
, Acc_Type
);
712 Get_Next_Interp
(Index
, It
);
716 -- Cannot be applied to intrinsic. Looking at the tests above,
717 -- the only way Etype (N) can still be set to Any_Type is if
718 -- Is_Intrinsic_Subprogram was True for some referenced entity.
720 if Etype
(N
) = Any_Type
then
721 Error_Attr_P
("prefix of % attribute cannot be intrinsic");
723 end Build_Access_Subprogram_Type
;
725 ----------------------
726 -- OK_Self_Reference --
727 ----------------------
729 function OK_Self_Reference
return Boolean is
736 (Nkind
(Par
) = N_Component_Association
737 or else Nkind
(Par
) in N_Subexpr
)
739 if Nkind_In
(Par
, N_Aggregate
, N_Extension_Aggregate
) then
740 if Etype
(Par
) = Typ
then
741 Set_Has_Self_Reference
(Par
);
749 -- No enclosing aggregate, or not a self-reference
752 end OK_Self_Reference
;
754 -- Start of processing for Analyze_Access_Attribute
757 Check_SPARK_Restriction_On_Attribute
;
760 if Nkind
(P
) = N_Character_Literal
then
762 ("prefix of % attribute cannot be enumeration literal");
765 -- Case of access to subprogram
767 if Is_Entity_Name
(P
)
768 and then Is_Overloadable
(Entity
(P
))
770 if Has_Pragma_Inline_Always
(Entity
(P
)) then
772 ("prefix of % attribute cannot be Inline_Always subprogram");
774 elsif Aname
= Name_Unchecked_Access
then
775 Error_Attr
("attribute% cannot be applied to a subprogram", P
);
777 elsif Is_Ghost_Subprogram
(Entity
(P
)) then
779 ("prefix of % attribute cannot be a ghost subprogram");
782 -- Issue an error if the prefix denotes an eliminated subprogram
784 Check_For_Eliminated_Subprogram
(P
, Entity
(P
));
786 -- Check for obsolescent subprogram reference
788 Check_Obsolescent_2005_Entity
(Entity
(P
), P
);
790 -- Build the appropriate subprogram type
792 Build_Access_Subprogram_Type
(P
);
794 -- For P'Access or P'Unrestricted_Access, where P is a nested
795 -- subprogram, we might be passing P to another subprogram (but we
796 -- don't check that here), which might call P. P could modify
797 -- local variables, so we need to kill current values. It is
798 -- important not to do this for library-level subprograms, because
799 -- Kill_Current_Values is very inefficient in the case of library
800 -- level packages with lots of tagged types.
802 if Is_Library_Level_Entity
(Entity
(Prefix
(N
))) then
805 -- Do not kill values on nodes initializing dispatch tables
806 -- slots. The construct Prim_Ptr!(Prim'Unrestricted_Access)
807 -- is currently generated by the expander only for this
808 -- purpose. Done to keep the quality of warnings currently
809 -- generated by the compiler (otherwise any declaration of
810 -- a tagged type cleans constant indications from its scope).
812 elsif Nkind
(Parent
(N
)) = N_Unchecked_Type_Conversion
813 and then (Etype
(Parent
(N
)) = RTE
(RE_Prim_Ptr
)
815 Etype
(Parent
(N
)) = RTE
(RE_Size_Ptr
))
816 and then Is_Dispatching_Operation
817 (Directly_Designated_Type
(Etype
(N
)))
825 -- In the static elaboration model, treat the attribute reference
826 -- as a call for elaboration purposes. Suppress this treatment
827 -- under debug flag. In any case, we are all done.
829 if not Dynamic_Elaboration_Checks
and not Debug_Flag_Dot_UU
then
835 -- Component is an operation of a protected type
837 elsif Nkind
(P
) = N_Selected_Component
838 and then Is_Overloadable
(Entity
(Selector_Name
(P
)))
840 if Ekind
(Entity
(Selector_Name
(P
))) = E_Entry
then
841 Error_Attr_P
("prefix of % attribute must be subprogram");
844 Build_Access_Subprogram_Type
(Selector_Name
(P
));
848 -- Deal with incorrect reference to a type, but note that some
849 -- accesses are allowed: references to the current type instance,
850 -- or in Ada 2005 self-referential pointer in a default-initialized
853 if Is_Entity_Name
(P
) then
856 -- The reference may appear in an aggregate that has been expanded
857 -- into a loop. Locate scope of type definition, if any.
859 Scop
:= Current_Scope
;
860 while Ekind
(Scop
) = E_Loop
loop
861 Scop
:= Scope
(Scop
);
864 if Is_Type
(Typ
) then
866 -- OK if we are within the scope of a limited type
867 -- let's mark the component as having per object constraint
869 if Is_Anonymous_Tagged_Base
(Scop
, Typ
) then
877 Q
: Node_Id
:= Parent
(N
);
881 and then Nkind
(Q
) /= N_Component_Declaration
887 Set_Has_Per_Object_Constraint
888 (Defining_Identifier
(Q
), True);
892 if Nkind
(P
) = N_Expanded_Name
then
894 ("current instance prefix must be a direct name", P
);
897 -- If a current instance attribute appears in a component
898 -- constraint it must appear alone; other contexts (spec-
899 -- expressions, within a task body) are not subject to this
902 if not In_Spec_Expression
903 and then not Has_Completion
(Scop
)
905 Nkind_In
(Parent
(N
), N_Discriminant_Association
,
906 N_Index_Or_Discriminant_Constraint
)
909 ("current instance attribute must appear alone", N
);
912 if Is_CPP_Class
(Root_Type
(Typ
)) then
914 ("??current instance unsupported for derivations of "
915 & "'C'P'P types", N
);
918 -- OK if we are in initialization procedure for the type
919 -- in question, in which case the reference to the type
920 -- is rewritten as a reference to the current object.
922 elsif Ekind
(Scop
) = E_Procedure
923 and then Is_Init_Proc
(Scop
)
924 and then Etype
(First_Formal
(Scop
)) = Typ
927 Make_Attribute_Reference
(Loc
,
928 Prefix
=> Make_Identifier
(Loc
, Name_uInit
),
929 Attribute_Name
=> Name_Unrestricted_Access
));
933 -- OK if a task type, this test needs sharpening up ???
935 elsif Is_Task_Type
(Typ
) then
938 -- OK if self-reference in an aggregate in Ada 2005, and
939 -- the reference comes from a copied default expression.
941 -- Note that we check legality of self-reference even if the
942 -- expression comes from source, e.g. when a single component
943 -- association in an aggregate has a box association.
945 elsif Ada_Version
>= Ada_2005
946 and then OK_Self_Reference
950 -- OK if reference to current instance of a protected object
952 elsif Is_Protected_Self_Reference
(P
) then
955 -- Otherwise we have an error case
958 Error_Attr
("% attribute cannot be applied to type", P
);
964 -- If we fall through, we have a normal access to object case.
965 -- Unrestricted_Access is legal wherever an allocator would be
966 -- legal, so its Etype is set to E_Allocator. The expected type
967 -- of the other attributes is a general access type, and therefore
968 -- we label them with E_Access_Attribute_Type.
970 if not Is_Overloaded
(P
) then
971 Acc_Type
:= Build_Access_Object_Type
(P_Type
);
972 Set_Etype
(N
, Acc_Type
);
975 Index
: Interp_Index
;
978 Set_Etype
(N
, Any_Type
);
979 Get_First_Interp
(P
, Index
, It
);
980 while Present
(It
.Typ
) loop
981 Acc_Type
:= Build_Access_Object_Type
(It
.Typ
);
982 Add_One_Interp
(N
, Acc_Type
, Acc_Type
);
983 Get_Next_Interp
(Index
, It
);
988 -- Special cases when we can find a prefix that is an entity name
997 if Is_Entity_Name
(PP
) then
1000 -- If we have an access to an object, and the attribute
1001 -- comes from source, then set the object as potentially
1002 -- source modified. We do this because the resulting access
1003 -- pointer can be used to modify the variable, and we might
1004 -- not detect this, leading to some junk warnings.
1006 Set_Never_Set_In_Source
(Ent
, False);
1008 -- Mark entity as address taken, and kill current values
1010 Set_Address_Taken
(Ent
);
1011 Kill_Current_Values
(Ent
);
1014 elsif Nkind_In
(PP
, N_Selected_Component
,
1015 N_Indexed_Component
)
1025 -- Check for aliased view unless unrestricted case. We allow a
1026 -- nonaliased prefix when within an instance because the prefix may
1027 -- have been a tagged formal object, which is defined to be aliased
1028 -- even when the actual might not be (other instance cases will have
1029 -- been caught in the generic). Similarly, within an inlined body we
1030 -- know that the attribute is legal in the original subprogram, and
1031 -- therefore legal in the expansion.
1033 if Aname
/= Name_Unrestricted_Access
1034 and then not Is_Aliased_View
(P
)
1035 and then not In_Instance
1036 and then not In_Inlined_Body
1038 Error_Attr_P
("prefix of % attribute must be aliased");
1039 Check_No_Implicit_Aliasing
(P
);
1041 end Analyze_Access_Attribute
;
1043 ---------------------------------
1044 -- Bad_Attribute_For_Predicate --
1045 ---------------------------------
1047 procedure Bad_Attribute_For_Predicate
is
1049 if Is_Scalar_Type
(P_Type
)
1050 and then Comes_From_Source
(N
)
1052 Error_Msg_Name_1
:= Aname
;
1053 Bad_Predicated_Subtype_Use
1054 ("type& has predicates, attribute % not allowed", N
, P_Type
);
1056 end Bad_Attribute_For_Predicate
;
1058 ------------------------------
1059 -- Check_Ada_2012_Attribute --
1060 ------------------------------
1062 procedure Check_Ada_2012_Attribute
is
1064 Error_Msg_Name_1
:= Aname
;
1065 Error_Msg_Ada_2012_Feature
("attribute %", Sloc
(N
));
1066 end Check_Ada_2012_Attribute
;
1068 --------------------------------
1069 -- Check_Array_Or_Scalar_Type --
1070 --------------------------------
1072 procedure Check_Array_Or_Scalar_Type
is
1076 -- Dimension number for array attributes
1079 -- Case of string literal or string literal subtype. These cases
1080 -- cannot arise from legal Ada code, but the expander is allowed
1081 -- to generate them. They require special handling because string
1082 -- literal subtypes do not have standard bounds (the whole idea
1083 -- of these subtypes is to avoid having to generate the bounds)
1085 if Ekind
(P_Type
) = E_String_Literal_Subtype
then
1086 Set_Etype
(N
, Etype
(First_Index
(P_Base_Type
)));
1091 elsif Is_Scalar_Type
(P_Type
) then
1094 if Present
(E1
) then
1095 Error_Attr
("invalid argument in % attribute", E1
);
1097 Set_Etype
(N
, P_Base_Type
);
1101 -- The following is a special test to allow 'First to apply to
1102 -- private scalar types if the attribute comes from generated
1103 -- code. This occurs in the case of Normalize_Scalars code.
1105 elsif Is_Private_Type
(P_Type
)
1106 and then Present
(Full_View
(P_Type
))
1107 and then Is_Scalar_Type
(Full_View
(P_Type
))
1108 and then not Comes_From_Source
(N
)
1110 Set_Etype
(N
, Implementation_Base_Type
(P_Type
));
1112 -- Array types other than string literal subtypes handled above
1117 -- We know prefix is an array type, or the name of an array
1118 -- object, and that the expression, if present, is static
1119 -- and within the range of the dimensions of the type.
1121 pragma Assert
(Is_Array_Type
(P_Type
));
1122 Index
:= First_Index
(P_Base_Type
);
1126 -- First dimension assumed
1128 Set_Etype
(N
, Base_Type
(Etype
(Index
)));
1131 D
:= UI_To_Int
(Intval
(E1
));
1133 for J
in 1 .. D
- 1 loop
1137 Set_Etype
(N
, Base_Type
(Etype
(Index
)));
1138 Set_Etype
(E1
, Standard_Integer
);
1141 end Check_Array_Or_Scalar_Type
;
1143 ----------------------
1144 -- Check_Array_Type --
1145 ----------------------
1147 procedure Check_Array_Type
is
1149 -- Dimension number for array attributes
1152 -- If the type is a string literal type, then this must be generated
1153 -- internally, and no further check is required on its legality.
1155 if Ekind
(P_Type
) = E_String_Literal_Subtype
then
1158 -- If the type is a composite, it is an illegal aggregate, no point
1161 elsif P_Type
= Any_Composite
then
1162 raise Bad_Attribute
;
1165 -- Normal case of array type or subtype
1167 Check_Either_E0_Or_E1
;
1170 if Is_Array_Type
(P_Type
) then
1171 if not Is_Constrained
(P_Type
)
1172 and then Is_Entity_Name
(P
)
1173 and then Is_Type
(Entity
(P
))
1175 -- Note: we do not call Error_Attr here, since we prefer to
1176 -- continue, using the relevant index type of the array,
1177 -- even though it is unconstrained. This gives better error
1178 -- recovery behavior.
1180 Error_Msg_Name_1
:= Aname
;
1182 ("prefix for % attribute must be constrained array", P
);
1185 -- The attribute reference freezes the type, and thus the
1186 -- component type, even if the attribute may not depend on the
1187 -- component. Diagnose arrays with incomplete components now.
1188 -- If the prefix is an access to array, this does not freeze
1189 -- the designated type.
1191 if Nkind
(P
) /= N_Explicit_Dereference
then
1192 Check_Fully_Declared
(Component_Type
(P_Type
), P
);
1195 D
:= Number_Dimensions
(P_Type
);
1198 if Is_Private_Type
(P_Type
) then
1199 Error_Attr_P
("prefix for % attribute may not be private type");
1201 elsif Is_Access_Type
(P_Type
)
1202 and then Is_Array_Type
(Designated_Type
(P_Type
))
1203 and then Is_Entity_Name
(P
)
1204 and then Is_Type
(Entity
(P
))
1206 Error_Attr_P
("prefix of % attribute cannot be access type");
1208 elsif Attr_Id
= Attribute_First
1210 Attr_Id
= Attribute_Last
1212 Error_Attr
("invalid prefix for % attribute", P
);
1215 Error_Attr_P
("prefix for % attribute must be array");
1219 if Present
(E1
) then
1220 Resolve
(E1
, Any_Integer
);
1221 Set_Etype
(E1
, Standard_Integer
);
1223 if not Is_Static_Expression
(E1
)
1224 or else Raises_Constraint_Error
(E1
)
1226 Flag_Non_Static_Expr
1227 ("expression for dimension must be static!", E1
);
1230 elsif UI_To_Int
(Expr_Value
(E1
)) > D
1231 or else UI_To_Int
(Expr_Value
(E1
)) < 1
1233 Error_Attr
("invalid dimension number for array type", E1
);
1237 if (Style_Check
and Style_Check_Array_Attribute_Index
)
1238 and then Comes_From_Source
(N
)
1240 Style
.Check_Array_Attribute_Index
(N
, E1
, D
);
1242 end Check_Array_Type
;
1244 -------------------------
1245 -- Check_Asm_Attribute --
1246 -------------------------
1248 procedure Check_Asm_Attribute
is
1253 -- Check first argument is static string expression
1255 Analyze_And_Resolve
(E1
, Standard_String
);
1257 if Etype
(E1
) = Any_Type
then
1260 elsif not Is_OK_Static_Expression
(E1
) then
1261 Flag_Non_Static_Expr
1262 ("constraint argument must be static string expression!", E1
);
1266 -- Check second argument is right type
1268 Analyze_And_Resolve
(E2
, Entity
(P
));
1270 -- Note: that is all we need to do, we don't need to check
1271 -- that it appears in a correct context. The Ada type system
1272 -- will do that for us.
1274 end Check_Asm_Attribute
;
1276 ---------------------
1277 -- Check_Component --
1278 ---------------------
1280 procedure Check_Component
is
1284 if Nkind
(P
) /= N_Selected_Component
1286 (Ekind
(Entity
(Selector_Name
(P
))) /= E_Component
1288 Ekind
(Entity
(Selector_Name
(P
))) /= E_Discriminant
)
1290 Error_Attr_P
("prefix for % attribute must be selected component");
1292 end Check_Component
;
1294 ------------------------------------
1295 -- Check_Decimal_Fixed_Point_Type --
1296 ------------------------------------
1298 procedure Check_Decimal_Fixed_Point_Type
is
1302 if not Is_Decimal_Fixed_Point_Type
(P_Type
) then
1303 Error_Attr_P
("prefix of % attribute must be decimal type");
1305 end Check_Decimal_Fixed_Point_Type
;
1307 -----------------------
1308 -- Check_Dereference --
1309 -----------------------
1311 procedure Check_Dereference
is
1314 -- Case of a subtype mark
1316 if Is_Entity_Name
(P
) and then Is_Type
(Entity
(P
)) then
1320 -- Case of an expression
1324 if Is_Access_Type
(P_Type
) then
1326 -- If there is an implicit dereference, then we must freeze the
1327 -- designated type of the access type, since the type of the
1328 -- referenced array is this type (see AI95-00106).
1330 -- As done elsewhere, freezing must not happen when pre-analyzing
1331 -- a pre- or postcondition or a default value for an object or for
1332 -- a formal parameter.
1334 if not In_Spec_Expression
then
1335 Freeze_Before
(N
, Designated_Type
(P_Type
));
1339 Make_Explicit_Dereference
(Sloc
(P
),
1340 Prefix
=> Relocate_Node
(P
)));
1342 Analyze_And_Resolve
(P
);
1343 P_Type
:= Etype
(P
);
1345 if P_Type
= Any_Type
then
1346 raise Bad_Attribute
;
1349 P_Base_Type
:= Base_Type
(P_Type
);
1351 end Check_Dereference
;
1353 -------------------------
1354 -- Check_Discrete_Type --
1355 -------------------------
1357 procedure Check_Discrete_Type
is
1361 if not Is_Discrete_Type
(P_Type
) then
1362 Error_Attr_P
("prefix of % attribute must be discrete type");
1364 end Check_Discrete_Type
;
1370 procedure Check_E0
is
1372 if Present
(E1
) then
1373 Unexpected_Argument
(E1
);
1381 procedure Check_E1
is
1383 Check_Either_E0_Or_E1
;
1387 -- Special-case attributes that are functions and that appear as
1388 -- the prefix of another attribute. Error is posted on parent.
1390 if Nkind
(Parent
(N
)) = N_Attribute_Reference
1391 and then Nam_In
(Attribute_Name
(Parent
(N
)), Name_Address
,
1395 Error_Msg_Name_1
:= Attribute_Name
(Parent
(N
));
1396 Error_Msg_N
("illegal prefix for % attribute", Parent
(N
));
1397 Set_Etype
(Parent
(N
), Any_Type
);
1398 Set_Entity
(Parent
(N
), Any_Type
);
1399 raise Bad_Attribute
;
1402 Error_Attr
("missing argument for % attribute", N
);
1411 procedure Check_E2
is
1414 Error_Attr
("missing arguments for % attribute (2 required)", N
);
1416 Error_Attr
("missing argument for % attribute (2 required)", N
);
1420 ---------------------------
1421 -- Check_Either_E0_Or_E1 --
1422 ---------------------------
1424 procedure Check_Either_E0_Or_E1
is
1426 if Present
(E2
) then
1427 Unexpected_Argument
(E2
);
1429 end Check_Either_E0_Or_E1
;
1431 ----------------------
1432 -- Check_Enum_Image --
1433 ----------------------
1435 procedure Check_Enum_Image
is
1439 -- When an enumeration type appears in an attribute reference, all
1440 -- literals of the type are marked as referenced. This must only be
1441 -- done if the attribute reference appears in the current source.
1442 -- Otherwise the information on references may differ between a
1443 -- normal compilation and one that performs inlining.
1445 if Is_Enumeration_Type
(P_Base_Type
)
1446 and then In_Extended_Main_Code_Unit
(N
)
1448 Lit
:= First_Literal
(P_Base_Type
);
1449 while Present
(Lit
) loop
1450 Set_Referenced
(Lit
);
1454 end Check_Enum_Image
;
1456 ----------------------------
1457 -- Check_First_Last_Valid --
1458 ----------------------------
1460 procedure Check_First_Last_Valid
is
1462 Check_Ada_2012_Attribute
;
1463 Check_Discrete_Type
;
1465 -- Freeze the subtype now, so that the following test for predicates
1466 -- works (we set the predicates stuff up at freeze time)
1468 Insert_Actions
(N
, Freeze_Entity
(P_Type
, P
));
1470 -- Now test for dynamic predicate
1472 if Has_Predicates
(P_Type
)
1473 and then No
(Static_Predicate
(P_Type
))
1476 ("prefix of % attribute may not have dynamic predicate");
1479 -- Check non-static subtype
1481 if not Is_Static_Subtype
(P_Type
) then
1482 Error_Attr_P
("prefix of % attribute must be a static subtype");
1485 -- Test case for no values
1487 if Expr_Value
(Type_Low_Bound
(P_Type
)) >
1488 Expr_Value
(Type_High_Bound
(P_Type
))
1489 or else (Has_Predicates
(P_Type
)
1490 and then Is_Empty_List
(Static_Predicate
(P_Type
)))
1493 ("prefix of % attribute must be subtype with "
1494 & "at least one value");
1496 end Check_First_Last_Valid
;
1498 ----------------------------
1499 -- Check_Fixed_Point_Type --
1500 ----------------------------
1502 procedure Check_Fixed_Point_Type
is
1506 if not Is_Fixed_Point_Type
(P_Type
) then
1507 Error_Attr_P
("prefix of % attribute must be fixed point type");
1509 end Check_Fixed_Point_Type
;
1511 ------------------------------
1512 -- Check_Fixed_Point_Type_0 --
1513 ------------------------------
1515 procedure Check_Fixed_Point_Type_0
is
1517 Check_Fixed_Point_Type
;
1519 end Check_Fixed_Point_Type_0
;
1521 -------------------------------
1522 -- Check_Floating_Point_Type --
1523 -------------------------------
1525 procedure Check_Floating_Point_Type
is
1529 if not Is_Floating_Point_Type
(P_Type
) then
1530 Error_Attr_P
("prefix of % attribute must be float type");
1532 end Check_Floating_Point_Type
;
1534 ---------------------------------
1535 -- Check_Floating_Point_Type_0 --
1536 ---------------------------------
1538 procedure Check_Floating_Point_Type_0
is
1540 Check_Floating_Point_Type
;
1542 end Check_Floating_Point_Type_0
;
1544 ---------------------------------
1545 -- Check_Floating_Point_Type_1 --
1546 ---------------------------------
1548 procedure Check_Floating_Point_Type_1
is
1550 Check_Floating_Point_Type
;
1552 end Check_Floating_Point_Type_1
;
1554 ---------------------------------
1555 -- Check_Floating_Point_Type_2 --
1556 ---------------------------------
1558 procedure Check_Floating_Point_Type_2
is
1560 Check_Floating_Point_Type
;
1562 end Check_Floating_Point_Type_2
;
1564 ------------------------
1565 -- Check_Integer_Type --
1566 ------------------------
1568 procedure Check_Integer_Type
is
1572 if not Is_Integer_Type
(P_Type
) then
1573 Error_Attr_P
("prefix of % attribute must be integer type");
1575 end Check_Integer_Type
;
1577 --------------------------------
1578 -- Check_Modular_Integer_Type --
1579 --------------------------------
1581 procedure Check_Modular_Integer_Type
is
1585 if not Is_Modular_Integer_Type
(P_Type
) then
1587 ("prefix of % attribute must be modular integer type");
1589 end Check_Modular_Integer_Type
;
1591 ------------------------
1592 -- Check_Not_CPP_Type --
1593 ------------------------
1595 procedure Check_Not_CPP_Type
is
1597 if Is_Tagged_Type
(Etype
(P
))
1598 and then Convention
(Etype
(P
)) = Convention_CPP
1599 and then Is_CPP_Class
(Root_Type
(Etype
(P
)))
1602 ("invalid use of % attribute with 'C'P'P tagged type");
1604 end Check_Not_CPP_Type
;
1606 -------------------------------
1607 -- Check_Not_Incomplete_Type --
1608 -------------------------------
1610 procedure Check_Not_Incomplete_Type
is
1615 -- Ada 2005 (AI-50217, AI-326): If the prefix is an explicit
1616 -- dereference we have to check wrong uses of incomplete types
1617 -- (other wrong uses are checked at their freezing point).
1619 -- Example 1: Limited-with
1621 -- limited with Pkg;
1623 -- type Acc is access Pkg.T;
1625 -- S : Integer := X.all'Size; -- ERROR
1628 -- Example 2: Tagged incomplete
1630 -- type T is tagged;
1631 -- type Acc is access all T;
1633 -- S : constant Integer := X.all'Size; -- ERROR
1634 -- procedure Q (Obj : Integer := X.all'Alignment); -- ERROR
1636 if Ada_Version
>= Ada_2005
1637 and then Nkind
(P
) = N_Explicit_Dereference
1640 while Nkind
(E
) = N_Explicit_Dereference
loop
1646 if From_Limited_With
(Typ
) then
1648 ("prefix of % attribute cannot be an incomplete type");
1651 if Is_Access_Type
(Typ
) then
1652 Typ
:= Directly_Designated_Type
(Typ
);
1655 if Is_Class_Wide_Type
(Typ
) then
1656 Typ
:= Root_Type
(Typ
);
1659 -- A legal use of a shadow entity occurs only when the unit
1660 -- where the non-limited view resides is imported via a regular
1661 -- with clause in the current body. Such references to shadow
1662 -- entities may occur in subprogram formals.
1664 if Is_Incomplete_Type
(Typ
)
1665 and then From_Limited_With
(Typ
)
1666 and then Present
(Non_Limited_View
(Typ
))
1667 and then Is_Legal_Shadow_Entity_In_Body
(Typ
)
1669 Typ
:= Non_Limited_View
(Typ
);
1672 if Ekind
(Typ
) = E_Incomplete_Type
1673 and then No
(Full_View
(Typ
))
1676 ("prefix of % attribute cannot be an incomplete type");
1681 if not Is_Entity_Name
(P
)
1682 or else not Is_Type
(Entity
(P
))
1683 or else In_Spec_Expression
1687 Check_Fully_Declared
(P_Type
, P
);
1689 end Check_Not_Incomplete_Type
;
1691 ----------------------------
1692 -- Check_Object_Reference --
1693 ----------------------------
1695 procedure Check_Object_Reference
(P
: Node_Id
) is
1699 -- If we need an object, and we have a prefix that is the name of
1700 -- a function entity, convert it into a function call.
1702 if Is_Entity_Name
(P
)
1703 and then Ekind
(Entity
(P
)) = E_Function
1705 Rtyp
:= Etype
(Entity
(P
));
1708 Make_Function_Call
(Sloc
(P
),
1709 Name
=> Relocate_Node
(P
)));
1711 Analyze_And_Resolve
(P
, Rtyp
);
1713 -- Otherwise we must have an object reference
1715 elsif not Is_Object_Reference
(P
) then
1716 Error_Attr_P
("prefix of % attribute must be object");
1718 end Check_Object_Reference
;
1720 ----------------------------
1721 -- Check_PolyORB_Attribute --
1722 ----------------------------
1724 procedure Check_PolyORB_Attribute
is
1726 Validate_Non_Static_Attribute_Function_Call
;
1731 if Get_PCS_Name
/= Name_PolyORB_DSA
then
1733 ("attribute% requires the 'Poly'O'R'B 'P'C'S", N
);
1735 end Check_PolyORB_Attribute
;
1737 ------------------------
1738 -- Check_Program_Unit --
1739 ------------------------
1741 procedure Check_Program_Unit
is
1743 if Is_Entity_Name
(P
) then
1745 K
: constant Entity_Kind
:= Ekind
(Entity
(P
));
1746 T
: constant Entity_Id
:= Etype
(Entity
(P
));
1749 if K
in Subprogram_Kind
1750 or else K
in Task_Kind
1751 or else K
in Protected_Kind
1752 or else K
= E_Package
1753 or else K
in Generic_Unit_Kind
1754 or else (K
= E_Variable
1758 Is_Protected_Type
(T
)))
1765 Error_Attr_P
("prefix of % attribute must be program unit");
1766 end Check_Program_Unit
;
1768 ---------------------
1769 -- Check_Real_Type --
1770 ---------------------
1772 procedure Check_Real_Type
is
1776 if not Is_Real_Type
(P_Type
) then
1777 Error_Attr_P
("prefix of % attribute must be real type");
1779 end Check_Real_Type
;
1781 -----------------------
1782 -- Check_Scalar_Type --
1783 -----------------------
1785 procedure Check_Scalar_Type
is
1789 if not Is_Scalar_Type
(P_Type
) then
1790 Error_Attr_P
("prefix of % attribute must be scalar type");
1792 end Check_Scalar_Type
;
1794 ------------------------------------------
1795 -- Check_SPARK_Restriction_On_Attribute --
1796 ------------------------------------------
1798 procedure Check_SPARK_Restriction_On_Attribute
is
1800 Error_Msg_Name_1
:= Aname
;
1801 Check_SPARK_Restriction
("attribute % is not allowed", P
);
1802 end Check_SPARK_Restriction_On_Attribute
;
1804 ---------------------------
1805 -- Check_Standard_Prefix --
1806 ---------------------------
1808 procedure Check_Standard_Prefix
is
1812 if Nkind
(P
) /= N_Identifier
or else Chars
(P
) /= Name_Standard
then
1813 Error_Attr
("only allowed prefix for % attribute is Standard", P
);
1815 end Check_Standard_Prefix
;
1817 ----------------------------
1818 -- Check_Stream_Attribute --
1819 ----------------------------
1821 procedure Check_Stream_Attribute
(Nam
: TSS_Name_Type
) is
1825 In_Shared_Var_Procs
: Boolean;
1826 -- True when compiling System.Shared_Storage.Shared_Var_Procs body.
1827 -- For this runtime package (always compiled in GNAT mode), we allow
1828 -- stream attributes references for limited types for the case where
1829 -- shared passive objects are implemented using stream attributes,
1830 -- which is the default in GNAT's persistent storage implementation.
1833 Validate_Non_Static_Attribute_Function_Call
;
1835 -- With the exception of 'Input, Stream attributes are procedures,
1836 -- and can only appear at the position of procedure calls. We check
1837 -- for this here, before they are rewritten, to give a more precise
1840 if Nam
= TSS_Stream_Input
then
1843 elsif Is_List_Member
(N
)
1844 and then not Nkind_In
(Parent
(N
), N_Procedure_Call_Statement
,
1851 ("invalid context for attribute%, which is a procedure", N
);
1855 Btyp
:= Implementation_Base_Type
(P_Type
);
1857 -- Stream attributes not allowed on limited types unless the
1858 -- attribute reference was generated by the expander (in which
1859 -- case the underlying type will be used, as described in Sinfo),
1860 -- or the attribute was specified explicitly for the type itself
1861 -- or one of its ancestors (taking visibility rules into account if
1862 -- in Ada 2005 mode), or a pragma Stream_Convert applies to Btyp
1863 -- (with no visibility restriction).
1866 Gen_Body
: constant Node_Id
:= Enclosing_Generic_Body
(N
);
1868 if Present
(Gen_Body
) then
1869 In_Shared_Var_Procs
:=
1870 Is_RTE
(Corresponding_Spec
(Gen_Body
), RE_Shared_Var_Procs
);
1872 In_Shared_Var_Procs
:= False;
1876 if (Comes_From_Source
(N
)
1877 and then not (In_Shared_Var_Procs
or In_Instance
))
1878 and then not Stream_Attribute_Available
(P_Type
, Nam
)
1879 and then not Has_Rep_Pragma
(Btyp
, Name_Stream_Convert
)
1881 Error_Msg_Name_1
:= Aname
;
1883 if Is_Limited_Type
(P_Type
) then
1885 ("limited type& has no% attribute", P
, P_Type
);
1886 Explain_Limited_Type
(P_Type
, P
);
1889 ("attribute% for type& is not available", P
, P_Type
);
1893 -- Check restriction violations
1895 -- First check the No_Streams restriction, which prohibits the use
1896 -- of explicit stream attributes in the source program. We do not
1897 -- prevent the occurrence of stream attributes in generated code,
1898 -- for instance those generated implicitly for dispatching purposes.
1900 if Comes_From_Source
(N
) then
1901 Check_Restriction
(No_Streams
, P
);
1904 -- AI05-0057: if restriction No_Default_Stream_Attributes is active,
1905 -- it is illegal to use a predefined elementary type stream attribute
1906 -- either by itself, or more importantly as part of the attribute
1907 -- subprogram for a composite type. However, if the broader
1908 -- restriction No_Streams is active, stream operations are not
1909 -- generated, and there is no error.
1911 if Restriction_Active
(No_Default_Stream_Attributes
)
1912 and then not Restriction_Active
(No_Streams
)
1918 if Nam
= TSS_Stream_Input
1920 Nam
= TSS_Stream_Read
1923 Type_Without_Stream_Operation
(P_Type
, TSS_Stream_Read
);
1926 Type_Without_Stream_Operation
(P_Type
, TSS_Stream_Write
);
1930 Check_Restriction
(No_Default_Stream_Attributes
, N
);
1933 ("missing user-defined Stream Read or Write for type&",
1935 if not Is_Elementary_Type
(P_Type
) then
1937 ("\which is a component of type&", N
, P_Type
);
1943 -- Check special case of Exception_Id and Exception_Occurrence which
1944 -- are not allowed for restriction No_Exception_Registration.
1946 if Restriction_Check_Required
(No_Exception_Registration
)
1947 and then (Is_RTE
(P_Type
, RE_Exception_Id
)
1949 Is_RTE
(P_Type
, RE_Exception_Occurrence
))
1951 Check_Restriction
(No_Exception_Registration
, P
);
1954 -- Here we must check that the first argument is an access type
1955 -- that is compatible with Ada.Streams.Root_Stream_Type'Class.
1957 Analyze_And_Resolve
(E1
);
1960 -- Note: the double call to Root_Type here is needed because the
1961 -- root type of a class-wide type is the corresponding type (e.g.
1962 -- X for X'Class, and we really want to go to the root.)
1964 if not Is_Access_Type
(Etyp
)
1965 or else Root_Type
(Root_Type
(Designated_Type
(Etyp
))) /=
1966 RTE
(RE_Root_Stream_Type
)
1969 ("expected access to Ada.Streams.Root_Stream_Type''Class", E1
);
1972 -- Check that the second argument is of the right type if there is
1973 -- one (the Input attribute has only one argument so this is skipped)
1975 if Present
(E2
) then
1978 if Nam
= TSS_Stream_Read
1979 and then not Is_OK_Variable_For_Out_Formal
(E2
)
1982 ("second argument of % attribute must be a variable", E2
);
1985 Resolve
(E2
, P_Type
);
1989 end Check_Stream_Attribute
;
1991 -------------------------
1992 -- Check_System_Prefix --
1993 -------------------------
1995 procedure Check_System_Prefix
is
1997 if Nkind
(P
) /= N_Identifier
or else Chars
(P
) /= Name_System
then
1998 Error_Attr
("only allowed prefix for % attribute is System", P
);
2000 end Check_System_Prefix
;
2002 -----------------------
2003 -- Check_Task_Prefix --
2004 -----------------------
2006 procedure Check_Task_Prefix
is
2010 -- Ada 2005 (AI-345): Attribute 'Terminated can be applied to
2011 -- task interface class-wide types.
2013 if Is_Task_Type
(Etype
(P
))
2014 or else (Is_Access_Type
(Etype
(P
))
2015 and then Is_Task_Type
(Designated_Type
(Etype
(P
))))
2016 or else (Ada_Version
>= Ada_2005
2017 and then Ekind
(Etype
(P
)) = E_Class_Wide_Type
2018 and then Is_Interface
(Etype
(P
))
2019 and then Is_Task_Interface
(Etype
(P
)))
2024 if Ada_Version
>= Ada_2005
then
2026 ("prefix of % attribute must be a task or a task " &
2027 "interface class-wide object");
2030 Error_Attr_P
("prefix of % attribute must be a task");
2033 end Check_Task_Prefix
;
2039 -- The possibilities are an entity name denoting a type, or an
2040 -- attribute reference that denotes a type (Base or Class). If
2041 -- the type is incomplete, replace it with its full view.
2043 procedure Check_Type
is
2045 if not Is_Entity_Name
(P
)
2046 or else not Is_Type
(Entity
(P
))
2048 Error_Attr_P
("prefix of % attribute must be a type");
2050 elsif Is_Protected_Self_Reference
(P
) then
2052 ("prefix of % attribute denotes current instance "
2053 & "(RM 9.4(21/2))");
2055 elsif Ekind
(Entity
(P
)) = E_Incomplete_Type
2056 and then Present
(Full_View
(Entity
(P
)))
2058 P_Type
:= Full_View
(Entity
(P
));
2059 Set_Entity
(P
, P_Type
);
2063 ---------------------
2064 -- Check_Unit_Name --
2065 ---------------------
2067 procedure Check_Unit_Name
(Nod
: Node_Id
) is
2069 if Nkind
(Nod
) = N_Identifier
then
2072 elsif Nkind_In
(Nod
, N_Selected_Component
, N_Expanded_Name
) then
2073 Check_Unit_Name
(Prefix
(Nod
));
2075 if Nkind
(Selector_Name
(Nod
)) = N_Identifier
then
2080 Error_Attr
("argument for % attribute must be unit name", P
);
2081 end Check_Unit_Name
;
2087 procedure Error_Attr
is
2089 Set_Etype
(N
, Any_Type
);
2090 Set_Entity
(N
, Any_Type
);
2091 raise Bad_Attribute
;
2094 procedure Error_Attr
(Msg
: String; Error_Node
: Node_Id
) is
2096 Error_Msg_Name_1
:= Aname
;
2097 Error_Msg_N
(Msg
, Error_Node
);
2105 procedure Error_Attr_P
(Msg
: String) is
2107 Error_Msg_Name_1
:= Aname
;
2108 Error_Msg_F
(Msg
, P
);
2112 ---------------------
2113 -- In_Refined_Post --
2114 ---------------------
2116 function In_Refined_Post
return Boolean is
2117 function Is_Refined_Post
(Prag
: Node_Id
) return Boolean;
2118 -- Determine whether Prag denotes one of the incarnations of pragma
2119 -- Refined_Post (either as is or pragma Check (Refined_Post, ...).
2121 ---------------------
2122 -- Is_Refined_Post --
2123 ---------------------
2125 function Is_Refined_Post
(Prag
: Node_Id
) return Boolean is
2126 Args
: constant List_Id
:= Pragma_Argument_Associations
(Prag
);
2127 Nam
: constant Name_Id
:= Pragma_Name
(Prag
);
2130 if Nam
= Name_Refined_Post
then
2133 elsif Nam
= Name_Check
then
2134 pragma Assert
(Present
(Args
));
2136 return Chars
(Expression
(First
(Args
))) = Name_Refined_Post
;
2140 end Is_Refined_Post
;
2146 -- Start of processing for In_Refined_Post
2150 while Present
(Stmt
) loop
2151 if Nkind
(Stmt
) = N_Pragma
and then Is_Refined_Post
(Stmt
) then
2154 -- Prevent the search from going too far
2156 elsif Is_Body_Or_Package_Declaration
(Stmt
) then
2160 Stmt
:= Parent
(Stmt
);
2164 end In_Refined_Post
;
2166 ----------------------------
2167 -- Legal_Formal_Attribute --
2168 ----------------------------
2170 procedure Legal_Formal_Attribute
is
2174 if not Is_Entity_Name
(P
)
2175 or else not Is_Type
(Entity
(P
))
2177 Error_Attr_P
("prefix of % attribute must be generic type");
2179 elsif Is_Generic_Actual_Type
(Entity
(P
))
2181 or else In_Inlined_Body
2185 elsif Is_Generic_Type
(Entity
(P
)) then
2186 if not Is_Indefinite_Subtype
(Entity
(P
)) then
2188 ("prefix of % attribute must be indefinite generic type");
2193 ("prefix of % attribute must be indefinite generic type");
2196 Set_Etype
(N
, Standard_Boolean
);
2197 end Legal_Formal_Attribute
;
2199 ---------------------------------------------------------------
2200 -- Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements --
2201 ---------------------------------------------------------------
2203 procedure Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
is
2207 Check_Not_Incomplete_Type
;
2208 Set_Etype
(N
, Universal_Integer
);
2209 end Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
;
2215 procedure Min_Max
is
2219 Resolve
(E1
, P_Base_Type
);
2220 Resolve
(E2
, P_Base_Type
);
2221 Set_Etype
(N
, P_Base_Type
);
2223 -- Check for comparison on unordered enumeration type
2225 if Bad_Unordered_Enumeration_Reference
(N
, P_Base_Type
) then
2226 Error_Msg_Sloc
:= Sloc
(P_Base_Type
);
2228 ("comparison on unordered enumeration type& declared#?U?",
2233 ------------------------
2234 -- Standard_Attribute --
2235 ------------------------
2237 procedure Standard_Attribute
(Val
: Int
) is
2239 Check_Standard_Prefix
;
2240 Rewrite
(N
, Make_Integer_Literal
(Loc
, Val
));
2242 end Standard_Attribute
;
2244 -------------------------
2245 -- Unexpected Argument --
2246 -------------------------
2248 procedure Unexpected_Argument
(En
: Node_Id
) is
2250 Error_Attr
("unexpected argument for % attribute", En
);
2251 end Unexpected_Argument
;
2253 -------------------------------------------------
2254 -- Validate_Non_Static_Attribute_Function_Call --
2255 -------------------------------------------------
2257 -- This function should be moved to Sem_Dist ???
2259 procedure Validate_Non_Static_Attribute_Function_Call
is
2261 if In_Preelaborated_Unit
2262 and then not In_Subprogram_Or_Concurrent_Unit
2264 Flag_Non_Static_Expr
2265 ("non-static function call in preelaborated unit!", N
);
2267 end Validate_Non_Static_Attribute_Function_Call
;
2269 -- Start of processing for Analyze_Attribute
2272 -- Immediate return if unrecognized attribute (already diagnosed
2273 -- by parser, so there is nothing more that we need to do)
2275 if not Is_Attribute_Name
(Aname
) then
2276 raise Bad_Attribute
;
2279 -- Deal with Ada 83 issues
2281 if Comes_From_Source
(N
) then
2282 if not Attribute_83
(Attr_Id
) then
2283 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
2284 Error_Msg_Name_1
:= Aname
;
2285 Error_Msg_N
("(Ada 83) attribute% is not standard??", N
);
2288 if Attribute_Impl_Def
(Attr_Id
) then
2289 Check_Restriction
(No_Implementation_Attributes
, N
);
2294 -- Deal with Ada 2005 attributes that are
2296 if Attribute_05
(Attr_Id
) and then Ada_Version
< Ada_2005
then
2297 Check_Restriction
(No_Implementation_Attributes
, N
);
2300 -- Remote access to subprogram type access attribute reference needs
2301 -- unanalyzed copy for tree transformation. The analyzed copy is used
2302 -- for its semantic information (whether prefix is a remote subprogram
2303 -- name), the unanalyzed copy is used to construct new subtree rooted
2304 -- with N_Aggregate which represents a fat pointer aggregate.
2306 if Aname
= Name_Access
then
2307 Discard_Node
(Copy_Separate_Tree
(N
));
2310 -- Analyze prefix and exit if error in analysis. If the prefix is an
2311 -- incomplete type, use full view if available. Note that there are
2312 -- some attributes for which we do not analyze the prefix, since the
2313 -- prefix is not a normal name, or else needs special handling.
2315 if Aname
/= Name_Elab_Body
and then
2316 Aname
/= Name_Elab_Spec
and then
2317 Aname
/= Name_Elab_Subp_Body
and then
2318 Aname
/= Name_UET_Address
and then
2319 Aname
/= Name_Enabled
and then
2323 P_Type
:= Etype
(P
);
2325 if Is_Entity_Name
(P
)
2326 and then Present
(Entity
(P
))
2327 and then Is_Type
(Entity
(P
))
2329 if Ekind
(Entity
(P
)) = E_Incomplete_Type
then
2330 P_Type
:= Get_Full_View
(P_Type
);
2331 Set_Entity
(P
, P_Type
);
2332 Set_Etype
(P
, P_Type
);
2334 elsif Entity
(P
) = Current_Scope
2335 and then Is_Record_Type
(Entity
(P
))
2337 -- Use of current instance within the type. Verify that if the
2338 -- attribute appears within a constraint, it yields an access
2339 -- type, other uses are illegal.
2347 and then Nkind
(Parent
(Par
)) /= N_Component_Definition
2349 Par
:= Parent
(Par
);
2353 and then Nkind
(Par
) = N_Subtype_Indication
2355 if Attr_Id
/= Attribute_Access
2356 and then Attr_Id
/= Attribute_Unchecked_Access
2357 and then Attr_Id
/= Attribute_Unrestricted_Access
2360 ("in a constraint the current instance can only"
2361 & " be used with an access attribute", N
);
2368 if P_Type
= Any_Type
then
2369 raise Bad_Attribute
;
2372 P_Base_Type
:= Base_Type
(P_Type
);
2375 -- Analyze expressions that may be present, exiting if an error occurs
2382 E1
:= First
(Exprs
);
2384 -- Skip analysis for case of Restriction_Set, we do not expect
2385 -- the argument to be analyzed in this case.
2387 if Aname
/= Name_Restriction_Set
then
2390 -- Check for missing/bad expression (result of previous error)
2392 if No
(E1
) or else Etype
(E1
) = Any_Type
then
2393 raise Bad_Attribute
;
2399 if Present
(E2
) then
2402 if Etype
(E2
) = Any_Type
then
2403 raise Bad_Attribute
;
2406 if Present
(Next
(E2
)) then
2407 Unexpected_Argument
(Next
(E2
));
2412 -- Cases where prefix must be resolvable by itself
2414 if Is_Overloaded
(P
)
2415 and then Aname
/= Name_Access
2416 and then Aname
/= Name_Address
2417 and then Aname
/= Name_Code_Address
2418 and then Aname
/= Name_Result
2419 and then Aname
/= Name_Unchecked_Access
2421 -- The prefix must be resolvable by itself, without reference to the
2422 -- attribute. One case that requires special handling is a prefix
2423 -- that is a function name, where one interpretation may be a
2424 -- parameterless call. Entry attributes are handled specially below.
2426 if Is_Entity_Name
(P
)
2427 and then not Nam_In
(Aname
, Name_Count
, Name_Caller
, Name_AST_Entry
)
2429 Check_Parameterless_Call
(P
);
2432 if Is_Overloaded
(P
) then
2434 -- Ada 2005 (AI-345): Since protected and task types have
2435 -- primitive entry wrappers, the attributes Count, Caller and
2436 -- AST_Entry require a context check
2438 if Nam_In
(Aname
, Name_Count
, Name_Caller
, Name_AST_Entry
) then
2440 Count
: Natural := 0;
2445 Get_First_Interp
(P
, I
, It
);
2446 while Present
(It
.Nam
) loop
2447 if Comes_From_Source
(It
.Nam
) then
2453 Get_Next_Interp
(I
, It
);
2457 Error_Attr
("ambiguous prefix for % attribute", P
);
2459 Set_Is_Overloaded
(P
, False);
2464 Error_Attr
("ambiguous prefix for % attribute", P
);
2469 -- In SPARK, attributes of private types are only allowed if the full
2470 -- type declaration is visible.
2472 -- Note: the check for Present (Entity (P)) defends against some error
2473 -- conditions where the Entity field is not set.
2475 if Is_Entity_Name
(P
) and then Present
(Entity
(P
))
2476 and then Is_Type
(Entity
(P
))
2477 and then Is_Private_Type
(P_Type
)
2478 and then not In_Open_Scopes
(Scope
(P_Type
))
2479 and then not In_Spec_Expression
2481 Check_SPARK_Restriction
("invisible attribute of type", N
);
2484 -- Remaining processing depends on attribute
2488 -- Attributes related to Ada 2012 iterators. Attribute specifications
2489 -- exist for these, but they cannot be queried.
2491 when Attribute_Constant_Indexing |
2492 Attribute_Default_Iterator |
2493 Attribute_Implicit_Dereference |
2494 Attribute_Iterator_Element |
2495 Attribute_Iterable |
2496 Attribute_Variable_Indexing
=>
2497 Error_Msg_N
("illegal attribute", N
);
2499 -- Internal attributes used to deal with Ada 2012 delayed aspects. These
2500 -- were already rejected by the parser. Thus they shouldn't appear here.
2502 when Internal_Attribute_Id
=>
2503 raise Program_Error
;
2509 when Attribute_Abort_Signal
=>
2510 Check_Standard_Prefix
;
2511 Rewrite
(N
, New_Occurrence_Of
(Stand
.Abort_Signal
, Loc
));
2518 when Attribute_Access
=>
2519 Analyze_Access_Attribute
;
2525 when Attribute_Address
=>
2528 Set_Etype
(N
, RTE
(RE_Address
));
2534 when Attribute_Address_Size
=>
2535 Standard_Attribute
(System_Address_Size
);
2541 when Attribute_Adjacent
=>
2542 Check_Floating_Point_Type_2
;
2543 Set_Etype
(N
, P_Base_Type
);
2544 Resolve
(E1
, P_Base_Type
);
2545 Resolve
(E2
, P_Base_Type
);
2551 when Attribute_Aft
=>
2552 Check_Fixed_Point_Type_0
;
2553 Set_Etype
(N
, Universal_Integer
);
2559 when Attribute_Alignment
=>
2561 -- Don't we need more checking here, cf Size ???
2564 Check_Not_Incomplete_Type
;
2566 Set_Etype
(N
, Universal_Integer
);
2572 when Attribute_Asm_Input
=>
2573 Check_Asm_Attribute
;
2575 -- The back-end may need to take the address of E2
2577 if Is_Entity_Name
(E2
) then
2578 Set_Address_Taken
(Entity
(E2
));
2581 Set_Etype
(N
, RTE
(RE_Asm_Input_Operand
));
2587 when Attribute_Asm_Output
=>
2588 Check_Asm_Attribute
;
2590 if Etype
(E2
) = Any_Type
then
2593 elsif Aname
= Name_Asm_Output
then
2594 if not Is_Variable
(E2
) then
2596 ("second argument for Asm_Output is not variable", E2
);
2600 Note_Possible_Modification
(E2
, Sure
=> True);
2602 -- The back-end may need to take the address of E2
2604 if Is_Entity_Name
(E2
) then
2605 Set_Address_Taken
(Entity
(E2
));
2608 Set_Etype
(N
, RTE
(RE_Asm_Output_Operand
));
2614 when Attribute_AST_Entry
=> AST_Entry
: declare
2620 -- Indicates if entry family index is present. Note the coding
2621 -- here handles the entry family case, but in fact it cannot be
2622 -- executed currently, because pragma AST_Entry does not permit
2623 -- the specification of an entry family.
2625 procedure Bad_AST_Entry
;
2626 -- Signal a bad AST_Entry pragma
2628 function OK_Entry
(E
: Entity_Id
) return Boolean;
2629 -- Checks that E is of an appropriate entity kind for an entry
2630 -- (i.e. E_Entry if Index is False, or E_Entry_Family if Index
2631 -- is set True for the entry family case). In the True case,
2632 -- makes sure that Is_AST_Entry is set on the entry.
2638 procedure Bad_AST_Entry
is
2640 Error_Attr_P
("prefix for % attribute must be task entry");
2647 function OK_Entry
(E
: Entity_Id
) return Boolean is
2652 Result
:= (Ekind
(E
) = E_Entry_Family
);
2654 Result
:= (Ekind
(E
) = E_Entry
);
2658 if not Is_AST_Entry
(E
) then
2659 Error_Msg_Name_2
:= Aname
;
2660 Error_Attr
("% attribute requires previous % pragma", P
);
2667 -- Start of processing for AST_Entry
2673 -- Deal with entry family case
2675 if Nkind
(P
) = N_Indexed_Component
then
2683 Ptyp
:= Etype
(Pref
);
2685 if Ptyp
= Any_Type
or else Error_Posted
(Pref
) then
2689 -- If the prefix is a selected component whose prefix is of an
2690 -- access type, then introduce an explicit dereference.
2691 -- ??? Could we reuse Check_Dereference here?
2693 if Nkind
(Pref
) = N_Selected_Component
2694 and then Is_Access_Type
(Ptyp
)
2697 Make_Explicit_Dereference
(Sloc
(Pref
),
2698 Relocate_Node
(Pref
)));
2699 Analyze_And_Resolve
(Pref
, Designated_Type
(Ptyp
));
2702 -- Prefix can be of the form a.b, where a is a task object
2703 -- and b is one of the entries of the corresponding task type.
2705 if Nkind
(Pref
) = N_Selected_Component
2706 and then OK_Entry
(Entity
(Selector_Name
(Pref
)))
2707 and then Is_Object_Reference
(Prefix
(Pref
))
2708 and then Is_Task_Type
(Etype
(Prefix
(Pref
)))
2712 -- Otherwise the prefix must be an entry of a containing task,
2713 -- or of a variable of the enclosing task type.
2716 if Nkind_In
(Pref
, N_Identifier
, N_Expanded_Name
) then
2717 Ent
:= Entity
(Pref
);
2719 if not OK_Entry
(Ent
)
2720 or else not In_Open_Scopes
(Scope
(Ent
))
2730 Set_Etype
(N
, RTE
(RE_AST_Handler
));
2733 -----------------------------
2734 -- Atomic_Always_Lock_Free --
2735 -----------------------------
2737 when Attribute_Atomic_Always_Lock_Free
=>
2740 Set_Etype
(N
, Standard_Boolean
);
2746 -- Note: when the base attribute appears in the context of a subtype
2747 -- mark, the analysis is done by Sem_Ch8.Find_Type, rather than by
2748 -- the following circuit.
2750 when Attribute_Base
=> Base
: declare
2758 if Ada_Version
>= Ada_95
2759 and then not Is_Scalar_Type
(Typ
)
2760 and then not Is_Generic_Type
(Typ
)
2762 Error_Attr_P
("prefix of Base attribute must be scalar type");
2764 elsif Sloc
(Typ
) = Standard_Location
2765 and then Base_Type
(Typ
) = Typ
2766 and then Warn_On_Redundant_Constructs
2768 Error_Msg_NE
-- CODEFIX
2769 ("?r?redundant attribute, & is its own base type", N
, Typ
);
2772 if Nkind
(Parent
(N
)) /= N_Attribute_Reference
then
2773 Error_Msg_Name_1
:= Aname
;
2774 Check_SPARK_Restriction
2775 ("attribute% is only allowed as prefix of another attribute", P
);
2778 Set_Etype
(N
, Base_Type
(Entity
(P
)));
2779 Set_Entity
(N
, Base_Type
(Entity
(P
)));
2780 Rewrite
(N
, New_Occurrence_Of
(Entity
(N
), Loc
));
2788 when Attribute_Bit
=> Bit
:
2792 if not Is_Object_Reference
(P
) then
2793 Error_Attr_P
("prefix for % attribute must be object");
2795 -- What about the access object cases ???
2801 Set_Etype
(N
, Universal_Integer
);
2808 when Attribute_Bit_Order
=> Bit_Order
:
2813 if not Is_Record_Type
(P_Type
) then
2814 Error_Attr_P
("prefix of % attribute must be record type");
2817 if Bytes_Big_Endian
xor Reverse_Bit_Order
(P_Type
) then
2819 New_Occurrence_Of
(RTE
(RE_High_Order_First
), Loc
));
2822 New_Occurrence_Of
(RTE
(RE_Low_Order_First
), Loc
));
2825 Set_Etype
(N
, RTE
(RE_Bit_Order
));
2828 -- Reset incorrect indication of staticness
2830 Set_Is_Static_Expression
(N
, False);
2837 -- Note: in generated code, we can have a Bit_Position attribute
2838 -- applied to a (naked) record component (i.e. the prefix is an
2839 -- identifier that references an E_Component or E_Discriminant
2840 -- entity directly, and this is interpreted as expected by Gigi.
2841 -- The following code will not tolerate such usage, but when the
2842 -- expander creates this special case, it marks it as analyzed
2843 -- immediately and sets an appropriate type.
2845 when Attribute_Bit_Position
=>
2846 if Comes_From_Source
(N
) then
2850 Set_Etype
(N
, Universal_Integer
);
2856 when Attribute_Body_Version
=>
2859 Set_Etype
(N
, RTE
(RE_Version_String
));
2865 when Attribute_Callable
=>
2867 Set_Etype
(N
, Standard_Boolean
);
2874 when Attribute_Caller
=> Caller
: declare
2881 if Nkind_In
(P
, N_Identifier
, N_Expanded_Name
) then
2884 if not Is_Entry
(Ent
) then
2885 Error_Attr
("invalid entry name", N
);
2889 Error_Attr
("invalid entry name", N
);
2893 for J
in reverse 0 .. Scope_Stack
.Last
loop
2894 S
:= Scope_Stack
.Table
(J
).Entity
;
2896 if S
= Scope
(Ent
) then
2897 Error_Attr
("Caller must appear in matching accept or body", N
);
2903 Set_Etype
(N
, RTE
(RO_AT_Task_Id
));
2910 when Attribute_Ceiling
=>
2911 Check_Floating_Point_Type_1
;
2912 Set_Etype
(N
, P_Base_Type
);
2913 Resolve
(E1
, P_Base_Type
);
2919 when Attribute_Class
=>
2920 Check_Restriction
(No_Dispatch
, N
);
2924 -- Applying Class to untagged incomplete type is obsolescent in Ada
2925 -- 2005. Note that we can't test Is_Tagged_Type here on P_Type, since
2926 -- this flag gets set by Find_Type in this situation.
2928 if Restriction_Check_Required
(No_Obsolescent_Features
)
2929 and then Ada_Version
>= Ada_2005
2930 and then Ekind
(P_Type
) = E_Incomplete_Type
2933 DN
: constant Node_Id
:= Declaration_Node
(P_Type
);
2935 if Nkind
(DN
) = N_Incomplete_Type_Declaration
2936 and then not Tagged_Present
(DN
)
2938 Check_Restriction
(No_Obsolescent_Features
, P
);
2947 when Attribute_Code_Address
=>
2950 if Nkind
(P
) = N_Attribute_Reference
2951 and then Nam_In
(Attribute_Name
(P
), Name_Elab_Body
, Name_Elab_Spec
)
2955 elsif not Is_Entity_Name
(P
)
2956 or else (Ekind
(Entity
(P
)) /= E_Function
2958 Ekind
(Entity
(P
)) /= E_Procedure
)
2960 Error_Attr
("invalid prefix for % attribute", P
);
2961 Set_Address_Taken
(Entity
(P
));
2963 -- Issue an error if the prefix denotes an eliminated subprogram
2966 Check_For_Eliminated_Subprogram
(P
, Entity
(P
));
2969 Set_Etype
(N
, RTE
(RE_Address
));
2971 ----------------------
2972 -- Compiler_Version --
2973 ----------------------
2975 when Attribute_Compiler_Version
=>
2977 Check_Standard_Prefix
;
2978 Rewrite
(N
, Make_String_Literal
(Loc
, "GNAT " & Gnat_Version_String
));
2979 Analyze_And_Resolve
(N
, Standard_String
);
2981 --------------------
2982 -- Component_Size --
2983 --------------------
2985 when Attribute_Component_Size
=>
2987 Set_Etype
(N
, Universal_Integer
);
2989 -- Note: unlike other array attributes, unconstrained arrays are OK
2991 if Is_Array_Type
(P_Type
) and then not Is_Constrained
(P_Type
) then
3001 when Attribute_Compose
=>
3002 Check_Floating_Point_Type_2
;
3003 Set_Etype
(N
, P_Base_Type
);
3004 Resolve
(E1
, P_Base_Type
);
3005 Resolve
(E2
, Any_Integer
);
3011 when Attribute_Constrained
=>
3013 Set_Etype
(N
, Standard_Boolean
);
3015 -- Case from RM J.4(2) of constrained applied to private type
3017 if Is_Entity_Name
(P
) and then Is_Type
(Entity
(P
)) then
3018 Check_Restriction
(No_Obsolescent_Features
, P
);
3020 if Warn_On_Obsolescent_Feature
then
3022 ("constrained for private type is an " &
3023 "obsolescent feature (RM J.4)?j?", N
);
3026 -- If we are within an instance, the attribute must be legal
3027 -- because it was valid in the generic unit. Ditto if this is
3028 -- an inlining of a function declared in an instance.
3031 or else In_Inlined_Body
3035 -- For sure OK if we have a real private type itself, but must
3036 -- be completed, cannot apply Constrained to incomplete type.
3038 elsif Is_Private_Type
(Entity
(P
)) then
3040 -- Note: this is one of the Annex J features that does not
3041 -- generate a warning from -gnatwj, since in fact it seems
3042 -- very useful, and is used in the GNAT runtime.
3044 Check_Not_Incomplete_Type
;
3048 -- Normal (non-obsolescent case) of application to object of
3049 -- a discriminated type.
3052 Check_Object_Reference
(P
);
3054 -- If N does not come from source, then we allow the
3055 -- the attribute prefix to be of a private type whose
3056 -- full type has discriminants. This occurs in cases
3057 -- involving expanded calls to stream attributes.
3059 if not Comes_From_Source
(N
) then
3060 P_Type
:= Underlying_Type
(P_Type
);
3063 -- Must have discriminants or be an access type designating
3064 -- a type with discriminants. If it is a classwide type it
3065 -- has unknown discriminants.
3067 if Has_Discriminants
(P_Type
)
3068 or else Has_Unknown_Discriminants
(P_Type
)
3070 (Is_Access_Type
(P_Type
)
3071 and then Has_Discriminants
(Designated_Type
(P_Type
)))
3075 -- The rule given in 3.7.2 is part of static semantics, but the
3076 -- intent is clearly that it be treated as a legality rule, and
3077 -- rechecked in the visible part of an instance. Nevertheless
3078 -- the intent also seems to be it should legally apply to the
3079 -- actual of a formal with unknown discriminants, regardless of
3080 -- whether the actual has discriminants, in which case the value
3081 -- of the attribute is determined using the J.4 rules. This choice
3082 -- seems the most useful, and is compatible with existing tests.
3084 elsif In_Instance
then
3087 -- Also allow an object of a generic type if extensions allowed
3088 -- and allow this for any type at all. (this may be obsolete ???)
3090 elsif (Is_Generic_Type
(P_Type
)
3091 or else Is_Generic_Actual_Type
(P_Type
))
3092 and then Extensions_Allowed
3098 -- Fall through if bad prefix
3101 ("prefix of % attribute must be object of discriminated type");
3107 when Attribute_Copy_Sign
=>
3108 Check_Floating_Point_Type_2
;
3109 Set_Etype
(N
, P_Base_Type
);
3110 Resolve
(E1
, P_Base_Type
);
3111 Resolve
(E2
, P_Base_Type
);
3117 when Attribute_Count
=> Count
:
3126 if Nkind_In
(P
, N_Identifier
, N_Expanded_Name
) then
3129 if Ekind
(Ent
) /= E_Entry
then
3130 Error_Attr
("invalid entry name", N
);
3133 elsif Nkind
(P
) = N_Indexed_Component
then
3134 if not Is_Entity_Name
(Prefix
(P
))
3135 or else No
(Entity
(Prefix
(P
)))
3136 or else Ekind
(Entity
(Prefix
(P
))) /= E_Entry_Family
3138 if Nkind
(Prefix
(P
)) = N_Selected_Component
3139 and then Present
(Entity
(Selector_Name
(Prefix
(P
))))
3140 and then Ekind
(Entity
(Selector_Name
(Prefix
(P
)))) =
3144 ("attribute % must apply to entry of current task", P
);
3147 Error_Attr
("invalid entry family name", P
);
3152 Ent
:= Entity
(Prefix
(P
));
3155 elsif Nkind
(P
) = N_Selected_Component
3156 and then Present
(Entity
(Selector_Name
(P
)))
3157 and then Ekind
(Entity
(Selector_Name
(P
))) = E_Entry
3160 ("attribute % must apply to entry of current task", P
);
3163 Error_Attr
("invalid entry name", N
);
3167 for J
in reverse 0 .. Scope_Stack
.Last
loop
3168 S
:= Scope_Stack
.Table
(J
).Entity
;
3170 if S
= Scope
(Ent
) then
3171 if Nkind
(P
) = N_Expanded_Name
then
3172 Tsk
:= Entity
(Prefix
(P
));
3174 -- The prefix denotes either the task type, or else a
3175 -- single task whose task type is being analyzed.
3180 or else (not Is_Type
(Tsk
)
3181 and then Etype
(Tsk
) = S
3182 and then not (Comes_From_Source
(S
)))
3187 ("Attribute % must apply to entry of current task", N
);
3193 elsif Ekind
(Scope
(Ent
)) in Task_Kind
3195 not Ekind_In
(S
, E_Loop
, E_Block
, E_Entry
, E_Entry_Family
)
3197 Error_Attr
("Attribute % cannot appear in inner unit", N
);
3199 elsif Ekind
(Scope
(Ent
)) = E_Protected_Type
3200 and then not Has_Completion
(Scope
(Ent
))
3202 Error_Attr
("attribute % can only be used inside body", N
);
3206 if Is_Overloaded
(P
) then
3208 Index
: Interp_Index
;
3212 Get_First_Interp
(P
, Index
, It
);
3214 while Present
(It
.Nam
) loop
3215 if It
.Nam
= Ent
then
3218 -- Ada 2005 (AI-345): Do not consider primitive entry
3219 -- wrappers generated for task or protected types.
3221 elsif Ada_Version
>= Ada_2005
3222 and then not Comes_From_Source
(It
.Nam
)
3227 Error_Attr
("ambiguous entry name", N
);
3230 Get_Next_Interp
(Index
, It
);
3235 Set_Etype
(N
, Universal_Integer
);
3238 -----------------------
3239 -- Default_Bit_Order --
3240 -----------------------
3242 when Attribute_Default_Bit_Order
=> Default_Bit_Order
:
3244 Check_Standard_Prefix
;
3246 if Bytes_Big_Endian
then
3248 Make_Integer_Literal
(Loc
, False_Value
));
3251 Make_Integer_Literal
(Loc
, True_Value
));
3254 Set_Etype
(N
, Universal_Integer
);
3255 Set_Is_Static_Expression
(N
);
3256 end Default_Bit_Order
;
3262 when Attribute_Definite
=>
3263 Legal_Formal_Attribute
;
3269 when Attribute_Delta
=>
3270 Check_Fixed_Point_Type_0
;
3271 Set_Etype
(N
, Universal_Real
);
3277 when Attribute_Denorm
=>
3278 Check_Floating_Point_Type_0
;
3279 Set_Etype
(N
, Standard_Boolean
);
3281 ---------------------
3282 -- Descriptor_Size --
3283 ---------------------
3285 when Attribute_Descriptor_Size
=>
3288 if not Is_Entity_Name
(P
)
3289 or else not Is_Type
(Entity
(P
))
3291 Error_Attr_P
("prefix of attribute % must denote a type");
3294 Set_Etype
(N
, Universal_Integer
);
3300 when Attribute_Digits
=>
3304 if not Is_Floating_Point_Type
(P_Type
)
3305 and then not Is_Decimal_Fixed_Point_Type
(P_Type
)
3308 ("prefix of % attribute must be float or decimal type");
3311 Set_Etype
(N
, Universal_Integer
);
3317 -- Also handles processing for Elab_Spec and Elab_Subp_Body
3319 when Attribute_Elab_Body |
3320 Attribute_Elab_Spec |
3321 Attribute_Elab_Subp_Body
=>
3324 Check_Unit_Name
(P
);
3325 Set_Etype
(N
, Standard_Void_Type
);
3327 -- We have to manually call the expander in this case to get
3328 -- the necessary expansion (normally attributes that return
3329 -- entities are not expanded).
3337 -- Shares processing with Elab_Body
3343 when Attribute_Elaborated
=>
3345 Check_Unit_Name
(P
);
3346 Set_Etype
(N
, Standard_Boolean
);
3352 when Attribute_Emax
=>
3353 Check_Floating_Point_Type_0
;
3354 Set_Etype
(N
, Universal_Integer
);
3360 when Attribute_Enabled
=>
3361 Check_Either_E0_Or_E1
;
3363 if Present
(E1
) then
3364 if not Is_Entity_Name
(E1
) or else No
(Entity
(E1
)) then
3365 Error_Msg_N
("entity name expected for Enabled attribute", E1
);
3370 if Nkind
(P
) /= N_Identifier
then
3371 Error_Msg_N
("identifier expected (check name)", P
);
3372 elsif Get_Check_Id
(Chars
(P
)) = No_Check_Id
then
3373 Error_Msg_N
("& is not a recognized check name", P
);
3376 Set_Etype
(N
, Standard_Boolean
);
3382 when Attribute_Enum_Rep
=> Enum_Rep
: declare
3384 if Present
(E1
) then
3386 Check_Discrete_Type
;
3387 Resolve
(E1
, P_Base_Type
);
3390 if not Is_Entity_Name
(P
)
3391 or else (not Is_Object
(Entity
(P
))
3393 Ekind
(Entity
(P
)) /= E_Enumeration_Literal
)
3396 ("prefix of % attribute must be " &
3397 "discrete type/object or enum literal");
3401 Set_Etype
(N
, Universal_Integer
);
3408 when Attribute_Enum_Val
=> Enum_Val
: begin
3412 if not Is_Enumeration_Type
(P_Type
) then
3413 Error_Attr_P
("prefix of % attribute must be enumeration type");
3416 -- If the enumeration type has a standard representation, the effect
3417 -- is the same as 'Val, so rewrite the attribute as a 'Val.
3419 if not Has_Non_Standard_Rep
(P_Base_Type
) then
3421 Make_Attribute_Reference
(Loc
,
3422 Prefix
=> Relocate_Node
(Prefix
(N
)),
3423 Attribute_Name
=> Name_Val
,
3424 Expressions
=> New_List
(Relocate_Node
(E1
))));
3425 Analyze_And_Resolve
(N
, P_Base_Type
);
3427 -- Non-standard representation case (enumeration with holes)
3431 Resolve
(E1
, Any_Integer
);
3432 Set_Etype
(N
, P_Base_Type
);
3440 when Attribute_Epsilon
=>
3441 Check_Floating_Point_Type_0
;
3442 Set_Etype
(N
, Universal_Real
);
3448 when Attribute_Exponent
=>
3449 Check_Floating_Point_Type_1
;
3450 Set_Etype
(N
, Universal_Integer
);
3451 Resolve
(E1
, P_Base_Type
);
3457 when Attribute_External_Tag
=>
3461 Set_Etype
(N
, Standard_String
);
3463 if not Is_Tagged_Type
(P_Type
) then
3464 Error_Attr_P
("prefix of % attribute must be tagged");
3471 when Attribute_Fast_Math
=>
3472 Check_Standard_Prefix
;
3473 Rewrite
(N
, New_Occurrence_Of
(Boolean_Literals
(Fast_Math
), Loc
));
3479 when Attribute_First
=>
3480 Check_Array_Or_Scalar_Type
;
3481 Bad_Attribute_For_Predicate
;
3487 when Attribute_First_Bit
=>
3489 Set_Etype
(N
, Universal_Integer
);
3495 when Attribute_First_Valid
=>
3496 Check_First_Last_Valid
;
3497 Set_Etype
(N
, P_Type
);
3503 when Attribute_Fixed_Value
=>
3505 Check_Fixed_Point_Type
;
3506 Resolve
(E1
, Any_Integer
);
3507 Set_Etype
(N
, P_Base_Type
);
3513 when Attribute_Floor
=>
3514 Check_Floating_Point_Type_1
;
3515 Set_Etype
(N
, P_Base_Type
);
3516 Resolve
(E1
, P_Base_Type
);
3522 when Attribute_Fore
=>
3523 Check_Fixed_Point_Type_0
;
3524 Set_Etype
(N
, Universal_Integer
);
3530 when Attribute_Fraction
=>
3531 Check_Floating_Point_Type_1
;
3532 Set_Etype
(N
, P_Base_Type
);
3533 Resolve
(E1
, P_Base_Type
);
3539 when Attribute_From_Any
=>
3541 Check_PolyORB_Attribute
;
3542 Set_Etype
(N
, P_Base_Type
);
3544 -----------------------
3545 -- Has_Access_Values --
3546 -----------------------
3548 when Attribute_Has_Access_Values
=>
3551 Set_Etype
(N
, Standard_Boolean
);
3553 -----------------------
3554 -- Has_Tagged_Values --
3555 -----------------------
3557 when Attribute_Has_Tagged_Values
=>
3560 Set_Etype
(N
, Standard_Boolean
);
3562 -----------------------
3563 -- Has_Discriminants --
3564 -----------------------
3566 when Attribute_Has_Discriminants
=>
3567 Legal_Formal_Attribute
;
3573 when Attribute_Identity
=>
3577 if Etype
(P
) = Standard_Exception_Type
then
3578 Set_Etype
(N
, RTE
(RE_Exception_Id
));
3580 -- Ada 2005 (AI-345): Attribute 'Identity may be applied to
3581 -- task interface class-wide types.
3583 elsif Is_Task_Type
(Etype
(P
))
3584 or else (Is_Access_Type
(Etype
(P
))
3585 and then Is_Task_Type
(Designated_Type
(Etype
(P
))))
3586 or else (Ada_Version
>= Ada_2005
3587 and then Ekind
(Etype
(P
)) = E_Class_Wide_Type
3588 and then Is_Interface
(Etype
(P
))
3589 and then Is_Task_Interface
(Etype
(P
)))
3592 Set_Etype
(N
, RTE
(RO_AT_Task_Id
));
3595 if Ada_Version
>= Ada_2005
then
3597 ("prefix of % attribute must be an exception, a " &
3598 "task or a task interface class-wide object");
3601 ("prefix of % attribute must be a task or an exception");
3609 when Attribute_Image
=> Image
:
3611 Check_SPARK_Restriction_On_Attribute
;
3613 Set_Etype
(N
, Standard_String
);
3615 if Is_Real_Type
(P_Type
) then
3616 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
3617 Error_Msg_Name_1
:= Aname
;
3619 ("(Ada 83) % attribute not allowed for real types", N
);
3623 if Is_Enumeration_Type
(P_Type
) then
3624 Check_Restriction
(No_Enumeration_Maps
, N
);
3628 Resolve
(E1
, P_Base_Type
);
3630 Validate_Non_Static_Attribute_Function_Call
;
3632 -- Check restriction No_Fixed_IO. Note the check of Comes_From_Source
3633 -- to avoid giving a duplicate message for Img expanded into Image.
3635 if Restriction_Check_Required
(No_Fixed_IO
)
3636 and then Comes_From_Source
(N
)
3637 and then Is_Fixed_Point_Type
(P_Type
)
3639 Check_Restriction
(No_Fixed_IO
, P
);
3647 when Attribute_Img
=> Img
:
3650 Set_Etype
(N
, Standard_String
);
3652 if not Is_Scalar_Type
(P_Type
)
3653 or else (Is_Entity_Name
(P
) and then Is_Type
(Entity
(P
)))
3656 ("prefix of % attribute must be scalar object name");
3661 -- Check restriction No_Fixed_IO
3663 if Restriction_Check_Required
(No_Fixed_IO
)
3664 and then Is_Fixed_Point_Type
(P_Type
)
3666 Check_Restriction
(No_Fixed_IO
, P
);
3674 when Attribute_Input
=>
3676 Check_Stream_Attribute
(TSS_Stream_Input
);
3677 Set_Etype
(N
, P_Base_Type
);
3683 when Attribute_Integer_Value
=>
3686 Resolve
(E1
, Any_Fixed
);
3688 -- Signal an error if argument type is not a specific fixed-point
3689 -- subtype. An error has been signalled already if the argument
3690 -- was not of a fixed-point type.
3692 if Etype
(E1
) = Any_Fixed
and then not Error_Posted
(E1
) then
3693 Error_Attr
("argument of % must be of a fixed-point type", E1
);
3696 Set_Etype
(N
, P_Base_Type
);
3702 when Attribute_Invalid_Value
=>
3705 Set_Etype
(N
, P_Base_Type
);
3706 Invalid_Value_Used
:= True;
3712 when Attribute_Large
=>
3715 Set_Etype
(N
, Universal_Real
);
3721 when Attribute_Last
=>
3722 Check_Array_Or_Scalar_Type
;
3723 Bad_Attribute_For_Predicate
;
3729 when Attribute_Last_Bit
=>
3731 Set_Etype
(N
, Universal_Integer
);
3737 when Attribute_Last_Valid
=>
3738 Check_First_Last_Valid
;
3739 Set_Etype
(N
, P_Type
);
3745 when Attribute_Leading_Part
=>
3746 Check_Floating_Point_Type_2
;
3747 Set_Etype
(N
, P_Base_Type
);
3748 Resolve
(E1
, P_Base_Type
);
3749 Resolve
(E2
, Any_Integer
);
3755 when Attribute_Length
=>
3757 Set_Etype
(N
, Universal_Integer
);
3763 when Attribute_Library_Level
=>
3766 if not Is_Entity_Name
(P
) then
3767 Error_Attr_P
("prefix of % attribute must be an entity name");
3770 if not Inside_A_Generic
then
3771 Set_Boolean_Result
(N
,
3772 Is_Library_Level_Entity
(Entity
(P
)));
3775 Set_Etype
(N
, Standard_Boolean
);
3781 when Attribute_Lock_Free
=>
3783 Set_Etype
(N
, Standard_Boolean
);
3785 if not Is_Protected_Type
(P_Type
) then
3787 ("prefix of % attribute must be a protected object");
3794 when Attribute_Loop_Entry
=> Loop_Entry
: declare
3795 procedure Check_References_In_Prefix
(Loop_Id
: Entity_Id
);
3796 -- Inspect the prefix for any uses of entities declared within the
3797 -- related loop. Loop_Id denotes the loop identifier.
3799 --------------------------------
3800 -- Check_References_In_Prefix --
3801 --------------------------------
3803 procedure Check_References_In_Prefix
(Loop_Id
: Entity_Id
) is
3804 Loop_Decl
: constant Node_Id
:= Label_Construct
(Parent
(Loop_Id
));
3806 function Check_Reference
(Nod
: Node_Id
) return Traverse_Result
;
3807 -- Determine whether a reference mentions an entity declared
3808 -- within the related loop.
3810 function Declared_Within
(Nod
: Node_Id
) return Boolean;
3811 -- Determine whether Nod appears in the subtree of Loop_Decl
3813 ---------------------
3814 -- Check_Reference --
3815 ---------------------
3817 function Check_Reference
(Nod
: Node_Id
) return Traverse_Result
is
3819 if Nkind
(Nod
) = N_Identifier
3820 and then Present
(Entity
(Nod
))
3821 and then Declared_Within
(Declaration_Node
(Entity
(Nod
)))
3824 ("prefix of attribute % cannot reference local entities",
3830 end Check_Reference
;
3832 procedure Check_References
is new Traverse_Proc
(Check_Reference
);
3834 ---------------------
3835 -- Declared_Within --
3836 ---------------------
3838 function Declared_Within
(Nod
: Node_Id
) return Boolean is
3843 while Present
(Stmt
) loop
3844 if Stmt
= Loop_Decl
then
3847 -- Prevent the search from going too far
3849 elsif Is_Body_Or_Package_Declaration
(Stmt
) then
3853 Stmt
:= Parent
(Stmt
);
3857 end Declared_Within
;
3859 -- Start of processing for Check_Prefix_For_Local_References
3862 Check_References
(P
);
3863 end Check_References_In_Prefix
;
3867 Context
: constant Node_Id
:= Parent
(N
);
3869 Enclosing_Loop
: Node_Id
;
3870 In_Loop_Assertion
: Boolean := False;
3871 Loop_Id
: Entity_Id
:= Empty
;
3875 -- Start of processing for Loop_Entry
3880 -- Set the type of the attribute now to ensure the successfull
3881 -- continuation of analysis even if the attribute is misplaced.
3883 Set_Etype
(Attr
, P_Type
);
3885 -- Attribute 'Loop_Entry may appear in several flavors:
3887 -- * Prefix'Loop_Entry - in this form, the attribute applies to the
3888 -- nearest enclosing loop.
3890 -- * Prefix'Loop_Entry (Expr) - depending on what Expr denotes, the
3891 -- attribute may be related to a loop denoted by label Expr or
3892 -- the prefix may denote an array object and Expr may act as an
3893 -- indexed component.
3895 -- * Prefix'Loop_Entry (Expr1, ..., ExprN) - the attribute applies
3896 -- to the nearest enclosing loop, all expressions are part of
3897 -- an indexed component.
3899 -- * Prefix'Loop_Entry (Expr) (...) (...) - depending on what Expr
3900 -- denotes, the attribute may be related to a loop denoted by
3901 -- label Expr or the prefix may denote a multidimensional array
3902 -- array object and Expr along with the rest of the expressions
3903 -- may act as indexed components.
3905 -- Regardless of variations, the attribute reference does not have an
3906 -- expression list. Instead, all available expressions are stored as
3907 -- indexed components.
3909 -- When the attribute is part of an indexed component, find the first
3910 -- expression as it will determine the semantics of 'Loop_Entry.
3912 if Nkind
(Context
) = N_Indexed_Component
then
3913 E1
:= First
(Expressions
(Context
));
3916 -- The attribute reference appears in the following form:
3918 -- Prefix'Loop_Entry (Exp1, Expr2, ..., ExprN) [(...)]
3920 -- In this case, the loop name is omitted and no rewriting is
3923 if Present
(E2
) then
3926 -- The form of the attribute is:
3928 -- Prefix'Loop_Entry (Expr) [(...)]
3930 -- If Expr denotes a loop entry, the whole attribute and indexed
3931 -- component will have to be rewritten to reflect this relation.
3934 pragma Assert
(Present
(E1
));
3936 -- Do not expand the expression as it may have side effects.
3937 -- Simply preanalyze to determine whether it is a loop name or
3940 Preanalyze_And_Resolve
(E1
);
3942 if Is_Entity_Name
(E1
)
3943 and then Present
(Entity
(E1
))
3944 and then Ekind
(Entity
(E1
)) = E_Loop
3946 Loop_Id
:= Entity
(E1
);
3948 -- Transform the attribute and enclosing indexed component
3950 Set_Expressions
(N
, Expressions
(Context
));
3951 Rewrite
(Context
, N
);
3952 Set_Etype
(Context
, P_Type
);
3959 -- The prefix must denote an object
3961 if not Is_Object_Reference
(P
) then
3962 Error_Attr_P
("prefix of attribute % must denote an object");
3965 -- The prefix cannot be of a limited type because the expansion of
3966 -- Loop_Entry must create a constant initialized by the evaluated
3969 if Is_Limited_View
(Etype
(P
)) then
3970 Error_Attr_P
("prefix of attribute % cannot be limited");
3973 -- Climb the parent chain to verify the location of the attribute and
3974 -- find the enclosing loop.
3977 while Present
(Stmt
) loop
3979 -- Locate the corresponding enclosing pragma. Note that in the
3980 -- case of Assert[And_Cut] and Assume, we have already checked
3981 -- that the pragma appears in an appropriate loop location.
3983 if Nkind
(Original_Node
(Stmt
)) = N_Pragma
3984 and then Nam_In
(Pragma_Name
(Original_Node
(Stmt
)),
3985 Name_Loop_Invariant
,
3988 Name_Assert_And_Cut
,
3991 In_Loop_Assertion
:= True;
3993 -- Locate the enclosing loop (if any). Note that Ada 2012 array
3994 -- iteration may be expanded into several nested loops, we are
3995 -- interested in the outermost one which has the loop identifier.
3997 elsif Nkind
(Stmt
) = N_Loop_Statement
3998 and then Present
(Identifier
(Stmt
))
4000 Enclosing_Loop
:= Stmt
;
4002 -- The original attribute reference may lack a loop name. Use
4003 -- the name of the enclosing loop because it is the related
4006 if No
(Loop_Id
) then
4007 Loop_Id
:= Entity
(Identifier
(Enclosing_Loop
));
4012 -- Prevent the search from going too far
4014 elsif Is_Body_Or_Package_Declaration
(Stmt
) then
4018 Stmt
:= Parent
(Stmt
);
4021 -- Loop_Entry must appear within a Loop_Assertion pragma (Assert,
4022 -- Assert_And_Cut, Assume count as loop assertion pragmas for this
4023 -- purpose if they appear in an appropriate location in a loop,
4024 -- which was already checked by the top level pragma circuit).
4026 if not In_Loop_Assertion
then
4028 ("attribute % must appear within appropriate pragma", N
);
4031 -- A Loop_Entry that applies to a given loop statement shall not
4032 -- appear within a body of accept statement, if this construct is
4033 -- itself enclosed by the given loop statement.
4035 for Index
in reverse 0 .. Scope_Stack
.Last
loop
4036 Scop
:= Scope_Stack
.Table
(Index
).Entity
;
4038 if Ekind
(Scop
) = E_Loop
and then Scop
= Loop_Id
then
4041 elsif Ekind_In
(Scop
, E_Block
, E_Loop
, E_Return_Statement
) then
4046 ("attribute % cannot appear in body or accept statement", N
);
4051 -- The prefix cannot mention entities declared within the related
4052 -- loop because they will not be visible once the prefix is moved
4053 -- outside the loop.
4055 Check_References_In_Prefix
(Loop_Id
);
4057 -- The prefix must denote a static entity if the pragma does not
4058 -- apply to the innermost enclosing loop statement, or if it appears
4059 -- within a potentially unevaluated epxression.
4061 if Is_Entity_Name
(P
)
4062 or else Nkind
(Parent
(P
)) = N_Object_Renaming_Declaration
4066 elsif Present
(Enclosing_Loop
)
4067 and then Entity
(Identifier
(Enclosing_Loop
)) /= Loop_Id
4069 Error_Attr_P
("prefix of attribute % that applies to "
4070 & "outer loop must denote an entity");
4072 elsif Is_Potentially_Unevaluated
(P
) then
4073 Error_Attr_P
("prefix of attribute % that is potentially "
4074 & "unevaluated must denote an entity");
4082 when Attribute_Machine
=>
4083 Check_Floating_Point_Type_1
;
4084 Set_Etype
(N
, P_Base_Type
);
4085 Resolve
(E1
, P_Base_Type
);
4091 when Attribute_Machine_Emax
=>
4092 Check_Floating_Point_Type_0
;
4093 Set_Etype
(N
, Universal_Integer
);
4099 when Attribute_Machine_Emin
=>
4100 Check_Floating_Point_Type_0
;
4101 Set_Etype
(N
, Universal_Integer
);
4103 ----------------------
4104 -- Machine_Mantissa --
4105 ----------------------
4107 when Attribute_Machine_Mantissa
=>
4108 Check_Floating_Point_Type_0
;
4109 Set_Etype
(N
, Universal_Integer
);
4111 -----------------------
4112 -- Machine_Overflows --
4113 -----------------------
4115 when Attribute_Machine_Overflows
=>
4118 Set_Etype
(N
, Standard_Boolean
);
4124 when Attribute_Machine_Radix
=>
4127 Set_Etype
(N
, Universal_Integer
);
4129 ----------------------
4130 -- Machine_Rounding --
4131 ----------------------
4133 when Attribute_Machine_Rounding
=>
4134 Check_Floating_Point_Type_1
;
4135 Set_Etype
(N
, P_Base_Type
);
4136 Resolve
(E1
, P_Base_Type
);
4138 --------------------
4139 -- Machine_Rounds --
4140 --------------------
4142 when Attribute_Machine_Rounds
=>
4145 Set_Etype
(N
, Standard_Boolean
);
4151 when Attribute_Machine_Size
=>
4154 Check_Not_Incomplete_Type
;
4155 Set_Etype
(N
, Universal_Integer
);
4161 when Attribute_Mantissa
=>
4164 Set_Etype
(N
, Universal_Integer
);
4170 when Attribute_Max
=>
4173 ----------------------------------
4174 -- Max_Alignment_For_Allocation --
4175 ----------------------------------
4177 when Attribute_Max_Size_In_Storage_Elements
=>
4178 Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
;
4180 ----------------------------------
4181 -- Max_Size_In_Storage_Elements --
4182 ----------------------------------
4184 when Attribute_Max_Alignment_For_Allocation
=>
4185 Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
;
4187 -----------------------
4188 -- Maximum_Alignment --
4189 -----------------------
4191 when Attribute_Maximum_Alignment
=>
4192 Standard_Attribute
(Ttypes
.Maximum_Alignment
);
4194 --------------------
4195 -- Mechanism_Code --
4196 --------------------
4198 when Attribute_Mechanism_Code
=>
4199 if not Is_Entity_Name
(P
)
4200 or else not Is_Subprogram
(Entity
(P
))
4202 Error_Attr_P
("prefix of % attribute must be subprogram");
4205 Check_Either_E0_Or_E1
;
4207 if Present
(E1
) then
4208 Resolve
(E1
, Any_Integer
);
4209 Set_Etype
(E1
, Standard_Integer
);
4211 if not Is_Static_Expression
(E1
) then
4212 Flag_Non_Static_Expr
4213 ("expression for parameter number must be static!", E1
);
4216 elsif UI_To_Int
(Intval
(E1
)) > Number_Formals
(Entity
(P
))
4217 or else UI_To_Int
(Intval
(E1
)) < 0
4219 Error_Attr
("invalid parameter number for % attribute", E1
);
4223 Set_Etype
(N
, Universal_Integer
);
4229 when Attribute_Min
=>
4236 when Attribute_Mod
=>
4238 -- Note: this attribute is only allowed in Ada 2005 mode, but
4239 -- we do not need to test that here, since Mod is only recognized
4240 -- as an attribute name in Ada 2005 mode during the parse.
4243 Check_Modular_Integer_Type
;
4244 Resolve
(E1
, Any_Integer
);
4245 Set_Etype
(N
, P_Base_Type
);
4251 when Attribute_Model
=>
4252 Check_Floating_Point_Type_1
;
4253 Set_Etype
(N
, P_Base_Type
);
4254 Resolve
(E1
, P_Base_Type
);
4260 when Attribute_Model_Emin
=>
4261 Check_Floating_Point_Type_0
;
4262 Set_Etype
(N
, Universal_Integer
);
4268 when Attribute_Model_Epsilon
=>
4269 Check_Floating_Point_Type_0
;
4270 Set_Etype
(N
, Universal_Real
);
4272 --------------------
4273 -- Model_Mantissa --
4274 --------------------
4276 when Attribute_Model_Mantissa
=>
4277 Check_Floating_Point_Type_0
;
4278 Set_Etype
(N
, Universal_Integer
);
4284 when Attribute_Model_Small
=>
4285 Check_Floating_Point_Type_0
;
4286 Set_Etype
(N
, Universal_Real
);
4292 when Attribute_Modulus
=>
4294 Check_Modular_Integer_Type
;
4295 Set_Etype
(N
, Universal_Integer
);
4297 --------------------
4298 -- Null_Parameter --
4299 --------------------
4301 when Attribute_Null_Parameter
=> Null_Parameter
: declare
4302 Parnt
: constant Node_Id
:= Parent
(N
);
4303 GParnt
: constant Node_Id
:= Parent
(Parnt
);
4305 procedure Bad_Null_Parameter
(Msg
: String);
4306 -- Used if bad Null parameter attribute node is found. Issues
4307 -- given error message, and also sets the type to Any_Type to
4308 -- avoid blowups later on from dealing with a junk node.
4310 procedure Must_Be_Imported
(Proc_Ent
: Entity_Id
);
4311 -- Called to check that Proc_Ent is imported subprogram
4313 ------------------------
4314 -- Bad_Null_Parameter --
4315 ------------------------
4317 procedure Bad_Null_Parameter
(Msg
: String) is
4319 Error_Msg_N
(Msg
, N
);
4320 Set_Etype
(N
, Any_Type
);
4321 end Bad_Null_Parameter
;
4323 ----------------------
4324 -- Must_Be_Imported --
4325 ----------------------
4327 procedure Must_Be_Imported
(Proc_Ent
: Entity_Id
) is
4328 Pent
: constant Entity_Id
:= Ultimate_Alias
(Proc_Ent
);
4331 -- Ignore check if procedure not frozen yet (we will get
4332 -- another chance when the default parameter is reanalyzed)
4334 if not Is_Frozen
(Pent
) then
4337 elsif not Is_Imported
(Pent
) then
4339 ("Null_Parameter can only be used with imported subprogram");
4344 end Must_Be_Imported
;
4346 -- Start of processing for Null_Parameter
4351 Set_Etype
(N
, P_Type
);
4353 -- Case of attribute used as default expression
4355 if Nkind
(Parnt
) = N_Parameter_Specification
then
4356 Must_Be_Imported
(Defining_Entity
(GParnt
));
4358 -- Case of attribute used as actual for subprogram (positional)
4360 elsif Nkind
(Parnt
) in N_Subprogram_Call
4361 and then Is_Entity_Name
(Name
(Parnt
))
4363 Must_Be_Imported
(Entity
(Name
(Parnt
)));
4365 -- Case of attribute used as actual for subprogram (named)
4367 elsif Nkind
(Parnt
) = N_Parameter_Association
4368 and then Nkind
(GParnt
) in N_Subprogram_Call
4369 and then Is_Entity_Name
(Name
(GParnt
))
4371 Must_Be_Imported
(Entity
(Name
(GParnt
)));
4373 -- Not an allowed case
4377 ("Null_Parameter must be actual or default parameter");
4385 when Attribute_Object_Size
=>
4388 Check_Not_Incomplete_Type
;
4389 Set_Etype
(N
, Universal_Integer
);
4395 when Attribute_Old
=> Old
: declare
4396 procedure Check_References_In_Prefix
(Subp_Id
: Entity_Id
);
4397 -- Inspect the contents of the prefix and detect illegal uses of a
4398 -- nested 'Old, attribute 'Result or a use of an entity declared in
4399 -- the related postcondition expression. Subp_Id is the subprogram to
4400 -- which the related postcondition applies.
4402 procedure Check_Use_In_Contract_Cases
(Prag
: Node_Id
);
4403 -- Perform various semantic checks related to the placement of the
4404 -- attribute in pragma Contract_Cases.
4406 procedure Check_Use_In_Test_Case
(Prag
: Node_Id
);
4407 -- Perform various semantic checks related to the placement of the
4408 -- attribute in pragma Contract_Cases.
4410 --------------------------------
4411 -- Check_References_In_Prefix --
4412 --------------------------------
4414 procedure Check_References_In_Prefix
(Subp_Id
: Entity_Id
) is
4415 function Check_Reference
(Nod
: Node_Id
) return Traverse_Result
;
4416 -- Detect attribute 'Old, attribute 'Result of a use of an entity
4417 -- and perform the appropriate semantic check.
4419 ---------------------
4420 -- Check_Reference --
4421 ---------------------
4423 function Check_Reference
(Nod
: Node_Id
) return Traverse_Result
is
4425 -- Attributes 'Old and 'Result cannot appear in the prefix of
4426 -- another attribute 'Old.
4428 if Nkind
(Nod
) = N_Attribute_Reference
4429 and then Nam_In
(Attribute_Name
(Nod
), Name_Old
,
4432 Error_Msg_Name_1
:= Attribute_Name
(Nod
);
4433 Error_Msg_Name_2
:= Name_Old
;
4435 ("attribute % cannot appear in the prefix of attribute %",
4439 -- Entities mentioned within the prefix of attribute 'Old must
4440 -- be global to the related postcondition. If this is not the
4441 -- case, then the scope of the local entity is nested within
4442 -- that of the subprogram.
4444 elsif Nkind
(Nod
) = N_Identifier
4445 and then Present
(Entity
(Nod
))
4446 and then Scope_Within
(Scope
(Entity
(Nod
)), Subp_Id
)
4449 ("prefix of attribute % cannot reference local entities",
4455 end Check_Reference
;
4457 procedure Check_References
is new Traverse_Proc
(Check_Reference
);
4459 -- Start of processing for Check_References_In_Prefix
4462 Check_References
(P
);
4463 end Check_References_In_Prefix
;
4465 ---------------------------------
4466 -- Check_Use_In_Contract_Cases --
4467 ---------------------------------
4469 procedure Check_Use_In_Contract_Cases
(Prag
: Node_Id
) is
4470 Cases
: constant Node_Id
:=
4472 (First
(Pragma_Argument_Associations
(Prag
)));
4476 -- Climb the parent chain to reach the top of the expression where
4477 -- attribute 'Old resides.
4480 while Parent
(Parent
(Expr
)) /= Cases
loop
4481 Expr
:= Parent
(Expr
);
4484 -- Ensure that the obtained expression is the consequence of a
4485 -- contract case as this is the only postcondition-like part of
4488 if Expr
= Expression
(Parent
(Expr
)) then
4490 -- Warn that a potentially unevaluated prefix is always
4491 -- evaluated when the corresponding consequence is selected.
4493 if Is_Potentially_Unevaluated
(P
) then
4494 Error_Msg_Name_1
:= Aname
;
4496 ("??prefix of attribute % is always evaluated when "
4497 & "related consequence is selected", P
);
4500 -- Attribute 'Old appears in the condition of a contract case.
4501 -- Emit an error since this is not a postcondition-like context.
4502 -- (SPARK RM 6.1.3(2))
4506 ("attribute % cannot appear in the condition "
4507 & "of a contract case", P
);
4509 end Check_Use_In_Contract_Cases
;
4511 ----------------------------
4512 -- Check_Use_In_Test_Case --
4513 ----------------------------
4515 procedure Check_Use_In_Test_Case
(Prag
: Node_Id
) is
4516 Ensures
: constant Node_Id
:= Get_Ensures_From_CTC_Pragma
(Prag
);
4520 -- Climb the parent chain to reach the top of the Ensures part of
4521 -- pragma Test_Case.
4524 while Expr
/= Prag
loop
4525 if Expr
= Ensures
then
4529 Expr
:= Parent
(Expr
);
4532 -- If we get there, then attribute 'Old appears in the requires
4533 -- expression of pragma Test_Case which is not a postcondition-
4537 ("attribute % cannot appear in the requires expression of a "
4539 end Check_Use_In_Test_Case
;
4544 -- The enclosing scope, excluding loops for quantified expressions.
4545 -- During analysis, it is the postcondition subprogram. During
4546 -- pre-analysis, it is the scope of the subprogram declaration.
4549 -- During pre-analysis, Prag is the enclosing pragma node if any
4551 -- Start of processing for Old
4556 -- Find enclosing scopes, excluding loops
4558 CS
:= Current_Scope
;
4559 while Ekind
(CS
) = E_Loop
loop
4563 -- A Contract_Cases, Postcondition or Test_Case pragma is in the
4564 -- process of being preanalyzed. Perform the semantic checks now
4565 -- before the pragma is relocated and/or expanded.
4567 if In_Spec_Expression
then
4569 while Present
(Prag
)
4570 and then not Nkind_In
(Prag
, N_Aspect_Specification
,
4571 N_Function_Specification
,
4573 N_Procedure_Specification
,
4576 Prag
:= Parent
(Prag
);
4579 -- In ASIS mode, the aspect itself is analyzed, in addition to the
4580 -- corresponding pragma. Do not issue errors when analyzing the
4583 if Nkind
(Prag
) = N_Aspect_Specification
then
4586 -- In all other cases the related context must be a pragma
4588 elsif Nkind
(Prag
) /= N_Pragma
then
4589 Error_Attr
("% attribute can only appear in postcondition", P
);
4591 -- Verify the placement of the attribute with respect to the
4595 case Get_Pragma_Id
(Prag
) is
4596 when Pragma_Contract_Cases
=>
4597 Check_Use_In_Contract_Cases
(Prag
);
4599 when Pragma_Postcondition | Pragma_Refined_Post
=>
4602 when Pragma_Test_Case
=>
4603 Check_Use_In_Test_Case
(Prag
);
4607 ("% attribute can only appear in postcondition", P
);
4611 -- Check the legality of attribute 'Old when it appears inside pragma
4612 -- Refined_Post. These specialized checks are required only when code
4613 -- generation is disabled. In the general case pragma Refined_Post is
4614 -- transformed into pragma Check by Process_PPCs which in turn is
4615 -- relocated to procedure _Postconditions. From then on the legality
4616 -- of 'Old is determined as usual.
4618 elsif not Expander_Active
and then In_Refined_Post
then
4619 Preanalyze_And_Resolve
(P
);
4620 Check_References_In_Prefix
(CS
);
4621 P_Type
:= Etype
(P
);
4622 Set_Etype
(N
, P_Type
);
4624 if Is_Limited_Type
(P_Type
) then
4625 Error_Attr
("attribute % cannot apply to limited objects", P
);
4628 if Is_Entity_Name
(P
)
4629 and then Is_Constant_Object
(Entity
(P
))
4632 ("??attribute Old applied to constant has no effect", P
);
4637 -- Body case, where we must be inside a generated _Postconditions
4638 -- procedure, or else the attribute use is definitely misplaced. The
4639 -- postcondition itself may have generated transient scopes, and is
4640 -- not necessarily the current one.
4643 while Present
(CS
) and then CS
/= Standard_Standard
loop
4644 if Chars
(CS
) = Name_uPostconditions
then
4651 if Chars
(CS
) /= Name_uPostconditions
then
4652 Error_Attr
("% attribute can only appear in postcondition", P
);
4656 -- If the attribute reference is generated for a Requires clause,
4657 -- then no expressions follow. Otherwise it is a primary, in which
4658 -- case, if expressions follow, the attribute reference must be an
4659 -- indexable object, so rewrite the node accordingly.
4661 if Present
(E1
) then
4663 Make_Indexed_Component
(Loc
,
4665 Make_Attribute_Reference
(Loc
,
4666 Prefix
=> Relocate_Node
(Prefix
(N
)),
4667 Attribute_Name
=> Name_Old
),
4668 Expressions
=> Expressions
(N
)));
4676 -- Prefix has not been analyzed yet, and its full analysis will take
4677 -- place during expansion (see below).
4679 Preanalyze_And_Resolve
(P
);
4680 Check_References_In_Prefix
(CS
);
4681 P_Type
:= Etype
(P
);
4682 Set_Etype
(N
, P_Type
);
4684 if Is_Limited_Type
(P_Type
) then
4685 Error_Attr
("attribute % cannot apply to limited objects", P
);
4688 if Is_Entity_Name
(P
)
4689 and then Is_Constant_Object
(Entity
(P
))
4692 ("??attribute Old applied to constant has no effect", P
);
4695 -- Check that the prefix of 'Old is an entity, when it appears in
4696 -- a postcondition and may be potentially unevaluated (6.1.1 (27/3)).
4699 and then Get_Pragma_Id
(Prag
) = Pragma_Postcondition
4700 and then Is_Potentially_Unevaluated
(N
)
4701 and then not Is_Entity_Name
(P
)
4704 ("prefix of attribute % that is potentially unevaluated must "
4705 & "denote an entity");
4708 -- The attribute appears within a pre/postcondition, but refers to
4709 -- an entity in the enclosing subprogram. If it is a component of
4710 -- a formal its expansion might generate actual subtypes that may
4711 -- be referenced in an inner context, and which must be elaborated
4712 -- within the subprogram itself. If the prefix includes a function
4713 -- call it may involve finalization actions that should only be
4714 -- inserted when the attribute has been rewritten as a declarations.
4715 -- As a result, if the prefix is not a simple name we create
4716 -- a declaration for it now, and insert it at the start of the
4717 -- enclosing subprogram. This is properly an expansion activity
4718 -- but it has to be performed now to prevent out-of-order issues.
4720 -- This expansion is both harmful and not needed in SPARK mode, since
4721 -- the formal verification backend relies on the types of nodes
4722 -- (hence is not robust w.r.t. a change to base type here), and does
4723 -- not suffer from the out-of-order issue described above. Thus, this
4724 -- expansion is skipped in SPARK mode.
4726 if not Is_Entity_Name
(P
) and then not GNATprove_Mode
then
4727 P_Type
:= Base_Type
(P_Type
);
4728 Set_Etype
(N
, P_Type
);
4729 Set_Etype
(P
, P_Type
);
4730 Analyze_Dimension
(N
);
4735 ----------------------
4736 -- Overlaps_Storage --
4737 ----------------------
4739 when Attribute_Overlaps_Storage
=>
4742 -- Both arguments must be objects of any type
4744 Analyze_And_Resolve
(P
);
4745 Analyze_And_Resolve
(E1
);
4746 Check_Object_Reference
(P
);
4747 Check_Object_Reference
(E1
);
4748 Set_Etype
(N
, Standard_Boolean
);
4754 when Attribute_Output
=>
4756 Check_Stream_Attribute
(TSS_Stream_Output
);
4757 Set_Etype
(N
, Standard_Void_Type
);
4758 Resolve
(N
, Standard_Void_Type
);
4764 when Attribute_Partition_ID
=> Partition_Id
:
4768 if P_Type
/= Any_Type
then
4769 if not Is_Library_Level_Entity
(Entity
(P
)) then
4771 ("prefix of % attribute must be library-level entity");
4773 -- The defining entity of prefix should not be declared inside a
4774 -- Pure unit. RM E.1(8). Is_Pure was set during declaration.
4776 elsif Is_Entity_Name
(P
)
4777 and then Is_Pure
(Entity
(P
))
4779 Error_Attr_P
("prefix of% attribute must not be declared pure");
4783 Set_Etype
(N
, Universal_Integer
);
4786 -------------------------
4787 -- Passed_By_Reference --
4788 -------------------------
4790 when Attribute_Passed_By_Reference
=>
4793 Set_Etype
(N
, Standard_Boolean
);
4799 when Attribute_Pool_Address
=>
4801 Set_Etype
(N
, RTE
(RE_Address
));
4807 when Attribute_Pos
=>
4808 Check_Discrete_Type
;
4811 if Is_Boolean_Type
(P_Type
) then
4812 Error_Msg_Name_1
:= Aname
;
4813 Error_Msg_Name_2
:= Chars
(P_Type
);
4814 Check_SPARK_Restriction
4815 ("attribute% is not allowed for type%", P
);
4818 Resolve
(E1
, P_Base_Type
);
4819 Set_Etype
(N
, Universal_Integer
);
4825 when Attribute_Position
=>
4827 Set_Etype
(N
, Universal_Integer
);
4833 when Attribute_Pred
=>
4837 if Is_Real_Type
(P_Type
) or else Is_Boolean_Type
(P_Type
) then
4838 Error_Msg_Name_1
:= Aname
;
4839 Error_Msg_Name_2
:= Chars
(P_Type
);
4840 Check_SPARK_Restriction
("attribute% is not allowed for type%", P
);
4843 Resolve
(E1
, P_Base_Type
);
4844 Set_Etype
(N
, P_Base_Type
);
4846 -- For real types, enable range check in Check_Overflow_Mode only
4848 if Is_Real_Type
(P_Type
) then
4849 if Check_Float_Overflow
4850 and then not Range_Checks_Suppressed
(P_Base_Type
)
4852 Enable_Range_Check
(E1
);
4855 -- If not modular type, test for overflow check required
4858 if not Is_Modular_Integer_Type
(P_Type
)
4859 and then not Range_Checks_Suppressed
(P_Base_Type
)
4861 Enable_Range_Check
(E1
);
4869 -- Ada 2005 (AI-327): Dynamic ceiling priorities
4871 when Attribute_Priority
=>
4872 if Ada_Version
< Ada_2005
then
4873 Error_Attr
("% attribute is allowed only in Ada 2005 mode", P
);
4878 -- The prefix must be a protected object (AARM D.5.2 (2/2))
4882 if Is_Protected_Type
(Etype
(P
))
4883 or else (Is_Access_Type
(Etype
(P
))
4884 and then Is_Protected_Type
(Designated_Type
(Etype
(P
))))
4886 Resolve
(P
, Etype
(P
));
4888 Error_Attr_P
("prefix of % attribute must be a protected object");
4891 Set_Etype
(N
, Standard_Integer
);
4893 -- Must be called from within a protected procedure or entry of the
4894 -- protected object.
4901 while S
/= Etype
(P
)
4902 and then S
/= Standard_Standard
4907 if S
= Standard_Standard
then
4908 Error_Attr
("the attribute % is only allowed inside protected "
4913 Validate_Non_Static_Attribute_Function_Call
;
4919 when Attribute_Range
=>
4920 Check_Array_Or_Scalar_Type
;
4921 Bad_Attribute_For_Predicate
;
4923 if Ada_Version
= Ada_83
4924 and then Is_Scalar_Type
(P_Type
)
4925 and then Comes_From_Source
(N
)
4928 ("(Ada 83) % attribute not allowed for scalar type", P
);
4935 when Attribute_Result
=> Result
: declare
4937 -- The enclosing scope, excluding loops for quantified expressions
4940 -- During analysis, CS is the postcondition subprogram and PS the
4941 -- source subprogram to which the postcondition applies. During
4942 -- pre-analysis, CS is the scope of the subprogram declaration.
4945 -- During pre-analysis, Prag is the enclosing pragma node if any
4948 -- Find the proper enclosing scope
4950 CS
:= Current_Scope
;
4951 while Present
(CS
) loop
4953 -- Skip generated loops
4955 if Ekind
(CS
) = E_Loop
then
4958 -- Skip the special _Parent scope generated to capture references
4959 -- to formals during the process of subprogram inlining.
4961 elsif Ekind
(CS
) = E_Function
4962 and then Chars
(CS
) = Name_uParent
4972 -- If the enclosing subprogram is always inlined, the enclosing
4973 -- postcondition will not be propagated to the expanded call.
4975 if not In_Spec_Expression
4976 and then Has_Pragma_Inline_Always
(PS
)
4977 and then Warn_On_Redundant_Constructs
4980 ("postconditions on inlined functions not enforced?r?", N
);
4983 -- If we are in the scope of a function and in Spec_Expression mode,
4984 -- this is likely the prescan of the postcondition (or contract case,
4985 -- or test case) pragma, and we just set the proper type. If there is
4986 -- an error it will be caught when the real Analyze call is done.
4988 if Ekind
(CS
) = E_Function
4989 and then In_Spec_Expression
4993 if Chars
(CS
) /= Chars
(P
) then
4994 Error_Msg_Name_1
:= Name_Result
;
4997 ("incorrect prefix for % attribute, expected &", P
, CS
);
5001 -- Check in postcondition, Test_Case or Contract_Cases of function
5004 while Present
(Prag
)
5005 and then not Nkind_In
(Prag
, N_Pragma
,
5006 N_Function_Specification
,
5007 N_Aspect_Specification
,
5010 Prag
:= Parent
(Prag
);
5013 -- In ASIS mode, the aspect itself is analyzed, in addition to the
5014 -- corresponding pragma. Do not issue errors when analyzing the
5017 if Nkind
(Prag
) = N_Aspect_Specification
then
5020 -- Must have a pragma
5022 elsif Nkind
(Prag
) /= N_Pragma
then
5024 ("% attribute can only appear in postcondition of function",
5027 -- Processing depends on which pragma we have
5030 case Get_Pragma_Id
(Prag
) is
5032 when Pragma_Test_Case
=>
5034 Arg_Ens
: constant Node_Id
:=
5035 Get_Ensures_From_CTC_Pragma
(Prag
);
5040 while Arg
/= Prag
and then Arg
/= Arg_Ens
loop
5041 Arg
:= Parent
(Arg
);
5044 if Arg
/= Arg_Ens
then
5046 ("% attribute misplaced inside test case", P
);
5050 when Pragma_Contract_Cases
=>
5052 Aggr
: constant Node_Id
:=
5054 (Pragma_Argument_Associations
(Prag
)));
5060 and then Parent
(Parent
(Arg
)) /= Aggr
5062 Arg
:= Parent
(Arg
);
5065 -- At this point, Parent (Arg) should be a component
5066 -- association. Attribute Result is only allowed in
5067 -- the expression part of this association.
5069 if Nkind
(Parent
(Arg
)) /= N_Component_Association
5070 or else Arg
/= Expression
(Parent
(Arg
))
5073 ("% attribute misplaced inside contract cases",
5078 when Pragma_Postcondition | Pragma_Refined_Post
=>
5083 ("% attribute can only appear in postcondition "
5084 & "of function", P
);
5088 -- The attribute reference is a primary. If expressions follow,
5089 -- the attribute reference is really an indexable object, so
5090 -- rewrite and analyze as an indexed component.
5092 if Present
(E1
) then
5094 Make_Indexed_Component
(Loc
,
5096 Make_Attribute_Reference
(Loc
,
5097 Prefix
=> Relocate_Node
(Prefix
(N
)),
5098 Attribute_Name
=> Name_Result
),
5099 Expressions
=> Expressions
(N
)));
5104 Set_Etype
(N
, Etype
(CS
));
5106 -- If several functions with that name are visible, the intended
5107 -- one is the current scope.
5109 if Is_Overloaded
(P
) then
5111 Set_Is_Overloaded
(P
, False);
5114 -- Check the legality of attribute 'Result when it appears inside
5115 -- pragma Refined_Post. These specialized checks are required only
5116 -- when code generation is disabled. In the general case pragma
5117 -- Refined_Post is transformed into pragma Check by Process_PPCs
5118 -- which in turn is relocated to procedure _Postconditions. From
5119 -- then on the legality of 'Result is determined as usual.
5121 elsif not Expander_Active
and then In_Refined_Post
then
5122 PS
:= Current_Scope
;
5124 -- The prefix denotes the proper related function
5126 if Is_Entity_Name
(P
)
5127 and then Ekind
(Entity
(P
)) = E_Function
5128 and then Entity
(P
) = PS
5133 Error_Msg_Name_2
:= Chars
(PS
);
5134 Error_Attr
("incorrect prefix for % attribute, expected %", P
);
5137 Set_Etype
(N
, Etype
(PS
));
5139 -- Body case, where we must be inside a generated _Postconditions
5140 -- procedure, and the prefix must be on the scope stack, or else the
5141 -- attribute use is definitely misplaced. The postcondition itself
5142 -- may have generated transient scopes, and is not necessarily the
5146 while Present
(CS
) and then CS
/= Standard_Standard
loop
5147 if Chars
(CS
) = Name_uPostconditions
then
5156 if Chars
(CS
) = Name_uPostconditions
5157 and then Ekind
(PS
) = E_Function
5161 if Nkind_In
(P
, N_Identifier
, N_Operator_Symbol
)
5162 and then Chars
(P
) = Chars
(PS
)
5166 -- Within an instance, the prefix designates the local renaming
5167 -- of the original generic.
5169 elsif Is_Entity_Name
(P
)
5170 and then Ekind
(Entity
(P
)) = E_Function
5171 and then Present
(Alias
(Entity
(P
)))
5172 and then Chars
(Alias
(Entity
(P
))) = Chars
(PS
)
5177 Error_Msg_Name_2
:= Chars
(PS
);
5179 ("incorrect prefix for % attribute, expected %", P
);
5182 Rewrite
(N
, Make_Identifier
(Sloc
(N
), Name_uResult
));
5183 Analyze_And_Resolve
(N
, Etype
(PS
));
5187 ("% attribute can only appear in postcondition of function",
5197 when Attribute_Range_Length
=>
5199 Check_Discrete_Type
;
5200 Set_Etype
(N
, Universal_Integer
);
5206 when Attribute_Read
=>
5208 Check_Stream_Attribute
(TSS_Stream_Read
);
5209 Set_Etype
(N
, Standard_Void_Type
);
5210 Resolve
(N
, Standard_Void_Type
);
5211 Note_Possible_Modification
(E2
, Sure
=> True);
5217 when Attribute_Ref
=>
5221 if Nkind
(P
) /= N_Expanded_Name
5222 or else not Is_RTE
(P_Type
, RE_Address
)
5224 Error_Attr_P
("prefix of % attribute must be System.Address");
5227 Analyze_And_Resolve
(E1
, Any_Integer
);
5228 Set_Etype
(N
, RTE
(RE_Address
));
5234 when Attribute_Remainder
=>
5235 Check_Floating_Point_Type_2
;
5236 Set_Etype
(N
, P_Base_Type
);
5237 Resolve
(E1
, P_Base_Type
);
5238 Resolve
(E2
, P_Base_Type
);
5240 ---------------------
5241 -- Restriction_Set --
5242 ---------------------
5244 when Attribute_Restriction_Set
=> Restriction_Set
: declare
5247 Unam
: Unit_Name_Type
;
5252 Check_System_Prefix
;
5254 -- No_Dependence case
5256 if Nkind
(E1
) = N_Parameter_Association
then
5257 pragma Assert
(Chars
(Selector_Name
(E1
)) = Name_No_Dependence
);
5258 U
:= Explicit_Actual_Parameter
(E1
);
5260 if not OK_No_Dependence_Unit_Name
(U
) then
5261 Set_Boolean_Result
(N
, False);
5265 -- See if there is an entry already in the table. That's the
5266 -- case in which we can return True.
5268 for J
in No_Dependences
.First
.. No_Dependences
.Last
loop
5269 if Designate_Same_Unit
(U
, No_Dependences
.Table
(J
).Unit
)
5270 and then No_Dependences
.Table
(J
).Warn
= False
5272 Set_Boolean_Result
(N
, True);
5277 -- If not in the No_Dependence table, result is False
5279 Set_Boolean_Result
(N
, False);
5281 -- In this case, we must ensure that the binder will reject any
5282 -- other unit in the partition that sets No_Dependence for this
5283 -- unit. We do that by making an entry in the special table kept
5284 -- for this purpose (if the entry is not there already).
5286 Unam
:= Get_Spec_Name
(Get_Unit_Name
(U
));
5288 for J
in Restriction_Set_Dependences
.First
..
5289 Restriction_Set_Dependences
.Last
5291 if Restriction_Set_Dependences
.Table
(J
) = Unam
then
5296 Restriction_Set_Dependences
.Append
(Unam
);
5298 -- Normal restriction case
5301 if Nkind
(E1
) /= N_Identifier
then
5302 Set_Boolean_Result
(N
, False);
5303 Error_Attr
("attribute % requires restriction identifier", E1
);
5306 R
:= Get_Restriction_Id
(Process_Restriction_Synonyms
(E1
));
5308 if R
= Not_A_Restriction_Id
then
5309 Set_Boolean_Result
(N
, False);
5310 Error_Msg_Node_1
:= E1
;
5311 Error_Attr
("invalid restriction identifier &", E1
);
5313 elsif R
not in Partition_Boolean_Restrictions
then
5314 Set_Boolean_Result
(N
, False);
5315 Error_Msg_Node_1
:= E1
;
5317 ("& is not a boolean partition-wide restriction", E1
);
5320 if Restriction_Active
(R
) then
5321 Set_Boolean_Result
(N
, True);
5323 Check_Restriction
(R
, N
);
5324 Set_Boolean_Result
(N
, False);
5328 end Restriction_Set
;
5334 when Attribute_Round
=>
5336 Check_Decimal_Fixed_Point_Type
;
5337 Set_Etype
(N
, P_Base_Type
);
5339 -- Because the context is universal_real (3.5.10(12)) it is a
5340 -- legal context for a universal fixed expression. This is the
5341 -- only attribute whose functional description involves U_R.
5343 if Etype
(E1
) = Universal_Fixed
then
5345 Conv
: constant Node_Id
:= Make_Type_Conversion
(Loc
,
5346 Subtype_Mark
=> New_Occurrence_Of
(Universal_Real
, Loc
),
5347 Expression
=> Relocate_Node
(E1
));
5355 Resolve
(E1
, Any_Real
);
5361 when Attribute_Rounding
=>
5362 Check_Floating_Point_Type_1
;
5363 Set_Etype
(N
, P_Base_Type
);
5364 Resolve
(E1
, P_Base_Type
);
5370 when Attribute_Safe_Emax
=>
5371 Check_Floating_Point_Type_0
;
5372 Set_Etype
(N
, Universal_Integer
);
5378 when Attribute_Safe_First
=>
5379 Check_Floating_Point_Type_0
;
5380 Set_Etype
(N
, Universal_Real
);
5386 when Attribute_Safe_Large
=>
5389 Set_Etype
(N
, Universal_Real
);
5395 when Attribute_Safe_Last
=>
5396 Check_Floating_Point_Type_0
;
5397 Set_Etype
(N
, Universal_Real
);
5403 when Attribute_Safe_Small
=>
5406 Set_Etype
(N
, Universal_Real
);
5412 when Attribute_Same_Storage
=>
5413 Check_Ada_2012_Attribute
;
5416 -- The arguments must be objects of any type
5418 Analyze_And_Resolve
(P
);
5419 Analyze_And_Resolve
(E1
);
5420 Check_Object_Reference
(P
);
5421 Check_Object_Reference
(E1
);
5422 Set_Etype
(N
, Standard_Boolean
);
5424 --------------------------
5425 -- Scalar_Storage_Order --
5426 --------------------------
5428 when Attribute_Scalar_Storage_Order
=> Scalar_Storage_Order
:
5430 Ent
: Entity_Id
:= Empty
;
5436 if not (Is_Record_Type
(P_Type
) or else Is_Array_Type
(P_Type
)) then
5438 -- In GNAT mode, the attribute applies to generic types as well
5439 -- as composite types, and for non-composite types always returns
5440 -- the default bit order for the target.
5442 if not (GNAT_Mode
and then Is_Generic_Type
(P_Type
))
5443 and then not In_Instance
5446 ("prefix of % attribute must be record or array type");
5448 elsif not Is_Generic_Type
(P_Type
) then
5449 if Bytes_Big_Endian
then
5450 Ent
:= RTE
(RE_High_Order_First
);
5452 Ent
:= RTE
(RE_Low_Order_First
);
5456 elsif Bytes_Big_Endian
xor Reverse_Storage_Order
(P_Type
) then
5457 Ent
:= RTE
(RE_High_Order_First
);
5460 Ent
:= RTE
(RE_Low_Order_First
);
5463 if Present
(Ent
) then
5464 Rewrite
(N
, New_Occurrence_Of
(Ent
, Loc
));
5467 Set_Etype
(N
, RTE
(RE_Bit_Order
));
5470 -- Reset incorrect indication of staticness
5472 Set_Is_Static_Expression
(N
, False);
5473 end Scalar_Storage_Order
;
5479 when Attribute_Scale
=>
5481 Check_Decimal_Fixed_Point_Type
;
5482 Set_Etype
(N
, Universal_Integer
);
5488 when Attribute_Scaling
=>
5489 Check_Floating_Point_Type_2
;
5490 Set_Etype
(N
, P_Base_Type
);
5491 Resolve
(E1
, P_Base_Type
);
5497 when Attribute_Signed_Zeros
=>
5498 Check_Floating_Point_Type_0
;
5499 Set_Etype
(N
, Standard_Boolean
);
5505 when Attribute_Size | Attribute_VADS_Size
=> Size
:
5509 -- If prefix is parameterless function call, rewrite and resolve
5512 if Is_Entity_Name
(P
)
5513 and then Ekind
(Entity
(P
)) = E_Function
5517 -- Similar processing for a protected function call
5519 elsif Nkind
(P
) = N_Selected_Component
5520 and then Ekind
(Entity
(Selector_Name
(P
))) = E_Function
5525 if Is_Object_Reference
(P
) then
5526 Check_Object_Reference
(P
);
5528 elsif Is_Entity_Name
(P
)
5529 and then (Is_Type
(Entity
(P
))
5530 or else Ekind
(Entity
(P
)) = E_Enumeration_Literal
)
5534 elsif Nkind
(P
) = N_Type_Conversion
5535 and then not Comes_From_Source
(P
)
5539 -- Some other compilers allow dubious use of X'???'Size
5541 elsif Relaxed_RM_Semantics
5542 and then Nkind
(P
) = N_Attribute_Reference
5547 Error_Attr_P
("invalid prefix for % attribute");
5550 Check_Not_Incomplete_Type
;
5552 Set_Etype
(N
, Universal_Integer
);
5559 when Attribute_Small
=>
5562 Set_Etype
(N
, Universal_Real
);
5568 when Attribute_Storage_Pool |
5569 Attribute_Simple_Storage_Pool
=> Storage_Pool
:
5573 if Is_Access_Type
(P_Type
) then
5574 if Ekind
(P_Type
) = E_Access_Subprogram_Type
then
5576 ("cannot use % attribute for access-to-subprogram type");
5579 -- Set appropriate entity
5581 if Present
(Associated_Storage_Pool
(Root_Type
(P_Type
))) then
5582 Set_Entity
(N
, Associated_Storage_Pool
(Root_Type
(P_Type
)));
5584 Set_Entity
(N
, RTE
(RE_Global_Pool_Object
));
5587 if Attr_Id
= Attribute_Storage_Pool
then
5588 if Present
(Get_Rep_Pragma
(Etype
(Entity
(N
)),
5589 Name_Simple_Storage_Pool_Type
))
5591 Error_Msg_Name_1
:= Aname
;
5592 Error_Msg_Warn
:= SPARK_Mode
/= On
;
5593 Error_Msg_N
("cannot use % attribute for type with simple "
5594 & "storage pool<<", N
);
5595 Error_Msg_N
("\Program_Error [<<", N
);
5598 (N
, Make_Raise_Program_Error
5599 (Sloc
(N
), Reason
=> PE_Explicit_Raise
));
5602 Set_Etype
(N
, Class_Wide_Type
(RTE
(RE_Root_Storage_Pool
)));
5604 -- In the Simple_Storage_Pool case, verify that the pool entity is
5605 -- actually of a simple storage pool type, and set the attribute's
5606 -- type to the pool object's type.
5609 if not Present
(Get_Rep_Pragma
(Etype
(Entity
(N
)),
5610 Name_Simple_Storage_Pool_Type
))
5613 ("cannot use % attribute for type without simple " &
5617 Set_Etype
(N
, Etype
(Entity
(N
)));
5620 -- Validate_Remote_Access_To_Class_Wide_Type for attribute
5621 -- Storage_Pool since this attribute is not defined for such
5622 -- types (RM E.2.3(22)).
5624 Validate_Remote_Access_To_Class_Wide_Type
(N
);
5627 Error_Attr_P
("prefix of % attribute must be access type");
5635 when Attribute_Storage_Size
=> Storage_Size
:
5639 if Is_Task_Type
(P_Type
) then
5640 Set_Etype
(N
, Universal_Integer
);
5642 -- Use with tasks is an obsolescent feature
5644 Check_Restriction
(No_Obsolescent_Features
, P
);
5646 elsif Is_Access_Type
(P_Type
) then
5647 if Ekind
(P_Type
) = E_Access_Subprogram_Type
then
5649 ("cannot use % attribute for access-to-subprogram type");
5652 if Is_Entity_Name
(P
)
5653 and then Is_Type
(Entity
(P
))
5656 Set_Etype
(N
, Universal_Integer
);
5658 -- Validate_Remote_Access_To_Class_Wide_Type for attribute
5659 -- Storage_Size since this attribute is not defined for
5660 -- such types (RM E.2.3(22)).
5662 Validate_Remote_Access_To_Class_Wide_Type
(N
);
5664 -- The prefix is allowed to be an implicit dereference of an
5665 -- access value designating a task.
5669 Set_Etype
(N
, Universal_Integer
);
5673 Error_Attr_P
("prefix of % attribute must be access or task type");
5681 when Attribute_Storage_Unit
=>
5682 Standard_Attribute
(Ttypes
.System_Storage_Unit
);
5688 when Attribute_Stream_Size
=>
5692 if Is_Entity_Name
(P
)
5693 and then Is_Elementary_Type
(Entity
(P
))
5695 Set_Etype
(N
, Universal_Integer
);
5697 Error_Attr_P
("invalid prefix for % attribute");
5704 when Attribute_Stub_Type
=>
5708 if Is_Remote_Access_To_Class_Wide_Type
(Base_Type
(P_Type
)) then
5710 -- For a real RACW [sub]type, use corresponding stub type
5712 if not Is_Generic_Type
(P_Type
) then
5715 (Corresponding_Stub_Type
(Base_Type
(P_Type
)), Loc
));
5717 -- For a generic type (that has been marked as an RACW using the
5718 -- Remote_Access_Type aspect or pragma), use a generic RACW stub
5719 -- type. Note that if the actual is not a remote access type, the
5720 -- instantiation will fail.
5723 -- Note: we go to the underlying type here because the view
5724 -- returned by RTE (RE_RACW_Stub_Type) might be incomplete.
5728 (Underlying_Type
(RTE
(RE_RACW_Stub_Type
)), Loc
));
5733 ("prefix of% attribute must be remote access to classwide");
5740 when Attribute_Succ
=>
5744 if Is_Real_Type
(P_Type
) or else Is_Boolean_Type
(P_Type
) then
5745 Error_Msg_Name_1
:= Aname
;
5746 Error_Msg_Name_2
:= Chars
(P_Type
);
5747 Check_SPARK_Restriction
("attribute% is not allowed for type%", P
);
5750 Resolve
(E1
, P_Base_Type
);
5751 Set_Etype
(N
, P_Base_Type
);
5753 -- For real types, enable range check in Check_Overflow_Mode only
5755 if Is_Real_Type
(P_Type
) then
5756 if Check_Float_Overflow
5757 and then not Range_Checks_Suppressed
(P_Base_Type
)
5759 Enable_Range_Check
(E1
);
5762 -- If not modular type, test for overflow check required
5765 if not Is_Modular_Integer_Type
(P_Type
)
5766 and then not Range_Checks_Suppressed
(P_Base_Type
)
5768 Enable_Range_Check
(E1
);
5772 --------------------------------
5773 -- System_Allocator_Alignment --
5774 --------------------------------
5776 when Attribute_System_Allocator_Alignment
=>
5777 Standard_Attribute
(Ttypes
.System_Allocator_Alignment
);
5783 when Attribute_Tag
=> Tag
:
5788 if not Is_Tagged_Type
(P_Type
) then
5789 Error_Attr_P
("prefix of % attribute must be tagged");
5791 -- Next test does not apply to generated code why not, and what does
5792 -- the illegal reference mean???
5794 elsif Is_Object_Reference
(P
)
5795 and then not Is_Class_Wide_Type
(P_Type
)
5796 and then Comes_From_Source
(N
)
5799 ("% attribute can only be applied to objects " &
5800 "of class - wide type");
5803 -- The prefix cannot be an incomplete type. However, references to
5804 -- 'Tag can be generated when expanding interface conversions, and
5807 if Comes_From_Source
(N
) then
5808 Check_Not_Incomplete_Type
;
5811 -- Set appropriate type
5813 Set_Etype
(N
, RTE
(RE_Tag
));
5820 when Attribute_Target_Name
=> Target_Name
: declare
5821 TN
: constant String := Sdefault
.Target_Name
.all;
5825 Check_Standard_Prefix
;
5829 if TN
(TL
) = '/' or else TN
(TL
) = '\' then
5834 Make_String_Literal
(Loc
,
5835 Strval
=> TN
(TN
'First .. TL
)));
5836 Analyze_And_Resolve
(N
, Standard_String
);
5843 when Attribute_Terminated
=>
5845 Set_Etype
(N
, Standard_Boolean
);
5852 when Attribute_To_Address
=> To_Address
: declare
5858 Check_System_Prefix
;
5860 Generate_Reference
(RTE
(RE_Address
), P
);
5861 Analyze_And_Resolve
(E1
, Any_Integer
);
5862 Set_Etype
(N
, RTE
(RE_Address
));
5864 -- Static expression case, check range and set appropriate type
5866 if Is_OK_Static_Expression
(E1
) then
5867 Val
:= Expr_Value
(E1
);
5869 if Val
< -(2 ** UI_From_Int
(Standard
'Address_Size - 1))
5871 Val
> 2 ** UI_From_Int
(Standard
'Address_Size) - 1
5873 Error_Attr
("address value out of range for % attribute", E1
);
5876 -- In most cases the expression is a numeric literal or some other
5877 -- address expression, but if it is a declared constant it may be
5878 -- of a compatible type that must be left on the node.
5880 if Is_Entity_Name
(E1
) then
5883 -- Set type to universal integer if negative
5886 Set_Etype
(E1
, Universal_Integer
);
5888 -- Otherwise set type to Unsigned_64 to accomodate max values
5891 Set_Etype
(E1
, Standard_Unsigned_64
);
5900 when Attribute_To_Any
=>
5902 Check_PolyORB_Attribute
;
5903 Set_Etype
(N
, RTE
(RE_Any
));
5909 when Attribute_Truncation
=>
5910 Check_Floating_Point_Type_1
;
5911 Resolve
(E1
, P_Base_Type
);
5912 Set_Etype
(N
, P_Base_Type
);
5918 when Attribute_Type_Class
=>
5921 Check_Not_Incomplete_Type
;
5922 Set_Etype
(N
, RTE
(RE_Type_Class
));
5928 when Attribute_TypeCode
=>
5930 Check_PolyORB_Attribute
;
5931 Set_Etype
(N
, RTE
(RE_TypeCode
));
5937 when Attribute_Type_Key
=>
5941 -- This processing belongs in Eval_Attribute ???
5944 function Type_Key
return String_Id
;
5945 -- A very preliminary implementation. For now, a signature
5946 -- consists of only the type name. This is clearly incomplete
5947 -- (e.g., adding a new field to a record type should change the
5948 -- type's Type_Key attribute).
5954 function Type_Key
return String_Id
is
5955 Full_Name
: constant String_Id
:=
5956 Fully_Qualified_Name_String
(Entity
(P
));
5959 -- Copy all characters in Full_Name but the trailing NUL
5962 for J
in 1 .. String_Length
(Full_Name
) - 1 loop
5963 Store_String_Char
(Get_String_Char
(Full_Name
, Int
(J
)));
5966 Store_String_Chars
("'Type_Key");
5971 Rewrite
(N
, Make_String_Literal
(Loc
, Type_Key
));
5974 Analyze_And_Resolve
(N
, Standard_String
);
5980 when Attribute_UET_Address
=>
5982 Check_Unit_Name
(P
);
5983 Set_Etype
(N
, RTE
(RE_Address
));
5985 -----------------------
5986 -- Unbiased_Rounding --
5987 -----------------------
5989 when Attribute_Unbiased_Rounding
=>
5990 Check_Floating_Point_Type_1
;
5991 Set_Etype
(N
, P_Base_Type
);
5992 Resolve
(E1
, P_Base_Type
);
5994 ----------------------
5995 -- Unchecked_Access --
5996 ----------------------
5998 when Attribute_Unchecked_Access
=>
5999 if Comes_From_Source
(N
) then
6000 Check_Restriction
(No_Unchecked_Access
, N
);
6003 Analyze_Access_Attribute
;
6005 -------------------------
6006 -- Unconstrained_Array --
6007 -------------------------
6009 when Attribute_Unconstrained_Array
=>
6012 Check_Not_Incomplete_Type
;
6013 Set_Etype
(N
, Standard_Boolean
);
6015 ------------------------------
6016 -- Universal_Literal_String --
6017 ------------------------------
6019 -- This is a GNAT specific attribute whose prefix must be a named
6020 -- number where the expression is either a single numeric literal,
6021 -- or a numeric literal immediately preceded by a minus sign. The
6022 -- result is equivalent to a string literal containing the text of
6023 -- the literal as it appeared in the source program with a possible
6024 -- leading minus sign.
6026 when Attribute_Universal_Literal_String
=> Universal_Literal_String
:
6030 if not Is_Entity_Name
(P
)
6031 or else Ekind
(Entity
(P
)) not in Named_Kind
6033 Error_Attr_P
("prefix for % attribute must be named number");
6040 Src
: Source_Buffer_Ptr
;
6043 Expr
:= Original_Node
(Expression
(Parent
(Entity
(P
))));
6045 if Nkind
(Expr
) = N_Op_Minus
then
6047 Expr
:= Original_Node
(Right_Opnd
(Expr
));
6052 if not Nkind_In
(Expr
, N_Integer_Literal
, N_Real_Literal
) then
6054 ("named number for % attribute must be simple literal", N
);
6057 -- Build string literal corresponding to source literal text
6062 Store_String_Char
(Get_Char_Code
('-'));
6066 Src
:= Source_Text
(Get_Source_File_Index
(S
));
6068 while Src
(S
) /= ';' and then Src
(S
) /= ' ' loop
6069 Store_String_Char
(Get_Char_Code
(Src
(S
)));
6073 -- Now we rewrite the attribute with the string literal
6076 Make_String_Literal
(Loc
, End_String
));
6080 end Universal_Literal_String
;
6082 -------------------------
6083 -- Unrestricted_Access --
6084 -------------------------
6086 -- This is a GNAT specific attribute which is like Access except that
6087 -- all scope checks and checks for aliased views are omitted. It is
6088 -- documented as being equivalent to the use of the Address attribute
6089 -- followed by an unchecked conversion to the target access type.
6091 when Attribute_Unrestricted_Access
=>
6093 -- If from source, deal with relevant restrictions
6095 if Comes_From_Source
(N
) then
6096 Check_Restriction
(No_Unchecked_Access
, N
);
6098 if Nkind
(P
) in N_Has_Entity
6099 and then Present
(Entity
(P
))
6100 and then Is_Object
(Entity
(P
))
6102 Check_Restriction
(No_Implicit_Aliasing
, N
);
6106 if Is_Entity_Name
(P
) then
6107 Set_Address_Taken
(Entity
(P
));
6110 -- It might seem reasonable to call Address_Checks here to apply the
6111 -- same set of semantic checks that we enforce for 'Address (after
6112 -- all we document Unrestricted_Access as being equivalent to the
6113 -- use of Address followed by an Unchecked_Conversion). However, if
6114 -- we do enable these checks, we get multiple failures in both the
6115 -- compiler run-time and in our regression test suite, so we leave
6116 -- out these checks for now. To be investigated further some time???
6120 -- Now complete analysis using common access processing
6122 Analyze_Access_Attribute
;
6128 when Attribute_Update
=> Update
: declare
6129 Comps
: Elist_Id
:= No_Elist
;
6131 procedure Check_Component_Reference
6134 -- Comp is a record component (possibly a discriminant) and Typ is a
6135 -- record type. Determine whether Comp is a legal component of Typ.
6136 -- Emit an error if Comp mentions a discriminant or is not a unique
6137 -- component reference in the update aggregate.
6139 -------------------------------
6140 -- Check_Component_Reference --
6141 -------------------------------
6143 procedure Check_Component_Reference
6147 Comp_Name
: constant Name_Id
:= Chars
(Comp
);
6149 function Is_Duplicate_Component
return Boolean;
6150 -- Determine whether component Comp already appears in list Comps
6152 ----------------------------
6153 -- Is_Duplicate_Component --
6154 ----------------------------
6156 function Is_Duplicate_Component
return Boolean is
6157 Comp_Elmt
: Elmt_Id
;
6160 if Present
(Comps
) then
6161 Comp_Elmt
:= First_Elmt
(Comps
);
6162 while Present
(Comp_Elmt
) loop
6163 if Chars
(Node
(Comp_Elmt
)) = Comp_Name
then
6167 Next_Elmt
(Comp_Elmt
);
6172 end Is_Duplicate_Component
;
6176 Comp_Or_Discr
: Entity_Id
;
6178 -- Start of processing for Check_Component_Reference
6181 -- Find the discriminant or component whose name corresponds to
6182 -- Comp. A simple character comparison is sufficient because all
6183 -- visible names within a record type are unique.
6185 Comp_Or_Discr
:= First_Entity
(Typ
);
6186 while Present
(Comp_Or_Discr
) loop
6187 if Chars
(Comp_Or_Discr
) = Comp_Name
then
6189 -- Record component entity and type in the given aggregate
6190 -- choice, for subsequent resolution.
6192 Set_Entity
(Comp
, Comp_Or_Discr
);
6193 Set_Etype
(Comp
, Etype
(Comp_Or_Discr
));
6197 Comp_Or_Discr
:= Next_Entity
(Comp_Or_Discr
);
6200 -- Diagnose possible illegal references
6202 if Present
(Comp_Or_Discr
) then
6203 if Ekind
(Comp_Or_Discr
) = E_Discriminant
then
6205 ("attribute % may not modify record discriminants", Comp
);
6207 else pragma Assert
(Ekind
(Comp_Or_Discr
) = E_Component
);
6208 if Is_Duplicate_Component
then
6209 Error_Msg_NE
("component & already updated", Comp
, Comp
);
6211 -- Mark this component as processed
6215 Comps
:= New_Elmt_List
;
6218 Append_Elmt
(Comp
, Comps
);
6222 -- The update aggregate mentions an entity that does not belong to
6227 ("& is not a component of aggregate subtype", Comp
, Comp
);
6229 end Check_Component_Reference
;
6235 Comp_Type
: Entity_Id
;
6237 -- Start of processing for Update
6241 Check_Ada_2012_Attribute
;
6243 if not Is_Object_Reference
(P
) then
6244 Error_Attr_P
("prefix of attribute % must denote an object");
6246 elsif not Is_Array_Type
(P_Type
)
6247 and then not Is_Record_Type
(P_Type
)
6249 Error_Attr_P
("prefix of attribute % must be a record or array");
6251 elsif Is_Limited_View
(P_Type
) then
6252 Error_Attr
("prefix of attribute % cannot be limited", N
);
6254 elsif Nkind
(E1
) /= N_Aggregate
then
6255 Error_Attr
("attribute % requires component association list", N
);
6258 -- Inspect the update aggregate, looking at all the associations and
6259 -- choices. Perform the following checks:
6261 -- 1) Legality of "others" in all cases
6262 -- 2) Component legality for records
6264 -- The remaining checks are performed on the expanded attribute
6266 Assoc
:= First
(Component_Associations
(E1
));
6267 while Present
(Assoc
) loop
6268 Comp
:= First
(Choices
(Assoc
));
6269 Analyze
(Expression
(Assoc
));
6271 while Present
(Comp
) loop
6272 if Nkind
(Comp
) = N_Others_Choice
then
6274 ("others choice not allowed in attribute %", Comp
);
6276 elsif Is_Array_Type
(P_Type
) then
6279 Index_Type
: Entity_Id
;
6282 if Nkind
(First
(Choices
(Assoc
))) /= N_Aggregate
then
6284 -- Choices denote separate components of one-
6285 -- dimensional array.
6287 Index_Type
:= First_Index
(P_Type
);
6289 if Present
(Next_Index
(Index_Type
)) then
6291 ("too few subscripts in array reference", Comp
);
6294 Index
:= First
(Choices
(Assoc
));
6295 while Present
(Index
) loop
6296 if Nkind
(Index
) = N_Range
then
6298 (Low_Bound
(Index
), Etype
(Index_Type
));
6300 (High_Bound
(Index
), Etype
(Index_Type
));
6301 Set_Etype
(Index
, Etype
(Index_Type
));
6304 Analyze_And_Resolve
(Index
, Etype
(Index_Type
));
6310 -- Choice is a sequence of indexes for each dimension
6313 Index_Type
:= First_Index
(P_Type
);
6314 Index
:= First
(Expressions
(First
(Choices
(Assoc
))));
6315 while Present
(Index_Type
)
6316 and then Present
(Index
)
6318 Analyze_And_Resolve
(Index
, Etype
(Index_Type
));
6319 Next_Index
(Index_Type
);
6323 if Present
(Index
) or else Present
(Index_Type
) then
6325 ("dimension mismatch in index list", Assoc
);
6330 elsif Is_Record_Type
(P_Type
) then
6332 -- Make sure we have an identifier. Old SPARK allowed
6333 -- a component selection e.g. A.B in the corresponding
6334 -- context, but we do not yet permit this for 'Update.
6336 if Nkind
(Comp
) /= N_Identifier
then
6337 Error_Msg_N
("name should be identifier or OTHERS", Comp
);
6339 Check_Component_Reference
(Comp
, P_Type
);
6341 -- Verify that all choices in an association denote
6342 -- components of the same type.
6344 if No
(Etype
(Comp
)) then
6347 elsif No
(Comp_Type
) then
6348 Comp_Type
:= Base_Type
(Etype
(Comp
));
6350 elsif Comp_Type
/= Base_Type
(Etype
(Comp
)) then
6352 ("components in choice list must have same type",
6364 -- The type of attribute Update is that of the prefix
6366 Set_Etype
(N
, P_Type
);
6373 when Attribute_Val
=> Val
: declare
6376 Check_Discrete_Type
;
6378 if Is_Boolean_Type
(P_Type
) then
6379 Error_Msg_Name_1
:= Aname
;
6380 Error_Msg_Name_2
:= Chars
(P_Type
);
6381 Check_SPARK_Restriction
6382 ("attribute% is not allowed for type%", P
);
6385 Resolve
(E1
, Any_Integer
);
6386 Set_Etype
(N
, P_Base_Type
);
6388 -- Note, we need a range check in general, but we wait for the
6389 -- Resolve call to do this, since we want to let Eval_Attribute
6390 -- have a chance to find an static illegality first.
6397 when Attribute_Valid
=>
6400 -- Ignore check for object if we have a 'Valid reference generated
6401 -- by the expanded code, since in some cases valid checks can occur
6402 -- on items that are names, but are not objects (e.g. attributes).
6404 if Comes_From_Source
(N
) then
6405 Check_Object_Reference
(P
);
6408 if not Is_Scalar_Type
(P_Type
) then
6409 Error_Attr_P
("object for % attribute must be of scalar type");
6412 -- If the attribute appears within the subtype's own predicate
6413 -- function, then issue a warning that this will cause infinite
6417 Pred_Func
: constant Entity_Id
:= Predicate_Function
(P_Type
);
6420 if Present
(Pred_Func
) and then Current_Scope
= Pred_Func
then
6422 ("attribute Valid requires a predicate check??", N
);
6423 Error_Msg_N
("\and will result in infinite recursion??", N
);
6427 Set_Etype
(N
, Standard_Boolean
);
6433 when Attribute_Valid_Scalars
=>
6435 Check_Object_Reference
(P
);
6437 if No_Scalar_Parts
(P_Type
) then
6438 Error_Attr_P
("??attribute % always True, no scalars to check");
6441 Set_Etype
(N
, Standard_Boolean
);
6447 when Attribute_Value
=> Value
:
6449 Check_SPARK_Restriction_On_Attribute
;
6453 -- Case of enumeration type
6455 -- When an enumeration type appears in an attribute reference, all
6456 -- literals of the type are marked as referenced. This must only be
6457 -- done if the attribute reference appears in the current source.
6458 -- Otherwise the information on references may differ between a
6459 -- normal compilation and one that performs inlining.
6461 if Is_Enumeration_Type
(P_Type
)
6462 and then In_Extended_Main_Code_Unit
(N
)
6464 Check_Restriction
(No_Enumeration_Maps
, N
);
6466 -- Mark all enumeration literals as referenced, since the use of
6467 -- the Value attribute can implicitly reference any of the
6468 -- literals of the enumeration base type.
6471 Ent
: Entity_Id
:= First_Literal
(P_Base_Type
);
6473 while Present
(Ent
) loop
6474 Set_Referenced
(Ent
);
6480 -- Set Etype before resolving expression because expansion of
6481 -- expression may require enclosing type. Note that the type
6482 -- returned by 'Value is the base type of the prefix type.
6484 Set_Etype
(N
, P_Base_Type
);
6485 Validate_Non_Static_Attribute_Function_Call
;
6487 -- Check restriction No_Fixed_IO
6489 if Restriction_Check_Required
(No_Fixed_IO
)
6490 and then Is_Fixed_Point_Type
(P_Type
)
6492 Check_Restriction
(No_Fixed_IO
, P
);
6500 when Attribute_Value_Size
=>
6503 Check_Not_Incomplete_Type
;
6504 Set_Etype
(N
, Universal_Integer
);
6510 when Attribute_Version
=>
6513 Set_Etype
(N
, RTE
(RE_Version_String
));
6519 when Attribute_Wchar_T_Size
=>
6520 Standard_Attribute
(Interfaces_Wchar_T_Size
);
6526 when Attribute_Wide_Image
=> Wide_Image
:
6528 Check_SPARK_Restriction_On_Attribute
;
6530 Set_Etype
(N
, Standard_Wide_String
);
6532 Resolve
(E1
, P_Base_Type
);
6533 Validate_Non_Static_Attribute_Function_Call
;
6535 -- Check restriction No_Fixed_IO
6537 if Restriction_Check_Required
(No_Fixed_IO
)
6538 and then Is_Fixed_Point_Type
(P_Type
)
6540 Check_Restriction
(No_Fixed_IO
, P
);
6544 ---------------------
6545 -- Wide_Wide_Image --
6546 ---------------------
6548 when Attribute_Wide_Wide_Image
=> Wide_Wide_Image
:
6551 Set_Etype
(N
, Standard_Wide_Wide_String
);
6553 Resolve
(E1
, P_Base_Type
);
6554 Validate_Non_Static_Attribute_Function_Call
;
6556 -- Check restriction No_Fixed_IO
6558 if Restriction_Check_Required
(No_Fixed_IO
)
6559 and then Is_Fixed_Point_Type
(P_Type
)
6561 Check_Restriction
(No_Fixed_IO
, P
);
6563 end Wide_Wide_Image
;
6569 when Attribute_Wide_Value
=> Wide_Value
:
6571 Check_SPARK_Restriction_On_Attribute
;
6575 -- Set Etype before resolving expression because expansion
6576 -- of expression may require enclosing type.
6578 Set_Etype
(N
, P_Type
);
6579 Validate_Non_Static_Attribute_Function_Call
;
6581 -- Check restriction No_Fixed_IO
6583 if Restriction_Check_Required
(No_Fixed_IO
)
6584 and then Is_Fixed_Point_Type
(P_Type
)
6586 Check_Restriction
(No_Fixed_IO
, P
);
6590 ---------------------
6591 -- Wide_Wide_Value --
6592 ---------------------
6594 when Attribute_Wide_Wide_Value
=> Wide_Wide_Value
:
6599 -- Set Etype before resolving expression because expansion
6600 -- of expression may require enclosing type.
6602 Set_Etype
(N
, P_Type
);
6603 Validate_Non_Static_Attribute_Function_Call
;
6605 -- Check restriction No_Fixed_IO
6607 if Restriction_Check_Required
(No_Fixed_IO
)
6608 and then Is_Fixed_Point_Type
(P_Type
)
6610 Check_Restriction
(No_Fixed_IO
, P
);
6612 end Wide_Wide_Value
;
6614 ---------------------
6615 -- Wide_Wide_Width --
6616 ---------------------
6618 when Attribute_Wide_Wide_Width
=>
6621 Set_Etype
(N
, Universal_Integer
);
6627 when Attribute_Wide_Width
=>
6628 Check_SPARK_Restriction_On_Attribute
;
6631 Set_Etype
(N
, Universal_Integer
);
6637 when Attribute_Width
=>
6638 Check_SPARK_Restriction_On_Attribute
;
6641 Set_Etype
(N
, Universal_Integer
);
6647 when Attribute_Word_Size
=>
6648 Standard_Attribute
(System_Word_Size
);
6654 when Attribute_Write
=>
6656 Check_Stream_Attribute
(TSS_Stream_Write
);
6657 Set_Etype
(N
, Standard_Void_Type
);
6658 Resolve
(N
, Standard_Void_Type
);
6662 -- All errors raise Bad_Attribute, so that we get out before any further
6663 -- damage occurs when an error is detected (for example, if we check for
6664 -- one attribute expression, and the check succeeds, we want to be able
6665 -- to proceed securely assuming that an expression is in fact present.
6667 -- Note: we set the attribute analyzed in this case to prevent any
6668 -- attempt at reanalysis which could generate spurious error msgs.
6671 when Bad_Attribute
=>
6673 Set_Etype
(N
, Any_Type
);
6675 end Analyze_Attribute
;
6677 --------------------
6678 -- Eval_Attribute --
6679 --------------------
6681 procedure Eval_Attribute
(N
: Node_Id
) is
6682 Loc
: constant Source_Ptr
:= Sloc
(N
);
6683 Aname
: constant Name_Id
:= Attribute_Name
(N
);
6684 Id
: constant Attribute_Id
:= Get_Attribute_Id
(Aname
);
6685 P
: constant Node_Id
:= Prefix
(N
);
6687 C_Type
: constant Entity_Id
:= Etype
(N
);
6688 -- The type imposed by the context
6691 -- First expression, or Empty if none
6694 -- Second expression, or Empty if none
6696 P_Entity
: Entity_Id
;
6697 -- Entity denoted by prefix
6700 -- The type of the prefix
6702 P_Base_Type
: Entity_Id
;
6703 -- The base type of the prefix type
6705 P_Root_Type
: Entity_Id
;
6706 -- The root type of the prefix type
6709 -- True if the result is Static. This is set by the general processing
6710 -- to true if the prefix is static, and all expressions are static. It
6711 -- can be reset as processing continues for particular attributes
6713 Lo_Bound
, Hi_Bound
: Node_Id
;
6714 -- Expressions for low and high bounds of type or array index referenced
6715 -- by First, Last, or Length attribute for array, set by Set_Bounds.
6718 -- Constraint error node used if we have an attribute reference has
6719 -- an argument that raises a constraint error. In this case we replace
6720 -- the attribute with a raise constraint_error node. This is important
6721 -- processing, since otherwise gigi might see an attribute which it is
6722 -- unprepared to deal with.
6724 procedure Check_Concurrent_Discriminant
(Bound
: Node_Id
);
6725 -- If Bound is a reference to a discriminant of a task or protected type
6726 -- occurring within the object's body, rewrite attribute reference into
6727 -- a reference to the corresponding discriminal. Use for the expansion
6728 -- of checks against bounds of entry family index subtypes.
6730 procedure Check_Expressions
;
6731 -- In case where the attribute is not foldable, the expressions, if
6732 -- any, of the attribute, are in a non-static context. This procedure
6733 -- performs the required additional checks.
6735 function Compile_Time_Known_Bounds
(Typ
: Entity_Id
) return Boolean;
6736 -- Determines if the given type has compile time known bounds. Note
6737 -- that we enter the case statement even in cases where the prefix
6738 -- type does NOT have known bounds, so it is important to guard any
6739 -- attempt to evaluate both bounds with a call to this function.
6741 procedure Compile_Time_Known_Attribute
(N
: Node_Id
; Val
: Uint
);
6742 -- This procedure is called when the attribute N has a non-static
6743 -- but compile time known value given by Val. It includes the
6744 -- necessary checks for out of range values.
6746 function Fore_Value
return Nat
;
6747 -- Computes the Fore value for the current attribute prefix, which is
6748 -- known to be a static fixed-point type. Used by Fore and Width.
6750 function Is_VAX_Float
(Typ
: Entity_Id
) return Boolean;
6751 -- Determine whether Typ denotes a VAX floating point type
6753 function Mantissa
return Uint
;
6754 -- Returns the Mantissa value for the prefix type
6756 procedure Set_Bounds
;
6757 -- Used for First, Last and Length attributes applied to an array or
6758 -- array subtype. Sets the variables Lo_Bound and Hi_Bound to the low
6759 -- and high bound expressions for the index referenced by the attribute
6760 -- designator (i.e. the first index if no expression is present, and the
6761 -- N'th index if the value N is present as an expression). Also used for
6762 -- First and Last of scalar types and for First_Valid and Last_Valid.
6763 -- Static is reset to False if the type or index type is not statically
6766 function Statically_Denotes_Entity
(N
: Node_Id
) return Boolean;
6767 -- Verify that the prefix of a potentially static array attribute
6768 -- satisfies the conditions of 4.9 (14).
6770 -----------------------------------
6771 -- Check_Concurrent_Discriminant --
6772 -----------------------------------
6774 procedure Check_Concurrent_Discriminant
(Bound
: Node_Id
) is
6776 -- The concurrent (task or protected) type
6779 if Nkind
(Bound
) = N_Identifier
6780 and then Ekind
(Entity
(Bound
)) = E_Discriminant
6781 and then Is_Concurrent_Record_Type
(Scope
(Entity
(Bound
)))
6783 Tsk
:= Corresponding_Concurrent_Type
(Scope
(Entity
(Bound
)));
6785 if In_Open_Scopes
(Tsk
) and then Has_Completion
(Tsk
) then
6787 -- Find discriminant of original concurrent type, and use
6788 -- its current discriminal, which is the renaming within
6789 -- the task/protected body.
6793 (Find_Body_Discriminal
(Entity
(Bound
)), Loc
));
6796 end Check_Concurrent_Discriminant
;
6798 -----------------------
6799 -- Check_Expressions --
6800 -----------------------
6802 procedure Check_Expressions
is
6806 while Present
(E
) loop
6807 Check_Non_Static_Context
(E
);
6810 end Check_Expressions
;
6812 ----------------------------------
6813 -- Compile_Time_Known_Attribute --
6814 ----------------------------------
6816 procedure Compile_Time_Known_Attribute
(N
: Node_Id
; Val
: Uint
) is
6817 T
: constant Entity_Id
:= Etype
(N
);
6820 Fold_Uint
(N
, Val
, False);
6822 -- Check that result is in bounds of the type if it is static
6824 if Is_In_Range
(N
, T
, Assume_Valid
=> False) then
6827 elsif Is_Out_Of_Range
(N
, T
) then
6828 Apply_Compile_Time_Constraint_Error
6829 (N
, "value not in range of}??", CE_Range_Check_Failed
);
6831 elsif not Range_Checks_Suppressed
(T
) then
6832 Enable_Range_Check
(N
);
6835 Set_Do_Range_Check
(N
, False);
6837 end Compile_Time_Known_Attribute
;
6839 -------------------------------
6840 -- Compile_Time_Known_Bounds --
6841 -------------------------------
6843 function Compile_Time_Known_Bounds
(Typ
: Entity_Id
) return Boolean is
6846 Compile_Time_Known_Value
(Type_Low_Bound
(Typ
))
6848 Compile_Time_Known_Value
(Type_High_Bound
(Typ
));
6849 end Compile_Time_Known_Bounds
;
6855 -- Note that the Fore calculation is based on the actual values
6856 -- of the bounds, and does not take into account possible rounding.
6858 function Fore_Value
return Nat
is
6859 Lo
: constant Uint
:= Expr_Value
(Type_Low_Bound
(P_Type
));
6860 Hi
: constant Uint
:= Expr_Value
(Type_High_Bound
(P_Type
));
6861 Small
: constant Ureal
:= Small_Value
(P_Type
);
6862 Lo_Real
: constant Ureal
:= Lo
* Small
;
6863 Hi_Real
: constant Ureal
:= Hi
* Small
;
6868 -- Bounds are given in terms of small units, so first compute
6869 -- proper values as reals.
6871 T
:= UR_Max
(abs Lo_Real
, abs Hi_Real
);
6874 -- Loop to compute proper value if more than one digit required
6876 while T
>= Ureal_10
loop
6888 function Is_VAX_Float
(Typ
: Entity_Id
) return Boolean is
6891 Is_Floating_Point_Type
(Typ
)
6893 (Float_Format
= 'V' or else Float_Rep
(Typ
) = VAX_Native
);
6900 -- Table of mantissa values accessed by function Computed using
6903 -- T'Mantissa = integer next above (D * log(10)/log(2)) + 1)
6905 -- where D is T'Digits (RM83 3.5.7)
6907 Mantissa_Value
: constant array (Nat
range 1 .. 40) of Nat
:= (
6949 function Mantissa
return Uint
is
6952 UI_From_Int
(Mantissa_Value
(UI_To_Int
(Digits_Value
(P_Type
))));
6959 procedure Set_Bounds
is
6965 -- For a string literal subtype, we have to construct the bounds.
6966 -- Valid Ada code never applies attributes to string literals, but
6967 -- it is convenient to allow the expander to generate attribute
6968 -- references of this type (e.g. First and Last applied to a string
6971 -- Note that the whole point of the E_String_Literal_Subtype is to
6972 -- avoid this construction of bounds, but the cases in which we
6973 -- have to materialize them are rare enough that we don't worry.
6975 -- The low bound is simply the low bound of the base type. The
6976 -- high bound is computed from the length of the string and this
6979 if Ekind
(P_Type
) = E_String_Literal_Subtype
then
6980 Ityp
:= Etype
(First_Index
(Base_Type
(P_Type
)));
6981 Lo_Bound
:= Type_Low_Bound
(Ityp
);
6984 Make_Integer_Literal
(Sloc
(P
),
6986 Expr_Value
(Lo_Bound
) + String_Literal_Length
(P_Type
) - 1);
6988 Set_Parent
(Hi_Bound
, P
);
6989 Analyze_And_Resolve
(Hi_Bound
, Etype
(Lo_Bound
));
6992 -- For non-array case, just get bounds of scalar type
6994 elsif Is_Scalar_Type
(P_Type
) then
6997 -- For a fixed-point type, we must freeze to get the attributes
6998 -- of the fixed-point type set now so we can reference them.
7000 if Is_Fixed_Point_Type
(P_Type
)
7001 and then not Is_Frozen
(Base_Type
(P_Type
))
7002 and then Compile_Time_Known_Value
(Type_Low_Bound
(P_Type
))
7003 and then Compile_Time_Known_Value
(Type_High_Bound
(P_Type
))
7005 Freeze_Fixed_Point_Type
(Base_Type
(P_Type
));
7008 -- For array case, get type of proper index
7014 Ndim
:= UI_To_Int
(Expr_Value
(E1
));
7017 Indx
:= First_Index
(P_Type
);
7018 for J
in 1 .. Ndim
- 1 loop
7022 -- If no index type, get out (some other error occurred, and
7023 -- we don't have enough information to complete the job).
7031 Ityp
:= Etype
(Indx
);
7034 -- A discrete range in an index constraint is allowed to be a
7035 -- subtype indication. This is syntactically a pain, but should
7036 -- not propagate to the entity for the corresponding index subtype.
7037 -- After checking that the subtype indication is legal, the range
7038 -- of the subtype indication should be transfered to the entity.
7039 -- The attributes for the bounds should remain the simple retrievals
7040 -- that they are now.
7042 Lo_Bound
:= Type_Low_Bound
(Ityp
);
7043 Hi_Bound
:= Type_High_Bound
(Ityp
);
7045 if not Is_Static_Subtype
(Ityp
) then
7050 -------------------------------
7051 -- Statically_Denotes_Entity --
7052 -------------------------------
7054 function Statically_Denotes_Entity
(N
: Node_Id
) return Boolean is
7058 if not Is_Entity_Name
(N
) then
7065 Nkind
(Parent
(E
)) /= N_Object_Renaming_Declaration
7066 or else Statically_Denotes_Entity
(Renamed_Object
(E
));
7067 end Statically_Denotes_Entity
;
7069 -- Start of processing for Eval_Attribute
7072 -- Acquire first two expressions (at the moment, no attributes take more
7073 -- than two expressions in any case).
7075 if Present
(Expressions
(N
)) then
7076 E1
:= First
(Expressions
(N
));
7083 -- Special processing for Enabled attribute. This attribute has a very
7084 -- special prefix, and the easiest way to avoid lots of special checks
7085 -- to protect this special prefix from causing trouble is to deal with
7086 -- this attribute immediately and be done with it.
7088 if Id
= Attribute_Enabled
then
7090 -- We skip evaluation if the expander is not active. This is not just
7091 -- an optimization. It is of key importance that we not rewrite the
7092 -- attribute in a generic template, since we want to pick up the
7093 -- setting of the check in the instance, and testing expander active
7094 -- is as easy way of doing this as any.
7096 if Expander_Active
then
7098 C
: constant Check_Id
:= Get_Check_Id
(Chars
(P
));
7103 if C
in Predefined_Check_Id
then
7104 R
:= Scope_Suppress
.Suppress
(C
);
7106 R
:= Is_Check_Suppressed
(Empty
, C
);
7110 R
:= Is_Check_Suppressed
(Entity
(E1
), C
);
7113 Rewrite
(N
, New_Occurrence_Of
(Boolean_Literals
(not R
), Loc
));
7120 -- Special processing for cases where the prefix is an object. For
7121 -- this purpose, a string literal counts as an object (attributes
7122 -- of string literals can only appear in generated code).
7124 if Is_Object_Reference
(P
) or else Nkind
(P
) = N_String_Literal
then
7126 -- For Component_Size, the prefix is an array object, and we apply
7127 -- the attribute to the type of the object. This is allowed for
7128 -- both unconstrained and constrained arrays, since the bounds
7129 -- have no influence on the value of this attribute.
7131 if Id
= Attribute_Component_Size
then
7132 P_Entity
:= Etype
(P
);
7134 -- For First and Last, the prefix is an array object, and we apply
7135 -- the attribute to the type of the array, but we need a constrained
7136 -- type for this, so we use the actual subtype if available.
7138 elsif Id
= Attribute_First
7142 Id
= Attribute_Length
7145 AS
: constant Entity_Id
:= Get_Actual_Subtype_If_Available
(P
);
7148 if Present
(AS
) and then Is_Constrained
(AS
) then
7151 -- If we have an unconstrained type we cannot fold
7159 -- For Size, give size of object if available, otherwise we
7160 -- cannot fold Size.
7162 elsif Id
= Attribute_Size
then
7163 if Is_Entity_Name
(P
)
7164 and then Known_Esize
(Entity
(P
))
7166 Compile_Time_Known_Attribute
(N
, Esize
(Entity
(P
)));
7174 -- For Alignment, give size of object if available, otherwise we
7175 -- cannot fold Alignment.
7177 elsif Id
= Attribute_Alignment
then
7178 if Is_Entity_Name
(P
)
7179 and then Known_Alignment
(Entity
(P
))
7181 Fold_Uint
(N
, Alignment
(Entity
(P
)), False);
7189 -- For Lock_Free, we apply the attribute to the type of the object.
7190 -- This is allowed since we have already verified that the type is a
7193 elsif Id
= Attribute_Lock_Free
then
7194 P_Entity
:= Etype
(P
);
7196 -- No other attributes for objects are folded
7203 -- Cases where P is not an object. Cannot do anything if P is not the
7204 -- name of an entity.
7206 elsif not Is_Entity_Name
(P
) then
7210 -- Otherwise get prefix entity
7213 P_Entity
:= Entity
(P
);
7216 -- At this stage P_Entity is the entity to which the attribute
7217 -- is to be applied. This is usually simply the entity of the
7218 -- prefix, except in some cases of attributes for objects, where
7219 -- as described above, we apply the attribute to the object type.
7221 -- First foldable possibility is a scalar or array type (RM 4.9(7))
7222 -- that is not generic (generic types are eliminated by RM 4.9(25)).
7223 -- Note we allow non-static non-generic types at this stage as further
7226 if Is_Type
(P_Entity
)
7227 and then (Is_Scalar_Type
(P_Entity
) or Is_Array_Type
(P_Entity
))
7228 and then (not Is_Generic_Type
(P_Entity
))
7232 -- Second foldable possibility is an array object (RM 4.9(8))
7234 elsif (Ekind
(P_Entity
) = E_Variable
7236 Ekind
(P_Entity
) = E_Constant
)
7237 and then Is_Array_Type
(Etype
(P_Entity
))
7238 and then (not Is_Generic_Type
(Etype
(P_Entity
)))
7240 P_Type
:= Etype
(P_Entity
);
7242 -- If the entity is an array constant with an unconstrained nominal
7243 -- subtype then get the type from the initial value. If the value has
7244 -- been expanded into assignments, there is no expression and the
7245 -- attribute reference remains dynamic.
7247 -- We could do better here and retrieve the type ???
7249 if Ekind
(P_Entity
) = E_Constant
7250 and then not Is_Constrained
(P_Type
)
7252 if No
(Constant_Value
(P_Entity
)) then
7255 P_Type
:= Etype
(Constant_Value
(P_Entity
));
7259 -- Definite must be folded if the prefix is not a generic type,
7260 -- that is to say if we are within an instantiation. Same processing
7261 -- applies to the GNAT attributes Atomic_Always_Lock_Free,
7262 -- Has_Discriminants, Lock_Free, Type_Class, Has_Tagged_Value, and
7263 -- Unconstrained_Array.
7265 elsif (Id
= Attribute_Atomic_Always_Lock_Free
7267 Id
= Attribute_Definite
7269 Id
= Attribute_Has_Access_Values
7271 Id
= Attribute_Has_Discriminants
7273 Id
= Attribute_Has_Tagged_Values
7275 Id
= Attribute_Lock_Free
7277 Id
= Attribute_Type_Class
7279 Id
= Attribute_Unconstrained_Array
7281 Id
= Attribute_Max_Alignment_For_Allocation
)
7282 and then not Is_Generic_Type
(P_Entity
)
7286 -- We can fold 'Size applied to a type if the size is known (as happens
7287 -- for a size from an attribute definition clause). At this stage, this
7288 -- can happen only for types (e.g. record types) for which the size is
7289 -- always non-static. We exclude generic types from consideration (since
7290 -- they have bogus sizes set within templates).
7292 elsif Id
= Attribute_Size
7293 and then Is_Type
(P_Entity
)
7294 and then (not Is_Generic_Type
(P_Entity
))
7295 and then Known_Static_RM_Size
(P_Entity
)
7297 Compile_Time_Known_Attribute
(N
, RM_Size
(P_Entity
));
7300 -- We can fold 'Alignment applied to a type if the alignment is known
7301 -- (as happens for an alignment from an attribute definition clause).
7302 -- At this stage, this can happen only for types (e.g. record types) for
7303 -- which the size is always non-static. We exclude generic types from
7304 -- consideration (since they have bogus sizes set within templates).
7306 elsif Id
= Attribute_Alignment
7307 and then Is_Type
(P_Entity
)
7308 and then (not Is_Generic_Type
(P_Entity
))
7309 and then Known_Alignment
(P_Entity
)
7311 Compile_Time_Known_Attribute
(N
, Alignment
(P_Entity
));
7314 -- If this is an access attribute that is known to fail accessibility
7315 -- check, rewrite accordingly.
7317 elsif Attribute_Name
(N
) = Name_Access
7318 and then Raises_Constraint_Error
(N
)
7321 Make_Raise_Program_Error
(Loc
,
7322 Reason
=> PE_Accessibility_Check_Failed
));
7323 Set_Etype
(N
, C_Type
);
7326 -- No other cases are foldable (they certainly aren't static, and at
7327 -- the moment we don't try to fold any cases other than the ones above).
7334 -- If either attribute or the prefix is Any_Type, then propagate
7335 -- Any_Type to the result and don't do anything else at all.
7337 if P_Type
= Any_Type
7338 or else (Present
(E1
) and then Etype
(E1
) = Any_Type
)
7339 or else (Present
(E2
) and then Etype
(E2
) = Any_Type
)
7341 Set_Etype
(N
, Any_Type
);
7345 -- Scalar subtype case. We have not yet enforced the static requirement
7346 -- of (RM 4.9(7)) and we don't intend to just yet, since there are cases
7347 -- of non-static attribute references (e.g. S'Digits for a non-static
7348 -- floating-point type, which we can compute at compile time).
7350 -- Note: this folding of non-static attributes is not simply a case of
7351 -- optimization. For many of the attributes affected, Gigi cannot handle
7352 -- the attribute and depends on the front end having folded them away.
7354 -- Note: although we don't require staticness at this stage, we do set
7355 -- the Static variable to record the staticness, for easy reference by
7356 -- those attributes where it matters (e.g. Succ and Pred), and also to
7357 -- be used to ensure that non-static folded things are not marked as
7358 -- being static (a check that is done right at the end).
7360 P_Root_Type
:= Root_Type
(P_Type
);
7361 P_Base_Type
:= Base_Type
(P_Type
);
7363 -- If the root type or base type is generic, then we cannot fold. This
7364 -- test is needed because subtypes of generic types are not always
7365 -- marked as being generic themselves (which seems odd???)
7367 if Is_Generic_Type
(P_Root_Type
)
7368 or else Is_Generic_Type
(P_Base_Type
)
7373 if Is_Scalar_Type
(P_Type
) then
7374 Static
:= Is_OK_Static_Subtype
(P_Type
);
7376 -- Array case. We enforce the constrained requirement of (RM 4.9(7-8))
7377 -- since we can't do anything with unconstrained arrays. In addition,
7378 -- only the First, Last and Length attributes are possibly static.
7380 -- Atomic_Always_Lock_Free, Definite, Has_Access_Values,
7381 -- Has_Discriminants, Has_Tagged_Values, Lock_Free, Type_Class, and
7382 -- Unconstrained_Array are again exceptions, because they apply as well
7383 -- to unconstrained types.
7385 -- In addition Component_Size is an exception since it is possibly
7386 -- foldable, even though it is never static, and it does apply to
7387 -- unconstrained arrays. Furthermore, it is essential to fold this
7388 -- in the packed case, since otherwise the value will be incorrect.
7390 elsif Id
= Attribute_Atomic_Always_Lock_Free
7392 Id
= Attribute_Definite
7394 Id
= Attribute_Has_Access_Values
7396 Id
= Attribute_Has_Discriminants
7398 Id
= Attribute_Has_Tagged_Values
7400 Id
= Attribute_Lock_Free
7402 Id
= Attribute_Type_Class
7404 Id
= Attribute_Unconstrained_Array
7406 Id
= Attribute_Component_Size
7410 elsif Id
/= Attribute_Max_Alignment_For_Allocation
then
7411 if not Is_Constrained
(P_Type
)
7412 or else (Id
/= Attribute_First
and then
7413 Id
/= Attribute_Last
and then
7414 Id
/= Attribute_Length
)
7420 -- The rules in (RM 4.9(7,8)) require a static array, but as in the
7421 -- scalar case, we hold off on enforcing staticness, since there are
7422 -- cases which we can fold at compile time even though they are not
7423 -- static (e.g. 'Length applied to a static index, even though other
7424 -- non-static indexes make the array type non-static). This is only
7425 -- an optimization, but it falls out essentially free, so why not.
7426 -- Again we compute the variable Static for easy reference later
7427 -- (note that no array attributes are static in Ada 83).
7429 -- We also need to set Static properly for subsequent legality checks
7430 -- which might otherwise accept non-static constants in contexts
7431 -- where they are not legal.
7433 Static
:= Ada_Version
>= Ada_95
7434 and then Statically_Denotes_Entity
(P
);
7440 N
:= First_Index
(P_Type
);
7442 -- The expression is static if the array type is constrained
7443 -- by given bounds, and not by an initial expression. Constant
7444 -- strings are static in any case.
7446 if Root_Type
(P_Type
) /= Standard_String
then
7448 Static
and then not Is_Constr_Subt_For_U_Nominal
(P_Type
);
7451 while Present
(N
) loop
7452 Static
:= Static
and then Is_Static_Subtype
(Etype
(N
));
7454 -- If however the index type is generic, or derived from
7455 -- one, attributes cannot be folded.
7457 if Is_Generic_Type
(Root_Type
(Etype
(N
)))
7458 and then Id
/= Attribute_Component_Size
7468 -- Check any expressions that are present. Note that these expressions,
7469 -- depending on the particular attribute type, are either part of the
7470 -- attribute designator, or they are arguments in a case where the
7471 -- attribute reference returns a function. In the latter case, the
7472 -- rule in (RM 4.9(22)) applies and in particular requires the type
7473 -- of the expressions to be scalar in order for the attribute to be
7474 -- considered to be static.
7481 while Present
(E
) loop
7483 -- If expression is not static, then the attribute reference
7484 -- result certainly cannot be static.
7486 if not Is_Static_Expression
(E
) then
7490 -- If the result is not known at compile time, or is not of
7491 -- a scalar type, then the result is definitely not static,
7492 -- so we can quit now.
7494 if not Compile_Time_Known_Value
(E
)
7495 or else not Is_Scalar_Type
(Etype
(E
))
7497 -- An odd special case, if this is a Pos attribute, this
7498 -- is where we need to apply a range check since it does
7499 -- not get done anywhere else.
7501 if Id
= Attribute_Pos
then
7502 if Is_Integer_Type
(Etype
(E
)) then
7503 Apply_Range_Check
(E
, Etype
(N
));
7510 -- If the expression raises a constraint error, then so does
7511 -- the attribute reference. We keep going in this case because
7512 -- we are still interested in whether the attribute reference
7513 -- is static even if it is not static.
7515 elsif Raises_Constraint_Error
(E
) then
7516 Set_Raises_Constraint_Error
(N
);
7522 if Raises_Constraint_Error
(Prefix
(N
)) then
7527 -- Deal with the case of a static attribute reference that raises
7528 -- constraint error. The Raises_Constraint_Error flag will already
7529 -- have been set, and the Static flag shows whether the attribute
7530 -- reference is static. In any case we certainly can't fold such an
7531 -- attribute reference.
7533 -- Note that the rewriting of the attribute node with the constraint
7534 -- error node is essential in this case, because otherwise Gigi might
7535 -- blow up on one of the attributes it never expects to see.
7537 -- The constraint_error node must have the type imposed by the context,
7538 -- to avoid spurious errors in the enclosing expression.
7540 if Raises_Constraint_Error
(N
) then
7542 Make_Raise_Constraint_Error
(Sloc
(N
),
7543 Reason
=> CE_Range_Check_Failed
);
7544 Set_Etype
(CE_Node
, Etype
(N
));
7545 Set_Raises_Constraint_Error
(CE_Node
);
7547 Rewrite
(N
, Relocate_Node
(CE_Node
));
7548 Set_Is_Static_Expression
(N
, Static
);
7552 -- At this point we have a potentially foldable attribute reference.
7553 -- If Static is set, then the attribute reference definitely obeys
7554 -- the requirements in (RM 4.9(7,8,22)), and it definitely can be
7555 -- folded. If Static is not set, then the attribute may or may not
7556 -- be foldable, and the individual attribute processing routines
7557 -- test Static as required in cases where it makes a difference.
7559 -- In the case where Static is not set, we do know that all the
7560 -- expressions present are at least known at compile time (we assumed
7561 -- above that if this was not the case, then there was no hope of static
7562 -- evaluation). However, we did not require that the bounds of the
7563 -- prefix type be compile time known, let alone static). That's because
7564 -- there are many attributes that can be computed at compile time on
7565 -- non-static subtypes, even though such references are not static
7568 -- For VAX float, the root type is an IEEE type. So make sure to use the
7569 -- base type instead of the root-type for floating point attributes.
7573 -- Attributes related to Ada 2012 iterators (placeholder ???)
7575 when Attribute_Constant_Indexing |
7576 Attribute_Default_Iterator |
7577 Attribute_Implicit_Dereference |
7578 Attribute_Iterator_Element |
7579 Attribute_Iterable |
7580 Attribute_Variable_Indexing
=> null;
7582 -- Internal attributes used to deal with Ada 2012 delayed aspects.
7583 -- These were already rejected by the parser. Thus they shouldn't
7586 when Internal_Attribute_Id
=>
7587 raise Program_Error
;
7593 when Attribute_Adjacent
=>
7597 (P_Base_Type
, Expr_Value_R
(E1
), Expr_Value_R
(E2
)),
7604 when Attribute_Aft
=>
7605 Fold_Uint
(N
, Aft_Value
(P_Type
), True);
7611 when Attribute_Alignment
=> Alignment_Block
: declare
7612 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
7615 -- Fold if alignment is set and not otherwise
7617 if Known_Alignment
(P_TypeA
) then
7618 Fold_Uint
(N
, Alignment
(P_TypeA
), Is_Discrete_Type
(P_TypeA
));
7620 end Alignment_Block
;
7626 -- Can only be folded in No_Ast_Handler case
7628 when Attribute_AST_Entry
=>
7629 if not Is_AST_Entry
(P_Entity
) then
7631 New_Occurrence_Of
(RTE
(RE_No_AST_Handler
), Loc
));
7636 -----------------------------
7637 -- Atomic_Always_Lock_Free --
7638 -----------------------------
7640 -- Atomic_Always_Lock_Free attribute is a Boolean, thus no need to fold
7643 when Attribute_Atomic_Always_Lock_Free
=> Atomic_Always_Lock_Free
:
7645 V
: constant Entity_Id
:=
7647 (Support_Atomic_Primitives_On_Target
7648 and then Support_Atomic_Primitives
(P_Type
));
7651 Rewrite
(N
, New_Occurrence_Of
(V
, Loc
));
7653 -- Analyze and resolve as boolean. Note that this attribute is a
7654 -- static attribute in GNAT.
7656 Analyze_And_Resolve
(N
, Standard_Boolean
);
7658 end Atomic_Always_Lock_Free
;
7664 -- Bit can never be folded
7666 when Attribute_Bit
=>
7673 -- Body_version can never be static
7675 when Attribute_Body_Version
=>
7682 when Attribute_Ceiling
=>
7684 (N
, Eval_Fat
.Ceiling
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
7686 --------------------
7687 -- Component_Size --
7688 --------------------
7690 when Attribute_Component_Size
=>
7691 if Known_Static_Component_Size
(P_Type
) then
7692 Fold_Uint
(N
, Component_Size
(P_Type
), False);
7699 when Attribute_Compose
=>
7702 Eval_Fat
.Compose
(P_Base_Type
, Expr_Value_R
(E1
), Expr_Value
(E2
)),
7709 -- Constrained is never folded for now, there may be cases that
7710 -- could be handled at compile time. To be looked at later.
7712 when Attribute_Constrained
=>
7719 when Attribute_Copy_Sign
=>
7723 (P_Base_Type
, Expr_Value_R
(E1
), Expr_Value_R
(E2
)),
7730 when Attribute_Definite
=>
7731 Rewrite
(N
, New_Occurrence_Of
(
7732 Boolean_Literals
(not Is_Indefinite_Subtype
(P_Entity
)), Loc
));
7733 Analyze_And_Resolve
(N
, Standard_Boolean
);
7739 when Attribute_Delta
=>
7740 Fold_Ureal
(N
, Delta_Value
(P_Type
), True);
7746 when Attribute_Denorm
=>
7748 (N
, UI_From_Int
(Boolean'Pos (Has_Denormals
(P_Type
))), True);
7750 ---------------------
7751 -- Descriptor_Size --
7752 ---------------------
7754 when Attribute_Descriptor_Size
=>
7761 when Attribute_Digits
=>
7762 Fold_Uint
(N
, Digits_Value
(P_Type
), True);
7768 when Attribute_Emax
=>
7770 -- Ada 83 attribute is defined as (RM83 3.5.8)
7772 -- T'Emax = 4 * T'Mantissa
7774 Fold_Uint
(N
, 4 * Mantissa
, True);
7780 when Attribute_Enum_Rep
=>
7782 -- For an enumeration type with a non-standard representation use
7783 -- the Enumeration_Rep field of the proper constant. Note that this
7784 -- will not work for types Character/Wide_[Wide-]Character, since no
7785 -- real entities are created for the enumeration literals, but that
7786 -- does not matter since these two types do not have non-standard
7787 -- representations anyway.
7789 if Is_Enumeration_Type
(P_Type
)
7790 and then Has_Non_Standard_Rep
(P_Type
)
7792 Fold_Uint
(N
, Enumeration_Rep
(Expr_Value_E
(E1
)), Static
);
7794 -- For enumeration types with standard representations and all
7795 -- other cases (i.e. all integer and modular types), Enum_Rep
7796 -- is equivalent to Pos.
7799 Fold_Uint
(N
, Expr_Value
(E1
), Static
);
7806 when Attribute_Enum_Val
=> Enum_Val
: declare
7810 -- We have something like Enum_Type'Enum_Val (23), so search for a
7811 -- corresponding value in the list of Enum_Rep values for the type.
7813 Lit
:= First_Literal
(P_Base_Type
);
7815 if Enumeration_Rep
(Lit
) = Expr_Value
(E1
) then
7816 Fold_Uint
(N
, Enumeration_Pos
(Lit
), Static
);
7823 Apply_Compile_Time_Constraint_Error
7824 (N
, "no representation value matches",
7825 CE_Range_Check_Failed
,
7826 Warn
=> not Static
);
7836 when Attribute_Epsilon
=>
7838 -- Ada 83 attribute is defined as (RM83 3.5.8)
7840 -- T'Epsilon = 2.0**(1 - T'Mantissa)
7842 Fold_Ureal
(N
, Ureal_2
** (1 - Mantissa
), True);
7848 when Attribute_Exponent
=>
7850 Eval_Fat
.Exponent
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
7856 when Attribute_First
=> First_Attr
:
7860 if Compile_Time_Known_Value
(Lo_Bound
) then
7861 if Is_Real_Type
(P_Type
) then
7862 Fold_Ureal
(N
, Expr_Value_R
(Lo_Bound
), Static
);
7864 Fold_Uint
(N
, Expr_Value
(Lo_Bound
), Static
);
7867 -- Replace VAX Float_Type'First with a reference to the temporary
7868 -- which represents the low bound of the type. This transformation
7869 -- is needed since the back end cannot evaluate 'First on VAX.
7871 elsif Is_VAX_Float
(P_Type
)
7872 and then Nkind
(Lo_Bound
) = N_Identifier
7874 Rewrite
(N
, New_Occurrence_Of
(Entity
(Lo_Bound
), Sloc
(N
)));
7878 Check_Concurrent_Discriminant
(Lo_Bound
);
7886 when Attribute_First_Valid
=> First_Valid
:
7888 if Has_Predicates
(P_Type
)
7889 and then Present
(Static_Predicate
(P_Type
))
7892 FirstN
: constant Node_Id
:= First
(Static_Predicate
(P_Type
));
7894 if Nkind
(FirstN
) = N_Range
then
7895 Fold_Uint
(N
, Expr_Value
(Low_Bound
(FirstN
)), Static
);
7897 Fold_Uint
(N
, Expr_Value
(FirstN
), Static
);
7903 Fold_Uint
(N
, Expr_Value
(Lo_Bound
), Static
);
7911 when Attribute_Fixed_Value
=>
7918 when Attribute_Floor
=>
7920 (N
, Eval_Fat
.Floor
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
7926 when Attribute_Fore
=>
7927 if Compile_Time_Known_Bounds
(P_Type
) then
7928 Fold_Uint
(N
, UI_From_Int
(Fore_Value
), Static
);
7935 when Attribute_Fraction
=>
7937 (N
, Eval_Fat
.Fraction
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
7939 -----------------------
7940 -- Has_Access_Values --
7941 -----------------------
7943 when Attribute_Has_Access_Values
=>
7944 Rewrite
(N
, New_Occurrence_Of
7945 (Boolean_Literals
(Has_Access_Values
(P_Root_Type
)), Loc
));
7946 Analyze_And_Resolve
(N
, Standard_Boolean
);
7948 -----------------------
7949 -- Has_Discriminants --
7950 -----------------------
7952 when Attribute_Has_Discriminants
=>
7953 Rewrite
(N
, New_Occurrence_Of
(
7954 Boolean_Literals
(Has_Discriminants
(P_Entity
)), Loc
));
7955 Analyze_And_Resolve
(N
, Standard_Boolean
);
7957 -----------------------
7958 -- Has_Tagged_Values --
7959 -----------------------
7961 when Attribute_Has_Tagged_Values
=>
7962 Rewrite
(N
, New_Occurrence_Of
7963 (Boolean_Literals
(Has_Tagged_Component
(P_Root_Type
)), Loc
));
7964 Analyze_And_Resolve
(N
, Standard_Boolean
);
7970 when Attribute_Identity
=>
7977 -- Image is a scalar attribute, but is never static, because it is
7978 -- not a static function (having a non-scalar argument (RM 4.9(22))
7979 -- However, we can constant-fold the image of an enumeration literal
7980 -- if names are available.
7982 when Attribute_Image
=>
7983 if Is_Entity_Name
(E1
)
7984 and then Ekind
(Entity
(E1
)) = E_Enumeration_Literal
7985 and then not Discard_Names
(First_Subtype
(Etype
(E1
)))
7986 and then not Global_Discard_Names
7989 Lit
: constant Entity_Id
:= Entity
(E1
);
7993 Get_Unqualified_Decoded_Name_String
(Chars
(Lit
));
7994 Set_Casing
(All_Upper_Case
);
7995 Store_String_Chars
(Name_Buffer
(1 .. Name_Len
));
7997 Rewrite
(N
, Make_String_Literal
(Loc
, Strval
=> Str
));
7998 Analyze_And_Resolve
(N
, Standard_String
);
7999 Set_Is_Static_Expression
(N
, False);
8007 -- Img is a scalar attribute, but is never static, because it is
8008 -- not a static function (having a non-scalar argument (RM 4.9(22))
8010 when Attribute_Img
=>
8017 -- We never try to fold Integer_Value (though perhaps we could???)
8019 when Attribute_Integer_Value
=>
8026 -- Invalid_Value is a scalar attribute that is never static, because
8027 -- the value is by design out of range.
8029 when Attribute_Invalid_Value
=>
8036 when Attribute_Large
=>
8038 -- For fixed-point, we use the identity:
8040 -- T'Large = (2.0**T'Mantissa - 1.0) * T'Small
8042 if Is_Fixed_Point_Type
(P_Type
) then
8044 Make_Op_Multiply
(Loc
,
8046 Make_Op_Subtract
(Loc
,
8050 Make_Real_Literal
(Loc
, Ureal_2
),
8052 Make_Attribute_Reference
(Loc
,
8054 Attribute_Name
=> Name_Mantissa
)),
8055 Right_Opnd
=> Make_Real_Literal
(Loc
, Ureal_1
)),
8058 Make_Real_Literal
(Loc
, Small_Value
(Entity
(P
)))));
8060 Analyze_And_Resolve
(N
, C_Type
);
8062 -- Floating-point (Ada 83 compatibility)
8065 -- Ada 83 attribute is defined as (RM83 3.5.8)
8067 -- T'Large = 2.0**T'Emax * (1.0 - 2.0**(-T'Mantissa))
8071 -- T'Emax = 4 * T'Mantissa
8075 Ureal_2
** (4 * Mantissa
) * (Ureal_1
- Ureal_2
** (-Mantissa
)),
8083 when Attribute_Lock_Free
=> Lock_Free
: declare
8084 V
: constant Entity_Id
:= Boolean_Literals
(Uses_Lock_Free
(P_Type
));
8087 Rewrite
(N
, New_Occurrence_Of
(V
, Loc
));
8089 -- Analyze and resolve as boolean. Note that this attribute is a
8090 -- static attribute in GNAT.
8092 Analyze_And_Resolve
(N
, Standard_Boolean
);
8100 when Attribute_Last
=> Last_Attr
:
8104 if Compile_Time_Known_Value
(Hi_Bound
) then
8105 if Is_Real_Type
(P_Type
) then
8106 Fold_Ureal
(N
, Expr_Value_R
(Hi_Bound
), Static
);
8108 Fold_Uint
(N
, Expr_Value
(Hi_Bound
), Static
);
8111 -- Replace VAX Float_Type'Last with a reference to the temporary
8112 -- which represents the high bound of the type. This transformation
8113 -- is needed since the back end cannot evaluate 'Last on VAX.
8115 elsif Is_VAX_Float
(P_Type
)
8116 and then Nkind
(Hi_Bound
) = N_Identifier
8118 Rewrite
(N
, New_Occurrence_Of
(Entity
(Hi_Bound
), Sloc
(N
)));
8122 Check_Concurrent_Discriminant
(Hi_Bound
);
8130 when Attribute_Last_Valid
=> Last_Valid
:
8132 if Has_Predicates
(P_Type
)
8133 and then Present
(Static_Predicate
(P_Type
))
8136 LastN
: constant Node_Id
:= Last
(Static_Predicate
(P_Type
));
8138 if Nkind
(LastN
) = N_Range
then
8139 Fold_Uint
(N
, Expr_Value
(High_Bound
(LastN
)), Static
);
8141 Fold_Uint
(N
, Expr_Value
(LastN
), Static
);
8147 Fold_Uint
(N
, Expr_Value
(Hi_Bound
), Static
);
8155 when Attribute_Leading_Part
=>
8158 Eval_Fat
.Leading_Part
8159 (P_Base_Type
, Expr_Value_R
(E1
), Expr_Value
(E2
)),
8166 when Attribute_Length
=> Length
: declare
8170 -- If any index type is a formal type, or derived from one, the
8171 -- bounds are not static. Treating them as static can produce
8172 -- spurious warnings or improper constant folding.
8174 Ind
:= First_Index
(P_Type
);
8175 while Present
(Ind
) loop
8176 if Is_Generic_Type
(Root_Type
(Etype
(Ind
))) then
8185 -- For two compile time values, we can compute length
8187 if Compile_Time_Known_Value
(Lo_Bound
)
8188 and then Compile_Time_Known_Value
(Hi_Bound
)
8191 UI_Max
(0, 1 + (Expr_Value
(Hi_Bound
) - Expr_Value
(Lo_Bound
))),
8195 -- One more case is where Hi_Bound and Lo_Bound are compile-time
8196 -- comparable, and we can figure out the difference between them.
8199 Diff
: aliased Uint
;
8203 Compile_Time_Compare
8204 (Lo_Bound
, Hi_Bound
, Diff
'Access, Assume_Valid
=> False)
8207 Fold_Uint
(N
, Uint_1
, False);
8210 Fold_Uint
(N
, Uint_0
, False);
8213 if Diff
/= No_Uint
then
8214 Fold_Uint
(N
, Diff
+ 1, False);
8227 -- Loop_Entry acts as an alias of a constant initialized to the prefix
8228 -- of the said attribute at the point of entry into the related loop. As
8229 -- such, the attribute reference does not need to be evaluated because
8230 -- the prefix is the one that is evaluted.
8232 when Attribute_Loop_Entry
=>
8239 when Attribute_Machine
=>
8243 (P_Base_Type
, Expr_Value_R
(E1
), Eval_Fat
.Round
, N
),
8250 when Attribute_Machine_Emax
=>
8251 Fold_Uint
(N
, Machine_Emax_Value
(P_Type
), Static
);
8257 when Attribute_Machine_Emin
=>
8258 Fold_Uint
(N
, Machine_Emin_Value
(P_Type
), Static
);
8260 ----------------------
8261 -- Machine_Mantissa --
8262 ----------------------
8264 when Attribute_Machine_Mantissa
=>
8265 Fold_Uint
(N
, Machine_Mantissa_Value
(P_Type
), Static
);
8267 -----------------------
8268 -- Machine_Overflows --
8269 -----------------------
8271 when Attribute_Machine_Overflows
=>
8273 -- Always true for fixed-point
8275 if Is_Fixed_Point_Type
(P_Type
) then
8276 Fold_Uint
(N
, True_Value
, True);
8278 -- Floating point case
8282 UI_From_Int
(Boolean'Pos (Machine_Overflows_On_Target
)),
8290 when Attribute_Machine_Radix
=>
8291 if Is_Fixed_Point_Type
(P_Type
) then
8292 if Is_Decimal_Fixed_Point_Type
(P_Type
)
8293 and then Machine_Radix_10
(P_Type
)
8295 Fold_Uint
(N
, Uint_10
, True);
8297 Fold_Uint
(N
, Uint_2
, True);
8300 -- All floating-point type always have radix 2
8303 Fold_Uint
(N
, Uint_2
, True);
8306 ----------------------
8307 -- Machine_Rounding --
8308 ----------------------
8310 -- Note: for the folding case, it is fine to treat Machine_Rounding
8311 -- exactly the same way as Rounding, since this is one of the allowed
8312 -- behaviors, and performance is not an issue here. It might be a bit
8313 -- better to give the same result as it would give at run time, even
8314 -- though the non-determinism is certainly permitted.
8316 when Attribute_Machine_Rounding
=>
8318 (N
, Eval_Fat
.Rounding
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8320 --------------------
8321 -- Machine_Rounds --
8322 --------------------
8324 when Attribute_Machine_Rounds
=>
8326 -- Always False for fixed-point
8328 if Is_Fixed_Point_Type
(P_Type
) then
8329 Fold_Uint
(N
, False_Value
, True);
8331 -- Else yield proper floating-point result
8335 (N
, UI_From_Int
(Boolean'Pos (Machine_Rounds_On_Target
)), True);
8342 -- Note: Machine_Size is identical to Object_Size
8344 when Attribute_Machine_Size
=> Machine_Size
: declare
8345 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
8348 if Known_Esize
(P_TypeA
) then
8349 Fold_Uint
(N
, Esize
(P_TypeA
), True);
8357 when Attribute_Mantissa
=>
8359 -- Fixed-point mantissa
8361 if Is_Fixed_Point_Type
(P_Type
) then
8363 -- Compile time foldable case
8365 if Compile_Time_Known_Value
(Type_Low_Bound
(P_Type
))
8367 Compile_Time_Known_Value
(Type_High_Bound
(P_Type
))
8369 -- The calculation of the obsolete Ada 83 attribute Mantissa
8370 -- is annoying, because of AI00143, quoted here:
8372 -- !question 84-01-10
8374 -- Consider the model numbers for F:
8376 -- type F is delta 1.0 range -7.0 .. 8.0;
8378 -- The wording requires that F'MANTISSA be the SMALLEST
8379 -- integer number for which each bound of the specified
8380 -- range is either a model number or lies at most small
8381 -- distant from a model number. This means F'MANTISSA
8382 -- is required to be 3 since the range -7.0 .. 7.0 fits
8383 -- in 3 signed bits, and 8 is "at most" 1.0 from a model
8384 -- number, namely, 7. Is this analysis correct? Note that
8385 -- this implies the upper bound of the range is not
8386 -- represented as a model number.
8388 -- !response 84-03-17
8390 -- The analysis is correct. The upper and lower bounds for
8391 -- a fixed point type can lie outside the range of model
8402 LBound
:= Expr_Value_R
(Type_Low_Bound
(P_Type
));
8403 UBound
:= Expr_Value_R
(Type_High_Bound
(P_Type
));
8404 Bound
:= UR_Max
(UR_Abs
(LBound
), UR_Abs
(UBound
));
8405 Max_Man
:= UR_Trunc
(Bound
/ Small_Value
(P_Type
));
8407 -- If the Bound is exactly a model number, i.e. a multiple
8408 -- of Small, then we back it off by one to get the integer
8409 -- value that must be representable.
8411 if Small_Value
(P_Type
) * Max_Man
= Bound
then
8412 Max_Man
:= Max_Man
- 1;
8415 -- Now find corresponding size = Mantissa value
8418 while 2 ** Siz
< Max_Man
loop
8422 Fold_Uint
(N
, Siz
, True);
8426 -- The case of dynamic bounds cannot be evaluated at compile
8427 -- time. Instead we use a runtime routine (see Exp_Attr).
8432 -- Floating-point Mantissa
8435 Fold_Uint
(N
, Mantissa
, True);
8442 when Attribute_Max
=> Max
:
8444 if Is_Real_Type
(P_Type
) then
8446 (N
, UR_Max
(Expr_Value_R
(E1
), Expr_Value_R
(E2
)), Static
);
8448 Fold_Uint
(N
, UI_Max
(Expr_Value
(E1
), Expr_Value
(E2
)), Static
);
8452 ----------------------------------
8453 -- Max_Alignment_For_Allocation --
8454 ----------------------------------
8456 -- Max_Alignment_For_Allocation is usually the Alignment. However,
8457 -- arrays are allocated with dope, so we need to take into account both
8458 -- the alignment of the array, which comes from the component alignment,
8459 -- and the alignment of the dope. Also, if the alignment is unknown, we
8460 -- use the max (it's OK to be pessimistic).
8462 when Attribute_Max_Alignment_For_Allocation
=>
8464 A
: Uint
:= UI_From_Int
(Ttypes
.Maximum_Alignment
);
8466 if Known_Alignment
(P_Type
) and then
8467 (not Is_Array_Type
(P_Type
) or else Alignment
(P_Type
) > A
)
8469 A
:= Alignment
(P_Type
);
8472 Fold_Uint
(N
, A
, Static
);
8475 ----------------------------------
8476 -- Max_Size_In_Storage_Elements --
8477 ----------------------------------
8479 -- Max_Size_In_Storage_Elements is simply the Size rounded up to a
8480 -- Storage_Unit boundary. We can fold any cases for which the size
8481 -- is known by the front end.
8483 when Attribute_Max_Size_In_Storage_Elements
=>
8484 if Known_Esize
(P_Type
) then
8486 (Esize
(P_Type
) + System_Storage_Unit
- 1) /
8487 System_Storage_Unit
,
8491 --------------------
8492 -- Mechanism_Code --
8493 --------------------
8495 when Attribute_Mechanism_Code
=>
8499 Mech
: Mechanism_Type
;
8503 Mech
:= Mechanism
(P_Entity
);
8506 Val
:= UI_To_Int
(Expr_Value
(E1
));
8508 Formal
:= First_Formal
(P_Entity
);
8509 for J
in 1 .. Val
- 1 loop
8510 Next_Formal
(Formal
);
8512 Mech
:= Mechanism
(Formal
);
8516 Fold_Uint
(N
, UI_From_Int
(Int
(-Mech
)), True);
8524 when Attribute_Min
=> Min
:
8526 if Is_Real_Type
(P_Type
) then
8528 (N
, UR_Min
(Expr_Value_R
(E1
), Expr_Value_R
(E2
)), Static
);
8531 (N
, UI_Min
(Expr_Value
(E1
), Expr_Value
(E2
)), Static
);
8539 when Attribute_Mod
=>
8541 (N
, UI_Mod
(Expr_Value
(E1
), Modulus
(P_Base_Type
)), Static
);
8547 when Attribute_Model
=>
8549 (N
, Eval_Fat
.Model
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8555 when Attribute_Model_Emin
=>
8556 Fold_Uint
(N
, Model_Emin_Value
(P_Base_Type
), Static
);
8562 when Attribute_Model_Epsilon
=>
8563 Fold_Ureal
(N
, Model_Epsilon_Value
(P_Base_Type
), Static
);
8565 --------------------
8566 -- Model_Mantissa --
8567 --------------------
8569 when Attribute_Model_Mantissa
=>
8570 Fold_Uint
(N
, Model_Mantissa_Value
(P_Base_Type
), Static
);
8576 when Attribute_Model_Small
=>
8577 Fold_Ureal
(N
, Model_Small_Value
(P_Base_Type
), Static
);
8583 when Attribute_Modulus
=>
8584 Fold_Uint
(N
, Modulus
(P_Type
), True);
8586 --------------------
8587 -- Null_Parameter --
8588 --------------------
8590 -- Cannot fold, we know the value sort of, but the whole point is
8591 -- that there is no way to talk about this imaginary value except
8592 -- by using the attribute, so we leave it the way it is.
8594 when Attribute_Null_Parameter
=>
8601 -- The Object_Size attribute for a type returns the Esize of the
8602 -- type and can be folded if this value is known.
8604 when Attribute_Object_Size
=> Object_Size
: declare
8605 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
8608 if Known_Esize
(P_TypeA
) then
8609 Fold_Uint
(N
, Esize
(P_TypeA
), True);
8613 ----------------------
8614 -- Overlaps_Storage --
8615 ----------------------
8617 when Attribute_Overlaps_Storage
=>
8620 -------------------------
8621 -- Passed_By_Reference --
8622 -------------------------
8624 -- Scalar types are never passed by reference
8626 when Attribute_Passed_By_Reference
=>
8627 Fold_Uint
(N
, False_Value
, True);
8633 when Attribute_Pos
=>
8634 Fold_Uint
(N
, Expr_Value
(E1
), True);
8640 when Attribute_Pred
=> Pred
:
8642 -- Floating-point case
8644 if Is_Floating_Point_Type
(P_Type
) then
8646 (N
, Eval_Fat
.Pred
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8650 elsif Is_Fixed_Point_Type
(P_Type
) then
8652 (N
, Expr_Value_R
(E1
) - Small_Value
(P_Type
), True);
8654 -- Modular integer case (wraps)
8656 elsif Is_Modular_Integer_Type
(P_Type
) then
8657 Fold_Uint
(N
, (Expr_Value
(E1
) - 1) mod Modulus
(P_Type
), Static
);
8659 -- Other scalar cases
8662 pragma Assert
(Is_Scalar_Type
(P_Type
));
8664 if Is_Enumeration_Type
(P_Type
)
8665 and then Expr_Value
(E1
) =
8666 Expr_Value
(Type_Low_Bound
(P_Base_Type
))
8668 Apply_Compile_Time_Constraint_Error
8669 (N
, "Pred of `&''First`",
8670 CE_Overflow_Check_Failed
,
8672 Warn
=> not Static
);
8678 Fold_Uint
(N
, Expr_Value
(E1
) - 1, Static
);
8686 -- No processing required, because by this stage, Range has been
8687 -- replaced by First .. Last, so this branch can never be taken.
8689 when Attribute_Range
=>
8690 raise Program_Error
;
8696 when Attribute_Range_Length
=>
8699 -- Can fold if both bounds are compile time known
8701 if Compile_Time_Known_Value
(Hi_Bound
)
8702 and then Compile_Time_Known_Value
(Lo_Bound
)
8706 (0, Expr_Value
(Hi_Bound
) - Expr_Value
(Lo_Bound
) + 1),
8710 -- One more case is where Hi_Bound and Lo_Bound are compile-time
8711 -- comparable, and we can figure out the difference between them.
8714 Diff
: aliased Uint
;
8718 Compile_Time_Compare
8719 (Lo_Bound
, Hi_Bound
, Diff
'Access, Assume_Valid
=> False)
8722 Fold_Uint
(N
, Uint_1
, False);
8725 Fold_Uint
(N
, Uint_0
, False);
8728 if Diff
/= No_Uint
then
8729 Fold_Uint
(N
, Diff
+ 1, False);
8741 when Attribute_Ref
=>
8742 Fold_Uint
(N
, Expr_Value
(E1
), True);
8748 when Attribute_Remainder
=> Remainder
: declare
8749 X
: constant Ureal
:= Expr_Value_R
(E1
);
8750 Y
: constant Ureal
:= Expr_Value_R
(E2
);
8753 if UR_Is_Zero
(Y
) then
8754 Apply_Compile_Time_Constraint_Error
8755 (N
, "division by zero in Remainder",
8756 CE_Overflow_Check_Failed
,
8757 Warn
=> not Static
);
8763 Fold_Ureal
(N
, Eval_Fat
.Remainder
(P_Base_Type
, X
, Y
), Static
);
8770 when Attribute_Restriction_Set
=> Restriction_Set
: declare
8772 Rewrite
(N
, New_Occurrence_Of
(Standard_False
, Loc
));
8773 Set_Is_Static_Expression
(N
);
8774 end Restriction_Set
;
8780 when Attribute_Round
=> Round
:
8786 -- First we get the (exact result) in units of small
8788 Sr
:= Expr_Value_R
(E1
) / Small_Value
(C_Type
);
8790 -- Now round that exactly to an integer
8792 Si
:= UR_To_Uint
(Sr
);
8794 -- Finally the result is obtained by converting back to real
8796 Fold_Ureal
(N
, Si
* Small_Value
(C_Type
), Static
);
8803 when Attribute_Rounding
=>
8805 (N
, Eval_Fat
.Rounding
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8811 when Attribute_Safe_Emax
=>
8812 Fold_Uint
(N
, Safe_Emax_Value
(P_Type
), Static
);
8818 when Attribute_Safe_First
=>
8819 Fold_Ureal
(N
, Safe_First_Value
(P_Type
), Static
);
8825 when Attribute_Safe_Large
=>
8826 if Is_Fixed_Point_Type
(P_Type
) then
8828 (N
, Expr_Value_R
(Type_High_Bound
(P_Base_Type
)), Static
);
8830 Fold_Ureal
(N
, Safe_Last_Value
(P_Type
), Static
);
8837 when Attribute_Safe_Last
=>
8838 Fold_Ureal
(N
, Safe_Last_Value
(P_Type
), Static
);
8844 when Attribute_Safe_Small
=>
8846 -- In Ada 95, the old Ada 83 attribute Safe_Small is redundant
8847 -- for fixed-point, since is the same as Small, but we implement
8848 -- it for backwards compatibility.
8850 if Is_Fixed_Point_Type
(P_Type
) then
8851 Fold_Ureal
(N
, Small_Value
(P_Type
), Static
);
8853 -- Ada 83 Safe_Small for floating-point cases
8856 Fold_Ureal
(N
, Model_Small_Value
(P_Type
), Static
);
8863 when Attribute_Same_Storage
=>
8870 when Attribute_Scale
=>
8871 Fold_Uint
(N
, Scale_Value
(P_Type
), True);
8877 when Attribute_Scaling
=>
8881 (P_Base_Type
, Expr_Value_R
(E1
), Expr_Value
(E2
)),
8888 when Attribute_Signed_Zeros
=>
8890 (N
, UI_From_Int
(Boolean'Pos (Has_Signed_Zeros
(P_Type
))), Static
);
8896 -- Size attribute returns the RM size. All scalar types can be folded,
8897 -- as well as any types for which the size is known by the front end,
8898 -- including any type for which a size attribute is specified.
8900 when Attribute_Size | Attribute_VADS_Size
=> Size
: declare
8901 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
8904 if RM_Size
(P_TypeA
) /= Uint_0
then
8908 if Id
= Attribute_VADS_Size
or else Use_VADS_Size
then
8910 S
: constant Node_Id
:= Size_Clause
(P_TypeA
);
8913 -- If a size clause applies, then use the size from it.
8914 -- This is one of the rare cases where we can use the
8915 -- Size_Clause field for a subtype when Has_Size_Clause
8916 -- is False. Consider:
8918 -- type x is range 1 .. 64;
8919 -- for x'size use 12;
8920 -- subtype y is x range 0 .. 3;
8922 -- Here y has a size clause inherited from x, but normally
8923 -- it does not apply, and y'size is 2. However, y'VADS_Size
8924 -- is indeed 12 and not 2.
8927 and then Is_OK_Static_Expression
(Expression
(S
))
8929 Fold_Uint
(N
, Expr_Value
(Expression
(S
)), True);
8931 -- If no size is specified, then we simply use the object
8932 -- size in the VADS_Size case (e.g. Natural'Size is equal
8933 -- to Integer'Size, not one less).
8936 Fold_Uint
(N
, Esize
(P_TypeA
), True);
8940 -- Normal case (Size) in which case we want the RM_Size
8945 Static
and then Is_Discrete_Type
(P_TypeA
));
8954 when Attribute_Small
=>
8956 -- The floating-point case is present only for Ada 83 compatibility.
8957 -- Note that strictly this is an illegal addition, since we are
8958 -- extending an Ada 95 defined attribute, but we anticipate an
8959 -- ARG ruling that will permit this.
8961 if Is_Floating_Point_Type
(P_Type
) then
8963 -- Ada 83 attribute is defined as (RM83 3.5.8)
8965 -- T'Small = 2.0**(-T'Emax - 1)
8969 -- T'Emax = 4 * T'Mantissa
8971 Fold_Ureal
(N
, Ureal_2
** ((-(4 * Mantissa
)) - 1), Static
);
8973 -- Normal Ada 95 fixed-point case
8976 Fold_Ureal
(N
, Small_Value
(P_Type
), True);
8983 when Attribute_Stream_Size
=>
8990 when Attribute_Succ
=> Succ
:
8992 -- Floating-point case
8994 if Is_Floating_Point_Type
(P_Type
) then
8996 (N
, Eval_Fat
.Succ
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
9000 elsif Is_Fixed_Point_Type
(P_Type
) then
9001 Fold_Ureal
(N
, Expr_Value_R
(E1
) + Small_Value
(P_Type
), Static
);
9003 -- Modular integer case (wraps)
9005 elsif Is_Modular_Integer_Type
(P_Type
) then
9006 Fold_Uint
(N
, (Expr_Value
(E1
) + 1) mod Modulus
(P_Type
), Static
);
9008 -- Other scalar cases
9011 pragma Assert
(Is_Scalar_Type
(P_Type
));
9013 if Is_Enumeration_Type
(P_Type
)
9014 and then Expr_Value
(E1
) =
9015 Expr_Value
(Type_High_Bound
(P_Base_Type
))
9017 Apply_Compile_Time_Constraint_Error
9018 (N
, "Succ of `&''Last`",
9019 CE_Overflow_Check_Failed
,
9021 Warn
=> not Static
);
9026 Fold_Uint
(N
, Expr_Value
(E1
) + 1, Static
);
9035 when Attribute_Truncation
=>
9038 Eval_Fat
.Truncation
(P_Base_Type
, Expr_Value_R
(E1
)),
9045 when Attribute_Type_Class
=> Type_Class
: declare
9046 Typ
: constant Entity_Id
:= Underlying_Type
(P_Base_Type
);
9050 if Is_Descendent_Of_Address
(Typ
) then
9051 Id
:= RE_Type_Class_Address
;
9053 elsif Is_Enumeration_Type
(Typ
) then
9054 Id
:= RE_Type_Class_Enumeration
;
9056 elsif Is_Integer_Type
(Typ
) then
9057 Id
:= RE_Type_Class_Integer
;
9059 elsif Is_Fixed_Point_Type
(Typ
) then
9060 Id
:= RE_Type_Class_Fixed_Point
;
9062 elsif Is_Floating_Point_Type
(Typ
) then
9063 Id
:= RE_Type_Class_Floating_Point
;
9065 elsif Is_Array_Type
(Typ
) then
9066 Id
:= RE_Type_Class_Array
;
9068 elsif Is_Record_Type
(Typ
) then
9069 Id
:= RE_Type_Class_Record
;
9071 elsif Is_Access_Type
(Typ
) then
9072 Id
:= RE_Type_Class_Access
;
9074 elsif Is_Enumeration_Type
(Typ
) then
9075 Id
:= RE_Type_Class_Enumeration
;
9077 elsif Is_Task_Type
(Typ
) then
9078 Id
:= RE_Type_Class_Task
;
9080 -- We treat protected types like task types. It would make more
9081 -- sense to have another enumeration value, but after all the
9082 -- whole point of this feature is to be exactly DEC compatible,
9083 -- and changing the type Type_Class would not meet this requirement.
9085 elsif Is_Protected_Type
(Typ
) then
9086 Id
:= RE_Type_Class_Task
;
9088 -- Not clear if there are any other possibilities, but if there
9089 -- are, then we will treat them as the address case.
9092 Id
:= RE_Type_Class_Address
;
9095 Rewrite
(N
, New_Occurrence_Of
(RTE
(Id
), Loc
));
9098 -----------------------
9099 -- Unbiased_Rounding --
9100 -----------------------
9102 when Attribute_Unbiased_Rounding
=>
9105 Eval_Fat
.Unbiased_Rounding
(P_Base_Type
, Expr_Value_R
(E1
)),
9108 -------------------------
9109 -- Unconstrained_Array --
9110 -------------------------
9112 when Attribute_Unconstrained_Array
=> Unconstrained_Array
: declare
9113 Typ
: constant Entity_Id
:= Underlying_Type
(P_Type
);
9116 Rewrite
(N
, New_Occurrence_Of
(
9118 Is_Array_Type
(P_Type
)
9119 and then not Is_Constrained
(Typ
)), Loc
));
9121 -- Analyze and resolve as boolean, note that this attribute is
9122 -- a static attribute in GNAT.
9124 Analyze_And_Resolve
(N
, Standard_Boolean
);
9126 end Unconstrained_Array
;
9128 -- Attribute Update is never static
9130 when Attribute_Update
=>
9137 -- Processing is shared with Size
9143 when Attribute_Val
=> Val
:
9145 if Expr_Value
(E1
) < Expr_Value
(Type_Low_Bound
(P_Base_Type
))
9147 Expr_Value
(E1
) > Expr_Value
(Type_High_Bound
(P_Base_Type
))
9149 Apply_Compile_Time_Constraint_Error
9150 (N
, "Val expression out of range",
9151 CE_Range_Check_Failed
,
9152 Warn
=> not Static
);
9158 Fold_Uint
(N
, Expr_Value
(E1
), Static
);
9166 -- The Value_Size attribute for a type returns the RM size of the
9167 -- type. This an always be folded for scalar types, and can also
9168 -- be folded for non-scalar types if the size is set.
9170 when Attribute_Value_Size
=> Value_Size
: declare
9171 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
9173 if RM_Size
(P_TypeA
) /= Uint_0
then
9174 Fold_Uint
(N
, RM_Size
(P_TypeA
), True);
9182 -- Version can never be static
9184 when Attribute_Version
=>
9191 -- Wide_Image is a scalar attribute, but is never static, because it
9192 -- is not a static function (having a non-scalar argument (RM 4.9(22))
9194 when Attribute_Wide_Image
=>
9197 ---------------------
9198 -- Wide_Wide_Image --
9199 ---------------------
9201 -- Wide_Wide_Image is a scalar attribute but is never static, because it
9202 -- is not a static function (having a non-scalar argument (RM 4.9(22)).
9204 when Attribute_Wide_Wide_Image
=>
9207 ---------------------
9208 -- Wide_Wide_Width --
9209 ---------------------
9211 -- Processing for Wide_Wide_Width is combined with Width
9217 -- Processing for Wide_Width is combined with Width
9223 -- This processing also handles the case of Wide_[Wide_]Width
9225 when Attribute_Width |
9226 Attribute_Wide_Width |
9227 Attribute_Wide_Wide_Width
=> Width
:
9229 if Compile_Time_Known_Bounds
(P_Type
) then
9231 -- Floating-point types
9233 if Is_Floating_Point_Type
(P_Type
) then
9235 -- Width is zero for a null range (RM 3.5 (38))
9237 if Expr_Value_R
(Type_High_Bound
(P_Type
)) <
9238 Expr_Value_R
(Type_Low_Bound
(P_Type
))
9240 Fold_Uint
(N
, Uint_0
, True);
9243 -- For floating-point, we have +N.dddE+nnn where length
9244 -- of ddd is determined by type'Digits - 1, but is one
9245 -- if Digits is one (RM 3.5 (33)).
9247 -- nnn is set to 2 for Short_Float and Float (32 bit
9248 -- floats), and 3 for Long_Float and Long_Long_Float.
9249 -- For machines where Long_Long_Float is the IEEE
9250 -- extended precision type, the exponent takes 4 digits.
9254 Int
'Max (2, UI_To_Int
(Digits_Value
(P_Type
)));
9257 if Esize
(P_Type
) <= 32 then
9259 elsif Esize
(P_Type
) = 64 then
9265 Fold_Uint
(N
, UI_From_Int
(Len
), True);
9269 -- Fixed-point types
9271 elsif Is_Fixed_Point_Type
(P_Type
) then
9273 -- Width is zero for a null range (RM 3.5 (38))
9275 if Expr_Value
(Type_High_Bound
(P_Type
)) <
9276 Expr_Value
(Type_Low_Bound
(P_Type
))
9278 Fold_Uint
(N
, Uint_0
, True);
9280 -- The non-null case depends on the specific real type
9283 -- For fixed-point type width is Fore + 1 + Aft (RM 3.5(34))
9286 (N
, UI_From_Int
(Fore_Value
+ 1) + Aft_Value
(P_Type
),
9294 R
: constant Entity_Id
:= Root_Type
(P_Type
);
9295 Lo
: constant Uint
:= Expr_Value
(Type_Low_Bound
(P_Type
));
9296 Hi
: constant Uint
:= Expr_Value
(Type_High_Bound
(P_Type
));
9309 -- Width for types derived from Standard.Character
9310 -- and Standard.Wide_[Wide_]Character.
9312 elsif Is_Standard_Character_Type
(P_Type
) then
9315 -- Set W larger if needed
9317 for J
in UI_To_Int
(Lo
) .. UI_To_Int
(Hi
) loop
9319 -- All wide characters look like Hex_hhhhhhhh
9323 -- No need to compute this more than once
9328 C
:= Character'Val (J
);
9330 -- Test for all cases where Character'Image
9331 -- yields an image that is longer than three
9332 -- characters. First the cases of Reserved_xxx
9333 -- names (length = 12).
9336 when Reserved_128 | Reserved_129 |
9337 Reserved_132 | Reserved_153
9340 when BS | HT | LF | VT | FF | CR |
9341 SO | SI | EM | FS | GS | RS |
9342 US | RI | MW | ST | PM
9345 when NUL | SOH | STX | ETX | EOT |
9346 ENQ | ACK | BEL | DLE | DC1 |
9347 DC2 | DC3 | DC4 | NAK | SYN |
9348 ETB | CAN | SUB | ESC | DEL |
9349 BPH | NBH | NEL | SSA | ESA |
9350 HTS | HTJ | VTS | PLD | PLU |
9351 SS2 | SS3 | DCS | PU1 | PU2 |
9352 STS | CCH | SPA | EPA | SOS |
9353 SCI | CSI | OSC | APC
9356 when Space
.. Tilde |
9357 No_Break_Space
.. LC_Y_Diaeresis
9359 -- Special case of soft hyphen in Ada 2005
9361 if C
= Character'Val (16#AD#
)
9362 and then Ada_Version
>= Ada_2005
9370 W
:= Int
'Max (W
, Wt
);
9374 -- Width for types derived from Standard.Boolean
9376 elsif R
= Standard_Boolean
then
9383 -- Width for integer types
9385 elsif Is_Integer_Type
(P_Type
) then
9386 T
:= UI_Max
(abs Lo
, abs Hi
);
9394 -- User declared enum type with discard names
9396 elsif Discard_Names
(R
) then
9398 -- If range is null, result is zero, that has already
9399 -- been dealt with, so what we need is the power of ten
9400 -- that accomodates the Pos of the largest value, which
9401 -- is the high bound of the range + one for the space.
9410 -- Only remaining possibility is user declared enum type
9411 -- with normal case of Discard_Names not active.
9414 pragma Assert
(Is_Enumeration_Type
(P_Type
));
9417 L
:= First_Literal
(P_Type
);
9418 while Present
(L
) loop
9420 -- Only pay attention to in range characters
9422 if Lo
<= Enumeration_Pos
(L
)
9423 and then Enumeration_Pos
(L
) <= Hi
9425 -- For Width case, use decoded name
9427 if Id
= Attribute_Width
then
9428 Get_Decoded_Name_String
(Chars
(L
));
9429 Wt
:= Nat
(Name_Len
);
9431 -- For Wide_[Wide_]Width, use encoded name, and
9432 -- then adjust for the encoding.
9435 Get_Name_String
(Chars
(L
));
9437 -- Character literals are always of length 3
9439 if Name_Buffer
(1) = 'Q' then
9442 -- Otherwise loop to adjust for upper/wide chars
9445 Wt
:= Nat
(Name_Len
);
9447 for J
in 1 .. Name_Len
loop
9448 if Name_Buffer
(J
) = 'U' then
9450 elsif Name_Buffer
(J
) = 'W' then
9457 W
:= Int
'Max (W
, Wt
);
9464 Fold_Uint
(N
, UI_From_Int
(W
), True);
9470 -- The following attributes denote functions that cannot be folded
9472 when Attribute_From_Any |
9474 Attribute_TypeCode
=>
9477 -- The following attributes can never be folded, and furthermore we
9478 -- should not even have entered the case statement for any of these.
9479 -- Note that in some cases, the values have already been folded as
9480 -- a result of the processing in Analyze_Attribute.
9482 when Attribute_Abort_Signal |
9485 Attribute_Address_Size |
9486 Attribute_Asm_Input |
9487 Attribute_Asm_Output |
9489 Attribute_Bit_Order |
9490 Attribute_Bit_Position |
9491 Attribute_Callable |
9494 Attribute_Code_Address |
9495 Attribute_Compiler_Version |
9497 Attribute_Default_Bit_Order |
9498 Attribute_Elaborated |
9499 Attribute_Elab_Body |
9500 Attribute_Elab_Spec |
9501 Attribute_Elab_Subp_Body |
9503 Attribute_External_Tag |
9504 Attribute_Fast_Math |
9505 Attribute_First_Bit |
9507 Attribute_Last_Bit |
9508 Attribute_Library_Level |
9509 Attribute_Maximum_Alignment |
9512 Attribute_Partition_ID |
9513 Attribute_Pool_Address |
9514 Attribute_Position |
9515 Attribute_Priority |
9518 Attribute_Scalar_Storage_Order |
9519 Attribute_Simple_Storage_Pool |
9520 Attribute_Storage_Pool |
9521 Attribute_Storage_Size |
9522 Attribute_Storage_Unit |
9523 Attribute_Stub_Type |
9524 Attribute_System_Allocator_Alignment |
9526 Attribute_Target_Name |
9527 Attribute_Terminated |
9528 Attribute_To_Address |
9529 Attribute_Type_Key |
9530 Attribute_UET_Address |
9531 Attribute_Unchecked_Access |
9532 Attribute_Universal_Literal_String |
9533 Attribute_Unrestricted_Access |
9535 Attribute_Valid_Scalars |
9537 Attribute_Wchar_T_Size |
9538 Attribute_Wide_Value |
9539 Attribute_Wide_Wide_Value |
9540 Attribute_Word_Size |
9543 raise Program_Error
;
9546 -- At the end of the case, one more check. If we did a static evaluation
9547 -- so that the result is now a literal, then set Is_Static_Expression
9548 -- in the constant only if the prefix type is a static subtype. For
9549 -- non-static subtypes, the folding is still OK, but not static.
9551 -- An exception is the GNAT attribute Constrained_Array which is
9552 -- defined to be a static attribute in all cases.
9554 if Nkind_In
(N
, N_Integer_Literal
,
9556 N_Character_Literal
,
9558 or else (Is_Entity_Name
(N
)
9559 and then Ekind
(Entity
(N
)) = E_Enumeration_Literal
)
9561 Set_Is_Static_Expression
(N
, Static
);
9563 -- If this is still an attribute reference, then it has not been folded
9564 -- and that means that its expressions are in a non-static context.
9566 elsif Nkind
(N
) = N_Attribute_Reference
then
9569 -- Note: the else case not covered here are odd cases where the
9570 -- processing has transformed the attribute into something other
9571 -- than a constant. Nothing more to do in such cases.
9578 ------------------------------
9579 -- Is_Anonymous_Tagged_Base --
9580 ------------------------------
9582 function Is_Anonymous_Tagged_Base
9589 Anon
= Current_Scope
9590 and then Is_Itype
(Anon
)
9591 and then Associated_Node_For_Itype
(Anon
) = Parent
(Typ
);
9592 end Is_Anonymous_Tagged_Base
;
9594 --------------------------------
9595 -- Name_Implies_Lvalue_Prefix --
9596 --------------------------------
9598 function Name_Implies_Lvalue_Prefix
(Nam
: Name_Id
) return Boolean is
9599 pragma Assert
(Is_Attribute_Name
(Nam
));
9601 return Attribute_Name_Implies_Lvalue_Prefix
(Get_Attribute_Id
(Nam
));
9602 end Name_Implies_Lvalue_Prefix
;
9604 -----------------------
9605 -- Resolve_Attribute --
9606 -----------------------
9608 procedure Resolve_Attribute
(N
: Node_Id
; Typ
: Entity_Id
) is
9609 Loc
: constant Source_Ptr
:= Sloc
(N
);
9610 P
: constant Node_Id
:= Prefix
(N
);
9611 Aname
: constant Name_Id
:= Attribute_Name
(N
);
9612 Attr_Id
: constant Attribute_Id
:= Get_Attribute_Id
(Aname
);
9613 Btyp
: constant Entity_Id
:= Base_Type
(Typ
);
9614 Des_Btyp
: Entity_Id
;
9615 Index
: Interp_Index
;
9617 Nom_Subt
: Entity_Id
;
9619 procedure Accessibility_Message
;
9620 -- Error, or warning within an instance, if the static accessibility
9621 -- rules of 3.10.2 are violated.
9623 ---------------------------
9624 -- Accessibility_Message --
9625 ---------------------------
9627 procedure Accessibility_Message
is
9628 Indic
: Node_Id
:= Parent
(Parent
(N
));
9631 -- In an instance, this is a runtime check, but one we
9632 -- know will fail, so generate an appropriate warning.
9634 if In_Instance_Body
then
9635 Error_Msg_Warn
:= SPARK_Mode
/= On
;
9637 ("non-local pointer cannot point to local object<<", P
);
9638 Error_Msg_F
("\Program_Error [<<", P
);
9640 Make_Raise_Program_Error
(Loc
,
9641 Reason
=> PE_Accessibility_Check_Failed
));
9646 Error_Msg_F
("non-local pointer cannot point to local object", P
);
9648 -- Check for case where we have a missing access definition
9650 if Is_Record_Type
(Current_Scope
)
9652 Nkind_In
(Parent
(N
), N_Discriminant_Association
,
9653 N_Index_Or_Discriminant_Constraint
)
9655 Indic
:= Parent
(Parent
(N
));
9656 while Present
(Indic
)
9657 and then Nkind
(Indic
) /= N_Subtype_Indication
9659 Indic
:= Parent
(Indic
);
9662 if Present
(Indic
) then
9664 ("\use an access definition for" &
9665 " the access discriminant of&",
9666 N
, Entity
(Subtype_Mark
(Indic
)));
9670 end Accessibility_Message
;
9672 -- Start of processing for Resolve_Attribute
9675 -- If error during analysis, no point in continuing, except for array
9676 -- types, where we get better recovery by using unconstrained indexes
9677 -- than nothing at all (see Check_Array_Type).
9680 and then Attr_Id
/= Attribute_First
9681 and then Attr_Id
/= Attribute_Last
9682 and then Attr_Id
/= Attribute_Length
9683 and then Attr_Id
/= Attribute_Range
9688 -- If attribute was universal type, reset to actual type
9690 if Etype
(N
) = Universal_Integer
9691 or else Etype
(N
) = Universal_Real
9696 -- Remaining processing depends on attribute
9704 -- For access attributes, if the prefix denotes an entity, it is
9705 -- interpreted as a name, never as a call. It may be overloaded,
9706 -- in which case resolution uses the profile of the context type.
9707 -- Otherwise prefix must be resolved.
9709 when Attribute_Access
9710 | Attribute_Unchecked_Access
9711 | Attribute_Unrestricted_Access
=>
9715 if Is_Variable
(P
) then
9716 Note_Possible_Modification
(P
, Sure
=> False);
9719 -- The following comes from a query by Adam Beneschan, concerning
9720 -- improper use of universal_access in equality tests involving
9721 -- anonymous access types. Another good reason for 'Ref, but
9722 -- for now disable the test, which breaks several filed tests.
9724 if Ekind
(Typ
) = E_Anonymous_Access_Type
9725 and then Nkind_In
(Parent
(N
), N_Op_Eq
, N_Op_Ne
)
9728 Error_Msg_N
("need unique type to resolve 'Access", N
);
9729 Error_Msg_N
("\qualify attribute with some access type", N
);
9732 if Is_Entity_Name
(P
) then
9733 if Is_Overloaded
(P
) then
9734 Get_First_Interp
(P
, Index
, It
);
9735 while Present
(It
.Nam
) loop
9736 if Type_Conformant
(Designated_Type
(Typ
), It
.Nam
) then
9737 Set_Entity
(P
, It
.Nam
);
9739 -- The prefix is definitely NOT overloaded anymore at
9740 -- this point, so we reset the Is_Overloaded flag to
9741 -- avoid any confusion when reanalyzing the node.
9743 Set_Is_Overloaded
(P
, False);
9744 Set_Is_Overloaded
(N
, False);
9745 Generate_Reference
(Entity
(P
), P
);
9749 Get_Next_Interp
(Index
, It
);
9752 -- If Prefix is a subprogram name, this reference freezes:
9754 -- If it is a type, there is nothing to resolve.
9755 -- If it is an object, complete its resolution.
9757 elsif Is_Overloadable
(Entity
(P
)) then
9759 -- Avoid insertion of freeze actions in spec expression mode
9761 if not In_Spec_Expression
then
9762 Freeze_Before
(N
, Entity
(P
));
9765 elsif Is_Type
(Entity
(P
)) then
9771 Error_Msg_Name_1
:= Aname
;
9773 if not Is_Entity_Name
(P
) then
9776 elsif Is_Overloadable
(Entity
(P
))
9777 and then Is_Abstract_Subprogram
(Entity
(P
))
9779 Error_Msg_F
("prefix of % attribute cannot be abstract", P
);
9780 Set_Etype
(N
, Any_Type
);
9782 elsif Ekind
(Entity
(P
)) = E_Enumeration_Literal
then
9784 ("prefix of % attribute cannot be enumeration literal", P
);
9785 Set_Etype
(N
, Any_Type
);
9787 -- An attempt to take 'Access of a function that renames an
9788 -- enumeration literal. Issue a specialized error message.
9790 elsif Ekind
(Entity
(P
)) = E_Function
9791 and then Present
(Alias
(Entity
(P
)))
9792 and then Ekind
(Alias
(Entity
(P
))) = E_Enumeration_Literal
9795 ("prefix of % attribute cannot be function renaming "
9796 & "an enumeration literal", P
);
9797 Set_Etype
(N
, Any_Type
);
9799 elsif Convention
(Entity
(P
)) = Convention_Intrinsic
then
9800 Error_Msg_F
("prefix of % attribute cannot be intrinsic", P
);
9801 Set_Etype
(N
, Any_Type
);
9804 -- Assignments, return statements, components of aggregates,
9805 -- generic instantiations will require convention checks if
9806 -- the type is an access to subprogram. Given that there will
9807 -- also be accessibility checks on those, this is where the
9808 -- checks can eventually be centralized ???
9810 if Ekind_In
(Btyp
, E_Access_Subprogram_Type
,
9811 E_Anonymous_Access_Subprogram_Type
,
9812 E_Access_Protected_Subprogram_Type
,
9813 E_Anonymous_Access_Protected_Subprogram_Type
)
9815 -- Deal with convention mismatch
9817 if Convention
(Designated_Type
(Btyp
)) /=
9818 Convention
(Entity
(P
))
9821 ("subprogram & has wrong convention", P
, Entity
(P
));
9822 Error_Msg_Sloc
:= Sloc
(Btyp
);
9823 Error_Msg_FE
("\does not match & declared#", P
, Btyp
);
9825 if not Is_Itype
(Btyp
)
9826 and then not Has_Convention_Pragma
(Btyp
)
9829 ("\probable missing pragma Convention for &",
9834 Check_Subtype_Conformant
9835 (New_Id
=> Entity
(P
),
9836 Old_Id
=> Designated_Type
(Btyp
),
9840 if Attr_Id
= Attribute_Unchecked_Access
then
9841 Error_Msg_Name_1
:= Aname
;
9843 ("attribute% cannot be applied to a subprogram", P
);
9845 elsif Aname
= Name_Unrestricted_Access
then
9846 null; -- Nothing to check
9848 -- Check the static accessibility rule of 3.10.2(32).
9849 -- This rule also applies within the private part of an
9850 -- instantiation. This rule does not apply to anonymous
9851 -- access-to-subprogram types in access parameters.
9853 elsif Attr_Id
= Attribute_Access
9854 and then not In_Instance_Body
9856 (Ekind
(Btyp
) = E_Access_Subprogram_Type
9857 or else Is_Local_Anonymous_Access
(Btyp
))
9858 and then Subprogram_Access_Level
(Entity
(P
)) >
9859 Type_Access_Level
(Btyp
)
9862 ("subprogram must not be deeper than access type", P
);
9864 -- Check the restriction of 3.10.2(32) that disallows the
9865 -- access attribute within a generic body when the ultimate
9866 -- ancestor of the type of the attribute is declared outside
9867 -- of the generic unit and the subprogram is declared within
9868 -- that generic unit. This includes any such attribute that
9869 -- occurs within the body of a generic unit that is a child
9870 -- of the generic unit where the subprogram is declared.
9872 -- The rule also prohibits applying the attribute when the
9873 -- access type is a generic formal access type (since the
9874 -- level of the actual type is not known). This restriction
9875 -- does not apply when the attribute type is an anonymous
9876 -- access-to-subprogram type. Note that this check was
9877 -- revised by AI-229, because the originally Ada 95 rule
9878 -- was too lax. The original rule only applied when the
9879 -- subprogram was declared within the body of the generic,
9880 -- which allowed the possibility of dangling references).
9881 -- The rule was also too strict in some case, in that it
9882 -- didn't permit the access to be declared in the generic
9883 -- spec, whereas the revised rule does (as long as it's not
9886 -- There are a couple of subtleties of the test for applying
9887 -- the check that are worth noting. First, we only apply it
9888 -- when the levels of the subprogram and access type are the
9889 -- same (the case where the subprogram is statically deeper
9890 -- was applied above, and the case where the type is deeper
9891 -- is always safe). Second, we want the check to apply
9892 -- within nested generic bodies and generic child unit
9893 -- bodies, but not to apply to an attribute that appears in
9894 -- the generic unit's specification. This is done by testing
9895 -- that the attribute's innermost enclosing generic body is
9896 -- not the same as the innermost generic body enclosing the
9897 -- generic unit where the subprogram is declared (we don't
9898 -- want the check to apply when the access attribute is in
9899 -- the spec and there's some other generic body enclosing
9900 -- generic). Finally, there's no point applying the check
9901 -- when within an instance, because any violations will have
9902 -- been caught by the compilation of the generic unit.
9904 -- We relax this check in Relaxed_RM_Semantics mode for
9905 -- compatibility with legacy code for use by Ada source
9906 -- code analyzers (e.g. CodePeer).
9908 elsif Attr_Id
= Attribute_Access
9909 and then not Relaxed_RM_Semantics
9910 and then not In_Instance
9911 and then Present
(Enclosing_Generic_Unit
(Entity
(P
)))
9912 and then Present
(Enclosing_Generic_Body
(N
))
9913 and then Enclosing_Generic_Body
(N
) /=
9914 Enclosing_Generic_Body
9915 (Enclosing_Generic_Unit
(Entity
(P
)))
9916 and then Subprogram_Access_Level
(Entity
(P
)) =
9917 Type_Access_Level
(Btyp
)
9918 and then Ekind
(Btyp
) /=
9919 E_Anonymous_Access_Subprogram_Type
9920 and then Ekind
(Btyp
) /=
9921 E_Anonymous_Access_Protected_Subprogram_Type
9923 -- The attribute type's ultimate ancestor must be
9924 -- declared within the same generic unit as the
9925 -- subprogram is declared. The error message is
9926 -- specialized to say "ancestor" for the case where the
9927 -- access type is not its own ancestor, since saying
9928 -- simply "access type" would be very confusing.
9930 if Enclosing_Generic_Unit
(Entity
(P
)) /=
9931 Enclosing_Generic_Unit
(Root_Type
(Btyp
))
9934 ("''Access attribute not allowed in generic body",
9937 if Root_Type
(Btyp
) = Btyp
then
9940 "access type & is declared outside " &
9941 "generic unit (RM 3.10.2(32))", N
, Btyp
);
9944 ("\because ancestor of " &
9945 "access type & is declared outside " &
9946 "generic unit (RM 3.10.2(32))", N
, Btyp
);
9950 ("\move ''Access to private part, or " &
9951 "(Ada 2005) use anonymous access type instead of &",
9954 -- If the ultimate ancestor of the attribute's type is
9955 -- a formal type, then the attribute is illegal because
9956 -- the actual type might be declared at a higher level.
9957 -- The error message is specialized to say "ancestor"
9958 -- for the case where the access type is not its own
9959 -- ancestor, since saying simply "access type" would be
9962 elsif Is_Generic_Type
(Root_Type
(Btyp
)) then
9963 if Root_Type
(Btyp
) = Btyp
then
9965 ("access type must not be a generic formal type",
9969 ("ancestor access type must not be a generic " &
9976 -- If this is a renaming, an inherited operation, or a
9977 -- subprogram instance, use the original entity. This may make
9978 -- the node type-inconsistent, so this transformation can only
9979 -- be done if the node will not be reanalyzed. In particular,
9980 -- if it is within a default expression, the transformation
9981 -- must be delayed until the default subprogram is created for
9982 -- it, when the enclosing subprogram is frozen.
9984 if Is_Entity_Name
(P
)
9985 and then Is_Overloadable
(Entity
(P
))
9986 and then Present
(Alias
(Entity
(P
)))
9987 and then Expander_Active
9990 New_Occurrence_Of
(Alias
(Entity
(P
)), Sloc
(P
)));
9993 elsif Nkind
(P
) = N_Selected_Component
9994 and then Is_Overloadable
(Entity
(Selector_Name
(P
)))
9996 -- Protected operation. If operation is overloaded, must
9997 -- disambiguate. Prefix that denotes protected object itself
9998 -- is resolved with its own type.
10000 if Attr_Id
= Attribute_Unchecked_Access
then
10001 Error_Msg_Name_1
:= Aname
;
10003 ("attribute% cannot be applied to protected operation", P
);
10006 Resolve
(Prefix
(P
));
10007 Generate_Reference
(Entity
(Selector_Name
(P
)), P
);
10009 -- Implement check implied by 3.10.2 (18.1/2) : F.all'access is
10010 -- statically illegal if F is an anonymous access to subprogram.
10012 elsif Nkind
(P
) = N_Explicit_Dereference
10013 and then Is_Entity_Name
(Prefix
(P
))
10014 and then Ekind
(Etype
(Entity
(Prefix
(P
)))) =
10015 E_Anonymous_Access_Subprogram_Type
10017 Error_Msg_N
("anonymous access to subprogram "
10018 & "has deeper accessibility than any master", P
);
10020 elsif Is_Overloaded
(P
) then
10022 -- Use the designated type of the context to disambiguate
10023 -- Note that this was not strictly conformant to Ada 95,
10024 -- but was the implementation adopted by most Ada 95 compilers.
10025 -- The use of the context type to resolve an Access attribute
10026 -- reference is now mandated in AI-235 for Ada 2005.
10029 Index
: Interp_Index
;
10033 Get_First_Interp
(P
, Index
, It
);
10034 while Present
(It
.Typ
) loop
10035 if Covers
(Designated_Type
(Typ
), It
.Typ
) then
10036 Resolve
(P
, It
.Typ
);
10040 Get_Next_Interp
(Index
, It
);
10047 -- X'Access is illegal if X denotes a constant and the access type
10048 -- is access-to-variable. Same for 'Unchecked_Access. The rule
10049 -- does not apply to 'Unrestricted_Access. If the reference is a
10050 -- default-initialized aggregate component for a self-referential
10051 -- type the reference is legal.
10053 if not (Ekind
(Btyp
) = E_Access_Subprogram_Type
10054 or else Ekind
(Btyp
) = E_Anonymous_Access_Subprogram_Type
10055 or else (Is_Record_Type
(Btyp
)
10057 Present
(Corresponding_Remote_Type
(Btyp
)))
10058 or else Ekind
(Btyp
) = E_Access_Protected_Subprogram_Type
10059 or else Ekind
(Btyp
)
10060 = E_Anonymous_Access_Protected_Subprogram_Type
10061 or else Is_Access_Constant
(Btyp
)
10062 or else Is_Variable
(P
)
10063 or else Attr_Id
= Attribute_Unrestricted_Access
)
10065 if Is_Entity_Name
(P
)
10066 and then Is_Type
(Entity
(P
))
10068 -- Legality of a self-reference through an access
10069 -- attribute has been verified in Analyze_Access_Attribute.
10073 elsif Comes_From_Source
(N
) then
10074 Error_Msg_F
("access-to-variable designates constant", P
);
10078 Des_Btyp
:= Designated_Type
(Btyp
);
10080 if Ada_Version
>= Ada_2005
10081 and then Is_Incomplete_Type
(Des_Btyp
)
10083 -- Ada 2005 (AI-412): If the (sub)type is a limited view of an
10084 -- imported entity, and the non-limited view is visible, make
10085 -- use of it. If it is an incomplete subtype, use the base type
10088 if From_Limited_With
(Des_Btyp
)
10089 and then Present
(Non_Limited_View
(Des_Btyp
))
10091 Des_Btyp
:= Non_Limited_View
(Des_Btyp
);
10093 elsif Ekind
(Des_Btyp
) = E_Incomplete_Subtype
then
10094 Des_Btyp
:= Etype
(Des_Btyp
);
10098 if (Attr_Id
= Attribute_Access
10100 Attr_Id
= Attribute_Unchecked_Access
)
10101 and then (Ekind
(Btyp
) = E_General_Access_Type
10102 or else Ekind
(Btyp
) = E_Anonymous_Access_Type
)
10104 -- Ada 2005 (AI-230): Check the accessibility of anonymous
10105 -- access types for stand-alone objects, record and array
10106 -- components, and return objects. For a component definition
10107 -- the level is the same of the enclosing composite type.
10109 if Ada_Version
>= Ada_2005
10110 and then (Is_Local_Anonymous_Access
(Btyp
)
10112 -- Handle cases where Btyp is the anonymous access
10113 -- type of an Ada 2012 stand-alone object.
10115 or else Nkind
(Associated_Node_For_Itype
(Btyp
)) =
10116 N_Object_Declaration
)
10118 Object_Access_Level
(P
) > Deepest_Type_Access_Level
(Btyp
)
10119 and then Attr_Id
= Attribute_Access
10121 -- In an instance, this is a runtime check, but one we know
10122 -- will fail, so generate an appropriate warning. As usual,
10123 -- this kind of warning is an error in SPARK mode.
10125 if In_Instance_Body
then
10126 Error_Msg_Warn
:= SPARK_Mode
/= On
;
10128 ("non-local pointer cannot point to local object<<", P
);
10129 Error_Msg_F
("\Program_Error [<<", P
);
10132 Make_Raise_Program_Error
(Loc
,
10133 Reason
=> PE_Accessibility_Check_Failed
));
10134 Set_Etype
(N
, Typ
);
10138 ("non-local pointer cannot point to local object", P
);
10142 if Is_Dependent_Component_Of_Mutable_Object
(P
) then
10144 ("illegal attribute for discriminant-dependent component",
10148 -- Check static matching rule of 3.10.2(27). Nominal subtype
10149 -- of the prefix must statically match the designated type.
10151 Nom_Subt
:= Etype
(P
);
10153 if Is_Constr_Subt_For_U_Nominal
(Nom_Subt
) then
10154 Nom_Subt
:= Base_Type
(Nom_Subt
);
10157 if Is_Tagged_Type
(Designated_Type
(Typ
)) then
10159 -- If the attribute is in the context of an access
10160 -- parameter, then the prefix is allowed to be of the
10161 -- class-wide type (by AI-127).
10163 if Ekind
(Typ
) = E_Anonymous_Access_Type
then
10164 if not Covers
(Designated_Type
(Typ
), Nom_Subt
)
10165 and then not Covers
(Nom_Subt
, Designated_Type
(Typ
))
10171 Desig
:= Designated_Type
(Typ
);
10173 if Is_Class_Wide_Type
(Desig
) then
10174 Desig
:= Etype
(Desig
);
10177 if Is_Anonymous_Tagged_Base
(Nom_Subt
, Desig
) then
10182 ("type of prefix: & not compatible",
10185 ("\with &, the expected designated type",
10186 P
, Designated_Type
(Typ
));
10191 elsif not Covers
(Designated_Type
(Typ
), Nom_Subt
)
10193 (not Is_Class_Wide_Type
(Designated_Type
(Typ
))
10194 and then Is_Class_Wide_Type
(Nom_Subt
))
10197 ("type of prefix: & is not covered", P
, Nom_Subt
);
10199 ("\by &, the expected designated type" &
10200 " (RM 3.10.2 (27))", P
, Designated_Type
(Typ
));
10203 if Is_Class_Wide_Type
(Designated_Type
(Typ
))
10204 and then Has_Discriminants
(Etype
(Designated_Type
(Typ
)))
10205 and then Is_Constrained
(Etype
(Designated_Type
(Typ
)))
10206 and then Designated_Type
(Typ
) /= Nom_Subt
10208 Apply_Discriminant_Check
10209 (N
, Etype
(Designated_Type
(Typ
)));
10212 -- Ada 2005 (AI-363): Require static matching when designated
10213 -- type has discriminants and a constrained partial view, since
10214 -- in general objects of such types are mutable, so we can't
10215 -- allow the access value to designate a constrained object
10216 -- (because access values must be assumed to designate mutable
10217 -- objects when designated type does not impose a constraint).
10219 elsif Subtypes_Statically_Match
(Des_Btyp
, Nom_Subt
) then
10222 elsif Has_Discriminants
(Designated_Type
(Typ
))
10223 and then not Is_Constrained
(Des_Btyp
)
10225 (Ada_Version
< Ada_2005
10227 not Object_Type_Has_Constrained_Partial_View
10228 (Typ
=> Designated_Type
(Base_Type
(Typ
)),
10229 Scop
=> Current_Scope
))
10235 ("object subtype must statically match "
10236 & "designated subtype", P
);
10238 if Is_Entity_Name
(P
)
10239 and then Is_Array_Type
(Designated_Type
(Typ
))
10242 D
: constant Node_Id
:= Declaration_Node
(Entity
(P
));
10245 ("aliased object has explicit bounds??", D
);
10247 ("\declare without bounds (and with explicit "
10248 & "initialization)??", D
);
10250 ("\for use with unconstrained access??", D
);
10255 -- Check the static accessibility rule of 3.10.2(28). Note that
10256 -- this check is not performed for the case of an anonymous
10257 -- access type, since the access attribute is always legal
10258 -- in such a context.
10260 if Attr_Id
/= Attribute_Unchecked_Access
10261 and then Ekind
(Btyp
) = E_General_Access_Type
10263 Object_Access_Level
(P
) > Deepest_Type_Access_Level
(Btyp
)
10265 Accessibility_Message
;
10270 if Ekind_In
(Btyp
, E_Access_Protected_Subprogram_Type
,
10271 E_Anonymous_Access_Protected_Subprogram_Type
)
10273 if Is_Entity_Name
(P
)
10274 and then not Is_Protected_Type
(Scope
(Entity
(P
)))
10276 Error_Msg_F
("context requires a protected subprogram", P
);
10278 -- Check accessibility of protected object against that of the
10279 -- access type, but only on user code, because the expander
10280 -- creates access references for handlers. If the context is an
10281 -- anonymous_access_to_protected, there are no accessibility
10282 -- checks either. Omit check entirely for Unrestricted_Access.
10284 elsif Object_Access_Level
(P
) > Deepest_Type_Access_Level
(Btyp
)
10285 and then Comes_From_Source
(N
)
10286 and then Ekind
(Btyp
) = E_Access_Protected_Subprogram_Type
10287 and then Attr_Id
/= Attribute_Unrestricted_Access
10289 Accessibility_Message
;
10292 -- AI05-0225: If the context is not an access to protected
10293 -- function, the prefix must be a variable, given that it may
10294 -- be used subsequently in a protected call.
10296 elsif Nkind
(P
) = N_Selected_Component
10297 and then not Is_Variable
(Prefix
(P
))
10298 and then Ekind
(Entity
(Selector_Name
(P
))) /= E_Function
10301 ("target object of access to protected procedure "
10302 & "must be variable", N
);
10304 elsif Is_Entity_Name
(P
) then
10305 Check_Internal_Protected_Use
(N
, Entity
(P
));
10308 elsif Ekind_In
(Btyp
, E_Access_Subprogram_Type
,
10309 E_Anonymous_Access_Subprogram_Type
)
10310 and then Ekind
(Etype
(N
)) = E_Access_Protected_Subprogram_Type
10312 Error_Msg_F
("context requires a non-protected subprogram", P
);
10315 -- The context cannot be a pool-specific type, but this is a
10316 -- legality rule, not a resolution rule, so it must be checked
10317 -- separately, after possibly disambiguation (see AI-245).
10319 if Ekind
(Btyp
) = E_Access_Type
10320 and then Attr_Id
/= Attribute_Unrestricted_Access
10322 Wrong_Type
(N
, Typ
);
10325 -- The context may be a constrained access type (however ill-
10326 -- advised such subtypes might be) so in order to generate a
10327 -- constraint check when needed set the type of the attribute
10328 -- reference to the base type of the context.
10330 Set_Etype
(N
, Btyp
);
10332 -- Check for incorrect atomic/volatile reference (RM C.6(12))
10334 if Attr_Id
/= Attribute_Unrestricted_Access
then
10335 if Is_Atomic_Object
(P
)
10336 and then not Is_Atomic
(Designated_Type
(Typ
))
10339 ("access to atomic object cannot yield access-to-" &
10340 "non-atomic type", P
);
10342 elsif Is_Volatile_Object
(P
)
10343 and then not Is_Volatile
(Designated_Type
(Typ
))
10346 ("access to volatile object cannot yield access-to-" &
10347 "non-volatile type", P
);
10351 if Is_Entity_Name
(P
) then
10352 Set_Address_Taken
(Entity
(P
));
10354 end Access_Attribute
;
10360 -- Deal with resolving the type for Address attribute, overloading
10361 -- is not permitted here, since there is no context to resolve it.
10363 when Attribute_Address | Attribute_Code_Address
=>
10364 Address_Attribute
: begin
10366 -- To be safe, assume that if the address of a variable is taken,
10367 -- it may be modified via this address, so note modification.
10369 if Is_Variable
(P
) then
10370 Note_Possible_Modification
(P
, Sure
=> False);
10373 if Nkind
(P
) in N_Subexpr
10374 and then Is_Overloaded
(P
)
10376 Get_First_Interp
(P
, Index
, It
);
10377 Get_Next_Interp
(Index
, It
);
10379 if Present
(It
.Nam
) then
10380 Error_Msg_Name_1
:= Aname
;
10382 ("prefix of % attribute cannot be overloaded", P
);
10386 if not Is_Entity_Name
(P
)
10387 or else not Is_Overloadable
(Entity
(P
))
10389 if not Is_Task_Type
(Etype
(P
))
10390 or else Nkind
(P
) = N_Explicit_Dereference
10396 -- If this is the name of a derived subprogram, or that of a
10397 -- generic actual, the address is that of the original entity.
10399 if Is_Entity_Name
(P
)
10400 and then Is_Overloadable
(Entity
(P
))
10401 and then Present
(Alias
(Entity
(P
)))
10404 New_Occurrence_Of
(Alias
(Entity
(P
)), Sloc
(P
)));
10407 if Is_Entity_Name
(P
) then
10408 Set_Address_Taken
(Entity
(P
));
10411 if Nkind
(P
) = N_Slice
then
10413 -- Arr (X .. Y)'address is identical to Arr (X)'address,
10414 -- even if the array is packed and the slice itself is not
10415 -- addressable. Transform the prefix into an indexed component.
10417 -- Note that the transformation is safe only if we know that
10418 -- the slice is non-null. That is because a null slice can have
10419 -- an out of bounds index value.
10421 -- Right now, gigi blows up if given 'Address on a slice as a
10422 -- result of some incorrect freeze nodes generated by the front
10423 -- end, and this covers up that bug in one case, but the bug is
10424 -- likely still there in the cases not handled by this code ???
10426 -- It's not clear what 'Address *should* return for a null
10427 -- slice with out of bounds indexes, this might be worth an ARG
10430 -- One approach would be to do a length check unconditionally,
10431 -- and then do the transformation below unconditionally, but
10432 -- analyze with checks off, avoiding the problem of the out of
10433 -- bounds index. This approach would interpret the address of
10434 -- an out of bounds null slice as being the address where the
10435 -- array element would be if there was one, which is probably
10436 -- as reasonable an interpretation as any ???
10439 Loc
: constant Source_Ptr
:= Sloc
(P
);
10440 D
: constant Node_Id
:= Discrete_Range
(P
);
10444 if Is_Entity_Name
(D
)
10447 (Type_Low_Bound
(Entity
(D
)),
10448 Type_High_Bound
(Entity
(D
)))
10451 Make_Attribute_Reference
(Loc
,
10452 Prefix
=> (New_Occurrence_Of
(Entity
(D
), Loc
)),
10453 Attribute_Name
=> Name_First
);
10455 elsif Nkind
(D
) = N_Range
10456 and then Not_Null_Range
(Low_Bound
(D
), High_Bound
(D
))
10458 Lo
:= Low_Bound
(D
);
10464 if Present
(Lo
) then
10466 Make_Indexed_Component
(Loc
,
10467 Prefix
=> Relocate_Node
(Prefix
(P
)),
10468 Expressions
=> New_List
(Lo
)));
10470 Analyze_And_Resolve
(P
);
10474 end Address_Attribute
;
10480 -- Prefix of the AST_Entry attribute is an entry name which must
10481 -- not be resolved, since this is definitely not an entry call.
10483 when Attribute_AST_Entry
=>
10490 -- Prefix of Body_Version attribute can be a subprogram name which
10491 -- must not be resolved, since this is not a call.
10493 when Attribute_Body_Version
=>
10500 -- Prefix of Caller attribute is an entry name which must not
10501 -- be resolved, since this is definitely not an entry call.
10503 when Attribute_Caller
=>
10510 -- Shares processing with Address attribute
10516 -- If the prefix of the Count attribute is an entry name it must not
10517 -- be resolved, since this is definitely not an entry call. However,
10518 -- if it is an element of an entry family, the index itself may
10519 -- have to be resolved because it can be a general expression.
10521 when Attribute_Count
=>
10522 if Nkind
(P
) = N_Indexed_Component
10523 and then Is_Entity_Name
(Prefix
(P
))
10526 Indx
: constant Node_Id
:= First
(Expressions
(P
));
10527 Fam
: constant Entity_Id
:= Entity
(Prefix
(P
));
10529 Resolve
(Indx
, Entry_Index_Type
(Fam
));
10530 Apply_Range_Check
(Indx
, Entry_Index_Type
(Fam
));
10538 -- Prefix of the Elaborated attribute is a subprogram name which
10539 -- must not be resolved, since this is definitely not a call. Note
10540 -- that it is a library unit, so it cannot be overloaded here.
10542 when Attribute_Elaborated
=>
10549 -- Prefix of Enabled attribute is a check name, which must be treated
10550 -- specially and not touched by Resolve.
10552 when Attribute_Enabled
=>
10559 -- Do not resolve the prefix of Loop_Entry, instead wait until the
10560 -- attribute has been expanded (see Expand_Loop_Entry_Attributes).
10561 -- The delay ensures that any generated checks or temporaries are
10562 -- inserted before the relocated prefix.
10564 when Attribute_Loop_Entry
=>
10567 --------------------
10568 -- Mechanism_Code --
10569 --------------------
10571 -- Prefix of the Mechanism_Code attribute is a function name
10572 -- which must not be resolved. Should we check for overloaded ???
10574 when Attribute_Mechanism_Code
=>
10581 -- Most processing is done in sem_dist, after determining the
10582 -- context type. Node is rewritten as a conversion to a runtime call.
10584 when Attribute_Partition_ID
=>
10585 Process_Partition_Id
(N
);
10592 when Attribute_Pool_Address
=>
10599 -- We replace the Range attribute node with a range expression whose
10600 -- bounds are the 'First and 'Last attributes applied to the same
10601 -- prefix. The reason that we do this transformation here instead of
10602 -- in the expander is that it simplifies other parts of the semantic
10603 -- analysis which assume that the Range has been replaced; thus it
10604 -- must be done even when in semantic-only mode (note that the RM
10605 -- specifically mentions this equivalence, we take care that the
10606 -- prefix is only evaluated once).
10608 when Attribute_Range
=> Range_Attribute
:
10615 if not Is_Entity_Name
(P
)
10616 or else not Is_Type
(Entity
(P
))
10621 Dims
:= Expressions
(N
);
10624 Make_Attribute_Reference
(Loc
,
10626 Duplicate_Subexpr
(P
, Name_Req
=> True),
10627 Attribute_Name
=> Name_Last
,
10628 Expressions
=> Dims
);
10631 Make_Attribute_Reference
(Loc
,
10633 Attribute_Name
=> Name_First
,
10634 Expressions
=> (Dims
));
10636 -- Do not share the dimension indicator, if present. Even
10637 -- though it is a static constant, its source location
10638 -- may be modified when printing expanded code and node
10639 -- sharing will lead to chaos in Sprint.
10641 if Present
(Dims
) then
10642 Set_Expressions
(LB
,
10643 New_List
(New_Copy_Tree
(First
(Dims
))));
10646 -- If the original was marked as Must_Not_Freeze (see code
10647 -- in Sem_Ch3.Make_Index), then make sure the rewriting
10648 -- does not freeze either.
10650 if Must_Not_Freeze
(N
) then
10651 Set_Must_Not_Freeze
(HB
);
10652 Set_Must_Not_Freeze
(LB
);
10653 Set_Must_Not_Freeze
(Prefix
(HB
));
10654 Set_Must_Not_Freeze
(Prefix
(LB
));
10657 if Raises_Constraint_Error
(Prefix
(N
)) then
10659 -- Preserve Sloc of prefix in the new bounds, so that
10660 -- the posted warning can be removed if we are within
10661 -- unreachable code.
10663 Set_Sloc
(LB
, Sloc
(Prefix
(N
)));
10664 Set_Sloc
(HB
, Sloc
(Prefix
(N
)));
10667 Rewrite
(N
, Make_Range
(Loc
, LB
, HB
));
10668 Analyze_And_Resolve
(N
, Typ
);
10670 -- Ensure that the expanded range does not have side effects
10672 Force_Evaluation
(LB
);
10673 Force_Evaluation
(HB
);
10675 -- Normally after resolving attribute nodes, Eval_Attribute
10676 -- is called to do any possible static evaluation of the node.
10677 -- However, here since the Range attribute has just been
10678 -- transformed into a range expression it is no longer an
10679 -- attribute node and therefore the call needs to be avoided
10680 -- and is accomplished by simply returning from the procedure.
10683 end Range_Attribute
;
10689 -- We will only come here during the prescan of a spec expression
10690 -- containing a Result attribute. In that case the proper Etype has
10691 -- already been set, and nothing more needs to be done here.
10693 when Attribute_Result
=>
10700 -- Prefix must not be resolved in this case, since it is not a
10701 -- real entity reference. No action of any kind is require.
10703 when Attribute_UET_Address
=>
10706 ----------------------
10707 -- Unchecked_Access --
10708 ----------------------
10710 -- Processing is shared with Access
10712 -------------------------
10713 -- Unrestricted_Access --
10714 -------------------------
10716 -- Processing is shared with Access
10722 -- Resolve aggregate components in component associations
10724 when Attribute_Update
=>
10726 Aggr
: constant Node_Id
:= First
(Expressions
(N
));
10727 Typ
: constant Entity_Id
:= Etype
(Prefix
(N
));
10732 -- Set the Etype of the aggregate to that of the prefix, even
10733 -- though the aggregate may not be a proper representation of a
10734 -- value of the type (missing or duplicated associations, etc.)
10735 -- Complete resolution of the prefix. Note that in Ada 2012 it
10736 -- can be a qualified expression that is e.g. an aggregate.
10738 Set_Etype
(Aggr
, Typ
);
10739 Resolve
(Prefix
(N
), Typ
);
10741 -- For an array type, resolve expressions with the component
10742 -- type of the array.
10744 if Is_Array_Type
(Typ
) then
10745 Assoc
:= First
(Component_Associations
(Aggr
));
10746 while Present
(Assoc
) loop
10747 Resolve
(Expression
(Assoc
), Component_Type
(Typ
));
10751 -- For a record type, use type of each component, which is
10752 -- recorded during analysis.
10755 Assoc
:= First
(Component_Associations
(Aggr
));
10756 while Present
(Assoc
) loop
10757 Comp
:= First
(Choices
(Assoc
));
10758 if Nkind
(Comp
) /= N_Others_Choice
10759 and then not Error_Posted
(Comp
)
10761 Resolve
(Expression
(Assoc
), Etype
(Entity
(Comp
)));
10768 -- Premature return requires comment ???
10776 -- Apply range check. Note that we did not do this during the
10777 -- analysis phase, since we wanted Eval_Attribute to have a
10778 -- chance at finding an illegal out of range value.
10780 when Attribute_Val
=>
10782 -- Note that we do our own Eval_Attribute call here rather than
10783 -- use the common one, because we need to do processing after
10784 -- the call, as per above comment.
10786 Eval_Attribute
(N
);
10788 -- Eval_Attribute may replace the node with a raise CE, or
10789 -- fold it to a constant. Obviously we only apply a scalar
10790 -- range check if this did not happen.
10792 if Nkind
(N
) = N_Attribute_Reference
10793 and then Attribute_Name
(N
) = Name_Val
10795 Apply_Scalar_Range_Check
(First
(Expressions
(N
)), Btyp
);
10804 -- Prefix of Version attribute can be a subprogram name which
10805 -- must not be resolved, since this is not a call.
10807 when Attribute_Version
=>
10810 ----------------------
10811 -- Other Attributes --
10812 ----------------------
10814 -- For other attributes, resolve prefix unless it is a type. If
10815 -- the attribute reference itself is a type name ('Base and 'Class)
10816 -- then this is only legal within a task or protected record.
10819 if not Is_Entity_Name
(P
) or else not Is_Type
(Entity
(P
)) then
10823 -- If the attribute reference itself is a type name ('Base,
10824 -- 'Class) then this is only legal within a task or protected
10825 -- record. What is this all about ???
10827 if Is_Entity_Name
(N
) and then Is_Type
(Entity
(N
)) then
10828 if Is_Concurrent_Type
(Entity
(N
))
10829 and then In_Open_Scopes
(Entity
(P
))
10834 ("invalid use of subtype name in expression or call", N
);
10838 -- For attributes whose argument may be a string, complete
10839 -- resolution of argument now. This avoids premature expansion
10840 -- (and the creation of transient scopes) before the attribute
10841 -- reference is resolved.
10844 when Attribute_Value
=>
10845 Resolve
(First
(Expressions
(N
)), Standard_String
);
10847 when Attribute_Wide_Value
=>
10848 Resolve
(First
(Expressions
(N
)), Standard_Wide_String
);
10850 when Attribute_Wide_Wide_Value
=>
10851 Resolve
(First
(Expressions
(N
)), Standard_Wide_Wide_String
);
10853 when others => null;
10856 -- If the prefix of the attribute is a class-wide type then it
10857 -- will be expanded into a dispatching call to a predefined
10858 -- primitive. Therefore we must check for potential violation
10859 -- of such restriction.
10861 if Is_Class_Wide_Type
(Etype
(P
)) then
10862 Check_Restriction
(No_Dispatching_Calls
, N
);
10866 -- Normally the Freezing is done by Resolve but sometimes the Prefix
10867 -- is not resolved, in which case the freezing must be done now.
10869 Freeze_Expression
(P
);
10871 -- Finally perform static evaluation on the attribute reference
10873 Analyze_Dimension
(N
);
10874 Eval_Attribute
(N
);
10875 end Resolve_Attribute
;
10877 ------------------------
10878 -- Set_Boolean_Result --
10879 ------------------------
10881 procedure Set_Boolean_Result
(N
: Node_Id
; B
: Boolean) is
10882 Loc
: constant Source_Ptr
:= Sloc
(N
);
10886 Rewrite
(N
, New_Occurrence_Of
(Standard_True
, Loc
));
10888 Rewrite
(N
, New_Occurrence_Of
(Standard_False
, Loc
));
10891 Set_Is_Static_Expression
(N
);
10892 end Set_Boolean_Result
;
10894 --------------------------------
10895 -- Stream_Attribute_Available --
10896 --------------------------------
10898 function Stream_Attribute_Available
10900 Nam
: TSS_Name_Type
;
10901 Partial_View
: Node_Id
:= Empty
) return Boolean
10903 Etyp
: Entity_Id
:= Typ
;
10905 -- Start of processing for Stream_Attribute_Available
10908 -- We need some comments in this body ???
10910 if Has_Stream_Attribute_Definition
(Typ
, Nam
) then
10914 if Is_Class_Wide_Type
(Typ
) then
10915 return not Is_Limited_Type
(Typ
)
10916 or else Stream_Attribute_Available
(Etype
(Typ
), Nam
);
10919 if Nam
= TSS_Stream_Input
10920 and then Is_Abstract_Type
(Typ
)
10921 and then not Is_Class_Wide_Type
(Typ
)
10926 if not (Is_Limited_Type
(Typ
)
10927 or else (Present
(Partial_View
)
10928 and then Is_Limited_Type
(Partial_View
)))
10933 -- In Ada 2005, Input can invoke Read, and Output can invoke Write
10935 if Nam
= TSS_Stream_Input
10936 and then Ada_Version
>= Ada_2005
10937 and then Stream_Attribute_Available
(Etyp
, TSS_Stream_Read
)
10941 elsif Nam
= TSS_Stream_Output
10942 and then Ada_Version
>= Ada_2005
10943 and then Stream_Attribute_Available
(Etyp
, TSS_Stream_Write
)
10948 -- Case of Read and Write: check for attribute definition clause that
10949 -- applies to an ancestor type.
10951 while Etype
(Etyp
) /= Etyp
loop
10952 Etyp
:= Etype
(Etyp
);
10954 if Has_Stream_Attribute_Definition
(Etyp
, Nam
) then
10959 if Ada_Version
< Ada_2005
then
10961 -- In Ada 95 mode, also consider a non-visible definition
10964 Btyp
: constant Entity_Id
:= Implementation_Base_Type
(Typ
);
10967 and then Stream_Attribute_Available
10968 (Btyp
, Nam
, Partial_View
=> Typ
);
10973 end Stream_Attribute_Available
;