1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2017, 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 Atree
; use Atree
;
27 with Checks
; use Checks
;
28 with Debug
; use Debug
;
29 with Debug_A
; use Debug_A
;
30 with Einfo
; use Einfo
;
31 with Errout
; use Errout
;
32 with Expander
; use Expander
;
33 with Exp_Disp
; use Exp_Disp
;
34 with Exp_Ch6
; use Exp_Ch6
;
35 with Exp_Ch7
; use Exp_Ch7
;
36 with Exp_Tss
; use Exp_Tss
;
37 with Exp_Util
; use Exp_Util
;
38 with Freeze
; use Freeze
;
39 with Ghost
; use Ghost
;
40 with Inline
; use Inline
;
41 with Itypes
; use Itypes
;
43 with Lib
.Xref
; use Lib
.Xref
;
44 with Namet
; use Namet
;
45 with Nmake
; use Nmake
;
46 with Nlists
; use Nlists
;
48 with Output
; use Output
;
49 with Par_SCO
; use Par_SCO
;
50 with Restrict
; use Restrict
;
51 with Rident
; use Rident
;
52 with Rtsfind
; use Rtsfind
;
54 with Sem_Aux
; use Sem_Aux
;
55 with Sem_Aggr
; use Sem_Aggr
;
56 with Sem_Attr
; use Sem_Attr
;
57 with Sem_Cat
; use Sem_Cat
;
58 with Sem_Ch4
; use Sem_Ch4
;
59 with Sem_Ch3
; use Sem_Ch3
;
60 with Sem_Ch6
; use Sem_Ch6
;
61 with Sem_Ch8
; use Sem_Ch8
;
62 with Sem_Ch13
; use Sem_Ch13
;
63 with Sem_Dim
; use Sem_Dim
;
64 with Sem_Disp
; use Sem_Disp
;
65 with Sem_Dist
; use Sem_Dist
;
66 with Sem_Elab
; use Sem_Elab
;
67 with Sem_Elim
; use Sem_Elim
;
68 with Sem_Eval
; use Sem_Eval
;
69 with Sem_Intr
; use Sem_Intr
;
70 with Sem_Util
; use Sem_Util
;
71 with Targparm
; use Targparm
;
72 with Sem_Type
; use Sem_Type
;
73 with Sem_Warn
; use Sem_Warn
;
74 with Sinfo
; use Sinfo
;
75 with Sinfo
.CN
; use Sinfo
.CN
;
76 with Snames
; use Snames
;
77 with Stand
; use Stand
;
78 with Stringt
; use Stringt
;
79 with Style
; use Style
;
80 with Tbuild
; use Tbuild
;
81 with Uintp
; use Uintp
;
82 with Urealp
; use Urealp
;
84 package body Sem_Res
is
86 -----------------------
87 -- Local Subprograms --
88 -----------------------
90 -- Second pass (top-down) type checking and overload resolution procedures
91 -- Typ is the type required by context. These procedures propagate the
92 -- type information recursively to the descendants of N. If the node is not
93 -- overloaded, its Etype is established in the first pass. If overloaded,
94 -- the Resolve routines set the correct type. For arithmetic operators, the
95 -- Etype is the base type of the context.
97 -- Note that Resolve_Attribute is separated off in Sem_Attr
99 procedure Check_Discriminant_Use
(N
: Node_Id
);
100 -- Enforce the restrictions on the use of discriminants when constraining
101 -- a component of a discriminated type (record or concurrent type).
103 procedure Check_For_Visible_Operator
(N
: Node_Id
; T
: Entity_Id
);
104 -- Given a node for an operator associated with type T, check that the
105 -- operator is visible. Operators all of whose operands are universal must
106 -- be checked for visibility during resolution because their type is not
107 -- determinable based on their operands.
109 procedure Check_Fully_Declared_Prefix
112 -- Check that the type of the prefix of a dereference is not incomplete
114 function Check_Infinite_Recursion
(N
: Node_Id
) return Boolean;
115 -- Given a call node, N, which is known to occur immediately within the
116 -- subprogram being called, determines whether it is a detectable case of
117 -- an infinite recursion, and if so, outputs appropriate messages. Returns
118 -- True if an infinite recursion is detected, and False otherwise.
120 procedure Check_Initialization_Call
(N
: Entity_Id
; Nam
: Entity_Id
);
121 -- If the type of the object being initialized uses the secondary stack
122 -- directly or indirectly, create a transient scope for the call to the
123 -- init proc. This is because we do not create transient scopes for the
124 -- initialization of individual components within the init proc itself.
125 -- Could be optimized away perhaps?
127 procedure Check_No_Direct_Boolean_Operators
(N
: Node_Id
);
128 -- N is the node for a logical operator. If the operator is predefined, and
129 -- the root type of the operands is Standard.Boolean, then a check is made
130 -- for restriction No_Direct_Boolean_Operators. This procedure also handles
131 -- the style check for Style_Check_Boolean_And_Or.
133 function Is_Atomic_Ref_With_Address
(N
: Node_Id
) return Boolean;
134 -- N is either an indexed component or a selected component. This function
135 -- returns true if the prefix refers to an object that has an address
136 -- clause (the case in which we may want to issue a warning).
138 function Is_Definite_Access_Type
(E
: Entity_Id
) return Boolean;
139 -- Determine whether E is an access type declared by an access declaration,
140 -- and not an (anonymous) allocator type.
142 function Is_Predefined_Op
(Nam
: Entity_Id
) return Boolean;
143 -- Utility to check whether the entity for an operator is a predefined
144 -- operator, in which case the expression is left as an operator in the
145 -- tree (else it is rewritten into a call). An instance of an intrinsic
146 -- conversion operation may be given an operator name, but is not treated
147 -- like an operator. Note that an operator that is an imported back-end
148 -- builtin has convention Intrinsic, but is expected to be rewritten into
149 -- a call, so such an operator is not treated as predefined by this
152 procedure Replace_Actual_Discriminants
(N
: Node_Id
; Default
: Node_Id
);
153 -- If a default expression in entry call N depends on the discriminants
154 -- of the task, it must be replaced with a reference to the discriminant
155 -- of the task being called.
157 procedure Resolve_Op_Concat_Arg
162 -- Internal procedure for Resolve_Op_Concat to resolve one operand of
163 -- concatenation operator. The operand is either of the array type or of
164 -- the component type. If the operand is an aggregate, and the component
165 -- type is composite, this is ambiguous if component type has aggregates.
167 procedure Resolve_Op_Concat_First
(N
: Node_Id
; Typ
: Entity_Id
);
168 -- Does the first part of the work of Resolve_Op_Concat
170 procedure Resolve_Op_Concat_Rest
(N
: Node_Id
; Typ
: Entity_Id
);
171 -- Does the "rest" of the work of Resolve_Op_Concat, after the left operand
172 -- has been resolved. See Resolve_Op_Concat for details.
174 procedure Resolve_Allocator
(N
: Node_Id
; Typ
: Entity_Id
);
175 procedure Resolve_Arithmetic_Op
(N
: Node_Id
; Typ
: Entity_Id
);
176 procedure Resolve_Call
(N
: Node_Id
; Typ
: Entity_Id
);
177 procedure Resolve_Case_Expression
(N
: Node_Id
; Typ
: Entity_Id
);
178 procedure Resolve_Character_Literal
(N
: Node_Id
; Typ
: Entity_Id
);
179 procedure Resolve_Comparison_Op
(N
: Node_Id
; Typ
: Entity_Id
);
180 procedure Resolve_Entity_Name
(N
: Node_Id
; Typ
: Entity_Id
);
181 procedure Resolve_Equality_Op
(N
: Node_Id
; Typ
: Entity_Id
);
182 procedure Resolve_Explicit_Dereference
(N
: Node_Id
; Typ
: Entity_Id
);
183 procedure Resolve_Expression_With_Actions
(N
: Node_Id
; Typ
: Entity_Id
);
184 procedure Resolve_If_Expression
(N
: Node_Id
; Typ
: Entity_Id
);
185 procedure Resolve_Generalized_Indexing
(N
: Node_Id
; Typ
: Entity_Id
);
186 procedure Resolve_Indexed_Component
(N
: Node_Id
; Typ
: Entity_Id
);
187 procedure Resolve_Integer_Literal
(N
: Node_Id
; Typ
: Entity_Id
);
188 procedure Resolve_Logical_Op
(N
: Node_Id
; Typ
: Entity_Id
);
189 procedure Resolve_Membership_Op
(N
: Node_Id
; Typ
: Entity_Id
);
190 procedure Resolve_Null
(N
: Node_Id
; Typ
: Entity_Id
);
191 procedure Resolve_Operator_Symbol
(N
: Node_Id
; Typ
: Entity_Id
);
192 procedure Resolve_Op_Concat
(N
: Node_Id
; Typ
: Entity_Id
);
193 procedure Resolve_Op_Expon
(N
: Node_Id
; Typ
: Entity_Id
);
194 procedure Resolve_Op_Not
(N
: Node_Id
; Typ
: Entity_Id
);
195 procedure Resolve_Qualified_Expression
(N
: Node_Id
; Typ
: Entity_Id
);
196 procedure Resolve_Raise_Expression
(N
: Node_Id
; Typ
: Entity_Id
);
197 procedure Resolve_Range
(N
: Node_Id
; Typ
: Entity_Id
);
198 procedure Resolve_Real_Literal
(N
: Node_Id
; Typ
: Entity_Id
);
199 procedure Resolve_Reference
(N
: Node_Id
; Typ
: Entity_Id
);
200 procedure Resolve_Selected_Component
(N
: Node_Id
; Typ
: Entity_Id
);
201 procedure Resolve_Shift
(N
: Node_Id
; Typ
: Entity_Id
);
202 procedure Resolve_Short_Circuit
(N
: Node_Id
; Typ
: Entity_Id
);
203 procedure Resolve_Slice
(N
: Node_Id
; Typ
: Entity_Id
);
204 procedure Resolve_String_Literal
(N
: Node_Id
; Typ
: Entity_Id
);
205 procedure Resolve_Target_Name
(N
: Node_Id
; Typ
: Entity_Id
);
206 procedure Resolve_Type_Conversion
(N
: Node_Id
; Typ
: Entity_Id
);
207 procedure Resolve_Unary_Op
(N
: Node_Id
; Typ
: Entity_Id
);
208 procedure Resolve_Unchecked_Expression
(N
: Node_Id
; Typ
: Entity_Id
);
209 procedure Resolve_Unchecked_Type_Conversion
(N
: Node_Id
; Typ
: Entity_Id
);
211 function Operator_Kind
213 Is_Binary
: Boolean) return Node_Kind
;
214 -- Utility to map the name of an operator into the corresponding Node. Used
215 -- by other node rewriting procedures.
217 procedure Resolve_Actuals
(N
: Node_Id
; Nam
: Entity_Id
);
218 -- Resolve actuals of call, and add default expressions for missing ones.
219 -- N is the Node_Id for the subprogram call, and Nam is the entity of the
220 -- called subprogram.
222 procedure Resolve_Entry_Call
(N
: Node_Id
; Typ
: Entity_Id
);
223 -- Called from Resolve_Call, when the prefix denotes an entry or element
224 -- of entry family. Actuals are resolved as for subprograms, and the node
225 -- is rebuilt as an entry call. Also called for protected operations. Typ
226 -- is the context type, which is used when the operation is a protected
227 -- function with no arguments, and the return value is indexed.
229 procedure Resolve_Intrinsic_Operator
(N
: Node_Id
; Typ
: Entity_Id
);
230 -- A call to a user-defined intrinsic operator is rewritten as a call to
231 -- the corresponding predefined operator, with suitable conversions. Note
232 -- that this applies only for intrinsic operators that denote predefined
233 -- operators, not ones that are intrinsic imports of back-end builtins.
235 procedure Resolve_Intrinsic_Unary_Operator
(N
: Node_Id
; Typ
: Entity_Id
);
236 -- Ditto, for arithmetic unary operators
238 procedure Rewrite_Operator_As_Call
(N
: Node_Id
; Nam
: Entity_Id
);
239 -- If an operator node resolves to a call to a user-defined operator,
240 -- rewrite the node as a function call.
242 procedure Make_Call_Into_Operator
246 -- Inverse transformation: if an operator is given in functional notation,
247 -- then after resolving the node, transform into an operator node, so that
248 -- operands are resolved properly. Recall that predefined operators do not
249 -- have a full signature and special resolution rules apply.
251 procedure Rewrite_Renamed_Operator
255 -- An operator can rename another, e.g. in an instantiation. In that
256 -- case, the proper operator node must be constructed and resolved.
258 procedure Set_String_Literal_Subtype
(N
: Node_Id
; Typ
: Entity_Id
);
259 -- The String_Literal_Subtype is built for all strings that are not
260 -- operands of a static concatenation operation. If the argument is not
261 -- a N_String_Literal node, then the call has no effect.
263 procedure Set_Slice_Subtype
(N
: Node_Id
);
264 -- Build subtype of array type, with the range specified by the slice
266 procedure Simplify_Type_Conversion
(N
: Node_Id
);
267 -- Called after N has been resolved and evaluated, but before range checks
268 -- have been applied. Currently simplifies a combination of floating-point
269 -- to integer conversion and Rounding or Truncation attribute.
271 function Unique_Fixed_Point_Type
(N
: Node_Id
) return Entity_Id
;
272 -- A universal_fixed expression in an universal context is unambiguous if
273 -- there is only one applicable fixed point type. Determining whether there
274 -- is only one requires a search over all visible entities, and happens
275 -- only in very pathological cases (see 6115-006).
277 -------------------------
278 -- Ambiguous_Character --
279 -------------------------
281 procedure Ambiguous_Character
(C
: Node_Id
) is
285 if Nkind
(C
) = N_Character_Literal
then
286 Error_Msg_N
("ambiguous character literal", C
);
288 -- First the ones in Standard
290 Error_Msg_N
("\\possible interpretation: Character!", C
);
291 Error_Msg_N
("\\possible interpretation: Wide_Character!", C
);
293 -- Include Wide_Wide_Character in Ada 2005 mode
295 if Ada_Version
>= Ada_2005
then
296 Error_Msg_N
("\\possible interpretation: Wide_Wide_Character!", C
);
299 -- Now any other types that match
301 E
:= Current_Entity
(C
);
302 while Present
(E
) loop
303 Error_Msg_NE
("\\possible interpretation:}!", C
, Etype
(E
));
307 end Ambiguous_Character
;
309 -------------------------
310 -- Analyze_And_Resolve --
311 -------------------------
313 procedure Analyze_And_Resolve
(N
: Node_Id
) is
317 end Analyze_And_Resolve
;
319 procedure Analyze_And_Resolve
(N
: Node_Id
; Typ
: Entity_Id
) is
323 end Analyze_And_Resolve
;
325 -- Versions with check(s) suppressed
327 procedure Analyze_And_Resolve
332 Scop
: constant Entity_Id
:= Current_Scope
;
335 if Suppress
= All_Checks
then
337 Sva
: constant Suppress_Array
:= Scope_Suppress
.Suppress
;
339 Scope_Suppress
.Suppress
:= (others => True);
340 Analyze_And_Resolve
(N
, Typ
);
341 Scope_Suppress
.Suppress
:= Sva
;
346 Svg
: constant Boolean := Scope_Suppress
.Suppress
(Suppress
);
348 Scope_Suppress
.Suppress
(Suppress
) := True;
349 Analyze_And_Resolve
(N
, Typ
);
350 Scope_Suppress
.Suppress
(Suppress
) := Svg
;
354 if Current_Scope
/= Scop
355 and then Scope_Is_Transient
357 -- This can only happen if a transient scope was created for an inner
358 -- expression, which will be removed upon completion of the analysis
359 -- of an enclosing construct. The transient scope must have the
360 -- suppress status of the enclosing environment, not of this Analyze
363 Scope_Stack
.Table
(Scope_Stack
.Last
).Save_Scope_Suppress
:=
366 end Analyze_And_Resolve
;
368 procedure Analyze_And_Resolve
372 Scop
: constant Entity_Id
:= Current_Scope
;
375 if Suppress
= All_Checks
then
377 Sva
: constant Suppress_Array
:= Scope_Suppress
.Suppress
;
379 Scope_Suppress
.Suppress
:= (others => True);
380 Analyze_And_Resolve
(N
);
381 Scope_Suppress
.Suppress
:= Sva
;
386 Svg
: constant Boolean := Scope_Suppress
.Suppress
(Suppress
);
388 Scope_Suppress
.Suppress
(Suppress
) := True;
389 Analyze_And_Resolve
(N
);
390 Scope_Suppress
.Suppress
(Suppress
) := Svg
;
394 if Current_Scope
/= Scop
and then Scope_Is_Transient
then
395 Scope_Stack
.Table
(Scope_Stack
.Last
).Save_Scope_Suppress
:=
398 end Analyze_And_Resolve
;
400 ----------------------------
401 -- Check_Discriminant_Use --
402 ----------------------------
404 procedure Check_Discriminant_Use
(N
: Node_Id
) is
405 PN
: constant Node_Id
:= Parent
(N
);
406 Disc
: constant Entity_Id
:= Entity
(N
);
411 -- Any use in a spec-expression is legal
413 if In_Spec_Expression
then
416 elsif Nkind
(PN
) = N_Range
then
418 -- Discriminant cannot be used to constrain a scalar type
422 if Nkind
(P
) = N_Range_Constraint
423 and then Nkind
(Parent
(P
)) = N_Subtype_Indication
424 and then Nkind
(Parent
(Parent
(P
))) = N_Component_Definition
426 Error_Msg_N
("discriminant cannot constrain scalar type", N
);
428 elsif Nkind
(P
) = N_Index_Or_Discriminant_Constraint
then
430 -- The following check catches the unusual case where a
431 -- discriminant appears within an index constraint that is part
432 -- of a larger expression within a constraint on a component,
433 -- e.g. "C : Int range 1 .. F (new A(1 .. D))". For now we only
434 -- check case of record components, and note that a similar check
435 -- should also apply in the case of discriminant constraints
438 -- Note that the check for N_Subtype_Declaration below is to
439 -- detect the valid use of discriminants in the constraints of a
440 -- subtype declaration when this subtype declaration appears
441 -- inside the scope of a record type (which is syntactically
442 -- illegal, but which may be created as part of derived type
443 -- processing for records). See Sem_Ch3.Build_Derived_Record_Type
446 if Ekind
(Current_Scope
) = E_Record_Type
447 and then Scope
(Disc
) = Current_Scope
449 (Nkind
(Parent
(P
)) = N_Subtype_Indication
451 Nkind_In
(Parent
(Parent
(P
)), N_Component_Definition
,
452 N_Subtype_Declaration
)
453 and then Paren_Count
(N
) = 0)
456 ("discriminant must appear alone in component constraint", N
);
460 -- Detect a common error:
462 -- type R (D : Positive := 100) is record
463 -- Name : String (1 .. D);
466 -- The default value causes an object of type R to be allocated
467 -- with room for Positive'Last characters. The RM does not mandate
468 -- the allocation of the maximum size, but that is what GNAT does
469 -- so we should warn the programmer that there is a problem.
471 Check_Large
: declare
477 function Large_Storage_Type
(T
: Entity_Id
) return Boolean;
478 -- Return True if type T has a large enough range that any
479 -- array whose index type covered the whole range of the type
480 -- would likely raise Storage_Error.
482 ------------------------
483 -- Large_Storage_Type --
484 ------------------------
486 function Large_Storage_Type
(T
: Entity_Id
) return Boolean is
488 -- The type is considered large if its bounds are known at
489 -- compile time and if it requires at least as many bits as
490 -- a Positive to store the possible values.
492 return Compile_Time_Known_Value
(Type_Low_Bound
(T
))
493 and then Compile_Time_Known_Value
(Type_High_Bound
(T
))
495 Minimum_Size
(T
, Biased
=> True) >=
496 RM_Size
(Standard_Positive
);
497 end Large_Storage_Type
;
499 -- Start of processing for Check_Large
502 -- Check that the Disc has a large range
504 if not Large_Storage_Type
(Etype
(Disc
)) then
508 -- If the enclosing type is limited, we allocate only the
509 -- default value, not the maximum, and there is no need for
512 if Is_Limited_Type
(Scope
(Disc
)) then
516 -- Check that it is the high bound
518 if N
/= High_Bound
(PN
)
519 or else No
(Discriminant_Default_Value
(Disc
))
524 -- Check the array allows a large range at this bound. First
529 if Nkind
(SI
) /= N_Subtype_Indication
then
533 T
:= Entity
(Subtype_Mark
(SI
));
535 if not Is_Array_Type
(T
) then
539 -- Next, find the dimension
541 TB
:= First_Index
(T
);
542 CB
:= First
(Constraints
(P
));
544 and then Present
(TB
)
545 and then Present
(CB
)
556 -- Now, check the dimension has a large range
558 if not Large_Storage_Type
(Etype
(TB
)) then
562 -- Warn about the danger
565 ("??creation of & object may raise Storage_Error!",
574 -- Legal case is in index or discriminant constraint
576 elsif Nkind_In
(PN
, N_Index_Or_Discriminant_Constraint
,
577 N_Discriminant_Association
)
579 if Paren_Count
(N
) > 0 then
581 ("discriminant in constraint must appear alone", N
);
583 elsif Nkind
(N
) = N_Expanded_Name
584 and then Comes_From_Source
(N
)
587 ("discriminant must appear alone as a direct name", N
);
592 -- Otherwise, context is an expression. It should not be within (i.e. a
593 -- subexpression of) a constraint for a component.
598 while not Nkind_In
(P
, N_Component_Declaration
,
599 N_Subtype_Indication
,
607 -- If the discriminant is used in an expression that is a bound of a
608 -- scalar type, an Itype is created and the bounds are attached to
609 -- its range, not to the original subtype indication. Such use is of
610 -- course a double fault.
612 if (Nkind
(P
) = N_Subtype_Indication
613 and then Nkind_In
(Parent
(P
), N_Component_Definition
,
614 N_Derived_Type_Definition
)
615 and then D
= Constraint
(P
))
617 -- The constraint itself may be given by a subtype indication,
618 -- rather than by a more common discrete range.
620 or else (Nkind
(P
) = N_Subtype_Indication
622 Nkind
(Parent
(P
)) = N_Index_Or_Discriminant_Constraint
)
623 or else Nkind
(P
) = N_Entry_Declaration
624 or else Nkind
(D
) = N_Defining_Identifier
627 ("discriminant in constraint must appear alone", N
);
630 end Check_Discriminant_Use
;
632 --------------------------------
633 -- Check_For_Visible_Operator --
634 --------------------------------
636 procedure Check_For_Visible_Operator
(N
: Node_Id
; T
: Entity_Id
) is
638 if Is_Invisible_Operator
(N
, T
) then
639 Error_Msg_NE
-- CODEFIX
640 ("operator for} is not directly visible!", N
, First_Subtype
(T
));
641 Error_Msg_N
-- CODEFIX
642 ("use clause would make operation legal!", N
);
644 end Check_For_Visible_Operator
;
646 ----------------------------------
647 -- Check_Fully_Declared_Prefix --
648 ----------------------------------
650 procedure Check_Fully_Declared_Prefix
655 -- Check that the designated type of the prefix of a dereference is
656 -- not an incomplete type. This cannot be done unconditionally, because
657 -- dereferences of private types are legal in default expressions. This
658 -- case is taken care of in Check_Fully_Declared, called below. There
659 -- are also 2005 cases where it is legal for the prefix to be unfrozen.
661 -- This consideration also applies to similar checks for allocators,
662 -- qualified expressions, and type conversions.
664 -- An additional exception concerns other per-object expressions that
665 -- are not directly related to component declarations, in particular
666 -- representation pragmas for tasks. These will be per-object
667 -- expressions if they depend on discriminants or some global entity.
668 -- If the task has access discriminants, the designated type may be
669 -- incomplete at the point the expression is resolved. This resolution
670 -- takes place within the body of the initialization procedure, where
671 -- the discriminant is replaced by its discriminal.
673 if Is_Entity_Name
(Pref
)
674 and then Ekind
(Entity
(Pref
)) = E_In_Parameter
678 -- Ada 2005 (AI-326): Tagged incomplete types allowed. The wrong usages
679 -- are handled by Analyze_Access_Attribute, Analyze_Assignment,
680 -- Analyze_Object_Renaming, and Freeze_Entity.
682 elsif Ada_Version
>= Ada_2005
683 and then Is_Entity_Name
(Pref
)
684 and then Is_Access_Type
(Etype
(Pref
))
685 and then Ekind
(Directly_Designated_Type
(Etype
(Pref
))) =
687 and then Is_Tagged_Type
(Directly_Designated_Type
(Etype
(Pref
)))
691 Check_Fully_Declared
(Typ
, Parent
(Pref
));
693 end Check_Fully_Declared_Prefix
;
695 ------------------------------
696 -- Check_Infinite_Recursion --
697 ------------------------------
699 function Check_Infinite_Recursion
(N
: Node_Id
) return Boolean is
703 function Same_Argument_List
return Boolean;
704 -- Check whether list of actuals is identical to list of formals of
705 -- called function (which is also the enclosing scope).
707 ------------------------
708 -- Same_Argument_List --
709 ------------------------
711 function Same_Argument_List
return Boolean is
717 if not Is_Entity_Name
(Name
(N
)) then
720 Subp
:= Entity
(Name
(N
));
723 F
:= First_Formal
(Subp
);
724 A
:= First_Actual
(N
);
725 while Present
(F
) and then Present
(A
) loop
726 if not Is_Entity_Name
(A
) or else Entity
(A
) /= F
then
735 end Same_Argument_List
;
737 -- Start of processing for Check_Infinite_Recursion
740 -- Special case, if this is a procedure call and is a call to the
741 -- current procedure with the same argument list, then this is for
742 -- sure an infinite recursion and we insert a call to raise SE.
744 if Is_List_Member
(N
)
745 and then List_Length
(List_Containing
(N
)) = 1
746 and then Same_Argument_List
749 P
: constant Node_Id
:= Parent
(N
);
751 if Nkind
(P
) = N_Handled_Sequence_Of_Statements
752 and then Nkind
(Parent
(P
)) = N_Subprogram_Body
753 and then Is_Empty_List
(Declarations
(Parent
(P
)))
755 Error_Msg_Warn
:= SPARK_Mode
/= On
;
756 Error_Msg_N
("!infinite recursion<<", N
);
757 Error_Msg_N
("\!Storage_Error [<<", N
);
759 Make_Raise_Storage_Error
(Sloc
(N
),
760 Reason
=> SE_Infinite_Recursion
));
766 -- If not that special case, search up tree, quitting if we reach a
767 -- construct (e.g. a conditional) that tells us that this is not a
768 -- case for an infinite recursion warning.
774 -- If no parent, then we were not inside a subprogram, this can for
775 -- example happen when processing certain pragmas in a spec. Just
776 -- return False in this case.
782 -- Done if we get to subprogram body, this is definitely an infinite
783 -- recursion case if we did not find anything to stop us.
785 exit when Nkind
(P
) = N_Subprogram_Body
;
787 -- If appearing in conditional, result is false
789 if Nkind_In
(P
, N_Or_Else
,
798 elsif Nkind
(P
) = N_Handled_Sequence_Of_Statements
799 and then C
/= First
(Statements
(P
))
801 -- If the call is the expression of a return statement and the
802 -- actuals are identical to the formals, it's worth a warning.
803 -- However, we skip this if there is an immediately preceding
804 -- raise statement, since the call is never executed.
806 -- Furthermore, this corresponds to a common idiom:
808 -- function F (L : Thing) return Boolean is
810 -- raise Program_Error;
814 -- for generating a stub function
816 if Nkind
(Parent
(N
)) = N_Simple_Return_Statement
817 and then Same_Argument_List
819 exit when not Is_List_Member
(Parent
(N
));
821 -- OK, return statement is in a statement list, look for raise
827 -- Skip past N_Freeze_Entity nodes generated by expansion
829 Nod
:= Prev
(Parent
(N
));
831 and then Nkind
(Nod
) = N_Freeze_Entity
836 -- If no raise statement, give warning. We look at the
837 -- original node, because in the case of "raise ... with
838 -- ...", the node has been transformed into a call.
840 exit when Nkind
(Original_Node
(Nod
)) /= N_Raise_Statement
842 (Nkind
(Nod
) not in N_Raise_xxx_Error
843 or else Present
(Condition
(Nod
)));
854 Error_Msg_Warn
:= SPARK_Mode
/= On
;
855 Error_Msg_N
("!possible infinite recursion<<", N
);
856 Error_Msg_N
("\!??Storage_Error ]<<", N
);
859 end Check_Infinite_Recursion
;
861 -------------------------------
862 -- Check_Initialization_Call --
863 -------------------------------
865 procedure Check_Initialization_Call
(N
: Entity_Id
; Nam
: Entity_Id
) is
866 Typ
: constant Entity_Id
:= Etype
(First_Formal
(Nam
));
868 function Uses_SS
(T
: Entity_Id
) return Boolean;
869 -- Check whether the creation of an object of the type will involve
870 -- use of the secondary stack. If T is a record type, this is true
871 -- if the expression for some component uses the secondary stack, e.g.
872 -- through a call to a function that returns an unconstrained value.
873 -- False if T is controlled, because cleanups occur elsewhere.
879 function Uses_SS
(T
: Entity_Id
) return Boolean is
882 Full_Type
: Entity_Id
:= Underlying_Type
(T
);
885 -- Normally we want to use the underlying type, but if it's not set
886 -- then continue with T.
888 if not Present
(Full_Type
) then
892 if Is_Controlled
(Full_Type
) then
895 elsif Is_Array_Type
(Full_Type
) then
896 return Uses_SS
(Component_Type
(Full_Type
));
898 elsif Is_Record_Type
(Full_Type
) then
899 Comp
:= First_Component
(Full_Type
);
900 while Present
(Comp
) loop
901 if Ekind
(Comp
) = E_Component
902 and then Nkind
(Parent
(Comp
)) = N_Component_Declaration
904 -- The expression for a dynamic component may be rewritten
905 -- as a dereference, so retrieve original node.
907 Expr
:= Original_Node
(Expression
(Parent
(Comp
)));
909 -- Return True if the expression is a call to a function
910 -- (including an attribute function such as Image, or a
911 -- user-defined operator) with a result that requires a
914 if (Nkind
(Expr
) = N_Function_Call
915 or else Nkind
(Expr
) in N_Op
916 or else (Nkind
(Expr
) = N_Attribute_Reference
917 and then Present
(Expressions
(Expr
))))
918 and then Requires_Transient_Scope
(Etype
(Expr
))
922 elsif Uses_SS
(Etype
(Comp
)) then
927 Next_Component
(Comp
);
937 -- Start of processing for Check_Initialization_Call
940 -- Establish a transient scope if the type needs it
942 if Uses_SS
(Typ
) then
943 Establish_Transient_Scope
(First_Actual
(N
), Sec_Stack
=> True);
945 end Check_Initialization_Call
;
947 ---------------------------------------
948 -- Check_No_Direct_Boolean_Operators --
949 ---------------------------------------
951 procedure Check_No_Direct_Boolean_Operators
(N
: Node_Id
) is
953 if Scope
(Entity
(N
)) = Standard_Standard
954 and then Root_Type
(Etype
(Left_Opnd
(N
))) = Standard_Boolean
956 -- Restriction only applies to original source code
958 if Comes_From_Source
(N
) then
959 Check_Restriction
(No_Direct_Boolean_Operators
, N
);
963 -- Do style check (but skip if in instance, error is on template)
966 if not In_Instance
then
967 Check_Boolean_Operator
(N
);
970 end Check_No_Direct_Boolean_Operators
;
972 ------------------------------
973 -- Check_Parameterless_Call --
974 ------------------------------
976 procedure Check_Parameterless_Call
(N
: Node_Id
) is
979 function Prefix_Is_Access_Subp
return Boolean;
980 -- If the prefix is of an access_to_subprogram type, the node must be
981 -- rewritten as a call. Ditto if the prefix is overloaded and all its
982 -- interpretations are access to subprograms.
984 ---------------------------
985 -- Prefix_Is_Access_Subp --
986 ---------------------------
988 function Prefix_Is_Access_Subp
return Boolean is
993 -- If the context is an attribute reference that can apply to
994 -- functions, this is never a parameterless call (RM 4.1.4(6)).
996 if Nkind
(Parent
(N
)) = N_Attribute_Reference
997 and then Nam_In
(Attribute_Name
(Parent
(N
)), Name_Address
,
1004 if not Is_Overloaded
(N
) then
1006 Ekind
(Etype
(N
)) = E_Subprogram_Type
1007 and then Base_Type
(Etype
(Etype
(N
))) /= Standard_Void_Type
;
1009 Get_First_Interp
(N
, I
, It
);
1010 while Present
(It
.Typ
) loop
1011 if Ekind
(It
.Typ
) /= E_Subprogram_Type
1012 or else Base_Type
(Etype
(It
.Typ
)) = Standard_Void_Type
1017 Get_Next_Interp
(I
, It
);
1022 end Prefix_Is_Access_Subp
;
1024 -- Start of processing for Check_Parameterless_Call
1027 -- Defend against junk stuff if errors already detected
1029 if Total_Errors_Detected
/= 0 then
1030 if Nkind
(N
) in N_Has_Etype
and then Etype
(N
) = Any_Type
then
1032 elsif Nkind
(N
) in N_Has_Chars
1033 and then not Is_Valid_Name
(Chars
(N
))
1041 -- If the context expects a value, and the name is a procedure, this is
1042 -- most likely a missing 'Access. Don't try to resolve the parameterless
1043 -- call, error will be caught when the outer call is analyzed.
1045 if Is_Entity_Name
(N
)
1046 and then Ekind
(Entity
(N
)) = E_Procedure
1047 and then not Is_Overloaded
(N
)
1049 Nkind_In
(Parent
(N
), N_Parameter_Association
,
1051 N_Procedure_Call_Statement
)
1056 -- Rewrite as call if overloadable entity that is (or could be, in the
1057 -- overloaded case) a function call. If we know for sure that the entity
1058 -- is an enumeration literal, we do not rewrite it.
1060 -- If the entity is the name of an operator, it cannot be a call because
1061 -- operators cannot have default parameters. In this case, this must be
1062 -- a string whose contents coincide with an operator name. Set the kind
1063 -- of the node appropriately.
1065 if (Is_Entity_Name
(N
)
1066 and then Nkind
(N
) /= N_Operator_Symbol
1067 and then Is_Overloadable
(Entity
(N
))
1068 and then (Ekind
(Entity
(N
)) /= E_Enumeration_Literal
1069 or else Is_Overloaded
(N
)))
1071 -- Rewrite as call if it is an explicit dereference of an expression of
1072 -- a subprogram access type, and the subprogram type is not that of a
1073 -- procedure or entry.
1076 (Nkind
(N
) = N_Explicit_Dereference
and then Prefix_Is_Access_Subp
)
1078 -- Rewrite as call if it is a selected component which is a function,
1079 -- this is the case of a call to a protected function (which may be
1080 -- overloaded with other protected operations).
1083 (Nkind
(N
) = N_Selected_Component
1084 and then (Ekind
(Entity
(Selector_Name
(N
))) = E_Function
1086 (Ekind_In
(Entity
(Selector_Name
(N
)), E_Entry
,
1088 and then Is_Overloaded
(Selector_Name
(N
)))))
1090 -- If one of the above three conditions is met, rewrite as call. Apply
1091 -- the rewriting only once.
1094 if Nkind
(Parent
(N
)) /= N_Function_Call
1095 or else N
/= Name
(Parent
(N
))
1098 -- This may be a prefixed call that was not fully analyzed, e.g.
1099 -- an actual in an instance.
1101 if Ada_Version
>= Ada_2005
1102 and then Nkind
(N
) = N_Selected_Component
1103 and then Is_Dispatching_Operation
(Entity
(Selector_Name
(N
)))
1105 Analyze_Selected_Component
(N
);
1107 if Nkind
(N
) /= N_Selected_Component
then
1112 -- The node is the name of the parameterless call. Preserve its
1113 -- descendants, which may be complex expressions.
1115 Nam
:= Relocate_Node
(N
);
1117 -- If overloaded, overload set belongs to new copy
1119 Save_Interps
(N
, Nam
);
1121 -- Change node to parameterless function call (note that the
1122 -- Parameter_Associations associations field is left set to Empty,
1123 -- its normal default value since there are no parameters)
1125 Change_Node
(N
, N_Function_Call
);
1127 Set_Sloc
(N
, Sloc
(Nam
));
1131 elsif Nkind
(N
) = N_Parameter_Association
then
1132 Check_Parameterless_Call
(Explicit_Actual_Parameter
(N
));
1134 elsif Nkind
(N
) = N_Operator_Symbol
then
1135 Change_Operator_Symbol_To_String_Literal
(N
);
1136 Set_Is_Overloaded
(N
, False);
1137 Set_Etype
(N
, Any_String
);
1139 end Check_Parameterless_Call
;
1141 --------------------------------
1142 -- Is_Atomic_Ref_With_Address --
1143 --------------------------------
1145 function Is_Atomic_Ref_With_Address
(N
: Node_Id
) return Boolean is
1146 Pref
: constant Node_Id
:= Prefix
(N
);
1149 if not Is_Entity_Name
(Pref
) then
1154 Pent
: constant Entity_Id
:= Entity
(Pref
);
1155 Ptyp
: constant Entity_Id
:= Etype
(Pent
);
1157 return not Is_Access_Type
(Ptyp
)
1158 and then (Is_Atomic
(Ptyp
) or else Is_Atomic
(Pent
))
1159 and then Present
(Address_Clause
(Pent
));
1162 end Is_Atomic_Ref_With_Address
;
1164 -----------------------------
1165 -- Is_Definite_Access_Type --
1166 -----------------------------
1168 function Is_Definite_Access_Type
(E
: Entity_Id
) return Boolean is
1169 Btyp
: constant Entity_Id
:= Base_Type
(E
);
1171 return Ekind
(Btyp
) = E_Access_Type
1172 or else (Ekind
(Btyp
) = E_Access_Subprogram_Type
1173 and then Comes_From_Source
(Btyp
));
1174 end Is_Definite_Access_Type
;
1176 ----------------------
1177 -- Is_Predefined_Op --
1178 ----------------------
1180 function Is_Predefined_Op
(Nam
: Entity_Id
) return Boolean is
1182 -- Predefined operators are intrinsic subprograms
1184 if not Is_Intrinsic_Subprogram
(Nam
) then
1188 -- A call to a back-end builtin is never a predefined operator
1190 if Is_Imported
(Nam
) and then Present
(Interface_Name
(Nam
)) then
1194 return not Is_Generic_Instance
(Nam
)
1195 and then Chars
(Nam
) in Any_Operator_Name
1196 and then (No
(Alias
(Nam
)) or else Is_Predefined_Op
(Alias
(Nam
)));
1197 end Is_Predefined_Op
;
1199 -----------------------------
1200 -- Make_Call_Into_Operator --
1201 -----------------------------
1203 procedure Make_Call_Into_Operator
1208 Op_Name
: constant Name_Id
:= Chars
(Op_Id
);
1209 Act1
: Node_Id
:= First_Actual
(N
);
1210 Act2
: Node_Id
:= Next_Actual
(Act1
);
1211 Error
: Boolean := False;
1212 Func
: constant Entity_Id
:= Entity
(Name
(N
));
1213 Is_Binary
: constant Boolean := Present
(Act2
);
1215 Opnd_Type
: Entity_Id
:= Empty
;
1216 Orig_Type
: Entity_Id
:= Empty
;
1219 type Kind_Test
is access function (E
: Entity_Id
) return Boolean;
1221 function Operand_Type_In_Scope
(S
: Entity_Id
) return Boolean;
1222 -- If the operand is not universal, and the operator is given by an
1223 -- expanded name, verify that the operand has an interpretation with a
1224 -- type defined in the given scope of the operator.
1226 function Type_In_P
(Test
: Kind_Test
) return Entity_Id
;
1227 -- Find a type of the given class in package Pack that contains the
1230 ---------------------------
1231 -- Operand_Type_In_Scope --
1232 ---------------------------
1234 function Operand_Type_In_Scope
(S
: Entity_Id
) return Boolean is
1235 Nod
: constant Node_Id
:= Right_Opnd
(Op_Node
);
1240 if not Is_Overloaded
(Nod
) then
1241 return Scope
(Base_Type
(Etype
(Nod
))) = S
;
1244 Get_First_Interp
(Nod
, I
, It
);
1245 while Present
(It
.Typ
) loop
1246 if Scope
(Base_Type
(It
.Typ
)) = S
then
1250 Get_Next_Interp
(I
, It
);
1255 end Operand_Type_In_Scope
;
1261 function Type_In_P
(Test
: Kind_Test
) return Entity_Id
is
1264 function In_Decl
return Boolean;
1265 -- Verify that node is not part of the type declaration for the
1266 -- candidate type, which would otherwise be invisible.
1272 function In_Decl
return Boolean is
1273 Decl_Node
: constant Node_Id
:= Parent
(E
);
1279 if Etype
(E
) = Any_Type
then
1282 elsif No
(Decl_Node
) then
1287 and then Nkind
(N2
) /= N_Compilation_Unit
1289 if N2
= Decl_Node
then
1300 -- Start of processing for Type_In_P
1303 -- If the context type is declared in the prefix package, this is the
1304 -- desired base type.
1306 if Scope
(Base_Type
(Typ
)) = Pack
and then Test
(Typ
) then
1307 return Base_Type
(Typ
);
1310 E
:= First_Entity
(Pack
);
1311 while Present
(E
) loop
1312 if Test
(E
) and then not In_Decl
then
1323 -- Start of processing for Make_Call_Into_Operator
1326 Op_Node
:= New_Node
(Operator_Kind
(Op_Name
, Is_Binary
), Sloc
(N
));
1328 -- Ensure that the corresponding operator has the same parent as the
1329 -- original call. This guarantees that parent traversals performed by
1330 -- the ABE mechanism succeed.
1332 Set_Parent
(Op_Node
, Parent
(N
));
1337 Set_Left_Opnd
(Op_Node
, Relocate_Node
(Act1
));
1338 Set_Right_Opnd
(Op_Node
, Relocate_Node
(Act2
));
1339 Save_Interps
(Act1
, Left_Opnd
(Op_Node
));
1340 Save_Interps
(Act2
, Right_Opnd
(Op_Node
));
1341 Act1
:= Left_Opnd
(Op_Node
);
1342 Act2
:= Right_Opnd
(Op_Node
);
1347 Set_Right_Opnd
(Op_Node
, Relocate_Node
(Act1
));
1348 Save_Interps
(Act1
, Right_Opnd
(Op_Node
));
1349 Act1
:= Right_Opnd
(Op_Node
);
1352 -- If the operator is denoted by an expanded name, and the prefix is
1353 -- not Standard, but the operator is a predefined one whose scope is
1354 -- Standard, then this is an implicit_operator, inserted as an
1355 -- interpretation by the procedure of the same name. This procedure
1356 -- overestimates the presence of implicit operators, because it does
1357 -- not examine the type of the operands. Verify now that the operand
1358 -- type appears in the given scope. If right operand is universal,
1359 -- check the other operand. In the case of concatenation, either
1360 -- argument can be the component type, so check the type of the result.
1361 -- If both arguments are literals, look for a type of the right kind
1362 -- defined in the given scope. This elaborate nonsense is brought to
1363 -- you courtesy of b33302a. The type itself must be frozen, so we must
1364 -- find the type of the proper class in the given scope.
1366 -- A final wrinkle is the multiplication operator for fixed point types,
1367 -- which is defined in Standard only, and not in the scope of the
1368 -- fixed point type itself.
1370 if Nkind
(Name
(N
)) = N_Expanded_Name
then
1371 Pack
:= Entity
(Prefix
(Name
(N
)));
1373 -- If this is a package renaming, get renamed entity, which will be
1374 -- the scope of the operands if operaton is type-correct.
1376 if Present
(Renamed_Entity
(Pack
)) then
1377 Pack
:= Renamed_Entity
(Pack
);
1380 -- If the entity being called is defined in the given package, it is
1381 -- a renaming of a predefined operator, and known to be legal.
1383 if Scope
(Entity
(Name
(N
))) = Pack
1384 and then Pack
/= Standard_Standard
1388 -- Visibility does not need to be checked in an instance: if the
1389 -- operator was not visible in the generic it has been diagnosed
1390 -- already, else there is an implicit copy of it in the instance.
1392 elsif In_Instance
then
1395 elsif Nam_In
(Op_Name
, Name_Op_Multiply
, Name_Op_Divide
)
1396 and then Is_Fixed_Point_Type
(Etype
(Left_Opnd
(Op_Node
)))
1397 and then Is_Fixed_Point_Type
(Etype
(Right_Opnd
(Op_Node
)))
1399 if Pack
/= Standard_Standard
then
1403 -- Ada 2005 AI-420: Predefined equality on Universal_Access is
1406 elsif Ada_Version
>= Ada_2005
1407 and then Nam_In
(Op_Name
, Name_Op_Eq
, Name_Op_Ne
)
1408 and then Ekind
(Etype
(Act1
)) = E_Anonymous_Access_Type
1413 Opnd_Type
:= Base_Type
(Etype
(Right_Opnd
(Op_Node
)));
1415 if Op_Name
= Name_Op_Concat
then
1416 Opnd_Type
:= Base_Type
(Typ
);
1418 elsif (Scope
(Opnd_Type
) = Standard_Standard
1420 or else (Nkind
(Right_Opnd
(Op_Node
)) = N_Attribute_Reference
1422 and then not Comes_From_Source
(Opnd_Type
))
1424 Opnd_Type
:= Base_Type
(Etype
(Left_Opnd
(Op_Node
)));
1427 if Scope
(Opnd_Type
) = Standard_Standard
then
1429 -- Verify that the scope contains a type that corresponds to
1430 -- the given literal. Optimize the case where Pack is Standard.
1432 if Pack
/= Standard_Standard
then
1433 if Opnd_Type
= Universal_Integer
then
1434 Orig_Type
:= Type_In_P
(Is_Integer_Type
'Access);
1436 elsif Opnd_Type
= Universal_Real
then
1437 Orig_Type
:= Type_In_P
(Is_Real_Type
'Access);
1439 elsif Opnd_Type
= Any_String
then
1440 Orig_Type
:= Type_In_P
(Is_String_Type
'Access);
1442 elsif Opnd_Type
= Any_Access
then
1443 Orig_Type
:= Type_In_P
(Is_Definite_Access_Type
'Access);
1445 elsif Opnd_Type
= Any_Composite
then
1446 Orig_Type
:= Type_In_P
(Is_Composite_Type
'Access);
1448 if Present
(Orig_Type
) then
1449 if Has_Private_Component
(Orig_Type
) then
1452 Set_Etype
(Act1
, Orig_Type
);
1455 Set_Etype
(Act2
, Orig_Type
);
1464 Error
:= No
(Orig_Type
);
1467 elsif Ekind
(Opnd_Type
) = E_Allocator_Type
1468 and then No
(Type_In_P
(Is_Definite_Access_Type
'Access))
1472 -- If the type is defined elsewhere, and the operator is not
1473 -- defined in the given scope (by a renaming declaration, e.g.)
1474 -- then this is an error as well. If an extension of System is
1475 -- present, and the type may be defined there, Pack must be
1478 elsif Scope
(Opnd_Type
) /= Pack
1479 and then Scope
(Op_Id
) /= Pack
1480 and then (No
(System_Aux_Id
)
1481 or else Scope
(Opnd_Type
) /= System_Aux_Id
1482 or else Pack
/= Scope
(System_Aux_Id
))
1484 if not Is_Overloaded
(Right_Opnd
(Op_Node
)) then
1487 Error
:= not Operand_Type_In_Scope
(Pack
);
1490 elsif Pack
= Standard_Standard
1491 and then not Operand_Type_In_Scope
(Standard_Standard
)
1498 Error_Msg_Node_2
:= Pack
;
1500 ("& not declared in&", N
, Selector_Name
(Name
(N
)));
1501 Set_Etype
(N
, Any_Type
);
1504 -- Detect a mismatch between the context type and the result type
1505 -- in the named package, which is otherwise not detected if the
1506 -- operands are universal. Check is only needed if source entity is
1507 -- an operator, not a function that renames an operator.
1509 elsif Nkind
(Parent
(N
)) /= N_Type_Conversion
1510 and then Ekind
(Entity
(Name
(N
))) = E_Operator
1511 and then Is_Numeric_Type
(Typ
)
1512 and then not Is_Universal_Numeric_Type
(Typ
)
1513 and then Scope
(Base_Type
(Typ
)) /= Pack
1514 and then not In_Instance
1516 if Is_Fixed_Point_Type
(Typ
)
1517 and then Nam_In
(Op_Name
, Name_Op_Multiply
, Name_Op_Divide
)
1519 -- Already checked above
1523 -- Operator may be defined in an extension of System
1525 elsif Present
(System_Aux_Id
)
1526 and then Present
(Opnd_Type
)
1527 and then Scope
(Opnd_Type
) = System_Aux_Id
1532 -- Could we use Wrong_Type here??? (this would require setting
1533 -- Etype (N) to the actual type found where Typ was expected).
1535 Error_Msg_NE
("expect }", N
, Typ
);
1540 Set_Chars
(Op_Node
, Op_Name
);
1542 if not Is_Private_Type
(Etype
(N
)) then
1543 Set_Etype
(Op_Node
, Base_Type
(Etype
(N
)));
1545 Set_Etype
(Op_Node
, Etype
(N
));
1548 -- If this is a call to a function that renames a predefined equality,
1549 -- the renaming declaration provides a type that must be used to
1550 -- resolve the operands. This must be done now because resolution of
1551 -- the equality node will not resolve any remaining ambiguity, and it
1552 -- assumes that the first operand is not overloaded.
1554 if Nam_In
(Op_Name
, Name_Op_Eq
, Name_Op_Ne
)
1555 and then Ekind
(Func
) = E_Function
1556 and then Is_Overloaded
(Act1
)
1558 Resolve
(Act1
, Base_Type
(Etype
(First_Formal
(Func
))));
1559 Resolve
(Act2
, Base_Type
(Etype
(First_Formal
(Func
))));
1562 Set_Entity
(Op_Node
, Op_Id
);
1563 Generate_Reference
(Op_Id
, N
, ' ');
1565 -- Do rewrite setting Comes_From_Source on the result if the original
1566 -- call came from source. Although it is not strictly the case that the
1567 -- operator as such comes from the source, logically it corresponds
1568 -- exactly to the function call in the source, so it should be marked
1569 -- this way (e.g. to make sure that validity checks work fine).
1572 CS
: constant Boolean := Comes_From_Source
(N
);
1574 Rewrite
(N
, Op_Node
);
1575 Set_Comes_From_Source
(N
, CS
);
1578 -- If this is an arithmetic operator and the result type is private,
1579 -- the operands and the result must be wrapped in conversion to
1580 -- expose the underlying numeric type and expand the proper checks,
1581 -- e.g. on division.
1583 if Is_Private_Type
(Typ
) then
1593 Resolve_Intrinsic_Operator
(N
, Typ
);
1599 Resolve_Intrinsic_Unary_Operator
(N
, Typ
);
1608 -- If in ASIS_Mode, propagate operand types to original actuals of
1609 -- function call, which would otherwise not be fully resolved. If
1610 -- the call has already been constant-folded, nothing to do. We
1611 -- relocate the operand nodes rather than copy them, to preserve
1612 -- original_node pointers, given that the operands themselves may
1613 -- have been rewritten. If the call was itself a rewriting of an
1614 -- operator node, nothing to do.
1617 and then Nkind
(N
) in N_Op
1618 and then Nkind
(Original_Node
(N
)) = N_Function_Call
1622 R
: constant Node_Id
:= Right_Opnd
(N
);
1624 Old_First
: constant Node_Id
:=
1625 First
(Parameter_Associations
(Original_Node
(N
)));
1631 Old_Sec
:= Next
(Old_First
);
1633 -- If the original call has named associations, replace the
1634 -- explicit actual parameter in the association with the proper
1635 -- resolved operand.
1637 if Nkind
(Old_First
) = N_Parameter_Association
then
1638 if Chars
(Selector_Name
(Old_First
)) =
1639 Chars
(First_Entity
(Op_Id
))
1641 Rewrite
(Explicit_Actual_Parameter
(Old_First
),
1644 Rewrite
(Explicit_Actual_Parameter
(Old_First
),
1649 Rewrite
(Old_First
, Relocate_Node
(L
));
1652 if Nkind
(Old_Sec
) = N_Parameter_Association
then
1653 if Chars
(Selector_Name
(Old_Sec
)) =
1654 Chars
(First_Entity
(Op_Id
))
1656 Rewrite
(Explicit_Actual_Parameter
(Old_Sec
),
1659 Rewrite
(Explicit_Actual_Parameter
(Old_Sec
),
1664 Rewrite
(Old_Sec
, Relocate_Node
(R
));
1668 if Nkind
(Old_First
) = N_Parameter_Association
then
1669 Rewrite
(Explicit_Actual_Parameter
(Old_First
),
1672 Rewrite
(Old_First
, Relocate_Node
(R
));
1677 Set_Parent
(Original_Node
(N
), Parent
(N
));
1679 end Make_Call_Into_Operator
;
1685 function Operator_Kind
1687 Is_Binary
: Boolean) return Node_Kind
1692 -- Use CASE statement or array???
1695 if Op_Name
= Name_Op_And
then
1697 elsif Op_Name
= Name_Op_Or
then
1699 elsif Op_Name
= Name_Op_Xor
then
1701 elsif Op_Name
= Name_Op_Eq
then
1703 elsif Op_Name
= Name_Op_Ne
then
1705 elsif Op_Name
= Name_Op_Lt
then
1707 elsif Op_Name
= Name_Op_Le
then
1709 elsif Op_Name
= Name_Op_Gt
then
1711 elsif Op_Name
= Name_Op_Ge
then
1713 elsif Op_Name
= Name_Op_Add
then
1715 elsif Op_Name
= Name_Op_Subtract
then
1716 Kind
:= N_Op_Subtract
;
1717 elsif Op_Name
= Name_Op_Concat
then
1718 Kind
:= N_Op_Concat
;
1719 elsif Op_Name
= Name_Op_Multiply
then
1720 Kind
:= N_Op_Multiply
;
1721 elsif Op_Name
= Name_Op_Divide
then
1722 Kind
:= N_Op_Divide
;
1723 elsif Op_Name
= Name_Op_Mod
then
1725 elsif Op_Name
= Name_Op_Rem
then
1727 elsif Op_Name
= Name_Op_Expon
then
1730 raise Program_Error
;
1736 if Op_Name
= Name_Op_Add
then
1738 elsif Op_Name
= Name_Op_Subtract
then
1740 elsif Op_Name
= Name_Op_Abs
then
1742 elsif Op_Name
= Name_Op_Not
then
1745 raise Program_Error
;
1752 ----------------------------
1753 -- Preanalyze_And_Resolve --
1754 ----------------------------
1756 procedure Preanalyze_And_Resolve
(N
: Node_Id
; T
: Entity_Id
) is
1757 Save_Full_Analysis
: constant Boolean := Full_Analysis
;
1760 Full_Analysis
:= False;
1761 Expander_Mode_Save_And_Set
(False);
1763 -- Normally, we suppress all checks for this preanalysis. There is no
1764 -- point in processing them now, since they will be applied properly
1765 -- and in the proper location when the default expressions reanalyzed
1766 -- and reexpanded later on. We will also have more information at that
1767 -- point for possible suppression of individual checks.
1769 -- However, in SPARK mode, most expansion is suppressed, and this
1770 -- later reanalysis and reexpansion may not occur. SPARK mode does
1771 -- require the setting of checking flags for proof purposes, so we
1772 -- do the SPARK preanalysis without suppressing checks.
1774 -- This special handling for SPARK mode is required for example in the
1775 -- case of Ada 2012 constructs such as quantified expressions, which are
1776 -- expanded in two separate steps.
1778 if GNATprove_Mode
then
1779 Analyze_And_Resolve
(N
, T
);
1781 Analyze_And_Resolve
(N
, T
, Suppress
=> All_Checks
);
1784 Expander_Mode_Restore
;
1785 Full_Analysis
:= Save_Full_Analysis
;
1786 end Preanalyze_And_Resolve
;
1788 -- Version without context type
1790 procedure Preanalyze_And_Resolve
(N
: Node_Id
) is
1791 Save_Full_Analysis
: constant Boolean := Full_Analysis
;
1794 Full_Analysis
:= False;
1795 Expander_Mode_Save_And_Set
(False);
1798 Resolve
(N
, Etype
(N
), Suppress
=> All_Checks
);
1800 Expander_Mode_Restore
;
1801 Full_Analysis
:= Save_Full_Analysis
;
1802 end Preanalyze_And_Resolve
;
1804 ----------------------------------
1805 -- Replace_Actual_Discriminants --
1806 ----------------------------------
1808 procedure Replace_Actual_Discriminants
(N
: Node_Id
; Default
: Node_Id
) is
1809 Loc
: constant Source_Ptr
:= Sloc
(N
);
1810 Tsk
: Node_Id
:= Empty
;
1812 function Process_Discr
(Nod
: Node_Id
) return Traverse_Result
;
1813 -- Comment needed???
1819 function Process_Discr
(Nod
: Node_Id
) return Traverse_Result
is
1823 if Nkind
(Nod
) = N_Identifier
then
1824 Ent
:= Entity
(Nod
);
1827 and then Ekind
(Ent
) = E_Discriminant
1830 Make_Selected_Component
(Loc
,
1831 Prefix
=> New_Copy_Tree
(Tsk
, New_Sloc
=> Loc
),
1832 Selector_Name
=> Make_Identifier
(Loc
, Chars
(Ent
))));
1834 Set_Etype
(Nod
, Etype
(Ent
));
1842 procedure Replace_Discrs
is new Traverse_Proc
(Process_Discr
);
1844 -- Start of processing for Replace_Actual_Discriminants
1847 if Expander_Active
then
1850 -- Allow the replacement of concurrent discriminants in GNATprove even
1851 -- though this is a light expansion activity. Note that generic units
1852 -- are not modified.
1854 elsif GNATprove_Mode
and not Inside_A_Generic
then
1861 if Nkind
(Name
(N
)) = N_Selected_Component
then
1862 Tsk
:= Prefix
(Name
(N
));
1864 elsif Nkind
(Name
(N
)) = N_Indexed_Component
then
1865 Tsk
:= Prefix
(Prefix
(Name
(N
)));
1868 if Present
(Tsk
) then
1869 Replace_Discrs
(Default
);
1871 end Replace_Actual_Discriminants
;
1877 procedure Resolve
(N
: Node_Id
; Typ
: Entity_Id
) is
1878 Ambiguous
: Boolean := False;
1879 Ctx_Type
: Entity_Id
:= Typ
;
1880 Expr_Type
: Entity_Id
:= Empty
; -- prevent junk warning
1881 Err_Type
: Entity_Id
:= Empty
;
1882 Found
: Boolean := False;
1885 I1
: Interp_Index
:= 0; -- prevent junk warning
1888 Seen
: Entity_Id
:= Empty
; -- prevent junk warning
1890 function Comes_From_Predefined_Lib_Unit
(Nod
: Node_Id
) return Boolean;
1891 -- Determine whether a node comes from a predefined library unit or
1894 procedure Patch_Up_Value
(N
: Node_Id
; Typ
: Entity_Id
);
1895 -- Try and fix up a literal so that it matches its expected type. New
1896 -- literals are manufactured if necessary to avoid cascaded errors.
1898 procedure Report_Ambiguous_Argument
;
1899 -- Additional diagnostics when an ambiguous call has an ambiguous
1900 -- argument (typically a controlling actual).
1902 procedure Resolution_Failed
;
1903 -- Called when attempt at resolving current expression fails
1905 ------------------------------------
1906 -- Comes_From_Predefined_Lib_Unit --
1907 -------------------------------------
1909 function Comes_From_Predefined_Lib_Unit
(Nod
: Node_Id
) return Boolean is
1912 Sloc
(Nod
) = Standard_Location
or else In_Predefined_Unit
(Nod
);
1913 end Comes_From_Predefined_Lib_Unit
;
1915 --------------------
1916 -- Patch_Up_Value --
1917 --------------------
1919 procedure Patch_Up_Value
(N
: Node_Id
; Typ
: Entity_Id
) is
1921 if Nkind
(N
) = N_Integer_Literal
and then Is_Real_Type
(Typ
) then
1923 Make_Real_Literal
(Sloc
(N
),
1924 Realval
=> UR_From_Uint
(Intval
(N
))));
1925 Set_Etype
(N
, Universal_Real
);
1926 Set_Is_Static_Expression
(N
);
1928 elsif Nkind
(N
) = N_Real_Literal
and then Is_Integer_Type
(Typ
) then
1930 Make_Integer_Literal
(Sloc
(N
),
1931 Intval
=> UR_To_Uint
(Realval
(N
))));
1932 Set_Etype
(N
, Universal_Integer
);
1933 Set_Is_Static_Expression
(N
);
1935 elsif Nkind
(N
) = N_String_Literal
1936 and then Is_Character_Type
(Typ
)
1938 Set_Character_Literal_Name
(Char_Code
(Character'Pos ('A')));
1940 Make_Character_Literal
(Sloc
(N
),
1942 Char_Literal_Value
=>
1943 UI_From_Int
(Character'Pos ('A'))));
1944 Set_Etype
(N
, Any_Character
);
1945 Set_Is_Static_Expression
(N
);
1947 elsif Nkind
(N
) /= N_String_Literal
and then Is_String_Type
(Typ
) then
1949 Make_String_Literal
(Sloc
(N
),
1950 Strval
=> End_String
));
1952 elsif Nkind
(N
) = N_Range
then
1953 Patch_Up_Value
(Low_Bound
(N
), Typ
);
1954 Patch_Up_Value
(High_Bound
(N
), Typ
);
1958 -------------------------------
1959 -- Report_Ambiguous_Argument --
1960 -------------------------------
1962 procedure Report_Ambiguous_Argument
is
1963 Arg
: constant Node_Id
:= First
(Parameter_Associations
(N
));
1968 if Nkind
(Arg
) = N_Function_Call
1969 and then Is_Entity_Name
(Name
(Arg
))
1970 and then Is_Overloaded
(Name
(Arg
))
1972 Error_Msg_NE
("ambiguous call to&", Arg
, Name
(Arg
));
1974 -- Could use comments on what is going on here???
1976 Get_First_Interp
(Name
(Arg
), I
, It
);
1977 while Present
(It
.Nam
) loop
1978 Error_Msg_Sloc
:= Sloc
(It
.Nam
);
1980 if Nkind
(Parent
(It
.Nam
)) = N_Full_Type_Declaration
then
1981 Error_Msg_N
("interpretation (inherited) #!", Arg
);
1983 Error_Msg_N
("interpretation #!", Arg
);
1986 Get_Next_Interp
(I
, It
);
1989 end Report_Ambiguous_Argument
;
1991 -----------------------
1992 -- Resolution_Failed --
1993 -----------------------
1995 procedure Resolution_Failed
is
1997 Patch_Up_Value
(N
, Typ
);
1999 -- Set the type to the desired one to minimize cascaded errors. Note
2000 -- that this is an approximation and does not work in all cases.
2004 Debug_A_Exit
("resolving ", N
, " (done, resolution failed)");
2005 Set_Is_Overloaded
(N
, False);
2007 -- The caller will return without calling the expander, so we need
2008 -- to set the analyzed flag. Note that it is fine to set Analyzed
2009 -- to True even if we are in the middle of a shallow analysis,
2010 -- (see the spec of sem for more details) since this is an error
2011 -- situation anyway, and there is no point in repeating the
2012 -- analysis later (indeed it won't work to repeat it later, since
2013 -- we haven't got a clear resolution of which entity is being
2016 Set_Analyzed
(N
, True);
2018 end Resolution_Failed
;
2020 -- Start of processing for Resolve
2027 -- Access attribute on remote subprogram cannot be used for a non-remote
2028 -- access-to-subprogram type.
2030 if Nkind
(N
) = N_Attribute_Reference
2031 and then Nam_In
(Attribute_Name
(N
), Name_Access
,
2032 Name_Unrestricted_Access
,
2033 Name_Unchecked_Access
)
2034 and then Comes_From_Source
(N
)
2035 and then Is_Entity_Name
(Prefix
(N
))
2036 and then Is_Subprogram
(Entity
(Prefix
(N
)))
2037 and then Is_Remote_Call_Interface
(Entity
(Prefix
(N
)))
2038 and then not Is_Remote_Access_To_Subprogram_Type
(Typ
)
2041 ("prefix must statically denote a non-remote subprogram", N
);
2044 From_Lib
:= Comes_From_Predefined_Lib_Unit
(N
);
2046 -- If the context is a Remote_Access_To_Subprogram, access attributes
2047 -- must be resolved with the corresponding fat pointer. There is no need
2048 -- to check for the attribute name since the return type of an
2049 -- attribute is never a remote type.
2051 if Nkind
(N
) = N_Attribute_Reference
2052 and then Comes_From_Source
(N
)
2053 and then (Is_Remote_Call_Interface
(Typ
) or else Is_Remote_Types
(Typ
))
2056 Attr
: constant Attribute_Id
:=
2057 Get_Attribute_Id
(Attribute_Name
(N
));
2058 Pref
: constant Node_Id
:= Prefix
(N
);
2061 Is_Remote
: Boolean := True;
2064 -- Check that Typ is a remote access-to-subprogram type
2066 if Is_Remote_Access_To_Subprogram_Type
(Typ
) then
2068 -- Prefix (N) must statically denote a remote subprogram
2069 -- declared in a package specification.
2071 if Attr
= Attribute_Access
or else
2072 Attr
= Attribute_Unchecked_Access
or else
2073 Attr
= Attribute_Unrestricted_Access
2075 Decl
:= Unit_Declaration_Node
(Entity
(Pref
));
2077 if Nkind
(Decl
) = N_Subprogram_Body
then
2078 Spec
:= Corresponding_Spec
(Decl
);
2080 if Present
(Spec
) then
2081 Decl
:= Unit_Declaration_Node
(Spec
);
2085 Spec
:= Parent
(Decl
);
2087 if not Is_Entity_Name
(Prefix
(N
))
2088 or else Nkind
(Spec
) /= N_Package_Specification
2090 not Is_Remote_Call_Interface
(Defining_Entity
(Spec
))
2094 ("prefix must statically denote a remote subprogram ",
2098 -- If we are generating code in distributed mode, perform
2099 -- semantic checks against corresponding remote entities.
2102 and then Get_PCS_Name
/= Name_No_DSA
2104 Check_Subtype_Conformant
2105 (New_Id
=> Entity
(Prefix
(N
)),
2106 Old_Id
=> Designated_Type
2107 (Corresponding_Remote_Type
(Typ
)),
2111 Process_Remote_AST_Attribute
(N
, Typ
);
2119 Debug_A_Entry
("resolving ", N
);
2121 if Debug_Flag_V
then
2122 Write_Overloads
(N
);
2125 if Comes_From_Source
(N
) then
2126 if Is_Fixed_Point_Type
(Typ
) then
2127 Check_Restriction
(No_Fixed_Point
, N
);
2129 elsif Is_Floating_Point_Type
(Typ
)
2130 and then Typ
/= Universal_Real
2131 and then Typ
/= Any_Real
2133 Check_Restriction
(No_Floating_Point
, N
);
2137 -- Return if already analyzed
2139 if Analyzed
(N
) then
2140 Debug_A_Exit
("resolving ", N
, " (done, already analyzed)");
2141 Analyze_Dimension
(N
);
2144 -- Any case of Any_Type as the Etype value means that we had a
2147 elsif Etype
(N
) = Any_Type
then
2148 Debug_A_Exit
("resolving ", N
, " (done, Etype = Any_Type)");
2152 Check_Parameterless_Call
(N
);
2154 -- The resolution of an Expression_With_Actions is determined by
2157 if Nkind
(N
) = N_Expression_With_Actions
then
2158 Resolve
(Expression
(N
), Typ
);
2161 Expr_Type
:= Etype
(Expression
(N
));
2163 -- If not overloaded, then we know the type, and all that needs doing
2164 -- is to check that this type is compatible with the context.
2166 elsif not Is_Overloaded
(N
) then
2167 Found
:= Covers
(Typ
, Etype
(N
));
2168 Expr_Type
:= Etype
(N
);
2170 -- In the overloaded case, we must select the interpretation that
2171 -- is compatible with the context (i.e. the type passed to Resolve)
2174 -- Loop through possible interpretations
2176 Get_First_Interp
(N
, I
, It
);
2177 Interp_Loop
: while Present
(It
.Typ
) loop
2178 if Debug_Flag_V
then
2179 Write_Str
("Interp: ");
2183 -- We are only interested in interpretations that are compatible
2184 -- with the expected type, any other interpretations are ignored.
2186 if not Covers
(Typ
, It
.Typ
) then
2187 if Debug_Flag_V
then
2188 Write_Str
(" interpretation incompatible with context");
2193 -- Skip the current interpretation if it is disabled by an
2194 -- abstract operator. This action is performed only when the
2195 -- type against which we are resolving is the same as the
2196 -- type of the interpretation.
2198 if Ada_Version
>= Ada_2005
2199 and then It
.Typ
= Typ
2200 and then Typ
/= Universal_Integer
2201 and then Typ
/= Universal_Real
2202 and then Present
(It
.Abstract_Op
)
2204 if Debug_Flag_V
then
2205 Write_Line
("Skip.");
2211 -- First matching interpretation
2217 Expr_Type
:= It
.Typ
;
2219 -- Matching interpretation that is not the first, maybe an
2220 -- error, but there are some cases where preference rules are
2221 -- used to choose between the two possibilities. These and
2222 -- some more obscure cases are handled in Disambiguate.
2225 -- If the current statement is part of a predefined library
2226 -- unit, then all interpretations which come from user level
2227 -- packages should not be considered. Check previous and
2231 if not Comes_From_Predefined_Lib_Unit
(It
.Nam
) then
2234 elsif not Comes_From_Predefined_Lib_Unit
(Seen
) then
2236 -- Previous interpretation must be discarded
2240 Expr_Type
:= It
.Typ
;
2241 Set_Entity
(N
, Seen
);
2246 -- Otherwise apply further disambiguation steps
2248 Error_Msg_Sloc
:= Sloc
(Seen
);
2249 It1
:= Disambiguate
(N
, I1
, I
, Typ
);
2251 -- Disambiguation has succeeded. Skip the remaining
2254 if It1
/= No_Interp
then
2256 Expr_Type
:= It1
.Typ
;
2258 while Present
(It
.Typ
) loop
2259 Get_Next_Interp
(I
, It
);
2263 -- Before we issue an ambiguity complaint, check for the
2264 -- case of a subprogram call where at least one of the
2265 -- arguments is Any_Type, and if so suppress the message,
2266 -- since it is a cascaded error. This can also happen for
2267 -- a generalized indexing operation.
2269 if Nkind
(N
) in N_Subprogram_Call
2270 or else (Nkind
(N
) = N_Indexed_Component
2271 and then Present
(Generalized_Indexing
(N
)))
2278 if Nkind
(N
) = N_Indexed_Component
then
2279 Rewrite
(N
, Generalized_Indexing
(N
));
2282 A
:= First_Actual
(N
);
2283 while Present
(A
) loop
2286 if Nkind
(E
) = N_Parameter_Association
then
2287 E
:= Explicit_Actual_Parameter
(E
);
2290 if Etype
(E
) = Any_Type
then
2291 if Debug_Flag_V
then
2292 Write_Str
("Any_Type in call");
2303 elsif Nkind
(N
) in N_Binary_Op
2304 and then (Etype
(Left_Opnd
(N
)) = Any_Type
2305 or else Etype
(Right_Opnd
(N
)) = Any_Type
)
2309 elsif Nkind
(N
) in N_Unary_Op
2310 and then Etype
(Right_Opnd
(N
)) = Any_Type
2315 -- Not that special case, so issue message using the flag
2316 -- Ambiguous to control printing of the header message
2317 -- only at the start of an ambiguous set.
2319 if not Ambiguous
then
2320 if Nkind
(N
) = N_Function_Call
2321 and then Nkind
(Name
(N
)) = N_Explicit_Dereference
2324 ("ambiguous expression (cannot resolve indirect "
2327 Error_Msg_NE
-- CODEFIX
2328 ("ambiguous expression (cannot resolve&)!",
2334 if Nkind
(Parent
(Seen
)) = N_Full_Type_Declaration
then
2336 ("\\possible interpretation (inherited)#!", N
);
2338 Error_Msg_N
-- CODEFIX
2339 ("\\possible interpretation#!", N
);
2342 if Nkind
(N
) in N_Subprogram_Call
2343 and then Present
(Parameter_Associations
(N
))
2345 Report_Ambiguous_Argument
;
2349 Error_Msg_Sloc
:= Sloc
(It
.Nam
);
2351 -- By default, the error message refers to the candidate
2352 -- interpretation. But if it is a predefined operator, it
2353 -- is implicitly declared at the declaration of the type
2354 -- of the operand. Recover the sloc of that declaration
2355 -- for the error message.
2357 if Nkind
(N
) in N_Op
2358 and then Scope
(It
.Nam
) = Standard_Standard
2359 and then not Is_Overloaded
(Right_Opnd
(N
))
2360 and then Scope
(Base_Type
(Etype
(Right_Opnd
(N
)))) /=
2363 Err_Type
:= First_Subtype
(Etype
(Right_Opnd
(N
)));
2365 if Comes_From_Source
(Err_Type
)
2366 and then Present
(Parent
(Err_Type
))
2368 Error_Msg_Sloc
:= Sloc
(Parent
(Err_Type
));
2371 elsif Nkind
(N
) in N_Binary_Op
2372 and then Scope
(It
.Nam
) = Standard_Standard
2373 and then not Is_Overloaded
(Left_Opnd
(N
))
2374 and then Scope
(Base_Type
(Etype
(Left_Opnd
(N
)))) /=
2377 Err_Type
:= First_Subtype
(Etype
(Left_Opnd
(N
)));
2379 if Comes_From_Source
(Err_Type
)
2380 and then Present
(Parent
(Err_Type
))
2382 Error_Msg_Sloc
:= Sloc
(Parent
(Err_Type
));
2385 -- If this is an indirect call, use the subprogram_type
2386 -- in the message, to have a meaningful location. Also
2387 -- indicate if this is an inherited operation, created
2388 -- by a type declaration.
2390 elsif Nkind
(N
) = N_Function_Call
2391 and then Nkind
(Name
(N
)) = N_Explicit_Dereference
2392 and then Is_Type
(It
.Nam
)
2396 Sloc
(Associated_Node_For_Itype
(Err_Type
));
2401 if Nkind
(N
) in N_Op
2402 and then Scope
(It
.Nam
) = Standard_Standard
2403 and then Present
(Err_Type
)
2405 -- Special-case the message for universal_fixed
2406 -- operators, which are not declared with the type
2407 -- of the operand, but appear forever in Standard.
2409 if It
.Typ
= Universal_Fixed
2410 and then Scope
(It
.Nam
) = Standard_Standard
2413 ("\\possible interpretation as universal_fixed "
2414 & "operation (RM 4.5.5 (19))", N
);
2417 ("\\possible interpretation (predefined)#!", N
);
2421 Nkind
(Parent
(It
.Nam
)) = N_Full_Type_Declaration
2424 ("\\possible interpretation (inherited)#!", N
);
2426 Error_Msg_N
-- CODEFIX
2427 ("\\possible interpretation#!", N
);
2433 -- We have a matching interpretation, Expr_Type is the type
2434 -- from this interpretation, and Seen is the entity.
2436 -- For an operator, just set the entity name. The type will be
2437 -- set by the specific operator resolution routine.
2439 if Nkind
(N
) in N_Op
then
2440 Set_Entity
(N
, Seen
);
2441 Generate_Reference
(Seen
, N
);
2443 elsif Nkind_In
(N
, N_Case_Expression
,
2444 N_Character_Literal
,
2448 Set_Etype
(N
, Expr_Type
);
2450 -- AI05-0139-2: Expression is overloaded because type has
2451 -- implicit dereference. If type matches context, no implicit
2452 -- dereference is involved. If the expression is an entity,
2453 -- generate a reference to it, as this is not done for an
2454 -- overloaded construct during analysis.
2456 elsif Has_Implicit_Dereference
(Expr_Type
) then
2457 Set_Etype
(N
, Expr_Type
);
2458 Set_Is_Overloaded
(N
, False);
2460 if Is_Entity_Name
(N
) then
2461 Generate_Reference
(Entity
(N
), N
);
2466 elsif Is_Overloaded
(N
)
2467 and then Present
(It
.Nam
)
2468 and then Ekind
(It
.Nam
) = E_Discriminant
2469 and then Has_Implicit_Dereference
(It
.Nam
)
2471 -- If the node is a general indexing, the dereference is
2472 -- is inserted when resolving the rewritten form, else
2475 if Nkind
(N
) /= N_Indexed_Component
2476 or else No
(Generalized_Indexing
(N
))
2478 Build_Explicit_Dereference
(N
, It
.Nam
);
2481 -- For an explicit dereference, attribute reference, range,
2482 -- short-circuit form (which is not an operator node), or call
2483 -- with a name that is an explicit dereference, there is
2484 -- nothing to be done at this point.
2486 elsif Nkind_In
(N
, N_Attribute_Reference
,
2488 N_Explicit_Dereference
,
2490 N_Indexed_Component
,
2493 N_Selected_Component
,
2495 or else Nkind
(Name
(N
)) = N_Explicit_Dereference
2499 -- For procedure or function calls, set the type of the name,
2500 -- and also the entity pointer for the prefix.
2502 elsif Nkind
(N
) in N_Subprogram_Call
2503 and then Is_Entity_Name
(Name
(N
))
2505 Set_Etype
(Name
(N
), Expr_Type
);
2506 Set_Entity
(Name
(N
), Seen
);
2507 Generate_Reference
(Seen
, Name
(N
));
2509 elsif Nkind
(N
) = N_Function_Call
2510 and then Nkind
(Name
(N
)) = N_Selected_Component
2512 Set_Etype
(Name
(N
), Expr_Type
);
2513 Set_Entity
(Selector_Name
(Name
(N
)), Seen
);
2514 Generate_Reference
(Seen
, Selector_Name
(Name
(N
)));
2516 -- For all other cases, just set the type of the Name
2519 Set_Etype
(Name
(N
), Expr_Type
);
2526 -- Move to next interpretation
2528 exit Interp_Loop
when No
(It
.Typ
);
2530 Get_Next_Interp
(I
, It
);
2531 end loop Interp_Loop
;
2534 -- At this stage Found indicates whether or not an acceptable
2535 -- interpretation exists. If not, then we have an error, except that if
2536 -- the context is Any_Type as a result of some other error, then we
2537 -- suppress the error report.
2540 if Typ
/= Any_Type
then
2542 -- If type we are looking for is Void, then this is the procedure
2543 -- call case, and the error is simply that what we gave is not a
2544 -- procedure name (we think of procedure calls as expressions with
2545 -- types internally, but the user doesn't think of them this way).
2547 if Typ
= Standard_Void_Type
then
2549 -- Special case message if function used as a procedure
2551 if Nkind
(N
) = N_Procedure_Call_Statement
2552 and then Is_Entity_Name
(Name
(N
))
2553 and then Ekind
(Entity
(Name
(N
))) = E_Function
2556 ("cannot use call to function & as a statement",
2557 Name
(N
), Entity
(Name
(N
)));
2559 ("\return value of a function call cannot be ignored",
2562 -- Otherwise give general message (not clear what cases this
2563 -- covers, but no harm in providing for them).
2566 Error_Msg_N
("expect procedure name in procedure call", N
);
2571 -- Otherwise we do have a subexpression with the wrong type
2573 -- Check for the case of an allocator which uses an access type
2574 -- instead of the designated type. This is a common error and we
2575 -- specialize the message, posting an error on the operand of the
2576 -- allocator, complaining that we expected the designated type of
2579 elsif Nkind
(N
) = N_Allocator
2580 and then Is_Access_Type
(Typ
)
2581 and then Is_Access_Type
(Etype
(N
))
2582 and then Designated_Type
(Etype
(N
)) = Typ
2584 Wrong_Type
(Expression
(N
), Designated_Type
(Typ
));
2587 -- Check for view mismatch on Null in instances, for which the
2588 -- view-swapping mechanism has no identifier.
2590 elsif (In_Instance
or else In_Inlined_Body
)
2591 and then (Nkind
(N
) = N_Null
)
2592 and then Is_Private_Type
(Typ
)
2593 and then Is_Access_Type
(Full_View
(Typ
))
2595 Resolve
(N
, Full_View
(Typ
));
2599 -- Check for an aggregate. Sometimes we can get bogus aggregates
2600 -- from misuse of parentheses, and we are about to complain about
2601 -- the aggregate without even looking inside it.
2603 -- Instead, if we have an aggregate of type Any_Composite, then
2604 -- analyze and resolve the component fields, and then only issue
2605 -- another message if we get no errors doing this (otherwise
2606 -- assume that the errors in the aggregate caused the problem).
2608 elsif Nkind
(N
) = N_Aggregate
2609 and then Etype
(N
) = Any_Composite
2611 -- Disable expansion in any case. If there is a type mismatch
2612 -- it may be fatal to try to expand the aggregate. The flag
2613 -- would otherwise be set to false when the error is posted.
2615 Expander_Active
:= False;
2618 procedure Check_Aggr
(Aggr
: Node_Id
);
2619 -- Check one aggregate, and set Found to True if we have a
2620 -- definite error in any of its elements
2622 procedure Check_Elmt
(Aelmt
: Node_Id
);
2623 -- Check one element of aggregate and set Found to True if
2624 -- we definitely have an error in the element.
2630 procedure Check_Aggr
(Aggr
: Node_Id
) is
2634 if Present
(Expressions
(Aggr
)) then
2635 Elmt
:= First
(Expressions
(Aggr
));
2636 while Present
(Elmt
) loop
2642 if Present
(Component_Associations
(Aggr
)) then
2643 Elmt
:= First
(Component_Associations
(Aggr
));
2644 while Present
(Elmt
) loop
2646 -- If this is a default-initialized component, then
2647 -- there is nothing to check. The box will be
2648 -- replaced by the appropriate call during late
2651 if Nkind
(Elmt
) /= N_Iterated_Component_Association
2652 and then not Box_Present
(Elmt
)
2654 Check_Elmt
(Expression
(Elmt
));
2666 procedure Check_Elmt
(Aelmt
: Node_Id
) is
2668 -- If we have a nested aggregate, go inside it (to
2669 -- attempt a naked analyze-resolve of the aggregate can
2670 -- cause undesirable cascaded errors). Do not resolve
2671 -- expression if it needs a type from context, as for
2672 -- integer * fixed expression.
2674 if Nkind
(Aelmt
) = N_Aggregate
then
2680 if not Is_Overloaded
(Aelmt
)
2681 and then Etype
(Aelmt
) /= Any_Fixed
2686 if Etype
(Aelmt
) = Any_Type
then
2697 -- Looks like we have a type error, but check for special case
2698 -- of Address wanted, integer found, with the configuration pragma
2699 -- Allow_Integer_Address active. If we have this case, introduce
2700 -- an unchecked conversion to allow the integer expression to be
2701 -- treated as an Address. The reverse case of integer wanted,
2702 -- Address found, is treated in an analogous manner.
2704 if Address_Integer_Convert_OK
(Typ
, Etype
(N
)) then
2705 Rewrite
(N
, Unchecked_Convert_To
(Typ
, Relocate_Node
(N
)));
2706 Analyze_And_Resolve
(N
, Typ
);
2709 -- Under relaxed RM semantics silently replace occurrences of null
2710 -- by System.Address_Null.
2712 elsif Null_To_Null_Address_Convert_OK
(N
, Typ
) then
2713 Replace_Null_By_Null_Address
(N
);
2714 Analyze_And_Resolve
(N
, Typ
);
2718 -- That special Allow_Integer_Address check did not apply, so we
2719 -- have a real type error. If an error message was issued already,
2720 -- Found got reset to True, so if it's still False, issue standard
2721 -- Wrong_Type message.
2724 if Is_Overloaded
(N
) and then Nkind
(N
) = N_Function_Call
then
2726 Subp_Name
: Node_Id
;
2729 if Is_Entity_Name
(Name
(N
)) then
2730 Subp_Name
:= Name
(N
);
2732 elsif Nkind
(Name
(N
)) = N_Selected_Component
then
2734 -- Protected operation: retrieve operation name
2736 Subp_Name
:= Selector_Name
(Name
(N
));
2739 raise Program_Error
;
2742 Error_Msg_Node_2
:= Typ
;
2744 ("no visible interpretation of& matches expected type&",
2748 if All_Errors_Mode
then
2750 Index
: Interp_Index
;
2754 Error_Msg_N
("\\possible interpretations:", N
);
2756 Get_First_Interp
(Name
(N
), Index
, It
);
2757 while Present
(It
.Nam
) loop
2758 Error_Msg_Sloc
:= Sloc
(It
.Nam
);
2759 Error_Msg_Node_2
:= It
.Nam
;
2761 ("\\ type& for & declared#", N
, It
.Typ
);
2762 Get_Next_Interp
(Index
, It
);
2767 Error_Msg_N
("\use -gnatf for details", N
);
2771 Wrong_Type
(N
, Typ
);
2779 -- Test if we have more than one interpretation for the context
2781 elsif Ambiguous
then
2785 -- Only one intepretation
2788 -- In Ada 2005, if we have something like "X : T := 2 + 2;", where
2789 -- the "+" on T is abstract, and the operands are of universal type,
2790 -- the above code will have (incorrectly) resolved the "+" to the
2791 -- universal one in Standard. Therefore check for this case and give
2792 -- an error. We can't do this earlier, because it would cause legal
2793 -- cases to get errors (when some other type has an abstract "+").
2795 if Ada_Version
>= Ada_2005
2796 and then Nkind
(N
) in N_Op
2797 and then Is_Overloaded
(N
)
2798 and then Is_Universal_Numeric_Type
(Etype
(Entity
(N
)))
2800 Get_First_Interp
(N
, I
, It
);
2801 while Present
(It
.Typ
) loop
2802 if Present
(It
.Abstract_Op
) and then
2803 Etype
(It
.Abstract_Op
) = Typ
2806 ("cannot call abstract subprogram &!", N
, It
.Abstract_Op
);
2810 Get_Next_Interp
(I
, It
);
2814 -- Here we have an acceptable interpretation for the context
2816 -- Propagate type information and normalize tree for various
2817 -- predefined operations. If the context only imposes a class of
2818 -- types, rather than a specific type, propagate the actual type
2821 if Typ
= Any_Integer
or else
2822 Typ
= Any_Boolean
or else
2823 Typ
= Any_Modular
or else
2824 Typ
= Any_Real
or else
2827 Ctx_Type
:= Expr_Type
;
2829 -- Any_Fixed is legal in a real context only if a specific fixed-
2830 -- point type is imposed. If Norman Cohen can be confused by this,
2831 -- it deserves a separate message.
2834 and then Expr_Type
= Any_Fixed
2836 Error_Msg_N
("illegal context for mixed mode operation", N
);
2837 Set_Etype
(N
, Universal_Real
);
2838 Ctx_Type
:= Universal_Real
;
2842 -- A user-defined operator is transformed into a function call at
2843 -- this point, so that further processing knows that operators are
2844 -- really operators (i.e. are predefined operators). User-defined
2845 -- operators that are intrinsic are just renamings of the predefined
2846 -- ones, and need not be turned into calls either, but if they rename
2847 -- a different operator, we must transform the node accordingly.
2848 -- Instantiations of Unchecked_Conversion are intrinsic but are
2849 -- treated as functions, even if given an operator designator.
2851 if Nkind
(N
) in N_Op
2852 and then Present
(Entity
(N
))
2853 and then Ekind
(Entity
(N
)) /= E_Operator
2855 if not Is_Predefined_Op
(Entity
(N
)) then
2856 Rewrite_Operator_As_Call
(N
, Entity
(N
));
2858 elsif Present
(Alias
(Entity
(N
)))
2860 Nkind
(Parent
(Parent
(Entity
(N
)))) =
2861 N_Subprogram_Renaming_Declaration
2863 Rewrite_Renamed_Operator
(N
, Alias
(Entity
(N
)), Typ
);
2865 -- If the node is rewritten, it will be fully resolved in
2866 -- Rewrite_Renamed_Operator.
2868 if Analyzed
(N
) then
2874 case N_Subexpr
'(Nkind (N)) is
2876 Resolve_Aggregate (N, Ctx_Type);
2879 Resolve_Allocator (N, Ctx_Type);
2881 when N_Short_Circuit =>
2882 Resolve_Short_Circuit (N, Ctx_Type);
2884 when N_Attribute_Reference =>
2885 Resolve_Attribute (N, Ctx_Type);
2887 when N_Case_Expression =>
2888 Resolve_Case_Expression (N, Ctx_Type);
2890 when N_Character_Literal =>
2891 Resolve_Character_Literal (N, Ctx_Type);
2893 when N_Delta_Aggregate =>
2894 Resolve_Delta_Aggregate (N, Ctx_Type);
2896 when N_Expanded_Name =>
2897 Resolve_Entity_Name (N, Ctx_Type);
2899 when N_Explicit_Dereference =>
2900 Resolve_Explicit_Dereference (N, Ctx_Type);
2902 when N_Expression_With_Actions =>
2903 Resolve_Expression_With_Actions (N, Ctx_Type);
2905 when N_Extension_Aggregate =>
2906 Resolve_Extension_Aggregate (N, Ctx_Type);
2908 when N_Function_Call =>
2909 Resolve_Call (N, Ctx_Type);
2911 when N_Identifier =>
2912 Resolve_Entity_Name (N, Ctx_Type);
2914 when N_If_Expression =>
2915 Resolve_If_Expression (N, Ctx_Type);
2917 when N_Indexed_Component =>
2918 Resolve_Indexed_Component (N, Ctx_Type);
2920 when N_Integer_Literal =>
2921 Resolve_Integer_Literal (N, Ctx_Type);
2923 when N_Membership_Test =>
2924 Resolve_Membership_Op (N, Ctx_Type);
2927 Resolve_Null (N, Ctx_Type);
2933 Resolve_Logical_Op (N, Ctx_Type);
2938 Resolve_Equality_Op (N, Ctx_Type);
2945 Resolve_Comparison_Op (N, Ctx_Type);
2948 Resolve_Op_Not (N, Ctx_Type);
2957 Resolve_Arithmetic_Op (N, Ctx_Type);
2960 Resolve_Op_Concat (N, Ctx_Type);
2963 Resolve_Op_Expon (N, Ctx_Type);
2969 Resolve_Unary_Op (N, Ctx_Type);
2972 Resolve_Shift (N, Ctx_Type);
2974 when N_Procedure_Call_Statement =>
2975 Resolve_Call (N, Ctx_Type);
2977 when N_Operator_Symbol =>
2978 Resolve_Operator_Symbol (N, Ctx_Type);
2980 when N_Qualified_Expression =>
2981 Resolve_Qualified_Expression (N, Ctx_Type);
2983 -- Why is the following null, needs a comment ???
2985 when N_Quantified_Expression =>
2988 when N_Raise_Expression =>
2989 Resolve_Raise_Expression (N, Ctx_Type);
2991 when N_Raise_xxx_Error =>
2992 Set_Etype (N, Ctx_Type);
2995 Resolve_Range (N, Ctx_Type);
2997 when N_Real_Literal =>
2998 Resolve_Real_Literal (N, Ctx_Type);
3001 Resolve_Reference (N, Ctx_Type);
3003 when N_Selected_Component =>
3004 Resolve_Selected_Component (N, Ctx_Type);
3007 Resolve_Slice (N, Ctx_Type);
3009 when N_String_Literal =>
3010 Resolve_String_Literal (N, Ctx_Type);
3012 when N_Target_Name =>
3013 Resolve_Target_Name (N, Ctx_Type);
3015 when N_Type_Conversion =>
3016 Resolve_Type_Conversion (N, Ctx_Type);
3018 when N_Unchecked_Expression =>
3019 Resolve_Unchecked_Expression (N, Ctx_Type);
3021 when N_Unchecked_Type_Conversion =>
3022 Resolve_Unchecked_Type_Conversion (N, Ctx_Type);
3025 -- Mark relevant use-type and use-package clauses as effective using
3026 -- the original node because constant folding may have occured and
3027 -- removed references that need to be examined.
3029 if Nkind (Original_Node (N)) in N_Op then
3030 Mark_Use_Clauses (Original_Node (N));
3033 -- Ada 2012 (AI05-0149): Apply an (implicit) conversion to an
3034 -- expression of an anonymous access type that occurs in the context
3035 -- of a named general access type, except when the expression is that
3036 -- of a membership test. This ensures proper legality checking in
3037 -- terms of allowed conversions (expressions that would be illegal to
3038 -- convert implicitly are allowed in membership tests).
3040 if Ada_Version >= Ada_2012
3041 and then Ekind (Ctx_Type) = E_General_Access_Type
3042 and then Ekind (Etype (N)) = E_Anonymous_Access_Type
3043 and then Nkind (Parent (N)) not in N_Membership_Test
3045 Rewrite (N, Convert_To (Ctx_Type, Relocate_Node (N)));
3046 Analyze_And_Resolve (N, Ctx_Type);
3049 -- If the subexpression was replaced by a non-subexpression, then
3050 -- all we do is to expand it. The only legitimate case we know of
3051 -- is converting procedure call statement to entry call statements,
3052 -- but there may be others, so we are making this test general.
3054 if Nkind (N) not in N_Subexpr then
3055 Debug_A_Exit ("resolving ", N, " (done)");
3060 -- The expression is definitely NOT overloaded at this point, so
3061 -- we reset the Is_Overloaded flag to avoid any confusion when
3062 -- reanalyzing the node.
3064 Set_Is_Overloaded (N, False);
3066 -- Freeze expression type, entity if it is a name, and designated
3067 -- type if it is an allocator (RM 13.14(10,11,13)).
3069 -- Now that the resolution of the type of the node is complete, and
3070 -- we did not detect an error, we can expand this node. We skip the
3071 -- expand call if we are in a default expression, see section
3072 -- "Handling of Default Expressions" in Sem spec.
3074 Debug_A_Exit ("resolving ", N, " (done)");
3076 -- We unconditionally freeze the expression, even if we are in
3077 -- default expression mode (the Freeze_Expression routine tests this
3078 -- flag and only freezes static types if it is set).
3080 -- Ada 2012 (AI05-177): The declaration of an expression function
3081 -- does not cause freezing, but we never reach here in that case.
3082 -- Here we are resolving the corresponding expanded body, so we do
3083 -- need to perform normal freezing.
3085 -- As elsewhere we do not emit freeze node within a generic. We make
3086 -- an exception for entities that are expressions, only to detect
3087 -- misuses of deferred constants and preserve the output of various
3090 if not Inside_A_Generic or else Is_Entity_Name (N) then
3091 Freeze_Expression (N);
3094 -- Now we can do the expansion
3104 -- Version with check(s) suppressed
3106 procedure Resolve (N : Node_Id; Typ : Entity_Id; Suppress : Check_Id) is
3108 if Suppress = All_Checks then
3110 Sva : constant Suppress_Array := Scope_Suppress.Suppress;
3112 Scope_Suppress.Suppress := (others => True);
3114 Scope_Suppress.Suppress := Sva;
3119 Svg : constant Boolean := Scope_Suppress.Suppress (Suppress);
3121 Scope_Suppress.Suppress (Suppress) := True;
3123 Scope_Suppress.Suppress (Suppress) := Svg;
3132 -- Version with implicit type
3134 procedure Resolve (N : Node_Id) is
3136 Resolve (N, Etype (N));
3139 ---------------------
3140 -- Resolve_Actuals --
3141 ---------------------
3143 procedure Resolve_Actuals (N : Node_Id; Nam : Entity_Id) is
3144 Loc : constant Source_Ptr := Sloc (N);
3147 A_Typ : Entity_Id := Empty; -- init to avoid warning
3150 Prev : Node_Id := Empty;
3152 Real_F : Entity_Id := Empty; -- init to avoid warning
3154 Real_Subp : Entity_Id;
3155 -- If the subprogram being called is an inherited operation for
3156 -- a formal derived type in an instance, Real_Subp is the subprogram
3157 -- that will be called. It may have different formal names than the
3158 -- operation of the formal in the generic, so after actual is resolved
3159 -- the name of the actual in a named association must carry the name
3160 -- of the actual of the subprogram being called.
3162 procedure Check_Aliased_Parameter;
3163 -- Check rules on aliased parameters and related accessibility rules
3164 -- in (RM 3.10.2 (10.2-10.4)).
3166 procedure Check_Argument_Order;
3167 -- Performs a check for the case where the actuals are all simple
3168 -- identifiers that correspond to the formal names, but in the wrong
3169 -- order, which is considered suspicious and cause for a warning.
3171 procedure Check_Prefixed_Call;
3172 -- If the original node is an overloaded call in prefix notation,
3173 -- insert an 'Access or a dereference as needed over the first actual
.
3174 -- Try_Object_Operation has already verified that there is a valid
3175 -- interpretation, but the form of the actual can only be determined
3176 -- once the primitive operation is identified.
3178 procedure Flag_Effectively_Volatile_Objects
(Expr
: Node_Id
);
3179 -- Emit an error concerning the illegal usage of an effectively volatile
3180 -- object in interfering context (SPARK RM 7.13(12)).
3182 procedure Insert_Default
;
3183 -- If the actual is missing in a call, insert in the actuals list
3184 -- an instance of the default expression. The insertion is always
3185 -- a named association.
3187 function Same_Ancestor
(T1
, T2
: Entity_Id
) return Boolean;
3188 -- Check whether T1 and T2, or their full views, are derived from a
3189 -- common type. Used to enforce the restrictions on array conversions
3192 function Static_Concatenation
(N
: Node_Id
) return Boolean;
3193 -- Predicate to determine whether an actual that is a concatenation
3194 -- will be evaluated statically and does not need a transient scope.
3195 -- This must be determined before the actual is resolved and expanded
3196 -- because if needed the transient scope must be introduced earlier.
3198 -----------------------------
3199 -- Check_Aliased_Parameter --
3200 -----------------------------
3202 procedure Check_Aliased_Parameter
is
3203 Nominal_Subt
: Entity_Id
;
3206 if Is_Aliased
(F
) then
3207 if Is_Tagged_Type
(A_Typ
) then
3210 elsif Is_Aliased_View
(A
) then
3211 if Is_Constr_Subt_For_U_Nominal
(A_Typ
) then
3212 Nominal_Subt
:= Base_Type
(A_Typ
);
3214 Nominal_Subt
:= A_Typ
;
3217 if Subtypes_Statically_Match
(F_Typ
, Nominal_Subt
) then
3220 -- In a generic body assume the worst for generic formals:
3221 -- they can have a constrained partial view (AI05-041).
3223 elsif Has_Discriminants
(F_Typ
)
3224 and then not Is_Constrained
(F_Typ
)
3225 and then not Has_Constrained_Partial_View
(F_Typ
)
3226 and then not Is_Generic_Type
(F_Typ
)
3231 Error_Msg_NE
("untagged actual does not match "
3232 & "aliased formal&", A
, F
);
3236 Error_Msg_NE
("actual for aliased formal& must be "
3237 & "aliased object", A
, F
);
3240 if Ekind
(Nam
) = E_Procedure
then
3243 elsif Ekind
(Etype
(Nam
)) = E_Anonymous_Access_Type
then
3244 if Nkind
(Parent
(N
)) = N_Type_Conversion
3245 and then Type_Access_Level
(Etype
(Parent
(N
))) <
3246 Object_Access_Level
(A
)
3248 Error_Msg_N
("aliased actual has wrong accessibility", A
);
3251 elsif Nkind
(Parent
(N
)) = N_Qualified_Expression
3252 and then Nkind
(Parent
(Parent
(N
))) = N_Allocator
3253 and then Type_Access_Level
(Etype
(Parent
(Parent
(N
)))) <
3254 Object_Access_Level
(A
)
3257 ("aliased actual in allocator has wrong accessibility", A
);
3260 end Check_Aliased_Parameter
;
3262 --------------------------
3263 -- Check_Argument_Order --
3264 --------------------------
3266 procedure Check_Argument_Order
is
3268 -- Nothing to do if no parameters, or original node is neither a
3269 -- function call nor a procedure call statement (happens in the
3270 -- operator-transformed-to-function call case), or the call does
3271 -- not come from source, or this warning is off.
3273 if not Warn_On_Parameter_Order
3274 or else No
(Parameter_Associations
(N
))
3275 or else Nkind
(Original_Node
(N
)) not in N_Subprogram_Call
3276 or else not Comes_From_Source
(N
)
3282 Nargs
: constant Nat
:= List_Length
(Parameter_Associations
(N
));
3285 -- Nothing to do if only one parameter
3291 -- Here if at least two arguments
3294 Actuals
: array (1 .. Nargs
) of Node_Id
;
3298 Wrong_Order
: Boolean := False;
3299 -- Set True if an out of order case is found
3302 -- Collect identifier names of actuals, fail if any actual is
3303 -- not a simple identifier, and record max length of name.
3305 Actual
:= First
(Parameter_Associations
(N
));
3306 for J
in Actuals
'Range loop
3307 if Nkind
(Actual
) /= N_Identifier
then
3310 Actuals
(J
) := Actual
;
3315 -- If we got this far, all actuals are identifiers and the list
3316 -- of their names is stored in the Actuals array.
3318 Formal
:= First_Formal
(Nam
);
3319 for J
in Actuals
'Range loop
3321 -- If we ran out of formals, that's odd, probably an error
3322 -- which will be detected elsewhere, but abandon the search.
3328 -- If name matches and is in order OK
3330 if Chars
(Formal
) = Chars
(Actuals
(J
)) then
3334 -- If no match, see if it is elsewhere in list and if so
3335 -- flag potential wrong order if type is compatible.
3337 for K
in Actuals
'Range loop
3338 if Chars
(Formal
) = Chars
(Actuals
(K
))
3340 Has_Compatible_Type
(Actuals
(K
), Etype
(Formal
))
3342 Wrong_Order
:= True;
3352 <<Continue
>> Next_Formal
(Formal
);
3355 -- If Formals left over, also probably an error, skip warning
3357 if Present
(Formal
) then
3361 -- Here we give the warning if something was out of order
3365 ("?P?actuals for this call may be in wrong order", N
);
3369 end Check_Argument_Order
;
3371 -------------------------
3372 -- Check_Prefixed_Call --
3373 -------------------------
3375 procedure Check_Prefixed_Call
is
3376 Act
: constant Node_Id
:= First_Actual
(N
);
3377 A_Type
: constant Entity_Id
:= Etype
(Act
);
3378 F_Type
: constant Entity_Id
:= Etype
(First_Formal
(Nam
));
3379 Orig
: constant Node_Id
:= Original_Node
(N
);
3383 -- Check whether the call is a prefixed call, with or without
3384 -- additional actuals.
3386 if Nkind
(Orig
) = N_Selected_Component
3388 (Nkind
(Orig
) = N_Indexed_Component
3389 and then Nkind
(Prefix
(Orig
)) = N_Selected_Component
3390 and then Is_Entity_Name
(Prefix
(Prefix
(Orig
)))
3391 and then Is_Entity_Name
(Act
)
3392 and then Chars
(Act
) = Chars
(Prefix
(Prefix
(Orig
))))
3394 if Is_Access_Type
(A_Type
)
3395 and then not Is_Access_Type
(F_Type
)
3397 -- Introduce dereference on object in prefix
3400 Make_Explicit_Dereference
(Sloc
(Act
),
3401 Prefix
=> Relocate_Node
(Act
));
3402 Rewrite
(Act
, New_A
);
3405 elsif Is_Access_Type
(F_Type
)
3406 and then not Is_Access_Type
(A_Type
)
3408 -- Introduce an implicit 'Access in prefix
3410 if not Is_Aliased_View
(Act
) then
3412 ("object in prefixed call to& must be aliased "
3413 & "(RM 4.1.3 (13 1/2))",
3418 Make_Attribute_Reference
(Loc
,
3419 Attribute_Name
=> Name_Access
,
3420 Prefix
=> Relocate_Node
(Act
)));
3425 end Check_Prefixed_Call
;
3427 ---------------------------------------
3428 -- Flag_Effectively_Volatile_Objects --
3429 ---------------------------------------
3431 procedure Flag_Effectively_Volatile_Objects
(Expr
: Node_Id
) is
3432 function Flag_Object
(N
: Node_Id
) return Traverse_Result
;
3433 -- Determine whether arbitrary node N denotes an effectively volatile
3434 -- object and if it does, emit an error.
3440 function Flag_Object
(N
: Node_Id
) return Traverse_Result
is
3444 -- Do not consider nested function calls because they have already
3445 -- been processed during their own resolution.
3447 if Nkind
(N
) = N_Function_Call
then
3450 elsif Is_Entity_Name
(N
) and then Present
(Entity
(N
)) then
3454 and then Is_Effectively_Volatile
(Id
)
3455 and then (Async_Writers_Enabled
(Id
)
3456 or else Effective_Reads_Enabled
(Id
))
3459 ("volatile object cannot appear in this context (SPARK "
3460 & "RM 7.1.3(11))", N
);
3468 procedure Flag_Objects
is new Traverse_Proc
(Flag_Object
);
3470 -- Start of processing for Flag_Effectively_Volatile_Objects
3473 Flag_Objects
(Expr
);
3474 end Flag_Effectively_Volatile_Objects
;
3476 --------------------
3477 -- Insert_Default --
3478 --------------------
3480 procedure Insert_Default
is
3485 -- Missing argument in call, nothing to insert
3487 if No
(Default_Value
(F
)) then
3491 -- Note that we do a full New_Copy_Tree, so that any associated
3492 -- Itypes are properly copied. This may not be needed any more,
3493 -- but it does no harm as a safety measure. Defaults of a generic
3494 -- formal may be out of bounds of the corresponding actual (see
3495 -- cc1311b) and an additional check may be required.
3500 New_Scope
=> Current_Scope
,
3503 -- Propagate dimension information, if any.
3505 Copy_Dimensions
(Default_Value
(F
), Actval
);
3507 if Is_Concurrent_Type
(Scope
(Nam
))
3508 and then Has_Discriminants
(Scope
(Nam
))
3510 Replace_Actual_Discriminants
(N
, Actval
);
3513 if Is_Overloadable
(Nam
)
3514 and then Present
(Alias
(Nam
))
3516 if Base_Type
(Etype
(F
)) /= Base_Type
(Etype
(Actval
))
3517 and then not Is_Tagged_Type
(Etype
(F
))
3519 -- If default is a real literal, do not introduce a
3520 -- conversion whose effect may depend on the run-time
3521 -- size of universal real.
3523 if Nkind
(Actval
) = N_Real_Literal
then
3524 Set_Etype
(Actval
, Base_Type
(Etype
(F
)));
3526 Actval
:= Unchecked_Convert_To
(Etype
(F
), Actval
);
3530 if Is_Scalar_Type
(Etype
(F
)) then
3531 Enable_Range_Check
(Actval
);
3534 Set_Parent
(Actval
, N
);
3536 -- Resolve aggregates with their base type, to avoid scope
3537 -- anomalies: the subtype was first built in the subprogram
3538 -- declaration, and the current call may be nested.
3540 if Nkind
(Actval
) = N_Aggregate
then
3541 Analyze_And_Resolve
(Actval
, Etype
(F
));
3543 Analyze_And_Resolve
(Actval
, Etype
(Actval
));
3547 Set_Parent
(Actval
, N
);
3549 -- See note above concerning aggregates
3551 if Nkind
(Actval
) = N_Aggregate
3552 and then Has_Discriminants
(Etype
(Actval
))
3554 Analyze_And_Resolve
(Actval
, Base_Type
(Etype
(Actval
)));
3556 -- Resolve entities with their own type, which may differ from
3557 -- the type of a reference in a generic context (the view
3558 -- swapping mechanism did not anticipate the re-analysis of
3559 -- default values in calls).
3561 elsif Is_Entity_Name
(Actval
) then
3562 Analyze_And_Resolve
(Actval
, Etype
(Entity
(Actval
)));
3565 Analyze_And_Resolve
(Actval
, Etype
(Actval
));
3569 -- If default is a tag indeterminate function call, propagate tag
3570 -- to obtain proper dispatching.
3572 if Is_Controlling_Formal
(F
)
3573 and then Nkind
(Default_Value
(F
)) = N_Function_Call
3575 Set_Is_Controlling_Actual
(Actval
);
3579 -- If the default expression raises constraint error, then just
3580 -- silently replace it with an N_Raise_Constraint_Error node, since
3581 -- we already gave the warning on the subprogram spec. If node is
3582 -- already a Raise_Constraint_Error leave as is, to prevent loops in
3583 -- the warnings removal machinery.
3585 if Raises_Constraint_Error
(Actval
)
3586 and then Nkind
(Actval
) /= N_Raise_Constraint_Error
3589 Make_Raise_Constraint_Error
(Loc
,
3590 Reason
=> CE_Range_Check_Failed
));
3592 Set_Raises_Constraint_Error
(Actval
);
3593 Set_Etype
(Actval
, Etype
(F
));
3597 Make_Parameter_Association
(Loc
,
3598 Explicit_Actual_Parameter
=> Actval
,
3599 Selector_Name
=> Make_Identifier
(Loc
, Chars
(F
)));
3601 -- Case of insertion is first named actual
3604 or else Nkind
(Parent
(Prev
)) /= N_Parameter_Association
3606 Set_Next_Named_Actual
(Assoc
, First_Named_Actual
(N
));
3607 Set_First_Named_Actual
(N
, Actval
);
3610 if No
(Parameter_Associations
(N
)) then
3611 Set_Parameter_Associations
(N
, New_List
(Assoc
));
3613 Append
(Assoc
, Parameter_Associations
(N
));
3617 Insert_After
(Prev
, Assoc
);
3620 -- Case of insertion is not first named actual
3623 Set_Next_Named_Actual
3624 (Assoc
, Next_Named_Actual
(Parent
(Prev
)));
3625 Set_Next_Named_Actual
(Parent
(Prev
), Actval
);
3626 Append
(Assoc
, Parameter_Associations
(N
));
3629 Mark_Rewrite_Insertion
(Assoc
);
3630 Mark_Rewrite_Insertion
(Actval
);
3639 function Same_Ancestor
(T1
, T2
: Entity_Id
) return Boolean is
3640 FT1
: Entity_Id
:= T1
;
3641 FT2
: Entity_Id
:= T2
;
3644 if Is_Private_Type
(T1
)
3645 and then Present
(Full_View
(T1
))
3647 FT1
:= Full_View
(T1
);
3650 if Is_Private_Type
(T2
)
3651 and then Present
(Full_View
(T2
))
3653 FT2
:= Full_View
(T2
);
3656 return Root_Type
(Base_Type
(FT1
)) = Root_Type
(Base_Type
(FT2
));
3659 --------------------------
3660 -- Static_Concatenation --
3661 --------------------------
3663 function Static_Concatenation
(N
: Node_Id
) return Boolean is
3666 when N_String_Literal
=>
3671 -- Concatenation is static when both operands are static and
3672 -- the concatenation operator is a predefined one.
3674 return Scope
(Entity
(N
)) = Standard_Standard
3676 Static_Concatenation
(Left_Opnd
(N
))
3678 Static_Concatenation
(Right_Opnd
(N
));
3681 if Is_Entity_Name
(N
) then
3683 Ent
: constant Entity_Id
:= Entity
(N
);
3685 return Ekind
(Ent
) = E_Constant
3686 and then Present
(Constant_Value
(Ent
))
3688 Is_OK_Static_Expression
(Constant_Value
(Ent
));
3695 end Static_Concatenation
;
3697 -- Start of processing for Resolve_Actuals
3700 Check_Argument_Order
;
3702 if Is_Overloadable
(Nam
)
3703 and then Is_Inherited_Operation
(Nam
)
3704 and then In_Instance
3705 and then Present
(Alias
(Nam
))
3706 and then Present
(Overridden_Operation
(Alias
(Nam
)))
3708 Real_Subp
:= Alias
(Nam
);
3713 if Present
(First_Actual
(N
)) then
3714 Check_Prefixed_Call
;
3717 A
:= First_Actual
(N
);
3718 F
:= First_Formal
(Nam
);
3720 if Present
(Real_Subp
) then
3721 Real_F
:= First_Formal
(Real_Subp
);
3724 while Present
(F
) loop
3725 if No
(A
) and then Needs_No_Actuals
(Nam
) then
3728 -- If we have an error in any actual or formal, indicated by a type
3729 -- of Any_Type, then abandon resolution attempt, and set result type
3730 -- to Any_Type. Skip this if the actual is a Raise_Expression, whose
3731 -- type is imposed from context.
3733 elsif (Present
(A
) and then Etype
(A
) = Any_Type
)
3734 or else Etype
(F
) = Any_Type
3736 if Nkind
(A
) /= N_Raise_Expression
then
3737 Set_Etype
(N
, Any_Type
);
3742 -- Case where actual is present
3744 -- If the actual is an entity, generate a reference to it now. We
3745 -- do this before the actual is resolved, because a formal of some
3746 -- protected subprogram, or a task discriminant, will be rewritten
3747 -- during expansion, and the source entity reference may be lost.
3750 and then Is_Entity_Name
(A
)
3751 and then Comes_From_Source
(A
)
3753 -- Annotate the tree by creating a variable reference marker when
3754 -- the actual denotes a variable reference, in case the reference
3755 -- is folded or optimized away. The variable reference marker is
3756 -- automatically saved for later examination by the ABE Processing
3757 -- phase. The status of the reference is set as follows:
3761 -- write IN OUT, OUT
3763 Build_Variable_Reference_Marker
3765 Read
=> Ekind
(F
) /= E_Out_Parameter
,
3766 Write
=> Ekind
(F
) /= E_In_Parameter
);
3768 Orig_A
:= Entity
(A
);
3770 if Present
(Orig_A
) then
3771 if Is_Formal
(Orig_A
)
3772 and then Ekind
(F
) /= E_In_Parameter
3774 Generate_Reference
(Orig_A
, A
, 'm');
3776 elsif not Is_Overloaded
(A
) then
3777 if Ekind
(F
) /= E_Out_Parameter
then
3778 Generate_Reference
(Orig_A
, A
);
3780 -- RM 6.4.1(12): For an out parameter that is passed by
3781 -- copy, the formal parameter object is created, and:
3783 -- * For an access type, the formal parameter is initialized
3784 -- from the value of the actual, without checking that the
3785 -- value satisfies any constraint, any predicate, or any
3786 -- exclusion of the null value.
3788 -- * For a scalar type that has the Default_Value aspect
3789 -- specified, the formal parameter is initialized from the
3790 -- value of the actual, without checking that the value
3791 -- satisfies any constraint or any predicate.
3792 -- I do not understand why this case is included??? this is
3793 -- not a case where an OUT parameter is treated as IN OUT.
3795 -- * For a composite type with discriminants or that has
3796 -- implicit initial values for any subcomponents, the
3797 -- behavior is as for an in out parameter passed by copy.
3799 -- Hence for these cases we generate the read reference now
3800 -- (the write reference will be generated later by
3801 -- Note_Possible_Modification).
3803 elsif Is_By_Copy_Type
(Etype
(F
))
3805 (Is_Access_Type
(Etype
(F
))
3807 (Is_Scalar_Type
(Etype
(F
))
3809 Present
(Default_Aspect_Value
(Etype
(F
))))
3811 (Is_Composite_Type
(Etype
(F
))
3812 and then (Has_Discriminants
(Etype
(F
))
3813 or else Is_Partially_Initialized_Type
3816 Generate_Reference
(Orig_A
, A
);
3823 and then (Nkind
(Parent
(A
)) /= N_Parameter_Association
3824 or else Chars
(Selector_Name
(Parent
(A
))) = Chars
(F
))
3826 -- If style checking mode on, check match of formal name
3829 if Nkind
(Parent
(A
)) = N_Parameter_Association
then
3830 Check_Identifier
(Selector_Name
(Parent
(A
)), F
);
3834 -- If the formal is Out or In_Out, do not resolve and expand the
3835 -- conversion, because it is subsequently expanded into explicit
3836 -- temporaries and assignments. However, the object of the
3837 -- conversion can be resolved. An exception is the case of tagged
3838 -- type conversion with a class-wide actual. In that case we want
3839 -- the tag check to occur and no temporary will be needed (no
3840 -- representation change can occur) and the parameter is passed by
3841 -- reference, so we go ahead and resolve the type conversion.
3842 -- Another exception is the case of reference to component or
3843 -- subcomponent of a bit-packed array, in which case we want to
3844 -- defer expansion to the point the in and out assignments are
3847 if Ekind
(F
) /= E_In_Parameter
3848 and then Nkind
(A
) = N_Type_Conversion
3849 and then not Is_Class_Wide_Type
(Etype
(Expression
(A
)))
3851 if Ekind
(F
) = E_In_Out_Parameter
3852 and then Is_Array_Type
(Etype
(F
))
3854 -- In a view conversion, the conversion must be legal in
3855 -- both directions, and thus both component types must be
3856 -- aliased, or neither (4.6 (8)).
3858 -- The extra rule in 4.6 (24.9.2) seems unduly restrictive:
3859 -- the privacy requirement should not apply to generic
3860 -- types, and should be checked in an instance. ARG query
3863 if Has_Aliased_Components
(Etype
(Expression
(A
))) /=
3864 Has_Aliased_Components
(Etype
(F
))
3867 ("both component types in a view conversion must be"
3868 & " aliased, or neither", A
);
3870 -- Comment here??? what set of cases???
3873 not Same_Ancestor
(Etype
(F
), Etype
(Expression
(A
)))
3875 -- Check view conv between unrelated by ref array types
3877 if Is_By_Reference_Type
(Etype
(F
))
3878 or else Is_By_Reference_Type
(Etype
(Expression
(A
)))
3881 ("view conversion between unrelated by reference "
3882 & "array types not allowed (\'A'I-00246)", A
);
3884 -- In Ada 2005 mode, check view conversion component
3885 -- type cannot be private, tagged, or volatile. Note
3886 -- that we only apply this to source conversions. The
3887 -- generated code can contain conversions which are
3888 -- not subject to this test, and we cannot extract the
3889 -- component type in such cases since it is not present.
3891 elsif Comes_From_Source
(A
)
3892 and then Ada_Version
>= Ada_2005
3895 Comp_Type
: constant Entity_Id
:=
3897 (Etype
(Expression
(A
)));
3899 if (Is_Private_Type
(Comp_Type
)
3900 and then not Is_Generic_Type
(Comp_Type
))
3901 or else Is_Tagged_Type
(Comp_Type
)
3902 or else Is_Volatile
(Comp_Type
)
3905 ("component type of a view conversion cannot"
3906 & " be private, tagged, or volatile"
3915 -- Resolve expression if conversion is all OK
3917 if (Conversion_OK
(A
)
3918 or else Valid_Conversion
(A
, Etype
(A
), Expression
(A
)))
3919 and then not Is_Ref_To_Bit_Packed_Array
(Expression
(A
))
3921 Resolve
(Expression
(A
));
3924 -- If the actual is a function call that returns a limited
3925 -- unconstrained object that needs finalization, create a
3926 -- transient scope for it, so that it can receive the proper
3927 -- finalization list.
3929 elsif Nkind
(A
) = N_Function_Call
3930 and then Is_Limited_Record
(Etype
(F
))
3931 and then not Is_Constrained
(Etype
(F
))
3932 and then Expander_Active
3933 and then (Is_Controlled
(Etype
(F
)) or else Has_Task
(Etype
(F
)))
3935 Establish_Transient_Scope
(A
, Sec_Stack
=> False);
3936 Resolve
(A
, Etype
(F
));
3938 -- A small optimization: if one of the actuals is a concatenation
3939 -- create a block around a procedure call to recover stack space.
3940 -- This alleviates stack usage when several procedure calls in
3941 -- the same statement list use concatenation. We do not perform
3942 -- this wrapping for code statements, where the argument is a
3943 -- static string, and we want to preserve warnings involving
3944 -- sequences of such statements.
3946 elsif Nkind
(A
) = N_Op_Concat
3947 and then Nkind
(N
) = N_Procedure_Call_Statement
3948 and then Expander_Active
3950 not (Is_Intrinsic_Subprogram
(Nam
)
3951 and then Chars
(Nam
) = Name_Asm
)
3952 and then not Static_Concatenation
(A
)
3954 Establish_Transient_Scope
(A
, Sec_Stack
=> False);
3955 Resolve
(A
, Etype
(F
));
3958 if Nkind
(A
) = N_Type_Conversion
3959 and then Is_Array_Type
(Etype
(F
))
3960 and then not Same_Ancestor
(Etype
(F
), Etype
(Expression
(A
)))
3962 (Is_Limited_Type
(Etype
(F
))
3963 or else Is_Limited_Type
(Etype
(Expression
(A
))))
3966 ("conversion between unrelated limited array types "
3967 & "not allowed ('A'I-00246)", A
);
3969 if Is_Limited_Type
(Etype
(F
)) then
3970 Explain_Limited_Type
(Etype
(F
), A
);
3973 if Is_Limited_Type
(Etype
(Expression
(A
))) then
3974 Explain_Limited_Type
(Etype
(Expression
(A
)), A
);
3978 -- (Ada 2005: AI-251): If the actual is an allocator whose
3979 -- directly designated type is a class-wide interface, we build
3980 -- an anonymous access type to use it as the type of the
3981 -- allocator. Later, when the subprogram call is expanded, if
3982 -- the interface has a secondary dispatch table the expander
3983 -- will add a type conversion to force the correct displacement
3986 if Nkind
(A
) = N_Allocator
then
3988 DDT
: constant Entity_Id
:=
3989 Directly_Designated_Type
(Base_Type
(Etype
(F
)));
3991 New_Itype
: Entity_Id
;
3994 if Is_Class_Wide_Type
(DDT
)
3995 and then Is_Interface
(DDT
)
3997 New_Itype
:= Create_Itype
(E_Anonymous_Access_Type
, A
);
3998 Set_Etype
(New_Itype
, Etype
(A
));
3999 Set_Directly_Designated_Type
4000 (New_Itype
, Directly_Designated_Type
(Etype
(A
)));
4001 Set_Etype
(A
, New_Itype
);
4004 -- Ada 2005, AI-162:If the actual is an allocator, the
4005 -- innermost enclosing statement is the master of the
4006 -- created object. This needs to be done with expansion
4007 -- enabled only, otherwise the transient scope will not
4008 -- be removed in the expansion of the wrapped construct.
4010 if (Is_Controlled
(DDT
) or else Has_Task
(DDT
))
4011 and then Expander_Active
4013 Establish_Transient_Scope
(A
, Sec_Stack
=> False);
4017 if Ekind
(Etype
(F
)) = E_Anonymous_Access_Type
then
4018 Check_Restriction
(No_Access_Parameter_Allocators
, A
);
4022 -- (Ada 2005): The call may be to a primitive operation of a
4023 -- tagged synchronized type, declared outside of the type. In
4024 -- this case the controlling actual must be converted to its
4025 -- corresponding record type, which is the formal type. The
4026 -- actual may be a subtype, either because of a constraint or
4027 -- because it is a generic actual, so use base type to locate
4030 F_Typ
:= Base_Type
(Etype
(F
));
4032 if Is_Tagged_Type
(F_Typ
)
4033 and then (Is_Concurrent_Type
(F_Typ
)
4034 or else Is_Concurrent_Record_Type
(F_Typ
))
4036 -- If the actual is overloaded, look for an interpretation
4037 -- that has a synchronized type.
4039 if not Is_Overloaded
(A
) then
4040 A_Typ
:= Base_Type
(Etype
(A
));
4044 Index
: Interp_Index
;
4048 Get_First_Interp
(A
, Index
, It
);
4049 while Present
(It
.Typ
) loop
4050 if Is_Concurrent_Type
(It
.Typ
)
4051 or else Is_Concurrent_Record_Type
(It
.Typ
)
4053 A_Typ
:= Base_Type
(It
.Typ
);
4057 Get_Next_Interp
(Index
, It
);
4063 Full_A_Typ
: Entity_Id
;
4066 if Present
(Full_View
(A_Typ
)) then
4067 Full_A_Typ
:= Base_Type
(Full_View
(A_Typ
));
4069 Full_A_Typ
:= A_Typ
;
4072 -- Tagged synchronized type (case 1): the actual is a
4075 if Is_Concurrent_Type
(A_Typ
)
4076 and then Corresponding_Record_Type
(A_Typ
) = F_Typ
4079 Unchecked_Convert_To
4080 (Corresponding_Record_Type
(A_Typ
), A
));
4081 Resolve
(A
, Etype
(F
));
4083 -- Tagged synchronized type (case 2): the formal is a
4086 elsif Ekind
(Full_A_Typ
) = E_Record_Type
4088 (Corresponding_Concurrent_Type
(Full_A_Typ
))
4089 and then Is_Concurrent_Type
(F_Typ
)
4090 and then Present
(Corresponding_Record_Type
(F_Typ
))
4091 and then Full_A_Typ
= Corresponding_Record_Type
(F_Typ
)
4093 Resolve
(A
, Corresponding_Record_Type
(F_Typ
));
4098 Resolve
(A
, Etype
(F
));
4102 -- Not a synchronized operation
4105 Resolve
(A
, Etype
(F
));
4112 -- An actual cannot be an untagged formal incomplete type
4114 if Ekind
(A_Typ
) = E_Incomplete_Type
4115 and then not Is_Tagged_Type
(A_Typ
)
4116 and then Is_Generic_Type
(A_Typ
)
4119 ("invalid use of untagged formal incomplete type", A
);
4122 if Comes_From_Source
(Original_Node
(N
))
4123 and then Nkind_In
(Original_Node
(N
), N_Function_Call
,
4124 N_Procedure_Call_Statement
)
4126 -- In formal mode, check that actual parameters matching
4127 -- formals of tagged types are objects (or ancestor type
4128 -- conversions of objects), not general expressions.
4130 if Is_Actual_Tagged_Parameter
(A
) then
4131 if Is_SPARK_05_Object_Reference
(A
) then
4134 elsif Nkind
(A
) = N_Type_Conversion
then
4136 Operand
: constant Node_Id
:= Expression
(A
);
4137 Operand_Typ
: constant Entity_Id
:= Etype
(Operand
);
4138 Target_Typ
: constant Entity_Id
:= A_Typ
;
4141 if not Is_SPARK_05_Object_Reference
(Operand
) then
4142 Check_SPARK_05_Restriction
4143 ("object required", Operand
);
4145 -- In formal mode, the only view conversions are those
4146 -- involving ancestor conversion of an extended type.
4149 (Is_Tagged_Type
(Target_Typ
)
4150 and then not Is_Class_Wide_Type
(Target_Typ
)
4151 and then Is_Tagged_Type
(Operand_Typ
)
4152 and then not Is_Class_Wide_Type
(Operand_Typ
)
4153 and then Is_Ancestor
(Target_Typ
, Operand_Typ
))
4156 (F
, E_Out_Parameter
, E_In_Out_Parameter
)
4158 Check_SPARK_05_Restriction
4159 ("ancestor conversion is the only permitted "
4160 & "view conversion", A
);
4162 Check_SPARK_05_Restriction
4163 ("ancestor conversion required", A
);
4172 Check_SPARK_05_Restriction
("object required", A
);
4175 -- In formal mode, the only view conversions are those
4176 -- involving ancestor conversion of an extended type.
4178 elsif Nkind
(A
) = N_Type_Conversion
4179 and then Ekind_In
(F
, E_Out_Parameter
, E_In_Out_Parameter
)
4181 Check_SPARK_05_Restriction
4182 ("ancestor conversion is the only permitted view "
4187 -- has warnings suppressed, then we reset Never_Set_In_Source for
4188 -- the calling entity. The reason for this is to catch cases like
4189 -- GNAT.Spitbol.Patterns.Vstring_Var where the called subprogram
4190 -- uses trickery to modify an IN parameter.
4192 if Ekind
(F
) = E_In_Parameter
4193 and then Is_Entity_Name
(A
)
4194 and then Present
(Entity
(A
))
4195 and then Ekind
(Entity
(A
)) = E_Variable
4196 and then Has_Warnings_Off
(F_Typ
)
4198 Set_Never_Set_In_Source
(Entity
(A
), False);
4201 -- Perform error checks for IN and IN OUT parameters
4203 if Ekind
(F
) /= E_Out_Parameter
then
4205 -- Check unset reference. For scalar parameters, it is clearly
4206 -- wrong to pass an uninitialized value as either an IN or
4207 -- IN-OUT parameter. For composites, it is also clearly an
4208 -- error to pass a completely uninitialized value as an IN
4209 -- parameter, but the case of IN OUT is trickier. We prefer
4210 -- not to give a warning here. For example, suppose there is
4211 -- a routine that sets some component of a record to False.
4212 -- It is perfectly reasonable to make this IN-OUT and allow
4213 -- either initialized or uninitialized records to be passed
4216 -- For partially initialized composite values, we also avoid
4217 -- warnings, since it is quite likely that we are passing a
4218 -- partially initialized value and only the initialized fields
4219 -- will in fact be read in the subprogram.
4221 if Is_Scalar_Type
(A_Typ
)
4222 or else (Ekind
(F
) = E_In_Parameter
4223 and then not Is_Partially_Initialized_Type
(A_Typ
))
4225 Check_Unset_Reference
(A
);
4228 -- In Ada 83 we cannot pass an OUT parameter as an IN or IN OUT
4229 -- actual to a nested call, since this constitutes a reading of
4230 -- the parameter, which is not allowed.
4232 if Ada_Version
= Ada_83
4233 and then Is_Entity_Name
(A
)
4234 and then Ekind
(Entity
(A
)) = E_Out_Parameter
4236 Error_Msg_N
("(Ada 83) illegal reading of out parameter", A
);
4240 -- In -gnatd.q mode, forget that a given array is constant when
4241 -- it is passed as an IN parameter to a foreign-convention
4242 -- subprogram. This is in case the subprogram evilly modifies the
4243 -- object. Of course, correct code would use IN OUT.
4246 and then Ekind
(F
) = E_In_Parameter
4247 and then Has_Foreign_Convention
(Nam
)
4248 and then Is_Array_Type
(F_Typ
)
4249 and then Nkind
(A
) in N_Has_Entity
4250 and then Present
(Entity
(A
))
4252 Set_Is_True_Constant
(Entity
(A
), False);
4255 -- Case of OUT or IN OUT parameter
4257 if Ekind
(F
) /= E_In_Parameter
then
4259 -- For an Out parameter, check for useless assignment. Note
4260 -- that we can't set Last_Assignment this early, because we may
4261 -- kill current values in Resolve_Call, and that call would
4262 -- clobber the Last_Assignment field.
4264 -- Note: call Warn_On_Useless_Assignment before doing the check
4265 -- below for Is_OK_Variable_For_Out_Formal so that the setting
4266 -- of Referenced_As_LHS/Referenced_As_Out_Formal properly
4267 -- reflects the last assignment, not this one.
4269 if Ekind
(F
) = E_Out_Parameter
then
4270 if Warn_On_Modified_As_Out_Parameter
(F
)
4271 and then Is_Entity_Name
(A
)
4272 and then Present
(Entity
(A
))
4273 and then Comes_From_Source
(N
)
4275 Warn_On_Useless_Assignment
(Entity
(A
), A
);
4279 -- Validate the form of the actual. Note that the call to
4280 -- Is_OK_Variable_For_Out_Formal generates the required
4281 -- reference in this case.
4283 -- A call to an initialization procedure for an aggregate
4284 -- component may initialize a nested component of a constant
4285 -- designated object. In this context the object is variable.
4287 if not Is_OK_Variable_For_Out_Formal
(A
)
4288 and then not Is_Init_Proc
(Nam
)
4290 Error_Msg_NE
("actual for& must be a variable", A
, F
);
4292 if Is_Subprogram
(Current_Scope
) then
4293 if Is_Invariant_Procedure
(Current_Scope
)
4294 or else Is_Partial_Invariant_Procedure
(Current_Scope
)
4297 ("function used in invariant cannot modify its "
4300 elsif Is_Predicate_Function
(Current_Scope
) then
4302 ("function used in predicate cannot modify its "
4308 -- What's the following about???
4310 if Is_Entity_Name
(A
) then
4311 Kill_Checks
(Entity
(A
));
4317 if Etype
(A
) = Any_Type
then
4318 Set_Etype
(N
, Any_Type
);
4322 -- Apply appropriate constraint/predicate checks for IN [OUT] case
4324 if Ekind_In
(F
, E_In_Parameter
, E_In_Out_Parameter
) then
4326 -- Apply predicate tests except in certain special cases. Note
4327 -- that it might be more consistent to apply these only when
4328 -- expansion is active (in Exp_Ch6.Expand_Actuals), as we do
4329 -- for the outbound predicate tests ??? In any case indicate
4330 -- the function being called, for better warnings if the call
4331 -- leads to an infinite recursion.
4333 if Predicate_Tests_On_Arguments
(Nam
) then
4334 Apply_Predicate_Check
(A
, F_Typ
, Nam
);
4337 -- Apply required constraint checks
4339 -- Gigi looks at the check flag and uses the appropriate types.
4340 -- For now since one flag is used there is an optimization
4341 -- which might not be done in the IN OUT case since Gigi does
4342 -- not do any analysis. More thought required about this ???
4344 -- In fact is this comment obsolete??? doesn't the expander now
4345 -- generate all these tests anyway???
4347 if Is_Scalar_Type
(Etype
(A
)) then
4348 Apply_Scalar_Range_Check
(A
, F_Typ
);
4350 elsif Is_Array_Type
(Etype
(A
)) then
4351 Apply_Length_Check
(A
, F_Typ
);
4353 elsif Is_Record_Type
(F_Typ
)
4354 and then Has_Discriminants
(F_Typ
)
4355 and then Is_Constrained
(F_Typ
)
4356 and then (not Is_Derived_Type
(F_Typ
)
4357 or else Comes_From_Source
(Nam
))
4359 Apply_Discriminant_Check
(A
, F_Typ
);
4361 -- For view conversions of a discriminated object, apply
4362 -- check to object itself, the conversion alreay has the
4365 if Nkind
(A
) = N_Type_Conversion
4366 and then Is_Constrained
(Etype
(Expression
(A
)))
4368 Apply_Discriminant_Check
(Expression
(A
), F_Typ
);
4371 elsif Is_Access_Type
(F_Typ
)
4372 and then Is_Array_Type
(Designated_Type
(F_Typ
))
4373 and then Is_Constrained
(Designated_Type
(F_Typ
))
4375 Apply_Length_Check
(A
, F_Typ
);
4377 elsif Is_Access_Type
(F_Typ
)
4378 and then Has_Discriminants
(Designated_Type
(F_Typ
))
4379 and then Is_Constrained
(Designated_Type
(F_Typ
))
4381 Apply_Discriminant_Check
(A
, F_Typ
);
4384 Apply_Range_Check
(A
, F_Typ
);
4387 -- Ada 2005 (AI-231): Note that the controlling parameter case
4388 -- already existed in Ada 95, which is partially checked
4389 -- elsewhere (see Checks), and we don't want the warning
4390 -- message to differ.
4392 if Is_Access_Type
(F_Typ
)
4393 and then Can_Never_Be_Null
(F_Typ
)
4394 and then Known_Null
(A
)
4396 if Is_Controlling_Formal
(F
) then
4397 Apply_Compile_Time_Constraint_Error
4399 Msg
=> "null value not allowed here??",
4400 Reason
=> CE_Access_Check_Failed
);
4402 elsif Ada_Version
>= Ada_2005
then
4403 Apply_Compile_Time_Constraint_Error
4405 Msg
=> "(Ada 2005) null not allowed in "
4406 & "null-excluding formal??",
4407 Reason
=> CE_Null_Not_Allowed
);
4412 -- Checks for OUT parameters and IN OUT parameters
4414 if Ekind_In
(F
, E_Out_Parameter
, E_In_Out_Parameter
) then
4416 -- If there is a type conversion, make sure the return value
4417 -- meets the constraints of the variable before the conversion.
4419 if Nkind
(A
) = N_Type_Conversion
then
4420 if Is_Scalar_Type
(A_Typ
) then
4421 Apply_Scalar_Range_Check
4422 (Expression
(A
), Etype
(Expression
(A
)), A_Typ
);
4424 -- In addition, the returned value of the parameter must
4425 -- satisfy the bounds of the object type (see comment
4428 Apply_Scalar_Range_Check
(A
, A_Typ
, F_Typ
);
4432 (Expression
(A
), Etype
(Expression
(A
)), A_Typ
);
4435 -- If no conversion, apply scalar range checks and length check
4436 -- based on the subtype of the actual (NOT that of the formal).
4437 -- This indicates that the check takes place on return from the
4438 -- call. During expansion the required constraint checks are
4439 -- inserted. In GNATprove mode, in the absence of expansion,
4440 -- the flag indicates that the returned value is valid.
4443 if Is_Scalar_Type
(F_Typ
) then
4444 Apply_Scalar_Range_Check
(A
, A_Typ
, F_Typ
);
4446 elsif Is_Array_Type
(F_Typ
)
4447 and then Ekind
(F
) = E_Out_Parameter
4449 Apply_Length_Check
(A
, F_Typ
);
4451 Apply_Range_Check
(A
, A_Typ
, F_Typ
);
4455 -- Note: we do not apply the predicate checks for the case of
4456 -- OUT and IN OUT parameters. They are instead applied in the
4457 -- Expand_Actuals routine in Exp_Ch6.
4460 -- An actual associated with an access parameter is implicitly
4461 -- converted to the anonymous access type of the formal and must
4462 -- satisfy the legality checks for access conversions.
4464 if Ekind
(F_Typ
) = E_Anonymous_Access_Type
then
4465 if not Valid_Conversion
(A
, F_Typ
, A
) then
4467 ("invalid implicit conversion for access parameter", A
);
4470 -- If the actual is an access selected component of a variable,
4471 -- the call may modify its designated object. It is reasonable
4472 -- to treat this as a potential modification of the enclosing
4473 -- record, to prevent spurious warnings that it should be
4474 -- declared as a constant, because intuitively programmers
4475 -- regard the designated subcomponent as part of the record.
4477 if Nkind
(A
) = N_Selected_Component
4478 and then Is_Entity_Name
(Prefix
(A
))
4479 and then not Is_Constant_Object
(Entity
(Prefix
(A
)))
4481 Note_Possible_Modification
(A
, Sure
=> False);
4485 -- Check bad case of atomic/volatile argument (RM C.6(12))
4487 if Is_By_Reference_Type
(Etype
(F
))
4488 and then Comes_From_Source
(N
)
4490 if Is_Atomic_Object
(A
)
4491 and then not Is_Atomic
(Etype
(F
))
4494 ("cannot pass atomic argument to non-atomic formal&",
4497 elsif Is_Volatile_Object
(A
)
4498 and then not Is_Volatile
(Etype
(F
))
4501 ("cannot pass volatile argument to non-volatile formal&",
4506 -- Check that subprograms don't have improper controlling
4507 -- arguments (RM 3.9.2 (9)).
4509 -- A primitive operation may have an access parameter of an
4510 -- incomplete tagged type, but a dispatching call is illegal
4511 -- if the type is still incomplete.
4513 if Is_Controlling_Formal
(F
) then
4514 Set_Is_Controlling_Actual
(A
);
4516 if Ekind
(Etype
(F
)) = E_Anonymous_Access_Type
then
4518 Desig
: constant Entity_Id
:= Designated_Type
(Etype
(F
));
4520 if Ekind
(Desig
) = E_Incomplete_Type
4521 and then No
(Full_View
(Desig
))
4522 and then No
(Non_Limited_View
(Desig
))
4525 ("premature use of incomplete type& "
4526 & "in dispatching call", A
, Desig
);
4531 elsif Nkind
(A
) = N_Explicit_Dereference
then
4532 Validate_Remote_Access_To_Class_Wide_Type
(A
);
4535 -- Apply legality rule 3.9.2 (9/1)
4537 if (Is_Class_Wide_Type
(A_Typ
) or else Is_Dynamically_Tagged
(A
))
4538 and then not Is_Class_Wide_Type
(F_Typ
)
4539 and then not Is_Controlling_Formal
(F
)
4540 and then not In_Instance
4542 Error_Msg_N
("class-wide argument not allowed here!", A
);
4544 if Is_Subprogram
(Nam
) and then Comes_From_Source
(Nam
) then
4545 Error_Msg_Node_2
:= F_Typ
;
4547 ("& is not a dispatching operation of &!", A
, Nam
);
4550 -- Apply the checks described in 3.10.2(27): if the context is a
4551 -- specific access-to-object, the actual cannot be class-wide.
4552 -- Use base type to exclude access_to_subprogram cases.
4554 elsif Is_Access_Type
(A_Typ
)
4555 and then Is_Access_Type
(F_Typ
)
4556 and then not Is_Access_Subprogram_Type
(Base_Type
(F_Typ
))
4557 and then (Is_Class_Wide_Type
(Designated_Type
(A_Typ
))
4558 or else (Nkind
(A
) = N_Attribute_Reference
4560 Is_Class_Wide_Type
(Etype
(Prefix
(A
)))))
4561 and then not Is_Class_Wide_Type
(Designated_Type
(F_Typ
))
4562 and then not Is_Controlling_Formal
(F
)
4564 -- Disable these checks for call to imported C++ subprograms
4567 (Is_Entity_Name
(Name
(N
))
4568 and then Is_Imported
(Entity
(Name
(N
)))
4569 and then Convention
(Entity
(Name
(N
))) = Convention_CPP
)
4572 ("access to class-wide argument not allowed here!", A
);
4574 if Is_Subprogram
(Nam
) and then Comes_From_Source
(Nam
) then
4575 Error_Msg_Node_2
:= Designated_Type
(F_Typ
);
4577 ("& is not a dispatching operation of &!", A
, Nam
);
4581 Check_Aliased_Parameter
;
4585 -- If it is a named association, treat the selector_name as a
4586 -- proper identifier, and mark the corresponding entity.
4588 if Nkind
(Parent
(A
)) = N_Parameter_Association
4590 -- Ignore reference in SPARK mode, as it refers to an entity not
4591 -- in scope at the point of reference, so the reference should
4592 -- be ignored for computing effects of subprograms.
4594 and then not GNATprove_Mode
4596 -- If subprogram is overridden, use name of formal that
4599 if Present
(Real_Subp
) then
4600 Set_Entity
(Selector_Name
(Parent
(A
)), Real_F
);
4601 Set_Etype
(Selector_Name
(Parent
(A
)), Etype
(Real_F
));
4604 Set_Entity
(Selector_Name
(Parent
(A
)), F
);
4605 Generate_Reference
(F
, Selector_Name
(Parent
(A
)));
4606 Set_Etype
(Selector_Name
(Parent
(A
)), F_Typ
);
4607 Generate_Reference
(F_Typ
, N
, ' ');
4613 if Ekind
(F
) /= E_Out_Parameter
then
4614 Check_Unset_Reference
(A
);
4617 -- The following checks are only relevant when SPARK_Mode is on as
4618 -- they are not standard Ada legality rule. Internally generated
4619 -- temporaries are ignored.
4621 if SPARK_Mode
= On
and then Comes_From_Source
(A
) then
4623 -- An effectively volatile object may act as an actual when the
4624 -- corresponding formal is of a non-scalar effectively volatile
4625 -- type (SPARK RM 7.1.3(11)).
4627 if not Is_Scalar_Type
(Etype
(F
))
4628 and then Is_Effectively_Volatile
(Etype
(F
))
4632 -- An effectively volatile object may act as an actual in a
4633 -- call to an instance of Unchecked_Conversion.
4634 -- (SPARK RM 7.1.3(11)).
4636 elsif Is_Unchecked_Conversion_Instance
(Nam
) then
4639 -- The actual denotes an object
4641 elsif Is_Effectively_Volatile_Object
(A
) then
4643 ("volatile object cannot act as actual in a call (SPARK "
4644 & "RM 7.1.3(11))", A
);
4646 -- Otherwise the actual denotes an expression. Inspect the
4647 -- expression and flag each effectively volatile object with
4648 -- enabled property Async_Writers or Effective_Reads as illegal
4649 -- because it apprears within an interfering context. Note that
4650 -- this is usually done in Resolve_Entity_Name, but when the
4651 -- effectively volatile object appears as an actual in a call,
4652 -- the call must be resolved first.
4655 Flag_Effectively_Volatile_Objects
(A
);
4658 -- An effectively volatile variable cannot act as an actual
4659 -- parameter in a procedure call when the variable has enabled
4660 -- property Effective_Reads and the corresponding formal is of
4661 -- mode IN (SPARK RM 7.1.3(10)).
4663 if Ekind
(Nam
) = E_Procedure
4664 and then Ekind
(F
) = E_In_Parameter
4665 and then Is_Entity_Name
(A
)
4669 if Ekind
(A_Id
) = E_Variable
4670 and then Is_Effectively_Volatile
(Etype
(A_Id
))
4671 and then Effective_Reads_Enabled
(A_Id
)
4674 ("effectively volatile variable & cannot appear as "
4675 & "actual in procedure call", A
, A_Id
);
4677 Error_Msg_Name_1
:= Name_Effective_Reads
;
4678 Error_Msg_N
("\\variable has enabled property %", A
);
4679 Error_Msg_N
("\\corresponding formal has mode IN", A
);
4684 -- A formal parameter of a specific tagged type whose related
4685 -- subprogram is subject to pragma Extensions_Visible with value
4686 -- "False" cannot act as an actual in a subprogram with value
4687 -- "True" (SPARK RM 6.1.7(3)).
4689 if Is_EVF_Expression
(A
)
4690 and then Extensions_Visible_Status
(Nam
) =
4691 Extensions_Visible_True
4694 ("formal parameter cannot act as actual parameter when "
4695 & "Extensions_Visible is False", A
);
4697 ("\subprogram & has Extensions_Visible True", A
, Nam
);
4700 -- The actual parameter of a Ghost subprogram whose formal is of
4701 -- mode IN OUT or OUT must be a Ghost variable (SPARK RM 6.9(12)).
4703 if Comes_From_Source
(Nam
)
4704 and then Is_Ghost_Entity
(Nam
)
4705 and then Ekind_In
(F
, E_In_Out_Parameter
, E_Out_Parameter
)
4706 and then Is_Entity_Name
(A
)
4707 and then Present
(Entity
(A
))
4708 and then not Is_Ghost_Entity
(Entity
(A
))
4711 ("non-ghost variable & cannot appear as actual in call to "
4712 & "ghost procedure", A
, Entity
(A
));
4714 if Ekind
(F
) = E_In_Out_Parameter
then
4715 Error_Msg_N
("\corresponding formal has mode `IN OUT`", A
);
4717 Error_Msg_N
("\corresponding formal has mode OUT", A
);
4723 -- Case where actual is not present
4731 if Present
(Real_Subp
) then
4732 Next_Formal
(Real_F
);
4735 end Resolve_Actuals
;
4737 -----------------------
4738 -- Resolve_Allocator --
4739 -----------------------
4741 procedure Resolve_Allocator
(N
: Node_Id
; Typ
: Entity_Id
) is
4742 Desig_T
: constant Entity_Id
:= Designated_Type
(Typ
);
4743 E
: constant Node_Id
:= Expression
(N
);
4745 Discrim
: Entity_Id
;
4748 Assoc
: Node_Id
:= Empty
;
4751 procedure Check_Allocator_Discrim_Accessibility
4752 (Disc_Exp
: Node_Id
;
4753 Alloc_Typ
: Entity_Id
);
4754 -- Check that accessibility level associated with an access discriminant
4755 -- initialized in an allocator by the expression Disc_Exp is not deeper
4756 -- than the level of the allocator type Alloc_Typ. An error message is
4757 -- issued if this condition is violated. Specialized checks are done for
4758 -- the cases of a constraint expression which is an access attribute or
4759 -- an access discriminant.
4761 function In_Dispatching_Context
return Boolean;
4762 -- If the allocator is an actual in a call, it is allowed to be class-
4763 -- wide when the context is not because it is a controlling actual.
4765 -------------------------------------------
4766 -- Check_Allocator_Discrim_Accessibility --
4767 -------------------------------------------
4769 procedure Check_Allocator_Discrim_Accessibility
4770 (Disc_Exp
: Node_Id
;
4771 Alloc_Typ
: Entity_Id
)
4774 if Type_Access_Level
(Etype
(Disc_Exp
)) >
4775 Deepest_Type_Access_Level
(Alloc_Typ
)
4778 ("operand type has deeper level than allocator type", Disc_Exp
);
4780 -- When the expression is an Access attribute the level of the prefix
4781 -- object must not be deeper than that of the allocator's type.
4783 elsif Nkind
(Disc_Exp
) = N_Attribute_Reference
4784 and then Get_Attribute_Id
(Attribute_Name
(Disc_Exp
)) =
4786 and then Object_Access_Level
(Prefix
(Disc_Exp
)) >
4787 Deepest_Type_Access_Level
(Alloc_Typ
)
4790 ("prefix of attribute has deeper level than allocator type",
4793 -- When the expression is an access discriminant the check is against
4794 -- the level of the prefix object.
4796 elsif Ekind
(Etype
(Disc_Exp
)) = E_Anonymous_Access_Type
4797 and then Nkind
(Disc_Exp
) = N_Selected_Component
4798 and then Object_Access_Level
(Prefix
(Disc_Exp
)) >
4799 Deepest_Type_Access_Level
(Alloc_Typ
)
4802 ("access discriminant has deeper level than allocator type",
4805 -- All other cases are legal
4810 end Check_Allocator_Discrim_Accessibility
;
4812 ----------------------------
4813 -- In_Dispatching_Context --
4814 ----------------------------
4816 function In_Dispatching_Context
return Boolean is
4817 Par
: constant Node_Id
:= Parent
(N
);
4820 return Nkind
(Par
) in N_Subprogram_Call
4821 and then Is_Entity_Name
(Name
(Par
))
4822 and then Is_Dispatching_Operation
(Entity
(Name
(Par
)));
4823 end In_Dispatching_Context
;
4825 -- Start of processing for Resolve_Allocator
4828 -- Replace general access with specific type
4830 if Ekind
(Etype
(N
)) = E_Allocator_Type
then
4831 Set_Etype
(N
, Base_Type
(Typ
));
4834 if Is_Abstract_Type
(Typ
) then
4835 Error_Msg_N
("type of allocator cannot be abstract", N
);
4838 -- For qualified expression, resolve the expression using the given
4839 -- subtype (nothing to do for type mark, subtype indication)
4841 if Nkind
(E
) = N_Qualified_Expression
then
4842 if Is_Class_Wide_Type
(Etype
(E
))
4843 and then not Is_Class_Wide_Type
(Desig_T
)
4844 and then not In_Dispatching_Context
4847 ("class-wide allocator not allowed for this access type", N
);
4850 Resolve
(Expression
(E
), Etype
(E
));
4851 Check_Non_Static_Context
(Expression
(E
));
4852 Check_Unset_Reference
(Expression
(E
));
4854 -- Allocators generated by the build-in-place expansion mechanism
4855 -- are explicitly marked as coming from source but do not need to be
4856 -- checked for limited initialization. To exclude this case, ensure
4857 -- that the parent of the allocator is a source node.
4858 -- The return statement constructed for an Expression_Function does
4859 -- not come from source but requires a limited check.
4861 if Is_Limited_Type
(Etype
(E
))
4862 and then Comes_From_Source
(N
)
4864 (Comes_From_Source
(Parent
(N
))
4866 (Ekind
(Current_Scope
) = E_Function
4867 and then Nkind
(Original_Node
(Unit_Declaration_Node
4868 (Current_Scope
))) = N_Expression_Function
))
4869 and then not In_Instance_Body
4871 if not OK_For_Limited_Init
(Etype
(E
), Expression
(E
)) then
4872 if Nkind
(Parent
(N
)) = N_Assignment_Statement
then
4874 ("illegal expression for initialized allocator of a "
4875 & "limited type (RM 7.5 (2.7/2))", N
);
4878 ("initialization not allowed for limited types", N
);
4881 Explain_Limited_Type
(Etype
(E
), N
);
4885 -- A qualified expression requires an exact match of the type. Class-
4886 -- wide matching is not allowed.
4888 if (Is_Class_Wide_Type
(Etype
(Expression
(E
)))
4889 or else Is_Class_Wide_Type
(Etype
(E
)))
4890 and then Base_Type
(Etype
(Expression
(E
))) /= Base_Type
(Etype
(E
))
4892 Wrong_Type
(Expression
(E
), Etype
(E
));
4895 -- Calls to build-in-place functions are not currently supported in
4896 -- allocators for access types associated with a simple storage pool.
4897 -- Supporting such allocators may require passing additional implicit
4898 -- parameters to build-in-place functions (or a significant revision
4899 -- of the current b-i-p implementation to unify the handling for
4900 -- multiple kinds of storage pools). ???
4902 if Is_Limited_View
(Desig_T
)
4903 and then Nkind
(Expression
(E
)) = N_Function_Call
4906 Pool
: constant Entity_Id
:=
4907 Associated_Storage_Pool
(Root_Type
(Typ
));
4911 Present
(Get_Rep_Pragma
4912 (Etype
(Pool
), Name_Simple_Storage_Pool_Type
))
4915 ("limited function calls not yet supported in simple "
4916 & "storage pool allocators", Expression
(E
));
4921 -- A special accessibility check is needed for allocators that
4922 -- constrain access discriminants. The level of the type of the
4923 -- expression used to constrain an access discriminant cannot be
4924 -- deeper than the type of the allocator (in contrast to access
4925 -- parameters, where the level of the actual can be arbitrary).
4927 -- We can't use Valid_Conversion to perform this check because in
4928 -- general the type of the allocator is unrelated to the type of
4929 -- the access discriminant.
4931 if Ekind
(Typ
) /= E_Anonymous_Access_Type
4932 or else Is_Local_Anonymous_Access
(Typ
)
4934 Subtyp
:= Entity
(Subtype_Mark
(E
));
4936 Aggr
:= Original_Node
(Expression
(E
));
4938 if Has_Discriminants
(Subtyp
)
4939 and then Nkind_In
(Aggr
, N_Aggregate
, N_Extension_Aggregate
)
4941 Discrim
:= First_Discriminant
(Base_Type
(Subtyp
));
4943 -- Get the first component expression of the aggregate
4945 if Present
(Expressions
(Aggr
)) then
4946 Disc_Exp
:= First
(Expressions
(Aggr
));
4948 elsif Present
(Component_Associations
(Aggr
)) then
4949 Assoc
:= First
(Component_Associations
(Aggr
));
4951 if Present
(Assoc
) then
4952 Disc_Exp
:= Expression
(Assoc
);
4961 while Present
(Discrim
) and then Present
(Disc_Exp
) loop
4962 if Ekind
(Etype
(Discrim
)) = E_Anonymous_Access_Type
then
4963 Check_Allocator_Discrim_Accessibility
(Disc_Exp
, Typ
);
4966 Next_Discriminant
(Discrim
);
4968 if Present
(Discrim
) then
4969 if Present
(Assoc
) then
4971 Disc_Exp
:= Expression
(Assoc
);
4973 elsif Present
(Next
(Disc_Exp
)) then
4977 Assoc
:= First
(Component_Associations
(Aggr
));
4979 if Present
(Assoc
) then
4980 Disc_Exp
:= Expression
(Assoc
);
4990 -- For a subtype mark or subtype indication, freeze the subtype
4993 Freeze_Expression
(E
);
4995 if Is_Access_Constant
(Typ
) and then not No_Initialization
(N
) then
4997 ("initialization required for access-to-constant allocator", N
);
5000 -- A special accessibility check is needed for allocators that
5001 -- constrain access discriminants. The level of the type of the
5002 -- expression used to constrain an access discriminant cannot be
5003 -- deeper than the type of the allocator (in contrast to access
5004 -- parameters, where the level of the actual can be arbitrary).
5005 -- We can't use Valid_Conversion to perform this check because
5006 -- in general the type of the allocator is unrelated to the type
5007 -- of the access discriminant.
5009 if Nkind
(Original_Node
(E
)) = N_Subtype_Indication
5010 and then (Ekind
(Typ
) /= E_Anonymous_Access_Type
5011 or else Is_Local_Anonymous_Access
(Typ
))
5013 Subtyp
:= Entity
(Subtype_Mark
(Original_Node
(E
)));
5015 if Has_Discriminants
(Subtyp
) then
5016 Discrim
:= First_Discriminant
(Base_Type
(Subtyp
));
5017 Constr
:= First
(Constraints
(Constraint
(Original_Node
(E
))));
5018 while Present
(Discrim
) and then Present
(Constr
) loop
5019 if Ekind
(Etype
(Discrim
)) = E_Anonymous_Access_Type
then
5020 if Nkind
(Constr
) = N_Discriminant_Association
then
5021 Disc_Exp
:= Original_Node
(Expression
(Constr
));
5023 Disc_Exp
:= Original_Node
(Constr
);
5026 Check_Allocator_Discrim_Accessibility
(Disc_Exp
, Typ
);
5029 Next_Discriminant
(Discrim
);
5036 -- Ada 2005 (AI-344): A class-wide allocator requires an accessibility
5037 -- check that the level of the type of the created object is not deeper
5038 -- than the level of the allocator's access type, since extensions can
5039 -- now occur at deeper levels than their ancestor types. This is a
5040 -- static accessibility level check; a run-time check is also needed in
5041 -- the case of an initialized allocator with a class-wide argument (see
5042 -- Expand_Allocator_Expression).
5044 if Ada_Version
>= Ada_2005
5045 and then Is_Class_Wide_Type
(Desig_T
)
5048 Exp_Typ
: Entity_Id
;
5051 if Nkind
(E
) = N_Qualified_Expression
then
5052 Exp_Typ
:= Etype
(E
);
5053 elsif Nkind
(E
) = N_Subtype_Indication
then
5054 Exp_Typ
:= Entity
(Subtype_Mark
(Original_Node
(E
)));
5056 Exp_Typ
:= Entity
(E
);
5059 if Type_Access_Level
(Exp_Typ
) >
5060 Deepest_Type_Access_Level
(Typ
)
5062 if In_Instance_Body
then
5063 Error_Msg_Warn
:= SPARK_Mode
/= On
;
5065 ("type in allocator has deeper level than "
5066 & "designated class-wide type<<", E
);
5067 Error_Msg_N
("\Program_Error [<<", E
);
5069 Make_Raise_Program_Error
(Sloc
(N
),
5070 Reason
=> PE_Accessibility_Check_Failed
));
5073 -- Do not apply Ada 2005 accessibility checks on a class-wide
5074 -- allocator if the type given in the allocator is a formal
5075 -- type. A run-time check will be performed in the instance.
5077 elsif not Is_Generic_Type
(Exp_Typ
) then
5078 Error_Msg_N
("type in allocator has deeper level than "
5079 & "designated class-wide type", E
);
5085 -- Check for allocation from an empty storage pool
5087 if No_Pool_Assigned
(Typ
) then
5088 Error_Msg_N
("allocation from empty storage pool!", N
);
5090 -- If the context is an unchecked conversion, as may happen within an
5091 -- inlined subprogram, the allocator is being resolved with its own
5092 -- anonymous type. In that case, if the target type has a specific
5093 -- storage pool, it must be inherited explicitly by the allocator type.
5095 elsif Nkind
(Parent
(N
)) = N_Unchecked_Type_Conversion
5096 and then No
(Associated_Storage_Pool
(Typ
))
5098 Set_Associated_Storage_Pool
5099 (Typ
, Associated_Storage_Pool
(Etype
(Parent
(N
))));
5102 if Ekind
(Etype
(N
)) = E_Anonymous_Access_Type
then
5103 Check_Restriction
(No_Anonymous_Allocators
, N
);
5106 -- Check that an allocator with task parts isn't for a nested access
5107 -- type when restriction No_Task_Hierarchy applies.
5109 if not Is_Library_Level_Entity
(Base_Type
(Typ
))
5110 and then Has_Task
(Base_Type
(Desig_T
))
5112 Check_Restriction
(No_Task_Hierarchy
, N
);
5115 -- An illegal allocator may be rewritten as a raise Program_Error
5118 if Nkind
(N
) = N_Allocator
then
5120 -- Avoid coextension processing for an allocator that is the
5121 -- expansion of a build-in-place function call.
5123 if Nkind
(Original_Node
(N
)) = N_Allocator
5124 and then Nkind
(Expression
(Original_Node
(N
))) =
5125 N_Qualified_Expression
5126 and then Nkind
(Expression
(Expression
(Original_Node
(N
)))) =
5128 and then Is_Expanded_Build_In_Place_Call
5129 (Expression
(Expression
(Original_Node
(N
))))
5131 null; -- b-i-p function call case
5134 -- An anonymous access discriminant is the definition of a
5137 if Ekind
(Typ
) = E_Anonymous_Access_Type
5138 and then Nkind
(Associated_Node_For_Itype
(Typ
)) =
5139 N_Discriminant_Specification
5142 Discr
: constant Entity_Id
:=
5143 Defining_Identifier
(Associated_Node_For_Itype
(Typ
));
5146 Check_Restriction
(No_Coextensions
, N
);
5148 -- Ada 2012 AI05-0052: If the designated type of the
5149 -- allocator is limited, then the allocator shall not
5150 -- be used to define the value of an access discriminant
5151 -- unless the discriminated type is immutably limited.
5153 if Ada_Version
>= Ada_2012
5154 and then Is_Limited_Type
(Desig_T
)
5155 and then not Is_Limited_View
(Scope
(Discr
))
5158 ("only immutably limited types can have anonymous "
5159 & "access discriminants designating a limited type",
5164 -- Avoid marking an allocator as a dynamic coextension if it is
5165 -- within a static construct.
5167 if not Is_Static_Coextension
(N
) then
5168 Set_Is_Dynamic_Coextension
(N
);
5170 -- Finalization and deallocation of coextensions utilizes an
5171 -- approximate implementation which does not directly adhere
5172 -- to the semantic rules. Warn on potential issues involving
5175 if Is_Controlled
(Desig_T
) then
5177 ("??coextension will not be finalized when its "
5178 & "associated owner is deallocated or finalized", N
);
5181 ("??coextension will not be deallocated when its "
5182 & "associated owner is deallocated", N
);
5186 -- Cleanup for potential static coextensions
5189 Set_Is_Dynamic_Coextension
(N
, False);
5190 Set_Is_Static_Coextension
(N
, False);
5192 -- Anonymous access-to-controlled objects are not finalized on
5193 -- time because this involves run-time ownership and currently
5194 -- this property is not available. In rare cases the object may
5195 -- not be finalized at all. Warn on potential issues involving
5196 -- anonymous access-to-controlled objects.
5198 if Ekind
(Typ
) = E_Anonymous_Access_Type
5199 and then Is_Controlled_Active
(Desig_T
)
5202 ("??object designated by anonymous access object might "
5203 & "not be finalized until its enclosing library unit "
5204 & "goes out of scope", N
);
5205 Error_Msg_N
("\use named access type instead", N
);
5211 -- Report a simple error: if the designated object is a local task,
5212 -- its body has not been seen yet, and its activation will fail an
5213 -- elaboration check.
5215 if Is_Task_Type
(Desig_T
)
5216 and then Scope
(Base_Type
(Desig_T
)) = Current_Scope
5217 and then Is_Compilation_Unit
(Current_Scope
)
5218 and then Ekind
(Current_Scope
) = E_Package
5219 and then not In_Package_Body
(Current_Scope
)
5221 Error_Msg_Warn
:= SPARK_Mode
/= On
;
5222 Error_Msg_N
("cannot activate task before body seen<<", N
);
5223 Error_Msg_N
("\Program_Error [<<", N
);
5226 -- Ada 2012 (AI05-0111-3): Detect an attempt to allocate a task or a
5227 -- type with a task component on a subpool. This action must raise
5228 -- Program_Error at runtime.
5230 if Ada_Version
>= Ada_2012
5231 and then Nkind
(N
) = N_Allocator
5232 and then Present
(Subpool_Handle_Name
(N
))
5233 and then Has_Task
(Desig_T
)
5235 Error_Msg_Warn
:= SPARK_Mode
/= On
;
5236 Error_Msg_N
("cannot allocate task on subpool<<", N
);
5237 Error_Msg_N
("\Program_Error [<<", N
);
5240 Make_Raise_Program_Error
(Sloc
(N
),
5241 Reason
=> PE_Explicit_Raise
));
5244 end Resolve_Allocator
;
5246 ---------------------------
5247 -- Resolve_Arithmetic_Op --
5248 ---------------------------
5250 -- Used for resolving all arithmetic operators except exponentiation
5252 procedure Resolve_Arithmetic_Op
(N
: Node_Id
; Typ
: Entity_Id
) is
5253 L
: constant Node_Id
:= Left_Opnd
(N
);
5254 R
: constant Node_Id
:= Right_Opnd
(N
);
5255 TL
: constant Entity_Id
:= Base_Type
(Etype
(L
));
5256 TR
: constant Entity_Id
:= Base_Type
(Etype
(R
));
5260 B_Typ
: constant Entity_Id
:= Base_Type
(Typ
);
5261 -- We do the resolution using the base type, because intermediate values
5262 -- in expressions always are of the base type, not a subtype of it.
5264 function Expected_Type_Is_Any_Real
(N
: Node_Id
) return Boolean;
5265 -- Returns True if N is in a context that expects "any real type"
5267 function Is_Integer_Or_Universal
(N
: Node_Id
) return Boolean;
5268 -- Return True iff given type is Integer or universal real/integer
5270 procedure Set_Mixed_Mode_Operand
(N
: Node_Id
; T
: Entity_Id
);
5271 -- Choose type of integer literal in fixed-point operation to conform
5272 -- to available fixed-point type. T is the type of the other operand,
5273 -- which is needed to determine the expected type of N.
5275 procedure Set_Operand_Type
(N
: Node_Id
);
5276 -- Set operand type to T if universal
5278 -------------------------------
5279 -- Expected_Type_Is_Any_Real --
5280 -------------------------------
5282 function Expected_Type_Is_Any_Real
(N
: Node_Id
) return Boolean is
5284 -- N is the expression after "delta" in a fixed_point_definition;
5287 return Nkind_In
(Parent
(N
), N_Ordinary_Fixed_Point_Definition
,
5288 N_Decimal_Fixed_Point_Definition
,
5290 -- N is one of the bounds in a real_range_specification;
5293 N_Real_Range_Specification
,
5295 -- N is the expression of a delta_constraint;
5298 N_Delta_Constraint
);
5299 end Expected_Type_Is_Any_Real
;
5301 -----------------------------
5302 -- Is_Integer_Or_Universal --
5303 -----------------------------
5305 function Is_Integer_Or_Universal
(N
: Node_Id
) return Boolean is
5307 Index
: Interp_Index
;
5311 if not Is_Overloaded
(N
) then
5313 return Base_Type
(T
) = Base_Type
(Standard_Integer
)
5314 or else T
= Universal_Integer
5315 or else T
= Universal_Real
;
5317 Get_First_Interp
(N
, Index
, It
);
5318 while Present
(It
.Typ
) loop
5319 if Base_Type
(It
.Typ
) = Base_Type
(Standard_Integer
)
5320 or else It
.Typ
= Universal_Integer
5321 or else It
.Typ
= Universal_Real
5326 Get_Next_Interp
(Index
, It
);
5331 end Is_Integer_Or_Universal
;
5333 ----------------------------
5334 -- Set_Mixed_Mode_Operand --
5335 ----------------------------
5337 procedure Set_Mixed_Mode_Operand
(N
: Node_Id
; T
: Entity_Id
) is
5338 Index
: Interp_Index
;
5342 if Universal_Interpretation
(N
) = Universal_Integer
then
5344 -- A universal integer literal is resolved as standard integer
5345 -- except in the case of a fixed-point result, where we leave it
5346 -- as universal (to be handled by Exp_Fixd later on)
5348 if Is_Fixed_Point_Type
(T
) then
5349 Resolve
(N
, Universal_Integer
);
5351 Resolve
(N
, Standard_Integer
);
5354 elsif Universal_Interpretation
(N
) = Universal_Real
5355 and then (T
= Base_Type
(Standard_Integer
)
5356 or else T
= Universal_Integer
5357 or else T
= Universal_Real
)
5359 -- A universal real can appear in a fixed-type context. We resolve
5360 -- the literal with that context, even though this might raise an
5361 -- exception prematurely (the other operand may be zero).
5365 elsif Etype
(N
) = Base_Type
(Standard_Integer
)
5366 and then T
= Universal_Real
5367 and then Is_Overloaded
(N
)
5369 -- Integer arg in mixed-mode operation. Resolve with universal
5370 -- type, in case preference rule must be applied.
5372 Resolve
(N
, Universal_Integer
);
5375 and then B_Typ
/= Universal_Fixed
5377 -- Not a mixed-mode operation, resolve with context
5381 elsif Etype
(N
) = Any_Fixed
then
5383 -- N may itself be a mixed-mode operation, so use context type
5387 elsif Is_Fixed_Point_Type
(T
)
5388 and then B_Typ
= Universal_Fixed
5389 and then Is_Overloaded
(N
)
5391 -- Must be (fixed * fixed) operation, operand must have one
5392 -- compatible interpretation.
5394 Resolve
(N
, Any_Fixed
);
5396 elsif Is_Fixed_Point_Type
(B_Typ
)
5397 and then (T
= Universal_Real
or else Is_Fixed_Point_Type
(T
))
5398 and then Is_Overloaded
(N
)
5400 -- C * F(X) in a fixed context, where C is a real literal or a
5401 -- fixed-point expression. F must have either a fixed type
5402 -- interpretation or an integer interpretation, but not both.
5404 Get_First_Interp
(N
, Index
, It
);
5405 while Present
(It
.Typ
) loop
5406 if Base_Type
(It
.Typ
) = Base_Type
(Standard_Integer
) then
5407 if Analyzed
(N
) then
5408 Error_Msg_N
("ambiguous operand in fixed operation", N
);
5410 Resolve
(N
, Standard_Integer
);
5413 elsif Is_Fixed_Point_Type
(It
.Typ
) then
5414 if Analyzed
(N
) then
5415 Error_Msg_N
("ambiguous operand in fixed operation", N
);
5417 Resolve
(N
, It
.Typ
);
5421 Get_Next_Interp
(Index
, It
);
5424 -- Reanalyze the literal with the fixed type of the context. If
5425 -- context is Universal_Fixed, we are within a conversion, leave
5426 -- the literal as a universal real because there is no usable
5427 -- fixed type, and the target of the conversion plays no role in
5441 if B_Typ
= Universal_Fixed
5442 and then Nkind
(Op2
) = N_Real_Literal
5444 T2
:= Universal_Real
;
5449 Set_Analyzed
(Op2
, False);
5453 -- A universal real conditional expression can appear in a fixed-type
5454 -- context and must be resolved with that context to facilitate the
5455 -- code generation to the backend.
5457 elsif Nkind_In
(N
, N_Case_Expression
, N_If_Expression
)
5458 and then Etype
(N
) = Universal_Real
5459 and then Is_Fixed_Point_Type
(B_Typ
)
5466 end Set_Mixed_Mode_Operand
;
5468 ----------------------
5469 -- Set_Operand_Type --
5470 ----------------------
5472 procedure Set_Operand_Type
(N
: Node_Id
) is
5474 if Etype
(N
) = Universal_Integer
5475 or else Etype
(N
) = Universal_Real
5479 end Set_Operand_Type
;
5481 -- Start of processing for Resolve_Arithmetic_Op
5484 if Comes_From_Source
(N
)
5485 and then Ekind
(Entity
(N
)) = E_Function
5486 and then Is_Imported
(Entity
(N
))
5487 and then Is_Intrinsic_Subprogram
(Entity
(N
))
5489 Resolve_Intrinsic_Operator
(N
, Typ
);
5492 -- Special-case for mixed-mode universal expressions or fixed point type
5493 -- operation: each argument is resolved separately. The same treatment
5494 -- is required if one of the operands of a fixed point operation is
5495 -- universal real, since in this case we don't do a conversion to a
5496 -- specific fixed-point type (instead the expander handles the case).
5498 -- Set the type of the node to its universal interpretation because
5499 -- legality checks on an exponentiation operand need the context.
5501 elsif (B_Typ
= Universal_Integer
or else B_Typ
= Universal_Real
)
5502 and then Present
(Universal_Interpretation
(L
))
5503 and then Present
(Universal_Interpretation
(R
))
5505 Set_Etype
(N
, B_Typ
);
5506 Resolve
(L
, Universal_Interpretation
(L
));
5507 Resolve
(R
, Universal_Interpretation
(R
));
5509 elsif (B_Typ
= Universal_Real
5510 or else Etype
(N
) = Universal_Fixed
5511 or else (Etype
(N
) = Any_Fixed
5512 and then Is_Fixed_Point_Type
(B_Typ
))
5513 or else (Is_Fixed_Point_Type
(B_Typ
)
5514 and then (Is_Integer_Or_Universal
(L
)
5516 Is_Integer_Or_Universal
(R
))))
5517 and then Nkind_In
(N
, N_Op_Multiply
, N_Op_Divide
)
5519 if TL
= Universal_Integer
or else TR
= Universal_Integer
then
5520 Check_For_Visible_Operator
(N
, B_Typ
);
5523 -- If context is a fixed type and one operand is integer, the other
5524 -- is resolved with the type of the context.
5526 if Is_Fixed_Point_Type
(B_Typ
)
5527 and then (Base_Type
(TL
) = Base_Type
(Standard_Integer
)
5528 or else TL
= Universal_Integer
)
5533 elsif Is_Fixed_Point_Type
(B_Typ
)
5534 and then (Base_Type
(TR
) = Base_Type
(Standard_Integer
)
5535 or else TR
= Universal_Integer
)
5540 -- If both operands are universal and the context is a floating
5541 -- point type, the operands are resolved to the type of the context.
5543 elsif Is_Floating_Point_Type
(B_Typ
) then
5548 Set_Mixed_Mode_Operand
(L
, TR
);
5549 Set_Mixed_Mode_Operand
(R
, TL
);
5552 -- Check the rule in RM05-4.5.5(19.1/2) disallowing universal_fixed
5553 -- multiplying operators from being used when the expected type is
5554 -- also universal_fixed. Note that B_Typ will be Universal_Fixed in
5555 -- some cases where the expected type is actually Any_Real;
5556 -- Expected_Type_Is_Any_Real takes care of that case.
5558 if Etype
(N
) = Universal_Fixed
5559 or else Etype
(N
) = Any_Fixed
5561 if B_Typ
= Universal_Fixed
5562 and then not Expected_Type_Is_Any_Real
(N
)
5563 and then not Nkind_In
(Parent
(N
), N_Type_Conversion
,
5564 N_Unchecked_Type_Conversion
)
5566 Error_Msg_N
("type cannot be determined from context!", N
);
5567 Error_Msg_N
("\explicit conversion to result type required", N
);
5569 Set_Etype
(L
, Any_Type
);
5570 Set_Etype
(R
, Any_Type
);
5573 if Ada_Version
= Ada_83
5574 and then Etype
(N
) = Universal_Fixed
5576 Nkind_In
(Parent
(N
), N_Type_Conversion
,
5577 N_Unchecked_Type_Conversion
)
5580 ("(Ada 83) fixed-point operation needs explicit "
5584 -- The expected type is "any real type" in contexts like
5586 -- type T is delta <universal_fixed-expression> ...
5588 -- in which case we need to set the type to Universal_Real
5589 -- so that static expression evaluation will work properly.
5591 if Expected_Type_Is_Any_Real
(N
) then
5592 Set_Etype
(N
, Universal_Real
);
5594 Set_Etype
(N
, B_Typ
);
5598 elsif Is_Fixed_Point_Type
(B_Typ
)
5599 and then (Is_Integer_Or_Universal
(L
)
5600 or else Nkind
(L
) = N_Real_Literal
5601 or else Nkind
(R
) = N_Real_Literal
5602 or else Is_Integer_Or_Universal
(R
))
5604 Set_Etype
(N
, B_Typ
);
5606 elsif Etype
(N
) = Any_Fixed
then
5608 -- If no previous errors, this is only possible if one operand is
5609 -- overloaded and the context is universal. Resolve as such.
5611 Set_Etype
(N
, B_Typ
);
5615 if (TL
= Universal_Integer
or else TL
= Universal_Real
)
5617 (TR
= Universal_Integer
or else TR
= Universal_Real
)
5619 Check_For_Visible_Operator
(N
, B_Typ
);
5622 -- If the context is Universal_Fixed and the operands are also
5623 -- universal fixed, this is an error, unless there is only one
5624 -- applicable fixed_point type (usually Duration).
5626 if B_Typ
= Universal_Fixed
and then Etype
(L
) = Universal_Fixed
then
5627 T
:= Unique_Fixed_Point_Type
(N
);
5629 if T
= Any_Type
then
5642 -- If one of the arguments was resolved to a non-universal type.
5643 -- label the result of the operation itself with the same type.
5644 -- Do the same for the universal argument, if any.
5646 T
:= Intersect_Types
(L
, R
);
5647 Set_Etype
(N
, Base_Type
(T
));
5648 Set_Operand_Type
(L
);
5649 Set_Operand_Type
(R
);
5652 Generate_Operator_Reference
(N
, Typ
);
5653 Analyze_Dimension
(N
);
5654 Eval_Arithmetic_Op
(N
);
5656 -- In SPARK, a multiplication or division with operands of fixed point
5657 -- types must be qualified or explicitly converted to identify the
5660 if (Is_Fixed_Point_Type
(Etype
(L
))
5661 or else Is_Fixed_Point_Type
(Etype
(R
)))
5662 and then Nkind_In
(N
, N_Op_Multiply
, N_Op_Divide
)
5664 not Nkind_In
(Parent
(N
), N_Qualified_Expression
, N_Type_Conversion
)
5666 Check_SPARK_05_Restriction
5667 ("operation should be qualified or explicitly converted", N
);
5670 -- Set overflow and division checking bit
5672 if Nkind
(N
) in N_Op
then
5673 if not Overflow_Checks_Suppressed
(Etype
(N
)) then
5674 Enable_Overflow_Check
(N
);
5677 -- Give warning if explicit division by zero
5679 if Nkind_In
(N
, N_Op_Divide
, N_Op_Rem
, N_Op_Mod
)
5680 and then not Division_Checks_Suppressed
(Etype
(N
))
5682 Rop
:= Right_Opnd
(N
);
5684 if Compile_Time_Known_Value
(Rop
)
5685 and then ((Is_Integer_Type
(Etype
(Rop
))
5686 and then Expr_Value
(Rop
) = Uint_0
)
5688 (Is_Real_Type
(Etype
(Rop
))
5689 and then Expr_Value_R
(Rop
) = Ureal_0
))
5691 -- Specialize the warning message according to the operation.
5692 -- When SPARK_Mode is On, force a warning instead of an error
5693 -- in that case, as this likely corresponds to deactivated
5694 -- code. The following warnings are for the case
5699 -- For division, we have two cases, for float division
5700 -- of an unconstrained float type, on a machine where
5701 -- Machine_Overflows is false, we don't get an exception
5702 -- at run-time, but rather an infinity or Nan. The Nan
5703 -- case is pretty obscure, so just warn about infinities.
5705 if Is_Floating_Point_Type
(Typ
)
5706 and then not Is_Constrained
(Typ
)
5707 and then not Machine_Overflows_On_Target
5710 ("float division by zero, may generate "
5711 & "'+'/'- infinity??", Right_Opnd
(N
));
5713 -- For all other cases, we get a Constraint_Error
5716 Apply_Compile_Time_Constraint_Error
5717 (N
, "division by zero??", CE_Divide_By_Zero
,
5718 Loc
=> Sloc
(Right_Opnd
(N
)),
5719 Warn
=> SPARK_Mode
= On
);
5723 Apply_Compile_Time_Constraint_Error
5724 (N
, "rem with zero divisor??", CE_Divide_By_Zero
,
5725 Loc
=> Sloc
(Right_Opnd
(N
)),
5726 Warn
=> SPARK_Mode
= On
);
5729 Apply_Compile_Time_Constraint_Error
5730 (N
, "mod with zero divisor??", CE_Divide_By_Zero
,
5731 Loc
=> Sloc
(Right_Opnd
(N
)),
5732 Warn
=> SPARK_Mode
= On
);
5734 -- Division by zero can only happen with division, rem,
5735 -- and mod operations.
5738 raise Program_Error
;
5741 -- In GNATprove mode, we enable the division check so that
5742 -- GNATprove will issue a message if it cannot be proved.
5744 if GNATprove_Mode
then
5745 Activate_Division_Check
(N
);
5748 -- Otherwise just set the flag to check at run time
5751 Activate_Division_Check
(N
);
5755 -- If Restriction No_Implicit_Conditionals is active, then it is
5756 -- violated if either operand can be negative for mod, or for rem
5757 -- if both operands can be negative.
5759 if Restriction_Check_Required
(No_Implicit_Conditionals
)
5760 and then Nkind_In
(N
, N_Op_Rem
, N_Op_Mod
)
5769 -- Set if corresponding operand might be negative
5773 (Left_Opnd
(N
), OK
, Lo
, Hi
, Assume_Valid
=> True);
5774 LNeg
:= (not OK
) or else Lo
< 0;
5777 (Right_Opnd
(N
), OK
, Lo
, Hi
, Assume_Valid
=> True);
5778 RNeg
:= (not OK
) or else Lo
< 0;
5780 -- Check if we will be generating conditionals. There are two
5781 -- cases where that can happen, first for REM, the only case
5782 -- is largest negative integer mod -1, where the division can
5783 -- overflow, but we still have to give the right result. The
5784 -- front end generates a test for this annoying case. Here we
5785 -- just test if both operands can be negative (that's what the
5786 -- expander does, so we match its logic here).
5788 -- The second case is mod where either operand can be negative.
5789 -- In this case, the back end has to generate additional tests.
5791 if (Nkind
(N
) = N_Op_Rem
and then (LNeg
and RNeg
))
5793 (Nkind
(N
) = N_Op_Mod
and then (LNeg
or RNeg
))
5795 Check_Restriction
(No_Implicit_Conditionals
, N
);
5801 Check_Unset_Reference
(L
);
5802 Check_Unset_Reference
(R
);
5803 end Resolve_Arithmetic_Op
;
5809 procedure Resolve_Call
(N
: Node_Id
; Typ
: Entity_Id
) is
5810 function Same_Or_Aliased_Subprograms
5812 E
: Entity_Id
) return Boolean;
5813 -- Returns True if the subprogram entity S is the same as E or else
5814 -- S is an alias of E.
5816 ---------------------------------
5817 -- Same_Or_Aliased_Subprograms --
5818 ---------------------------------
5820 function Same_Or_Aliased_Subprograms
5822 E
: Entity_Id
) return Boolean
5824 Subp_Alias
: constant Entity_Id
:= Alias
(S
);
5826 return S
= E
or else (Present
(Subp_Alias
) and then Subp_Alias
= E
);
5827 end Same_Or_Aliased_Subprograms
;
5831 Loc
: constant Source_Ptr
:= Sloc
(N
);
5832 Subp
: constant Node_Id
:= Name
(N
);
5833 Body_Id
: Entity_Id
;
5843 -- Start of processing for Resolve_Call
5846 -- Preserve relevant elaboration-related attributes of the context which
5847 -- are no longer available or very expensive to recompute once analysis,
5848 -- resolution, and expansion are over.
5850 Mark_Elaboration_Attributes
5856 -- The context imposes a unique interpretation with type Typ on a
5857 -- procedure or function call. Find the entity of the subprogram that
5858 -- yields the expected type, and propagate the corresponding formal
5859 -- constraints on the actuals. The caller has established that an
5860 -- interpretation exists, and emitted an error if not unique.
5862 -- First deal with the case of a call to an access-to-subprogram,
5863 -- dereference made explicit in Analyze_Call.
5865 if Ekind
(Etype
(Subp
)) = E_Subprogram_Type
then
5866 if not Is_Overloaded
(Subp
) then
5867 Nam
:= Etype
(Subp
);
5870 -- Find the interpretation whose type (a subprogram type) has a
5871 -- return type that is compatible with the context. Analysis of
5872 -- the node has established that one exists.
5876 Get_First_Interp
(Subp
, I
, It
);
5877 while Present
(It
.Typ
) loop
5878 if Covers
(Typ
, Etype
(It
.Typ
)) then
5883 Get_Next_Interp
(I
, It
);
5887 raise Program_Error
;
5891 -- If the prefix is not an entity, then resolve it
5893 if not Is_Entity_Name
(Subp
) then
5894 Resolve
(Subp
, Nam
);
5897 -- For an indirect call, we always invalidate checks, since we do not
5898 -- know whether the subprogram is local or global. Yes we could do
5899 -- better here, e.g. by knowing that there are no local subprograms,
5900 -- but it does not seem worth the effort. Similarly, we kill all
5901 -- knowledge of current constant values.
5903 Kill_Current_Values
;
5905 -- If this is a procedure call which is really an entry call, do
5906 -- the conversion of the procedure call to an entry call. Protected
5907 -- operations use the same circuitry because the name in the call
5908 -- can be an arbitrary expression with special resolution rules.
5910 elsif Nkind_In
(Subp
, N_Selected_Component
, N_Indexed_Component
)
5911 or else (Is_Entity_Name
(Subp
)
5912 and then Ekind_In
(Entity
(Subp
), E_Entry
, E_Entry_Family
))
5914 Resolve_Entry_Call
(N
, Typ
);
5916 if Legacy_Elaboration_Checks
then
5917 Check_Elab_Call
(N
);
5920 -- Annotate the tree by creating a call marker in case the original
5921 -- call is transformed by expansion. The call marker is automatically
5922 -- saved for later examination by the ABE Processing phase.
5924 Build_Call_Marker
(N
);
5926 -- Kill checks and constant values, as above for indirect case
5927 -- Who knows what happens when another task is activated?
5929 Kill_Current_Values
;
5932 -- Normal subprogram call with name established in Resolve
5934 elsif not (Is_Type
(Entity
(Subp
))) then
5935 Nam
:= Entity
(Subp
);
5936 Set_Entity_With_Checks
(Subp
, Nam
);
5938 -- Otherwise we must have the case of an overloaded call
5941 pragma Assert
(Is_Overloaded
(Subp
));
5943 -- Initialize Nam to prevent warning (we know it will be assigned
5944 -- in the loop below, but the compiler does not know that).
5948 Get_First_Interp
(Subp
, I
, It
);
5949 while Present
(It
.Typ
) loop
5950 if Covers
(Typ
, It
.Typ
) then
5952 Set_Entity_With_Checks
(Subp
, Nam
);
5956 Get_Next_Interp
(I
, It
);
5960 if Is_Access_Subprogram_Type
(Base_Type
(Etype
(Nam
)))
5961 and then not Is_Access_Subprogram_Type
(Base_Type
(Typ
))
5962 and then Nkind
(Subp
) /= N_Explicit_Dereference
5963 and then Present
(Parameter_Associations
(N
))
5965 -- The prefix is a parameterless function call that returns an access
5966 -- to subprogram. If parameters are present in the current call, add
5967 -- add an explicit dereference. We use the base type here because
5968 -- within an instance these may be subtypes.
5970 -- The dereference is added either in Analyze_Call or here. Should
5971 -- be consolidated ???
5973 Set_Is_Overloaded
(Subp
, False);
5974 Set_Etype
(Subp
, Etype
(Nam
));
5975 Insert_Explicit_Dereference
(Subp
);
5976 Nam
:= Designated_Type
(Etype
(Nam
));
5977 Resolve
(Subp
, Nam
);
5980 -- Check that a call to Current_Task does not occur in an entry body
5982 if Is_RTE
(Nam
, RE_Current_Task
) then
5991 -- Exclude calls that occur within the default of a formal
5992 -- parameter of the entry, since those are evaluated outside
5995 exit when No
(P
) or else Nkind
(P
) = N_Parameter_Specification
;
5997 if Nkind
(P
) = N_Entry_Body
5998 or else (Nkind
(P
) = N_Subprogram_Body
5999 and then Is_Entry_Barrier_Function
(P
))
6002 Error_Msg_Warn
:= SPARK_Mode
/= On
;
6004 ("& should not be used in entry body (RM C.7(17))<<",
6006 Error_Msg_NE
("\Program_Error [<<", N
, Nam
);
6008 Make_Raise_Program_Error
(Loc
,
6009 Reason
=> PE_Current_Task_In_Entry_Body
));
6010 Set_Etype
(N
, Rtype
);
6017 -- Check that a procedure call does not occur in the context of the
6018 -- entry call statement of a conditional or timed entry call. Note that
6019 -- the case of a call to a subprogram renaming of an entry will also be
6020 -- rejected. The test for N not being an N_Entry_Call_Statement is
6021 -- defensive, covering the possibility that the processing of entry
6022 -- calls might reach this point due to later modifications of the code
6025 if Nkind
(Parent
(N
)) = N_Entry_Call_Alternative
6026 and then Nkind
(N
) /= N_Entry_Call_Statement
6027 and then Entry_Call_Statement
(Parent
(N
)) = N
6029 if Ada_Version
< Ada_2005
then
6030 Error_Msg_N
("entry call required in select statement", N
);
6032 -- Ada 2005 (AI-345): If a procedure_call_statement is used
6033 -- for a procedure_or_entry_call, the procedure_name or
6034 -- procedure_prefix of the procedure_call_statement shall denote
6035 -- an entry renamed by a procedure, or (a view of) a primitive
6036 -- subprogram of a limited interface whose first parameter is
6037 -- a controlling parameter.
6039 elsif Nkind
(N
) = N_Procedure_Call_Statement
6040 and then not Is_Renamed_Entry
(Nam
)
6041 and then not Is_Controlling_Limited_Procedure
(Nam
)
6044 ("entry call or dispatching primitive of interface required", N
);
6048 -- If the SPARK_05 restriction is active, we are not allowed
6049 -- to have a call to a subprogram before we see its completion.
6051 if not Has_Completion
(Nam
)
6052 and then Restriction_Check_Required
(SPARK_05
)
6054 -- Don't flag strange internal calls
6056 and then Comes_From_Source
(N
)
6057 and then Comes_From_Source
(Nam
)
6059 -- Only flag calls in extended main source
6061 and then In_Extended_Main_Source_Unit
(Nam
)
6062 and then In_Extended_Main_Source_Unit
(N
)
6064 -- Exclude enumeration literals from this processing
6066 and then Ekind
(Nam
) /= E_Enumeration_Literal
6068 Check_SPARK_05_Restriction
6069 ("call to subprogram cannot appear before its body", N
);
6072 -- Check that this is not a call to a protected procedure or entry from
6073 -- within a protected function.
6075 Check_Internal_Protected_Use
(N
, Nam
);
6077 -- Freeze the subprogram name if not in a spec-expression. Note that
6078 -- we freeze procedure calls as well as function calls. Procedure calls
6079 -- are not frozen according to the rules (RM 13.14(14)) because it is
6080 -- impossible to have a procedure call to a non-frozen procedure in
6081 -- pure Ada, but in the code that we generate in the expander, this
6082 -- rule needs extending because we can generate procedure calls that
6085 -- In Ada 2012, expression functions may be called within pre/post
6086 -- conditions of subsequent functions or expression functions. Such
6087 -- calls do not freeze when they appear within generated bodies,
6088 -- (including the body of another expression function) which would
6089 -- place the freeze node in the wrong scope. An expression function
6090 -- is frozen in the usual fashion, by the appearance of a real body,
6091 -- or at the end of a declarative part.
6093 if Is_Entity_Name
(Subp
)
6094 and then not In_Spec_Expression
6095 and then not Is_Expression_Function_Or_Completion
(Current_Scope
)
6097 (not Is_Expression_Function_Or_Completion
(Entity
(Subp
))
6098 or else Scope
(Entity
(Subp
)) = Current_Scope
)
6100 Freeze_Expression
(Subp
);
6103 -- For a predefined operator, the type of the result is the type imposed
6104 -- by context, except for a predefined operation on universal fixed.
6105 -- Otherwise The type of the call is the type returned by the subprogram
6108 if Is_Predefined_Op
(Nam
) then
6109 if Etype
(N
) /= Universal_Fixed
then
6113 -- If the subprogram returns an array type, and the context requires the
6114 -- component type of that array type, the node is really an indexing of
6115 -- the parameterless call. Resolve as such. A pathological case occurs
6116 -- when the type of the component is an access to the array type. In
6117 -- this case the call is truly ambiguous. If the call is to an intrinsic
6118 -- subprogram, it can't be an indexed component. This check is necessary
6119 -- because if it's Unchecked_Conversion, and we have "type T_Ptr is
6120 -- access T;" and "type T is array (...) of T_Ptr;" (i.e. an array of
6121 -- pointers to the same array), the compiler gets confused and does an
6122 -- infinite recursion.
6124 elsif (Needs_No_Actuals
(Nam
) or else Needs_One_Actual
(Nam
))
6126 ((Is_Array_Type
(Etype
(Nam
))
6127 and then Covers
(Typ
, Component_Type
(Etype
(Nam
))))
6129 (Is_Access_Type
(Etype
(Nam
))
6130 and then Is_Array_Type
(Designated_Type
(Etype
(Nam
)))
6132 Covers
(Typ
, Component_Type
(Designated_Type
(Etype
(Nam
))))
6133 and then not Is_Intrinsic_Subprogram
(Entity
(Subp
))))
6136 Index_Node
: Node_Id
;
6138 Ret_Type
: constant Entity_Id
:= Etype
(Nam
);
6141 if Is_Access_Type
(Ret_Type
)
6142 and then Ret_Type
= Component_Type
(Designated_Type
(Ret_Type
))
6145 ("cannot disambiguate function call and indexing", N
);
6147 New_Subp
:= Relocate_Node
(Subp
);
6149 -- The called entity may be an explicit dereference, in which
6150 -- case there is no entity to set.
6152 if Nkind
(New_Subp
) /= N_Explicit_Dereference
then
6153 Set_Entity
(Subp
, Nam
);
6156 if (Is_Array_Type
(Ret_Type
)
6157 and then Component_Type
(Ret_Type
) /= Any_Type
)
6159 (Is_Access_Type
(Ret_Type
)
6161 Component_Type
(Designated_Type
(Ret_Type
)) /= Any_Type
)
6163 if Needs_No_Actuals
(Nam
) then
6165 -- Indexed call to a parameterless function
6168 Make_Indexed_Component
(Loc
,
6170 Make_Function_Call
(Loc
, Name
=> New_Subp
),
6171 Expressions
=> Parameter_Associations
(N
));
6173 -- An Ada 2005 prefixed call to a primitive operation
6174 -- whose first parameter is the prefix. This prefix was
6175 -- prepended to the parameter list, which is actually a
6176 -- list of indexes. Remove the prefix in order to build
6177 -- the proper indexed component.
6180 Make_Indexed_Component
(Loc
,
6182 Make_Function_Call
(Loc
,
6184 Parameter_Associations
=>
6186 (Remove_Head
(Parameter_Associations
(N
)))),
6187 Expressions
=> Parameter_Associations
(N
));
6190 -- Preserve the parenthesis count of the node
6192 Set_Paren_Count
(Index_Node
, Paren_Count
(N
));
6194 -- Since we are correcting a node classification error made
6195 -- by the parser, we call Replace rather than Rewrite.
6197 Replace
(N
, Index_Node
);
6199 Set_Etype
(Prefix
(N
), Ret_Type
);
6201 Resolve_Indexed_Component
(N
, Typ
);
6203 if Legacy_Elaboration_Checks
then
6204 Check_Elab_Call
(Prefix
(N
));
6207 -- Annotate the tree by creating a call marker in case
6208 -- the original call is transformed by expansion. The call
6209 -- marker is automatically saved for later examination by
6210 -- the ABE Processing phase.
6212 Build_Call_Marker
(Prefix
(N
));
6220 -- If the called function is not declared in the main unit and it
6221 -- returns the limited view of type then use the available view (as
6222 -- is done in Try_Object_Operation) to prevent back-end confusion;
6223 -- for the function entity itself. The call must appear in a context
6224 -- where the nonlimited view is available. If the function entity is
6225 -- in the extended main unit then no action is needed, because the
6226 -- back end handles this case. In either case the type of the call
6227 -- is the nonlimited view.
6229 if From_Limited_With
(Etype
(Nam
))
6230 and then Present
(Available_View
(Etype
(Nam
)))
6232 Set_Etype
(N
, Available_View
(Etype
(Nam
)));
6234 if not In_Extended_Main_Code_Unit
(Nam
) then
6235 Set_Etype
(Nam
, Available_View
(Etype
(Nam
)));
6239 Set_Etype
(N
, Etype
(Nam
));
6243 -- In the case where the call is to an overloaded subprogram, Analyze
6244 -- calls Normalize_Actuals once per overloaded subprogram. Therefore in
6245 -- such a case Normalize_Actuals needs to be called once more to order
6246 -- the actuals correctly. Otherwise the call will have the ordering
6247 -- given by the last overloaded subprogram whether this is the correct
6248 -- one being called or not.
6250 if Is_Overloaded
(Subp
) then
6251 Normalize_Actuals
(N
, Nam
, False, Norm_OK
);
6252 pragma Assert
(Norm_OK
);
6255 -- In any case, call is fully resolved now. Reset Overload flag, to
6256 -- prevent subsequent overload resolution if node is analyzed again
6258 Set_Is_Overloaded
(Subp
, False);
6259 Set_Is_Overloaded
(N
, False);
6261 -- A Ghost entity must appear in a specific context
6263 if Is_Ghost_Entity
(Nam
) and then Comes_From_Source
(N
) then
6264 Check_Ghost_Context
(Nam
, N
);
6267 -- If we are calling the current subprogram from immediately within its
6268 -- body, then that is the case where we can sometimes detect cases of
6269 -- infinite recursion statically. Do not try this in case restriction
6270 -- No_Recursion is in effect anyway, and do it only for source calls.
6272 if Comes_From_Source
(N
) then
6273 Scop
:= Current_Scope
;
6275 -- Check violation of SPARK_05 restriction which does not permit
6276 -- a subprogram body to contain a call to the subprogram directly.
6278 if Restriction_Check_Required
(SPARK_05
)
6279 and then Same_Or_Aliased_Subprograms
(Nam
, Scop
)
6281 Check_SPARK_05_Restriction
6282 ("subprogram may not contain direct call to itself", N
);
6285 -- Issue warning for possible infinite recursion in the absence
6286 -- of the No_Recursion restriction.
6288 if Same_Or_Aliased_Subprograms
(Nam
, Scop
)
6289 and then not Restriction_Active
(No_Recursion
)
6290 and then Check_Infinite_Recursion
(N
)
6292 -- Here we detected and flagged an infinite recursion, so we do
6293 -- not need to test the case below for further warnings. Also we
6294 -- are all done if we now have a raise SE node.
6296 if Nkind
(N
) = N_Raise_Storage_Error
then
6300 -- If call is to immediately containing subprogram, then check for
6301 -- the case of a possible run-time detectable infinite recursion.
6304 Scope_Loop
: while Scop
/= Standard_Standard
loop
6305 if Same_Or_Aliased_Subprograms
(Nam
, Scop
) then
6307 -- Although in general case, recursion is not statically
6308 -- checkable, the case of calling an immediately containing
6309 -- subprogram is easy to catch.
6311 Check_Restriction
(No_Recursion
, N
);
6313 -- If the recursive call is to a parameterless subprogram,
6314 -- then even if we can't statically detect infinite
6315 -- recursion, this is pretty suspicious, and we output a
6316 -- warning. Furthermore, we will try later to detect some
6317 -- cases here at run time by expanding checking code (see
6318 -- Detect_Infinite_Recursion in package Exp_Ch6).
6320 -- If the recursive call is within a handler, do not emit a
6321 -- warning, because this is a common idiom: loop until input
6322 -- is correct, catch illegal input in handler and restart.
6324 if No
(First_Formal
(Nam
))
6325 and then Etype
(Nam
) = Standard_Void_Type
6326 and then not Error_Posted
(N
)
6327 and then Nkind
(Parent
(N
)) /= N_Exception_Handler
6329 -- For the case of a procedure call. We give the message
6330 -- only if the call is the first statement in a sequence
6331 -- of statements, or if all previous statements are
6332 -- simple assignments. This is simply a heuristic to
6333 -- decrease false positives, without losing too many good
6334 -- warnings. The idea is that these previous statements
6335 -- may affect global variables the procedure depends on.
6336 -- We also exclude raise statements, that may arise from
6337 -- constraint checks and are probably unrelated to the
6338 -- intended control flow.
6340 if Nkind
(N
) = N_Procedure_Call_Statement
6341 and then Is_List_Member
(N
)
6347 while Present
(P
) loop
6348 if not Nkind_In
(P
, N_Assignment_Statement
,
6349 N_Raise_Constraint_Error
)
6359 -- Do not give warning if we are in a conditional context
6362 K
: constant Node_Kind
:= Nkind
(Parent
(N
));
6364 if (K
= N_Loop_Statement
6365 and then Present
(Iteration_Scheme
(Parent
(N
))))
6366 or else K
= N_If_Statement
6367 or else K
= N_Elsif_Part
6368 or else K
= N_Case_Statement_Alternative
6374 -- Here warning is to be issued
6376 Set_Has_Recursive_Call
(Nam
);
6377 Error_Msg_Warn
:= SPARK_Mode
/= On
;
6378 Error_Msg_N
("possible infinite recursion<<!", N
);
6379 Error_Msg_N
("\Storage_Error ]<<!", N
);
6385 Scop
:= Scope
(Scop
);
6386 end loop Scope_Loop
;
6390 -- Check obsolescent reference to Ada.Characters.Handling subprogram
6392 Check_Obsolescent_2005_Entity
(Nam
, Subp
);
6394 -- If subprogram name is a predefined operator, it was given in
6395 -- functional notation. Replace call node with operator node, so
6396 -- that actuals can be resolved appropriately.
6398 if Is_Predefined_Op
(Nam
) or else Ekind
(Nam
) = E_Operator
then
6399 Make_Call_Into_Operator
(N
, Typ
, Entity
(Name
(N
)));
6402 elsif Present
(Alias
(Nam
))
6403 and then Is_Predefined_Op
(Alias
(Nam
))
6405 Resolve_Actuals
(N
, Nam
);
6406 Make_Call_Into_Operator
(N
, Typ
, Alias
(Nam
));
6410 -- Create a transient scope if the resulting type requires it
6412 -- There are several notable exceptions:
6414 -- a) In init procs, the transient scope overhead is not needed, and is
6415 -- even incorrect when the call is a nested initialization call for a
6416 -- component whose expansion may generate adjust calls. However, if the
6417 -- call is some other procedure call within an initialization procedure
6418 -- (for example a call to Create_Task in the init_proc of the task
6419 -- run-time record) a transient scope must be created around this call.
6421 -- b) Enumeration literal pseudo-calls need no transient scope
6423 -- c) Intrinsic subprograms (Unchecked_Conversion and source info
6424 -- functions) do not use the secondary stack even though the return
6425 -- type may be unconstrained.
6427 -- d) Calls to a build-in-place function, since such functions may
6428 -- allocate their result directly in a target object, and cases where
6429 -- the result does get allocated in the secondary stack are checked for
6430 -- within the specialized Exp_Ch6 procedures for expanding those
6431 -- build-in-place calls.
6433 -- e) Calls to inlinable expression functions do not use the secondary
6434 -- stack (since the call will be replaced by its returned object).
6436 -- f) If the subprogram is marked Inline_Always, then even if it returns
6437 -- an unconstrained type the call does not require use of the secondary
6438 -- stack. However, inlining will only take place if the body to inline
6439 -- is already present. It may not be available if e.g. the subprogram is
6440 -- declared in a child instance.
6442 -- If this is an initialization call for a type whose construction
6443 -- uses the secondary stack, and it is not a nested call to initialize
6444 -- a component, we do need to create a transient scope for it. We
6445 -- check for this by traversing the type in Check_Initialization_Call.
6448 and then Has_Pragma_Inline
(Nam
)
6449 and then Nkind
(Unit_Declaration_Node
(Nam
)) = N_Subprogram_Declaration
6450 and then Present
(Body_To_Inline
(Unit_Declaration_Node
(Nam
)))
6454 elsif Ekind
(Nam
) = E_Enumeration_Literal
6455 or else Is_Build_In_Place_Function
(Nam
)
6456 or else Is_Intrinsic_Subprogram
(Nam
)
6457 or else Is_Inlinable_Expression_Function
(Nam
)
6461 elsif Expander_Active
6462 and then Is_Type
(Etype
(Nam
))
6463 and then Requires_Transient_Scope
(Etype
(Nam
))
6465 (not Within_Init_Proc
6467 (not Is_Init_Proc
(Nam
) and then Ekind
(Nam
) /= E_Function
))
6469 Establish_Transient_Scope
(N
, Sec_Stack
=> True);
6471 -- If the call appears within the bounds of a loop, it will
6472 -- be rewritten and reanalyzed, nothing left to do here.
6474 if Nkind
(N
) /= N_Function_Call
then
6478 elsif Is_Init_Proc
(Nam
)
6479 and then not Within_Init_Proc
6481 Check_Initialization_Call
(N
, Nam
);
6484 -- A protected function cannot be called within the definition of the
6485 -- enclosing protected type, unless it is part of a pre/postcondition
6486 -- on another protected operation. This may appear in the entry wrapper
6487 -- created for an entry with preconditions.
6489 if Is_Protected_Type
(Scope
(Nam
))
6490 and then In_Open_Scopes
(Scope
(Nam
))
6491 and then not Has_Completion
(Scope
(Nam
))
6492 and then not In_Spec_Expression
6493 and then not Is_Entry_Wrapper
(Current_Scope
)
6496 ("& cannot be called before end of protected definition", N
, Nam
);
6499 -- Propagate interpretation to actuals, and add default expressions
6502 if Present
(First_Formal
(Nam
)) then
6503 Resolve_Actuals
(N
, Nam
);
6505 -- Overloaded literals are rewritten as function calls, for purpose of
6506 -- resolution. After resolution, we can replace the call with the
6509 elsif Ekind
(Nam
) = E_Enumeration_Literal
then
6510 Copy_Node
(Subp
, N
);
6511 Resolve_Entity_Name
(N
, Typ
);
6513 -- Avoid validation, since it is a static function call
6515 Generate_Reference
(Nam
, Subp
);
6519 -- If the subprogram is not global, then kill all saved values and
6520 -- checks. This is a bit conservative, since in many cases we could do
6521 -- better, but it is not worth the effort. Similarly, we kill constant
6522 -- values. However we do not need to do this for internal entities
6523 -- (unless they are inherited user-defined subprograms), since they
6524 -- are not in the business of molesting local values.
6526 -- If the flag Suppress_Value_Tracking_On_Calls is set, then we also
6527 -- kill all checks and values for calls to global subprograms. This
6528 -- takes care of the case where an access to a local subprogram is
6529 -- taken, and could be passed directly or indirectly and then called
6530 -- from almost any context.
6532 -- Note: we do not do this step till after resolving the actuals. That
6533 -- way we still take advantage of the current value information while
6534 -- scanning the actuals.
6536 -- We suppress killing values if we are processing the nodes associated
6537 -- with N_Freeze_Entity nodes. Otherwise the declaration of a tagged
6538 -- type kills all the values as part of analyzing the code that
6539 -- initializes the dispatch tables.
6541 if Inside_Freezing_Actions
= 0
6542 and then (not Is_Library_Level_Entity
(Nam
)
6543 or else Suppress_Value_Tracking_On_Call
6544 (Nearest_Dynamic_Scope
(Current_Scope
)))
6545 and then (Comes_From_Source
(Nam
)
6546 or else (Present
(Alias
(Nam
))
6547 and then Comes_From_Source
(Alias
(Nam
))))
6549 Kill_Current_Values
;
6552 -- If we are warning about unread OUT parameters, this is the place to
6553 -- set Last_Assignment for OUT and IN OUT parameters. We have to do this
6554 -- after the above call to Kill_Current_Values (since that call clears
6555 -- the Last_Assignment field of all local variables).
6557 if (Warn_On_Modified_Unread
or Warn_On_All_Unread_Out_Parameters
)
6558 and then Comes_From_Source
(N
)
6559 and then In_Extended_Main_Source_Unit
(N
)
6566 F
:= First_Formal
(Nam
);
6567 A
:= First_Actual
(N
);
6568 while Present
(F
) and then Present
(A
) loop
6569 if Ekind_In
(F
, E_Out_Parameter
, E_In_Out_Parameter
)
6570 and then Warn_On_Modified_As_Out_Parameter
(F
)
6571 and then Is_Entity_Name
(A
)
6572 and then Present
(Entity
(A
))
6573 and then Comes_From_Source
(N
)
6574 and then Safe_To_Capture_Value
(N
, Entity
(A
))
6576 Set_Last_Assignment
(Entity
(A
), A
);
6585 -- If the subprogram is a primitive operation, check whether or not
6586 -- it is a correct dispatching call.
6588 if Is_Overloadable
(Nam
)
6589 and then Is_Dispatching_Operation
(Nam
)
6591 Check_Dispatching_Call
(N
);
6593 elsif Ekind
(Nam
) /= E_Subprogram_Type
6594 and then Is_Abstract_Subprogram
(Nam
)
6595 and then not In_Instance
6597 Error_Msg_NE
("cannot call abstract subprogram &!", N
, Nam
);
6600 -- If this is a dispatching call, generate the appropriate reference,
6601 -- for better source navigation in GPS.
6603 if Is_Overloadable
(Nam
)
6604 and then Present
(Controlling_Argument
(N
))
6606 Generate_Reference
(Nam
, Subp
, 'R');
6608 -- Normal case, not a dispatching call: generate a call reference
6611 Generate_Reference
(Nam
, Subp
, 's');
6614 if Is_Intrinsic_Subprogram
(Nam
) then
6615 Check_Intrinsic_Call
(N
);
6618 -- Check for violation of restriction No_Specific_Termination_Handlers
6619 -- and warn on a potentially blocking call to Abort_Task.
6621 if Restriction_Check_Required
(No_Specific_Termination_Handlers
)
6622 and then (Is_RTE
(Nam
, RE_Set_Specific_Handler
)
6624 Is_RTE
(Nam
, RE_Specific_Handler
))
6626 Check_Restriction
(No_Specific_Termination_Handlers
, N
);
6628 elsif Is_RTE
(Nam
, RE_Abort_Task
) then
6629 Check_Potentially_Blocking_Operation
(N
);
6632 -- A call to Ada.Real_Time.Timing_Events.Set_Handler to set a relative
6633 -- timing event violates restriction No_Relative_Delay (AI-0211). We
6634 -- need to check the second argument to determine whether it is an
6635 -- absolute or relative timing event.
6637 if Restriction_Check_Required
(No_Relative_Delay
)
6638 and then Is_RTE
(Nam
, RE_Set_Handler
)
6639 and then Is_RTE
(Etype
(Next_Actual
(First_Actual
(N
))), RE_Time_Span
)
6641 Check_Restriction
(No_Relative_Delay
, N
);
6644 -- Issue an error for a call to an eliminated subprogram. This routine
6645 -- will not perform the check if the call appears within a default
6648 Check_For_Eliminated_Subprogram
(Subp
, Nam
);
6650 -- In formal mode, the primitive operations of a tagged type or type
6651 -- extension do not include functions that return the tagged type.
6653 if Nkind
(N
) = N_Function_Call
6654 and then Is_Tagged_Type
(Etype
(N
))
6655 and then Is_Entity_Name
(Name
(N
))
6656 and then Is_Inherited_Operation_For_Type
(Entity
(Name
(N
)), Etype
(N
))
6658 Check_SPARK_05_Restriction
("function not inherited", N
);
6661 -- Implement rule in 12.5.1 (23.3/2): In an instance, if the actual is
6662 -- class-wide and the call dispatches on result in a context that does
6663 -- not provide a tag, the call raises Program_Error.
6665 if Nkind
(N
) = N_Function_Call
6666 and then In_Instance
6667 and then Is_Generic_Actual_Type
(Typ
)
6668 and then Is_Class_Wide_Type
(Typ
)
6669 and then Has_Controlling_Result
(Nam
)
6670 and then Nkind
(Parent
(N
)) = N_Object_Declaration
6672 -- Verify that none of the formals are controlling
6675 Call_OK
: Boolean := False;
6679 F
:= First_Formal
(Nam
);
6680 while Present
(F
) loop
6681 if Is_Controlling_Formal
(F
) then
6690 Error_Msg_Warn
:= SPARK_Mode
/= On
;
6691 Error_Msg_N
("!cannot determine tag of result<<", N
);
6692 Error_Msg_N
("\Program_Error [<<!", N
);
6694 Make_Raise_Program_Error
(Sloc
(N
),
6695 Reason
=> PE_Explicit_Raise
));
6700 -- Check for calling a function with OUT or IN OUT parameter when the
6701 -- calling context (us right now) is not Ada 2012, so does not allow
6702 -- OUT or IN OUT parameters in function calls. Functions declared in
6703 -- a predefined unit are OK, as they may be called indirectly from a
6704 -- user-declared instantiation.
6706 if Ada_Version
< Ada_2012
6707 and then Ekind
(Nam
) = E_Function
6708 and then Has_Out_Or_In_Out_Parameter
(Nam
)
6709 and then not In_Predefined_Unit
(Nam
)
6711 Error_Msg_NE
("& has at least one OUT or `IN OUT` parameter", N
, Nam
);
6712 Error_Msg_N
("\call to this function only allowed in Ada 2012", N
);
6715 -- Check the dimensions of the actuals in the call. For function calls,
6716 -- propagate the dimensions from the returned type to N.
6718 Analyze_Dimension_Call
(N
, Nam
);
6720 -- All done, evaluate call and deal with elaboration issues
6724 if Legacy_Elaboration_Checks
then
6725 Check_Elab_Call
(N
);
6728 -- Annotate the tree by creating a call marker in case the original call
6729 -- is transformed by expansion. The call marker is automatically saved
6730 -- for later examination by the ABE Processing phase.
6732 Build_Call_Marker
(N
);
6734 -- In GNATprove mode, expansion is disabled, but we want to inline some
6735 -- subprograms to facilitate formal verification. Indirect calls through
6736 -- a subprogram type or within a generic cannot be inlined. Inlining is
6737 -- performed only for calls subject to SPARK_Mode on.
6740 and then SPARK_Mode
= On
6741 and then Is_Overloadable
(Nam
)
6742 and then not Inside_A_Generic
6744 Nam_UA
:= Ultimate_Alias
(Nam
);
6745 Nam_Decl
:= Unit_Declaration_Node
(Nam_UA
);
6747 if Nkind
(Nam_Decl
) = N_Subprogram_Declaration
then
6748 Body_Id
:= Corresponding_Body
(Nam_Decl
);
6750 -- Nothing to do if the subprogram is not eligible for inlining in
6751 -- GNATprove mode, or inlining is disabled with switch -gnatdm
6753 if not Is_Inlined_Always
(Nam_UA
)
6754 or else not Can_Be_Inlined_In_GNATprove_Mode
(Nam_UA
, Body_Id
)
6755 or else Debug_Flag_M
6759 -- Calls cannot be inlined inside assertions, as GNATprove treats
6760 -- assertions as logic expressions. Only issue a message when the
6761 -- body has been seen, otherwise this leads to spurious messages
6762 -- on expression functions.
6764 elsif In_Assertion_Expr
/= 0 then
6765 if Present
(Body_Id
) then
6767 ("cannot inline & (in assertion expression)?", N
, Nam_UA
);
6770 -- Calls cannot be inlined inside default expressions
6772 elsif In_Default_Expr
then
6774 ("cannot inline & (in default expression)?", N
, Nam_UA
);
6776 -- Inlining should not be performed during pre-analysis
6778 elsif Full_Analysis
then
6780 -- Do not inline calls inside expression functions, as this
6781 -- would prevent interpreting them as logical formulas in
6782 -- GNATprove. Only issue a message when the body has been seen,
6783 -- otherwise this leads to spurious messages on callees that
6784 -- are themselves expression functions.
6786 if Present
(Current_Subprogram
)
6787 and then Is_Expression_Function_Or_Completion
6788 (Current_Subprogram
)
6790 if Present
(Body_Id
)
6791 and then Present
(Body_To_Inline
(Nam_Decl
))
6794 ("cannot inline & (inside expression function)?",
6798 -- With the one-pass inlining technique, a call cannot be
6799 -- inlined if the corresponding body has not been seen yet.
6801 elsif No
(Body_Id
) then
6803 ("cannot inline & (body not seen yet)?", N
, Nam_UA
);
6805 -- Nothing to do if there is no body to inline, indicating that
6806 -- the subprogram is not suitable for inlining in GNATprove
6809 elsif No
(Body_To_Inline
(Nam_Decl
)) then
6812 -- Calls cannot be inlined inside potentially unevaluated
6813 -- expressions, as this would create complex actions inside
6814 -- expressions, that are not handled by GNATprove.
6816 elsif Is_Potentially_Unevaluated
(N
) then
6818 ("cannot inline & (in potentially unevaluated context)?",
6821 -- Do not inline calls which would possibly lead to missing a
6822 -- type conversion check on an input parameter.
6824 elsif not Call_Can_Be_Inlined_In_GNATprove_Mode
(N
, Nam
) then
6826 ("cannot inline & (possible check on input parameters)?",
6829 -- Otherwise, inline the call
6832 Expand_Inlined_Call
(N
, Nam_UA
, Nam
);
6838 Mark_Use_Clauses
(Subp
);
6840 Warn_On_Overlapping_Actuals
(Nam
, N
);
6843 -----------------------------
6844 -- Resolve_Case_Expression --
6845 -----------------------------
6847 procedure Resolve_Case_Expression
(N
: Node_Id
; Typ
: Entity_Id
) is
6850 Alt_Typ
: Entity_Id
;
6854 Alt
:= First
(Alternatives
(N
));
6855 while Present
(Alt
) loop
6856 Alt_Expr
:= Expression
(Alt
);
6858 if Error_Posted
(Alt_Expr
) then
6862 Resolve
(Alt_Expr
, Typ
);
6863 Alt_Typ
:= Etype
(Alt_Expr
);
6865 -- When the expression is of a scalar subtype different from the
6866 -- result subtype, then insert a conversion to ensure the generation
6867 -- of a constraint check.
6869 if Is_Scalar_Type
(Alt_Typ
) and then Alt_Typ
/= Typ
then
6870 Rewrite
(Alt_Expr
, Convert_To
(Typ
, Alt_Expr
));
6871 Analyze_And_Resolve
(Alt_Expr
, Typ
);
6877 -- Apply RM 4.5.7 (17/3): whether the expression is statically or
6878 -- dynamically tagged must be known statically.
6880 if Is_Tagged_Type
(Typ
) and then not Is_Class_Wide_Type
(Typ
) then
6881 Alt
:= First
(Alternatives
(N
));
6882 Is_Dyn
:= Is_Dynamically_Tagged
(Expression
(Alt
));
6884 while Present
(Alt
) loop
6885 if Is_Dynamically_Tagged
(Expression
(Alt
)) /= Is_Dyn
then
6887 ("all or none of the dependent expressions can be "
6888 & "dynamically tagged", N
);
6896 Eval_Case_Expression
(N
);
6897 Analyze_Dimension
(N
);
6898 end Resolve_Case_Expression
;
6900 -------------------------------
6901 -- Resolve_Character_Literal --
6902 -------------------------------
6904 procedure Resolve_Character_Literal
(N
: Node_Id
; Typ
: Entity_Id
) is
6905 B_Typ
: constant Entity_Id
:= Base_Type
(Typ
);
6909 -- Verify that the character does belong to the type of the context
6911 Set_Etype
(N
, B_Typ
);
6912 Eval_Character_Literal
(N
);
6914 -- Wide_Wide_Character literals must always be defined, since the set
6915 -- of wide wide character literals is complete, i.e. if a character
6916 -- literal is accepted by the parser, then it is OK for wide wide
6917 -- character (out of range character literals are rejected).
6919 if Root_Type
(B_Typ
) = Standard_Wide_Wide_Character
then
6922 -- Always accept character literal for type Any_Character, which
6923 -- occurs in error situations and in comparisons of literals, both
6924 -- of which should accept all literals.
6926 elsif B_Typ
= Any_Character
then
6929 -- For Standard.Character or a type derived from it, check that the
6930 -- literal is in range.
6932 elsif Root_Type
(B_Typ
) = Standard_Character
then
6933 if In_Character_Range
(UI_To_CC
(Char_Literal_Value
(N
))) then
6937 -- For Standard.Wide_Character or a type derived from it, check that the
6938 -- literal is in range.
6940 elsif Root_Type
(B_Typ
) = Standard_Wide_Character
then
6941 if In_Wide_Character_Range
(UI_To_CC
(Char_Literal_Value
(N
))) then
6945 -- If the entity is already set, this has already been resolved in a
6946 -- generic context, or comes from expansion. Nothing else to do.
6948 elsif Present
(Entity
(N
)) then
6951 -- Otherwise we have a user defined character type, and we can use the
6952 -- standard visibility mechanisms to locate the referenced entity.
6955 C
:= Current_Entity
(N
);
6956 while Present
(C
) loop
6957 if Etype
(C
) = B_Typ
then
6958 Set_Entity_With_Checks
(N
, C
);
6959 Generate_Reference
(C
, N
);
6967 -- If we fall through, then the literal does not match any of the
6968 -- entries of the enumeration type. This isn't just a constraint error
6969 -- situation, it is an illegality (see RM 4.2).
6972 ("character not defined for }", N
, First_Subtype
(B_Typ
));
6973 end Resolve_Character_Literal
;
6975 ---------------------------
6976 -- Resolve_Comparison_Op --
6977 ---------------------------
6979 -- Context requires a boolean type, and plays no role in resolution.
6980 -- Processing identical to that for equality operators. The result type is
6981 -- the base type, which matters when pathological subtypes of booleans with
6982 -- limited ranges are used.
6984 procedure Resolve_Comparison_Op
(N
: Node_Id
; Typ
: Entity_Id
) is
6985 L
: constant Node_Id
:= Left_Opnd
(N
);
6986 R
: constant Node_Id
:= Right_Opnd
(N
);
6990 -- If this is an intrinsic operation which is not predefined, use the
6991 -- types of its declared arguments to resolve the possibly overloaded
6992 -- operands. Otherwise the operands are unambiguous and specify the
6995 if Scope
(Entity
(N
)) /= Standard_Standard
then
6996 T
:= Etype
(First_Entity
(Entity
(N
)));
6999 T
:= Find_Unique_Type
(L
, R
);
7001 if T
= Any_Fixed
then
7002 T
:= Unique_Fixed_Point_Type
(L
);
7006 Set_Etype
(N
, Base_Type
(Typ
));
7007 Generate_Reference
(T
, N
, ' ');
7009 -- Skip remaining processing if already set to Any_Type
7011 if T
= Any_Type
then
7015 -- Deal with other error cases
7017 if T
= Any_String
or else
7018 T
= Any_Composite
or else
7021 if T
= Any_Character
then
7022 Ambiguous_Character
(L
);
7024 Error_Msg_N
("ambiguous operands for comparison", N
);
7027 Set_Etype
(N
, Any_Type
);
7031 -- Resolve the operands if types OK
7035 Check_Unset_Reference
(L
);
7036 Check_Unset_Reference
(R
);
7037 Generate_Operator_Reference
(N
, T
);
7038 Check_Low_Bound_Tested
(N
);
7040 -- In SPARK, ordering operators <, <=, >, >= are not defined for Boolean
7041 -- types or array types except String.
7043 if Is_Boolean_Type
(T
) then
7044 Check_SPARK_05_Restriction
7045 ("comparison is not defined on Boolean type", N
);
7047 elsif Is_Array_Type
(T
)
7048 and then Base_Type
(T
) /= Standard_String
7050 Check_SPARK_05_Restriction
7051 ("comparison is not defined on array types other than String", N
);
7054 -- Check comparison on unordered enumeration
7056 if Bad_Unordered_Enumeration_Reference
(N
, Etype
(L
)) then
7057 Error_Msg_Sloc
:= Sloc
(Etype
(L
));
7059 ("comparison on unordered enumeration type& declared#?U?",
7063 Analyze_Dimension
(N
);
7065 -- Evaluate the relation (note we do this after the above check since
7066 -- this Eval call may change N to True/False. Skip this evaluation
7067 -- inside assertions, in order to keep assertions as written by users
7068 -- for tools that rely on these, e.g. GNATprove for loop invariants.
7069 -- Except evaluation is still performed even inside assertions for
7070 -- comparisons between values of universal type, which are useless
7071 -- for static analysis tools, and not supported even by GNATprove.
7073 if In_Assertion_Expr
= 0
7074 or else (Is_Universal_Numeric_Type
(Etype
(L
))
7076 Is_Universal_Numeric_Type
(Etype
(R
)))
7078 Eval_Relational_Op
(N
);
7080 end Resolve_Comparison_Op
;
7082 -----------------------------------------
7083 -- Resolve_Discrete_Subtype_Indication --
7084 -----------------------------------------
7086 procedure Resolve_Discrete_Subtype_Indication
7094 Analyze
(Subtype_Mark
(N
));
7095 S
:= Entity
(Subtype_Mark
(N
));
7097 if Nkind
(Constraint
(N
)) /= N_Range_Constraint
then
7098 Error_Msg_N
("expect range constraint for discrete type", N
);
7099 Set_Etype
(N
, Any_Type
);
7102 R
:= Range_Expression
(Constraint
(N
));
7110 if Base_Type
(S
) /= Base_Type
(Typ
) then
7112 ("expect subtype of }", N
, First_Subtype
(Typ
));
7114 -- Rewrite the constraint as a range of Typ
7115 -- to allow compilation to proceed further.
7118 Rewrite
(Low_Bound
(R
),
7119 Make_Attribute_Reference
(Sloc
(Low_Bound
(R
)),
7120 Prefix
=> New_Occurrence_Of
(Typ
, Sloc
(R
)),
7121 Attribute_Name
=> Name_First
));
7122 Rewrite
(High_Bound
(R
),
7123 Make_Attribute_Reference
(Sloc
(High_Bound
(R
)),
7124 Prefix
=> New_Occurrence_Of
(Typ
, Sloc
(R
)),
7125 Attribute_Name
=> Name_First
));
7129 Set_Etype
(N
, Etype
(R
));
7131 -- Additionally, we must check that the bounds are compatible
7132 -- with the given subtype, which might be different from the
7133 -- type of the context.
7135 Apply_Range_Check
(R
, S
);
7137 -- ??? If the above check statically detects a Constraint_Error
7138 -- it replaces the offending bound(s) of the range R with a
7139 -- Constraint_Error node. When the itype which uses these bounds
7140 -- is frozen the resulting call to Duplicate_Subexpr generates
7141 -- a new temporary for the bounds.
7143 -- Unfortunately there are other itypes that are also made depend
7144 -- on these bounds, so when Duplicate_Subexpr is called they get
7145 -- a forward reference to the newly created temporaries and Gigi
7146 -- aborts on such forward references. This is probably sign of a
7147 -- more fundamental problem somewhere else in either the order of
7148 -- itype freezing or the way certain itypes are constructed.
7150 -- To get around this problem we call Remove_Side_Effects right
7151 -- away if either bounds of R are a Constraint_Error.
7154 L
: constant Node_Id
:= Low_Bound
(R
);
7155 H
: constant Node_Id
:= High_Bound
(R
);
7158 if Nkind
(L
) = N_Raise_Constraint_Error
then
7159 Remove_Side_Effects
(L
);
7162 if Nkind
(H
) = N_Raise_Constraint_Error
then
7163 Remove_Side_Effects
(H
);
7167 Check_Unset_Reference
(Low_Bound
(R
));
7168 Check_Unset_Reference
(High_Bound
(R
));
7171 end Resolve_Discrete_Subtype_Indication
;
7173 -------------------------
7174 -- Resolve_Entity_Name --
7175 -------------------------
7177 -- Used to resolve identifiers and expanded names
7179 procedure Resolve_Entity_Name
(N
: Node_Id
; Typ
: Entity_Id
) is
7180 function Is_Assignment_Or_Object_Expression
7182 Expr
: Node_Id
) return Boolean;
7183 -- Determine whether node Context denotes an assignment statement or an
7184 -- object declaration whose expression is node Expr.
7186 ----------------------------------------
7187 -- Is_Assignment_Or_Object_Expression --
7188 ----------------------------------------
7190 function Is_Assignment_Or_Object_Expression
7192 Expr
: Node_Id
) return Boolean
7195 if Nkind_In
(Context
, N_Assignment_Statement
,
7196 N_Object_Declaration
)
7197 and then Expression
(Context
) = Expr
7201 -- Check whether a construct that yields a name is the expression of
7202 -- an assignment statement or an object declaration.
7204 elsif (Nkind_In
(Context
, N_Attribute_Reference
,
7205 N_Explicit_Dereference
,
7206 N_Indexed_Component
,
7207 N_Selected_Component
,
7209 and then Prefix
(Context
) = Expr
)
7211 (Nkind_In
(Context
, N_Type_Conversion
,
7212 N_Unchecked_Type_Conversion
)
7213 and then Expression
(Context
) = Expr
)
7216 Is_Assignment_Or_Object_Expression
7217 (Context
=> Parent
(Context
),
7220 -- Otherwise the context is not an assignment statement or an object
7226 end Is_Assignment_Or_Object_Expression
;
7230 E
: constant Entity_Id
:= Entity
(N
);
7233 -- Start of processing for Resolve_Entity_Name
7236 -- If garbage from errors, set to Any_Type and return
7238 if No
(E
) and then Total_Errors_Detected
/= 0 then
7239 Set_Etype
(N
, Any_Type
);
7243 -- Replace named numbers by corresponding literals. Note that this is
7244 -- the one case where Resolve_Entity_Name must reset the Etype, since
7245 -- it is currently marked as universal.
7247 if Ekind
(E
) = E_Named_Integer
then
7249 Eval_Named_Integer
(N
);
7251 elsif Ekind
(E
) = E_Named_Real
then
7253 Eval_Named_Real
(N
);
7255 -- For enumeration literals, we need to make sure that a proper style
7256 -- check is done, since such literals are overloaded, and thus we did
7257 -- not do a style check during the first phase of analysis.
7259 elsif Ekind
(E
) = E_Enumeration_Literal
then
7260 Set_Entity_With_Checks
(N
, E
);
7261 Eval_Entity_Name
(N
);
7263 -- Case of (sub)type name appearing in a context where an expression
7264 -- is expected. This is legal if occurrence is a current instance.
7265 -- See RM 8.6 (17/3).
7267 elsif Is_Type
(E
) then
7268 if Is_Current_Instance
(N
) then
7271 -- Any other use is an error
7275 ("invalid use of subtype mark in expression or call", N
);
7278 -- Check discriminant use if entity is discriminant in current scope,
7279 -- i.e. discriminant of record or concurrent type currently being
7280 -- analyzed. Uses in corresponding body are unrestricted.
7282 elsif Ekind
(E
) = E_Discriminant
7283 and then Scope
(E
) = Current_Scope
7284 and then not Has_Completion
(Current_Scope
)
7286 Check_Discriminant_Use
(N
);
7288 -- A parameterless generic function cannot appear in a context that
7289 -- requires resolution.
7291 elsif Ekind
(E
) = E_Generic_Function
then
7292 Error_Msg_N
("illegal use of generic function", N
);
7294 -- In Ada 83 an OUT parameter cannot be read, but attributes of
7295 -- array types (i.e. bounds and length) are legal.
7297 elsif Ekind
(E
) = E_Out_Parameter
7298 and then (Nkind
(Parent
(N
)) /= N_Attribute_Reference
7299 or else Is_Scalar_Type
(Etype
(E
)))
7301 and then (Nkind
(Parent
(N
)) in N_Op
7302 or else Nkind
(Parent
(N
)) = N_Explicit_Dereference
7303 or else Is_Assignment_Or_Object_Expression
7304 (Context
=> Parent
(N
),
7307 if Ada_Version
= Ada_83
then
7308 Error_Msg_N
("(Ada 83) illegal reading of out parameter", N
);
7311 -- In all other cases, just do the possible static evaluation
7314 -- A deferred constant that appears in an expression must have a
7315 -- completion, unless it has been removed by in-place expansion of
7316 -- an aggregate. A constant that is a renaming does not need
7319 if Ekind
(E
) = E_Constant
7320 and then Comes_From_Source
(E
)
7321 and then No
(Constant_Value
(E
))
7322 and then Is_Frozen
(Etype
(E
))
7323 and then not In_Spec_Expression
7324 and then not Is_Imported
(E
)
7325 and then Nkind
(Parent
(E
)) /= N_Object_Renaming_Declaration
7327 if No_Initialization
(Parent
(E
))
7328 or else (Present
(Full_View
(E
))
7329 and then No_Initialization
(Parent
(Full_View
(E
))))
7334 ("deferred constant is frozen before completion", N
);
7338 Eval_Entity_Name
(N
);
7343 -- When the entity appears in a parameter association, retrieve the
7344 -- related subprogram call.
7346 if Nkind
(Par
) = N_Parameter_Association
then
7347 Par
:= Parent
(Par
);
7350 if Comes_From_Source
(N
) then
7352 -- The following checks are only relevant when SPARK_Mode is on as
7353 -- they are not standard Ada legality rules.
7355 if SPARK_Mode
= On
then
7357 -- An effectively volatile object subject to enabled properties
7358 -- Async_Writers or Effective_Reads must appear in non-interfering
7359 -- context (SPARK RM 7.1.3(12)).
7362 and then Is_Effectively_Volatile
(E
)
7363 and then (Async_Writers_Enabled
(E
)
7364 or else Effective_Reads_Enabled
(E
))
7365 and then not Is_OK_Volatile_Context
(Par
, N
)
7368 ("volatile object cannot appear in this context "
7369 & "(SPARK RM 7.1.3(12))", N
);
7372 -- Check for possible elaboration issues with respect to reads of
7373 -- variables. The act of renaming the variable is not considered a
7374 -- read as it simply establishes an alias.
7376 if Legacy_Elaboration_Checks
7377 and then Ekind
(E
) = E_Variable
7378 and then Dynamic_Elaboration_Checks
7379 and then Nkind
(Par
) /= N_Object_Renaming_Declaration
7381 Check_Elab_Call
(N
);
7384 -- The variable may eventually become a constituent of a single
7385 -- protected/task type. Record the reference now and verify its
7386 -- legality when analyzing the contract of the variable
7389 if Ekind
(E
) = E_Variable
then
7390 Record_Possible_Part_Of_Reference
(E
, N
);
7394 -- A Ghost entity must appear in a specific context
7396 if Is_Ghost_Entity
(E
) then
7397 Check_Ghost_Context
(E
, N
);
7401 Mark_Use_Clauses
(E
);
7402 end Resolve_Entity_Name
;
7408 procedure Resolve_Entry
(Entry_Name
: Node_Id
) is
7409 Loc
: constant Source_Ptr
:= Sloc
(Entry_Name
);
7417 function Actual_Index_Type
(E
: Entity_Id
) return Entity_Id
;
7418 -- If the bounds of the entry family being called depend on task
7419 -- discriminants, build a new index subtype where a discriminant is
7420 -- replaced with the value of the discriminant of the target task.
7421 -- The target task is the prefix of the entry name in the call.
7423 -----------------------
7424 -- Actual_Index_Type --
7425 -----------------------
7427 function Actual_Index_Type
(E
: Entity_Id
) return Entity_Id
is
7428 Typ
: constant Entity_Id
:= Entry_Index_Type
(E
);
7429 Tsk
: constant Entity_Id
:= Scope
(E
);
7430 Lo
: constant Node_Id
:= Type_Low_Bound
(Typ
);
7431 Hi
: constant Node_Id
:= Type_High_Bound
(Typ
);
7434 function Actual_Discriminant_Ref
(Bound
: Node_Id
) return Node_Id
;
7435 -- If the bound is given by a discriminant, replace with a reference
7436 -- to the discriminant of the same name in the target task. If the
7437 -- entry name is the target of a requeue statement and the entry is
7438 -- in the current protected object, the bound to be used is the
7439 -- discriminal of the object (see Apply_Range_Checks for details of
7440 -- the transformation).
7442 -----------------------------
7443 -- Actual_Discriminant_Ref --
7444 -----------------------------
7446 function Actual_Discriminant_Ref
(Bound
: Node_Id
) return Node_Id
is
7447 Typ
: constant Entity_Id
:= Etype
(Bound
);
7451 Remove_Side_Effects
(Bound
);
7453 if not Is_Entity_Name
(Bound
)
7454 or else Ekind
(Entity
(Bound
)) /= E_Discriminant
7458 elsif Is_Protected_Type
(Tsk
)
7459 and then In_Open_Scopes
(Tsk
)
7460 and then Nkind
(Parent
(Entry_Name
)) = N_Requeue_Statement
7462 -- Note: here Bound denotes a discriminant of the corresponding
7463 -- record type tskV, whose discriminal is a formal of the
7464 -- init-proc tskVIP. What we want is the body discriminal,
7465 -- which is associated to the discriminant of the original
7466 -- concurrent type tsk.
7468 return New_Occurrence_Of
7469 (Find_Body_Discriminal
(Entity
(Bound
)), Loc
);
7473 Make_Selected_Component
(Loc
,
7474 Prefix
=> New_Copy_Tree
(Prefix
(Prefix
(Entry_Name
))),
7475 Selector_Name
=> New_Occurrence_Of
(Entity
(Bound
), Loc
));
7480 end Actual_Discriminant_Ref
;
7482 -- Start of processing for Actual_Index_Type
7485 if not Has_Discriminants
(Tsk
)
7486 or else (not Is_Entity_Name
(Lo
) and then not Is_Entity_Name
(Hi
))
7488 return Entry_Index_Type
(E
);
7491 New_T
:= Create_Itype
(Ekind
(Typ
), Parent
(Entry_Name
));
7492 Set_Etype
(New_T
, Base_Type
(Typ
));
7493 Set_Size_Info
(New_T
, Typ
);
7494 Set_RM_Size
(New_T
, RM_Size
(Typ
));
7495 Set_Scalar_Range
(New_T
,
7496 Make_Range
(Sloc
(Entry_Name
),
7497 Low_Bound
=> Actual_Discriminant_Ref
(Lo
),
7498 High_Bound
=> Actual_Discriminant_Ref
(Hi
)));
7502 end Actual_Index_Type
;
7504 -- Start of processing for Resolve_Entry
7507 -- Find name of entry being called, and resolve prefix of name with its
7508 -- own type. The prefix can be overloaded, and the name and signature of
7509 -- the entry must be taken into account.
7511 if Nkind
(Entry_Name
) = N_Indexed_Component
then
7513 -- Case of dealing with entry family within the current tasks
7515 E_Name
:= Prefix
(Entry_Name
);
7518 E_Name
:= Entry_Name
;
7521 if Is_Entity_Name
(E_Name
) then
7523 -- Entry call to an entry (or entry family) in the current task. This
7524 -- is legal even though the task will deadlock. Rewrite as call to
7527 -- This can also be a call to an entry in an enclosing task. If this
7528 -- is a single task, we have to retrieve its name, because the scope
7529 -- of the entry is the task type, not the object. If the enclosing
7530 -- task is a task type, the identity of the task is given by its own
7533 -- Finally this can be a requeue on an entry of the same task or
7534 -- protected object.
7536 S
:= Scope
(Entity
(E_Name
));
7538 for J
in reverse 0 .. Scope_Stack
.Last
loop
7539 if Is_Task_Type
(Scope_Stack
.Table
(J
).Entity
)
7540 and then not Comes_From_Source
(S
)
7542 -- S is an enclosing task or protected object. The concurrent
7543 -- declaration has been converted into a type declaration, and
7544 -- the object itself has an object declaration that follows
7545 -- the type in the same declarative part.
7547 Tsk
:= Next_Entity
(S
);
7548 while Etype
(Tsk
) /= S
loop
7555 elsif S
= Scope_Stack
.Table
(J
).Entity
then
7557 -- Call to current task. Will be transformed into call to Self
7565 Make_Selected_Component
(Loc
,
7566 Prefix
=> New_Occurrence_Of
(S
, Loc
),
7568 New_Occurrence_Of
(Entity
(E_Name
), Loc
));
7569 Rewrite
(E_Name
, New_N
);
7572 elsif Nkind
(Entry_Name
) = N_Selected_Component
7573 and then Is_Overloaded
(Prefix
(Entry_Name
))
7575 -- Use the entry name (which must be unique at this point) to find
7576 -- the prefix that returns the corresponding task/protected type.
7579 Pref
: constant Node_Id
:= Prefix
(Entry_Name
);
7580 Ent
: constant Entity_Id
:= Entity
(Selector_Name
(Entry_Name
));
7585 Get_First_Interp
(Pref
, I
, It
);
7586 while Present
(It
.Typ
) loop
7587 if Scope
(Ent
) = It
.Typ
then
7588 Set_Etype
(Pref
, It
.Typ
);
7592 Get_Next_Interp
(I
, It
);
7597 if Nkind
(Entry_Name
) = N_Selected_Component
then
7598 Resolve
(Prefix
(Entry_Name
));
7600 else pragma Assert
(Nkind
(Entry_Name
) = N_Indexed_Component
);
7601 Nam
:= Entity
(Selector_Name
(Prefix
(Entry_Name
)));
7602 Resolve
(Prefix
(Prefix
(Entry_Name
)));
7603 Index
:= First
(Expressions
(Entry_Name
));
7604 Resolve
(Index
, Entry_Index_Type
(Nam
));
7606 -- Generate a reference for the index when it denotes an entity
7608 if Is_Entity_Name
(Index
) then
7609 Generate_Reference
(Entity
(Index
), Nam
);
7612 -- Up to this point the expression could have been the actual in a
7613 -- simple entry call, and be given by a named association.
7615 if Nkind
(Index
) = N_Parameter_Association
then
7616 Error_Msg_N
("expect expression for entry index", Index
);
7618 Apply_Range_Check
(Index
, Actual_Index_Type
(Nam
));
7623 ------------------------
7624 -- Resolve_Entry_Call --
7625 ------------------------
7627 procedure Resolve_Entry_Call
(N
: Node_Id
; Typ
: Entity_Id
) is
7628 Entry_Name
: constant Node_Id
:= Name
(N
);
7629 Loc
: constant Source_Ptr
:= Sloc
(Entry_Name
);
7637 -- We kill all checks here, because it does not seem worth the effort to
7638 -- do anything better, an entry call is a big operation.
7642 -- Processing of the name is similar for entry calls and protected
7643 -- operation calls. Once the entity is determined, we can complete
7644 -- the resolution of the actuals.
7646 -- The selector may be overloaded, in the case of a protected object
7647 -- with overloaded functions. The type of the context is used for
7650 if Nkind
(Entry_Name
) = N_Selected_Component
7651 and then Is_Overloaded
(Selector_Name
(Entry_Name
))
7652 and then Typ
/= Standard_Void_Type
7659 Get_First_Interp
(Selector_Name
(Entry_Name
), I
, It
);
7660 while Present
(It
.Typ
) loop
7661 if Covers
(Typ
, It
.Typ
) then
7662 Set_Entity
(Selector_Name
(Entry_Name
), It
.Nam
);
7663 Set_Etype
(Entry_Name
, It
.Typ
);
7665 Generate_Reference
(It
.Typ
, N
, ' ');
7668 Get_Next_Interp
(I
, It
);
7673 Resolve_Entry
(Entry_Name
);
7675 if Nkind
(Entry_Name
) = N_Selected_Component
then
7677 -- Simple entry or protected operation call
7679 Nam
:= Entity
(Selector_Name
(Entry_Name
));
7680 Obj
:= Prefix
(Entry_Name
);
7682 if Is_Subprogram
(Nam
) then
7683 Check_For_Eliminated_Subprogram
(Entry_Name
, Nam
);
7686 Was_Over
:= Is_Overloaded
(Selector_Name
(Entry_Name
));
7688 else pragma Assert
(Nkind
(Entry_Name
) = N_Indexed_Component
);
7690 -- Call to member of entry family
7692 Nam
:= Entity
(Selector_Name
(Prefix
(Entry_Name
)));
7693 Obj
:= Prefix
(Prefix
(Entry_Name
));
7694 Was_Over
:= Is_Overloaded
(Selector_Name
(Prefix
(Entry_Name
)));
7697 -- We cannot in general check the maximum depth of protected entry calls
7698 -- at compile time. But we can tell that any protected entry call at all
7699 -- violates a specified nesting depth of zero.
7701 if Is_Protected_Type
(Scope
(Nam
)) then
7702 Check_Restriction
(Max_Entry_Queue_Length
, N
);
7705 -- Use context type to disambiguate a protected function that can be
7706 -- called without actuals and that returns an array type, and where the
7707 -- argument list may be an indexing of the returned value.
7709 if Ekind
(Nam
) = E_Function
7710 and then Needs_No_Actuals
(Nam
)
7711 and then Present
(Parameter_Associations
(N
))
7713 ((Is_Array_Type
(Etype
(Nam
))
7714 and then Covers
(Typ
, Component_Type
(Etype
(Nam
))))
7716 or else (Is_Access_Type
(Etype
(Nam
))
7717 and then Is_Array_Type
(Designated_Type
(Etype
(Nam
)))
7721 Component_Type
(Designated_Type
(Etype
(Nam
))))))
7724 Index_Node
: Node_Id
;
7728 Make_Indexed_Component
(Loc
,
7730 Make_Function_Call
(Loc
, Name
=> Relocate_Node
(Entry_Name
)),
7731 Expressions
=> Parameter_Associations
(N
));
7733 -- Since we are correcting a node classification error made by the
7734 -- parser, we call Replace rather than Rewrite.
7736 Replace
(N
, Index_Node
);
7737 Set_Etype
(Prefix
(N
), Etype
(Nam
));
7739 Resolve_Indexed_Component
(N
, Typ
);
7744 if Ekind_In
(Nam
, E_Entry
, E_Entry_Family
)
7745 and then Present
(Contract_Wrapper
(Nam
))
7746 and then Current_Scope
/= Contract_Wrapper
(Nam
)
7748 -- Note the entity being called before rewriting the call, so that
7749 -- it appears used at this point.
7751 Generate_Reference
(Nam
, Entry_Name
, 'r');
7753 -- Rewrite as call to the precondition wrapper, adding the task
7754 -- object to the list of actuals. If the call is to a member of an
7755 -- entry family, include the index as well.
7759 New_Actuals
: List_Id
;
7762 New_Actuals
:= New_List
(Obj
);
7764 if Nkind
(Entry_Name
) = N_Indexed_Component
then
7765 Append_To
(New_Actuals
,
7766 New_Copy_Tree
(First
(Expressions
(Entry_Name
))));
7769 Append_List
(Parameter_Associations
(N
), New_Actuals
);
7771 Make_Procedure_Call_Statement
(Loc
,
7773 New_Occurrence_Of
(Contract_Wrapper
(Nam
), Loc
),
7774 Parameter_Associations
=> New_Actuals
);
7775 Rewrite
(N
, New_Call
);
7777 -- Preanalyze and resolve new call. Current procedure is called
7778 -- from Resolve_Call, after which expansion will take place.
7780 Preanalyze_And_Resolve
(N
);
7785 -- The operation name may have been overloaded. Order the actuals
7786 -- according to the formals of the resolved entity, and set the return
7787 -- type to that of the operation.
7790 Normalize_Actuals
(N
, Nam
, False, Norm_OK
);
7791 pragma Assert
(Norm_OK
);
7792 Set_Etype
(N
, Etype
(Nam
));
7794 -- Reset the Is_Overloaded flag, since resolution is now completed
7796 -- Simple entry call
7798 if Nkind
(Entry_Name
) = N_Selected_Component
then
7799 Set_Is_Overloaded
(Selector_Name
(Entry_Name
), False);
7801 -- Call to a member of an entry family
7803 else pragma Assert
(Nkind
(Entry_Name
) = N_Indexed_Component
);
7804 Set_Is_Overloaded
(Selector_Name
(Prefix
(Entry_Name
)), False);
7808 Resolve_Actuals
(N
, Nam
);
7809 Check_Internal_Protected_Use
(N
, Nam
);
7811 -- Create a call reference to the entry
7813 Generate_Reference
(Nam
, Entry_Name
, 's');
7815 if Ekind_In
(Nam
, E_Entry
, E_Entry_Family
) then
7816 Check_Potentially_Blocking_Operation
(N
);
7819 -- Verify that a procedure call cannot masquerade as an entry
7820 -- call where an entry call is expected.
7822 if Ekind
(Nam
) = E_Procedure
then
7823 if Nkind
(Parent
(N
)) = N_Entry_Call_Alternative
7824 and then N
= Entry_Call_Statement
(Parent
(N
))
7826 Error_Msg_N
("entry call required in select statement", N
);
7828 elsif Nkind
(Parent
(N
)) = N_Triggering_Alternative
7829 and then N
= Triggering_Statement
(Parent
(N
))
7831 Error_Msg_N
("triggering statement cannot be procedure call", N
);
7833 elsif Ekind
(Scope
(Nam
)) = E_Task_Type
7834 and then not In_Open_Scopes
(Scope
(Nam
))
7836 Error_Msg_N
("task has no entry with this name", Entry_Name
);
7840 -- After resolution, entry calls and protected procedure calls are
7841 -- changed into entry calls, for expansion. The structure of the node
7842 -- does not change, so it can safely be done in place. Protected
7843 -- function calls must keep their structure because they are
7846 if Ekind
(Nam
) /= E_Function
then
7848 -- A protected operation that is not a function may modify the
7849 -- corresponding object, and cannot apply to a constant. If this
7850 -- is an internal call, the prefix is the type itself.
7852 if Is_Protected_Type
(Scope
(Nam
))
7853 and then not Is_Variable
(Obj
)
7854 and then (not Is_Entity_Name
(Obj
)
7855 or else not Is_Type
(Entity
(Obj
)))
7858 ("prefix of protected procedure or entry call must be variable",
7863 Entry_Call
: Node_Id
;
7867 Make_Entry_Call_Statement
(Loc
,
7869 Parameter_Associations
=> Parameter_Associations
(N
));
7871 -- Inherit relevant attributes from the original call
7873 Set_First_Named_Actual
7874 (Entry_Call
, First_Named_Actual
(N
));
7876 Set_Is_Elaboration_Checks_OK_Node
7877 (Entry_Call
, Is_Elaboration_Checks_OK_Node
(N
));
7879 Set_Is_Elaboration_Warnings_OK_Node
7880 (Entry_Call
, Is_Elaboration_Warnings_OK_Node
(N
));
7882 Set_Is_SPARK_Mode_On_Node
7883 (Entry_Call
, Is_SPARK_Mode_On_Node
(N
));
7885 Rewrite
(N
, Entry_Call
);
7886 Set_Analyzed
(N
, True);
7889 -- Protected functions can return on the secondary stack, in which
7890 -- case we must trigger the transient scope mechanism.
7892 elsif Expander_Active
7893 and then Requires_Transient_Scope
(Etype
(Nam
))
7895 Establish_Transient_Scope
(N
, Sec_Stack
=> True);
7897 end Resolve_Entry_Call
;
7899 -------------------------
7900 -- Resolve_Equality_Op --
7901 -------------------------
7903 -- Both arguments must have the same type, and the boolean context does
7904 -- not participate in the resolution. The first pass verifies that the
7905 -- interpretation is not ambiguous, and the type of the left argument is
7906 -- correctly set, or is Any_Type in case of ambiguity. If both arguments
7907 -- are strings or aggregates, allocators, or Null, they are ambiguous even
7908 -- though they carry a single (universal) type. Diagnose this case here.
7910 procedure Resolve_Equality_Op
(N
: Node_Id
; Typ
: Entity_Id
) is
7911 L
: constant Node_Id
:= Left_Opnd
(N
);
7912 R
: constant Node_Id
:= Right_Opnd
(N
);
7913 T
: Entity_Id
:= Find_Unique_Type
(L
, R
);
7915 procedure Check_If_Expression
(Cond
: Node_Id
);
7916 -- The resolution rule for if expressions requires that each such must
7917 -- have a unique type. This means that if several dependent expressions
7918 -- are of a non-null anonymous access type, and the context does not
7919 -- impose an expected type (as can be the case in an equality operation)
7920 -- the expression must be rejected.
7922 procedure Explain_Redundancy
(N
: Node_Id
);
7923 -- Attempt to explain the nature of a redundant comparison with True. If
7924 -- the expression N is too complex, this routine issues a general error
7927 function Find_Unique_Access_Type
return Entity_Id
;
7928 -- In the case of allocators and access attributes, the context must
7929 -- provide an indication of the specific access type to be used. If
7930 -- one operand is of such a "generic" access type, check whether there
7931 -- is a specific visible access type that has the same designated type.
7932 -- This is semantically dubious, and of no interest to any real code,
7933 -- but c48008a makes it all worthwhile.
7935 -------------------------
7936 -- Check_If_Expression --
7937 -------------------------
7939 procedure Check_If_Expression
(Cond
: Node_Id
) is
7940 Then_Expr
: Node_Id
;
7941 Else_Expr
: Node_Id
;
7944 if Nkind
(Cond
) = N_If_Expression
then
7945 Then_Expr
:= Next
(First
(Expressions
(Cond
)));
7946 Else_Expr
:= Next
(Then_Expr
);
7948 if Nkind
(Then_Expr
) /= N_Null
7949 and then Nkind
(Else_Expr
) /= N_Null
7951 Error_Msg_N
("cannot determine type of if expression", Cond
);
7954 end Check_If_Expression
;
7956 ------------------------
7957 -- Explain_Redundancy --
7958 ------------------------
7960 procedure Explain_Redundancy
(N
: Node_Id
) is
7968 -- Strip the operand down to an entity
7971 if Nkind
(Val
) = N_Selected_Component
then
7972 Val
:= Selector_Name
(Val
);
7978 -- The construct denotes an entity
7980 if Is_Entity_Name
(Val
) and then Present
(Entity
(Val
)) then
7981 Val_Id
:= Entity
(Val
);
7983 -- Do not generate an error message when the comparison is done
7984 -- against the enumeration literal Standard.True.
7986 if Ekind
(Val_Id
) /= E_Enumeration_Literal
then
7988 -- Build a customized error message
7991 Add_Str_To_Name_Buffer
("?r?");
7993 if Ekind
(Val_Id
) = E_Component
then
7994 Add_Str_To_Name_Buffer
("component ");
7996 elsif Ekind
(Val_Id
) = E_Constant
then
7997 Add_Str_To_Name_Buffer
("constant ");
7999 elsif Ekind
(Val_Id
) = E_Discriminant
then
8000 Add_Str_To_Name_Buffer
("discriminant ");
8002 elsif Is_Formal
(Val_Id
) then
8003 Add_Str_To_Name_Buffer
("parameter ");
8005 elsif Ekind
(Val_Id
) = E_Variable
then
8006 Add_Str_To_Name_Buffer
("variable ");
8009 Add_Str_To_Name_Buffer
("& is always True!");
8012 Error_Msg_NE
(Get_Name_String
(Error
), Val
, Val_Id
);
8015 -- The construct is too complex to disect, issue a general message
8018 Error_Msg_N
("?r?expression is always True!", Val
);
8020 end Explain_Redundancy
;
8022 -----------------------------
8023 -- Find_Unique_Access_Type --
8024 -----------------------------
8026 function Find_Unique_Access_Type
return Entity_Id
is
8032 if Ekind_In
(Etype
(R
), E_Allocator_Type
,
8033 E_Access_Attribute_Type
)
8035 Acc
:= Designated_Type
(Etype
(R
));
8037 elsif Ekind_In
(Etype
(L
), E_Allocator_Type
,
8038 E_Access_Attribute_Type
)
8040 Acc
:= Designated_Type
(Etype
(L
));
8046 while S
/= Standard_Standard
loop
8047 E
:= First_Entity
(S
);
8048 while Present
(E
) loop
8050 and then Is_Access_Type
(E
)
8051 and then Ekind
(E
) /= E_Allocator_Type
8052 and then Designated_Type
(E
) = Base_Type
(Acc
)
8064 end Find_Unique_Access_Type
;
8066 -- Start of processing for Resolve_Equality_Op
8069 Set_Etype
(N
, Base_Type
(Typ
));
8070 Generate_Reference
(T
, N
, ' ');
8072 if T
= Any_Fixed
then
8073 T
:= Unique_Fixed_Point_Type
(L
);
8076 if T
/= Any_Type
then
8077 if T
= Any_String
or else
8078 T
= Any_Composite
or else
8081 if T
= Any_Character
then
8082 Ambiguous_Character
(L
);
8084 Error_Msg_N
("ambiguous operands for equality", N
);
8087 Set_Etype
(N
, Any_Type
);
8090 elsif T
= Any_Access
8091 or else Ekind_In
(T
, E_Allocator_Type
, E_Access_Attribute_Type
)
8093 T
:= Find_Unique_Access_Type
;
8096 Error_Msg_N
("ambiguous operands for equality", N
);
8097 Set_Etype
(N
, Any_Type
);
8101 -- If expressions must have a single type, and if the context does
8102 -- not impose one the dependent expressions cannot be anonymous
8105 -- Why no similar processing for case expressions???
8107 elsif Ada_Version
>= Ada_2012
8108 and then Ekind_In
(Etype
(L
), E_Anonymous_Access_Type
,
8109 E_Anonymous_Access_Subprogram_Type
)
8110 and then Ekind_In
(Etype
(R
), E_Anonymous_Access_Type
,
8111 E_Anonymous_Access_Subprogram_Type
)
8113 Check_If_Expression
(L
);
8114 Check_If_Expression
(R
);
8120 -- In SPARK, equality operators = and /= for array types other than
8121 -- String are only defined when, for each index position, the
8122 -- operands have equal static bounds.
8124 if Is_Array_Type
(T
) then
8126 -- Protect call to Matching_Static_Array_Bounds to avoid costly
8127 -- operation if not needed.
8129 if Restriction_Check_Required
(SPARK_05
)
8130 and then Base_Type
(T
) /= Standard_String
8131 and then Base_Type
(Etype
(L
)) = Base_Type
(Etype
(R
))
8132 and then Etype
(L
) /= Any_Composite
-- or else L in error
8133 and then Etype
(R
) /= Any_Composite
-- or else R in error
8134 and then not Matching_Static_Array_Bounds
(Etype
(L
), Etype
(R
))
8136 Check_SPARK_05_Restriction
8137 ("array types should have matching static bounds", N
);
8141 -- If the unique type is a class-wide type then it will be expanded
8142 -- into a dispatching call to the predefined primitive. Therefore we
8143 -- check here for potential violation of such restriction.
8145 if Is_Class_Wide_Type
(T
) then
8146 Check_Restriction
(No_Dispatching_Calls
, N
);
8149 -- Only warn for redundant equality comparison to True for objects
8150 -- (e.g. "X = True") and operations (e.g. "(X < Y) = True"). For
8151 -- other expressions, it may be a matter of preference to write
8152 -- "Expr = True" or "Expr".
8154 if Warn_On_Redundant_Constructs
8155 and then Comes_From_Source
(N
)
8156 and then Comes_From_Source
(R
)
8157 and then Is_Entity_Name
(R
)
8158 and then Entity
(R
) = Standard_True
8160 ((Is_Entity_Name
(L
) and then Is_Object
(Entity
(L
)))
8164 Error_Msg_N
-- CODEFIX
8165 ("?r?comparison with True is redundant!", N
);
8166 Explain_Redundancy
(Original_Node
(R
));
8169 Check_Unset_Reference
(L
);
8170 Check_Unset_Reference
(R
);
8171 Generate_Operator_Reference
(N
, T
);
8172 Check_Low_Bound_Tested
(N
);
8174 -- If this is an inequality, it may be the implicit inequality
8175 -- created for a user-defined operation, in which case the corres-
8176 -- ponding equality operation is not intrinsic, and the operation
8177 -- cannot be constant-folded. Else fold.
8179 if Nkind
(N
) = N_Op_Eq
8180 or else Comes_From_Source
(Entity
(N
))
8181 or else Ekind
(Entity
(N
)) = E_Operator
8182 or else Is_Intrinsic_Subprogram
8183 (Corresponding_Equality
(Entity
(N
)))
8185 Analyze_Dimension
(N
);
8186 Eval_Relational_Op
(N
);
8188 elsif Nkind
(N
) = N_Op_Ne
8189 and then Is_Abstract_Subprogram
(Entity
(N
))
8191 Error_Msg_NE
("cannot call abstract subprogram &!", N
, Entity
(N
));
8194 -- Ada 2005: If one operand is an anonymous access type, convert the
8195 -- other operand to it, to ensure that the underlying types match in
8196 -- the back-end. Same for access_to_subprogram, and the conversion
8197 -- verifies that the types are subtype conformant.
8199 -- We apply the same conversion in the case one of the operands is a
8200 -- private subtype of the type of the other.
8202 -- Why the Expander_Active test here ???
8206 (Ekind_In
(T
, E_Anonymous_Access_Type
,
8207 E_Anonymous_Access_Subprogram_Type
)
8208 or else Is_Private_Type
(T
))
8210 if Etype
(L
) /= T
then
8212 Make_Unchecked_Type_Conversion
(Sloc
(L
),
8213 Subtype_Mark
=> New_Occurrence_Of
(T
, Sloc
(L
)),
8214 Expression
=> Relocate_Node
(L
)));
8215 Analyze_And_Resolve
(L
, T
);
8218 if (Etype
(R
)) /= T
then
8220 Make_Unchecked_Type_Conversion
(Sloc
(R
),
8221 Subtype_Mark
=> New_Occurrence_Of
(Etype
(L
), Sloc
(R
)),
8222 Expression
=> Relocate_Node
(R
)));
8223 Analyze_And_Resolve
(R
, T
);
8227 end Resolve_Equality_Op
;
8229 ----------------------------------
8230 -- Resolve_Explicit_Dereference --
8231 ----------------------------------
8233 procedure Resolve_Explicit_Dereference
(N
: Node_Id
; Typ
: Entity_Id
) is
8234 Loc
: constant Source_Ptr
:= Sloc
(N
);
8236 P
: constant Node_Id
:= Prefix
(N
);
8239 -- The candidate prefix type, if overloaded
8245 Check_Fully_Declared_Prefix
(Typ
, P
);
8248 -- A useful optimization: check whether the dereference denotes an
8249 -- element of a container, and if so rewrite it as a call to the
8250 -- corresponding Element function.
8252 -- Disabled for now, on advice of ARG. A more restricted form of the
8253 -- predicate might be acceptable ???
8255 -- if Is_Container_Element (N) then
8259 if Is_Overloaded
(P
) then
8261 -- Use the context type to select the prefix that has the correct
8262 -- designated type. Keep the first match, which will be the inner-
8265 Get_First_Interp
(P
, I
, It
);
8267 while Present
(It
.Typ
) loop
8268 if Is_Access_Type
(It
.Typ
)
8269 and then Covers
(Typ
, Designated_Type
(It
.Typ
))
8275 -- Remove access types that do not match, but preserve access
8276 -- to subprogram interpretations, in case a further dereference
8277 -- is needed (see below).
8279 elsif Ekind
(It
.Typ
) /= E_Access_Subprogram_Type
then
8283 Get_Next_Interp
(I
, It
);
8286 if Present
(P_Typ
) then
8288 Set_Etype
(N
, Designated_Type
(P_Typ
));
8291 -- If no interpretation covers the designated type of the prefix,
8292 -- this is the pathological case where not all implementations of
8293 -- the prefix allow the interpretation of the node as a call. Now
8294 -- that the expected type is known, Remove other interpretations
8295 -- from prefix, rewrite it as a call, and resolve again, so that
8296 -- the proper call node is generated.
8298 Get_First_Interp
(P
, I
, It
);
8299 while Present
(It
.Typ
) loop
8300 if Ekind
(It
.Typ
) /= E_Access_Subprogram_Type
then
8304 Get_Next_Interp
(I
, It
);
8308 Make_Function_Call
(Loc
,
8310 Make_Explicit_Dereference
(Loc
,
8312 Parameter_Associations
=> New_List
);
8314 Save_Interps
(N
, New_N
);
8316 Analyze_And_Resolve
(N
, Typ
);
8320 -- If not overloaded, resolve P with its own type
8326 -- If the prefix might be null, add an access check
8328 if Is_Access_Type
(Etype
(P
))
8329 and then not Can_Never_Be_Null
(Etype
(P
))
8331 Apply_Access_Check
(N
);
8334 -- If the designated type is a packed unconstrained array type, and the
8335 -- explicit dereference is not in the context of an attribute reference,
8336 -- then we must compute and set the actual subtype, since it is needed
8337 -- by Gigi. The reason we exclude the attribute case is that this is
8338 -- handled fine by Gigi, and in fact we use such attributes to build the
8339 -- actual subtype. We also exclude generated code (which builds actual
8340 -- subtypes directly if they are needed).
8342 if Is_Array_Type
(Etype
(N
))
8343 and then Is_Packed
(Etype
(N
))
8344 and then not Is_Constrained
(Etype
(N
))
8345 and then Nkind
(Parent
(N
)) /= N_Attribute_Reference
8346 and then Comes_From_Source
(N
)
8348 Set_Etype
(N
, Get_Actual_Subtype
(N
));
8351 Analyze_Dimension
(N
);
8353 -- Note: No Eval processing is required for an explicit dereference,
8354 -- because such a name can never be static.
8356 end Resolve_Explicit_Dereference
;
8358 -------------------------------------
8359 -- Resolve_Expression_With_Actions --
8360 -------------------------------------
8362 procedure Resolve_Expression_With_Actions
(N
: Node_Id
; Typ
: Entity_Id
) is
8366 -- If N has no actions, and its expression has been constant folded,
8367 -- then rewrite N as just its expression. Note, we can't do this in
8368 -- the general case of Is_Empty_List (Actions (N)) as this would cause
8369 -- Expression (N) to be expanded again.
8371 if Is_Empty_List
(Actions
(N
))
8372 and then Compile_Time_Known_Value
(Expression
(N
))
8374 Rewrite
(N
, Expression
(N
));
8376 end Resolve_Expression_With_Actions
;
8378 ----------------------------------
8379 -- Resolve_Generalized_Indexing --
8380 ----------------------------------
8382 procedure Resolve_Generalized_Indexing
(N
: Node_Id
; Typ
: Entity_Id
) is
8383 Indexing
: constant Node_Id
:= Generalized_Indexing
(N
);
8389 -- In ASIS mode, propagate the information about the indexes back to
8390 -- to the original indexing node. The generalized indexing is either
8391 -- a function call, or a dereference of one. The actuals include the
8392 -- prefix of the original node, which is the container expression.
8395 Resolve
(Indexing
, Typ
);
8396 Set_Etype
(N
, Etype
(Indexing
));
8397 Set_Is_Overloaded
(N
, False);
8400 while Nkind_In
(Call
, N_Explicit_Dereference
, N_Selected_Component
)
8402 Call
:= Prefix
(Call
);
8405 if Nkind
(Call
) = N_Function_Call
then
8406 Indexes
:= New_Copy_List
(Parameter_Associations
(Call
));
8407 Pref
:= Remove_Head
(Indexes
);
8408 Set_Expressions
(N
, Indexes
);
8410 -- If expression is to be reanalyzed, reset Generalized_Indexing
8411 -- to recreate call node, as is the case when the expression is
8412 -- part of an expression function.
8414 if In_Spec_Expression
then
8415 Set_Generalized_Indexing
(N
, Empty
);
8418 Set_Prefix
(N
, Pref
);
8422 Rewrite
(N
, Indexing
);
8425 end Resolve_Generalized_Indexing
;
8427 ---------------------------
8428 -- Resolve_If_Expression --
8429 ---------------------------
8431 procedure Resolve_If_Expression
(N
: Node_Id
; Typ
: Entity_Id
) is
8432 Condition
: constant Node_Id
:= First
(Expressions
(N
));
8433 Then_Expr
: Node_Id
;
8434 Else_Expr
: Node_Id
;
8435 Else_Typ
: Entity_Id
;
8436 Then_Typ
: Entity_Id
;
8439 -- Defend against malformed expressions
8441 if No
(Condition
) then
8445 Then_Expr
:= Next
(Condition
);
8447 if No
(Then_Expr
) then
8451 Else_Expr
:= Next
(Then_Expr
);
8453 Resolve
(Condition
, Any_Boolean
);
8454 Resolve
(Then_Expr
, Typ
);
8455 Then_Typ
:= Etype
(Then_Expr
);
8457 -- When the "then" expression is of a scalar subtype different from the
8458 -- result subtype, then insert a conversion to ensure the generation of
8459 -- a constraint check. The same is done for the else part below, again
8460 -- comparing subtypes rather than base types.
8462 if Is_Scalar_Type
(Then_Typ
) and then Then_Typ
/= Typ
then
8463 Rewrite
(Then_Expr
, Convert_To
(Typ
, Then_Expr
));
8464 Analyze_And_Resolve
(Then_Expr
, Typ
);
8467 -- If ELSE expression present, just resolve using the determined type
8468 -- If type is universal, resolve to any member of the class.
8470 if Present
(Else_Expr
) then
8471 if Typ
= Universal_Integer
then
8472 Resolve
(Else_Expr
, Any_Integer
);
8474 elsif Typ
= Universal_Real
then
8475 Resolve
(Else_Expr
, Any_Real
);
8478 Resolve
(Else_Expr
, Typ
);
8481 Else_Typ
:= Etype
(Else_Expr
);
8483 if Is_Scalar_Type
(Else_Typ
) and then Else_Typ
/= Typ
then
8484 Rewrite
(Else_Expr
, Convert_To
(Typ
, Else_Expr
));
8485 Analyze_And_Resolve
(Else_Expr
, Typ
);
8487 -- Apply RM 4.5.7 (17/3): whether the expression is statically or
8488 -- dynamically tagged must be known statically.
8490 elsif Is_Tagged_Type
(Typ
) and then not Is_Class_Wide_Type
(Typ
) then
8491 if Is_Dynamically_Tagged
(Then_Expr
) /=
8492 Is_Dynamically_Tagged
(Else_Expr
)
8494 Error_Msg_N
("all or none of the dependent expressions "
8495 & "can be dynamically tagged", N
);
8499 -- If no ELSE expression is present, root type must be Standard.Boolean
8500 -- and we provide a Standard.True result converted to the appropriate
8501 -- Boolean type (in case it is a derived boolean type).
8503 elsif Root_Type
(Typ
) = Standard_Boolean
then
8505 Convert_To
(Typ
, New_Occurrence_Of
(Standard_True
, Sloc
(N
)));
8506 Analyze_And_Resolve
(Else_Expr
, Typ
);
8507 Append_To
(Expressions
(N
), Else_Expr
);
8510 Error_Msg_N
("can only omit ELSE expression in Boolean case", N
);
8511 Append_To
(Expressions
(N
), Error
);
8516 if not Error_Posted
(N
) then
8517 Eval_If_Expression
(N
);
8520 Analyze_Dimension
(N
);
8521 end Resolve_If_Expression
;
8523 -------------------------------
8524 -- Resolve_Indexed_Component --
8525 -------------------------------
8527 procedure Resolve_Indexed_Component
(N
: Node_Id
; Typ
: Entity_Id
) is
8528 Name
: constant Node_Id
:= Prefix
(N
);
8530 Array_Type
: Entity_Id
:= Empty
; -- to prevent junk warning
8534 if Present
(Generalized_Indexing
(N
)) then
8535 Resolve_Generalized_Indexing
(N
, Typ
);
8539 if Is_Overloaded
(Name
) then
8541 -- Use the context type to select the prefix that yields the correct
8547 I1
: Interp_Index
:= 0;
8548 P
: constant Node_Id
:= Prefix
(N
);
8549 Found
: Boolean := False;
8552 Get_First_Interp
(P
, I
, It
);
8553 while Present
(It
.Typ
) loop
8554 if (Is_Array_Type
(It
.Typ
)
8555 and then Covers
(Typ
, Component_Type
(It
.Typ
)))
8556 or else (Is_Access_Type
(It
.Typ
)
8557 and then Is_Array_Type
(Designated_Type
(It
.Typ
))
8561 Component_Type
(Designated_Type
(It
.Typ
))))
8564 It
:= Disambiguate
(P
, I1
, I
, Any_Type
);
8566 if It
= No_Interp
then
8567 Error_Msg_N
("ambiguous prefix for indexing", N
);
8573 Array_Type
:= It
.Typ
;
8579 Array_Type
:= It
.Typ
;
8584 Get_Next_Interp
(I
, It
);
8589 Array_Type
:= Etype
(Name
);
8592 Resolve
(Name
, Array_Type
);
8593 Array_Type
:= Get_Actual_Subtype_If_Available
(Name
);
8595 -- If prefix is access type, dereference to get real array type.
8596 -- Note: we do not apply an access check because the expander always
8597 -- introduces an explicit dereference, and the check will happen there.
8599 if Is_Access_Type
(Array_Type
) then
8600 Array_Type
:= Designated_Type
(Array_Type
);
8603 -- If name was overloaded, set component type correctly now
8604 -- If a misplaced call to an entry family (which has no index types)
8605 -- return. Error will be diagnosed from calling context.
8607 if Is_Array_Type
(Array_Type
) then
8608 Set_Etype
(N
, Component_Type
(Array_Type
));
8613 Index
:= First_Index
(Array_Type
);
8614 Expr
:= First
(Expressions
(N
));
8616 -- The prefix may have resolved to a string literal, in which case its
8617 -- etype has a special representation. This is only possible currently
8618 -- if the prefix is a static concatenation, written in functional
8621 if Ekind
(Array_Type
) = E_String_Literal_Subtype
then
8622 Resolve
(Expr
, Standard_Positive
);
8625 while Present
(Index
) and Present
(Expr
) loop
8626 Resolve
(Expr
, Etype
(Index
));
8627 Check_Unset_Reference
(Expr
);
8629 if Is_Scalar_Type
(Etype
(Expr
)) then
8630 Apply_Scalar_Range_Check
(Expr
, Etype
(Index
));
8632 Apply_Range_Check
(Expr
, Get_Actual_Subtype
(Index
));
8640 Analyze_Dimension
(N
);
8642 -- Do not generate the warning on suspicious index if we are analyzing
8643 -- package Ada.Tags; otherwise we will report the warning with the
8644 -- Prims_Ptr field of the dispatch table.
8646 if Scope
(Etype
(Prefix
(N
))) = Standard_Standard
8648 Is_RTU
(Cunit_Entity
(Get_Source_Unit
(Etype
(Prefix
(N
)))),
8651 Warn_On_Suspicious_Index
(Name
, First
(Expressions
(N
)));
8652 Eval_Indexed_Component
(N
);
8655 -- If the array type is atomic, and the component is not atomic, then
8656 -- this is worth a warning, since we have a situation where the access
8657 -- to the component may cause extra read/writes of the atomic array
8658 -- object, or partial word accesses, which could be unexpected.
8660 if Nkind
(N
) = N_Indexed_Component
8661 and then Is_Atomic_Ref_With_Address
(N
)
8662 and then not (Has_Atomic_Components
(Array_Type
)
8663 or else (Is_Entity_Name
(Prefix
(N
))
8664 and then Has_Atomic_Components
8665 (Entity
(Prefix
(N
)))))
8666 and then not Is_Atomic
(Component_Type
(Array_Type
))
8669 ("??access to non-atomic component of atomic array", Prefix
(N
));
8671 ("??\may cause unexpected accesses to atomic object", Prefix
(N
));
8673 end Resolve_Indexed_Component
;
8675 -----------------------------
8676 -- Resolve_Integer_Literal --
8677 -----------------------------
8679 procedure Resolve_Integer_Literal
(N
: Node_Id
; Typ
: Entity_Id
) is
8682 Eval_Integer_Literal
(N
);
8683 end Resolve_Integer_Literal
;
8685 --------------------------------
8686 -- Resolve_Intrinsic_Operator --
8687 --------------------------------
8689 procedure Resolve_Intrinsic_Operator
(N
: Node_Id
; Typ
: Entity_Id
) is
8690 Btyp
: constant Entity_Id
:= Base_Type
(Underlying_Type
(Typ
));
8695 function Convert_Operand
(Opnd
: Node_Id
) return Node_Id
;
8696 -- If the operand is a literal, it cannot be the expression in a
8697 -- conversion. Use a qualified expression instead.
8699 ---------------------
8700 -- Convert_Operand --
8701 ---------------------
8703 function Convert_Operand
(Opnd
: Node_Id
) return Node_Id
is
8704 Loc
: constant Source_Ptr
:= Sloc
(Opnd
);
8708 if Nkind_In
(Opnd
, N_Integer_Literal
, N_Real_Literal
) then
8710 Make_Qualified_Expression
(Loc
,
8711 Subtype_Mark
=> New_Occurrence_Of
(Btyp
, Loc
),
8712 Expression
=> Relocate_Node
(Opnd
));
8716 Res
:= Unchecked_Convert_To
(Btyp
, Opnd
);
8720 end Convert_Operand
;
8722 -- Start of processing for Resolve_Intrinsic_Operator
8725 -- We must preserve the original entity in a generic setting, so that
8726 -- the legality of the operation can be verified in an instance.
8728 if not Expander_Active
then
8733 while Scope
(Op
) /= Standard_Standard
loop
8735 pragma Assert
(Present
(Op
));
8739 Set_Is_Overloaded
(N
, False);
8741 -- If the result or operand types are private, rewrite with unchecked
8742 -- conversions on the operands and the result, to expose the proper
8743 -- underlying numeric type.
8745 if Is_Private_Type
(Typ
)
8746 or else Is_Private_Type
(Etype
(Left_Opnd
(N
)))
8747 or else Is_Private_Type
(Etype
(Right_Opnd
(N
)))
8749 Arg1
:= Convert_Operand
(Left_Opnd
(N
));
8751 if Nkind
(N
) = N_Op_Expon
then
8752 Arg2
:= Unchecked_Convert_To
(Standard_Integer
, Right_Opnd
(N
));
8754 Arg2
:= Convert_Operand
(Right_Opnd
(N
));
8757 if Nkind
(Arg1
) = N_Type_Conversion
then
8758 Save_Interps
(Left_Opnd
(N
), Expression
(Arg1
));
8761 if Nkind
(Arg2
) = N_Type_Conversion
then
8762 Save_Interps
(Right_Opnd
(N
), Expression
(Arg2
));
8765 Set_Left_Opnd
(N
, Arg1
);
8766 Set_Right_Opnd
(N
, Arg2
);
8768 Set_Etype
(N
, Btyp
);
8769 Rewrite
(N
, Unchecked_Convert_To
(Typ
, N
));
8772 elsif Typ
/= Etype
(Left_Opnd
(N
))
8773 or else Typ
/= Etype
(Right_Opnd
(N
))
8775 -- Add explicit conversion where needed, and save interpretations in
8776 -- case operands are overloaded.
8778 Arg1
:= Convert_To
(Typ
, Left_Opnd
(N
));
8779 Arg2
:= Convert_To
(Typ
, Right_Opnd
(N
));
8781 if Nkind
(Arg1
) = N_Type_Conversion
then
8782 Save_Interps
(Left_Opnd
(N
), Expression
(Arg1
));
8784 Save_Interps
(Left_Opnd
(N
), Arg1
);
8787 if Nkind
(Arg2
) = N_Type_Conversion
then
8788 Save_Interps
(Right_Opnd
(N
), Expression
(Arg2
));
8790 Save_Interps
(Right_Opnd
(N
), Arg2
);
8793 Rewrite
(Left_Opnd
(N
), Arg1
);
8794 Rewrite
(Right_Opnd
(N
), Arg2
);
8797 Resolve_Arithmetic_Op
(N
, Typ
);
8800 Resolve_Arithmetic_Op
(N
, Typ
);
8802 end Resolve_Intrinsic_Operator
;
8804 --------------------------------------
8805 -- Resolve_Intrinsic_Unary_Operator --
8806 --------------------------------------
8808 procedure Resolve_Intrinsic_Unary_Operator
8812 Btyp
: constant Entity_Id
:= Base_Type
(Underlying_Type
(Typ
));
8818 while Scope
(Op
) /= Standard_Standard
loop
8820 pragma Assert
(Present
(Op
));
8825 if Is_Private_Type
(Typ
) then
8826 Arg2
:= Unchecked_Convert_To
(Btyp
, Right_Opnd
(N
));
8827 Save_Interps
(Right_Opnd
(N
), Expression
(Arg2
));
8829 Set_Right_Opnd
(N
, Arg2
);
8831 Set_Etype
(N
, Btyp
);
8832 Rewrite
(N
, Unchecked_Convert_To
(Typ
, N
));
8836 Resolve_Unary_Op
(N
, Typ
);
8838 end Resolve_Intrinsic_Unary_Operator
;
8840 ------------------------
8841 -- Resolve_Logical_Op --
8842 ------------------------
8844 procedure Resolve_Logical_Op
(N
: Node_Id
; Typ
: Entity_Id
) is
8848 Check_No_Direct_Boolean_Operators
(N
);
8850 -- Predefined operations on scalar types yield the base type. On the
8851 -- other hand, logical operations on arrays yield the type of the
8852 -- arguments (and the context).
8854 if Is_Array_Type
(Typ
) then
8857 B_Typ
:= Base_Type
(Typ
);
8860 -- The following test is required because the operands of the operation
8861 -- may be literals, in which case the resulting type appears to be
8862 -- compatible with a signed integer type, when in fact it is compatible
8863 -- only with modular types. If the context itself is universal, the
8864 -- operation is illegal.
8866 if not Valid_Boolean_Arg
(Typ
) then
8867 Error_Msg_N
("invalid context for logical operation", N
);
8868 Set_Etype
(N
, Any_Type
);
8871 elsif Typ
= Any_Modular
then
8873 ("no modular type available in this context", N
);
8874 Set_Etype
(N
, Any_Type
);
8877 elsif Is_Modular_Integer_Type
(Typ
)
8878 and then Etype
(Left_Opnd
(N
)) = Universal_Integer
8879 and then Etype
(Right_Opnd
(N
)) = Universal_Integer
8881 Check_For_Visible_Operator
(N
, B_Typ
);
8884 -- Replace AND by AND THEN, or OR by OR ELSE, if Short_Circuit_And_Or
8885 -- is active and the result type is standard Boolean (do not mess with
8886 -- ops that return a nonstandard Boolean type, because something strange
8889 -- Note: you might expect this replacement to be done during expansion,
8890 -- but that doesn't work, because when the pragma Short_Circuit_And_Or
8891 -- is used, no part of the right operand of an "and" or "or" operator
8892 -- should be executed if the left operand would short-circuit the
8893 -- evaluation of the corresponding "and then" or "or else". If we left
8894 -- the replacement to expansion time, then run-time checks associated
8895 -- with such operands would be evaluated unconditionally, due to being
8896 -- before the condition prior to the rewriting as short-circuit forms
8897 -- during expansion.
8899 if Short_Circuit_And_Or
8900 and then B_Typ
= Standard_Boolean
8901 and then Nkind_In
(N
, N_Op_And
, N_Op_Or
)
8903 -- Mark the corresponding putative SCO operator as truly a logical
8904 -- (and short-circuit) operator.
8906 if Generate_SCO
and then Comes_From_Source
(N
) then
8907 Set_SCO_Logical_Operator
(N
);
8910 if Nkind
(N
) = N_Op_And
then
8912 Make_And_Then
(Sloc
(N
),
8913 Left_Opnd
=> Relocate_Node
(Left_Opnd
(N
)),
8914 Right_Opnd
=> Relocate_Node
(Right_Opnd
(N
))));
8915 Analyze_And_Resolve
(N
, B_Typ
);
8917 -- Case of OR changed to OR ELSE
8921 Make_Or_Else
(Sloc
(N
),
8922 Left_Opnd
=> Relocate_Node
(Left_Opnd
(N
)),
8923 Right_Opnd
=> Relocate_Node
(Right_Opnd
(N
))));
8924 Analyze_And_Resolve
(N
, B_Typ
);
8927 -- Return now, since analysis of the rewritten ops will take care of
8928 -- other reference bookkeeping and expression folding.
8933 Resolve
(Left_Opnd
(N
), B_Typ
);
8934 Resolve
(Right_Opnd
(N
), B_Typ
);
8936 Check_Unset_Reference
(Left_Opnd
(N
));
8937 Check_Unset_Reference
(Right_Opnd
(N
));
8939 Set_Etype
(N
, B_Typ
);
8940 Generate_Operator_Reference
(N
, B_Typ
);
8941 Eval_Logical_Op
(N
);
8943 -- In SPARK, logical operations AND, OR and XOR for arrays are defined
8944 -- only when both operands have same static lower and higher bounds. Of
8945 -- course the types have to match, so only check if operands are
8946 -- compatible and the node itself has no errors.
8948 if Is_Array_Type
(B_Typ
)
8949 and then Nkind
(N
) in N_Binary_Op
8952 Left_Typ
: constant Node_Id
:= Etype
(Left_Opnd
(N
));
8953 Right_Typ
: constant Node_Id
:= Etype
(Right_Opnd
(N
));
8956 -- Protect call to Matching_Static_Array_Bounds to avoid costly
8957 -- operation if not needed.
8959 if Restriction_Check_Required
(SPARK_05
)
8960 and then Base_Type
(Left_Typ
) = Base_Type
(Right_Typ
)
8961 and then Left_Typ
/= Any_Composite
-- or Left_Opnd in error
8962 and then Right_Typ
/= Any_Composite
-- or Right_Opnd in error
8963 and then not Matching_Static_Array_Bounds
(Left_Typ
, Right_Typ
)
8965 Check_SPARK_05_Restriction
8966 ("array types should have matching static bounds", N
);
8970 end Resolve_Logical_Op
;
8972 ---------------------------
8973 -- Resolve_Membership_Op --
8974 ---------------------------
8976 -- The context can only be a boolean type, and does not determine the
8977 -- arguments. Arguments should be unambiguous, but the preference rule for
8978 -- universal types applies.
8980 procedure Resolve_Membership_Op
(N
: Node_Id
; Typ
: Entity_Id
) is
8981 pragma Warnings
(Off
, Typ
);
8983 L
: constant Node_Id
:= Left_Opnd
(N
);
8984 R
: constant Node_Id
:= Right_Opnd
(N
);
8987 procedure Resolve_Set_Membership
;
8988 -- Analysis has determined a unique type for the left operand. Use it to
8989 -- resolve the disjuncts.
8991 ----------------------------
8992 -- Resolve_Set_Membership --
8993 ----------------------------
8995 procedure Resolve_Set_Membership
is
9000 -- If the left operand is overloaded, find type compatible with not
9001 -- overloaded alternative of the right operand.
9003 if Is_Overloaded
(L
) then
9005 Alt
:= First
(Alternatives
(N
));
9006 while Present
(Alt
) loop
9007 if not Is_Overloaded
(Alt
) then
9008 Ltyp
:= Intersect_Types
(L
, Alt
);
9015 -- Unclear how to resolve expression if all alternatives are also
9019 Error_Msg_N
("ambiguous expression", N
);
9028 Alt
:= First
(Alternatives
(N
));
9029 while Present
(Alt
) loop
9031 -- Alternative is an expression, a range
9032 -- or a subtype mark.
9034 if not Is_Entity_Name
(Alt
)
9035 or else not Is_Type
(Entity
(Alt
))
9037 Resolve
(Alt
, Ltyp
);
9043 -- Check for duplicates for discrete case
9045 if Is_Discrete_Type
(Ltyp
) then
9052 Alts
: array (0 .. List_Length
(Alternatives
(N
))) of Ent
;
9056 -- Loop checking duplicates. This is quadratic, but giant sets
9057 -- are unlikely in this context so it's a reasonable choice.
9060 Alt
:= First
(Alternatives
(N
));
9061 while Present
(Alt
) loop
9062 if Is_OK_Static_Expression
(Alt
)
9063 and then (Nkind_In
(Alt
, N_Integer_Literal
,
9064 N_Character_Literal
)
9065 or else Nkind
(Alt
) in N_Has_Entity
)
9068 Alts
(Nalts
) := (Alt
, Expr_Value
(Alt
));
9070 for J
in 1 .. Nalts
- 1 loop
9071 if Alts
(J
).Val
= Alts
(Nalts
).Val
then
9072 Error_Msg_Sloc
:= Sloc
(Alts
(J
).Alt
);
9073 Error_Msg_N
("duplicate of value given#??", Alt
);
9082 end Resolve_Set_Membership
;
9084 -- Start of processing for Resolve_Membership_Op
9087 if L
= Error
or else R
= Error
then
9091 if Present
(Alternatives
(N
)) then
9092 Resolve_Set_Membership
;
9095 elsif not Is_Overloaded
(R
)
9097 (Etype
(R
) = Universal_Integer
9099 Etype
(R
) = Universal_Real
)
9100 and then Is_Overloaded
(L
)
9104 -- Ada 2005 (AI-251): Support the following case:
9106 -- type I is interface;
9107 -- type T is tagged ...
9109 -- function Test (O : I'Class) is
9111 -- return O in T'Class.
9114 -- In this case we have nothing else to do. The membership test will be
9115 -- done at run time.
9117 elsif Ada_Version
>= Ada_2005
9118 and then Is_Class_Wide_Type
(Etype
(L
))
9119 and then Is_Interface
(Etype
(L
))
9120 and then Is_Class_Wide_Type
(Etype
(R
))
9121 and then not Is_Interface
(Etype
(R
))
9125 T
:= Intersect_Types
(L
, R
);
9128 -- If mixed-mode operations are present and operands are all literal,
9129 -- the only interpretation involves Duration, which is probably not
9130 -- the intention of the programmer.
9132 if T
= Any_Fixed
then
9133 T
:= Unique_Fixed_Point_Type
(N
);
9135 if T
= Any_Type
then
9141 Check_Unset_Reference
(L
);
9143 if Nkind
(R
) = N_Range
9144 and then not Is_Scalar_Type
(T
)
9146 Error_Msg_N
("scalar type required for range", R
);
9149 if Is_Entity_Name
(R
) then
9150 Freeze_Expression
(R
);
9153 Check_Unset_Reference
(R
);
9156 -- Here after resolving membership operation
9160 Eval_Membership_Op
(N
);
9161 end Resolve_Membership_Op
;
9167 procedure Resolve_Null
(N
: Node_Id
; Typ
: Entity_Id
) is
9168 Loc
: constant Source_Ptr
:= Sloc
(N
);
9171 -- Handle restriction against anonymous null access values This
9172 -- restriction can be turned off using -gnatdj.
9174 -- Ada 2005 (AI-231): Remove restriction
9176 if Ada_Version
< Ada_2005
9177 and then not Debug_Flag_J
9178 and then Ekind
(Typ
) = E_Anonymous_Access_Type
9179 and then Comes_From_Source
(N
)
9181 -- In the common case of a call which uses an explicitly null value
9182 -- for an access parameter, give specialized error message.
9184 if Nkind
(Parent
(N
)) in N_Subprogram_Call
then
9186 ("null is not allowed as argument for an access parameter", N
);
9188 -- Standard message for all other cases (are there any?)
9192 ("null cannot be of an anonymous access type", N
);
9196 -- Ada 2005 (AI-231): Generate the null-excluding check in case of
9197 -- assignment to a null-excluding object
9199 if Ada_Version
>= Ada_2005
9200 and then Can_Never_Be_Null
(Typ
)
9201 and then Nkind
(Parent
(N
)) = N_Assignment_Statement
9203 if not Inside_Init_Proc
then
9205 (Compile_Time_Constraint_Error
(N
,
9206 "(Ada 2005) null not allowed in null-excluding objects??"),
9207 Make_Raise_Constraint_Error
(Loc
,
9208 Reason
=> CE_Access_Check_Failed
));
9211 Make_Raise_Constraint_Error
(Loc
,
9212 Reason
=> CE_Access_Check_Failed
));
9216 -- In a distributed context, null for a remote access to subprogram may
9217 -- need to be replaced with a special record aggregate. In this case,
9218 -- return after having done the transformation.
9220 if (Ekind
(Typ
) = E_Record_Type
9221 or else Is_Remote_Access_To_Subprogram_Type
(Typ
))
9222 and then Remote_AST_Null_Value
(N
, Typ
)
9227 -- The null literal takes its type from the context
9232 -----------------------
9233 -- Resolve_Op_Concat --
9234 -----------------------
9236 procedure Resolve_Op_Concat
(N
: Node_Id
; Typ
: Entity_Id
) is
9238 -- We wish to avoid deep recursion, because concatenations are often
9239 -- deeply nested, as in A&B&...&Z. Therefore, we walk down the left
9240 -- operands nonrecursively until we find something that is not a simple
9241 -- concatenation (A in this case). We resolve that, and then walk back
9242 -- up the tree following Parent pointers, calling Resolve_Op_Concat_Rest
9243 -- to do the rest of the work at each level. The Parent pointers allow
9244 -- us to avoid recursion, and thus avoid running out of memory. See also
9245 -- Sem_Ch4.Analyze_Concatenation, where a similar approach is used.
9251 -- The following code is equivalent to:
9253 -- Resolve_Op_Concat_First (NN, Typ);
9254 -- Resolve_Op_Concat_Arg (N, ...);
9255 -- Resolve_Op_Concat_Rest (N, Typ);
9257 -- where the Resolve_Op_Concat_Arg call recurses back here if the left
9258 -- operand is a concatenation.
9260 -- Walk down left operands
9263 Resolve_Op_Concat_First
(NN
, Typ
);
9264 Op1
:= Left_Opnd
(NN
);
9265 exit when not (Nkind
(Op1
) = N_Op_Concat
9266 and then not Is_Array_Type
(Component_Type
(Typ
))
9267 and then Entity
(Op1
) = Entity
(NN
));
9271 -- Now (given the above example) NN is A&B and Op1 is A
9273 -- First resolve Op1 ...
9275 Resolve_Op_Concat_Arg
(NN
, Op1
, Typ
, Is_Component_Left_Opnd
(NN
));
9277 -- ... then walk NN back up until we reach N (where we started), calling
9278 -- Resolve_Op_Concat_Rest along the way.
9281 Resolve_Op_Concat_Rest
(NN
, Typ
);
9286 if Base_Type
(Etype
(N
)) /= Standard_String
then
9287 Check_SPARK_05_Restriction
9288 ("result of concatenation should have type String", N
);
9290 end Resolve_Op_Concat
;
9292 ---------------------------
9293 -- Resolve_Op_Concat_Arg --
9294 ---------------------------
9296 procedure Resolve_Op_Concat_Arg
9302 Btyp
: constant Entity_Id
:= Base_Type
(Typ
);
9303 Ctyp
: constant Entity_Id
:= Component_Type
(Typ
);
9308 or else (not Is_Overloaded
(Arg
)
9309 and then Etype
(Arg
) /= Any_Composite
9310 and then Covers
(Ctyp
, Etype
(Arg
)))
9312 Resolve
(Arg
, Ctyp
);
9314 Resolve
(Arg
, Btyp
);
9317 -- If both Array & Array and Array & Component are visible, there is a
9318 -- potential ambiguity that must be reported.
9320 elsif Has_Compatible_Type
(Arg
, Ctyp
) then
9321 if Nkind
(Arg
) = N_Aggregate
9322 and then Is_Composite_Type
(Ctyp
)
9324 if Is_Private_Type
(Ctyp
) then
9325 Resolve
(Arg
, Btyp
);
9327 -- If the operation is user-defined and not overloaded use its
9328 -- profile. The operation may be a renaming, in which case it has
9329 -- been rewritten, and we want the original profile.
9331 elsif not Is_Overloaded
(N
)
9332 and then Comes_From_Source
(Entity
(Original_Node
(N
)))
9333 and then Ekind
(Entity
(Original_Node
(N
))) = E_Function
9337 (Next_Formal
(First_Formal
(Entity
(Original_Node
(N
))))));
9340 -- Otherwise an aggregate may match both the array type and the
9344 Error_Msg_N
("ambiguous aggregate must be qualified", Arg
);
9345 Set_Etype
(Arg
, Any_Type
);
9349 if Is_Overloaded
(Arg
)
9350 and then Has_Compatible_Type
(Arg
, Typ
)
9351 and then Etype
(Arg
) /= Any_Type
9359 Get_First_Interp
(Arg
, I
, It
);
9361 Get_Next_Interp
(I
, It
);
9363 -- Special-case the error message when the overloading is
9364 -- caused by a function that yields an array and can be
9365 -- called without parameters.
9367 if It
.Nam
= Func
then
9368 Error_Msg_Sloc
:= Sloc
(Func
);
9369 Error_Msg_N
("ambiguous call to function#", Arg
);
9371 ("\\interpretation as call yields&", Arg
, Typ
);
9373 ("\\interpretation as indexing of call yields&",
9374 Arg
, Component_Type
(Typ
));
9377 Error_Msg_N
("ambiguous operand for concatenation!", Arg
);
9379 Get_First_Interp
(Arg
, I
, It
);
9380 while Present
(It
.Nam
) loop
9381 Error_Msg_Sloc
:= Sloc
(It
.Nam
);
9383 if Base_Type
(It
.Typ
) = Btyp
9385 Base_Type
(It
.Typ
) = Base_Type
(Ctyp
)
9387 Error_Msg_N
-- CODEFIX
9388 ("\\possible interpretation#", Arg
);
9391 Get_Next_Interp
(I
, It
);
9397 Resolve
(Arg
, Component_Type
(Typ
));
9399 if Nkind
(Arg
) = N_String_Literal
then
9400 Set_Etype
(Arg
, Component_Type
(Typ
));
9403 if Arg
= Left_Opnd
(N
) then
9404 Set_Is_Component_Left_Opnd
(N
);
9406 Set_Is_Component_Right_Opnd
(N
);
9411 Resolve
(Arg
, Btyp
);
9414 -- Concatenation is restricted in SPARK: each operand must be either a
9415 -- string literal, the name of a string constant, a static character or
9416 -- string expression, or another concatenation. Arg cannot be a
9417 -- concatenation here as callers of Resolve_Op_Concat_Arg call it
9418 -- separately on each final operand, past concatenation operations.
9420 if Is_Character_Type
(Etype
(Arg
)) then
9421 if not Is_OK_Static_Expression
(Arg
) then
9422 Check_SPARK_05_Restriction
9423 ("character operand for concatenation should be static", Arg
);
9426 elsif Is_String_Type
(Etype
(Arg
)) then
9427 if not (Nkind_In
(Arg
, N_Identifier
, N_Expanded_Name
)
9428 and then Is_Constant_Object
(Entity
(Arg
)))
9429 and then not Is_OK_Static_Expression
(Arg
)
9431 Check_SPARK_05_Restriction
9432 ("string operand for concatenation should be static", Arg
);
9435 -- Do not issue error on an operand that is neither a character nor a
9436 -- string, as the error is issued in Resolve_Op_Concat.
9442 Check_Unset_Reference
(Arg
);
9443 end Resolve_Op_Concat_Arg
;
9445 -----------------------------
9446 -- Resolve_Op_Concat_First --
9447 -----------------------------
9449 procedure Resolve_Op_Concat_First
(N
: Node_Id
; Typ
: Entity_Id
) is
9450 Btyp
: constant Entity_Id
:= Base_Type
(Typ
);
9451 Op1
: constant Node_Id
:= Left_Opnd
(N
);
9452 Op2
: constant Node_Id
:= Right_Opnd
(N
);
9455 -- The parser folds an enormous sequence of concatenations of string
9456 -- literals into "" & "...", where the Is_Folded_In_Parser flag is set
9457 -- in the right operand. If the expression resolves to a predefined "&"
9458 -- operator, all is well. Otherwise, the parser's folding is wrong, so
9459 -- we give an error. See P_Simple_Expression in Par.Ch4.
9461 if Nkind
(Op2
) = N_String_Literal
9462 and then Is_Folded_In_Parser
(Op2
)
9463 and then Ekind
(Entity
(N
)) = E_Function
9465 pragma Assert
(Nkind
(Op1
) = N_String_Literal
-- should be ""
9466 and then String_Length
(Strval
(Op1
)) = 0);
9467 Error_Msg_N
("too many user-defined concatenations", N
);
9471 Set_Etype
(N
, Btyp
);
9473 if Is_Limited_Composite
(Btyp
) then
9474 Error_Msg_N
("concatenation not available for limited array", N
);
9475 Explain_Limited_Type
(Btyp
, N
);
9477 end Resolve_Op_Concat_First
;
9479 ----------------------------
9480 -- Resolve_Op_Concat_Rest --
9481 ----------------------------
9483 procedure Resolve_Op_Concat_Rest
(N
: Node_Id
; Typ
: Entity_Id
) is
9484 Op1
: constant Node_Id
:= Left_Opnd
(N
);
9485 Op2
: constant Node_Id
:= Right_Opnd
(N
);
9488 Resolve_Op_Concat_Arg
(N
, Op2
, Typ
, Is_Component_Right_Opnd
(N
));
9490 Generate_Operator_Reference
(N
, Typ
);
9492 if Is_String_Type
(Typ
) then
9493 Eval_Concatenation
(N
);
9496 -- If this is not a static concatenation, but the result is a string
9497 -- type (and not an array of strings) ensure that static string operands
9498 -- have their subtypes properly constructed.
9500 if Nkind
(N
) /= N_String_Literal
9501 and then Is_Character_Type
(Component_Type
(Typ
))
9503 Set_String_Literal_Subtype
(Op1
, Typ
);
9504 Set_String_Literal_Subtype
(Op2
, Typ
);
9506 end Resolve_Op_Concat_Rest
;
9508 ----------------------
9509 -- Resolve_Op_Expon --
9510 ----------------------
9512 procedure Resolve_Op_Expon
(N
: Node_Id
; Typ
: Entity_Id
) is
9513 B_Typ
: constant Entity_Id
:= Base_Type
(Typ
);
9516 -- Catch attempts to do fixed-point exponentiation with universal
9517 -- operands, which is a case where the illegality is not caught during
9518 -- normal operator analysis. This is not done in preanalysis mode
9519 -- since the tree is not fully decorated during preanalysis.
9521 if Full_Analysis
then
9522 if Is_Fixed_Point_Type
(Typ
) and then Comes_From_Source
(N
) then
9523 Error_Msg_N
("exponentiation not available for fixed point", N
);
9526 elsif Nkind
(Parent
(N
)) in N_Op
9527 and then Present
(Etype
(Parent
(N
)))
9528 and then Is_Fixed_Point_Type
(Etype
(Parent
(N
)))
9529 and then Etype
(N
) = Universal_Real
9530 and then Comes_From_Source
(N
)
9532 Error_Msg_N
("exponentiation not available for fixed point", N
);
9537 if Comes_From_Source
(N
)
9538 and then Ekind
(Entity
(N
)) = E_Function
9539 and then Is_Imported
(Entity
(N
))
9540 and then Is_Intrinsic_Subprogram
(Entity
(N
))
9542 Resolve_Intrinsic_Operator
(N
, Typ
);
9546 if Etype
(Left_Opnd
(N
)) = Universal_Integer
9547 or else Etype
(Left_Opnd
(N
)) = Universal_Real
9549 Check_For_Visible_Operator
(N
, B_Typ
);
9552 -- We do the resolution using the base type, because intermediate values
9553 -- in expressions are always of the base type, not a subtype of it.
9555 Resolve
(Left_Opnd
(N
), B_Typ
);
9556 Resolve
(Right_Opnd
(N
), Standard_Integer
);
9558 -- For integer types, right argument must be in Natural range
9560 if Is_Integer_Type
(Typ
) then
9561 Apply_Scalar_Range_Check
(Right_Opnd
(N
), Standard_Natural
);
9564 Check_Unset_Reference
(Left_Opnd
(N
));
9565 Check_Unset_Reference
(Right_Opnd
(N
));
9567 Set_Etype
(N
, B_Typ
);
9568 Generate_Operator_Reference
(N
, B_Typ
);
9570 Analyze_Dimension
(N
);
9572 if Ada_Version
>= Ada_2012
and then Has_Dimension_System
(B_Typ
) then
9573 -- Evaluate the exponentiation operator for dimensioned type
9575 Eval_Op_Expon_For_Dimensioned_Type
(N
, B_Typ
);
9580 -- Set overflow checking bit. Much cleverer code needed here eventually
9581 -- and perhaps the Resolve routines should be separated for the various
9582 -- arithmetic operations, since they will need different processing. ???
9584 if Nkind
(N
) in N_Op
then
9585 if not Overflow_Checks_Suppressed
(Etype
(N
)) then
9586 Enable_Overflow_Check
(N
);
9589 end Resolve_Op_Expon
;
9591 --------------------
9592 -- Resolve_Op_Not --
9593 --------------------
9595 procedure Resolve_Op_Not
(N
: Node_Id
; Typ
: Entity_Id
) is
9598 function Parent_Is_Boolean
return Boolean;
9599 -- This function determines if the parent node is a boolean operator or
9600 -- operation (comparison op, membership test, or short circuit form) and
9601 -- the not in question is the left operand of this operation. Note that
9602 -- if the not is in parens, then false is returned.
9604 -----------------------
9605 -- Parent_Is_Boolean --
9606 -----------------------
9608 function Parent_Is_Boolean
return Boolean is
9610 if Paren_Count
(N
) /= 0 then
9614 case Nkind
(Parent
(N
)) is
9629 return Left_Opnd
(Parent
(N
)) = N
;
9635 end Parent_Is_Boolean
;
9637 -- Start of processing for Resolve_Op_Not
9640 -- Predefined operations on scalar types yield the base type. On the
9641 -- other hand, logical operations on arrays yield the type of the
9642 -- arguments (and the context).
9644 if Is_Array_Type
(Typ
) then
9647 B_Typ
:= Base_Type
(Typ
);
9650 -- Straightforward case of incorrect arguments
9652 if not Valid_Boolean_Arg
(Typ
) then
9653 Error_Msg_N
("invalid operand type for operator&", N
);
9654 Set_Etype
(N
, Any_Type
);
9657 -- Special case of probable missing parens
9659 elsif Typ
= Universal_Integer
or else Typ
= Any_Modular
then
9660 if Parent_Is_Boolean
then
9662 ("operand of not must be enclosed in parentheses",
9666 ("no modular type available in this context", N
);
9669 Set_Etype
(N
, Any_Type
);
9672 -- OK resolution of NOT
9675 -- Warn if non-boolean types involved. This is a case like not a < b
9676 -- where a and b are modular, where we will get (not a) < b and most
9677 -- likely not (a < b) was intended.
9679 if Warn_On_Questionable_Missing_Parens
9680 and then not Is_Boolean_Type
(Typ
)
9681 and then Parent_Is_Boolean
9683 Error_Msg_N
("?q?not expression should be parenthesized here!", N
);
9686 -- Warn on double negation if checking redundant constructs
9688 if Warn_On_Redundant_Constructs
9689 and then Comes_From_Source
(N
)
9690 and then Comes_From_Source
(Right_Opnd
(N
))
9691 and then Root_Type
(Typ
) = Standard_Boolean
9692 and then Nkind
(Right_Opnd
(N
)) = N_Op_Not
9694 Error_Msg_N
("redundant double negation?r?", N
);
9697 -- Complete resolution and evaluation of NOT
9699 Resolve
(Right_Opnd
(N
), B_Typ
);
9700 Check_Unset_Reference
(Right_Opnd
(N
));
9701 Set_Etype
(N
, B_Typ
);
9702 Generate_Operator_Reference
(N
, B_Typ
);
9707 -----------------------------
9708 -- Resolve_Operator_Symbol --
9709 -----------------------------
9711 -- Nothing to be done, all resolved already
9713 procedure Resolve_Operator_Symbol
(N
: Node_Id
; Typ
: Entity_Id
) is
9714 pragma Warnings
(Off
, N
);
9715 pragma Warnings
(Off
, Typ
);
9719 end Resolve_Operator_Symbol
;
9721 ----------------------------------
9722 -- Resolve_Qualified_Expression --
9723 ----------------------------------
9725 procedure Resolve_Qualified_Expression
(N
: Node_Id
; Typ
: Entity_Id
) is
9726 pragma Warnings
(Off
, Typ
);
9728 Target_Typ
: constant Entity_Id
:= Entity
(Subtype_Mark
(N
));
9729 Expr
: constant Node_Id
:= Expression
(N
);
9732 Resolve
(Expr
, Target_Typ
);
9734 -- Protect call to Matching_Static_Array_Bounds to avoid costly
9735 -- operation if not needed.
9737 if Restriction_Check_Required
(SPARK_05
)
9738 and then Is_Array_Type
(Target_Typ
)
9739 and then Is_Array_Type
(Etype
(Expr
))
9740 and then Etype
(Expr
) /= Any_Composite
-- or else Expr in error
9741 and then not Matching_Static_Array_Bounds
(Target_Typ
, Etype
(Expr
))
9743 Check_SPARK_05_Restriction
9744 ("array types should have matching static bounds", N
);
9747 -- A qualified expression requires an exact match of the type, class-
9748 -- wide matching is not allowed. However, if the qualifying type is
9749 -- specific and the expression has a class-wide type, it may still be
9750 -- okay, since it can be the result of the expansion of a call to a
9751 -- dispatching function, so we also have to check class-wideness of the
9752 -- type of the expression's original node.
9754 if (Is_Class_Wide_Type
(Target_Typ
)
9756 (Is_Class_Wide_Type
(Etype
(Expr
))
9757 and then Is_Class_Wide_Type
(Etype
(Original_Node
(Expr
)))))
9758 and then Base_Type
(Etype
(Expr
)) /= Base_Type
(Target_Typ
)
9760 Wrong_Type
(Expr
, Target_Typ
);
9763 -- If the target type is unconstrained, then we reset the type of the
9764 -- result from the type of the expression. For other cases, the actual
9765 -- subtype of the expression is the target type.
9767 if Is_Composite_Type
(Target_Typ
)
9768 and then not Is_Constrained
(Target_Typ
)
9770 Set_Etype
(N
, Etype
(Expr
));
9773 Analyze_Dimension
(N
);
9774 Eval_Qualified_Expression
(N
);
9776 -- If we still have a qualified expression after the static evaluation,
9777 -- then apply a scalar range check if needed. The reason that we do this
9778 -- after the Eval call is that otherwise, the application of the range
9779 -- check may convert an illegal static expression and result in warning
9780 -- rather than giving an error (e.g Integer'(Integer'Last + 1)).
9782 if Nkind
(N
) = N_Qualified_Expression
and then Is_Scalar_Type
(Typ
) then
9783 Apply_Scalar_Range_Check
(Expr
, Typ
);
9786 -- Finally, check whether a predicate applies to the target type. This
9787 -- comes from AI12-0100. As for type conversions, check the enclosing
9788 -- context to prevent an infinite expansion.
9790 if Has_Predicates
(Target_Typ
) then
9791 if Nkind
(Parent
(N
)) = N_Function_Call
9792 and then Present
(Name
(Parent
(N
)))
9793 and then (Is_Predicate_Function
(Entity
(Name
(Parent
(N
))))
9795 Is_Predicate_Function_M
(Entity
(Name
(Parent
(N
)))))
9799 -- In the case of a qualified expression in an allocator, the check
9800 -- is applied when expanding the allocator, so avoid redundant check.
9802 elsif Nkind
(N
) = N_Qualified_Expression
9803 and then Nkind
(Parent
(N
)) /= N_Allocator
9805 Apply_Predicate_Check
(N
, Target_Typ
);
9808 end Resolve_Qualified_Expression
;
9810 ------------------------------
9811 -- Resolve_Raise_Expression --
9812 ------------------------------
9814 procedure Resolve_Raise_Expression
(N
: Node_Id
; Typ
: Entity_Id
) is
9816 if Typ
= Raise_Type
then
9817 Error_Msg_N
("cannot find unique type for raise expression", N
);
9818 Set_Etype
(N
, Any_Type
);
9822 end Resolve_Raise_Expression
;
9828 procedure Resolve_Range
(N
: Node_Id
; Typ
: Entity_Id
) is
9829 L
: constant Node_Id
:= Low_Bound
(N
);
9830 H
: constant Node_Id
:= High_Bound
(N
);
9832 function First_Last_Ref
return Boolean;
9833 -- Returns True if N is of the form X'First .. X'Last where X is the
9834 -- same entity for both attributes.
9836 --------------------
9837 -- First_Last_Ref --
9838 --------------------
9840 function First_Last_Ref
return Boolean is
9841 Lorig
: constant Node_Id
:= Original_Node
(L
);
9842 Horig
: constant Node_Id
:= Original_Node
(H
);
9845 if Nkind
(Lorig
) = N_Attribute_Reference
9846 and then Nkind
(Horig
) = N_Attribute_Reference
9847 and then Attribute_Name
(Lorig
) = Name_First
9848 and then Attribute_Name
(Horig
) = Name_Last
9851 PL
: constant Node_Id
:= Prefix
(Lorig
);
9852 PH
: constant Node_Id
:= Prefix
(Horig
);
9854 if Is_Entity_Name
(PL
)
9855 and then Is_Entity_Name
(PH
)
9856 and then Entity
(PL
) = Entity
(PH
)
9866 -- Start of processing for Resolve_Range
9871 -- The lower bound should be in Typ. The higher bound can be in Typ's
9872 -- base type if the range is null. It may still be invalid if it is
9873 -- higher than the lower bound. This is checked later in the context in
9874 -- which the range appears.
9877 Resolve
(H
, Base_Type
(Typ
));
9879 -- Check for inappropriate range on unordered enumeration type
9881 if Bad_Unordered_Enumeration_Reference
(N
, Typ
)
9883 -- Exclude X'First .. X'Last if X is the same entity for both
9885 and then not First_Last_Ref
9887 Error_Msg_Sloc
:= Sloc
(Typ
);
9889 ("subrange of unordered enumeration type& declared#?U?", N
, Typ
);
9892 Check_Unset_Reference
(L
);
9893 Check_Unset_Reference
(H
);
9895 -- We have to check the bounds for being within the base range as
9896 -- required for a non-static context. Normally this is automatic and
9897 -- done as part of evaluating expressions, but the N_Range node is an
9898 -- exception, since in GNAT we consider this node to be a subexpression,
9899 -- even though in Ada it is not. The circuit in Sem_Eval could check for
9900 -- this, but that would put the test on the main evaluation path for
9903 Check_Non_Static_Context
(L
);
9904 Check_Non_Static_Context
(H
);
9906 -- Check for an ambiguous range over character literals. This will
9907 -- happen with a membership test involving only literals.
9909 if Typ
= Any_Character
then
9910 Ambiguous_Character
(L
);
9911 Set_Etype
(N
, Any_Type
);
9915 -- If bounds are static, constant-fold them, so size computations are
9916 -- identical between front-end and back-end. Do not perform this
9917 -- transformation while analyzing generic units, as type information
9918 -- would be lost when reanalyzing the constant node in the instance.
9920 if Is_Discrete_Type
(Typ
) and then Expander_Active
then
9921 if Is_OK_Static_Expression
(L
) then
9922 Fold_Uint
(L
, Expr_Value
(L
), Is_OK_Static_Expression
(L
));
9925 if Is_OK_Static_Expression
(H
) then
9926 Fold_Uint
(H
, Expr_Value
(H
), Is_OK_Static_Expression
(H
));
9931 --------------------------
9932 -- Resolve_Real_Literal --
9933 --------------------------
9935 procedure Resolve_Real_Literal
(N
: Node_Id
; Typ
: Entity_Id
) is
9936 Actual_Typ
: constant Entity_Id
:= Etype
(N
);
9939 -- Special processing for fixed-point literals to make sure that the
9940 -- value is an exact multiple of small where this is required. We skip
9941 -- this for the universal real case, and also for generic types.
9943 if Is_Fixed_Point_Type
(Typ
)
9944 and then Typ
/= Universal_Fixed
9945 and then Typ
/= Any_Fixed
9946 and then not Is_Generic_Type
(Typ
)
9949 Val
: constant Ureal
:= Realval
(N
);
9950 Cintr
: constant Ureal
:= Val
/ Small_Value
(Typ
);
9951 Cint
: constant Uint
:= UR_Trunc
(Cintr
);
9952 Den
: constant Uint
:= Norm_Den
(Cintr
);
9956 -- Case of literal is not an exact multiple of the Small
9960 -- For a source program literal for a decimal fixed-point type,
9961 -- this is statically illegal (RM 4.9(36)).
9963 if Is_Decimal_Fixed_Point_Type
(Typ
)
9964 and then Actual_Typ
= Universal_Real
9965 and then Comes_From_Source
(N
)
9967 Error_Msg_N
("value has extraneous low order digits", N
);
9970 -- Generate a warning if literal from source
9972 if Is_OK_Static_Expression
(N
)
9973 and then Warn_On_Bad_Fixed_Value
9976 ("?b?static fixed-point value is not a multiple of Small!",
9980 -- Replace literal by a value that is the exact representation
9981 -- of a value of the type, i.e. a multiple of the small value,
9982 -- by truncation, since Machine_Rounds is false for all GNAT
9983 -- fixed-point types (RM 4.9(38)).
9985 Stat
:= Is_OK_Static_Expression
(N
);
9987 Make_Real_Literal
(Sloc
(N
),
9988 Realval
=> Small_Value
(Typ
) * Cint
));
9990 Set_Is_Static_Expression
(N
, Stat
);
9993 -- In all cases, set the corresponding integer field
9995 Set_Corresponding_Integer_Value
(N
, Cint
);
9999 -- Now replace the actual type by the expected type as usual
10001 Set_Etype
(N
, Typ
);
10002 Eval_Real_Literal
(N
);
10003 end Resolve_Real_Literal
;
10005 -----------------------
10006 -- Resolve_Reference --
10007 -----------------------
10009 procedure Resolve_Reference
(N
: Node_Id
; Typ
: Entity_Id
) is
10010 P
: constant Node_Id
:= Prefix
(N
);
10013 -- Replace general access with specific type
10015 if Ekind
(Etype
(N
)) = E_Allocator_Type
then
10016 Set_Etype
(N
, Base_Type
(Typ
));
10019 Resolve
(P
, Designated_Type
(Etype
(N
)));
10021 -- If we are taking the reference of a volatile entity, then treat it as
10022 -- a potential modification of this entity. This is too conservative,
10023 -- but necessary because remove side effects can cause transformations
10024 -- of normal assignments into reference sequences that otherwise fail to
10025 -- notice the modification.
10027 if Is_Entity_Name
(P
) and then Treat_As_Volatile
(Entity
(P
)) then
10028 Note_Possible_Modification
(P
, Sure
=> False);
10030 end Resolve_Reference
;
10032 --------------------------------
10033 -- Resolve_Selected_Component --
10034 --------------------------------
10036 procedure Resolve_Selected_Component
(N
: Node_Id
; Typ
: Entity_Id
) is
10038 Comp1
: Entity_Id
:= Empty
; -- prevent junk warning
10039 P
: constant Node_Id
:= Prefix
(N
);
10040 S
: constant Node_Id
:= Selector_Name
(N
);
10041 T
: Entity_Id
:= Etype
(P
);
10043 I1
: Interp_Index
:= 0; -- prevent junk warning
10048 function Init_Component
return Boolean;
10049 -- Check whether this is the initialization of a component within an
10050 -- init proc (by assignment or call to another init proc). If true,
10051 -- there is no need for a discriminant check.
10053 --------------------
10054 -- Init_Component --
10055 --------------------
10057 function Init_Component
return Boolean is
10059 return Inside_Init_Proc
10060 and then Nkind
(Prefix
(N
)) = N_Identifier
10061 and then Chars
(Prefix
(N
)) = Name_uInit
10062 and then Nkind
(Parent
(Parent
(N
))) = N_Case_Statement_Alternative
;
10063 end Init_Component
;
10065 -- Start of processing for Resolve_Selected_Component
10068 if Is_Overloaded
(P
) then
10070 -- Use the context type to select the prefix that has a selector
10071 -- of the correct name and type.
10074 Get_First_Interp
(P
, I
, It
);
10076 Search
: while Present
(It
.Typ
) loop
10077 if Is_Access_Type
(It
.Typ
) then
10078 T
:= Designated_Type
(It
.Typ
);
10083 -- Locate selected component. For a private prefix the selector
10084 -- can denote a discriminant.
10086 if Is_Record_Type
(T
) or else Is_Private_Type
(T
) then
10088 -- The visible components of a class-wide type are those of
10091 if Is_Class_Wide_Type
(T
) then
10095 Comp
:= First_Entity
(T
);
10096 while Present
(Comp
) loop
10097 if Chars
(Comp
) = Chars
(S
)
10098 and then Covers
(Typ
, Etype
(Comp
))
10107 It
:= Disambiguate
(P
, I1
, I
, Any_Type
);
10109 if It
= No_Interp
then
10111 ("ambiguous prefix for selected component", N
);
10112 Set_Etype
(N
, Typ
);
10118 -- There may be an implicit dereference. Retrieve
10119 -- designated record type.
10121 if Is_Access_Type
(It1
.Typ
) then
10122 T
:= Designated_Type
(It1
.Typ
);
10127 if Scope
(Comp1
) /= T
then
10129 -- Resolution chooses the new interpretation.
10130 -- Find the component with the right name.
10132 Comp1
:= First_Entity
(T
);
10133 while Present
(Comp1
)
10134 and then Chars
(Comp1
) /= Chars
(S
)
10136 Comp1
:= Next_Entity
(Comp1
);
10145 Comp
:= Next_Entity
(Comp
);
10149 Get_Next_Interp
(I
, It
);
10152 -- There must be a legal interpretation at this point
10154 pragma Assert
(Found
);
10155 Resolve
(P
, It1
.Typ
);
10156 Set_Etype
(N
, Typ
);
10157 Set_Entity_With_Checks
(S
, Comp1
);
10160 -- Resolve prefix with its type
10165 -- Generate cross-reference. We needed to wait until full overloading
10166 -- resolution was complete to do this, since otherwise we can't tell if
10167 -- we are an lvalue or not.
10169 if May_Be_Lvalue
(N
) then
10170 Generate_Reference
(Entity
(S
), S
, 'm');
10172 Generate_Reference
(Entity
(S
), S
, 'r');
10175 -- If prefix is an access type, the node will be transformed into an
10176 -- explicit dereference during expansion. The type of the node is the
10177 -- designated type of that of the prefix.
10179 if Is_Access_Type
(Etype
(P
)) then
10180 T
:= Designated_Type
(Etype
(P
));
10181 Check_Fully_Declared_Prefix
(T
, P
);
10186 -- Set flag for expander if discriminant check required on a component
10187 -- appearing within a variant.
10189 if Has_Discriminants
(T
)
10190 and then Ekind
(Entity
(S
)) = E_Component
10191 and then Present
(Original_Record_Component
(Entity
(S
)))
10192 and then Ekind
(Original_Record_Component
(Entity
(S
))) = E_Component
10194 Is_Declared_Within_Variant
(Original_Record_Component
(Entity
(S
)))
10195 and then not Discriminant_Checks_Suppressed
(T
)
10196 and then not Init_Component
10198 Set_Do_Discriminant_Check
(N
);
10201 if Ekind
(Entity
(S
)) = E_Void
then
10202 Error_Msg_N
("premature use of component", S
);
10205 -- If the prefix is a record conversion, this may be a renamed
10206 -- discriminant whose bounds differ from those of the original
10207 -- one, so we must ensure that a range check is performed.
10209 if Nkind
(P
) = N_Type_Conversion
10210 and then Ekind
(Entity
(S
)) = E_Discriminant
10211 and then Is_Discrete_Type
(Typ
)
10213 Set_Etype
(N
, Base_Type
(Typ
));
10216 -- Note: No Eval processing is required, because the prefix is of a
10217 -- record type, or protected type, and neither can possibly be static.
10219 -- If the record type is atomic, and the component is non-atomic, then
10220 -- this is worth a warning, since we have a situation where the access
10221 -- to the component may cause extra read/writes of the atomic array
10222 -- object, or partial word accesses, both of which may be unexpected.
10224 if Nkind
(N
) = N_Selected_Component
10225 and then Is_Atomic_Ref_With_Address
(N
)
10226 and then not Is_Atomic
(Entity
(S
))
10227 and then not Is_Atomic
(Etype
(Entity
(S
)))
10230 ("??access to non-atomic component of atomic record",
10233 ("\??may cause unexpected accesses to atomic object",
10237 Analyze_Dimension
(N
);
10238 end Resolve_Selected_Component
;
10240 -------------------
10241 -- Resolve_Shift --
10242 -------------------
10244 procedure Resolve_Shift
(N
: Node_Id
; Typ
: Entity_Id
) is
10245 B_Typ
: constant Entity_Id
:= Base_Type
(Typ
);
10246 L
: constant Node_Id
:= Left_Opnd
(N
);
10247 R
: constant Node_Id
:= Right_Opnd
(N
);
10250 -- We do the resolution using the base type, because intermediate values
10251 -- in expressions always are of the base type, not a subtype of it.
10253 Resolve
(L
, B_Typ
);
10254 Resolve
(R
, Standard_Natural
);
10256 Check_Unset_Reference
(L
);
10257 Check_Unset_Reference
(R
);
10259 Set_Etype
(N
, B_Typ
);
10260 Generate_Operator_Reference
(N
, B_Typ
);
10264 ---------------------------
10265 -- Resolve_Short_Circuit --
10266 ---------------------------
10268 procedure Resolve_Short_Circuit
(N
: Node_Id
; Typ
: Entity_Id
) is
10269 B_Typ
: constant Entity_Id
:= Base_Type
(Typ
);
10270 L
: constant Node_Id
:= Left_Opnd
(N
);
10271 R
: constant Node_Id
:= Right_Opnd
(N
);
10274 -- Ensure all actions associated with the left operand (e.g.
10275 -- finalization of transient objects) are fully evaluated locally within
10276 -- an expression with actions. This is particularly helpful for coverage
10277 -- analysis. However this should not happen in generics or if option
10278 -- Minimize_Expression_With_Actions is set.
10280 if Expander_Active
and not Minimize_Expression_With_Actions
then
10282 Reloc_L
: constant Node_Id
:= Relocate_Node
(L
);
10284 Save_Interps
(Old_N
=> L
, New_N
=> Reloc_L
);
10287 Make_Expression_With_Actions
(Sloc
(L
),
10288 Actions
=> New_List
,
10289 Expression
=> Reloc_L
));
10291 -- Set Comes_From_Source on L to preserve warnings for unset
10294 Set_Comes_From_Source
(L
, Comes_From_Source
(Reloc_L
));
10298 Resolve
(L
, B_Typ
);
10299 Resolve
(R
, B_Typ
);
10301 -- Check for issuing warning for always False assert/check, this happens
10302 -- when assertions are turned off, in which case the pragma Assert/Check
10303 -- was transformed into:
10305 -- if False and then <condition> then ...
10307 -- and we detect this pattern
10309 if Warn_On_Assertion_Failure
10310 and then Is_Entity_Name
(R
)
10311 and then Entity
(R
) = Standard_False
10312 and then Nkind
(Parent
(N
)) = N_If_Statement
10313 and then Nkind
(N
) = N_And_Then
10314 and then Is_Entity_Name
(L
)
10315 and then Entity
(L
) = Standard_False
10318 Orig
: constant Node_Id
:= Original_Node
(Parent
(N
));
10321 -- Special handling of Asssert pragma
10323 if Nkind
(Orig
) = N_Pragma
10324 and then Pragma_Name
(Orig
) = Name_Assert
10327 Expr
: constant Node_Id
:=
10330 (First
(Pragma_Argument_Associations
(Orig
))));
10333 -- Don't warn if original condition is explicit False,
10334 -- since obviously the failure is expected in this case.
10336 if Is_Entity_Name
(Expr
)
10337 and then Entity
(Expr
) = Standard_False
10341 -- Issue warning. We do not want the deletion of the
10342 -- IF/AND-THEN to take this message with it. We achieve this
10343 -- by making sure that the expanded code points to the Sloc
10344 -- of the expression, not the original pragma.
10347 -- Note: Use Error_Msg_F here rather than Error_Msg_N.
10348 -- The source location of the expression is not usually
10349 -- the best choice here. For example, it gets located on
10350 -- the last AND keyword in a chain of boolean expressiond
10351 -- AND'ed together. It is best to put the message on the
10352 -- first character of the assertion, which is the effect
10353 -- of the First_Node call here.
10356 ("?A?assertion would fail at run time!",
10358 (First
(Pragma_Argument_Associations
(Orig
))));
10362 -- Similar processing for Check pragma
10364 elsif Nkind
(Orig
) = N_Pragma
10365 and then Pragma_Name
(Orig
) = Name_Check
10367 -- Don't want to warn if original condition is explicit False
10370 Expr
: constant Node_Id
:=
10373 (Next
(First
(Pragma_Argument_Associations
(Orig
)))));
10375 if Is_Entity_Name
(Expr
)
10376 and then Entity
(Expr
) = Standard_False
10383 -- Again use Error_Msg_F rather than Error_Msg_N, see
10384 -- comment above for an explanation of why we do this.
10387 ("?A?check would fail at run time!",
10389 (Last
(Pragma_Argument_Associations
(Orig
))));
10396 -- Continue with processing of short circuit
10398 Check_Unset_Reference
(L
);
10399 Check_Unset_Reference
(R
);
10401 Set_Etype
(N
, B_Typ
);
10402 Eval_Short_Circuit
(N
);
10403 end Resolve_Short_Circuit
;
10405 -------------------
10406 -- Resolve_Slice --
10407 -------------------
10409 procedure Resolve_Slice
(N
: Node_Id
; Typ
: Entity_Id
) is
10410 Drange
: constant Node_Id
:= Discrete_Range
(N
);
10411 Name
: constant Node_Id
:= Prefix
(N
);
10412 Array_Type
: Entity_Id
:= Empty
;
10413 Dexpr
: Node_Id
:= Empty
;
10414 Index_Type
: Entity_Id
;
10417 if Is_Overloaded
(Name
) then
10419 -- Use the context type to select the prefix that yields the correct
10424 I1
: Interp_Index
:= 0;
10426 P
: constant Node_Id
:= Prefix
(N
);
10427 Found
: Boolean := False;
10430 Get_First_Interp
(P
, I
, It
);
10431 while Present
(It
.Typ
) loop
10432 if (Is_Array_Type
(It
.Typ
)
10433 and then Covers
(Typ
, It
.Typ
))
10434 or else (Is_Access_Type
(It
.Typ
)
10435 and then Is_Array_Type
(Designated_Type
(It
.Typ
))
10436 and then Covers
(Typ
, Designated_Type
(It
.Typ
)))
10439 It
:= Disambiguate
(P
, I1
, I
, Any_Type
);
10441 if It
= No_Interp
then
10442 Error_Msg_N
("ambiguous prefix for slicing", N
);
10443 Set_Etype
(N
, Typ
);
10447 Array_Type
:= It
.Typ
;
10452 Array_Type
:= It
.Typ
;
10457 Get_Next_Interp
(I
, It
);
10462 Array_Type
:= Etype
(Name
);
10465 Resolve
(Name
, Array_Type
);
10467 if Is_Access_Type
(Array_Type
) then
10468 Apply_Access_Check
(N
);
10469 Array_Type
:= Designated_Type
(Array_Type
);
10471 -- If the prefix is an access to an unconstrained array, we must use
10472 -- the actual subtype of the object to perform the index checks. The
10473 -- object denoted by the prefix is implicit in the node, so we build
10474 -- an explicit representation for it in order to compute the actual
10477 if not Is_Constrained
(Array_Type
) then
10478 Remove_Side_Effects
(Prefix
(N
));
10481 Obj
: constant Node_Id
:=
10482 Make_Explicit_Dereference
(Sloc
(N
),
10483 Prefix
=> New_Copy_Tree
(Prefix
(N
)));
10485 Set_Etype
(Obj
, Array_Type
);
10486 Set_Parent
(Obj
, Parent
(N
));
10487 Array_Type
:= Get_Actual_Subtype
(Obj
);
10491 elsif Is_Entity_Name
(Name
)
10492 or else Nkind
(Name
) = N_Explicit_Dereference
10493 or else (Nkind
(Name
) = N_Function_Call
10494 and then not Is_Constrained
(Etype
(Name
)))
10496 Array_Type
:= Get_Actual_Subtype
(Name
);
10498 -- If the name is a selected component that depends on discriminants,
10499 -- build an actual subtype for it. This can happen only when the name
10500 -- itself is overloaded; otherwise the actual subtype is created when
10501 -- the selected component is analyzed.
10503 elsif Nkind
(Name
) = N_Selected_Component
10504 and then Full_Analysis
10505 and then Depends_On_Discriminant
(First_Index
(Array_Type
))
10508 Act_Decl
: constant Node_Id
:=
10509 Build_Actual_Subtype_Of_Component
(Array_Type
, Name
);
10511 Insert_Action
(N
, Act_Decl
);
10512 Array_Type
:= Defining_Identifier
(Act_Decl
);
10515 -- Maybe this should just be "else", instead of checking for the
10516 -- specific case of slice??? This is needed for the case where the
10517 -- prefix is an Image attribute, which gets expanded to a slice, and so
10518 -- has a constrained subtype which we want to use for the slice range
10519 -- check applied below (the range check won't get done if the
10520 -- unconstrained subtype of the 'Image is used).
10522 elsif Nkind
(Name
) = N_Slice
then
10523 Array_Type
:= Etype
(Name
);
10526 -- Obtain the type of the array index
10528 if Ekind
(Array_Type
) = E_String_Literal_Subtype
then
10529 Index_Type
:= Etype
(String_Literal_Low_Bound
(Array_Type
));
10531 Index_Type
:= Etype
(First_Index
(Array_Type
));
10534 -- If name was overloaded, set slice type correctly now
10536 Set_Etype
(N
, Array_Type
);
10538 -- Handle the generation of a range check that compares the array index
10539 -- against the discrete_range. The check is not applied to internally
10540 -- built nodes associated with the expansion of dispatch tables. Check
10541 -- that Ada.Tags has already been loaded to avoid extra dependencies on
10544 if Tagged_Type_Expansion
10545 and then RTU_Loaded
(Ada_Tags
)
10546 and then Nkind
(Prefix
(N
)) = N_Selected_Component
10547 and then Present
(Entity
(Selector_Name
(Prefix
(N
))))
10548 and then Entity
(Selector_Name
(Prefix
(N
))) =
10549 RTE_Record_Component
(RE_Prims_Ptr
)
10553 -- The discrete_range is specified by a subtype indication. Create a
10554 -- shallow copy and inherit the type, parent and source location from
10555 -- the discrete_range. This ensures that the range check is inserted
10556 -- relative to the slice and that the runtime exception points to the
10557 -- proper construct.
10559 elsif Is_Entity_Name
(Drange
) then
10560 Dexpr
:= New_Copy
(Scalar_Range
(Entity
(Drange
)));
10562 Set_Etype
(Dexpr
, Etype
(Drange
));
10563 Set_Parent
(Dexpr
, Parent
(Drange
));
10564 Set_Sloc
(Dexpr
, Sloc
(Drange
));
10566 -- The discrete_range is a regular range. Resolve the bounds and remove
10567 -- their side effects.
10570 Resolve
(Drange
, Base_Type
(Index_Type
));
10572 if Nkind
(Drange
) = N_Range
then
10573 Force_Evaluation
(Low_Bound
(Drange
));
10574 Force_Evaluation
(High_Bound
(Drange
));
10580 if Present
(Dexpr
) then
10581 Apply_Range_Check
(Dexpr
, Index_Type
);
10584 Set_Slice_Subtype
(N
);
10586 -- Check bad use of type with predicates
10592 if Nkind
(Drange
) = N_Subtype_Indication
10593 and then Has_Predicates
(Entity
(Subtype_Mark
(Drange
)))
10595 Subt
:= Entity
(Subtype_Mark
(Drange
));
10597 Subt
:= Etype
(Drange
);
10600 if Has_Predicates
(Subt
) then
10601 Bad_Predicated_Subtype_Use
10602 ("subtype& has predicate, not allowed in slice", Drange
, Subt
);
10606 -- Otherwise here is where we check suspicious indexes
10608 if Nkind
(Drange
) = N_Range
then
10609 Warn_On_Suspicious_Index
(Name
, Low_Bound
(Drange
));
10610 Warn_On_Suspicious_Index
(Name
, High_Bound
(Drange
));
10613 Analyze_Dimension
(N
);
10617 ----------------------------
10618 -- Resolve_String_Literal --
10619 ----------------------------
10621 procedure Resolve_String_Literal
(N
: Node_Id
; Typ
: Entity_Id
) is
10622 C_Typ
: constant Entity_Id
:= Component_Type
(Typ
);
10623 R_Typ
: constant Entity_Id
:= Root_Type
(C_Typ
);
10624 Loc
: constant Source_Ptr
:= Sloc
(N
);
10625 Str
: constant String_Id
:= Strval
(N
);
10626 Strlen
: constant Nat
:= String_Length
(Str
);
10627 Subtype_Id
: Entity_Id
;
10628 Need_Check
: Boolean;
10631 -- For a string appearing in a concatenation, defer creation of the
10632 -- string_literal_subtype until the end of the resolution of the
10633 -- concatenation, because the literal may be constant-folded away. This
10634 -- is a useful optimization for long concatenation expressions.
10636 -- If the string is an aggregate built for a single character (which
10637 -- happens in a non-static context) or a is null string to which special
10638 -- checks may apply, we build the subtype. Wide strings must also get a
10639 -- string subtype if they come from a one character aggregate. Strings
10640 -- generated by attributes might be static, but it is often hard to
10641 -- determine whether the enclosing context is static, so we generate
10642 -- subtypes for them as well, thus losing some rarer optimizations ???
10643 -- Same for strings that come from a static conversion.
10646 (Strlen
= 0 and then Typ
/= Standard_String
)
10647 or else Nkind
(Parent
(N
)) /= N_Op_Concat
10648 or else (N
/= Left_Opnd
(Parent
(N
))
10649 and then N
/= Right_Opnd
(Parent
(N
)))
10650 or else ((Typ
= Standard_Wide_String
10651 or else Typ
= Standard_Wide_Wide_String
)
10652 and then Nkind
(Original_Node
(N
)) /= N_String_Literal
);
10654 -- If the resolving type is itself a string literal subtype, we can just
10655 -- reuse it, since there is no point in creating another.
10657 if Ekind
(Typ
) = E_String_Literal_Subtype
then
10660 elsif Nkind
(Parent
(N
)) = N_Op_Concat
10661 and then not Need_Check
10662 and then not Nkind_In
(Original_Node
(N
), N_Character_Literal
,
10663 N_Attribute_Reference
,
10664 N_Qualified_Expression
,
10669 -- Do not generate a string literal subtype for the default expression
10670 -- of a formal parameter in GNATprove mode. This is because the string
10671 -- subtype is associated with the freezing actions of the subprogram,
10672 -- however freezing is disabled in GNATprove mode and as a result the
10673 -- subtype is unavailable.
10675 elsif GNATprove_Mode
10676 and then Nkind
(Parent
(N
)) = N_Parameter_Specification
10680 -- Otherwise we must create a string literal subtype. Note that the
10681 -- whole idea of string literal subtypes is simply to avoid the need
10682 -- for building a full fledged array subtype for each literal.
10685 Set_String_Literal_Subtype
(N
, Typ
);
10686 Subtype_Id
:= Etype
(N
);
10689 if Nkind
(Parent
(N
)) /= N_Op_Concat
10692 Set_Etype
(N
, Subtype_Id
);
10693 Eval_String_Literal
(N
);
10696 if Is_Limited_Composite
(Typ
)
10697 or else Is_Private_Composite
(Typ
)
10699 Error_Msg_N
("string literal not available for private array", N
);
10700 Set_Etype
(N
, Any_Type
);
10704 -- The validity of a null string has been checked in the call to
10705 -- Eval_String_Literal.
10710 -- Always accept string literal with component type Any_Character, which
10711 -- occurs in error situations and in comparisons of literals, both of
10712 -- which should accept all literals.
10714 elsif R_Typ
= Any_Character
then
10717 -- If the type is bit-packed, then we always transform the string
10718 -- literal into a full fledged aggregate.
10720 elsif Is_Bit_Packed_Array
(Typ
) then
10723 -- Deal with cases of Wide_Wide_String, Wide_String, and String
10726 -- For Standard.Wide_Wide_String, or any other type whose component
10727 -- type is Standard.Wide_Wide_Character, we know that all the
10728 -- characters in the string must be acceptable, since the parser
10729 -- accepted the characters as valid character literals.
10731 if R_Typ
= Standard_Wide_Wide_Character
then
10734 -- For the case of Standard.String, or any other type whose component
10735 -- type is Standard.Character, we must make sure that there are no
10736 -- wide characters in the string, i.e. that it is entirely composed
10737 -- of characters in range of type Character.
10739 -- If the string literal is the result of a static concatenation, the
10740 -- test has already been performed on the components, and need not be
10743 elsif R_Typ
= Standard_Character
10744 and then Nkind
(Original_Node
(N
)) /= N_Op_Concat
10746 for J
in 1 .. Strlen
loop
10747 if not In_Character_Range
(Get_String_Char
(Str
, J
)) then
10749 -- If we are out of range, post error. This is one of the
10750 -- very few places that we place the flag in the middle of
10751 -- a token, right under the offending wide character. Not
10752 -- quite clear if this is right wrt wide character encoding
10753 -- sequences, but it's only an error message.
10756 ("literal out of range of type Standard.Character",
10757 Source_Ptr
(Int
(Loc
) + J
));
10762 -- For the case of Standard.Wide_String, or any other type whose
10763 -- component type is Standard.Wide_Character, we must make sure that
10764 -- there are no wide characters in the string, i.e. that it is
10765 -- entirely composed of characters in range of type Wide_Character.
10767 -- If the string literal is the result of a static concatenation,
10768 -- the test has already been performed on the components, and need
10769 -- not be repeated.
10771 elsif R_Typ
= Standard_Wide_Character
10772 and then Nkind
(Original_Node
(N
)) /= N_Op_Concat
10774 for J
in 1 .. Strlen
loop
10775 if not In_Wide_Character_Range
(Get_String_Char
(Str
, J
)) then
10777 -- If we are out of range, post error. This is one of the
10778 -- very few places that we place the flag in the middle of
10779 -- a token, right under the offending wide character.
10781 -- This is not quite right, because characters in general
10782 -- will take more than one character position ???
10785 ("literal out of range of type Standard.Wide_Character",
10786 Source_Ptr
(Int
(Loc
) + J
));
10791 -- If the root type is not a standard character, then we will convert
10792 -- the string into an aggregate and will let the aggregate code do
10793 -- the checking. Standard Wide_Wide_Character is also OK here.
10799 -- See if the component type of the array corresponding to the string
10800 -- has compile time known bounds. If yes we can directly check
10801 -- whether the evaluation of the string will raise constraint error.
10802 -- Otherwise we need to transform the string literal into the
10803 -- corresponding character aggregate and let the aggregate code do
10806 if Is_Standard_Character_Type
(R_Typ
) then
10808 -- Check for the case of full range, where we are definitely OK
10810 if Component_Type
(Typ
) = Base_Type
(Component_Type
(Typ
)) then
10814 -- Here the range is not the complete base type range, so check
10817 Comp_Typ_Lo
: constant Node_Id
:=
10818 Type_Low_Bound
(Component_Type
(Typ
));
10819 Comp_Typ_Hi
: constant Node_Id
:=
10820 Type_High_Bound
(Component_Type
(Typ
));
10825 if Compile_Time_Known_Value
(Comp_Typ_Lo
)
10826 and then Compile_Time_Known_Value
(Comp_Typ_Hi
)
10828 for J
in 1 .. Strlen
loop
10829 Char_Val
:= UI_From_Int
(Int
(Get_String_Char
(Str
, J
)));
10831 if Char_Val
< Expr_Value
(Comp_Typ_Lo
)
10832 or else Char_Val
> Expr_Value
(Comp_Typ_Hi
)
10834 Apply_Compile_Time_Constraint_Error
10835 (N
, "character out of range??",
10836 CE_Range_Check_Failed
,
10837 Loc
=> Source_Ptr
(Int
(Loc
) + J
));
10847 -- If we got here we meed to transform the string literal into the
10848 -- equivalent qualified positional array aggregate. This is rather
10849 -- heavy artillery for this situation, but it is hard work to avoid.
10852 Lits
: constant List_Id
:= New_List
;
10853 P
: Source_Ptr
:= Loc
+ 1;
10857 -- Build the character literals, we give them source locations that
10858 -- correspond to the string positions, which is a bit tricky given
10859 -- the possible presence of wide character escape sequences.
10861 for J
in 1 .. Strlen
loop
10862 C
:= Get_String_Char
(Str
, J
);
10863 Set_Character_Literal_Name
(C
);
10866 Make_Character_Literal
(P
,
10867 Chars
=> Name_Find
,
10868 Char_Literal_Value
=> UI_From_CC
(C
)));
10870 if In_Character_Range
(C
) then
10873 -- Should we have a call to Skip_Wide here ???
10882 Make_Qualified_Expression
(Loc
,
10883 Subtype_Mark
=> New_Occurrence_Of
(Typ
, Loc
),
10885 Make_Aggregate
(Loc
, Expressions
=> Lits
)));
10887 Analyze_And_Resolve
(N
, Typ
);
10889 end Resolve_String_Literal
;
10891 -------------------------
10892 -- Resolve_Target_Name --
10893 -------------------------
10895 procedure Resolve_Target_Name
(N
: Node_Id
; Typ
: Entity_Id
) is
10897 Set_Etype
(N
, Typ
);
10898 end Resolve_Target_Name
;
10900 -----------------------------
10901 -- Resolve_Type_Conversion --
10902 -----------------------------
10904 procedure Resolve_Type_Conversion
(N
: Node_Id
; Typ
: Entity_Id
) is
10905 Conv_OK
: constant Boolean := Conversion_OK
(N
);
10906 Operand
: constant Node_Id
:= Expression
(N
);
10907 Operand_Typ
: constant Entity_Id
:= Etype
(Operand
);
10908 Target_Typ
: constant Entity_Id
:= Etype
(N
);
10913 Test_Redundant
: Boolean := Warn_On_Redundant_Constructs
;
10914 -- Set to False to suppress cases where we want to suppress the test
10915 -- for redundancy to avoid possible false positives on this warning.
10919 and then not Valid_Conversion
(N
, Target_Typ
, Operand
)
10924 -- If the Operand Etype is Universal_Fixed, then the conversion is
10925 -- never redundant. We need this check because by the time we have
10926 -- finished the rather complex transformation, the conversion looks
10927 -- redundant when it is not.
10929 if Operand_Typ
= Universal_Fixed
then
10930 Test_Redundant
:= False;
10932 -- If the operand is marked as Any_Fixed, then special processing is
10933 -- required. This is also a case where we suppress the test for a
10934 -- redundant conversion, since most certainly it is not redundant.
10936 elsif Operand_Typ
= Any_Fixed
then
10937 Test_Redundant
:= False;
10939 -- Mixed-mode operation involving a literal. Context must be a fixed
10940 -- type which is applied to the literal subsequently.
10942 -- Multiplication and division involving two fixed type operands must
10943 -- yield a universal real because the result is computed in arbitrary
10946 if Is_Fixed_Point_Type
(Typ
)
10947 and then Nkind_In
(Operand
, N_Op_Divide
, N_Op_Multiply
)
10948 and then Etype
(Left_Opnd
(Operand
)) = Any_Fixed
10949 and then Etype
(Right_Opnd
(Operand
)) = Any_Fixed
10951 Set_Etype
(Operand
, Universal_Real
);
10953 elsif Is_Numeric_Type
(Typ
)
10954 and then Nkind_In
(Operand
, N_Op_Multiply
, N_Op_Divide
)
10955 and then (Etype
(Right_Opnd
(Operand
)) = Universal_Real
10957 Etype
(Left_Opnd
(Operand
)) = Universal_Real
)
10959 -- Return if expression is ambiguous
10961 if Unique_Fixed_Point_Type
(N
) = Any_Type
then
10964 -- If nothing else, the available fixed type is Duration
10967 Set_Etype
(Operand
, Standard_Duration
);
10970 -- Resolve the real operand with largest available precision
10972 if Etype
(Right_Opnd
(Operand
)) = Universal_Real
then
10973 Rop
:= New_Copy_Tree
(Right_Opnd
(Operand
));
10975 Rop
:= New_Copy_Tree
(Left_Opnd
(Operand
));
10978 Resolve
(Rop
, Universal_Real
);
10980 -- If the operand is a literal (it could be a non-static and
10981 -- illegal exponentiation) check whether the use of Duration
10982 -- is potentially inaccurate.
10984 if Nkind
(Rop
) = N_Real_Literal
10985 and then Realval
(Rop
) /= Ureal_0
10986 and then abs (Realval
(Rop
)) < Delta_Value
(Standard_Duration
)
10989 ("??universal real operand can only "
10990 & "be interpreted as Duration!", Rop
);
10992 ("\??precision will be lost in the conversion!", Rop
);
10995 elsif Is_Numeric_Type
(Typ
)
10996 and then Nkind
(Operand
) in N_Op
10997 and then Unique_Fixed_Point_Type
(N
) /= Any_Type
10999 Set_Etype
(Operand
, Standard_Duration
);
11002 Error_Msg_N
("invalid context for mixed mode operation", N
);
11003 Set_Etype
(Operand
, Any_Type
);
11010 -- In SPARK, a type conversion between array types should be restricted
11011 -- to types which have matching static bounds.
11013 -- Protect call to Matching_Static_Array_Bounds to avoid costly
11014 -- operation if not needed.
11016 if Restriction_Check_Required
(SPARK_05
)
11017 and then Is_Array_Type
(Target_Typ
)
11018 and then Is_Array_Type
(Operand_Typ
)
11019 and then Operand_Typ
/= Any_Composite
-- or else Operand in error
11020 and then not Matching_Static_Array_Bounds
(Target_Typ
, Operand_Typ
)
11022 Check_SPARK_05_Restriction
11023 ("array types should have matching static bounds", N
);
11026 -- In formal mode, the operand of an ancestor type conversion must be an
11027 -- object (not an expression).
11029 if Is_Tagged_Type
(Target_Typ
)
11030 and then not Is_Class_Wide_Type
(Target_Typ
)
11031 and then Is_Tagged_Type
(Operand_Typ
)
11032 and then not Is_Class_Wide_Type
(Operand_Typ
)
11033 and then Is_Ancestor
(Target_Typ
, Operand_Typ
)
11034 and then not Is_SPARK_05_Object_Reference
(Operand
)
11036 Check_SPARK_05_Restriction
("object required", Operand
);
11039 Analyze_Dimension
(N
);
11041 -- Note: we do the Eval_Type_Conversion call before applying the
11042 -- required checks for a subtype conversion. This is important, since
11043 -- both are prepared under certain circumstances to change the type
11044 -- conversion to a constraint error node, but in the case of
11045 -- Eval_Type_Conversion this may reflect an illegality in the static
11046 -- case, and we would miss the illegality (getting only a warning
11047 -- message), if we applied the type conversion checks first.
11049 Eval_Type_Conversion
(N
);
11051 -- Even when evaluation is not possible, we may be able to simplify the
11052 -- conversion or its expression. This needs to be done before applying
11053 -- checks, since otherwise the checks may use the original expression
11054 -- and defeat the simplifications. This is specifically the case for
11055 -- elimination of the floating-point Truncation attribute in
11056 -- float-to-int conversions.
11058 Simplify_Type_Conversion
(N
);
11060 -- If after evaluation we still have a type conversion, then we may need
11061 -- to apply checks required for a subtype conversion.
11063 -- Skip these type conversion checks if universal fixed operands
11064 -- operands involved, since range checks are handled separately for
11065 -- these cases (in the appropriate Expand routines in unit Exp_Fixd).
11067 if Nkind
(N
) = N_Type_Conversion
11068 and then not Is_Generic_Type
(Root_Type
(Target_Typ
))
11069 and then Target_Typ
/= Universal_Fixed
11070 and then Operand_Typ
/= Universal_Fixed
11072 Apply_Type_Conversion_Checks
(N
);
11075 -- Issue warning for conversion of simple object to its own type. We
11076 -- have to test the original nodes, since they may have been rewritten
11077 -- by various optimizations.
11079 Orig_N
:= Original_Node
(N
);
11081 -- Here we test for a redundant conversion if the warning mode is
11082 -- active (and was not locally reset), and we have a type conversion
11083 -- from source not appearing in a generic instance.
11086 and then Nkind
(Orig_N
) = N_Type_Conversion
11087 and then Comes_From_Source
(Orig_N
)
11088 and then not In_Instance
11090 Orig_N
:= Original_Node
(Expression
(Orig_N
));
11091 Orig_T
:= Target_Typ
;
11093 -- If the node is part of a larger expression, the Target_Type
11094 -- may not be the original type of the node if the context is a
11095 -- condition. Recover original type to see if conversion is needed.
11097 if Is_Boolean_Type
(Orig_T
)
11098 and then Nkind
(Parent
(N
)) in N_Op
11100 Orig_T
:= Etype
(Parent
(N
));
11103 -- If we have an entity name, then give the warning if the entity
11104 -- is the right type, or if it is a loop parameter covered by the
11105 -- original type (that's needed because loop parameters have an
11106 -- odd subtype coming from the bounds).
11108 if (Is_Entity_Name
(Orig_N
)
11110 (Etype
(Entity
(Orig_N
)) = Orig_T
11112 (Ekind
(Entity
(Orig_N
)) = E_Loop_Parameter
11113 and then Covers
(Orig_T
, Etype
(Entity
(Orig_N
))))))
11115 -- If not an entity, then type of expression must match
11117 or else Etype
(Orig_N
) = Orig_T
11119 -- One more check, do not give warning if the analyzed conversion
11120 -- has an expression with non-static bounds, and the bounds of the
11121 -- target are static. This avoids junk warnings in cases where the
11122 -- conversion is necessary to establish staticness, for example in
11123 -- a case statement.
11125 if not Is_OK_Static_Subtype
(Operand_Typ
)
11126 and then Is_OK_Static_Subtype
(Target_Typ
)
11130 -- Finally, if this type conversion occurs in a context requiring
11131 -- a prefix, and the expression is a qualified expression then the
11132 -- type conversion is not redundant, since a qualified expression
11133 -- is not a prefix, whereas a type conversion is. For example, "X
11134 -- := T'(Funx(...)).Y;" is illegal because a selected component
11135 -- requires a prefix, but a type conversion makes it legal: "X :=
11136 -- T(T'(Funx(...))).Y;"
11138 -- In Ada 2012, a qualified expression is a name, so this idiom is
11139 -- no longer needed, but we still suppress the warning because it
11140 -- seems unfriendly for warnings to pop up when you switch to the
11141 -- newer language version.
11143 elsif Nkind
(Orig_N
) = N_Qualified_Expression
11144 and then Nkind_In
(Parent
(N
), N_Attribute_Reference
,
11145 N_Indexed_Component
,
11146 N_Selected_Component
,
11148 N_Explicit_Dereference
)
11152 -- Never warn on conversion to Long_Long_Integer'Base since
11153 -- that is most likely an artifact of the extended overflow
11154 -- checking and comes from complex expanded code.
11156 elsif Orig_T
= Base_Type
(Standard_Long_Long_Integer
) then
11159 -- Here we give the redundant conversion warning. If it is an
11160 -- entity, give the name of the entity in the message. If not,
11161 -- just mention the expression.
11163 -- Shoudn't we test Warn_On_Redundant_Constructs here ???
11166 if Is_Entity_Name
(Orig_N
) then
11167 Error_Msg_Node_2
:= Orig_T
;
11168 Error_Msg_NE
-- CODEFIX
11169 ("??redundant conversion, & is of type &!",
11170 N
, Entity
(Orig_N
));
11173 ("??redundant conversion, expression is of type&!",
11180 -- Ada 2005 (AI-251): Handle class-wide interface type conversions.
11181 -- No need to perform any interface conversion if the type of the
11182 -- expression coincides with the target type.
11184 if Ada_Version
>= Ada_2005
11185 and then Expander_Active
11186 and then Operand_Typ
/= Target_Typ
11189 Opnd
: Entity_Id
:= Operand_Typ
;
11190 Target
: Entity_Id
:= Target_Typ
;
11193 -- If the type of the operand is a limited view, use nonlimited
11194 -- view when available. If it is a class-wide type, recover the
11195 -- class-wide type of the nonlimited view.
11197 if From_Limited_With
(Opnd
)
11198 and then Has_Non_Limited_View
(Opnd
)
11200 Opnd
:= Non_Limited_View
(Opnd
);
11201 Set_Etype
(Expression
(N
), Opnd
);
11204 if Is_Access_Type
(Opnd
) then
11205 Opnd
:= Designated_Type
(Opnd
);
11208 if Is_Access_Type
(Target_Typ
) then
11209 Target
:= Designated_Type
(Target
);
11212 if Opnd
= Target
then
11215 -- Conversion from interface type
11217 elsif Is_Interface
(Opnd
) then
11219 -- Ada 2005 (AI-217): Handle entities from limited views
11221 if From_Limited_With
(Opnd
) then
11222 Error_Msg_Qual_Level
:= 99;
11223 Error_Msg_NE
-- CODEFIX
11224 ("missing WITH clause on package &", N
,
11225 Cunit_Entity
(Get_Source_Unit
(Base_Type
(Opnd
))));
11227 ("type conversions require visibility of the full view",
11230 elsif From_Limited_With
(Target
)
11232 (Is_Access_Type
(Target_Typ
)
11233 and then Present
(Non_Limited_View
(Etype
(Target
))))
11235 Error_Msg_Qual_Level
:= 99;
11236 Error_Msg_NE
-- CODEFIX
11237 ("missing WITH clause on package &", N
,
11238 Cunit_Entity
(Get_Source_Unit
(Base_Type
(Target
))));
11240 ("type conversions require visibility of the full view",
11244 Expand_Interface_Conversion
(N
);
11247 -- Conversion to interface type
11249 elsif Is_Interface
(Target
) then
11253 if Ekind_In
(Opnd
, E_Protected_Subtype
, E_Task_Subtype
) then
11254 Opnd
:= Etype
(Opnd
);
11257 if Is_Class_Wide_Type
(Opnd
)
11258 or else Interface_Present_In_Ancestor
11262 Expand_Interface_Conversion
(N
);
11264 Error_Msg_Name_1
:= Chars
(Etype
(Target
));
11265 Error_Msg_Name_2
:= Chars
(Opnd
);
11267 ("wrong interface conversion (% is not a progenitor "
11274 -- Ada 2012: once the type conversion is resolved, check whether the
11275 -- operand statisfies the static predicate of the target type.
11277 if Has_Predicates
(Target_Typ
) then
11278 Check_Expression_Against_Static_Predicate
(N
, Target_Typ
);
11281 -- If at this stage we have a real to integer conversion, make sure that
11282 -- the Do_Range_Check flag is set, because such conversions in general
11283 -- need a range check. We only need this if expansion is off.
11284 -- In GNATprove mode, we only do that when converting from fixed-point
11285 -- (as floating-point to integer conversions are now handled in
11286 -- GNATprove mode).
11288 if Nkind
(N
) = N_Type_Conversion
11289 and then not Expander_Active
11290 and then Is_Integer_Type
(Target_Typ
)
11291 and then (Is_Fixed_Point_Type
(Operand_Typ
)
11292 or else (not GNATprove_Mode
11293 and then Is_Floating_Point_Type
(Operand_Typ
)))
11295 Set_Do_Range_Check
(Operand
);
11298 -- Generating C code a type conversion of an access to constrained
11299 -- array type to access to unconstrained array type involves building
11300 -- a fat pointer which in general cannot be generated on the fly. We
11301 -- remove side effects in order to store the result of the conversion
11302 -- into a temporary.
11304 if Modify_Tree_For_C
11305 and then Nkind
(N
) = N_Type_Conversion
11306 and then Nkind
(Parent
(N
)) /= N_Object_Declaration
11307 and then Is_Access_Type
(Etype
(N
))
11308 and then Is_Array_Type
(Designated_Type
(Etype
(N
)))
11309 and then not Is_Constrained
(Designated_Type
(Etype
(N
)))
11310 and then Is_Constrained
(Designated_Type
(Etype
(Expression
(N
))))
11312 Remove_Side_Effects
(N
);
11314 end Resolve_Type_Conversion
;
11316 ----------------------
11317 -- Resolve_Unary_Op --
11318 ----------------------
11320 procedure Resolve_Unary_Op
(N
: Node_Id
; Typ
: Entity_Id
) is
11321 B_Typ
: constant Entity_Id
:= Base_Type
(Typ
);
11322 R
: constant Node_Id
:= Right_Opnd
(N
);
11328 if Is_Modular_Integer_Type
(Typ
) and then Nkind
(N
) /= N_Op_Not
then
11329 Error_Msg_Name_1
:= Chars
(Typ
);
11330 Check_SPARK_05_Restriction
11331 ("unary operator not defined for modular type%", N
);
11334 -- Deal with intrinsic unary operators
11336 if Comes_From_Source
(N
)
11337 and then Ekind
(Entity
(N
)) = E_Function
11338 and then Is_Imported
(Entity
(N
))
11339 and then Is_Intrinsic_Subprogram
(Entity
(N
))
11341 Resolve_Intrinsic_Unary_Operator
(N
, Typ
);
11345 -- Deal with universal cases
11347 if Etype
(R
) = Universal_Integer
11349 Etype
(R
) = Universal_Real
11351 Check_For_Visible_Operator
(N
, B_Typ
);
11354 Set_Etype
(N
, B_Typ
);
11355 Resolve
(R
, B_Typ
);
11357 -- Generate warning for expressions like abs (x mod 2)
11359 if Warn_On_Redundant_Constructs
11360 and then Nkind
(N
) = N_Op_Abs
11362 Determine_Range
(Right_Opnd
(N
), OK
, Lo
, Hi
);
11364 if OK
and then Hi
>= Lo
and then Lo
>= 0 then
11365 Error_Msg_N
-- CODEFIX
11366 ("?r?abs applied to known non-negative value has no effect", N
);
11370 -- Deal with reference generation
11372 Check_Unset_Reference
(R
);
11373 Generate_Operator_Reference
(N
, B_Typ
);
11374 Analyze_Dimension
(N
);
11377 -- Set overflow checking bit. Much cleverer code needed here eventually
11378 -- and perhaps the Resolve routines should be separated for the various
11379 -- arithmetic operations, since they will need different processing ???
11381 if Nkind
(N
) in N_Op
then
11382 if not Overflow_Checks_Suppressed
(Etype
(N
)) then
11383 Enable_Overflow_Check
(N
);
11387 -- Generate warning for expressions like -5 mod 3 for integers. No need
11388 -- to worry in the floating-point case, since parens do not affect the
11389 -- result so there is no point in giving in a warning.
11392 Norig
: constant Node_Id
:= Original_Node
(N
);
11401 if Warn_On_Questionable_Missing_Parens
11402 and then Comes_From_Source
(Norig
)
11403 and then Is_Integer_Type
(Typ
)
11404 and then Nkind
(Norig
) = N_Op_Minus
11406 Rorig
:= Original_Node
(Right_Opnd
(Norig
));
11408 -- We are looking for cases where the right operand is not
11409 -- parenthesized, and is a binary operator, multiply, divide, or
11410 -- mod. These are the cases where the grouping can affect results.
11412 if Paren_Count
(Rorig
) = 0
11413 and then Nkind_In
(Rorig
, N_Op_Mod
, N_Op_Multiply
, N_Op_Divide
)
11415 -- For mod, we always give the warning, since the value is
11416 -- affected by the parenthesization (e.g. (-5) mod 315 /=
11417 -- -(5 mod 315)). But for the other cases, the only concern is
11418 -- overflow, e.g. for the case of 8 big signed (-(2 * 64)
11419 -- overflows, but (-2) * 64 does not). So we try to give the
11420 -- message only when overflow is possible.
11422 if Nkind
(Rorig
) /= N_Op_Mod
11423 and then Compile_Time_Known_Value
(R
)
11425 Val
:= Expr_Value
(R
);
11427 if Compile_Time_Known_Value
(Type_High_Bound
(Typ
)) then
11428 HB
:= Expr_Value
(Type_High_Bound
(Typ
));
11430 HB
:= Expr_Value
(Type_High_Bound
(Base_Type
(Typ
)));
11433 if Compile_Time_Known_Value
(Type_Low_Bound
(Typ
)) then
11434 LB
:= Expr_Value
(Type_Low_Bound
(Typ
));
11436 LB
:= Expr_Value
(Type_Low_Bound
(Base_Type
(Typ
)));
11439 -- Note that the test below is deliberately excluding the
11440 -- largest negative number, since that is a potentially
11441 -- troublesome case (e.g. -2 * x, where the result is the
11442 -- largest negative integer has an overflow with 2 * x).
11444 if Val
> LB
and then Val
<= HB
then
11449 -- For the multiplication case, the only case we have to worry
11450 -- about is when (-a)*b is exactly the largest negative number
11451 -- so that -(a*b) can cause overflow. This can only happen if
11452 -- a is a power of 2, and more generally if any operand is a
11453 -- constant that is not a power of 2, then the parentheses
11454 -- cannot affect whether overflow occurs. We only bother to
11455 -- test the left most operand
11457 -- Loop looking at left operands for one that has known value
11460 Opnd_Loop
: while Nkind
(Opnd
) = N_Op_Multiply
loop
11461 if Compile_Time_Known_Value
(Left_Opnd
(Opnd
)) then
11462 Lval
:= UI_Abs
(Expr_Value
(Left_Opnd
(Opnd
)));
11464 -- Operand value of 0 or 1 skips warning
11469 -- Otherwise check power of 2, if power of 2, warn, if
11470 -- anything else, skip warning.
11473 while Lval
/= 2 loop
11474 if Lval
mod 2 = 1 then
11485 -- Keep looking at left operands
11487 Opnd
:= Left_Opnd
(Opnd
);
11488 end loop Opnd_Loop
;
11490 -- For rem or "/" we can only have a problematic situation
11491 -- if the divisor has a value of minus one or one. Otherwise
11492 -- overflow is impossible (divisor > 1) or we have a case of
11493 -- division by zero in any case.
11495 if Nkind_In
(Rorig
, N_Op_Divide
, N_Op_Rem
)
11496 and then Compile_Time_Known_Value
(Right_Opnd
(Rorig
))
11497 and then UI_Abs
(Expr_Value
(Right_Opnd
(Rorig
))) /= 1
11502 -- If we fall through warning should be issued
11504 -- Shouldn't we test Warn_On_Questionable_Missing_Parens ???
11507 ("??unary minus expression should be parenthesized here!", N
);
11511 end Resolve_Unary_Op
;
11513 ----------------------------------
11514 -- Resolve_Unchecked_Expression --
11515 ----------------------------------
11517 procedure Resolve_Unchecked_Expression
11522 Resolve
(Expression
(N
), Typ
, Suppress
=> All_Checks
);
11523 Set_Etype
(N
, Typ
);
11524 end Resolve_Unchecked_Expression
;
11526 ---------------------------------------
11527 -- Resolve_Unchecked_Type_Conversion --
11528 ---------------------------------------
11530 procedure Resolve_Unchecked_Type_Conversion
11534 pragma Warnings
(Off
, Typ
);
11536 Operand
: constant Node_Id
:= Expression
(N
);
11537 Opnd_Type
: constant Entity_Id
:= Etype
(Operand
);
11540 -- Resolve operand using its own type
11542 Resolve
(Operand
, Opnd_Type
);
11544 -- In an inlined context, the unchecked conversion may be applied
11545 -- to a literal, in which case its type is the type of the context.
11546 -- (In other contexts conversions cannot apply to literals).
11549 and then (Opnd_Type
= Any_Character
or else
11550 Opnd_Type
= Any_Integer
or else
11551 Opnd_Type
= Any_Real
)
11553 Set_Etype
(Operand
, Typ
);
11556 Analyze_Dimension
(N
);
11557 Eval_Unchecked_Conversion
(N
);
11558 end Resolve_Unchecked_Type_Conversion
;
11560 ------------------------------
11561 -- Rewrite_Operator_As_Call --
11562 ------------------------------
11564 procedure Rewrite_Operator_As_Call
(N
: Node_Id
; Nam
: Entity_Id
) is
11565 Loc
: constant Source_Ptr
:= Sloc
(N
);
11566 Actuals
: constant List_Id
:= New_List
;
11570 if Nkind
(N
) in N_Binary_Op
then
11571 Append
(Left_Opnd
(N
), Actuals
);
11574 Append
(Right_Opnd
(N
), Actuals
);
11577 Make_Function_Call
(Sloc
=> Loc
,
11578 Name
=> New_Occurrence_Of
(Nam
, Loc
),
11579 Parameter_Associations
=> Actuals
);
11581 Preserve_Comes_From_Source
(New_N
, N
);
11582 Preserve_Comes_From_Source
(Name
(New_N
), N
);
11583 Rewrite
(N
, New_N
);
11584 Set_Etype
(N
, Etype
(Nam
));
11585 end Rewrite_Operator_As_Call
;
11587 ------------------------------
11588 -- Rewrite_Renamed_Operator --
11589 ------------------------------
11591 procedure Rewrite_Renamed_Operator
11596 Nam
: constant Name_Id
:= Chars
(Op
);
11597 Is_Binary
: constant Boolean := Nkind
(N
) in N_Binary_Op
;
11601 -- Do not perform this transformation within a pre/postcondition,
11602 -- because the expression will be reanalyzed, and the transformation
11603 -- might affect the visibility of the operator, e.g. in an instance.
11604 -- Note that fully analyzed and expanded pre/postconditions appear as
11605 -- pragma Check equivalents.
11607 if In_Pre_Post_Condition
(N
) then
11611 -- Likewise when an expression function is being preanalyzed, since the
11612 -- expression will be reanalyzed as part of the generated body.
11614 if In_Spec_Expression
then
11616 S
: constant Entity_Id
:= Current_Scope_No_Loops
;
11618 if Ekind
(S
) = E_Function
11619 and then Nkind
(Original_Node
(Unit_Declaration_Node
(S
))) =
11620 N_Expression_Function
11627 -- Rewrite the operator node using the real operator, not its renaming.
11628 -- Exclude user-defined intrinsic operations of the same name, which are
11629 -- treated separately and rewritten as calls.
11631 if Ekind
(Op
) /= E_Function
or else Chars
(N
) /= Nam
then
11632 Op_Node
:= New_Node
(Operator_Kind
(Nam
, Is_Binary
), Sloc
(N
));
11633 Set_Chars
(Op_Node
, Nam
);
11634 Set_Etype
(Op_Node
, Etype
(N
));
11635 Set_Entity
(Op_Node
, Op
);
11636 Set_Right_Opnd
(Op_Node
, Right_Opnd
(N
));
11638 -- Indicate that both the original entity and its renaming are
11639 -- referenced at this point.
11641 Generate_Reference
(Entity
(N
), N
);
11642 Generate_Reference
(Op
, N
);
11645 Set_Left_Opnd
(Op_Node
, Left_Opnd
(N
));
11648 Rewrite
(N
, Op_Node
);
11650 -- If the context type is private, add the appropriate conversions so
11651 -- that the operator is applied to the full view. This is done in the
11652 -- routines that resolve intrinsic operators.
11654 if Is_Intrinsic_Subprogram
(Op
) and then Is_Private_Type
(Typ
) then
11664 Resolve_Intrinsic_Operator
(N
, Typ
);
11670 Resolve_Intrinsic_Unary_Operator
(N
, Typ
);
11677 elsif Ekind
(Op
) = E_Function
and then Is_Intrinsic_Subprogram
(Op
) then
11679 -- Operator renames a user-defined operator of the same name. Use the
11680 -- original operator in the node, which is the one Gigi knows about.
11682 Set_Entity
(N
, Op
);
11683 Set_Is_Overloaded
(N
, False);
11685 end Rewrite_Renamed_Operator
;
11687 -----------------------
11688 -- Set_Slice_Subtype --
11689 -----------------------
11691 -- Build an implicit subtype declaration to represent the type delivered by
11692 -- the slice. This is an abbreviated version of an array subtype. We define
11693 -- an index subtype for the slice, using either the subtype name or the
11694 -- discrete range of the slice. To be consistent with index usage elsewhere
11695 -- we create a list header to hold the single index. This list is not
11696 -- otherwise attached to the syntax tree.
11698 procedure Set_Slice_Subtype
(N
: Node_Id
) is
11699 Loc
: constant Source_Ptr
:= Sloc
(N
);
11700 Index_List
: constant List_Id
:= New_List
;
11702 Index_Subtype
: Entity_Id
;
11703 Index_Type
: Entity_Id
;
11704 Slice_Subtype
: Entity_Id
;
11705 Drange
: constant Node_Id
:= Discrete_Range
(N
);
11708 Index_Type
:= Base_Type
(Etype
(Drange
));
11710 if Is_Entity_Name
(Drange
) then
11711 Index_Subtype
:= Entity
(Drange
);
11714 -- We force the evaluation of a range. This is definitely needed in
11715 -- the renamed case, and seems safer to do unconditionally. Note in
11716 -- any case that since we will create and insert an Itype referring
11717 -- to this range, we must make sure any side effect removal actions
11718 -- are inserted before the Itype definition.
11720 if Nkind
(Drange
) = N_Range
then
11721 Force_Evaluation
(Low_Bound
(Drange
));
11722 Force_Evaluation
(High_Bound
(Drange
));
11724 -- If the discrete range is given by a subtype indication, the
11725 -- type of the slice is the base of the subtype mark.
11727 elsif Nkind
(Drange
) = N_Subtype_Indication
then
11729 R
: constant Node_Id
:= Range_Expression
(Constraint
(Drange
));
11731 Index_Type
:= Base_Type
(Entity
(Subtype_Mark
(Drange
)));
11732 Force_Evaluation
(Low_Bound
(R
));
11733 Force_Evaluation
(High_Bound
(R
));
11737 Index_Subtype
:= Create_Itype
(Subtype_Kind
(Ekind
(Index_Type
)), N
);
11739 -- Take a new copy of Drange (where bounds have been rewritten to
11740 -- reference side-effect-free names). Using a separate tree ensures
11741 -- that further expansion (e.g. while rewriting a slice assignment
11742 -- into a FOR loop) does not attempt to remove side effects on the
11743 -- bounds again (which would cause the bounds in the index subtype
11744 -- definition to refer to temporaries before they are defined) (the
11745 -- reason is that some names are considered side effect free here
11746 -- for the subtype, but not in the context of a loop iteration
11749 Set_Scalar_Range
(Index_Subtype
, New_Copy_Tree
(Drange
));
11750 Set_Parent
(Scalar_Range
(Index_Subtype
), Index_Subtype
);
11751 Set_Etype
(Index_Subtype
, Index_Type
);
11752 Set_Size_Info
(Index_Subtype
, Index_Type
);
11753 Set_RM_Size
(Index_Subtype
, RM_Size
(Index_Type
));
11756 Slice_Subtype
:= Create_Itype
(E_Array_Subtype
, N
);
11758 Index
:= New_Occurrence_Of
(Index_Subtype
, Loc
);
11759 Set_Etype
(Index
, Index_Subtype
);
11760 Append
(Index
, Index_List
);
11762 Set_First_Index
(Slice_Subtype
, Index
);
11763 Set_Etype
(Slice_Subtype
, Base_Type
(Etype
(N
)));
11764 Set_Is_Constrained
(Slice_Subtype
, True);
11766 Check_Compile_Time_Size
(Slice_Subtype
);
11768 -- The Etype of the existing Slice node is reset to this slice subtype.
11769 -- Its bounds are obtained from its first index.
11771 Set_Etype
(N
, Slice_Subtype
);
11773 -- For bit-packed slice subtypes, freeze immediately (except in the case
11774 -- of being in a "spec expression" where we never freeze when we first
11775 -- see the expression).
11777 if Is_Bit_Packed_Array
(Slice_Subtype
) and not In_Spec_Expression
then
11778 Freeze_Itype
(Slice_Subtype
, N
);
11780 -- For all other cases insert an itype reference in the slice's actions
11781 -- so that the itype is frozen at the proper place in the tree (i.e. at
11782 -- the point where actions for the slice are analyzed). Note that this
11783 -- is different from freezing the itype immediately, which might be
11784 -- premature (e.g. if the slice is within a transient scope). This needs
11785 -- to be done only if expansion is enabled.
11787 elsif Expander_Active
then
11788 Ensure_Defined
(Typ
=> Slice_Subtype
, N
=> N
);
11790 end Set_Slice_Subtype
;
11792 --------------------------------
11793 -- Set_String_Literal_Subtype --
11794 --------------------------------
11796 procedure Set_String_Literal_Subtype
(N
: Node_Id
; Typ
: Entity_Id
) is
11797 Loc
: constant Source_Ptr
:= Sloc
(N
);
11798 Low_Bound
: constant Node_Id
:=
11799 Type_Low_Bound
(Etype
(First_Index
(Typ
)));
11800 Subtype_Id
: Entity_Id
;
11803 if Nkind
(N
) /= N_String_Literal
then
11807 Subtype_Id
:= Create_Itype
(E_String_Literal_Subtype
, N
);
11808 Set_String_Literal_Length
(Subtype_Id
, UI_From_Int
11809 (String_Length
(Strval
(N
))));
11810 Set_Etype
(Subtype_Id
, Base_Type
(Typ
));
11811 Set_Is_Constrained
(Subtype_Id
);
11812 Set_Etype
(N
, Subtype_Id
);
11814 -- The low bound is set from the low bound of the corresponding index
11815 -- type. Note that we do not store the high bound in the string literal
11816 -- subtype, but it can be deduced if necessary from the length and the
11819 if Is_OK_Static_Expression
(Low_Bound
) then
11820 Set_String_Literal_Low_Bound
(Subtype_Id
, Low_Bound
);
11822 -- If the lower bound is not static we create a range for the string
11823 -- literal, using the index type and the known length of the literal.
11824 -- The index type is not necessarily Positive, so the upper bound is
11825 -- computed as T'Val (T'Pos (Low_Bound) + L - 1).
11829 Index_List
: constant List_Id
:= New_List
;
11830 Index_Type
: constant Entity_Id
:= Etype
(First_Index
(Typ
));
11831 High_Bound
: constant Node_Id
:=
11832 Make_Attribute_Reference
(Loc
,
11833 Attribute_Name
=> Name_Val
,
11835 New_Occurrence_Of
(Index_Type
, Loc
),
11836 Expressions
=> New_List
(
11839 Make_Attribute_Reference
(Loc
,
11840 Attribute_Name
=> Name_Pos
,
11842 New_Occurrence_Of
(Index_Type
, Loc
),
11844 New_List
(New_Copy_Tree
(Low_Bound
))),
11846 Make_Integer_Literal
(Loc
,
11847 String_Length
(Strval
(N
)) - 1))));
11849 Array_Subtype
: Entity_Id
;
11852 Index_Subtype
: Entity_Id
;
11855 if Is_Integer_Type
(Index_Type
) then
11856 Set_String_Literal_Low_Bound
11857 (Subtype_Id
, Make_Integer_Literal
(Loc
, 1));
11860 -- If the index type is an enumeration type, build bounds
11861 -- expression with attributes.
11863 Set_String_Literal_Low_Bound
11865 Make_Attribute_Reference
(Loc
,
11866 Attribute_Name
=> Name_First
,
11868 New_Occurrence_Of
(Base_Type
(Index_Type
), Loc
)));
11869 Set_Etype
(String_Literal_Low_Bound
(Subtype_Id
), Index_Type
);
11872 Analyze_And_Resolve
(String_Literal_Low_Bound
(Subtype_Id
));
11874 -- Build bona fide subtype for the string, and wrap it in an
11875 -- unchecked conversion, because the backend expects the
11876 -- String_Literal_Subtype to have a static lower bound.
11879 Create_Itype
(Subtype_Kind
(Ekind
(Index_Type
)), N
);
11880 Drange
:= Make_Range
(Loc
, New_Copy_Tree
(Low_Bound
), High_Bound
);
11881 Set_Scalar_Range
(Index_Subtype
, Drange
);
11882 Set_Parent
(Drange
, N
);
11883 Analyze_And_Resolve
(Drange
, Index_Type
);
11885 -- In the context, the Index_Type may already have a constraint,
11886 -- so use common base type on string subtype. The base type may
11887 -- be used when generating attributes of the string, for example
11888 -- in the context of a slice assignment.
11890 Set_Etype
(Index_Subtype
, Base_Type
(Index_Type
));
11891 Set_Size_Info
(Index_Subtype
, Index_Type
);
11892 Set_RM_Size
(Index_Subtype
, RM_Size
(Index_Type
));
11894 Array_Subtype
:= Create_Itype
(E_Array_Subtype
, N
);
11896 Index
:= New_Occurrence_Of
(Index_Subtype
, Loc
);
11897 Set_Etype
(Index
, Index_Subtype
);
11898 Append
(Index
, Index_List
);
11900 Set_First_Index
(Array_Subtype
, Index
);
11901 Set_Etype
(Array_Subtype
, Base_Type
(Typ
));
11902 Set_Is_Constrained
(Array_Subtype
, True);
11905 Make_Unchecked_Type_Conversion
(Loc
,
11906 Subtype_Mark
=> New_Occurrence_Of
(Array_Subtype
, Loc
),
11907 Expression
=> Relocate_Node
(N
)));
11908 Set_Etype
(N
, Array_Subtype
);
11911 end Set_String_Literal_Subtype
;
11913 ------------------------------
11914 -- Simplify_Type_Conversion --
11915 ------------------------------
11917 procedure Simplify_Type_Conversion
(N
: Node_Id
) is
11919 if Nkind
(N
) = N_Type_Conversion
then
11921 Operand
: constant Node_Id
:= Expression
(N
);
11922 Target_Typ
: constant Entity_Id
:= Etype
(N
);
11923 Opnd_Typ
: constant Entity_Id
:= Etype
(Operand
);
11926 -- Special processing if the conversion is the expression of a
11927 -- Rounding or Truncation attribute reference. In this case we
11930 -- ityp (ftyp'Rounding (x)) or ityp (ftyp'Truncation (x))
11936 -- with the Float_Truncate flag set to False or True respectively,
11937 -- which is more efficient.
11939 if Is_Floating_Point_Type
(Opnd_Typ
)
11941 (Is_Integer_Type
(Target_Typ
)
11942 or else (Is_Fixed_Point_Type
(Target_Typ
)
11943 and then Conversion_OK
(N
)))
11944 and then Nkind
(Operand
) = N_Attribute_Reference
11945 and then Nam_In
(Attribute_Name
(Operand
), Name_Rounding
,
11949 Truncate
: constant Boolean :=
11950 Attribute_Name
(Operand
) = Name_Truncation
;
11953 Relocate_Node
(First
(Expressions
(Operand
))));
11954 Set_Float_Truncate
(N
, Truncate
);
11959 end Simplify_Type_Conversion
;
11961 -----------------------------
11962 -- Unique_Fixed_Point_Type --
11963 -----------------------------
11965 function Unique_Fixed_Point_Type
(N
: Node_Id
) return Entity_Id
is
11966 procedure Fixed_Point_Error
(T1
: Entity_Id
; T2
: Entity_Id
);
11967 -- Give error messages for true ambiguity. Messages are posted on node
11968 -- N, and entities T1, T2 are the possible interpretations.
11970 -----------------------
11971 -- Fixed_Point_Error --
11972 -----------------------
11974 procedure Fixed_Point_Error
(T1
: Entity_Id
; T2
: Entity_Id
) is
11976 Error_Msg_N
("ambiguous universal_fixed_expression", N
);
11977 Error_Msg_NE
("\\possible interpretation as}", N
, T1
);
11978 Error_Msg_NE
("\\possible interpretation as}", N
, T2
);
11979 end Fixed_Point_Error
;
11989 -- Start of processing for Unique_Fixed_Point_Type
11992 -- The operations on Duration are visible, so Duration is always a
11993 -- possible interpretation.
11995 T1
:= Standard_Duration
;
11997 -- Look for fixed-point types in enclosing scopes
11999 Scop
:= Current_Scope
;
12000 while Scop
/= Standard_Standard
loop
12001 T2
:= First_Entity
(Scop
);
12002 while Present
(T2
) loop
12003 if Is_Fixed_Point_Type
(T2
)
12004 and then Current_Entity
(T2
) = T2
12005 and then Scope
(Base_Type
(T2
)) = Scop
12007 if Present
(T1
) then
12008 Fixed_Point_Error
(T1
, T2
);
12018 Scop
:= Scope
(Scop
);
12021 -- Look for visible fixed type declarations in the context
12023 Item
:= First
(Context_Items
(Cunit
(Current_Sem_Unit
)));
12024 while Present
(Item
) loop
12025 if Nkind
(Item
) = N_With_Clause
then
12026 Scop
:= Entity
(Name
(Item
));
12027 T2
:= First_Entity
(Scop
);
12028 while Present
(T2
) loop
12029 if Is_Fixed_Point_Type
(T2
)
12030 and then Scope
(Base_Type
(T2
)) = Scop
12031 and then (Is_Potentially_Use_Visible
(T2
) or else In_Use
(T2
))
12033 if Present
(T1
) then
12034 Fixed_Point_Error
(T1
, T2
);
12048 if Nkind
(N
) = N_Real_Literal
then
12049 Error_Msg_NE
("??real literal interpreted as }!", N
, T1
);
12052 -- When the context is a type conversion, issue the warning on the
12053 -- expression of the conversion because it is the actual operation.
12055 if Nkind_In
(N
, N_Type_Conversion
, N_Unchecked_Type_Conversion
) then
12056 ErrN
:= Expression
(N
);
12062 ("??universal_fixed expression interpreted as }!", ErrN
, T1
);
12066 end Unique_Fixed_Point_Type
;
12068 ----------------------
12069 -- Valid_Conversion --
12070 ----------------------
12072 function Valid_Conversion
12074 Target
: Entity_Id
;
12076 Report_Errs
: Boolean := True) return Boolean
12078 Target_Type
: constant Entity_Id
:= Base_Type
(Target
);
12079 Opnd_Type
: Entity_Id
:= Etype
(Operand
);
12080 Inc_Ancestor
: Entity_Id
;
12082 function Conversion_Check
12084 Msg
: String) return Boolean;
12085 -- Little routine to post Msg if Valid is False, returns Valid value
12087 procedure Conversion_Error_N
(Msg
: String; N
: Node_Or_Entity_Id
);
12088 -- If Report_Errs, then calls Errout.Error_Msg_N with its arguments
12090 procedure Conversion_Error_NE
12092 N
: Node_Or_Entity_Id
;
12093 E
: Node_Or_Entity_Id
);
12094 -- If Report_Errs, then calls Errout.Error_Msg_NE with its arguments
12096 function In_Instance_Code
return Boolean;
12097 -- Return True if expression is within an instance but is not in one of
12098 -- the actuals of the instantiation. Type conversions within an instance
12099 -- are not rechecked because type visbility may lead to spurious errors,
12100 -- but conversions in an actual for a formal object must be checked.
12102 function Valid_Tagged_Conversion
12103 (Target_Type
: Entity_Id
;
12104 Opnd_Type
: Entity_Id
) return Boolean;
12105 -- Specifically test for validity of tagged conversions
12107 function Valid_Array_Conversion
return Boolean;
12108 -- Check index and component conformance, and accessibility levels if
12109 -- the component types are anonymous access types (Ada 2005).
12111 ----------------------
12112 -- Conversion_Check --
12113 ----------------------
12115 function Conversion_Check
12117 Msg
: String) return Boolean
12122 -- A generic unit has already been analyzed and we have verified
12123 -- that a particular conversion is OK in that context. Since the
12124 -- instance is reanalyzed without relying on the relationships
12125 -- established during the analysis of the generic, it is possible
12126 -- to end up with inconsistent views of private types. Do not emit
12127 -- the error message in such cases. The rest of the machinery in
12128 -- Valid_Conversion still ensures the proper compatibility of
12129 -- target and operand types.
12131 and then not In_Instance_Code
12133 Conversion_Error_N
(Msg
, Operand
);
12137 end Conversion_Check
;
12139 ------------------------
12140 -- Conversion_Error_N --
12141 ------------------------
12143 procedure Conversion_Error_N
(Msg
: String; N
: Node_Or_Entity_Id
) is
12145 if Report_Errs
then
12146 Error_Msg_N
(Msg
, N
);
12148 end Conversion_Error_N
;
12150 -------------------------
12151 -- Conversion_Error_NE --
12152 -------------------------
12154 procedure Conversion_Error_NE
12156 N
: Node_Or_Entity_Id
;
12157 E
: Node_Or_Entity_Id
)
12160 if Report_Errs
then
12161 Error_Msg_NE
(Msg
, N
, E
);
12163 end Conversion_Error_NE
;
12165 ----------------------
12166 -- In_Instance_Code --
12167 ----------------------
12169 function In_Instance_Code
return Boolean is
12173 if not In_Instance
then
12178 while Present
(Par
) loop
12180 -- The expression is part of an actual object if it appears in
12181 -- the generated object declaration in the instance.
12183 if Nkind
(Par
) = N_Object_Declaration
12184 and then Present
(Corresponding_Generic_Association
(Par
))
12190 Nkind
(Par
) in N_Statement_Other_Than_Procedure_Call
12191 or else Nkind
(Par
) in N_Subprogram_Call
12192 or else Nkind
(Par
) in N_Declaration
;
12195 Par
:= Parent
(Par
);
12198 -- Otherwise the expression appears within the instantiated unit
12202 end In_Instance_Code
;
12204 ----------------------------
12205 -- Valid_Array_Conversion --
12206 ----------------------------
12208 function Valid_Array_Conversion
return Boolean is
12209 Opnd_Comp_Type
: constant Entity_Id
:= Component_Type
(Opnd_Type
);
12210 Opnd_Comp_Base
: constant Entity_Id
:= Base_Type
(Opnd_Comp_Type
);
12212 Opnd_Index
: Node_Id
;
12213 Opnd_Index_Type
: Entity_Id
;
12215 Target_Comp_Type
: constant Entity_Id
:=
12216 Component_Type
(Target_Type
);
12217 Target_Comp_Base
: constant Entity_Id
:=
12218 Base_Type
(Target_Comp_Type
);
12220 Target_Index
: Node_Id
;
12221 Target_Index_Type
: Entity_Id
;
12224 -- Error if wrong number of dimensions
12227 Number_Dimensions
(Target_Type
) /= Number_Dimensions
(Opnd_Type
)
12230 ("incompatible number of dimensions for conversion", Operand
);
12233 -- Number of dimensions matches
12236 -- Loop through indexes of the two arrays
12238 Target_Index
:= First_Index
(Target_Type
);
12239 Opnd_Index
:= First_Index
(Opnd_Type
);
12240 while Present
(Target_Index
) and then Present
(Opnd_Index
) loop
12241 Target_Index_Type
:= Etype
(Target_Index
);
12242 Opnd_Index_Type
:= Etype
(Opnd_Index
);
12244 -- Error if index types are incompatible
12246 if not (Is_Integer_Type
(Target_Index_Type
)
12247 and then Is_Integer_Type
(Opnd_Index_Type
))
12248 and then (Root_Type
(Target_Index_Type
)
12249 /= Root_Type
(Opnd_Index_Type
))
12252 ("incompatible index types for array conversion",
12257 Next_Index
(Target_Index
);
12258 Next_Index
(Opnd_Index
);
12261 -- If component types have same base type, all set
12263 if Target_Comp_Base
= Opnd_Comp_Base
then
12266 -- Here if base types of components are not the same. The only
12267 -- time this is allowed is if we have anonymous access types.
12269 -- The conversion of arrays of anonymous access types can lead
12270 -- to dangling pointers. AI-392 formalizes the accessibility
12271 -- checks that must be applied to such conversions to prevent
12272 -- out-of-scope references.
12275 (Target_Comp_Base
, E_Anonymous_Access_Type
,
12276 E_Anonymous_Access_Subprogram_Type
)
12277 and then Ekind
(Opnd_Comp_Base
) = Ekind
(Target_Comp_Base
)
12279 Subtypes_Statically_Match
(Target_Comp_Type
, Opnd_Comp_Type
)
12281 if Type_Access_Level
(Target_Type
) <
12282 Deepest_Type_Access_Level
(Opnd_Type
)
12284 if In_Instance_Body
then
12285 Error_Msg_Warn
:= SPARK_Mode
/= On
;
12287 ("source array type has deeper accessibility "
12288 & "level than target<<", Operand
);
12289 Conversion_Error_N
("\Program_Error [<<", Operand
);
12291 Make_Raise_Program_Error
(Sloc
(N
),
12292 Reason
=> PE_Accessibility_Check_Failed
));
12293 Set_Etype
(N
, Target_Type
);
12296 -- Conversion not allowed because of accessibility levels
12300 ("source array type has deeper accessibility "
12301 & "level than target", Operand
);
12309 -- All other cases where component base types do not match
12313 ("incompatible component types for array conversion",
12318 -- Check that component subtypes statically match. For numeric
12319 -- types this means that both must be either constrained or
12320 -- unconstrained. For enumeration types the bounds must match.
12321 -- All of this is checked in Subtypes_Statically_Match.
12323 if not Subtypes_Statically_Match
12324 (Target_Comp_Type
, Opnd_Comp_Type
)
12327 ("component subtypes must statically match", Operand
);
12333 end Valid_Array_Conversion
;
12335 -----------------------------
12336 -- Valid_Tagged_Conversion --
12337 -----------------------------
12339 function Valid_Tagged_Conversion
12340 (Target_Type
: Entity_Id
;
12341 Opnd_Type
: Entity_Id
) return Boolean
12344 -- Upward conversions are allowed (RM 4.6(22))
12346 if Covers
(Target_Type
, Opnd_Type
)
12347 or else Is_Ancestor
(Target_Type
, Opnd_Type
)
12351 -- Downward conversion are allowed if the operand is class-wide
12354 elsif Is_Class_Wide_Type
(Opnd_Type
)
12355 and then Covers
(Opnd_Type
, Target_Type
)
12359 elsif Covers
(Opnd_Type
, Target_Type
)
12360 or else Is_Ancestor
(Opnd_Type
, Target_Type
)
12363 Conversion_Check
(False,
12364 "downward conversion of tagged objects not allowed");
12366 -- Ada 2005 (AI-251): The conversion to/from interface types is
12367 -- always valid. The types involved may be class-wide (sub)types.
12369 elsif Is_Interface
(Etype
(Base_Type
(Target_Type
)))
12370 or else Is_Interface
(Etype
(Base_Type
(Opnd_Type
)))
12374 -- If the operand is a class-wide type obtained through a limited_
12375 -- with clause, and the context includes the nonlimited view, use
12376 -- it to determine whether the conversion is legal.
12378 elsif Is_Class_Wide_Type
(Opnd_Type
)
12379 and then From_Limited_With
(Opnd_Type
)
12380 and then Present
(Non_Limited_View
(Etype
(Opnd_Type
)))
12381 and then Is_Interface
(Non_Limited_View
(Etype
(Opnd_Type
)))
12385 elsif Is_Access_Type
(Opnd_Type
)
12386 and then Is_Interface
(Directly_Designated_Type
(Opnd_Type
))
12391 Conversion_Error_NE
12392 ("invalid tagged conversion, not compatible with}",
12393 N
, First_Subtype
(Opnd_Type
));
12396 end Valid_Tagged_Conversion
;
12398 -- Start of processing for Valid_Conversion
12401 Check_Parameterless_Call
(Operand
);
12403 if Is_Overloaded
(Operand
) then
12413 -- Remove procedure calls, which syntactically cannot appear in
12414 -- this context, but which cannot be removed by type checking,
12415 -- because the context does not impose a type.
12417 -- The node may be labelled overloaded, but still contain only one
12418 -- interpretation because others were discarded earlier. If this
12419 -- is the case, retain the single interpretation if legal.
12421 Get_First_Interp
(Operand
, I
, It
);
12422 Opnd_Type
:= It
.Typ
;
12423 Get_Next_Interp
(I
, It
);
12425 if Present
(It
.Typ
)
12426 and then Opnd_Type
/= Standard_Void_Type
12428 -- More than one candidate interpretation is available
12430 Get_First_Interp
(Operand
, I
, It
);
12431 while Present
(It
.Typ
) loop
12432 if It
.Typ
= Standard_Void_Type
then
12436 -- When compiling for a system where Address is of a visible
12437 -- integer type, spurious ambiguities can be produced when
12438 -- arithmetic operations have a literal operand and return
12439 -- System.Address or a descendant of it. These ambiguities
12440 -- are usually resolved by the context, but for conversions
12441 -- there is no context type and the removal of the spurious
12442 -- operations must be done explicitly here.
12444 if not Address_Is_Private
12445 and then Is_Descendant_Of_Address
(It
.Typ
)
12450 Get_Next_Interp
(I
, It
);
12454 Get_First_Interp
(Operand
, I
, It
);
12458 if No
(It
.Typ
) then
12459 Conversion_Error_N
("illegal operand in conversion", Operand
);
12463 Get_Next_Interp
(I
, It
);
12465 if Present
(It
.Typ
) then
12468 It1
:= Disambiguate
(Operand
, I1
, I
, Any_Type
);
12470 if It1
= No_Interp
then
12472 ("ambiguous operand in conversion", Operand
);
12474 -- If the interpretation involves a standard operator, use
12475 -- the location of the type, which may be user-defined.
12477 if Sloc
(It
.Nam
) = Standard_Location
then
12478 Error_Msg_Sloc
:= Sloc
(It
.Typ
);
12480 Error_Msg_Sloc
:= Sloc
(It
.Nam
);
12483 Conversion_Error_N
-- CODEFIX
12484 ("\\possible interpretation#!", Operand
);
12486 if Sloc
(N1
) = Standard_Location
then
12487 Error_Msg_Sloc
:= Sloc
(T1
);
12489 Error_Msg_Sloc
:= Sloc
(N1
);
12492 Conversion_Error_N
-- CODEFIX
12493 ("\\possible interpretation#!", Operand
);
12499 Set_Etype
(Operand
, It1
.Typ
);
12500 Opnd_Type
:= It1
.Typ
;
12504 -- Deal with conversion of integer type to address if the pragma
12505 -- Allow_Integer_Address is in effect. We convert the conversion to
12506 -- an unchecked conversion in this case and we are all done.
12508 if Address_Integer_Convert_OK
(Opnd_Type
, Target_Type
) then
12509 Rewrite
(N
, Unchecked_Convert_To
(Target_Type
, Expression
(N
)));
12510 Analyze_And_Resolve
(N
, Target_Type
);
12514 -- If we are within a child unit, check whether the type of the
12515 -- expression has an ancestor in a parent unit, in which case it
12516 -- belongs to its derivation class even if the ancestor is private.
12517 -- See RM 7.3.1 (5.2/3).
12519 Inc_Ancestor
:= Get_Incomplete_View_Of_Ancestor
(Opnd_Type
);
12523 if Is_Numeric_Type
(Target_Type
) then
12525 -- A universal fixed expression can be converted to any numeric type
12527 if Opnd_Type
= Universal_Fixed
then
12530 -- Also no need to check when in an instance or inlined body, because
12531 -- the legality has been established when the template was analyzed.
12532 -- Furthermore, numeric conversions may occur where only a private
12533 -- view of the operand type is visible at the instantiation point.
12534 -- This results in a spurious error if we check that the operand type
12535 -- is a numeric type.
12537 -- Note: in a previous version of this unit, the following tests were
12538 -- applied only for generated code (Comes_From_Source set to False),
12539 -- but in fact the test is required for source code as well, since
12540 -- this situation can arise in source code.
12542 elsif In_Instance_Code
or else In_Inlined_Body
then
12545 -- Otherwise we need the conversion check
12548 return Conversion_Check
12549 (Is_Numeric_Type
(Opnd_Type
)
12551 (Present
(Inc_Ancestor
)
12552 and then Is_Numeric_Type
(Inc_Ancestor
)),
12553 "illegal operand for numeric conversion");
12558 elsif Is_Array_Type
(Target_Type
) then
12559 if not Is_Array_Type
(Opnd_Type
)
12560 or else Opnd_Type
= Any_Composite
12561 or else Opnd_Type
= Any_String
12564 ("illegal operand for array conversion", Operand
);
12568 return Valid_Array_Conversion
;
12571 -- Ada 2005 (AI-251): Internally generated conversions of access to
12572 -- interface types added to force the displacement of the pointer to
12573 -- reference the corresponding dispatch table.
12575 elsif not Comes_From_Source
(N
)
12576 and then Is_Access_Type
(Target_Type
)
12577 and then Is_Interface
(Designated_Type
(Target_Type
))
12581 -- Ada 2005 (AI-251): Anonymous access types where target references an
12584 elsif Is_Access_Type
(Opnd_Type
)
12585 and then Ekind_In
(Target_Type
, E_General_Access_Type
,
12586 E_Anonymous_Access_Type
)
12587 and then Is_Interface
(Directly_Designated_Type
(Target_Type
))
12589 -- Check the static accessibility rule of 4.6(17). Note that the
12590 -- check is not enforced when within an instance body, since the
12591 -- RM requires such cases to be caught at run time.
12593 -- If the operand is a rewriting of an allocator no check is needed
12594 -- because there are no accessibility issues.
12596 if Nkind
(Original_Node
(N
)) = N_Allocator
then
12599 elsif Ekind
(Target_Type
) /= E_Anonymous_Access_Type
then
12600 if Type_Access_Level
(Opnd_Type
) >
12601 Deepest_Type_Access_Level
(Target_Type
)
12603 -- In an instance, this is a run-time check, but one we know
12604 -- will fail, so generate an appropriate warning. The raise
12605 -- will be generated by Expand_N_Type_Conversion.
12607 if In_Instance_Body
then
12608 Error_Msg_Warn
:= SPARK_Mode
/= On
;
12610 ("cannot convert local pointer to non-local access type<<",
12612 Conversion_Error_N
("\Program_Error [<<", Operand
);
12616 ("cannot convert local pointer to non-local access type",
12621 -- Special accessibility checks are needed in the case of access
12622 -- discriminants declared for a limited type.
12624 elsif Ekind
(Opnd_Type
) = E_Anonymous_Access_Type
12625 and then not Is_Local_Anonymous_Access
(Opnd_Type
)
12627 -- When the operand is a selected access discriminant the check
12628 -- needs to be made against the level of the object denoted by
12629 -- the prefix of the selected name (Object_Access_Level handles
12630 -- checking the prefix of the operand for this case).
12632 if Nkind
(Operand
) = N_Selected_Component
12633 and then Object_Access_Level
(Operand
) >
12634 Deepest_Type_Access_Level
(Target_Type
)
12636 -- In an instance, this is a run-time check, but one we know
12637 -- will fail, so generate an appropriate warning. The raise
12638 -- will be generated by Expand_N_Type_Conversion.
12640 if In_Instance_Body
then
12641 Error_Msg_Warn
:= SPARK_Mode
/= On
;
12643 ("cannot convert access discriminant to non-local "
12644 & "access type<<", Operand
);
12645 Conversion_Error_N
("\Program_Error [<<", Operand
);
12647 -- Real error if not in instance body
12651 ("cannot convert access discriminant to non-local "
12652 & "access type", Operand
);
12657 -- The case of a reference to an access discriminant from
12658 -- within a limited type declaration (which will appear as
12659 -- a discriminal) is always illegal because the level of the
12660 -- discriminant is considered to be deeper than any (nameable)
12663 if Is_Entity_Name
(Operand
)
12664 and then not Is_Local_Anonymous_Access
(Opnd_Type
)
12666 Ekind_In
(Entity
(Operand
), E_In_Parameter
, E_Constant
)
12667 and then Present
(Discriminal_Link
(Entity
(Operand
)))
12670 ("discriminant has deeper accessibility level than target",
12679 -- General and anonymous access types
12681 elsif Ekind_In
(Target_Type
, E_General_Access_Type
,
12682 E_Anonymous_Access_Type
)
12685 (Is_Access_Type
(Opnd_Type
)
12687 Ekind_In
(Opnd_Type
, E_Access_Subprogram_Type
,
12688 E_Access_Protected_Subprogram_Type
),
12689 "must be an access-to-object type")
12691 if Is_Access_Constant
(Opnd_Type
)
12692 and then not Is_Access_Constant
(Target_Type
)
12695 ("access-to-constant operand type not allowed", Operand
);
12699 -- Check the static accessibility rule of 4.6(17). Note that the
12700 -- check is not enforced when within an instance body, since the RM
12701 -- requires such cases to be caught at run time.
12703 if Ekind
(Target_Type
) /= E_Anonymous_Access_Type
12704 or else Is_Local_Anonymous_Access
(Target_Type
)
12705 or else Nkind
(Associated_Node_For_Itype
(Target_Type
)) =
12706 N_Object_Declaration
12708 -- Ada 2012 (AI05-0149): Perform legality checking on implicit
12709 -- conversions from an anonymous access type to a named general
12710 -- access type. Such conversions are not allowed in the case of
12711 -- access parameters and stand-alone objects of an anonymous
12712 -- access type. The implicit conversion case is recognized by
12713 -- testing that Comes_From_Source is False and that it's been
12714 -- rewritten. The Comes_From_Source test isn't sufficient because
12715 -- nodes in inlined calls to predefined library routines can have
12716 -- Comes_From_Source set to False. (Is there a better way to test
12717 -- for implicit conversions???)
12719 if Ada_Version
>= Ada_2012
12720 and then not Comes_From_Source
(N
)
12721 and then N
/= Original_Node
(N
)
12722 and then Ekind
(Target_Type
) = E_General_Access_Type
12723 and then Ekind
(Opnd_Type
) = E_Anonymous_Access_Type
12725 if Is_Itype
(Opnd_Type
) then
12727 -- Implicit conversions aren't allowed for objects of an
12728 -- anonymous access type, since such objects have nonstatic
12729 -- levels in Ada 2012.
12731 if Nkind
(Associated_Node_For_Itype
(Opnd_Type
)) =
12732 N_Object_Declaration
12735 ("implicit conversion of stand-alone anonymous "
12736 & "access object not allowed", Operand
);
12739 -- Implicit conversions aren't allowed for anonymous access
12740 -- parameters. The "not Is_Local_Anonymous_Access_Type" test
12741 -- is done to exclude anonymous access results.
12743 elsif not Is_Local_Anonymous_Access
(Opnd_Type
)
12744 and then Nkind_In
(Associated_Node_For_Itype
(Opnd_Type
),
12745 N_Function_Specification
,
12746 N_Procedure_Specification
)
12749 ("implicit conversion of anonymous access formal "
12750 & "not allowed", Operand
);
12753 -- This is a case where there's an enclosing object whose
12754 -- to which the "statically deeper than" relationship does
12755 -- not apply (such as an access discriminant selected from
12756 -- a dereference of an access parameter).
12758 elsif Object_Access_Level
(Operand
)
12759 = Scope_Depth
(Standard_Standard
)
12762 ("implicit conversion of anonymous access value "
12763 & "not allowed", Operand
);
12766 -- In other cases, the level of the operand's type must be
12767 -- statically less deep than that of the target type, else
12768 -- implicit conversion is disallowed (by RM12-8.6(27.1/3)).
12770 elsif Type_Access_Level
(Opnd_Type
) >
12771 Deepest_Type_Access_Level
(Target_Type
)
12774 ("implicit conversion of anonymous access value "
12775 & "violates accessibility", Operand
);
12780 elsif Type_Access_Level
(Opnd_Type
) >
12781 Deepest_Type_Access_Level
(Target_Type
)
12783 -- In an instance, this is a run-time check, but one we know
12784 -- will fail, so generate an appropriate warning. The raise
12785 -- will be generated by Expand_N_Type_Conversion.
12787 if In_Instance_Body
then
12788 Error_Msg_Warn
:= SPARK_Mode
/= On
;
12790 ("cannot convert local pointer to non-local access type<<",
12792 Conversion_Error_N
("\Program_Error [<<", Operand
);
12794 -- If not in an instance body, this is a real error
12797 -- Avoid generation of spurious error message
12799 if not Error_Posted
(N
) then
12801 ("cannot convert local pointer to non-local access type",
12808 -- Special accessibility checks are needed in the case of access
12809 -- discriminants declared for a limited type.
12811 elsif Ekind
(Opnd_Type
) = E_Anonymous_Access_Type
12812 and then not Is_Local_Anonymous_Access
(Opnd_Type
)
12814 -- When the operand is a selected access discriminant the check
12815 -- needs to be made against the level of the object denoted by
12816 -- the prefix of the selected name (Object_Access_Level handles
12817 -- checking the prefix of the operand for this case).
12819 if Nkind
(Operand
) = N_Selected_Component
12820 and then Object_Access_Level
(Operand
) >
12821 Deepest_Type_Access_Level
(Target_Type
)
12823 -- In an instance, this is a run-time check, but one we know
12824 -- will fail, so generate an appropriate warning. The raise
12825 -- will be generated by Expand_N_Type_Conversion.
12827 if In_Instance_Body
then
12828 Error_Msg_Warn
:= SPARK_Mode
/= On
;
12830 ("cannot convert access discriminant to non-local "
12831 & "access type<<", Operand
);
12832 Conversion_Error_N
("\Program_Error [<<", Operand
);
12834 -- If not in an instance body, this is a real error
12838 ("cannot convert access discriminant to non-local "
12839 & "access type", Operand
);
12844 -- The case of a reference to an access discriminant from
12845 -- within a limited type declaration (which will appear as
12846 -- a discriminal) is always illegal because the level of the
12847 -- discriminant is considered to be deeper than any (nameable)
12850 if Is_Entity_Name
(Operand
)
12852 Ekind_In
(Entity
(Operand
), E_In_Parameter
, E_Constant
)
12853 and then Present
(Discriminal_Link
(Entity
(Operand
)))
12856 ("discriminant has deeper accessibility level than target",
12863 -- In the presence of limited_with clauses we have to use nonlimited
12864 -- views, if available.
12866 Check_Limited
: declare
12867 function Full_Designated_Type
(T
: Entity_Id
) return Entity_Id
;
12868 -- Helper function to handle limited views
12870 --------------------------
12871 -- Full_Designated_Type --
12872 --------------------------
12874 function Full_Designated_Type
(T
: Entity_Id
) return Entity_Id
is
12875 Desig
: constant Entity_Id
:= Designated_Type
(T
);
12878 -- Handle the limited view of a type
12880 if From_Limited_With
(Desig
)
12881 and then Has_Non_Limited_View
(Desig
)
12883 return Available_View
(Desig
);
12887 end Full_Designated_Type
;
12889 -- Local Declarations
12891 Target
: constant Entity_Id
:= Full_Designated_Type
(Target_Type
);
12892 Opnd
: constant Entity_Id
:= Full_Designated_Type
(Opnd_Type
);
12894 Same_Base
: constant Boolean :=
12895 Base_Type
(Target
) = Base_Type
(Opnd
);
12897 -- Start of processing for Check_Limited
12900 if Is_Tagged_Type
(Target
) then
12901 return Valid_Tagged_Conversion
(Target
, Opnd
);
12904 if not Same_Base
then
12905 Conversion_Error_NE
12906 ("target designated type not compatible with }",
12907 N
, Base_Type
(Opnd
));
12910 -- Ada 2005 AI-384: legality rule is symmetric in both
12911 -- designated types. The conversion is legal (with possible
12912 -- constraint check) if either designated type is
12915 elsif Subtypes_Statically_Match
(Target
, Opnd
)
12917 (Has_Discriminants
(Target
)
12919 (not Is_Constrained
(Opnd
)
12920 or else not Is_Constrained
(Target
)))
12922 -- Special case, if Value_Size has been used to make the
12923 -- sizes different, the conversion is not allowed even
12924 -- though the subtypes statically match.
12926 if Known_Static_RM_Size
(Target
)
12927 and then Known_Static_RM_Size
(Opnd
)
12928 and then RM_Size
(Target
) /= RM_Size
(Opnd
)
12930 Conversion_Error_NE
12931 ("target designated subtype not compatible with }",
12933 Conversion_Error_NE
12934 ("\because sizes of the two designated subtypes differ",
12938 -- Normal case where conversion is allowed
12946 ("target designated subtype not compatible with }",
12953 -- Access to subprogram types. If the operand is an access parameter,
12954 -- the type has a deeper accessibility that any master, and cannot be
12955 -- assigned. We must make an exception if the conversion is part of an
12956 -- assignment and the target is the return object of an extended return
12957 -- statement, because in that case the accessibility check takes place
12958 -- after the return.
12960 elsif Is_Access_Subprogram_Type
(Target_Type
)
12962 -- Note: this test of Opnd_Type is there to prevent entering this
12963 -- branch in the case of a remote access to subprogram type, which
12964 -- is internally represented as an E_Record_Type.
12966 and then Is_Access_Type
(Opnd_Type
)
12968 if Ekind
(Base_Type
(Opnd_Type
)) = E_Anonymous_Access_Subprogram_Type
12969 and then Is_Entity_Name
(Operand
)
12970 and then Ekind
(Entity
(Operand
)) = E_In_Parameter
12972 (Nkind
(Parent
(N
)) /= N_Assignment_Statement
12973 or else not Is_Entity_Name
(Name
(Parent
(N
)))
12974 or else not Is_Return_Object
(Entity
(Name
(Parent
(N
)))))
12977 ("illegal attempt to store anonymous access to subprogram",
12980 ("\value has deeper accessibility than any master "
12981 & "(RM 3.10.2 (13))",
12985 ("\use named access type for& instead of access parameter",
12986 Operand
, Entity
(Operand
));
12989 -- Check that the designated types are subtype conformant
12991 Check_Subtype_Conformant
(New_Id
=> Designated_Type
(Target_Type
),
12992 Old_Id
=> Designated_Type
(Opnd_Type
),
12995 -- Check the static accessibility rule of 4.6(20)
12997 if Type_Access_Level
(Opnd_Type
) >
12998 Deepest_Type_Access_Level
(Target_Type
)
13001 ("operand type has deeper accessibility level than target",
13004 -- Check that if the operand type is declared in a generic body,
13005 -- then the target type must be declared within that same body
13006 -- (enforces last sentence of 4.6(20)).
13008 elsif Present
(Enclosing_Generic_Body
(Opnd_Type
)) then
13010 O_Gen
: constant Node_Id
:=
13011 Enclosing_Generic_Body
(Opnd_Type
);
13016 T_Gen
:= Enclosing_Generic_Body
(Target_Type
);
13017 while Present
(T_Gen
) and then T_Gen
/= O_Gen
loop
13018 T_Gen
:= Enclosing_Generic_Body
(T_Gen
);
13021 if T_Gen
/= O_Gen
then
13023 ("target type must be declared in same generic body "
13024 & "as operand type", N
);
13031 -- Remote access to subprogram types
13033 elsif Is_Remote_Access_To_Subprogram_Type
(Target_Type
)
13034 and then Is_Remote_Access_To_Subprogram_Type
(Opnd_Type
)
13036 -- It is valid to convert from one RAS type to another provided
13037 -- that their specification statically match.
13039 -- Note: at this point, remote access to subprogram types have been
13040 -- expanded to their E_Record_Type representation, and we need to
13041 -- go back to the original access type definition using the
13042 -- Corresponding_Remote_Type attribute in order to check that the
13043 -- designated profiles match.
13045 pragma Assert
(Ekind
(Target_Type
) = E_Record_Type
);
13046 pragma Assert
(Ekind
(Opnd_Type
) = E_Record_Type
);
13048 Check_Subtype_Conformant
13050 Designated_Type
(Corresponding_Remote_Type
(Target_Type
)),
13052 Designated_Type
(Corresponding_Remote_Type
(Opnd_Type
)),
13057 -- If it was legal in the generic, it's legal in the instance
13059 elsif In_Instance_Body
then
13062 -- If both are tagged types, check legality of view conversions
13064 elsif Is_Tagged_Type
(Target_Type
)
13066 Is_Tagged_Type
(Opnd_Type
)
13068 return Valid_Tagged_Conversion
(Target_Type
, Opnd_Type
);
13070 -- Types derived from the same root type are convertible
13072 elsif Root_Type
(Target_Type
) = Root_Type
(Opnd_Type
) then
13075 -- In an instance or an inlined body, there may be inconsistent views of
13076 -- the same type, or of types derived from a common root.
13078 elsif (In_Instance
or In_Inlined_Body
)
13080 Root_Type
(Underlying_Type
(Target_Type
)) =
13081 Root_Type
(Underlying_Type
(Opnd_Type
))
13085 -- Special check for common access type error case
13087 elsif Ekind
(Target_Type
) = E_Access_Type
13088 and then Is_Access_Type
(Opnd_Type
)
13090 Conversion_Error_N
("target type must be general access type!", N
);
13091 Conversion_Error_NE
-- CODEFIX
13092 ("add ALL to }!", N
, Target_Type
);
13095 -- Here we have a real conversion error
13098 Conversion_Error_NE
13099 ("invalid conversion, not compatible with }", N
, Opnd_Type
);
13102 end Valid_Conversion
;